641 research outputs found

    Improvement in Alzheimer's Disease MRI Images Analysis by Convolutional Neural Networks Via Topological Optimization

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    This research underscores the efficacy of Fourier topological optimization in refining MRI imagery, thereby bolstering the classification precision of Alzheimer's Disease through convolutional neural networks. Recognizing that MRI scans are indispensable for neurological assessments, but frequently grapple with issues like blurriness and contrast irregularities, the deployment of Fourier topological optimization offered enhanced delineation of brain structures, ameliorated noise, and superior contrast. The applied techniques prioritized boundary enhancement, contrast and brightness adjustments, and overall image lucidity. Employing CNN architectures VGG16, ResNet50, InceptionV3, and Xception, the post-optimization analysis revealed a marked elevation in performance. Conclusively, the amalgamation of Fourier topological optimization with CNNs delineates a promising trajectory for the nuanced classification of Alzheimer's Disease, portending a transformative impact on its diagnostic paradigms

    Automated detection of Alzheimer disease using MRI images and deep neural networks- A review

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    Early detection of Alzheimer disease is crucial for deploying interventions and slowing the disease progression. A lot of machine learning and deep learning algorithms have been explored in the past decade with the aim of building an automated detection for Alzheimer. Advancements in data augmentation techniques and advanced deep learning architectures have opened up new frontiers in this field, and research is moving at a rapid speed. Hence, the purpose of this survey is to provide an overview of recent research on deep learning models for Alzheimer disease diagnosis. In addition to categorizing the numerous data sources, neural network architectures, and commonly used assessment measures, we also classify implementation and reproducibility. Our objective is to assist interested researchers in keeping up with the newest developments and in reproducing earlier investigations as benchmarks. In addition, we also indicate future research directions for this topic.Comment: 22 Pages, 5 Figures, 7 Table

    Novel Deep Learning Models for Medical Imaging Analysis

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    abstract: Deep learning is a sub-field of machine learning in which models are developed to imitate the workings of the human brain in processing data and creating patterns for decision making. This dissertation is focused on developing deep learning models for medical imaging analysis of different modalities for different tasks including detection, segmentation and classification. Imaging modalities including digital mammography (DM), magnetic resonance imaging (MRI), positron emission tomography (PET) and computed tomography (CT) are studied in the dissertation for various medical applications. The first phase of the research is to develop a novel shallow-deep convolutional neural network (SD-CNN) model for improved breast cancer diagnosis. This model takes one type of medical image as input and synthesizes different modalities for additional feature sources; both original image and synthetic image are used for feature generation. This proposed architecture is validated in the application of breast cancer diagnosis and proved to be outperforming the competing models. Motivated by the success from the first phase, the second phase focuses on improving medical imaging synthesis performance with advanced deep learning architecture. A new architecture named deep residual inception encoder-decoder network (RIED-Net) is proposed. RIED-Net has the advantages of preserving pixel-level information and cross-modality feature transferring. The applicability of RIED-Net is validated in breast cancer diagnosis and Alzheimer’s disease (AD) staging. Recognizing medical imaging research often has multiples inter-related tasks, namely, detection, segmentation and classification, my third phase of the research is to develop a multi-task deep learning model. Specifically, a feature transfer enabled multi-task deep learning model (FT-MTL-Net) is proposed to transfer high-resolution features from segmentation task to low-resolution feature-based classification task. The application of FT-MTL-Net on breast cancer detection, segmentation and classification using DM images is studied. As a continuing effort on exploring the transfer learning in deep models for medical application, the last phase is to develop a deep learning model for both feature transfer and knowledge from pre-training age prediction task to new domain of Mild cognitive impairment (MCI) to AD conversion prediction task. It is validated in the application of predicting MCI patients’ conversion to AD with 3D MRI images.Dissertation/ThesisDoctoral Dissertation Industrial Engineering 201

