Effect of Nasoseptal Flap With Nasal Floor Extension on Postoperative Numbness and Recovery of Sensation

OBJECTIVE: Nasoseptal flap (NSF) with floor extension provides wide coverage for skull base reconstruction but transects the nasopalatine nerve, potentially resulting in numbness of the front teeth and palate. The aim of this study was to evaluate the incidence of postoperative numbness, recovery of sensation, and anatomical predictors. STUDY DESIGN: Retrospective cohort study. SETTING: Single tertiary center. METHODS: We retrospectively analyzed 160 patients who underwent endoscopic transseptal skull base surgery and categorized them as non-NSF (n = 75), NSF without floor extension (n = 7), and NSF with floor extension (n = 78). The primary outcome was patient-reported numbness of the front teeth or palate as assessed during hospitalization and at 3 months. The incisive canal, through which paired NPNs from the nasal cavities pass into the oral cavity, was classified on preoperative computed tomography (CT) as single (one channel receiving bilateral nerves), separated (two channels with bilateral separation), or intermediate (Y-shaped channel). RESULTS: Immediate numbness occurred in 5.3%, 14.3%, and 32.1% of those groups, respectively (P < .001). At 3 months, persistent numbness was reported, respectively, in 1.3%, 0%, and 10.4%, with a significant difference between non-NSF and NSF with floor extension (P = .034). Immediate numbness occurred in 29.7% of those with a single canal and 11.3% of those with a separated canal (P = .021). CONCLUSION: NSF with floor extension increased the incidence of numbness and should be avoided when possible. Patients with a single canal on preoperative CT require careful surgical attention.