| Identifier |
myopia_in_neuro_ophthalmology |
| Title |
Myopia in Neuro Ophthalmology |
| Creator |
Andrew G. Lee, MD; Sidra Deen |
| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (SD) Class of 2023, Baylor College of Medicine, Houston, Texas |
| Subject |
Myopia; Myopic Complications |
| Description |
Summary: • Progressive pathologic myopia is where the number keeps progressively getting bigger. o Note: Patients who have had a refractive procedure may not have an accurate myope in their chart. • Complications: o Afferent side: retinal thinning can lead to the usual myopic complications (ex. retinal detachment, Fuchs spot, choroidal neovascular membrane, Bruch's membrane breaks, and decreased night vision). o Efferent side: diplopia via the heavy eye syndrome > Heavy eye syndrome: the posterior staphyloma is getting the eye longer > globe becomes oval-/egg-shaped > improper function of the extraocular muscles > connective tissue between the superior and lateral rectus becomes stretched or displaced > eye is displaced superior temporally > esotropia or hypotropia. o Glaucomatous-type cupping and glaucomatous visual field defects. |
| Transcript |
So today we're going to be talking about myopia in neuro-ophthalmology (NOP). And as you know myopes have high minus power and once you start getting to a number like -6 or above, that's going to be a high myope. And so, we have progressive pathologic myopes where the number just keeps getting bigger and bigger myopia. And that progressive pathologic myopia can cause unexplained vision loss. And the reason you need to know about it is, it seems obvious that you would know what someone's refractive error is, but if they've had some sort of refractive procedure like LASIK or some other refractive surgery, the number that's on their chart, including having had cataract extraction, might not be their actual refraction, because they're going to be a high myope. So, they might be -1 on the chart only because they were made -1 because they had cataract surgery or a refractive procedure, but really, the eye is a progressive pathologic myopia. And so, on the afferent side, the things we are worried about are progressive thinning of the retina which of course leads to the usual myopic complications - retinal detachment, Fuchs spot, choroidal neovascular membrane, Bruch's membrane breaks. Those are the high mild things that are obvious in the retina, but it can cause unexplained vision loss and especially night vision problems because the pupil is dilating and so that will exacerbate the night myopia. And so, on the afferent side we're really worried about the progressive pathologic myopia causing decreased vision. On the efferent side it can also cause diplopia, and the reason it can cause double vision is because the eyeball in axial myopia is getting longer. So, the posterior staphyloma is getting the eye longer, and so that is what is producing the induced myopic shift. And so, one of the things that happens when you have a posterior staphyloma is the eye is not round anymore. So, in the orbit, the extraocular muscles are designed for a globe that's round, and once it starts being oval-shaped or egg-shaped, we might get displacement of the eye superior temporally at the junction between the superior rectus and the lateral rectus muscle. So, when the eye is displacing upwards superior temporally, that band of connective tissue between the superior and lateral rectus can get stretched or displaced and that can cause ophthalmoplegia because you have rotation of the muscles. Their pulley actions are not aligned in their original orientation and that we call the heavy eye syndrome. So, a high myope can get an esotropia or a hypotropia from heavy eye syndrome. This guy is too big. It gets heavy, and it displaces outside of its normal axis of rotation, and that produces the efferent presentation. In addition, the fundus might look very blond-looking and very light, and there might be a myopic crescent of tilted anomalous hypoplastic disc is often seen in myopes. And myopes are more prone to develop glaucomatous-type cupping and glaucomatous visual field defects. So, myopia is a risk factor for that. So, you should know a little bit about myopia in NOP, both on the afferent and efferent side. You cannot rely on the refraction that is listed on their chart, because they might have had a refractive procedure or a cataract extraction with intraocular lens. You should worry about progressive pathologic myopia causing progressive unexplained vision loss from the posterior staphyloma and all the retinal complications that occur from thinning of the retina. And our efferent complications related to myopia, the worst being myopic esotropia. And if you have displacement of the eye because it's not round anymore, it can cause heavy eye syndrome - a small angle esotropia and hypotropia that can mimic efferent neuro-ophthalmic disease. |
| 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, 10 N 1900 E SLC, UT 84112-5890 |
| Rights Management |
Copyright 2019. For further information regarding the rights to this collection, please visit: https://NOVEL.utah.edu/about/copyright |
| ARK |
ark:/87278/s6bk78z0 |
| Setname |
ehsl_novel_lee |
| ID |
1680609 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6bk78z0 |
