Papers by Keyword: Anastomosis

Abstract: To investigate the application of improved radial arteryand cephalic vein anastomosis in the fistulation for the hemodialysis in patients, 80 cases of patients with chronic renal failure were randomly divided into two groups, a control group and an improved group. The procedure for the wrist radial arteryand cephalic vein anastomosis was improved, in which in a way of continuously everted full-thickness suture, the distal end of radial artery and the proximal end of cephalic vein were anastomosed. The patients were examined by the different methods before the surgery to evaluate the patients’conditions. Patients in the improved group underwent the anastomosis of the wrist radial artery and cephalic vein in a way of continuously everted full-thickness suture, and those in the control group underwent the anastomosis in the conventional way. The improved procedure showed some advantages, such as reduced anastomotic blood leakage, good alignment of the arteryand veinwalls, shortened vascular suture time, and less knot of sutures at the anastomotic junction. The improved procedure should be appropriated for the patients whose Allen's test is negative and cephalic vein is good in the blood flow and filling. However, the weak blood reflux of the distal end of radial artery should bethe contraindication for the improved procedure.

Abstract: In order to keep the stability of tool’s removal function, it is required that the anastomosis be tight between the tool and workpiece surface in Computer-controlled Optical Surfacing (CCOS). In this paper, the influence of tool’s character on anastomosis status is firstly studied. The relation model on the ratio of radius to thickness, Young's modulus of the tool, normal asphericity and normal arc height of workpiece surface is established, and the macroscopical condition of tight anastomosis is derived in aspheric optics machining. According to the microcosmic distribution of surface error, the mathematical relation between anastomosis error and removal rate is researched. In the end, the influence rule of anastomosis status on the convergence ratio of residual error is analyzed in machining zone. Based on the conclusion of machining instance, it is found that workpiece material would be fast removed in middle contact zone when the peak value of tool’s removal function locates in its center position.

Abstract: A soluble intralumenal stent for vascular anastomosis was prepared from glucose, Dextran-40 and heparin. The solubility of the stent was tested in vitro and in vivo. Animal tests were carried out with femoral arteries of rabbits. In comparison with the literature reported surgar and poly(ethylene glycol, PEG) stents, shorter dissolving time and higher patency (or survival) rate were obtained. Cell culture experiments suggested that the heparin containing glucose and Dextran-40 stent (H-sugar) had no irritation and toxicity to the endothelia cells. No thrombosis was observed from the in vivo tests in 2 months after the anastomosis. Such a heparin containing sugar stent is a promising candidate for fast sutureless anastomosis of vessels in non-trauma surgery.