The facial nerve consists of approximately 10,000 motor and sensory nerve fibers. These nerve fibers act as a unit allowing us to cry, smile, laugh, and frown. The facial nerve’s pathway is complex. It runs near the hearing and balance nerves, around the bones of the middle ear, the mastoid, through the salivary glands and serves the tongue, salivary glands, and tear ducts. Roughly 40,000 disorders of the facial nerve occur the United States each year.
Symptoms of Facial Nerve Disorders
- Facial twitching
- Difficulty closing or blinking one eye
- Excessive or reduced saliva
- Swelling or drooping side of the face
Causes of Facial Nerve Disorders
Although there are more than 50 known causes of facial paralysis, the most common facial nerve dysfunction is Bell’s palsy. The cause of Bell’s palsy in not known, but is thought to be due to a viral infection of the facial nerve, which affects only one side of the face. Bell’s palsy has a familial tendency. It can occur without warning or symptoms, such as facial tingling or a dry eye, and may precede the palsy, occurring a few hours before the actual facial paralysis. Other causes of facial nerve paralysis include herpes zoster oticus, acoustic tumors, multiple sclerosis, stroke, head injury, and following a middle ear surgery.
Diagnosis of Facial Nerve Disorders
Several tests are often performed to determine the degree of facial paralysis and localize the areas involved.
- Hearing evaluations
- Balance testing
- Electrical test of the facial nerve
- CT scan or MRI
Treatments for Facial Nerve Disorders
- Antiviral drugs or steroids
- Physical therapy