• 한국정밀공학회지
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• 제20권2호
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• pp.192-198
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• 2003

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.Omm from the anastomosis and a high hoop stresses in the wall of artery and PTFE was dominant. 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 (B type) could reduce the compliance disagreement.

• Archives of Plastic Surgery
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• 제46권4호
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• pp.344-349
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• 2019

Background Lymphaticovenous anastomosis is an important surgical treatment for lymphedema, with lymphaticovenous side-to-end anastomosis (LVSEA) and lymphaticovenous end-to-end anastomosis being the most frequently performed procedures. However, LVSEA can cause lymphatic flow obstruction because of regurgitation and tension in the anastomosis. In this study, we introduce a novel and simple procedure to overcome this problem. Methods Thirty-five female patients with lower extremity lymphedema who underwent lymphaticovenous anastomosis at our hospital were included in this study. Eighty-five LVSEA procedures were performed, of which 12 resulted in insufficient venous blood flow. For these 12 anastomoses, the proximal lymphatic vessel underwent clipping after the anastomotic procedure and the venous inflow was monitored. Subsequently, the proximal ligation after side-to-end anastomosis recovery (PLASTER) technique, which involves ligating the proximal side of the lymphatic vessel, was applied. A postoperative evaluation was performed using indocyanine green 6 months after surgery. Results Despite the clipping procedure, three of the 12 anastomoses still showed poor venous inflow. Therefore, it was not possible to apply the PLASTER technique in those cases. Among the nine remaining anastomoses in which the PLASTER technique was applied, three (33%) were patent. Conclusions Our findings show that achieving patent anastomosis is challenging when postoperative venous inflow is poor. We achieved good results by performing proximal ligation after LVSEA. Thus, the PLASTER technique is a particularly useful recovery technique when LVSEA does not result in good run-off.

• 한국간담췌외과학회지
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• 제27권1호
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• pp.49-55
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• 2023

Backgrounds/Aims: Data regarding outcomes of endoscopic retrograde cholangiography (ERC) in liver transplant (LT) recipients with biliary-enteric (BE) anastomosis are limited. We report outcomes of ERC and percutaneous transhepatic biliary drainage (PTBD) as first-line therapies in LT recipients with BE anastomosis. Methods: All LT recipients with Roux-BE anastomosis from 2001 to 2020 were divided into ERC and PTBD subgroups. Technical success was defined as the ability to cannulate the bile duct. Clinical success was defined as the ability to perform cholangiography and therapeutic interventions. Results: A total of 36 LT recipients (25 males, age 53.5 ± 13 years) with Roux-BE anastomosis who underwent biliary intervention were identified. The most common indications for a BE anastomosis were primary sclerosing cholangitis (n = 14) and duct size mismatch (n = 10). Among the 29 patients who initially underwent ERC, technical success and clinical success were achieved in 24 (82.8%) and 22 (75.9%) patients, respectively. The initial endoscope used for the ERC was a single balloon enteroscope in 16 patients, a double balloon enteroscope in 7 patients, a pediatric colonoscope in 5 patients, and a conventional reusable duodenoscope in 1 patient. Among the 7 patients who underwent PTBD as the initial therapy, six (85.7%) achieved technical and clinical success (p = 0.57). Conclusions: In LT patients with Roux-BE anastomosis requiring biliary intervention, ERC with a balloon-assisted enteroscope is safe with a success rate comparable to PTBD. Both ERC and PTBD can be considered as first-line therapies for LT recipients with a BE anastomosis.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.442-447
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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 in the vicinity of the anastomosis due to any mismatch in compliance characteristics. But, In these studies it was assumed that the artery and PTFE have the simple cylindrical shape representing the fatty tissue surrounding the coronary artery. And the fatty tissue was considered as the elastic surrounding materials in the finite element analysis. The simulation results were obtained as follows : 1. A fatty tissue was effect to reduce the compliance mismatch in the vicinity of a artery/PTFE anastomosis of different material because a hypercompliant zone become narrorw and a compliance discrepancy decrease between the artery and the PTFE about 70%. And radial direction displacement distribution with respect to distance in the vicinity of a artery/PTFE anastomosis was similiar. 2. The variation of PTFE thckness reduce the compliance mismatch in the vicinity of a artery/PTFE anastomosis about 25%.

