| Identifier |
pupil_reaction_in_a_nlp_eye_real_or_fake |
| Title |
Pupil Reaction in NLP Eye! Real or Fake? |
| Creator |
Andrew G. Lee, MD; Nadia Ansari |
| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (NA) Class of 2022, Baylor College of Medicine, Houston, Texas |
| Subject |
Pupil; NLP; Dilation; Constriction |
| Description |
Summary: • Patient presented with a sluggish light reaction in the right pupil despite being no light perception in the right eye • The sluggish pupillary reaction to light could either be a true or false finding o If false, most commonly due to inadvertently testing the near reaction instead of the light reaction -The patient senses the light close to their eye and the pupil constricts o Could also be that the patient is not actually no light perception and they actually see light and hand motions o If true, could be amaurosis - a RAPD where the pupil does not react to light but reacts to near because the efferent motor pathway is intact • Sluggish light reaction despite no light perception could also be due to stimulation of the melanopsin ganglion cell o Melanopsin ganglion cell is responsible for seeing light and providing information for things like circadian rhythm and input to nonvisual parts of the brain • It is speculated that stimulation of the melanopsin ganglion cell is what allows RAPD to be missed in patients with clear-cut neuropathies, such as labor hereditary optic neuropathy • When confronted with sluggish reacted pupil in the setting of no light perception in one eye only, and it's not amaurotic people, consider the melanopsin ganglion |
| Transcript |
So, the other day we saw a patient who was no light perception, but my fellow said the pupil, it wasn't nonreactive - it reacted a little bit. So how can someone have a clear-cut optic neuropathy (no light perception vision, in this example, on the right), but the right pupil was not nonreactive, it was just sluggish reactive? And so, that finding of a sluggish pupil despite being no light perception could be a true finding. It could be that my fellow really detected a sluggish reaction, or it could be a false finding. That is, my fellow did not detect that finding and it was just caused by an artifact of testing. And so, let's just start with the false one. The most common cause of an inadvertent pupil reaction in someone who is a clear-cut no light perception vision from an anterior visual pathway cause, like an optic neuropathy, is that you actually were testing the near reaction. So, even though you think you're testing the light reaction, what really is happening is the patient either sees or senses that something is close to their eye (the light), and then the pupil constricts the near. However, it could be that my fellow actually measured a true sluggish reaction and they actually are truly no light perception. If they truly are no light perception, normally the pupil would be nonreactive to light, but it would react to near, and that we call amaurotic people. And amaurotic people, as the world's largest RAPD, it doesn't react to light, but it reacts to near because the efferent motor pathway is intact. However, you can have a true no light perception vision and the pupil is sluggish because there's this other ganglion cell and it's called the melanopsin ganglion cell. You need to know about this melanopsin ganglion cell because it doesn't carry the visual fiber like the other retinal ganglion cells. It is responsible for seeing light and providing information for things like circadian rhythm and input to the nonvisual parts of your brain. And so, you might have a true no light perception vision eye from a fancier visual pathway lesion like optic neuropathy, and that right pupil might be sluggish and reactive from stimulation of the melanopsin ganglion cell. This melanopsin ganglion cell layer is also clinically important because in some patients with labor hereditary optic neuropathy, even though they have a clear-cut optic neuropathy and a central scotoma and they're the right demographic (a young male with acute bilateral or sequential vision loss from optic neuropathy), they might have no RAPD. And some people have speculated that the melanopsin ganglion cell is what's allowing the RAPD to be missed in these patients. So, when you're confronted with a sluggish reacted pupil in the setting of a no light perception vision in one eye only - that could be a true finding or false finding. The most common false finding cause is that they're reacting to near. The second cause is that they're not really no light perception; they actually see light perception or hand motion. But if it's a true finding and it's not in amaurotic people, think about the melanopsin ganglion. |
| Date |
2019-10 |
| 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/s62n9srg |
| Setname |
ehsl_novel_lee |
| ID |
1469322 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s62n9srg |
