Vascular Branching
165
minimum reflection (in the reflection vs. area ratio plot) is shifted to a
larger area ratio, accompanied by a larger phase change.
Table
5.3.1
:Measured and Calculated Vascular Parameters
Ac
zo
E
cm2
cm/s dyn.~.cm-~
106dyn/cm2
Abdominal aorta
0.415
660
1686
5.54
Continuation branch
0.205
710
3671
6.41
Iliac artery
0.115
765
7051
7.44
0.0
-
-25%
-50%
-75%
-100%
Ar
-
Fig.
5.3.3:
Local reflection coefficient is plotted against the reduction in radius. Sharply
increased reflection coefficient is associated with narrowing branching vessel lumen
radius.
The importance of topological geometry and elastic properties at
vascular branching junctions can be easily appreciated from the
measurement of local reflection coefficients involving characteristic
