浅析PACS中的DICOM标准

随着医学影像设备的广泛应用以及PACS的快速发展,为了统一各种数字化影像设备的图像数据格式和数据传输标准而诞生的DICOM标准已经成为医学数字成像和通讯的共同标准。本文简要的介绍了DICOM标准的历史以及DICOM数据集和DICOM文件格式的组织形式。     

Digital Imaging and Communications in Medicine (DICOM) information conversion procedure for SUV calculation of PET scanners with different DICOM header information

PurposeIn nuclear medicine, the standardized uptake value (SUV) obtained using positron emission tomography with 2-deoxy-2-fluoro-D-glucose (FDG-PET) is widely used as a semi-quantitative diagnosis factor. We found that the header file of the Philips Allegro PET scanner using the Digital Imaging and Communications in Medicine (DICOM) standard was stored differently than with other scanners. Thus, the purpose of this study was to develop a DICOM header information conversion program to ensure compatibility between Allegro and other equipment.Methods and resultsThe NEMA IEC Body phantom was scanned using the Allegro PET scanner. We conducted measurements and performed calculations by using commercial software and the proposed self-developed program, respectively, to compare the SUVs by using conversion data. The program consists of three parts: an input part that can load data regardless of the number of DICOM images, and conversion and output parts that can be used to convert the DICOM header information and store it in the order of slices. The results of the calculation are in good agreement with the data measured at 12 circular regions of interest. The percent difference was lower than the 20%.ConclusionIn conclusion, this study suggested a simple and convenient method to solve the incompatibility through conversion of the DICOM header information. This study thus provides physicians more accurate information for diagnosis and treatment.     

基于VT K 的D IC OM 医学图像三维重建研究

医学图像三维重建技术利用二维医学图像序列重建出三维模型,为医生提供直观、全面、准确的病灶和正常组织信息．是当今医学影像领域研究的热点之一。VTK是国际上广泛应用的可视化工具包,具有优秀的架构和运行机制。本文研究了DICOM3．0标准,提出了正确解读DICOM医学图像的方法;深入VTK内部机制,解决了VTK和DICOM医学图像读取模块间的数据接口问题;在三维重建过程中,为解决数据量巨大、成像时间漫长、阶梯效应、交互性不强等问题,重点剖析了VTK的数据处理机制。并给出相关优化方法。实验结果表明本文提出的解决方案和优化方法实用可靠,为进一步开发医学三雏图形系统打下了基础。     

Development of a universal interface for the exchange of medical image data using magneto-optical media]

Digital images generated by medical imaging form the basis for radiological diagnosis and surgical planning. Despite the advent of the DICOM 3.0 standard for medical image communication, widespread application of the existing information is often limited by incompatibility of the data formatting used by different equipment generations, and the manufacturer-specific standards employed. An exchange interface based on magneto optical discs has been developed to retrieve and present medical image data regardless of the technological hardware and the specific formats used. Specially adapted routines to retrieve the data first had to be developed. A modular program structure was used to allow flexibility in the implementation of further routines and other exchange media. Over 20,000 CT and MRI images including header information obtained from different General Electric and Siemens scanners were extracted successfully from MO discs. The image data were used for follow up and surgical planning and were transferred to a PAC-server. The interface proved reliable and easy to use. Support for further proprietary formats is currently being developed. The present exchange interface permits reliable retrieval of digital images for diagnostic and surgical planning purposes, regardless of the hardware generation and manufacturer-specific formats.     

基于Visual C#语言的DICOM标准医学图像的显示和实现

介绍DICOM3.0医学图像文件的格式和C#语言的特点,首次利用Visual C#语言对该标准的图像进行显示和处理,能够直接读取DICOM格式原始图像数据,并可批量转换成BMP等格式进行处理,此项工作可为医学图像处理研究及相关医学图像软件开发奠定基础。     

A methodology to generate structured computational grids from DICOM data: application to a patient-specific abdominal aortic aneurysm (AAA) model

This study presents the generation of a multi-block structured grid on a real abdominal aortic aneurysm (AAA) acquired from Digital Imaging and Communication in Medicine (DICOM) data. With the use of a computed tomography exam (or medical images in standard DICOM format), the shape of a human organ is extracted and a structured computational grid is created. The structured grid generation is done by utilising Floater's and Gopalsamy et al.'s algorithm. The proposed methodology is applied to the AAA case, but it may also be applied to other human organs, enabling the scientist to develop an advanced patient-specific model. More importantly, the proposed methodology provides a precise reconstruction of the human organs, which is required in an AAA, where small variations in the geometry may alter the flow field, the stresses exerted on the walls and finally the rupture risk of the aneurysm.     

