与IP板相关的CR图像伪影分析及对策

计算机射线照相（CR）获得的影像往往会带有各种伪影,直接影响诊断质量,伪影可能来源于整个CR系统的各个部分,如：成像板（IP）、扫描、读出、处理、擦除、激光照相机等等,而成像板作为CR系统中用于捕俘射线影像信息的传感器,其影响是最关键的,本文集中分析与IP板相关的图像伪影及应对措施。     

胸部DR摄影组织均衡技术(TE)的应用

目的：直接数字X线摄影（DDR）在胸部图像后处理中采用组织均衡技术与标准DR图像、CR图像比较的临床应用价值。方法：设定组织均衡技术中区域及强度参数，以胸部正位标准图像DR、CR片做对照，以选定测试点为依据，对TE片及标准片、CR片进行测评。结果：通过测试点测值，总结出图像形成规律，论证、应用组织均衡技术在临床上提高影像质量，扩展了组织结构信息的丰富程度。意义：利用组织均衡技术应用于图像处理充分显露了数字影像的临床价值，对保障影像诊断的准确提供了新的发展空间。     

高千伏CR和低千伏CR胸部摄影图像现实效果比较

目的:探讨从影像显示效果方面考虑,胸部CR是否有必要使用高千伏摄影.方法:胸部后前位摄影100例,随机分为两组,75KV和120KV各50例,观察对比显示效果.结果:使用75KV进行胸部后前位CR摄影时,肺野外带肺纹理和左心室后肺纹理显示清晰程度不及120KV.结论:从影像视觉评价结果来看,应用CR系统进行胸部摄影,依然应该选择高千伏拍摄较为合适.     

计算机射线摄影（CR）在泌尿造影中的应用

目前,由新的成像技术稀土元素成像板（IP）、数字化处理技术和干法硬拷贝印片设备组成的CR放射成像系统已经在我国医疗系统广泛应用,本文通过其在泌尿系统临床中的实际应用,并与常规屏片照相方法对比,探讨其应用价值和体现其突出的优越性,如：减少病人接受的射线剂量、造影质量更好、提高影像的清晰度、尤其是软组织的反差和层次及分辨率,从而提高显示病灶的能力和诊断的准确率等等。     

CR/DR图像性能检测方法研究

医用数字摄影(CR/DR)系统的广泛应用,每一个环节都可能对影像质量产生影响,使得其照片或者图像的质量控制显得尤为重要。该文研究CR/DR图像性能相关的技术规范或标准,对检测方法和手段进行讨论,对医学计量检定或医院开展质控工作具有一定的积极作用。     

250例计算机X线摄影(CR)照片质量问题的技术分析

2005年对我市抽检出具有代表性的250例CR照片存在的质量问题进行了总结、分类，并进行了技术分析。归纳为一、曝光条件选择不当。二、调试技术问题。三、摆位标准问题。四、其他技术因素。目的为同道开阔技术视野，提高照片的影像质量。     

190例计算机X线摄影(CR)照片质量问题的综合分析

计算机X线摄影(CR)照片影像质量是当前数字影像系列中常规且重要的内容。本文对在190例胸片、腰椎、膝关节正侧位照片质控中发现的较为普遍的问题，进行归纳、检测、对照，综合分析。     

工业CR技术最新动态

概述工业计算机射线照相(CR)技术的最新进展,包括CR成像板荧光体结构的改进,信噪比和分辨率的提高,激光扫描器的多成像板同时输入、扫描和数字图像输出,使得对射线照相质量和灵敏度有较高要求、且对检测速度和周期也要兼顾的承压设备焊缝检测,有了稳定可靠的新基础。EN和ASME有关CR标准的推出,又为焊缝实施CR检测提供了法定技术依据。本文旨在为国内承压设备加速推广应用CR检测起推波助澜作用。     

南京军区南京总医院举行CR临床应用研讨会

南京军区南京总医院于２００１年１０月２４日举行CR临床应用研讨会,与会者来自各级医院的院长及放射科主任６０余人。上海岱嘉医学影像系统有限公司总经理翁思跃先生到会祝词,与会者分别听取了南京军区南京总医院医学影像科袁仁松副主任技师的“使用计算机X线摄影ACR２０００i的体会”,上海岱嘉医学影像系统有限公司副总经理尹宏先生的“CR技术及进展”、“ADV影像诊断工作站的特性及临床应用”,南京军区南京总医院医学影像科主任陈君坤教授的“CR引进、选型及临床应用”的专题报告,引起与会者的广泛兴趣,他们认为：CR是我国现…     

1140例计算机X线摄影(CR)照片常见问题研讨

继在本刊2004年第四期发表“190例计算机X线摄影（CR）照片质量问题的综合分析”后，续写本文再对1140例CR照片质控进行分类、分项剖析。     

Correlation of image quality with exposure index and processing protocol in a computed radiography system

