Reuse of Nasoseptal Flaps for Endoscopic Endonasal Skull Base Reconstruction

Introduction  Pedicled nasoseptal flap (NSF) placement is a critical component of skull base reconstruction after endoscopic endonasal approaches (EEAs). The effectiveness of NSF reuse has not been thoroughly studied. Prior reports using flaps harvested at one center and reused at another may have technical variability bias. Methods  We identified patients who underwent both their initial and NSF-reused surgeries at Weill Cornell Medical College from 2004 to 2022 using a prospective database of all EEAs. Surgical pathology, intraoperative leak grade, use of cerebrospinal fluid (CSF) diversion and skull base coverage were examined. The primary outcome measure was occurrence of CSF leak. Results  Fourteen patients (six women, eight men) underwent 14 first time and 14 revision operations with median age of 36.6 years (interquartile range [IQR]: 23.9-61.3) at the time of the NSF reuse. The median interval between the first NSF use and reuse was 70.6 months (IQR: 16.6-87). Eight patients were operated on for pituitary adenoma. Nonadenomas included three craniopharyngiomas and one case each of epidermoid, ependymoma, and chordoma. There were 16 high-flow, 8 low-flow intraoperative leaks, and 4 with no leak. CSF diversion was used in 24 operations. There were three postoperative leaks, one after a first operation and two after NSF reuse. All postoperative CSF leaks, whether first or second operations, occurred in cases with both high-flow intraoperative CSF leak and incomplete NSF coverage ( p  = 0.006). Conclusion  NSF reuse is effective at preventing postoperative CSF leak. The primary predictors of leak are high-flow intraoperative leak and inadequate defect coverage with NSF, regardless of the operation number.