Simultaneous loss of bilateral voluntary eyelid opening and sustained winking response following bilateral posterior cerebral artery infarction.

Spontaneous opening and closing of both eyes usually occurs in the normal awake state, unless a deliberate and voluntary attempt is made to open only one eye. We present a rare case of a male patient who was unable to open both eyes simultaneously after bilateral posterior cerebral artery infarction. He was able to close both eyes voluntarily. However, he was unable to keep both eyes open simultaneously and either the right or left eye remained closed. Upon a verbal command to open both eyes, the opened eye closed and the contralateral eye opened. When the closed eye was forced open, the opened eye closed. We thus presented a case of right-left dissociation of voluntary eyelid opening following bilateral posterior cerebral artery infarction, which was treated with botulinum toxin type A injection. Differential diagnosis to other movement disorders of the eyelids was discussed.