Essential blepharospasm is a condition in which the eyelids close involuntarily. It usually involves both eyes. The episodes can last anywhere from a few seconds to several minutes or even hours.
Early stages of the condition involve sporadic blinking, winking or pinching of the face. In advanced stages, the spasms cause the eyelids to close forcefully to the point where vision is very limited. Advanced stages of essential blepharospasm can interfere with daily activities, such as walking down stairs, driving, operating machinery or working.