What is the Marcus Gunn Phenomenon?

Also known as the Marcus Gunn jaw wink phenomenon. This is a condition whereby the upper eyelid jerks upward involuntarily. This is caused by two or more muscles that essentially twitch and move the eyelid(s).

This condition or phenomenon is named after Marcus Gunn, who described this condition in 1883.

The Marcus Gunn Phenonmenon affects about 5% of newborns that are affected with congenital ptosis. This condition usually manifests itself during sucking, chewing or other related facial movements.

Check out Wikipedia for a full description of the Marcus Gunn Phenomenon.

Posted in: Eyelid Ptosis