Weakness of the seventh cranial nerve, also known as the facial nerve, results in inability to move the muscles of facial expression on the side of the disease. According to the journal "Clinical Pediatrics," Dr. Charles Bell first described the nerve in 1821, and since then, weakness of that nerve has been referred to as Bell's palsy. Bell's palsy is currently defined as an unexplained weakness of the facial nerve.
Significance
Facial nerve paralysis can have a significant effect on a person's lifestyle. Bell's palsy affects facial expression, the ability to eat, verbal communication and social interaction, according to the National Institute of Neurological Disorders and Stroke. It is a condition that is immediately obvious to people who have it and to those around them. It is especially worrisome in children because the stigma of having an uneven face exposes them to school ridicule and potential developmental difficulties.
Features
Bell's palsy can affect numerous functions related to the facial nerve. According to the National Institute of Neurological Disorders and Stroke, the condition causes weakness of usually one side, affecting both the upper and lower halves of the face. A person experiences loss of taste of the front part of the tongue, sensitivity to loud noises and inability to close the eye. While another nerve controls eye opening, the facial nerve controls the muscles that open the eye. It also controls the muscles that elevate the corner of the mouth to form a smile, making the smile look uneven in those with Bell's palsy.
Misconceptions
A common misconception about Bell's palsy is that it refers to every case of facial paralysis. According to a January 2008 article by John Finsterer in the journal "European Archives of Otolaryngology," several conditions can cause people to look as though they have Bell's palsy, and many observers think to everyone with facial asymmetry has the affliction. In actuality, other diseases, such as lyme disease and mastoiditis, also can cause facial nerve paralysis. Bell's palsy, on the other hand, only describes people with facial weakness without a known cause.
Treatment
The treatment of Bell's palsy is controversial. Although physicians do not know exactly what causes the condition, the experts suspect that it is likely a viral infection of the tissues around the facial nerve. According to the National Institute of Neurological Disorders and Stroke people with Bell's palsy often receive antiviral medications such as Acyclovir because of the possible viral infection. Evidence also shows that treating this condition with steroids may improve chances of recovery.
Expert Insight
One theory about the cause of Bell's palsy is that it stems from inflammation in the tissues of the narrow canal through which the facial nerve travels. According to an article by Josef Shargorodsky in the May 2010 issue of the journal "Clinical Pediatrics," evidence shows that doing surgery to open up the facial nerve canal may improve the chances of recovery from Bell's palsy. According to a 1999 article by Dr. Bruce Gantz in the journal "Laryngoscope," patients with greater than 90 percent paralysis of the facial nerve may have a better chance of recovery if they undergo surgery to decompress the facial nerve. At that point, Gantz' article recommends surgery for those with complete or nearly complete weakness, and only if that occurred on days six to 14 after the symptoms first began.
References
- "Clinical Pediatrics"; Facial Nerve Palsy in the Pediatric Population; Josef Shargorodsky; May 2010
- "European Archives of Otolaryngology"; Management of Peripheral Facial Nerve Palsy; John Finsterer; January 2008
- "Laryngoscope"; Surgical Management of Bell's Palsy; Bruce Gantz; November 1999
- National Institute of Neurological Disorders and Strokes: NINDS Bell's Palsy Information Page
