Imaging Institute, Cardiovascular Imaging, Cleveland Clinic, Cleveland, OH 44195, USA.
Cardiol Clin. 2009 Nov;27(4):655-64. doi: 10.1016/j.ccl.2009.06.007.
Recent technical advances in multi-detector row CT have resulted in lower radiation dose, improved temporal and spatial resolution, decreased scan time, and improved tissue differentiation. Lower radiation doses have resulted from the use of pre-patient z collimators, the availability of thin-slice axial data acquisition, the increased efficiency of ECG-based tube current modulation, and the implementation of iterative reconstruction algorithms. Faster gantry rotation and the simultaneous use of two x-ray sources have led to improvements in temporal resolution, and gains in spatial resolution have been achieved through application of the flying x-ray focal-spot technique in the z-direction. Shorter scan times have resulted from the design of detector arrays with increasing numbers of detector rows and through the simultaneous use of two x-ray sources to allow higher helical pitch. Some improvement in tissue differentiation has been achieved with dual energy CT. This article discusses these recent technical advances in detail.
最近多排探测器 CT 技术的进步降低了辐射剂量，提高了时间和空间分辨率，减少了扫描时间，并改善了组织分化。更低的辐射剂量来自于预患者 Z 准直器的使用、薄层轴向数据采集的可用性、基于 ECG 的管电流调制的效率提高以及迭代重建算法的实施。更快的机架旋转和同时使用两个 X 射线源提高了时间分辨率，而通过在 Z 方向应用飞行 X 射线焦点技术，提高了空间分辨率。通过设计具有更多探测器排数的探测器阵列和同时使用两个 X 射线源以允许更高的螺旋桨距，扫描时间缩短。双能 CT 技术在组织分化方面取得了一些改善。本文详细讨论了这些最近的技术进步。
