Double Vision after Neurological Event
Many patients will complain of double vision following a stroke, brain injury or concussion. Over 50% of acquired brain injury patients will have eye movement problems. These problems can slow down the rehab process but doing the wrong thing, can make it worse.
Did this person have diplopia prior to the event? 40% of patients over 60 have distance eye movement problems that they may or may not be aware of. This number goes up as they age to 50 percent 80+ years old. Do their current glasses have prism?
Is the patient wearing progressive glasses? Are their glasses fit properly? The narrow focusing channel in progressives can increase visual complaints after a neurological event as the eyes may not work together as they once did.
First we should assess cardinal gaze as described here. First binocularly then monocular to look for cranial nerve palsies. Next, the worth 4 dot can tell if the patient is seeing double or have they begun to suppress the mis-aligned eye.
Suppression is a strategy of the brain to eliminate bad visual information. If one eye is better than the other, or one eye is not aligned, the brain will not pay attention to that eye eliminating the erroneous information. NEVER BEGIN PATCHING TO IMPROVE A SUPPRESSED EYE WITHOUT AN OPTOMETRIST OR OPHTHALMOLOGIST ORDER!! Without correction of the error (surgery/recovery of the eye movement or best correction for both eyes) the patient will see double if one attempts to “wake up” the offending eye. Suppression will generally begin after just a day few days. Once corrected, they patient will resume binocular vision.
In some cases, exercising the eyes individually may help improve a nerve palsy.
Alternating a patch from eye to eye is the most on-the-spot fix but can cause problems of its own as reduced magnocellular input can affect balance and gait.
Applying sector occlusion may also be ordered by the doctor. In this process, a small of piece is place on the glass to block vision in the eye when it becomes misaligned. A complete explanation of this requires more than a blog post.
Complete assessment by an ophthalmologist or optometrist should be part of the discharge instructions.