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TIPS AND TECHNIQUE FOR SUCCESS WITH CC4204BF COLLAMER SINGLE

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TIPS AND TECHNIQUE FOR SUCCESS WITH CC4204BF COLLAMER SINGLE
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9/5/2009
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TIPS AND TECHNIQUE FOR SUCCESS WITH CC4204BF COLLAMER® SINGLE

PIECE LENS.





Elizabeth A. Davis, MD, FACS



The CC4204BF lens from STAAR Surgical is a single piece plate haptic designed lens made from

Collamer material. Despite concerns with earlier generations of plate haptic lenses, the Collamer plate

lens has a unique design that has overcome such issues. Older plate haptic lenses were too long for

most capsular bags and this resulted in a buckling of the IOL. In contrast, the Collamer single piece lens

has been downsized to 10.8 mm. This smaller size, in combination with the highly flexible Collamer

material, allows the implant to gently unfold into the eye and to be manipulated to seat precisely into the

capsular bag with a precise fit. Furthermore, this fit allows for excellent centration without lens tilt, which

can occur with open looped single piece lenses which do not conform to the capsular bag. Even with one

haptic in the bag and the other in the sulcus, this lens remains centered. Bag fixation was a problem with

previous generation lenses and as such, older lenses had the potential to eject into the vitreous cavity

during a YAG capsulotomy. The Collamer plate IOL has large positioning holes through which fibrosis of

the anterior to posterior capsular leaflet occurs. This fibrosis as well as the adherence of the hydrophilic

Collamer material to the capsule fixates the lens into position in the bag, preventing displacement during

YAG capsulotomy.









Old Silicone IOL New Collamer Single Piece

(small holes, long length) (capsular fit, and large holes)



This lens is highly biocompatible as a result of two chemical properties. The first is due to the inherent

negative charge of the Collamer material. Since proteins and cells that circulate in the aqueous fluid are

also negatively charged, there is a charge-charge repulsion and inhibition of deposition on the lens

surface. Secondly, the collagen composition of the lens attracts fibronectin. A monolayer of fibronectin

has been shown to deposit on the lens surface. This coating makes the lens immunologically “invisible,”

hence enhancing its biocompatibility.









Cross-section of capsular bag with Collamer Single Piece

IOL. This is identical to the fixation of all three piece IOL

designs in the bag

A study by Elizabeth A. Davis, MD, FACS compared postoperative cell and flare as well as other

measurements of biocompatibility in eyes undergoing clear cornea phacoemulsification randomized to

receive either an acrylic IOL, a silicone IOL, or a Collamer plate IOL. There was a trend for lower

postoperative inflammation with a Collamer IOL. Although this was not statistically significant, as a result

of small sample sizes, this study demonstrated that Collamer is at least as biocompatible as second

generation silicone and acrylic, even in eyes at higher risk for postoperative inflammation (glaucoma,

pseudoexfoliation, diabetes).



One of the more exciting technologies in refractive surgery is the advent of custom treatments.

Diagnostic testing of optical aberrations with infrared abberometry can now be performed to examine

functional vision in patients. Customized laser treatments are now a reality in LASIK surgery. These

treatments help to improve quality of vision outcomes. Cataract surgery is now becoming refractive and

surgeons are looking to achieve similar results to corneal based customized treatments. In a recent study

conducted by Robert G. Martin, MD, and Donald Sanders, MD, PhD higher order abberations following

cataract surgery were measured. Collamer IOLs had significantly lower higher order abberations as

compared to STAAR silicone plate haptic IOLs and Alcon SA-60 IOLs. This suggests that Collamer

lenses provide better quality vision following cataract surgery.





1.4 1.28 1.13

1.2 0.93

1

RMS Value









0.8 0.6

0.6

0.4

0.2

0

STAAR STAAR Alcon AMO

Collamer Single SA60 Sensar

Piece







Gale Martin MD High Order Abberation Study Results



Indeed the Collamer material is the material used in the Visian ICL, the phakic IOL used to correct

refractive errors intraocularly. The FDA trial of this lens demonstrated excellent visual outcomes and

patient satisfaction.



TIPS AND TECHNIQUES FOR SUCCESS



Successful outcomes are achieved with the collamer single piece IOL when certain measures are taken

during the procedure.









Mark the cornea with a 6.0mm OZ marker to help provide The implanted Collamer lens optic of 6.0mm

a guide for making the capsulorhexis. 6.0mm on the cornea is just inside of the capsulorhexis.

equates to about 5.0mm on the capsule. Tear capsulorhexis

outside of this tracemark and produce a 6 to 6.5mm capsulorhexis.









E. A. Davis, MD, FACS -Tips and Technique for Success with CC4204BF COLLAMER Single Piece Lens. -2-

Firstly, it is important to make a large capsulorhexis with this lens. Preferably, the size should be 6 to 7

mm in diameter. The large capsulorhexis has been found to be associated with a lower rate of posterior

capsular opacification.









