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					                                                          APRIL 2010




                                                     Each
                                                 patient’s
                                                  corneal
                                                 thinning
                                               disorder is
                                                  unique,
                                                   so you
                                                     must
                                               select just
                                    the right lens design
                                       to accommodate
                                      every irregularity.




Supplement to
                                             ALSO INSIDE:
                               • Prescribe Beyond the Ordinary
                April 2010
                             • Biofilms: A Look Inside the Case
                                                       News Review
                                                             VOL. 147, NO. 3

                In the News

    Starting May 1st, British Columbia
                                                Ocular Allergies
    residents will be able to purchase
    contact lenses and ophthalmic
    glasses online without a prescrip-
    tion or eye exam from an eye care
                                                On the Rise
                                               A
    practitioner. The new legislation is                ccording to a recent survey     contact lenses prescribed for monthly
    intended to address complaints from                 conducted by the Asthma &       replacement said that they replaced
    patients who suggest that it’s difficult             Allergy Foundation of Amer-     their lenses as prescribed. Over half
    to obtain copies of their prescriptions    ica (AAFA), about 67% of allergy         (55%) replaced them within five
    from their eye care practitioners          sufferers say that spring is the time    weeks, 23% at eight weeks or more
    to legally purchase contact lenses
                                               of year when eye allergy symptoms        and 14% at ten weeks or more.1
    online. But, this legislation is meeting
                                               are worst. For respondents who              To help allergy sufferers better
    opposition from the British Columbia
    Association of Optometrists (BCAO).        wear contact lenses, spring is par-      understand and manage their condi-
    “The BCAO intends to mount a               ticularly frustrating; as nearly half    tion, the AAFA offers a free educa-
    campaign to oppose the regula-             (45%) say that their eye-related         tional brochure titled “Eye Health
    tory changes being imposed on our          allergy problems often prevent them      and Allergies.” The brochure, which
    profession,” says Antoinette Dumalo,       from wearing their contacts, and one     also includes smart allergy season
    O.D., BCAO president.                      in ten (12%) admits to having to         strategies for contact lens wearers,
                                               stop wearing their contacts because      can be viewed or downloaded at
    Menicon Co., Ltd. has acquired
    all shares of Tomey from Tomey             of allergies.                            www.aafa.org/eyeallergies. The bro-
    Shoji Inc. Tomey Co., Ltd. is a major         The majority of respondents report    chure, along with a certificate a free-
    Japan-based manufacturer of                that they wear their lenses two weeks,   trial pair of 1- Day Acuvue Moist
    contact lens care solutions, soft          one month or longer. In a recent study   contact lenses, is also available at
    contact lenses and RGP materi-             presented at the 87th annual meeting     www.acuvue.com/seasons.
    als. The company has been the              of the American Academy of Optom-        1. Hickson-Curran S, Chou P, Gardere J. Longer prescribed
    contracted supplier to Menicon of          etry, researchers reported that only     replacement intervals leads to more stretching of frequent replace-
    contact lens care solutions and ex-        about one-third (36%) of wearers of      ment contact lenses. Presented at American Academy of Optom-
    clusive supplier of Menicon monthly                                                 etry Meeting, November 2009.
    replacement soft contact lenses, and
    latheable RGP and soft lens materi-
    als, including Menicon Z, Menicon
    EX, Menisoft and Menicon Soft 72.
    This acquisition enables Menicon to          A Clear Idea
    control the manufacture of its lenses          Bausch + Lomb has replaced the traditional white high-density
    and lens care products. Tomey will           polyethylene package of Renu Fresh multipurpose contact lens solu-
    be renamed MeniconNect.                      tion with a transparent one, made of a healthcare-approved grade of
                                                 polyethylene terephthalate. The new clear container allows contact
    Art Optical has launched an addi-
    tional GP lens material in the Thinsite      lens wearers to see exactly how
    design. Thinsite2—offered exclu-             much solution is remaining; it is
    sively in BostonXO2 lens material—is         also easier to recycle. A special tex-
    now also available in Boston ES and          ture was also added to the bottle
    Boston EO material options. Thinsite2        design, which facilitates high-speed
    utilizes patented design technology          production and enhances user ergo-
    combined with advanced lathing tech-         nomics. The new bottle features a
    niques to generate a thinner overall
                                                 snap-on cap and is available in 2oz,
    lens profile that reduces lens mass
                                                 4oz, 8oz, 12oz and 16oz sizes.
    and increases oxygen transmissibility
    while maintaining lens stability, the          For more information, go to
    company says.                                www.renu.com.



2      REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
JOBSON MEDICAL INFORMATION LLC
11 Campus Blvd., Suite 100
Newtown Square, PA 19073
Telephone (610) 492-1000
Fax (610) 492-1049
Editorial inquiries (610) 492-1003
Advertising inquiries (610) 492-1011
E-mail rcl@jobson.com

EDITORIAL STAFF                                         Board Certification
EDITOR-IN-CHIEF                                            The American Board of Clinical Optometry (ABCO) is now
Amy Hellem ahellem@jobson.com
CLINICAL EDITOR
                                                        accepting applications for board certification in general opto-
Joseph P. Shovlin, O.D., F.A.A.O. jpshovlin@gmail.com   metric practice. Board certification by the ABCO is available
EXECUTIVE EDITOR                                        in the United States and Canada, and its requirements include
Arthur B. Epstein, O.D., F.A.A.O.
artepstein@artepstein.com                               completion of an accredited course of study resulting in an O.D.
ASSOCIATE CLINICAL EDITOR
Ernie Bowling, O.D., F.A.A.O. bowling@roman.net
                                                        degree, passing required NBEO examinations or their equiva-
ASSOCIATE CLINICAL EDITOR                               lent and licensure by at least one state, provincial or territorial
Alan G. Kabat, O.D., F.A.A.O. kabat@nova.edu            licensing body. These standards are identical to those required
ASSOCIATE CLINICAL EDITOR
Christine W. Sindt, O.D., F.A.A.O.                      by State licensing boards and are typical for board certification
christine-sindt@uiowa.edu
                                                        throughout the health care professions, says ABCO.
ASSOCIATE EDITOR
Izabella Alpert ialpert@jobson.com                         “Recent events have created a need for a credible board certi-
ASSOCIATE EDITOR                                        fication and maintenance of certification process in optometry.
Leah Addis laddis@jobson.com
                                                        No optometrist should be denied access to insurance panels or
CONSULTING EDITOR
Milton M. Hom, O.D., F.A.A.O. eyemage@mminternet.com    financially penalized due to a lack of board certification. The
CONSULTING EDITOR                                       ABCO’s process for obtaining board certification respects the
Stephen M. Cohen, O.D., F.A.A.O.
stephen.cohen@doctormyeyes.net                          authority of state licensing boards and at the same time recog-
ART/PRODUCTION DIRECTOR                                 nizes and celebrates optometric competence and ability,” says
Joe Morris jmorris@jobson.com
ART/PRODUCTION
                                                        ABCO President and Executive Director, Art Epstein, O.D.,
Alicia Cairns acairns@jobson.com                        F.A.A.O.
AD PRODUCTION MANAGER                                      The ABCO has adopted a maintenance of certification (MOC)
Pete McMenamin pmcmenamin@jobson.com
                                                        process based on the combined recommendations of the Ameri-
BUSINESS STAFF
PRESIDENT/PUBLISHER
                                                        can Board of Medical Specialties, and the Association of Regu-
Richard D. Bay rbay@jobson.com                          latory Boards of Optometry Council on Endorsed Licensure
SALES MANAGER, NORTHEAST,                               Mobility for Optometrists. The ABCO MOC consists of meeting
MID ATLANTIC, OHIO
James Henne jhenne@jobson.com                           specified continuing education standards combined with innova-
SALES MANAGER, SOUTHEAST, WEST
Michele Barrett mbarrett@jobson.com
                                                        tive online learning and self-assessment programs that run in
REGIONAL SALES MANAGER                                  five-year cycles.
Kimberly McCarthy kmccarthy@jobson.com                     For information, go to www.boardofclinicaloptometry.org.
EDITORIAL BOARD
Mark B. Abelson, M.D.
James V. Aquavella, M.D.
Edward S. Bennett, O.D.
Brian Chou, O.D.
S. Barry Eiden, O.D.
                                                        New Drug Delivery Contact Lenses
Gary Gerber, O.D.                                         University of Florida, Gainesville, researchers have developed
Susan Gromacki, O.D.
Brien Holden, Ph.D.
                                                        a contact lens that slowly releases vitamin E to the eye, which
Bruce Koffler, M.D.                                     aids in the delivery of IOP-lowering drops. The invisible mol-
Jeffrey Charles Krohn, O.D.
Kenneth A. Lebow, O.D.
                                                        ecules of vitamin E slow the delivery of the glaucoma medica-
Kelly Nichols, O.D.                                     tion from the lens into the eye. The drug released from the lens
Robert Ryan, O.D.
Jack Schaeffer, O.D.
                                                        into the eye stays in the tears longer than with eye drops alone.
Kirk Smick, O.D.                                        The lenses are due for human trial within the next two years
Barry Weissman, O.D.
                                                        and could also be loaded with drugs for cataracts and other
REVIEW BOARD                                            ocular conditions.
Kenneth Daniels, O.D.
Michael DePaolis, O.D.
Desmond Fonn, Dip. Optom. M. Optom.
Robert M. Grohe, O.D.
Patricia Keech, O.D.
Jerry Legerton, O.D.
Charles B. Slonim, M.D.                                 Advertiser Index
Mary Jo Stiegemeier, O.D.
Loretta B. Szczotka, O.D.
Michael A. Ward, F.C.L.S.A.                             Aton .................................................................................... Cover 3, 4
Barry M. Weiner, O.D.                                   CIBA Vision ..................................................................Cover 2, Page 1


                                                                                             REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010                    3
    contents             Review of Cornea & Contact Lenses | April 2010
                                                                                                 ON THE COVER

    14 Making Sense of the Irregular Cornea
              Each patient’s corneal thinning disorder is unique, so you must
              select just the right lens design to accomodate every irregularity.
              Brian Chou, O.D., and Barry A. Weissman, O.D., Ph.D.




23 Prescribe Beyond the                                                             Departments
   Ordinary                                                                         2    News Review
       Differentiate your practice by utilizing
       sophisticated contact lens designs and                                       5    Editorial
       enhancing patients’ quality of life.                                              Don’t Forget About the Lens Case
       Jerry Legerton, O.D., F.A.A.O.                                                    Joseph P. Shovlin, O.D., F.A.A.O.

                                                                                    6    Gas-Permeable Strategies
                                                                                         Seek Out Ideal Candidates
                                                                                         John M. Rinehart, O.D., F.A.A.O.
29 Biofilms: A Look Inside
   the Case
                                                                                    7    Out of the Box
                                                                                         Just Add an Expiration Date
       How clean are patients’ lens cases, and                                           Gary Gerber, O.D.
       how often must they be replaced in
       order to avoid biofilm buildup on lenses                                      8    Down on the Pharm
       and cases?                                                                        Another Shot at Ocular Allergies
       Michael Mayers, O.D., F.A.A.O.                                                    Ernie Bowling, O.D., M.S., F.A.A.O.,
                                                                                         Dipl., and Gregg Russell, O.D.,
                                                                                         F.A.A.O., Dipl.

                                                                                    10   Derail Dropouts
                                                                                         How Young Is Too Young for Contact
                                                                                         Lenses?
                                                                                         Mile Brujic, O.D., and Jason Miller,
                                                                                         O.D., M.B.A.

                                                                                    12   Naked Eye
                                                                                         Clinical Confounders
                                                                                         Mark B. Abelson, M.D., C.M.,
                                                                                         F.R.C.S.C., Richard Abelson, M.S.,
                                                                                         and Daniel Dewey-Mattia

                                                                                    13   Lens Care
                                                                                         Nip It in the Bud
                                                                                         Christine W. Sindt, O.D., F.A.A.O.




4   REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                                                               Editorial
                                                                                By Joseph P. Shovlin, O.D., F.A.A.O.


Don’t Forget About the Lens Case
With all the inconsistent recommendations on lens storage case hygiene, what do we
tell our patients?



R
        ecent publications have alerted practitio-       How to Keep Lens Cases Clean
        ners to the importance of discussing the           So, what are the appropriate patient recommen-
        proper care of contact lens storage cases        dations regarding lens storage case care? For now,
with every patient on a consistent basis. Unfor-         patients should be instructed to clean, rinse (with
tunately, there is considerable discrepancy in the       solution—not tap water) and dry cases after every
recommendations of various agencies, industry,           use, removing all previously used solution.2,4 The
experts and practitioners.1,2 These conflicting          FDA advises lens wearers to flip the lens case over
recommendations are found in reviews of practice         to remove excess solution from the case and to
patterns about caring for cases. The uncertainty         replace the case every three to six months. Some
is primarily about drying positions, rinsing and         practitioners and industry representatives advocate
rubbing of lens cases, and recommendations for           monthly replacement of lens cases, even though
lens storage case replacement.2-4 But, it’s critically   there are no published studies to show any major
important to come to a consensus regarding the           advantages over the initial FDA recommendation.4
best method of care for lens storage cases.                The bathroom environment may predispose stor-
                                                         age cases to air-borne sources of contamination, so
What Lurks in the Case                                   patients should store their lenses and cases away
   Lens cases are a potential milieu for biofilm         from toilet areas.4 Finally, never allow patients to re-
formation and microbial contamination, which en-         use solution. Every patient who re-uses solution is at
ables microbes to resist antimicrobial agents. Also,     significantly higher risk for case contamination.4
growth in these biofilms tend to make microbes
generally more virulent (see “Biofilms: A Look           Stay Tuned
Inside the Case” pg. 29).1 Over the years, various         Although many groups, organizations and indi-
strategies have been employed to minimize and at-        viduals have suggested guidelines of care for contact
tempt to eliminate biofilm formation. In designing       lenses and accoutrements, additional research is
cases to resist biofilm formation by using silver        needed in order to reach a consensus among practi-
or sodium salicylate, it is crucial to be certain        tioners as to the optimum recommendations for lens
that these agents do not further enhance micro-          storage case care. These recommendations would be
bial virulence.1,4 The antimicrobial cases may be        similar to the cleaning instructions for lenses that
overwhelmed with microorganisms and perform              are included in FDA labeling.2,4 In the meantime,
poorly when there is a heavy inoculum.                   educating patients on frequent lens case replacement
   Another reason that lens case hygiene is critical     along with standard hygiene procedures will likely
is because storage cases have the highest rates and      reduce the chance of contamination.                                     RCCL


levels of contamination of all lens care accessories
                                                         1. Fleiszig SMJ, Evans DJ. Pathogenesis of contact lens-associated microbial keratitis. Optom Vis
and accoutrement. In fact, over half of all cases        Sci. 2010 Feb;87(4):1-8.
are contaminated with an array of pathogens.2 The        2. Wu YT, Hua Z, Harmis NY,et al. Profile and frequency of microbial contamination of contact lens
                                                         cases. Optom Vis Sci. 2010 Jan;87(3): 152-8.
most frequently recovered organisms are coagulase        3. Wu YT, Carndt N, Wilcox M, Stapleton F. Contact lens and lens storage case cleaning instruc-
negative Staphylococci, Bacillus spp. and fungi.3        tions: whose advice should we follow? Eye Contact Lens. 2010 Mar;36(2):68-72.
                                                         4. Hall BJ, Jones L. Contact lens cases: the missing link in contact lens safety? Eye Contact Lens.
There are definite differences in the frequency and       2010 Mar;36(2):101-5.
type of organisms found depending on the case lo-
cation examined. Different bugs hang out in differ-
ent locations of the lens case.2 Manufacturers must
keep this in mind when designing next-generation
lens cases, and perhaps better lens case design and
promotion of more thorough hygiene will reduce
the potential for contamination in the future.2-4              Joseph P. Shovlin, O.D., F.A.A.O., Clinical Editor



                                                                        REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010                                   5
          Gas-Permeable Strategies
          By John M. Rinehart, O.D., F.A.A.O.


