Horner Syndrome

Horner syndrome is a neurological disorder characterized by a disruption in the nerve pathway that controls certain involuntary functions of the face and eye.

Causes

The condition occurs when there is damage to the sympathetic nervous system, which can be caused by a variety of factors, including:

Symptoms

The symptoms of Horner syndrome can vary depending on the location and severity of the damage, but may include:

  • Ptosis (drooping eyelid)
  • Miosis (constricted pupil)
  • Anhidrosis (lack of sweating) on the affected side of the face
  • Enophthalmos (sinking of the eye into the orbit)
  • Flushing or redness of the skin on the affected side of the face

Diagnosis

The diagnosis of Horner syndrome is typically made based on a physical examination and medical history. Additional tests, such as:

  • Imaging studies (e.g., CT or MRI scans) to rule out underlying conditions
  • Pharmacological testing (e.g., cocaine or apraclonidine eye drops) to confirm the diagnosis

Treatment

Treatment for Horner syndrome depends on the underlying cause and may include:

  • Addressing the underlying condition, such as treating a tumor or infection
  • Surgical correction of ptosis or other cosmetic concerns
  • Medications to manage symptoms, such as eye drops to dilate the pupil

Prognosis

The prognosis for Horner syndrome varies depending on the underlying cause and severity of the condition. In some cases, the symptoms may be temporary and resolve on their own, while in other cases, they may be permanent.

Frequently Asked Questions (FAQs)

What is Horner syndrome?
A neurological disorder affecting the nerves of the face and eye.

What are the main symptoms of Horner syndrome?
Drooping eyelid, constricted pupil, and lack of sweating on one side of the face.

What causes Horner syndrome?
Damage to the sympathetic nervous system, often due to stroke, tumor, or injury.

Is Horner syndrome painful?
Typically not painful, but may be associated with underlying conditions that cause pain.

Can Horner syndrome affect both sides of the face?
Rarely, but possible in some cases.

How is Horner syndrome diagnosed?
Through physical examination and imaging tests such as MRI or CT scans.

Is Horner syndrome a sign of a serious underlying condition?
Often indicates an underlying condition that requires medical attention.

Can Horner syndrome be treated?
Treatment focuses on addressing the underlying cause, with some symptoms being irreversible.

Is Horner syndrome contagious?
No, not contagious or infectious.

Can children develop Horner syndrome?
Yes, can occur in children due to birth defects or injuries.

Article last updated on: 25th June 2025.
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