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cryotherapy
cry·o·ther·a·py C0781800 (krī′ō-thĕr′ə-pē)n. The local or general use of low temperatures in medical therapy. Also called crymotherapy.cryotherapy (ˌkraɪəʊˈθɛrəpɪ) or crymotherapyn (Medicine) medical treatment in which all or part of the body is subjected to cold temperatures, as by means of ice packscry•o•ther•a•py (ˌkraɪ oʊˈθɛr ə pi)
n. medical treatment by means of applications of cold. [1925–30] cryotherapya method of treatment involving applications of cold. Also crymotherapy.See also: RemediesTranslationsCryotherapy
cryotherapy[¦krī·ō′ther·ə‚pē] (medicine) A form of therapy which consists of local or general use of cold. Cryotherapy the therapeutic use of cold. Since ancient times ice packs and sheets soaked in water have been used in treating disease. Moderate cooling (without causing freezing) is used to reduce inflammatory phenomena, stop bleeding, relieve pain, and decrease swelling. The effect of cold is explained by reflex reaction (the constriction of blood vessels and the slowing of blood flow) or by lowering of the metabolism in the given region. Cold (the application of ice bags) is used for a variety of inflammations (in the region of the gall-bladder, appendix, stomach, pancreas), bruises, and fractures. Application of ice bags to the affected area or swallowing pieces of ice is prescribed for pulmonary, nasal, and gastrointestinal bleeding. Dressings with chilled alcohol are applied to burns. Specially designed rubber helmets through which cold water constantly flows are worn to control edema by individuals suffering from brain concussions or contusions. In the case of short operations (for example, the lancing of abscesses or phlegmons), anesthesia is achieved by spraying the tissues with ethyl chloride, removing the heat, freezing them, and lowering their sensitivity. Cooling the body generally, or hypothermia, is used in operations on the heart, major blood vessels, and brain. V. A. DUMCHEV One of the most important branches of cryotherapy is cryosurgery, a new field that uses low temperatures to destroy organs and tissues. Attempts to use cold to destroy tissues were first made in the 1940’s, when the American surgeon T. Fay subjected malignant tumors in inoperable patients to prolonged chilling and obtained noticeable, although brief, remissions. Many dermatologists use local freezing (mostly with carbon dioxide) for certain diseases and malignancies of the skin. It has proved to be much more difficult to freeze tissues locally deep within the body. Chilling mammalian tissues to the freezing point results in their total and irreversible necrosis. This is a consequence of the dehydration of the cells implied in the formation of ice crystals (both within the cells and in the extracellular fluid), the sharp increase in the concentration of electrolytes within the cells (”osmotic shock”), the mechanical injury to the cellular membranes and organelles by the ice crystals, and the cessation of the blood flow in the region frozen. The local refrigeration of deep structures in the human body became possible with the creation of suitable apparatus. As a result, cryosurgery has been introduced into various medical fields. Tests with Freon and other refrigerants have shown that liquid nitrogen (boiling point, −195.8°C) is the most suitable for cryosurgical purposes. Cryosurgery is widely used in brain operations. It was used for the first time in 1961 in the USA in stereotaxic operations in order to create a strictly local focus of destruction (7–9 mm) in the deep subcortical structures of the brain. In 1962, the Soviet scientists A. I. Shal’nikov and E. I. Kandel’ constructed an original instrument for the cryogenic destruction of deep structures in the brain. Its principal element consists of a thin metal tube, or cannula, with a reservoir of liquid nitrogen. The tip of the cannula, stereotaxically guided to the appropriate structure, produces a temperature sufficiently low to turn the prescribed area of brain tissue to ice. Since the thin cold-conductor inside the cannula is insulated against heat by a deep vacuum (10−7 mm Hg), the cannula itself remains warm; a temperature of −70° is created only at the tip (2 mm long). A ball of ice, 5–9 mm in diameter, forms in its vicinity only. The nitrogen is then boiled away and the ball thaws; the frozen brain tissue, thawing in turn, then dies. Another model of this instrument, developed in 1970, is capable of freezing a substantial amount of tumor tissue (as much as 50–55 mm in diameter). Cryosurgery is used in stereotaxic operations on the brain for parkinsonism, torsion dystonia, athetosis, spastic torticollis, and severe pain. Cryodestruction of the normal pituitary is effective against metastases of certain types of cancer. The freezing of pituitary tumors is a promising procedure for acromegaly and Itsenko-Cushing syndrome. Promising results have been obtained in the cryodestruction of tumors of the cerebral hemispheres. Cryosurgery is also used in the treatment of certain eye diseases (retinal detachment, intraocular tumors) and to remove tonsils, nasopharyngeal polyps, tumors of the nose, and prostatic adenomas. E. I. KANDEL’ cryotherapy
