Horner syndrome
Also known as: Horner-Syndrom · Horner's syndrome · Claude-Bernard-Horner-Syndrom · Sympathikusparese des Auges
Overview
What it is
Horner's syndrome is a neurological condition resulting from a disruption in the sympathetic nervous system, which controls involuntary functions like pupil dilation and facial muscle tone. It is not a disease itself, but rather a collection of symptoms that can be triggered by middle ear infections, neck trauma, or tumors along the nerve pathway. In many cases, the condition is classified as idiopathic, meaning no clear underlying cause can be identified.
How it presents
Owners will typically notice sudden changes affecting only one side of the dog's face, including a constricted pupil, a drooping upper eyelid, a slightly sunken eyeball, and a visible third eyelid. This condition can occur in dogs of any age.
Treatment
While the common unexplained form often resolves on its own without therapy, other cases require treating the underlying cause. Diagnostic investigations, which may include neurological exams or advanced imaging, generally cost between €300 and €2,000.
How it's tested
Affected breeds
Treatment cost
Estimated range of typical treatment cost. Actual cost depends on severity, clinic and region.
Frequently asked
What is Horner syndrome?
Horner's syndrome is a neurological condition resulting from a disruption in the sympathetic nervous system, which controls involuntary functions like pupil dilation and facial muscle tone. It is not a disease itself, but rather a collection of symptoms that can be triggered by middle ear infections, neck trauma, or tumors along the nerve pathway. In many cases, the condition is classified as idiopathic, meaning no clear underlying cause can be identified.
How is Horner syndrome tested?
Various clinical and genetic tests are used depending on the breed and presentation.
Which breeds are most affected?
This condition isn't tied to a specific breed in our database.