articles+ search results

Hospitals, United States, Computers standards, Information Systems standards, and Software standards

Humans, Pedigree, Data Collection, Database Management Systems, Genetic Diseases, Inborn, and Software

This work examines some of the problems encountered in developing small and large database application systems involving human genetics data collection efforts that include data on individuals as well as family pedigree data. Rapid prototyping of a database application requires software tools to produce the application with little or no programming. Features of MEGADATS-4 that provide for rapid prototyping and for producing stand-alone applications are examined.

Database Management Systems, Medical Informatics Applications, Programming Languages, Software Design, Information Systems, and Software

AIDA consists of a set of software tools to allow for fast development and easy-to-maintain Medical Information Systems. AIDA supports all aspects of such a system both during development and operation. It contains tools to build and maintain forms for interactive data entry and on-line input validation, a database management system including a data dictionary and a set of run-time routines for database access, and routines for querying the database and output formatting. Unlike an application generator, the user of AIDA may select parts of the tools to fulfill his needs and program other subsystems not developed with AIDA. The AIDA software uses as host language the ANSI-standard programming language MUMPS, an interpreted language embedded in an integrated database and programming environment. This greatly facilitates the portability of AIDA applications. The database facilities supported by AIDA are based on a relational data model. This data model is built on top of the MUMPS database, the so-called global structure. This relational model overcomes the restrictions of the global structure regarding string length. The global structure is especially powerful for sorting purposes. Using MUMPS as a host language allows the user an easy interface between user-defined data validation checks or other user-defined code and the AIDA tools. AIDA has been designed primarily for prototyping and for the construction of Medical Information Systems in a research environment which requires a flexible approach. The prototyping facility of AIDA operates terminal independent and is even to a great extent multi-lingual. Most of these features are table-driven; this allows on-line changes in the use of terminal type and language, but also causes overhead. AIDA has a set of optimizing tools by which it is possible to build a faster, but (of course) less flexible code from these table definitions. By separating the AIDA software in a source and a run-time version, one is able to write implementation-specific code which can be selected and loaded by a special source loader, being part of the AIDA software. This feature is also accessible for maintaining software on different sites and on different installations.

Drug Information Services, Netherlands, Hospital Information Systems, Pharmacy Service, Hospital, and Software

The CENTRASYS system for the Hospital Pharmacy, developed as part of a research project of the Department of Medical Informatics is described. The role of AIDA, a fourth-generation software package, as a prototyping tool is discussed. It is concluded that AIDA facilitates prototyping and is also very suitable as a vehicle for systems in operation. It is further concluded that prototyping is of great help in the developmental phase of a project, but that great care has to be taken during evaluation of the prototypes: minimize the number of test sites and try to avoid that users become dependent on the system, because every prototype needs further tuning before it really becomes an operational system.

Evaluation Studies as Topic, Hospital Information Systems, Pharmacy Service, Hospital, Primary Health Care, Software Design, and Software

A system for hospital pharmacies (CENTRASYS) and a system for primary health care (ELIAS), both developed using prototyping and a fourth-generation tool (AIDA), are introduced. Differences in development strategies are analyzed and conclusions are drawn with respect to the use of AIDA for management, development and operation of the systems. The use of AIDA increases development speed enormously, enabling a productivity of over 40 lines per day, which is more than twice the amount that is accepted as reasonable.

Animals, Cricetinae, Netherlands, Pilot Projects, Software Design, User-Computer Interface, Information Systems, Primary Health Care, and Software

In this article the development of a computer system for General Practice, ELIAS, is described. The use of the 4th-generation software toolkit AIDA proved to be very helpful in increasing the speed of development as well as the quality of the ELIAS software. The programming support that AIDA offered, not only in increasing the rate of development but also in the flexible way in which parts of the system and the database can be adjusted (in prototyping as well as in the operational system) and its self-documenting functions, contributed to the ease of development. The consistent lay-out of the frames and uniform screen-handling, the opportunity of data validation and the availability of help information at every item in screen frames--all facilitated by AIDA--rendered ELIAS a very user-friendly system.

Decision Making, Organizational, Models, Theoretical, United States, Computer Systems, Management Information Systems organization administration, and Public Health Administration organization administration

Human services agencies are closer than ever to fulfillment of their authoritative role. A critical step is transformation of the Reporting System to a Management Information System. This creates the information structure and mind set necessary to generate new, data-based ideas. There are too many obstacles to traditional MIS development approaches in agencies, however. New strategies such as selective use of end-user technology and prototyping can provide methods that overcome these obstacles.

Blood Glucose Self-Monitoring, Diabetes Mellitus blood, Diabetes Mellitus physiopathology, Diet, Diabetic, Exercise, Humans, Insulin physiology, Microcomputers, Numerical Analysis, Computer-Assisted, Prognosis, Blood Glucose metabolism, Diabetes Mellitus drug therapy, Expert Systems, Insulin administration dosage, and Therapy, Computer-Assisted

This paper describes the principles and prototyping of a computer-based system being developed to assist in the management of diabetes mellitus. Unlike other approaches based upon mathematical modelling or the use of computer algorithms, this system adopts one derived from artificial intelligence, seeking to incorporate the dynamics of glucose and insulin in a manner which reflects their clinical importance. The resultant logical model (qualitative algebra) defines the relationships between changes in insulin dose and site and time of injection and glycaemic response. In this manner the computer-based system, implemented in Prolog, can be used to provide advice concerning insulin therapy by means of making qualitative predictions of patient outcome of blood glucose profile resulting from alternative insulin regimens.

Adult, Decision Making, Computer-Assisted, Humans, Pulmonary Gas Exchange, Signal Processing, Computer-Assisted, Carbon Dioxide blood, Expert Systems, Respiratory Insufficiency therapy, Software, and Ventilators, Mechanical

The KUSIVAR is an expert system for mechanical ventilation of adult patients suffering from respiratory insufficiency. Its main objective is to provide guidance in respirator management. The knowledge base includes both qualitative, rule-based knowledge and quantitative knowledge expressed in the form of mathematical models (expert control) which is used for prediction of arterial gas tensions and optimization purposes. The system is data driven and uses a forward chaining mechanism for rule invocation. The interaction with the user will be performed in advisory, critiquing, semi-automatic and automatic modes. The system is at present in an advanced prototype stage. Prototyping is performed using KEE (Knowledge Engineering Environment) on a Sperry Explorer workstation. For further development and clinical use the expert system will be downloaded to an advanced PC. The system is intended to support therapy with a Siemens-Elema Servoventilator 900 C.

Efficiency, Models, Theoretical, Planning Techniques, United States, and Hospital Information Systems

One way automation can increase efficiency is through rapid prototyping, particularly of user interfaces. AI and logic programming, argues this author, offer good user interface tools and a suitable prototyping environment.

Magnetic Resonance Imaging, Tomography, Emission-Computed, Tomography, X-Ray Computed, Ultrasonography, Image Processing, Computer-Assisted methods, Software, Software Design, and User-Computer Interface

A comprehensive software package, called ANALYZE, has been developed (1) which permits detailed investigation and evaluation of multidimensional biomedical images. ANALYZE can be used with 3-D imaging modalities based on x-ray computed tomography, radionuclide emission tomography, ultrasound tomography, and magnetic resonance imaging. The software is written entirely in "C" and runs on standard UNIX workstations. The ANALYZE package features integrated, complimentary tools for fully interactive display, manipulation and measurement of multidimensional image data. The software architecture permits systematic enhancements and upgrades which has fostered development of a readily expandable package. It provides an effective shell for custom software prototyping and turnkey applications. This paper provides a general description of this software as well as specific details on the methodology employed to develop it, both conceptual and technical. Applications of the software are illustrated.

Amino Acid Sequence, Chemical Phenomena, Chemistry, Protein Conformation, Information Systems, and Proteins

An object-oriented database system has been developed which is being used to store protein structure data. The database can be queried using the logic programming language Prolog or the query language Daplex. Queries retrieve information by navigating through a network of objects which represent the primary, secondary and tertiary structures of proteins. Routines written in both Prolog and Daplex can integrate complex calculations with the retrieval of data from the database, and can also be stored in the database for sharing among users. Thus object-oriented databases are better suited to prototyping applications and answering complex queries about protein structure than relational databases. This system has been used to find loops of varying length and anchor positions when modelling homologous protein structures.

The aim of this study was to evaluate and improve the menu interface design of an existing expert system. The system provided expertise concerned with evaluating human response to environments and was implemented onto a computer with a simple tree menu system. Two laboratory based experiments were carried out in which alternative menu interface designs were developed rapidly and compared with the original design. User acceptance tests which incorporated objective and subjective measures were iteratively used to evaluate and improve the interface designs. The results of these experiments indicated that, for the particular system under study, a graphic based design which displayed 58 options divided into levels on a single screen was preferred by users over the original menu interface which displayed one menu at a time with seven options per screen. The final interface remains to be tested under field conditions.

Hospital Information Systems, Microcomputers, North Carolina, Software, Computer Communication Networks, Information Systems, Medical Records Systems, Computerized, and User-Computer Interface

Many hospitals today have implemented widely disparate information systems on mainframe and mini-computer hardware. The advent of network technology in hospitals has made it possible to access information in these systems. Unfortunately, the user interfaces to applications on these system are unique and difficult to learn, which makes them unsuitable for use by clinical services. In this paper we describe the development using rapid prototyping object-oriented programming tools of a Physician's Workstation which integrates information from five different applications running on three separate computer systems.

Clinical Laboratory Information Systems, Critical Care, Decision Making, Computer-Assisted, Denmark, Diagnosis, Computer-Assisted, Expert Systems, Finland, Microcomputers, Monitoring, Physiologic, Sweden, Therapy, Computer-Assisted, User-Computer Interface, and Artificial Intelligence

A Nordic research and development programme, 'KBS in Medicine' (KUSIN-MEDICINE), was run in 1986-89. Its main goal was to acquire an understanding of applying knowledge-based techniques in medicine and of the limitations of present-day artificial intelligence (AI) methodologies. The programme comprised four experimental installation sites (Tampere in Finland, Uppsala and Linköping in Sweden, and Aalborg in Denmark) each prototyping in one or more medical domains. The programme was financed by the Nordic Fund for Technological and Industrial Development, by national funds for applied research and by a number of industries. Prototype decision support systems were produced in the following domains: intensive care (Tampere, Uppsala, Linköping, Aalborg), clinical chemistry (Tampere, Uppsala) and clinical neurophysiology (Aalborg in collaboration with Turku and Uppsala). These served to transfer this technology to industry and helped to identify limitations of this technology.

