Cryosurgery << KRY oh SUR juhr ee >> is a medical technique for destroying abnormal or diseased tissue through the use of cold. Cryosurgery is only appropriate for use against localized disease —that is, disease limited to a part of the body. Medical professionals commonly use cryosurgery to treat skin conditions such as warts , skin tags, moles , early stage skin cancers , and precancerous growths. Cryosurgery can also be used to treat conditions inside the body. These include liver and prostate cancers , cervical disorders, bone tumors , soft-tissue tumors, and a painful foot condition called plantar fasciitis .
Doctors freeze tissue using substances called cryogens that can reach very low temperatures. Common cryogens include liquid nitrogen , carbon dioxide , argon , nitrous oxide, and dimethyl ether-propane. Cryosurgery damages the target tissue in many ways. During the freezing process, ice crystals form in and around the cells , puncturing the cellular membranes and internal structures. During freezing, water leaves the cells, causing them to dehydrate. The expansion and contraction of water during freezing and thawing can also cause cracks to form within the cells. Slow thawing and repeated cycles of freezing and thawing increase the damage to the tissue. Such treatment may also damage blood supply to the abnormal tissue, preventing regrowth.
Doctors can use several methods to conduct cryosurgery. For small skin conditions, doctors may apply liquid cryogen directly to the skin with an applicator. For more extensive conditions, doctors use a special device to spray cryogen on the affected area. A cryoprobe may be used to treat external or internal conditions. A cryoprobe is a needlelike device with cryogen circulating through it. Doctors make one or more small incisions so the cryoprobe can reach the target tissue in internal cryosurgery.
During cryosurgery, doctors must protect the surrounding skin and tissue from the extreme cold. For procedures conducted on the surface of the body, such as mole removal, doctors use a protective cone that restricts contact with the cryogen to the area being treated. The doctor applies cryogen directly to the skin with an applicator. After the cone has been removed, a frozen white lesion known as an iceball may be seen in the treatment area. A scab then forms over the treated area. The scab falls off once the skin has healed. In the case of internal cryosurgery, the frozen tissue thaws and is naturally absorbed by the body.
Cryosurgery has advantages over other, more invasive surgical techniques. These advantages include shorter recovery times, minimal pain and scarring, fewer side effects, and lower cost. However, there are risks and side effects associated with cryosurgery. They include redness, swelling, localized pain, changes in skin pigmentation, hair loss in the treated area, and damage to nearby healthy tissue and nerves.
