Computer Methods and Programs in Biomedicine, 37 (1992) 333-341
333
© 1992 Elsevier Science Publishers B.V. All rights reserved 0169-2607/92/$05.00 COMMET 01289
The European Community: standardization in medical informatics and imaging R. Mattheus
t and J.M. Noothoven van Goor
2
1 European Standardization Committee, CEN TC 251/4 "Imaging and Multi-Media ", Brussels, Belgium and 2 Commission of the European Communities, DG XII1-F / AIM, Brussels, Belgium
The use of informatics and telecommunications in health care and medicine has reached a stage where the application of standards is an absolute requirement. The AIM Programme of the CEC DGXIII stimulated the study of the subject, and has supported the set up of an official European platform for standardization in this field, the CEN TC251. The needs for standardization in one of the subareas, medical imaging, are described in detail. The future solutions of the problems concerned are regarded prerequisites for the general and practical use of PACS and IMACS. Standardization institutes; European research programmes; Medical imaging; PACS-IMACS
1. Introduction: medical informatics Historically, c o m p u t e r systems e n t e r e d t h e h o s p i t a l in two c o r n e r s (see Fig. 1). First, as a device s u p p o r t i n g t h e p e r f o r m a n c e of m e d i c a l e q u i p m e n t , a n d secondly, at a b o u t t h e s a m e p e riod, as an a u t o m a t i c c a r d tray in t h e a c c o u n t i n g d e p a r t m e n t s s u p p o r t i n g s i m p l e office duties. A t t h e e q u i p m e n t side d e d i c a t e d c o m p u t e r s b e c a m e i n d i s p e n s a b l e for c o m p u t e r t o m o g r a p h y , digital angiography, ultrasonic imaging, nuclear m e d i c i n e , m a g n e t i c r e s o n a n c e , a n d analyzers. O n t h e o t h e r h a n d , t h e a u t o m a t i c c a r d tray develo p e d into billing systems, a c c o u n t i n g systems, a n d d e p a r t m e n t a l m a n a g e m e n t systems. T h e overall s i t u a t i o n is still c h a r a c t e r i z e d by s t a n d - a l o n e syst e m s which a r e n o t c o n n e c t e d to e a c h o t h e r , a n d which c o n c e i v a b l y c o u l d n o t even be. This ar-
R. Mattheus, European Standardization Committee, CEN TC 251/4 'Imaging and Multi-media', Brussels, Belgium. Correspondence:
r a n g e m e n t reflects t h a t o f r e l a t i o n s in h e a l t h c a r e in g e n e r a l . H e a l t h c a r e has always b e e n c h a r a c t e r i z e d by small o p e r a t i o n a l units, final r e s p o n s i bility at t h e base, i n d i v i d u a l p a t i e n t s , a b s e n c e o f a u t h o r i t y structures, in s h o r t a g r e a t multiplicity o f t h e basic a n d p r i m a r y o n e - p a t i e n t - o n e - d o c t o r relation. O v e r t h e y e a r s this social s i t u a t i o n led to a significant c h a r a c t e r i s t i c o f m e d i c a l i n f o r m a t i o n as a derivative of m e d i c a l l a n g u a g e . F o r a long t i m e the use of m e d i c a l i n f o r m a t i o n as e x p r e s s e d POS T UPK
I
CAE
CAA
Fig. 1. Computers entered the hospital in two corners: CAE, Computer Aided Equipment; CAA, Computer Aided Administration; POS, Patient Oriented Systems; T, Time; UPK, Use of Pertinent Knowledge.
334
in medical language was practically limited to the primary one-patient-one-doctor relation. Neither a need nor a possibility existed for a wide dissemination, and therefore medical language remained individual, diversified and not generally defined. Moreover, medical language is usually about exceptions, and in some cases could only express the inherent uncertainties of the medical issue. In the past decade technical means to integrate and to communicate became available on a large scale. The diversity of the medical information, however, forms the main obstacle to use these means in health care. It should be emphasized that certainly the highly sophisticated features in operation or in development of current computer systems are scarcely of any use in the administration-oriented systems for health care. The problem of medical informatics is the character of the medical information itself. However, one should not only consider communications over distances. The current generation of systems can accommodate knowledge bases and make accumulation and therefore communications of information over time durations a useful perspective. The combination of both communications m o d e s - - o v e r distance and over time--will create possibilities for systems in health care that are more oriented towards the patient. For example originating from the isolated corner of a single medical apparatus, computers now serve IMACS, image archiving and communications systems. These systems are coupled to a number of medical devices to receive the image data and alphanumeric patient data from the administration systems, and to transmit the information to other places. These systems are patient-oriented. In the other corner the computer that originally replaced the card tray in the accounting department will gradually become a knowledgebased system that supports the administrative staff in planning and accounting as well as the medical staff in deciding on diagnosis and treatment. An orientation towards the patient will also occur here. Eventually, any overall system or combination of systems will combine characteristics of the three corners and handle data from the three sources: the test results, the administrative data,
and the data concerning clinical judgements and the like.