Computer Graphics, Computer Simulation, Computer User Training, Fourier Analysis, General Surgery methods, Magnetic Resonance Imaging, Radiotherapy methods, Tomography, X-Ray Computed, Ultrasonography, Diagnostic Imaging, Image Interpretation, Computer-Assisted, Models, Anatomic, and Software Design

A comprehensive software system called ANALYZE has been developed which permits detailed investigation and evaluation of 3-D biomedical images. The software can be used with any 2-D or 3-D imaging modality, including x-ray computed tomography, radionuclide emission tomography, ultrasound tomography, magnetic resonance imaging and both light and electron microscopy. The package is unique in its synergistic integration of fully interactive modules for direct display, manipulation and measurement of multidimensional image data. Several original algorithms are included which improve image display efficiency and quality. One of the most versatile and powerful algorithms is interactive volume rendering, which is optimized to be fast without compromising image quality. An important advantage of this technique is to display 3-D images directly from the original data and to provide on-the-fly combinations of selected image transformations and/or volume set operations (union, intersection, difference, etc.). The inclusion of a variety of interactive editing and quantitative mensuration tools significantly extends the usefulness of the software. Any curvilinear path or region-of-interest can be manually specified and/or automatically segmented for numerical determination and statistical analyses of distances, areas, volumes, shapes, densities and textures. ANALYZE is written entirely in "C" and runs on several standard UNIX workstations. It is being used in a variety of applications by over 40 institutions around the world, and has been licensed by Mayo to several imaging companies. The software architecture permits systematic enhancements and upgrades which has fostered development of a readily expandable package. ANALYZE comprises a powerful "visualization workshop" for rapid prototyping of specific application packages, including applications to interactive surgery simulation and radiation treatment planning. ANALYZE offers the potential to accurately and reproducibly examine, from images, the structure and function of any cell, tissue, limb, organ or organ system of the body, much like a surgeon or pathologist might do in real life, but entirely non-invasively, without pain or destruction of tissue. These capabilities promise exciting new insights into the basic processes of life, and major advances in health care delivery through improved diagnosis and treatment of disease.

Brain diagnostic imaging, Humans, Skull diagnostic imaging, Software, Image Processing, Computer-Assisted methods, and Radiography

Computer applications in radiology are evolving rapidly, tied to incremental improvements in hardware, software, and methods. In computer hardware, the emergence of dramatically improved graphic and computational performance for engineering workstations enables their use for visualization. Major changes in networking, storage, and display technology play a major role in influencing applications. The use of three-dimensional digitizers to perform localization of real three-dimensional points in conjunction with images and the rendering of objects using rapid prototyping methods, such as stereolithography, were recently reported. Major software advances have taken place through the availability of applications packages that are operated with menu-driven or point-and-click user interfaces, data flow languages, or complete turnkey applications. Imaging methods including CT, MR imaging, digital radiography, biomagnetism, and optical range sensing, which take advantage of advanced computer technology, are new this year. Image processing for multimodality fusion or image registration, visualization, reconstruction, and quantification of images, have been reported at a wide variety of conferences and in key publications. New computer methods to fabricate custom orthopaedic implants, and to improve imaging technology assessment were introduced.

Computer Graphics, Programming Languages, Hospital Information Systems, Medical Records Systems, Computerized, and User-Computer Interface

The PRIST-2 system has been designed as an interactive and high-productivity tool for the rapid prototyping and development of medical applications. Three major issues were addressed in this research project which derived from the evolution of a previous 4th generation software package, called PRIST (patient record information system tool): a high transportability on different hardware and operating systems, a conversational and interactive user-interface and user-independence Relational Data Base Management System (RDBMS). Although we developed PRIST-2 on the top of the ORACLE RDBMS, it does not depend on SQL commercial products because the ORACLE features have been directly used only for SQL relational data base management. The application design methodology implemented in the system architecture allows an interactive and formal description of the application constraints in terms of the semantic data model rather than in terms of the data structure. The translation of the conceptual constraints into SQL tables is performed by several pre-defined routines. In the PC based release (MS/DOS, OS/2, Xenix operating systems), the Graphic-User Interface (GUI) has been developed using Microsoft Windows Software Development Kit. The UNIX release will use a GUI developed on top of the X-Windows environment.

Adult, Breast Neoplasms pathology, Carcinoma pathology, Computer Systems, Decision Theory, Decision Trees, Diagnosis, Computer-Assisted, Expert Systems, Female, Humans, Programming Languages, Decision Support Techniques, Medical Informatics, and Software Design

The concept of object-oriented design and programming has recently received a great deal of attention from the software engineering community. This paper highlights the realisable benefits of using the object-oriented approach in the design and development of clinical decision support systems. These systems seek to build a computational model of some problem domain and therefore tend to be exploratory in nature. Conventional procedural design techniques do not support either the process of model building or rapid prototyping. The central concepts of the object-oriented paradigm are introduced, namely encapsulation, inheritance and polymorphism, and their use illustrated in a case study, taken from the domain of breast histopathology. In particular, the dual roles of inheritance in object-oriented programming are examined, i.e., inheritance as a conceptual modelling tool and inheritance as a code reuse mechanism. It is argued that the use of the former is not entirely intuitive and may be difficult to incorporate into the design process. However, inheritance as a means of optimising code reuse offers substantial technical benefits.

Drug Prescriptions, Medical Records Systems, Computerized, Nursing, Ambulatory Care, Artificial Intelligence, and Practice Guidelines as Topic

As we understand the process of ambulatory care better, the need to effectively implement standards of practice becomes more apparent. To facilitate successful use of practice guidelines, we have integrated an artificial intelligence system of Medical Logic Modules into our computerized medical record. A rule shell allows rapid development and prototyping of rules which can be practice reminders, information gathering utilities, or standing orders. A set of utilities allows non-programmer clinicians to develop and maintain the rule set. We will demonstrate these enhancements in the context of the comprehensive patient record.

Cost-Benefit Analysis, Decision Making, Organizational, Decision Support Techniques, Models, Structural, Planning Techniques, Product Line Management economics, Professional Staff Committees economics, Professional Staff Committees organization administration, United States, Industry organization administration, and Product Line Management methods

Extended development cycles put companies at risk through loss of sales, margins, market share, and credibility as innovators. The author suggests constructing early-stage models to provide a dress rehearsal for new products and help companies develop products in less time.

Equipment Design, Signal Processing, Computer-Assisted, Software Design, User-Computer Interface, Rehabilitation instrumentation, and Software

Rapid prototyping is a quick, efficient way to evaluate new electrical instruments. A hardware interface between a computer and an instrument can be simulated in software. The authors demonstrate the technique of rapid prototyping by developing interfaces for two therapeutic strength-testing devices and an electromagnetic tracker/digitizer. The LabVIEW rapid prototyping software tool was used to create "virtual instruments," which combine to form interfaces. The functions and connections of each virtual instrument are described.

Rapid prototyping or 'virtual prototyping' of human-machine interfaces offers the possibility of putting the human operator 'in the loop' without the effort and cost associated with conventional man-in-the-loop simulation. Advocates suggest that rapid prototyping is compatible with conventional systems development techniques. It is not clear, however, exactly how rapid prototyping could be used in relation to conventional human factors engineering analyses. Therefore, an investigation of the use of the VAPS virtual prototyping system was carried out in five organizations. The results show that a variety of task analysis approaches can be used to initiate rapid prototyping. Overall, it appears that rapid prototyping facilitates an iterative approach to the development of the human-machine interface, and that is most applicable to the early stages of systems development, rather than to detailed design.

Computer Communication Networks, Computer Systems, Databases, Bibliographic, Databases, Factual, Information Storage and Retrieval, National Library of Medicine (U.S.), United States, Academic Medical Centers, Integrated Advanced Information Management Systems, and Unified Medical Language System

The paper describes a prototype information environment designed to link network-based information resources in an integrated fashion and thus enhance the information capabilities of an academic medical center. The prototype was implemented on a single Macintosh computer to permit exploration of the overall "information architecture" and to demonstrate the various desired capabilities prior to full-scale network-based implementation. At the heart of the prototype are two components: a diverse set of information resources available over an institutional computer network and an information sources map designed to assist users in finding and accessing information resources relevant to their needs. The paper describes these and other components of the prototype and presents a scenario illustrating its use. The prototype illustrates the link between the goals of two National Library of Medicine initiatives, the Integrated Academic Information Management System (IAIMS) and the Unified Medical Language System (UMLS).

Clinical Protocols, Semantics, Database Management Systems organization administration, Hospital Information Systems organization administration, Software Design, and User-Computer Interface

A 4th generation tool, called PRIST-2, is presented that has been designed as an interactive environment for the rapid prototyping of clinical applications in a large-scale Hospital Information System project. We adopted an SQL-based commercial Relational Data Base Management Systems (RDBMS) to guarantee portability on different hardware and operating systems. Relational databases, however, are characterized by a simple data structure and do not incorporate the application semantics required to ensure a high degree of data independence. To reach this goal, we propose an extension to the relational model, adding some of the main characteristics of the Object Oriented Data Base Management Systems (OODBMS) approach, such as "types" and "encapsulation".

Computer Literacy, Humans, Mid-Atlantic Region, Organizational Culture, Organizational Innovation, User-Computer Interface, Ambulatory Care Information Systems statistics numerical data, Attitude to Computers, Managed Care Programs, and Physicians psychology

Kaiser Permanente Mid-Atlantic States has developed a fully integrated outpatient information system which currently runs on an IBM ES9000 on a VM platform written in MUMPS. The applications include Lab, Radiology, Transcription, Appointments. Pharmacy, Encounter tracking, Hospitalizations, Referrals, Phone Advice, Pap tracking, Problem list, Immunization tracking, and Patient demographics. They are department specific and require input and output from a dumb terminal. We have developed a physician's work station to access this information using PC compatible computers running Microsoft Windows and a custom Microsoft Visual Basic 2.0 environment which draws from these 14 applications giving the physician a comprehensive view of all electronic medical records. Through rapid prototyping, voluntary participation, formal training and gradual implementation we have created an enthusiastic response. 95% of our physician PC users access the system each month. The use ranges from 0.2 to 3.0 screens of data viewed per patient visit. This response continues to drive the process toward still greater user acceptance and further practice enhancement.

Computer Systems, Humans, Physicians, Hospital Information Systems statistics numerical data, Medical Records Systems, Computerized statistics numerical data, and Software Design

The M.D. Rounds Report program was developed and implemented in June of 1992 as an adjunct to the HELP System at Rex Hospital. The program facilitates rapid access to information on allergies and current medications, laboratory results, radiology reports and therapist notes for a list of patients without physicians having to make additional menu or submenu selections. In planning for an upgrade of the program, utilization statistics and user feedback provided valuable information in terms of frequency of access, features used and unused, and the value of the program as a reporting tool in comparison to other online results reporting applications. A brief description of the functionality of the M.D. Rounds Report, evaluation of the program audit trail and user feedback, planned enhancements to the program, and a discussion of the prototyping and monitoring experience and the impact on future physician subsystem development will be presented.

