Percutaneous CT-Guided Cryoablation of the Bilateral Pudendal Nerves for Palliation of Intractable Pain Related to Pelvic Neoplasms

Abstract

Objectives: The purpose of this report is to describe the effect of computed tomography–guided bilateral pudendal nerve cryoablations on pain and time to discharge in the setting of acute hospitalizations secondary to refractory pelvic pain from cancer. Methods: Investigators queried the medical record for patients who underwent pudendal nerve cryoablation using the Category III Current Procedural Technology code assignment 0442T or Category I code 64640 for cases prior to 2015. The resulting list was reviewed, and procedures performed on inpatients for intractable pelvic pain related to neoplasm were selected. The final cohort was then analyzed with regard to patient demographics, procedure details, technical success, safety, pain scores, and time to discharge. Results: Ten patients underwent cryoablation by 3 operators for palliation of painful pelvic neoplasms between June 2014 and January 2019. All probes were satisfactorily positioned and freeze cycles undertaken without difficulty. There were no procedure-related complications or adverse events. The mean difference in pre- and posttreatment worst pain scores was significant (n = 5.20, P = .003). The mean time to discharge following the procedure was 2.3 days. Conclusion: Computed tomography–guided percutaneous cryoablation of the bilateral pudendal nerves may represent a viable option in the setting of acute hospitalization secondary to intractable pain in patients with pelvic neoplasms.

Dorsal Root Ganglion Stimulation Therapy for Refractory Idiopathic Pudendal Neuralgia

“…It found rough equivalency in pain relief out to 30 days but improved symptoms with pulsed radiofrequency therapy extending from one to three months [16,17]. Analogous to radiofrequency ablation, cryotherapy of the pudendal nerve is also a promising modality, based on a recent case series, which reported an average reduction in pain of 60% for up to six months after the procedure [18]. However, there is lack of any larger prospective trials evaluating the long-term safety and efficacy of cryotherapy.…”

Cryoanalgesia: Review with Respect to Peripheral Nerve

“…Two structured studies are found in the literature, both prospective reviews of structured clinical practices. 8,9 The first paper describes eleven patients treated percutaneously with CT guidance who presented with symptoms of pudendal neuralgia and underwent CT guided diagnostic block for confirmation (Figure 3). All patients were administered the Brief Pain Inventory as part of their clinical follow up and records existed for clinic visits to a mean of 204 days post procedure.…”

“…42 Various sources of pain can arise related to pudendal nerve damage or transmitted via the pudendal nerves. 8,9,11 Operators may safely target cryoanalgesia of the pudendal nerve with existing equipment either at bedside using imaging guidance, or intraoperatively. (Figure 3) When the temperature is lowered throughout the nerve to -20° C or below (but not colder than -100° Celsius), signal transduction is interrupted and Wallerian degeneration is induced, followed by predictable axonal regeneration over a period of 6-8 months.…”

“…as defined by a ≥ 50% improvement in pain, were 67% and 81% respectively in the studies described above. 8,9 The finding of a transient increase in intercostal neuropathic pain may be better understood based upon previous clinical and basic science investigations of cryotherapy. Notably, the observed temporary period of increased pain several weeks after treatment followed by reduction and resolution by 6 months follows a similar timeline to that demonstrated after targeted muscle reinnervation (TMR) in which sensory and/or mixed nerves are transferred or co-apted to motor nerve branches, to promote organized nerve growth and also to improve prosthetic control 46,47 .…”

Interventional Radiology Obesity Therapeutics: Proceedings from the Society of Interventional Radiology Foundation Research Consensus Panel

“…The mechanisms underpinning appetite and weight control following vagotomy are complex. They involve the interruption of mostly afferent fibers (80%-90%) carrying signals from the gut to the brain, resulting in appetite suppression, weight reduction, and weight loss maintenance (68)(69)(70). A single pilot study (67) has evaluated the safety and efficacy of computed tomographyguided percutaneous cryovagotomy in patients who are overweight or have obesity.…”