image quality

图像质量
  • 文章类型: Journal Article
    计算机断层扫描(CT)图像重建技术的最新进展是深度学习图像重建(DLIR)算法。由于迭代重建(IR)技术的缺点,例如负图像纹理和非线性空间分辨率,DLIR正在逐渐取代它们。然而,DLIR在头部和胸部CT中的潜在应用需要进一步检查。因此,该研究的目的是回顾DLIR对辐射剂量(RD)的影响,图像噪声(IN),以及在头部和胸部CT检查中与IR和FBP进行比较的研究结果。
    我们在PubMed中进行了详细的搜索,Scopus,WebofScience,科克伦图书馆,和Embase查找2017年至2023年间使用DLIR进行头部和胸部CT检查报告的文章。使用系统审查和荟萃分析(PRISMA)指南的首选报告项目从入围研究中检索数据。
    在搜索的196篇文章中,共包括15篇文章。总共包括1292个样本量。14篇被评为高,1篇被评为中等质量。所有研究都将DLIR与IR技术进行了比较。5项研究比较了DLIR与IR和FBP。综述显示DLIR提高了智商,CT头部和胸部检查的RD和IN降低。
    DLIR算法显示,与IR和FBP相比,低剂量CT头部和胸部检查的智商明显增强,IN降低。DLIR显示出通过降低辐射风险和提高诊断准确性来增强患者护理的潜力。
    UNASSIGNED: The most recent advances in Computed Tomography (CT) image reconstruction technology are Deep learning image reconstruction (DLIR) algorithms. Due to drawbacks in Iterative reconstruction (IR) techniques such as negative image texture and nonlinear spatial resolutions, DLIRs are gradually replacing them. However, the potential use of DLIR in Head and Chest CT has to be examined further. Hence, the purpose of the study is to review the influence of DLIR on Radiation dose (RD), Image noise (IN), and outcomes of the studies compared with IR and FBP in Head and Chest CT examinations.
    UNASSIGNED: We performed a detailed search in PubMed, Scopus, Web of Science, Cochrane Library, and Embase to find the articles reported using DLIR for Head and Chest CT examinations between 2017 to 2023. Data were retrieved from the short-listed studies using Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines.
    UNASSIGNED: Out of 196 articles searched, 15 articles were included. A total of 1292 sample size was included. 14 articles were rated as high and 1 article as moderate quality. All studies compared DLIR to IR techniques. 5 studies compared DLIR with IR and FBP. The review showed that DLIR improved IQ, and reduced RD and IN for CT Head and Chest examinations.
    UNASSIGNED: DLIR algorithm have demonstrated a noted enhancement in IQ with reduced IN for CT Head and Chest examinations at lower dose compared with IR and FBP. DLIR showed potential for enhancing patient care by reducing radiation risks and increasing diagnostic accuracy.
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  • 文章类型: Journal Article
    儿科介入心脏病学程序在诊断和治疗儿童先天性心脏病中是必不可少的;然而,它们引起了对潜在辐射暴露的担忧。在血管造影中管理辐射剂量和评估图像质量对于安全有效的干预措施至关重要。本系统综述旨在全面分析当前对表征透视引导的儿科心脏介入手术中使用的X射线系统相关的物理图像质量度量的理解。考虑文献中报道的影响这一结果的主要因素。在Scopus和WebofScience中搜索,使用相关关键词和纳入/排除标准,在2000年至2022年间发表了14篇相关文章。报告的物理图像质量度量是噪声,信噪比,对比,对比噪声比,和高对比度的空间分辨率。研究了影响图像质量的各种因素,如聚甲基丙烯酸甲酯厚度(通常用于模拟水等效组织厚度),操作模式,抗散射网格的存在,和管电压。使用这些指标进行客观评估,确保对影响图像质量的主要因素进行公正评估,改善荧光X射线系统的表征,并在手术过程中帮助做出知情决策以保护儿科患者。
    Pediatric interventional cardiology procedures are essential in diagnosing and treating congenital heart disease in children; however, they raise concerns about potential radiation exposure. Managing radiation doses and assessing image quality in angiographs becomes imperative for safe and effective interventions. This systematic review aims to comprehensively analyze the current understanding of physical image quality metrics relevant for characterizing X-ray systems used in fluoroscopy-guided pediatric cardiac interventional procedures, considering the main factors reported in the literature that influence this outcome. A search in Scopus and Web of Science, using relevant keywords and inclusion/exclusion criteria, yielded 14 relevant articles published between 2000 and 2022. The physical image quality metrics reported were noise, signal-to-noise ratio, contrast, contrast-to-noise ratio, and high-contrast spatial resolution. Various factors influencing image quality were investigated, such as polymethyl methacrylate thickness (often used to simulate water equivalent tissue thickness), operation mode, anti-scatter grid presence, and tube voltage. Objective evaluations using these metrics ensured impartial assessments for main factors affecting image quality, improving the characterization of fluoroscopic X-ray systems, and aiding informed decision making to safeguard pediatric patients during procedures.
