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Genetic and Rare Diseases Information Center (GARD)

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Horner's syndrome

Other Names for this Disease
  • Bernard-Horner Syndrome
  • Oculosympathetic Palsy
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Your Question

My daughter sustained an injury which required her to be placed on an ECMO machine for several days. The machine damaged a nerve which caused Horner syndrome. Can you provide me with more information about this condition?

Our Answer

We have identified the following information that we hope you find helpful. If you still have questions, please contact us.

What is Horner's syndrome?

Horner's syndrome consists of miosis (constriction of the pupil), ptosis (drooping of the upper eyelid), anhidrosis (absence of sweating of the face), and enophthalmos (sinking of the eyeball into the eye socket).[1][2][3]  It is caused by injury to the sympathetic nerves of the face. In rare cases, Horner's syndrome is congenital (present from birth) and associated with a lack of pigmentation of the iris (colored part of the eye).[1]
Last updated: 3/6/2012

What symptoms are associated with Horner's syndrome?

Symptoms typically include drooping of the eyelid, constriction of the pupil, sinking of the eyeball into the face, and decreased sweating on the affected side of the face. These symptoms may vary.[1][2][3] Other symptoms which may be seen include the inability to close the eyelid, a transient decrease in intraocular pressure, changes in tear viscosity (thickness), absence of horizontal eyelid fold or crease in the drooping eyelid, and red conjunctiva.[3][4] Other symptoms associated with the underlying cause may also occur.

The most reliable clinical sign of Horner's syndrome is the anisocoria (unequal size of the pupils).[4] Heterochromia iridium (i.e., a relative deficiency of pigment in the iris (colored part of the eye) of the Horner's side, is usually present when the syndrome is congenital or caused by a lesion that has occurred before the age of 1-2 years.[3] Also, cluster headaches (tearing, congestion, and pain around one eye) is associated with intermittent Horner's syndrome.[4]
Last updated: 3/6/2012

What causes Horner's syndrome?

There are many potential causes of Horner's syndrome. It can be caused by any interruption of the sympathetic nerve fibers, which start in the hypothalamus and run via the upper spinal cord near the carotid artery to the face. Sympathetic nerve fiber injuries can result from a stroke in the brainstem, injury to the carotid artery, a tumor in the upper lobe of the lung, and cluster headaches.[1]

Horner's syndrome can also be caused by the following [3][4]:


Last updated: 3/6/2012

How is Horner's syndrome diagnosed?

The physical signs of Horner's syndrome may be so subtle that they often go undetected. An ophthalmologist may confirm the diagnosis by special eye tests.[5]  In addition, a careful neurological exam may be necessary to find the cause by determining which, if any, other parts of the nervous system are affected. Tests may include[1]:
Last updated: 3/6/2012

How might Horner's syndrome be treated?

Treatment depends on the underlying cause. There is no specific treatment for Horner's syndrome itself.[1] In many cases, no effective treatment is known.[4]
Last updated: 3/6/2012