CRYOABLATION
TECHNOLOGY
History of Cryotherapy
The term cryotherapy
comes from the prefix cryo (from the Greek word
"kruos" for cold) and the word therapy meaning
cure. Applying cold energy to human tissues is
a well-known technique for treating various lesions.
The controlled destruction of tissue
by freezing is today widely practiced for various
clinical applications. Terms for it include cryotherapy,
cryosurgery, and more recently, the term cryoablation
has been coined, due to the growing popularity
of ablation technologies as minimally invasive
procedure alternatives to surgery.
Over the last 200 years, cold treatment
has evolved from a general application to the
focal destruction of target tissue, represented
by today’s cryotherapy ablation treatments used
for prostate
cancer, kidney
tumors, liver
tumors, lung cancer, and bone tumors.
As early as in 2500 B.C., low temperatures were used in Egypt to treat injuries and inflammation. The Greek physician Hippocrates (460-370 B.C.) recommended placing ice or snow on injured parts of the body to stop bleeding and swelling. Dominique-Jean Larrey, Napoleon's surgeon, used it to facilitate amputations during the historic retreat from Moscow.
The benefits of cryosurgery were first used in London in the mid 1850s. The first modern physician to utilize the cryotherapy (freezing) technique was Dr. James Arnott of Brighton, England. He described the benefits of the application of cold for the cryosurgical treatment of numerous conditions.
Arnott observed the shrinking of tumors and pain relief after using salt solutions containing crushed ice to freeze breast, cervical, and skin cancers. Arnott also recognized the numbing effects of cold, recommending the use of cold as an anesthetic before surgery.
The salt and ice solutions were not able to reduce tissue temperatures sufficiently for effective tumor ablation treatment. It was not until refrigerants came into use that lower tissue temperatures could be achieved for cryosurgical ablation. In the late 1800s to early 1900s, researchers experimented with liquefied gases including liquid air, oxygen and carbon dioxide applied to skin tissue with cotton swabs and sprays to treat carcinoma of the skin.
The gases were stored in cylinders under
pressure. When the gas was released, rapid expansion
caused a dramatic drop in temperature (the Joule-Thomson
effect). These techniques were mostly used for
the treatment of a large range of skin conditions.
The debate over which gas provided the best cryogen
continued during the first half of the twentieth
century.
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