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  • 文章类型: Systematic Review
    目的:X射线照相术中通常使用抗散射网格来减少患者产生的散射X射线。然而,网格的存在意味着患者剂量随后增加。最近,几个制造商已经开发了能够在不使用传统网格的情况下校正散射X射线的软件。此范围审查旨在系统地绘制评估散射校正软件的研究图,并确定任何现有的知识差距。
    方法:此范围审查涉及在PubMed中进行系统搜索,Scopus,和Webofscience揭示与研究问题相关的研究。包括在01.01.2000和31.12.2021之间发表的用于X射线成像的X射线散射校正软件的文章。PRISMA模型和PICO框架的一部分被用来建立资格标准。使用结构化汇总表从所选文章中提取数据。
    结果:在本范围审查中,20年的X线常规X线摄影文献。数据综合中包括11篇文章。纳入研究的研究人群各不相同:患者,图像质量幻影和解剖幻影。发现X射线散射校正软件的临床应用仅限于特定的身体部位(颈椎,胸部,肩膀,腰椎,髋关节和骨盆)。散射校正软件在图像质量和减少辐射剂量方面似乎是有效的。然而,传统的网格仍然提供更高的图像质量。
    结论:X射线散射校正软件可能是有效的,并为某些情况或临床情况提供了潜在的益处。
    OBJECTIVE: An anti-scatter grid is often used in X-ray radiography to reduce the scattered X-rays generated from the patient. However, the presence of a grid means the patient dose subsequently increases. Recently,severalmanufacturers have developedsoftwarethat is capable of correctingfor scattered X-rays withouttheuse ofa conventional grid. This scoping review aims to systematically map the research assessing scattering correction software and to identify any existing knowledge gaps.
    METHODS: This scoping review involved conducting a systematic search in PubMed, Scopus, and Web of science to reveal studies that were relevant to the research question. Articles published between 01.01.2000 and 31.12.2021 examining X-ray scatter correction software for X-ray imaging were included. A part of the PRISMA model and PICO framework were utilised to establish eligibility criteria. A structured summary table was utilised to extract data from the selected articles.
    RESULTS: In this scoping review, 20 years of literature in X-ray conventional radiography. 11 articles were included in the data synthesis. The study populations of the included studies were varied: patients, image quality phantoms and anatomical phantoms. The clinical applications of X-ray scatter correction software were found to be limited to specific body parts (cervical spine, chest, shoulder, lumbar spine, hip and pelvis). The scatter correction software appears to be effective in terms of image quality and in reducing the radiation dose. However, the conventional grid still provides a higher image quality.
    CONCLUSIONS: X-ray scatter correction software can be effective and provides potentialbenefits for some circumstances or clinical scenarios.
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  • 文章类型: Systematic Review
    光声成像依赖于光学感应声波的检测,为形态和功能成像提供了新的可能性。随着模式向临床应用的成熟,研究工作旨在解决对最终图像质量产生负面影响的多因素限制。为了对局限性及其影响有清晰的认识,以及这个渐进细化过程的现状,我们进行了广泛的搜索光声图像质量改善方法,已经与人类在体内评估,因此重点关注临床相关结果。我们查询六个数据库(PubMed,Scopus,WebofScience,IEEEXplore,ACM数字图书馆,和GoogleScholar)于2010年1月1日至2021年10月31日发表的文章,并通过系统的筛选过程确定了45项相关研究作品。我们回顾了已确定的方法,描述他们的主要目标,有针对性的限制,和关键技术实施细节。此外,将全面和客观的质量评估视为在临床实践中采用此类方法的必要前提,我们对45篇论文中的36篇进行了对报告的质量评估程序的进一步深入分析,并引出一套旨在捕获关键评估方面的标准。通过比较标准的评级过程,我们寻求在对他们提出的方法进行质量评估方面表现出卓越的研究工作,并讨论将它们与具有相似目标的作品区分开的功能。此外,根据评级结果,我们强调有改善潜力的领域,并为设计能够提供丰富证据的质量评估管道提取建议。
    Optoacoustic imaging relies on the detection of optically induced acoustic waves to offer new possibilities in morphological and functional imaging. As the modality matures towards clinical application, research efforts aim to address multifactorial limitations that negatively impact the resulting image quality. In an endeavor to obtain a clear view on the limitations and their effects, as well as the status of this progressive refinement process, we conduct an extensive search for optoacoustic image quality improvement approaches that have been evaluated with humans in vivo, thus focusing on clinically relevant outcomes. We query six databases (PubMed, Scopus, Web of Science, IEEE Xplore, ACM Digital Library, and Google Scholar) for articles published from 1 January 2010 to 31 October 2021, and identify 45 relevant research works through a systematic screening process. We review the identified approaches, describing their primary objectives, targeted limitations, and key technical implementation details. Moreover, considering comprehensive and objective quality assessment as an essential prerequisite for the adoption of such approaches in clinical practice, we subject 36 of the 45 papers to a further in-depth analysis of the reported quality evaluation procedures, and elicit a set of criteria with the intent to capture key evaluation aspects. Through a comparative criteria-wise rating process, we seek research efforts that exhibit excellence in quality assessment of their proposed methods, and discuss features that distinguish them from works with similar objectives. Additionally, informed by the rating results, we highlight areas with improvement potential, and extract recommendations for designing quality assessment pipelines capable of providing rich evidence.
