Essential blepharospasm is a focal dystonia characterized by progressive involuntary spasms of the orbicularis oculi and upper facial (corrugator and procerus) muscles. Chronic, forceful contractions of the periocular muscles is debilitating for the patient and leads to functional and cosmetic eyelid deformities. Treatment has included a variety of modalities and oral medications that are of limited efficacy. Botulinum-A injections have yielded the best temporary relief from this disorder, while the periorbital myectomy operation has been shown to give the best long-term results.
Botulinum toxin type A; Blepharospasm; Eyelids; Dystonia; Oculomotor muscles; Differential diagnosis
