Tailor-Made and Biodegradable Vascular Scaffolds - Microsurgery: Advances, Simulations, and Applications - page 265

electrospinning [5-10]. Electrospinning is suitable for the short-
time fabrication of sheet-like or straight cylindrical scaffolds. It is not
suitable for scaffolds with complex conigurations such as curvature
or bifurcations.
Matsuda et al. also developed a vascular graft with biomimetic
elasticity especially in its pressure-diameter relationship. The
main technological feature of this mechanoactive graft is the use
of a durable synthetic elastomer (SPU) coupled with laser-ablated
microfabrication with CAD and CAM [11, 12]. Circular pores were
generated on the surface of SPU tubes by excimer laser (KrF: 248
nm) with various pore densities (wall thickness: 100 μ m, length:
2 cm, inner diameter: 1.5 mm, pore diameter: 100 μ m). The high
pore-density tube produced compliance similar to that of human
coronaries within the physiological pressure range [13]. They
extended this research to the imitation of pressure-diameter
property of native artery. Artery indicates unique biomechanical
properties: large inlation in the low-pressure regions, gradually
reduced inlation in the physiological pressure regions, and little
inlation in the high-pressure regions, which is termed the “J curve”
in the pressure-diameter plot.
They achieved this property in vitro by developing a coaxial
double-tubular compliant graft. The coaxial compliant graft was
assembled by inserting the high-compliance inner tube into the low-
compliance outer tube. By increasing the intraluminal hydrodynamic
pressure, the inner tube inlates in the low-pressure regions. After
the inner tube made contact with the outer tube, both tubes inlated
together gradually in the high-pressure regions. This fabricated
coaxial double-tubular graft exhibited the J-curve mimicking that of
canine carotid arteries.
Another major way to fabricate biodegradable and porous
scaffolds is porogen leaching method using a casting mold. Recently,
Gao et al. developed a way to fabricate small-diameter vascular graft
using PGS [14]. At this moment, we presume that this method has
the highest potential to meet all the criteria of (i) biodegradability,
(ii) porosity, (iii) complex coniguration such as bifurcations, owing
to the use of the casting mold.
However, none of previous technologies focused on the precise
reconstruction of vascular coniguration. As a requirement for
scaffolds, it is very important to recreate the coniguration of the
patient's vascular structure. Vascular scaffolds with biomimetic