Learn About Horner Syndrome

What is the definition of Horner Syndrome?

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

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What are the alternative names for Horner Syndrome?

Oculosympathetic paresis

What are the causes of Horner Syndrome?

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. These nerve fibers are involved with sweating, the pupils in your eyes, and the upper and lower eyelid muscles.

Damage of the nerve fibers can result from:

  • Injury to the carotid artery, one of the main arteries to the brain
  • Injury to nerves at the base of the neck called the brachial plexus
  • Migraine or cluster headaches
  • Stroke, tumor, or other damage to a part of the brain called the brainstem
  • Tumor or infection in the top of the lung, between the lungs, and neck
  • Injections or surgery done to interrupt the nerve fibers and relieve pain (sympathectomy)
  • Spinal cord injury

In rare cases, Horner syndrome is present at birth. The condition may occur with a lack of color (pigmentation) of the iris (colored part of the eye).

What are the symptoms of Horner Syndrome?

Symptoms of Horner syndrome may include:

  • Decreased sweating on the affected side of the face
  • Drooping eyelid (ptosis)
  • Sinking of the eyeball into the face
  • Different sizes of pupils of the eyes (anisocoria) with the affected side pupil being smaller

There may also be other symptoms, depending on the location of the affected nerve fiber. These may include:

  • Vertigo (sensation that surroundings are spinning) with nausea and vomiting
  • Double vision
  • Lack of muscle control and coordination
  • Arm pain, weakness and numbness
  • One sided neck and ear pain
  • Hoarseness
  • Hearing loss
  • Bladder and bowel difficulty
  • Overreaction of the involuntary (autonomic) nervous system to stimulation (hyperreflexia)
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What are the current treatments for Horner Syndrome?

Treatment depends on the underlying cause of the condition. There is no treatment for Horner syndrome itself. Ptosis is very mild and in rare cases affects vision in Horner syndrome. This can be corrected by cosmetic surgery or treated with eyedrops. The provider can tell you more.

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What is the outlook (prognosis) for Horner Syndrome?

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

What are the possible complications of Horner Syndrome?

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

When should I contact a medical professional for Horner Syndrome?

Call your provider if you have symptoms of Horner syndrome.

Central nervous system and peripheral nervous system
What are the latest Horner Syndrome Clinical Trials?
Efficacy and Safety of Pericapsular Nerve Group (PENG) Block for Patients Undergoing Shoulder Surgery

Summary: Significant pain after shoulder surgery induce worse experience and may delay recovery of patients undergoing shoulder surgery. Interscalene brachial plexus block (ISB) is a common and rapid-onset procedure for pain control of patients undergoing shoulder surgery. However, the high incidence of adverse events such as hemidiaphragmatic paresis, horner syndrome after interscalene block threatened pa...

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Automated Pupillometry for the Diagnosis of Horner's Syndrome in Acute Stroke Patients Due to Carotid Artery Dissection

Summary: Horner's syndrome (HS) is a result of interruption of the sympathetic innervation to the eye and ocular adnexa, which can occur due to carotid artery dissection (CAD), along which the sympathetic nerve fibers travel to reach the eye. Dissection of the carotid artery is one of the etiologies for ischemic stroke in young patients. In our current study, we will explore the diagnostic accuracy of auto...

What are the Latest Advances for Horner Syndrome?
The long-term efficacy of left cardiac sympathetic denervation in long QT syndrome.
Redo surgery for neurogenic thoracic outlet syndrome is useful.
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Intracapsular enucleation of cervical schwannomas via retroauricular hairline incision.
Who are the sources who wrote this article ?

Published Date: April 25, 2022
Published By: Joseph V. Campellone, MD, Department of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

What are the references for this article ?

Balcer LJ. Pupillary disorders. In: Liu GT, Volpe NJ, Galetta SL, eds. Liu, Volpe, and Galetta's Neuro-Ophthalmology. 3rd ed. Philadelphia, PA: Elsevier; 2019:chap 13.

Norse AB. Diplopia. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 17.

Thurtell MJ, Rucker JC. Pupillary and eyelid abnormalities. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 17.