Blepharospasm is spasm of muscles around the eye causing involuntary blinking and eye closing.
The cause of blepharospasm is most often unknown. It affects women more than men and tends to occur in families. Rarely, blepharospasm may be secondary to eye disorders, including those that cause ocular irritation (eg, trichiasis, an inward growing eye lash), corneal foreign body,keratoconjunctivitis sicca (dry eye)) and systemic neurologic diseases that cause spasm (eg, Parkinson disease).
Symptoms are involuntary blinking and closing of the eyes; in severe cases, people cannot open their eyes. Spasms may be made worse by fatigue, bright light, and anxiety.
Treatment of blepharospasm involves injecting botulinum toxin type A into the eyelid muscles; treatment must be repeated in most instances. Anxiolytics may help. Surgery to cut the periorbital muscles is also effective but, because of potential complications, is considered only if botulinum toxin is ineffective. Sunglasses help decrease the light sensitivity that may cause or accompany blepharospasm.