Humans, Medical Records Systems, Computerized, Microcomputers, Ambulatory Care Information Systems, Family Practice, and User-Computer Interface

ISAAC (Integrated System Architecture for Advanced Primary Care) is a project aiming at developing information technology and telematic support in the specific field of General Practice--and more broadly in the Primary Health Care sector--within the health care systems of different European Countries. The project aims at improving the work of the General Practitioners through the development of a useful and usable medical workstation for day-to-day patient care. Moreover ISAAC has the goal of prototyping an integration architecture for the improvement of the communications between the ISAAC workstation and heterogeneous application environments, namely other components of the health care system. This paper deals with a general description of the design along with a discussion of the adopted approach to fulfill the integration requirements.

Computer Communication Networks standards, Computer Systems standards, Data Collection standards, Forecasting, Humans, Medical Informatics Applications, Medical Records Systems, Computerized standards, Telemedicine standards, Unified Medical Language System, Medical Informatics standards, Multimedia standards, and Radiology Information Systems standards

This paper is attempting given a summery of the major building blocks and driving forces in the developments of medical informatics and medical imaging in special. The role of multi-media and broadband communication will be described. The paper should give an indication where the author sees medical imaging in the world of informatics, focusing from R&D to product developments, with emphases on standards and prototyping. The author will also define the molecule and atoms of medical informatics and medical imaging. The architecture of the CEN TC 251/4 draft standard will be described in relation to the general objectives of CEN TC 251.

Blood Glucose metabolism, Diabetes Mellitus, Type 1 blood, Evaluation Studies as Topic, Expert Systems, Humans, Microcomputers, Models, Theoretical, Sensitivity and Specificity, Software, Diabetes Mellitus, Type 1 drug therapy, Insulin administration dosage, Software Validation, and Therapy, Computer-Assisted

This paper describes the principles and prototyping of a computer system to assist in the treatment of patients with insulin-dependent (type 1) diabetes mellitus. The system adopts a mixed approach involving rule-based qualitative algebra and a dynamic mathematical model to define the relationships between insulin dosage, diet and glycaemic response. The rule-based system (KBS), implemented in PROLOG, can be used to generate qualitative therapeutic advice. These suggestions are quantified and rank-ordered by the use of a mathematical model of glucose-insulin interaction in type 1 diabetes mellitus, with parameters adjusted for individual patients. In this paper an overview of the integrated prototype, linking the KBS and model, is provided and a case study used to demonstrate the principles of the system in operation. The results of verification and validation work performed on the KBS are described.

Humans, Skull anatomy histology, Skull diagnostic imaging, Tomography, X-Ray Computed, and Image Processing, Computer-Assisted methods

This paper describes current research into the creation of solid models which replicate anatomical structures using rapid prototyping techniques. Stereolithography is particularly efficient in the production of highly-complex structures. This technique was applied to the fabrication of a plastic model of a human skull. A geometric definition of the object was obtained by transferring the three-dimensional medical image volume (x-ray CT) and processing the data on a computer graphics workstation. A 3-D biomedical visualisation software package (ANALYZETM) was used to perform segmentation of structures. A 3-D triangular-mesh representation of the selected structure was calculated and converted to a format suitable for processing and construction using stereolithography (SLA). Improvements in the quality of the anatomical model produced will result from improved data processing techniques. Future work is proposed to investigate the influence of imaging parameters and data processing techniques on the resultant plastic models.

Clinical Protocols, Data Display, Database Management Systems, Databases, Factual, Humans, Medical Oncology, Software Design, Computer Graphics, Expert Systems, Neoplasms therapy, and User-Computer Interface

We describe a graphic user interface for an expert system in oncology. The main objectives of our work has been to facilitate the adaptation of the system to different clinical environments and potentiate the factors which more directly determine the acceptance of the system by its users. We present the design principles derived from the features of the clinical domain chosen and from the objectives of the system. These principles are reflected on the design of the screen and of the interaction and in the style of integration of the interface with the other components of the system. Underlying the application we describe is a graphic user interface management system which provides facilities for the fast prototyping and integration of interfaces. We describe here those features of this tool which make the practical application of the design principles we consider possible.

Nonlinear Dynamics, Algorithms, and Neural Networks, Computer

This paper describes a novel neural network architecture named ClusNet. This network is designed to study the trade-offs between the simplicity of instance-based methods and the accuracy of the more computational intensive learning methods. The features that make this network different from existing learning algorithms are outlined. A simple proof of convergence of the ClusNet algorithm is given. Experimental results showing the convergence of the algorithm on a specific problem is also presented. In this paper, ClusNet is applied to predict the temporal continuation of the Mackey-Glass chaotic time series. A comparison between the results obtained with ClusNet and other neural network algorithms is made. For example, ClusNet requires one-tenth the computing resources of the instance-based local linear method for this application while achieving comparable accuracy in this task. The sensitivity of ClusNet prediction accuracies on specific clustering algorithms is examined for an application. The simplicity and fast convergence of ClusNet makes it ideal as a rapid prototyping tool for applications where on-line learning is required.

Humans, Patient Care Team, Program Evaluation, Computer Systems, Documentation, and Hospital Information Systems

The implementation of a comprehensive bedside documentation system is a major project that demands careful analysis and planning. Since the cost of a typical bedside system can easily exceed $3 million, a design oversight could have disastrous effects on the benefits of the system.

Computer Graphics and Clinical Laboratory Information Systems

The computing strategy in our laboratories evolved from research in Artificial Intelligence, and is based on powerful software tools running on high performance desktop computers with a graphical user interface. This allows most tasks to be regarded as design problems rather than implementation projects, and both rapid prototyping and an object-oriented approach to be employed during the in-house development and enhancement of the laboratory information systems. The practical application of this strategy is discussed, with particular reference to the system designer, the laboratory user and the laboratory customer. Routine operation covers five departments, and the systems are stable, flexible and well accepted by the users. Client-server computing, currently undergoing final trials, is seen as the key to further development, and this approach to Pathology computing has considerable potential for the future.

Chemistry, Clinical, Critical Care, Humans, and Clinical Laboratory Information Systems

Interoperability may be defined as the ability of knowledge-based systems to function together in a symbiotic manner. Cooperativity implies interoperability but with the added benefit that the output quality of the cooperative network exceeds the overall performance of the participating sub-systems. A number of candidate architectures to support interoperability and cooperativity between medical knowledge-based systems in laboratory medicine domains are now becoming available. Using rapid prototyping techniques, we have demonstrated the feasibility of one of these approaches by carrying out pilot implementations in two unrelated laboratory medicine domains (an internal consistency checking system for validating patients' results in the laboratory and a system for generating alarms and alerts in high dependency units based on laboratory data). The results of this study are discussed in the context of the available techniques so as to provide a basis for further development of cooperative systems in laboratory medicine.

Computer Systems, Software, and Systems Integration

Computer scientists working in medical informatics have to face the problem that software offered by industry is more and more adopted for clinical use by medical professionals. A new challenge arises of how to combine commercial solutions with typical medical software that already exists for some years and proved to be reliable with these off-the-shelf solutions [1]. With the HERMES project, this new challenge was accepted and possible solutions to integrate existing legacy systems with state-of-the-art commercial solutions have been investigated. After a period of prototyping to assess possible alternative solutions, a system based on an indirect client-server model was implemented with help of the industry. In this paper, its architecture is described together with the most important features currently covered. Based on the HERMES architecture, both systems for clinical data analysis and patient care (cardiology) are currently developed.

Ambulatory Care Information Systems, Computer Communication Networks, and Computer Systems

PWS is a physician's workstation research prototype developed to explore the use of information management tools by physicians in the context of patient care. The original prototype was implemented in a client/server architecture using a broadcast message server. As we expanded the scope of the prototyping activities, we identified the limitations of the broadcast message server in the areas of scalability, security, and interoperability. To address these issues, we reimplemented PWS using the Open Software Foundation's Distributed Computing Environment (DCE). We describe the rationale for using DCE, the migration process, and the benefits achieved. Future work and recommendations are discussed.

Animals, Databases, Factual, Genome, Humans, Chromosome Mapping, and Database Management Systems

We are developing a laboratory notebook system known as the Genetics Deductive Database. Currently our prototype provides storage for biological facts and rules with flexible access via an interactive graphical display. We have introduced a formal basis for the representation and reasoning necessary to order genome map data and handle the uncertainty inherent in biological data. We aim to support laboratory activities by introducing an experiment planner into our prototype. The Genetics Deductive Database is built using new database technology which provides an object-oriented conceptual model, a declarative rule language, and a procedural update language. This combination of features allows the implementation of consistency maintenance, automated reasoning, and data verification.

Cockayne Syndrome pathology, Humans, Facial Expression, Image Processing, Computer-Assisted methods, Photography methods, and Physiognomy

As long ago as 1878 attempts have been made to define photographically the typical facial characteristics of persons exhibiting particular appearances or afflictions. State-of-the-art numerical computing techniques facilitate definition of highly accurate facial composites. Such images are devoid of ghosting caused by nonalignment of facial features. Composites can help to define the prototypical visual appearance of facial types and as such have applications in visual cognitive psychology and clinical imaging. This article describes the imaging process and discusses how clinical presentation of different diseases can be visualized using physiognomic information and how this has the potential to be developed as a diagnostic tool.

Artificial Intelligence, Computer Communication Networks, Database Management Systems, Delivery of Health Care, Humans, Information Storage and Retrieval, Software Design, User-Computer Interface, Computer Systems, Integrated Advanced Information Management Systems, and Software

The development of medical workstations for the support of patient care, the assessment of care, management support, and education is just at its beginning. During the Working Conference on the Health care Professional Workstation held in Washington DC, June 1993, several aspects of such workstations were discussed, but it was also recognized that prototyping or learning by experience could be a rich source to further promote the progress in this field. Eight such prototypes or already operational medical workstations were demonstrated and a preliminary user assessment was done to obtain a first insight in the advantages and the type of criteria of such evaluations. It was concluded that such assessments were of great value to (i) give feedback to the designers of medical workstations, (ii) indicate areas of strength and for further research, and (iii) to offer criteria to potential users of such workstations for making decisions on using such systems. The assessment criteria deal with functionality, architecture, user interfaces, communications and integration, and data and knowledge management.

Adolescent, Bone Plates, Computer Systems, Female, Humans, Lasers, Malocclusion surgery, Mandibular Neoplasms surgery, Microcomputers, Middle Aged, Osteotomy, Cephalometry instrumentation, Computer Simulation, Image Processing, Computer-Assisted instrumentation, Models, Anatomic, and Tomography, X-Ray Computed instrumentation

3-D-modelling of the skull is useful referring to improve diagnostics, for surgical planning and simulation of surgical procedure. Stereolithography is a constructive process producing a model by building it up layer by layer with plastic using an "ultraviolet" laser to catalyse the polymerization of a liquid plastic solution. This fast prototyping derives from using a new interface between a CT-Scanner and a SLA. By avoiding the tool path problems inherent in conventional computerdriven CNC milling machines we succeeded in producing closed cavities and even intraosseous course of vessels and nerves. The compact and smooth surface makes manual postprocessing unnecessary. By using a new software (interpolation +/- 0.25 mm) we could improve the accuracy. At our studies we found a maximum aberration of at least 0.25 mm.

