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Artifacts often appear in images generated by contemporary IVUS devices and can interfere in imaging interpretation and measurements (Figure 8.1).

Figure 8.1 Four examples of artifacts from Gary Mintz’s Atlas of Intracoronary Ultrasound, CRC Press, 2004. In (a), ring‐down artifacts in an electronic‐array system image, near‐field bright halos (arrows) close to the face of the catheter can obscure the area immediately adjacent to the catheter. In (b), non‐uniform rotation distortion (NURD) occurs only with mechanical systems. Part of the image is expanded causing deformation of the image in its circumferential view—the image appears elliptical (arrows). In (c), reverberations are repetitive echoes of the same structure. This is an example of reverberations from calcium. The arcs of calcium are indicated by the arrows a, and the false structures (reverberations) are indicated by arrows b. (d) Longitudinal image reconstruction (or L‐mode) is shown. There is excessive motion of the transducer (a) relative to the artery, causing zigzag or sawtooth appearance (white arrows). This artifact is more of a problem with the right and circumflex arteries, because of the wide atrioventricular groove movement between systole and diastole.