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Showing 2 results for Convolutional Neural Network
Hippocampal Atrophy Studying in Alzheimer's Disease Diagnosis Using Brain MRI Images
Mona Sarhadi, Mohammad Amin Shayegan,
Volume 15, Issue 1 (3-2021)
Abstract
Background and Aim: For effective treatment of Alzheimer's disease (AD), it is important to accurately diagnosis of AD and its earlier stage, Mild Cognitive Impairment (MCI). One of the most important approaches of early detection of AD is to measure atrophy, which uses various kinds of brain scans, such as MRI. The main objective of the current research was to provide a computerized diagnostic system for early diagnosis of AD, using leraning machine algorithms, to help physicians. The proposed system diagnoses AD by examining the hippocampal atrophy of brain MRI images and increases the accuracy of the diagnosis.
Materials and Methods: In this study, hippocampus was segmented from the other parts of the brain by using active contour and convolutional neural network and then, three groups of “Normal Controls: NC”, AD and MCI were classified by using the SVM classifier.
Results: The proposed method has succeeded in classifying AD against NC with 98.77%, 98.74% and 97.96% in average for accuracy, sensitivity and specificity, respectively. Also in classification of MCI against NC, the mean accuracy, sensitivity and specificity of 96.14%, 96.23% and 88.21% were achieved, respectively. Compared with the nearest rival method, the proposed method showed improvement accuracy and sensitivity of classification AD from NC with 1.64% and 2.81% respectively. Also, in classification of MCI from NC it showed improvement for accuracy with 8.9% and sensitivity with 2.16%, respectively. Improving in results were due to the use of a modified ACM segmentation algorithm, the use of a combination of features extracted from hippocampal images and features already created by the ImageNet network, the removal of inappropriate features from the feature vector, and the use of deep Inception v3 network.
Concolusion: Based on the results, the combination of polygon surrounding the hippocampus features and deep network features can be useful for detection of AD and MCI.

Classification of Chest Radiology Images in Order to Identify Patients with COVID-19 Using Deep Learning Techniques
Marsa Gholamzadeh, Seyed Mohammad Ayyoubzadeh, Hoda Zahedi, Sharareh Rostam Niakan Kalhori,
Volume 15, Issue 3 (8-2021)
Abstract
Background and Aim: Due to the important role of radiological images for identifying patients with COVID-19, creating a model based on deep learning methods was the main objective of this study.
Materials and Methods: 15,153 available chest images of normal, COVID-19, and pneumonia individuals which were in the Kaggle data repository was used as dataset of this research. Data preprocessing including normalizing images, integrating images and labeling into three categories, train, test and validation was performed. By Python language in the fastAI library based on convolution technique (CNN) and four architectures (ResNet, VGG MobileNet, AlexNet), nine models through transitional learning method were trained to recognize patients from healthy persons. Finally, the performance of these models was evaluated with indicators such as accuracy, sensitivity and specificity, and F-Measure.
Results: Of the nine generated models, the ResNet101 model has the highest ability to distinguish COVID-19 cases from other cases with 95.29% sensitivity. Other applied models showed more than 96% accuracy in correctly diagnosis of various cases in test phase. Finally, the ResNet101 model was able to demonstrate 98.4% accuracy in distinguishing between healthy and infected cases.
Conclusion: The obtained accuracy showed the accurate performance of developed model in detecting COVID-19 cases. Therefore, by implementing an application based on the developed model, physicians can be helped in accurate and early diagnosis of cases. an application based on the developed model, physicians can be helped in accurate and early diagnosis of infected cases.

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