A Case of Marcus Gunn Syndrome

ABSTRACT

Marcus Gunn reported an unusual type of congenital ptosis with a peculiar associated movement of the affected lid in 1883. This movement is thought to be due to a congenital misdirection of some of the 5th cranial nerve fibers into the branch of the 3rd cranial nerve that supplies the levator muscle. Therefore, stimulation of the jaw-winking mechanism sends excess impulses into a poorly innervated levator muscle, enough to momentarily raise the eyelid. We experienced a case of Marcus gunn syndrome in a 14 year-old boy, whose chief complaint was the drooping of the left upper eyelid which was retracted in association with opening of mouth or lateral movement of the jaw to the right side since birth.