VäriDoppler

VäriDoppler is the Swedish term for color Doppler imaging, an ultrasound technique that visualizes blood flow by measuring Doppler shifts in echoes from moving red blood cells. It combines conventional grayscale ultrasound (B-mode) with color-coded flow information, overlaid on the anatomical image to show the direction and relative speed of circulation within vessels and cardiac chambers.

The method relies on Doppler principles applied in real time. By analyzing frequency shifts caused by moving blood cells, VäriDoppler provides qualitative information about perfusion and hemodynamics. The color map typically assigns red to flow toward the transducer and blue to flow away, with variations in brightness indicating velocity; colors and thresholds can vary between devices. Some systems also display multiple colors for complex flow and include a velocity scale bar for reference.

VäriDoppler is commonly used alongside spectral Doppler, which provides quantitative velocity measurements along a specific line. Applications span vascular assessment (patency and stenosis), cardiac evaluation (valvular function and intracardiac flow), obstetrics (placental and fetal circulation), and characterization of tumor vascularity or inflammatory processes. The technique also aids in guiding interventional procedures and planning surgical approaches.

Limitations include dependence on the angle between the beam and flow, reduced sensitivity for very slow flow, and susceptibility to artifacts such as aliasing, blooming, and motion. Image quality is affected by patient movement, depth, and operator technique. Proper probe positioning and standardized settings are important for reliable interpretation.