Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification

Deep Learning is a very active and important area for building Computer-Aided Diagnosis (CAD) applications. This work aims to present a hybrid model to classify lung ultrasound (LUS) videos captured by convex transducers to diagnose COVID-19. A Convolutional Neural Network (CNN) performed the extrac...

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Main Authors: Bruno Barros, Paulo Lacerda, Célio Albuquerque, Aura Conci
Format: Article
Language:English
Published: MDPI AG 2021-08-01
Series:Sensors
Subjects:
Online Access:https://www.mdpi.com/1424-8220/21/16/5486
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author Bruno Barros
Paulo Lacerda
Célio Albuquerque
Aura Conci
author_facet Bruno Barros
Paulo Lacerda
Célio Albuquerque
Aura Conci
author_sort Bruno Barros
collection DOAJ
description Deep Learning is a very active and important area for building Computer-Aided Diagnosis (CAD) applications. This work aims to present a hybrid model to classify lung ultrasound (LUS) videos captured by convex transducers to diagnose COVID-19. A Convolutional Neural Network (CNN) performed the extraction of spatial features, and the temporal dependence was learned using a Long Short-Term Memory (LSTM). Different types of convolutional architectures were used for feature extraction. The hybrid model (CNN-LSTM) hyperparameters were optimized using the Optuna framework. The best hybrid model was composed of an Xception pre-trained on ImageNet and an LSTM containing 512 units, configured with a dropout rate of 0.4, two fully connected layers containing 1024 neurons each, and a sequence of 20 frames in the input layer <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>(</mo><mn>20</mn><mo>×</mo><mn>2018</mn><mo>)</mo></mrow></semantics></math></inline-formula>. The model presented an average accuracy of 93% and sensitivity of 97% for COVID-19, outperforming models based purely on spatial approaches. Furthermore, feature extraction using transfer learning with models pre-trained on ImageNet provided comparable results to models pre-trained on LUS images. The results corroborate with other studies showing that this model for LUS classification can be an important tool in the fight against COVID-19 and other lung diseases.
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spelling doaj.art-4cc540db8452421ab1bb78220d9f12a52023-11-22T09:40:38ZengMDPI AGSensors1424-82202021-08-012116548610.3390/s21165486Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video ClassificationBruno Barros0Paulo Lacerda1Célio Albuquerque2Aura Conci3Institute of Computing, Campus Praia Vermelha, Fluminense Federal University, Niterói 24.210-346, BrazilInstitute of Computing, Campus Praia Vermelha, Fluminense Federal University, Niterói 24.210-346, BrazilInstitute of Computing, Campus Praia Vermelha, Fluminense Federal University, Niterói 24.210-346, BrazilInstitute of Computing, Campus Praia Vermelha, Fluminense Federal University, Niterói 24.210-346, BrazilDeep Learning is a very active and important area for building Computer-Aided Diagnosis (CAD) applications. This work aims to present a hybrid model to classify lung ultrasound (LUS) videos captured by convex transducers to diagnose COVID-19. A Convolutional Neural Network (CNN) performed the extraction of spatial features, and the temporal dependence was learned using a Long Short-Term Memory (LSTM). Different types of convolutional architectures were used for feature extraction. The hybrid model (CNN-LSTM) hyperparameters were optimized using the Optuna framework. The best hybrid model was composed of an Xception pre-trained on ImageNet and an LSTM containing 512 units, configured with a dropout rate of 0.4, two fully connected layers containing 1024 neurons each, and a sequence of 20 frames in the input layer <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>(</mo><mn>20</mn><mo>×</mo><mn>2018</mn><mo>)</mo></mrow></semantics></math></inline-formula>. The model presented an average accuracy of 93% and sensitivity of 97% for COVID-19, outperforming models based purely on spatial approaches. Furthermore, feature extraction using transfer learning with models pre-trained on ImageNet provided comparable results to models pre-trained on LUS images. The results corroborate with other studies showing that this model for LUS classification can be an important tool in the fight against COVID-19 and other lung diseases.https://www.mdpi.com/1424-8220/21/16/5486COVID-19CNNDeep LearningLSTMlung ultrasoundneural networks
spellingShingle Bruno Barros
Paulo Lacerda
Célio Albuquerque
Aura Conci
Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification
Sensors
COVID-19
CNN
Deep Learning
LSTM
lung ultrasound
neural networks
title Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification
title_full Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification
title_fullStr Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification
title_full_unstemmed Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification
title_short Pulmonary COVID-19: Learning Spatiotemporal Features Combining CNN and LSTM Networks for Lung Ultrasound Video Classification
title_sort pulmonary covid 19 learning spatiotemporal features combining cnn and lstm networks for lung ultrasound video classification
topic COVID-19
CNN
Deep Learning
LSTM
lung ultrasound
neural networks
url https://www.mdpi.com/1424-8220/21/16/5486
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AT paulolacerda pulmonarycovid19learningspatiotemporalfeaturescombiningcnnandlstmnetworksforlungultrasoundvideoclassification
AT celioalbuquerque pulmonarycovid19learningspatiotemporalfeaturescombiningcnnandlstmnetworksforlungultrasoundvideoclassification
AT auraconci pulmonarycovid19learningspatiotemporalfeaturescombiningcnnandlstmnetworksforlungultrasoundvideoclassification