2. The AIM (Advanced Informatics in Medicine) programme By promoting international cooperation in research and development, the Commission of the European Communities (CEC) aims at a number of objectives. Of primary importance are the realization of a common and uniform market and the creation of opportunities for the industries on that market. Two Directorates General of the CEC are in charge of promoting research and development; DGXII for technology research and life sciences; and DGXIII for informatics and telecommunications. Periodically the plans of the CEC are unfolded and updated in the so-called Framework Programme of Research and Development. Well known is the RACE programme (Research and Development of Advanced Communications in Europe). The application of informatics and telecommunications technologies in areas of general interest are also included in the Framework Programme: for instance, for the application in road traffic and transport the programme DRIVE; and for that in education and distant learning the programme DELTA. The AIM programme, Advanced Informatics in Medicine, aims at the promotion of the applications of these technologies in health care and medicine. The general objectives are: the improvement of the efficiency of health care; in reinforcement of the position of the European Community in the field of the medical, biological and health care informatics; and the realization of a favourable climate for a fast implementation and a proper application of informatics in health care. Furthermore, it was considered that the costs of care are high and still rising, and that the applications of informatics and telecommunications form an ideal opportunity to improve the quality, the accessibility, the efficiency and the cost-effectiveness of this care. For each phase and by broad consensus, work plans are composed of tasks that could be carried
335 out through projects. The main activity of the A I M p r o g r a m m e is to select the incoming proposals for these projects and to facilitate and subsidize the selected ones. In the 'cost-shared' model the CEC pays half the costs of the projects. The projects should be undertaken by European consortia formed for the purpose. At least one of the partners of a consortium should be a commercial enterprise in one of the m e m b e r states, and at least one other partner should come from another m e m b e r state. A further requirement is that at least one of the partners is either an institute or a company concerned with medicine or health care. Furthermore, the consortia could have partners from one or more E F T A countries (European Free Trade Association, the countries Austria, Switzerland, Iceland, Norway, Sweden and Finland). The costs E F T A partners incur are not to be refunded by the CEC.
3. AIM contributions to standardization
To advance standardization A I M has undertaken two types of activities. With a long-term objective, contributions to the definition and use of standardization procedures in health care informatics were to be made. Therefore, it was essential to follow the European Community policy on standards and to align with, as well as promote, European and international standards. Addressing the standardization activities in coordination with the international standardization bodies would ensure the coherence of the results, facilitate the widest possible acceptance, and assure the preservation of all parties' interests. A short-term objective was to obtain concrete results during the A I M actions. C o m m o n technical specifications produced during A I M projects were to be made available to the standardization bodies. In its decision of November 4, 1988, adopting the A I M Exploratory Action, the Council of Ministers placed special emphasis on activities related to standardization Annex II of the council decision, which described the summary and objectives of the A I M Action and indicated that
'both industry and health care professionals need and have asked for the cooperation of public authorities because the new systems which could be introduced require common standards at the European level, and if possible at the international level'. The statement made by the Council of Ministers reflected some of the key aspects related to standards in health care informatics during the preparation of the A I M exploratory action, namely: • The urgent need, expressed by all groups that participated in the preparatory activities of AIM, to identify the needs and make progress in this domain. It was also clear that the effective involvement of actors from all the relevant sectors in this field was an essential requirement for success. • The importance of the definition of minimum standards for the development of health care information systems that could interoperate, increasing the effectiveness in their functioning, reducing the development and implementation costs, and providing the industry with the common European-wide standards for the coming internal market. • The need to collaborate with other international organizations and to build on progress already achieved in related domains as a basic element for any effective action on standards in health care informatics. The recommendations made by the Council of Ministers were translated into two tasks of the Workplan of the A I M exploratory action, which addresses explicitly pre-standardization activities. The other tasks, mainly of technical character, include requirements and suggestions to contribute to standardization work in their specific domain. The objectives of the task 'Standardization in the Medical Informatics Environment' are to identify the essential needs for standardization in health care, to survey the existing procedures of standardization, and to make recommendations for a future strategy. Latterly this task has not
336 TABLE 1 AIM projects concerned explicitly with the production of proposals for standards SESAME
EUCLIDES
Semanticsaspects, medical terminology, classification systemsfor drugs, medical procedures Laboratory information exchange; semantics, syntax, and organization
MASQUES
Quality assurance of medical software
QAMS
User requirements; good manufacturing practice; testing facilities in nuclear medicine
SCP-ECG
Digital ECG data transmission, encoding and storage
been dealt with by a specific project, but the accompanying A I M activities, the relations established with other bodies, and the individual contributions of other interested parties to this field have successfully met the objectives. The other task related with standardization aspects is ' A Standard for Software Quality Assurance Plans in Health Care Information Systems'. This task has been covered mainly by the A I M project MASQUES. The results of the A I M Exploratory Action, which was concluded by January 1991, should be found with 42 research and development projects, and accompanying activities, i.e. A I M working groups, workshops, conferences, etc [1]. Some of these contributed substantially to the progress in the area of standards. Five projects addressed standardization activities specifically (see Table 1). Other A I M projects, though their main objectives were not standardization as such, also produced technical specifications and contributed to the establishment of consensus in their specific areas and therefore, de facto, to the European standardization efforts. Moreover many projects have performed, as part of their work plan, a survey of existing standards and future needs [1]. The contributions made by the A I M exploratory action in the field of standards are not limited to the technical results obtained in the projects. The participation of the 250 organizations involved in A I M projects, the A I M work-
shops and seminars on various subjects, and the contact with other bodies, have created the decisive m o m e n t u m and general awareness for the promotion of standards in health care informatics. Contacts and collaboration were established, from the outset, with the European Committee for Standardization (CEN), with the CEC services responsible for promotion of standardization, and with professional associations such as the European Federation of Medical Informatics (EFMI). They are at the base of the outstanding spin-off of A I M in this domain. The mobilization of these groups crystallized in a mandate, BC-IT-05-SI, through which the CEC requested CEN to explore the general aspects of standardization in medical informatics in order to define the requirements in this area. The expected outcome of the mandate was the identification of specific needs, i.e. a kind of draft work programme, and the establishment of the groups required to undertake the follow-up activities [2]. This in its turn led to the establishment of a Technical Committee within CEN, TC251, which may be regarded as the official platform for standardization in the field of health care informatics at the European level. It involves the appropriate organizations, i.e. the European and national standardization institutions of the CEC and E F T A countries, and further interested parties. The CEN TC251 defined seven areas of interest and formed for each area a working group (see section 5) to discuss details and survey project teams in which experts will make the first drafts for standards. A part of the work is assigned to the European Workshop for O p e n Systems (EWOS), which set up a Medical Experts Group. This group concentrates on the data conmmunications aspects and will feed its results into CEN. CEN may start the procedures leading to officially adopted standard in Europe.