Seek Out Ideal Candidates
Who is best suited for translating multifocal or bifocal correction with contact lenses?




S
      uccessful contact lens wear              • Inspect lids and lashes.
      begins with a good evalua-               • Express meibomian glands.
      tion and presentation of the             • Measure tear break up time.
lens options. Case presentation is             • Evert the upper lids and record
particularly important for multifo-         any giant papillary conjunctivitis             2. In this ideal lid position, the lower lid is at
cal candidates, many of whom do             and injection. This way, you’ll                the lower limbus, and the upper lid is below
not even know contact lenses are            know whether future lid problems               the upper limbus. This allows the lower lid
an option for their vision correc-          were pre-existing or caused by the             to support the lens on downgaze to allow for
tion. Even though we’re focusing            current lenses or solutions.                   translation into the near segment, and the
on translating multifocals, the                Always evaluate any contact lens            upper lid will be over the superior edge of the
principles are the same for spheri-         wearer or candidate for the following:         lens for increased comfort.
cal and toric GP lenses.                       • Any infection problems (figure 1).
                                               • Allergies.                                The Power of Suggestion
Ideal Candidate Selection                      • Meibomian gland dysfunction.                With the lens materials and
   Moderate uncorrected hyperopes              • Ocular surface disease.                   designs currently available, the
(+1.50D or greater) who think they             Only after any lids and cor-                success with multifocal and bifo-
see well in the distance may be the         neal problems are under control                cal lenses should be similar to
ideal candidates. In reality, they          should you begin the contact                   the success of toric lens fits. To
don’t see nearly as well in the dis-        lens fitting process.                           achieve this level of success, both
tance as they think, so their vision           It is also important to evalu-              the contact lens fitter and patient
will improve at all distances.              ate the position of the lids. For a            must:
   The low hyperope and the low             translating multifocal or bifocal,               • Be committed to the process.
myope may not be great candi-               the lower lid should be tangent to               • Have realistic expectations.
dates—the former sees well unaided          the lower limbus, and the upper                  • Understand the limitations to
in the distance, and the latter sees        lid should be 1mm to 2mm below                 this means of vision correction.
well unaided at near. These patients        the superior limbus. The lower lid               Just because your patients do
may experience a slight degradation         will support the lens on downgaze              not bring up the topic of contact
of vision that they do not wish to          and allow for easy translation.                lenses does not mean they are
tolerate. Additionally, large pupils        The upper lid should be over the               not interested. So, make specific
may cause ghosting with translating         superior lens edge for maximal                 recommendations during case pre-
designs because the pupil may be            comfort (figure 2). When the                    sentation, including multifocal or
in both the distance and near zones         lower lid is excessively low, the              bifocal contact lenses when appro-
simultaneously.                             zone of near power is too low for              priate. Patients who don’t inquire
   Translating multifocals are best         easy translation and this will likely          about contact lens correction may
suited for those with the need for          result in poor near acuity.                    have been told that they could
very sharp near and distance vision,                                                       not wear lenses or think they are
while many simultaneous designs                                                            too old. Remember: If you don’t
are best for those with a high de-                                                         present patients with lens options,
mand for intermediate vision, such                                                         they may never know that they
as those who spend most of their                                                           can enjoy the many benefits of
day at the computer.                                                                       contact lens wear.
   Beyond corneal health, topogra-                                                           Next month, we will discuss
phy and refraction, special atten-                                                         case presentation and trouble-
tion should be given to the eyelids.        1. In this patient, we can clearly see mixed   shooting translating multifocals
You should:                                 blepharitis (Staphylococcus and Seborrhea).    and bifocals.        RCCL




6    REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                                  Out of the Box
                                                                                           By Gary Gerber, O.D.


Just Add an Expiration Date
How to encourage those glasses-wearing patients to make the switch to contact
lenses now.



Y
        ou’ve seen Mr. Spectacle        it. So, consider adding the follow-        promotion going on right now.
        for three examinations          ing possibilities to your market-          If you want to get lenses, now is
        over the last five years         ing message.                               certainly the time to do so. Let me
and, every time, you’ve brought            When broaching the topic with           email you the link to our website,
up the prospect of him wearing          such patients as the one mentioned         where you can find more informa-
contact lenses. Each time you do,       above, introduce some sort of time-        tion about this special program.”
he expresses a genuine interest         sensitive offer. Something along              • When patients are directed to
and he’s always impressed that          the lines of limited-time special          your website to learn more, they
at every visit you have some-           pricing on a yearly supply of lenses       will see the details of the promo-
thing new to discuss. Yet, after        could work. Or perhaps, offer a            tion, along with an expiration date.
all these discussions, he is still      limited promotion tied in with Rx             • Upon entering the office, vis-
wearing glasses. Certainly, in          eyeglasses. Time-sensitive offers for      ible yet tasteful signage should
recent times, patients do have          plano sunglasses can be effective, as      espouse the same message, with
economic considerations. But,           can offering a limited-time extended       the same expiration date. When
we know from experience that            trial period. You might even try           appropriate, a one-page document
satisfied wearers rarely drop out        a combination of the above and             outlining the promotion could be
for financial reasons.                   test which option works best for           handed to the patient too—again,
                                        your patient population. Make the          with the same dating.
From Maybe to Yes                       limited-time offer patient-specific,           • As a staffer escorts the patient
   So, why are patients so re-          so it could be worded like, “If you        to the exam room, he or she can
luctant to pull the contact lens        are fit with contact lenses within 30       mention the offer one more time:
trigger? Simply because we are          days of your examination, the price        “Did you see the offer we’re run-
handing them an unloaded gun            of an annual supply of lenses will be      ning on contacts? Do you think
and not giving them reasons for         X instead of Y.”                           that’s something you might try?”
making the switch from glasses
to contact lenses immediately.          Drive the Message Home                     Be Subtle but Consistent
With these patients, few of us             Just as is the case with most mar-        To ensure that this approach
ever assign any urgency to help         keting ideas, you should approach          doesn’t turn from promotion to
push the patient toward saying,         this from multiple fronts. Phone           harassment, role-play a typical
“Yes!” To the contrary, we often        scripts, in-office signs, informa-          patient encounter from the patient’s
tell them, “You don’t have to           tion on your website and real-time         perspective. Once your signage and
decide right now. Think it over         patient discussions need to all be         documentation is in place, walk
and let us know what you think.”        in synch regarding your message.           through the process as though
What they think is, “Well, I guess      Consistency adds credibility as pro-       you were a patient. The messag-
I’ll just wait till next year. What’s   spective patients start to internalize,    ing should be subtle, yet persistent
the rush?” While it’s clinically        “This is just how it is.”                  and consistent. Rely on common
true that there is rarely a rush or        How can you bring this plan to          sense; the first time the patient says,
urgency to start wearing contact        fruition?                                  “Thanks, but no thanks!” you have
lenses, we can certainly put a few         • At the close of a phone call, a       to stop. The in-office signs of course
bullets in our marketing gun to         staff member could say, “I notice          will still be there, but there shouldn’t
nudge the patient ever so gently.       the last time you were here that           be any further discussion. Each of
                                        you talked to Dr. Jones about              these occurrences, rehearsed and
Make it Time-Sensitive                  contact lenses, but you were never         properly presented, can move your
 The concept of urgency or im-          fit. Make sure to ask him about             patient from “I’ll think about it,” to
mediacy has a time component to         lenses again—we have a special             “I’ll do it, and I’ll do it now!”    RCCL




                                                                       REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010          7
                        Down on the Pharm
                        By Ernie Bowling, O.D., M.S., F.A.A.O., Dipl., and Gregg E. Russell, O.D., F.A.A.O., Dipl.


Another Shot at Ocular Allergies
Practitioners are able to take advantage of a new treatment option for allergic
conjunctivitis sufferers.



A
        n estimated 60 to 90 mil-            drug is one drop into the affected         soft contact lenses. Lenses may be
        lion individuals suffer from         eye(s) b.i.d.                              reinserted after waiting 10 minutes.
        allergic conjunctivitis in the          The FDA approval of Bepreve             Bepotastine plasma concentrations
United States, and the prevalence            was based on two conjunctival              peaked at approximately one to two
may be increasing.1 While there are          allergen challenge (CAC) studies           hours post-instillation. And, plasma
a number of topical and oral treat-          in 237 patients. Bepreve was more          concentration at 24 hours post-
ments available, 31% of patients             effective than placebo in relieving        instillation were below the quantifi-
taking an allergy medication are             ocular itching induced by an ocular        able limit (2ng/mL) in 11/12 sub-
not fully satisfied with their current        allergen challenge, both at 15 min-        jects evaluated. The main route of
medication.2 Reports have indi-              utes post-dosing and at eight hours        elimination of bepotastine besilate is
cated that nearly 73% of patients            post dosing. The drug was deter-           urinary excretion—approximately
on allergy medication still suffer           mined to be safe and well tolerated.3      75% to 90% is excreted unchanged
from itchy, red, watery eyes.1 This             Additional results from Phase 3         in urine. It is not known if bepotas-
is why the more choices of medica-           clinical studies demonstrated that         tine besilate is excreted in human
tions we have access to, the better.         Bepreve was as effective in suppress-      milk; therefore, caution should be
Medications that target multiple             ing ocular itching in patients with        exercised when Bepreve is used by
mechanisms of action against in-             more severe itching as in patients         nursing women.3 The medication
flammatory mediators may be more              with all grades of ocular itching.4        is Pregnancy Category C, which
efficacious than single-mechanism                Results of other studies demon-         means it should be used only if the
medications, and this may make the           strated that Bepreve was effective         benefit exceeds the risk.
difference for some of our patients.         at reducing ocular itching for at             Ocular allergy diagnosis and
   Bepotastine is a topically active         least eight hours after dosing and         management is a large part of a
histamine H1 blocker that also               noticeably improved ocular itch-           medical optometric practice. With
inhibits the release of histamine            ing vs. placebo for up to 16 hours         the addition of Bepreve, we have
from mast cells. It suppresses               after dosing.5 In addition, evidence       another weapon in our therapeutic
the migration of eosinophil into             showed that Bepreve substantially          arsenal.         RCCL


inflamed tissues. Bepotastine                 reduces tearing caused by a con-
                                                                                        1. Tang EA, Matsui E, Wiesch DG, Samet JM. Epidemiology of
has been approved in Japan for               junctival allergen challenge for           asthma and allergic diseases. In: Middleton’s Allergy Principles
systemic use in the treatment of             at least eight hours after dosing.6        and Practice, Vol. 2 (7th ed.). Adkinson et al, eds. St. Louis. CV
                                                                                        Mosby, 2009.
allergic rhinitis since 2000 and for         Bepreve, dosed twice daily for six         2. Marple MA, Fornadley JA, Patel AA. Keys to successful
cases of urticaria/pruritus since            weeks, was also found safe with            management of patients with allergic rhinitis: focus on patience
                                                                                        confidence, compliance, and satisfaction. Otolaryngol Head Neck
2002. Bepreve (bepotastine besilate          minimal adverse events in a healthy        Surg. 2007 Jun;136(6 Suppl):S107-24.
ophthalmic solution 1.5%, ISTA               pediatric population from 10 to 17         3. Bepreve. ISTA Pharmaceuticals. Package Insert.
                                                                                        4. Williams JI, Gow JA, Gomes PA, et al. Treatment of ocular itch-
Pharmaceuticals) was approved by             years of age.7 The most common             ing with bepotastine besilate ophthalmic solution 1.5% for sub-
the U.S. Food and Drug Adminis-              reported adverse reaction, occurring       jects with more severe itching response in a conjunctival allergen
                                                                                        hallenge (CAC) clinical model of allergic conjunctivitis. Ann Allergy
tration in September 2009 for the            in approximately 25% of subjects,          Asthma Immunol. 2009;103(5) Suppl 3.
treatment of ocular itching associ-          was a mild aftertaste following             5. Macejko TT, McLaurin EB, [third author please?], et al. Bepotas-
                                                                                        tine Besilate Ophthalmic Solution 1.5% Reduces Ocular Itching Fol-
ated with allergic conjunctivitis.           instillation. Other adverse reactions      lowing Dosing in the Conjunctival Allergen Challenge (CAC) Model of
Bepreve is specifically indicated for         occurring in 2% to 5% of subjects          Acute Allergic Conjunctivitis. ARVO Abstract D926; May 7,2009.
                                                                                        6. Kurata FK, Macejko TT, [third author please?], et al. Bepo-
the treatment of itching associ-             were ocular irritation, headache and       tastine Besilate Ophthalmic Solution 1.5% Reduces Tearing at
ated with signs and symptoms of              nasopharyngitis.3                          8 Hours Following Dosing in a Multi-Site Clinical Trial Using the
                                                                                        Conjunctival Allergen Challenge (CAC) Model of Acute Allergic
allergic conjunctivitis.3 It’s supplied         Advise patients to remove con-          Conjunctivitis. ARVO Abstract D922; May 7, 2009.
in a 10ml squeeze bottle and is              tact lenses prior to instillation of       7. Protzko EE, Williams JI, [ditto] et al. The Safety of the Anti-
                                                                                        Histamine Bepotastine Besilate Ophthalmic Solution in a Healthy
designed for topical administra-             Bepreve; the preservative benzalko-        Pediatric Population From Ten to Seventeen Years of Age. ARVO
tion. The recommended dose of the            nium chloride may be absorbed by           Abstract D923; May 7, 2009.




8     REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                           What’s the Solution
                                                                                      Michael Mayers, O.D., F.A.A.O.


