探讨直接数字化X线摄影在小儿胸片中的价值

目的:探讨在小儿胸片中应用直接数字化X线摄影的临床价值。方法:将我院2014年11月-2015年11月收治的需行胸部检查患儿160例选为研究对象,依据检查方式划分为两组,其中常规组(n=78)行胸部常规X线检查,DR组(n=82)行直接数字化X线摄影,对比两组图像质量。结果:常规组48.7%为甲级片,26.9%为乙级片,23.1%为丙级片,1.3%为废片;DR组89.0%为甲级片,9.8%为乙级片,1.2%为丙级片,无废片。两组甲级片所占比对比差异明显(P0.05)。结论 :在小儿胸片中应用直接数字化X线摄影临床价值明显,可提升图像质量,便于诊断,值得推广。     

浅谈两种X线摄影系统拍摄胸片图像的质量对比效果

目的:探讨在胸片拍摄中采用计算机X线摄影(CR)与直接数字化X线摄影(DR)的质量比较。方法:将我院2013年10月-2015年10月接受胸片检查的患者400例选为研究对象,依据胸片拍摄方式划分为两组,其中CR组与DR组各200例,对比两组胸片图像质量。结果 :CR组5.5%为甲级片,92.5%为乙级片,2.0%为废片;DR组15.0%为甲级片,85.0%为乙级片,无废片,两组甲级片率对比差异明显(P0.05);CR组合格率为95.0%,10张因IP板出现扫描故障而重拍,DR组合格率为100.0%,对比无明显差异(P0.05)。结论:当前拍摄胸片图像主要应用CR与DR,二者有其共性,但是DR图像质量更优,几乎无重拍现象,便于临床诊断,值得推广。     

数字化分角线投照根尖片质量影像因素分析

目的：探讨数字化分角线投照根尖片质量的影响因素，提高根尖片的甲级片率，降低丙级片及废片率，为临床提供更优质的影像。方法：质量控制小组每天至少随机抽取20例分角线投照根尖片进行质量评定。对2020年3月-8月期间评定的总计4541例影像进行统计分析。结果：评定的4541例中，甲级片率为65.29%，乙级片率为20.55%，丙级片率为13.85%，废片率为0.31%。分角线投照根尖片在拍摄技术方面存在的主要问题有曝光不全（球管切迹）、压缩/拉伸变形、邻牙重叠、结构不全等。结论：在拍摄数字化分角线投照根尖片时，应准确把握球管、成像板、患者体位的相对关系，根据个体差异调整拍摄角度，避免出现曝光不全等现象。     

MRI、CT与全数字化乳腺X线摄影在乳腺癌诊断中的临床价值分析

目的:分析讨论乳腺癌诊断中应用MRI、CT和全数字化乳腺X线摄影的临床应用价值。方法:选取本院2017年1月-2018年12月乳腺疾病患者200例,对所有研究对象先后进行MRI、CT和全数字化乳腺X线摄影检查。比较三种检查方式对乳腺癌的诊断率。结果:MRI、CT和全数字化乳腺X线摄影诊断率依次为93.00%、80.50%和77.50%,MRI诊断率明显高于CT和全数字化乳腺X线摄影,P<0.05。结论:MRI能够有效诊断乳腺癌,但MRI检查费用较高,可优先使用CT和全数字化乳腺X线摄影检查。     

数字化X线摄影(DR)双能量成像技术的临床应用价值

目的:分析数字化X线摄影(DR)双能量成像技术的临床应用价值。方法:选择我院2015年3月至2016年5月收治的患者200例,按照数字随机方式将全部患者分成两组,100例对照组患者给予传统X线平片检查,100例实验组患者给予数字化X线摄影双能量成像技术检查,对两组患者的拍片质量进行观察比较,同时对临床诊断率进行统计分析。结果:在图像质量方面,实验组显著优于对照组;另外在临床诊断准确率方面,实验组显著高于对照组。结论:数字化X线摄影双能量成像技术的操作简单方便,拍片质量高,能为疾病的诊治提供质量较高的影像资料,进而让临床诊断率提高,具有临床应用价值。     

