Wyniki wyszukiwania - BazTech

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Improved mammogram interpretation with an ontology-driven editor and mammoviewer - preliminary results

Podsiadły-Marczykowska T., Wróblewska A., Przelaskowski A.

Biocybernetics and Biomedical Engineering

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2008

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Vol. 28, no. 3

51-60

EN

Although mammography is a standard of reference for detection of early breast cancer, as many as 25% of breast cancers may be missed. To reduce the possibility of missing a cancer, the following methods and tools have been proposed: continuing education and training, prospective double reading, retrospective evaluation of missed cases, and use of computer-aided detection (CAD). The purpose of the reported work was to evaluate the usefulness and the potential of our aiding tools: an ontology driven editor for mammographic lesion description (MammoEdit) and a CAD-tool (Mammo Viewer) to enhance radiologist's diagnostic performance. To this end test sample of mammograms was analyzed twice, without and with aiding tools. The obtained data were analyzed using (ROC) analysis and Kappa statistics. Statistical analysis of the test data demonstrated potential of both tools to enhance radiologist's diagnostic performance.

2

Computer-aided interpretation of medical images: mammography case study

Przelaskowski A., Podsiadly-Marczykowska T., Wroblewska A., Boninski P., Bargiel P.

Machine Graphics and Vision

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2007

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Vol. 16, No. 3/4

347-375

EN

This paper presents the current limitations and challenges of computer-aided interpretation of radiological examinations. The analysis and the proposed improvements in interpretation arose from our experience, knowledge and observations with the collected suggestions and conclusions. The emphasized topics are as follows: computer understanding of human determinants of diagnosis, characteristics and enhancement of observer performance, diagnostic accuracy measures of image examinations, computer-aided diagnosis (CAD) systems, and numerical description of medical image-based content. All of these diagnosis support concepts can be integrated into an intelligent diagnosis interface and enhanced, basing on a formal description of semantic image content, i.e. ontology implied as a reliable, dynamic platform of medical knowledge, useful for diagnosis. CAD for mammography and content-based image indexing supported by the ontology were integrated for the needs of an enhanced diagnostic workstation applied in tele-information medical systems. A design of an effective human-machine interface has arisen as the leading problem of the current challenges.

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Enhancement of accuracy in mammograms interpretation using ontology-driven editor for lesions description and CAD tool - preliminary results

Podsiadły-Marczykowska T., Wróblewska A., Przelaskowski A.

Journal of Medical Informatics & Technologies

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2007

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Vol. 11

235--243

EN

Although mammography is the standard of reference for the detection of early breast cancer, as many as 25% of breast cancers may be missed. To reduce the possibility of missing a cancer, the following methods and tools has been proposed: continuing education and training, prospective double reading, retrospective evaluation of missed cases, and use of computer-aided detection (CAD). In the presented paper we report on preliminary results of reducing the number of false-negative cases in mammograms interpretation by using ontology-driven editor for mammograms description, and MammoViewer, a CAD tool for radiologists' perception improvement. The use of editor resulted in reduction of interpretation errors and improved consistency of diagnosis. Computerized image processing methods make the signs of pathologies more conspicuous and so resulted in improvement of lesion perception.

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Irreversible medical image compression: conditions of Acceptability

Przelaskowski A.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2004

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Vol. 8, No 2

303-316

EN

Acceptance of irreversible image compression applicable to medical imagery is controversial in the medical community. The influence of this irreversible process on degradation of diagnostic image features is considered and how to preserve diagnostic accuracy. Fears, doubts, the disadvantages of the data distortion process and the advantages of safe and efficient irreversible compression for image information storage and interchange are discussed. The effects of compression on various image exams are analysed. The conclusion is that irreversible compression is not to be afraid of, but its characteristics should be well understood before implementing it in current practice.

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Subiektywna ocena jakości diagnostycznej kompresowanych stratnie obrazów

Przelaskowski A., Kukuła A., Surowski P.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2003

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Vol. 9, nr 1-2

27-37

PL

Praca zawiera koncepcję subiektywnej oceny wartości diagnostycznej obrazów kompresowanych sprowadzającą się do oceny wyselekcjonowanych cech symptomów patologii oraz innych zmian istotnych w procesie diagnozy mammograficznych badań obrazowych. Zaproponowano prostą (tendencyjnie mało złożoną) procedurę testu, w którym oceniano cztery lokalne cechy diagnostyczne: kontrast, klarowność interpretacji (ostrość), kształt oraz zarysy w skali od 1 (słabe, niewyraźne, ledwo dostrzegalne, zniekształcone) do 3 (wyraźne, dobrze rozróżnianie, regularne, nie budzące wątpliwości). Korzystając z przygotowanego przez dwóch doświadczonych radiologów zestawu 9 mammogramów, zawierających reprezentatywne, trudne diagnostycznie przypadki badań (wybranych spośród ponad 200 obrazów takich przypadków zarejestrowanych w ciągu 3 lat w dwóch ośrodkach radiologicznych) zestawiono 15 grup obrazów testowych zawierających oryginał oraz 4 j ego wersje po kompresji/dekompresji w różnym stopniu metodami falkowymi. Przeprowadzono eksperyment w warunkach klinicznych. Wyniki oceny tych obrazów przez 7 radiologów z 3 ośrodków pozwoliły sformułować wzorzec diagnostyczny, który może być wykorzystany do optymalizacji numerycznych miar jakości i wiarygodności obrazów medycznych, a także do oceny skuteczności systemów wspomagania diagnozy (CAD) oraz w obiektywizacji procesu detekcji patologii.

EN

A method of simplifying the diagnostic accuracy estimation for digitised and lossy compressed mammograms is presented. Subjective ratings of diagnostically important features according to proposed procedure were used for estimation of diagnostic pattern which is a set of mean rates given for each test image. Experts selected the lesion and pathological structure features susceptible to the processing method (i.e. quantization and encoding procedures of used wavelet coders). Moreover, they choose 9 mammograms (from a set of over 200 difficult-to-diagnose cases) containing representative pathology symptoms which are typical for mammography-based diagnosis. Assessment of 15 image test sets by 7 radiologists from 3 medical centres constituted diagnostic pattern which could be used for optimisation of numerical quality measure, in design of Computer Aided Detection and Diagnosis tools and for making the process of pathology detection more objective.