Bell's palsy
Bell's palsy: Excerpt from Professional Guide to Diseases (Eighth Edition)
Bell’s palsy is a disease of the seventh cranial nerve (facial) that produces unilateral or bilateral facial weakness or paralysis. (See Recognizing unilateral Bell’s palsy.) Onset is rapid. In 80% to 90% of patients, Bell’s palsy subsides spontaneously, with complete recovery in 1 to 8 weeks; however, recovery may be delayed in the elderly. If recovery is partial, contractures may develop on the paralyzed side of the face. Bell’s palsy may recur on the same or opposite side of the face.
Causes and incidence
Bell’s palsy blocks the seventh cranial nerve, which is responsible for motor innervation of the muscles of the face. The conduction block is due to an inflammatory reaction around the nerve (usually at the internal auditory meatus), which may be associated with infections or can result from hemorrhage, tumor, meningitis, local trauma, hypertension, sarcoidosis, Lyme disease, or infarction of the nerve.
Bell’s palsy affects all age groups and males and females nearly equally, although females are slightly more likely to develop it during their late teens and early 20s. In the United States, incidence is 23 cases per 100,000 people.
Signs and symptoms
Bell’s palsy usually produces unilateral facial weakness, occasionally with aching pain around the angle of the jaw or behind the ear. On the weak side, the mouth droops (causing the patient to drool saliva from the corner of his mouth), and taste perception is distorted over the affected anterior portion of the tongue. The forehead appears smooth, and the patient’s ability to close his eye on the weak side is markedly impaired. When he tries to close this eye, it rolls upward (Bell’s phenomenon) and shows excessive tearing. Although Bell’s phenomenon occurs in normal people, it isn’t apparent because the eyelids close completely and cover this eye motion. In Bell’s palsy, incomplete eye closure makes this upward motion obvious. Other symptoms may include loss of taste and ringing in the ear.
Diagnosis
Diagnosis is based on clinical presentation: distorted facial appearance and the inability to raise the eyebrow, close the eyelid, smile, show the teeth, or puff out the cheek. Electromyography helps determine the severity of nerve damage. Blood tests may be done to rule out acute causes (sarcoidosis or Lyme disease). If no improvement is evident within several weeks of onset, magnetic resonance imaging will rule out other causes of dysfunction.
Treatment
Treatment consists of corticosteroids to reduce facial nerve edema and improve nerve conduction and blood flow. They must be given early — within 24 hours of onset of paralysis — to be most effective. Lubricants or an eye ointment may be needed to protect the eye, as well as patching during sleep.
Special considerations
Patient care includes observation for adverse drug effects, pain relief, and emotional support.
❑During treatment with corticosteroids, watch for adverse effects, such as GI distress and fluid retention. If GI distress is troublesome, a concomitant antacid usually provides relief. If the patient has diabetes, frequent monitoring of serum glucose levels is necessary.
❑To reduce pain, apply moist heat to the affected side of the face, taking care not to burn the skin.
❑To help maintain muscle tone, massage the patient’s face with a gentle upward motion two to three times daily for 5 to 10 minutes, or have him massage his face himself. When he’s ready for active exercises, teach him to exercise by grimacing in front of a mirror.
❑Advise the patient to protect his eye by covering it with an eye patch, especially when outdoors. Tell him to keep warm and avoid exposure to dust and wind. When exposure is unavoidable, instruct him to cover his face.
❑Instruct the patient to chew on the unaffected side of his mouth. Provide a soft, nutritionally balanced diet, eliminating hot foods and fluids. Give the patient frequent mouth care, being particularly careful to remove residual food that collects between the cheeks and gums.
❑Offer psychological support.
Pictures
Book Source Details
- Book Title: Professional Guide to Diseases (Eighth Edition)
- Author(s): Springhouse
- Year of Publication: 2005
- Copyright Details: Professional Guide to Diseases (Eighth Edition), Copyright © 2005 Lippincott Williams & Wilkins.
More About Bell's Palsy
More Medical Textbooks Online about Bell's Palsy
Review other book chapters online related to Bell's Palsy:
Medical Books Excerpts
- Drooling
- "In A Page: Pediatric Signs and Symptoms" (2007)
- [ read ]
- Drooling
- "Handbook of Signs & Symptoms (Third Edition)" (2006)
- [ read ]
- Drooling
- "Professional Guide to Signs & Symptoms (Fifth Edition)" (2006)
- [ read ]
- Drooling
- "Nursing: Interpreting Signs and Symptoms" (2007)
- [ read ]
Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
» Next page: Drooling (Professional Guide to Signs & Symptoms (Fifth Edition))
Rate This Website
What do you think about the features of this website?
Take our user survey and have your say:
Website User Survey
Medical Tools & Articles:
Next articles:
Tools & Services:
Medical Articles:
Forums & Message Boards
- Ask or answer a question at the Boards:
