Abstract WP224: Transverse Sinus Hypoplasia as a Predisposing Factor for Cerebral Venous Thrombosis

Abstract

Background: Transverse sinuses (TS) are frequently asymmetric. Hypoplasia or aplasia of TS is a common anatomical variation, right TS is dominant in 61% of cases. The relationship between hypoplastic TS and cerebral venous thrombosis is not well established. Hypothesis: Transverse sinus hypoplasia is a predisposing factor for ipsilateral transverse sinus thrombosis Methods: We retrospectively evaluated 27 confirmed cases with isolated transverse sinus thrombosis and 54 age-and-sex matched controls, treated in a Neurological tertiary center from 2010 to 2015. A stroke neurologist and a neuroradiologist measured TS using an MRI sequence (Inhance 3D Inflow IR); interrater reliability was calculated using Bland-Altman plots. Hypoplasia was defined as a transverse sinus diameter less than 50% of the cross-sectional diameter of the lumen of the distal superior sagittal sinus. Univariate analysis was performed to evaluate the association between transverse sinus hypoplasia (TSh) and thrombosis. Results: There was a good inter-rater reliability (p=0.55 on the Bland-Altman plot by ANOVA test). There were a total of 45 left hypoplastic transverse sinuses (TS) (19 [70.4%] cases vs. 26 [48.1%] controls), and 16 right hypoplastic TS (11 [40.7%] cases vs. 5 [9.3%] controls). Ipsilateral thrombosis was present in 9 (33.3%) right and 15 (55.5%) left hypoplastic transverse sinuses. Transverse sinus thrombosis was more likely to be present when associated with left TSh (RR 2.57, 95% CI 1.17-5.69; p=0.001), than right TSh and ipsilateral thrombosis (RR 0.15, 95% CI 0.04-0.57; p<0.001). Conclusion: Isolated transverse sinus hypoplasia might be a predisposing factor for ipsilateral transverse sinus thrombosis.