Morphological and functional imaging in COPD with CT and MRI: present and future

Abstract

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide. COPD is defined by irreversible airflow obstruction. It is a heterogeneous disease affecting the airways (i.e. chronic bronchitis, airway collapse), the parenchyma (i.e. hyperinflation, air trapping and emphysematous destruction) as well as the vasculature (i.e. hypoxic vasoconstriction, rarefication and pulmonary arterial hypertension) with different severity during the course of the disease. These different aspects of COPD can be best addressed by imaging using a combination of morphological and functional techniques. Three-dimensional high-resolution computed tomography (3D-HRCT) is the technique of choice for morphological imaging of the lung parenchyma and airways. This morphological information is to be accomplished by functional information about perfusion, regional lung mechanics, and ventilation mainly provided by MRI. The comprehensive diagnostic possibilities of CT complemented by MRI will allow for a more sensitive detection, phenotype-driven characterization and dedicated therapy monitoring of COPD as presented in this review.

Emphysema diagnosis using X-ray dark-field imaging at a laser-driven compact synchrotron light source

“…The disease is characterized by airflow limitation and lung inflammation as a response to noxious particles or gases, resulting in a progressive deterioration in lung function and health-related quality of life (3,4).…”

Pressure Loss Coefficients for Asymmetric Bifurcations of Pulmonary Airways with Predetermined Flow Distributions

“…D ratio is varied from 0.4 to 1.0. The entry and exit terms of Equation 6 were taken at one diameter upstream (L/D=-1) and 19 diameters downstream (L/D=19) of the bifurcation to allow for fully developed flow. In all, 100 CFD simulations were performed (Table 1) with two K values being calculated per simulation, one for the left (diseased) branch and one for the right (healthy) branch.…”

“…It is therefore of interest to examine the pressure losses within diseased airways. Heterogeneous airway obstructions are associated with a variety of respiratory diseases, including asthma, COPD, and cystic fibrosis, and can limit ventilation of obstructed regions of the lung [3][4][5][6].…”

High resolution tomographic imaging of the alveolar region of the mammalian lung

“…Airways within the parenchyma-customarily called acinar/alveolar ducts-on the other hand, are not pipelike; they are formed by entrance rings of alveoli opening into a common passageway. Currently, enormous efforts (e. g. , [63][64][65][66][67][68][69][70][71][72][73][74]) are devoted to reconstructing the conducting airway network in three dimensions (3d), facilitated by rapid advancement of imaging technologies (e. g. , micro-Computed Tomography (µCT), hyperpolarized-gas Magnetic Resonance Imaging (MRI) (HHe 3 MRI, etc. ), as well as a rapid increases in computing power.…”