• Proceedings of the KSME Conference
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• 2001.06a
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• pp.877-882
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• 2001

A finite element analysis of end-to-end artery/PTFE anastomosis has been presented in this study to evaluate the distribution of compliance and stresses in the vicinity of the anastomosis due to any mismatch in compliance characteristics. The artery wall was assumed to be made of linear isotropic material in this simplified model and a nonlinear analysis and convergency study with respect to increasing meshed element numbers were performed with a mean artery pressure loading of the artery-PTFE model. Also, sub-modeling method was introduced to progress the accuracy of the finite element analysis. The results are as follow : 1. A hypercompliant zone on the artery side was observed around 4.0mm from the anastomosis and a high hoop stresses in the wall of artery and PTFE was dominent. 2. An artery displays large deformation so that nonlinear analysis and sub-modeling method was used. 3. An anastomosis with the thinner thickness and larger diameter PTFE (C type) could reduce the compliance disagreement.

• Archives of Reconstructive Microsurgery
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• v.13 no.1
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• pp.74-81
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• 2004

This study was designed to introduce the cross-leg free flap only for vein anastomosis as an alternative salvage method for the reconstruction of severe soft tissue defects in vascular-compromised lower extremities. Four cross-leg free flap reconstructions were performed using the latissimus dorsi muscle to reconstruct soft tissue defects in the lower extremity. The recipient artery was confined to the ipsilateral side and the venous anastomosis was carried out in the contralateral side. Both legs were immobilized together with an external fixator. All patients were males, and had a mean age of 31 years. The mean time of pedicle division was 8.8 days range of 7 to 10 days. The mean size of the flap was 186.5 cm2. All flaps survived after pedicle division without venous congestion. There was no complication in joint stiffness, nor donor site morbidity except for a linear scar. The cross-leg free flap only for vein anastomosis is a refinement of a salvage procedure used for the reconstruction of severe soft tissue defects in vascular-compromised lower extremities.

• Journal of Chest Surgery
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• v.27 no.6
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• pp.489-493
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• 1994

Our patient was a 2.3 kg, male of 33 weeks gestation and spontaneous vaginal delivery. Copious salivary secretion, mild aspiration pneumonia episode due to tracheoesophageal fistula and intermittent cyanotic appearance due to hypoxia were noted shortly after birth. Head up position, frequent upper pouch suction, and adequate fluid and antibiotic therapy were done in incubator. Combined Chest and abdominal film was revealed gas in the stomach and an haziness in right chest with mediastinal shift to the right side. Esophagogram revealed markedly dilated proximal esophagus as blind pouch, and Two dimensional echocardiography showed the Ventricular Septal Defect. The conclusion was congenital esophageal atresia with tracheoesophageal fistula, Vogt-Gross type C, Waterston Risk Category B. Surgical correction with Beardmore anastomosis was performed extrapleurally through 3rd rib bed after the cannulation of umbilical vein and preliminary gastrostomy. The fistula was closed by triple ligation and the upper pouch was then brought down to the presenting surface of the lower esophageal segment that incised, and end to side anastomosis was underwent using interrupt suture placed through the full thickness of both upper pouch and lower esophageal segment. The postoperative patient was well tolerated and recovered uneventfully, permitted feeding on 7th postoperative day after esophagogram.

• Journal of Biomedical Engineering Research
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• v.20 no.5
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• pp.617-624
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• 1999

• Journal of Chest Surgery
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• v.27 no.7
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• pp.603-609
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• 1994

Esophageal atresia is a rare congenital anomaly and it usually associated with tracheo-esophgeal fistula and other congenital anomalies. The first report of esophageal atresia with tracheo-esophageal fistula was done by Thomas Gibson in 1696. In 1941, Haight performed the first successful primary anastomosis for esophageal atresia. These accomplishments opened the gateway for clinical studies that have resulted in reinforcements and improvement in the care of infants born with this anomaly. From January 1986 to April 1994, 14 cases of esophgeal atresia with tracheo-esophgeal fistula were diagnosed in Kyung Hee Uinv. Hospital. There were 9 male and 5 female infants. 12 infants were Gross classification type C and 2 infants were type A. The average body weight was 2.7$\pm$0.4kg and Waterson Category A contained 4 infants, B contained 3 infants and C contained 7 infants. Among these infants, 9 infants were underwent anastomosis procedures. We performed retropleural approach in 6 infants, transpleural approach in 2 infants and 1 infant was performed colon interposition through substernal space.By the method of anastomosis, end-to-side anastomosis was performed in 5 infants, end-to-end anastomosis in 3 infants and esophagocologastrostomy in 1 infant.The former 8 infants were Gross classification type C and the latter was type A. Among the type C infants, 6 infants were anastomosed with one layer interrupted suture and 2 infants with 2 layer interrupted suture. Post- operative death was in 1 infant and 8 infants were discharged with good result and have been in good condition.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.349-354
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• 2004

The effectiveness of a synthetic solution of sodium carboxymethy1cellulose (SCMC) and dextran in the prevention of adhesion formation following intestinal anastomosis of intestine in dogs was elucidated and compared with Interceed. Following induction of adhesion on jejunum of dogs by resection and intestinal anastomosis, the dogs were infused with a synthetic solution of 1% SCMC and 10% dextran in saline in the abdominal cavity at the dose of 5ml/kg of body weight or treated with Interceed membrane. Fourteen days after operation, all the dogs showed adhesion of anastomotic sites to surrounding tissues. The average score of adhesion was 0.50, 0.60 and 0.80 in the dogs infused with the synthetic solution, Interceed membrane and saline solution, respectively. The synthetic solution showed better result of adhesion prevention than Interceed or saline solution. No significant change of body weight, vital signs, hematological values and side effects after operation was found in each group. Therefore, a synthetic solution which is combined with 1% SCMC and 10% dextran in saline can be effectively used for the prevention of adhesion formation comparable to Interceed membrane following intestinal anastomosis in the dogs.

