cardiac phase-contrast MRI
MRI technique measuring blood flow velocity and volume. Uses velocity encoding to quantify flow across valves and vessels.
Full Definition
Cardiac phase-contrast MRI is a specialized technique that encodes blood flow velocity into image phase, enabling quantitative measurement of blood flow. By applying bipolar gradients with specific velocity encoding (VENC) values, the technique can measure flow velocities and calculate volumetric flow rates across cardiac valves, great vessels, and intracardiac shunts. Applications include assessment of valvular regurgitation severity, shunt quantification, and evaluation of aortic coarctation. The technique provides both qualitative visualization of flow patterns and quantitative measurements of stroke volume, regurgitant volume, and flow reserve.
Usage
Usage note: Specify VENC settings and measurement plane location for reproducibility.
In Context
- "Cardiac phase-contrast MRI quantified the aortic regurgitant volume at 45 mL per beat." — MRI flow study report
- "Phase-contrast imaging through the pulmonary valve showed Qp:Qs ratio of 2.1:1." — Congenital heart disease evaluation