OHP II Midterm 1 Notes _Jackie V_ by gegouzhen12

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									                                                                                                    OHP Midterm 1 Notes 1

Gonioscopy, Fundus Lens, 3-Mirror, SL-OCT

  I.   Gonioscopy: procedure used in evaluation of the peripheral AC angle
          a. Characteristics
                    i. not directly visible through standard biomicroscopy
                   ii. www.gonioscopy.org
                 iii. evaluation of the narrow AC angle prior to dilation
                  iv. ddx of angle closure
                   v. ddx of open angle glc (AC is normal, no pigment, but changes in angle is being affected)
                  vi. eval of iris contour changes
                 vii. r/o NVI (pressure can increase quickly and may lose vision)
                viii. hx of blunt trauma
          b. Contraindications
                    i. hyphema (due to neovascularization of iris (older), trauma (younger) and tumor)
                   ii. recent refractive surgery (3-6 months)
                 iii. compromised corneas
                  iv. perforated eyes
                   v. lacerations
          c. Other uses
                    i. retinal 3-mirror evaluation
                   ii. laser trabeculoplasty
                 iii. compression gonioscopy (when pressure applied iris bunches up reduction
                       of outflow of aq so it builds up pressure and closes it up)
                           1. breaking angle closure attack by pushing on central cornea to displace
                                liquid into peripheral AC to break the contact between cornea and iris
                                (only can be done with small lens that touches cornea only, not the
                                limbus)
                           2. evaluation of synechiae (peripheral AC): if it looks like cornea is
                                attached you can test it
          d. Methods
                    i. Direct: direct viewing with light source and viewing microscope using Koeppe Lens
                           1. magnifying lens is put on eye and use hand held slit lamp device to look right into the eye




                    ii. Indirect: employs mirrors mounted into a contact lens




           e.   Types of Lenses (need fluid because hard to see through air)
                    i. 3 mirror lenses: fluid (GenTeal and Celluvisc) vs no-fluid lenses
                           1. Characteristics
                                    a. more versatile
                                    b. clearer views
                                    c. better for blepharospasm
                                    d. adheres to eye on central axis
                   ii. Goldmann 3 mirror lens (rocket shaped lens)
                           1. Hruby lens: 64 D lens
                                    a. central viewing lens
                                                                                                      OHP Midterm 1 Notes 2

                                  b. upright image
                          2. Apical mirror: 59 degrees lens
                                  a. bullet or thumbnail shaped (at the top)
                                  b. angle viewing and ora serrata
                          3. Peripheral mirror: 67 degrees
                                  a. square mirror (middle)
                                  b. peripheral retinal evaluation
                          4. Equatorial mirror: 73 degrees
                                  a. trapezoid mirror (base)
                                  b. equatorial retina evaluation
                 iii. 4 mirror lenses (can see folds and ripples of Descemet’s as you push in)
                          1. Types
                                  a. Sussman: no handle
                                  b. Posner: stick handle
                                  c. Zeiss: Unger holding fork
                                  d. G4: with a flange
                          2. Characteristics
                                  a. compression gonio
                                  b. uses little or no fluid
                                  c. rapid assessment of the angle
                                  d. less traumatic to the eye
                                  e. requires more dexterity
 II.   Types of Gonioscopy
          a. Indentation/Compression Gonioscopy
                   i. Characteristics
                          1. done with corneal gonio lenses (4 mirrors)
                          2. assess if appositional closure or PAS present
                          3. directs aq towards the peripheral AC and pushes the peripheral iris
                             back to view the angle
                          4. can be used to break ACG attack, lower IOP




           b. Dynamic Goniosscopy
                    i. allows for a better view over a very convex peripheral iris
                   ii. tilt or slide lens towards the angle being viewed or have patient look into the mirror
                       (not pushing on the lens)
                             1. the mirror is opposite of where the angle is
                             2. if looking at superior angle, the mirror is actually on the bottom
III.   Structures to be viewed (I Can’t See This Sucka)—Work from the pupil to the apex
           a. Iris: most posterior structure
                                                                        OHP Midterm 1 Notes 3

b. CB: may not be seen if obstructed by iris
   processes or with iris bow
         i. color: ranges from light grey to light
            brown
                 1. charcoal grey in darker irides
        ii. width: 0.5 mm
                 1. wider may indicate angle
                      recession
       iii. visibility: may be obscured by iris
            processes or iris
c. Scleral spur: fibrous ring that attaches the CB
   to TM
         i. color: whitish band
        ii. appearance: radial ring that may be
            obscured by iris or iris processes
d. TM: filtration area of the angle very variable
         i. clinical pearl: iris processes insert into TM
        ii. structure
                 1. pigmented (posterior)
                          a. filtering potion of the angle
                          b. Schlemm’s canal (next to 55)
                                    i. visible when episcleral venous
                                       pressure increases
                 2. non-pigmented (anterior)
       iii. Pigment in the TM




                 1. densest pigment area is inferior due to gravity
                 2. pigmentatation does not occur before puberty
                 3. increases in pregnancy, age and iris colors
                 4. other related changes
                        a. pigment dispersion syndrome
                        b. previous injuries or surgeries
                        c. exfoliation
                        d. open angle glaucoma
                        e. previous uveitis
                 5. pigmentation grading system (3-4+ rare)
                        a. 0 = granular, fine, gray color
                        b. trace
                        c. 1+ = scattered pigment/slightly brown
                        d. 2+ =definitely visible brown pigment
                        e. 3+ = dense pigment band
                                                                                                 OHP Midterm 1 Notes 4

                                   f.      4+ = pigment on the iris, SS, CB
                                           (extremely thick and dense)
           e. Schwalbe’s Line: termination of Descemet’s
                     i. anterior limit of the angle wall
                             1. optic section angled across cornea
                             2. junction of anterior and posterior cornea
                                 lines
                    ii. appearance (3 bands instead of 2 bands)
                             1. thin white glistening line
                             2. acts as a “shelf” (pigment may collect
                                 inferiorly)
                                      a. Sampaolesi’s line: a wavy line of
                                           pigment seen in exfoliation
                                           patients (usu inferior)
                                                 i. ddx between TM and
                                                     Sampaolesi’s line: rotate
                                                     the mirror (if pigment is
                                                     sitting on bottom, the line
                                                     will disappear, if TM the
                                                     line will be continuous)
                             3. 15% of eyes have it anterior displaced
                                 posterior embryotoxon
                                      a. may be glaumatous because a lot
                                           fo iris processes in the eye
                                      b. looks like arcus but it’s in the
                                           front part of eye
                                      c. easiest to see at 4:00 and 8:00
                                      d. looks limbus is easiest to see at 6:00
           f. Common “sightings” in the angle
                     i. iris processes
                    ii. Sampaolesi’s line
                   iii. Blood in Schlemm’s canal (may see it because you are reducing venous outflow through vortex veins-
                         backflow into blood channels Schlemm’s canal is filled with blood that backs upshould pull
                        back on lens)
                   iv. Unwanted “guests”
                             1. synechiae
                             2. neovascularization
IV.   Is the eye safe to dilate?
           a. IOP: will it spike?
                     i. reduced aq outflow
           b. Angle: will it close
                     i. who is most likely to close
                             1. moderate to high hyperopes
                             2. phacomorphic lens changes
                             3. shallow AC
                    ii. when will it close
                             1. mid dilated stage
                                                                                                      OHP Midterm 1 Notes 5