• 대한기관식도과학회지
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• 제7권1호
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• pp.9-13
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• 2001

Background： Tracheal resection and end-to-end anastomosis are the preferred treatment for tracheal tumor or tracheal stenosis. Absorbable suture material has been commonly used in case of tracheal anastomosis. But anastomosis technique is controversial. This experimental study compared between interrupted suture and continuous suture using Polydioxanone (PDS) absorbable suture material after tracheal resection and end-to-end anastomosis in rabbits. Methods : Twenty-four rabbits were used, divided into two groups of 12 animals each. The trachea was resected and then anastomosed with continuous 6-0 polydioxanone (PDS) (group 1), and intermittent 6-0 polydioxanone (PDS) (group 2). The animals were followed up for 6 months. Stenosis of the trachea was assessed at the time of death. Results : In two groups, anteroposterior diameter, transverse diameter, cross sectional area, and perimeter were greater in group 2 than in group 1 but, not significantly different. In addition, histologic findings were not different in two groups. Conclusions : This study suggest that stenosis after tracheal resection and end-to-end anastomosis using absorbable polydioxanone (PDS) suture material be not significantly different in both groups.

• 대한기관식도과학회지
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• 제4권1호
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• pp.27-34
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• 1998

Despite improvement in respiratory care, including use of low pressure and high volume cuffed tubes, tracheal stenosis remains a serious complication after a long-term tracheal intubation and tracheostomy. In such patients, tracheal resection and primary anastomosis is still considered ideal therapeutic modality. Between 1989 and 1997, we performed tracheal resections with end-to-end anastomosis on 14 patients with no operative mortality and some morbidity. Tracheal stenosis was caused by tracheostomy in nine patients, by endotracheal intubation in three patients and by thyroid carcinoma in two patients. The length of stenosis was various from 2cm to 4.5cm. All patient underwent segmental tracheal resection and primary anastomosis(14 patients) and additional procedures were cricoid cartilage reconstruction(2 patients), suprahyoid laryngeal release(3patients), carinal release technique(2 patients) and arytenoidectomy(2 patients). We have nine complications: granulona at anastomosis site in four patients, vocal cord palsy in two patients and restenosis, pneumonia, skin necrosis in each of those patients. The granuloma was removed by bronchoscopic forceps(4 patients). Vocal cord palsy was treated by arytenoidectorny(2 patients), restenosis by T-tube insertion, pneumonia by antibiotics and skin necrosis was treated by skin graft. We reviews our expenence of clinical features of tracheal stenosis and surgical treatment by tracheal one-to-end anastomosis with additional procedures to avoid postoperative complications for sucessful results.

• Journal of Minimally Invasive Surgery
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• 제21권4호
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• pp.180-182
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• 2018

The frequency of anastomotic leakage after gastrectomy is reported to be 0.9~8%. To reduce deleterious outcomes of anastomotic leakage, we devised the "Omental Free-shaped Flap Reinforcement On Anastomosis and Dissected area" procedure not only to prevent fatal complications following anastomotic leakage but also to promote vascularity of anastomoses and other expected oncological benefits. This video illustrates the surgical procedure following a totally laparoscopic distal gastrectomy. After completion of the anastomosis, the remaining omentum was mobilized upward and divided into two sections. We placed the left section of the omental flap under the anastomosis between the stomach and pancreas. Finally, we grasped and curved the tip of the section to cover the anastomosis from behind, and we placed the right section of the omental flap above the anastomosis. These two sections were approximated with clips to the anterior wall of the stomach. The patient was discharged without complications.

