[Report on the 86th Scientific Assembly and Annual Meeting of the Radiological Society of North America: motion artifact caused by heart pulsation observed on an electron beam and a multidetector-row CT].
Recently developed technologies in CT imaging have allowed higher temporal resolution and less motion artifacts caused by heart pulsation. However, complete deletion of motion artifacts has not altogether been accomplished. In interpreting images, differentiation of motion artifacts and true lesion is essential. In this exhibition, the ascending aorta, outer contour of the heart, valve, lung adjacent to the heart, and other structures in the mediastinum are demonstrated focusing on the characteristics of motion artifact. Images obtained with an electron beam CT (Imatron 150XL) and a MDCT (LightSpeed QX/i, GEMS) are comparatively demonstrated. In electron beam CT, the temporal resolution ranged from 50 msec to 2,000 msec. In multidetector-row CT, half reconstruction algorithm (500 msec) and newly developed algorithm (130 msec) can be applied to reduce temporal resolution, although temporal resolution (800msec) of a full scan is fixed. Degree, shape, and site at which motion artifacts arise are analyzed with respect to the temporal resolution on two different CT systems.


OBJECTIVE
Motion artifacts are correlated with the temporal resolution of the CT scanner. Electron beam and multidetector row CT provides different kinds of solutions to reduce motion artifacts.
Akiyama
Y
Y
Hiroshima University Hospital.
D000465:Algorithms; D016477:Artifacts; D002319:Cardiovascular System / Q000000981:diagnostic imaging*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods*