BS-8440-1-2005.pdf

BRITISH STANDARD BS 8440-1:2005 Health informatics Medical digital imaging Profiles format Part 1: General principles ICS 35.240.80 ? Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 26 August 2005 © BSI 26 August 2005 The following BSI references relate to the work on this standard: Committee reference IST/35 Draft for Development 03/107678 DC ISBN 0 580 46549 7 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee IST/35, Health informatics, upon which the following bodies were represented: Association of Anaesthetists of Great Britain and Ireland British Computer Society British Institute of Radiology British Medical Association BUPA Health Level Seven (HL7) Institute of Physics and Engineering in Medicine NHS Connecting for Health Royal College of Radiologists Royal Pharmaceutical Society of Great Britain Amendments issued since publication Amd. No.DateComments Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 © BSI 26 August 2005 i Contents Page Committees responsibleInside front cover Forewordii Introduction1 1Scope 2 2Terms and definitions 2 3MDI profile standards 4 4Framework of the taxonomy of MDI profiles 5 5Structure of MDI profile standards 6 Bibliography 8 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 ii © BSI 26 August 2005 Foreword This British Standard has been prepared by Technical Committee IST/35. Many applications in medical imaging are based on de facto standards and specifications (not published by a standards body) as well as International, European and National Standards. Profiles are needed to achieve the required levels of interoperability in many cases due to the presence of optional provision within the MDI standard or specification. BS 8440 is intended for use in drafting medical digital imaging (MDI) profile standards. This part of BS 8440 is related, but not equivalent in technical content to, BS ISO/IEC TR 10000-1:1995, the content of which has been adapted and extended here to apply to medical digital imaging standards in place of OSI standards. BS 8440, Health informatics Medical digital imaging Profiles format consists of two parts: Part 1: General principles; Part 2: Particular requirements for metadata profiles. Subsequent parts are anticipated. In addition to BS 8440, the secretariat of the BSI/IST/35/-/IV Special Group on MDI Profiles (SGMDIPs) maintains a regularly updated standing document (SD-4), entitled “Directory of medical digital imaging profiles”. This is a record of MDI Profile standards that exist, or are in preparation, together with an executive summary of each profile. This British Standard does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to ii, pages 1 to 8, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 © BSI 26 August 2005 1 Introduction Overview The context of medical digital imaging standardization is one part of the overall field of Information Technology standardization activities covering the following: Medical digital imaging (MDI) standards specify generic data communication procedures and data items. These can be used by systems in a variety of MDI scenarios. Each system can make its own selection from the optional provisions included in standards; Profiles define subsets of MDI standards used to support specific MDI scenarios. Profiles identify the use of particular options available in MDI standards, and provide a basis for the development of recognized conformance tests; Registration mechanisms, which provide the means to record profile standards. The process of MDI standardization is concerned with development of base standard provisions and the specification of profiles, and their publication as profile standards. MDI profile standard. The objective is to facilitate the specification of interoperable IT systems. Interoperability and MDI CR 14300 defines interoperability as: “A state which exists between two application entities, with regard to a specific task, when one application entity can accept data from the other and perform that task in an appropriate and satisfactory manner without the need for extra operator intervention.” Many healthcare scenarios involve the use of digital images as discussed and illustrated in CR 14300. Any given scenario necessitates certain specific functionality necessitating the use of certain specific descriptive data elements. For example, the CEN DICOM Standard provides a rich set of services and optional descriptive data elements to support many medical digital imaging scenarios. Since different suppliers implement different sub-sets of DICOM optional descriptive data elements, interoperability problems can arise. In the case of the DICOM standard a profile consists of a selected sub-set of descriptive data elements and the range of acceptable values that they may hold. Such a profile is often called a metadata profile. The UK panel IST/35/-/IV Medical Informatics: Technology for Interoperability has identified the need for profiles of certain standards and specifications to facilitate the purchase of equipment that fulfils user requirements. Relevant stakeholder bodies will play a key role in the development of appropriate scenarios and use cases concerning healthcare tasks that involve the use of medical image and associated data. The main medical digital imaging data procedures include: production (acquisition and processing), communication, management, and presentation. Medical image data comprise the digital image matrix data values and digital image descriptive data (metadata), and may include digital image rendering data. The amount and nature of the required descriptive data depends on the task that is to be performed using the medical digital image data matrix values. Medical digital imaging involves image data production by acquisition or processing of previously created image data, management, communication and image data rendering to produce a visible image. Medical digital imaging profiles may comprise a data communication part, a descriptive data part or both. An MDI profile has two parts; first, the description of the function that the medical digital imaging profile is intended to enable and secondly, in the case of metadata profiles, the format of the set of data elements that constitute the medical digital imaging profile itself when recorded in printed and electronic form or, in the case of a data communication profile, the record of the medical digital imaging standard provisions that constitute the profile. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 2 © BSI 26 August 2005 Three entities can be identified within the domain of medical digital imaging profiling: a) a medical digital imaging profile; b) the specification of the way to record a medical digital imaging profile standard including the profile and the description of the purpose, supported by MDI scenarios, for which it has been produced; c) an instance of a medical digital imaging profile standard. The availability of appropriate profile standards allows purchasers of systems to specify required functionalities more precisely; therefore easing interoperability between existing, future and newly procured systems. 