Characterizing Pulsatile Tinnitus in the Internal Jugular Vein using Hemodynamic Data from CFD and 4D Flow MRI

Pulsatile Tinnitus (PT) occurs when a sound is perceived in the ear that is synchronous with the heartbeat and has no extracorporeal source. The etiology of PT is sometimes traced to abnormalities in the Internal Jugular Vein (IJV). The work herein utilizes new tools from 4D Flow Magnetic Resonance Imaging (MRI) and computational fluid dynamics (CFD) to study hemodynamics in the IJV region in an effort to better characterize potential sources of sound generation in PT. Recent developments in 4D Flow MRI can provide non-invasive qualitative and quantitative characterization of blood flow in complex patient specific vascular geometries. In this work we use a commercially available 4D Flow MRI sequence as well as a novel, in-house, accelerated sequence to measure the velocity field in a PT patient’s IJV. We next employ CFD over the same region with consistent boundary conditions. Velocity fields obtained in-vivo by 4D Flow MRI, in-vitro by MRI of a flow phantom with the same geometry, and by CFD are compared and analyzed to identify important hemodynamic features that may play a role in sound generation in PT.