Horner syndrome


Horner syndrome is a rare condition that affects the nerves to the eye and face.


Horner syndrome can be caused by any interruption in a set of nerve fibers that start in the part of the brain called the hypothalamus and travel to the face and eyes.

Sympathetic nerve fiber injuries can result from:

Rarely, Horner syndrome may be present at birth (congenital). The condition may occur with a lack of color (pigmentation) of the iris (colored part of the eye).


There may also be symptoms of the disorder that is causing the problem.

Exams and Tests

An eye examination may show:

A complete medical and nervous system (neurological) examination can show whether any other parts of the body are affected.

Other tests may include:

You may need to be referred to a doctor who specializes in vision problems related to the nervous system (neuro-ophthalmologist).


Treatment depends on the cause of the problem. There is no treatment for Horner syndrome itself.

Outlook (Prognosis)

The outcome depends on whether treatment of the cause is successful.

Possible Complications

There are no direct complications of Horner syndrome itself. However, there may be complications from the disease that caused Horner syndrome or from its treatment.

When to Contact a Medical Professional

Call your health care provider if you have symptoms of Horner syndrome.


Baloh RW. Neuro-ophthalmology. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 450.

Saper CB. Autonomic disorders and their management. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 445.

Review Date: 5/21/2012
Reviewed By: Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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