Cryotherapy DefinitionCryotherapy is a technique that uses an extremely cold liquid or instrument to freeze and destroy abnormal skin cells that require removal. The technique has been in use since the turn of the century, but modern techniques have made it widely available to dermatologists and primary care doctors. The technique is also called cryosurgery.PurposeCryotherapy can be employed to destroy a variety of benign skin growths, such as warts, pre-cancerous lesions (such as actinic keratoses), and malignant lesions (such as basal cell and squamous cell cancers). The goal of cryotherapy is to freeze and destroy targeted skin growths while preserving the surrounding skin from injury.PrecautionsCryotherapy is not recommended for certain areas of the body because of the danger of destruction of tissue or unacceptable scarring. These areas include: skin that overlies nerves, the corners of the eyes, the fold of skin between the nose and lip, the skin surrounding the nostrils, and the border between the lips and the rest of the face. Lesions that are suspected or known to be malignant melanoma should not be treated with cryotherapy, but should instead be removed surgically. Similarly, basal cell or squamous cell carcinomas that have reappeared at the site of a previously treated tumor should also be removed surgically. If it remains unclear whether a growth is benign or malignant, a sample of tissue should be removed for analysis (biopsy) by a pathologist before any attempts to destroy the lesion with cryotherapy. Care should be taken in people with diabetes or certain circulation problems when cryotherapy is considered for growths located on their lower legs, ankles, and feet. In these patients, healing can be poor and the risk of infection can be higher than for other patients.DescriptionThere are three main techniques to performing cryotherapy. In the simplest technique, usually reserved for warts and other benign skin growths, the physician will dip a cotton swab or other applicator into a cup containing a "cryogen," such as liquid nitrogen, and apply it directly to the skin growth to freeze it. At a temperature of −320°F (−196°C), liquid nitrogen is the coldest cryogen available. The goal is to freeze the skin growth as quickly as possible, and then let it thaw slowly to cause maximum destruction of the skin cells. A second application may be necessary depending on the size of the growth. In another cryotherapy technique, a device is used to direct a small spray of liquid nitrogen or other cryogen directly onto the skin growth. Freezing may last from five to 20 seconds, depending on the size of the lesion. A second freeze-thaw cycle may be required. Sometimes, the physician will insert a small needle connected to a thermometer into the lesion to make certain the lesion is cooled to a low enough temperature to guarantee maximum destruction. In a third option, liquid nitrogen or another cryogen is circulated through a probe to cool it to low temperatures. The probe is then brought into direct contact with the skin lesion to freeze it. The freeze time can take two to three times longer than with the spray technique.PreparationExtensive preparation prior to cryotherapy is not required. The area to be treated should be clean and dry, but sterile preparation is not necessary. Patients should know that they will experience some pain at the time of the freezing, but local anesthesia is usually not required. The physician may want to reduce the size of certain growths, such as warts, prior to the cryotherapy procedure, and may have patients apply salicylic acid preparations to the growth over several weeks. Sometimes, the physician will pare away some of the tissue using a device called a curette or a scalpel.AftercareRedness, swelling, and the formation of a blister at the site of cryotherapy are all expected results of the treatment. A gauze dressing is applied and patients should wash the site three or four times daily while fluid continues to ooze from the wound, usually for five to 14 days. A dry crust then forms that falls off by itself. Wounds on the head and neck may take four to six weeks to heal, but those on the body, arms, and legs can take longer. Some patients experience pain at the site following the treatment. This can usually be eased with acetaminophen (Tylenol), though in some cases a stronger pain reliever may be required.RisksCryotherapy poses little risk and can be well-tolerated by elderly and other patients who are not good candidates for other surgical procedures. As with other surgical procedures, there is some risk of scarring, infection, and damage to underlying skin and tissue. These risks are generally minimal in the hands of experienced users of cryotherapy.Key termsActinic keratosis — A crusty, scaly pre-cancerous skin lesion caused by damage from the sun. Frequently treated with cryotherapy.Basal cell cancer — The most common form of skin cancer; it usually appears as one or several nodules having a central depression. It rarely spreads (metastisizes), but is locally invasive.Cryogen — A substance with a very low boiling point, such as liquid nitrogen, used in cryotherapy treatment.Melanoma — The most dangerous form of skin cancer. It should not be treated with cryotherapy, but should be removed surgically instead.Squamous cell cancer — A form of skin cancer that usually originates in sun-damaged areas or pre-existing lesions; at first local and superficial, it may later spread to other areas of the body.Normal resultsSome redness, swelling, blistering and oozing of fluid are all common results of cryotherapy. Healing time can vary by the site treated and the cryotherapy technique used. When cryogen is applied directly to the growth, healing may occur in three weeks. Growths treated on the head and neck with the spray technique may take four to six weeks to heal; growths treated on other areas of the body may take considerably longer. Cryotherapy boasts high success rates in permanently removing skin growths; even for malignant lesions such as squamous cell and basal cell cancers, studies have shown a cure rate of up to 98%. For certain types of growths, such as some forms of warts, repeat treatments over several weeks are necessary to prevent the growth's return.Abnormal resultsAlthough cryotherapy is a relatively low risk procedure, some side effects may occur as a result of the treatment. They include:- Infection. Though uncommon, infection is more likely on the lower legs where healing can take several months.