Every Patient Counts


W
            hat is one contact             have to increase new patients                on different solution technologies
            lens patient worth to          by 30% to account for approxi-               that match these superb lens ad-
            your practice? If you          mately 20% of the contact lens               vancements. Studies have illustrated
answered, “A fitting fee and a             dropouts. 1 In our practices, we             enhanced comfort for symptomatic
year’s supply of lenses,” you’re           should always be focusing on                 patients who were upgraded to a
missing the point!                         how to decrease the number of                POLYQUAD®/ALDOX® solu-
   I hear it all the time. Patients        dropouts and increase our bot-               tion.3-6
tell me, “The last doctor said             tom line.                                       A recent study conducted by
he couldn’t fit me with contact               The number one reason for a               John Rumpakis, O.D., M.B.A.,
lenses because of my astigma-              patient to drop out of lens wear             examined the lost revenue from
tism.” Or, “The last doctor just           is poor comfort or fit.2 Some                 just one contact lens dropout
couldn’t find a comfortable                patients have reported as many               in a practice. He found that the
pair of contact lenses for me.”            as two hours of uncomfortable                cost of a dropout was around
Or, “I was told that monovi-               wearing time throughout their                $24,000 over the lifetime of a
sion or bifocal contacts are just          day.3 Currently, about 60% of                practice. For example, say you
not the best option, but a nice            new fits or refits in the U.S. are             have 1,000 contact lens wear-
pair of spectacles will get the            silicone hydrogel lenses.4                   ers in your practice. A dropout
job done.” I cringe when I hear               As eye care practitioners, we are do-     rate of 20% for those 1,000
these statements. Both estab-              ing a great job educating our patients       patients yields 200 patients lost
lished and new practitioners               about these newer, more breathable           per year. When you take 200
must realize that in order to              silicone hydrogel lenses, but we need        patients and multiply that num-
grow 10% net for the year, they            to go the extra step and educate them        ber by $24,000, that equates
                                                                                        to $4.8 million over the life of
                                                                                        your practice. In conclusion,
         Number One Reason for Patient Drop Out                                         recommending the correct solu-
                                                                                        tion to your patients will yield
                                                                                        many benefits over the course
                                                                                        of a practice lifetime, and your
                                                                                        patients will thank you for their
                                                                                        newfound comfort!
                                                                                        1. Rumpakis JMB. New data on contact lens drop-
                                                                                        outs: an international perspective. Rev Optom. 2010
                                                                                        Jan;147(1):37-42.
                                                                                        2. Zigler L, Cedrone R, Evans D, et al. Clinical evaluation
                                                                                        of silicone hydrogel lens wear with a new multipurpose
                                                                                        disinfection care product. Eye Contact Lens. 2007
                                                                                        Sep;33(5):236-43.
                                                                                        3. Nichols JJ. Annual report: contact lenses 2009. Contact
                                                                                        Lens Spectrum. 2010 Jan;25(1):20.
                                                                                        4. Lin MC, Tatyana TF. Differences in protein-removal
                                                                                        efficiency among multi-purpose solutions. Paper # 2020
                                                                                        presented at: Association for Research in Vision and
                                                                                        Ophthalmology; April 28, 2008; Ft. Lauderdale, FL.
                                                                                        5. Young G, Keir N, Jones S. Clinical evaluation of long-
                                                                                        term users of two different contact lens care preserva-
                                                                                         tive systems. Poster presented at: BCLA; May 2008;
                                                                                         Birmingham, UK.
                                                                                         6. Corbin GS, Bennett L, Espejo L, et. al. A multicenter
 Top eye care provider reasons for contact lens wear dropout were discomfort (50%),
                                                                                         investigation of OPTI-FREE® RepleniSH® multi-purpose
 poor vision (16%) and expense (12%). 1                                                  disinfecting solution impact on soft contact lens patient
                                                                                         comfort. Clin Ophthalmol. 2010 Feb 2;4:47-57.




Sponsoredb y                                                                          Sponsoredb y
                        Derail Dropouts
                        By Mile Brujic, O.D., and Jason Miller, O.D., M.B.A.


How Young Is Too Young for Contact Lenses?
Many variables factor into the decision regarding a child’s candidacy for contact
lenses.



C
         ontact lenses provide               patients are conducive to contact         to educate parents on the safety
         patients with peripheral            lens success, but patient responsibil-    of contact lenses and clear up
         vision that is unattainable         ity is just as—if not more—impor-         any misperceptions. As discussed
with spectacles. And, visual acuity          tant. This is true with patients of       earlier, offering information
in those with high prescriptions is          any age, but it becomes critically        based on your previous fitting
usually better with contact lenses           important in the pediatric popula-        experiences coupled with current
vs. spectacles.                              tion. Practitioners may try to judge      research on contact lens safety
   With contact lenses, wearers do           the level of the child’s responsibility   in pediatric patients will increase
not have to think twice about get-           during the exam, but it is also criti-    parents’ comfort level for con-
ting involved in physical activity;          cal to discuss the child’s habits with    tact lenses.
there’s no fear of damaging their            the parent to determine whether the
glasses—and for those who lead               child is responsible enough to care       When to Consider Contact
active lifestyles, this is a huge func-      for contact lenses.                       Lenses?
tional benefit. But, what does this              But, be sensitive to the fact            We should not lose sight of the
mean for our pediatric population?           that some parents may not think           fact that our pediatric population
                                             that their child is responsible           may benefit from contact lenses
Physical Characteristics of the              enough for contact lenses due             for many of the same reasons that
Eye                                          to preconceived notions about             adults do. Contact lens consider-
   The interpalpebral fissure is              their child being too young for           ations aren’t significantly differ-
significantly smaller in the pediat-          contact lenses. In these instanc-         ent for children than they are for
ric population, and it is a critical         es, it is important to reassure           teenagers and adults. We have
consideration when fitting children           the parent that contact lenses            a rich pipeline of materials and
with contact lenses. Teaching chil-          are safe in children by draw-             designs in both soft and RGP
dren proper insertion and removal            ing from anecdotal experience             modalities that are well suited
techniques can be particularly               and also from recent research.            for most patients.
challenging. At times, a 13.8mm              Understand that age, although               Contact lenses provide the
diameter lens (or smaller) may offer         important, should not be the              optics directly on the eye, and
pediatric patients an advantage.             only factor in our final decision.        thus, minimize much of the
   Issues that are caused by measur-         Research has shown that both              magnification and minification
able differences in tear film function        children (ages eight to 12) and           that spectacle lenses and high
are typically not of much concern            teenagers (ages 13 to 17) can             hyperopic and myopic correction
in our pediatric population. Most            safely wear contact lenses.1              may induce. In the same manner,
young patients have a robust tear               Parents may think that because         contact lenses minimize the ef-
film and high-quality meibomian               their children do not take good           fects of aniseikonia secondary to
gland secretions. Also, they are less        care of their glasses and are             significant anisometropia.
likely to be taking medications that         constantly needing them to be               They are also a good option for
may alter the quality of the tear            adjusted, they will not be able to        those who lead active lifestyles.
film. From an ocular surface health           care for their contact lenses. One        Additionally, many enjoy the
standpoint, this population may be           possible reason that children             option of contact lenses simply
best suited for contact lenses.              are more likely to damage their           because they like the way they
                                             glasses: Those who are active             look without glasses.
Determining Patient                          are the most likely to damage
Responsibility                               their glasses. These children may         Improve Self Perception
  We have established that the               actually reap the most benefit               When fitting children with
physical characteristics of pediatric        from contact lens wear. Be sure           contact lenses, consider the self-


10    REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                                       Derail Dropouts




esteem benefits that may result.        Another common condition            A Case in Point
Over a three-year period, evi-        that will undermine successful          “Megan,” a 6-year-old female,
dence has shown a statistically       contact lens wear in children: al-    has expressed interest in contact
significant improvement in self-       lergic eye disease. These children    lens wear to both her parents
perception regarding physical         should be treated accordingly,        and myself, and her parents
appearance, athletic competence       and depending on the resulting        would like to know if she’s a
and social acceptance in children     ocular signs and symptoms, clini-     good candidate for lens wear.
wearing contact lenses vs. those      cal judgment should be used to        She has worn glasses for the
wearing spectacles.2                  determine whether contact lenses      past two years.
   According to Mitchell J. Prin-     are in the child’s best interest.       Megan is relatively mature for
stein, Ph.D., a clinical psycholo-      Common prescription ocu-            her age and does extremely well
gist at the University of North       lar treatments for allergic eye       in school. She plays competitive
Carolina, “Such a difference by       disease include Bepreve (bepo-        chess and is now starting to play
simply being fit in contact lenses     tastine, ISTA Pharmaceuticals),       basketball. Her best-corrected
is significant.” Such changes in       Elestat (epinastine HCl, Aller-       visual acuities are 20/25- O.D.,
a child’s psychological develop-      gan), Optivar (azelastine, Muro       20/25- O.S., and 20/20-2 O.U.
ment “set a new trajectory for        Pharmaceutical) and Patanol           with the following prescription:
their future development,” he         (olopatadine 0.1%, Alcon).            +4.25 – 1.00 x 010 O.D., +6.50
says.3 Certainly, this should not     These agents are all approved         – 0.75 x 010 O.S. Anterior and
be the sole reason to fit children     for b.i.d. dosing. Pataday            posterior segment examination
in contact lenses, but it is incum-   (olopatadine 0.2%, Alcon) is          were healthy O.U.
bent upon the practitioner to         the only treatment approved for         Megan was initially fit with
consider quality-of-life benefits      q.d. dosing.                          a prism-ballasted hyperopic/as-
when discussing contact lenses                                              tigmatic toric contact lens. She
with patients and parents.            Weigh All the Factors                 learned insertion and removal
                                        When considering a child’s          relatively quickly. At her first
Address Underlying Ocular             candidacy for lens wear, first and     follow-up visit, she told me that
Issues                                foremost, make sure that patients     she was much more comfort-
   Just as underlying ocular dis-     have no underlying conditions. If     able playing basketball in her
ease can compromise successful        they do, make sure to treat those     lenses. At this point, she wears
contact lens wear in teenagers        conditions accordingly, and de-       a silicone hydrogel toric contact
and adults, it can also affect a      pending on the severity, you may      lens successfully.               RCCL


child’s ability to wear lenses. An    need to reconsider lens wear.
example of such a hindrance is          Most children will, in fact,          Next month we will ask the
blepharitis, which can undermine      have a healthy anterior segment       question, “How Old is Too Old
successful contact lens wear in       and be ideal for lens wear. Un-       for Contact Lenses?”
children. Blepharitis responds        derstand the child’s level of re-       The authors would like to
well to eyelid hygiene regimens,      sponsibility through discussions      thank Dr. Mitch Prinstein for
such as lid scrubs. For cases that    with the parent, and consider the     his insights.
do not completely resolve with        effects of contact lens wear on a     1. Walline JJ, Jones LA, Rah MJ, et al. Contact Lenses
lid hygiene alone, an antibiotic      child’s self-perception. When all     in Pediatrics (CLIP) Study: chair time and ocular health.
                                                                            Optom Vis Sci. 2007 Sep;84(9):896-902.
such as azithromycin 1% used          factors align, fitting this patient    2. Walline JJ, Jones LA, Sinnott L, et al. Randomized trial
topically for two to four weeks       population is one of the most         of the effect of contact lens wear on self-perception in
                                                                            children. Optom Vis Sci. 2009 Mar;86(3):222-32.
will likely lead to resolution of     rewarding experiences a practi-       3. Personal communication. Mitchell J Prinstein. (Novem-
signs and symptoms.                   tioner can have.                      ber, 2009).




                                                                REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010                   11
          Naked Eye
          By Mark B. Abelson, M.D., C.M., F.R.C.S.C., Richard Abelson, M.S., and Daniel Dewey-Mattia


Clinical Confounders
The reported efficacy of a drug, both in clinical trials and in medical practice, may be
skewed by several factors.



N
         umerous aspects unrelated          allergen washout. The patho-          This occurs most commonly in
         to the active agent, such          physiology of allergy requires        diseases with wide fluctuations in
         as patient care, formula-          contact time with the conjuncti-      severity (e.g., allergy).
tion and disease variability can            va, so an artificial tear (placebo)      When inclusion criteria for a
influence both objective and sub-            instilled in the eye can interrupt    study require a baseline value
jective measurements. The widely            this process by washing away          that is above an individual’s mean
recognized phenomena known as               the allergen, leading to positive     value for their condition as a
the “placebo effect,” “the Haw-             placebo response rates of as high     whole, they may still be included
thorne effect” and “regression              as 70%.2 Tear substitutes used        in the study either by a chance
toward the mean” are some of the            as a placebo in dry eye trials        high reading at a screening visit
confounders that can often lead to          have also shown statistically         or through multiple screening
misleading or unexpected results.           significant improvement in tear        attempts. As a result, the reading
                                            film stability as measured by the      for their condition could appear to
The Placebo Effect                          Ocular Protection Index (OPI)         have improved at subsequent visits
   In clinical studies, placebos are        when compared to baseline mea-        (when in reality, it’s just decreasing
used as the basis of comparison in          surements.                            toward their average value), inde-
determining the efficacy and safety                                                pendent of whether or not they are
of a pharmacological therapy. If a          The Hawthorne Effect                  receiving active treatment.
drug benefits the patient beyond a              Knowledge that one is being
pre-defined threshold vs. placebo,           observed or studied can lead to       Other Factors
it may be said to be efficacious.            changes in behavior due to what          Patient exuberance to participate
   Ideally, only the active drug in         is known as the Hawthorne effect.     in a clinical study and meet inclu-
a study will show any effect (be it         With regard to clinical studies,      sion criteria can also influence ef-
positive or negative) on a patient’s        the Hawthorne effect will usu-        ficacy results through the inflation
signs and symptoms. In many                 ally cause study participants to be   of self-reported outcomes during
studies, however, the placebo               more compliant to their treatment     screening and baseline evaluations.
effect can skew the results with            regimen or increase their moti-       Likewise, the desire of the inves-
a measurable, observable or felt            vation to carry out instructions      tigator to enroll higher numbers
improvement not attributable to             beyond the degree to which they       of patients could cause them to
an active treatment. For example,           would in normal circumstances.        stretch baseline scores, which may
in a study of oral antioxidant                 Additionally, patients who         then cause a patient’s condition to
therapy for dry eye, subjective             receive instructions from a health    appear to have improved as the
parameters evaluated with Mc-               care provider will often assume       study progresses.
Monnies’ dry eye questionnaire              the clinician is acting out of con-      Bottom line: Clinicians must
were significantly improved. But,            cern for their wellbeing, which in    be cognizant of these effects both
only antioxidant-treated patients           turn increases the likelihood of      when prescribing medications
showed significant improvement               positive subjectively determined      based on clinical data and when
in tear-thinning time, goblet cell          self-reported results.                assessing patient improvement
density and metaplasia.1                                                          on medication.                RCCL


   The placebo effect also mani-            Regression Toward the Mean
                                                                                  1. Blades KJ, Patel S, Aidoo KE. Oral antioxidant therapy for
fests in non-psychological pa-                 This concept is based on the       marginal dry eye. Eur J Clin Nutr. 2001 Jul;55(7):589-97.
rameters. For example, ophthal-             realization that patients are most    2. Leino M, Ennevaara K, Latvala AL, et al. Double-blind group
                                                                                  comparative study of 2% nedocromil sodium eye drops with 2%
mic solutions used as placebos              likely to seek treatment or enter a   sodium cromoglycate and placebo eye drops in the treatment
in allergic conjunctivitis trials           clinical study for a condition when   of seasonal allergic conjunctivitis. Clin Exp Allergy. 1992
                                                                                  Oct;22(10):929-32.
can alleviate symptoms through              their symptoms are at their worst.


