Computerunterstützte Diagnoseverfahren

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1 Computerunterstützte Diagnoseverfahren Klaus-Peter Adlassnig Section on Medical Expert and Knowledge-Based Systems Core Unit for Medical Statistics and Informatics Medical University of Vienna International Journal Artificial Intelligence in Medicine Editor-in-Chief

2 Computers in Clinical Medicine step 1: patient administration admission, transfer, discharge, and cost billing step 2: documentation of patients medical data electronic health record: life-long, multimedia step 3: patient data retrieval medical research databases quality assurance in the medical institution step 4: software-based clinical decision support quality assurance for the particular patient

3 Clinical Decision Support quality assurance of clinical decision making: for the particular patient determination of correct diagnoses data interpretation and monitoring single or differential diagnosis * further diagnostic investigations * all pathological signs are accounted for selection of optimal therapies treatment recommendations contraindication alerts drug interaction warnings assessment of prognosis development of illness optimal management for the patient clinical reminders medical protocols, guidelines, and pathways

4 patient s medical data physician s medical knowledge symptoms signs test results clinical findings biosignals images diagnoses therapies nursing data standardization telecommunication chip cards information systems single patient many patients induction deduction general knowledge general knowledge diagnosis therapy prognosis management anatomy biochemistry physiology pathophysiology pathology nosology therapeutic knowledge disease management subjective experience intuition knowledge-based systems telemedicine integration telemedicine

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6 Der sog.»schmerzlose Ikterus«ist keineswegs typisch für die Pankreaskopftumoren (weniger als 20%). Vielmehr sind die häufigsten Frühsymptome Schmerzen mit unbestimmten Verdauungsstörungen und Gewichtsverlust. Unter den Tumormarkern hat das Ca 19-9 eine relative Semispezifität für das Pankreaskarzinom. Es eignet sich zur Differenzierung von chronischer Pankreatitis und Karzinom...

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8 differential diagnosis

9 from: J.A.Pinard et al. (2003) Maternal Serologic Screening for Toxoplasmosis. Journal of Midwifery & Women s Health 48,

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20 Structure of Knowledge-Based Systems in Medicine expert system information system medical problem solving methods medical knowledge bases patient s medical data rule-based recommendations differential diagnosis laboratory test interpretation ICU monitoring device control rules with recommendations disease profiles interpretive reports pathophysiological state models device control rules patient data symptoms, signs, test results laboratory test results patient data patient and device data

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22 Knowledge-Based Methodology in Medicine knowledge modeling of knowledge * diagnostic knowledge, therapy recommendations, prognostic information, best medical-practice management guidelines modeling based on linguistic concepts * recounted patient history, perception of characteristic signs, interpreted laboratory measurements, concepts of pathophysiological states, diagnostic, therapeutic, and prognostic concepts objective and subjective medical knowledge * definitional, causal, statistical, and heuristic knowledge health knowledge * medical standards, work plans, legal requirements, etc. data data-to-symbol conversion *1 st step to intelligence recounted, perceived, observed, and measured medical data * patient history, physical examinations, laboratory tests, and clinical investigations

23 Medical Knowledge knowledge representation and processing decision tables, trees, and graphs decision rules and frames n-ary relationships between medical entities standardization, e.g., ARDEN syntax (and FuzzyARDEN) j.md MedFrame guideline languages, e.g., ARDEN Syntax, PROforma, GLIF general basis ICD International Classification of Diseases SNOMED Systematized Nomenclature of Medicine LOINC Logical Observation Identifiers Names and Codes UMLS Unified Medical Language System FMA Foundational Model of Anatomy

24 Towards a Clinical Science measuring everything measurable and trying to make measurable that which has not been measurable so far Galileo Galilei patient s medical data and healthcare processes for human processing patient s medical data and healthcare processes for machine processing

25 Knowledge-Based Patient Care paper chart, partially electronic physician expert system medical knowledge base patient record fully electronic, integrated system health care personnel medical decision support logic electronic health care record

26 Numeric and Symbolic Levels in Knowledge-Based Systems

27 Uncertainty in Medicine imprecision (=fuzziness) of medical concepts due to the unsharpness of boundaries of linguistic concepts; gradual transition from one concept to another modelled by fuzzy sets uncertainty of medical conclusions due to the uncertainty of the occurrence and co-occurrence of imprecise medical concepts modelled by SigmaCounts (unconditioned and conditioned frequencies of fuzzy sets) incompleteness of medical data and medical theory due to only partially known data and partially known explanations for medical phenomena modelled by fuzzy intervalls