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  • 文章类型: Systematic Review
    UNASSIGNED:计算机图像分析是一种评估图像质量的可行技术,是对人类观察者的补充。
    UNASSIGNED:系统地回顾在使用乳房X线照相术评估2D图像质量中使用的图像分析软件。
    UNASSIGNED:从成立到2020年7月,对多个数据库进行了系统搜索,以获取包含对物理乳房X线照相术的2D图像进行计算机分析以确定图像质量的文章。
    未经评估:共纳入26项研究,12使用直接数字成像进行,14使用屏幕胶片乳房X线照相术进行。ACR体模(156型)是评估最频繁的体模,可能是由于缺乏公认的标准软件。与观察者之间的变化相比,计算机图像分析在对测试对象进行评分时更加一致.发现模板匹配方法是最可靠的算法之一,特别是对于高对比度的测试对象,而一些算法发现低对比度的测试对象很难区分,因为测试对象和它们的背景之间的对比度变化较小。对于小的物体尺寸尤其如此。
    UNASSIGNED:图像分析软件与人类观察者一致,但显示出更高的质量评估一致性和可重复性。此外,使用计算机分析,诸如对比噪声比(CNR)和信噪比(SNR)的几个定量指标可以用来补充传统的评分方法。实施用于随时间监测图像质量的计算机化方法对于在影响临床图像之前检测任何恶化的乳房X线照相术系统至关重要。
    UNASSIGNED: Computerized image analysis is a viable technique for evaluating image quality as a complement to human observers.
    UNASSIGNED: To systematically review the image analysis software used in the assessment of 2D image quality using mammography phantoms.
    UNASSIGNED: A systematic search of multiple databases was performed from inception to July 2020 for articles that incorporated computerized analysis of 2D images of physical mammography phantoms to determine image quality.
    UNASSIGNED: A total of 26 studies were included, 12 were carried out using direct digital imaging and 14 using screen film mammography. The ACR phantom (model-156) was the most frequently evaluated phantom, possibly due to the lack of accepted standard software. In comparison to the inter-observer variations, the computerized image analysis was more consistent in scoring test objects. The template matching method was found to be one of the most reliable algorithms, especially for high-contrast test objects, while several algorithms found low-contrast test objects to be harder to distinguish due to the smaller contrast variations between test objects and their backgrounds. This was particularly true for small object sizes.
    UNASSIGNED: Image analysis software was in agreement with human observers but demonstrated higher consistency and reproducibility of quality evaluation. Additionally, using computerized analysis, several quantitative metrics such as contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) could be used to complement the conventional scoring method. Implementing a computerized approach for monitoring image quality over time would be crucial to detect any deteriorating mammography system before clinical images are impacted.
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  • 文章类型: Journal Article
    In this era of digitization, most hardcopy documents are being transformed into digital formats. In the process of transformation, large quantities of documents are stored and preserved through electronic scanning. These documents are available from various sources such as ancient documentation, old legal records, medical reports, music scores, palm leaf, and reports on security-related issues. In particular, ancient and historical documents are hard to read due to their degradation in terms of low contrast and existence of corrupted artefacts. In recent times, degraded document binarization has been studied widely and several approaches were developed to deal with issues and challenges in document binarization. In this paper, a comprehensive review is conducted on the issues and challenges faced during the image binarization process, followed by insights on various methods used for image binarization. This paper also discusses the advanced methods used for the enhancement of degraded documents that improves the quality of documents during the binarization process. Further discussions are made on the effectiveness and robustness of existing methods, and there is still a scope to develop a hybrid approach that can deal with degraded document binarization more effectively.
