Does pulsed radiofrequency treatment alleviate neuropathic pain symptoms in patients suffering from occipital neuralgia?

Background and Goal of Study: According to the International Headache Society (IHS), occipital neuralgia is a non-throbbing neck pain spreading ipsilaterally to the occipito-temporo-frontal area and is relieved by injection of local anesthetics at the level of the greater and or lesser occipital nerve. In an earlier study, we showed that pulsed radiofrequency therapy (PRF) of the occipital nerves provided long-term pain relief. In the present study we investigated if PRF not only alleviates pain intensity but also the neuropathic symptoms associated with occipital neuralgia. Materials and Methods: The Ethics Committee of the Ziekenhuis Oost-Limburg approved the study. Patients fulfilling the IHS-criteria for occipital neuralgia underwent PRF of the culprit occipital nerves after a positive diagnostic block (> 50% reduction on a visual analogue scale-VAS). Target nerves were identified with the external landmarks described by Vital (1) and correct needle position was verified with electrical stimulation at 50 Hz (threshold < 0.5 V). PRF (20msec, 2Hz, 45 V, with 42°C) was performed during 4 min. Pain intensity and neuropathic symptoms were measured with a VAS and the DN4 questionnaire, respectively at baseline and 8 weeks after PRF. A paired Student t- test was used to compare data. Data are presented as mean±SEM. Results and Discussion: Twenty patients were included in the study (14 female, age: 51±3years, duration of pain: 39±12 months). Baseline VAS and DN4 scores were 7.6±0.4 and 4.5±0.4 respectively. Eight weeks after PRF, VAS and DN4 scores dropped to 4.5±0.6 (P≤0.0005) and 3.1±0.5 (P≤0.005), respectively. 45% and 30% of patients reported > 50% improvement in VAS and DN4 score, respectively, Conclusions: This study confirms our earlier results that PRF alleviates pain intensity in occipital neuralgia, and adds the fact that PRF also relieves neuropathic symptoms as measured with the DN4 questionnaire. References: 1. Vital JM, et al.: Surg Radiol Anat 1989;11(3):205-10.