September 15, 2009 "Ask Seth"

My cat has one drooping eye with an enlarged third eyelid. My vet says it is Homer's Syndrome. Is Homer's Syndrome a stroke?

Dear Seth,

My cat has one eye that is drooping with a small pupil and an enlarged third eyelid. My vet says he has Horner’s syndrome. Is Horner’s syndrome a stroke? Does his ear infection have anything to do with this?

If your veterinarian diagnosed your cat with Horner’s syndrome, then this is most likely not a stroke. Horner’s syndrome is an interruption of the sympathetic nerve that controls the eye. The disruption can be caused by trauma, tumor, eye disease, infarction, and in your case, a middle ear infection. When an ear infection causes Horner’s syndrome, the symptoms will usually be resolved in 6-8 weeks after the infection is cleared up. There is usually no treatment for Horner’s Syndrome since it is not painful and does not cause vision interference. Eye drops can be used in severe cases to assure the eye is producing enough tears to keep it wet. If you do not see improvement after 8 weeks, please see your veterinarian for further tests.

Seth Mayersohn, CVT

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