WM has received grants from EDDA Technologies (Princeton, New Jersey) and Endo Pharmaceuticals (Malvern, Pennsylvania) outside the present work and has a patent pending for Scannerside (Setauket, New York). None of the other authors have identified a conflict of interest. Cryoneurolysis in Patients with Refractory Chronic Peripheral Neuropathic Pain

Purpose: To evaluate the safety and efficacy of cryoneurolysis in patients with refractory peripheral neuropathic pain. Materials and Methods: Twenty-two patients referred for cryoneurolysis of refractory peripheral neuropathy were recruited prospectively from July 2011 to July 2013. The mean patient age was 49.5 years, and 41% of patients were female. Ultrasound imaging of the involved nerves was used for guidance. Percutaneous ablations were performed with a PerCryo 17R device. Pain levels were recorded on a visual analog scale (scores 0-10) before and at 1, 3, 6, 9, and 12 months after the procedure, and complications were documented. Results: Mean pain levels were 8.3 +/- 1.9 before intervention and 2.3 +/- 2.5 at 1 month, 3.2 +/- 2.5 at 3 months, 4.7 +/- 2.7 at 6 months, and 5.1 +/- 3.7 at 12 months afterward. A Wilcoxon rank-sum test was performed and showed a statically significant decrease between pre- and postprocedural pain scores. There were no complications from the procedures. Discussion: Cryoneurolysis caused a significant decrease in self-reported pain scores in patients with chronic refractory neuropathic pain, with moderately long-term relief. Cryoneurolysis is an additional therapy that can alleviate severe chronic neuropathic pain.