Schultz E, Fischer P, Lackner K
Computertomographie. 1982 Jun;2(2):76-82.
This paper describes results of measurements characterising the image properties of a CT apparatus triggered by an "R-peak simulator". For this purpose, a phantom was constructed in which--as straightforward simulation of a cardiac wall movement--a plate made of plexiglass of 5 mm wall thickness moves to and fro with a frequency nu (1 s-1 less than or equal to nu less than or equal to 2 s-1) and an amplitude of A = 10 mm. The number of scanning cycles during a measurement could be varied between 2 and 9. It was evident that the measured density values as well as the positions of the plate which could be ascertained from the CT images in the various phases of movement, especially at low frequencies and a large number of cycles, agree well with the real values; however, it was also found that both at the measured density values and the positions of the plate as seen from the CT images, systematic deviations occur, especially at high frequencies and a small number of scanning cycles.
本文描述了对由“R波模拟器”触发的CT设备的图像特性进行测量的结果。为此，构建了一个体模，其中——作为对心脏壁运动的直接模拟——一块壁厚5毫米的有机玻璃板以频率ν（1秒的倒数小于或等于ν小于或等于2秒的倒数）和幅度A = 10毫米来回移动。一次测量期间的扫描周期数可以在2到9之间变化。很明显，在运动的各个阶段，特别是在低频和大量周期的情况下，从CT图像中可以确定的测量密度值以及板的位置与实际值非常吻合；然而，还发现，无论是测量的密度值还是从CT图像中看到的板的位置，都会出现系统偏差，特别是在高频和少量扫描周期的情况下。
