Fat as a Biological Dressing: A Novel Adjunct to Skull Base Reconstruction

Background: Abdominal fat is a reservoir of stem cells and growth factors that can be used to promote healing. It is routine practice amongst our skull base team to use a fat graft as a biologic dressing as an adjunct to the nasoseptal flap for reconstruction of intraoperative cerebrospinal fluid (CSF) leak.

Objective: To assess the rhinological outcomes of using an abdominal fat graft as a biologic dressing for complex skull base repairs, in addition to a nasoseptal flap.

Methods: A three-year retrospective chart review of patients who had undergone pituitary surgery between June 1st, 2016 and June 1st, 2019. Inclusion criteria included all pituitary surgeries that had a nasal septal flap and completed a Sino-Nasal Outcome Test score (SNOT-22). Preoperative and postoperative SNOT-22 scores were collected at each clinic visit. Each patient underwent an expanded endonasal approach and resection of their pituitary mass, as well as a reconstruction using a dural matrix graft, nasoseptal flap, and abdominal fat graft as a biologic dressing. They were then packed with stented merocels bilaterally for approximately one week. Follow-up visits to clinic occurred at 1 week, 2 weeks, 4 weeks, 3 months, and 6 months from time of surgery. Debridements occurred at follow-up visits for the first month postoperatively and on an as needed basis. Surgery and follow-up were done by one skull base team at a large quaternary health system serving the area from Northern Illinois to the Upper Peninsula of Michigan. For our statistical analysis, patients were divided into two groups: those that had received a fat graft versus those who did not. Rhinologic data were then compared between the two groups.

Results: There was no significant difference in total, rhinological or quality of life SNOT-22 patient outcomes when comparing patients who had received a fat graft and those that did not (p = 0.946, 0.6591, and 0.4833). Only 57 pituitary patients completed a SNOT-22, with 14 of those having an intraoperative CSF leak where both a nasoseptal flap and an abdominal fat graft were used for reconstruction. There were only two postoperative CSF leaks that required revision due to intercranial hypertension and previous radiation exposure.

Conclusion: The use of abdominal fat as a biological dressing has several advantages with limited detrimental effects. There appears to be no evidence thus far of change in longtime rhinologic outcomes as a result of its use. The technical nuances of this technique are important to ensuring successful outcomes.