title: Paradoxical adipose hyperplasia after cryolipolysis.
abstract: OBJECTIVE
  Cryolipolysis is the noninvasive reduction of fat with localized cutaneous cooling. Since initial introduction, over 650,000 cryolipolysis treatment cycles have been performed worldwide. We present a previously unreported, rare adverse effect following cryolipolysis: paradoxical adipose hyperplasia.
  
  
  METHODS
  A man in his 40s underwent a single cycle of cryolipolysis to his abdomen. Three months following his treatment, a gradual enlargement of the treatment area was noted. This enlargement was a large, well-demarcated subcutaneous mass, slightly tender to palpation. Imaging studies revealed accumulation of adipose tissue with normal signal intensity within the treatment area.
  
  
  CONCLUSIONS
  Paradoxical adipose hyperplasia is a rare, previously unreported adverse effect of cryolipolysis with an incidence of 0.0051%. No single unifying risk factor has been identified. The phenomenon seems to be more common in male patients undergoing cryolipolysis. At this time, there is no evidence of spontaneous resolution. Further studies are needed to characterize the pathogenesis and histologic findings of this rare adverse event.
authors.affiliation: Division of Dermatology, University of California, Los Angeles, Los Angeles2Wellman Center for Photomedicine, Massachusetts General Hospital, Boston.
authors.forename: H Ray
authors.initials: HR
authors.lastname: Jalian
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston3Department of Dermatology, Massachusetts General Hospital, Boston.
authors.forename: Mathew M
authors.initials: MM
authors.lastname: Avram
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston3Department of Dermatology, Massachusetts General Hospital, Boston.
authors.forename: Lilit
authors.initials: L
authors.lastname: Garibyan
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Martin C
authors.initials: MC
authors.lastname: Mihm
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston3Department of Dermatology, Massachusetts General Hospital, Boston.
authors.forename: R Rox
authors.initials: RR
authors.lastname: Anderson
mesh_terms: D050153:Abdominal Fat / Q000473:pathology* / Q000601:surgery*; D000328:Adult; D001707:Biopsy, Needle; D003452:Cryosurgery / Q000009:adverse effects* / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D006965:Hyperplasia / Q000209:etiology / Q000473:pathology; D007150:Immunohistochemistry; D015187:Lipectomy / Q000009:adverse effects* / Q000379:methods; D008297:Male; D009765:Obesity / Q000601:surgery; D011183:Postoperative Complications / Q000473:pathology; D035583:Rare Diseases; D018570:Risk Assessment