Bell's palsy is palsy of the facial nerve. This nerve is VII cranial nerve. It is in charge with facial movements and enervation of the skin of the face as well as the enervation of glands such as tear gland, parotid gland, submandibular and other glands which produce saliva. In Bell's palsy the facial nerve is compressed or gets swollen which results in facial muscle loosening on the affected side. According to Mayo Clinic in America more than 40.000 people are affected every year. People from 15 to 60 years old may suffer from Bell's palsy but it is most common in 40s. It may heal on its own. However it is better for patient to visit a doctor as treatment may accelerate the healing process. The symptoms may last up to few weeks or several months. The disease may reoccur in 10 % of all cases. Some patients do not recover at all.
The precise cause of the condition has not been established yet. Some say that it can develop as a consequence of nerve affecting by Vermicelli-zoster or Epstein Barr viruses. Herpes simplex virus is known to lead to Bell's palsy. Other considers the possibility of environmental factor, metabolic disorders and trauma as triggers of the disease. Tumors which compress the facial nerve and even bacterial infections can be responsible for the facial palsy.
There are groups of people who are at higher risk of developing Bell's palsy. These are people with weaken immune system (HIV or AIDS patients), pregnant women and people suffering from diabetes.
Short term complications include the paralysis of the muscles on one side of the face. This paralysis features with droopy eyelids, lack of tears, inability to blink, frown, smile or show teeth, pain in the ear, lack of taste and difficulties with eating and speaking.
The complications are serious if the remission does not happen until the third week.
Some long term complications include excessive production of tears during laughter or even improper salivation. This condition may even lead to everlasting facial disfiguration. The loss of taste may be permanent. The most severe complication is the formation of corneal ulcers and eye infections. This happens as eyelids cannot properly shut and the tear production is reduced hence the eyes stay dry and they are exposed to dust particles. So if Bell's palsy occurs the patient has to have eyes covered during sleep and to use eye drops or ointments which will be of major help in prevention from ulcers. Additionally a so called crocodile tear syndrome may develop. People with the crocodile tear syndrome produce tears while eating. This happens because the facial nerve did not regenerate properly and its branches which are in charge with tear and saliva production are mixed.
The therapy may include corticosteroids and antiviral drugs. Physical therapy is of major importance in reestablishing the nerve's function. Rarely a surgical procedure may be used to decompress the nerve.