Effect of Diameter Size on the Unsteady Characteristics of Pulsatile Flow in Curved Human Blood Vessel

Pulse-synchronous tinnitus (PST) has been linked to multiple anatomical variants of the venous outflow tract, including transverse sinus (TS) stenosis and sigmoid sinus (SS) dehiscence. It is unknown if the size of diameter in the TS part at the symptomatic side will result in PST. In this study, a combined experimental and computational approach is adopted to study the blood flow during PST. A parametric study is performed on the diameter size of one PST patient at the symptomatic side. A Reynold-averaged-Navier-Stokes (RANS) flow solver is employed in ANSYS Fluent to simulate the symptomatic side at different TS diameter sizes. Results have shown distinct differences in the flow characteristics (including pressure, turbulent kinetic energy (TKE), velocity and shear stress) between the symptomatic side at different TS diameter sizes. The result provides evidence to the hypothesis that anatomic differences can be an important element in affecting blood flow in the venous outflow tract. Resulted findings reveal the strong connection between the flow characteristics of a dehiscent SS and resultant PST. The findings help to understand the flow physics of PST and provide insightful guidance for surgical interventions.