45 research outputs found

    Assessment of significance of features acquired from thyroid ultrasonograms in Hashimoto’s disease

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    Introduction: This paper concerns the analysis of the features obtained from thyroid ultrasound images in left and right transverse and longitudinal sections. In the image analysis, the thyroid lobe is treated as a texture for healthy subjects and patients with Hashimoto's disease. The applied methods of analysis and image processing were profiled to obtain 10 features of the image. Then, their significance in the classification was shown.Material: In this study, the examined group consisted of 29 healthy subjects aged 18 to 60 and 65 patients with Hashimoto's disease. For each subject, four ultrasound images were taken. They were all in transverse and longitudinal sections of the right and left lobe of the thyroid, which gave 376 images in total.Method: 10 different features obtained from each ultrasound image were suggested. The analyzed thyroid lobe was marked automatically or manually with a rectangular element.Results: The analysis of 10 features and the creation for each one of them their own decision tree configuration resulted in distinguishing 3 most significant features. The results of the quality of classification show accuracy above 94% for a non-trimmed decision tree

    Influence of the measurement method of features in ultrasound images of the thyroid in the diagnosis of Hashimoto's disease

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    Introduction: This paper shows the influence of a measurement method of features in the diagnosis of Hashimoto's disease. Sensitivity of the algorithm to changes in the parameters of the ROI, namely shift, resizing and rotation, has been presented. The obtained results were also compared to the methods known from the literature in which decision trees or average gray level thresholding are used.Material: In the study, 288 images obtained from patients with Hashimoto's disease and 236 images from healthy subjects have been analyzed. For each person, an ultrasound examination of the left and right thyroid lobe in transverse and longitudinal sections has been performed.Method: With the use of the developed algorithm, a discriminant analysis has been conducted for the following five options: linear, diaglinear, quadratic, diagquadratic and mahalanobis. The left and right thyroid lobes have been analyzed both together and separately in transverse and longitudinal sections. In addition, the algorithm enabled to analyze specificity and sensitivity as well as the impact of sensitivity of ROI shift, repositioning and rotation on the measured features.Results and summary: The analysis has shown that the highest accuracy was obtained for the longitudinal section (LD) with the method of linear, yielding sensitivity = 76%, specificity = 95% and accuracy ACC = 84%. The conducted sensitivity assessment confirms that changes in the position and size of the ROI have little effect on sensitivity and specificity. The analysis of all cases, that is, images of the left and right thyroid lobes in transverse and longitudinal sections, has shown specificity ranging from 60% to 95% and sensitivity from 62% to 89%. Additionally, it was shown that the value of ACC for the method using decision trees as a classifier is equal to 84% for the analyzed data. Thresholding of average brightness of the ROI gave ACC equal to 76%

    Mobile sailing robot for automatic estimation of fish density and monitoring water quality

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    Introduction: The paper presents the methodology and the algorithm developed to analyze sonar images focused on fish detection in small water bodies and measurement of their parameters: volume, depth and the GPS location. The final results are stored in a table and can be exported to any numerical environment for further analysis.Material and method: The measurement method for estimating the number of fish using the automatic robot is based on a sequential calculation of the number of occurrences of fish on the set trajectory. The data analysis from the sonar concerned automatic recognition of fish using the methods of image analysis and processing.Results: Image analysis algorithm, a mobile robot together with its control in the 2.4 GHz band and full cryptographic communication with the data archiving station was developed as part of this study. For the three model fish ponds where verification of fish catches was carried out (548, 171 and 226 individuals), the measurement error for the described method was not exceeded 8%.Summary: Created robot together with the developed software has features for remote work also in the variety of harsh weather and environmental conditions, is fully automated and can be remotely controlled using Internet. Designed system enables fish spatial location (GPS coordinates and the depth). The purpose of the robot is a non-invasive measurement of the number of fish in water reservoirs and a measurement of the quality of drinking water consumed by humans, especially in situations where local sources of pollution could have a significant impact on the quality of water collected for water treatment for people and when getting to these places is difficult. The systematically used robot equipped with the appropriate sensors, can be part of early warning system against the pollution of water used by humans (drinking water, natural swimming pools) which can be dangerous for their health

