Dawn S K, Gotway M B, Webb W R
Department of Radiology, San Francisco General Hospital and the University of California, San Francisco 94110, USA.
Respir Care. 2001 Sep;46(9):912-21.
Since its introduction in 1992, spiral computed tomography (CT) scanners constructed with a single row of detectors have revolutionized imaging of thoracic diseases. Current state-of-the-art models use up to 16 detectors and are capable of acquiring 4 contiguous slices of data with each gantry rotation; systems with 8 data acquisition units (and more) are currently in development. The principal advantages offered by these systems are increased scanning speed and the ability to obtain volumetric data in high resolution. These features enable imaging with enhanced contrast concentration, decreased contrast load, decreased respiratory and cardiac motion artifact, and multiplanar and 3-dimensional reconstruction capabilities. Herein we first review the technical aspects of multidetector spiral CT scanning. The arrangement and various combinations of the detector rows are discussed. Key scanning variables, including collimation (slice thickness), pitch (the rate of table travel per gantry rotation divided by the beam collimation), and gantry speed, are briefly addressed in the context of their interrelationships. Comparison is made with single-detector-row systems to emphasize the superior scanning speed and resolution. We then discuss the various clinical applications of multidetector spiral CT, including CT pulmonary angiography, CT aortography, virtual bronchoscopy, and multiplanar and 3-dimensional reconstructions.
自1992年推出以来，单排探测器螺旋计算机断层扫描（CT）扫描仪彻底改变了胸部疾病的成像方式。当前的先进机型使用多达16个探测器，每次机架旋转能够采集4个连续层面的数据；具有8个（及更多）数据采集单元的系统目前正在研发中。这些系统的主要优点是扫描速度提高以及能够以高分辨率获取容积数据。这些特性使得成像具有增强的对比剂浓度、降低的对比剂负荷、减少的呼吸和心脏运动伪影以及多平面和三维重建能力。在此，我们首先回顾多排探测器螺旋CT扫描的技术方面。讨论了探测器排的排列和各种组合。关键扫描变量，包括准直（层厚）、螺距（每机架旋转时检查床移动速度除以线束准直）和机架速度，在它们的相互关系背景下进行了简要阐述。与单排探测器系统进行了比较，以强调其卓越的扫描速度和分辨率。然后我们讨论多排探测器螺旋CT的各种临床应用，包括CT肺动脉造影、CT主动脉造影、虚拟支气管镜检查以及多平面和三维重建。
