Periodic alternating nystagmus with circumscribed nodular lesion

Abstract

A 44-year-old man developed dizziness and oscillopsia after surgical resection of ependymoma in the fourth ventricle, which had manifested with headache and vomiting (figure, A). Examination disclosed newly developed jerky horizontal nystagmus after the surgery. The nystagmus changed its direction periodically with a brief transition period (figure, B and C, video). Follow-up MRI disclosed discrete lesions in the nodulus and left …