• Journal of Chest Surgery
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• v.44 no.2
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• pp.89-98
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• 2011

Background: Although considerable efforts have been made to improve the graft patency in coronary artery bypass surgery, the role of biomechanical factors remains underrecognized. The aim of this study is to investigate the influences of geometric configurations of the bypass graft on hemodynamic characteristics in relation to anastomosis. Materials and Methods: The Numerical analysis focuses on understanding the flow patterns for different values of inlet and distal diameters and graft angles. The Blood flow field is treated as a two-dimensional incompressible laminar flow. A finite volume method is adopted for discretization of the governing equations. The Carreau model is employed as a constitutive equation for blood. In an attempt to obtain the optimal aorto-coronary bypass conditions, the blood flow characteristics are analyzed using in vitro models of the end-to-side anastomotic angles of $45^{\circ}$, $60^{\circ}$ and $90^{\circ}$. To find the optimal graft configurations, the mass flow rates at the outlets of the four models are compared quantitatively. Results: This study finds that Model 3, whose bypass diameter is the same as the inlet diameter of the stenosed coronary artery, delivers the largest amount of blood and the least pressure drop along the arteries. Conclusion: Biomechanical factors are speculated to contribute to the graft patency in coronary artery bypass grafting.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6733-6736
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• 2014

Background: Despite the growing acceptance of laparoscopic colon surgery, an abdominal incision is needed to remove the specimen and perform an anastomosis. Recently, natural orifice specimen extraction (NOSE) and intracorporeal anastomosis have been proposed to minimize abdominal wall trauma and improve the quality of laparoscopic colon resections Objective: To evaluate the feasibility and safety of a new approach combining intracorporeal delta-shaped anastomosis and transvaginal specimen extraction for totally laparoscopic sigmoid colectomy. Materials and Methods: Mobilization of bowel and dissection of lymph nodes were performed laparoscopically. After both proximal and distal incisal edges about 10.0 cm distance from sigmoid neoplasm were transected with an Endoscopic Linear Cutter-Straight, a small incision about 1.0 cm was created on the each colon wall of the contralateral side of the mesentery. Then anvils of an Endoscopic Linear Cutter-Straight were inserted into each colon through the small incisions, and incision and anastomosis between the walls of each colon were performed with a linear stapler. A V-shaped anastomosis was made on the wall and the remnant openings was reclosed with the Endoscopic Linear Cutter-Straight. The culdotomy was enlarged with laparoscopic ultrasound dissector. Transvaginal extraction of specimens was accomplished through a wound protector. Results: Surgery was performed for 11 patients with sigmoid cancer. No intraoperative complications or conversions occurred. The mean operating time was 132 min. All the patients were treated laparoscopically without any postoperative complications. Conclusions: The procedures of intracorporeal delta-shaped anastomosis and transvaginal specimen extraction are safe and oncologically acceptable for selected colon cancer cases.

• Journal of Biomedical Engineering Research
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• v.24 no.2
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• pp.113-119
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• 2003

In this paper we introduced optimized deformed shape to prevent the blood vessel disease caused by the discord of deformed shape in the end-to-end anastomosis. This study considered the preliminary deformed shape induced by suture in the anastomosis of artery and PTFE, artificial blood vessel, with different diameters. Then we analyzed the final deformed shape of the anastomotic part under the systolic blood pressure. 120mmHg(16.0kPa). The final deformed shape of the anstomotic part was analyzed with respect to the change of initial diameter ratio(R$_{I}$) and the PTFE thickness. Equivalent and circumferential stresses induced by the systolic blood pressure in the anastomosis were also analyzed with respect to the initial diameter ratio(R$_{I}$). The results obtained were as follows : 1. Considering the preliminary deformed shape induced by suture and the systolic pressure in the anastomosis, not intimal hyperplasia, the optimal initial diameter ratio(R$_{I}$) was 1.073. 2. As the initial diameter ratio(R$_{I}$) became larger, higher equivalent and circumferential stresses were induced. And all the maximum stresses occurred on the side of PTFE 0.4mm apart from the anastomosis.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.104-108
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• 1995

Von Mises stress and compliance distribution was evaluated using a finite element analysis on the anastomosis of an artery with length of 20mm, inner diameter of 4mm, thickness of 0.5mm and a PTFE graft with length of 5.7mm, Inner diameter of 2mm. thickness of 0.2mm. When anastomotic angle was taken as $45^{\circ}$ and inner pressure of $1330\;dyne/mm^2$ was applied inside the 2 conduits. From the analysis results were obtained as follows. (1)Artery diameter increased in both horizontal x and vertical y directions and the magnitude of that in x direction was bigger than in y direction. (2) The compliance was maximum on the anastomosis. especially on that with acute angle. This reduced approaching to the right or left end. (3) The equivalent stress was maximum on top in the y direction and winimum on the nodes around $110^{\circ}$ in circumferential direction from the top. (4) The equivalent stress was maximum in the vicinity of anastomosis with acute angle along the longitudinal direction of the artery. This trend was also observed along the PTFE graft.