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Tuesday, February 7, 2012

Horner's syndrome (take 2)

By far, my first post on Horner's has received the most comments. Horner's syndrome is not a disease but rather a constellation of clinical signs resulting from sympathetic (not empathetic!) pathology that courses circuitously from the brain to the eye after running down a portion of the upper spine. If I were to run down the street after you, brandishing a knife or other threatening weapon, your sympathetic nervous system would kick in: your pupils will dilate, your eyes would bulge out, your eyelids wide open, and you'd run like heck. In animals (and people) with Horner's syndrome, the sympathetic branch to the eye is disrupted. Therefore, they exhibit a droopy eyelid, miotic (constricted) pupil, a sunken eyeball, and a prolapsed third eyelid (we lost our third eyelid a long time ago so don't worry if you don't have one).
Most cases of Horner's are idiopathic - we don't know why it happens, not due to anything serious, and tends to disappear after a few weeks or months. That said, not all cases can be dismissed without concern. Causes of Horner's syndrome are myriad: middle ear infections, polyps, tumors/cancer, hypothyroidism, spinal disease, thoracic (chest) disease, and more. Even pulling too hard on a dog's leash and ear cleaning (especially in cats) can cause Horner's. Pets showing signs of Horner's syndrome should have a thorough physical exam done by a veterinarian. Keep posting and thanks for all the comments!

(in virtually all cases, unlike dogs, Horner's syndrome in cats has a primary cause. Photo from


gigi said...

My 7 month old male Yorkie was neutered on a Thursday Februrary 23, 2012. His right eye was covered in blood. They said it was due to removal of 4 decidual teeth. He also got his back dew claws removed.
His right eye was droopy and the vet said could be anesthetic. I didnt' wait and went to another vet after the one who performed the surgery said I may have scratched his cornea by cleaning the blood off with warm water and a baby washcloth. The vet we went to afterwards prescribed Fucithalmic and tested his eyes. No cornea scratches. Eye was responding as it should. Third eylid was in tact and active. Told us if not better after a few days with the drops to bring him back. His eye remained droopy and the vet performed further tests and diagnosed Horner's Syndrome. He wants us to continue with the Fucithalmic. My question is this ....Could the surgery have caused this....medication or not enough lubrication in eye during surgery? And I read online that the drops to treat Horner's syndrome best would be a 2.5% phenylephrine. Any advice.


TorontoVet said...

The vast majority of Horner's syndrome in dogs is idiopathic (no discernible cause). Some dogs, but more often in cats, wake up from anesthesia with Horner's syndrome. The vast majority of these having had their ears cleaned while under general anesthesia. The previous vet did nothing wrong. It happens so infrequently and almost always gets better within a few weeks or months, and does not affect the pet.
Phenylephrine is used to test the localization of the lesion involving Horner's syndrome. In my opinion, that would be entirely academic at this time. Take a breath and be patient!

Allison O'Maley said...

My cat is showing signs of Horner's syndrome this morning, in what would be the second time in less than two years. The first time it went away in a few weeks, and the vet couldn't find anything wrong. I took her to another vet a few months later when I realized she had an ear infection. Could this be the ear infection returning, or possibly the ear infection is worse than originally thought? No one seemed to be concerned when I mentioned Horner's syndrome, as if they weren't familiar with the term. I'm very concerned that something deeper is causing this and want to know that whatever vet I take her to takes this seriously! What should I do/say? I just noticed it this morning, but it seems to have come on rather suddenly.

Dr. Bob Turrou said...

Cats sometimes can have both (or sometimes just one)of their 3rd eyelids prolapse up over their eyes for an unknown reason so it can look somewhat like Horner's Syndrome in both eyes. The cause is unknown and usually resolves by itself in 2-6 weeks.
What's interesting about this syndrome is that the disease and cause was actually written up in a veterinary journal in the early 60's, I think it was, and called Bird Watcher's Disease. The author thought that cats crouching down and looking up while hunting birds got the disease from the posture of their eyes! I'm glad that journal articles are more scientifically written and reviewed these days.

Dr. Bob Turrou

Anonymous said...

I have a kitten born with one eye sunk in an smaller than the other hes awsome but we worry. Any ideas on what it is?