in an endeavour to elucidate the anatomical basis for the increased resistance to airflow which characterises the most peripheral conducting air passages in pulmonary emphysema , lumina of nonrespiratory bronchioles of lungs with mainly centrilobular disease were assessed for two- and three-dimensional features by : ( 1 ) determination of percentage conformity of the lumina of individual bronchioles in histological sections to hypothetical planes through cylinders ( ie , ellipses with the same areas and circumferences ) , and ( 2 ) comparison of luminal areas at regular intervals along bronchiolar longitudinal axes .
C0034067
pulmonary emphysema
C0024109
lungs