Relations Between Fractional-Order Model Parameters and Lung Pathology in Chronic Obstructive Pulmonary Disease

• Published in: IEEE transactions on biomedical engineering Vol. 56; no. 4; pp. 978 - 987
• Main Authors: Ionescu, Clara M., De Keyser, Robin
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.04.2009; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adult; Biological tissues; Biometry; Chronic obstructive pulmonary disease; Coal Mining; Damping; Demodulation; Diseases; Elasticity; forced oscillations; fractional-order (FO) models; Humans; identification; input impedance; Lung - pathology; Lung - physiopathology; Lung Compliance; Lungs; Models, Biological; noninvasive; Occupational Diseases - pathology; Occupational Diseases - physiopathology; Pathology; Pulmonary Disease, Chronic Obstructive - pathology; Pulmonary Disease, Chronic Obstructive - physiopathology; Respiratory Function Tests; respiratory mechanics; Respiratory Mechanics - physiology; Signal analysis; Signal processing; Testing; Viscosity
• ISSN: 0018-9294; 1558-2531; 1558-2531
• DOI: 10.1109/TBME.2008.2004966

In this study, changes in respiratory mechanics from healthy and chronic obstructive pulmonary disease (COPD) diagnosed patients are observed from identified fractional-order (FO) model parameters. The noninvasive forced oscillation technique is employed for lung function testing. Parameters on tissue damping and elastance are analyzed with respect to lung pathology and additional indexes developed from the identified model. The observations show that the proposed model may be used to detect changes in respiratory mechanics and offers a clear-cut separation between the healthy and COPD subject groups. Our conclusion is that an FO model is able to capture changes in viscoelasticity of the soft tissue in lungs with disease. Apart from this, nonlinear effects present in the measured signals were observed and analyzed via signal processing techniques and led to supporting evidence in relation to the expected phenomena from lung pathology in healthy and COPD patients.