Iotrolan. The first dimeric non-ionic contrast medium for the subarachnoid space.

Iotrolan was administered to 1400 in-patients and out-patients by intrathecal injection within the framework of the clinical investigation. It was used for studies of the lumbar, thoracic, cervical and intracranial areas. It was compared with metrizamide, iopamidol and iohexol in concentrations of 190, 240 and 300 mg I/ml in controlled double-blind trials. The minimum observation periods were four days including the investigation of clinicochemical, cardiovascular and electroencephalographic parameters, and CT. The incidence and severity of all side effects after Iotrolan were much lower than those after the non-ionic monomers. No epileptogenic incidents or symptoms of a psychosyndrome were observed in any of the cases--not even after prolonged retention in the intracranial fluid spaces.