Marcus Gunn Jaw-Winking Phenomenon: Brief Communication.

Marcus Gunn jaw-winking phenomenon is the most common form of congenital synkinetic neurogenic ptosis. The unilaterally ptotic eyelid elevates with jaw movements due to cross innervations between oculomotor nerve and mandibular branch of trigeminal nerve. We report a case of a 12-year-old female who presented with complaint of drooping of left upper lid since birth associated with elevation of left upper lid while chewing. She was diagnosed to have Marcus Gunn jaw-winking syndrome.