title: Variables in Cryosurgery Technique Associated With Clearance of Actinic Keratosis.
abstract: BACKGROUND
  Cryosurgery is the most commonly used method to treat actinic keratosis (AK). Cryosurgical methods are not standardized.
  
  
  OBJECTIVE
  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.
  
  
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  Patients with AKs on the face receive less-aggressive cryosurgery than do patients with AKs on the scalp.
authors.affiliation: *University of Miami Miller School of Medicine, Miami, Florida; †Center for Clinical and Cosmetic Research, Aventura, Florida; ‡p-value communications, Cedar Knolls, New Jersey; §LEO A/S, Copenhagen, Denmark.
authors.forename: Brian
authors.initials: B
authors.lastname: Berman
authors.forename: Arsalan Qazi
authors.initials: AQ
authors.lastname: Shabbir
authors.forename: Tanya
authors.initials: T
authors.lastname: MacNeil
authors.forename: Kim Mark
authors.initials: KM
authors.lastname: Knudsen
mesh_terms: D000279:Administration, Cutaneous; D000293:Adolescent; D000328:Adult; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods; D003879:Dermatologic Agents / Q000008:administration & dosage*; D004224:Diterpenes / Q000008:administration & dosage*; D005145:Face / Q000601:surgery; D005782:Gels / Q000008:administration & dosage; D006801:Humans; D055623:Keratosis, Actinic / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery*; D012307:Risk Factors; D012535:Scalp / Q000601:surgery; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014481:United States
chemical_list: D003879:Dermatologic Agents; D004224:Diterpenes; D005782:Gels; C008125:ingenol