Abstract WP217: Hemodynamics of the Internal Jugular Vein in Healthy Subjects Using Quantitative magnetic resonance angiography

Abstract

Objective: To study the hemodynamics of cerebral venous system by evaluation of the internal jugular veins (IJV) using quantitative magnetic resonance angiography (QMRA) in healthy subjects. Methods: 263 healthy subjects (129 females; 134 males; mean age 50 ± 16 years) with no history of cerebrovascular disease were evaluated in supine position with QMRA at 3T. Flow rates of the internal carotid artery (ICA) and vertebral artery (VA) were quantified prospectively with 2D phase contrast MR imaging. IJV flow rates were retrospectively measured from previously acquired 2 D phase contrast imaging of the neck between the C5 and C6 level. Total internal jugular venous flow (TIJVF=LIJV + RIJV) was compared to total cerebral flow (TCBF=ICAs + VAs). Regression analysis was used to examine the effects of age, mean blood pressure (MBP), and other variables on TIJVF. Results: LIJV flow rates (229 ± 141 ml/min) was significantly less than RIJV (362 ± 165 ml/min) (P< 0.0001). TIJVF (592 ± 177 ml/min) was 84% of TCBF (703 ± 115). As expected, TIJVF was significantly dependent on TCBF (p<0.0001). Unlike TCBF, TIJVF did not depend on age (p= 0.3), nor on MBP (p=0.5), or on gender (p=0.6). Conclusions: IJVs are the principle outflow pathway of intracranial blood. Reference values for flows in IJVs and TIJVF may help in the evaluation of conditions characterized by venous outflow obstruction (e.g. venous sinus thrombosis or pseudotumor) or excessive venous output (e.g. arterio-venous fistulae or malformations), as well as investigation of conditions hypothesized to be associated cerebral venous insufficiency, such as multiple sclerosis.