Results of repeated gamma knife radiosurgery for medically unresponsive trigeminal neuralgia

Object. Gamma knife radiosurgery (GKS) is being increasing performed in the management of patients with medically unresponsive trigeminal neuralgia. T he authors report the results of repeated GKS in patients with recurrent fa cial pain after their initial procedure. Methods. Between April 1997 and December 1999, 100 patients with idiopathic trigeminal neuralgia underwent GKS at the authors' center. To date, 26 pat ients have required additional surgery because GKS provided no significant pain relief (15 patients) or because they had recurrent facial pain (11 pat ients). Ten of these patients underwent repeated GKS at a median of 13 mont hs (range 4-27 months). All patients undergoing repeated GKS had a signific ant reduction in their facial pain after the first procedure (eight were pa in free); no patient developed facial numbness or paresthesias. Initially, nine of 10 patients became pain free 1 to 4 weeks following repeated GKS. A t a median follow up of 15 months (range 3-32 months), eight patients remai ned pain free and required no medication. All eight patients with persisten t pain relief developed minor neurological dysfunction after repeated GKS ( six patients had facial numbness and two had paresthesias). Conclusions. Repeated GKS can be associated with a high rate of pain relief for patients with trigeminal neuralgia who experienced a significant reduc tion in their facial pain after the first operation. However, every patient with sustained pain relief after the second operation also developed some degree of trigeminal dysfunction. These findings of improved pain relief fo r patients who develop facial numbness after GKS for trigeminal neuralgia s upport the experimental data currently available.