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  • 文章类型: Journal Article
    背景:为了首次报告使用Perfect在巴布亚新几内亚(PNG)进行的乳房X线照片的图像质量,很好,中等,不足(PGMI)图像评估系统(IES);并根据澳大利亚BreastScreen(BSA)国家认证标准(NAS)对图像质量进行基准测试。
    方法:使用PGMIIES对在莫尔兹比港综合医院(PMGH)成像的102名女性的去识别乳房X线照片进行回顾性图像质量分析。每个颅尾(CC)和中外侧斜(MLO)图像都被分配了等级,并记录了等级的原因。年龄以年为单位记录。进行了简单的频率分析,并与BSANAS2.4进行了比较。
    结果:女性年龄在25至74岁之间。有111个CC视图和109个MLO视图。CC视图最常见的个人等级是G(83.8%),MLO视图M(72.48%);对于常规系列(四张图像),P和G合计(14.8%)。IMA的非可视化(28%),乳头未轮廓(26%)和胸肌长度短(12%)是指定M级的最多原因。
    结论:报告的图像质量与BSA要求的图像质量不相称(P和G>50%),虽然可以通过教育和培训纠正常见的定位错误,同样重要的是要认识到PNG射线照相师在获得超越教育和培训的乳房X光图像方面所面临的复杂挑战,并反映了模态的新兴性质以及更广泛的健康,经济和其他问题。这项工作提出了国家标准的必要性,专用设备,和摄影师教育,以最好地服务于巴布亚新几内亚的妇女。
    BACKGROUND: To report for the first time the image quality of mammograms performed in Papua New Guinea (PNG) using the Perfect, Good, Moderate, Inadequate (PGMI) image evaluation system (IES); and to benchmark the image quality against BreastScreen Australia (BSA) National Accreditation Standards (NAS).
    METHODS: A retrospective image quality analysis of the de-identified mammograms of 102 women imaged at the Port Moresby General Hospital (PMGH) was undertaken using the PGMI IES. Each craniocaudal (CC) and mediolateral oblique (MLO) image was assigned a grade and the reasons for the grade recorded. Age was recorded in years. Simple frequency analysis was undertaken and comparison with BSA NAS 2.4 was made.
    RESULTS: Women were aged between 25 and 74 years. There were 111 CC views and 109 MLO views. The most frequent individual grade for the CC view was G (83.8%) and for the MLO view M (72.48%); and for a routine series (four images), P and G combined (14.8%). Non-visualisation of the IMA (28%), nipple not in profile (26%) and short length of pectoral muscle (12%) were the most cited reasons for assigning an M grade.
    CONCLUSIONS: The reported image quality is not commensurate with that required by BSA (P and G > 50%) and while common positioning errors can be rectified through education and training, it is also important to recognise the complex challenges faced by PNG radiographers in obtaining mammographic images that extend beyond education and training and reflect the emerging nature of the modality as well as wider health, economic and other issues. This work raises the need for national standards, dedicated equipment, and radiographer education to best serve the women of PNG.
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  • 文章类型: Journal Article
    锥形束计算机断层扫描(CBCT)是一种多样化的3DX射线成像技术,在过去的二十年中在牙科放射学中获得了广泛的普及。CBCT克服了传统二维牙科成像的局限性,能够准确描绘颌面部骨性结构和周围软组织的多平面细节。在这篇评论文章中,我们提供牙科CBCT成像的最新状态,并总结当前使用的CBCT扫描仪模型的技术特征,延伸到扫描仪技术的最新发展,临床方面,以及关于剂量优化的监管观点,剂量测定法,和诊断参考水平。我们还考虑了潜在技术的前景,以及在提供临床上更有效的CBCT检查时应解决的问题,这些检查应针对患者的利益进行优化。
    Cone beam computed tomography (CBCT) is a diverse 3D x-ray imaging technique that has gained significant popularity in dental radiology in the last two decades. CBCT overcomes the limitations of traditional two-dimensional dental imaging and enables accurate depiction of multiplanar details of maxillofacial bony structures and surrounding soft tissues. In this review article, we provide an updated status on dental CBCT imaging and summarise the technical features of currently used CBCT scanner models, extending to recent developments in scanner technology, clinical aspects, and regulatory perspectives on dose optimisation, dosimetry, and diagnostic reference levels. We also consider the outlook of potential techniques along with issues that should be resolved in providing clinically more effective CBCT examinations that are optimised for the benefit of the patient.
