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1.
《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects.  相似文献   
2.
对50只正常眼和47只青光眼进行阈值改良Amsler表与Humphrey静态分析仪视野检查比较,两种方法存在着相关关系,阳性检出率无区别,提示阈值改良Amsler表对青光眼早期视野损害有较高的检出率。  相似文献   
3.
BACKGROUND: Patient education is integral part of any diabetes therapy in Germany, but elderly patients are not able to follow the variety of topics comprising standard treatment and teaching programmes (TTP), primarily due to impaired neuropsychological function. This leads to deficits in diabetes knowledge and hindered ability for diabetes self-management. AIM: To evaluate structured TTP for geriatric patients with impaired cognitive function. PATIENTS AND METHODS: A neuropsychological examination was performed on all patients over 54 years [n=102, age 68.6 +/- 8.7 years, diabetes duration 10.3 (0.03-35.4) years, HbA1c 10.3 +/- 1.7% (HPLC, Diamat, NR 4.5-6.3%), cognitive function 87.7 +/- 12.3 IQ points] who took part in TTP for insulin therapy. Patients with impaired cognitive function participated either in the standard TTP of Berger [n = 35, age 67.6 +/- 8.9 years, diabetes duration 9.9 (0.04-35.4) years, HbA1c 10.3 +/- 2.0%] or in the specialized structured geriatric DICOF-TTP [n=33, age 70.4 +/- 8.2 years, diabetes duration 10.4 (0.03-24.9) years, HbA1c 10.7 +/- 1.8%]. RESULTS: After TTP there were no differences in knowledge and ability for diabetes self-management (standard/DICOF: knowledge 11.0 +/- 2.6 vs. 12.2 +/- 2.7 points, P = 0.11; handling 14.9 +/- 3.3 vs. 15.9 +/- 2.5 points, P = 0.18). However, patients who took part in the DICOF programme showed better scores in satisfaction with the education programme [standard/DICOF 44.7 (31-57) vs. 52.5 (45-59) points, P < 0.001]. Six months later the DICOF participants showed better results regarding diabetes self-management (standard/DICOF: handling 12.5 +/- 4.1 vs. 15.9 +/- 3.1 points, P = 0.001). Both groups showed HbA1c decrease (8.3 +/- 1.4 vs. 8.5 +/- 1.3%, P=0.62) and similar incidence of acute complications. CONCLUSIONS: Elderly patients with impaired cognitive function should take part in specialized structured TTP. This leads to both better satisfaction with the education programme and an improved ability for diabetes self-management.  相似文献   
4.
Recently, the digital imaging and communications in medicine (DICOM) standard introduced rules for the encoding, transmission, and storage of the imaging diagnostic report. This medical document can be stored and communicated with the images in picture archiving and communication system (PACS). It is a structured document that contains text with links to other data such as images, waveforms, and spatial or temporal coordinates. Its structure, along with its wide use of coded information, enables the semantic understanding of the data that is essential for the Electronic Healthcare Record deployment. In this article, we present DICOM Structured Report (SR) and discuss its benefits. We show how SR enables efficient radiology workflow, improves patient care, optimizes reimbursement, and enhances the radiology ergonomic working conditions. As structured input significantly alters the interpretation process, understanding all its benefits is necessary to support the change. Biography Rita Noumeir is a professor at the Department of Electrical Engineering of the University of Quebec, école de Technologie Superieure in Montreal. A founding member of the Imaging, Vision, and Artificial Intelligence Laboratory (LIVIA), her main research interest is the Healthcare Information Technology, specifically, Interoperability, Electronic Patient Record, Security, Information Confidentiality, and Image Processing. As a member of both Technical and Planning International IHE Radiology Committees, Dr. Noumeir took part over the last 5 years in developing many Integrating the Healthcare Enterprise (IHE) Integration Profiles in Radiology and in organizing several Integration Demonstrations. She is a cofounder of IHE Canada. Dr. Noumeir contributed to many research and development projects in collaboration with several Canadian and international companies in medical imaging and healthcare information. Currently, she collaborates with the Diagnostic Imaging Team of Canada Health Infoway to define the principles and architecture for sharing imaging information between multiple healthcare institutions. She plays a leading role in the development of this solution that is published as an IHE Integration Profile for which she is the editor. Rita Noumeir holds a Ph.D. and a Masters degree in Biomedical Engineering from école Polytechnique of Montreal specializing in Medical Imaging. She is a professional engineer, and a member of the Ordre des ingénieurs du Québec.  相似文献   
5.
Computed radiography (CR) has many advantages such as filmless operations, efficiency, and convenience. Furthermore, it is easier to integrate with the picture archiving and communication systems. Another important advantage is that CR images generally have a wider dynamic range than conventional screen film. Unfortunately, grid artifacts and moiré pattern artifacts may be present in CR images. These artifacts become a more serious problem when viewing CR images on a computer monitor when a clinic grade monitor is not available. Images produced using a grid with higher frequency or a Potter–Bucky grid (i.e., a moving grid, Bucky for short) can reduce occurrence but cannot guarantee elimination of these artifacts [CR & PACS (2000); Detrick F (2001), pp 7–8]. In this paper, the formation of the artifacts is studied. We show that the grid artifacts occur in a narrow band of frequency in the frequency domain. The frequency can be determined, accurately located, and thus removed from the frequency domain. When comparing the results obtained from the proposed method against the results obtained using previous computer methods, we show that our method can achieve better image quality.  相似文献   
6.
