title: Intralesional Cryotherapy for the Treatment of Keloid Scars: Evaluating Effectiveness.
abstract: BACKGROUND
  Intralesional (IL) cryotherapy is a novel treatment technique for keloid scars, in which the scar is frozen from inside. Over the past decade, several studies have been published with varying outcomes. A critical analysis of the current literature is, therefore, warranted to determine whether IL cryotherapy is an alternative to established keloid scar treatments.
  
  
  METHODS
  A comprehensive review was performed, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. PubMed and EMBASE were searched from inception. Studies and level of recommendation were graded according to the American Society of Plastic Surgeons criteria.
  
  
  RESULTS
  Eight studies meeting the inclusion criteria were selected. The average scar volume decrease ranged from 51% to 63%, but no complete scar eradication was achieved on average. Scar recurrence ranged from 0% to 24%. Hypopigmentation posttreatment was seen mostly in Fitzpatrick 4-6 skin type patients. Finally, complaints of pain and pruritus decreased significantly in most studies.
  
  
  CONCLUSIONS
  IL cryotherapy for the treatment of keloid scars shows favorable results in terms of volume reduction and alleviated complaints of pain and pruritus. However, no complete scar eradication is established, and recurrences are seen. Also, persistent hypopigmentation proved a problem in Fitzpatrick 4-6 skin type patients. Summarized, the evidence proved limited and inconsistent resulting in an American Society of Plastic Surgeons grade C recommendation for this type of treatment of keloid scars.
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands; Medical Library, VU University, Amsterdam, The Netherlands; and Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Michiel C E
authors.initials: MC
authors.lastname: van Leeuwen
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands; Medical Library, VU University, Amsterdam, The Netherlands; and Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Anne Eva J
authors.initials: AE
authors.lastname: Bulstra
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands; Medical Library, VU University, Amsterdam, The Netherlands; and Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Johannes C F
authors.initials: JC
authors.lastname: Ket
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands; Medical Library, VU University, Amsterdam, The Netherlands; and Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Marco J P F
authors.initials: MJ
authors.lastname: Ritt
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands; Medical Library, VU University, Amsterdam, The Netherlands; and Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Paul A M
authors.initials: PA
authors.lastname: van Leeuwen
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands; Medical Library, VU University, Amsterdam, The Netherlands; and Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Frank B
authors.initials: FB
authors.lastname: Niessen