Objective sinonasal functional outcomes in endoscopic anterior skull‐base surgery: an evidence‐based review with recommendations

BACKGROUND: The use of endoscopic endonasal approaches to the anterior skull base has dramatically expanded in recent years, with clinical endpoints and complication rates that compare favorably to traditional approaches. The impact of the endoscopic approach on sinonasal function has been less rigorously evaluated. The purpose of this study was to systematically analyze the literature evaluating objective sinonasal outcomes in endoscopic anterior skull-base surgery, and provide evidence-based recommendations. METHODS: A systematic review of the literature was performed based on a published guideline for developing an evidence-based review with recommendations. Objective sinonasal outcomes included were olfaction, mucociliary clearance, and nasal airflow. RESULTS: Ten articles were identified addressing objective olfactory outcomes: 2 randomized controlled trials; 6 cohort studies; and 2 retrospective case series. One cohort study investigating mucociliary clearance was identified. Six studies reporting postoperative endoscopic outcomes were identified. CONCLUSION: Based on the available evidence, nasoseptal flap (NSF) elevation with or without use in reconstruction likely leads to impairment in objective olfactory function. Endoscopic sellar and parasellar surgery without the elevation of an NSF may lead to a transient reduction in olfactory function. In the absence of a high a priori risk of cerebrospinal fluid (CSF) leak, it is an option to avoid routine NSF elevation in sellar and parasellar procedures, with preservation of at least 1 vascular pedicle during the approach. Monopolar electrocautery for mucosal incisions may increase the risk of olfactory impairment. If an NSF is used, donor site defect reconstruction may be considered.