Relating airway diameter distributions to regular branching asymmetry in the lung.
We study the distribution Pi(n)(D) of airway diameters D as a function of generation N in asymmetric airway trees of mammalian lungs. We find that the airway bifurcations are self-similar in four species studied. Specifically, the ratios of diameters of the major and minor daughters to their parent are constants independent of N until a cutoff diameter is reached. We derive closed form expressions for Pi(N)(D) and examine the flow resistance of the tree based on an asymmetric flow division model. Our findings suggest that the observed diameter heterogeneity is consistent with an underlying regular branching asymmetry.
Majumdar
Arnab
A
Center for Polymer Studies and Department of Physics, Boston University, Massachusetts 02215, USA.
Alencar
Adriano M
AM
Buldyrev
Sergey V
SV
Hantos
Zoltán
Z
Lutchen
Kenneth R
KR
Stanley
H Eugene
HE
Suki
Béla
B
D000818:Animals; D001703:Biophysics / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008168:Lung / Q000473:pathology*; D008953:Models, Anatomic; D008954:Models, Biological; D008956:Models, Chemical; D015233:Models, Statistical; D011652:Pulmonary Circulation; D015656:Respiratory Mechanics; D012143:Respiratory Physiological Phenomena