Enhanced ptosis in Lambert-Eaton myasthenic syndrome.

A patient with Lambert-Eaton myasthenic syndrome (LEMS) presented with a bilateral ptosis that improved transiently after sustained upgaze. The contralateral ptosis became aggravated on manually lifting either eyelid with and without fixation (enhanced ptosis). Enhanced ptosis is a common finding in many patients with ptosis resulting from myasthenia gravis; however, to our knowledge, this is the first description of this sign in a patient with LEMS. The phenomenon of enhanced ptosis should be sought in all patients with ptosis. Improvement of the ptosis after sustained upward gaze suggests the diagnosis of LEMS.