Cryoanalgesia. Ultrastructural Study on Cryolytic Lesion of Sciatic Nerve in Rat and Rabbit

Evaluation of Intercostal Cryoanalgesia versus Conventional Analgesia in Postthoracotomy Pain

“…Postoperative pain in the first hours is not due to the tho racotomy but to the position of the patient during surgery', to the surgical technique and to the fact that cryoanalgesia does not act on the rachis nerve so that there are some sensitive Tranches which are not involved in cryoanalge sia. Therefore the association of transcutaneal stimulation in the posterior area of the scar has been reported [ 17], These findings are consistent with the wallerian degen eration and further regeneration at a rate of 1 mm per day as has been reported following cryoanalgesia [ 14,[18][19][20].…”

Sonographically Guided Cryoneurolysis

“…The cryotherapy machine used was a Frigitronics CE 2000 (Cooper Surgical, Inc, Trumbull, CT). The coolant used was nitrous oxide, although carbon dioxide can be substituted with the same effects 4 . Argon as a coolant has been shown to have advantages in tumor and cardiac applications, including faster freeze and thaw cycles, faster halting of the freeze cycle, colder temperatures, and smaller probe sizes 3 , 12 ; however, its use has not yet been documented for peripheral cryoneurolysis.…”

“…At temperatures below −20°C, intracellular ice forms, the major mechanism for cell injury in cryoneurolysis 3 . In an animal model, controlled cryoinjury to nerves resulted in total degeneration of the myelin fibers, whereas nonmyelin fibers and vessels were less affected 4 . Regeneration follows the injury, as the Schwann cell basal lamina is spared and provides the structure for regeneration 5 .…”

“…When the endoneurium is spared, neuroma formation does not occur 6 . Early regeneration begins 2 weeks after freezing, with the time to total regeneration related to the rate of axonal regrowth and the distance of the cryo‐produced lesion from the end organ 4 . Given these circumstances, it is postulated that cryotherapy will have less adverse events than other methods of nerve ablation.…”

Ultrasound Assessment of Ice-Ball Formation by Cryoneurolysis Device in an Ex Vivo Model

“…2 The mechanism of axonotmesis has been well documented, and it is presently known that pain alleviation is obtained through second-degree nerve injury, leading to reversible axon degeneration when temperatures below −20°C are used. 3,4 Compared with neurolysis techniques (alcohol or radiofrequency), cryoneurolysis has the advantage of avoiding neuroma formation or marked neuritis following nerve injury. 5 Indications of cryoneurolysis in chronic pain management are numerous 2 and include peripheral neuropathic syndromes (trigeminal neuralgia, 6 neuromas, 7 intercostal neuralgia, 8,9 or occipital neuralgia 10 ), facet joint syndrome, 11 or phantom limb syndrome.…”