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269 Autopsy strategy with congenital heart disease under utilization of the results of the prenatal diagnostic Cornelia Tennstedt, R. Chaoui', P. Hufnagl, T.N. NguyenDobinsky* , M. Dietel Institut fur Pathologie, *Frauenklinik, Universitatsklinikum der Humboldt - Universitat zu Berlin, Campus Charite Mitte Aims: In the following contribution we propose an effective autopsy strategy for the diagnostic of congenital heart disease. It is based on the knowledge of the praenatal diagnostic and in particular on the specific sectional scans used for it. Methods: The knowledge about the prenatal representative sectional scans is the prerequisite for the post-mortem examination of the pathological findings of the respective heart malformation. The autopsy of the heart is performed in such a way that all possible sectional scans correlating to the ultrasonic are documented. The images are stored in an interdisciplinary case and image database: PIA image archiving system (Viewpoint GmbH, Germany), stereo microscope (Typ SzH 10, Olympus Opt Corp.) with color video camera (Sony 3 CCD DX930p). Results: An effective mode of operation is ensured during the autopsy, if a direct autopsy strategy is applied. Consequently the praenatal diagnoses can be checked for their correctness and may be discussed in the case of interdisciplinary deviations between the findings. The images with the correlating sectional scans of the pathological findings of the CHD between of ultrasound and autopsy are stored in an interdisciplinary digital image database and can be investigated at any time. Conclusions: At a center for perinatal medicine with the emphasis of CHD a quality assurance of the praenatal diagnostic can be only ensured, if the autopsy of the heart malformations is directly performed under knowledge of the praenatal findings. The documentation of the correlating sectional scans for ultrsound and autopsy findings is the basic for the discussion of the interdisciplinary findings.

271 MULTIMEDIAL DATA BASE AND MANAGEMENT SYSTEM FOR SELF-EDUCATION AND TESTING THE STUDENTS KNOWLEDGE ON PATIIOLOGY J. Szymas Department of Pathology, University of Medical Sciences, Poznan, Poland The composition assumed our experiences in creating and using multimedial data base of examination multiple choice test questions and management system, which is used for. This system is implemented on microcomputers compatible with ffiM PC and works in local area network (LAN) of our Department of Pathology. The test questions exceeded 2000 until now. The packet consists of the two functionally individual programs: ASSISTANT, which is dedicated for the administration of the relational data bases, configuration and parameterization of the system made by the teacher. Second program is EXAMINATOR which is the executive program for the students. These programs are implemented in the technique of pull-down menu, message and selection windows. This way make easier to be operated by students which are still inexperienced with microcomputers and operating system command. Our packed enables to use text files and add images to each question, which are adjusted to display on most of the standard graphics cards. Standard format of the notification files enables to elaborate the results in order to estimate the scale of answers, and to find correlation between the results. The notation boards allow to estimate the scale of question and answers. These functions are realized by another programs of this packed . This packed was created for self-education of the students and examining them concerning the configuration of the active data base defined previously by the ASSISTANT program. This system is used in our Department of Pathology for 7 years to verify student's knowledge. Along with the development of Internet and usefulness of WWW servers some of our data bases are located at the WWW site and available with the Internet browser. Internet make possible for us to teaching and examining at a distance as well as to share our data with other pathological departments.

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ELECTRONIC PUBLICATION IN PATIIOLOGY : RECENT DEVELOPMENTS K. Kayser, G. Kayser Abteilung fur Pathologie, Thoraxklinik, Heidelberg Aims: The future of a medical discipline is basically determined by its contribution to science. Communication and publication are major prerequisites for the scientific development of any medical discipline, especially pathology. Methods: The common procedures of conventional publication in pathology are described. They are characterized by a non-flexible structure and performance of any scientific aricle which usually contains an introduction, description ofthe used material and techniques, presentation of the results, discussion, and references. Paper-based presentation of images which are of major importance in pathology, is expensive. In addition, any article can be multiplied only by reprints which have to be ordered by the authors in advance. The readers of any article remain anonymous to the authors. Pre-publication reviewing is a duty ofthe editor in chief who has to select the appropriate reviewers and who is dependent upon their opinion. Results: Electronic publication in pathology has been proven to possess certain advantages compared to paper-written articles. The publication procedure is fast, reviewing can be performed without any influence of the editor in chief, presentation of color images is inexpensive and the images are of brilliant quality. New publication procedures can be performed. These include live presentation of any time-dependent functions (programs), interactive publication, active intervention of the reader, and automated search for readers who are working in fields related to that of the article. Conclusions: Electronic publication will probably influence the world of pathology. New ideas such as the PARIS project (automated and anonymous evaluation of scientific articles via the internet) are only first steps in the electronic area of scientific communication in pathology.

