5). No differences between the distribution of arteries in both groups were found. As presented in Table 2, except the maximal axial values 1 mm and 2 mm distal the bifurcation, the minimal axial value 3 mm proximal, and the maximal selleck chemical perpendicular value 1mm proximal to the bifurcation were all significantly different. The significance level (p-value < 0.001) was superior in the investigated OES-technique (Table 2). A review of the literature reveals that only few publications are found analyzing the flow in microsurgical end-to-side anastomoses, though a plethora of technical variations
exist.[11, 14, 15, 27, 28] Flow behaviour in approximately true-to-scale silicone rubber models of a conventional technique for end-to-side anastomosis and end-to-side anastomosis using the OES-technique were compared in this study. The measured flow velocities and rates in this experiment were in accordance with intraoperative measurements as described in the literature and the velocity calculations were not affected by the Womersley parameter, since it was
smaller than three.[24, 29-31] The Womersley parameter is a dimensionless parameter in biofluid mechanics and expresses the pulsatile flow frequency in relation to viscous effects and is used for scaling experimental setups.[32-34] Many scientists have studied the flow behaviour in bends and bifurcations by using rigid or www.selleckchem.com/products/epz015666.html simplified models.[35-37] By using the true-to-sclae silicone rubber model, geometry and vessel behavior as well as the fluids used were correct in comparison to human blood vessels as previously published.[22, 38-40] In both models a velocity drop of the maximal axial component between the cross-sections 3 and 1 mm proximal to the reference point was seen (conventional technique model 28.62% and
Liothyronine Sodium OES-model 30.67% of the initial axial velocity component). This velocity drop of the axial component in the main vessel was accompanied with a velocity increase of the perpendicular velocity component, in the branching vessel (conventional technique model 73.8% and 192.45% in the OES-model), representing the flow into the branching vessel, The “perpendicular velocity component” in the branching vessel equates the real axial flow direction of the branching vessel, since the LDA measurements were only performed in x-z-axis. This measured velocity increase was probably due to an increased cross-sectional area in the end-to-side anastomosis of the OES-model. Sen et al. described another end-to-side technique with an increase of the cross-sectional area by performing a diamond-shaped arteriotomy. For further evaluation they performed mathematical analyses to verify their considerations.