Corneal Neuropathic Pain

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Identifier Corneal_Neuropathic_Pain_1080p
Title Corneal Neuropathic Pain
Creator Andrew G. Lee, MD; Daniel Rodricks
Affiliation (AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (DR) Class of 2023, Baylor College of Medicine, Houston, Texas
Subject Cornea; Neuropathy; Confocal; Small Fiber
Description Dr. Lee lectures medical students on the subject of corneal neuropathic pain.
Transcript I want to talk to you about how corneal neuropathic pain can come to neuro-ophthalmology and just like neuropathic pain in other parts of the body like small fiber neuropathies, the patients complain about pain that's disproportionate to what we see on the exam. In fact normally the exam is normal. So the most common neuropathic pain that we see is like dry eye, and so those dry eye patients are easy to diagnose because we have something we can see on the slit lamp examination, and those patients sometimes have had refractive procedures like LASIK. And as you know the cornea is the most innervated organ in our body. It has more nerves per square inch than the other parts of your body. So it's super sensitive because it's got all this nerve input. And so as you know when you're making a LASIK flap, you have to cut those nerves and then the nerves regrow. So after the regrowth of the nerves you can get this corneal neuropathic pain syndrome. And the bad part about it is there's nothing to see. You can't see the nerves because they're too small.So this is analogous to small fiber neuropathy in the rest of the body. You have to do a skin biopsy in fact to diagnose those small fiber neuropathies because you can't see anything. The same in the cornea, however we have an instrument, the confocal microscope, that can help us to see these corneal nerves. And what it shows in these post-LASIK people or these corneal neuropathic people is there's disorganization of the corneal nerves instead of that nice structured richly innervated cornea you get all these little detours. The nerve just kind of squiggles around and it's not going to the right place and so if you've ever had a paper cut you know how painful a paper cut is. Those exposed nerve fibers are extremely painful even though the size of the paper cut is so small. So we can see that on the confocal microscope,we can see the corneal nerves and the disorganization of the structure. And so I think the things that are important to remember is that this corneal neuropathic pain syndrome is real. It occurs in patients who have had viral disease like herpes zoster or herpes simplex, and even after the keratopathy has gone away and the dendrite is gone and the scar is gone they might still feel the pain. We're going to be looking for the common causes: dry eye and status post-LASIK. The confocal microscope is analogous to what we're doing in small fiber neuropathies, which is a skin biopsy but the confocal is like a non-invasive biopsy of the cornea to see those nerves. And in contrast to tears and the post-LASIK thing, we're putting drops on the eyes.And normally they teach you to put the proparacaine on there,and that'll prove whether it's nerve or not.That doesn't work on these people, because the nerve endings are actually raw and you really can't make it stop. They're just firing by themselves it's not really from irritation of the cornea. So it's not like dry eye where there's actually a stimulus to that nerve,and if you put the anesthetic on it'll make it stop. These nerves are the cause of the pain. It is neuropathic pain, pain from the nerve. And so we're going to use the same kinds of medicines, gabapentin, Lyrica, the same kinds of medicines we use for neuropathic pain elsewhere. I think most people just want to know what they have. And it's analogous to the small fiber neuropathies. And the confocal microscope might help you make the diagnosis.
Date 2021-06
Language eng
Format video/mp4
Type Image/MovingImage
Collection Neuro-Ophthalmology Virtual Education Library: Andrew G. Lee Collection: https://novel.utah.edu/Lee/
Publisher North American Neuro-Ophthalmology Society
Holding Institution Spencer S. Eccles Health Sciences Library, University of Utah
Rights Management Copyright 2019. For further information regarding the rights to this collection, please visit: https://NOVEL.utah.edu/about/copyright
ARK ark:/87278/s6131scp
Setname ehsl_novel_lee
ID 1701560
Reference URL https://collections.lib.utah.edu/ark:/87278/s6131scp
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