    Alzheimer’s Disease Diagnosis Using CNN Based Pre-trained Models

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    Memory loss and impairment are signs of Alzheimer's disease (AD), which may also cause other issues. It has a significant impact on patients' lives and is incurable, but rapid recognition of Alzheimer's disease can be useful to initiate appropriate therapy to avoid further deterioration to the brain. Previously, Machine Learning methodswere used to detect Alzheimer's disease. In recent times, Deep Learning algorithms have become more popular for pattern recognition. This workconcentrates on the recognition of Alzheimer's disease at a preliminary phase using advanced convolutional neural network models. As the disease advances, they steadily forget everything. It is critical to detect the disease as quickly as possible. The proposed model usespre-trained models that uses magnetic resonance imaging of the brain to determine if a person has very mild, mild, moderate, or non-dementia. The models used for classification are VGG16, VGG19, and ResNet50 architectures and provide performance comparison

    Classification of Alzheimer’s and Parkinson’s Disease Based on VGG19 Features with Batch Normalization

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    Dementia is a condition when thinking, reasoning and memory skills are lost and patients have emotional instability and personality changes. Researchers are looking into how the underlying disease processes that lead to various kinds of dementia begin and interact. Additionally, they keep researching the various diseases and conditions that cause dementia. Alzheimer’s and Parkinson's disease contribute to dementia development. Recently deep learning-based techniques have surpassed the performance of traditional algorithms in the field of machine vision, image detection, natural language handling, object detection, and medical image analysis. This study proposed a transfer learning-based model for Parkinson’s and Alzheimer’s disease classification from slices of MRI. Pretrained VGG19 with Batch normalization is used for feature extraction and the final dense (fully connected-FC) layers are fine-tuned to meet our requirements. The performance of the model is analyzed by varying hyperparameters. The proposed model outperformed other pre-trained CNN models by achieving an accuracy of 97.19%

    DEEP-AD: The deep learning model for diagnostic classification and prognostic prediction of alzheimer's disease

