Definition of Horner syndrome
Horner syndrome is a rare condition that affects the nerves to the eye and face.
Causes, incidence, and risk factors
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 run to the face.
Signs and tests
An eye examination may show:
Treatment depends on the cause of the problem. There is no treatment for Horner syndrome itself.
The outcome depends on whether treatment of the cause is successful.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 6/15/2010