Identifier |
gaze_evoked_amaurosis_lee |
Title |
Gaze Evoked Amaurosis |
Creator |
Andrew G. Lee, MD; Jonathan Go |
Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (JG) Class of 2021, Baylor College of Medicine, Houston, Texas |
Subject |
Gaze Evoked Amaurosis; Transient Vision Loss; Lesion; Tumors |
Description |
Summary: • Gaze-evoked amaurosis o Description > Transient vision loss induced by upward, downward, left, and or right gaze > A very specific finding for a lesion located in the orbit o; Pathophysiology > A tumor may compress the optic nerve, causing a stretch during extreme gaze and resulting in transient vision loss > Possible tumors: • Mass lesions o Sheath meningioma • Intraconal lesion o Cavernous malformation in the orbit • Other lesions o Schwannoma o Pseudotumor cerebri o Vascular lesion in the orbit o Other causes of fluid or mass defect o Other Presentations > Patient may have a normal eye exam > Patient may have a detectable optic neuropathy o Workup > Imaging • CT or MRI of the head and orbit • The orbit needs to be in the gaze-evoked amaurosis position. |
Transcript |
So today, we're talking about gaze-evoked amaurosis fugax. And gaze-evoked amaurosis is exactly what it says: amaurosis means blindness, the blindness is caused by your gaze. So under normal conditions, the eyeball and the optic nerve in the orbit - When you move your eyes in right or left gaze, or up or down gaze, there is sufficient play in the s-shaped optic nerve to allow that movement to occur. However, if you have a tumor in your orbit, or in the optic nerve sheath, when you move your eye, the nerve is going to get compressed. And so, when you have extreme gaze and you have a tumor, you might get the nerve on stretch, and that will cause the vision to go out transiently, induced by the gaze. This is a very specific symptom, gaze-evoked amaurosis, for the lesion being in the orbit - Most commonly, a mass lesion like a sheath meningioma or an intraconal lesion like a cavernous malformation in the orbit. However, schwannoma, pseudotumor cerebri, all sorts of things that cause fluid or mass effect in the sheath or the orbit itself, or vascular lesion in the orbit can produce gaze-evoked amaurosis. So what we need is an MRI or a CT of the head and the orbit. We need the orbit in gaze-evoked amaurosis. It's a very specific symptom. You can try to replicate the symptom in the clinic because the patients often have normal eye exams. But if they have a compressive lesion, they may also have an optic neuropathy that you can detect. And the main point is that you should do an imaging study of the orbit in anybody who has gaze-evoked amaurosis. |
Date |
2021-04 |
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/s6vj1kgg |
Setname |
ehsl_novel_lee |
ID |
1680605 |
Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6vj1kgg |