Abstract TP242: Perfusion Imaging Changes in Cerebral Venous Sinus Thrombosis Associated with Hemorrhage

Introduction: Cerebral venous sinus thrombosis (CVST) is a rare condition in which dural venous sinus obstruction impairs cerebral venous drainage. While routine MRI and CT are commonly used, they provide limited hemodynamic information. Perfusion imaging quantifies hemodynamic parameters such as cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time-to-maximum (Tmax), offering physiologic insight. Venous congestion may produce elevated CBV and MTT, reflecting increased venous pressure and impaired capillary outflow, potentially predisposing to hemorrhage. Prior studies are small and have not evaluated Tmax. We hypothesize that CVST may induce Tmax delays that identify tissues at higher risk for hemorrhagic transformation. Methods: We performed a retrospective chart review using an institutional database. Inclusion criteria included: ICD code of CVST, confirmed diagnosis of CVST by a physician, and available perfusion imaging. Exclusion criteria included: no CVST, absent perfusion imaging, prior intracranial pathology, and exclusionary etiology (trauma, iatrogenic, infectious). Three independent raters assessed each scan for hemorrhage and perfusion changes including CBV, CBF, MTT, and Tmax. Consensus grading was reached through joint review. Associations between imaging parameters and clinical variables were evaluated using statistical analysis. AI tools assisted with abstract editing. Results: From 2009–2024, 517 patients at our institution had ICD codes for CVST. 45 patients met inclusion/exclusion criteria with a total of 50 perfusion scans (12 CT Perfusion, 38 MR Perfusion). Interrater reliability prior to consensus grading ranged from 0.49 to 0.66 for the measured variables. Based on consensus rating, hemorrhage was present in 36% of scans, and 54% demonstrated a perfusion abnormality. Increased CBV, CBF, MTT, and Tmax were observed in 24%, 18%, 28%, and 42% of scans, respectively. Of these parameters, only increased MTT was significantly associated with hemorrhage (p = 0.009, Sensitivity 50%, Specificity 84%). Conclusion: Consistent with prior research, CVST was associated with a variety of perfusion abnormalities. Perfusion changes were often subtle and interrater reliability ranged from moderate to substantial with independent grading. Tmax was the most sensitive parameter, showing the highest frequency of abnormalities. MTT was the only perfusion metric significantly associated with intracranial hemorrhage.