【作者】 白国刚；

【导师】 卢广文；

【作者基本信息】 中国人民解放军第一军医大学 ， 生物医学工程， 2003， 硕士

【摘要】 图像存档与通信系统是近年来随着数字成像技术、计算机技术和通信技术的进步而迅速发展起来的。它在给我们带来巨大便利的同时，也给我们的质量保证工作提出了新的要求。 放射学迄今为止已有100多年的历史，关于传统屏/片体系成像方式质量保证已经系统化、标准化。由于PACS系统出现时间不长，整个PACS行业缺乏一个规范和统一的质量保证标准。主要表现为标准化程度低、兼容性差、数据传输不完整、软阅读显示器分辨率不够等。 为了全面探讨PACS系统质量保证，建立一套完整的质量保证体系，使PACS行业的发展标准化、规范化，本文从PACS的四个主要组成部分研究其质量保证： 1． 图像采集：影像采集主要有四种方式：DICOM采集、非标准数字采集、视频采集、胶片扫描。由于CT、MRI、SPECT、PET等大型医疗设备的质量保证已经系统化、规范化，本节主要研究胶片数字化仪和CR的质量保证。重点分析了胶片数字化仪分辨率对临床诊断的影响，结论是胶片数字化仪扫描分辨率必须为300dpi。同时提出了胶片数字化仪和CR的质量保证方法。 2． 图像传输和存储：由于医学影像的数量很大，增长速度很快。因此必须进行图像压缩以节约存储空间并加快图像传送速度。本节主要探讨了有损压缩的评价，分别比较了CR图像压缩效果和CT图像压缩效果。此外，还简要介绍了PACS系统中图像传输和图像存储的要求。 3． 图像显示和处理：显示工作站是PACS系统中数据流向的最后一环，它的性能直接关系到整个PACS系统的效能，是PACS系统展示其价值的窗口，因此显示工作站的质量保证工作尤其重要。本节首先从工程技术角度研究了工作站显示器的质量保证并提出了一套切实可行的质量保证方法，然后从临床角度对1K和2K显示器、彩显和灰阶显示器进行了比较，提出了适合中国国情的显示器配置。最后提出了显示工作站的性能要求。 4． 图像输出及打印：本节简要了介绍激光相机的质量保证方法。第一军医大学硕L学位论文 本文系统地提出PACS的质量保证概念，首次把ROC方法应用于胶片数字化仪、图像压缩和显示器的质量评价。从工程技术角度探讨胶片数字化仪、CR和PACS显示器的质量保证并实现了一套切实可行的质量保证方法。更多还原

【Abstract】 Picture Archiving and Communication Systems, booming rapidly following the advances of technologies in digital imaging, computer and communication, has benefited us a lot, but is meanwhile challenging us with quality assurance.Radiology, having been developing over 100 years up to now, has got its quality systemized and standardized on conventional screen/film imaging system. At its primary stage, PACS manifests itself with lower standardization, poor compatibility, incompletion of data transmission and poor resolution of the soft-copy monitor, in general, short of uniform and standardized criteria on its quality assurance.In order to establish a complete system of quality assurance and promote the standardization and unification, we have studied PACS quality assurance system with regard to the main four parts it consists of.1. Image AcquisitionIt involves 4 approaches: DICOM acquisition, non-standard digital acquisition, video acquisition and film scanning. Here we just put our eyesight in this chapter on the study on digitizer and CR quality assurance on the grounds that such medical equipment as CT, MRI, SPECT, PET has been systemized and standardized. Therefore, we have focused on the effects of digitizer’s resolution on clinical diagnosis, concluding that digitizer’s resolution is supposed to reach 300dpi and meanwhile coming up with a complete system for film digitizer and CR quality control.2. Image Transmission and SavingThe large amount of medical imaging as well as its rapid growth pushes us compress images for the purpose of saving space and speeding up image transmission. In this chapter, we have explored the evaluation on lossy compression and studied comparatively the effects of CR and CT images compressions respectively. In addition, we have made a brief introduction of requirements for images transmission and saving in PACS.3. Image Display and ProcessionDisplay workstation, acting as the destination the data in PACS system flow into, is a window where PACS system is able to show its value. Its features evidently relate to the function of PACS system. No doubt, the quality assurance of display workstation is of dramatic significance. In this chapter, we begin with the quality assurance of display workstation from the angle of engineering technology; bring out a series of workable quality assurance. Then by clinically comparing IK and 2K monitor, color monitor and monochromatic monitor, we have worked out compatible monitor settings suitable for the situations in China. Consequently, we have concluded the requirements in features of display workstation.4. Image Output and PrintingThis chapter has introduced how to guarantee quality of laser camera.In this thesis, we have put forward the concept of PACS quality assurance. We have taken the lead to employ ROC approaches to film digitizer, quality evaluation of images compression and monitors. Furthermore, we have explored the quality assurance of film digitizer, CR and PACS monitors from the angle of engineering technology and established a series of workable quality assurance.更多还原