Percutaneous glycerol rhizotomies are effective in achieving immediate but not long-term pain reduction in patients with trigeminal neuralgia: A contemporary cohort analysis.

OBJECTIVES

When refractory to medical management, percutaneous glycerol rhizotomy can be a viable treatment option for trigeminal neuralgia. The aim of this study was to identify clinical and operative factors that predict immediate and long-term response to percutaneous rhizotomy in a large contemporary cohort.

METHODS

A retrospective analysis of percutaneous glycerol rhizotomy patients for trigeminal neuralgia from 2015 to 2024 with 1-year minimum follow-up was conducted. Demographic and operative data were collected. The primary outcomes of this study were immediate (at first follow-up) and long-term (at last follow-up) pain relief. Patient reported pain outcomes were scored according to the Barrow Neurological Institute (BNI) Pain Intensity Score at first and last follow-up. Prognostic factors were assessed using Cox proportional hazards regression and Kaplan-Meier survival analysis.

RESULTS

A total of 86 patients underwent 132 percutaneous rhizotomies, with a minimum follow-up of one year. Of these, 76.9 % had effective immediate pain relief (BNI I-IIIb) at their first visit with a median duration of immediate pain relief of 13 days. Despite the strong durability of immediate pain relief, only 43.4 % had effective long-term pain relief (BNI I-IIIb) with a median duration of long-term pain relief of 21.8 months. The long-term pain relief rate was 80 % at 6-months, 67 % at 1-year, 46 % at 2-years, 19 % at 5-years, and 7 % at 10-years. Furthermore, pre-operative use of carbamazepine (HR: 0.52; 95th CI [0.29-0.92]; p = 0.025) and effective immediate pain relief (HR: 0.33; 95th CI [0.18-0.59]; p < 0.001) were predictive factors for improved long term pain relief. The post-operative complication rate was 4.5 %, including 3 cases (2.3 %) of anesthesia dolorosa, and 1 case (0.75 %) of each: otalgia, herpes reactivation, and meningitis. Transient hypoesthesia was seen in 47 (40.2 %) cases, while permanent hypoesthesia was seen in 32 (28.3 %).

CONCLUSION

Percutaneous glycerol rhizotomy is a safe and effective procedure for providing immediate pain relief, however, does not offer strong long-term pain relief durability.