新医改背景下医疗设备信息化管理存在的问题及解决对策探究

医疗设备是医院的重要资产,可在一定程度上反映医院的诊断能力以及现代化程度。新医改政策出台后,各地均大力推进医药卫生信息化建设,随着医疗设备种类的增加,给医院设备管理带来一定的困难,医疗设备信息化管理已成为医院不可或缺的一部分。我国的医疗设备信息化管理起步较晚,尚处于初级研究阶段,从而导致现阶段医疗设备信息化管理问题较多。本文简短叙述了医疗设备信息化管理现状,以及当前医疗设备信息化管理所存在的问题,并对所描述问题提出针对性的解决方案。     

数字减影血管造影设备的维护与维修

数字减影血管造影设备是大型医学影像仪器,在临床诊断及治疗发挥着重要的作用。因此,及时的维护和规范的保养是降低设备故障,减少维修成本,提高工作效率的关键。本文对我院数字减影血管造影设备的保养工作展开回顾,分析临床工作中常见的设备故障,并总结实用的维护、保养方法,为有效利用设备资源提供参考。     

郑州市第五人民医院PACS医学影像系统设计

本文介绍了郑州市第五人民医院PACS医学影像系统,描述了系统的目标,构架,功能和特点,采用了功能化的模块设计。可满足后续设备联入系统,已应用于医院的医疗过程中,解决了医学图像的获取,显示,存储,传输和管理等问题。符合DICOM3.0国际信息交换标准,实现了数字化,网络化和无胶片化的现代化医学影像诊断与管理,显著提高了诊疗质量和工作效率,降低了医疗成本,增加了经济收入和社会效益,对其它医院实现数字化进程也具有一定的借鉴意义。     

DICOM: key concepts--part I

In this issue and next, we're investigating different sections of the DICOM Standard to get a grip on what it's all about. The bottom line is to facilitate communication and DICOM addresses all the technical aspects to allow complying OEMs to talk to one another. In part 2, IT World completes its overview on DICOM by exploring UID, networking with DICOM, conformance, and conformance statements.     

Medical and non-medical protection standards for ultrasound and infrasound

Protection from inappropriate or hazardous exposure to ultrasound is controlled through international standards and national regulations. IEC standard 60601 part 1 establishes requirements for the mechanical, electrical, chemical and thermal safety for all electro-medical equipment. The associated part 2 standard for diagnostic medical ultrasonic equipment sets no upper limits on ultrasonic exposure. Instead, safety indices are defined that are intended to advise users on the degree of thermal and mechanical hazard. At present the display of these safety indices satisfies regulatory requirements in both the USA and Europe. Nevertheless there are reservations about the effectiveness of this approach to protection management. In the USA, there are national regulatory limits on diagnostic exposure, based on acoustic output from clinical equipment in use over 20 years ago. The IEC 60601 part 2 standard for therapeutic equipment sets 3 W cm⁻² as the limit on acoustic intensity. Transducer surface temperature is controlled for both diagnostic and therapy devices.

For airborne ultrasound, interim guidelines on limits of human exposure published by the IRPA are now 2 decades old. A limit on sound pressure level of 100 dB for the general population is recommended. The absence of protection standards for infrasound relates to difficulties in measurement at these low frequencies.     

DICOM-RT Ion interface to utilize MC simulations in routine clinical workflow for proton pencil beam radiotherapy

To adopt Monte Carlo (MC) simulations as an independent dose calculation method for proton pencil beam radiotherapy, an interface that converts the plan information in DICOM format into MC components such as geometries and beam source is a crucial element. For this purpose, a DICOM-RT Ion interface (https://github.com/topasmc/dicom-interface) has been developed and integrated into the TOPAS MC code to perform such conversions on-the-fly. DICOM-RT objects utilized in this interface include Ion Plan (RTIP), Ion Beams Treatment Record (RTIBTR), CT image, and Dose. Beamline geometries, gantry and patient coordinate systems, and fluence maps are determined from RTIP and/or RTIBTR. In this interface, DICOM information is processed and delivered to a MC engine in two steps. A MC model, which consists of beamline geometries and beam source, to represent a treatment machine is created by a DICOM parser of the interface. The complexities from different DICOM types, various beamline configurations and source models are handled in this step. Next, geometry information and beam source are transferred to TOPAS on-the-fly via the developed TOPAS extensions. This interface with two treatment machines was successfully deployed into our automated MC workflow which provides simulated dose and LET distributions in a patient or a water phantom automatically when a new plan is identified. The developed interface provides novel features such as handling multiple treatment systems based on different DICOM types, DICOM conversions on-the-fly, and flexible sampling methods that significantly reduce the burden of handling DICOM based plan or treatment record information for MC simulations.     

Product liability aspects of bioengineering

The introduction of the Consumer Protection Act 1987 brought the problems of product liability directly into hospital bioengineering and medical physics departments. This law makes great demands upon manufacturers, but also on suppliers and maintainers of medical equipment. Departments which manage medical equipment carry a responsibility for ensuring the requirements of product liability are known by all those whose actions may affect the potential of a piece of equipment to injure or damage a patient. This paper addresses these problems from a bioengineering, rather than a legal, viewpoint. The problems of design, manufacture, modification, maintenance and use are discussed and examples of potential problems are identified. The paper concludes that as long as good standards of quality control and professionalism are applied in bioengineering and medical physics departments then there is little to be feared from this piece of legislation.     

