On January 26, 2022 I just happened to glance at Daisy and had to do a double-take. Her inner third eyelid was partially covering her eye. This is normal for a dog when they are sleeping but definitely not while they are wide awake and walking around. I called my vet right away and got her an appointment for the next day. Horner’s Syndrome is scary but this is what you need to know.
Horner’s Syndrome Occurs Suddenly
Horner’s Syndrome is a common neurological disorder of the eye and facial muscles. It may be common but I had never heard of it before. It occurs without warning and symptoms include:
- Droopy eyelid
- Constricted pupil
- Eye appears sunken
- Third eyelid visible
Daisy was only displaying the visible third eyelid so I thought her eye may have gotten scratched when she and Diesel were playing and her eyelid was irritated. I never would have thought it could be a neurological disorder although now it makes sense since she does have epilepsy.
Causes of Horner’s Syndrome
There can be many reasons for Horner’s Syndrome including:
- Blunt trauma
- Tumor
- Ear disease
- Idiopathic meaning without known cause (this makes up approximately half of all cases)
Treatment
Our vet took one look at Daisy’s eye and asked “Have you ever heard of Horner’s Syndrome?” She explained what it was and wanted to take a chest x-ray immediately to rule out a tumor in her chest. Daisy’s chest x-ray was clear and so were her ears. Our vet is very practical and said she could refer us to a specialist to do an MRI to see if it was a brain tumor, but that even if it was, there would be nothing they could do. Our vet also explained that most cases are idiopathic and they never know the cause. We decided to take the wait and see approach. Daisy was acting completely normal and it didn’t seem to bother her at all.
Recovery Rate and Outlook
Just as quickly as Horner’s Syndrome occurs, it also resolves on it’s own spontaneously if it is idiopathic and there is no underlying pathological cause. It is a slow recovery and can take many months. It has now been four months since Daisy’s diagnosis and while her eye is not completely back to normal, her third eyelid is really only noticeable when she is tired.
Receiving a Horner’s Syndrome diagnosis for your dog doesn’t necessarily mean a grim outcome. The outlook can be good and the most important thing to do if you notice any of the symptoms is to make an appointment with your veterinarian right away.
*Please consult with your veterinarian regarding your individual circumstance. This post is purely our experience with a Horner’s Syndrome diagnosis.
