144
Dynamics
of
the
Vascular
System
5.1.2
Nonuniform
Branching and
3-0
Branching Structure
The above considerations of branching structure are not limited to two-
dimensional
(2-D)
vascular networks. In the
2-D
structure, all blood
vessels lie in the same plane. A three-dimensional
(3-D)
structure allows
greater flexibility and expansion. Adding on the nonuniform scheme, the
vascular tree has even greater flexibility in defining its structure.
Fig.
5.1.1
:
A
drawing
of
some
of
the main branches coming
off
from the right coronary
artery
as
it circles the heart. Numbers refer to vascular junctions along the artery. From
Zamir
(2000).
Morphological structures of the branching vascular systems have
been reported by numerous investigators. One such an example is shown
in Fig.
5.1.1,
given by Zamir
(2000).
The main vessel branches from the
right coronary artery are shown, together with the numbers that identify
branching junctions as they arise sequentially along the coronary artery.
These numbers are related to the levels of the arterial tree as illustrated
schematically in Fig.
5.1.2.
This is used for mapping the branches
arising at these junctions. This scheme clearly shows the tree structure
that is nonuniform and incomplete in terms of the order of branching to
terminations
5.1.3).
Both the number of junctions and the level or the
tree are clearly defined.
There are other
differing
branching
structures
found in the
circulations. For instances, the morphometry in the pig coronary venous
system by Kassab et al.
(1994)
and the network anatomy
of
arteries
