Congenital Paradoxical Lower Eyelid Retraction With Upgaze due to an Anomalous Extraocular Muscle.

Congenital anomalous orbital structures are rare and associated with strabismus, globe retraction, and dystopia. The authors present a case of congenital paradoxical right lower eyelid retraction with upgaze due to an anomalous extraocular muscle in a 17-year-old, healthy, female patient. Orbital computed tomography showed an intraconal, inferolateral soft-tissue band extending from the orbital apex to the inferior oblique muscle and lower eyelid. There was resolution of lower eyelid retraction and exposure symptoms after resection of the anterior portion of the fibromuscular band from the lower eyelid retractors and eyelid elevation with ear cartilage. To the authors' knowledge, this case is the first to report anomalous orbital structure as a rare cause of congenital paradoxical lower eyelid retraction, which can be improved with resection.