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    In terms of context, the aim of this dissertation is to aid neuroradiologists in their clinical judgment regarding the early detection of AD by using DL. To that aim, the system design research methodology is suggested in this dissertation for achieving three goals. The first goal is to investigate the DL models that have performed well at identifying patterns associated with AD, as well as the accuracy so far attained, limitations, and gaps. A systematic review of the literature (SLR) revealed a shortage of empirical studies on the early identification of AD through DL. In this regard, thirteen empirical studies were identified and examined. We concluded that three-dimensional (3D) DL models have been generated far less often and that their performance is also inadequate to qualify them for clinical trials. The second goal is to provide the neuroradiologist with the computer-interpretable information they need to analyze neuroimaging biomarkers. Given this context, the next step in this dissertation is to find the optimum DL model to analyze neuroimaging biomarkers. It has been achieved in two steps. In the first step, eight state-of-the-art DL models have been implemented by training from scratch using end-to-end learning (E2EL) for two binary classification tasks (AD vs. CN and AD vs. stable MCI) and compared by utilizing MRI scans from the publicly accessible datasets of neuroimaging biomarkers. Comparative analysis is carried out by utilizing efficiency-effects graphs, comprehensive indicators, and ranking mechanisms. For the training of the AD vs. sMCI task, the EfficientNet-B0 model gets the highest value for the comprehensive indicator and has the fewest parameters. DenseNet264 performed better than the others in terms of evaluation matrices, but since it has the most parameters, it costs more to train. For the AD vs. CN task by DenseNet264, we achieved 100% accuracy for training and 99.56% accuracy for testing. However, the classification accuracy was still only 82.5% for the AD vs. sMCI task. In the second step, fusion of transfer learning (TL) with E2EL is applied to train the EfficientNet-B0 for the AD vs. sMCI task, which achieved 95.29% accuracy for training and 93.10% accuracy for testing. Additionally, we have also implemented EfficientNet-B0 for the multiclass AD vs. CN vs. sMCI classification task with E2EL to be used in ensemble of models and achieved 85.66% training accuracy and 87.38% testing accuracy. To evaluate the model’s robustness, neuroradiologists must validate the implemented model. As a result, the third goal of this dissertation is to create a tool that neuroradiologists may use at their convenience. To achieve this objective, this dissertation proposes a web-based application (DEEP-AD) that has been created by making an ensemble of Efficient-Net B0 and DenseNet 264 (based on the contribution of goal 2). The accuracy of a DEEP-AD prototype has undergone repeated evaluation and improvement. First, we validated 41 subjects of Spanish MRI datasets (acquired from HT Medica, Madrid, Spain), achieving an accuracy of 82.90%, which was later verified by neuroradiologists. The results of these evaluation studies showed the accomplishment of such goals and relevant directions for future research in applied DL for the early detection of AD in clinical settings.En términos de contexto, el objetivo de esta tesis es ayudar a los neurorradiólogos en su juicio clínico sobre la detección precoz de la AD mediante el uso de DL. Para ello, en esta tesis se propone la metodología de investigación de diseño de sistemas para lograr tres objetivos. El segundo objetivo es proporcionar al neurorradiólogo la información interpretable por ordenador que necesita para analizar los biomarcadores de neuroimagen. Dado este contexto, el siguiente paso en esta tesis es encontrar el modelo DL óptimo para analizar biomarcadores de neuroimagen. Esto se ha logrado en dos pasos. En el primer paso, se han implementado ocho modelos DL de última generación mediante entrenamiento desde cero utilizando aprendizaje de extremo a extremo (E2EL) para dos tareas de clasificación binarias (AD vs. CN y AD vs. MCI estable) y se han comparado utilizando escaneos MRI de los conjuntos de datos de biomarcadores de neuroimagen de acceso público. El análisis comparativo se lleva a cabo utilizando gráficos de efecto-eficacia, indicadores exhaustivos y mecanismos de clasificación. Para el entrenamiento de la tarea AD vs. sMCI, el modelo EfficientNet-B0 obtiene el valor más alto para el indicador exhaustivo y tiene el menor número de parámetros. DenseNet264 obtuvo mejores resultados que los demás en términos de matrices de evaluación, pero al ser el que tiene más parámetros, su entrenamiento es más costoso. Para la tarea AD vs. CN de DenseNet264, conseguimos una accuracy del 100% en el entrenamiento y del 99,56% en las pruebas. Sin embargo, la accuracy de la clasificación fue sólo del 82,5% para la tarea AD vs. sMCI. En el segundo paso, se aplica la fusión del aprendizaje por transferencia (TL) con E2EL para entrenar la EfficientNet-B0 para la tarea AD vs. sMCI, que alcanzó una accuracy del 95,29% en el entrenamiento y del 93,10% en las pruebas. Además, también hemos implementado EfficientNet-B0 para la tarea de clasificación multiclase AD vs. CN vs. sMCI con E2EL para su uso en conjuntos de modelos y hemos obtenido una accuracy de entrenamiento del 85,66% y una precisión de prueba del 87,38%. Para evaluar la solidez del modelo, los neurorradiólogos deben validar el modelo implementado. Como resultado, el tercer objetivo de esta disertación es crear una herramienta que los neurorradiólogos puedan utilizar a su conveniencia. Para lograr este objetivo, esta disertación propone una aplicación basada en web (DEEP-AD) que ha sido creada haciendo un ensemble de Efficient-Net B0 y DenseNet 264 (basado en la contribución del objetivo 2). La accuracy del prototipo DEEP-AD ha sido sometida a repetidas evaluaciones y mejoras. En primer lugar, validamos 41 sujetos de conjuntos de datos de MRI españoles (adquiridos de HT Medica, Madrid, España), logrando una accuracy del 82,90%, que posteriormente fue verificada por neurorradiólogos. Los resultados de estos estudios de evaluación mostraron el cumplimiento de dichos objetivos y las direcciones relevantes para futuras investigaciones en DL, aplicada en la detección precoz de la AD en entornos clínicos.Escuela de DoctoradoDoctorado en Tecnologías de la Información y las Telecomunicacione

