Multimodal Management and Predictors of CSF Leak Following Endoscopic Endonasal Transsphenoidal Surgery for Pituitary Adenomas

Abstract

OBJECTIVE: Cerebrospinal fluid (CSF) leakage remains a significant complication of endoscopic endonasal transsphenoidal surgery (EETS) for pituitary adenomas. This study evaluated incidence, predictors, and outcomes of intraoperative and postoperative CSF leaks, focusing on reconstruction strategies and intraoperative detection performance. METHODS: A retrospective analysis was conducted on 414 consecutive patients who underwent EETS for pituitary adenomas between 2017 and 2025 at a tertiary referral center. Intraoperative CSF leaks were graded (0-III) and managed using 5 reconstruction modalities ranging from no repair to four-layer closure (fat, fascia lata, autologous bone, and vascularized nasoseptal flap). Multivariate logistic regression was used to identify predictors of postoperative CSF rhinorrhea. RESULTS: Intraoperative CSF leaks occurred in 25% of patients, while postoperative rhinorrhea developed in 3.1%. Larger tumor size and prior transsphenoidal surgery were independently associated with postoperative leakage. Full multilayer reconstruction was associated with lower observed odds of postoperative leak (OR = 0.16, P = 0.038), although subgroup size was limited. Notably, 46% of postoperative leaks occurred without a detectable intraoperative leak. Absence of intraoperative leakage demonstrated a high negative predictive value (98%), whereas its presence showed a low positive predictive value (6.9%). CONCLUSION: A leak-guided, patient-specific reconstruction strategy is associated with low rates of postoperative CSF rhinorrhea. While multilayer closure may be beneficial in selected high-risk cases, the occurrence of occult leaks highlights limitations of intraoperative detection and supports the importance of individualized surgical judgment and tailored reconstruction strategies.