Institute of Radiation Medicine, Fudan University, Shanghai 200032,People's Republic of China.
Shanghai United Imaging Healthcare, Shanghai 201807, People's Republic of China.
J Radiol Prot. 2021 Jun 1;41(2). doi: 10.1088/1361-6498/abf900.
In this study, a new ATCM phantom was developed to test the performance of the automatic tube current modulation (ATCM) of computed tomography (CT) scanners.. Based on the Chinese reference man and Monte Carlo simulations of x-ray attenuation, a more realistic ATCM phantom made of polymethyl methacrylate was developed. The phantom has a length of 20 cm, and it can be used to measure the dose profile along the central axis using 19 real-time MOSFET detectors. The image noise can be calculated slice by slice in the phantom's center. Test experiments showed that the phantom could initiate tube current modulation under different modulation levels of CT scans, and the actual effects of ATCM could be evaluated with the aid of the dose profile measurements. Using the measured dose profiles and image noise, the preferred dose can easily be identified from a choice of different modulation levels. The new phantom developed in this study can be used to test the ATCM performance of CT scanners, and is useful for further studies of the optimization of CT scan protocols with ATCM.
在这项研究中，开发了一种新的 ATCM 体模，用于测试计算机断层扫描（CT）扫描仪自动管电流调制（ATCM）的性能。......基于中国参考人模型和 X 射线衰减的蒙特卡罗模拟，开发了一种由聚甲基丙烯酸甲酯制成的更逼真的 ATCM 体模。该体模长 20 厘米，可使用 19 个实时 MOSFET 探测器沿中心轴测量剂量分布。在体模中心可以逐片计算图像噪声。测试实验表明，该体模可以在不同的 CT 扫描调制水平下启动管电流调制，并且可以借助剂量分布测量来评估 ATCM 的实际效果。使用测量的剂量分布和图像噪声，可以从不同调制水平中轻松识别出首选剂量。本研究中开发的新体模可用于测试 CT 扫描仪的 ATCM 性能，对于进一步研究使用 ATCM 优化 CT 扫描方案非常有用。
