Comparison of the short-term outcomes after low-temperature plasma radiofrequency ablation (coblation) in the Gasserian ganglion for the treatment of idiopathic trigeminal neuralgia

Background: Low-temperature plasma radiofrequency ablation (coblation) is a relatively novel technique with promising applications in neuropathic pain. A nerve stimulator was modified and connected to a plasma knife head to solve the problem of accessing the Gasserian ganglion for treatment of trigeminal neuralgia (TN). Objective: To compare the therapeutic effects and short-term outcomes of coblation vs radiofrequency thermocoagulation for the treatment of primary TN. Methods: This was a retrospective cohort study of 217 inpatients who had undergone surgical treatment for primary TN between September 2017 and June 2018 at the Xuanwu Hospital, Capital Medical University. The patients were grouped according to the procedure they selected after an informed comprehensive discussion with their surgeon: the coblation group and the radiofrequency group. Pain, numbness, and muscle atrophy were evaluated before surgery, on the day of surgery, and at 3 days, 5 days, and 3 months after surgery. Results: In the coblation and radiofrequency groups, the pain relief rates were 74.7% and 85.5% on day 1 (P=0.066), 85.3% and 97.3% on day 3 (P=0.003), and 97.7% and 88.2% at 3 months (P=0.134). At 3 months after surgery, 69.3% of the patients in the coblation group and 42.7% in the radiofrequency group had no pain (P<0.001). The multivariable analysis showed that the risk of numbness in the coblation group was independently lower than in the radiofrequency group at 3 months after surgery and (OR=0.243, 95%CI: 0.122–0.484, P<0.001). Three months after the surgery, no recurrence was found in both of the coblation group and the radiofrequency group. Postoperative pain score ≥4 points was considered as a sign of failure this series at 3 months after surgery. The failure rate in coblation group is 2.7% (n=2) and a radiofrequency group is 4.5% (n=5), but there was no statistical difference between the two groups (P=0.703). Conclusion: Coblation could reduce the risk of postoperative numbness in patients with primary TN.