4. Why standardization in medical imaging? International product developments are a must for these very expensive medical systems and are
337 crying out for international standards; components of different vendors should communicate without the need to develop special software and hardware convertors. Another important motivation is the exchange of medical information associated with digital images for diagnosis, therapy and patient follow-up. During the last decade, the electrical and electronic engineering sector, particularly affected by the revolutionary developments in microelectronics, have shown the largest growth rates regarding both production and international trade. An important share belongs to biomedical engineering, which is marked by significant developments in electromedical equipment; in particular, digital imaging is moving spectacularly. Electronic messaging systems have the potential to revolutionize the conventional film and paper life of hospitals by replacing these by digital equivalents of traditional medical records. Open standards are the only way to achieve inter-operability between users in a global communication environment at reasonable costs. With the proprietary barriers removed, users can choose which products to buy and which networks to use, on the mere basis of performance, quality, interconnectibility, cost-effectiveness and convenience. Current image generation and IMAC components do not have any standardized interface systems and are not designed to function in a heterogeneous multi-vendor environment. Since the beginning of the implementation of image communications, one of the main problems is the connection of the acquisition units to the network. For instance, different solutions to load images from a modality into a communication and archiving system were applied: • Direct connection of the digital output of the modality. This solution often requires a long software development, especially for old modalities which do not conform to the standard.
• Digitization of films. This solution is the only way to convert existing traditional X-ray images into the patient file. Connection of modalities to a network is not the only interconnecting problem that arises in IMAC. A truly operational IMAC has to be open to the outside world and interfacing with the radiology or hospital information systems for consistent image and administrative databases, as well as with wide area networks for remote communications in tele-radiology. However, digital acquisition units are increasingly being implemented and new methods like digital radiology based on phosfor plates are being introduced, replacing the conventional X-ray systems [3-5].
5. CEN T C 2 5 1 ~ m e d i c a l informatics
The CEN TC251 consists of delegates of the 18 national standardization institutes, and observers from a number of international organizations that are recognized by CEN. The working groups founded by CEN TC251 are composed of experts from various backgrounds whose membership is approved by the national standardization institute concerned. The scope of medical informatics is divided by CEN TC251 into the following domains: • methods and conceptual models (criteria, Health Care Information Model) • information systems for the health sector (subsystems definitions, reference structures) • terminology (encoding systems, mapping or conversions between systems, data definition) • interface and communication (message syntaxes, transfer mechanisms) • quality, protection and security (legal aspects).
• Digitization of the analogue video output of the modality. This solution is much easier to implement but it limits the resolution of images to the video quality.
In the seven areas of interest (see Table 2) these domains will be covered by the seven working groups (see section 3).
338 TABLE 2 CEN TC251 working groups (WG) with area of interest
• representation of complex image structures • related data
WG Area of interest 1
Healthcare information modelling and medical records
2
Healthcare terminology,semantics and knowledge bases
3
Healthcare communicationsand messages
4
Medicalimaging and multi media
5
Medicaldevices
6
Healthcare security and privacy,quality and safety
7
Intermittently connected devices
6. CEN TC251/WG4 'Imaging and Multi-media' By WG4 different items for standardization work are recommended: • functional profiles for medical image interchange • medical image management standards • medical image and related data interchange format standards • off-line media • standard classification and codes for medical image processing • others. The first items were selected by CEN TC251 as very important and work has started in these areas. Functional profiles are the responsibility of E W O S in close cooperation with W G 4 because this item is related to open system protocols. For the others, project teams are set up. First draft proposals are planned for the end of 1992. O f course, close contacts exist with the international activities and the achievements of a unique international standard is a major concern of the working groups. For exchange of images, a standard format is necessary. This format must consist of:
• complex data. Imaging studies can be very complex, and involve many types of data. Images come from various types of modalities in departments like radiology, nuclear medicine, pathology, radiation therapy, etc. For interpretation or further processing, additional image-related information is needed. In particular the definitions of 'image-related data', i.e. patient and medical data related to the study, vary. Some of these can be handled easily (patient name, age, etc.), some by defining conventions (patient orientation), but many definitions and parameters remain complex, as for instance the pulse sequence of M R I and the examination parameters of SPET. A specific image interchange transport profile is needed to meet performance requirements that exceed general medical interchange requirements due to image sizes (0.25-8 Mbyte) and response time constraints. Subsets of the standard will be needed to match different performance requirements, and it is expected that emerging I S O / C C I T T standards for fast LANs and WANs will be adequate for this. A standard command language must be defined, allowing the interpretation and processing of instructions to the other systems. As systems are not conceived for identical purposes, they have different processing capabilities. In order not to interfere with the internal systems, a minimum set of instructions must be defined. For a CT, for instance, complex multiple query is not necessary, but probably is for storage devices. The introduction of image classes may lead in the future to a unified regulation to guarantee the medico-legal background of the use of image processing. The enormous amount of data produced by imaging devices calls for the implementation of highly advanced techniques of data compression to reduce transmission time and volumes undergoing archiving. It is important to know which compression algorithms are used and what the level of destruction is. An image must be
339
identified uniquely world-wide, to facilitate communication in the IMAC world and outside the hospital (Telemedicine). Visualization needs to be common for each device in the department/hospital environment, while software phantoms and material phantoms needs to be standardized. Image generation devices like laser scanners need to be calibrated and to conform with the display device. Common techniques to calibrate systems such as PET and SPET should be developed. Image quality and method of conformance testing of CRT display for medical image presentation in PACS environment as well as spatial resolution, grey scale resolution, brightness and uniformity on the screen are items for standardization. Test patterns to check image quality need to be developed. Quality control and quality assurance should be established. Harmonization of medicolegal information aspects, like archive limits of images, ought to be discussed. In order to allow for a consistent IMAC and HIS database, command functions for minimal information exchange must be standardized. Directory struc-
tures for off-line devices like magneto-optical disks need to be defined so that exchange is possible. This should be coordinated with ongoing work in other areas like terminology and OSI profiles (EWOS). In Fig. 2 an example of an IMAC system is given. Bold words indicate the standardization aspects. All these items have been adopted by CEN TC 251 to work on in the near future.
