EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/1516463
86 | EYEWORLD | SPRING 2024 C ORNEA by Ellen Stodola Editorial Co-Director About the physicians Sophie Deng, MD, PhD Professor Walton Li Endowed Chair in Cornea and Uveitis Co-Chief, Cornea Division Stein Eye Institute University of California, Los Angeles Los Angeles, California Marjan Farid, MD Director of Cornea, Cataract, and Refractive Surgery Gavin Herbert Eye Institute University of California, Irvine Irvine, California Bennie H. Jeng, MD Harold G. Scheie Chair and Professor Chair, Department of Ophthalmology Director, Scheie Eye Institute University of Pennsylvania Perelman School of Medicine Philadelphia, Pennsylvania I dentifying and treating patients with limbal stem cell dysfunction or deficiency can be a challenging process. Several physicians discussed how they handle these patients, including which techniques are available for mild to more severe disease. Bennie H. Jeng, MD The first thing to know is the difference be- tween deficiency and dysfunction, Dr. Jeng said, because limbal stem cell deficiency means there are no more cells left, or at least not in certain areas. Dysfunction could mean that there are cells, but they just aren't working, he said. "I make that distinction because there are cases, for example, in contact lens-associated limbal stem cell dysfunction, if you give patients a contact lens holiday, they could recover, or other cells nearby could recover or repopulate." While Dr. Jeng said it's hard to give an actu- al incidence or prevalence, the concept of limbal stem cell dysfunction or deficiency is underdi- agnosed in general because if you don't look for it, you won't find it. If you look carefully, 5–10% of people with chronic contact lens wear have some mild degree of limbal stem cell deficiency or dysfunction, he said. Dr. Jeng said that contact lens intolerance and taking a contact lens holiday is the first rung of treatment for this condition. Severity escalates when the stem cells are wiped out from disease or inflammation. It becomes a problem, Dr. Jeng said, when there is more than 4–6 contiguous clock hours of deficiency because then the surface can't re-epithelialize correctly. The cells that then populate the sur- face are conjunctivalized epithelial cells rather than clear corneal cells, he said. Many of these things—like chemical burns, Stevens-Johnson syndrome, and autoimmune disorders—that lead to LSCD are already being managed by corneal specialists. Dr. Jeng said treatment of every individual patient is different. It depends on the degree and how active the disease is. "I actually had a patient who had 11 clock hours of stem cell deficiency from a chemical insult in the past," he said. "That 1 clock hour allowed him to re-epithelialize in the very center of his cornea, and I had him in a scleral lens to protect the Treatment of limbal stem cell deficiency Aniridic keratopathy and total limbal stem cell deficiency—preopera- tive photo of the left eye Aniridic keratopathy and total limbal stem cell deficiency—left eye 14 years postop after keratolimbal allograft Source (all): Edward Holland, MD Aniridic keratopathy and total limbal stem cell deficiency—preopera- tive photo of the right eye Aniridic keratopathy and total limbal stem cell deficiency—right eye 15 year postop after a keratolimbal allograft