Cryosurgery involves using liquid nitrogen to freeze tissue with the intention of removing growths such as warts, skin tags, and precancerous lesions. Liquid nitrogen is sprayed onto skin lesions causing a white color change; this is the ice ball stage. Ice crystals are forming inside cells causing destruction of tissue. An inflammatory reaction develops within 30 minutes.
Immediately after freezing, the skin will appear red and swollen. There will be a temporary sensation of throbbing and stinging that subsides after about 30 minutes. Blisters may form. The skin will crust and scab over the next several days. Facial skin heals in about 7-10 days, other areas of the body take longer to heal. Arms and hands can take 2-2 1/2 weeks to heal (for scabs to completely slough off). Legs can take 4-6 weeks to heal.
Petrolatum or Aquaphor healing ointment should be applied 4-5 times a day to the treated areas. The skin is gently washed with soap and water using your hands and gently patted dry. Avoid rubbing, picking, scratching as this can delay healing and increase risk of infection. A nonstick dressing such as Telfa can be applied if the areas treated are rubbing on clothing. Keep the healing skin out of the sun.