126 research outputs found

    An Automatic Level Set Based Liver Segmentation from MRI Data Sets

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    A fast and accurate liver segmentation method is a challenging work in medical image analysis area. Liver segmentation is an important process for computer-assisted diagnosis, pre-evaluation of liver transplantation and therapy planning of liver tumors. There are several advantages of magnetic resonance imaging such as free form ionizing radiation and good contrast visualization of soft tissue. Also, innovations in recent technology and image acquisition techniques have made magnetic resonance imaging a major tool in modern medicine. However, the use of magnetic resonance images for liver segmentation has been slow when we compare applications with the central nervous systems and musculoskeletal. The reasons are irregular shape, size and position of the liver, contrast agent effects and similarities of the gray values of neighbor organs. Therefore, in this study, we present a fully automatic liver segmentation method by using an approximation of the level set based contour evolution from T2 weighted magnetic resonance data sets. The method avoids solving partial differential equations and applies only integer operations with a two-cycle segmentation algorithm. The efficiency of the proposed approach is achieved by applying the algorithm to all slices with a constant number of iteration and performing the contour evolution without any user defined initial contour. The obtained results are evaluated with four different similarity measures and they show that the automatic segmentation approach gives successful results

    SIEĆ NEURONOWA I ALGORYTM KONWOLUCYJNY DO WYODRĘBNIANIA KSZTAŁTÓW W SYSTEMIE E-MEDICUS

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    The solution shows the architecture of the system collecting and analyzing data. There was tried to develop algorithms to image segmentation. These algorithms are needed to identify arbitrary number of phases for the segmentation problem. With the use of algorithms such as the level set method, neural networks and deep learning methods, it can obtain a quicker diagnosis and automatically marking areas of the interest region in medical images.Rozwiązanie pokazuje architekturę systemu zbierającego i analizującego dane. Opracowano algorytmy segmentacji obrazu. Algorytmy te są potrzebne do identyfikacji dowolnej liczby faz dla problemu segmentacji. Dzięki zastosowaniu algorytmów, takich jak metoda zbiorów poziomicowych, sieci neuronowych i metody głębokiego uczenia się, można uzyskać szybszą diagnozę i automatyczne oznaczanie obszarów w regionie zainteresowania w obrazach medycznych

    ANALIZA OBRAZÓW MEDYCZNYCH I STEREOSKOPOWYCH W SYSTEMIE E-MEDICUS

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    In this work, there were implemented methods to analyze and segmentation medical images by using different kind of algorithms. The solution shows the architecture of the system collecting and analyzing data. There was tried to develop an algorithm for level set method applied to piecewise constant image segmentation. These algorithms are needed to identify arbitrary number of phases for the segmentation problem. With the use of modern algorithms, it can obtain a quicker diagnosis and automatically marking areas of the interest region in medical images.W pracy zaimplementowano metody analizy i segmentacji obrazów medycznych przy użyciu różnych algorytmów. Rozwiązanie pokazuje architekturę systemu zbierającego i analizującego dane. Podjęto próbę opracowania algorytmu dla metody zbiorów poziomicowych stosowanej do fragmentarycznej, stałej segmentacji obrazu. Metody te są potrzebne do identyfikacji dowolnej liczby faz dla problemu segmentacji. Dzięki zastosowaniu nowoczesnych algorytmów można uzyskać szybszą diagnozę i automatyczne oznaczanie obszarów w regionach zainteresowania w obrazach medycznych

    Level set medical image segmentation aided by cooperative quantum particle optimization with Lévy flights

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    Image segmentation plays an important part of image processing, and is also the premise and basis of image analysis and image understanding and recognition. Among the level set based methods, the original Local Binary Fitting (LBF) algorithm is a successful deterministic algorithm that suffers from sensitization to size of the local minimum, image contours, shapes, and initial positions. Among them, Level Set method promotes the two-dimensional problem to the three-dimensional one and then solves it using implicit method to express closed curve of plane. In this article, a novel Level Set model aided by PSO was proposed to solve automated medical image segmentation. The experimental result of segmentations on the benchmark shows that our proposed method is effective to both simple and complex medical images

    How to collect high quality segmentations: use human or computer drawn object boundaries?

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    High quality segmentations must be captured consistently for applications such as biomedical image analysis. While human drawn segmentations are often collected because they provide a consistent level of quality, computer drawn segmentations can be collected efficiently and inexpensively. In this paper, we examine how to leverage available human and computer resources to consistently create high quality segmentations. We propose a quality control methodology. We demonstrate how to apply this approach using crowdsourced and domain expert votes for the "best" segmentation from a collection of human and computer drawn segmentations for 70 objects from a public dataset and 274 objects from biomedical images. We publicly share the library of biomedical images which includes 1,879 manual annotations of the boundaries of 274 objects. We found for the 344 objects that no single segmentation source was preferred and that human annotations are not always preferred over computer annotations. These results motivated us to examine the traditional approach to evaluate segmentation algorithms, which involves comparing the segmentations produced by the algorithms to manual annotations on benchmark datasets. We found that algorithm benchmarking results change when the comparison is made to consensus-voted segmentations. Our results led us to suggest a new segmentation approach that uses machine learning to predict the optimal segmentation source and a modified segmentation evaluation approach.National Science Foundation (IIS-0910908
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