    A Review on the use of Artificial Intelligence Techniques in Brain MRI Analysis

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    Over the past 20 years, the global research going on in Artificial Intelligence in applica-tions in medication is a venue internationally, for medical trade and creating an ener-getic research community. The Artificial Intelligence in Medicine magazine has posted a massive amount. This paper gives an overview of the history of AI applications in brain MRI analysis to research its effect at the wider studies discipline and perceive de-manding situations for its destiny. Analysis of numerous articles to create a taxono-my of research subject matters and results was done. The article is classed which might be posted between 2000 and 2018 with this taxonomy. Analyzed articles have excessive citations. Efforts are useful in figuring out popular studies works in AI primarily based on mind MRI analysis throughout specific issues. The biomedical prognosis was ruled by way of knowledge engineering research in its first decade, whilst gadget mastering, and records mining prevailed thereafter. Together these two topics have contributed a lot to the latest medical domain

    ADNet : diagnóstico assistido por computador para doença de Alzheimer usando rede neural convolucional 3D com cérebro inteiro

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    Orientadores: Anderson de Rezende Rocha, Marina WeilerDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: Demência por doença de Alzheimer (DA) é uma síndrome clínica caracterizada por múltiplos problemas cognitivos, incluindo dificuldades na memória, funções executivas, linguagem e habilidades visuoespaciais. Sendo a forma mais comum de demência, essa doença mata mais do que câncer de mama e de próstata combinados, além de ser a sexta principal causa de morte nos Estados Unidos. A neuroimagem é uma das áreas de pesquisa mais promissoras para a detecção de biomarcadores estruturais da DA, onde uma técnica não invasiva é usada para capturar uma imagem digital do cérebro, a partir da qual especialistas extraem padrões e características da doença. Nesse contexto, os sistemas de diagnóstico assistido por computador (DAC) são abordagens que visam ajudar médicos e especialistas na interpretação de dados médicos, para fornecer diagnósticos aos pacientes. Em particular, redes neurais convolucionais (RNCs) são um tipo especial de rede neural artificial (RNA), que foram inspiradas em como o sistema visual funciona e, nesse sentido, têm sido cada vez mais utilizadas em tarefas de visão computacional, alcançando resultados impressionantes. Em nossa pesquisa, um dos principais objetivos foi utilizar o que há de mais avançado sobre aprendizagem profunda (por exemplo, RNC) para resolver o difícil problema de identificar biomarcadores estruturais da DA em imagem por ressonância magnética (IRM), considerando três grupos diferentes, ou seja, cognitivamente normal (CN), comprometimento cognitivo leve (CCL) e DA. Adaptamos redes convolucionais com dados fornecidos principalmente pela ADNI e avaliamos no desafio CADDementia, resultando em um cenário mais próximo das condições no mundo real, em que um sistema DAC é usado em um conjunto de dados diferente daquele usado no treinamento. Os principais desafios e contribuições da nossa pesquisa incluem a criação de um sistema de aprendizagem profunda que seja totalmente automático e comparativamente rápido, ao mesmo tempo em que apresenta resultados competitivos, sem usar qualquer conhecimento específico de domínio. Nomeamos nossa melhor arquitetura ADNet (Alzheimer's Disease Network) e nosso melhor método ADNet-DA (ADNet com adaptação de domínio), o qual superou a maioria das submissões no CADDementia, todas utilizando conhecimento prévio da doença, como regiões de interesse específicas do cérebro. A principal razão para não usar qualquer informação da doença em nosso sistema é fazer com que ele aprenda e extraia padrões relevantes de regiões importantes do cérebro automaticamente, que podem ser usados para apoiar os padrões atuais de diagnóstico e podem inclusive auxiliar em novas descobertas para diferentes ou novas doenças. Após explorar uma série de técnicas de visualização para interpretação de modelos, associada à inteligência artificial explicável (XAI), acreditamos que nosso método possa realmente ser empregado na prática médica. Ao diagnosticar pacientes, é possível que especialistas usem a ADNet para gerar uma diversidade de visualizações explicativas para uma determinada imagem, conforme ilustrado em nossa pesquisa, enquanto a ADNet-DA pode ajudar com o diagnóstico. Desta forma, os especialistas podem chegar a uma decisão mais informada e em menos tempoAbstract: Dementia by Alzheimer's disease (AD) is a clinical syndrome characterized by multiple cognitive problems, including difficulties in memory, executive functions, language and visuospatial skills. Being the most common form of dementia, this disease kills more than breast cancer and prostate cancer combined, and it is the sixth leading cause of death in the United States. Neuroimaging is one of the most promising areas of research for early detection of AD structural biomarkers, where a non-invasive technique is used to capture a digital image of the brain, from which specialists extract patterns and features of the disease. In this context, computer-aided diagnosis (CAD) systems are approaches that aim at assisting doctors and specialists in interpretation of medical data to provide diagnoses for patients. In particular, convolutional neural networks (CNNs) are a special kind of artificial neural network (ANN), which were inspired by how the visual system works, and, in this sense, have been increasingly used in computer vision tasks, achieving impressive results. In our research, one of the main goals was bringing to bear what is most advanced in deep learning research (e.g., CNN) to solve the difficult problem of identifying AD structural biomarkers in magnetic resonance imaging (MRI), considering three different groups, namely, cognitively normal (CN), mild cognitive impairment (MCI), and AD. We tailored convolutional networks with data primarily provided by ADNI, and evaluated them on the CADDementia challenge, thus resulting in a scenario very close to the real-world conditions, in which a CAD system is used on a dataset differently from the one used for training. The main challenges and contributions of our research include devising a deep learning system that is both completely automatic and comparatively fast, while also presenting competitive results, without using any domain specific knowledge. We named our best architecture ADNet (Alzheimer's Disease Network), and our best method ADNet-DA (ADNet with domain adaption), which outperformed most of the CADDementia submissions, all of them using prior knowledge from the disease, such as specific regions of interest of the brain. The main reason for not using any information from the disease in our system is to make it automatically learn and extract relevant patterns from important regions of the brain, which can be used to support current diagnosis standards, and may even assist in new discoveries for different or new diseases. After exploring a number of visualization techniques for model interpretability, associated with explainable artificial intelligence (XAI), we believe that our method can be actually employed in medical practice. While diagnosing patients, it is possible for specialists to use ADNet to generate a diversity of explanatory visualizations for a given image, as illustrated in our research, while ADNet-DA can assist with the diagnosis. This way, specialists can come up with a more informed decision and in less timeMestradoCiência da ComputaçãoMestre em Ciência da Computaçã