The correlation of image quality with the exposure index (EI)and the processing protocol was investigated in a Kodak computedradiography (CR) system using clinical radiographs and a waterphantom containing an aluminium and a copper stepwedge. Thephantom was exposed to different dose levels and the acquiredimages were processed using four clinical protocols. The qualityof these images was evaluated in terms of image brightness,contrast and noise. In clinical radiographs, there was no straightforwardcorrelation of image quality with EI. In phantom images, higherEI values improved contrast and reduced noise but after a pointthis improvement does not justify the implied increase in patientdose. Image brightness, contrast and noise were also stronglydependent on the processing protocol. To obtain the images ofsatisfactory quality with the Kodak CR system, a dose slightlyhigher than those used in 400 relative speed screen–filmsystems and a processing protocol designated for the specificradiographic examination are required.     

1140例计算机X线摄影(CR)照片常见问题研讨

我们曾经对190例计算机X线摄影(CR)照片问题进行综合分析研究(文章发表于本刊2004年第4期),本文是对该项研究的继续,重点是介绍CR照片的测试方法、评价依据、评价内容,并在此基础上在对1140例CR照片质量进行分类、分项分析,进一步探讨CR照片常见问题产生的原因及解决方法,以求提高照片质量。     

计算机X线摄影头颅标准照片的测定

目的：计算机X线影像（CR）应用于头颅、制定标准以提供临床丰富诊断信息的照片。方法：选择三组不同曝光条件照射、制定标准测试点通过仪器对影像密度测试，并与普通屏－片进行对照、综合评价。结果：通过CR头颅正侧位片的测定，总结出头颅数字影像的标准。结论：计算机X线摄影在医学影像领域中越加占主导地位，以某一部位、位置的照片质量标准作为基点，以照片质量标准的检测条件作为原则，建立一整套完整的数字影像质控体系。     

Comparison of full field digital (FFD) and computed radiography (CR) mammography systems in Greece

The purpose of this study is to evaluate and compare the performance of 52 full field digital (FFD) and computed radiography (CR) mammography systems checked by the Greek Atomic Energy Commission with respect to dose and image quality. Entrance surface air kerma (ESAK) was measured and average glandular dose (AGD) was calculated according to the European protocol on dosimetry in mammography. The exposures were performed using the clinical protocol of each laboratory. The image quality was assessed by the total score of resolved phantom structures incorporated in an American College of Radiology accreditation phantom. The mean ESAK values for FFD and CR systems were 4.59 ± 1.93 and 5.0 ± 1.78 mGy, respectively, whereas the AGD yielded a mean value of 1.06 ± 0.36 mGy for the FFD and 1.04 ± 0.35 mGy for the CR systems. Considering image quality, FFD systems indicated a mean total score of 13.04 ± 0.89, whereas CR systems a mean total score of 11.54 ± 1.06.     

Status and prospects of digital detector technology for CR and DR

Projection radiography is in the middle of the transition from conventional screen-film imaging to digital image acquisition modalities, mainly based on imaging plates (computed radiography, CR) and flat-panel detectors (direct radiography, DR). Cassette-based CR has been available for the past 20 y, and constitutes the major part of direct radiography installations in hospitals today. direct radiography systems based on large-area amorphous silicon active matrix arrays are commercially available for the last 5 y and exist basically in two different types: with scintillators or photoconductors as X-ray conversion material ('indirect' or 'direct' type). direct radiography systems allow for improved image quality and/or dose reduction due to their high detective quantum efficiency and enable faster workflow because of instant image availability. However, new technology developments are improving the performance for CR systems as well, rendering it competitive to direct radiography in many practical aspects. Therefore, it is assumed that the CR and direct radiography systems will coexist for many years to come. This paper reviews the digital detector technologies and the possible future directions of development.     

Optimisation strategies introduced for CR at health care centres in Estonia

In recent years, starting from 2001, conventional film-screen radiography has been rapidly replaced by digital (mostly by computed radiography, CR) techniques in Estonia. New strategies for optimisation and quality assurance for digital radiography have been introduced by the DIMOND III and SENTINEL partners recently. It includes consideration to diagnostic requirements of a given clinical situation, but also objectivation and standardisation of image quality, e.g. using CDRAD test phantom, and constancy testing. The aim of this work is to evaluate the performance of an automatic exposure control (AEC) at different sensitivities when used with the Fujifilm CR system. Image quality, using threshold contrast-detail detectability (TCDD) and signal-to-noise ratio squared related to dose (SNR(2)/D), was also investigated for different sensitivities and tube potential values for this combination. Based on the image evaluation data, optimum speed modes for the organ programme settings have been proposed.