12   REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                          Lens Care Update
                                                                          By Christine W. Sindt, O.D., F.A.A.O.


Nip It in the Bud
Treating pre-existing conditions and keeping lenses clean are both key factors in
contact lens comfort.



B
       lepharitis and meibomian          be easier for patients to use. They       (e.g., omega-3 fatty acids, oral flax
       gland disease are significant      aim not to cause drying or flaking         seed oil) to modify the lipid com-
       causes of contact lens discom-    of the periorbital area or burning        ponent of the tear film and increase
fort and inflammation, and as such,       upon application, which enhances          break-up time.3 Short bursts of topi-
these conditions must be identified       patient compliance.                       cal antibiotic-steroid ointment are
and addressed prior to contact lens         Hot compresses are useful, but         effective in ameliorating lid disease.
fitting. In ocular surface disease suf-   they are sometimes difficult for
ferers, specific lens cleaning regimens   patients to apply, which leads to         Effective Lens Cleaning
may help improve comfort and             eventual noncompliance. I recom-             Contact lens cleaning is another
enhance the lens wearing experience.     mend that the patient apply hot           issue that must be addressed in
                                         compresses for five minutes two or         patients with lid disease in order
Recognize the Signs                      three times a day, depending on the       to ensure contact lens wearing
   In lid margin disease, inspissat-     severity of the lid disease. A wet        success. Ideally, patients must re-
ed meibomian glands, lid margin          washcloth may be ineffective, be-         move debris, toxins and pathogens
telangiectasias, collarettes and         cause it does not hold heat for five       from their lenses nightly. This can
decreased tear break-up time are         minutes. Various techniques can be        be done either through the use of
typical findings. Ten percent of          used to apply hot compresses. One         daily disposable contact lenses or
the population may have rosacea,         clean, inexpensive, reusable and          with specific cleaning techniques.
and up to 50% of rosacea pa-             effective option is to put dry rice in    For our patients who cannot
tients will have concomitant ocu-        a small sock and heat the sock in         wear daily disposable lenses, we
lar findings. The ocular findings,         the microwave until it is warm; pa-       recommend a digital rub with a
however, may precede the gener-          tients should be cautioned to avoid       preservative-free alcohol-based
alized facial symptoms by many           overheating the compress, as this         cleaner—such as Sereine Extra
years.1 In contact lens wearers,         can cause skin burns. For patients        Strength Cleaner (Optikem Care
toxins produced by the lid margin        who prefer to avoid a homemade            System)—for superior pathogen
bacteria are adsorbed into the           technique, there are commercial           and deposit control before soaking
lens, likely causing increased           hot pack products, such as OCu-           in a multipurpose solution.4,5
symptoms and staphylococcal              SOFT Goggles with reusable heat-
marginal keratitis complaints.2          ing elements.                             First Things First
                                            Patients who do not respond to            Patients with lid and ocular
Lid Disease Treatment                    this line of therapy, particularly        surface disease can effectively wear
   For hygiene-based treatment of        those with ocular rosacea, may            contact lenses as long as their con-
lid margin disease, it is important      require such medications as doxy-         ditions are diagnosed in a timely
to recommend products that are           cycline (oral), azithromycin (topical     fashion and specific attention
compatible with the lid and ocular       or oral) or nutritional supplements       is paid to treatment and proper
surface. Baby shampoo is often                                                     cleaning routines.                  RCCL


recommended to cleanse the eyelid                                                  1. Scheinfeld N, Berk T. A review of the diagnosis and treatment of
margins, but it can be harsh if not                                                rosacea. Postgrad Med. 2010 Jan;122(1):139-43.
                                                                                   2. Knop E, Knop N. Meibomian glands: part IV. Functional interac-
diluted, which may cause exces-                                                    tions in the pathogenesis of meibomian gland dysfunction (MGD).
sive drying of the periorbital area.                                               Ophthalmologe. 2009 Nov;106(11):980-7.
                                                                                   3. Alikhan A, Kurek L, Feldman SR. The role of tetracyclines in
Products with a foam pump, such                                                    rosacea. Am J Clin Dermatol. 2010;11(2):79-87.
as OcuSoft foaming eyelid cleanser                                                 4. 510(k) Summary of Safety and Effectiveness. Available at: www.
                                                                                   accessdata.fda.gov/cdrh_docs/pdf7/K071203.pdf. (Accessed
(Cynacon/OcuSoft) and Thera-                                                       February 2010).
Tears SteriLid Eyelid Cleanser           Capped meibomian glands may lead to       5. Ghajar M, Houlsby RD, Chavez G. Microbiological evaluation of
                                                                                   MiraFlow. J Am Optom Assoc. 1989 Aug;60(8):592-5.
(Advanced Vision Research), may          dryness.



                                                                          REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010                          13
     Making Sense
                   of the Irregular
                       Cornea
           Each patient’s corneal thinning disorder is unique, so you must select just
           the right lens design to accommodate every irregularity.
           By Brian Chou, O.D., and Barry A. Weissman, O.D., Ph.D.




                                        K
              Dr. Chou is                        eratoconus affects approxi-      irregularity patients, such as post-
              an industry                        mately one in 1,800 indi-        corneal surgery (penetrating kera-
              consultant                         viduals, according to an         toplasty, failed refractive surgery,
              and private               epidemiological study published in        post-LASIK ectasia), scarring from
              practitioner              1986.1 That statistic suggests about      corneal ulcers or trauma, or thinning
 in San Diego with a                    150,000 keratoconic patients in the       disorders, such as pellucid marginal
 clinical emphasis on                   United States. From this estimate, we     degeneration (PMD). Secondly, the
 contact lens prescribing               can deduce that the average eye care      management of keratoconus is chal-
 for irregular corneas.                 practitioner should encounter just a      lenging for both patients and prac-
              Dr. Weiss-                few keratoconus patients each year.       titioners alike, which warrants the
              man is a                    Yet, keratoconus seems to gar-          additional clinical attention.
              professor of
                                        ner a disproportionately greater
              ophthal-
              mology at
                                        amount of coverage within continu-        Extreme Eye Care
 Jules Stein Eye Insti-
                                        ing education lectures and trade             Keratoconus is a condition of
 tute, David Geffen                     articles. Arguably, this is because the   extremes. It frequently pushes our
 School of Medicine at                  concepts behind contact lens treat-       common clinical measurements to
 UCLA.                                  ment for keratoconus are broader in       the limit, while challenging our man-
                                        reach. They apply to other corneal        agement plan in the same fashion.


14   REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
   When refracting keratoconus          corneas are thin and weak, and                decades. This is in part due to
patients, the multifocality of the      this throws off the assumed cor-              better diagnostic sensitivity,
cornea often causes a variable          neal rigidity used by the tonom-              especially with the increasing
endpoint. In normal patients,           eters in giving their measured                use of corneal topographers in
the typical just-noticeable differ-     IOP. In these cases, you should               routine clinical practice. It also
ence during refraction is plus or       be on the lookout for other tell-             reflects newly identified kerato-
minus 0.25D. But in keratoconus,        tale signs of glaucoma, especially            conus patients who receive their
especially in advanced cases, it        optic nerve changes.                          diagnoses during consultations
is sometimes necessary to refract                                                     for laser vision. Keratoconus is
with a spherical lens change of plus    Increasing Prevalence?                        a widely accepted contraindica-
or minus 1.00D to 3.00D to give           The past decade seems to have               tion for LASIK, due to the risk
a discernable difference. Further-      brought forth a much larger                   of worsening patients’ corneal
more, the Jackson cross cylinder        number of newly diagnosed kera-               distortion. Still, it’s not difficult
(JCC) in the phoropter is often not     toconus patients than previous                to imagine why keratoconus
adequate to provide a noticeable
difference during refraction. One
strategy is to pull out the handheld
JCC marked with +/- 1.00D and               Recognizing Mild Keratoconus
hold that over the phoropter aper-             ”Michael,” a 20-year-old male, presented for routine examination with no sub-
ture or trial frame.                        jective changes in vision. His manifest refraction was -2.00 -1.00 x 170 (20/15-)
   With manual keratometry, you’ll          O.D. and -3.00 -0.25 x 160 (20/15-) O.S. The patient’s ocular health was unre-
find some keratoconic corneas so            markable with no observable corneal abnormalities. Wavefront aberrometry (ZView,
steep that their readings are out           Ophthonix) showed a notable asymmetry in total higher-order aberrations—0.12D
of range with drum readings. In             O.D. and 0.61D O.S. In particular, the left eye showed an unusually high amount of
these cases, tape a +1.25D or even          coma (0.48D). Manual keratometry showed grade 1 mire distortion in the left eye.
a +2.25D trial lens to the objective        These results prompted us to order corneal topography, which confirmed central
face of the keratometer (the side           steepening in the left eye.
that points toward the patient).               New glasses were prescribed, and the patient was advised of the diagnosis of
Use cellophane tape, and make               mild keratoconus. Michael was cautioned against rubbing his eyes and asked to
sure that the trial lens handle does        have other family members undergo eye examinations to rule out keratoconus. We
not obscure your ability to read            scheduled a one-year follow-up to examine his eyes for further corneal changes.
the mires. To get a rough estimate
of the actual K readings, add
8.00D or 16.00D to your mea-
surements, depending on whether
you’ve used a +1.25D or +2.25D
trial lens, respectively.
   If you are using a millimeters-of-
                                          Wavefront aberrometry demonstrated unusually elevated total higher order aberra-
radius-to-diopter conversion slide        tions in the left eye.
rule, don’t be surprised if you slide
the card all the way to the end and
still can’t get the needed reading
because the corneas are too steep.
For these less common conver-
sions, various online keratometry
converters are available.
   Intraocular pressure read-
ings in keratoconus—whether
with applanation or non-contact
tonometry—are often artificially
low. No, these patients do not            Corneal topography confirmed central steepening in the left eye.
have hypotony. It’s just that their


                                                                         REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010          15
patients—frustrated with inad-                    downturn.2 Yet, a rebound in                       an increased rate of keratoconus
equate vision from glasses and                    consumer confidence will once                      diagnosis.
soft contact lenses—are attracted                 again drive new laser vision cor-
to the prospect of laser vision                   rection consultations, along with                  An Inflammatory Etiology?
correction.                                       the byproduct of new diagnoses                        For years, keratoconus has
   Growth of the laser correc-                    of keratoconus.                                    been accepted as a non-inflam-
tion industry indirectly benefits                    In a retrospective analysis                     matory corneal ectasia. But, new
the keratoconus community;                        published in 2003 that examined                    data suggest that there may be
increased screening for keratoco-                 1,392 laser vision correction can-                 a low-grade inflammatory com-
nus prompted by consultations                     didates, researchers identified 13                 ponent to keratoconus.4-6 This
for laser vision correction cre-                  (0.9%) as having keratoconus,                      research has found that the tears
ate a larger pool of identified                   suspected keratoconus or pellu-                    of keratoconus subjects and those
keratoconus patients. In turn,                    cid marginal degeneration.3 This                   with suspected keratoconus have
a growing identified number of                    is much greater than the afore-                    a higher expression of inflam-
keratoconus cases incentivizes                    mentioned prevalence within the                    matory molecules, including
development of alternative and                    general population. So, while the                  Interleukin-6, TNF-alpha and
improved treatment. The number                    actual number of keratoconus                       MMP-9. Many clinicians have
of laser vision correction proce-                 cases is probably not increasing,                  noted that keratoconus patients
dures has plummeted in recent                     improved detection and greater                     tend to have corneal vasculariza-
years, mirroring the economic                     screening volume are leading to                    tion with superficial pannus and



     A Diagnostic Challenge
        ”Florence,” a 78-year-old female, presented for routine examination with a complaint of poor vision in her left eye with existing
     glasses. Her presenting acuity was +3.50 -2.00 x 097 (20/20) O.D., and +3.50 -2.25 x 074 (20/40-) O.S. Her manifest refraction was
     +3.75 -2.25 x 098 (20/20+) O.D., and +5.25 -2.50 x 084 (20/20+) O.S. Florence’s ocular health findings were unremarkable, and her
     corneas showed no abnormalities. New glasses with the manifest refraction were prescribed.
        One week later, she returned still complaining of poor vision in the left eye with the new glasses. The prescription was verified, but
     visual acuity in the left eye was 20/30. Repeated refraction was +6.25 -2.50 x 084 O.S., yielding 20/20-visual acuity. The refraction
     endpoint was variable, with a just-noticeable difference of approximately +/- 0.75D. The variable refraction endpoint, reduced best-
     spectacle corrected visual acuity and against-the-rule astigmatism were collectively suspicious for forme fruste keratoconus. Corneal
     topography was ordered and confirmed the presence of irregular steepening in the left eye.
        The patient was advised of the diagnosis and presented with the contact lens option, but she elected to stay with spectacles.
        This case illustrates how the multifocal nature of the keratoconic cornea can cause variable vision and a multimodal refraction
     endpoint. Given this patient’s age, however, progression (especially to the point of requiring corneal surgery) is unlikely without other
     factors, such as refractive surgery.




     A variable refraction in the left eye prompted corneal topography, which confirmed asymmetric corneal steepening in that
     eye.




