Supernumerary orbital muscle in congenital eyelid retraction.

PURPOSE Although several reports of supernumerary orbital muscles related to the levator palpebrae superioris have been published, no case has been associated with congenital eyelid retraction. This report describes an apparent causal relationship between an accessory levator muscle slip and congenital eyelid retraction. METHODS Case report and literature review. RESULTS Release of the anomalous muscle's attachment from the superior tarsal border alone resulted in resolution of the eyelid retraction. CONCLUSIONS Eyelid muscle anomalies may be a cause of congenital eyelid retraction. Ophthalmologists who treat eyelid disorders should be aware of this possibility when evaluating and operating on patients with congenital eyelid retraction.