Metrizamide epidurography in dogs.

Metrizamide, a non-ionic water-soluble contrast agent, was injected into the epidural spaces of 6 dogs to see if the posterior border of the L7-S1 interspace could be outlined. Between two and six Metrizamide epidurograms were obtained on each dog. The L7-S1 interspaces were usually well outlined. No complications were experienced by the dogs. The dogs were sacrificed at intervals between 3 days and 42 days following their last epidurogram in order to examine the epidural tissues for inflammatory changes. No histologic differences were observed between the control and experimental dogs.