Data Display, Database Management Systems, Software Design, and User-Computer Interface

We have looked at general descriptions and illustrations of several software development tools, such as tools for prototyping, developing DFDs, testing, and maintenance. Many others are available, and new ones are being developed. However, you have at least seen some examples of powerful CASE tools for systems development.

Humans, Skull anatomy histology, Image Processing, Computer-Assisted, Skull diagnostic imaging, and Tomography, X-Ray Computed

A study was undertaken to determine the dimensional accuracy of anatomical replicas derived from X-ray 3D computed tomography (CT) images and produced using the rapid prototyping technique of stereolithography (SLA). A dry bone skull and geometric phantom were scanned, and replicas were produced. Distance measurements were obtained to compare the original objects and the resulting replicas. Repeated measurements between anatomical landmarks were used for comparison of the original skull and replica. Results for the geometric phantom demonstrate a mean difference of +0.47 mm, representing an accuracy of 97.7-99.12%. Measurements of the skull produced a range of absolute differences (maximum +4.62 mm, minimum +0.1 mm, mean +0.85 mm). These results support the use of SLA models of human anatomical structures in such areas as pre-operative planning of complex surgical procedures. For applications where higher accuracy is required, improvements can be expected by utilizing smaller pixel resolution in the CT images. Stereolithographic models can now be confidently employed as accurate, three-dimensional replicas of complex, anatomical structures.

Computer Graphics, Computer Literacy, Hospital Records, Humans, Anesthesia, Attitude to Computers, Medical Records Systems, Computerized, and User-Computer Interface

Objective: The objective of our study was to assess the acceptability of a proposed user interface to visually interfaced computer-assisted anesthesia record (VISI-CAARE), before the application was begun. The user interface was defined as the user display and its user orientation methods.
Methods: We designed methods to measure user performance and attitude toward two different anesthesia record procedures: (1) the traditional pen and paper anesthetic record procedure of our hospital, and (2) VISI-CAARE. Performance measurements included the reaction speed (identifying the type and time of an event) and completion speed (describing the event). Performance also included accuracy of the recorded time of the event and accuracy of the description. User attitude was measured by (1) the physician's rating on a scale of 0 to 9 of the potential usefulness of computers in anesthesia care; (2) willingness to use the future application in the clinical environment; and (3) user suggestions for change. These measurements were used in a randomized trial of 21 physicians, of which data from 20 were available.
Results: After exposure to VISI-CAARE, the experimental subjects' ranking of computer usefulness in anesthesia care improved significantly (4.2 +/- 1.1 to 7.6 +/- 1.5, p = 0.0001), as did controls' (5.2 +/- 2.6 to 8 +/- 1.5, p = 0.0019). All the volunteers were willing to try the proposed prototype clinically, when it was ready. VISI-CAARE exposure was associated with faster and more accurate reaction to events over the traditional pen and paper machine, and slower and more accurate description of events in an artificial mock setting. VISI-CAARE 1.1 demonstrated significant improvements in both reaction speed and completion speed over VISI-CAARE 1.0, after changes were made to the user display and orientation methods.
Conclusion: With graphic user interface prototyping environments, one can obtain preliminary user attitude and performance data, even before application programming is begun. This may be helpful in revising initial display and orientation methods, while obtaining user interest and commitment before actual programming and clinical testing.

Data Display, Computers, Exhibitions as Topic, and Radiology

The computerized scientific exhibit (CSE) is gaining acceptance as a tool for delivering scientific information at meetings of radiologic societies. CSEs allow presentation of more material in a more space-efficient manner than do conventional exhibits, and the viewer can control the order and detail in which material is reviewed. As a disadvantage, currently, the radiologist must use a support team and learn new tools to create a CSE. The preparation and cost may also be greater. Meeting attendees must overcome a reluctance to use computers to benefit from a CSE. Creation of a CSE has design, production, and presentation phases. A team of content authors, software author, graphics acquisition person, and project manager works together through brainstorming, conceptual ordering, storyboarding, prototyping, and selection of authoring tools to design the exhibit. Production must include use of common word processing and image file formats, as well as standardization of image resolution. Accurate equipment specification is needed to ensure that the exhibit can be run on the equipment provided by the meeting organizers. In addition, some security steps are needed to prevent misuse of the exhibit. In addition to display at assemblies, the CSE can be made available to a larger audience by delivery on media such as compact disks and the Internet and can be continually modified as new material becomes available.

Decision Support Techniques, Expert Systems, Systems Integration, Artificial Intelligence, Clinical Laboratory Information Systems, Decision Making, Computer-Assisted, Programming Languages, and Reminder Systems

This article reviews the efforts of HBO & Company in the production of a first phase clinical alerting system based on the Arden Syntax. The alerting system was integrated with a clinical data repository and clinical workstation to process returning laboratory results. Investigations with expert systems resulted in a C language alerting system. GUI prototyping of an authoring environment led to a Smalltalk language authoring system. Future development is expected to broaden the system scope and address the evolution of the Arden Syntax.

Ear surgery, Humans, Prostheses and Implants, Diagnostic Imaging, Face anatomy histology, Face surgery, Skull anatomy histology, Skull surgery, and Surgery, Plastic

The acquisition, processing, and use of three-dimensional (3D) imaging provide new insights into normal and abnormal craniofacial anatomy. In this article, characteristics of CT and MRI scanning are reviewed along with the methods used to delineate tissues and produce 3D patient displays, including contouring, shaded surface, and volumetric processing. The use of 3D model fabrication for surgical planning is discussed with examples of the production of a custom CT-based auricle model and the use of rapid prototyping technology to create models for custom alloplastic implant surgery. The review concludes with some speculation about the future of 3D medical imaging as it will influence surgical training and practice over the coming decades.

Computer Security, General Surgery, Humans, Information Systems, User-Computer Interface, Computer Communication Networks, Computer Systems, Data Display, and Medical Records Systems, Computerized

We have experimented with developing a prototype Surgeon's Workstation which makes use of the World Wide Web client-server architecture. Although originally intended merely as a means for obtaining user feedback for use in designing a "real" system, the application has been adopted for use by our Department of Surgery. As they begin to use the application, they have suggested changes and we have responded. This paper illustrates some of the advantages we have found for prototyping with Web-based applications, including security aspects.

Computer-Assisted Instruction, Education, Medical, General Surgery education, Humans, Computer Simulation, Surgical Procedures, Operative, and Telemedicine

We are seeing the emergence of medical applications for virtual reality (VR). These include telepresence surgery, three-dimensional (3-D) visualization of anatomy for medical education, VR surgical simulators, and virtual prototyping of surgical equipment and operating rooms. Today, approximately 90% of the knowledge a physician requires can be obtained through electronic means, such as diagnostic sensors and imaging modalities, directly seeing the patient with a video camera for medical consultation, or using electronic medical records. In addition, with telepresence, a therapy can be effected electronically, regardless of the physical location of the patient. Therefore, it makes sense to send the electronic information or manipulation, rather than sending the patient or blood samples, to obtain tests or to produce a cure. In that these applications are mediated through the computer interface, they are the embodiment of VR as the major force for change in the field of medicine. The Green Telepresence Surgery System consists of two components, the surgical workstation and the remote worksite. At the remote site are a 3-D camera system and responsive manipulators with sensory input. At the workstation are a 3-D monitor and dexterous handles with force feedback. The next generation in medical education can learn anatomy from a new perspective by "flying" inside and around the organs, using sophisticated computer systems and 3-D visualization. The VR surgical simulator is a stylized recreation of the human abdomen with several essential organs. Using this, students and surgeons can practice surgical procedures with virtual scalpels and clamps. To support these advanced technologies, the operating room and hospital of the future will first be designed and tested in virtual reality, allowing multiple iterations of equipment and surgical rooms before they are actually built. Insofar as all these technologies are based on digital information, they are the building blocks for the digital physician of the 21st century.

Automation, Base Sequence, DNA, Satellite genetics, Frameshift Mutation, Markov Chains, Molecular Sequence Data, Sequence Deletion, Software, Algorithms, Models, Genetic, Mutation, Proteins chemistry, and Proteins genetics

Finite-state automata called transducers, which have both input and output, can be used to model simple mechanisms of biological mutation. We present a methodology whereby numerically-weighted versions of such specifications can be mechanically adapted to create string edit machines that are essentially equivalent to recurrence relations of the sort that characterize dynamic programming alignment algorithms. Based on this, we have developed a visual programming system for designing new alignment algorithms in a rapid-prototyping fashion.

The objective of this study is to establish a protocol for the technical and clinical evaluation of a workstation for the planning of stereotactic neurosurgical interventions that has been developed in the framework of a joint European research project. Although several such workstations have been proposed before, they lacked the final and most important step, that of clinical validation. They failed to rigorously prove that their product was useful. The authors present a new method that is applicable to the evaluation of a wide range of medical technologies. Their protocol basically assesses the clinical relevance of the user requirements that are at the root of the development of the new technology. The evaluation consists of two stages. During functional specification, iterative prototyping is used to establish the clinical requirements and to assure the quality of the final product. A case study design is used in a second stage that assesses the clinical usability. A before-after study gives a first indication of cost effectiveness and improvement of health care quality.

Computer Graphics, Heart diagnostic imaging, Humans, Magnetic Resonance Imaging, Reproducibility of Results, Respiratory System anatomy histology, Software, Software Design, Tomography, X-Ray Computed, Image Processing, Computer-Assisted methods, and User-Computer Interface

The utility of three-dimensional (3D) medical imaging is hampered by difficulties in extracting anatomical regions and making measurements in 3D images. Presently, a user is generally forced to use time-consuming, subjective, manual methods, such as slice tracing and region painting, to define regions of interest. Automatic image-analysis methods can ameliorate the difficulties of manual methods. This paper describes a graphical user interface (GUI) system for constructing automatic image-analysis processes for 3D medical-imaging applications. The system, referred to as IMPROMPTU, provides a user-friendly environment for prototyping, testing and executing complex image-analysis processes. IMPROMPTU can stand alone or it can interact with an existing graphics-based 3D medical image-analysis package (VIDA), giving a strong environment for 3D image-analysis, consisting of tools for visualization, manual interaction, and automatic processing. IMPROMPTU links to a large library of 1D, 2D, and 3D image-processing functions, referred to as VIPLIB, but a user can easily link in custom-made functions. 3D applications of the system are given for left-ventricular chamber, myocardial, and upper-airway extractions.

