Symptoms
The most obvious visible symptom is usually a unilateral paralysis of the facial nerve manifested by a one-sided collapse of the musculature of the face. It may be difficult to open (or close) one eye. There may be tears or drooling accompanied by a loss of taste and loss of sensory perception around the mouth. Patients commonly report a feeling of sunburn around the scalp and face. There may be significant pain.
A common consequence is emotional disturbance because of anxiety or self-consciousness about the disfigurement that the condition may cause.
Causes
- The cause is unknown but some animal studies suggest a reactivation of herpes viruses.
- Lyme borreliosis can present with a lower motor neurone facial nerve palsy. Consider it in children; if any history of tick bites (particularly, but not exclusively, within the last 30 days); if any suggestion of erythema migrans particularly of head and neck area; or if history of the progression of palsy is unusual. If that is a possibility, discuss with infectious diseases.
Prevalence
The condition affects 25 – 35 people per 100,000 per year, which is to say roughly one person in 60 during their lifetime (or about 100 people per month in Scotland). There is no significant difference in rates between men and women, though the preferred age range seems to be 30 – 45 years old.