    PORÓWNANIE WPŁYWU STANDARYZACJI I NORMALIZACJI DANYCH NA SKUTECZNOŚĆ KLASYFIKACJI TEKSTURY TKANKI GĄBCZASTEJ KRĘGOSŁUPA

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    The aim of this article was to compare the influence of the data pre-processing methods – normalization and standardization – on the results of the classification of spongy tissue images. Four hundred CT images of the spine (L1 vertebra) were used for the analysis. The images were obtained from fifty healthy patients and fifty patients with diagnosed with osteoporosis. The samples of tissue (50×50 pixels) were subjected to a texture analysis to obtain descriptors of features based on a histogram of grey levels, gradient, run length matrix, co-occurrence matrix, autoregressive model and wavelet transform. The obtained results were set in the importance ranking (from the most important to the least important), and the first fifty features were used for further experiments. These data were normalized and standardized and then classified using five different methods: naive Bayes classifier, support vector machine, multilayer perceptrons, random forest and classification via regression. The best results were obtained for standardized data and classified by using multilayer perceptrons. This algorithm allowed for obtaining high accuracy of classification at the level of 94.25%.Celem niniejszego artykułu było porównanie wpływu metod wstępnego przetwarzania danych - normalizacji i standaryzacji - na wyniki klasyfikacji obrazów tkanki gąbczastej. Do analiz wykorzystano czterysta obrazów tomografii komputerowej kręgosłupa (kręg L1). Obrazy pochodziły od pięćdzisięciu zdrowych pacjentów oraz pięćdziesięciu pacjentów ze zdiagnozowaną osteoporozą. Uzyskane próbki tkanki (50×50 pikseli) poddano analizie tekstury w wyniku czego otrzymano deskryptory cech oparte na histogramie poziomów szarości, macierzy gradientu, macierzy RL, macierzy zdarzeń, modelu autoregresji i transformacie falkowej. Otrzymane wyniki ustawiono w rankingu ważności (od najistotniejszej do najmniej ważnej), a pięćdziesiąt pierwszych cech wykorzystano do dalszych eksperymentów. Dane zostały poddane normalizacji oraz standaryzacji, a następnie klasyfikowane przy użyciu pięciu różnych metod: naiwny klasyfikator Bayesa, maszyna wektorów wspierających, wielowarstwowe perceptrony, las losowy oraz klasyfikacji poprzez regresje. Najlepsze wyniki uzyskano dla danych na których przeprowadzono standaryzacje i poddano klasyfikacji za pomocą wielowarstwowych perceptronów. Taki algorytm postępowania pozwolił na uzyskanie wysokiej skuteczności klasyfikacji na poziomie 94,25%

    ZASTOSOWANIE METODY HELLWIGA DO REDUKCJI WYMIARU PRZESTRZENI CECH OBRAZÓW USG TARCZYCY

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    This paper presents the use of Hellwig’s method for dimension reduction in feature space of thyroid ultrasound images. On the base of this method, the combination of three features with the greatest value of Hellwig’s index information capacity from the input set of 283 features was obtained. This set was used to build and test the classifiers. Classification results were compared with the results obtained for a set of 48 features obtained using correlation method. It turned out that the accuracy of classifiers built on the base of 3 features is not worse than the accuracy of classifiers built on the base of 48 features, and in some cases it is even higher. This suggests that the Hellwig’s method can be used as an effective method for dimension reduction in feature space for the future thyroid ultrasound images classification.W artykule przedstawiono wyniki zastosowania metody Hellwiga do redukcji wymiaru przestrzeni cech obrazów USG tarczycy. Za pomocą tej metody, z wejściowego zbioru 283 cech otrzymano kombinację 3 cech z największą wartością wskaźnika pojemności informacyjnej Hellwiga. Zbiór ten posłużył do budowy i testowania klasyfikatorów. Wyniki klasyfikacji porównano z wynikami uzyskanymi dla 48 cech otrzymanych za pomocą metody korelacji. Okazało się, że dokładność klasyfikatorów zbudowanych ze zbioru liczącego 3 cechy nie jest gorsza od dokładności klasyfikatorów dla 48 cech, a w kilku przypadkach nawet ją przewyższa. Sugeruje to, że metoda Hellwiga może być wykorzystana jako wydajna metoda redukcji wymiaru przestrzeni cech dla potrzeb przyszłej klasyfikacji obrazów USG tarczycy

    Machine learning, medical diagnosis, and biomedical engineering research - commentary

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    A large number of papers are appearing in the biomedical engineering literature that describe the use of machine learning techniques to develop classifiers for detection or diagnosis of disease. However, the usefulness of this approach in developing clinically validated diagnostic techniques so far has been limited and the methods are prone to overfitting and other problems which may not be immediately apparent to the investigators. This commentary is intended to help sensitize investigators as well as readers and reviewers of papers to some potential pitfalls in the development of classifiers, and suggests steps that researchers can take to help avoid these problems. Building classifiers should be viewed not simply as an add-on statistical analysis, but as part and parcel of the experimental process. Validation of classifiers for diagnostic applications should be considered as part of a much larger process of establishing the clinical validity of the diagnostic technique

