Arachnoiditis from myelography with iopamidol, metrizamide, and iocarmate compared in the animal model.

A new aqueous myelographic contrast media, iopamidol, was compared to iocarmate and metrizamide with respect to the risk of arachnoiditis. Macaque monkeys underwent myelography with one of the three contrast media. Twelve weeks later, the animals were restudied with myelography, then sacrificed for histologic studies of the arachnoid. Results suggest that iopamidol is safer than iocarmate and equivalent to metrizamide with respect to the risk of arachnoiditis.