1 Scope This part of BS 8440 defines the concept of a medical digital imaging profile and the way in which a medical digital imaging (MDI) profile can be documented in an MDI profile standard. It provides principles and outlines a taxonomy for MDI profiles submitted for ratification as MDI profile standard standards. This part of BS 8440 is not concerned with the content of an individual MDI profile. NOTE 1 The existence of a profile classification in this part of BS 8440 does not reflect a judgement by the BSI/IST/35/-/IV Special Group for Medical Digital Imaging Profiles (SGMDIP) that a profile is needed to support any specific functionality. It merely provides a capability to identify uniquely such a profile and to enable evaluation of MDI profile standards. NOTE 2 Since profiles are to be proposed according to needs identified to the SGMDIP and according to the progress of international MDI standardization, the taxonomy is to be periodically updated or have new parts added in order to reflect the progress made. It is also recognized that there will be proposals for the extension of the taxonomy to cover functions which were not identified during the preparation of this standard. These extensions might be identified by a variety of proposers and involve simple extensions to the existing taxonomy or the addition of new functional areas not currently covered. The inclusion of such extensions is administered by following the procedures elaborated by the SGMDIP. 2 Terms and definitions For the purposes of this British Standard, the following terms and definitions apply. 2.1 digital image matrix data matrix of numerical values which can be meaningfully rendered as a visible image by means of an algorithm that maps between the matrix value and the displayed pixel values 2.2 digital image data set of numerical values which can be meaningfully rendered as a visible image and associated digital image descriptive data 2.3 digital image descriptive data data giving information about a digital image matrix, such as a name, a unique identifier, and date of creation NOTE These data are sometimes referred to as metadata. 2.4 digital image image rendered using a set of numerical values 2.5 image visual representation of a real world entity Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 © BSI 26 August 2005 3 2.6 interoperability state that exists when one application entity can accept data from another and perform an intended task in an appropriate and satisfactory manner without the need for extra operator intervention BS 8421-1 formalized from CR 14300 NOTE 1 Interoperability can be expected only with respect to a specific task and for data communication between two known application entities. NOTE 2 Interoperability of systems can be achieved only when clear definitions have been created of the tasks that are to be performed by those systems. 2.7 logical data structure conceptual aspect of data type expressing the nature of values that are composite, i.e. not atoms NOTE An atom is a value that cannot be decomposed. Non-atomic values have constituent parts (which need not themselves be atoms), and the data structure expresses how constituents may be combined to form a compound value or selected from a compound value. 2.8 medical digital image digital image obtained in medicine 2.9 MDI profile subset of the provisions of a medical digital imaging standard NOTE An individual MDI profile might be an image data communication profile or a digital image descriptive data (metadata) profile for the purpose of identifying features that enable a particular function. 2.10 MDI profile taxonomy classification scheme for MDI profiles used for constructing multiple element names for MDI profiles 2.11 MDI standard national or international standard approved for use in the domain of medical digital imaging 2.12 MDI scenario context within which an MDI process takes place 2.13 MDI profile standard document, published under the authority of an appropriate standards committee and approved by a relevant medical digital imaging stakeholder body, which defines an MDI profile and the details of the functions that are enabled by the MDI profile, illustrated with appropriate MDI scenarios and diagrams NOTE The specific data format to be used for expressing an MDI profile standard is presently specified by BS 0-3 (which is to be superseded by a revised BS 0-2 presently in preparation), with additional requirements specified by BS 8440-2. 2.14 product conformance statement (PCS) statement made by the supplier claiming conformance with a specification for a product Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 00:58:21 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8440-1:2005 4 © BSI 26 August 2005 3 MDI profile standards 3.1 Purpose of MDI profile standards MDI profiles are defined for the purposes of: providing a scheme for referencing various uses of MDI standards and MDI profiles which is meaningful to both purchasers and suppliers created in response to a systematic identification and analysis of user requirements; providing a means to enhance the availability for procurement of consistent implementation of functionally defined groups of MDI standards and MDI profiles; and promoting uniformity in the development of conformance tests for MDI systems that implement the functions associated with the MDI profiles. Underlying all these purposes is the assumption that there exists a need for the testing of products which claim conformance to an MDI profile. For a data sending application conformance testing for a metadata profile consists in determining that the application does indeed communicate the required information (i.e. all required data items are communicated carrying the required semantics). For a receiving application, conformance consists in determining that: a) the data items are indeed accepted and stored, and b) the identified tasks are performed in a satisfactory manner. In the case of MDI profiles that are not metadata profiles or of provisions within a metadata profile that are not required data elements the method for determining conformance has to be included within the MDI profile. MDI profile standards have to provide a clear identification of the specific purchaser requirements which are satisfied by the MDI profile. One of the most important roles for MDI profile standard standards is to serve as the basis for the establishment of recognized conformance test suites and test methods. MDI profile standa