Eyeworld

60 | EYEWORLD | DECEMBER 2023 C ORNEA LESSONS LEARNED About the physicians Francis Mah, MD Scripps Clinic La Jolla, California Lisa Nijm, MD, JD Warrenville Eyecare & LASIK Warrenville, Illinois by Ellen Stodola Editorial Co-Director A ccording to Lisa Nijm, MD, JD, neu- rotrophic keratitis (NK) is still con- sidered a rare disease, but she thinks that it occurs more often than many realize. "It's difficult to isolate the exact prevalence because so many times there is a delay in diagnosis. We might not even realize in the early stages that the patient has NK, and that's what's contributing to their poor healing." While NK isn't something that you necessar- ily see daily in a busy tertiary care cornea prac- tice, Francis Mah, MD, said he sees it a couple times a week. It can be a patient with trauma or an abrasion, or a patient who just had surgery and is taking a couple of extra days to heal. "[There is] this category we call persistent corneal epithelial defects, and in somewhere between 30–60% of them, the reason they're not healing is NK," Dr. Mah said. "It's important to decide why the patient is not healing because it's not normal for a patient to walk around with a persistent corneal epithelial defect." He added that it's important to ask the patient about their history to figure out what might have predisposed them to this. Herpes simplex and herpes zoster are the most common reasons for NK, Dr. Mah said, but it also could be a history of trauma, a recent infection, or a chemical injury. "Getting the history and start- ing the thought process for why this person's cornea isn't healing is the first step." Once you have the history and find, for example, the patient has diabetes, a history of herpes or shingles, they had LASIK, or they have been on eye drops for a long period of time, you might start wondering about NK. You would then want to do corneal sensitivity testing, Dr. Mah said, either qualitative or quantitative. Testing could involve taking a cotton swab and pulling out the cotton part a bit and testing the patient's sensation. "Corneas are exquisite- ly sensitive, so if the patient responds, that's normal," he said. "If they don't respond or it's delayed, that's a little abnormal." Dr. Nijm also pays particular attention to a patient's history in considering NK. Long-term contact lens wear is something specifically to look for because many patients begin contact lens wear in their teens and are coming in 50 or 60 years later; that's a long time to be wearing contact lenses, and the effects on the cornea and the cornea nerves can manifest as NK, she said. She added that factors like diabetes, MS, and acoustic neuroma or meningiomas may also play a role and reduce corneal sensitivity. Addressing neurotrophic keratitis continued on page 62 Persistent corneal epithelial defect; grayish-white edge, heaped up epithelium edge, frequently central Source: Francis Mah, MD

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