title: The effect of hyaluronan hydrogel on fat graft survival.
abstract: BACKGROUND
  Autologous fat transplantation is a common technique for soft tissue augmentation in aesthetic and reconstructive surgery; however, the degree of fat graft take can be unpredictable. Hyaluronan has been shown to be a promising cell carrier in adipose tissue engineering.
  
  
  OBJECTIVE
  The authors investigate the effect of a hyaluronan hydrogel on fat graft survival, angiogenesis, and volume maintenance in a rat model.
  
  
  METHODS
  Fat was harvested from the groins of 27 rats, processed, and injected beneath the animals' dorsums to form 2 grafts: 1 containing fat alone and 1 containing fat and hyaluronan hydrogel in a 1:1 mix (fat-HA). The grafts were scanned in vivo under high-resolution computed tomography at baseline and prior to euthanasia at 4, 12, and 20 weeks to measure total fat-HA graft volume as well as the volume of the fat component alone. Histological studies were performed after sacrifice to evaluate fat necrosis and blood vessel density.
  
  
  RESULTS
  All grafts were clinically viable. Overall, fat necrosis was significantly reduced in the fat-HA grafts compared with the grafts containing fat alone (P < .001). This difference was most profound at 4 weeks (P = .008) but did not reach statistical significance at 12 and 20 weeks. At 12 weeks, blood vessel density in the fat-HA grafts was significantly greater than in the grafts containing fat alone (P = .016), but this did not reach statistical significance at 4 or 20 weeks. At 20 weeks, the fat component of the fat-HA graft had significantly less volume loss than the fat-alone graft (P = .008).
  
  
  CONCLUSIONS
  When mixed with fat, hyaluronan hydrogel can improve early fat graft survival and may enhance vascularity and prolong volume maintenance.
authors: Department of Plastic Surgery at the Cleveland Clinic, Ohio, USA. mo.alghoul@gmail.com
authors: Mohammed
authors: M
authors: Alghoul
authors: Amanda
authors: A
authors: Mendiola
authors: Rahul
authors: R
authors: Seth
authors: Brian P
authors: BP
authors: Rubin
authors: James E
authors: JE
authors: Zins
authors: Anthony
authors: A
authors: Calabro
authors: Maria
authors: M
authors: Siemionow
authors: Shashidhar
authors: S
authors: Kusuma
mesh_terms: D000273:Adipose Tissue / Q000098:blood supply / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000637:transplantation*; D000818:Animals; D001672:Biocompatible Materials; D003357:Cosmetic Techniques; D006085:Graft Survival / Q000187:drug effects*; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D020100:Hydrogels; D007267:Injections; D008297:Male; D009336:Necrosis; D018919:Neovascularization, Physiologic / Q000187:drug effects; D051381:Rats; D011917:Rats, Inbred Lew; D019651:Plastic Surgery Procedures / Q000379:methods*; D013997:Time Factors; D020858:Tissue and Organ Harvesting; D014057:Tomography, X-Ray Computed; D014182:Transplantation, Autologous
chemical_list: D001672:Biocompatible Materials; D020100:Hydrogels; D006820:Hyaluronic Acid