High-Voltage, Long-Duration PulsedRadiofrequency on Gasserian Ganglion ImprovesAcute/Subacute Zoster-Related TrigeminalNeuralgia: A Randomized, Double-Blinded,Controlled Trial

Background: Trigeminal postherpetic neuralgia is a severe neuropathic pain and often refractory to existing treatment, it develops secondary to herpes zoster-infected Gasserian ganglion. Therefore, it is important to prevent the transition of acute/subacute zoster-related pain to trigeminal postherpetic neuralgia. Despite numerous studies, the optimal intervention that reduces trigeminal postherpetic neuralgia incidence is still unknown. Objectives: This study aimed to evaluate the efficacy and safety of high-voltage, long-duration pulsed radiofrequency (PRF) on the Gasserian ganglion in patients with acute/subacute zosterrelated trigeminal neuralgia. Study Design: Prospective, randomized, double-blinded study. Setting: Department of Pain Medicine, the First Affiliated Hospital of China Medical University. Methods: Ninety-six patients with acute/subacute zoster-related trigeminal neuralgia were equally randomly assigned into 2 groups. The electrode needle punctured the Gasserian ganglion guided by computed tomography in every patient. High-voltage, long-duration PRF at 42°C for 900 seconds was applied in the PRF group (n = 48). It was also applied in the sham group (n = 48) without radiofrequency energy output. The therapeutic effects were evaluated using a visual analog scale (VAS) and the 36-Item Short Form Health Survey (SF-36) at different time points. The average dosage of pregabalin (mg/d) administrated within the first month after treatment was also recorded. Results: The postprocedure VAS scores in the PRF group were significantly lower than those in the sham group at different time points after treatment (P < 0.01). The SF-36 scores, which included physical functioning, physical role, bodily pain, general health perceptions, vitality, social function, emotional role, and the mental health index, were significantly improved at the sixth month after treatment in the PRF group compared with the sham group (P < 0.01). The average dosage of pregabalin administered (mg/d) within the first month after treatment was also significantly reduced in the PRF group compared with the sham group (P < 0.01). There were no bleeding, infection, or other severe side effects in both groups. Limitations: Single center study, relatively small number of patients. Conclusions: High-voltage, long-duration PRF on the Gasserian ganglion is an effective and safe therapeutic alternative for patients with acute/subacute zoster-related trigeminal neuralgia. Key words: Pulsed radiofrequency, zoster-related trigeminal neuralgia, visual analog scale, 36- Item Short Form Health Survey