Signs of essential blepharospasm: a motion-picture analysis.

Motion pictures of 15 patients with essential blepharospasm were studied. Previously unrecognized signs indicated multiple cranial nerve involvement. These signs include impersistence of gaze, lid retraction, tongue thrust, head tilts, head jerks, vertical gaze spasms, and asymmetry. The sugns were also observed in a patient with bilateral blepharospasm who had a history of Bell's palsy suggesting facial nerve injury as a possible factor in blepharospasm. The presence of these signs can be explained by known neural pathways, but the site, or sites, of the lesion remains obscure. These signs may be important in assessing severity and in treatment evaluation.