• 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.

• Archives of Reconstructive Microsurgery
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• v.25 no.1
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• pp.12-14
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• 2016

In cases of replantation, accurate closure of all structures, including bone, tendons, arteries, nerves, and veins is essential. Among these, the vein is a weaker structure and is damaged severely in most amputation cases. After fixation of bone, repair of tendons, nerves, and arteries, surgeons often experience difficulty in performing venous anastomoses. We found that in such cases, venous anastomosis is easy to perform using an additional incision after closure of the original wound. In a 33-year-old male patient with amputation of all four fingers at the metacarpophalangeal joint level, venous anastomoses were performed with dorsal veins using additional incisions after completion of the fixation of bones and repair of all other structures and closure of the skin due to surgical site tension.

• Advances in pediatric surgery
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• v.6 no.1
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• pp.40-44
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• 2000

Congenital esophageal stenosis (CES) is a narrowing of the esophageal lumen from birth. Three types of CES have been described; tracheobronchial remnants (TBR), membranous web (MW), and fibromuscular stenosis (FMS). We reviewed the clinical features and the surgical outcome of 14 patients, pathologically confirmed as CES. Nine patients had TBR, 3 FMS, and 2 MVV. The mean age at operation was 3.8 years. Five patients were boys and 9 girls. Four patients had other congenital anomalies. Segmental resection of the lesion and end to end anastomosis was utilized in all cases except one who underwent myotomy. The stenotic segment was located at the distal esophagus in all patients. There were 8 complications in 6 patients, but no mortality. The mean follow-up period was 68 months. There were no feeding problems but 3 patients had minor gastroesophageal reflux. Our result indicates that segmental resection and anastomosis is a satisfactory surgical procedure in the management of CES.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.4
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• pp.232-238
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• 2003

This study was performed to evaluate the effect of topical and intravenous heparin on thrombosis and patency in the microvascular anastomosis of the traumatized veins. Nine white rabbits weighing about 2 kg were used. After exposure of both femoral veins, the veins were crushed by the jaws of smooth needle holder in order to create a thrombosis model. Transectional incision was made in the vein. The animals were then divided into 3 groups based on the administration method of heparin: 1) Experimental Group I, topical irrigation of lumen with heparin saline solution (n=6); 2) Experimental Group 2, topical irrigation of lumen with heparin saline solution and intravenous injection of heparin (0.75 mg/kg) via the marginal ear vein for 3 days; 3) Control Group, topical irrigation of lumen with saline solution (n=6). The patency was evaluated with empty-and-refill test and thrombus formation was judged by surgical microscope. The results were as follows: 1. Thirty minutes after microvascular anastomosis, the patency of all Experimental Groups was better than Control group. However, there was no significant difference among groups. 2. Three days after anastomosis, the patency of all Experimental Groups was much more improved than that of Control Group (P<0.05). There was no significant difference between Experimental Group 1 and 2. 3. Three days after anastomosis, the amount of thrombus in all Experimental Groups was much less than that of Control Group (P<0.05). 4. In histologic findings a lot of luminal thrombus were observed around sutured area in Control Groups. Few luminal thrombus was observed in all Experimental Groups. Mild necrosis in the vessel wall was observed around sutured area in all specimens. These results indicate that topical irrigation of heparin may improve the patency and inhibit the formation thrombus in the microvascular anastomosis of the traumatized veins.

• Journal of Veterinary Clinics
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• v.23 no.1
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• pp.61-64
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• 2006

A 4.65 kg 13-month-old male Pekingese dog was referred to veterinary teaching hospital of Konkuk University for evaluation of dysuria. On physical examination, severe distention of urinary bladder was found in abdominal palpation. Urinary catheter could not be guided into urinary bladder. On serum biochemistry, blood urea nitrogen (35.6 mg/dl) and creatinine (1.9 mg/dl) were increased. Obstruction part of proximal membranous urethra was founded on urethrogram. The length (13 mm) of obstruction part was callipered by cystourethrogram and urethrogram on operation. Surgical resection of obstruction part of urethra was performed without pubic osteotomy, and anastomosis was performed with 5-0 polyglycolic acid. Omentum was placed around the urethral anastomosis. On first day after surgery, appetite was good. On day 5, complete blood count and serum biochemistry showed normal range but mild urinary incontinence was showed after removing catheter. On day 7, urinalysis showed normal condition. On day 14, no leakage of surgical site was observed in excretory urogram. On day 21, no more urinary incontinence and good micturition were found. On 1 year later, the patient showed healthy condition without recurrence.

