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Hypoglossal Nerve Disorders

By

Michael Rubin

, MDCM, New York Presbyterian Hospital-Cornell Medical Center

Last full review/revision Sep 2020| Content last modified Sep 2020

Disorders of the 12th cranial nerve (hypoglossal nerve) cause weakness or wasting (atrophy) of the tongue on the affected side. This nerve moves the tongue.

  • Hypoglossal nerve disorders may be caused by tumors, strokes, infections, injuries, or amyotrophic lateral sclerosis.
  • People with hypoglossal nerve disorder have difficulty speaking, chewing, and swallowing.
  • Doctors usually do magnetic resonance imaging and/or a spinal tap to identify the cause.
  • The cause is treated.

(See also Overview of the Cranial Nerves.)

Causes

Causes of hypoglossal nerve disorders include

  • A tumor or bone abnormality at the base of the skull
  • A bulge (aneurysm) in an artery at the base of the brain
  • A stroke
  • Infection of the brain stem
  • An injury to the neck, as may occur after surgical removal of a blockage from an artery in the neck (endarterectomy)
  • Amyotrophic lateral sclerosis (Lou Gehrig disease)

Symptoms

The tongue becomes weak on the affected side and eventually wastes away (atrophies). As a result, people have difficulty speaking, chewing, and swallowing. Damage due to amyotrophic lateral sclerosis causes tiny, subtle twitching movements (fasciculations) on the surface of the tongue.

Diagnosis

  • Magnetic resonance imaging
  • Sometimes a spinal tap

Magnetic resonance imaging (MRI) is usually done to look for a tumor or evidence of a stroke.

A spinal tap (lumbar puncture) may be necessary if cancer or infection is possible.

Treatment

  • Treatment of the cause

Treatment of hypoglossal nerve disorders depends on the cause.

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