Hospital Records, Image Processing, Computer-Assisted, Software, and Radiotherapy, Computer-Assisted instrumentation

Purpose: We have developed a software tool for interactively verifying treatment plan implementation. The Electronic View Box (EVB) tool copies the paradigm of current practice but does so electronically. A portal image (online portal image or digitized port film) is displayed side by side with a prescription image (digitized simulator film or digitally reconstructed radiograph). The user can measure distances between features in prescription and portal images and "write" on the display, either to approve the image or to indicate required corrective actions. The EVB tool also provides several features not available in conventional verification practice using a light box.
Methods and Materials: The EVB tool has been written in ANSI C using the X window system. The tool makes use of the Virtual Machine Platform and Foundation Library specifications of the NCI-sponsored Radiation Therapy Planning Tools Collaborative Working Group for portability into an arbitrary treatment planning system that conforms to these specifications. The present EVB tool is based on an earlier Verification Image Review tool, but with a substantial redesign of the user interface. A graphical user interface prototyping system was used in iteratively refining the tool layout to allow rapid modifications of the interface in response to user comments.
Results: Features of the EVB tool include 1) hierarchical selection of digital portal images based on physician name, patient name, and field identifier; 2) side-by-side presentation of prescription and portal images at equal magnification and orientation, and with independent grayscale controls; 3) "trace" facility for outlining anatomical structures; 4) "ruler" facility for measuring distances; 5) zoomed display of corresponding regions in both images; 6) image contrast enhancement; and 7) communication of portal image evaluation results (approval, block modification, repeat image acquisition, etc.).
Conclusion: The EVB tool facilitates the rapid comparison of prescription and portal images and permits electronic communication of corrections in port shape and positioning.

Germany, Hospitals, University, Humans, Hospital Information Systems, and Medical Records Systems, Computerized

We demonstrate an Ethernet based local area network (LAN) with clinical workstations (Apple Macintosh). The patient archiving and documentation system (PADS) represents a computerized patient record system presently used in a university hospital's ICU, CCU, and oncology unit [1]. Since 1990, over 100 users have documented more than 6,000 patient admissions, equaling 30% of all inpatient admission in our hospital. Taking full advantage of the macintosh based graphical user interface (GUI), our system enables nurses and doctors to perform the following tasks: admission, medical history taking, physical examination, generation of problem lists and follow up notes, access to laboratory data and reports, and the semiautomatic generation of a discharge summary including full word processor capabilities. Furthermore, the system offers rapid, consistent, and complete automatic encoding of diagnoses following the International Classification of Disease (ICD - 9 CM; WHO). The system has links to other educational programs such as cardiac auscultation and image analysis. A MEDLINE literature search through a CD-ROM based system can be performed from within the system. CD-ROM based medical textbooks can be accessed as well. Users can customize their working environment and use any commercially available macintosh programs from within the main application. Additional options include: automatic background monitoring of users learning behavior, analyses and graphical display of numerous epidemiological, and healthcare related problems. Furthermore, sound and digital video can be recorded in our system. E had initially developed a relational database 4GL development tool in the rapid prototyping phase, and have since completed the next step of development: rewriting the complete application using C++ and Oracle. The user interface has hardly changed, maintaining the "look & feel" of the initial application and introducing the performance of a professional relational database management system (RDBMS). This system represents one in a line of modular departmental models which are being integrated to form a decentralized hospital information system (HIS) at the University of Munich. The proposed theater-style demonstration will walk the audience through the system simulating a true patient admission and work up.

Ambulatory Care organization administration, California, Disease classification, Humans, Insurance, Major Medical, Software Design, Vocabulary, Controlled, and Medical Records Systems, Computerized

To practice medicine in the near future, health care providers in the USA need an information infrastructure they do not yet have. We offer a contribution from social science research to discussions of current medical records practices and how health care activity systems may be transformed by the advent of electronic health records. The goal of the paper is to set forth a framework that connects over-arching questions concerning medical informatics systems development with the practical, cultural and conceptual issues involved in transitions from handwritten and other free text documentation to structured entry of medical records to build patient profiles. The research is broadly framed by an interest in how reciprocal modifications of the design and use of an electronic health record are negotiated in an iterative prototyping project. It is conducted as part of a complex multi-disciplinary research and development effort to create an electronic health record prototype for use in the integrated health care delivery environment of the Southern California Kaiser Permanente Medical Care Program.

Humans, Aerospace Medicine, Electronic Data Processing, Military Medicine, and Optometry

Background: Military optometry is experiencing changes at an unprecedented rate. Despite decreased staffing and budgets, the military must deal with more complicated deployment requirements as it takes on more humanitarian missions. New and emerging technologies, particularly automated information systems, will enhance its ability to meet these challenges.
Methods: Workgroups consisting of Army, Navy, and Air Force optometrists are developing operational strategies to meet future demands, employing 1) analysis to identify opportunities for business process improvement, 2) software prototyping to elicit and test automated system concepts and 3) functional economic analysis to evaluate the costs and benefits of automated information technologies.
Results: The workgroups have developed an operational concept that incorporates the development of a comprehensive Defense Vision Information System (DVIS). The DVIS is an automated information system that supports five general functional areas: 1) deployment readiness, 2) clinical examinations, 3) vision conservation (preventive medicine), 4) resource management, and 5) expert referencing. A full-scope DVIS will require integration with other military systems such as personnel, logistics, and existing hospital information systems.
Conclusions: Technology will enable the military to expand the scope and nature of optometry services through automation. The ultimate goal of automation is to support providers through efficient clinical operation and quick access to quality information for decision making. Eye care providers and patients will benefit as we use technology to optimize quality and cost effectiveness in the wartime and peacetime delivery of primary eye care.

Aerospace Medicine, Auditory Perception, Computer Graphics, Computer Peripherals, Computer Simulation, Data Display, Environment Design, Humans, Military Personnel psychology, Touch physiology, Visual Perception physiology, Aircraft, Electroencephalography instrumentation, Signal Processing, Computer-Assisted, and User-Computer Interface

The term Fusion Interface is defined as a class of interface which integrally incorporates both virtual and non-virtual concepts and devices across the visual, auditory and haptic sensory modalities. A fusion interface is a multi-sensory virtually-augmented synthetic environment. A new facility has been developed within the Human Engineering Division of the Armstrong Laboratory dedicated to exploratory development of fusion-interface concepts. One of the virtual concepts to be investigated in the Fusion Interfaces for Tactical Environments facility (FITE) is the application of EEG and other physiological measures for virtual control of functions within the flight environment. FITE is a specialized flight simulator which allows efficient concept development through the use of rapid prototyping followed by direct experience of new fusion concepts. The FITE facility also supports evaluation of fusion concepts by operational fighter pilots in a high fidelity simulated air combat environment. The facility was utilized by a multi-disciplinary team composed of operational pilots, human-factors engineers, electronics engineers, computer scientists, and experimental psychologists to prototype and evaluate the first multi-sensory, virtually-augmented cockpit. The cockpit employed LCD-based head-down displays, a helmet-mounted display, three-dimensionally localized audio displays, and a haptic display. This paper will endeavor to describe the FITE facility architecture, some of the characteristics of the FITE virtual display and control devices, and the potential application of EEG and other physiological measures within the FITE facility.

Electrolysis, Image Processing, Computer-Assisted, Lasers, Models, Dental, Computer-Aided Design, Dental Polishing methods, Dental Prosthesis Design, Dental Prosthesis, Implant-Supported, and Titanium

Traditional laboratory techniques are being supplemented by modern precision technologies to solve complex restorative problems. Electrical discharge machining combined with laser scanning and computer aided design-computer aided manufacturing can create very precise restorations without the lost wax method. A laser scanner is used to create a three-dimensional polyline data model that can then be converted into a stereolithography file format for output to a stereolithography apparatus or other rapid prototyping device. A stereolithography-generated model is used to create an electric discharge machining electrode via copper electroforming. This electrode is used to machine dental restorations from an ingot of titanium, bypassing the conventional lost wax casting process. Retaining screw access holes are machined using conventional drilling procedures, but could be accomplished with electric discharge machining if desired. Other rapid prototyping technologies are briefly discussed.

Adult, Child, Preschool, Computer Graphics instrumentation, Female, Fibroma, Ossifying surgery, Humans, Male, Middle Aged, Software, Therapy, Computer-Assisted instrumentation, Computer Simulation, Facial Asymmetry surgery, Image Processing, Computer-Assisted instrumentation, Jaw Neoplasms surgery, Malocclusion surgery, Maxillofacial Injuries surgery, Mouth Neoplasms surgery, and Tomography, X-Ray Computed instrumentation

Stereolithography (SLA), a rapid prototyping technique, was introduced in 1991 at the Clinic for Maxillofacial Surgery in Vienna and was adapted, in cooperation with the company Laserform, for our clinical requirements. As a refinement to physical models milled out of polyurethane, which had been used since 1989, this technique offered new applications for preoperative planning in craniomaxillofacial surgery. The proportions of these 3D models correspond 1:1 to the patients dimensions, with a possible accuracy of 0.25 mm. Since 1992 stereolithography has been used in 124 cases, primarily in traumatology, tumor surgery and in craniofacial surgery.

Automation economics, Costs and Cost Analysis, Humans, Language, United States, Vocabulary, Speech, Speech Perception, Telecommunications trends, Telephone economics, User-Computer Interface, and Voice

As the telecommunications industry evolves over the next decade to provide the products and services that people will desire, several key technologies will become commonplace. Two of these, automatic speech recognition and text-to-speech synthesis, will provide users with more freedom on when, where, and how they access information. While these technologies are currently in their infancy, their capabilities are rapidly increasing and their deployment in today's telephone network is expanding. The economic impact of just one application, the automation of operator services, is well over $100 million per year. Yet there still are many technical challenges that must be resolved before these technologies can be deployed ubiquitously in products and services throughout the worldwide telephone network. These challenges include: (i) High level of accuracy. The technology must be perceived by the user as highly accurate, robust, and reliable. (ii) Easy to use. Speech is only one of several possible input/output modalities for conveying information between a human and a machine, much like a computer terminal or Touch-Tone pad on a telephone. It is not the final product. Therefore, speech technologies must be hidden from the user. That is, the burden of using the technology must be on the technology itself. (iii) Quick prototyping and development of new products and services. The technology must support the creation of new products and services based on speech in an efficient and timely fashion. In this paper I present a vision of the voice-processing industry with a focus on the areas with the broadest base of user penetration: speech recognition, text-to-speech synthesis, natural language processing, and speaker recognition technologies. The current and future applications of these technologies in the telecommunications industry will be examined in terms of their strengths, limitations, and the degree to which user needs have been or have yet to be met. Although noteworthy gains have been made in areas with potentially small user bases and in the more mature speech-coding technologies, these subjects are outside the scope of this paper.

