• 대한의용생체공학회:의공학회지
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• 제13권4호
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• pp.339-352
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• 1992

A numerical simulation of the steady and pulsatile flow across the end-to-side anastomosis was performed In order to understand the role of flow dynamics in the preferential bevel opment of distal anastomotic intimal hyperplasla. The finite element technique was employed to solve two-dimensional unsteady pulsatile flow in that region. The results of the steady flow revealed that low shear stresses occur at the proximally occluded host artery and at the recirculation region in the Inner wall just distal to the toe region of the anastomosis. The nor- mal;zed wall shear rate was increased, as was the recirculation zone size in the host artery of the by-pass graft anastomosis, with increased anastomotic junction angle. In order to min imize the size of the low wall shear region which might result in the intimal hyperplasia in the by-pass graft anastomosis, a smaller anastomotic junction angle is recommended. The pulsatile flow simulation revealed flow that regions of low and ascillating mali shear do exist near the anastomosis as In the steady simulation. The shift of stagnation point depends on the pulsation of the flow. As the flow was accelerated at systole, the stagnation point moved downstream, disappered at early diastole and reappeared during late diastole. Low shear stress was also found along both walls of the occluded proximal artery. However, the diastolic flow behavior is quite different from the steady results. The vortex near the occluded artery moved downstream and inwardly during late systole, and disappeared during diastole. Recirculations proximal to the toe and heel regions were significant during diastole. Shear stress oscillation was found along the opposite wall. The results of the present study revealed that tow shear occurs at the proximally occluded host artery aud the recirculation region in the inner wall Just dlstal to the toe region of the anastomosis. The present study suggested that the regions of fluctuated wall shear stress wit flow separation is correlated with the preferential developing regions of anastomosis neointial fibrous hyperplasia.

• Archives of Plastic Surgery
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• 제47권3호
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• pp.242-249
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• 2020

Background The Exoscope is a novel high-definition digital camera system. There is limited evidence signifying the use of exoscopic devices in microsurgery. This trial objectively assesses the effects of the use of the Exoscope as an alternative to the standard operating microscope (OM) on the performance of experts in a simulated microvascular anastomosis. Methods Modus V Exoscope and OM were used by expert microsurgeons to perform standardized tasks. Hand-motion analyzer measured the total pathlength (TP), total movements (TM), total time (TT), and quality of end-product anastomosis. A clinical margin of TT was performed to prove non-inferiority. An expert performed consecutive microvascular anastomoses to provide the exoscopic learning curve until reached plateau in TT. Results Ten micro sutures and 10 anastomoses were performed. Analysis demonstrated statistically significant differences in performing micro sutures for TP, TM, and TT. There was statistical significance in TM and TT, however, marginal non-significant difference in TP regarding microvascular anastomoses performance. The intimal suture line analysis demonstrated no statistically significant differences. Non-inferiority results based on clinical inferiority margin (Δ) of TT=10 minutes demonstrated an absolute difference of 0.07 minutes between OM and Exoscope cohorts. A 51%, 58%, and 46% improvement or reduction was achieved in TT, TM, TP, respectively, during the exoscopic microvascular anastomosis learning curve. Conclusions This study demonstrated that experts' Exoscope anastomoses appear non-inferior to the OM anastomoses. Exoscopic microvascular anastomosis was more time consuming but end-product (patency) in not clinically inferior. Experts' "warm-up" learning curve is steep but swift and may prove to reach clinical equality.

• 한국임상수의학회지
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• 제18권2호
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• pp.124-132
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• 2001

The purpose of this study is to know whether single layer continuous connell suture is an acceptable alternative to simple interrupted approximating suture for end-to-end intestinal anastomosis in dogs. Fourteen mixed-breed dogs weighing 2 to 5 kg were allotted to group treated with simple interrupted approximating suture (Group I) and group treated with single layer continuous Connell suture (Group II), each of 7 dogs. All dogs in each suture pattern were compared with time for total operation ad suture elapsed for intestines to anastomose, clinical signs, changing of pre-and postoperative luminal size, status of feces, adhesion at anastomotic site for 14 days after operation. Time for total operation and suture time for intestinal anastomosis were none significant between Group I and Group II, although those in Group II was about 3 minutes shorter than those in Group I, respectively. Group I spent average 47.08${\pm}$11.10 minutes on total operation, 20.97${\pm}$5.54 minutes on suture time for intestinal anastomosis and Group II spent average 44.74${\pm}$7.77 minutes, 17.73${\pm}$3.05 minutes, respectively. All dogs were no special differences in vitality, vomiting, appetite between Group I and Group II for 14 days after operation. All dogs, except one dog in Group I, had showed normal vitality and appetite since 6~8 days after operation. Initial return of fecal passage showed in all dogs before 6 days after operation and thereafter most dogs showed normal feces. According to results, it was thought that all dogs with normal vitality and appetite before 8 days had showed good prognosis. There were no changes of intestinal luminal size in 2 dogs performed Group In and one dog performed Group II between at operation and 14 days after operation. Narrowing rate of intestinal lumen in Group I was average 9.3% of the normal diameter, whereas in Group II, 9.5% of normal diameter. In complications after operation, only one dog in Group I showed intestinal intussusception but the others didn't. Length of adhesion was measured between intestinal anastomotic site and omental graft. Length of adhesion in dogs performed Group II was mostly shorter than that of Group I. Adhesion with proximate intestines occurred in five dogs, which consisted of 3 dogs performed Group I and 2 dogs performed Group II. Concurrently, they had a great length of adhesion between anastomotic site and omental graft. There were no great differences between Group I and Group II about speed of operation, clinical signs, complications such as leakage and stricture. And all dogs performed intestinal anastomosis showed good clinical condition and prognosis. In conclusion, Single layer continuous Connell suture can safely perform an intestinal anastomosis and be an alternative of simple interrupted approximating suture in aspect of speed clinically.

