Hemodynamic assessments of venous pulsatile tinnitus using 4D-flow MRI.

Abstract

To use 4D-flow MRI to characterize hemodynamics of transverse and sigmoid sinus in venous pulsatile tinnitus (PT) patients and to investigate their differences vs healthy controls. A total of 21 patients with venous PT and 11 healthy controls were included in the retrospective study. All participants underwent 4D-flow and magnetic resonance venography scan in a 3.0T magnetic resonance scanner. All visualization, quantification, and analysis of 4D-flow data were performed using dedicated software. Two independent reviewers evaluated the existence of vortex or turbulence. Covariance analysis adjusted for age was used to compare average through-plane velocity (V_{tp_avg}), maximum through-plane velocity (V_{tp_max}), average velocity (V_avg), maximum velocity (V_max), average blood flow (Flow_avg), and pulsatility index (PI) between PT and control group. There were hemodynamic differences between PT patients and healthy controls. Compared with the control group, the PT group showed significantly higher V_{tp_avg}, V_{tp_max}, V_avg, V_max, and Flow_avg, and slightly higher PI. For the assessment of flow pattern, inter-reader reproducibility was excellent (κ = 1.00). Vortex or turbulence was observed in PT patients with good sensitivity (86.4%) and specificity (90.9%). Drainage dominance was more frequently observed in patients (15/21, 71.4%) than healthy controls (4/11, 36.4%). Significant hemodynamic differences were found between venous PT patients and healthy controls with 4D-flow MRI. Hemodynamic conditions could serve as noninvasive biomarkers for diagnosis and treatment evaluation of venous PT. This study provides Class III evidence that 4D-flow MRI accurately identifies patients with venous PT.