Pozniak M A, Zagzebski J A, Scanlan K A
Department of Radiology, University of Wisconsin Hospital and Clinics, Madison 53792.
Radiographics. 1992 Jan;12(1):35-44. doi: 10.1148/radiographics.12.1.1734480.
Artifacts in spectral and color Doppler imaging can be confusing and lead to misinterpretation of flow information. The authors review these artifacts by considering three main causes: inappropriate equipment settings, anatomic factors, and physical and technical limitations of the modality. Incorrect gain, wall-filter, or velocity scale settings can cause loss of clinically important information or distortion of the tracing. Reflection of the Doppler signal from highly reflective surfaces can create a color Doppler mirror image. Vascular motion can introduce artifactual variation in velocity as the sample volume passes through different velocities in a laminar flow state. Unintentional motion can cause a generalized Doppler shift. Increasing the angle of Doppler interrogation degrades the quality of the tracing and gives the impression of spectral broadening. As angulation approaches 90 degrees, directional ambiguity can occur, suggesting bidirectional flow. Grating and side lobes can interrogate areas unrelated to the sample volume and introduce extraneous Doppler information to the apparent area of interrogation. Recognition of these artifacts is essential to proper interpretation of Doppler information and rendering a correct diagnosis.
频谱和彩色多普勒成像中的伪像可能会造成混淆，并导致对血流信息的错误解读。作者通过考虑三个主要原因来回顾这些伪像：设备设置不当、解剖因素以及该检查方式的物理和技术限制。增益、壁滤波器或速度标尺设置不正确会导致临床重要信息丢失或描记失真。多普勒信号从高反射表面反射可产生彩色多普勒镜像。当样本容积在层流状态下通过不同速度时，血管运动可引入速度的伪像变化。无意的运动可导致普遍的多普勒频移。增加多普勒探测角度会降低描记质量，并给人以频谱增宽的印象。当角度接近90度时，可能会出现方向模糊，提示双向血流。光栅和旁瓣可探测与样本容积无关的区域，并将无关的多普勒信息引入到明显的探测区域。识别这些伪像对于正确解读多普勒信息和做出正确诊断至关重要。
