• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.2
• /
• pp.192-198
• /
• 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.

• Korean Journal of Bronchoesophagology
• /
• v.10 no.1 s.19
• /
• pp.41-45
• /
• 2004

Tracheostomy and endotracheal intubation are often performed in patients with acute and chronic respiratory failure. Recently, the incidence of iatrogenic tracheal stenosis has increased. Tracheal resection and end-to-end anastomosis would be one of the most physiologic treatment options for severe tracheal stenosis. Also, this treatment can be applied to the management of trachea invaded by thyroid cancer and tracheal neoplasm. The authors aimed to analyze the outcomes of end-to-end anastomosis of trachea following segmental resection in tracheal stenosis and tracheal invasion of cancer that we have recently experienced. Materials and methods Authors retrospectively studied 19 cases treated by tracheal resection with end-to-end anastomosis between Feburuary 1996 and January 2003. 12 patients had tracheal stenosis, 6 patients had tracheal invasion by thryroid cancer and 1 patient had tracheal cancer. We analyzed the direct causes of tracheal stenosis, preoperative vocal cord function, operation technique, early and delayed postoperative complications, and the outcome of end-to-end anastomois. Result Decannulation without significant aspiration was achieved in 16 cases($89.5\%$). A 27 year-old man could not be decannulated because of restenosis. A 62 year-old woman could not be decannulated because of bilateral vocal cord palsy. Conclusion End-to-end anastomosis is a safe and effective surgical method for tracheal stenosis. Case selection for end-to-end anastomosis and preservation of recurrent laryngeal nerve during operation is very important.

• Journal of Yeungnam Medical Science
• /
• v.3 no.1
• /
• pp.237-241
• /
• 1986

In clinical microsurgery, limitation of space often prohibits rotation of a double clamp in an end-to-end anastomosis, or shortage of length of the secondary vessel in an end-to-side anastomosis does not allow visualization of the back wall. In these situation, back wall repair is extremely difficult. To overcome this problem, we use continuous suture technique without rotation of double clamp for end-to-end and end-to-side anastomosis of the 40 rat femoral arteries. After continuous sutures for microarterial anastomosis, the following results were obtained: Continuous sutures are useful in anastomosis where there is unavoidable limited access to the posterior wall and for some of the larger vessels now being anastomosed in free flap and other reconstructive surgery.

• Proceedings of the KSME Conference
• /
• 2001.11a
• /
• pp.442-447
• /
• 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%.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.37 no.4
• /
• pp.312-320
• /
• 2011

A reconstruction following a resection of malignant oral cavity tumors is one of the most difficult problems in recent oral oncology. For a better understanding of oral and maxillofacial reconstructive procedures, basic and advanced microvascular anastomosis techniques must be learned and memorized. The aim of this article was to clarify and define the microvascular anastomosis methods, such as primary closure after an arteriotomy, end to side anastomosis, end to end anastomosis, and side to side anastomosis with an artery and vein. This review article discusses the basic skills regarding microvascular anastomoses with brief schematic diagrams in the Korean language. This article is expected to be helpful, particularly to young doctors in the course of the Korean national board curriculum periods for oral and maxillofacial surgery.

• Korean Journal of Bronchoesophagology
• /
• v.7 no.1
• /
• pp.9-13
• /
• 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.

• Korean Journal of Bronchoesophagology
• /
• v.4 no.1
• /
• pp.27-34
• /
• 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.

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

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.27 no.1
• /
• pp.34-41
• /
• 2003

Finite element analysis of end-to-end artery/PTFE anastomosis recently have been researched. But, these studies were carried out without the compensation for the error of finite element analysis and assumed the artery and PTFE as the simple cylindrical shape in spite of being the fatty tissue which covers the heart. Therefore, we performed the convergency study with respect to increasing the element numbers and considered the fatty tissue as the elastic foundation in the finite element analysis. The results are as fallow ： 1. An anastomosis with the thinner thickness and larger diameter PTFE than artery could reduce the compliance disagreement. 2. A fatty tissue was affected to reduce the compliance mismatch in the vicinity of anastomosis of different material. Therefore a hypercompliant zone become narrorw and a compliance discrepancy decrease between the artery and the PTFE about 70%. And radial displacement with respect to longitudinal direction of an artery and the PTFE anastomosis was similar to a sectional compliance.

• Journal of Biomedical Engineering Research
• /
• v.13 no.4
• /
• pp.313-322
• /
• 1992

A finite analytic(FA) numerical study was performed to determin'e flow dynamics in the vicinity of an end-to-end anastomosis. Experimental data of instantaneous lumen cross-section were used to simulate steady flow through an end-to-end anastomosis In order to solve the governing axisymmetric Wavier-Stokes equations. Wall shear stresses increased proximal to the anastomosis In flow from the Penrose tubing to the PTFE graft. In flow the PTFE graft to the Penrose tubing, low wall shear stresses were observed distal to the anastomosis. The present study suggests a correlation betweerl regions of low wall shear stress and the do velopment of pnastomotic neointimal fibrous hyperplasia(ANFH ) in end-to-end anastomoses.