Early radiosurgery provides superior pain relief for trigeminal neuralgia patients.

Abstract

We evaluated factors associated with better outcomes after stereotactic radiosurgery (SRS) when it was performed as the first surgical procedure for medically refractory trigeminal neuralgia. A total of 121 patients (median age 72 years) with medically refractory pain and no prior surgery underwent Gamma Knife SRS as their initial surgical procedure for trigeminal neuralgia. Using a single 4-mm isocenter, patients received an average maximum dose of 80 Gy, delivered to the trigeminal nerve target defined by intraoperative MRI. The median follow-up was 36 months. Pain relief (Barrow Neurological Institute [BNI] score I-IIIa) was achieved in 107 (88%) patients at a median time of 1 month. Patients who underwent earlier SRS (within 3 years of pain onset) had a shorter interval until pain relief (1 week, p < 0.001), had a longer interval of pain relief off medication (BNI-I, p < 0.001), and had a longer duration of adequate pain control (BNI-I-IIIa, p < 0.001). Median pain-free intervals for patients who underwent SRS at 1, 2, 3, and more than 3 years after trigeminal neuralgia diagnosis were 68, 37, 36, and 10 months, respectively. Patients who responded to SRS within the first 3 weeks after SRS had a longer duration of complete pain relief compared to those with longer response times (p = 0.001). Fifteen patients (12%) reported new sensory dysfunction after SRS. Early SRS as the initial surgical procedure for management of refractory trigeminal neuralgia was associated with faster, better, and longer pain relief when compared to late SRS. This study provides Class IV evidence that in patients with medically refractory trigeminal neuralgia, early stereotactic radiosurgery as the initial procedure provides faster, better, and longer pain relief.