An essential parameter in assessing
anastomosis quality and grafts petancy is associated with the graft flow rate
measured by the end of the operation. To date, no objective method to determine
the quality of the anastomosis graft and to obtain graft flow rate has been
endorsed by the medical community. This paper describes a non-invasive
technique for measuring the integrity of a venal graft in a coronary artery
bypass upon conclusion of surgery. An in vitro laboratory setup was
designed to illustrate the dynamic conditions in a coronary by-pass graft.
Experiments were conducted for a graft with constant flow and for a graft with
pulsatile flow. Behavior of the vein wall was examined when both ends of the
graft were open to flow, and also when one end of the graft was occluded. The
dynamic behavior of the graft was found to change as a function of graft
patency and venal pressure. A correlation was confirmed between the signal of
oscillation frequency obtained from the camera and the change in pressure at
vein exit.
