B Berman, AQ Shabbir, T MacNeil, KM Knudsen.
Variables in Cryosurgery Technique Associated With Clearance of Actinic Keratosis
Dermatol Surg 2017 Mar 01;43(3)424-430.
Cryosurgery is the most commonly used method to treat actinic keratosis (AK). Cryosurgical methods are not standardized.
To examine differences in the spray techniques used for liquid nitrogen cryosurgery when treating AKs of the head, and the effect of these variations in technique on rates of complete clearance of AKs.
MATERIALS AND METHODS
Patients were those from the FIELD-1 study, who received cryosurgery as per the investigators' usual practice to all AKs. This was followed by topical treatment with either vehicle gel or ingenol mebutate gel, 0.015%, after 3 weeks. The investigator recorded the average duration of cryosurgery spray used, the number of freeze-thaw cycles, and the distance from the tip of the spray device to the AK. Clearance rates were determined at Week 11.
Less-aggressive freezing techniques were used for AKs on the face than for those on the scalp. However, higher rates of complete clearance on the face and scalp were associated with more-aggressive freezing techniques.
Patients with AKs on the face receive less-aggressive cryosurgery than do patients with AKs on the scalp.