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51.
基于PACS的MRI影像多媒体教学与报告系统的研究 总被引:5,自引:0,他引:5
目的:开发基于医院影像归档和通讯系统(picture archiving and communication system,PACS)环境的MRI(磁共振显像)影像多媒体教学与报告系统。方法:医院PACS系统符合DICOM3.0标准,采用1000M光纤主干网,100M交换到桌面;在临床医生浏览工作站安装多媒体教学系统,在诊断工作站安装教学系统与报告系统;科学内容按部位分类,以树枝模式管理。教学字资料来源于具有一定权威的教科书、专及期刊。图像资料来源于各部位经病理及临床证实的病例,直接从PACS系统提取,经标注说明后,以件形式存放于PACS图像服务器硬盘。结果:MRI辅助影响教学系统能够实时调阅最合适病种的MRI征象、临床特点、病理、鉴别诊断、典型图像及注释、正常断面解剖等,供教学、诊断和报告参考。结论:PACS环境下MRI辅助影像学系统,能满足临床医生和低年资影像诊断医生对MRI影像知识进一步继续医学教育的需求,能为影像诊断医生提供教学及科研工具,提高MR室工作质量和工作效率。 相似文献
52.
C. Sorlié O. Bertrand B. Yvert J. -C. Froment J. Pernier 《Medical & biological engineering & computing》1997,35(3):239-245
A method has been developed to match a standard digitised brain atlas onto MR images for identification of cerebral structures
in anatomical images. This method uses, first, a three-dimensional crude registration based on the proportional system of
Talairach. Then, a two-dimensional refined registration is performed using a deformation function based on a set of homologous
landmarks on both images (MR and atlas). Displacements vectors are computed between each corresponding landmark. These vectors
are interpolated by thin-plate splines, generating an unwarping function defined on the whole image. This function can then
be applied on any structure of the atlas. An evaluation of the matching procedure has been performed. First, the influence
of the choice of the landmarks has been evaluated for the fine registration method. The latter has been then compared to the
crude registration method considered as a classical reference method. These results show the advantages of the fine registration
approach. 相似文献
53.
Cross-platform development of medical applications in extended-reality (XR) head-mounted displays (HMDs) often relies on game engines with rendering capabilities currently not standardized in the context of medical visualizations. Many aspects of the visualization pipeline including the characterization of color have yet to be consistently defined across rendering models and platforms. We examined the transfer of color properties from digital objects, through the rendering and image processing steps, to the RGB values sent to the display device. Five rendering pipeline configurations within the Unity engine were evaluated using 24 digital color patches. In the second experiment, the same configurations were evaluated with a tissue slide sample image. Measurements of the change in color associated with each configuration were characterized using the CIE 1976 color difference (). We found that the distribution of for the first experiment ranges from zero, as in the case using an Unlit Shader, to 25.97, as in the case using default configurations. The default Unity configuration consistently returned the highest across all 24 colors and also the largest range of color differences. In the second experiment, E ranged from 7.49 to 34.18. The Unlit configuration resulted in the highest in three of four selected pixels in the tissue sample image. Changes in color image properties associated with texture import settings were then evaluated in a third experiment using the TG18-QC test pattern. Differences in pixel values were found in all nine of the investigated texture import settings. The findings provide an initial characterization of color transfer and a basis for future work on standardization, consistency, and optimization of color in medical XR applications. 相似文献
54.
Standardization for image characteristics in telemammography using genetic and nonlinear algorithms 总被引:2,自引:0,他引:2
As the soft copy reading and computer assisted diagnosis (CAD) in mammography become more and more important, the standardization of digital images becomes paramount. Telemammography and telemedicine requires the standardization for image characteristics, such as image resolution, bit-depth and intensity response. Soft copy reading and CAD in mammography are both dependent on the characteristics of the source of the digital data, either direct digital mammography or digitized screen-film mammography. An algorithm developed on images from one database may not perform well as on images from another database (with a different digitization). In this paper, we describe two methods based on a genetic algorithm and a nonlinear algorithm for standardization of digitized and digital mammography. The proposed standardization techniques are based on geometric and intensity transformations that are discovered using a set of calibration images. A set of transformation algorithm is used to search for the best standardization. 相似文献
55.