Biomedical Engineering economics, Biomedical Engineering instrumentation, Computer-Aided Design, Costs and Cost Analysis, Electrocardiography, Ambulatory economics, Electronics, Medical economics, Electronics, Medical instrumentation, Equipment Design, Humans, Medical Laboratory Science economics, Medical Laboratory Science instrumentation, Software, Electrocardiography, Ambulatory instrumentation, and Signal Processing, Computer-Assisted instrumentation

Field Programmable Gate Arrays (FPGAs) allow digital circuitry to be integrated on to a single device without the long time penalty incurred with mask programmable Application Specific Integrated Circuits (ASICs). This makes FPGA technology an attractive option to engineer involved in designing digital circuitry where space is at a premium. Furthermore, the relatively low cost of FPGAs at low volume, compared to mask programmable ASICs make them an excellent prototyping option for designers who are considering low cost volume production with mask programmable ASICs. There are several different types of FPGAs available which thus creates confusion for prospective users uncertain of their relative benefits. This paper serves as an introduction to FPGA technology and the stages involved in implementing a design, via the application of an Actel FPGA to the development of an ambulatory long term electrocardiogram (ECG) based RR interval recorder.

Humans, Larynx, Artificial, Tomography, X-Ray Computed, Trachea anatomy histology, Trachea diagnostic imaging, Models, Biological, and Tracheostomy

The availability of an accurate three-dimensional (3-D) model of the tracheostoma and trachea of the laryngectomy patient would be of great help in prototyping of endotracheal prostheses. Stereolithography has been described for skull and jaw models but never for soft-tissue reconstructions of the trachea. CT was performed on tracheostomas of 8 patients. The CT data were used to make 3-D models by means of stereolithography. Inverted CT data were used to create air contour models of the same tracheostomas. Eight soft-tissue and 8 air contour models were reconstructed from CT data, showing accuracy and great detail. In this paper we present a previously unreported application of the stereolithography technique. Measurements and prosthesis prototyping, which are impossible to perform on tracheostomas in patients, can now be executed safely. We are using the 3-D tracheostoma models in our research project to develop an endotracheal fixation method for tracheostomal valves.

Computer Security, Equipment Failure, Software, Computer Communication Networks, and Computer Systems

SQLGEN is a framework for rapid client-server relational database application development. It relies on an active data dictionary on the client machine that stores metadata on one or more database servers to which the client may be connected. The dictionary generates dynamic Structured Query Language (SQL) to perform common database operations; it also stores information about the access rights of the user at log-in time, which is used to partially self-configure the behavior of the client to disable inappropriate user actions. SQLGEN uses a microcomputer database as the client to store metadata in relational form, to transiently capture server data in tables, and to allow rapid application prototyping followed by porting to client-server mode with modest effort. SQLGEN is currently used in several production biomedical databases.

Face anatomy histology, Face diagnostic imaging, Humans, Image Processing, Computer-Assisted, Radiography, Skull anatomy histology, Skull diagnostic imaging, Computer Simulation, Diagnostic Imaging methods, Face surgery, Skull surgery, and Surgery, Plastic

Via an inverse approach to that of the Renaissance painter's treatment of perspective, the third dimension must be obtained from flat radiological information in order to reconstitute (virtually and materially) the volumes which it analyses. These images are analysed mathematically by computer. The applications are and will be numerous, especially in cranio-maxillo-facial surgery. Surgical simulation, without claiming to assess their soft tissue repercussions, section and virtually reposition bone segments: symmetrization and correction of hypotrophy are easy to visualize; computer-assisted surgical teaching applications (endoscopic surgery) are discussed. Multimodal images superimpose information from various sources: operative views and pre-recorded images are available to the surgeon and guide him in his "surgical navigation". Prototyping of skeletal anatomical specimens (prior to tumour or soft tissue specimens) provides the therapist with a precise preoperative spatial configuration of the abnormalities to be corrected, and the reconstructions to be performed. These developments, and others to come, are the sole objective of 3D imaging, beautiful in itself, but ineffective alone.

Software Design, Computer Communication Networks standards, Hospital Information Systems standards, Software standards, and Systems Integration

Componentized software promises easier, more fine-grained integration of disparate software systems. Variations of the technology can help to achieve tight coupling among disparate programs on the clinical workstation or across wide area networks. HL7 members have been designing extensions to the protocol for the exchange of healthcare information using Microsoft OLE and CORBA technologies. Extensive prototyping has been performed, including the simultaneous interconnection of sixteen different vendor systems exchanging demographic data and lab results. The first release of this standard will be notable in that the specifications for OLE and CORBA will be entirely isomorphic, they will be based directly, on HL7 version 2.3, and they may easily be implemented in systems that are not written using object-oriented programming tools. As HL7 version 3 is developed on an object-oriented model of healthcare information, the same approach will be used so information about the objects may be shared using CORBA and OLE.

Computer Graphics, Computer Systems, Humans, Hypermedia, Image Processing, Computer-Assisted, User-Computer Interface, Brain Mapping, Computer Communication Networks, and Software

The Web provides a rapid prototyping environment for building platform-independent graphical user interfaces. A Web-based console can be implemented as a suite of CGI scripts that generate HTML code, manipulate files, execute system commands, and invoke external tools. Often these tools share data by reading and writing flat files, which must be explicitly maintained by the CGI programmer. In a repository system, meta-data about each file object are maintained in a database, and access to all data is regulated by a layer of control services. This paper describes the design and implementation of a Web-based Repository Manager (WRM), which provides an application programmer's interface for controlling applications, generating HTML documents, handling Web forms, and managing multi-media data. The WRM is being used to develop a console for the Brain Mapping Framework, a system for visualizing cortical stimulation data obtained during neurosurgery.

General Surgery, Internship and Residency, Methods, Software, Systems Integration, Attitude to Computers, Computer Communication Networks, Computer Systems, Hospital Information Systems statistics numerical data, and Medical Records Systems, Computerized statistics numerical data

Construction of applications using the World Wide Web architecture and Hypertext Markup Language (HTML) documents is relatively simple. We are exploring this approach with an application, called PolyMed now in use by surgical residents for one year. We monitored use and obtained user feedback to develop new features and eliminate undesirable ones. The system has been used to keep track of over 4,200 patients. We predicted, several advantages and disadvantages to this approach to prototyping clinical applications. Our experience confirms some advantages (ease of development and customization, ability to exploit non-Web system components, and simplified user interface design) and disadvantages (lack of database management services). Some predicted disadvantages failed to materialize (difficulty modeling a clinical application with hypertext and inconveniences associated with the "connectionless" nature of the Web). We were disappointed to find that while integration of external Web applications (such as Medline) into our application was easy, our users did not find it useful.

Facility Design and Construction, Humans, Computer Simulation, Image Processing, Computer-Assisted instrumentation, Operating Rooms, and User-Computer Interface

Over the past five years, MITRE has developed rapid 3D modeling and immersive environment capabilities that supports the application of virtual environment technology to many traditional and non-traditional domains [1]. This paper provides background information on these capabilities and describes the application of this technology to the experimental design prototyping of operating rooms of the future and to the design and retrofit of existing or proposed medical facilities. These capabilities employ contemporary commercial hardware and software and exploit stereoscopic projection displays and headsets. A unique user interface facilitates object manipulation within these immersive environments and addresses two key areas: 1) Visualization of the contents on the model server or library in a catalog form; and 2) Natural interaction and immersion of the user with the visualized catalog and selected visualized objects in a 3D synthetic environment. A brief discussion of two developing applications of this technology will be presented. In one application example, the modeling environment can be used to synthesize physical replicas (potentially full stereo scale) of actual surgical rooms used for training of medical personnel. Alternatively, it can be employed as the infrastructure for a new form of collaborative interactive visualization, namely, telesurgery. In another example, the rapid modeling capability provides designers, architects and medical personnel with a means of rapidly developing synthetic renderings of (potentially interactive and remotely operative) proposed medical facilities prior to construction. We also discuss key issues needing to be resolved for successful model interchange.

Computer Communication Networks, Humans, Microscopy instrumentation, Software, Systems Integration, Image Processing, Computer-Assisted instrumentation, and Telepathology instrumentation

The Laboratory for Biomedical Informatics (LBMI) has developed a digital microscope control module incorporated into an image analysis system. This is now equipped with an ISDN switch box for linking up with a remote computer-based station for delivering histopathological services. The FRAME, client/server integrated software, was developed to initiate the communication link, adjust the microscope settings, acquire and transmit images. This LBMI telepathology initiative employs simple solutions to arrive at the point of prototyping and demonstrating the state of the art on the one hand and encountering the prevailing problems in order to deliberate on possible remedies on the other.

Two-photon excitation of carriers in boron E'-center-containing borosilicate glasses results in a photoencoding of selectively etchable regions. Using a turbulent etching process followed by polishing, we have demonstrated a number of patterning capabilities for microtechnology applications such as ultrafast capillary electrophoresis chips and rapid prototyping of diffractive optical elements.

Present-day computational fluid dynamics (CFD) techniques can be used to analyze the behavior of fluid flow in a variety of pumps. CFD can be a powerful tool during the design stage for rapid virtual prototyping of different designs, analyzing performance parameters, and making design improvements. Computational flow solutions provide information such as the location and size of stagnation zones and the local shear rate. These parameters can be correlated to the extent of hemolysis and thrombus formation and are critical to the success of a blood pump. CFD-ACE, an advanced commercial CFD code developed by CFD Research Corporation, has been applied to fluid flows in rotary machines, such as axial flow pumps and inducers. Preprocessing and postprocessing tools for efficient grid generation and advanced graphical flow visualization are integrated seamlessly with CFD-ACE. The code has structured multiblock grid capability, non-Newtonian fluid treatment, a variety of turbulence models, and an Eulerian-Lagrangian particle tracking model. CFD-ACE has been used successfully to study the flow characteristics in an axial flow blood pump. An unstructured flow solver that greatly automates the process of grid generation and speeds up the flow simulation is under development.
(© 1996 International Society for Artificial Organs.)

Biocompatible Materials, Blood Flow Velocity physiology, Computer Simulation, Heart-Assist Devices adverse effects, Hemolysis, Pressure, Equipment Design trends, and Heart-Assist Devices standards

Present-day computational fluid dynamics (CFD) techniques can be used to analyze the behavior of fluid flow in a variety of pumps. CFD can be a powerful tool during the design stage for rapid virtual prototyping of different designs, analyzing performance parameters, and making design improvements. Computational flow solutions provide information such as the location and size of stagnation zones and the local shear rate. These parameters can be correlated to the extent of hemolysis and thrombus formation and are critical to the success of a blood pump. CFD-ACE, an advanced commercial CFD code developed by CFD Research Corporation, has been applied to fluid flows in rotary machines, such as axial flow pumps and inducers. Preprocessing and postprocessing tools for efficient grid generation and advanced graphical flow visualization are integrated seamlessly with CFD-ACE. The code has structured multiblock grid capability, non-Newtonian fluid treatment, a variety of turbulence models, and an Eulerian-Langrangian particle tracking model. CFD-ACE has been used successfully to study the flow characteristics in an axial flow blood pump. An unstructured flow solver that greatly automates the process of grid generation and speeds up the flow simulation is under development.