• Archives of Reconstructive Microsurgery
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• 제13권2호
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• pp.101-106
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• 2004

Purpose : This study evaluated the effect of VEGF in the arterial anastomosis by using light and electron microscopy. Marerials and method : Rats underwent femoral arterial end-to-end anastomosis after transection and topical VEGF treatment. The proximal and distal segments of the femoral arteries was drenched with 1 drop of VEGF $(100ng/100{\mu}l/bottle)$. and when half of the repair was finished, the other 1 drop was drenched and then the repair was continued to complete the anastomosis. Gross and histologic characteristics of arterial wall were assessed after 3 days, 1, 3 and 5 weeks. In the control group, normal saline solution instead of VEGF was dropped with the same method in the anastomosis. Results : The histologic findings of the arterial wall were the vascular remodeling with the infiltration of inflammatory cells at early stages and the tissue fibrosis at lately stages in the anastomotic sites of the control and the VEGF-treated groups. The scanning electron microscopic results were; (1) the anastomotic sites were covered by many irregular cells with long cytoplasmic processes at the early stages. (2) After 1 week, endothelial cells started to cover the anastomotic sites. (3) After 3 weeks, the anastomotic sites were partially covered by endothelial cells in the control group. (4) After 5 weeks, the anastomotic sites were completely covered by endothelial cells in the control and VEGF-treated groups. (5) In the VEGF-treated group, the anastomotic site was completely covered by endothelial cells which directed parallel to longitudinal axis of arteries after 3 weeks. Conclusion : Topical VEGF maintained luminal integrity by decreasing fibrosis and increasing re-endothelialization. These findings suggest that topical VEGF may be a promising new strategy to enhance healing and improve the outcome of vascular anastomosis.

• Journal of Chest Surgery
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• 제34권10호
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• pp.733-744
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• 2001

배경: 대동맥 축착증과 심실중격결손이 동반된 환아의 적절한 치료 방침에 대해서는 이견이 많다. 본 연구는 생후 6개월 이하의 환아에서 대동맥 축착증과 심실중격결손의 일타 완전교정 결과 및 수술방법에 따른 대동맥 축착증의 재발에 대해 알아보고자 하였다. 대상 및 방법: 1995년 1월부터 2000년 12월가지 본원에서 대동맥 축착증과 심실중격결손으로 일차 완전교정을 시행받은 생후 6개월 이하의 환아 33명을 대상으로 후향적으로 조사하였다. 환아의 평균 연령과 체중은 각각 54$\pm$37일(12일~171일)과 3.9$\pm$1.1kg(1.5~6kg)이었다. 대동맥 축착 고정은 연구 초기에는 저체온하 완전순환정지하에서 시행하였으며 최근에는 순환정지없이 무명동맥을 통한 국소 뇌관류 상태에서 시행하였다. 축착증 교정 방법은 초기에는 Extended cad-to-end anastomosis(EEEA;n=16)와 Extended side-to-side anastomosis(ESSA;n=2)를, 최근에는 Extended end-to-sidc anasto mosis(EESA;n=15)를 이용하였다 심실중격결손은 초기 16명에서는 Dacron을, 최근 17명에서는 자가 심낭편을 이용하여 폐쇄하였다. 대동맥궁 발육부전은 29명(88%)에서 있었으며 원위부 발육부전 18명, 완전형 5명, 그리고 복잡형은 6명이었다.