Automatic identification of landmarks in cephalometry is very important and useful for orthognathic surgery. A computerised
automatic cephalometric analysis system (CACAS), based on image processing, is presented. For an original X-ray image, median
filtering and histogram equalisation are used to improve image quality. The edge of an X-ray image is detected by a wavelet
transform and Canny filter. Seventeen landmarks in cephalometry are successfully identified by knowledge-based edge tracing
and changeable templates. Seventy-three measurements based on distances, angles and ratios between landmarks are computed
automatically. The reliability of the landmarks and the validity of the measurements are compared for automatic and manual
operation. The values of measurements obtained by CACAS are more precise and reliable: the mean error for linear measurements
is less than 0.9 mm; the mean error for angular measurements is less than 1.2°. The rate of validity is over 80%, even if
the image quality is poor. For an image with a high signal-to-noise ratio, the rate of validity of landmarking and measurements
using the CACAS system is over 90%. 相似文献
56.
目的为了方便快捷地实时监测心律失常,设计一种基于PDA的嵌入式ECG监护分析仪。方法仪器功能包括低功耗MSP430系列单片机控制心电信号的采集、放大、滤波、转换和在PDA上实时显示、存储和分析,并实现心电数据的远程传输。对仪器工作原理进行分析,把监护分析仪总体结构划分为子模块,并具体介绍各子模块的功能与实现。结果与结论与医院现有的三导全自动心电图机、Holter动态心电图机进行对照,本监护分析仪携带方便、操作简单、接收的心电信号无失真,连续工作时间大于20h等。各高频干扰信号对ECG信号无影响;软件可对心电信号进行实时显示,可连续记录15h的原始心电数据。 相似文献
57.
Anabelle T. Visperas Kenneth A. Greene Viktor E. Krebs Alison K. Klika Nicolas S. Piuzzi Carlos A. Higuera-Rueda 《The Journal of arthroplasty》2021,36(7):2290-2296.e1
BackgroundWeb-based platforms used to enhance patient-provider communication are being explored to improve patient satisfaction and care delivery, and decrease cost. This study tested a web-based interactive patient-provider software platform (IPSP), JointCOACH, which enabled patient communication with their care team and preparatory/recovery guidance. The aims of this study are to compare (1) patient satisfaction and (2) healthcare resource utilization by patients who underwent total knee and hip replacements and added IPSP to standard of care (SOC).MethodsThis study is a prospective, randomized clinical trial at a single large academic healthcare system. Between May 2018 and March 2020, 399 patients undergoing elective total hip or knee arthroplasty were randomized to SOC arm (n = 204) or SOC + IPSP arm (n = 195). Patient demographics, surgical details, and comorbidities were collected. Patient satisfaction was assessed using Visual Analog Scale and the Picker Patient Experience-15. Healthcare utilization was measured using length of stay, emergency department and office visits, office calls, readmissions, and reoperations at 30 and 90 days after surgery.ResultsNo difference was found in length of stay between SOC and SOC + IPSP. No differences were found in 30-day or 90-day satisfaction or in healthcare resource utilization (P > .05) including number of office and emergency department visits, phone calls, and readmissions.ConclusionStatistical differences were not found in satisfaction and healthcare utilization with the addition of IPSP to SOC. IPSP can be used to reinforce patient education and communication between the patient and provider, and should be evaluated as an element of virtual care rather than supplementing traditional in-office follow-up.Clinicaltrials.govMore information on this study can be found at clinicaltrials.gov NCT03499028. 相似文献
58.
59.
目的本文介绍了结核病管理软件管理系统的结构组成、功能和主要技术,使用意义。材料与方法:以WINDOWS为开发平台,用VFOXPRO6。0设计出用于结核病管理的应用软件。结果:该软件可用于病人登记、查询、统计、统计分析以及管理。结论:用微机进行结核病人管理具有重要意义。 相似文献
60.
Iterative reconstruction algorithms 总被引:7,自引:0,他引:7
In this paper a survey of recent results on iterative reconstruction algorithms is given. These results, many of which have not yet appeared elsewhere, are applicable to a very general formulation of the reconstruction problem based on the series expansion approach. A set of optimization criteria and a number of iterative reconstruction algorithms are stated, together with theorems on the convergence of the algorithms to optimum images. The efficacy of the algorithms is compared to that of the convolution method. In particular, the falseness of the claim that ART and the backprojection method are the same is demonstrated. 相似文献