7. Conclusion There are plenty of experiments all over the world assessing the use of information and communication technology in hospitals. Data processing systems are now usual tools for hospital staff and physicians, thanks to the growing use of hospital or department information systems. Smart cards, expert systems, and wide band networks will surely be part of the physicians' everyday world in the future. In a multi-modality image archiving and communication environment, one of the major prob-
Calibration Specifications
ET
profiles
M Commands
Security IMACS/RIS
Image Processing User interface
Formats and coding
Storage Legal issues Off line devices Fig. 2. Standardization needs in an IMAC environment.
340 lems is the handling of images from different sources having different formats and structures. Networking is a modern-day business phenomenon. In a world that is becoming more interconnected, the issue of communications standards, or perhaps interconnection standards, becomes ever more important. Despite this, various manufacturers of hardware, and even of software, are building products that include their own standards for communications and interconnections. These machines and programs can exclusively communicate with their own kind, but those from other vendors are left out of the resulting 'private network'. Standards cannot be used unless they are really available in the market place, which means that the active early involvement of the suppliers is essential.
For suppliers, open system standards provide the opportunities to compete in a multi-vendor environment world-wide, allowing the flexibility to interface with and accommodate local requirements. Health care communications standards should build on existing open systems standards including OSI, taking full advantage of the investments which have already been made by the computing industry. It is necessary for the support of the standards by the manufacturers of systems platforms, that these standards for health care communications be international (Fig. 3). This standardization effort will bring together different market segments and also influence the products (specifications, cost, etc.). To be cost-effective, a large market segment is necessary and standards are needed to
ISO
CEN Genera/
PT,II
+~
AIM
CEC
BWOS ~ 00~
Underplanning Fig.3. Internationalstandardizationactivities.
341 fulfil this. S t a n d a r d i z a t i o n is not l i m i t e d to comm u n i c a t i o n issues b u t should b e l i n k e d also to t e r m i n o l o g y , coding, privacy, a n d safety. T h e c r e a t i o n of C E N 251 is a m a j o r s t e p in t h e d i r e c t i o n of c o o r d i n a t i n g all t h e s e diverse activities in E u r o p e with a s t r o n g r e l a t i o n to all the i n t e r n a t i o n a l s t a n d a r d i z a t i o n w o r k g r o u p s in the U.S. a n d J a p a n . W e d o not have to r e - i n v e n t the wheel. T h e w o r k d o n e by t h e A I M p r o j e c t s ( A d v a n c e d I n f o r m a t i c s in M e d i c i n e ) o f D G X I I I of the Commission of the European Communities a n d o t h e r actions has p r o v i d e d an e n o r m o u s p l a t form for c o o r d i n a t i n g t h e r e s e a r c h activities a n d even d e v e l o p m e n t s o f d r a f t s t a n d a r d p r o p o s a l s . W e have the possibility to b u i l d f u r t h e r on an efficient m e t h o d a n d n e e d to c o o r d i n a t e all the activities to r e a l i z e s t a n d a r d s [6].
References [1] J. Noothoven van Goor and J,P. Christensen, eds. Advances in Medical Informatics, IOS Press, Amsterdam, in press. [2] Directory of the European Standardisation Requirements for Healthcare Informatics and Programme for the DeL,elopment of Standards, Adopted on 1991-02-28 by CEN/TC
251; Approved by CEN/BT, Version 1.3. [3] K. Minato, M. Komori, Y. Nakano, M.D., Y. Yonekura, M.D., S. Sasayama, T. Takahashi, J. Konishi, K. Sato, and M. Hosoba, Off-line image exchange between two PACS modules using the "ISAC'~ magneto-optical disk, SPIE 1446 (1991) 29. [4] Picture Arehiving and Communications Systems protocol based on ISO-OSI standard, R. Martinez, J. Nam, W.J. Dallas, Univ. of Arizona; M. Osada, Toshiba Corp. Medical Engineering Lab. (Japan); K.M. McNeil, Univ. of Arizona; T. Ozeki, K. Komatsu, Toshiba Corp. Medical Engineering Lab. (Japan); SPIE 1446 (1991) 29. [5] W.J. Chimiak and R.C. Williams, Using the A C R / N E M A standard with T C P / I P and Ethernet, SPIE 1446 (1991) 15. [6] S.W.A. Gunn and N.J. O'Riordan, eds. Health Technology Standards, (IEC/ISO 1991, Dublin, 1990).