16     REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
also deep stromal vessels; perhaps     of the higher-order aberration          randomized, controlled clinical
this is another byproduct of low-      coma.8,9 For a patient with pure        trials to evaluate the safety and
grade corneal inflammation as          coma, a point source of light will      efficacy of CXL for progressive
well as contact lens overwear.7        look like a tailed comet rather         keratoconus and corneal ectasia.16
   If low-grade inflammation           than a compact point. Elevated          Interim data of the first trial, pre-
indeed exists with keratoconus, it     higher-order aberrations create         sented at the American Society of
begs the question whether there        greater response variability dur-       Cataract and Refractive Surgery
is a role for immunosuppressants,      ing manifest refraction and might       (ASCRS) Meeting in April 2009,
such as topical cyclosporine for       tip off a clinician to suspect kera-    showed impressive results. With
the off-label use in minimizing        toconus (see “A Diagnostic Chal-        457 eyes treated with CXL, the
advancing corneal distortion in        lenge,” pg. 16).                        procedure indeed appeared to
keratoconus, especially during            If wavefront aberrometers            decrease corneal curvature while
the adolescent years. But, its effi-   significantly replace the role of       increasing corneal rigidity.17 Com-
cacy in altering keratoconus pro-      autorefractors in the primary care      plications appeared to be few,
gression has not been definitively     setting, they will provide practi-      including four cases of infiltrates
established. Certainly, many           tioners with yet another tool for       (0.8%), four cases of delayed re-
clinicians treat the atopy that        detecting mild keratoconus. For         epithelialization and one case of
commonly accompanies kerato-           example, if a patient displays an       uveitis, which may not have been
conus with topical anti-allergy        elevated coma with aberrometry,         related to the treatment.17
drugs, such as Patanol (olopa-         it may prompt the clinician to
tadine 0.1%, Alcon) or Pataday         order a corneal topography and          Corneal Keratoplasty:
(olopatadine 0.2%, Alcon), Alrex       confirm the existence of mild           Lamellar and Full-Thickness
(loteprednol, Bausch + Lomb), or       keratoconus.                               Penetrating keratoplasty is
various over-the-counter ketoti-                                               regarded as the end-of-the-line
fen eye drops.                         Collagen Cross-Linking                  treatment for keratoconus. One
                                          Collagen cross-linking (CXL) is      study published in 1994 found
Diagnosing Mild                        an investigational procedure that       that 22% of keratoconic patients
Keratoconus                            is suggested to halt keratoconic        required a penetrating keratoplas-
   One of the classic manifesta-       progression.10,11 Riboflavin drops      ty to rehabilitate vision.18 With
tions of advanced keratoconus is       are applied to the surgically de-       improved contact lens treatment
Munson’s sign, where the lower         epithelialized cornea, which is         and surgical alternatives includ-
eyelid margin deflects over the        then exposed to ultraviolet A light     ing Intacs (Addition Technology)
cone apex. Yet, this is not use-       for 30 minutes. The result: an          and CXL, however, it is likely that
ful for diagnosing mild or forme       increased biomechanical stiffness       the actual number of keratoconus
fruste keratoconus. One of the         of the cornea and reduced cor-          patients undergoing penetrating
emerging diagnostic tools for          neal curvature, due to riboflavin/      keratoplasty is significantly lower
mild keratoconus is wavefront          UVA-induced cross-linking of the        today. Still, corneal transplanta-
aberrometry. While the older           corneal collagen. Biomechanical         tion is indicated when corneal
literature describes irregular         measurements have indicated that        distortion, tensile weakening and
astigmatism as a hallmark of           cross-linking can increase human        progressive thinning (leading to
keratoconus, a more up-to-date         corneal rigidity by over 300%.12        visual fluctuations) and scarring
description is that keratoconus           While the results to date are        in the visual axis are too severe
patients have an unusually ele-        encouraging, rare complications         for any other treatment to restore
vated amount of cornea-related         include corneal melt with per-          good vision. Overall, penetrating
higher-order aberrations or            foration and permanent corneal          keratoplasty is a highly successful
refractive error that is not cor-      haze.13,14 Another study reported       surgery; about 95% of patients
rectable using the lower-order         four cases of keratitis and corneal     achieve an optically clear donor
components of sphere, cylinder         scarring from a total of 117 kera-      cornea. Still, most will require
and axis (see “Recognizing Mild        toconic eyes treated with CXL.15        post-operative refractive correc-
Keratoconus,” pg. 15). In par-            In January 2008, it was              tion—up to 30% require spec-
ticular, keratoconus patients tend     announced that the U.S. Food and        tacles and 47% require contact
to have an elevated magnitude          Drug Administration permitted           lenses afterwards.19


                                                                   REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010   17
                                                               it’s currently dif-   New Contact Lens
                                                               ficult to foresee     Treatment
                                                               which of these           Rigid gas-permeable (RGP)
                                                               two procedures,       contact lenses are the primary
                                                               DALK or IEK,          therapy for restoring functional
 1. In Blanchard’s Asymmetric Corneal Technology (ACT), one    or yet another        vision in keratoconus. The rigid
 quadrant of the lens has a steeper peripheral curvature.      procedure under       lens surface creates a smooth,
                                                               development, will     artificial surface to mask the
    In recent years, some corneal            prove to be most efficacious for        underlying corneal irregularity,
surgeons prefer new lamellar                 treating keratoconus.                   so that light can properly focus
keratoplasty to traditional pen-                                                     into the eye. Despite their opti-
etrating keratoplasty (PK). Deep             Intacs for Keratoconus                  cal function, RGP lenses do not
anterior lamellar keratoplasty                  Intracorneal ring implanta-          retard the progression of kera-
(DALK) entails using filtered                tion (Intacs) for keratoconus           toconus. In fact, several studies
air to separate the underlying               was first performed in 1997             have implied that these lenses
Descemet’s membrane and endo-                in France. 24 Since then, Intacs        may even bring about keratoco-
thelium from the corneal stroma,             have become accepted as a               nus.30-32 Yet, because RGP lenses
called the Anwar “big bubble”                surgical alternative for cer-           are the treatment for keratoconus
technique. The advantages of                 tain keratoconus patients. The          and because early keratoconus
DALK include avoidance of intra- procedure can improve both                          can be subtle to detect, a caus-
ocular surgical risks, preserva-             uncorrected (UCVA) and best             ative relationship between RGP
tion of the host endothelium and             spectacle-corrected visual acu-         wear and keratoconus—if it even
the option of possible PK later if           ity (BSCVA), and it can reduce          exists—may be impossible to
needed.20 One retrospective cohort irregular astigmatism in corneas                  prove or disprove.33 Keratoco-
study compared outcomes of                   with and without scarring. 25 A         nus patients need not abandon
DALK and PK and found that the long-term study that followed                         RGP lens wear out of fear that it
DALK group had a significantly               the results of Intacs for kerato-       will exacerbate progression. The
lower incidence of post-operative            conus for five years found that         benefits from functional vision
complications compared with PK               the majority of patients experi-        greatly outweigh any unproven
cases, including allograft rejection enced improved UCVA, BSCVA                      concern about progression caused
and glaucoma.21 Another study,               and refraction without evidence         by lens wear.
however, found a similar rate of             of progressive sight-threatening           There are several excellent pro-
complications between DALK                   complications. 26 Although the          prietary RGP lens designs avail-
            22
and PK. (DALK is regarded as a               results are variable, some kera-        able for keratoconus, including
more technically difficult surgery           toconus patients after Intacs           Soper (David Thomas), McGuire
to perform.23)                               are able to avert corneal trans-        (David Thomas), Rose K and
    IntraLase-enabled keratoplasty           plantation and use glasses or           Rose K2 lenses (Blanchard),
(IEK) is another alternative to tra-         soft contact lenses to achieve          IKone (Medlens and Valley
ditional trefine penetrating kerato-         adequate vision. Keratoconus            Contax), NiCone (Lancaster),
plasty. The IntraLase femtosecond            patients who are undergoing             DynaZ+ nipple cone (Lens
laser (Abbott Medical Optics) is             Intacs should still expect to need      Dynamics), just to name a few.34
used instead of the trephine to              rigid lenses afterwards to obtain       Larger overall diameter versions
shape the edge of the corneal but-           the best vision.                        include Dyna Intra-Limbal (Lens
ton with complementary shapes                   More recently, some surgeons         Dynamics), GBL (ABB-Concise)
“sculpted” into both the host and            have used femtosecond lasers for        and Rose K2 IC (Blanchard).
donor edge. The broader wound                creating the lamellar channels for         Because asymmetric inferior
area leads to increased strength             inserting the Intacs segments, in       steepening of the cornea is com-
after healing, lessened astigmatism          lieu of using the mechanical spread-    monly observed with keratoco-
and perhaps even a faster recovery. ers.27-29 The femtosecond laser may              nus, inferior edge standoff can
    It is clear that traditional PK is       improve the safety of Intacs and        result in additional increased lens
under assault for the surgical treat-        increase the acceptance of Intacs as    awareness. It is possible to pre-
ment of choice in keratoconus. But, a treatment for keratoconus.                     scribe Rose K and Rose K2 lenses


18    REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
using Blanchard’s Asymmetric            those with decentered,
Corneal Technology (ACT),               oval and globus cones.
where one (usually the inferior)        ClearKone creates a
quadrant of the lens is made with       significant tear reser-
a steeper peripheral curvature to       voir to allow the rigid
decrease edge lift in a specific site   optics to vault over
(figure 1). There are other lens        the distorted cornea,       2. The Clearion Dual-Hinge concept allows practitioners
designs with similar technology         minimizing mechanical to independently adjust three lens zones. The ectasia
as well—e.g., Dyna Intra-Limbal         epithelial trauma dur- profile lens has a central zone that is significantly
Quadrant Specific Technology            ing lens wear (figures      steeper than the mid-peripheral and peripheral zones.
(Lens Dynamics).                        3 and 4).
   A relatively new fitting system         In situations where even the           scleral lens is to achieve complete
is represented in the Clearion          optimally prescribed hybrid lens          apical corneal vault and modest
dual-hinge lenses (Acuity One),         causes unavoidable epithelial             clearance over the limbal region
where there is an inner hinge point     touch with related discomfort,            of the eye. Most clinicians start
between the central base curve          one strategy is to piggyback the          with a contact lens back radius of
(BC1) and paracentral base curve        hybrid lens on a silicone hydrogel at least 1.00D steeper than cor-
(BC2) and an outer hinge point          lens.37 Dr. Chou has success-             neal steep K and refine as needed
between BC2 and the peripheral          fully piggybacked more than two           until the clinician can see limbus-
curve. One Clearion lens design is      dozen keratoconus patients wear- to-limbus clearance between the
the EP (ectasia profile), in which      ing the SynergEyes lenses with a          back of the lens and the anterior
BC1 is significantly steeper than       silicone hydrogel carrier in situ-        cornea in optic section with
BC2. BC1 and BC2 can be speci-          ations where the best hybrid lens         white light; fluorescein dye in
fied independently to minimize          alone caused epithelial microtrau- the entrapped tears will assist
apical bearing and achieve mid-         ma and related discomfort.                this observation. The second-
peripheral alignment (figure 2).           Scleral contact lenses are not         ary goal is to rest the lens on the
   A common clinical challenge          really new, nor are they novel in         conjunctiva several millimeters
in managing keratoconus arises          the management of keratoconus.            beyond the limbus, so that there
when the patient is unable to           In fact, one of the
comfortably wear optimally pre-         original uses of the
scribed RGP lenses. Piggybacking        early glass scleral lens-
the best mechanically fit RGP           es 100 years ago was
lenses over soft lenses—where the       in the optical treat-
posterior soft contact lens pro-        ment of keratoconus.
tects the underlying and sensitive      RGP scleral contact
corneal surface—has been one            lenses were developed
solution, especially in RGP lens-       by Don Ezikiel, O.D.,
intolerant keratoconus patients,        and Perry Rosen-
for 50 years.35 The recent avail-       thal, M.D., nearly a
ability of higher-Dk silicone           decade ago, and they
hydrogel lenses frees the clinician     have since become
from hypoxia concerns when              a viable—albeit
prescribing such lens systems and       often expensive and
allows for greater rates of clinical    technically challeng-
success.36                              ing—alternative to
   Another noteworthy new               piggyback and hybrid
lens design that may help such          lens designs.38,39 High-
patients is the SynergEyes Clear-       Dk RGP materials
Kone (SynergEyes). This hybrid          have allowed this
lens was introduced in 2009 to          advance.                   3. The SynergEyes ClearKone hybrid contact lens is
accommodate a larger number of             The clinical goal       designed to vault the cone apex with a surrounding tear
keratoconus patients, including         of fitting an RGP          reservoir.



                                                                       REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010   19
is neither too much physical pres-          irregularity. Post-LASIK ectasia,              who provide rehabilitative
sure (as defined by blanching of            while iatrogenic, is similarly                 contact lens treatment should
the conjunctival vasculature over           managed with RGP lens optics.                  take particular care in exam
much of the circumference of the            Certain patients with post-                    documentation. Unlike patients
lens) nor too little, which would           LASIK ectasia may benefit from                 with keratoconus who typically
allow the entry of bubbles into             Intacs surgery and/or CXL in the               accept their condition without
the optical zone. Large immobile            same way that certain kerato-                  blame, we have observed sev-
bubbles may lead to a decrease              conus patients do.41,42 Although               eral of our post-LASIK ectasia
in vision, corneal desiccation and          principles of contact lens and                 patients initiate litigation against
abrasion. Most of these lenses are          surgical management for kera-                  their refractive surgeon. In such
manufactured in overall diame-              toconus and post-LASIK ectasia                 instances, your exam records
ters of 15mm to 19mm, although              are similar, in our experience,                will be subpoenaed, and you will
some clinicians prefer even larger          there are more emotional issues                be called to testify.
lenses, up to 24mm or more;                 in post-LASIK ectasia patients,
lenses with overall diameters that          including anger, resentment and                The Antithesis of
are less than 15mm are usually              distrust. These patients may                   Commodity
avoided, as they tend to rest on            believe they have brought poor                    The pattern of corneal irregu-
the limbus.                                 vision upon themselves by choos-               larity—whether in keratoconus or
   Recent advances in instrument            ing elective surgery, or they                  other thinning disorders, corneal
technology, as exhibited by such            may think they were misled into                surgery, infection or trauma—is
diagnostic tools like the Visante           having unwise surgery. When                    unique to each eye. That is why
OCT (Carl Zeiss Meditec), pro-              managing patients complaining                  there can be no single lens design
vide a means of measuring corne-            of poor vision after refractive                that accommodates every irregu-
al and scleral contour beyond the           surgery, eye care practitioners                lar cornea.
range of placido-based corneal
topography. Bill Meyers, Ph.D.,
and Jerry Legerton, O.D., M.S.,                 Quick Clinical Tips
M.B.A., used the distribution of
scleral contour data to design a                   • Aggressively prescribe topical combination antihistamine/mast-cell stabiliz-
novel mini-scleral lens (15.5mm),               ers. Eye rubbing is common among keratoconus patients and is implicated in its
which holds promise of an                       genesis. The safest option is for keratoconus patients to refrain from rubbing their
improved scleral contact relation-              eyes. Sometimes it is easier said than done, which is why allergy eye drops for
ship along with reduced practitio-              keratoconus patients are appropriate.
ner chair time and reordering.40                   • Glasses are not contraindicated. A surprising number of keratoconus patients
(See “It’s Time to Rethink Mini-                benefit from glasses. Even if the vision with glasses is poor vs. that with RGP
Scleral Lenses” in this month’s                 lenses, spectacles can help them function around the house if their eyes are
Review of Optometry for more                    too irritated to wear lenses. Additionally, keratoconic patients who already wear
on this new lens design.)                       lenses may benefit from wearing glasses over their lenses to compensate for
   Once a “reasonable” mechani-                 residual astigmatism.
cal fit is achieved, over-refrac-                  • Assume that keratoconus is bilateral, especially because some of these
tion defines the optics for                     patients inquire about having LASIK in their “good” eye. Even if the disease
optimal vision just as in other                 appears to be unilateral, the likelihood is that the asymmetry is so great that your
paradigms of RGP lens prac-                     clinical measurements don’t have the sensitivity to detect its existence in the
tice, and evaluation during the                 “good” eye.
adaptation phase will detect any                   • Advise patients to let their relatives know that if they undergo a LASIK evalu-
needed alterations in optics or fit             ation, they should mention that keratoconus exists in the family.
to achieve best results.                           • Direct keratoconus patients to the National Keratoconus Foundation website
                                                (www.nkcf.org), which provides patients with information and support.
Keratoconus, Unnaturally                           • Edge design is critical for comfort and avoiding unwanted giant papillary
  Keratoconus is the prototypi-                 conjunctivitis (GPC), which will minimize wearing time. Use special cleaners and
cal, naturally occurring eye con-               avoid using steep, abrupt lenticulars with high-minus prescriptions.
dition characterized by corneal