INTRA- AND EXTRANET: TRENDS FOR MEDICAL EDUCATION MAINZMODEL M. Otto, J. Kriegsmann, F. Bittinger, C.J. Kirkpatrick Institut fiIr Pathologie, Johannes Gutenberg Universitat Mainz Aims: The Internet technology known as World Wide Web (WWW) is rapidly growing as the most powerful medium of communication in this decade and it can be harnessed to dispense global, cost-effective, highquality, multimedia patient education material. The internet technology is rapidly invading the corporate networks and up to 180 million users will be connected to an intranet by the year 2000. The Intranet, combined with the extranet for not locally held material, is an important concept in educational information flow, not least because it can be set up with little trouble and be used easily. An Extranet-Intranet-LAN system is described as used in our Medical School environment of 20 staff and several hundred students. Materials and Methods: The technological basis for the "Mainz er Pathologie Netzwerk" is based on a Pentium PH 300 with an Omni-HTTPserver 2.01 which runs under Windows 98 for the intranet area and an Pentium PH 450 which runs under LINUX for the restricted extranet area. For the histological courses on general and systematic pathology an HTML based interactive learning environment was developed which deals with the demonstration of several entities with complete clinical, cross pathological and histological information, pictures and some multimedia components. Both on the internal as well as on the external server the students have access to the these materials using a standard browser software. In the intranet the students have the opportunity to use many additional information systems, such as multiple literature databases, as well as complete electronically published but licence restricted papers. Using the extranet area, the students have an unlimited access to the self developed pathological courses without the direct access to the restricted areas. ResultslDiscussion: The usage of the internet courses in pathology increased during the last year. The access rate during the last semester stood at approximately 1800 using the extranet line. The mail comments form the students are genarally positive and favour the expansion of the electronic teaching material. The intranet usage will be enlarged by an installation of a direct PC-pool-facility for student access in our institute.

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The digital slide box - institute-individual computer based training (CDT) in the course of histopathology M. Grunewald*, M. Vieth**, S. Miillel, M. Hofmann", J. G. MiillerO *Department of Radiology, University of Marburg; ** Department of Pathology of the Clinic in Bayreuth; tTIepartment of Pathology, University of Erlangen; "Department of Pathology, University of Liibeck; °Department of Pathology, University of Wiirzburg; Germany

THE USE OF NEURONAL NETWORKS FOR PROGNOSIS PREDICTION IN INVASIVE DUCTAL BREAST CARCINOMAS

Aims: Creation of digital slide boxes as interactive computer pr
F. Theissig, K. Gartner, V. Dimmer. G. Haroske, W. Meyer, K.D. Kunze Institut fur Pathologie der Technischen Universitat Dresden In expert systems it is very difficult to define decision rules for prognosis prediction on the basis of histopathological and chromatin features. This is due to the complexity of the subject. In this study a neuronal Fuzzy system was investigated. At first linguistic termes from experts were given for the variables used for classification. The results were compared with the prognosis. At first the survival time was related to the decision rules of the experts and than with the rules of the neuronal Fuzzy system. The results showed that the system related rules are better than the expert ones. But as a great disadvantage (e.g. in contrast to the linear discriminant analysis) the results cannot be statistically proved if no test sets are available.

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ARTIFICIAL NEURAL NETWORKS: A REVIEW OF BASIC PRINCIPLES AND APPLICATIONS IN PATHOLOGY Torsten Mattfeldt", Hans A. KestlerIDepartment of Pathology and 2Department of Neural Information Processing, University of Ulm Aims: To present a review of basic principles of artificial neural networks (ANNs), illustrated by applications in clinical pathology. Methods: The review is based on an extensive literature retrieval and our own analyses of clinico-pathological data with ANNs. Results: ANNs are highly effective and versatile computational models, originally constructed according to the mode of function of neurons. Due to the improved performance of personal computers in the last years, ANNs have become increasingly popular, which also led to a number of applications in histopathology. In this review, the principles of multilayer feedforward networks with backpropagation (MLFF-BP networks) and of networks based on learning vector quantization (LVQ) are briefly outlined. In most applications in pathology, ANNs are used for the purpose of classification. The nets "Ieam" to predict output data (e.g. postoperative tumour progression) from a set of input data (e.g. tumour stage, tumour grade, immunohistochemical data, ...). This process is known as network training, the cases used for this purpose form the training set. After training the network is confronted with the input variables of new cases (test set). Based on the information from the training set, the network has to predict the output variable in the test set. By comparing these predictions with the true data, the researcher tests the ability of the network to generalize. Different systematic test methods are possible. ANNs are but one example of a variety of methods for classification purposes, such as discriminant analysis. Not infrequently ANNs provide a better accuracy of prediction than classical statistical methods, presumably due to nonlinear effects. Conclusions: As ANNs may provide more accurate predictions than statistical standard methods, their use in multivariate clinico-pathological studies is encouraged, in particular for individual prognosis prediction.

Evaluation of Gradings via inter-categorical kappas Frank Krummenauer--J, Hans-Anton Lehr(2) (1): Department of Medical Statistics and Documentation (2): Department of Pathology, University of Mainz

If new grading rules for diagnosis are proposed to substitute established, but more expensive or invasive diagnostic procedures, their applicability in terms of observer agreement has to be confirmed. Whereas usually lacking reproducibility of diagnoses is refered to the observers, the influence of moderate applicability of the proposed diagnostic score is often ignored. If merely all observers involved in an observer reliability trial cannot distinguish between between two diagnostic categories, one should rather modify the proposed score by combining those categories causing obvious confusion. Therefore we propose a matrix of kappa coefficients, which allows to identify categories causing inacceptable confusion among raters. It is is further illustrated, how an overall rater agreement can be computed in terms of this matrix; furthermore an update formula for the increase in multiple rater agreement is provided, which allows to predict the gain in diagnostic reproducibility by combining undistinguishable categories. The kappa based procedure is illustrated by the application of a three category system based on mitotic figure counts, which was intended to provide a neq quick-classification scheme for 32 mamma tumors. Two cutpoints for the mitotic figure counts were used to derive a three stage diagnostic system. This score, however, shows moderate reproducibility due to confusion of the lower categories, combination of which yields substantial improvement in rater agreement and thus diagnostic reproducibility.