Contrast agent overdose causing brain retention of contrast, seizures and parkinsonism.

A patient received an overdose of intravascular contrast medium and experienced protracted seizures associated with radiographic evidence of prolonged retention of the contrast agent in the cerebral cortex, basal ganglia, and thalami. This is only the second report and the first survivor of a similar neurologic syndrome occurring in a patient after contrast agent overdose. After the seizures resolved, there was a transient period of parkinsonism probably due to the toxic effect of contrast on the basal ganglia.