Müller's muscle in the treatment of upper eyelid ptosis: a ten-year study.

Müller's muscle is a sympathetically innervated muscle that can be resected to treat upper eyelid ptosis. Candidates for the ptosis procedure are those whose upper lids elevate to a normal level following instillation of phenylephrine hydrochloride drops into their upper ocular fornix. A specially designed clamp is applied to 6.5 to 9.5 mm of conjunctiva and Müller's muscle above the superior tarsal border. A suture is run distal to the clamp, connecting conjunctiva and Müller's muscle to the superior tarsal border; then, the tissues held in the clamp are resected. In a ten-year study of this procedure, 90% of the lids with acquired ptosis and 100% of those with congenital ptosis were within 1.5 mm of the level of the opposite lid postoperatively. Only two of 232 treated lids required additional surgery.