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30 Medical problem solving is the process of making adequate decisions with inadequate information. Anonymous

31 Genese medizinischer Expertensysteme Medizinische Expertensysteme Medizinische Künstliche Intelligenz Medizinische Informatik Medizin (Kliniker) KI (Informatiker) Diagnose Therapie Prognose Patientenmanagement Informatik Philosophie Psychologie Linguistik

32 A Sampling of Intelligences I from: Gardner, H. (1998) A Multiplicity of Intelligences. Scientific American Presents Vol. 9, No. 4,

33 A Sampling of Intelligences II from: Gardner, H. (1998) A Multiplicity of Intelligences. Scientific American Presents Vol. 9, No. 4,

34 Artificial Intelligence (1) Definition 1: AI is a field of science and engineering concerned with the computational understanding of what is commonly called intelligent behavior, and with the creation of artifacts that exhibit such behavior. from: Shapiro SC. Artificial intelligence. In: Shapiro SC, editor. Encyclopedia of Artificial Intelligence. 2nd ed., vol. 1. New York: Wiley, 1992, pp Definition 2: AI is the science of artificial simulation of human thought processes with computers. from: Feigenbaum EA, Feldman J. editors. Computers & Thought. Menlo Park: AAAI Press 1995, back cover.

35 Artificial Intelligence (2) It is the decomposition of entire thought processes and their separate artificial simulation also of simple instances of thought that make the task of AI manageable. A functionality-driven science of AI that extends humans through computer systems step by step can immediately be established. artificial-intelligence-augmented systems from: Adlassnig KP. Artificial-intelligence-augmented systems. Artificial Intelligence in Medicine 24, 2002, pp. 1 4.

36 Medizinische Dokumentation Biomedizinische Technik Wissensbasierte Methoden in der Biomechanik, Robotertechnik Wissensbasierte Überprüfung auf Datenvollständigkeit und -konsistenz, wissensbasierte Dokumentationsund Informationssysteme Laboratoriumsmedizin Wissensbasierte Alarmmodule, wissensbasierte Interpretationsprogramme Wissensbasiertes Studiendesign Medizinische Statistik und Biometrie Medizinische Expertenund wissensbasierte Systeme Wissensbasierte Analyse und Design von Biomolekülen, wissensbasierte Suchverfahren in molekularbiologischen Datenbanken Wissensbasierte adaptive Befundungs- und Betrachtungsstationen, digitale anatomische Atlanten, wissensbasierte Bildverarbeitung Wissensbasierte Konsultationssysteme für Diagnose und Therapie, wissensbasierte Monitoringsysteme zur diagnostischen Früherkennung und Therapieüberwachung Klinische Medizin und Intensivmedizin Bioinformatik Bildgebende Medizin

37 Ein selbstbalancierender, 28gelenkiger adaptiver Zweibeiner; eine elektrochemische Reduktionsfabrik samt gesonderter Stauräume für spezielle Energieextrakte in Speicherbatterien, mit denen dann Tausende hydraulischer und pneumatischer Pumpen mit anhängenden Motoren betrieben werden; Kilometer Kapillaren;... gesteuert wird dieser ganze außerordentlich komplexe Mechanismus mit hervorragender Präzision von einem Gefechtsturm aus; darin befinden sich teleskopische und mikroskopische Entfernungsmesser, die selbsttätig registrieren und protokollieren, ferner ein Spektroskop und anderes mehr; das Kommando im Gefechtsturm steht in enger Verbindung mit der klimatisierten Luftaufnahme und der Hauptzufuhr für Brennstoff... R. Buckminster Fuller, A Definition of a Man in Raymond Kurzweil, Das Zeitalter der Künstlichen Intelligenz, 1993 Carl Hanser Verlag, München Wien

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39 1. knowledge representation formalization and representation of medical knowledge in a knowledge base 2. knowledge acquisition knowledge transfer from the expert to the computer (possible contribution to standardization; filling of white patches ) 3. inference method connection between single data of a patient with stored medical knowledge 4. evaluation of correctness and applicability 5. man/machine interface and network integration 6. legal aspects Project Phases

40 Knowledge Representation formalization and representation of medical knowledge in a knowledge base questions: degree of structuralization (degree of theory formation in the domain) type of knowledge (definitional, causal, statistical, heuristic) imprecision, uncertainty, and incompleteness formal models: logical models (two- and many-valued) rules (with and without uncertainty) objects (direct representation of complex structures) networks (associative or causal)