Norton M Y, Walton S, Evans N T
Department of Biomedical Physics, University of Aberdeen, UK.
Eur J Nucl Med. 1988;14(9-10):472-6. doi: 10.1007/BF00252391.
An ECG gated tomographic system is described and its application to routine diagnosis of cardiac wall dyskinesis discussed. The tomographic sections are gathered by a single section scanning system (Aberdeen Section Scanner). Technetium labelled red blood cells are used as the imaging agent. The time of the occurrence of the ECG R-wave is superimposed on the tomographic projection data stream and the gated images produced subsequently. The average patient study requires 15 min. Images at 8 phases of the cardiac cycle are generated at each of 5 levels, 16 mm apart, covering the length of the left ventricle. The images are stored as a three dimensional matrix and may be analysed in sections at any orientation. Fourier analysis of computer generated short axis sections are used to generate a set of coefficients describing the contraction of the left ventricle. The coefficients for each patient study are displayed as a series of two dimensional polar images, schematically displaying the spatial distribution of the coefficient over the left ventricle. These polar images are further analysed by comparison with distributions obtained from normal patient studies. The calculated deviations from the normal are then used to diagnose the magnitude and position of any dyskinesis. Initial results show that the tomographic system is capable of routinely detecting inferior cardiac wall dyskinesis, showing an advantage over non tomographic techniques.
描述了一种心电图门控断层扫描系统，并讨论了其在心脏壁运动障碍常规诊断中的应用。断层扫描切片由单切片扫描系统（阿伯丁切片扫描仪）采集。用锝标记的红细胞作为成像剂。心电图R波出现的时间叠加在断层扫描投影数据流和随后产生的门控图像上。对患者的平均检查时间为15分钟。在心脏周期的8个时相，于间隔16毫米的5个层面上各生成图像，覆盖左心室的长度。图像以三维矩阵形式存储，并可在任何方向进行切片分析。对计算机生成的短轴切片进行傅里叶分析，以生成一组描述左心室收缩的系数。每个患者研究的系数以一系列二维极坐标图像显示，示意性地展示系数在左心室上的空间分布。通过与正常患者研究获得的分布进行比较，对这些极坐标图像进行进一步分析。然后，将计算得出的与正常情况的偏差用于诊断任何运动障碍的程度和位置。初步结果表明，该断层扫描系统能够常规检测下壁心肌运动障碍，显示出优于非断层扫描技术的优势。