- Pigmentary changes. Both hypopigmentation (lightening of the skin) and hyperpigmentation (darkening of the skin) are possible after cryotherapy. Both generally last a few months, but can be longer lasting.
- Nerve damage. Though rare, damage to nerves is possible, particularly in areas where they lie closer to the surface of the skin, such as the fingers, the wrist, and the area behind the ear. Reports suggest this will disappear within several months.
ResourcesOrganizationsAmerican Academy of Dermatology. 930 N. Meacham Road, P.O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. Fax: (847) 330-0050. http://www.aad.org.American Society for Dermatologic Surgery. 930 N. Meacham Road, PO Box 4014, Schaumburg, IL 60168-4014. (847) 330-9830. http://www.asds-net.org.cryotherapy [kri″o-ther´ah-pe] the therapeutic use of cold; see also hypothermia.cry·o·ther·a·py (krī'ō-thār'ă-pē), The use of cold in the treatment of disease.cryotherapy (krī′ō-thĕr′ə-pē)n. The local or general use of low temperatures in medical therapy. Also called crymotherapy.cold therapy A general term for the use of ice or cold compresses for therapeutic purposes; locally applied ice increases the circulation and relieves pain, and is of use in acute trauma. Practitioners of alternative therapies may advocate alternating ice and heat, as it is believed to “flush” a region with fresh blood.cryotherapy Mainstream medicine The use of cold to ↓ discomfort, limit progression of edema or interrupt muscle spasms, which acts as a counterirritant Ophthalmology A safe, effective therapy for retinopathy of prematurity Cons ↓ visual acuity and smaller visual fieldcold ther·a·py (kōld thār'ă-pē) A type of care in which ice or cold water is applied to a body part.
Synonym(s): cryotherapy. cryotherapy (krī″ō-ther′ă-pē) [ cryo- + therapy]  CRYOTHERAPY: Frosting of the skin at the site of actinic keratosis after treatment with liquid nitrogen1. The application of cold to a body part to decrease tissue temperature, and thereby to decrease cellular metabolism, improve cellular survival, decrease inflammation, decrease pain and muscle spasm, and promote vasoconstriction. See: illustrationtable 2. Cryosurgery.| Indications | Contraindications |
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| Acute injury or inflammation | Anesthetic skin | | Acute or chronic pain | Cold allergy/cold-induced urticaria | | Acute or chronic muscle spasm | Cold-induced myocardial ischemia (or other unstable heart or lung disease) | | Neuralgia | Diabetes mellitus (when complicated by vascular disease or sensory loss) | | Postsurgical pain and edema | Peripheral vascular disease | | Use prior to rehabilitation exercises | Raynaud's phenomenon | | Small, superficial, first-degree burns | Systemic lupus erythematosus | | Spasticity accompanying central nervous system disorders | Uncovered open wounds | SOURCE: Adapted from Starkey, C: Therapeutic Modalities, ed 3., F. A. Davis Co., Philadelphia, 2004.
cryotherapy The use of low temperatures in medical treatment. Temperatures of about -20 C or below are useful in surgery, especially for destroying unwanted tissue such as warts, ACTINIC KERATOSIS and skin nodules (dermatofibromas). See also CRYOSURGERY.cryotherapy Method of treating a disease by the use of cold as a destructive medium. It may be used in the treatment of retinal detachment and breaks, conjunctival melanomas, lid tumours, uveitis, distichiasis and trichiasis. |