20   REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
   By comparison, disposable
hydrogel and silicone hydrogel
contact lenses follow a one-size-
fits-all model, and the value of a
practitioner’s clinical expertise
is minimized by direct-to-con-
sumer advertising in such cases.
Coupons for free trial lenses
strengthen the patient/product
relationship and the do-it-your-
self mentality among patients—
while disrupting the relationship
between patient and practitioner.
   The beauty of prescribing
contact lenses for irregular
corneas is that clinical success
stems from the practitioner’s                                   4. The ideal SynergEyes ClearKone fit lands on both the soft outer landing zone and
knowledge and skill, rather than                                rigid inner landing zone, with central apical clearance.
a result of a specific lens brand
marketing campaign. While                                       12. Wollensak G. Crosslinking treatment of progressive          thalmol. 2007 Jul;18(4):279-83.
“specialty” contact lenses once                                 keratoconus: new hope. Curr Opin Ophthalmol. 2006               28. Rabinowitz YS, Li X, Ignacio TS, et al. Intacs inserts
included toric and multifocal                                   Aug:17(4):356-360.                                              using the femtosecond laser compared to the mechanical
                                                                13. Gokhale NS, Vemuganti GK. Diclofenac-induced acute          spreader in the treatment of keratoconus. J Refract Surg.
contact lenses, this distinction                                corneal melt after collagen crosslinking for keratoconus.       2006 Oct:22(8):764-71.
is eroding. Fortunately, contact                                Cornea. 2010 Jan 29(1):117-9.                                   29. Ertan A, Kamburoglu G, Bahadir M. Intacs insertion
                                                                14. Raiskup F, Hoyer A, Spoerl E. Permanent corneal haze        with the femtosecond laser for the Management of kera-
lens prescribing for irregular                                  after riboflavin-UVA-induced cross-linking in keratoconus.      toconus: one-year results. J Cataract Refract Surg. 2006
corneas is a bastion in our pro-                                J Refract Surg. 2009 Sep:25(9):S824-8.                          Dec:32(12):2039-42.
                                                                15. Koppen C, Vryghem JC, Gobin L, et al. Keratitis and         30. Hartstein J. Keratoconus that developed in patients
fession, where our services unde-                               corneal scarring after UVA/riboflavin cross-linking for kera-   wearing corneal contact lenses: report of four cases. Arch
niably hold intrinsic value.                        RCCL        toconus. J Refract Surg. 2009 Sep;25(9):S819-23.                Ophthalmol. 1968 Sep;80(3):345-6.
                                                                16. Boyle E. FDA backs launch of collagen cross-linking         31. Brady HR. Keratoconus development in a contact lens
                                                                clinical trials. Available at: www.osnsupersite.com/view.       wearer. Cont Lens Med Bull 1972;5:23.
1. Kennedy RH, Bourne WM, Dyer JA. A 48-year clinical           aspx?rid=25785. (Accessed January 2010).                        32. Brightbill FS, Stainer GA. Previous hard con-
and epidemiologic study of keratoconus. Am J Ophthal.           17. FDA trial data positive for corneal collagen cross-         tact lens wear in keratoconus. Cont Int Lens Med J.
1986 Mar 15;101(3):267-73.                                      linking. Available at: www.modernmedicine.com/                  1979;5(3):4347.
a barometer for recession. Available at: www.nytimes.           modernmedicine/Clinical+News/ASCRS-FDA-trial-data-              33. Zadnik K, Barr JT. Diagnosis, contact lens prescribing,
com/2008/04/24/business/worldbusiness/                          positive-for-corneal-collagen/ArticleStandard/Article/deta      and care of the keratoconus patient. Boston. Butterworth-
24ihtlasik.1.12301419.html. (Accessed January 2010).            il/591528?contextCategoryId=46496&ref=25. (Accessed             Heineman; 1999:30.
3. Ambrósio R, Klyce S, Wilson S. Corneal topographic           January 2010).                                                  34. Caroline PG, McGuire JR, Doughman DJ. Preliminary
and pachymetric screening of keratorefractive patients. J       18. Tuft SJ, Moodaley LC, Gregory WM. Prognostic factors        report on a new contact lens design for keratoocnus. Con-
Refract Surg. 2003 Jan-Feb;19(1):24-9.                          for the progression of keratoconus. Ophthalmology. 1994         tact Intraoc Lens Med J 1978;4:69-73.
2. Barmaby FJ. Drop in Lasik eye surgery appears to be 4.       Mar;101(3):439-47.                                              35. Westerhout D. The combination lens and therapeutic
Lema I, Durán JA, Ruiz C, et al. Inflammatory response to       19. Brierly SC, Izquierdo L, Mannis MJ. Penetrating kerato-     uses of soft lenses. Contact Lens J. 1973;4:3-10.
contact lenses in patients with keratoconus compared with       plasty for keratoconus. Cornea. May 2000:19(3):329-332.         36. Weissman BA, Ye P. Calculated tear oxygen tension
myopic subjects. Cornea. 2008 Aug; 27(7):758-63.                20. Anwar M, Teichmann KD. Big-bubble technique to bare         under contact lenses offering resistance in series: pig-
5. Lema I, Durán JA. Inflammatory molecules in the              Descemet’s membrane in anterior lamellar keratoplasty. J        gyback and scleral lenses. Cont Lens Anterior Eye. 2006
tears of patients with keratoconus. Ophthalmology. 2005         Cataract Refract Surg. 2002 Mar;28(3):398-403.                  Dec;29(5):231-7
Apr:112(4):654-9.                                               21. Han DC, Mehta JS, Por YM, et al. Comparison of              37. Scheid T, Kaplan E. A novel keratoconic piggyback
6. Lema I, Sobrino T, Durán JA, et al. Subclinical keratoco-    outcomes of lamellar keratoplasty and penetrating               fitting utilizing a SiH lens and a Synergeyes KC Hybrid.
nus and inflammatory molecules from tears. Br J Ophthal-        keratoplasty in keratoconus. Am J Ophthalmol. 2009              Available at: www.siliconehydrogels.org/in_the_practice/
mol. 2009 Jun:93(6):820-4.                                      Nov;148(5):744-751.                                             mar_08.asp. (Accessed January 2010).
7. Shah SS, Yeung KK, Weissman BA. Contact lens related         22. Bahar I, Kaiserman I, Srinivasan S, et al. Comparison       38. Schein OD, Rosenthal P, Ducharme C. A gas perme-
deep stromal vascularization. Int Cont Lens Clin 1998           of three different techniques of corneal transplantation for    able scleral contact lens for visual rehabilitation. Am J
Sept;25(5):128-36.                                              keratoconus. Am J Ophthalmol. 2008 Dec;146(6):905-12.           Ophthalmol. 1990 Mar 15;109(3):318-22.
8. Jafri B, Li X, Yang H, et al. Higher order wavefront aber-   23. Watson SL, Ramsay A, Dart JK, et al. Comparison of          39. Schornack MM, Patel SV. Scleral lenses in the
rations and topography in early and suspected keratoco-         deep lamellar keratoplasty and penetrating keratoplasty         management of keratoconus. Eye Contact Lens. 2010
nus. J Refract Surg. 2007 Oct:23(8):774-81.                     in patients with keratoconus. Ophthalmology. 2004               Jan;36(1):39-44.
9. Alió JL, Shabayek MH. Corneal higher order aberrations:      Sep:111(9):1676-82.                                             40. Personal communication with William E. Meyers,
a method to grade keratoconus. J Refract Surg. 2006             24. Colin J. Intacs may be useful for select keratoconus        Ph.D., on March 12, 2010
Jun:22(6):539-45.                                               correction. Ocular Surgery News April 15, 1999.                 41. Pinero DP, Alio JL, Eceda-Montanes A, et al. Intracor-
10. Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-    25. Boxer Wachler BS, Christie JP, Chandra NS, et               neal ring segment implantation in corneas with post-laser
a-induced collagen crosslinking for the treatment of kera-      al. Intacs for keratoconus. Ophthalmology. 2003                 in situ keratomileusis keratectasia. Ophthalmology. 2009
toconus. Am J Ophthalmol. 2003 May;135(5):620-7.                May;110(5):1031-40.                                             Sep;116(9):1665-74.
11. Coskunseven E, Jankov MR, Hafezi F. Contralateral           26. Zkymionis GD, Siganos CS, Tsiklis NS, et al. Long-term      42. Winciquerra P, Camesasca F, Albé E, et al. Corneal
eye study of corneal collagen cross-linking with riboflavin     follow-up of Intacs in keratoconus. Am J Ophthalmol. 2007       collagen cross-linking for ectasia alter excimer laser
and UVA irradiation in patients with keratoconus. J Refract     Feb:143(2):236-244.                                             refractive surgery: 1-year results. J Refract Surg. 2009.
Surg. 2009 Apr:25(4):371-6.                                     27. Rabinowitz YS. Intacs for keratoconus. Curr Opin Oph-       Sep 22:1-12.



                                                                                                               REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010                        21
                 Prescribe
                                 Beyond
                                   the
                               Ordinary
                   Differentiate your practice by utilizing sophisticated contact
                   lens designs and enhancing patients’ quality of life.
                   By Jerry Legerton, O.D., F.A.A.O.



C
        ontact lens manufacturers        One possible answer is dissatisfac-                            Dr.
        have made low-cost molded        tion with their current lenses. When                           Legerton is
        lenses widely available to       the needs and preferences of the                               an author,
consumers. As a result, contact lens     patients are not satisfied with the                            lecturer,
fees and annual lens costs are a frac-   market-leading commodity offerings,                            inventor
tion of what they were two decades       the practitioner has an opportunity               and consultant to the
ago (in inflation-adjusted dollars).     to educate and guide them toward                  ophthalmic industry.
At the same time, the average con-       more suitable lens wear while under-              He was the managing
sumer may view contact lenses as a       scoring his or her own expertise.                 partner of a seven-
commodity, seeing no appreciable                                                           doctor practice in San
difference between market-leading        The Satisfaction Gap                              Diego for 26 years. He
lenses and lacking awareness of             Years ago, I wrote an article                  was the co-founder of
lenses that solve problems when          titled, “Our Two Most Powerful                    SynergEyes, and his 22
                                                                                           issued U.S. patents and
other lenses fall short. What’s worse    Tools,” referring to case history
                                                                                           more than 30 pending
is that patients may not care where      and consultation.1 As a result of
                                                                                           applications include
their lenses come from and have no       crunched scheduling, higher daily
                                                                                           inventions for corneal
appreciation for the distinct care       patient volumes and the shift of                  refractive surgery for
received from one eye care practitio-    primary care to a medical model,                  presbyopia, Paragon
ner vs. another.                         most practitioners likely spend less              CRT, hybrid contact
   Does this reality result in opti-     time on case history than in the                  lenses, regulation of
mized patient satisfaction with          past, which often leads to a reduced              myopia progression,
contact lenses? If it does, then why     opportunity for discovering unmet                 scleral contact lenses
do more than three million patients      patient needs and wants with regard               and contact lenses for
stop wearing lenses every year?          to their contact lens experiences.                wearable displays.


                                                                  REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010      23
     Walter Choate, O.D., F.A.A.O., Nashville, Tenn.
        “Daniel,” a 56-year-old male, is an avid reader and a competitive sharpshooter who wears PureVision (Bausch + Lomb) multifocal lenses. His
     case history elicited decreased near vision and adequate but not optimal distance vision. Manifest refraction and add requirement were -2.75
     -0.75 x170 O.D. and -2.50-0.75x170 O.S. with a +2.50D add O.U. Keratometry readings were 41.25 / 42.50 O.D. and 41.25 / 42.25 O.S.
        Daniel was prescribed and followed with SynergEyes Multifocal lenses. His manifest refraction was now -4.00 7.8/8.8 /1.9 +1.75 O.D.,
     and -3.25 7.9/8.9 / 1.9 + 1.75 O.S. The patient returned and reported, “I love my vision with these lenses! It’s great at distance and near
     with both lenses; I can never feel them, even after 14 hours of wear.” His best-corrected visual acuity measurements were 20/20-1, J-1
     O.D. and 20/20, J-1 O.S.

   So how do you measure up?             also lose by failing to stimulate the vision correction (contact lenses or
Consider taking a personal survey enthusiasm that comes with higher spectacle eyewear).
of your case history methods and         satisfaction, which is more likely to         • How many hours per day do
practices. Do your inquiries suc-        result in increased patient retention you wear your lenses? How many
cessfully uncover patients’ reduced and referrals.                                  of those hours are comfortable?
comfortable wearing times? Are                                                         • During which tasks do your
you able to identify a successful        Improving Case History: Two lenses most let you down? Where
wearer who is near to dropping           Minutes to Discovery                       do you struggle the most with your
out because of shortcomings in              Consider adding two minutes             vision?
the lenses’ visual performance           to your case history portion of the           • If you could “wiggle your nose”
for certain tasks? Case history,         exam, and incorporate some of the and change anything about your
more than any clinical measure,          following questions:                       contact lenses, what would it be?
is an indicator for considering             • Tell me the three things you             All of these questions are
the armament of lenses outside           most dislike about your current            designed to discover shortcomings
the high market share of                                                                        that you won’t discover
disposable spherical, toric                                                                     by asking the typical
and multifocal lenses.                                                                          questions: “How are you
   Each time a patient                                                                          doing with your eyes and
enters your office with an                                                                      vision? Are you having
implicit need left unex-                                                                        any problems with your
plored during the case                                                                          lenses? What brings you
history, and for which                                                                          in today?” Culturally,
treatment alternatives                                                                          Americans are simply
are not offered during                                                                          too accustomed to saying
consultation, this patient                                                                      “Fine,” or “Good.” when
walks out with a need left                                                                      someone asks, “How
unmet, and you lose an                                                                          are you?” Problems are
opportunity to be com-                                                                          bottled up and forgotten,
pensated for higher-value                                                                       and patients only realize
services and materials. I                                                                       that they should have
refer to this as ophthalmic                                                                     reported a nuisance when
entropy—the conversion                                                                          they get home.
of potential ophthalmic
care and economic return                                                                        Clinical
into a non-usable form.                                                                         Considerations
Such a conversion is a                                                                          for Extraordinary
clear lose-lose situation;                                                                      Prescribing
the patients lose because                                                                          Today’s toric lenses
their needs was not found                                                                       are quite advanced—even
or treated, and you lose     Topography over SynergEyes Multifocals demonstrates position       though they fall short
by prescribing lower-        of near segment within the pupil and simulated defocus of 20/20    of the power and axis
margin products. You         letter from simultaneous vision optics.                            offerings of spectacle