Anatomy, Cross-Sectional, Humans, Quality Control, Software, User-Computer Interface, Computer Communication Networks, Image Processing, Computer-Assisted, and Radiology Information Systems

Internet access to mixed text/image databanks is finding application in the medical world. An example is a database of medical X-rays and associated data consisting of demographic, socioeconomic, physician's exam, medical laboratory and other information collected as part of a nationwide health survey conducted by the government. Another example is a collection of digitized cryosection images, CT and MR taken of cadavers as part of the National Library of Medicine's Visible Human Project. In both cases, the challenge is to provide access to both the image and the associated text for a wide end user community to create atlases, conduct epidemiological studies, to develop image-specific algorithms for compression, enhancement and other types of image processing, among many other applications. The databanks mentioned above are being created in prototype form. This paper describes the prototype system developed for the archiving of the data and the client software to enable a broad range of end users to access the archive, retrieve text and image data, display the data and manipulate the images. System design considerations include; data organization in a relational database management system with object-oriented extensions; a hierarchical organization of the image data by different resolution levels for different user classes; client design based on common hardware and software platforms incorporating SQL search capability, X Window, Motif and TAE (a development environment supporting rapid prototyping and management of graphic-oriented user interfaces); potential to include ultra high resolution display monitors as a user option; intuitive user interface paradigm for building complex queries; and contrast enhancement, magnification and mensuration tools for better viewing by the user.

The effect of key shape on a touchscreen simulation of a flat touch-sensitive keypad was investigated by rapid prototyping. A software prototype was developed of a hardware keypad that controlled chemical analysis equipment. The prototype was used to answer some basic ergonomics questions concerning the design of the device keys. In a target selection task, keys shaped as equilateral triangles were most precise, and least precise was a compound shape comprising of a rectangular lower part and a triangular 'hat' as the upper part. No significant differences in the times taken to complete the task were found. It is suggested that the use of a touchscreen prototype is suitable when designing flat-keypad layouts. Due to the visual nature of flat keypad use, where perception of the target must counter reduced tactile feedback, the design of shapes to aid the selection of keys is of paramount importance. It is concluded that rapid prototyping of hardware with graphical designs and touchscreens is a powerful tool for the ergonomic design of interfaces.

Cholesterol, Guideline Adherence, Humans, Computer Communication Networks, Database Management Systems, Hyperlipidemias therapy, and Practice Guidelines as Topic

DMS is a Web-based disease-management system, which facilitates easy access for users and close connection to hospital information systems, based on clinical practice guidelines. Currently we are prototyping DMS in the area of hyperlipidemia management. However our approach is general. For each office visit, DMS generates an encounter form with recommendations based on the National Cholesterol Education Program (NCEP) guidelines. In between visits, DMS provides email notifications to clinicians about delinquent laboratory studies and recommendations for patient management based on recently available information. By reviewing previous efforts for implementing NCEP guidelines and some of the pitfalls that were encountered, we first constructed DMS for hyperlipidemia management. A detailed description of DMS is provided in this paper.

Computer Graphics, Models, Molecular, Proteins chemistry, User-Computer Interface, Computer Systems, Molecular Structure, and Software

A new software configuration method using plug-in style components was established for the tool with the incremental development of software used in protein structural study. Our memory database provides the interface of data and functions among plug-in modules and its host program. A molecular structure browser program was developed together with several plug-in modules on our programming library that maintains graphics portability and user interfaces. This plug-in software architecture is generally useful for large-scale software development and for prototyping parts of the system.

Adult, Aged, Female, Humans, Image Processing, Computer-Assisted, Male, Middle Aged, ROC Curve, Radiography, Calcaneus diagnostic imaging, Calcaneus injuries, and Fractures, Bone diagnostic imaging

The purpose of this study was to evaluate and compare the diagnostic performance of stereolithography vs workstation-based three-dimensional (3D) reformations in intra-articular calcaneal fractures. A total of 30 intra-articular calcaneal fractures were examined using standard radiographs, coronal CT scans, and 2D and 3D reformations. The CT data were transferred to an outside institution, and stereolithograms were produced from photopolymer resin employing a laser beam system. 3D reformations and stereolithograms were analyzed in a blinded fashion by two staff radiologists. Receiver-operating-characteristic (ROC) curves were obtained for six clinically significant fracture components. Standard radiographs, coronal CT scans, and 2D reformations served as the standard of reference. The area under the ROC curves for 3D reformations and stereolithograms were 1.0 and 0.98 for abnormal tuber angles, 0.91 and 0.91 for anterior and middle talo-calcaneal joint involvement, 0. 90 and 0.95 for involvement of the posterior talo-calcaneal joint, 0. 65 and 0.78 for the presence of a lateral bulge, 0.80 and 0.81 for the involvement of the calcaneocuboidal joint, and 0.62 and 0.67 for the presence of a "tongue-type" fracture. No statistically significant difference was demonstrated for the two methods (Wilcoxon signed-rank test, p = 0.138). Based on our results stereolithograms did not prove to be statistically superior to workstation-based 3D reformations. Stereolithograms may still be useful for teaching purposes and for surgical planning at a thinking-efficacy level.

Humans, Optical Illusions, Psychophysics, Software Design, Computer Terminals, Data Display, Pattern Recognition, Visual, Software, and User-Computer Interface

Psychophysical researchers often need to vary stimuli parametrically during experimental design. The X Portable Interface Package, a set of free software libraries for X-Windows, provides a suitable platform for quickly prototyping visual stimuli and administering simple experiments.

Adult, Biomedical Engineering instrumentation, Biomedical Engineering methods, Cephalometry instrumentation, Cephalometry methods, Craniosynostoses pathology, Evaluation Studies as Topic, Femur anatomy histology, Hip Prosthesis, Humans, Image Processing, Computer-Assisted instrumentation, Infant, Magnetic Resonance Imaging methods, Tomography, X-Ray Computed methods, Image Processing, Computer-Assisted methods, Lasers, and Models, Anatomic

Rapid prototyping techniques, originally developed for building components from computer aided designs in the motor industry, are now being applied in medicine to build models of human anatomy from high resolution multiplanar imaging data such a computed tomography (CT). The established technique of stereolithography and the more recent selective laser sintering (SLS), both build up an object layer by layer. Models have applications in surgical planning, for the design of customised implants and for training. Preliminary experience of using the SLS technique for medical applications is described, addressing questions regarding image processing, data transfer and manufacture. Pilot models, built from nylon, included two skills (a child with craniosynoslosis and an adult with hypertetorism) and a normal femur which was modelled for use in a bioengineering test of an artificial hip. The dimensions of the models were found to be in good agreement with the CT data from which they were built-for the child's skull the difference between the model and the CT data was less than 1.0 +/- 0.5 mm in each direction. Our experience showed that, with care, a combination of existing software packages may be used for data conversion. Ideally, image data of high spatial resolution should be used. The pilot models generated sufficient clinical interest for the technique to be pursued in the orthopaedic field.

Computer Graphics, Humans, Image Processing, Computer-Assisted, Mandible diagnostic imaging, Pilot Projects, Reproducibility of Results, Mandible anatomy histology, Models, Anatomic, and Tomography, X-Ray Computed methods

We investigate the accuracy of complex anatomical replicas derived from X-ray computed tomography data linked to the rapid prototyping technique of stereolithography. Data processing by specific softwares (segmentation, three-dimensional interpolation) allows direct interfacing with the stereolithography apparatus to build a resin replica with reproduction of internal cavities. Our preliminary results about surface and dimensional accuracies suggest that the reproduction of complex anatomical structures by stereolithography is reliable enough to be used for surgical planning, for custom-made implants and for surgical anatomy teaching.

Anesthesiology, Biomedical Engineering education, Humans, Laparoscopy, Computer-Aided Design, Ergonomics, Monitoring, Intraoperative instrumentation, and User-Computer Interface

There is a growing consensus that human factors issues for anesthesiologists, surgeons, and other operating room personnel require serious attention. We have established a program of collaboration between the University of California Davis Medical Center Departments of Anesthesiology and Surgery and the California State University Sacramento Biomedical Engineering Program to address ergonomic problems in anesthesiology and surgery using a Virtual Instrumentation Laboratory. A 17-workstation Virtual Instrument Laboratory using LabVIEW software on Power Macintosh platforms permits rapid prototyping of medical monitor displays as well as rapid development of data acquisition and processing circuits for physiologic data collection. The Virtual Instrument Lab has been used for three Master's thesis projects and a BME course titled Human Factors in the Design of Medical and Assistive Technology. Course projects have included: 1) The design of novel physiologic data displays for potential use in anesthesia workstations, and 2) The measurement of surface electromyographic signals and heart rate variability to investigate the physical and mental workload of performing laparoscopic surgery. The Virtual Instrument Lab allows BME students to investigate relatively complex human factors issues in anesthesiology and surgery in a short time span.

Computer Simulation, Equipment Design, Humans, Surgical Procedures, Operative trends, Image Processing, Computer-Assisted, Surgical Equipment trends, Surgical Procedures, Operative methods, and User-Computer Interface

In cooperation with the Max-Delbrück-Centrum/Robert-Rössle-Klinik (MDC/RRK) in Berlin, the Fraunhofer Institute for Computer Graphics is currently designing and developing a scenario for the operating room of the future. The goal of this project is to integrate new analysis, visualization and interaction tools in order to optimize and refine tumor diagnostics and therapy in combination with laser technology and remote stereoscopic video transfer. Hence, a human 3-D reference model is reconstructed using CT, MR, and anatomical cryosection images from the National Library of Medicine's Visible Human Project. Applying segmentation algorithms and surface-polygonization methods a 3-D representation is obtained. In addition, a "fly-through" the virtual patient is realized using 3-D input devices (data glove, tracking system, 6-DOF mouse). In this way, the surgeon can experience really new perspectives of the human anatomy. Moreover, using a virtual cutting plane any cut of the CT volume can be interactively placed and visualized in realtime. In conclusion, this project delivers visions for the application of effective visualization and VR systems. Commonly known as Virtual Prototyping and applied by the automotive industry long ago, this project shows, that the use of VR techniques can also prototype an operating room. After evaluating design and functionality of the virtual operating room, MDC plans to build real ORs in the near future. The use of VR techniques provides a more natural interface for the surgeon in the OR (e.g., controlling interactions by voice input). Besides preoperative planning future work will focus on supporting the surgeon in performing surgical interventions. An optimal synthesis of real and synthetic data, and the inclusion of visual, aural, and tactile senses in virtual environments can meet these requirements. This Augmented Reality could represent the environment for the surgeons of tomorrow.