 V.    Grading
          a. Biomicroscopic angle grading =Van Herrick
                  i. optic section placed at 60 degrees; focused at limbus
                 ii. ratio of width of peripheral AC to width of cornea
                iii. 1:1 = wide open
                iv. ¼:1 = warrants gonioscopy in some cases
          b. Gonioscopy grading scale= Becker-Shaffer
                            Grade            Most Posterior Structure Visible
                               4             Ciliary body
                               3             Scleral Spur
                               2             Anterior TM
                               1             Anterior TM/Schwalbe’s line
                               0             No visible structures

VI.    Risk for angle closure
           a. TM without iris brow: slight risk
           b. TM with iris bow: somewhat risky (associated with shallow angle)
           c. ½ TM without iris: risky
           d. ½ TM with iris bow: very risky
           e. Schwalbe’s line: extremely risky
VII.   Procedure
           a. perform after tonometry
           b. select lens: 3 or 4 mirror
           c. disinfect the lens
           d. select cushioning solution
                     i. some lenses are no fluid
                    ii. celluvisc
                   iii. goniosol
           e. fill the lens about 2/3 full (no bubbles)
           f. anesthetize the eye
           g. position patient so they are centered vertically in the slit lamp (would rather have them lower than higher)
           h. prepare slit lamp
                     i. light housing at 0 degrees
                    ii. low mag
           i. identify which angle to be viewed and position lens in appropriate position
           j. lens insertion
                     i. control the lids
                    ii. insert into lower fornix and rotate onto eye
                   iii. hold firmly in iplace
           k. lens insertion
           l. Angle Assessment
                     i. identify location of bullet mirror
                    ii. focus and then increase mag
                   iii. rotate beam so it is perpendicular to angle
                   iv. identify the following
                             1. most posteriors structure
                             2. grade of pigment in TM
                             3. iris approach into angle
                                      a. flat
                                      b. moderate
                                                                                                        OHP Midterm 1 Notes 6

                                          c. bowed
                                4. any angle anomalies
             m. rotating the lens: apply light pressure and twist with 2 hands
             n. lens removal
                       i. patient can look up and blink
                      ii. have patient look nasally and then put direct pressure at edge of the lens through the lower eyelid
                     iii. if lens is fitted tightly, then use the lower lid and push it at the lens will break the seal
             o. irrigate the eye well if Goniosol is used
VIII.   Documentation
             a. which eye
             b. most posterior structure viewed
             c. amount of pigmentation in TM (0-4+)
             d. iris approach into angle (flat, mod, bowed)
             e. angle anomalies
 IX.    Troubleshooting
             a. 3 mirror: Can’t see anything?
                       i. lens tilt
                      ii. wrong mirror
                     iii. bubble
                     iv. steamy view = no fluid in lens
                      v. iris bowing
                                1. could the angle be closed
                                          a. need to tilt lens
             b. 4 mirror: Can’t see anything
                       i. lens is not centered
                      ii. lens is angled
                     iii. pushing too hard
                                1. folds in Descemet’s
  X.    Billing
             a. Gonioscopy: 92020
                       i. OU
                      ii. 1x/year
                     iii. can code with a 92012
                     iv. need to have an associated code
                                1. narrow angles
                                2. glc suspect
                                3. glc
 XI.    Examples of Angle Pathology
             a. Angle Assessment
                       i. Van Herick measures “apparent” depth
                                1. iris appears closer
                                2. typically underestimating angles (Ali, Khadem,
                                    Sawamura)
                      ii. gonioscopy tells you what is open, not what is closed
                                1. “creeping angle closure”
                                2. are we looking in the right area?
             b. Angle closure: most often a result of pupil block
                       i. r/o secondary causes
                      ii. pupil in mid-dilated stage and aq builds up pressure behind iris
                     iii. iris is pushed against the angle and TM outflow is obstructued
                                                                               OHP Midterm 1 Notes 7

                1. 30% of acute cases are preceded by intermittent
                   attacks
                2. IOP can spike up sharply
      iv. who is at risk?
                1. small corneal diameter
                2. shallow AC
                        a. 1.8 mm central AC depth
                3. thick lens
                4. steep anterior lens
                5. short axial length
c. Chronic Angle closure
        i. may be missed as the angle slowly closes
                1. formation of peripheral synechaie
                2. can occur 360 or in superior angle first
       ii. gonio must be performed in the dark
      iii. evaluate the “corners”
      iv. avoid excessive lens tilt
       v. anterior seg OCT
d. Plateau iris




e.   Pigment Dispersion Syndrome: iris is back bowing and rubs zonules
           i. “Classic Triad”
                  1. Krukenberg’s spindle: 1-2 mm in width, 3-6 mm in height
                           a. (-) finding for Krukenberg’s to r/o glaucoma
                  2. mid-peripheral iris transillumination defects
                  3. dense pigment in TM
          ii. pigment on anterior segment structures
                  1. iris, peripheral lens (Schele’s or Zentmeyer’s line)
        iii. peripheral iris concavity
         iv. pigment showering-post dilation
          v. IOP may or may not be elevated
         vi. findings
                  1. Sampaolesi’s line
        vii. dense pigmentation within the TM
f.   Angle recession




g. Peripheral Anterior Synechiae; pupils will look irregular in sha
                                                                                                       OHP Midterm 1 Notes 8

                     i. Etiology: broad based or focal attachments from iris to the cornea
                    ii. Causes: uveitis, neovascular glc, injury, previous intraocular surgery, chronic or intermittent angle
                        closure




            h. Neovascularization
                       i. hyphema in an olde rpatient
                      ii. diabetes, carotid disease, hx of vein occlusion
                               1. need to put (-) NVI with every diabetic patient
                    iii. find buds appear at pupillary margin
                               1. detectable with FAG 1 month before clinically visible
                     iv. extrastromal extension across iris
                      v. blood vessels cross over sclera spur
                     vi. broad based synechiae
                    vii. angle closure
                               1. inferior angle is the last to seal
                               2. can occur over days, weeks, months
            i. Blood in Schlemm’s Canal
                       i. excessive pressure from gonio lens
                      ii. increased episcleral venous pressure
                               1. look for engorged episcleral veins
                                       a. cavernous sinus fistula
                                       b. thyroid dz
                                       c. Sturge-Weber
                    iii. Low IOP
            j. Increased episcleral venous pressure
XII.    Validity of Anterior Segment OCT
            a. Studies compare Visante and UBM or Gonio
                       i. excellent correlation to gonioscopy
                      ii. 100% sensitivity, 96% specificity for detecting occludable angles
                    iii. equal to that of UBM
                     iv. identification of occludable angles with gonio
                               1. found 86-90% of angles were closed or occludable compared to gonio
            b. parameters in dim vs light
                       i. all angles showed narrowing under dim conditions
XIII.   Retinal evaluation with 3 mirror fundus lens
            a. magnified stereoscopic view of peripheral fundus
            b. disadvantages (lens insertion and cushioning agent)
            c. protocol (same as gonio except patient is dilated, SCAN through the entire mirror)
            d. Mirrors Utilized
                       i. Bullet mirror (59 degrees): visualize ora
                      ii. Square mirror (67 degrees): visualize anterior equator to periphery
                    iii. Trapezoidal mirror (73 degrees): visualize the equatorial retina
                     iv. Hruby lens: visualize the posterior pole
                                                                                        OHP Midterm 1 Notes 9