24       REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                                                   Robert Gordon, O.D., F.A.A.O.,
                                                                                                   Encino, Calif.
                                                                                                       “Mitch,” a 52-year-old male attor-
                                                                                                   ney with moderately advanced pellu-
                                                                                                   cid marginal degeneration, presented
                                                                                                   wearing custom toric soft contact
                                                                                                   lenses that provided excellent comfort
Proclear Mutifocal Toric provides a distance-center and near-center design, which                  but poor vision due to monocular dip-
may be prescribed for contralateral eyes.                                                          lopia. He had tried several RGP corneal
                                                                                                   lenses in the past, yet he was never
lenses and lens orientation, and even           and, “How many of those hours                      able to obtain adequate comfort or
though their rotational stability               are comfortable?” It is common                     prevent the lenses from dislodging on
compromises acuity. In a random-                for a patient to report 16 hours of                lateral eye movement. Clinical findings
ized crossover study at the Univer-             wearing time and 12 or 13 hours                    included inferior ectasia in both eyes
sity of Michigan, subjects wore a               of comfort. This is your opportu-                  with 5.00D of astigmatism in the right
pair of market-leading toric lenses             nity to offer a treatment plan that                eye, and 6.50D in the left eye—both
and then a pair of SynergEyes hybrid            includes testing a series of lenses                at oblique axes.
lenses. At the end of the study,                over a 90-day period. You can                          Mitch was reluctant to try RGP cor-
patients were asked which modality              include conventional and silicone                  neal lenses again due to his history. He
they preferred. Forty-four percent              hydrogel materials to challenge                    was presented with the options of being
preferred the hybrid lenses.2 Those             the current lens modality in an                    fit with SynergEyes Clear Kone lenses
who preferred the hybrid lenses                 effort to increase comfortable                     or RGP scleral contact lenses. Due to
enjoyed the improved visual acuity,             wearing time. Keep in mind that                    fitting issues, he was ultimately fit with
while those who selected the soft               oxygen delivery only addresses                     RGP scleral lenses, which eliminated his
toric lenses cited improved comfort             one health maintenance objec-                      monocular diplopia and provided excel-
as the reason. This is why your                 tive. Some patients will experience                lent visual acuity and comfort for up to
armamentarium should include both               increased comfortable wearing                      15 hours per day.
soft toric lenses and hybrid lenses to          time with conventional materials.
satisfy all patients. In my experience,         The range of material proper-                   and direction of air conditioners
hybrid lenses provide better acuity             ties and surface characteristics of             and changing of HVAC filters).
on average and should be considered             lenses provide different benefits to
for patients who complain of com-               the continuum of patients.                      Multifocal or Monovision: The
promised vision with soft lenses or                Additional strategies to consider            Power is in the Question
for those who report that visual acu-           include modulating care products,                  Most practitioners today adhere
ity is very important to them.                  training blink quality and quantity,            to the maxim, “If it ain’t broke,
   Refer back to the case history               recommending nutraceuticals and                 don’t fix it.” While this makes
questions, “How many hours a                    suggesting environmental engineer-              good sense and is particularly wise
day do you wear your lenses?”                   ing (e.g., with regard to proximity             in the face of full schedules, the
                                                                                                operative word is “broke.” How
                                                                                                do we, as eye care practitioners,
  Lee Rigel, O.D., F.A.A.O., East Lansing, Mich.                                                know if it’s broke or not when it
     “Nicholas,” a 14-year-old male with spherical myopia, had been wearing silicone            comes to the contact lens dropout
  hydrogel disposable lenses for approximately two years. Since the time of his initial         rate, if we don’t ask our patients?
  contact lens fitting, his myopic correction more than doubled to -3.50D, and both he and      If we don’t know it’s broke, we
  his parents were interested in a contact lens-based corneal reshaping approach in an          can’t fix it, and patients will wane
  attempt to reduce the rate of his myopic progression.                                         in their enjoyment of contact lenses
     CRT lenses (Paragon Vision Sciences) were prescribed, and Nicholas was able to             until they finally drop out. Ask the
  achieve 20/20- uncorrected vision in both eyes with no residual refractive error. He has      suggested case history questions,
  manifested no increase in his myopia during the 2.5 years of wearing this modality. He is     and you may find that the patient
  able to wear his CRT lenses every other night and still maintain his emmetropic status.       is dissatisfied with monovision.
                                                                                                You can recommend a presbyopic


                                                                                    REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010        25
     Dianne Anderson, O.D., F.A.A.O., Chicago, Ill.
        “Claire,” a 48-year-old female, had successfully worn a spherical RGP for distance O.D. and a bitoric RGP lens O.S. for near for four
     years. After discontinuing lens wear for eight months during chemotherapy treatment for breast cancer, she reported discomfort and
     decreased wearing time with her RGP lenses. Claire’s spectacle Rx: -3.50 -1.50 x 180 20/20 O.D. and -2.50 -2.50 x 010 20/20 O.S., with
     a +1.75D add O.U.
        Refitting into soft toric monovision lenses improved her comfort and wearing time, but the visual acuity at both distance and near was
     decreased. Her best-corrected soft toric monovision acuity, with Air Optix for Astigmatism (CIBA Vision), was 8.7/14.5 O.U., -3.50 -1.25 x
     180 (distance) O.D., -1.00 -2.25 x 010 (near) O.S. Claire’s distance visual acuity was 20/30 O.U., and her near visual acuity was 20/30 O.U.
        But, refitting with soft multifocal toric lenses restored both distance and near acuity. The final lens was the Proclear Multifocal Toric
     (CooperVision) 8.7.14.4. Claire was fit with a D lens (Distance center) on her left eye, -3.50 -1.25 x 180 “D” +1.50, and an N lens (Near
     center) on her right eye, -2.50 -2.25 x 010 “N” +1.50, resulting in a distance acuity of 20/20 O.U. and a near acuity of 20/25+ O.U.



contact lens evaluation during your                Consultative Prescribing:                         that is supported by the clinical
consultation. Today’s variety of                   Create a Nexus                                    findings. Usually, this form of con-
toric multifocals, hybrid multifo-                    The post-examination consul-                   sultative prescribing requires little
cals and a wide range of GP multi-                 tation is the opportunity to pull                 or no persuasion.
focals offer extensive opportunities               together the discovery in the case
to prescribe beyond the ordinary.                  history and the clinical findings.                Examples of Consultative
                                                   The word nexus means a substan-                   Prescribing
Soft Contact Lenses or CRT                                                        Our experts provided consulta-
                                                   tive connection. Your consultation
   While we all have varying                                                   tive prescribing examples similar
                                                   should create a connection between
opinions on the value of myopia                                                to the following. The key to each
                                                   the needs, wants and preferences
progression regulation, there                                                  example is a paraphrasing of the
                                                   made clear in the case history and
is substantial evidence that the                                               patient’s elicited need, want or
                                                   your treatment alternatives and rec-
modulation of peripheral retinal                                               preference, the clinical findings
                                                   ommendation. Clinical findings can
defocus through use of distance                                                that are relevant and a recommen-
                                                   be referenced to provide a basis for
center multifocal contact lenses                   your recommended treatment. dation that is connected to the case
or corneal reshaping with corneal                                              history report.
                                                      In each of the aforementioned
refractive therapy (CRT) lenses is                                                • “You reported that only 12 of
                                                   case examples, the practitioner dis-
efficacious.3-5                                                                your 16 hours of contact lens wear
                                                   covered a need, want or preference
   Reserve your judgment. CRT has                                              are comfortable. You are wearing
                                                   during the case history and con-
a long history of providing tempo-                                             brand X silicone hydrogel dispos-
                                                   nected it with a treatment option
rary therapeutic correction                                                          able lenses. I recommend that
for myopia, with and without                                                         we test you over the next 90
astigmatism. If, during your                                                         days with four different mate-
case history, you discover the                                                       rials and designs to see if we
patient’s preference for spend-                                                      can extend your comfortable
ing waking hours free of spec-                                                       wearing time.”
tacles or contact lenses and an                                                         • “You reported the inabil-
aversion to refractive surgery,                                                      ity to read in dim light. You
you have an opportunity to                                                           are currently using monovision
prescribe beyond the ordi-                                                           correction, and your exami-
nary! CRT patients are enthu-                                                        nation revealed uncorrected
siastic about and appreciative                                                       astigmatism. Your clinical
of their ability to function                                                         findings revealed a significant
correction-free during the day.                                                      astigmatism along with the
Further, there is anecdotal evi-                                                     need for bifocal correction. I
dence of resolution of dry eye                                                       recommend brand Y soft toric
symptoms previously reported Optical coherence tomography of an RGP scleral lens     multifocal lenses. The use of
by patients.                      and cornea demonstrates apical clearance.          multifocal lenses gives you the


26       REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
advantage of summation,                                                                               and there is a heightened
where you see better with                                                                             awareness for the costs
both eyes together than                                                                               of living and healthcare.
you do with each eye                                                                                  Even so, people consis-
separately.”                                                                                          tently demonstrate that
   • “You reported                                                                                    they don’t mind spending
difficulty seeing at all                                                                              money on the things they
distances and most                                                                                    really want. This is why
particularly, in the far                                                                              it is always best to recom-
distance. Your clinical                                                                               mend a treatment that has
findings support your                                                                                 the potential to improve
previous diagnosis of                                                                                 their life. Worst-case sce-
keratoconus, and your                                                                                 nario: Patients can say no
irregular astigmatism is                                                                              or put off following your
greater than your soft        CRT, the effects of which are seen on this corneal topography,          recommendation until a
lenses can correct. Your is under investigation for desirable peripheral defocus to                   later date.
work environment is           regulate myopia progression.                                                Prescribing in the best
dusty and dirty, con-                                                                                 interest of patients is pre-
traindicating corneal GP lenses. I         this method may prevent myopia              scribing to enhance the quality of
recommend scleral lenses, which            from progressing further.”                  their lives. If they accept your rec-
provide the benefits of your soft             • “You reported that your read-          ommendations and the treatments
lenses with regard to foreign body ing vision is adequate, but when                    satisfy their needs, wants or pref-
migration under your lenses, as            you drive, your vision is insuf-            erences, they will be enthusiastic
well as improved visual acuity.”           ficient; you remove your lenses             and will appreciate your care.
    • “You reported that your child        and drive with your spectacles.             Further, they will differentiate you
is active and dislikes wearing spec-       You also stated your preference             from other practitioners and will
tacles or contact lenses at school         for sharp distance vision and not           elevate extraordinary lenses over
and during sports. The clinical            wanting to wear spectacles in the           commodity lenses.                      RCCL


findings indicate a continued              evening. Your clinical findings
                                                                                       1. Legerton JA. Our two most powerful tools. Optometric
progression in myopia from last            revealed astigmatism, nearsighted-          Economics 1994 June.
year’s examination. I recommend            ness and presbyopia. I recommend            2. Lipson MJ, Musch DC. Synergeyes versus soft toric
                                                                                       lenses: vision-related quality of life. Optom Vis Sci. 2007
corneal refractive therapy, contact        the SynergEyes multifocal. The              Jul;84(7): 593-7.
lenses that are worn during sleep          rigid optics will provide clear dis-        3. Aller TA, Wildoset C. Bifocal soft contact lenses as a
and removed in the morning; they                                                                         control
                                           tance and near vision in each eye.” possible myopiaClin Exp treatment: a case report involving
                                                                                       identical twins.          Optom 2008 Jul;91(4):394-9.
will reshape the cornea and correct                                                    4. Cho P, Cheung SW, Edwards M. The longitudinal ortho-
                                                                                       keratology research in children (LORIC) in Hong Kong: a
your child’s vision for the entire         Don’t Second Guess                          pilot study on refractive changes and myopic control. Curr
day. In addition to not having to          Pocketbooks                                 Eye Res. 2005 Jan:30(1):71-80.
                                                                                       5. Walline JJ, Jones LA, Sinnott LT. Corneal reshap-
wear contact lenses or glasses dur-            Most would agree that Ameri-            ing and myopia progression. Br J Ophthalmol. 2009
ing the day, there is evidence that        cans today have less available cash, Sep;93(9):1181-5.


   Brian Chou, O.D., F.A.A.O., San Diego, Calif.
      “Justin,” a 21-year-old male Division I collegiate golfer, presented for a routine exami-
   nation wearing AirOptix Aqua Night & Day (CIBA Vision) 8.4 base curve -1.50D lenses
   O.U. He had no complaints aside from needing more contact lenses. Justin reported
   adhering to a daily removal regimen, and his visual acuity was 20/20+ O.U. Spherical-
   cylindrical over-refraction was plano - 0.50 x 085 yielding 20/15 O.D., and plano - 0.50 x
   095 yielding 20/15 O.S.
      Due to the patient’s high vision demands, I refit him into Extreme H2O 54% Toric Low         This fluorescein pattern shows a well-
   Cylinder lenses (Hydrogel Vision) -0.65 DC, with a base curve of 8.6, -1.50 sphere, 090         fit lens for overnight corneal refractive
   axis O.U., resulting in 20/15 O.U. with a correlated improvement in subjective vision.          therapy for myopia with or without
                                                                                                   astigmatism.



                                                                                       REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010        27
                            Biofilms:
                       A Look Inside
                          the Case
How clean are patients’ lens cases, and how often must they be replaced in order to
avoid biofilm buildup on lenses and cases?
By Michael Mayers, O.D., F.A.A.O.



