COPD identification and grading based on deep learning of lung parenchyma and bronchial wall in chest CT images

OBJECTIVE: Chest CT can display the main pathogenic factors of chronic obstructive pulmonary disease (COPD), emphysema and airway wall remodeling. This study aims to establish deep convolutional neural network (CNN) models using these two imaging markers to diagnose and grade COPD. METHODS: Subjects who underwent chest CT and pulmonary function test (PFT) from one hospital (n = 373) were retrospectively included as the training cohort, and subjects from another hospital (n = 226) were used as the external test cohort. According to the PFT results, all subjects were labeled as Global Initiative for Chronic Obstructive Lung Disease (GOLD) Grade 1, 2, 3, 4 or normal. Two DenseNet-201 CNNs were trained using CT images of lung parenchyma and bronchial wall to generate two corresponding confidence levels to indicate the possibility of COPD, then combined with logistic regression analysis. Quantitative CT was used for comparison. RESULTS: In the test cohort, CNN achieved an area under the curve of 0.899 (95%CI: 0.853-0.935) to determine the existence of COPD, and an accuracy of 81.7% (76.2-86.7%), which was significantly higher than the accuracy 68.1% (61.6%-74.2%) using quantitative CT method (p < 0.05). For three-way (normal, GOLD 1-2, and GOLD 3-4) and five-way (normal, GOLD 1, 2, 3, and 4) classifications, CNN reached accuracies of 77.4 and 67.9%, respectively. CONCLUSION: CNN can identify emphysema and airway wall remodeling on CT images to infer lung function and determine the existence and severity of COPD. It provides an alternative way to detect COPD using the extensively available chest CT. ADVANCES IN KNOWLEDGE: CNN can identify the main pathological changes of COPD (emphysema and airway wall remodeling) based on CT images, to infer lung function and determine the existence and severity of COPD. CNN reached an area under the curve of 0.853 to determine the existence of COPD in the external test cohort. The CNN approach provides an alternative and effective way for early detection of COPD using extensively used chest CT, as an important alternative to pulmonary function test

A comparative analysis of chronic obstructive pulmonary disease using machine learning, and deep learning

Chronic obstructive pulmonary disease (COPD) is a general clinical issue in numerous countries considered the fifth reason for inability and the third reason for mortality on a global scale within 2021. From recent reviews, a deep convolutional neural network (CNN) is used in the primary analysis of the deadly COPD, which uses the computed tomography (CT) images procured from the deep learning tools. Detection and analysis of COPD using several image processing techniques, deep learning models, and machine learning models are notable contributions to this review. This research aims to cover the detailed findings on pulmonary diseases or lung diseases, their causes, and symptoms, which will help treat infections with high performance and a swift response. The articles selected have more than 80% accuracy and are tabulated and analyzed for sensitivity, specificity, and area under the curve (AUC) using different methodologies. This research focuses on the various tools and techniques used in COPD analysis and eventually provides an overview of COPD with coronavirus disease 2019 (COVID-19) symptoms.

Implementation of a 3D CNN for COPD classification

Segons les prediccions de la Organització Mundial de la Salut (OMS) pels voltants del 2030 la Malaltia Pulmonar Obstructiva Crònica (MPOC) es convertirá en la tercera causa de mort en tot el món. L’MPOC és una patologia que afecta a les vies respiratòries i als pulmons. Avui en dia esdevé crónica i incurable però, és una malaltia tractable i prevenible. Fins ara les proves de diagnòstic usades per a detectar l’MPOC es basen en l’espirometria, aquesta prova, tot i indicar el grau d’obstrucció al pas de l’aire que es produeix en els pulmons, sovint no és molt fiable. És per aquest motiu que s’estan començant a usar tècniques basades en algorismes de Deep Learning per a la classificaió més acurada d’aquesta patologia, basant-se en imatges tomogràfiques de pacients malalts d’MPOC. Les xarxes neuronals convolucionals en tres dimensions (3D-CNN) en són un exemple. A partir de les dades i les imatges obtingudes en l’estudi observacional d’ECLIPSE proporcionades per l’equip de recerca de BRGE de ISGlobal, s’implementa una 3D-CNN per a la classificació de pacients amb risc d’MPOC. Aquest treball té com a objectiu desenvolupar una recerca extensa sobre la recerca actual en aquest àmbit i proposa millores per a l’optimització i reducció del cost computacional d’una 3D-CNN per aquest cas d’estudi concret.Según las predicciones de la Organización Mundial de la Salud (OMS), para alrededor del 2030, la Enfermedad Pulmonar Obstructiva Crónica (EPOC) se convertirá en la tercera causa de muerte en todo el mundo. La EPOC es una enfermedad que afecta las vías respiratorias y los pulmones. En la actualidad, se considera crónica e incurable, pero es una enfermedad tratable y prevenible. Hasta ahora, las pruebas de diagnóstico utilizadas para detectar la EPOC se basan en la espirometría. Esta prueba, a pesar de indicar el grado de obstrucción en el flujo de aire que ocurre en los pulmones, a menudo no es muy confiable. Es por esta razón que se están empezando a utilizar técnicas basadas en algoritmos de Deep Learning para una clasificación más precisa de esta patología, utilizando imágenes tomográficas de pacientes enfermos de EPOC. Las redes neuronales convolucionales en tres dimensiones (3D-CNN) son un ejemplo de esto. A partir de los datos y las imágenes obtenidas en el estudio observacional ECLIPSE proporcionado por el equipo de investigación de BRGE de ISGlobal, se implementa una 3D-CNN para la clasificación de pacientes con riesgo de EPOC. Este trabajo tiene como objetivo desarrollar una investigación exhaustiva sobre la investigación actual en este campo y propone mejoras para la optimización y reducción del costo computacional de una 3D-CNN para este caso de estudio concreto.According to predictions by the World Health Organization (WHO), by around 2030, Chronic Obstructive Pulmonary Disease (COPD) will become the third leading cause of death worldwide. COPD is a condition that affects the respiratory tract and lungs. Currently, it is considered chronic and incurable, but it is a treatable and preventable disease. Up to now, diagnostic tests used to detect COPD have been based on spirometry. Despite indicating the degree of airflow obstruction in the lungs, this test is often not very reliable. That is why techniques based on Deep Learning algorithms are being increasingly used for more accurate classification of this pathology, based on tomographic images of COPD patients. Three-dimensional Convolutional Neural Networks (3D-CNN) are an example of such techniques. Based on the data and images obtained in the observational study called ECLIPSE, provided by the research team at BRGE of ISGlobal, a 3D-CNN is implemented for the classification of patients at risk of COPD. This work aims to conduct extensive research on the current state of research in this field and proposes improvements for the optimization and reduction of the computational cost of a 3D-CNN for this specific case study