XIV.    Review of Fundus Biomicroscopy
           a. allows for a stereoscopic view of posterior semgnet
           b. image is real, inverted and reversed
           c. lenses: 60, 78, 90, Superfield, Super 60, 100
           d. keys: working distance, stability and making fine adjusgments
           e. procedure
                      i. parallelepiped w/ moderate illumination, and low
                         magnification
                     ii. pull slit lamp to the back
                   iii. have patient fixate on right/left ear
                    iv. keep your hand stable (rest on chek)
                     v. slowly push joystickforward
                    vi. look for ornage reflex
                   vii. ON should come into view
                  viii. assess the nerve and then scan along the superior/inferior
                         arcades (1-2 DD beyond macula)
                    ix. scan the macula list
                     x. utilize red-free to assess the RNFL
                    xi. can assess the vitreous



Lacrimal System Evaluation Foreign Body Removal

   I.   Dry Eye Evaluation
            a. Clinical Hx
            b. Symptom questionnaire
                    i. dry eyes, itching, red eyes
            c. TBUT with NaFl
            d. Ocular surface staining with NaFl
            e. Schirmer test
            f. Lid and Meibomian gland morphology
            g. Meibomian gland expression
            h. Special testing: Fluorimetry, interferometry, osmolarity
  II.   Vital Dyes
            a. Sodium Fluorescein (don’t use Fluress because it’s too thick for TBUT)
                    i. Purpose
                             1. penetrates cornea through epithelial defect
                             2. evaluates integrity of the cornea
                             3. “topography”
                   ii. Clinical Evaluations
                             1. ctls evaluation
                             2. corneal and conjunctival dz
                                     a. abrasions
                                     b. H. Simplex keratitis
                                     c. recurrent erosions
                                     d. dellens
                             3. tear film evaluation
                             4. reduced tear prism to evaluate how big it is
                                                                                        OHP Midterm 1 Notes 10

                          a. have people close their eyes and lean back so that a pool of fluorescein pooling
                             between the lids
               5. PEE = “punctuate epithelial erosions” better used than SPK because that’s keratitis
                    (suggesting an inflammation)
      iii. Procedure
               1. wet fluorescein strip
               2. fixate patient’s eyes upward, apply strip inside lower lid
               3. control eyelids
               4. have patient blink several times to distribute dye
               5. evaluate anterior seg with cobalt blue filter (slit lamp or burton lamp)
               6. enhance with yellow Wratten #12 filter if using it on the conjunctiva (normally, hard to see on
                    conj with fluorescein)
      iv. Appearance
               1. areas of highly fluoresced areas indicate defects or depressions
               2. areas of darkness or non-fluoresced areas indicate uneven distribution of tears or elevations
b. Rose Bengal
        i. Purpose
               1. stains epithelial surfaces that are deprived of mucin protein protection, exposed epithelial cell
                    membranes, mucous (protective effect of the TF)
               2. useful in patients with dry eyes
       ii. Clinical Applications
               1. dry eye (K. Sicca)
               2. filamentary keratitis
               3. herpes dendritic keratitis
      iii. Procedure
               1. available in strip form (also solution, but we use strip form)
               2. apply strip same as fluorescein strip
                        a. does not come off as easy as fluorescein, so you will need to put drop of saline to sit
                             on the strip for 5-10 seconds so that the fluid can pull dye out of strip
                        b. will sting up to a minute esp in dry eye patients
               3. white light or red-free (green makes it look more purple)
      iv. Appearance: defects indicate a reddish appearance indicating the collection of the stain by the
           devitalized cells
       v. Vam Bijestervald Grading scale: 3.5 or greater in 1 eye




c.   Lissamine Green
          i. Purpose
                 1. similar to Rose Bengal
                 2. less irritation than Rose Bengal
                 3. easier to visualize with conjunctival injection
                 4. does not stain mucous
         ii. Clinical Applications
        iii. Procedure
                 1. application is similar for all vital dyes (stays on eyelids)
                 2. wait 1-4 minutes
                 3. use low to mod lighting
                                                                                                    OHP Midterm 1 Notes 11

                 iv. Appearance
                          1. available in strip form
                          2. staining of dead and devitalized cells turns green
                          3. filters for viewing dyes
                                  a. Wratten #25 filter (orange filter)—lissamine
                                  b. Wratten #12 filter (yellow filter)—fluorescein
          d. TBUT
                   i. Purpose: measures mucin layer stability
                  ii. Procedure
                          1. apply unpreserved solution to a fluorescein strip
                          2. gently touch to patient’s tear meniscus
                          3. have patient blink several times and wait 30-60 secs
                          4. adjust slit lamp to diffuse beam with cobalt blue illumination
                          5. instruct patient not to blink and look straight ahead
                          6. count time until black spots of lines appear in TF, if blink occurs before this is considered
                               TBUT
                          7. repeat procedure several times to ensure reliability
                          8. blinking stops the test
                          9. calculate the mean for 3 trials
                 iii. Interpretation: abnormal = < 10 seconds
                 iv. Non-invasive TBUT
                          1. Keratometer
                          2. No vital dyes
                          3. Look for distortion of mires
                          4. Normal = > 10 seconds
                  v. What influences TBUT?
                          1. Decreases TBUT: ointment, preservatives, anesthesia, estrogen phase of menstrual cycle
                          2. Increases: AT
                          3. No effect: temperature and humidity
                 vi. Ocular Protection Index (OPI)
                          1. TBUT/Time between blinks in sec
                                  a. OPI <1  risk for ocular surface damage
                                  b. OPI >1  patient is not at risk
                          2. problem is measuring interblink time
III.   Lacrimal Secretion tests
          a. Schirmer Tests
                   i. Schirmer Test I (without anesthetic)
                          1. Purpose
                                  a. measures reflex and basic secretions
                                  b. maximum amount of TEAR production
                                  c. moderate to severe KCS
                          2. Procedure
                                  a. 5 cm paper strip is folded at notch and placed within the lower cul-de-sac near the
                                       outer 1/3 of the lid (nearest outer canthus—lateral )
                                            i. want to put it lateral so that it doesn’t scratch the cornea and away from the
                                                limbus
                                  b. dim lights and have patient blink normally
                                  c. after 5 minutes remove strips and measure amount of wetting with a mm rule from
                                       notch
                          3. Interpretation
                                                                                        OHP Midterm 1 Notes 12

