ABSTRACT
I. Introduction 63
II. Parenchymal Mechanics 64
III. Interaction Between Airways and Parenchyma 66
IV. Malacia of Airways 69
V. Bulk and Shear Modulus 71
VI. Gravitational Effects 71
VII. Anterior-Posterior Gradients in Imaging 72
VIII. Differences Between Supine and Prone Posture 73
IX. “Air Trapping” 75
X. Parenchymal Mechanics in Different Lung Diseases 76
XI. Diaphragm and Chest Wall 78
XII. Conclusion 83
References 83
I. Introduction
The lung, pleura, chest wall, and diaphragm constitute a joint mechanical system,
whose elasticity, viscosity, and musculature work together to enable respiration.
Elasticity, a component of this system, is a vector with a certain size and direc-
tion. The lung itself has an inward vector aimed at diminution, whereas the
thorax, with the lung expanded, has an outward vector aimed at extension. This
interrelation can be described by Eq. (4.1)
