Gamma Knife Radiosurgery as the Primary Intervention for Trigeminal Neuralgia

摘要

Introduction: Stereotactic radiosurgery is the least invasive surgical option for patients with trigeminal neuralgia. It has been mainly used for patients who have failed other procedures. To determine the effect of radiosurgery as the primary surgical management for patients with intractable trigeminal neuralgia, we studied those patients who had radiosurgery without any prior surgical treatments (microvascular decompression or percutaneous rhizotomy). Methods: Over a nine-year period, 480 patients underwent Gamma Knife radiosurgery for intractable trigeminal neuralgia at the University of Pittsburgh. Two hundred and eleven patients had radiosurgery as first-line treatment. One hundred and forty-nine of the 211 patients had over 6 months of follow-up. Gamma Knife radiosurgery was performed using a single 4-mm isocenter targeted to the trigeminal nerve, just proximal to its entry into the brainstem. A median maximum dose of 80 Gy was prescribed (70-90 Gy). The mean follow-up was 37 months (6-109 months). Pain relief was classified into three categories: pain-free with or without medications, partial pain relief (>50%), and little or no relief (<50%). Results: Three mouths after Gamma Knife radiosurgery, 87% of 149 patients described themselves as being pain-free. At final follow-up (mean = 37 months after Gamma Knife radiosurgery), 63% of 149 patients described themselves as being pain-free. Eleven percent (23 of 211) of patients developed numbness in the trigeminal distribution. Three percent (6 of 211) of patients developed paresthesia or dysesthesias. No patient developed corneal abrasion or keratitis. Conclusion: Gamma Knife radiosurgery is a minimally invasive surgical option for patients with trigeminal neuralgia that can be used as a primary surgery for medically refractory patients.