COMPUTER-SIMULATION OF GEOMETRY AND HEMODYNAMICS OF CANINE PULMONARY-ARTERIES

Assuming that along the pulmonary arteries, mathematical expectations of branching are equal to matrix (E(i,j); i: parent branch class, j: d aughter branch class number), we made computer drafts of patterns of p ulmonary arterial branching trees from the published data of canine pu lmonary arterial casts with the ''Monte Carlo methods'' by FORTRAN, ca lculating from these data, the numbers of branches, size and resistanc e of the trees. We also analyzed blood flow distribution in a pulmonar y branch according to the pathlength from the entrance of the tree. Th e graphics of the trees were similar to the original arterial casts, a nd numbers of the branches were nearly the same as the previous report ed values. Calculated resistance was reasonable. The rate of blood flo w per unit vessel in the short pathlength group was calculated as 1.5 times that of the long pathlength group of the same diameter. We belie ve that our method of describing the branching pattern matrix (E(i,j)) provides a reasonable simulation of complex branching patterns such a s pulmonary arteries and a useful means to analyze local hemodynamics.