                         a. 5 mm or less of wetting-abnormal
                         b. 5-10 mm is mild to moderate KCS
                         c. >10 mm = normal
                4. Influenced by: anesthetic, temperature, humidity, evaporation
b. Jones Basal Secretion (with anesthetic)
        i. Purpose: basal tear secretion, evaluation of the minimal amt of tear secretion, suspected mild KCS or
           ctls dry eye
       ii. Procedure
                1. prior to placement of Schmir strips one drop of topical anesthetic is placed in each eye
                2. wait approx 30 sec-1 min and blot the inferior cul-de-sac with either a cotton-tip applicator or
                    Kleenex to remove excess anesthetic and reflex tears
                3. continue as in the Schirmer test
      iii. Interpretation: abnormal = ≤ 5 mm
c. Short Basal Secretion Test
        i. identical to that of the basal secretion test, however, strips are removed after 1 minute
       ii. results are multiplied by a factor of 3 to extrapolate to a 5 minute value (not multiplied by 5)
      iii. interpretation of these results are same as Schirmer and Basal Secretion Test
d. Schirmer II
        i. Purpose: measures reflex secretions
       ii. Procedure
                1. instill topical anesthetic in each eye
                2. wait 30 seconds to 1 minute and remove excess tears from inferior cul-de-sac
                3. place strips in both eyes
                4. using a cotton tipped applicator, irritate the nasal mucosa for approx 10-15 seconds
      iii. Interpretation: <10 mm of wetting strip after 2 minutes suggests impaired reflex tearing
e. Sno-strips
        i. Purpose: same as Schirmer strips
       ii. Procedure
                1. perform same as Schirmer except place strip in each eye and wait until 10 mm are wet with
                    tears
                2. measure time period from insertion of strip to achieved 10 mm wetting
      iii. Interpretation
                1. 3-5 minutes: sufficient secretion
                2. 5-10 minutes: borderline
                3. >10 minutes: insufficient
f. Phenol Red Thread
        i. Indications: measures basal tear secretion
       ii. Procedure
                1. special cotton thread impregnated with phenol red
                2. placed in lower lateral lid margin
                3. 15 secs per eye
                4. less irritation than Schirmer
      iii. Interpretation: normal = 9-18 mm
g. Lactoferrin/Lactoplate (not practical)
        i. Purpose
                1. measures level of lactoferrin in the tears
                2. lactoferrin level indicates lacrimal gland sensitivity
                3. lactoferrin levels highly correlated with tear lysozyme (anti-microbial)
       ii. Procedure
                                                                                                     OHP Midterm 1 Notes 13

                            1. using forceps, place filter paper disc in inferior fornix and allow time of sufficient wetting
                                 (approx 5 min)
                            2. remove disc and place on lactoplate reagent pad
                            3. after 2-3 days measure size of precipitate ring with the template provided and convert into
                                 mg/ml
                  iii. Lactoplate (tear quality test)
                            1. designed to measure levels of lactoferrin, a tear protein
                            2. lactoferrin level is an indicator of lacrimal gland secretory activity
                            3. Interpretation
                                     a. average lactoferrin level = 1.4 mg/ml
                                     b. levels <0.9 mg/ml are considered to be abnormal and suggestive of insufficient
                                          lacrimal secretory acvitity
                  iv. Lactocard (touch tear microassay)
                            1. lactoferrin analysis of TF
                            2. more accurate at determining the presence of aq deficiency
                            3. results in 10-15 minutes
                            4. accuracy is comparable
IV.   Punctal Occlusion (collagen plugs)—dx test NOT treatment because collagen will dissolve over 5-10 days
         a. Purpose: help increase time that tears remain in contact with the eye by blocking tear drainage (reduce
              lacrimal outflow to see if there is a difference)
         b. Procedure
                    i. Anesthetize the punctum with topical drops, if needed
                            1. Put it on a cotton-tip applicator and place over puncta, then have them squeeze to get the
                                 anesthetic down
                   ii. Evaluate size of puncta to use appropriate size implant (0.2-0.5 range)—average is 0.3
                  iii. Lightly grasp end of a collagen implant with sterile forceps
                  iv. Instruct patient to look up and away from forceps
                   v. Implant may be inserted behind the biomicroscope or in free space with aid of magnifying loupe
                            1. need to place it at an angle, not straight down
                  vi. Place the implant into puncta and quickly push the tip of plug until it is below surface of lid margin
                            1. plug will quickly swell so there are only a couple of seconds to complete the procedure
                            2. implant should be inside the canaliculus so that there is less chance for extrusion
                            3. patient should be instructed to avoid rubbing their eyes
                            4. patient returns in 7-10 days for followup
                            5. patient will say that eyes feel better if the plug works a week later, they will have
                                 symptoms again (so need to ask how they feel a couple of days after)
         c. Interpretation
                    i. Re-evaluate the patient in approximately 1 week (inserts dissolve in 7-10 days)
                   ii. If significant improvement in S/S, consider more LT occlusion therapy such as silicone plugs or
                       punctual cautery
V.    Lacrimal Drainage tests
         a. Fluorescein Disappearance Test
                    i. Procedure
                            1. Sodium fluorescein is instilled into the patient’s eye (2 strips)—Not fluress
                            2. after 5 minutes, the inferior cul-de-sacs are examined to determine the amount of dye
                                 retention in the lacrimal lake
                            3. dye retention is graded on a 1+ to 4+ scale
                                     a. 1+ = little or no dye retention
                                     b. 4+ = maximum retention (problem with tear drainage)
                            4. asymmetry or prolonged presence suggests poor drainage
                                                                                      OHP Midterm 1 Notes 14

      ii. Interpreation
               1. 2 key things: look to see if the tears are draining out of eye and how dense/dark is the
                    fluorescein
                        a. if no change in fluorescein not draining out ( no dilation of tears)
                        b. if it becomes a smaller amount/more dilute = good drainage
b. Jones #1 (primary dye test)
       i. Procedure
               1. sodium fluorescein is instilled into the patient’s eyes
               2. after 5 minutes, dye should appear under the inferior turbinate in the nose
                        a. can be retrieved with a cotton tipped applicator
                        b. may require more time with older patients (10 minutes)
               3. may be enhanced with a Burton lamp or having the patient blow their nose
               4. if dye is visible or retrieved then the test is noted as being positive
               5. if no dye is recovered, perform Jones #2
c. Jones #2 (dilation and irrigation)
       i. Procedure
               1. the lacrimal drainage system is dilated and irrigated
               2. functional block: if dye does not appear with Jones No 1, but is detected with the Jones No.
                    2
               3. anatomical block: if no dye appears with Jones No 1 or No 2
                        a. will happen if fluid expressed through the opposite puncta blockage is distal to
                            common canaliculus
                        b. if plunger doesn’t move and no fluid expressed through opposite puncta or is
                            regurgitated thorugh same puncta, then blockage is proximal to common canaliculus
                            (closer to you)
                        c. irrigating through inferior puncta
                        d. diagrams




d. Punctal Dilation
       i. Purpose
               1. mechanical enlargement of the lacrimal puncta
               2. procedure usually involves the lower puncta
                       a. upper puncta may also be dilated
               3. instrument: lacrimal dilators
      ii. Procedure
               1. topical anesthesia is instilled, usu 2-4 drops per eye
               2. deeper anesthesia achieved by soaking cotton-tipped applicator with anesthetic and placing it
                   over lacrimal puncta for several minutes
               3. lacrimal dilator is placed vertically into the puncta and gently rolled between the thumb and
                   index finger (make sure you go right direction and make ½ directions)
                       a. after 1-2 mm insertion, the probe is re-oriented horizontally and the forward motion
                            is continued while applying temporal pressure on the lid
                       b. increasingly large dilators can be used to insure adequate dilation
                       c. after approximately 30 minutes, the puncta will return to its original diameter
                                                                                                  OHP Midterm 1 Notes 15

