The onset of essential blepharospasm usually is heralded by an increase in blinking or squinting with progression toward repetitive forceful closure and difficulty opening the eyelids. Blepharospasm is often made worse by stress, fatigue, bright lights, watching television or driving, and social interactions. Functional blindness in the presence of an otherwise normal visual system may result. Systemic medications have limited efficacy in treating the disease. However, some patients do benefit from such therapy alone or in conjunction with other treatment modalities.
Essential blepharospasm is a diagnosis of exclusion.
The course of the disorder can fluctuate. Spontaneous remissions and exacerbations are possible, but for most patients the disease is chronic. Dry eyes, in particular, may be the cause of eyelid spasm or can aggravate coexisting essential blepharospasm. Treatment of dry eye or other ocular conditions may reduce eyelid spasm to a level that the patient can tolerate without the need for additional medications or injections. A related disorder, hemifacial spasm, involves involuntary spasms of muscles on only one side of the face.