Efficacy of autologous fat graft injection in the treatment of anovaginal fistulas.

[BACKGROUND] Injection of autologous fat is an established method within plastic surgery for soft tissue augmentation. The aim of the present study was to determine whether transperineal fat graft injection could promote healing of anovaginal fistulas.

[METHODS] The procedures were performed at the University Hospital of North Norway, Tromsø, Norway, and at Aarhus University Hospital, Aarhus, Denmark, between May 2009 and September 2016. After abdominal liposuction, fat was injected around the fistula tract that was finally transected percutaneously with a sharp cannula and fat injected between the cut parts. The internal opening was closed with a suture. Patients had a minimum follow-up of 6 months after last fat graft injection.

[RESULTS] Twenty-seven women underwent 48 procedures. The cause of fistula was obstetric (n = 9), abscess (n = 9), Crohn's disease (n = 7), radiation for anal cancer (n = 1) and endoscopic surgery after radiation for rectal cancer (n = 1). The mean amount of injected fat was 73 ml (SD ± 20 ml), and operating time was 63 min (SD ± 21 min). At median follow-up of 20 months (range 6-87 months) after the last injection, fistulas were healed in 21 women (77%), in 8 women after just one procedure. Healing was achieved in 6 of 7 women (86%) with Crohn's disease and in both women who had undergone radiation therapy. One woman developed an abscess and additional trans-sphincteric fistula 8 weeks after injection.

[CONCLUSIONS] Fat graft injection for anovaginal fistulas is effective and safe.