    Functional Organization of the Brain at Rest and During Complex Tasks Using fMRI

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    How and why functional connectivity (FC), which captures the correlations among brain regions and/or networks, differs in various brain states has been incompletely understood. I review high-level background on this problem and how it relates to 1) the contributions of task-evoked activity, 2) white-matter fMRI, and 3) disease states in Chapter 1. In Chapter 2, based on the notion that brain activity during a task reflects an unknown mixture of spontaneous activity and task-evoked responses, we uncovered that the difference in FC between a task state (a naturalistic movie) and resting state only marginally (3-15%) reflects task-evoked connectivity. Instead, these changes may reflect changes in spontaneously emerging networks. In Chapter 3, we were able to show subtle task-related differences in the white matter using fMRI, which has only rarely been used to study functions in this tissue type. In doing so, we also demonstrated that white matter independent components were also hierarchically organized into axonal fiber bundles, challenging the conventional practice of taking white-matter signals as noise or artifacts. Finally, in Chapter 4, we examined the utility of combining FC with task-activation studies in uncovering changes in brain activity during preclinical Alzheimer\u27s Disease (mild cognitive impairment (MCI) and subjective cognitive decline (SCD) populations), based on data collected at the Indiana University School of Medicine. We found a reduction in neural task-based activations and resting-state FC that appeared to be directly related to diagnostic severity. Taken together, the work presented in this dissertation paves the way for a novel framework for understanding neural dynamics in health and disease
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