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

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 MESSAGES: This 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.