Repeat gamma knife radiosurgery for refractory or recurrent trigeminal neuralgia: treatment outcomes and quality-of-life assessment

Abstract

Purpose Stereotactic radiosurgery (SRS) has become a minimally invasive treatment modality for patients with refractory trigeminal neuralgia. It is unclear, however, how best to treat patients with pain that is refractory or recurrent after initial SRS. We report on treatment outcomes and quality of life for patients treated with repeated SRS for refractory or recurrent trigeminal neuralgia. Methods and materials Between June 1996 and June 2001, 112 patients with trigeminal neuralgia were treated with SRS at the University of Maryland Medical Center. Eighteen patients underwent repeat SRS 3–42 months (median, 8 months) after initial radiosurgery because of unsatisfactory or unsustained pain relief. Patients received a median prescription dose of 75 and 70 Gy, respectively, for the first and second treatments. Self-reports of pain control were assessed with a standard questionnaire containing the complete Barrow Neurologic Institute Pain Scale. Results The median follow-up was 37.5 months (range, 12–68 months) after initial SRS and 24.5 months (range, 6–65 months) after repeat SRS. For the 18 patients in this series, the percentage of patients reporting excellent, good, fair, and poor responses after the initial and repeat SRS was 50%, 28%, 6%, and 16% and 45%, 33%, 0%, and 22%, respectively. None of the 3 patients with pain refractory to initial SRS responded to repeat SRS. Among those with recurrent pain after initial SRS, 14 patients (93%) achieved excellent or good pain outcomes after repeat SRS. The actuarial analysis revealed a 1-year recurrence rate of 22%, with no patients reporting recurrent pain after 9 months of follow-up. Two patients (11%) reported new or increased facial numbness after retreatment, which was described as bothersome by one. Repeat SRS resulted in a median 60% improvement in quality of life, and 56% of patients believed that the procedure was successful. Conclusion Despite a modest dose reduction, repeat SRS provided similar rates of complete pain control as the initial procedure, but was not effective for patients with no response to initial treatment. Repeat SRS was more efficacious for those patients who experienced longer periods of pain relief after the initial SRS. The incidence of complications was not significantly different from that observed for initial SRS. In this series, most patients had significant improvements in quality of life.