No preparation is required usually. With a probe, spray, or swab, an icy substance most commonly liquid nitrogen is applied to a small area that create these freezing temperatures. When applied directly to the skin, the sudden and intense cold creates formations of ice crystals inside the skin cells, killing the undesired cells on contact. The whole procedure takes a few minutes at most. Cryo means “ice cold” in Greek, and the patient can expect to feel the cold, but little pain. Depending on the case, there may be one round of cryotherapy, or several.