Treatment of Typical and Atypical Trigeminal Neuralgia with LINAC-Based Radiosurgery: Complications, Recurrence Rates and Long-Term Treatment Outcomes.

Background/Objectives: Linear accelerator (LINAC)-based radiosurgery (SRS) is a well-established, non-invasive treatment for pharmacologically refractory trigeminal neuralgia. Despite its widespread use, long-term efficacy and recurrence rates remain incompletely defined, highlighting the need for extended follow-up studies to assess outcome durability. Methods: All patients diagnosed with trigeminal neuralgia and treated with LINAC-based SRS (60 Gy, 1-2 mm from the nerve root entry zone) between 2012 and 2019 at a single institution, a national reference center, were recruited for this study. Patients were divided into two categories based on the nature of their neuralgia: typical or atypical. Pain control was assessed using the Barrow Neurological Institute (BNI) scale at 12, 36 and 60 months, as well as time to improvement, recurrence, and adverse effects. Results: A total of 112 patients were analyzed, with a mean follow-up period of 105.14 (SD 30.65) months. Statistically significant differences in the success of pain control (BNI I-III) between patients with typical and atypical neuralgia were observed at all evaluated time points (12 months: 87.1% vs. 44.0%, 36 months: 77.0% vs. 22.0%, and 60 months: 60.7% vs. 18.0%) (p < 0.001). The mean time to improvement was 6.32 (SD 6.61) weeks (range 0-50), and the recurrence rate following initial improvement was 47.1%. Treatment-related adverse clinical events occurred in 5.4% of patients. Conclusions: Long-term pain control is achieved in refractory trigeminal neuralgia cases with LINAC-based SRS, especially in typical cases, with a low incidence of complications.