333
© 1992 Elsevier Science Publishers B.V. All rights reserved 0169-2607/92/$05.00 COMMET 01289
The European Community: standardization in medical informatics and imaging R. Mattheus
t and J.M. Noothoven van Goor
2
1 European Standardization Committee, CEN TC 251/4 "Imaging and Multi-Media ", Brussels, Belgium and 2 Commission of the European Communities, DG XII1-F / AIM, Brussels, Belgium
The use of informatics and telecommunications in health care and medicine has reached a stage where the application of standards is an absolute requirement. The AIM Programme of the CEC DGXIII stimulated the study of the subject, and has supported the set up of an official European platform for standardization in this field, the CEN TC251. The needs for standardization in one of the subareas, medical imaging, are described in detail. The future solutions of the problems concerned are regarded prerequisites for the general and practical use of PACS and IMACS. Standardization institutes; European research programmes; Medical imaging; PACS-IMACS
1. Introduction: medical informatics Historically, c o m p u t e r systems e n t e r e d t h e h o s p i t a l in two c o r n e r s (see Fig. 1). First, as a device s u p p o r t i n g t h e p e r f o r m a n c e of m e d i c a l e q u i p m e n t , a n d secondly, at a b o u t t h e s a m e p e riod, as an a u t o m a t i c c a r d tray in t h e a c c o u n t i n g d e p a r t m e n t s s u p p o r t i n g s i m p l e office duties. A t t h e e q u i p m e n t side d e d i c a t e d c o m p u t e r s b e c a m e i n d i s p e n s a b l e for c o m p u t e r t o m o g r a p h y , digital angiography, ultrasonic imaging, nuclear m e d i c i n e , m a g n e t i c r e s o n a n c e , a n d analyzers. O n t h e o t h e r h a n d , t h e a u t o m a t i c c a r d tray develo p e d into billing systems, a c c o u n t i n g systems, a n d d e p a r t m e n t a l m a n a g e m e n t systems. T h e overall s i t u a t i o n is still c h a r a c t e r i z e d by s t a n d - a l o n e syst e m s which a r e n o t c o n n e c t e d to e a c h o t h e r , a n d which c o n c e i v a b l y c o u l d n o t even be. This ar-
R. Mattheus, European Standardization Committee, CEN TC 251/4 'Imaging and Multi-media', Brussels, Belgium. Correspondence:
r a n g e m e n t reflects t h a t o f r e l a t i o n s in h e a l t h c a r e in g e n e r a l . H e a l t h c a r e has always b e e n c h a r a c t e r i z e d by small o p e r a t i o n a l units, final r e s p o n s i bility at t h e base, i n d i v i d u a l p a t i e n t s , a b s e n c e o f a u t h o r i t y structures, in s h o r t a g r e a t multiplicity o f t h e basic a n d p r i m a r y o n e - p a t i e n t - o n e - d o c t o r relation. O v e r t h e y e a r s this social s i t u a t i o n led to a significant c h a r a c t e r i s t i c o f m e d i c a l i n f o r m a t i o n as a derivative of m e d i c a l l a n g u a g e . F o r a long t i m e the use of m e d i c a l i n f o r m a t i o n as e x p r e s s e d POS T UPK
I
CAE
CAA
Fig. 1. Computers entered the hospital in two corners: CAE, Computer Aided Equipment; CAA, Computer Aided Administration; POS, Patient Oriented Systems; T, Time; UPK, Use of Pertinent Knowledge.
334
in medical language was practically limited to the primary one-patient-one-doctor relation. Neither a need nor a possibility existed for a wide dissemination, and therefore medical language remained individual, diversified and not generally defined. Moreover, medical language is usually about exceptions, and in some cases could only express the inherent uncertainties of the medical issue. In the past decade technical means to integrate and to communicate became available on a large scale. The diversity of the medical information, however, forms the main obstacle to use these means in health care. It should be emphasized that certainly the highly sophisticated features in operation or in development of current computer systems are scarcely of any use in the administration-oriented systems for health care. The problem of medical informatics is the character of the medical information itself. However, one should not only consider communications over distances. The current generation of systems can accommodate knowledge bases and make accumulation and therefore communications of information over time durations a useful perspective. The combination of both communications m o d e s - - o v e r distance and over time--will create possibilities for systems in health care that are more oriented towards the patient. For example originating from the isolated corner of a single medical apparatus, computers now serve IMACS, image archiving and communications systems. These systems are coupled to a number of medical devices to receive the image data and alphanumeric patient data from the administration systems, and to transmit the information to other places. These systems are patient-oriented. In the other corner the computer that originally replaced the card tray in the accounting department will gradually become a knowledgebased system that supports the administrative staff in planning and accounting as well as the medical staff in deciding on diagnosis and treatment. An orientation towards the patient will also occur here. Eventually, any overall system or combination of systems will combine characteristics of the three corners and handle data from the three sources: the test results, the administrative data,
and the data concerning clinical judgements and the like.
