The use of fascia lata can minimize olfactory damage in endoscopic endonasal skull base surgery

The purpose of this study was to compare the impact of using fascia lata versus a nasoseptal flap for skull base repair on olfactory function following endoscopic endonasal skull base surgery. Patients who underwent the endoscopic endonasal transsphenoidal approach (EETA) or the extended endoscopic endonasal transsphenoidal approach (EEETA) were included in this study. The study included 80 patients who underwent skull base defect repair using fascia lata, while the control group consisted of 160 patients who underwent skull base defect repair using a nasoseptal flap. Preoperative demographic data, skull base repair techniques, postoperative sinonasal symptoms and the incidence of cerebrospinal fluid (CSF) leakage were compared between the two groups. Olfactory dysfunction was significantly worse at 3, 6 and12 months after surgery than before surgery in the nasoseptal flap repair group, although olfactory function partially recovered at 12 months after surgery. Additionally, we found that non-validated visual analogue scale (VAS, 0-100 mm) and validated cross-cultural smell identification test (CC-SIT) and the butanol threshold test (BTT) olfactory impairment at 12 months after surgery were significantly worse in the nasoseptal flap repair group than in the fascia lata repair group. Furthermore, no significant difference in the incidence of CSF leakage was noted between the two groups. For endoscopic endonasal surgery, the use of a nasoseptal flap for skull base repair can cause severe olfactory impairment. The use of fascia lata for skull base repair can be considered an alternative method to minimize damage to olfactory function.