Long-term outcomes and predictors of percutaneous radiofrequency thermocoagulation of Gasserian ganglion for maxillary trigeminal neuralgia: a retrospective analysis of 1070 patients with minimum 2-year follow-up

Abstract

Objective: To estimate long-term efficacy and safety for maxillary trigeminal neuralgia (TN) using radiofrequency thermocoagulation (RFT) targeted on Gasserian ganglion, and to identify the factors which may influence outcomes after procedure.

Methods: From 2006 to 2019, 1070 patients underwent RFT for the treatment of medically refractory maxillary TN was included. All patients were followed up for at least 2 years. Outcomes and complications were recorded and analysed. Logistic regression analysis was employed to identify risk factors of long-term pain recurrence. Prognostic value was calculated from receiver-operating characteristic curve (ROC).

Results: Longitudinal analysis was taken place for 97 non-responders (9.1%) with ineffective pain relief, 253 responders (23.6%) with pain recurrence and 720 responders (67.3%) without pain recurrence. The median pain-free survival (PFS) was 112.0 months (95% CI: 107.5, 116.5). The pain-free rates were 89.9% (95% CI: 88.0-91.8%) at 1 year, 83.8% (95% CI: 81.5-86.1%) at 2 years, 75.4% (95% CI: 72.7-78.1%) at 5 years and 70.2% (95% CI: 67.4-73.0%) at 10 years. Atypical facial pain (HR = 5.373, 95% CI: 2.623-11.004, p < .001), previous facial numbness (HR = 5.224, 95% CI: 3.107-8.784, p < .001) and poor initial response to medication (HR = 3.185, 95% CI: 2.087-4.860, p < .001) were independently associated with long-term pain recurrence. Patients with prognostic index (PI) > 0.25 were identified as high-risk for recurrent TN (HR = 5.575, 95% CI: 3.991-7.788, p < .001). New and worsen facial hypoesthesia was recorded in 77.9% of patients corresponding with BNI score II-IV, and 18.7% reported improved sensation. Severe complication incidence including troublesome dysesthaesia, keratitis and masseter weakness was higher in 80 °C group.

Conclusions: Favourable outcomes were achieved in terms of long-term pain relief and complications rate after RFT for maxillary TN. Patients with typical facial pain, normal facial sensation, and good initial response to medications may have favourable long-term outcomes.Key messagesThis is a retrospective analysis of radiofrequency thermocoagulation (RFT) targeted on Gasserian ganglion for the treatment of maxillary trigeminal neuralgia (TN) during long-term follow-up. Recurrence-free survival among a large sample was assessed and risk factors associated with long-term pain recurrence was identified. It has been verified that inadvertent damage of ophthalmic and mandibular division causes ophthalmic and masticatory complications. Therefore, a more precise needle tip position and thermocoagulation using a relatively low temperature was recommended.

Keywords: Maxillary trigeminal neuralgia; facial numbness; masseter weakness; ophthalmic complications; pain-free survival; radiofrequency thermocoagulation.

Figure 1.

Puncture of Gasserian ganglion for on V2 selective RFT through FO approach. (a) The puncture needle entering the right FO along a quarter of the inner side wall of FO on the coaxial image of FL. (b) The tip of the needle is placed in middle third between the clivus and skull base on the lateral image of FL. V2: maxillary nerve; FO: foramen ovale; FL: fluoroscopy.

Figure 2.

(a) Kaplan–Meier survival curve for patients with maxillary division TN after RFT over a 14-year follow-up period. The median pain-free survival was 112.0 months (95% CI: 107.5, 116.5). Tick marks illustrated censored observations. (b) Kaplan–Meier survival curves for patients in high-risk group and low-risk group after RFT over a 14-year follow-up period. Patients with PI > 0.387 had a higher risk for pain recurrence with HR = 5.575 (95% CI: 3.991–7.788, p < .001). Tick marks illustrated censored observations. TN: trigeminal neuralgia; RFT: radiofrequency thermocoagulation; CI: confidence interval; PI: prognostic index.