phase-contrast MRI
Also written as: PC-MRI
An MRI technique that uses phase information to measure blood flow velocity and volume.
Full Definition
Phase-contrast MRI (PC-MRI) is a specialized magnetic resonance imaging technique that exploits the phase shift of moving spins to quantify blood flow velocity and volume. The technique applies bipolar gradients that cause stationary tissue to maintain zero phase while moving blood acquires a phase shift proportional to its velocity. PC-MRI can measure flow in any direction and provides both qualitative flow visualization and quantitative measurements of flow rate, stroke volume, and regurgitant volumes. In cardiovascular imaging, PC-MRI is particularly valuable for assessing valvular function, quantifying shunts, and measuring flow in great vessels. The technique requires selection of appropriate velocity encoding (VENC) values to avoid aliasing artifacts.
Usage
Usage note: Specify VENC settings and flow measurement locations; distinguish from other MRA techniques.
In Context
- "Phase-contrast MRI demonstrated severe aortic regurgitation with a regurgitant volume of 65 mL." — Cardiac MRI report
- "PC-MRI flow measurements across the aortic valve showed good correlation with echocardiographic findings." — Comparative imaging study