          e.   Lacrimal Irrigation
                    i. Purpose: irrigating solution (usually saline) is flushed through the lacrimal excretory system to
                       evaluate its integrity
                   ii. Procedure
                           1. dilation usually precedes irrigation to ease insertion of the irrigating cannula
                           2. a 23 gauge cannula is inserted vertically for 2 mm, then is tipped 15” below horizontal plane
                           3. stretch the lower lid temporally
                                     a. cannula may then be inserted until it meets the wall of the lacrimal sac approx 8 mm
                                         nasally
                           4. saline or fluorescein is irrigated into canaliculus (approx 1 cc)
                  iii. Interpretation
                           1. if pressure is applied to syringe and drainage system is open, the patient may cough or taste
                               salt in throat
                                     a. indicates a functional block
                           2. if drainage system is blocked, resistance will be felt when pressure is applied to the plunger
                               do not force it




          f. Lacrimal Probing
                  i. Purpose: probing of lacrimal drainage system indicated when irrigation reveals a blockage
                 ii. Procedure
                         1. repeat topical anesthesia
                         2. lacrimal probe is inserted into puncta and canaliculus (Bowman probe used)
                         3. if resistance to the probe felt approximate, the blockage site by measuring length of probe
                              which is inserted
                iii. Interpretation
                         1. a “hard stop” noticed when the probe contacts the medial wall of the lacrimal fossa (normal)
                         2. a “soft stop” is noticed when probe hits an obstruction or collapses the lacrimal sac against
                              the lacrimal fossa (abnormal)
VI.   Foreign Body Removal
         a. Case History
                  i. what happened?
                 ii. when did it happen?
                iii. where did it happen?
                iv. what symptom does the patient have?
                 v. was the patient wearing any eye protection at the time of injury?
                vi. has any emergency tx already been given?
         b. VA
                  i. important both for patient care and medicolegal reasons
                 ii. take BCVA
                iii. use a pinhole if pt not wearing habitual Rx
                iv. if patient has severe blepharospasm, try instilling topical anesthetic
         c. SLE
                  i. need to dark adapt yourself
                 ii. use a broad beam at low mag to get an overall view and locate the fb
                iii. use optic section to find out how deeply the fb has penetrated
                                                                                         OHP Midterm 1 Notes 16

                 1. if fb is located along the visual axis and is in Bowman’s membrane or deeper (ie: will leave a
                      scar), consider referral to an ophthalmologist
       iv. check for ciliary flush and use a conic section at high mag to check for cells and flare in the AC
            indicating secondary uveitis
                 1. small parallelpiped is the best
        v. instill fluorescein and look for areas of staining
       vi. evert the lid and check for the presence of fb, esp important if fb tracks are noted
d. Metallic Foreign Body
         i. if a corneal perforation is suspected…
                 1. perform a Seidel test
                          a. apply fluorescein heavily to the site of fb entry
                          b. aqueous oozing thorugh a perforation will dilute the fluorescein
                 2. reduced IOP is another indication of perforation
                 3. do a DFE to check of the presence of intraocular fb
                 4. orbital X-rays may be necessary to locate metallic intraocular fb (not an MRI)
                 5. patients with corneal perforations should be shielded and immediately referred to an
                      ophthalmologist
e. Intraocular Foreign Body: will show up on an orbital X-ray because it is dense
f. Removing Foreign Bodies
         i. Anesthetize cornea with 1-2 drops of topical anesthetic such as proparacaine
                 1. drops in both eyes will reduce blink reflex
        ii. Superficial fb may be removed with a stream of irrigating solutions or forceps
      iii. a moistened sterile swab may be used to remove certain conj fb, but is not recommended for corneal
            fb
       iv. deeper fb may be removed with one of the following
                 1. hypodermic needle (22-25 gauge)
                          a. inexpensive ($6-10/100)
                          b. sterile
                          c. disposable
                 2. foreign body spud (best way to move a foreign body if it’s been there awhile)
                          a. come in a variety of shapes (golf club, chisel, etc)
                          b. cost approx $45 each
                          c. to disinfect store in zephirin chloride with anti-rust tablets added (pharmacist can
                               make this)
                          d. flaming or autoclaving may be used
        v. Procedure
                 1. place the patient’s chin on the chin rest of the slit lamp and forehead snugly against the band
                 2. give patient a fixation target to look at
                 3. focus the slit lamp on the fb
                          a. moderate mag will give better depth of field than high magnification
                          b. with some fb, indirect illumination may be better than direct
                 4. hold the patient’s lid open with 1 hand if needed
                 5. look outside of the slit lamp (not through oculars) to bring the fb remover close to cornea
                          a. bring instrument in at an angle (never point an instrument straight at the eye)
                          b. rest your hand against patient’s brow, nose, or slit lamp for better stability
                 6. look through oculars and make final fine adjustments to bring the instrument in contact with
                      fb
                 7. lift 1 edge of fb from epithelium and pry it out
                                                                                              OHP Midterm 1 Notes 17

               vi. Rust ring removal
                      1. if the fb was metallic, a residual rust ring may remain
                               a. iron is toxic to the tissue so it may inhibit healing and leave a white Coat’s ring
                      2. remove rust with a hand-spun or battery operated dental burr
                               a. Alger brush (approx $50)
                               b. Concept rust ring remover
                      3. epithelium spins off easily
                      4. Bowman’s membrane is relatively tough to penetrate; it tends to pucker up like Saran wrap

The Red Eye

  I.   Case History: most important part of the exam, should arrive at a ddx
          a. Important questions
                     i. When did it first start?
                    ii. Was it an acute onset or gradual onset?
                  iii. Have you ever had this type of red eye before?
                   iv. Which eye? (right, left, both)
                    v. Any recent eye surgeries? (cataract srgery, bleb)?-endophthalmitis
                   vi. Is it getting worse, about he same, or better?
                  vii. Any discharge? ropy vs watery vs mucopurulent
                 viii. Any symptoms? pain, gritty, fb sensation, itching, photophobia, halos
                   ix. Any recent illness? (incl friends or family members)
                    x. Any systemic conditions?
                   xi. Any allergies?
                  xii. Are you taking any topical medications?
                 xiii. Do you wear ctls?
                 xiv. Any other associated conditions with the red eye?
                  xv. Any vision changes?
 II.   Gross observation: when you are talking to the patient, you should be looking at the person’s face, body and eyes
          a. External adnexa
                     i. Eyelid
                             1. swelling/edema
                             2. ecchymosis (swelling, bruising)
                             3. eyelashes (loss, triachiasis)
                                     a. loss of lashes (madarosis) due to pulling of eyelashes, tumor
                                     b. lengthened lashes on prostaglandin
                                     c. poliosis due to staph
                             4. crusting
                                     a. bilateral blepharitis
                                     b. unilateral SCC
                             5. proptosis (eye protrusion): will see a lot of sclera on bottom
                             6. pigmentation: vitiligo (associated with EKH—learn later)
                                     a. port wine stain—Sturge Weber association
                             7. lid placement
                                     a. symblepharon Steven’s Johnson syndrome (allergic to sulfur)
                                     b. ectropion (lid sags out)
                                     c. lagophthalmos
                                     d. lid laceration
                             8. lesions
                                     a. Herpes simplex vesicles
                                                                                                OHP Midterm 1 Notes 18