观察全视野数字化乳腺X线摄影在乳腺癌诊断中的应用价值

目的:观察全视野数字化乳腺X线摄影用于乳腺癌诊断中的临床价值。方法:以2017年4月-2019年7月为观察时段,选入此时段内我院接纳的50例乳腺癌患者,所有患者均接受全视野数字化乳腺X线摄影及超声检查。结果:乳腺X线摄影诊断符合率明显更高(P<0.05),漏诊率、误诊率明显更低(P<0.05)。结论:在乳腺癌诊断中给予患者全视野数字化乳腺X摄影有较高诊断符合率,不过在隐匿性乳腺癌诊断中依然存在一定漏诊风险。     

DR影像的特点及临床应用

目的:探讨直接数字化X线摄影(DR)在临床运用时的优点,针对实践总结DR影像的特点.方法:选取我科2009年6月～2012年6月期间经X射线检查的9900例患者为研究对象,在相应标准下,统计三片率.结果:统计三片率为甲级95.45％、乙级3.23％、废片1.31％.结论:DR数字化影像技术操作简便、曝光时间短、诊断准确率高,值得临床广泛应用.     

数字化X线摄影在骨外伤诊断价值的分析

目的:分析数字化X线摄影在骨外伤诊断临床价值与应用。方法:选取本院2014年6-12月68例骨外伤病患临床资料,病患都采用数字化X线摄影与常规X线摄影检查,对数字化X线摄影诊断正确率进行总结,并分析数字化X线摄影诊断骨外伤漏诊原因。结果:摄片质量上,数字化X线摄影比常规X线胸片明显要高,检查结果上,数字化X线摄影诊断骨外伤检出率是97.06%,常规X线摄影诊断骨外伤检出率为76.47%。数字化X线摄影检出率比常规X线摄影明显要高,两组结果具备明显差异,具有统计学意义(P0.05),都未出现任何不良反应。结论:在骨外伤诊断中,数字化X线摄影可以取得不错诊断效果,弥补了常规X线摄影不足,提供更为高效摄影质量,对病变可以清晰显示,提升诊断正确率,可作为骨外伤病患X线检查首选,为临床提供更为可靠诊断依据与价值信息,应当得到大力推广及应用。     

移动式数字化X线摄影系统技术平台的构建与应用

目的:为提高床旁X线摄影的图像质量和工作效率,对现有的移动式X线机进行数字化改造,实现床旁数字化X线摄影。方法:通过原有的移动式X线机与无线平板探测器及基于该平板探测器而设计的数字化X线成像系统和曝光同步控制系统,构建组成移动式数字化X线摄影系统技术平台(以下简称移动DR技术平台或移动DR)。结果:移动DR技术平台性能稳定,所拍摄的床旁X线图像清晰,质量较以前的CR模式有较大的提高,而且曝光条件较CR模式低。结论:移动DR技术平台能充分的利用原有移动X线机,所拍摄的床旁X线图像清晰,工作效率大大提高,且辐射剂量大幅降低。     

屏片组合在乳腺摄影中的应用

乳腺X 线摄影是医疗单位用来检查妇女乳房疾病的主要手段。长期以来,由于该类X 线摄影器材(X 光胶片、荧光增感屏、暗盒等)的落后和不配套,影响了卫生系统对乳腺病的防治普查工作。本文简述了X 线摄影屏片的组合原理;介绍了乳腺摄影用的新器材“软X 线乳腺增感屏和乳腺X 光胶片”,以及两者组合应用后,使乳腺X 光照片的清晰度和诊断确诊率得到大幅度提高。并概述了推广该种屏片组合应用的社会效益和前景。     

Results of radiation protection programmes on mammography

In this paper, we present the results of mammography quality control tests related to the work with Portuguese mammography equipment, either in conventional or in digital mammography computed radiography, showing the main differences in the tested equipments. Quality control in mammography is a very special area of quality control in radiology, which demands relatively high knowledge on physics. Digital imaging is changing the standards of the radiographic imaging. Regarding mammography, this is yet a controversial issue owing to some limitations of the digital detectors, like the resolution for instance. A complete set of results regarding radiation protection of the patients submitted to mammography diagnosis is presented. A discussion of the quality image parameters and its interpretation in conventional and digital mammography is presented. In conclusion, we present a sample of results that can be considered as characteristics of mammography equipment in Portugal.     

