• Archives of Reconstructive Microsurgery
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• v.14 no.1
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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.

• The korean journal of orthodontics
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• v.22 no.1
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• pp.179-203
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• 1992

This study was designed to analyze nasal respiratory patency and its correlation with skeletal components in growing children with anterior crossbite. The subjects consisted of 40 control patients, 24 nose breathers with anterior crossbite and 18 mouth breathers with anterior crossbite. The mean age was 11.4 years in the control group, 10.1 years in nose breathing group and 9.5 years in mouth breathing group. The results were as follows, 1. In anterior cross bite group, and nasal respiratory airflow rates (N.R.A.R.) was significantly lower than that of control group regardless of nasal decongestants application. 2. The N.R.A.R. of mouth breathers with anterior crossbite in male group was significantly lower than that of mouth breathers, but increased to the level of control group after nasal decongestants application. But in female group, the N.R.A.R. was significantly lower in mouth breathing group at both conditions. 3. Mouth breathing group showed smaller anterior vertical nasal cavity height (ANS-ANS'), lower upper anterior facial height ratios (N-sp'/N-Me) and higher maxillary occlusal plane ratios (OL-ML/ML-NL) than those of nose breathing group with anterior crossibte. 4. Items showing nasal height (ANS-ANS', PNS-PNS'), anterior upper facial height (N-sp') was were strongly correlated with N.R.A.R. at 150 pascal in inspiration. But item showing maxillary occlusal plane ratios (OL-ML/ML-NS) was negatively correlated with N.R.A.R. at 150 pascal in inspiration. 5. There were forward tongue position in mouth breathing group, but it was not significantly correlated with N.R.A.R. at 150 pascal in inspiration.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.478-481
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• 1997

A technique or the preparation of porous polyurethane vascular prostheses was investigated. Small-diameter vessels are not in general clinical use due to their limited long-term biocompatibility and low patency rates in experimental trial. These limits are mainly due to the failure of mechanical unction of the vascular grafts. This failure has been suggested to result partially from compliance mismatch. The long-term patency is considered to depend critically on the properties of the material and the fabrication process of the graft. So the control of pores is very important and main points to develop a available vascular grafts. Two-kind polymer sheets was compared. One was the porous PU-sheet made at room temperature by the solvent/non-solvent exchange. And the other was the porous PU-sheet which was fabricated by thermal phase transition and solvent-/non-solvent exchange using the thermal controller. The polymer sheets had a uniform pore size and pore occupation. According to the result of the above experiments, polyurethane solution was injected into a mold designed or U-type tube. The average pore size and pore occupation were easily changed by changing polyurethane concentration, freezing temperature, and methods. This technique can give a proper pore size ($10{\sim}45\;{\mu}m$) or tissue in growth, and suitable compliances or matching with arteries and veins. Besides, the fabrication of more complicated shaped vessels such as the U-type vascular grafts is easily controlled by using the fixed mold. this method might give a desired compliant graft or artificial implantation with the presently valid medical polymers.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.297-305
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• 1979

Occlusive coronary artery disease presents a potential threat to a significant population in the United States. According to many case reports, the increasing incidence of coronary artery disease due to atherosclerosis is noted in Korean, recently. Operative vascular procedures have increased steadily in number over the past 20 years in the United States. There have been many isolated case reports about coronary artery surgery, but these had little clinical impact. Nowadays, major three coronary bypass surgery has developed principally at three cardiac centers in the United States since 1967. Among three coronary bypass operation, the aorta-coronary artery saphenous vein bypass graft was first demonstrated by Favolaro and Effler at the Cleveland Clinic in 1967. We experienced one case of coronary artery disease, which was treated successfully by aorta-coronary saphenous vein graft with mild hypothermia under extracorporeal circulation in May, 1977. Saphenous vein was removed from above the knee and was 2.5 mm in diameter. The left ventricle was not vented for the left ventricle was not overdistended. Temporary artificial pace-maker-Medtronic-was implanted for the prevention and treatment of post-operative arrhythmia and heart block in post-operative first day. He is a 57 year old male businessman who had been suffered from hypertension [200 mmHg in systolic pressure] since 4 years ago, who had intermittent conservative treatment at local clinic. He had been afflicted with severe chest pain with choking sensation for 50 days. This symptom was aggravated exposing cold weather, or cold water, but was respond to rest. Pre-operative ECG revealed no any other ischemic sign except sinus bradycardia. Significant S-T segment depression was noted at lead II, AVF after double 5 minutes exercise, indicating positive Master`s test. Serum cholesterol was slight elevated to 253 mg/dl. Final pre-operative diagnosis was made by coronary arteriogram, which showed about 1.0-cm segmental 90 % occlusive atherosclerotic lesion in the proximal part of right coronary artery above the origin of acute marginal artery. Left coronary artery revealed good patency and there was no collateral circulation between right and left coronary artery .Hospital course was not eventful. He was discharged with good result on the post-operative day. He has been free from chest pain for longer than 2 years. And also the arterial flow in the coronary bypass graft is auscultated with the pocket-sized ultrasonic velocity detector, which shows the patency of the coronary bypass graft good.