                                     b. Chalazia (lesion is almost skin-colored) vs Hordeolum (red)
                                     c. Dacrocystitis (nasal bump)
                                     d. Herpes Zoster (along the midline); Hutchingson’s sign
                                     e. Lisch nodules associated with neurofibroma
                                     f. squamous cell carcinoma lesion
                                     g. molluscum contagiosum (can cause red eye)
                            9. telangiectasia
                                     a. associated with Meibomian gland issues and rosacea
          b. Lymphadenopathy
                    i. Preauricular: index and middle fingers of each hand, palpate in front of tragus of external ear
                       (forward and down)
                            1. feel for slight bony depression at the temporomandibular joint and palpate over the
                                underlying bony structures in a back and forth semicircular motion searching for the
                                depression or an elevated nodular lesion (= inflammation)
                   ii. Submandibular: fingers under jawline
                  iii. Compare the two sides, noting laterality, asymmetry, size, tenderness, or absence of
                       preauricular nodes
                            1. is it palpable?
                            2. is it visible?
                            3. is it tender to touch?
                  iv. Lymph node diseases (usually indicate a viral disease)
                            1. palpable, tender
                                     a. EKC
                                     b. Herpes simplex
                                     c. Herpes zoster
                                     d. Hyperacute conjunctivitis
                                     e. Pre-septal cellulitis
                                     f. Orbital cellulitis
                                     g. Ocular-glandular syndromes (Syphillis, Tuleremia, Cat Scratch—macular star)—
                                          visible too
                            2. palpable, non-tender
                                     a. PCF
                                     b. Inclusion Conjunctivitis
III.   Objective Testing
          a. VA
                    i. need to check distance VA in everyone (medical-legal)
                   ii. always pinhole if patient doesn’t see 20/20
                  iii. if not seeing 20/20 might need to do a quick refraction to r/o a refractive component to decrease in
                       vision
          b. Check Pupils
                    i. miotic pupils: ritis
                   ii. fixed mid dilated pupil: angle closure
                  iii. irregular pupil/fixed: posterior synechiae
                  iv. APD: orbital cellulitis, endophthalmitis
                   v. blown pupil: trauma
          c. EOMS: pain or restrictive eye movement? think Graves, orbital cellulitis, trauma (floor fracture)
          d. Lids/Lashes
                    i. blephairits
                   ii. hordeolu,
                  iii. chalazion
                                                                                    OHP Midterm 1 Notes 19

         iv. pre-septal cellulitis
          v. orbital cellilitis
         vi. meibomitis
        vii. telangiectatic vessels
       viii. ulcerations at lid margins
         ix. lid edema
          x. Zoster blisters
         xi. Herpes blisters
        xii. lice
       xiii. mites
       xiv.  Lash Epilation: temporary treatment of trichiasis
                  1. patient always look away from what you’re doing
                  2. grab base and pull firmly
                  3. usu will grow back in a few months
                  4. record number of lashes and location
e.   Conjunctiva
          i. Pattern of injection
                  1. diffuse beefy, engorged vessels that are more prominent in inferior 1/3 of conj (esp
                      in fornices): bacterial
                  2. diffuse injection: viral/scleritis/corneal ulcer/blepharoconjunctivitis/herepes simplex
                      keratitis/herpes zoster keratitis/toxic conjunctivitis
                  3. very mild diffuse injection (chemosis is greater): allergies
                  4. circumlimbal: uveitis/angle closure
                  5. sectoral: episcleritis, pingueculitis, inflamed ptygerium, phylectunolosis, fb
                  6. sub-conj heme: trauma, valsalva, blood too thin (INR), HT
                  7. corkscrew injection: carotid cavernous sinus fistula
         ii. Scleritis (more deep) vs Episcleritis
                  1. 2.5% phenylephrine: episcleritis will blanch
                  2. vessels: episcleritis will move
                  3. blue hue: scleritis will look blue
                  4. vessels criss cross: scleritis
       iii. Evaluate palpebral conjunctiva
                  1. papillae: raised small red cbumps (0.1-0.2 mm)
                            a. location of humoral immunity (Ag-ab rx) and site of release of PMN and
                                eosinophils
                            b. each papilla has central vessel running to surface (very dense compared to
                                follicle)
                            c. bacterial, allergic, toxic VKC, SLK or any other chronic irritation
                            d. least dx, often seen in normal eye due to environmental irritants
                  2. giant papillae (GPC): >1.0 mm
                  3. follicles: pale, yellow-white, elevated nondules (look more cystlike)
                            a. aggregate of lymphocytes
                            b. 0.5-1.0 mm (5X papillae)
                            c. not vascular (no central blood vessel)—may have vessels that go over cyst
                            d. most marked in lower tarsal conjunctiva (lower fornix)
                            e. viral, chlamydial or toxic
        iv. Membranes
                  1. pseudomembrane: adenoviral (VKC, Herpes etc)
                            a. stays on top of palpebral conj
                            b. may bleed, but less likely
                                                                                  OHP Midterm 1 Notes 20

                 2. true membrane: Ghonorrea, Steven’s-Johnson, Chemical/Thermal burn
                          a. becomes embedded in palpebral conjunctiva
                          b. more likely to bleed
        v. Conjunctiva Chemosis: most seen in allergic conjunctivitis but also seen in other types of
            inflammation/infection such as endophthalmitis and orbital cellulitis
                 1. can also be seen from retrobulbar mass
       vi. Discharge
                 1. copius, overflowing mucopurulent discharge: hyperacute
                 2. mucopurulent discharge: bacterial
                 3. watery: acute allergy/viral
                 4. thin, ropy transparent mucus discharge: chronic bacterial
                 5. thick, ropy mucoid discharge: VKC
                 6. frothing: Meibomian gland dysfunction
      vii. Nodules
                 1. episcleritis: movable, non-slightly tender
                 2. scleritis: nonmovable, tender
                 3. ptyergium
                 4. pinguecula
                 5. phlyctenulosis
                 6. granuloma (associated with clumps of cells)-cystoid conditions, iritis
                 7. cyst: ex: conjunctival cyst from dry eye and strab surgery (use AT)
                 8. tumor: own vascular supply, will see strawberry “frons”—pathological cancer
f. Tear Film
         i. oily tear film
        ii. TBUT <10 seconds (abnormal)
      iii. tear meniscus
g. Cornea
         i. infiltrates (rxn to something in the eye)—not an ulcer
                 1. doesn’t stain or just slightly stain in the center
                 2. ulcer will stain the whole thing but doesn’t stain, it POOLS—key thing
                          a. staining stains epithelial defects, no epithelium in ulcer
        ii. edema (will see folds)
      iii. scars
       iv. band keratopahty
        v. EBMD (mapdot, Kogans)
       vi. KPs: associated with iritis
                 1. white blood cells on endothelium of cornea
                 2. if really big, from Sarcoids or Ankylosing
      vii. Bullae (on epithelium)
     viii. Interstitital keratitis: inflammatory response to syphilis
                 1. white lines (ghost vessels) and opacification of cornea
       ix. Pannus
        x. Ulceration—stromal loss with no stroma—pool
       xi. Depression
      xii. Areas of elevation
                 1. Salzman’s—will see elevated lesions
     xiii. Staining Pattern (SPK)
                 1. diffuse: viral/toxic
                 2. inferior: bacterial/lagophthalmos/blepharitis/dry eyes
                 3. 3-9 staining: ctls, pterygium
                                                                               OHP Midterm 1 Notes 21

