Bell's palsy
Bell's palsy is a condition characterized by the sudden weakening or paralysis of facial muscles, typically affecting one side of the face due to damage to the seventh cranial nerve. The exact cause is often linked to viral infections, particularly the common cold virus or herpes, but can also be associated with other factors such as chronic middle ear infections, Lyme disease, and head trauma. Symptoms may include an inability to close the affected eye, drooping of the eyelid and mouth, increased sensitivity to sound, and impaired taste, among others. The onset of symptoms is usually abrupt and tends to peak within the first 48 hours.
Most individuals experience significant improvement within two weeks, with total recovery generally occurring within three to six months. Treatment options may include antiviral medications, corticosteroids like prednisone, and supportive therapies such as facial exercises and moisture protection for the eye. While Bell's palsy can affect anyone, it is more commonly seen in individuals between the ages of 15 and 60, with increased susceptibility in diabetics and pregnant women. Ongoing research aims to better understand the nervous system and improve treatment methods, with some studies exploring the potential benefits of methylcobalamin and acupuncture in recovery.
Bell's palsy
ANATOMY OR SYSTEM AFFECTED: Ears, eyes, head, mouth, muscles, nerves
DEFINITION: A weakening or paralysis of facial muscles caused by damage to the seventh cranial nerve.
CAUSES: Damage to seventh cranial nerve, immune system weakness from common cold or herpes, chronic middle ear infection, sarcoidosis, Lyme disease, high blood pressure, tumors, head trauma
SYMPTOMS: Weakening or paralysis of facial muscles on one side, with inability to close eye, frequent tearing and dryness of eye, drooping eyelid and mouth, drooling, increased sensitivity to sound, ringing in ear, taste impairment, jaw pain, impaired speech, headache, dizziness
DURATION: Improvement within two weeks, total recovery within three to six months
TREATMENTS: Antiviral drugs (acyclovir, famciclovir, valacyclovir), prednisone, moist heat, facial massage and exercise, B vitamins
Causes and Symptoms
The most likely cause of Bell’s palsy is a weakened produced by the common cold virus or herpes viruses. The condition has also been associated with chronic middle ear infection, sarcoidosis, Lyme disease, high blood pressure, tumors, and trauma to the head. A diagnosis of Bell’s palsy is made from facial appearance and weakness, blood tests, electromyography to confirm nerve damage, and magnetic resonance imaging (MRI) or computed tomography (CT) to assess any pressure on the facial nerve.
In 99 percent of cases, Bell’s palsy produces paralysis on only one side of the face. Other symptoms may include an inability to close the eye on the affected side, frequent tearing from that eye, dryness of the affected eye, drooping of the eyelid and mouth, drooling, increased sensitivity to sound and ringing in the affected ear, impairment of taste, jaw pain, impaired speech, headache, and dizziness. Typically, the symptoms appear rather suddenly and peak within the first forty-eight hours after onset. Most patients experience dramatic improvement within two weeks, and most recover totally within three to six months after onset.
Treatment and Therapy
Various treatments can be effective if administered within seven days after onset. Antiviral drugs such as acyclovir, famciclovir, or valacyclovir cause the virus to run its course faster by binding viral enzymes so that the harmful cells cannot replicate. Prednisone, a synthetic hormone that mimics the natural steroid cortisol produced by the body, is also administered to help reduce swelling and the inflammation compressing the seventh cranial nerve.
The application of moist heat can help reduce pain and discomfort. The affected eye should be kept moist to protect it from debris and injury. Facial massage and exercise may help prevent the permanent shrinkage of facial muscles. Since vitamins B1, B6, and B12 are essential for proper nervous system functioning, a B-complex vitamin is often prescribed. Ample rest is necessary to restore the immune system.
Perspective and Prospects
First described in the nineteenth century by Scottish surgeon Sir Charles Bell, Bell’s palsy affects approximately forty thousand Americans each year. It can occur at any age but is less common before age fifteen and after age sixty. Diabetics are particularly susceptible to the condition, as are pregnant women, particularly during the last trimester.
No cure has been found for Bell’s palsy. Research focuses on achieving a better understanding of how the nervous system works, developing methods of repairing damaged nerves and restoring full use of injured areas, and finding ways to prevent nerve damage. Methylcobalamin, an essential component in the process of building nerve tissue, shows promise for treating Bell’s palsy. Acupuncture may also help one recover from Bell's palsy.
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