2. The AIM (Advanced Informatics in Medicine) programme By promoting international cooperation in research and development, the Commission of the European Communities (CEC) aims at a number of objectives. Of primary importance are the realization of a common and uniform market and the creation of opportunities for the industries on that market. Two Directorates General of the CEC are in charge of promoting research and development; DGXII for technology research and life sciences; and DGXIII for informatics and telecommunications. Periodically the plans of the CEC are unfolded and updated in the so-called Framework Programme of Research and Development. Well known is the RACE programme (Research and Development of Advanced Communications in Europe). The application of informatics and telecommunications technologies in areas of general interest are also included in the Framework Programme: for instance, for the application in road traffic and transport the programme DRIVE; and for that in education and distant learning the programme DELTA. The AIM programme, Advanced Informatics in Medicine, aims at the promotion of the applications of these technologies in health care and medicine. The general objectives are: the improvement of the efficiency of health care; in reinforcement of the position of the European Community in the field of the medical, biological and health care informatics; and the realization of a favourable climate for a fast implementation and a proper application of informatics in health care. Furthermore, it was considered that the costs of care are high and still rising, and that the applications of informatics and telecommunications form an ideal opportunity to improve the quality, the accessibility, the efficiency and the cost-effectiveness of this care. For each phase and by broad consensus, work plans are composed of tasks that could be carried
335 out through projects. The main activity of the A I M p r o g r a m m e is to select the incoming proposals for these projects and to facilitate and subsidize the selected ones. In the 'cost-shared' model the CEC pays half the costs of the projects. The projects should be undertaken by European consortia formed for the purpose. At least one of the partners of a consortium should be a commercial enterprise in one of the m e m b e r states, and at least one other partner should come from another m e m b e r state. A further requirement is that at least one of the partners is either an institute or a company concerned with medicine or health care. Furthermore, the consortia could have partners from one or more E F T A countries (European Free Trade Association, the countries Austria, Switzerland, Iceland, Norway, Sweden and Finland). The costs E F T A partners incur are not to be refunded by the CEC.
3. AIM contributions to standardization
To advance standardization A I M has undertaken two types of activities. With a long-term objective, contributions to the definition and use of standardization procedures in health care informatics were to be made. Therefore, it was essential to follow the European Community policy on standards and to align with, as well as promote, European and international standards. Addressing the standardization activities in coordination with the international standardization bodies would ensure the coherence of the results, facilitate the widest possible acceptance, and assure the preservation of all parties' interests. A short-term objective was to obtain concrete results during the A I M actions. C o m m o n technical specifications produced during A I M projects were to be made available to the standardization bodies. In its decision of November 4, 1988, adopting the A I M Exploratory Action, the Council of Ministers placed special emphasis on activities related to standardization Annex II of the council decision, which described the summary and objectives of the A I M Action and indicated that
'both industry and health care professionals need and have asked for the cooperation of public authorities because the new systems which could be introduced require common standards at the European level, and if possible at the international level'. The statement made by the Council of Ministers reflected some of the key aspects related to standards in health care informatics during the preparation of the A I M exploratory action, namely: • The urgent need, expressed by all groups that participated in the preparatory activities of AIM, to identify the needs and make progress in this domain. It was also clear that the effective involvement of actors from all the relevant sectors in this field was an essential requirement for success. • The importance of the definition of minimum standards for the development of health care information systems that could interoperate, increasing the effectiveness in their functioning, reducing the development and implementation costs, and providing the industry with the common European-wide standards for the coming internal market. • The need to collaborate with other international organizations and to build on progress already achieved in related domains as a basic element for any effective action on standards in health care informatics. The recommendations made by the Council of Ministers were translated into two tasks of the Workplan of the A I M exploratory action, which addresses explicitly pre-standardization activities. The other tasks, mainly of technical character, include requirements and suggestions to contribute to standardization work in their specific domain. The objectives of the task 'Standardization in the Medical Informatics Environment' are to identify the essential needs for standardization in health care, to survey the existing procedures of standardization, and to make recommendations for a future strategy. Latterly this task has not
336 TABLE 1 AIM projects concerned explicitly with the production of proposals for standards SESAME
EUCLIDES
Semanticsaspects, medical terminology, classification systemsfor drugs, medical procedures Laboratory information exchange; semantics, syntax, and organization
MASQUES
Quality assurance of medical software
QAMS
User requirements; good manufacturing practice; testing facilities in nuclear medicine
SCP-ECG
Digital ECG data transmission, encoding and storage
been dealt with by a specific project, but the accompanying A I M activities, the relations established with other bodies, and the individual contributions of other interested parties to this field have successfully met the objectives. The other task related with standardization aspects is ' A Standard for Software Quality Assurance Plans in Health Care Information Systems'. This task has been covered mainly by the A I M project MASQUES. The results of the A I M Exploratory Action, which was concluded by January 1991, should be found with 42 research and development projects, and accompanying activities, i.e. A I M working groups, workshops, conferences, etc [1]. Some of these contributed substantially to the progress in the area of standards. Five projects addressed standardization activities specifically (see Table 1). Other A I M projects, though their main objectives were not standardization as such, also produced technical specifications and contributed to the establishment of consensus in their specific areas and therefore, de facto, to the European standardization efforts. Moreover many projects have performed, as part of their work plan, a survey of existing standards and future needs [1]. The contributions made by the A I M exploratory action in the field of standards are not limited to the technical results obtained in the projects. The participation of the 250 organizations involved in A I M projects, the A I M work-
shops and seminars on various subjects, and the contact with other bodies, have created the decisive m o m e n t u m and general awareness for the promotion of standards in health care informatics. Contacts and collaboration were established, from the outset, with the European Committee for Standardization (CEN), with the CEC services responsible for promotion of standardization, and with professional associations such as the European Federation of Medical Informatics (EFMI). They are at the base of the outstanding spin-off of A I M in this domain. The mobilization of these groups crystallized in a mandate, BC-IT-05-SI, through which the CEC requested CEN to explore the general aspects of standardization in medical informatics in order to define the requirements in this area. The expected outcome of the mandate was the identification of specific needs, i.e. a kind of draft work programme, and the establishment of the groups required to undertake the follow-up activities [2]. This in its turn led to the establishment of a Technical Committee within CEN, TC251, which may be regarded as the official platform for standardization in the field of health care informatics at the European level. It involves the appropriate organizations, i.e. the European and national standardization institutions of the CEC and E F T A countries, and further interested parties. The CEN TC251 defined seven areas of interest and formed for each area a working group (see section 5) to discuss details and survey project teams in which experts will make the first drafts for standards. A part of the work is assigned to the European Workshop for O p e n Systems (EWOS), which set up a Medical Experts Group. This group concentrates on the data conmmunications aspects and will feed its results into CEN. CEN may start the procedures leading to officially adopted standard in Europe.
