January 20, 2011 Doctor Lawrence Jaeger treats patients in need of Cryotherapy for skin disorders at Advanced Dermatology Associates in New York City. Cryosurgery is used frequently by dermatologist to treat many skin problems. Liquid nitrogen is sprayed on to the area of skin freezing it. Light freezing causes a peeling, moderate freezing a blistering and hard freezing a scabbing. The most common uses for cryosurgery is to treat warts, seborrheic keratoses and actinic keratoses. It is also used for acne, scars, small benign growths and some skin cancers. Older dermatologists still use a swab to apply it, but the result is the same. Specialist dermatologists sometimes freeze small skin cancers such as superficial basal cell and in situ squamous cell carcinomas (Bowen’s disease), but this is not always successful so careful follow-up is necessary. Freezing may be the most suitable way of getting rid of many different kinds of surface skin lesion. It is relatively inexpensive, safe, and reliable. However, it is important that the skin lesion has been properly diagnosed. It should not be used to treat melanoma or any undiagnosed pigmented lesion that could be melanoma. The treatment Liquid nitrogen Cryotherapy using liquid nitrogen (temperature –196C) involves the use of a cryospray, cryoprobe or a cotton-tipped applicator. The nitrogen is applied to the skin lesion for a few seconds, depending on the desired diameter and depth of freeze. The treatment is repeated in some cases, once thawing has completed. This is known as a ‘double freeze-thaw’ and is usually reserved for skin cancers or resistant viral warts. Carbon dioxide snow Carbon dioxide cryotherapy involves making a cylinder of frozen carbon dioxide snow (–78.5C) or a slush combined with acetone. It is applied directly to the skin lesion. DMEP DMEP works at a temperature of –57C. It comes in an aerosol can available over the counter. It is used to treat warts using a foam applicator pushed onto the skin lesion for between 10 and 40 seconds, depending on its size and site. Cryotherapy stings and may be painful, at the time and for a variable period afterwards. There may be immediate swelling and redness. This may be reduced by applying a topical steroid on a single occasion straight after freezing. Aspirin orally may also reduce the inflammation and discomfort.