Low-dose CT measurements of airway dimensions and emphysema associated with airflow limitation in heavy smokers: a cross sectional study oleh Dijkstra Akkelies E, Postma Dirkje S, ten Hacken Nick, Vonk Judith M, Oudkerk Matthijs, van Ooijen Peter MA, Zanen Pieter, Mohamed Hoesein Firdaus A, van Ginneken Bram, Schmidt Michael, Groen Harry JM