4. Why standardization in medical imaging? International product developments are a must for these very expensive medical systems and are
337 crying out for international standards; components of different vendors should communicate without the need to develop special software and hardware convertors. Another important motivation is the exchange of medical information associated with digital images for diagnosis, therapy and patient follow-up. During the last decade, the electrical and electronic engineering sector, particularly affected by the revolutionary developments in microelectronics, have shown the largest growth rates regarding both production and international trade. An important share belongs to biomedical engineering, which is marked by significant developments in electromedical equipment; in particular, digital imaging is moving spectacularly. Electronic messaging systems have the potential to revolutionize the conventional film and paper life of hospitals by replacing these by digital equivalents of traditional medical records. Open standards are the only way to achieve inter-operability between users in a global communication environment at reasonable costs. With the proprietary barriers removed, users can choose which products to buy and which networks to use, on the mere basis of performance, quality, interconnectibility, cost-effectiveness and convenience. Current image generation and IMAC components do not have any standardized interface systems and are not designed to function in a heterogeneous multi-vendor environment. Since the beginning of the implementation of image communications, one of the main problems is the connection of the acquisition units to the network. For instance, different solutions to load images from a modality into a communication and archiving system were applied: • Direct connection of the digital output of the modality. This solution often requires a long software development, especially for old modalities which do not conform to the standard.
• Digitization of films. This solution is the only way to convert existing traditional X-ray images into the patient file. Connection of modalities to a network is not the only interconnecting problem that arises in IMAC. A truly operational IMAC has to be open to the outside world and interfacing with the radiology or hospital information systems for consistent image and administrative databases, as well as with wide area networks for remote communications in tele-radiology. However, digital acquisition units are increasingly being implemented and new methods like digital radiology based on phosfor plates are being introduced, replacing the conventional X-ray systems [3-5].
5. CEN T C 2 5 1 ~ m e d i c a l informatics
The CEN TC251 consists of delegates of the 18 national standardization institutes, and observers from a number of international organizations that are recognized by CEN. The working groups founded by CEN TC251 are composed of experts from various backgrounds whose membership is approved by the national standardization institute concerned. The scope of medical informatics is divided by CEN TC251 into the following domains: • methods and conceptual models (criteria, Health Care Information Model) • information systems for the health sector (subsystems definitions, reference structures) • terminology (encoding systems, mapping or conversions between systems, data definition) • interface and communication (message syntaxes, transfer mechanisms) • quality, protection and security (legal aspects).
• Digitization of the analogue video output of the modality. This solution is much easier to implement but it limits the resolution of images to the video quality.
In the seven areas of interest (see Table 2) these domains will be covered by the seven working groups (see section 3).
338 TABLE 2 CEN TC251 working groups (WG) with area of interest
• representation of complex image structures • related data
WG Area of interest 1
Healthcare information modelling and medical records
2
Healthcare terminology,semantics and knowledge bases
3
Healthcare communicationsand messages
4
Medicalimaging and multi media
5
Medicaldevices
6
Healthcare security and privacy,quality and safety
7
Intermittently connected devices
6. CEN TC251/WG4 'Imaging and Multi-media' By WG4 different items for standardization work are recommended: • functional profiles for medical image interchange • medical image management standards • medical image and related data interchange format standards • off-line media • standard classification and codes for medical image processing • others. The first items were selected by CEN TC251 as very important and work has started in these areas. Functional profiles are the responsibility of E W O S in close cooperation with W G 4 because this item is related to open system protocols. For the others, project teams are set up. First draft proposals are planned for the end of 1992. O f course, close contacts exist with the international activities and the achievements of a unique international standard is a major concern of the working groups. For exchange of images, a standard format is necessary. This format must consist of:
• complex data. Imaging studies can be very complex, and involve many types of data. Images come from various types of modalities in departments like radiology, nuclear medicine, pathology, radiation therapy, etc. For interpretation or further processing, additional image-related information is needed. In particular the definitions of 'image-related data', i.e. patient and medical data related to the study, vary. Some of these can be handled easily (patient name, age, etc.), some by defining conventions (patient orientation), but many definitions and parameters remain complex, as for instance the pulse sequence of M R I and the examination parameters of SPET. A specific image interchange transport profile is needed to meet performance requirements that exceed general medical interchange requirements due to image sizes (0.25-8 Mbyte) and response time constraints. Subsets of the standard will be needed to match different performance requirements, and it is expected that emerging I S O / C C I T T standards for fast LANs and WANs will be adequate for this. A standard command language must be defined, allowing the interpretation and processing of instructions to the other systems. As systems are not conceived for identical purposes, they have different processing capabilities. In order not to interfere with the internal systems, a minimum set of instructions must be defined. For a CT, for instance, complex multiple query is not necessary, but probably is for storage devices. The introduction of image classes may lead in the future to a unified regulation to guarantee the medico-legal background of the use of image processing. The enormous amount of data produced by imaging devices calls for the implementation of highly advanced techniques of data compression to reduce transmission time and volumes undergoing archiving. It is important to know which compression algorithms are used and what the level of destruction is. An image must be
339
identified uniquely world-wide, to facilitate communication in the IMAC world and outside the hospital (Telemedicine). Visualization needs to be common for each device in the department/hospital environment, while software phantoms and material phantoms needs to be standardized. Image generation devices like laser scanners need to be calibrated and to conform with the display device. Common techniques to calibrate systems such as PET and SPET should be developed. Image quality and method of conformance testing of CRT display for medical image presentation in PACS environment as well as spatial resolution, grey scale resolution, brightness and uniformity on the screen are items for standardization. Test patterns to check image quality need to be developed. Quality control and quality assurance should be established. Harmonization of medicolegal information aspects, like archive limits of images, ought to be discussed. In order to allow for a consistent IMAC and HIS database, command functions for minimal information exchange must be standardized. Directory struc-
tures for off-line devices like magneto-optical disks need to be defined so that exchange is possible. This should be coordinated with ongoing work in other areas like terminology and OSI profiles (EWOS). In Fig. 2 an example of an IMAC system is given. Bold words indicate the standardization aspects. All these items have been adopted by CEN TC 251 to work on in the near future.