            4. superior: SLK
            5. fb tracks
            6. pooling: ulcer/depression
xiv.    Ulceration
            1. Central: more critical
            2. Peripheral
            3. Dendritic: associated with Herpes Simplex
            4. Corneal Ulcers
                    a. bacterial keratitis: serious, sight-threatening corneal infection
                             i. 3 most common types: staph, strep and pseudomonas
                                      1. signs
                                               a. infiltrate in the corneal stroma with associated stromal
                                                    loss and an overlying epithelial defect
                                               b. anterior chamber reaction
                                               c. hypopyon
                                               d. mucopurulent discharge
                                               e. stromal edema
                                               f. conjunctival injection
                                               g. eyelid edema
                    b. fungal ulcer: should be considered when there is trauma secondary to vegetative
                        matter or in a immunocompromsied patient
                             i. signs
                                      1. white-grayish infiltrate with feathery borders and associated
                                           stromal loss with epithelial defect
                                      2. usually also satellite infiltrates
                                      3. anterior chamber reaction
                                      4. hypopyon
                                      5. conjunctival injection
                                      6. stromal edema
                                      7. eyelid edema
 xv.    Abrasion: need to check for fb under upper lid
xvi.    Types of Stain (use 2 separate strips to min chance of cross infection)
            1. NaFl: stains epithelial defects
            2. Rose Bengal: stains mucus, dead and damaged tissue
                    a. for herpes, virus
                    b. may present as SPK that’s not getting any better
            3. Lissamine Green: similar to RB but doesn’t sting as much
            4. if you suspect bacterial etiology, take a culture before instilling any dx or tx agent
xvii.   Corneal Sensitivity: diagnostic in Herpes Simplex Keratitis (specifically chronic HSK)
            1. qualitative (cotton wisp)
                    a. touch central cornea with cotton (avoid menace reflex by coming from the side)
                    b. if patient blinks, tears, or acknowledges sensation, have them grade it and
                        compared to other eye
                    c. test unaffected eye first
                    d. testing ophthalmic of the trigeminal
                    e. will only see decreased sensitivity if chronic herpes simplex, not acute
            2. quantitative (Cochet and Bonnet’s aesthesiometer)
                    a. is available to quantify corneal sensation
                    b. uses ballpoint pen-like device with a nylon thread protruding from its front
                    c. thread changes in length to measure min perceptible sensation
                                                                                               OHP Midterm 1 Notes 22

                                  d.   shorter the thread, the less the corneal sensation (puts greater pressure on cornea)
                                  e.   sensitivity recorded as length of filament
                                  f.   measured in grams/mm squared
                                  g.   average = 11.8
         h. Anterior Chamber
                   i. Cells
                  ii. Flare
                 iii. Hypopyon
                 iv. Hyphema-blood resting in AC—can lead to blood stained cornea
                  v. Micro-hyphema (smaller)-don’t have blood resting in AC< will have blood floating in AC (kind
                      of look like cells)
         i. Angle Estimation
                   i. r/o angle closure
                           1. will see all sclera
                           2. or anterior synechiae
                  ii. do gonio after checking IOPs
         j. IOPs
                   i. Applanation tonometry
                  ii. needs to be done unless contraindicated (compromised cornea or conjunctiva)
                 iii. can do NCT if significant corneal involvement
                 iv. helps with ddx with iritis, angle closure glaucoma
         k. Iris
                   i. uveitis: check for nodules on the iris, posterior synechiae
                  ii. dialysis (tear in iris): trauma
                 iii. neovascular glaucoma: neovascularization
                 iv. iritis: nodules around the iris
         l. Vitreous
                   i. vitritis: can’t see anything, appears completely white
         m. Fundus
                   i. DO (at least do undilated fundus on every initial visit)
                  ii. DFE (patients with uveitis)
                 iii. Hx of trauma (need to r/o posterior or int uveitis and any retinal involvement from trauma)
                           1. may see choroidal rupture (concentric ring that is around nerve head)
                 iv. patient with herpes simplex/zoster—can cause retinal necrosis
IV.   Other
         a. Chemical Burn: damage depends on speed of tx and thoroughness of tx (key thing = the redder the better,
            if it’s white, it means it’s ischemic)
                   i. alkali: rapid penetration (lye, lime, NaOH, ammonia)
                  ii. acid: rarely leads to penetration; localized to areas of contact (sulfuric acid)
                 iii. S/S (Variable)
                           1. pain
                           2. injection, chemosis
                           3. keratitis, corneal clouding
                           4. neo
                           5. scarring
                           6. symblepharon formation
                           7. tissue necrosis (limbal burns have poor prognosis due to vascular damage and resultant
                                necrosis)
                                    a. eye may appear “white and quiet”
                                    b. absence of blood vessels through conj vessels
                                                                                        OHP Midterm 1 Notes 23

                  8. secondary uveitis, infection, glc
                  9. loss of vision
        iv. Management
                  1. patient calls office…
                            a. you (or staff) find out what was splashed in eye and patient’ phone number
                            b. instruct patient to immediately irrigate the eye and continue until you call back
                                      i. irrigate for at least 10-15 minutes
                            c. if you are not familiar with the substance, call poison control center and ask what
                                was in product, acid, base, ocular manifestations
                            d. call patient back to advise how long to continue irrigating before he/she starts for
                                your office
                  2. patient reaches your office…
                            a. instill anesthetic (proparacaine)
                            b. retract lids and irrigate eye
                                      i. squeeze bottle of saline is OK for mild injuries
                                     ii. IV saline infusion set is better for more serious injuries in which 1000-
                                         2000 mL of irrigation is needed
                                   iii. usually need to irrigate for at least 30 min
                                    iv. Morgan Lens (ctls in your eye) and connected to the IV bag
                                     v. be sure to evert lids, irrigate cul-de-sacs and remove any particles
                                    vi. continue eto irrigate until pH in fornix is 7.2-7.4 (pH papers are
                                         available in pharmacies)
                            c. take visual acuities
                            d. do biomicroscopy to assess damage
                            e. apply topical antibiotic such as bacitracin, erythromycin, polysporin
                            f. CAP
                                      i. apply cycloplegic such as 5% homatropine
                            g. may need to use steroids
                            h. use PF AT’s every hour
                  3. moderate to severe cases may require hospitalization and steroids
                  4. follow daily
                  5. monitor IOP
  b. RPS Adeno Detector: collect, transfer, buffer, read
          i. can tell if they have a viral conjunctivitis
         ii. second line shows up = positive
V.   Culturing: obtain specimen and place it in a different nutrient media so organism can grow to ID
     organism and perform sensitivity testing
         a. Indications
                   i. neonatal conjunctivitis
                  ii. hyperacute conjunctivitis
                iii. corneal ulcer
                 iv. post-operative infection
                  v. severe chronic conjunctivitis
                 vi. orbital cellulitis
                vii. periorbital abscess
               viii. r/o virulent bacteria, virus, fungus or parasite infection
                 ix. obtain specimen using culturing kit
                  x. can be collected by OD and should not be interpreted by OD
         b. Appropriate to culture
                   i. >2 mm lesion within 2 mm of visual axis
                                                                             OHP Midterm 1 Notes 24

