Eye problems often associated with multiple sclerosis (MS) are those that affect eye movement. The problems cannot be addressed with standard eyeglasses because the underlying cause is related to damage in the central nervous system (CNS).
The visual symptoms that commonly occur can be abrupt and frightening, and they can significantly interfere with everyday activities. Being knowledgeable about the available treatments and resources helps you feel a bit more prepared to manage these symptoms if they happen to you.
Several different muscles control your eye movements. In order for your eyes to move in a coordinated fashion, these muscles must be perfectly in synch with one another. The most common problems caused by incoordination in these muscles include the following:
Nystagmus: This tiny repetitive movement of the eye (generally up and down or side to side) occurs in 40 to 60 percent of people with MS. These movements can be so small that you're unaware of them, or significant enough to cause impaired vision (with objects appearing to jump around), nausea, loss of balance, and disorientation. In other words, the world can feel pretty wiggly.
The problem may resolve on its own (though it's unlikely) or it might respond to a regimen of high-dose IV or oral corticosteroids. Unfortunately, nystagmus can be pretty persistent. Some medications have been helpful for some people, including baclofen, Klonopin (clonazepam), Neurontin (gabapentin), and Transderm Scop (scopolamine), but the results aren't earth-shattering. Work is being done on optical devices to stabilize the jiggling visual environment of people with nystagmus, but these devices aren't available yet. In the meantime, a magnifying glass, large-print materials, and other low-vision aids may be useful.
Diplopia (double vision) and blurry vision: These problems are caused by eyes that don't dance well together. In other words, each eye is doing its own thing. The doctor may prescribe a course of steroids to try and resolve the problem quickly. Like nystagmus, however, these problems don't tend to respond to corticosteroids all that well. The good news is that the brain can sometimes adjust to the abnormality so that the double vision goes away.
You can patch one eye or frost one lens of your eyeglasses to eliminate the second image. It doesn't matter which eye you cover, the second image will disappear — and there's no reason to alternate the eye you patch.
The opinions about how often or how long you should use an eye patch aren't unanimous. Some physicians encourage patching only while driving or reading, in hopes that the brain will gradually adapt to the two images and merge them into one. Other doctors feel that patching is fine, no matter how often or how long you do it.
Mechanical or surgical interventions may also be helpful with the double vision. For example, a prism can be added to the surface of your eyeglasses or to the prescription itself to help align the images from your two eyes, or surgery on the muscles of the eye may help to realign your vision.
However, these interventions shouldn't be tried if your symptoms are fluctuating a lot; waiting until your vision has stabilized will avoid multiple prescription changes or the need to repeat surgery.