7. Conclusion There are plenty of experiments all over the world assessing the use of information and communication technology in hospitals. Data processing systems are now usual tools for hospital staff and physicians, thanks to the growing use of hospital or department information systems. Smart cards, expert systems, and wide band networks will surely be part of the physicians' everyday world in the future. In a multi-modality image archiving and communication environment, one of the major prob-
Calibration Specifications
ET
profiles
M Commands
Security IMACS/RIS
Image Processing User interface
Formats and coding
Storage Legal issues Off line devices Fig. 2. Standardization needs in an IMAC environment.
340 lems is the handling of images from different sources having different formats and structures. Networking is a modern-day business phenomenon. In a world that is becoming more interconnected, the issue of communications standards, or perhaps interconnection standards, becomes ever more important. Despite this, various manufacturers of hardware, and even of software, are building products that include their own standards for communications and interconnections. These machines and programs can exclusively communicate with their own kind, but those from other vendors are left out of the resulting 'private network'. Standards cannot be used unless they are really available in the market place, which means that the active early involvement of the suppliers is essential.
For suppliers, open system standards provide the opportunities to compete in a multi-vendor environment world-wide, allowing the flexibility to interface with and accommodate local requirements. Health care communications standards should build on existing open systems standards including OSI, taking full advantage of the investments which have already been made by the computing industry. It is necessary for the support of the standards by the manufacturers of systems platforms, that these standards for health care communications be international (Fig. 3). This standardization effort will bring together different market segments and also influence the products (specifications, cost, etc.). To be cost-effective, a large market segment is necessary and standards are needed to
ISO
CEN Genera/
PT,II
+~
AIM
CEC
BWOS ~ 00~
Underplanning Fig.3. Internationalstandardizationactivities.
341 fulfil this. S t a n d a r d i z a t i o n is not l i m i t e d to comm u n i c a t i o n issues b u t should b e l i n k e d also to t e r m i n o l o g y , coding, privacy, a n d safety. T h e c r e a t i o n of C E N 251 is a m a j o r s t e p in t h e d i r e c t i o n of c o o r d i n a t i n g all t h e s e diverse activities in E u r o p e with a s t r o n g r e l a t i o n to all the i n t e r n a t i o n a l s t a n d a r d i z a t i o n w o r k g r o u p s in the U.S. a n d J a p a n . W e d o not have to r e - i n v e n t the wheel. T h e w o r k d o n e by t h e A I M p r o j e c t s ( A d v a n c e d I n f o r m a t i c s in M e d i c i n e ) o f D G X I I I of the Commission of the European Communities a n d o t h e r actions has p r o v i d e d an e n o r m o u s p l a t form for c o o r d i n a t i n g t h e r e s e a r c h activities a n d even d e v e l o p m e n t s o f d r a f t s t a n d a r d p r o p o s a l s . W e have the possibility to b u i l d f u r t h e r on an efficient m e t h o d a n d n e e d to c o o r d i n a t e all the activities to r e a l i z e s t a n d a r d s [6].
References [1] J. Noothoven van Goor and J,P. Christensen, eds. Advances in Medical Informatics, IOS Press, Amsterdam, in press. [2] Directory of the European Standardisation Requirements for Healthcare Informatics and Programme for the DeL,elopment of Standards, Adopted on 1991-02-28 by CEN/TC
251; Approved by CEN/BT, Version 1.3. [3] K. Minato, M. Komori, Y. Nakano, M.D., Y. Yonekura, M.D., S. Sasayama, T. Takahashi, J. Konishi, K. Sato, and M. Hosoba, Off-line image exchange between two PACS modules using the "ISAC'~ magneto-optical disk, SPIE 1446 (1991) 29. [4] Picture Arehiving and Communications Systems protocol based on ISO-OSI standard, R. Martinez, J. Nam, W.J. Dallas, Univ. of Arizona; M. Osada, Toshiba Corp. Medical Engineering Lab. (Japan); K.M. McNeil, Univ. of Arizona; T. Ozeki, K. Komatsu, Toshiba Corp. Medical Engineering Lab. (Japan); SPIE 1446 (1991) 29. [5] W.J. Chimiak and R.C. Williams, Using the A C R / N E M A standard with T C P / I P and Ethernet, SPIE 1446 (1991) 15. [6] S.W.A. Gunn and N.J. O'Riordan, eds. Health Technology Standards, (IEC/ISO 1991, Dublin, 1990).
