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Secondary Nasoseptal Flaps for Endoscopic Skull Base Reconstruction: Proof of Concept and Evaluation of Outcomes

Objectives: (1) Assess secondary nasoseptal flaps (NSF) as a viable reconstructive option. (2) Evaluate postoperative vascularity of secondary NSFs. (3) Compare cerebrospinal fluid (CSF) leaks and complication rates of secondary NSFs to primary NSFs. Methods: This is a retrospective review of patients from 2009 to 2013 undergoing transsellar approaches for skull base tumors at the University of Pittsburgh Medical Center. In cases where the necessity of a vascularized reconstructive flap was made evident only after tumor resection, the NSF was raised after the tumor had been resected and/or CSF leak had developed (secondary NSF). Outcome measures include postoperative magnetic resonance imaging (MRI) findings, CSF leak rates, and complication rates. Results: Transsellar approaches were performed in 436 patients during this timeframe. Primary NSFs were used to reconstruct 178 patients while 32 patients had secondary NSFs. Postoperative MRI scans were available in 29 of 32 secondary NSF patients; all maintained vascularity on examination of T1 post-contrast images (mean time to MRI 4.9 months). There was no significant difference in CSF leak rate between primary NSFs (3.4%) and secondary NSFs (3.1%) (P = .95). Primary NSFs had a higher overall complication rate (11.7%) compared to secondary NSFs (3.1%), but this was not statistically significant (P = .142). Logistic regression analysis demonstrated no significant effect of flap type, age, or sex on CSF leak rates. Conclusions: Secondary NSFs are a viable reconstructive option for sellar skull base defects. They maintain vascularity as evidenced on postoperative MRI imaging and compare favorably to primary NSFs in regard to CSF leak rates and complication rates.