• 대한기관식도과학회지
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• 제12권2호
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• pp.5-9
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• 2006

• Archives of Reconstructive Microsurgery
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• 제14권1호
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• pp.57-62
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• 2005

Microvascular anastomosis with suture technique is a basic skill but there are several problems such as stenosis, thrombosis and long operating time. Recently plastic surgeons have developed non-suturing mechanical coupling devices for microvascular anastomosis. The authors applied non-penetrating vascular clips (VCS clips) in the field of free flap surgery of head and neck area. Between August of 2004 and January of 2005, we performed 9 free flaps (16 vessels) using small-sized VCS clips. Four stay sutures were applied first and then VCS clips were placed between sutures about 1 mm apart. Vascular pedicle of free flap included the descending branch of lateral circumflex femoral vessel, thoracodorsal vessel, deep inferior epigastric vessel and cephalic vein. The recipient vessels were the superior thyroid artery, superficial temporal artery, internal jugular vein, external jugular vein, and superficial temporal vein. We performed 13 end-to-end (4 arteries and 9 veins) and 3 venous end-to-side anastomoses. No flap related complication occurred but we applied additional clips or sutures in two cases due to blood leakage after completion of anastomosis. Primary patency rates seemed to be good and more rapid anastomosis could be done than conventional suture technique. Advantages of VCS technique are high patency rate, low thrombogenecity and rapidity. Although the high cost of VCS instrument may be a problem, this clip could be applied safely in microvascular free tissue transfer.

• Journal of Gastric Cancer
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• 제23권4호
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• pp.523-534
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• 2023

Purpose: Intra-abdominal infection is a common postoperative complication of laparoscopic pylorus-preserving gastrectomies (PPGs). Many studies have reported that intra-abdominal infectious complications after gastrectomy adversely affect patient survival outcomes. To prevent gastric fluid leakage into the abdominal cavity, we developed a novel anastomosis method in which the stomach lumen is not opened (termed the non-opened clean end-to-end anastomosis method [NoCEAM]) and evaluated its feasibility. Materials and Methods: Subsequent to lymphadenectomy, the oral and anal resection lines were sutured using an intraoperative endoscope. After closing the stomach circumferentially with clips, the specimen was rolled outward like a "donut." We resected the specimen circumferentially using a linear stapler, and anastomosis was completed simultaneously. We examined the feasibility of this procedure ex vivo, using three porcine stomachs, and in vivo, using one pig. Subsequently, we applied the procedure to 13 consecutive patients with middle-third early gastric cancer utilizing laparotomic, laparoscopic, and robotic PPG. Results: NoCEAM was completed in all porcine models and human cases. In the human cases, the mean operation time (±standard deviation) was 279±51 minutes, and mean blood loss volume was 22±45 mL. The mean number of linear staples used was 5.06±0.76. None of the patients had complications, and all were discharged on the eighth postoperative. The serum total protein, serum albumin, and hemoglobin levels did not change significantly after surgery. Conclusions: NoCEAM is feasible and safe for performing totally laparoscopic or robotic PPG. It may reduce postoperative complications, such as intra-abdominal infections.

• Journal of Chest Surgery
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• 제17권3호
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• pp.448-455
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• 1984

Coarctation of the Aorta is a congenital constriction of aorta of varying degree, usually located at or near the aortic ismuth with frequent associations of other cardiac anomalies. Various modes of surgical corrections, such as resection and end-to-end anastomosis, graft interposition, angioplasty using prosthetic patch or subclavian flap have been used according to the status of coarctation and age of the patient. We have experienced two cases of surgically treated coarctation of the aorta, one of which was preductal coarctation with hypoplastic aortic arch and ventricular septal defect in a 4 year old boy, and the other case was juxtaductal type with aortic regurgitation. Subclavian flap angioplasty with additional pulmonary artery banding procedure was done in the first case and wedge resection with end-to-end anastomosis and aortic valve replacement [St. Jude valve, 23mm] 20 days later of first operation in the other case. The first case developed massive tarry stool on 3rd POD, probably due to mesenteric arteritis with resultant bowl ecrosis, and expired the next day. Recovery was uneventful with the second case.

• Journal of Chest Surgery
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• 제21권2호
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• pp.389-394
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• 1988

The patient was 22-year old male who had been suffered from labored breathing. Computerized tomography, tracheoscopy, tracheogram disclosed tracheal obstruction by external mass compression on Tl level, which ranged 4.Oem in the length and approximately 4mm in diameter on tracheogram. Under the local anesthesia, tracheostomy was done to prevent intraoperative airway obstruction. And general anesthesia, low collar incision 8z extended median sternotomy was made and nearly total thyroidectomy was performed. After the circumferential resection of the obstructed segment approximately 4cm in length[7 tracheal rings], direct end-to-end anastomosis of trachea was performed. Postoperatively, the patient`s neck was maintained in flexion state to reduce tension of anastomotic site. Postoperatively. medical therapy[Comthyroid k Calcium lactate] and radiotherapy were done. At present, 2-months after operation, he lives well.