Can the average glandular dose in routine digital mammography screening be reduced? A pilot study using revised image quality criteria

There is a need for tools that in a simple way can be used for the evaluation of image quality related to clinical requirements in mammography. The aim of this work was to adjust the present European image quality criteria to be relevant also for digital mammography images, and to use as simple and as few criteria as possible. A pilot evaluation of the new set of criteria was made with mammograms of 28 women from a General Electric Senographe 2000D full-field digital mammography system. One breast was exposed using the standard automatic exposure mode, the other using about half of that absorbed dose. Three experienced radiologists evaluated the images using visual grading analysis technique. The results indicate that the new quality criteria can be used for the evaluation of image quality related to clinical requirements in digital mammography in a simple way. The results also suggest that absorbed doses for the mammography system used may be substantially reduced.     

Organisational aspects of mammography screening in digital settings: first experiences of Luxembourg

Luxembourg has been conducting a breast cancer screening programme since 1992, like a large number of other European countries, as early detection and treatment of breast cancer have been proven to reduce mortality. The majority of these screening programmes are based on analogue X-ray technology and have optimised their organisation of transporting, archiving and reading with respect to films. Last decade is marked by enormous developments in digital mammography. Different technologies such as flat panel-, computed radiography- and scanning systems became available. Digital mammography is expected to have a major impact on quality and organisation of breast cancer screening programmes. Screening programmes are now faced with a huge challenge of incorporating the digital technology, including implementation of electronic image exchange, conception of new electronic workflow, establishing adapted quality assurance programmes and training of radiologists and technical personnel. Initial experiences of the Luxembourg approach in organising digital mammography screening and its quality assurance are reported.     

Implementation of the European protocol for quality control of the technical aspects of mammography screening in Bulgaria

The results from the national pilot project on implementation of the European protocol for the quality control (QC) of the technical aspects of mammography screening as well as the European protocol for dosimetry in mammography in Bulgaria are presented. A QC programme for mammography equipment and a standardised measurement protocol were created. The full QC programme was tested on four mammography units of different types and ages. A national survey was performed for entrance surface air kerma (ESAK) on 20 units using a 45 mm PMMA standard phantom. Average glandular dose (AGD) was calculated using the conversion coefficients from the European dosimetry protocol. The survey demonstrated considerable differences in the technical condition of the mammography units that resulted in varying image quality. The measured values of ESAK showed significant variations. Doses for approximately 45% of the units were found to be below the European reference level. The values for AGD ranged from 0.35 to 3.47 mGy. The main problems found were film processing, optical density (OD) control settings and AEC adjustment. The results showed the importance of film OD measurements parallel to dose measurements. The X-ray mammography in the country needs optimisation. Comprehensive quality assurance programme should be adopted in all departments covering permanent QC of the equipment, image quality and breast dose.     

Clinical image quality criteria for full field digital mammography: a first practical application

In order to quantify the clinical quality of full-field digital mammography, a set of image quality parameters is developed. The set consisted of 12 image quality criteria and 8 physical characteristics of the image. The first set interrogates the visibility of anatomical structures and typical characteristics of a digital image, such as noise and saturation of dark and white areas. The second set of criteria evaluates contrast, sharpness and confidence with the representation of masses, microcalcifications and the image. The use of these criteria is reported in a retrospective study, in which the impact of dose on the radiological quality of digital mammograms is evaluated. Fifty patients acquired in a low-dose mode were retrieved and compared with 50 patients acquired in a dose mode that was set 41% higher. The dose affects, more than expected, contrast and sharpness of the image, whereas the visibility of the anatomical structures remains unchanged. With these parameters, quantification of the image quality is possible; however, because of subjectivity of the parameters, only intra-observer comparison and evaluation of the individual parameters rather than the overall results are advised. Together with physical tests of image quality, critical radiological evaluation of the quality should be included in the acceptance process of digital mammography.     

