Teaching neuro images: Superior divisional oculomotor nerve palsy due to orbital lymphoma

Abstract

Divisional patterns of oculomotor nerve palsy usually indicate a lesion involving the oculomotor nerve distal to anterior cavernous sinus where the nerve divides into the superior and inferior branches.(1) A 48-year-old man showed painless ptosis and limitation of elevation, but normal pupil in the left eye (figure, A), which indicates a lesion limited to the oculomotor superior division that innervates the levator palpebrae and superior rectus. MRI revealed a nonpalpable mass in the superior portion of left orbital cavity (figure, B) that was confirmed as a malignant lymphoma (figure, C). Orbital lesions including lymphoma should be considered in divisional patterns of oculomotor palsy.(2</SUP)