Improved provocative test for the embolization of arteriovenous malformations--technical note.

A modified provocative test to assess the safety of embolization of cerebral and spinal arteriovenous malformations is described. The modified test uses successive amobarbital and lidocaine injections to elicit any possible neurological deficit, both mixed with radiopaque material to visualize the distribution of the anesthetic in the vessels. The modified provocative test caused no false negative results in 11 patients tested, compared to six of 27 patients with the unmodified method.