Performance of mammography equipment in the Macedonian breast screening campaign 2008/2009

Breast screening campaign in Macedonia started in the end of 2007 and 19 national mammography departments were included. Contrary to the European Guidelines for Quality Assurance in Mammography Screening, the quality assurance activities were not implemented before the start of the campaign, except at the University Clinic of Radiology, Skopje. The quality control tests were performed for the very first time at 13 mammography units under a licence-obtaining procedure. One of the machines was suspended from clinical and screening practice due to heavy malfunction of the generator, X-ray tube and automatic exposure control (AEC) system. Only 3 of the 13 mammography machines met the criteria for tube voltage (kV) accuracy. Two of the seven AEC systems were calibrated in the optimal optical density (OD) range (OD >1.4). AEC settings corresponded to the recommendations at eight units, while nine units met basic overall image quality criteria. Mean glandular dose (MGD) was higher than the recommended level of 2.5 mGy in four departments. Mean gradient of the film G(0.25-2.0) was below 2.8 at four units. Only two light boxes had a luminance of >1700 cd m(-2) and six rooms had an ambient light level of <50 lx. The findings of this work clearly suggest that the performance of the mammography equipment involved in the campaign in almost 50 % do not supply basic quality criteria for a breast screening programme.     

The use of a figure-of-merit (FOM) for optimisation in digital mammography: a literature review

The use of image quality parameters in digital mammography such as contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR) and detective quantum efficiency (DQE) has been widespread, with the intention of detector evaluation and/or quantitative evaluation of the system performance. These parameters are useful in ensuring adequate system performance when tests are done against international standards or guidelines. Parameters like CNR are relative quantities that lie within a range that is manufacturer and system dependent. The use of a figure-of-merit (FOM) is a relatively new concept as a tool in digital mammography permitting quantitative assessment in terms of image quality and patient dose. This review summarises the available evidence for the use and applicability of an FOM in digital mammography.     

Dose to population as a metric in the design of optimised exposure control in digital mammography

This paper describes a method for automatic optimisation of parameters (AOP) in digital mammography systems. Using a model of the image chain, contrast to noise ratio (CNR) and average glandular dose (AGD) are computed for possible X-ray parameters and breast types. The optimisation process consists of the determination of the operating points providing the lowest possible AGD for each CNR level and breast type. The proposed metric for the dose used in the design of an AOP mode is the resulting dose to the population, computed by averaging the AGD values over the distribution of breast types in the population. This method has been applied to the automatic exposure control of new digital mammography equipment. Breast thickness and composition are estimated from a low dose pre-exposure and used to index tables containing sets of optimised operating points. The resulting average dose to the population ranges from a level comparable to state-of-the-art screen/film mammography to a reduction by a factor of two. Using this method, both CNR and dose are kept under control for all breast types, taking into consideration both individual and collective risk.     

Current challenges of full field digital mammography

Full field digital mammography (FFDM) has advantages over screen-film mammography (SFM), but some important challenges remain. The first challenge is related to the specific characteristics of FFDM. It remains unclear, which shape and limiting values of the modulation transfer function have the most influence on the performance of a detector, such as the effect of the image display on the overall image quality and the effect of processing on cancer detection. In order to assess the image quality of FFDM, we have set up a scoring system. The second challenge is related to screening mammography: is the quality of an image the same when it is viewed on different monitors and with different processing algorithms? Is Computer Aided Diagnosis necessary in a screening environment? In FFDM, the effect of different detectors, processing and display possibilities on the image and on cancer detection are not clearly investigated.     

Global quality control perspective for the physical and technical aspects of screen-film mammography--image quality and radiation dose

The systematic monitoring of image quality and radiation dose is an ultimate solution to ensuring the continuously high quality of mammography examination. At present several protocols exist around the world, and different test objects are used for quality control (QC) of the physical and technical aspects of screen-film mammography. This situation may lead to differences in radiation image quality and dose reported. This article reviews the global QC perspective for the physical and technical aspects of screen-film mammography with regard to image quality and radiation dose. It points out issues that must be resolved in terms of radiation dose and that also affect the comparison.