W
          hat is a biofilm? How          shell protects pathogens on the                              Dr.
          does it form? Is it avoid-     inside while continuing to recruit                           Mayers is
          able? And, what con-           free-floating microorganisms to                              in private
sequences does it have regarding         add layers to the dome. The cycle                            practice
contact lens care education for our      continues as the biofilm matrix                              in Powell,
patients? These questions raced          becomes larger, making this com-                             Ohio.
through my mind the first time I         plex network of microorganisms                   He is the founder of
heard the term “biofilm.”                more difficult to kill.1                         Mayers Eye Solutions.
   With a thorough understanding            Planktonic cells are able to
of biofilm formation, we can bet-        adhere to medical device surfaces,
ter counsel patients in the proper       such as the polymer of the con-
techniques and schedules for case        tact lens material and the contact
cleaning and replacement.                lens case. In one study, 82% of
                                         the contact lens cases examined
All About Biofilms                       tested positive for pathogen con-
   A biofilm is a group or collection    tamination.2 We also know that the
of free floating microorganisms          growth of biofilm formation occurs
called planktonic cells that secretes    rapidly over the initial two hours
its own protein-polysaccharide           for S. marcescens and six hours
complex, creating an “outer shell,”      for P. aeruginosa.3 These become
or glycocalyx. I like to think of this   the anchor cells, making it easy
outer covering as the new Dallas         for other cells to adhere. At this
Stadium, with all the seats inside       “infant” stage, the biofilm is easy
as individual organisms. The outer       to eradicate because of its loosely


                                                                 REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010    29
connected network of cells. But,             case polymer formulations.                  the solution manufacturer pro-
once other cells build upon the                 Currently, there are three dif-          vides with its company name or
anchor cells, adherence between              ferent polymer plastics (polypro-           solution name stamped on the
them and the contact lens case               pylene, styrene and polyethylene)           case itself.
or lens surface becomes stronger.            that can be employed when cast-                With that said, the current ISO
The mature biofilm begins to                 ing a lens case. These polymers             14729 standards for evaluat-
produce a substance that has new             differ in rigidity and molecular            ing the efficacy of a contact lens
properties, making it more anti-             weight. Additives are usually               solution do not require testing
microbial resistant than individ-            mixed in to soften the polymers             with a contact lens case or any
ual planktonic cells.4 Subjects of           and give them their shape. For              contact lens material.8 These ISO
one study who failed to fully air            example, stearic acid softens               standards require testing against
dry their case more than doubled             the case, but if the concentra-             only five planktonic organisms
their risk of microbial keratitis.5          tion becomes too high, it will              in a test tube environment. These
Studies have found a strong cor-             bloom out onto the surface and              organisms are Staphylococcus
relation between the strain of               react with the preservative in the          aureus, Pseudomonas aeruginosa,
pathogen in the eye infection and            solution.7 When it reacts with              Serratia marcescens, Candida
the contact lens case pathogen.6             the preservative, it decreases the          albicans and Fusarium solani.9
Biofilms can flourish within a               efficacy of the solution. Contact           The current five organism strains
contact lens case—especially in              lens cases distributed and coined           used in ISO 14729 testing are cul-
that of a noncompliant lens wear-            as “flatpaks” may be made by a              tured in a lab and are considered
er (figures 1 and 2).                        plastic polymer plant in a very             less virulent than today’s real-
                                             cost-efficient manner, but the              world mutated organisms (i.e.,
Case Technology                              concentration of stearic acid in            clinical isolates).10 Acanthamoeba
   Are all cases created equal? To           these cases is unknown. Cases               is not part of the ISO testing;
answer that question, we would               typically made by a major con-              therefore, it is not required for
need to first ask: “Are all contact          tact lens solution manufacturer             solution manufacturers to chal-
lens solutions created equal?”               are tested for safety and effi-             lenge the efficacy of their solution
The answer to both: “No.” As                 cacy with their specific lens care          against this organism. Acan-
we all know, there are different             products, contact lens materials            thamoeba exists in two forms: an
formulations of contact lens solu-           or additional lens cleaners. So,            active trophozoite form that rav-
tions and different contact lens             instruct patients to use the case           enously consumes bacteria and a
                                                                                         “survival mode” cyst state that is
                                                                                         very difficult to eradicate because
                                                                                         of its double-layer cell wall.11 It
                                                                                         is important to mention that all
                                                                                         contact lens solutions pass cur-
                                                                                         rent FDA testing criteria against
                                                                                         the five standard ISO strains of
                                                                                         planktonic cells, but once these
                                                                                         solutions are tested against more
                                                                                         virulent biofilm strains, the effi-
                                                                                         cacy of the solution can change.
                                                                                         Polyquaternium-based disinfec-
                                                                                         tion solutions are more effec-
                                                                                         tive against both standard and
                                                                                         real-world clinical isolates strains
                                                                                         of Fusarium solani than PHMB-
                                                                                         based solutions.10 And, it was also
                                                                                         reported that polyquad/aldox and
                                                                                         hydrogen peroxide-based systems
1, 2. Note the rods embedded in the polymer matrix of the contact lens (left). A thick   maintained their efficacy against
biofilm of rod-shaped bacteria covers the surface of a lens case (right).                P. aeruginosa and S. aureus


30    REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010
                                                                    with the fresh        for preventing biofilm formation.16
                                                                    lens solution         But, two-step peroxide systems are
                                                                    residue, which        very cumbersome to employ, and
                                                                    continues to          most of our patients do not want to
                                                                    kill pathogens.       comply with a two-step system in
                                                                    This method           their contact lens care regimen. This
                                                                    reduced case          is probably why most peroxide sys-
                                                                    contamination         tems today are one-step systems that
                                                                    by 40% in one         begin to neutralize after 15 minutes
                                                                    study.13              and are almost completely neutral-
                                                                       But, silver        ized to sterile water 90 minutes
                                                                    nitrate lin-          after exposure to the catalase.17 But,
                                                                    ing has a few         the quick neutralization of a one-
3. Disinfection activity of contact lens solutions against          drawbacks. Any step system does not allow enough
planktonic bacteria.                                                patient with          contact time between hydrogen
                                                                    silver or metal       peroxide and Acanthamoeba cysts
biofilm-coated lotrafilon A lenses, allergies cannot use these cases as                   to effectively eradicate them.18 This
while the efficacy of PHMB-based a part of their care system. Silver                      is especially important for patients
solutions decreased (figures 3 and nitrate is a bactericidal agent only;                  who use peroxide systems in the
4).3 This is important because S.            it is not effective against Acantho-         United Kingdom, as the incidence
aureus and P. aeruginosa are                 moeba.14 In fact, one study demon-           of Acanthamoeba keratitis has been
some of the most cultured organ-             strated that when the silver-lined           reported to be 15 times higher in
isms from eye infections.12                  case and solution was overwhelmed            the United Kingdom than it is in the
    Recently, a manufacturer                 with bacteria, it had marked P.              United States.19
incorporated a silver nitrate lin-           aeruginosa biocidal activity, but had
ing in their contact lens cases in           minimal effects against S. aureus.15         Case Replacement and
an attempt to decrease or retard             A hydrogen peroxide-based solution Intervention
biofilm formation. Here’s how                is another alternative in contact lens           Tap water is filled with micro-
this works: silver nitrate is slowly         case technologies. These systems             organisms, which can increase
activated during the soaking cycle           require a catalase for neutralization        the likelihood of Acanthamoeba
of a contact lens solution and is            of the solution, which allows it to          keratitis. But, in 2007, most
ultimately dissolved by sterile              be non-toxic to the ocular surface.          of one study’s cohort—52%—
aqueous solution. The disinfec-              Two-step hydrogen peroxide disin-            used tap water to clean their
tion process can take up to 24               fection systems are the most effica-         cases, and only 20% of sub-
hours for silver nitrate to com-             cious at killing bacteria, fungi and         jects replaced their case at least
pletely become efficacious. Thus,            Acanthomoe-
PHMB or biguanide is still used to ba, because the
increase the disinfection proper-            peroxide soaks
ties of the solution and decrease            at a certain
potential adverse events. Compli-            concentration
ance with this care system differs           (usually 3%)
from conventional lens case com-             for four hours,
pliance because of the silver-lined          killing most
case. The manufacturer recom-                organisms.
mends emptying the case of old               One such
solution, rinsing it with new solu-          study demon-
tion and placing the caps tightly            strated that
back on the case, so the case will           a four-hour
not fully air dry after contact lens- 3% hydrogen
es have been removed from the                peroxide soak 4. Activity of solutions when tested against biofilm-laden
case. Capping the lens case tightly          received the         lotrafilcon A lenses. Note the decrease in disinfection efficacy
allows the silver ions to react              best marks           of PHMB based solutions.



                                                                             REVIEW OF CORNEA & CONTACT LENSES | APRIL 2010   31
annually.20 The following year,             appointment for an exam and fit-                          2. Gray TB, Cursons RT, Sherwan JF, Rose PR. Acantham-
                                                                                                      oeba, bacterial, and fungal contamination of contact lens
another study found that only               ting, have them bring in all their                        storage cases. Br J Ophthalmol.1995 Jun;79(6):601-5.
3% of South Florida municipal               lens cases from their house. You                          3. Szczotka-Flynn LB, Imamura Y, Chandra J, et al.
                                                                                                      Increased resistance of contact lens-related bacterial
water sources were contaminated             might be surprised how patients                           biofilms to antimicrobial activity of soft contact lens care
with Acanthamoeba, but of all               hoard their cases, and how many                           solutions. Cornea. 2009 Sep;28(8):918-26.
                                                                                                      4. Farber BF, Hsieh HC, Donnenfeld ED, et al. A novel anti-
actual Acanthamoeba keratitis               different contact lens case designs                       biofilm technology for contact lens solutions. Ophthalmol-
cases studied in Florida, 25% had           are available!                                            ogy. 1995 May;102(5):831-6.
                                                                                                      5. Edwards K, Keay L, Naduvilath T, et al. Risk factors for
evidence of Acathamoeba in the                 Tell your patients to throw away                       contact lens related microbial keratitis in Australia. Invest
water supply.21                             all cases that do not match the                           Ophthalmol Vis Sci. 2005;46: E-Abstract 92. Available at:
                                                                                                      http://abstracts.iovs.org/cgi/content/abstract/46/5/926.
   Remember, Acanthamoeba                   solution they’re currently using.                         (Accessed March 2010).
feeds off of bacteria, which is             Just as we are educating compli-                          6. McLaughlin-Borlace L, Stapleton F, Matheson M, et al.
                                                                                                      Bacterial biofilm on contact lenses and lens storage cases
why keeping a clean, bacteria-              ance with contact lens replace-                           in wearers with microbial keratitis. J Appl Microbiol. 1998
free case should potentially limit          ment schedules and contact lens                           May;84(5):827-38.
                                                                                                      7. Personal Communication. Ralph Stone. November 13,
Acanthamoeba growth.                        solutions, now is the time to take                        2009. American Academy of Optometry Meeting. Orlando,
   Caution patients never to let tap        action and educate our patients                           Fla.
                                                                                                      8. Saviola JF. Contact lens safety and the FDA: 1976
water come into contact with their          on biofilms and the importance of                         to the present. Eye Contact Lens. 2007 Nov;33(6 Pt
lenses, lens case or solution. With         good contact lens case compliance.                        2):404-9.
                                                                                                      9. ISO 14729. Ophthalmic optics – contact lens care
our consistent education efforts,                                                                     products – microbiological requirements and test methods
the percentage of those who                 The Value of Your                                         for products and regimens for hygienic management
                                                                                                      of contact lenses. 2001. Available at: www.iso.org/iso/
replace their case should increase          Recommendation                                            catalogue_detail.htm?csnumber=25382. (Accessed March
substantially. Also, patients can              We, as a profession, must still                        2010).
                                                                                                      10. Hume EB, Flanagan J, Masoudi S, et al. Soft
interrupt biofilm formation by              take great strides to prevent bio-                        contact lens disinfection solution efficacy: clinical
disinfecting their cases regular-           film formation in contact lens                            Fusarium isolates vs. ATCC 36031. Optom Vis Sci. 2009
                                                                                                      May;86(5):415-9.
ly—microwave the lens case for              cases. Contact lens solutions                             11. Johnston SP, Sriram R, Qvarnstrom Y, Roy S, et al.
three minutes with contact lens             should be tested with lens cases                          Resistance of Acanthamoeba cysts to disinfection in
                                                                                                      multiple contact lens solutions. J Clin Microbiol. 2009
solution in the case, which has             and lens materials, including                             Jul;47(7):2040-5.
been shown to completely kill all           silicone hydrogels. Newer, more                           12. Sherwal BL, Verma AK. Epidemiology of ocular
                                                                                                      infection due to bacteria and fungus. Available at: www.
pathogens while not affecting the           virulent clinical isolates should be                      jkscience.org/archive/volume103/original/ocular%20infec-
case shape.22 Microwave disinfec-           challenged when testing contact                           tion.pdf. (Accessed March 2010).
                                                                                                      13. Amos C. Clinical testing of the MicroBlock antimicro-
tion is performed by filling the            lens solutions and Acanthamoeba                           bial lens case. Optician. 2005;230(6008):16-20.
wells of the contact lens case half         should be considered in new dis-                          14. Weisbarth R, Gabriel MM, George M, et al. Creating
                                                                                                      antimicrobial surfaces and materials for contact lenses and
full with contact lens solution and         infection standards.                                      lens cases. Eye Contact Lens. 2007 Nov;33(6 Pt 2):426-9.
leaving the lid caps placed on the             But as of now, we know that                            15. Vermeltfoort PBJ, Hooymans JMM, Busscher HJ, et al.
                                                                                                      Bacterial transmission from lens storage cases to contact
receptacle but not screwed on to            some contact lens solutions have                          lenses—effects of lens care solutions and silver impregna-
avoid overpressure. Or, another             shown better efficacy against bio-                        tion of cases. J Biomed Mater Res B Appl Biomater. 2008
                                                                                                      Oct;87(1):237-43.
method: Have patients empty                 films. So, remind your patients                           16. Wilson LA, Sawant AD, Ahearn DG. Comparative effi-
out the case, then completely fill          that combining different medical                          cacies of soft contact lens disinfectant solutions against
                                                                                                      microbial films in lens cases. Arch Ophthalmol. 1991
it with fresh new multipurpose              devices, such as cases, lenses and                        Aug;109(8):1155-7.
solution during the day (without            solutions, can be a very complex                          17. Ngo W, Heynen M, Joyce E, Jones L. Impact of protein
                                                                                                      and lipid on neutralization times of hydrogen peroxide care
lenses) for storage. This creates a         undertaking, and even though                              regimens. Eye Contact Lens. 2009 Nov;35(6):282-6.
24-hour continuous disinfection             they seem extremely safe most of                          18. Hughes R, Kilvington S. Comparison of hydrogen peroxide
                                                                                                      contact lens disinfection systems and solutions against Acan-
process and potentially prevents            the time, many risks still exist.                         thamoeba polyphaga. Antimicrob Agents Chemother. 2001
any early biofilm formation.                Finally, when you are prescribing                         Jul;45(7):2038-43.
                                                                                                      19. Kilvington S, Gray T, Dart J, Morlet N, et al. Acanthamoeba
Don’t forget, no matter how much            the correct contact lens solution,                        keratitis: the role of domestic tap water contamination in the Unit-
your patients disinfect their cases,        lens material and lens case, write                        ed Kingdom. Invest Ophthalmol Vis Sci. 2004 Jan;45(1):165-9.
                                                                                                      20. Morgan, PB. The Science of Compliance. Eurolens Research.
make sure they replace their lens           a prescription for each medical                           The University of Machester.
case every three to six months per          device employed. After all, isn’t                         21. Shoff ME, Rogerson A, Kessler K, Schatz S, Seal DV. Preva-
                                                                                                      lence of Acanthamoeba and other naked amoebae in South
FDA recommendations.23                      the case and solution selection                           Florida domestic water. J Water Health. 2008 Mar;6(1):99-104.
                                            just as complex and important as                          22. Hiti K, Walochnik J, Faschinger C, et al. Microwave treatment
                                                                                                      of contact lens cases contaminated with Acanthamoeba. Cornea.
Patient Education                           a topical or oral drug?                RCCL
                                                                                                      2001 Jul;20(5):467-70.
  When established contact                  1. Zegans ME, Shanks RM, O’Toole GA. Bacterial biofilms
                                                                                                      23. FDA. Focusing on contact lens safety. Available at: www.
                                                                                                      fda.gov/forconsumers/consumerupdates/ucm048893.
lens patients call to schedule an           and ocular infections. Ocul Surf. 2005 Apr;3(2):73-80.    htm. (Accessed March 2010).



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