Bell, Sir Charles

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Bell, Sir Charles

Scottish physiologist and surgeon, 1774–1842.

Bell law

, Bell-Magendie law
The fact that anterior spinal nerve roots contain only motor fibers and posterior roots only sensory fibers.
Synonym: law of Magendie

Bell nerve

Long thoracic nerve; nervus thoracicus longus.
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BELL PALSY: Asymmetrical smile in patient with Bell Palsy

Bell palsy

Paralysis of the facial nerve. Bell palsy is usually caused by a reactivation of herpes simplex virus although other infections (such as syphilis or Lyme disease) are sometimes implicated. Complications may include corneal drying and ulceration and mild dysarthria. Either side of the face may be affected. Attacks recur in about 10% of cases. Synonym: Bell paralysisfacial palsy; facial nerve palsy; facial nerve paralysis; facial paralysis


Paralysis of the facial nerve typically results in an asymmetrical facial appearance. The affected patient is unable to raise one side of the mouth to smile or to wrinkle or raise the eyebrow on the same side. This peripheral nerve dysfunction is distinguished from strokes that alter facial movement by the involvement of both the forehead and the mouth. Paralysis of the face caused by strokes usually only limits movement of the oral muscles. See: illustration


Tapering doses of prednisone without antiviral drugs provide the most effective results. In addition, the affected eye should be protected from drying with artificial tears or unmedicated ointments. Some practitioners advise wearing sunglasses during the palsy or patching the eye to protect it from foreign bodies or drying.


Partial facial paralysis is usually resolved within several months. The likelihood of complete recovery after total paralysis varies from 20% to 90%.

Bell paralysis

Bell palsy.

Bell phenomenon

Rolling of the eyeball upward and outward when an attempt is made to close the eye on the side of the face affected in peripheral facial paralysis.
Medical Dictionary, © 2009 Farlex and Partners


Sir Charles, Scottish surgeon, anatomist, and physiologist, 1774-1842.
Bell law - the ventral spinal roots are motor, the dorsal are sensory. Synonym(s): Bell-Magendie law; Magendie law
Bell-Magendie law - Synonym(s): Bell law
Bell palsy - paresis or paralysis, usually unilateral, of the facial muscles, caused by dysfunction of the 7th cranial nerve. Synonym(s): peripheral facial paralysis
Bell phenomenon - upward movement of the eye on attempted eyelid closure in a patient with peripheral facial paralysis.
Bell respiratory nerve - Synonym(s): long thoracic nerve
Bell spasm - involuntary twitching of the facial muscles. Synonym(s): facial tic
external respiratory nerve of Bell - Synonym(s): long thoracic nerve
Medical Eponyms © Farlex 2012