Long-term Effects of Ultrasound-guided Pulsed Radiofrequency Treatment for Ilioinguinal Neuralgia

Résumé du livre

LONG-TERM EFFECTS OF ULTRASOUND-GUIDED PULSED RADIOFREQUENCY TREATMENT FOR ILIOINGUINAL NEURALGIA BECKERS K., PUYLAERT M., VAN ZUNDERT J., VANELDEREN P., DE VOOGHT P., MESTRUM R. Department of Anesthesiology, Intensive Care, Emergency Care and Pain Therapy, Ziekenhuis Oost-Limburg, Genk, Belgium BACKGROUND AND GOAL OF STUDY Inguinal neuralgia (IN) is a disabling medical condition, frequently involving the ilioinguinal nerve (iiN) and often challenging to treat. A recent retrospective analysis of pulsed radiofrequency therapy (PRF) of the iiN by ultrasound (US) u2013 guided technique showed significant pain relief in 57% of IN patients after positive US-guided diagnostic block of the iiN. These data suggested PRF of the iiN is a valuable treatment for IN. In a pilot study we examined if these observations could be validated by long-term results. MATERIALS AND METHODS We analyzed 28 cases attending our pain center over the past 39 months with IN. All patients underwent US-guided diagnostic block of the iiN with 2mL of lidocaine 2%. Only patients with more than 50% pain relief were scheduled for US-guided PRF. The iiN was accessed about 2cm above the anterior superior iliac spine, perpendicular to its course, using a high-frequency linear ultrasound probe. A 23-gauge canula with thermocouple electrode was advanced until 50Hz sensory stimulation provoked paresthesias in the iiN dermatome at less than 0.50V to ensure correct position. PRF was performed during 240 seconds at 20ms pulse width and 45V, not exceeding 42u00b0C at the needle tip. Global perceived effect (GPE) was evaluated at 6 weeks, 3, 6 and 12 months. GPE >50% was considered significant. RESULTS AND DISCUSSION 28 patients were included. In 23 patients IN occurred after lower abdominal surgery (82%), 5 cases were labeled idiopathic (18%). Positive diagnostic block confirmed neuralgia of the iiN in 17 cases (61% of 28 patients, i.e. 14 post-surgical and 3 idiopathic IN). At 6 weeks, 11 of 17 patients (65%) had GPE >50%. There was still pain relief in 9 of 17 patients (53%) at 3 months, in 9 of 17 patients (53%) at 6 months and in 4 of 17 patients (24%) at 12 months. Mean time of recurrence after successful initial PRF was 10 months. In 3 of 17 patients (18%) an ongoing effect of more than 2 years still exists. CONCLUSION Treatment of inguinal neuralgia with ultrasound-guided PRF of the ilioinguinal nerve seems to be a promising modality with possible long-term pain relief. These observations must be validated in larger studies, also analyzing possible difference between in-plane and out-of-plane approach.