Eyeworld

EW FEATURE 70 induced and how much is pre-exist- ing? You just don't know." One potential downside to planned simultaneous surgery is the limited reimbursement; Medicare will only pay for half of an addi- tional surgery if done in conjunc- tion with cataract extraction. EW Editors' note: Drs. Nasser and Palmon have no financial interests related to their comments. Dr. Tseng holds a patent on amniotic membrane and has research supported by the National Institutes of Health (Bethesda, Md.). Contact information Nasser: 707-486-4804 Palmon: 239-768-0006 Tseng: 305-274-1299 February 2011 Challenging cataract cases September 2011 International point of view Saudi Arabia M y preferred plan with pterygium and cataract surgery is a combined approach. I tend to perform cataract surgery, intraocular lens im- plantation, and pterygium resection in the same operation. However, if the pterygium is large enough to reach the visual axis, I prefer to per- form the pterygium resection first and then perform the cataract approach in a second surgery. Large pterygia tend to induce significant astig- matism causing unpredictable refractive results if done simulta- neously with the cataract surgery. In these cases, I wait until the topography stabilizes (an average of three separate measure- ments) to perform the keratometry and IOL calculation. If the pterygium is small and not causing astigmatism (<0.5 D), I prefer to perform the IOL calculation and the cataract sur- gery with IOL implantation as follows: 1. Perform phacoemulsification surgery through a small in- cision (2.2 mm) at 135 degrees (superior approach) with a para- centesis at 70 degrees. If the pterygium obstructs paracentesis/ clear cornea creation, 120 or 80 degrees is the preferable site of incision. 2. I use a two-step biplanar clear corneal incision approach, with a rectangular tunnel shape. That configuration warrants the best water-tightness compared to other approaches. 3. After phacoemulsification is completed, I perform IOL insertion in the capsular bag and do not remove viscoelastic material. I tend to hydroseal the clear cornea and paracentesis wounds and pressurize the eye slightly, in order to achieve a firm eye. This facilitates the removal of tissue with the approach I use. Then I start "peeling" off the fibrovascular conjunctival tissue from the base of the pterygium toward the apex. This technique of removal makes the fibrotic tissue become detached from the surface of the cornea in a lamellar fashion and leaves the corneal stroma mostly intact. By doing this, you will note that the epithelial cell layer comes off in a somewhat larger fashion than the fibrovascular tissue itself, but that warrants a smoother healing of the epithelium. I do not use blades to re- move the pterygium because I believe they remove unpredicted amounts of corneal stroma, creating potential for dellen forma- tion. 4. After the pterygium is resected, I remove the viscoelastic material from the anterior chamber and hydroseal again the clear corneal incision/paracentesis to promote water-tightness. 5. If the patient is over 60 and this is his/her first pterygium removal, I tend to perform bare sclera. For younger patients or recurrent pterygia, I prefer autologous graft including limbal stem cell transplant. I do not use MMC or amniotic membrane for pterygia in the cataract patient age group. Because recurrence rates are much lower in this group, either with bare sclera or autologous graft, they tend to do well. Pterygia continued from page 69 Ashley Behrens, M.D.

• Cover