• Archives of Reconstructive Microsurgery
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• 제3권1호
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• pp.45-53
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• 1994

Suture microvascular anastomosis is time-consuming and tedious and demands long and continuous training. Techinique of anastomosis of microvessel was presented interrupted suture and continuous suture. Recently the unilink instrument system is created as a fast and simple method to achieve high patency rates without long and continuous training in the anastomosis of small vessels. The author experimentally studied the femoral artery of 20 mice(0.5-1.0mm, av. 0.7mm), the femoral vein of 20 mice(0.8-1.6mm, av. 1.2mm) after anastomosis with interrupted suture in 20 cases and continuous sutre in 20 cases. For the unilink apparatus we used the carotid arteries of 15 cases in 14 rabbits(1.0-1.6mm, av. 1.3mm) and facial veins of 12 cases in 14 rabbits(0.9mm-2.2mm, av. 1.5mm). A total of 27 arterial and venous anastomoses were performed. We examined the postoperative patency at immediate, 2 weeks, and 8 weeks. The results were as followings, 1. In the arterial anastomosis the rate of patency was 90%(18/20) in interrupted suture, 90%(18/20) in continuous suture and 93%(13/15) in unilink apparatus. In the venous anastomosis the rate of patency was 90%(18/20) in interrupted suture, 80%(16/20) in continuous suture and 100%(9/9) in unilink apparatus. 2. The mean time for completion of the arterial anastomosis were 12.2 minutes in interrupted suture group, 10.3 minutes in continouous suture group and 8.5 minutes in unillnk apparatus group. The mean time for completion of the venous anastomosis were 13.6 minutes in interrupted suture group, 11.0 minutes in continuous suture group and 6.2 minutes in unilink apparatus group. 3. At the histological examination of suture group, hyperplastic reaction of middle layer and subintimal hyperplasia were observed. In unilink apparatus group, the endothelium layer was continued and the thickness of vessel wall was decreased due to moderate atrophy of the media and mild degree of nonspecific chronic inflammation were seen around the unilink apparatus. 4. No significants was noticied in foreign body reaction among the interrupted, continuous and unilink apparatus group. 5. A case of the arterial anastomosis was released with acting out at 15 minutes after operation. 6. The important factors in the technical problems were accurate apposition of the cut vessel edges in suture group and the proper selection of the ring size and optimal fitting between two rings in unilink apparatus group. Even though the outer diamater of vessel in suture group was different from that in unilink apparatus group the unilink method provides a very safe, fast, and simple way to perform microvascular anastomoses especially in anastomosis of vein. But howerver suture was needed in vessels below 1 mm outer diamater. In that situation continuous suture was benefit than the interrupted suture in operation time.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.977-978
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• 2009

• Archives of Reconstructive Microsurgery
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• 제2권1호
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• pp.82-92
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• 1993

A comparative study was undertaken to evaluate the contact Neo-dymium : yttrium aluminum garnet(Nd:YAG) laser system for vascular anastomosis of small caliber blood vessels(diameter 0.5-1.2 mm) in the animal model. In this study 40 femoral arteries and 40 femoral veins of Sprague-Dawley rats were anastomosed by contact laser assisted microvascular anastomosis(LAMA) utilizing 3 stay sutures which were placed 120 degrees apart and the intervals welded with contact Nd:YAG laser unit, conventionally sutured anastomosis(CSA) served as controls. The time needed for vascular anastomosis, patency rate(immediate postoperative, postoperative 2nd day, postoperative 1 week, postoperative 4 weeks), gross and microscopic evaluations were compared to conventional microsurgical suture technique. The results are as follows: 1. Postoperative patency rate was 82.5% for femoral artery and 75% for femoral vein by contact LAMA technique compared to 90% and 75% by CSA technique at postoperative 4 weeks. 2. Less time-consumed for arterial anastomosis by 6 minutes 23 seconds and venous anastomosis by 8 minutes 55 seconds with contact LAMA technique compared to CSA technique. 3. Grossly almost complete healing had taken place by postoperative 1 week by contact LAMA technique. 4. Aneurysm formation was 5% for femoral artery and 15% for femoral vein by contact LAMA technique compared to 5% and 10% respectively by CSA technique. 5. Microscopically, re-endothelization was complete by postoperative 7th day by contact LAMA technique. There was less medial hypertrophy and hyperplasia and also less inflammatory response compared to CSA.