Anatomy of the sellar barrier: From magnetic resonance imaging to the operating room

Background: The sellar barrier concept concerns the correlation between the components of the pituitary fossa roof and the risk of intraoperative cerebrospinal fluid (CSF) leak during pituitary tumor surgery. Our team previously classified the sellar barrier according to its thickness on contrast-enhanced T1-weighted magnetic resonance imaging (MRI) sections into three subtypes: strong, mixed or weak. The purpose of this study is to complement the preoperative analysis of the sellar barrier with T2-weighted MRI sections to enhance our knowledge of the anatomical configuration of the sellar barrier and its correlation with the intraoperative findings. Method: A retrospective descriptive study was performed in which medical records, neuroimaging and surgical videos of patients undergoing endoscopic endonasal surgery for pituitary tumors from January 2021 to January 2024 were reviewed. In all cases, the anatomy of the sellar barrier was evaluated by an expert neuroradiologist using pre-surgical T1-weighted MRI with gadolinium and T2-weighted images with sagittal and coronal cuts. Subsequently, the anatomical structures of the sellar barrier were compared with the direct endoscopic view observed in the operating room. Results: A total of 108 patients were included in this study. According to the preoperative neuroimaging findings, an experienced neuroradiologist classified the type of sellar barrier as strong, mixed or weak. Additionally, the T2-weighted imaging study was systematically implemented to identify the anatomical components of the sellar barrier. We found a high correlation between the preoperative neuroimaging description and the intraoperative endoscopic view of the sellar barrier. We present eight illustrative cases herein. Conclusions: The use of T2-weighted sequences in conjunction with gadolinium-enhanced T1-weighted images enhances the preoperative knowledge of the sellar barrier by discriminating its anatomical components with high precision. As in any neurosurgical procedure, a detailed preoperative neuroimaging study and evaluation is highly recommended in order to offer the best possible treatment to our patients affected by pituitary tumors.