Percutaneous Glycerol Rhizotomies Achieves Effective 5-year Pain Reduction in Patients with Trigeminal Neuralgia

Introduction: Trigeminal neuralgia (TN) is a chronic neuropathic pain condition marked by sudden, severe, shock-like pain affecting one or more branches of the trigeminal nerve. For patients whose TN is unresponsive to medical therapy, surgical options, including percutaneous rhizotomy, are considered. This study aims to identify clinical and operative factors that predict the effectiveness of percutaneous glycerol rhizotomy in managing TN.

Methods: A retrospective analysis of percutaneous rhizotomy patients for TN over a 10-year period at a single institution was conducted. The primary outcomes in this study were immediate and long-term pain relief. Univariate and multivariable Cox proportional hazards regression model analysis and Kaplan-Meier survival analysis was conducted to assess prognostic factors for immediate and long-term pain relief.

Results: One-hundred-twenty-four patients underwent 183 percutaneous glycerol rhizotomies with adequate follow-up. Of these, 79.8% had effective immediate pain relief at their first visit, while 72.9% had effective long-term pain relief with a median time to long-term pain relief of 55.2 months (IQR: 13.7-62.4). The long-term pain relief rate was 81% at 1 year, 70% at 2 years, and 41% at 5 years. Patients with idiopathic etiologies of TN had a higher risk of ineffective long-term pain relief (HR: 2.89; 95% CI: [1.07–7.82]; p=0.03), while both positive CSF egress and cisternography confirmation during cannulation of the foramen ovale (HR: 0.22; 95% CI: [0.08-0.64]; p=0.005) and patients with effective immediate pain (HR: 0.32; 95% CI: [0.13-0.80]; p=0.014) were protective factors for long-term pain relief.

Conclusion : Percutaneous glycerol rhizotomy is an effective procedure for achieving both immediate and long-term pain relief, lasting up to 5 years in patients with trigeminal neuralgia. Patients with idiopathic pain had a higher risk of worsened long-term pain relief, whereas positive CSF egress and cisternography during cannulation, along with effective immediate pain relief at the first follow-up, were predictive of sustained long-term pain relief.