This cross-section of the lens capsule

shows the giant epithelial A cells

on the Anterior capsule area



Additionally, this reduces the risk of capsular phimosis. Capsular phimosis causes the capsule to fibrose

and contract around the lens. Because of the highly flexible nature of the lens, this can result in a bowing

anterior or posterior of the lens optic and a resulting refractive shift.









Anterior capsular contraction from Picture depicts four relaxing anterior capsulotomies made

ACO A cell migration with the YAG laser to release capsular phimosis in an eye

with a small capsulorrhexis





This has resulted in some reports of late hyperopic shifts. Similar refractive shifts can occur with other

lenses (in particular the Crystalens) when late contraction of a small rhexis occurs. In the event that this

happens, it is suggested that the surgeon widely dilate the pupil and perform several relaxing YAG laser

anterior capsulotomies in all four quadrants. This releases tension on the lens and allows it to resume its

initial position in the capsular bag (see Figure 1). However, with a large 6 to 7 mm capsulorhexis, we

have seen no hyperopic or myopic shifts with the Collamer lens. Our results with the techniques

described herein have resulted in excellent refractive stability and visual outcomes.



The CC4204BF Collamer single piece IOL is inserted into the eye with the MICROSTAAR Indigo delivery

system. This is a plunger system that should be carefully and correctly loaded. It is critical that the foam-

tipped plunger never overrides the lens. Additionally, a pumping technique must be employed allowing

the plunger to withdraw periodically. This maintains viscoelastic in front of the plunger tip, which helps

push the lens forward. In the optimal situation, the plunger tip never actually contacts the trailing haptic of

the lens. Finally, the lens does not need to fully eject into the anterior chamber before withdrawing the

injector. Once the optic and two-thirds of the trailing haptic have emerged from the injector, the injector

can slowly be withdrawn from the incision. The trailing haptic can be easily dunked beneath the

capsulorhexis with a second instrument placed through the paracentesis. This technique, when done

correctly, will prevent truncating the trailing haptic between the plunger and injector tip.









E. A. Davis, MD, FACS -Tips and Technique for Success with CC4204BF COLLAMER Single Piece Lens. -3-

The new MICROSTAAR Indigo delivery system is similar to the PF injector and foam-tipped plunger, but

STAAR has improved the design such that they are matched to produce a more consistent fit with every

lens insertion. The new Indigo system has an oval shaped plunger rod that is much more rigid and fits

only when in proper alignment for moving the Collamer implant down the SFC25 funnel cartridge. This

new design eliminates the risk of the plunger overriding the lens. Nevertheless, the surgeon should still

continue with the technique of pumping the implant forward during injection. With the Indigo system,

however, the surgeon can perform the delivery more rapidly without risk of jamming the plunger in the

cartridge. This is a significant improvement in the delivery system for this lens and makes the loading of

the lens less susceptible to technician error. (photos of Indigo delivery shown below)









At this point, the surgeon should “bump”

Slow and steady injection with Indigo the lens with a pumping of the plunger injector

system behind the Collamer IOL system to prevent over-ride on trailing haptic









Note that final delivery of the trailing haptic Once inside the eye, the trailing haptic

is done with a hydraulic action between the is “dunked” into the capsularhexis with a

Indigo foam tip plunger and viscoelastic side port instrument and rotated to the

behind the implant horizontal axis



Once the lens is positioned in the capsular bag, it is recommended that the lens be rotated to a horizontal

orientation. When the capsular bag is put on stretch by the presence of an IOL, capsular striae may be

induced. Rarely, visual aberrations may result when light is refracted by the striae due to a Maddox rod

effect. These aberrations are much better tolerated when they are horizontal rather than vertical in

nature.



A few studies presented at the ASCRS meeting in 2004 showed a pseudo-accommodative effect with the

Collamer plate IOL. That is, pseudophakic patients who receive this implant had excellent unaided near

vision as well as distance vision postoperatively. Because the Collamer material is very flexible in nature,

this result is not surprising. Whether accommodation results in an anterior shift of the IOL is not known,

but possible. Greatest effects were seen in patients with high powered implants (greater than 24.0 D).

Postoperative cycloplegia was maintained for one week to aid in positioning of the lens posteriorly.

Additional research and studies of this effect will provide us with better insight, but certainly this

phenomenon can be demonstrated by individual surgeons in their own patients.



In conclusion, the Collamer Single Piece IOL is a highly biocompatible lens of high optical quality.

Because of this, it can be used even in eyes at high risk for postoperative inflammation. Careful attention

to surgical technique specific to this lens ensures good outcomes. In some instances, it may be possible

to achieve pseudoaccommodation with this single piece IOL with excellent uncorrected distance and near

vision.





E. A. Davis, MD, FACS -Tips and Technique for Success with CC4204BF COLLAMER Single Piece Lens. -4-


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