         ii. >2 peripheral ulcerative lesions
c. Essential to culture (know these)
          i. immunocompromised patient
         ii. hospitalized or nursing home patient
       iii. health-care worker
        iv. progressive lesions
         v. pediatric infections
        vi. hyper-purulent lesions
       vii. h/o organic trauma
      viii. central K ulcer
        ix. post-operative infections
         x. ulcers that are not improving with current tx
d. how to culture
          i. sample
                  1. 1st = lids
                  2. 2nd = conjunctiva (topical anesthetic optional)
                  3. 3rd = cornea (topical anesthetic mandatory)
         ii. materials needed
                  1. transport swabs with agar
                  2. culturing media (if doing in office)
                  3. kimura spatula (if doing scrapings)
                  4. alcohol lamp
                  5. sterile non-preserved saline
                  6. topical anesthetic
e. if using a cotton swab…
          i. lids and conjunctival samples only!
         ii. do without anesthetic
       iii. pre-moisten (with sterile saline) swabs
        iv. roll over each lid edge and conj esp lower fornix
         v. sample both eyes even if only 1 eye infected
                  1. determine indigenous microflora
                  2. watch for cross contamination
f. if using Kimura Spatula
          i. make sure Kimura spatula is sterile
         ii. spatula can be sterilized over flame of an alcohol lamp (be sure to wait for temperature to
             go back down to normal)
       iii. anesthetize the cornea
        iv. scrape base and leading edge ulcer firmly using short firm strokes in 1 direction
         v. transfer scrapings onto transport swab which will then be sent to lab for culturing
g. Sensitivity Testing
          i. single isolated colony is placed in broth to grow
         ii. streaked onto agar plate
       iii. several disks of ab of known concentration are placed in agar
        iv. if bacteria sensitive to ab, it won’t grow around ab disc
         v. area around disk determines how sensitive or resistant the bacteria are to a certain ab
h. Media
          i. blood agar: aerobic bacteria (most pathogens)
         ii. chocolate agar: Neisseria, Haemophilus, Moraxella
       iii. saboraud: fungi
        iv. Thayer-Martin: Neisseria
                                                                              OHP Midterm 1 Notes 25

          v. Thioglycolate broth: aerobic and anaerobic bacteria
         vi. Lowsnstein-Jensen: mycobacteria
        vii. Non-nutrient agar with E.Coli overlay: acanthamoeba
i.   Gram: staining procedure done to determine what type of organism present
           i. Classification
                  1. Shape: rods, cocci
                  2. Color
                           a. pink = gram (-)
                           b. purple = gram +
                  3. does not grow organisms
          ii. Procedure
                  1. heat fix the slide over flame
                  2. cover slide with crystal violet stain for 1 min
                  3. rinse gently with tap water
                  4. cover slide with gram iodine for 30-60 sec
                  5. rinse gently with tap water
                  6. cover slide with Safranin counter stain for 1 min
                  7. rinse gently with tap water
                  8. air dry
j.   Cytology: provide info regarding morphology of microorganism, inflammatory cellular response,
     and epithelial cell composition
           i. looking at cells utilizing smears and scrapings
          ii. performed after obtaining cultures (using anesthetic)
        iii. Stains
                  1. DiffQuick Stain (fast and easy)
                           a. dip 5X for 1 sec into fixation solution
                           b. dip 5X for 1 sec into red stain
                           c. dip 5X for 1 sec into blue stain
                           d. rinse with distilled water and let air dry (vertically = key)
                  2. Giemsa Stain: not practical to perform in office because it requires a buffer to
                       be mixed up right before staining
                  3. PAP Stain: look for inclusion bodies caused by Chlamydia
         iv. Cells to look for on cytology slides
                  1. epithelial cells (normal)
                           a. normal cells of cornea and conj
                           b. larger than any white blood cell
                           c. nucleus stains dark and cytoplasm stains purple
                           d. irregularly shaped
                  2. leukocytes (WBC)s
                           a. granulocytes (PMNs)
                                       i. neutrophils: granular cytoplasm
                                              1. multilobed dense nucleus that stains violet or purple
                                              2. cytoplasm stains pink
                                              3. found mainly in acute and chronic bacterial, fungal and
                                                  any hyperacute conjunctivitis
                                      ii. basophils: bilobed dense violet staining nucleus
                                              1. cytoplasm granules stain blue making it difficult to see
                                                  nucleus
                                              2. rarely seen in conj smears and are indicative of an
                                                  allergic rxn
                                                                                              OHP Midterm 1 Notes 26

                                                     iii. eosinophils: bilobed dense purple staining nucleus
                                                              1. cytoplasm granules stain red and can obscure nucleus
                                                              2. one eosinophil seen on a slide is indicate of allergic
                                                                  reaction
                                             b. agranulocytes (mononuclear)
                                                       i. lymphocytes
                                                              1. smaller than PMNs
                                                              2. single large dense nucleus that stains dark purple
                                                              3. slight amt of agranular light blue staining cytoplasm
                                                              4. major cell in directing immune response
                                                              5. found in viral infections and toxic follicular
                                                                  conjunctiva
                                                      ii. monocytes
                                                              1. larger than PMNs
                                                              2. single crescent shaped nucleus (horseshoe shaped)
                                                              3. agranular cytoplasm
                                                              4. frequently seen with lymphocytes in viral infections
                                                              5. precursor to macrophages
                                   3. Cells Summary—know these
                                             a. normal eye: epithelial
                                             b. viral: lymphocytes, monocytes
                                             c. chlamydial: lymphocytes +neutrophils in equal quantity
                                             d. acute bacterial conjunctivitis: neutrophils predominant, few lymphs
                                                 and monos
                                             e. chronic bacterial: less neutrophils, lymphs and monos than acute
                                             f. allergic: eosinophils predominant, few basophils
          k. Thermanox Disc: study cellular response in various conj disorders
                   i. conjunctival cells adhere to these disc w/o anesthetic
                  ii. disc with cells are stained with modified Wright’s stain (Diff-Quick)
VI.   Prescription
          a. We can prescribe: drops, ointment, pills (need to put # of pills) and suspensions
          b. amount of days is not as crucial because it may change throughout course of tx
          c. Example in handout

								
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