Bell’s Palsy

What Is Bell's Palsy?

Bell's palsy, also called facial palsy, causes sudden or temporary paralysis, or weakness, of facial muscles. The condition was first described by a Scottish surgeon, Sir Charles Bell, in the 19th century. The exact cause is unknown, but experts believe it may occur as a reaction after a viral infection, causing swelling and inflammation of the nerve that controls facial muscles (seventh cranial nerve). The weakness makes a facial droop on one side or, rarely, both sides. In addition, there is a lopsided or one-sided smile and an eyelid that resists closing. These effects usually improve within a few weeks, with complete recovery in about six months. But unfortunately, some people may continue to have some Bell's palsy symptoms for life. Rarely Bell's palsy occurs more than once in a lifetime, and the recurrence is most likely to happen within two years of the first incident.

What Causes Bell's Palsy?

The exact reason for Bell's palsy is still unknown, but the incidence of Bell's palsy is related to exposure to a viral infection, which causes inflammation of the facial nerve. The condition typically occurs when swelling or inflammation from a viral infection temporarily puts pressure on the nerve that controls facial muscles (seventh cranial nerve). This pressure damages the nerve function, making it difficult to control facial muscles or expressions. However, as the inflammation subsides, the nerve starts functioning again. Viruses that are known to cause Bell's palsy include:

• Infectious mononucleosis (Epstein-Barr).

• Cold sores and genital herpes (herpes simplex).

• Chickenpox and shingles (herpes zoster).

• Cytomegalovirus infections.

• German measles (rubella).

• Respiratory illnesses (adenovirus).

• Mumps (mumps virus).

• Flu (influenza B).

• Hand-foot-and-mouth disease (coxsackievirus).

• HIV (human immunodeficiency virus).

What Are the Symptoms of Bell's Palsy?

Bell's palsy symptoms often come suddenly and reach peak severity within 48 to 72 hours. While some people may develop mild symptoms, others may experience complete paralysis.

The symptoms start improving gradually in three weeks. Approximately 80 % of people fully recover and show no signs or symptoms of Bell's palsy within three months. Some of the signs and symptoms of Bell's palsy include: In addition to facial drooping, signs of Bell's palsy include:

• Facial drooping.

• Drooling.

• Difficulty speaking, eating, or drinking.

• Difficulty making facial expressions on the affected side.

• Twitching of the facial muscles.

• Loss of taste.

• Dry eyes.

• Facial or ear pain.

• Headache.

• Ringing in the ears (tinnitus).

• Sensitivity to sounds.

• Reduced tears and saliva production.

• Occasional facial numbness.

• Usually, one side of the facial nerve is affected, but nerves on both sides are involved in sporadic cases, causing bilateral symptoms.

What Are the Risk Factors of Bell's Palsy?

Bell's palsy can equally affect men and women of any age. However, people with the following conditions are more prone to Bell's palsy:

• Diabetes.

• Autoimmune disease.

• Family history of Bell's palsy.

• Cold sores (herpes simplex virus).

• High blood pressure (hypertension).

• Mononucleosis (Epstein-Barr virus).

• Shingles (herpes zoster virus).

• Pregnancy, particularly during the third trimester and a week post- delivery.

• Upper respiratory tract infections, such as cold and flu.

How Is Bell's Palsy Diagnosed?

There is no specific diagnostic test for Bell's palsy. Instead, the healthcare provider can diagnose the condition based on its symptoms. Other conditions, such as stroke, sarcoidosis, infections, and Lyme disease, can also cause facial paralysis that resembles Bell's palsy. So, if the symptoms are not apparent, the healthcare provider may recommend the following tests to rule out the other causes:

• Blood Tests: Blood tests can be done to rule out conditions such as Lyme disease or other infections.

• Electromyography (EMG): This test can be done to measure nerve damage and its severity. The test also helps the provider predict how quickly the person with Bell's palsy will recover.

• Magnetic Resonance Imaging (MRI) or Computed Tomography (CT): These scans are done to rule out other sources of pressure on the facial nerve, like tumors or skull fractures.

How Is Bell's Palsy Managed or Treated?

Bell's palsy often improves with or without treatment. There is no specific treatment for Bell's palsy. Still, the healthcare provider may recommend one or more of the following medications or physical therapy for symptom relief and faster recovery:

Medications:

• Oral corticosteroids, such as Prednisone, are powerful anti-inflammatory agents that reduce nerve swelling and help regain facial movement faster. Corticosteroids are most effective when they are started within 48 hours of noticing symptoms. In addition, when started early, corticosteroids improve the likelihood of complete recovery.

• Antiviral drugs, such as Acyclovir for herpes, may speed recovery, although it is still unclear how beneficial they are. When combined with oral corticosteroids, antivirals may benefit some people with Bell's palsy, but it is still unproven. Antiviral drugs, such as Valacyclovir or Acyclovir, are sometimes prescribed in conjunction with Prednisone in people with severe Bell's palsy.

• Eyedrops, such as artificial tears, help soothe dry, irritated eyes. However, if the eyelid does not close, one may need to wear an eye patch to protect the eye from injuries and irritants.

Physical Therapy:

• A physical therapist can help teach how to massage and exercise the facial muscles to help prevent paralyzed muscles from shrinking and shortening.

Surgery:

• Decompression surgery was initially used to lessen the pressure on the facial nerve and ease pressure on the nerve. But now, it is rarely performed because of the risks associated with this surgery, including permanent hearing loss and facial nerve damage.

• Facial reanimation surgery may be used to make a face look more even and restore facial movement. Such surgeries include an eyelid lift, eyebrow lift, facial implants, and nerve grafts.

What Are the Complications of Bell's Palsy?

Usually, the Bell's palsy symptoms fade after a couple of weeks, and people recover fully within six months. But severe cases of total paralysis may cause the following complications:

• Irreversible facial nerve damage.

• Synkinesis: The irregular or abnormal regrowth of nerve fibers may result in the involuntary contraction of certain muscles when trying to move other muscles. For example, when a person tries to smile, the eye on the affected side closes on its own.

• Partial or Complete Blindness of the Eye: The eye becomes dry because of the inability to close the eyelids. This happens due to excessive dryness and scratching of the clear protective covering of the eye called the cornea.

What Is the Prognosis For Bell's Palsy?

The prognosis for people with Bell's palsy is usually good. Most people with Bell's palsy recover with or without treatment. However, it is essential to notice a gradual lessening of symptoms within a few weeks. Complete recovery can take two to six months, depending on the severity of nerve damage. In rare cases, people never fully recover. Call a doctor immediately if a person experiences symptoms of Bell's palsy. Early diagnosis and treatment can help speed up recovery.

Conclusion

Bell's palsy, also called facial palsy, causes sudden or temporary paralysis, or weakness, of facial muscles. Fortunately, the symptoms gradually fade with time, with or without treatment. This is usually a temporary condition, but it can still require a lot of patience as one must wait for the facial nerves and muscles to start working again. See a healthcare provider when the symptoms first appear. Medications and physical therapy help speed up the recovery. Surgery is rarely an option for this condition.