Teaching Video NeuroImages: P/Q-type voltage-gated calcium channel-associated paraneoplastic elliptical nystagmus.

A 71-year-old chronic smoker had an 11-month history of monocular followed by binocular elliptical nystagmus and oscillopsia (video at Neurology.org). MRI brain showed extensive periventricular T2 signal changes (figure) and CSF showed elevated protein to 102 mg/dL. CSF and serum paraneoplastic panel revealed elevated serum titers of anti-P/Q-type voltage-gated calcium channel (VGCC) and anti-neuronal-type voltage-gated potassium channel antibodies. An underlying malignancy was not found after an extensive investigation. The patient was treated with carbamazepine for symptomatic control, followed by high-dose IV methylprednisolone, resulting in moderate improvement. Anti-VGCC antibodies have been implicated in paraneoplastic nystagmus and small cell lung cancer is the most common associated malignancy.(1,2更多