title: Complications after polyacrylamide hydrogel injection for soft-tissue augmentation.
abstract: BACKGROUND
  Polyacrylamide hydrogel has gained international attention as a new injectable permanent filler that appears to be ideal for soft-tissue augmentation. However, studies on the safety of polyacrylamide hydrogel injection are limited and inconsistent. In the authors' experience, polyacrylamide hydrogel injections can induce complications.
  
  
  METHODS
  The authors retrospectively reviewed all cases where patients injected with polyacrylamide hydrogel for cosmetic purposes between 2004 and 2007 at other clinics suffered complications that led them to come to the authors' facility. The authors retrieved the patient histories, the duration between injection and presentation in their clinic, the materials and sites that were injected, whether injection was combined with other procedures, the clinical findings of the complications, the preoperative imaging analysis results, the operative methods used to correct the problem, and the chemical analysis of the extirpated injected material.
  
  
  RESULTS
  Of the 15 cases, all were women, except for one man, who was injected in his penis. Four, two, four, and four of the women were injected in their cheeks, nose, eyelids, and breasts, respectively. The product names of the injected materials were Aquamid and Amazingel. Five patients underwent surgery to remove the injected material or a foreign body granuloma.
  
  
  CONCLUSIONS
  There has recently been a steady increase in the number of cases in Asian countries where polyacrylamide hydrogel injection has led to complications necessitating treatment. This is the first report of this phenomenon in Japan. The authors found that once these complications occur, they are difficult to treat. Further studies are needed to elucidate the risks involved in this procedure.
authors.affiliation: Tokyo, Japan From the Department of Plastic, Reconstructive, and Aesthetic Surgery, Nippon Medical School.
authors.forename: Shimpei
authors.initials: S
authors.lastname: Ono
authors.forename: Rei
authors.initials: R
authors.lastname: Ogawa
authors.forename: Hiko
authors.initials: H
authors.lastname: Hyakusoku
mesh_terms: D000180:Acrylic Resins / Q000008:administration & dosage / Q000009:adverse effects*; D000328:Adult; D001940:Breast; D002610:Cheek; D003357:Cosmetic Techniques / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D015745:Granuloma, Foreign-Body / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D007279:Injections, Subcutaneous; D007564:Japan; D008279:Magnetic Resonance Imaging; D008297:Male; D016462:Mammaplasty / Q000379:methods; D008875:Middle Aged; D019736:Prostheses and Implants / Q000009:adverse effects; D012189:Retrospective Studies; D018570:Risk Assessment; D012494:Sampling Studies; D015626:Tissue Expansion; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000180:Acrylic Resins; C016680:polyacrylamide gels