At 10 locations (including the three-point suture site), sutures are inserted around the circumference of the vessel, with the thread extending into the lumen at a height of 0.025 mm and length of 0.115 mm. The mesh consisted of 723,211 elements and 201,167 nodes in Type I 722,622 elements and 201,394 nodes in Type II and 700,890 elements and 198,467 nodes in Type III ( Fig.
#WALL SHEAR STRESS PARAVIEW SOFTWARE#
These geometries were constructed by using computer-aided design (CAD) software (Fusion 360, Autodesk, Inc., USA), and the computational meshes were created using commercial meshing software (ANSYS ICEM16.0, ANSYS Japan, Tokyo, Japan). The height of the crossing threads at the three-point suture in Type II was 0.02 mm. In Type I, 2 sutures out of three were lined up in parallel with the three-point suture at intervals of 0.015 mm and in Type III, at intervals of 0.05 mm. In Type III, it is formed by a single continuous stitch.Īt 10 locations (including a three-point suture), sutures were placed around the junction of the vessels, with the thread extending into the lumen at the height of 0.025 mm and length of 0.115 mm. In Type II, it is formed by 2 stitches in an X-shape. In Type I, the suture is formed by three stitches. A single continuous ligature through the vascular wall (Type III).
Two single-knot sutures forming an X-shape (Type II).The three types of sutures to be used at the three-point suture site during the tapering technique were defined ( Fig. The diameter of the suture thread is equivalent to 10-0 nylon. We established a model of vascular anastomosis 2 mm in diameter with the suture thread of 0.03 mm diameter. From the results, we investigated the effects of each suture thread on blood flow at the microanastomosis site to ascertain the most appropriate method for the three-point suture site.
Therefore, we compared three different types of suture techniques for the three-point suture site by using computational fluid dynamics (CFD), to evaluate the suture thread's effect from a hemodynamic point of view. If the number of sutures is increased to prevent such leakage, there is the risk of thrombosis. This three-point suture site is susceptible to blood leakage. As this portion is sutured together to reduce the vessel diameter, a three-point suture is always present when the vessels are anastomosed. 3 The larger-diameter vessel is cut obliquely in a funnel shape. The tapering technique is often used when microsurgeons perform anastomoses of the vessels with large discrepancies. The present results suggest that Type III is the best three-point suturing method for the tapering technique.Īlthough microsurgery has become a common procedure, 1,2 the choice of the technique still depends on microsurgeons’ experience rather than evidence. The maximum oscillatory shear index was highest in Type II, and lowest in Type III. In all 3 types, the highest wall shear stress was recorded at the suture peak protruding into the vessel. Streamline disruption was most severe for Type II. The streamline, wall shear stress, and oscillatory shear index at the anastomosis site were measured using a previously prepared venous model. Vascular models of these 3 types were created.
When the tapering technique is used, a three-point suture is always present. The tapering technique is one of the useful methods of anastomosing 2 vessels with large discrepancies during microanastomoses.