Tumor-targeted Gamma Knife radiosurgery in patients with trigeminal neuralgia secondary to benign tumors.

BACKGROUND

Secondary trigeminal neuralgia (TN) is often associated with benign meningiomas and schwannomas. For patients who are unable to undergo surgical resection, Gamma Knife radiosurgery (GKRS) is a well-established alternative for tumor control. There is limited data on the pain outcomes in these patients undergoing tumor-targeted GKRS.

METHODS

Patients receiving tumor-targeted GKRS for a benign tumor causing secondary TN between 2005 and 2021 were identified. The Barrow Neurological Institute (BNI) pain score was documented at baseline and over the course of clinical follow-up. The study endpoint was defined as either last documented follow-up or date of additional pain procedure.

RESULTS

Seventeen patients were identified with 12 meningiomas (71%), 4 vestibular schwannomas (24%), and 1 trigeminal schwannoma (6%). Patients received either a single fraction of 12-13 Gy in 14 patients (82%) or 25 Gy in 5 fractions for 3 patients (18%). At a mean time to study endpoint of 29.5 months, 6 patients (35%) were pain free. Median time to BNI pain improvement was 4.6 months post-GKRS. One patient (6%) experienced new onset facial numbness. After the study endpoint, five patients (29%) underwent at least one subsequent balloon compression procedure for pain control. Mean total follow-up time was 61.9 months.

CONCLUSION

For patients with secondary TN due to benign lesions who are poor candidates for surgical resection, tumor-targeted GKRS has a modest effect on pain outcomes. Complication rates are also comparatively very low.