Rescue Flap Strategy for Skull Base Surgery: Selective Conversion to Nasoseptal Flap Only in Transoperative CSF Leak

Introduction: Cerebrospinal fluid (CSF) leaks are a major complication of transnasal endoscopic pituitary surgery, traditional risk factors are tumor size, invasion, and patient factors such as overweight and diabetes. The classic nasoseptal flap is elevated at the beginning of surgery to ensure vascularized coverage but at the cost of greater nasal morbidity. The “rescue flap” is a selective, vascularized reconstruction technique designed to prevent postoperative leaks while minimizing morbidity, it allows to preserve the vascularity and could be elevated only if reconstruction is required. Objective: Evaluate the effectiveness of selectively use of the nasoseptal flap for intraoperative CSF leaks in skull base surgery. Methods: We reviewed the medical records of 114 patients diagnosed with pituitary adenomas who underwent transnasal endoscopic surgery between 2021-2025 to assess associations between intraoperative CSF leak grade, nasoseptal rescue flap use and postoperative CSF leak. We used Chi-square test to analyze the association between intraoperative leak grade and nasoseptal flap use and students t-test to establish the relationship between weight or BMI and postoperative leaks Results: The mean age was 47.7 years (16–86). Women represented 61%. The mean BMI was 28.0, 18% of the patients had a diagnosis of diabetes. The distribution of intraoperative cerebrospinal fluid leak grades was grade 0 in 64, 1 in 19, 2 in 20, and 3 in 11 cases. Postoperative CSF leak was documented in 5 cases (4.4%), mainly concentrated in the extreme grades (0 and 3); this association was not statistically significant (p=0.10). A nasoseptal flap was used in 30 patients (26%) and showed a proportional relationship with the severity of the intraoperative leak, reaching statistical significance (p