    DIAGNOSTYKA RÓŻNICOWA ASEPTYCZNEGO I SEPTYCZNEGO OBLUZOWANIA PANEWKI ENDOPROTEZY STAWU BIODROWEGO METODAMI TOMOGRAFII POLARYZACYJNEJ

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    Manuscript contains structural-logical scheme and analytical description of the differential diagnosis of aseptic and septic loosening of the artificial hip joint endoprosthesis using the methods of differential Mueller-matrix mapping of circular birefringence (CB) distributions of polycrystalline synovial films (SF) and results of determining the sensitivity, specificity and accuracy of the wavelet analysis method of differential Mueller-matrix mapping of the distributions of the CB values of polycrystalline films SF patients from the control group and groups with different severity of the hip joint pathology.Manuskrypt zawiera schemat strukturalno-logiczny i opis analityczny diagnostyki różnicowej aseptycznego i septycznego obluzowania sztucznej endoprotezy stawu biodrowego z wykorzystaniem metod różnicowego mapowania macierzy Muellera rozkładów dwójłomności kołowej polikrystalicznych filmów błony maziowej i wyników określania czułości, swoistości i dokładności metody analizy falkowej różnicowego mapowania macierzy Muellera rozkładów wartości dwójłomności kołowej polikrystalicznych filmów SF pacjentów z grupy kontrolnej i grup o różnym nasileniu patologii stawu biodrowego

    Automatic analysis of 2D polyacrylamide gels in the diagnosis of DNA polymorphisms

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    Introduction: The analysis of polyacrylamide gels is currently carried out manually or automatically. In the automatic method, there are limitations related to the acceptable degree of distortion of lane and band continuity. The available software cannot deal satisfactorily with this type of situations. Therefore, the paper presents an original image analysis method devoid of the aforementioned drawbacks.Material: This paper examines polyacrylamide gel images from Li-Cor DNA Sequencer 4300S resulting from the use of the electrophoretic separation of DNA fragments. The acquired images have a resolution dependent on the length of the analysed DNA fragments and typically it is MG×NG=3806×1027 pixels. The images are saved in TIFF format with a grayscale resolution of 16 bits/pixel. The presented image analysis method was performed on gel images resulting from the analysis of DNA methylome profiling in plants exposed to drought stress, carried out with the MSAP (Methylation Sensitive Amplification Polymorphism) technique.Results: The results of DNA polymorphism analysis were obtained in less than one second for the Intel Core™ 2 Quad CPU [email protected], 8GB RAM. In comparison with other known methods, specificity was 0.95, sensitivity = 0.94 and AUC (Area Under Curve) = 0.98.Conclusions: It is possible to carry out this method of DNA polymorphism analysis on distorted images of polyacrylamide gels. The method is fully automatic and does not require any operator intervention. Compared with other methods, it produces the best results and the resulting image is easy to interpret. The presented method of measurement is used in the practical analysis of polyacrylamide gels in the Department of Genetics at the University of Silesia in Katowice, Poland

    Clinical health psychology in practice : theory and case presentations

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    Thyroid nodule core needle biopsy — current approach

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    Fine needle aspiration biopsy (FNAB) guided by ultrasonography is routinely used to identify thyroid nodules prior to surgery. Although FNAB has great diagnostic accuracy and safety, it is limited by its relatively low diagnostic accuracy in follicular lesions, such as non-diagnostic or atypia of unclear significance (AUS)/follicular lesion of uncertain significance (FLUS). Additional diagnostic tests are required to overcome these challenges in evaluating thyroid nodules. Thyroid nodules can now be diagnosed with spring-activated single- or double-action needles following the introduction of core needle biopsy (CNB). CNB has the ability to address the limitations of FNAB by obtaining a sizeable tissue sample with more details on the histological structure supporting the capsule and fewer non-diagnostic effects brought on by the absence of follicular cells. Compared to repeated FNAB, CNB has been demonstrated to produce fewer ambiguous results, such as non-diagnostic or AUS/FLUS results. The Korean Endocrine Pathology Thyroid CNB Working Group issued its first set of guidelines for “Pathology Reporting of Thyroid Core Needle Biopsy” in 2015. In 2017, the Korean Society of Thyroid Radiology (KSThR) published “Core Needle Biopsy of Thyroid: 2016 Consensus Statement and Recommendations from the Korean Society of Thyroid Radiology”. The main objectives of thyroid CNB are to detect individuals with thyroid illness who require surgery and to obtain a significant number of thyroid lesions with low morbidity
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