| Identifier |
Transient_Vision_Loss_1080p_Lee |
| Title |
Transient Vision Loss - Monocular vs Binocular |
| Creator |
Andrew G. Lee, MD; Muhammad Shamim |
| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (MS) Baylor College of Medicine, Houston, Texas |
| Subject |
Monocular Vision Loss; TBL; TMVL; Binocular Vision Loss; Amaurosis Fugax |
| Description |
Dr. Lee lectures medical students on the subject of transient vision loss. |
| Transcript |
Today we are talking about TBL which is transient vision loss.And one of the very first things you have to decide is whether you're dealing with a transient monocular vision loss, a TMVL, or transient binocular orbilateral vision loss which is a TBVL. So in the monocular version that is sometimes called amaurosis fugax (but really Amaurosis fugax means fleeting blindness so it depends whether you're a lumper or splitter in terms of whether you would consider both of these to be a form of amaurosis). For you guys, the reason it's important is the transient monocular vision loss, the thing you're most worried about is ipsilateral hemodynamically significant carotid disease. And the features that suggest that someone who has a transient vision loss episode that is monocular is due to ipsilateral hemodynamically significant carotid disease is whether or not it is altitudinal. And altitudinal means it's like a curtain coming down or it can be hemianopic which is the curtain coming from the side. If it's hemianopic, that's almost always someone who thinks it's monocular but it really is bilateral. But they usually only notice the eye with the temporal field defect. However if it's altitudinal either in its onset or disappearance, lasts seconds to minutes at a time, or it has retinal claudication (which is like jaw claudication or limb Claudication)in that the vision loss was precipitated by using your retina in this case light. So when you have limb claudication, the pain in your leg is caused by walking. If it's jaw claudication,the pain in your jaw is caused by chewing. But in retinal claudication, the vision loss is caused by light hitting the photoreceptors and causing the vision to go out. So these three are the top three things that I'm going to be looking for in someone who has suspected ipsilateral hemodynamically significant carotid disease. Causing the transient monocular vision loss,the highest odds ratio (4.8) is retinal claudication.This altitudinal thing is like a 3X. The seconds the minutes, this is probably 2x odds ratio. If they can't tell you anything about their vision loss, unknown mode of onset, unknown duration, that actually has a lower odds ratio, less than 1 (it's like .2). So it's almost as if they didn't, they didn't talk to you, which would be 1.0 plus they gave you some information that was less likely to be stenosis of their carotid. And the thing that is less likely to be carotid disease [is] if they can't tell you anything (unknown duration, don't know which eye it is, don't know how long it lasted). So that is very reassuring that it might be something benign. The transient bilateral vision loss is not going to be the carotid because it's really hard to get both carotids to go out at the same time unless it's a hypoperfusion event like cardiac arrest. In bilateral [vision loss], that's vertebral basilar system. The vertebral basilar system, So as you know,the vertebral arteries meet in the basilar artery and then become the terminal posterior cerebral arteries. And so if you have a dissection or a thrombus in the vertebral artery,it can fly up and go to either or both PCAs and that will cause tunneling of their vision, or homonymous hemianopsia,or complete blindness. That is a cortical visual impairment.You should also be thinking about migraine in this setting and seizure in the occipital cortex. But if it's going to be vascular, you're really thinking about vertebral Basilar disease (either dissections or Thrombo-embolic disease from the vertebral). And it could still be cardiac for either the monocular or the binocular. And so the stroke team is going to take this person and do an echo and an EKG and hold your monitor and blood tests. So in both the monocular and the bilateral transient vision loss,we're really going to have to do the amaurosis fugax workup [and] the stroke workup. That means looking at their heart,looking at the artery in your neck,and if its bilateral,looking at the posterior circulation[and]vertebral circulation. Think about migraine and seizure.And if they can't tell you diddly squat,that actually has a lower odds ratio for something bad. That usually means it's dry.Something like that.So we should keep a diary to try and get the details out of this person.You need to know a little bit about transient vision loss but the most important first piece of information is whether it's one eye or both eyes. |
| 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/s64n54bb |
| Setname |
ehsl_novel_lee |
| ID |
1701590 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s64n54bb |