Laboratory of Cytochemistry, Brain Research Institute, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR O. S. Adrianov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 7, pp. 41–42, July, 1991.  相似文献   
7.
Methacholine reactivity and asthma   总被引:1,自引:0,他引:1  
Methacholine tests were used in an epidemiologic study of the prevalence of asthma and chronic bronchitis in northern Sweden. Of 6610 subjects in three age groups from eight representative geographic areas in the northernmost province of Sweden, 5698 (86%) completed a postal questionnaire on respiratory symptoms, and 1506 underwent a structured interview and a lung function test. A total of 292 (5%) were diagnosed as having asthma. A subsample of 284 subjects (of 320 invited) classified at the interview as having asthma ( n = 98) or as having respiratory symptoms that might be due to asthma but not fulfilling the interview criteria for the diagnosis of asthma ( n = 186) underwent a methacholine test. Subjects who, before the interview study, already had a well-defined asthma diagnosis were not invited to the methacholine testing. Of those 98 subjects classified as having asthma, 61 % reacted to methacholine doses ≤ 4 mg/ml and 79% to doses ≤ 8 mg/ml, while the corresponding figures in the symptomatic but nonasthma group were 20% and 34%, respectively. The results show that a carefully performed structured interview accurately diagnoses asthma in epidemiologic studies. The methacholine tests provide important diagnostic information primarily in subjects in whom the medical history is equivocal.  相似文献   
8.
Background One of the most important requirements for contemporary education of a health care professional is to develop a framework for theory and practise which results in attainment of professional competencies suitably robust for a lifetime of practise ( Howe, 2002 ). In the context of those educating preregistration dietitians, this offers the challenge of presenting the student with innovative curricula designed to deliver the appropriate level of knowledge and understanding together with emphasis on skill and attitude development. The purpose of this study was to allow preregistration students the opportunity to practise key clinical skills prior to clinical placement and test skills acquisition using the model of an objective structured clinical examination (OSCE). Methods The learning experience of the student was altered to accommodate a more conceptually‐driven, problem‐centred, case‐based approach. The curriculum was adjusted to incorporate a short clinical skills programme where emphasis was deliberately placed on skill acquisition. At the conclusion of this clinical skills programme, and prior to the students entering clinical placement, skill performance by students was tested using the OSCE. The method of testing was also evaluated by students. Results The OSCE was delivered to 37 preclinical students. Four of the test candidates (11%) failed in at least one of the skill areas: these students performed similarly during clinical placement. Twenty‐one (57%) students returned the post‐OSCE questionnaire. Twenty (95%) students reported a positive experience; 20 (95%) students reported initial anxiety that diminished as the test progressed. Conclusion The Project Team was confident with the novel approach taken in re‐designing the curriculum: to include a dedicated clinical skills programme, together with addition of the testing of clinical skills using the OSCE model. These curriculum changes were deemed to be highly appropriate additions to the student experience in determination of skill performance of students prior to clinical placement.  相似文献   
9.
【目的】观察结构化教育治疗儿童孤独症的疗效,为临床治疗提供参考依据。【方法】对32例儿童孤独症患儿进行评估后,制定个别化教育计划。训练中应用结构化教育模式,将视觉线索应用到各个活动场所,强调作息时间和教学环境的结构化,强调工作组织的结构化。每周5 d,每天6 h,共训练6个月。用孤独症治疗评估量表(AutismTreatment Evaluation Checklist,ATEC)及C-PEP进行疗效评估。【结果】32例患儿孤独症儿童量表平均总分由训练前的(96.09±18.95)分下降到(54.91±14.10)分(P<0.001),量表中言语、社交、感知觉、行为四个分项目得分显著下降(P<0.001)。C-PEP评估功能发展平均分值由训练前(28.00±11.08)提高到(48.00±11.27),年龄当量提高(9.00±5.32)个月,扣除生理增长6个月,实际年龄当量增长(3.00±5.32)个月。【结论】结构化教育治疗对孤独症是一有效的训练方法。  相似文献   
10.
浅谈结构化综合布线系统的设计   总被引:3,自引:3,他引:3  
结构化综合布线系统是一种包含着多种先进技术的高技术系统,是一种内容极其丰富的复合结构和功能广泛的计算机管理系统,是一种提供各种服务项目的公共服务系统,还是一种需要专业人员安装、管理、维护的专业系统。结构化综合布线系统是医院管理信息系统的通用平台,是向所有具有通信要求的设备提供通信线路的最底层的系统,布线系统的先进性、灵活性和可扩充性将极大地影响整个医院管理信息系统的先进性、灵活性和扩充能力,应事先将不确定因素考虑在内,使布线系统可以满足用户不断发展的需求,而布线系统的性能在很大程度上受到设计质量的影响。  相似文献   
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