[The changes in airway structure associated with reduced FEV1].
The purpose of this study is to clarify the changes in the small airways associated with reduced forced expiratory volume in one second (FEV1). We compared the structure of the membranous and respiratory bronchioles of resected lungs from 111 patients with a normal predicted FEV1 to the structure of these airways from 45 patients with an FEV1 reduced below the 95% confidence limits for height and age. Membranous and respiratory bronchioles of less than 2 mm in internal diameter were counted and their diameter and wall thickness were measured. The data show that there were more membranous bronchioles of internal diameter less than 0.4 mm in patients with reduced FEV1. The walls of membranous bronchioles were not increased in thickness but there was an increase in the ratio of wall thickness to lumen diameter. The wall thickness of respiratory bronchioles was increased in the obstructed group and there was also an increase in the ratio of wall thickness to lumen diameter in these airways. We conclude that the patients with obstructive lung disease have a greater increase in wall thickness than can be explained by a reduction in airway support due to emphysema and suggest that the airways obstruction in these patients is due to thickening of the wall and narrowing of the lumen by a chronic inflammatory process.
Matsuba
K
K
Research Institute for Diseases of the Chest, Faculty of Medicine, Kyushu University, Fukuoka.
Ikeda
T
T
Shirakusa
T
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000403:Airway Resistance; D001980:Bronchi / Q000473:pathology*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged