Metrizamide and the EEG: three case reports and a review.

Three patients are described who developed cerebral complications and an EEG abnormality for several days after metrizamide myelography. Clinically, the patients showed a fluctuating confusional state with dysphasia and retrograde amnesia, while their EEGs were dominated by runs of slow wave activity interspersed with frequent spikes. The runs appeared either continuously or in paroxysmal bursts. The clinical symptoms and the EEG are compatible with complex partial status epilepticus and are similar to the symptomatology of ten patients described in the literature. This rare clinical entity should be distinguished from a more common complication of metrizamide--non-specific slow wave abnormality of variable degree in the EEG with or without clinical signs. Clinical manifestations may include transient aphasia and weakness of the limbs with pyramidal signs.