Takahashi M, Yoshioka S, Bussaka H, Higashida Y, Kamiya M, Tsuneoka M
Department of Radiology, Kumamoto University School of Medicine, Japan.
Med Phys. 1990 Jul-Aug;17(4):681-5. doi: 10.1118/1.596466.
A digital TV tomography system, capable of retrospective reconstruction of multiple digital tomographic images, has been developed and its basic physical characteristics have been evaluated. The multiple tomographic images were formed through retrospective reconstruction of digital data acquired on a linear tomographic x-ray unit and an image intensifier-television system. Digital data were obtained with a series of 30 pulsed exposures during linear motion of the system. A distortion correction algorithm for the convex surface of the image intensifier was developed in order to reduce image distortion. A phantom study showed that the square-wave response at the fulcrum plane was slightly inferior to that in conventional tomography. There was also a slight decrease in the square-wave response away from the fulcrum plane and upon application of a correction algorithm, as compared with the response of the original reconstructed image at the fulcrum plane. The exposure dose for a single image was approximately half that in conventional tomography. Because of many advantages, including low exposure, short examination time, digital image manipulation, and applicability to picture archiving and communication systems, this is likely to become an important method in radiology when further technical refinements have been made.
一种能够对多个数字断层图像进行回顾性重建的数字电视断层扫描系统已被开发出来，并对其基本物理特性进行了评估。多个断层图像是通过对在线性断层X射线装置和影像增强器-电视系统上采集的数字数据进行回顾性重建而形成的。在系统的线性运动过程中，通过一系列30次脉冲曝光获得数字数据。为了减少图像失真，开发了一种针对影像增强器凸面的失真校正算法。体模研究表明，支点平面处的方波响应略逊于传统断层扫描。与支点平面处原始重建图像的响应相比，远离支点平面并应用校正算法后方波响应也略有下降。单个图像的曝光剂量约为传统断层扫描的一半。由于具有低曝光、检查时间短、数字图像处理以及适用于图像存档和通信系统等诸多优点，当进一步进行技术改进后，这很可能会成为放射学中的一种重要方法。
