EyeWorld Asia-Pacific December 2015 Issue

53 EWAP CORNEA December 2015 by Ellen Stodola EyeWorld Staff Writer DALK and crosslinking for a number of conditions Experts presented at World Cornea Congress VII on a variety of techniques for treating keratoconus, ec- tasia, and other diseases D uring the World Cornea Congress VII session focusing on keratoconus, ectasias, ALK, and other lamellar grafts, experts highlighted their preferred techniques and treatments. They also discussed in which cases certain procedures would be most appropriate. The keynote talk focused on treatment paradigms in keratoconus, detailing specifics about the prevalence of the disease, ways to diagnose and screen patients, and best approaches for treatment. Other presenters in the session followed up on their presentations on using deep anterior lamellar keratoplasty (DALK) and crosslinking for corneal ectasia. DALK management and com- plications David Rootman, MD , adjunct professor, Ben-Gurion University of the Negev, Beersheba, Israel, professor, University of Toronto, and medical director of the TLC Yonge Eglinton Laser Eye Centre, Toronto, discussed DALK and how to approach complications. His preferred technique in DALK is a modified Anwar technique, and Dr. Rootman chooses to use a Fogla dissector and Fogla cannula. There are some potential complications that can occur with DALK. “The first thing that you After removal of the anterior stroma in DALK, clear Descemet’s membrane re- mains on top of an air bubble in the anterior chamber. Source: David Rootman, MD might encounter is that you might not be successful in generating the big bubble.” If this occurs, Dr. Rootman will usually try a second or even a third time to generate the big bubble. Another potential complication involving the big bubble in DALK is that the surgeon may end up with a type 2 bubble instead of type 1. Surgeons have to recognize this and be more cautious when dissecting, Dr. Rootman said, because the type 2 bubble is not as strong—it’s just Descemet’s membrane without anterior or posterior stroma. When addressing the unsuccessful bubbles, the technique Dr. Rootman prefers is to hydrate the stroma with balanced salt solution. He recommended not using OVD because this will make the stroma tough and difficult to dissect. “Once I’ve hydrated the anterior stroma, I’ll peel it off layer by layer until I get down to Descemet’s membrane and then proceed as I usually do,” he said. The surgeon may potentially encounter a tear or perforation in Descemet’s membrane. For a perforation, Dr. Rootman said his old rule of thumb was that if he could inject air into the anterior chamber and if the sclera was held by Descemet’s membrane, he could proceed with DALK. He is even more confident now in the technique and would possibly still proceed even with a larger tear. “I think it’s important to emphasize that you shouldn’t just give up if you don’t get the big bubble the first time,” Dr. Rootman said. Even if you do a dissection and leave a little stroma, patients are likely to do well, he said. Learning the skills and technique for DALK is important because of the possibility to help keratoconus patients avoid a rejection episode or endothelial failure. You can treat a higher percentage of these patients with DALK rather than a penetrating graft, he said. Needle and cannula DALK Luigi Fontana, MD , Reggio Emilia, Italy, spoke on needle and cannula DALK. “DALK is more commonly performed in keratoconus patients when both glasses and contact lenses do not provide adequate correction,” he said. “In these cases the DALK technique of choice is the big bubble technique as it may allow [surgeons] to bare the Descemet’s membrane over a large surface area, providing a pristine graft– host interface and allowing for visual results comparable to PK.” Dr. Fontana said it is easier now for surgeons to learn DALK because of the numerous meetings that offer courses, wet labs, and video resources. “I would recommend practicing DALK continued on page 54