基于人机交互的红外探测式智能导盲装置设计

本文介绍了人机交互技术的基本概念和将其应用于导盲装置设计中的病理生理学依据。通过分析盲人的切身需求,结合对常见导盲装置的类型优缺点的比较,提出了一种基于人机交互技术的新型智能导盲装置的设计思路,即应用以红外传感技术为主的多传感器信息融合来进行障碍物探测的,并通过微处理器对探测结果的智能化判断和处理,实现对整个装置行进方向的控制,进而达到引导盲人的作用。文章还阐述了该导盲装置的探测方式、控制功能、指令定义、程序设计和调式改进方面的原理和过程,并展望了其应用和发展前景。     

A perspective of synthetic biology: assembling building blocks for novel functions

Synthetic biology is a recently emerging field that applies engineering formalisms to design and construct new biological parts, devices, and systems for novel functions or life forms that do not exist in nature. Synthetic biology relies on and shares tools from genetic engineering, bioengineering, systems biology and many other engineering disciplines. It is also different from these subjects, in both insights and approach. Applications of synthetic biology have great potential for novel contributions to established fields and for offering opportunities to answer fundamentally new biological questions. This article does not aim at a thorough survey of the literature and detailing progress in all different directions. Instead, it is intended to communicate a way of thinking for synthetic biology in which basic functional elements are defined and assembled into living systems or biomaterials with new properties and behaviors. Four major application areas with a common theme are discussed and a procedure (or "protocol") for a standard synthetic biology work is suggested.     

Bioethics for clinicians: 7. Truth telling

The standard of professional candour with patients has undergone a significant change over the past 30 years. Independent of their obligation to disclose information necessary for informed consent, physicians are increasingly expected to communicate important information to patients that is not immediately related to treatment decisions. The purpose of truth telling is not simply to enable patients to make informed choices about health care and other aspects of their lives but also to inform them about their situation. Truth telling fosters trust in the medical profession and rests on the respect owed to patients as persons. It also prevents harm, as patients who are uninformed about their situation may fail to get medical help when they should.     

Quantitative comparison of freeware software for bone mesh from DICOM files

Musculo-skeletal modelling, 3D printing of bone models and also custom design of relevant prostheses starts from accurate STL files. These are obtained from medical imaging after careful segmentation and 3D reconstruction using specialized software, but most of these are very expensive. The aim of the present study is to assess and compare alternative software available for free. Three freeware software were selected from the most popular, and one standard platform was made available at the institute of the authors. Using each of these four software and starting from available DICOM files obtained previously by a CT scanner, three different bone models were reconstructed from each of five different human anatomical areas for a total of 60 bone model reconstructions. A young radiographer performed the bone reconstruction without specific technical training. 3D spatial matching of corresponding anatomical models was also performed to determine distance-maps for the assessment of final surface quality. In all four software many valuable features were available, with minimum differences, and bone models of good quality were obtained. Large differences in file sizes (mean range over the five anatomical models 66-338) and in the number of triangles (870-1350 thousands) were found, with triangles for MByte ratio ranging from about 4 to 20 thousands. The distance-map analysis revealed that root mean square deviation averaged over the five anatomical models ranged from 0.13 to 2.21 mm for the six spatial matches between the four software. These software are suitable for 3D bone model reconstruction, and do not require special training, and as such these can open up opportunities for biomechanical modelling and medical education.     

A review: taking the sterile out of sterility

Users of in-dwelling medical devices, prostheses and surgical dressings rely implicitly on their sterility. Rarely do consumers give any thought to what sterility really means. The general assumption is that manufacturers have adopted the most efficient and cost-effective methods of achieving sterility. Currently, terminal sterilization processes appropriate for the manufacture of medical devices are those that are deemed to give less than one chance in a million of a single, finished product item containing a viable organism. Such a definition of sterility is embodied in the European standard EN556 as a Sterility Assurance Level of 10(-6), based on the properties of heat-resistant endospores. However, is this level of sterility assurance appropriate for all categories of medical device? Moreover, do all medical devices which are labelled as sterile require the same level of treatment? This paper will demonstrate that in some instances, the high standards set for sterilization processing are unreasonable, not cost-effective and exclude new sterilization technologies from being accepted by the regulatory authorities.     

常用医学图像“局部显微镜”程序的研究

在医学临床和科学研究中,常常需要将图像的某个感兴趣区域(ROI)进行放大显示,以便清晰地观察图像的细节.为了实现这一目标,采用IDL语言(Interactive Data Language)编写了应用程序,从而实现了医学图像“局部显微镜”的功能.一系列实验表明:对于各种常用的医学图像类型(灰度图像、RGB图像、DICOM图像等),程序均能较好地实现放大显示的功能.此外,该程序还具有人机交互性强、可移植性高等优点.