Cryoanalgesia - a minimally invasive method of pain relief
Cryoanalgesia, or treatment by means of cold, is a special method to provide long-term pain relief. Cryoanalgesia temporarily interrupts functioning of neurons and motor nerves in the nervous system, using cold. Cryoanalgesia is getting more and more popular method of relieving pain. The analgesia is based on cold-induced ice crystals, which destroy the nerve cells that carry information about the pain. The procedure does not completely destroy the nerve structure, so the nerve tissue can regenerate. The method is safe and minimally invasive. It is recommended in cases where conservative treatment has proved ineffective.
Cryoanalgesia is mostly used for lumbar, hip and knee pain. Less often it is also used in the facial nerves, upper extremities, chest, abdomen and pelvis pain.
The procedure of cryoanalgesia and benefits of it
The cryoanalgesia procedure is being performed locally in the site affected by pain under local anesthesia (injection). During the procedure, a small incision is made, to introduce a cryosond consisting of a hollow tube with a smaller inner tube inside and the gas cooled to -89 ° C is supplied.
As soon as the patient feels the stimulation in the point of maximum pain, the stimulation is reduced and the nerve is frozen. 2-3 minute long freezing series are performed, with 30s defrost intervals before each cycle. Burning pain usually occurs at the beginning of the first freeze cycle, which may be recurring, but resolves in about 30 seconds. The rest of the procedure is completely painless.
Advantages of the cryoanalgesia:
- minimally invasive, relatively painless procedure;
- highly efficacious – pain relief for 6 months to 1 year;
- subcutaneous procedure under local anesthesia;
- quick return to daily activities;
- no hospitalization required;
- repeated procedures possible
Historical facts about the use of cold in medicine
The use of cold for analgesia or pain relief has been known to mankind for millennia.
Hippocrates (460-377 AD) provided the first written evidence of the use of ice to relieve pain, describing how snow was taken from the mountains to be used to relieve wound pain in ancient Greece.
The ancient Persian physician Avicenna (980-1070 BC) described the use of cold for preoperative analgesia.
A Scottish surgeon, scientist John Hunter, noted in 1777 that when the cells of a rooster’s crest were destroyed by cold, the base of the crest had healed without scarring.
In 1812, Jean Larrey, Napoleon’s chief physician, noticed that half-frozen soldiers in the Battle of Borodino could undergo amputation of their limbs with little or no pain.
The dawn of modern cryoanalgesia can be traced back to 1961, when they developed a device that used liquid nitrogen in a hollow tube, the end of which was insulated and was able to reach as low temperature as – 190 ° C.
Selig Percy Amoyle, ophthalmologist and biomedical engineer-inventor from South Africa, developed a simpler handheld device in 1967, that used carbon dioxide or nitrous oxide and could reach temperatures of -70ºC.