Abstract No. 580 Initial experience of CT-guided pulsed radiofrequency ablation of the pudendal nerve for chronic recalcitrant pelvic pain

Abstract

Chronic recalcitrant pelvic pain is a complex, multifactorial disorder for which directed neuropathic therapies can often provide some degree of relief. Radiofrequency ablation (RFA) of peripheral nerves has been demonstrated to provide neuropathic pain relief, with little data on pelvic nerve RFA or the use of CT guidance. Single academic center IRB-approved retrospective cross-sectional study utilizing chart review and follow-up phone calls. All patients who underwent CT-guided pudendal nerve RFA with concomitant perineural injection (PNI) during a 3-month period were included. All patients had at least one prior PNI with positive block and no prior ablation. Pulsed RFA with a 22-gauge probe using the Neurotherm NT2000iX™ (St. Jude Medical) was performed on 14 pudendal nerves in 10 patients (male:female = 3:7) with age 60 ± 14 years (mean ± SD) and BMI 24.6 ± 3. Duration (in weeks) and degree of pain relief (0-10 on VAS scale) from RFA and prior PNI were compared. Subjective change in quality of life and pain medication requirement were recorded. All 14 ablations demonstrated technical success without immediate complication. No long-term complications (up to 9 months follow-up) were identified, although one patient developed interstitial cystitis, possibly related to intraprocedural perineural contrast injection used to confirm needle position. Best reported pain scores following RFA averaged 2.1 ± 2.3, compared to 3.1 ± 2.8 and 2.4 ± 2.6 following the first and last PNI, respectively (Wilcoxon signed rank test: p = 0.11, 0.75). Duration of relief following RFA averaged 6.8 weeks ± 10.4, compared to 3.4 (SD 4.1) and 1.5 (SD 1.7) following first and last PNI, respectively. The difference between first PNI and RFA was not statistically significant (p = 0.64) but was significant between last PNI and RFA (p = 0.02). At three months post-RFA, 40% of patients reported improved quality of life and decreased pain medication usage. CT-guided pudendal nerve ablation is well tolerated and can provide pain relief similar to or better than perineural injection with the potential for longer lasting effect, particularly after the benefits of repeat PNI begin to dissipate.