Pasco Eye Institute

What is Bells Palsy?

Each facial nerve directs the muscles on one side of the face, including those that control eye blinking, closing and facial expressions such as smiling and frowning. Additionally, the facial nerve carries nerve impulses to the lacrimal or tear glands, the saliva glands, and the muscles of a small bone in the middle of the ear called the stapes. The facial nerve also transmits taste sensations from the tongue. When Bell's palsy occurs, the function of the facial nerve is disrupted, causing an interruption in the messages the brain sends to the facial muscles. This interruption results in facial weakness or paralysis.

What are the Symptoms?

Because the facial nerve has so many functions and is so complex, damage to the nerve or a disruption in its function can lead to many problems. Symptoms of Bell's palsy, which vary from person to person and range in severity from mild weakness to total paralysis, may include

•  twitching
• weakness
• paralysis on one or both sides of the face
• drooping of the eyelid
• drooping of corner of the mouth
• drooling
• dryness of the eye or mouth
• impairment of taste
• excessive tearing in one eye

Most often these symptoms, which usually begin suddenly and reach their peak within 48 hours, lead to significant facial distortion.

Other symptoms may include pain or discomfort around the jaw and behind the ear, ringing in one or both ears, headache, loss of taste, hypersensitivity to sound on the affected side, impaired speech, dizziness, and difficulty eating or drinking.

What Causes Bell's Palsy?

Bell's palsy occurs when the nerve that controls the facial muscles is swollen, inflamed, or compressed, resulting in facial weakness or paralysis. Exactly what causes this damage, however, is unknown.

Who Gets it?

Bell's palsy afflicts approximately 40,000 Americans each year. It affects men and women equally and can occur at any age, but it is less common before age 15 or after age 60. It disproportionately attacks pregnant women and people who have diabetes or upper respiratory ailments such as the flu or a cold.

How is it Diagnosed?

A diagnosis of Bell's palsy is made based on clinical presentation, including a distorted facial appearance and the inability to move muscles on the affected side of the face-and by ruling out other possible causes of facial paralysis. There is no specific laboratory test to confirm diagnosis of the disorder.

Generally, a physician will examine the individual for upper and lower facial weakness. In most cases this weakness is limited to one side of the face or occasionally to the forehead, eyelid, or mouth. A test called electromyography (EMG) can confirm the presence of nerve damage and determine the severity and the extent of nerve involvement. An x-ray of the skull can help rule out infection or tumor. A magnetic resonance imaging (MRI) or computed tomography (CT) scan can eliminate other causes of pressure on the facial nerve.