Transient eyelid retraction in myasthenia gravis.

Three patients with myasthenia gravis had transient retraction of the upper eyelids which usually followed prolonged upgaze and which persisted for many seconds. This could result from post-tetanic facilitation, myotonia, or a transient contracture. Retraction of this type is to be distinguished from both the long-standing unilateral retraction associated with ptosis of the contralateral eyelid and the fleeting lid twitch sign.