Vertical-Torsional Pendular Nystagmus and Convergence Spasm Due to Anti-MaTa Encephalitis

This is a 50-yo-woman with debilitating oscillopsia due to a high frequency (6 Hz) vertical-torsional pendular (quantitative eye movement recordings were performed) nystagmus. She also had intermittent double vision due to (organic) convergence spasm. Her nystagmus and spasm were thought to be related to midbrain dysfunction, although MRI showed scattered, asymmetric hippocampal, pontine, middle cerebellar peduncle and deep cerebellar white matter changes. She was found to have + anti-MaTa antibodies in the CSF, and neoplastic work-up was unrevealing