Blepharospasm

Blepharospasm is a focal dystonia characterized by involuntary, repetitive contraction of the orbicularis oculi muscles, causing eyelid closure or twitching. Pathophysiology is thought to involve basal ganglia dysfunction and abnormal sensorimotor integration. Clinical manifestations include increased blinking, photophobia, and functional impairment of vision. Diagnosis is clinical, often confirmed by ruling out secondary causes such as ocular irritation or neurological disease. Management includes botulinum toxin injections as first-line therapy, with oral medications or surgery reserved for refractory cases; prognosis is chronic but manageable with ongoing therapy.