Bell's palsy

Answer 1

Definition

Bell's palsy is a temporary form of facial paralysis that occurs with damage to the nerve that controls movement of the muscles in the face.

Alternative Names

Facial palsy; Idiopathic peripheral facial palsy

Causes, incidence, and risk factors

Bell's palsy is a form of cranial mononeuropathy VII. It is the most common type of this nerve damage. Bell's palsy affects about 2 in 10,000 people.

Bell's palsy involves damage to the seventh cranial (facial) nerve. This nerve controls the movement of the muscles of the face. The cause is often not clear, although herpes infections may be involved.

Bell's palsy is thought to be linked to swelling (inflammation) of the nerve in the area where it travels through the bones of the skull. Other conditions related to Bell's palsy include:

• Diabetes
• Lyme disease
• Sarcoidosis

Symptoms

Symptoms usually start suddenly, and range from mild to severe. They may include:

• Change in facial expression (for example, grimacing)
• Difficulty with eating and drinking
• Drooling due to lack of control over muscles of the face
• Droopy eyelid or corner of mouth
• Dry eye or mouth
• Face feels stiff or pulled to one side
• Facial paralysis of one side of the face, makes it hard to close one eye
• Headache
• Loss of sense of taste
• Pain behind or in front of the ear
• Sensitivity to sound (hyperacusis) on the affected side of the face
• Twitching in face
• Weakness in face

Signs and tests

• Blood tests for sarcoidosis or Lyme disease
• Magnetic resonance imaging (MRI)
• Electromyography (EMG)
• Nerve conduction test

Other causes of cranial mononeuropathy VII, such as head injury and tumor, need to be ruled out.

Treatment

In many cases, no treatment is needed. The goal of treatment is to relieve symptoms.

Corticosteroids or antiviral (acyclovir and valacyclovir) medications may reduce swelling and relieve pressure on the facial nerve. You must take these drugs early (preferably within 24 hours of when symptoms start) for them to be most effective. However, there are no published studies showing that antiviral medications speed up or improve recovery from Bell's palsy.

Your health care provider may recommend lubricating eye drops or eye ointments to protect the eye if you cannot close it completely. You may need to wear an eye patch during sleep.

Surgery to relieve pressure on the nerve (decompression surgery) is controversial and has not been shown to routinely benefit people with Bell's palsy.

Expectations (prognosis)

About 60 - 80% of cases go away completely within a few weeks to months. Sometimes the condition results in permanent changes. The disorder is not life threatening.

Complications

• Abnormal movements, such as tears when laughing or salivation at the wrong times (synkinesis)
• Change in appearance of the face (disfigurement) from loss of movement
• Chronic problems with taste
• Chronic spasm of face muscles or eyelids
• Damage to the eye (corneal ulcers and infections)

Calling your health care provider

Call your health care provider right away if your face droops or you have other symptoms of Bell's palsy. Your health care provider can rule out other, more serious conditions, such as stroke.

Prevention

Safety measures may reduce the risk of head injury. Many of the other factors that lead to this disorder are not preventable.

References

Tiemstra JD, Khatkhate N. Bell's palsy: diagnosis and management. Am Fam Physician. 2007;76:997-1002.

Answer 2

Definition

Bell's palsy is a disorder of the nerve that controls movement of the muscles in the face.

Damage to this nerve causes weakness or paralysis of these muscles. Paralysismeans that you cannot use the muscles at all.

Alternative Names

Facial palsy; Idiopathic peripheral facial palsy; Cranial mononeuropathy

Causes, incidence, and risk factors

Bell's palsy affects about 30,000 - 40,000 people a year in the United States.

Bell's palsy involves damage to the seventh cranial (facial) nerve. This nerve controls the movement of the muscles of the face.

Bell's palsy is thought to be due to swelling (inflammation) of this nerve in the area where it travels through the bones of the skull.

The cause is often not clear. A type of herpes infection called herpes zoster might be involved. Other conditions that may cause Bell's palsy include:

• HIV infection
• Lyme disease
• Middle ear infection
• Sarcoidosis

Symptoms

Sometimes you may have a cold shortly before the symptoms of Bell's palsy begin.

Symptoms most often start suddenly, but may take 2 - 3 days to show up. They do not become more severe after that.

Symptoms are almost always on one side only. They may range from mild to severe.

The face will feel stiff or pulled to one side, and may look different. Other symptoms can include:

• Difficulty eating and drinking; food falls out of one side of the mouth
• Drooling due to lack of control over the muscles of the face
• Drooping of the face, such as the eyelid or corner of the mouth
• Hard to close one eye
• Problems smiling, grimacing, or making facial expressions
• Twitching or weakness of the muscles in the face

Other symptoms that may occur:

• Dry eye or mouth
• Headache
• Loss of sense of taste
• Sound that is louder in one ear (hyperacusis)
• Twitching in face

Signs and tests

Often, Bell's palsy can be diagnosed just by taking a health history and doing a complete physical exam.

If your health care provider is worried that a brain tumor is causing your symptoms, you may need:

• CT scan of the head
• Magnetic resonance imaging (MRI) of the head

Sometimes, you will need a test to check the nerves that supply the muscles of your face:

• Electromyography (EMG)
• Nerve conduction test

Treatment

Often, no treatment is needed. Symptoms often begin to improve right away. However, it may take weeks or even months for the muscles to get stronger, and this may be frustrating.

Your health care provider may give you lubricating eye drops or eye ointments to keep the surface of the eye moist if you cannot close it completely. You may need to wear an eye patch while you sleep.

Sometimes medicines may be used, but it is not clear how much they help. If medicines are used, they should be started right away.

• Corticosteroids may reduce swelling around the facial nerve
• Medications can fight the virus that may be causing Bell's palsy

Surgery to relieve pressure on the nerve (decompression surgery) is controversial and has not been shown to routinely benefit people with Bell's palsy.

Expectations (prognosis)

Most cases go away completely within a few weeks to months.

If you did not lose all of your nerve function and symptoms began to improve within 3 weeks, you're more likely to regain all or most of the strength in your facial muscles.

Sometimes, the following symptoms still may be present:

• Long-term changes in taste
• Spasms of muscles or eyelids
• Weakness that remains in facial muscles

Complications

Excess drying of the eye surface, leading to eye ulcers or infections.

Calling your health care provider

Call your health care provider right away if your face droops or you have other symptoms of Bell's palsy. Your health care provider can rule out other, more serious conditions, such as stroke.

Prevention

There is no known way to prevent Bell's palsy.

References

de Almeida JR, Al Khabori M, Guyatt GH, Witterick IJ, Lin VY, Nedzelski JM, et al. Combined corticosteroid and antiviral treatment for Bell palsy: a systematic review and meta-analysis. JAMA. 2009;302:985-993.

Shy ME. Peripheral neuropathies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 446.

Reviewed By

Review Date: 07/12/2010

David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Luc Jasmin, MD, PhD, Department of Anatomy, Cedars Sinai Medical Center, Los Angeles, and Department of Anatomy, University of California, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.