Benign essential blepharospasm (BEB) is a progressive neurological disorder characterized by involuntary muscle contractions and spasms of the eyelid muscles. It is a form of dystonia, a movement disorder in which muscle contractions cause sustained eyelid closure, twitching or repetitive movements.

BEB occurs in both men and women, although it is especially common in middle-aged and elderly women. It is a fairly rare disease, affecting only one in every 20,000 people in North America.

BEB begins gradually with increased frequency of eye blinking often associated with eye irritation. Other symptoms may include:

• Involuntary winking or squinting of one or both eyes
• Increasing difficulty in keeping the eyes open
• Light sensitivity

Generally, the spasms occur during the day, disappear in sleep, and reappear after waking. As the condition progresses, the spasms may intensify, forcing the eyelids to remain closed for long periods of time, and thereby causing substantial visual disturbance or functional blindness. It is important to note that the blindness is caused solely by the uncontrollable closing of the eyelids and not by a dysfunction of the eyes.

In most cases of BEB the treatment of choice is botulinum toxin injections which relax the muscles and stop the spasms. With botulinum toxin treatment most individuals with BEB have substantial relief of symptoms. Although some may experience side effects such as drooping eyelids, blurred or double vision, and eye dryness, these side effects are usually only temporary.

Other treatment options include medications (drug therapy) or surgery.