EyeWorld India September 2020 Issue

EWAP SEPTEMBER 2020 9 FEATURE EK, you’re removing the back layer, so anything left on the front can still affect vision. Assuming the patient has significant ocular surface irregularities, Dr. Rapuano said there are a couple of ways to handle this. “You can treat it prior to the EK, in the office or with an excimer laser PTK, to try to get the cornea as smooth as possible and then do EK,” he said. This would be especially important if doing combined EK and cataract surgery because the cornea needs to be as smooth and regular as possible for optimal calculations for cataract surgery. If the patient already had cataract surgery and there are lumps and bumps, you can treat beforehand or go in for EK. Doing a superficial keratectomy at the time of EK and scraping off irregularities often works well, he said. “When I see a lot of subepithelial fibrosis, basement membrane dystrophy, corneal haze, it doesn’t bother me because I can do a superficial keratectomy intraoperatively,” Dr. Dhaliwal said, adding that she tries to separate cataract surgery and corneal transplants if she can rather than combining the procedures. Generally, she will address whichever condition is more serious first. “If they need both, I like to separate and stage the two procedures,” she said, adding that the keratometry can be significantly off in these patients when you’re doing combined surgery. If they have a lot of scarring, haze, and bullae, Dr. Dhaliwal will use the Ks from the other eye if doing the cataract surgery first. When doing a transplant first, she will get new Ks after the cornea becomes clear and compact and the surface becomes smooth. Dr. Dhaliwal uses a bandage contact lens in these patients postoperatively. If the patient is neurotrophic, amniotic membrane may help, and she also likes to use collagen shields soaked in an antibiotic. W. Barry Lee, MD, said he addresses Salzmann’s nodules at the same time as the EK. “I perform a lamellar keratectomy with a Tooke corneal knife, place topical mitomycin-C 0.02% onto the central cornea with a sponge for 30–60 seconds, rinse with two bottles of balanced salt solution, then start my EK,” he said. “I put these patients in a therapeutic bandage lens after I have managed the air bubble, which typically occurs during a check 1 hour after surgery.” For subepithelial scarring, he always evaluates the depth of the scarring at the slit lamp. If it is truly subepithelial, he uses superficial keratectomy at the time of EK. If the scar extends into the stroma, he uses anterior segment OCT to help determine whether PTK would be beneficial or whether a full thickness transplant should be considered. OSD, dry eye, blepharitis, and glaucoma drop toxicity Dry eyes and blepharitis often occur concurrently in these patients, so both diseases must be checked and adequately treated prior to EK, Dr. Lee said. “If tear deficiency is present, I start with preservative-free tears, topical cyclosporine, or lifitegrast,” he said. “Punctal plugs may be used as well, but I avoid these if concurrent blepharitis is present.” Dr. Lee prefers to start drops first and use plugs secondarily in cases without blepharitis, allowing inflammatory cells on the ocular surface to get better clearance via the puncta before surgery. If glaucoma drop toxicity is present, he tries to get drops switched to preservative-free solutions prior to EK. Dr. Dhaliwal stressed the importance of optimizing the surface. Often during EK, as you’re getting the graft to Fluorescein staining demonstrating severe superficial punctate keratopathy. Moderately elevated Salzmann’s nodular degeneration; the brown line indicates chronicity. Source (all): Christopher Rapuano, MD