Repeat gamma knife radiosurgery for recurrent or refractory trigeminal neuralgia

Background: Repeat gamma knife radiosurgery (GKRS) is considered to be an effective treatment for refractory or recurrent trigeminal neuralgia (TN).
Aims: The purpose of this report was to demonstrate the relationship between the outcome of repeat GKRS and prior operative procedures on patients with recurrent or refractory TN.
Materials and Methods: A retrospective analysis was performed on 34 patients with refractory or recurrent TN who had undergone repeat GKRS; 21 patients had undergone other types of procedures, 11 of whom had undergone more than three such procedures prior to radiosurgery. The maximum dose of the repeat procedure was between 60 and 75 Gy. The mean follow-up time was 21.6 months.
Statistical Analysis Used: The log-rank test and Fisher′s exact test were used to analyze the data.
Results: Excellent pain relief was achieved in 14 patients (41.2%) after repeat GKRS, while a successful outcome occurred in 29 of 34 patients (85.3%). Better pain relief occurred in the patients who did not have a prior procedure or who had undergone fewer than three prior procedures ( P = 0.042). Twenty-four of 25 patients (96.0%) who had recurrent pain had a successful operation and five of nine patients (55.6%) who did not have significant relief of pain after the first procedure had a successful operation. The difference was statistically significant ( P < 0.01). Only four patients had mild complications.
Conclusion: It is more likely to relieve pain in patients with recurrent or refractory TN who did not have a prior procedure or who had fewer than three procedures before undergoing their first GKRS. Moreover, it seems that patients who had a good response following the initial GKRS had better results after a repeat procedure.