• 대한미세수술학회:학술대회논문집
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• 1996.10a
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• pp.157.2-158
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• 1996

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.131-132
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• 2021

• Journal of Chest Surgery
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• v.21 no.5
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• pp.842-849
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• 1988

Between July, 1987, and September, 1988, 6 patients with coronary occlusive disease received coronary artery bypass surgery at Kyungpook University Hospital. There were five males and one female whose age ranged from 39 to 64 years[mean 54*8.0 years]. Of the 6 patients, 5 suffered from unstable angina, 1 suffered from stable angina. Selective coronary angiography revealed a significant stenosis of the left anterior descending artery in 6 cases, of its diagonal branch in 1 case, of the right coronary artery in 1 case, the circumflex artery in 1 case, and of its obtuse marginal branch in 1 case. The mode of anastomosis were single saphenous vein graft in 3 cases, single left internal mammary artery graft in 1 case, double saphenous vein graft with sequential anastomosis in 1 case, and left internal mammary artery plus saphenous vein graft in 1 case. Of these, 6 grafts to left anterior descending artery were done. There was no operative death, but perioperative myocardial infarction was happened in 1 case. All survivors were free of angina and discontinuing medical therapy during the follow up period[mean 7.8*5.15 months].

• Advances in pediatric surgery
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• v.19 no.1
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• pp.32-38
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• 2013

The purpose of this study is to analyze the early experience of the laparoscopic adhesiolysis for the intestinal obstruction due to postoperative adhesion. Seven patients were included in this study. The median age of those patients was 13, and there were 3 males and 4 females. Previous diagnosis and surgical procedure were various in seven cases, including small bowel resection with tapering enteroplasty, Boix-Ochoa fundoplication, Ladd's procedure with appendectomy, mesenteric tumor resection with small bowel anastomosis, ileocecal resection and anastomosis, primary gastric repair, and both high ligation. A successful laparoscopic adhesiolysis was performed in one who had high ligation for inguinal hernia and had a single band adhesion. Six out of 7 (86%) cases needed to convert open surgery due to multiple and dense type of adhesion. In conclusion, laparoscopic approach with postoperative small bowel adhesion seems safe. However, it might be prudently considered because of high rates of conversion in children.

• Archives of Reconstructive Microsurgery
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• v.8 no.1
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• pp.22-27
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• 1999

While the conventional end-to-end anastomotic technique is accepted as 'the golden standard' for microvascular anastomosis, it is time-consuming and tedious. In an effort to offer faster and safer ways of performing microvascular anastomoses, numerous anastomotic techniques have been proposed, but further refinements in microvascular techniques are still necessary. A 'continuous suture with interrupted knot' technique was devised for faster and safer anastomosis. It has been successfully used in microanastomoses of both artery and vein for free tissue transfer. It is a combination of the interrupted suturing technique and the continuous suturing technique. First, a continuous suture is made with the size of loop decreasing in order, and then the sutures are tied individually from the first loop to the last one as in the conventional interrupted suturing technique. It was applied clinically to fourteen patients over the past ten months and found to be a highly efficient technique that satisfied our needs. This 'continuous suture with interrupted knot' technique has several advantages over other techniques : The operative time is reduced comparing conventional interrupted suture technique. By delaying the tie and with the vessel walls kept separated, the risk of through-stitch can be reduced. Tying all the sutures at one time not only speed up the procedures, but also reduced the surgeon's fatigue. In addition, it has no problem of anastomotic stenosis which is a disadvantage of continuous suture technique. This technique proved to be faster and safer, and has patency equal to that of the conventional end-to-end anastomosis. It is of great help to the surgeon in reducing operative time, especially in clinical situations when many anastomoses are required, or lengthy grafting procedures are undertaken.