Humans, Male, Middle Aged, Models, Anatomic, Temporal Bone anatomy histology, Cochlear Implants, Computer Simulation, Image Processing, Computer-Assisted methods, Temporal Bone diagnostic imaging, and Tomography, X-Ray Computed

Rapid prototyping (RP) technique allows automatic fabrication of 3D model parts. This method was applied to make a temporal bone model before cochlear implant surgery. A helical CT scan is used to acquire high resolution data from the middle and the inner ear of the patient. From the scanning data bone structures and soft tissues can be separated because their different grayscale pixel values. By using a guided image processing tool the desired parts of the anatomy can be extracted and 3D data created. The segmented data are processed to the form suitable for creating a high accuracy RP model. The RP model is made in the stereolithography (SLA) process by means of a computer guided HeCd laser beam inducing polymerisation of acrylic solution as it passes layer by layer over the surface of the polymer solution. In this prototype model the anatomy of the temporal bone can be clearly visualised, including, e.g., mastoid cells, tympanic cavity, bony canal of facial nerve, and round and oval windows. The inner ear spaces including vestibule, semicircular canals and cochlear turn are also shaped. The transparent acrylic material allows bonelike mechanical handling. The RP model can be dissected and used in individual surgical planning and simulation prior to cochlear implantation.

Adolescent, CD-ROM, Female, Health Promotion, Humans, Male, Program Evaluation, Software, United Kingdom, Computer-Assisted Instruction, and Sex Education methods

This article describes an interactive prototyping model for development of four computer software modules for British youth on sexual issues. An iterative cycle of development, user review and feedback, and subsequent modification and retesting was used with approximately 150 young adults, with particular attention to presentation style, screen design, usability, relevance of material, enjoyment, and learning. The software was designed to be realistically accommodated in school settings, to be used as a reference tool by students working alone or in a group teaching situation. Feedback from youth and adults attests to the feasibility of development, implementation, and instructional usefulness. Interactive prototyping proved essential in the face of skepticism from teachers concerning young people's information needs and acceptance of a computerized educational approach.

Three-dimensional periodic microstructures of aluminum oxide, which are important for creating photonic band-gap structures (PBGs), were fabricated by laser rapid prototyping by means of laser-induced direct-write deposition from the gas phase. The structures consisted of layers of parallel rods forming a face-centered tetragonal lattice with lattice constants of 66 and 133 micrometers. These structures showed transmission minima centered around 4 terahertz (75 micrometers) and 2 terahertz (150 micrometers), respectively. PBGs will allow precise control of the optical properties of materials, including lasers without threshold.

Adult, Costs and Cost Analysis, Female, Humans, Male, Pelvic Bones surgery, Preoperative Care, Time Factors, Tomography, X-Ray Computed economics, Tomography, X-Ray Computed methods, User-Computer Interface, Computer Simulation, Models, Anatomic, and Pelvic Bones diagnostic imaging

X-ray or CT images allows only a limited three-dimensional orientation in presurgical planning. Especially for the planning of internal hemipelvectomies with custom-made endoprosthesis and for peri-acetabular osteotomies a high-grade orientation is necessary. This orientation is improved by a 3D CT-controlled manufactured 1:1 model of the pelvis. This enables and exact classification of defect and deformity, planning of resection planes, design of the suitable custom-made implant and simulation of the operation technique as preoperative quality control.

Child, Facial Asymmetry diagnostic imaging, Facial Asymmetry surgery, Facial Bones diagnostic imaging, Facial Bones injuries, Female, Humans, Image Processing, Computer-Assisted methods, Male, Computer-Aided Design, Facial Bones surgery, Magnetic Resonance Imaging, Models, Anatomic, and Tomography, X-Ray Computed

The rapid advances in computer technology, often driven by the demands of industry, have created new possibilities in surgery which previous generations of surgeons could only have imagined. Improved imaging with computerised tomography (CT) has been followed by magnetic resonance imaging (MRI) and, more recently, it has become possible to reformat the data as three-dimensional images. Computer technology has new moved forward with the advent of rapid prototyping techniques (RPT) which allow both the production of models of the hard tissues and custom-made prostheses from computerised scanning data. In this article we review the development and current technologies available in RPT and the applications of this advance in surgery and illustrate this with two case reports.

Equipment Design, Humans, Models, Anatomic, Patient Care Planning, Image Processing, Computer-Assisted instrumentation, Oral Surgical Procedures instrumentation, Plastic Surgery Procedures instrumentation, and Tomography, X-Ray Computed instrumentation

Our clinical results show that 3D model building is an excellent method for 3D preoperative planning. Dependent on the number of steps, however, there are many possibilities of failures. Standardization and quality control of data acquisition and industrial manufacturing must be recommended. This is especially important for stereolithography, as it is definitely more complex than the milling technique. One possibility seems to be the use of phantom models. Another factor is that the surgeon has to be involved in the essential steps of data analysis and segmentation. Based on our experience, the building of 3D CT skull models is a clinically efficient method that is mature enough for clinical use, but cannot yet be accepted as the clinical routine. Quality assurance is urgently necessary.

Humans, Diagnostic Imaging methods, Image Processing, Computer-Assisted, Microcomputers, and Software

A 32-bit PC-based 3D medical image processing software package is presented. Its basic functions are the display and manipulation of medical images and the inclusion of user-written processing routines in C language. This software runs on inexpensive hardware and is easy to learn. It means the current needs of many research teams working in medical image processing.

Anti-Inflammatory Agents, Non-Steroidal therapeutic use, Hip Prosthesis, Humans, Osteoarthritis, Hip etiology, Physical Therapy Modalities, and Osteoarthritis, Hip therapy

Osteoarthritis of the hip joint is due either to primary diseases of the articular cartilage or to secondary conditions leading to degenerative changes, for example, pre-arthritic deformities or arthropathies, so-called. Besides conservative treatment with non-steroidal anti-inflammatory drugs and physical therapy, treatment of pre-arthritic deformities by curative osteotomy continues to be of major importance. The introduction of the Rapid Prototyping method considerably improved the preoperative planning and orientation of such procedures. In the case of advanced coxarthrosis, total hip arthroplasty is used, in which, depending on bone biology, cementless procedures are now being employed in addition to the well-proven implantation with cement. Success depends not only on material and shape, but also to a high degree on the surface structure of these cementless implants. In particular three-dimensional interconnecting open-mesh surfaces enable differentiated anchoring of the prosthesis.

Child, Facial Asymmetry diagnostic imaging, Female, Humans, Mandible diagnostic imaging, Osteogenesis, Distraction methods, Radiography, Facial Asymmetry surgery, Mandible surgery, and Osteogenesis, Distraction instrumentation

A case is reported where the callus in a mandibular osteotomy site underwent distraction by means of an intra-oral device. The procedure was undertaken in a 9-year-old patient diagnosed with hemifacial microsomia type I. Using rapid prototyping from a radiographic scan of the facial skeleton an acrylic model was made upon which the intra-oral appliance was designed. The appliance produced an elongation of 11 mm which succeeded in correcting the skeletal asymmetry of the mandibular symphysis. The patient has been followed up for 7 months and the correction appears stable.

Biomedical Engineering, Computer-Aided Design, Female, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Middle Aged, Models, Anatomic, Prosthesis Design, Thorax anatomy histology, and Heart, Artificial

The failure of the orthotopic implantation of a totally implantable artificial heart (TAH) was due mainly to anatomic mismatches in the conduits of the conventional TAH system. To overcome this anatomic incompatibility, a custom design and fabrication process was designed using the rapid prototyping (RP) technique. After three dimensional reconstruction of magnetic resonance imaging of the thoracic cavity and vascular remnants of the recipient, study of anatomic fit was done using the reconstructed thoracic model and three dimensional computer aided design (CAD) model. The direction of the inflow and outflow conduits of the blood sac was changed with a Unigraphics CAD. The RP model of the designed chamber was fabricated and examined for anatomic compatibility. Through this approach, the minute directional mismatch of the inflow and outflow conduits was improved. Thus, a new custom designed moving actuator Korean TAH with CAD and RP techniques was developed.

Hip Joint diagnostic imaging, Humans, Mandible diagnostic imaging, Software, Tomography, X-Ray Computed instrumentation, Tomography, X-Ray Computed statistics numerical data, Models, Anatomic, and Tomography, X-Ray Computed methods

The visual three-dimensional (3D) reconstruction of CT findings has been used since the Seventies to design and plan complex surgical procedures. The availability of such models and the development of computer science have permitted, since the mid-Eighties, the medical use of rapid prototyping for anatomical modelling. We studied the technical steps of CT data processing for rapid prototyping and the dimensional and structural accuracy of replicas of skeletal components relative to the originals. A dried mandible and an arthrotic hip joint were compared with their stereolithographic replicas using the measurements made on CT images. The 3D graphic models were processed with a commercially available software and replicated with an SLA 250 stereolithographer (3D System Inc, Valencia CA, USA). Satisfactory morphologic agreement was found between the original and its replica. The mandibular replica exhibited dimensional errors ranging 0 to 4.03%, z-axis shortening and an increase in gonial angle, but with a reliable reproduction of details. The hip replica exhibited dimensional errors ranging .2% to 8.53%; it appeared to be less affected than the mandibular replica by geometrical distortion but it was less accurate in the reproduction of cancellous bone and arthrosis. The accuracy of the solid replicas depends, in the different manufacturing steps, on several factors, namely: during data acquisition, the accuracy and suitability of original data, depending in turn on equipment and examination parameters--especially the algorithm, acquisition time, gantry tilt and slice thickness; image thresholding and manipulation procedures during graphic model creation; data transfer, creation of the necessary supports and replica finishing during manufacturing; residual polymerization affected by environmental agents and preservation conditions during maintenance.

Computer Systems, Humans, Internet standards, Software standards, Systems Integration, Practice Guidelines as Topic, and Programming Languages

Much work has been done in the area of web-based clinical practice guidelines. Issues such as representation, description, architectures, and implementation have been explored previously. Most if not all of these web-based applications rely exclusively on HTML, the HyperText Markup Language. In the process of prototyping a guideline service to be used in a diabetes operations improvement project, we developed a model for a guideline engine that makes use of the Extensible Markup Language (XML), both as an interface to the engine and as a vehicle for delivering structured guideline content. We feel that XML may offer advantages in implementing guideline services that are difficult (if not impossible) to accomplish with HTML alone.

Cerebrospinal Fluid physiology, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Neurosurgery education, Patient Care Planning, Research, Resins, Synthetic, Rheology, Teaching Materials, Cerebral Ventricles anatomy histology, Computer-Aided Design, and Models, Anatomic

As part of our research into the fluid hydrodynamics of the human ventricular system, a fused deposition model of the human ventricular system was made using magnetic resonance imaging (MRI) data. This article describes the manufacturing of a positive cast of the ventricles as a first step in the construction of a hollow model. After decryption of the original MRI file (ACR-Nema format), the MRI slices were reassembled semiautomatically and a rapid prototyping station produced a resin model. Because of its ease and speed, this method harbors great potential for teaching purposes, research, and preoperative planning in complex three-dimensional soft tissue targets.