Texture Analysis and Machine Learning to Predict Pulmonary Ventilation from Thoracic Computed Tomography

Chronic obstructive pulmonary disease (COPD) leads to persistent airflow limitation, causing a large burden to patients and the health care system. Thoracic CT provides an opportunity to observe the structural pathophysiology of COPD, whereas hyperpolarized gas MRI provides images of the consequential ventilation heterogeneity. However, hyperpolarized gas MRI is currently limited to research centres, due to the high cost of gas and polarization equipment. Therefore, I developed a pipeline using texture analysis and machine learning methods to create predicted ventilation maps based on non-contrast enhanced, single-volume thoracic CT. In a COPD cohort, predicted ventilation maps were qualitatively and quantitatively related to ground-truth MRI ventilation, and both maps were related to important patient lung function and quality-of-life measures. This study is the first to demonstrate the feasibility of predicting hyperpolarized MRI-based ventilation from single-volume, breath-hold thoracic CT, which has potential to translate pulmonary ventilation information to widely available thoracic CT imaging

Advanced Deep Learning for Medical Image Analysis

The application of deep learning is evolving, including in expert systems for healthcare, such as disease classification. Several challenges in the use of deep-learning algorithms in application to disease classification. The study aims to improve classification to address the problem. The thesis proposes a cost-sensitive imbalance training algorithm to address an unequal number of training examples, a two-stage Bayesian optimisation training algorithm and a dual-branch network to train a one-class classification scheme, further improving classification performance

Artificial Intelligence in Image-Based Screening, Diagnostics, and Clinical Care of Cardiopulmonary Diseases

Cardiothoracic and pulmonary diseases are a significant cause of mortality and morbidity worldwide. The COVID-19 pandemic has highlighted the lack of access to clinical care, the overburdened medical system, and the potential of artificial intelligence (AI) in improving medicine. There are a variety of diseases affecting the cardiopulmonary system including lung cancers, heart disease, tuberculosis (TB), etc., in addition to COVID-19-related diseases. Screening, diagnosis, and management of cardiopulmonary diseases has become difficult owing to the limited availability of diagnostic tools and experts, particularly in resource-limited regions. Early screening, accurate diagnosis and staging of these diseases could play a crucial role in treatment and care, and potentially aid in reducing mortality. Radiographic imaging methods such as computed tomography (CT), chest X-rays (CXRs), and echo ultrasound (US) are widely used in screening and diagnosis. Research on using image-based AI and machine learning (ML) methods can help in rapid assessment, serve as surrogates for expert assessment, and reduce variability in human performance. In this Special Issue, “Artificial Intelligence in Image-Based Screening, Diagnostics, and Clinical Care of Cardiopulmonary Diseases”, we have highlighted exemplary primary research studies and literature reviews focusing on novel AI/ML methods and their application in image-based screening, diagnosis, and clinical management of cardiopulmonary diseases. We hope that these articles will help establish the advancements in AI

Hierarchical Amortized Training for Memory-efficient High Resolution 3D GAN

Generative Adversarial Networks (GAN) have many potential medical imaging applications, including data augmentation, domain adaptation, and model explanation. Due to the limited embedded memory of Graphical Processing Units (GPUs), most current 3D GAN models are trained on low-resolution medical images. In this work, we propose a novel end-to-end GAN architecture that can generate high-resolution 3D images. We achieve this goal by separating training and inference. During training, we adopt a hierarchical structure that simultaneously generates a low-resolution version of the image and a randomly selected sub-volume of the high-resolution image. The hierarchical design has two advantages: First, the memory demand for training on high-resolution images is amortized among subvolumes. Furthermore, anchoring the high-resolution subvolumes to a single low-resolution image ensures anatomical consistency between subvolumes. During inference, our model can directly generate full high-resolution images. We also incorporate an encoder with a similar hierarchical structure into the model to extract features from the images. Experiments on 3D thorax CT and brain MRI demonstrate that our approach outperforms state of the art in image generation and clinical-relevant feature extraction.Comment: 12 pages, 9 figures. Under revie