A Review of Nonsurgical Neurolytic Procedures for Neuropathic Pain

Ideally, a physical or chemical nonsurgical neurolytic procedure provides targeted neurolysis to relieve pain for a suitable length of time without causing complications. This narrative review focuses on five nonsurgical neurolytic procedures that are well-established and well-documented in the literature for the treatment of refractory neuropathic pain and peripheral neuropathies, in particular: two physical nonsurgical neurolytic techniques (cryoablation and radiofrequency ablation) and three chemoneurolytic agents (alcohol injection, phenol injection, and a high-concentration capsaicin 8% topical system).

Using the definition of nonsurgical physical and chemical neurolytic procedures for neuropathic pain, a focused literature search of the PubMed database for English-language, human studies published through July 2024 included, but was not limited to, the following search terms: "neuropathic pain" AND "cryoablation", "cryoneurolysis", "radiofrequency ablation", "alcohol neurolysis", "alcohol injection", "phenol neurolysis", "phenol injection", "chemoneurolysis", "topical capsaicin", and "TRPV1." While attempts were made to identify prospective clinical trials for each type of neurolytic procedure, information regarding the conduct and safety and efficacy of some of these nonsurgical neurolytic procedures was primarily limited to case studies and anecdotal evidence.

The risk benefit basis of each technique is discussed, and recommendations for proper use based on the literature are summarized. Most techniques require ultrasound or fluoroscopy guidance. Pain relief typically ranges from 3 to 12 months, with repeat neurolytic procedures often required to maintain suitable levels of pain relief.

The authors provide their insights as to the best utilization of these identified nonsurgical physical and chemoneurolytic procedures for the treatment of refractory neuropathic pain in different patient populations based on neural targets. Together, these five nonsurgical neurolytic techniques provide patients and physicians with a variety of options for the treatment of refractory neuropathic pain.