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  • 文章类型: Journal Article
    背景:乳房X线照相术是技术要求最高的射线照相过程之一,和乳房X线照相术质量保证举措是实施公共卫生筛查服务的优先事项。在优化图像质量(IQ),放射技师发挥了重要作用。在1998年至2009年之间,意大利北部大型人群筛查服务的乳房X线照相术指导委员会对成像设施进行了几次审核检查。2009年,筛查服务的目标年龄范围得到了扩展。乳房X线照片的体积预计将急剧增加,但放射线照相师的劳动力没有实质性增加。
    方法:鉴于对乳房X线摄影智商的潜在影响,被动审核方法被放弃,转而采用主动的以放射技师为导向的智商审查计划。其技术基础包括由每名一级放射技师和更有经验的本地参考放射技师定期重复进行数字乳房X线照片随机抽样审查,通过智商分类,接下来是培训工作和监控工作。
    结果:乳房X线照片体积从2008年的140,822增加到2014年的319,394(127%),然后稳定下来。2012年,智商差的乳房X光检查的比例从0.6%上升到19.3%,同时乳房X线照片的大幅减少被解释为具有中等和完美的智商。相反,在2016年和2018年的第一轮都出现了普遍的改善.
    结论:在新的挑战性场景中,该方案被证明是有效的。成功的智商审查计划是鼓励放射技师以积极和自信的态度参与的计划。
    BACKGROUND: Mammography is one of the most technically demanding radiographic processes, and mammography quality assurance initiatives are priorities in the implementation of public health screening services. In the optimisation of image quality (IQ), radiographers play a major role. Between 1998 and 2009, the steering committee for mammography of a large population-based screening service in northern Italy undertook several audit checks of the imaging facilities. In 2009, the target age range of the screening service was extended. The mammogram volume was projected to increase steeply but with no substantial increase in the radiographer workforce.
    METHODS: In view of the potential impact on mammographic IQ, the passive audit approach was abandoned in favour of an active radiographer-oriented IQ review programme. Its technical basis consists of regularly repeated rounds of review of random samples of digital mammograms performed by each first-level radiographer and by more experienced local reference radiographers, with IQ classification, followed by a training effort and a monitoring work.
    RESULTS: The mammogram volume grew from 140,822 in 2008 to 319,394 in 2014 (+127%) and then stabilised. In 2012, the proportion of mammograms with a poor IQ rose from 0.6% to 19.3%, paralleled by a substantial decrease of mammograms interpreted to have a moderate and perfect IQ. Conversely, a generalised improvement occurred in both rounds of 2016 and in the first round of 2018.
    CONCLUSIONS: In the new challenging scenario, the programme proved to be effective. A successful IQ review initiative is one that encourages radiographers to participate with a positive and confident attitude.
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  • 文章类型: Journal Article
    The anode heel effect can be used to optimize image quality and/or patient dose in digital radiography (DR). In film-screen radiography, the effect can equalize optical density in regions of varying attenuation. Clinical experience suggests that the implementation of DR has led to less awareness of anode orientation. Post-processing is assumed to compensate, but may also alter image impression and potentially obscure image details. Published evidence was examined for the influence of the anode heel effect on image quality in DR.
    A systematic literature search was carried out using PubMed, Embase, and Web of Science databases. Title and abstracts were screened blinded by three authors, according to in-/exclusion criteria, followed by full-text analysis for final inclusion. Studies where technical and/or visual image quality were reported, was included. All studies were analyzed and assigned quality scores, according to relevant questions. The authors devised a scoring system based on reported information pertaining to reproducibility, interpretation, and generalizability of the methods and conclusions.
    Five studies were included of heterogeneous design, each with methodological shortcomings. Only a few anatomical areas were covered. Very few patients were examined, and in no studies were images evaluated by radiologists or reporting radiographers. Relevant information such as post-processing, image quality criteria and analysis was insufficient in most studies, making reproduction difficult. Results were contradictory, especially concerning technical vs visual image quality.
    Limited published evidence was found quantifying the influence of the anode heel effect on image quality using DR technology. More methodologically, robust studies are needed. The published evidence neither proves nor disproves the impact of the heel effect on image quality in DR.
    Based on a systematic review, no firm recommendations for anode orientation relating to image quality in DR can be provided.
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