Membranous bronchioles and connective tissue network of normal and emphysematous lungs. Verbeken, E. K., M. Cauberghs, and K. P. Van De Woestijne. Laboratorium voor Pathologische Ontleedkunde I en Laboratorium voor Pneumologie, Universitaire Ziekenhuizen St. Rafa[diaeresis]el en Gasthuisberg, B-3000 Leuven, Belgium
APStracts 3:0382A, 1996.
Three dimensional reconstructions of the septal system of normal human lungs revealed that airways course within the interlobular septa, i.e. between the two blades formed by the peripheral boundaries of adjacent lobuli of whatever order, and enter the supplied pulmonary unit at its side. This is not in keeping with the classical view of a peripheral airway in the center of a lung unit and submitted to radial traction by attached alveolar septa. The basis design of the lung fibrous scaffold appears to be in conformity with the laws of fractal geometry. Similar reconstructions in centrilobular emphysema disclosed tortuosities of both intraacinar and interlobular septa, with consequent distortions of the corresponding intraseptal bronchioles, and collapse of lung units of different size. It is suggested that in centrilobular emphysema, competition for space, besides intrinsic airways narrowing due to inflammation, is a cause of flow limitation.

Received 10 July 1995; accepted in final form 18 July 1995.
APS Manuscript Number A739-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 29 August 1996