• Journal of Chest Surgery
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• v.53 no.1
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• pp.28-33
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• 2020

Background: When an arteriovenous fistula (AVF) is created using the basilic or deep cephalic vein, it is additionally necessary to transfer the vessels to a position where needling is easy; however, many patients develop wound-related postsurgical complications due to the long surgical wounds resulting from conventional superficialization of a deep AVF or basilic vein transposition. Thus, to address this problem, we performed videoscopic surgery with small surgical incisions. Methods: Data from 16 patients who underwent additional videoscopic radiocephalic superficialization, brachiocephalic superficialization, and brachiobasilic transposition after AVF formation at our institution in 2018 were retrospectively reviewed. Results: Needling was successful in all patients. No wound-related complications occurred. The mean vessel size and blood flow of the AVF just before the first needling were 0.73±0.16 mm and 1,516.25±791.26 mL/min, respectively. The mean vessel depth after surgery was 0.26±0.10 cm. Percutaneous angioplasty was additionally performed in 25% of the patients. Primary patency was observed in 100% of patients during the follow-up period (262.44±73.49 days). Conclusion: Videoscopic surgery for AVF dramatically reduced the incidence of postoperative complications without interrupting patency; moreover, such procedures may increase the use of native vessels for vascular access. In addition, dissection using a videoscope compared to blind dissection using only a skip incision dramatically increased the success rate of displacement by reducing damage to the dissected vessels.

• 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.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.123-126
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• 2002

Pollutants that are persistent, bioaccurnulative, and toxic have been linked to numerous adverse effects in human and animals, PBTs include heavy metals, polychlorinated biphenyls (PCBs), dioxins, polycyclic aromatic compounds (PACs) in addition to pesticides. This study focuses on toxic effects of the PBTs except pesticides on insects. Eight PBTs were selected from subgroups: three heavy metals (Pb, Hg, and Cd), two PCB mixtures (Aroclor mixtures 1 and 2), 2,3,7,8-tetrachlorodibenzo-p-dioxin, two monophenols (4-octylphenol and 4-nonylphenol), and tetrabutyltin, Beet armyworm, Spodoptera exigua, was used as test target insect species. Three physiological markers (metamorphosis, immune reaction, and follicle patency) were assessed in each exposure to different doses of the PCBs. Heat-shock proteins as molecular markers were also analyzed in response to the PCBs. All tested PBTs were toxic to metamorphosis from larvae to pupae when they were applied with diet. Two PCB mixtures were the most toxic compounds in this assay by giving significant toxicity at 0.005 ppm, while others had from 10 to 1000 ppm. Dioxin (0.1 ppb), tetrabutyltin (0.1 ppb), Pb (10 ppb), and Hg (0,01 ppb) were potent to inhibit immune reactions analyzed by inducing phenoloxidase activity and blocked phospholipase $A_2$ enzyme, Tetrabutyltin and dioxin significantly induced follicle cell patency, but their effects were lower than that of endogenous juvenile hormone, Dioxin, Pb, Hg, and Cd could induce the expression of heat shock proteins that were detected by immunoblotting against human HSP70 monoclonal antibody. HSP78 and HSP80 were upregulated in response to the PBTs. This expression was detected from the fat body and epidermis at as fast as 4h after injection. All these results clearly suggest that PBTs give significant ecotoxicity to insects that are valuable organisms in our environment.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.559-564
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• 2010

The purpose of this study was to evaluate the value of dacryoscintigraphy with Tc-99 m Pertechnetate, which is useful in functional nasolacrimal duct obstruction diagnosis in human medical science, by applying it to normal dogs. Dacryoscintigraphy was performed on six clinically healthy beagle dogs to confirm normal passage of their lacrimal ducts. The scintigraphic images of both lacrimal system were obtained at 5 min, 10 min, and 20 min after Tc-99 m Pertechnetate administration, respectively. If lacrimal duct does not come into view within 20 min, delayed images at 30min, 45min and 60 min were gained. After drawing ROI of left and right canaliculus, lacrimal sac, and nasolacrimal duct acquired after dacryoscintigraphy, we measured each counting rate and developed a counting rate table for each time interval. Of the total of 12 places, 10 (83.3%) showed patency within 20 min, and 11 (91.6%) showed patency within 30 min. In one dog, a functional obstruction of right lacrimal canal was observed. Dacryoscintigraphy could provide useful information about functional and anatomical lacrimal duct obstruction in veterinary medicine as well as in clinical research.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.1_2
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• pp.77-88
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• 1992

Recently, diabetic patients are increasing in the field of microvascular surgery. Diabetes melltius is known to be related to arterial damage, platelet malfunction and thrombus formation. After microvascular anastomosis, delayed repair and vascular occlusion occurred more frequently in diabetic state. This study was performed to investigate the patency rate and process of endothelial healing after microvascular anastomosis of femoral artery in diabetic rat by scanning electron microscope. The animals were divided into two groups, 20 diabetic-induced and 20 non-diabetic groups. Diabetes was induced with a injection of Streptozotocin(50mg/kg b.w., Sigma Chemical Co.) to tail vein. The results obtained were as follows: 1. Macroscopically, anastomotic site was intact except a few cases showed minimal inflammatory sign around the wound site. But the inflammatory change was frequently occurred in diabetic-induced group. 2. The patency rate was 95% (19/20) in non-diabetic group and 65% (13/20) in diabetic-induced group. 3. In the non-diabetic group, anstomotic region was mostly endothelized by the alignment along the long axis of vessel but stitchs were not covered with endothelial cells. The thichkening of vessel wall was not observed. 4. In the diabetic-induced group, anastomotic region was not endothelized but covered with blood cellular components and connective tissue instead of endothelial cells. The thickening of the vessel wall was prominent in some diabetic-induced rats. These results suggest that diabetes was related to delayed regeneration of endothelium of vessels after microsurgical anastomosis.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.19-26
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• 2017

Objectives: Recently, bioceramic sealers like EndoSequence BC Sealer (BC Sealer) have been introduced and are being used in endodontic practice. However, this sealer has limited research related to its retreatability. Hence, the aim of this study was to evaluate the retreatability of two sealers, BC Sealer as compared with AH Plus using micro-computed tomographic (micro-CT) analysis. Materials and Methods: Fifty-six extracted human maxillary incisors were instrumented and randomly divided into 4 groups of 14 teeth: 1A, gutta-percha, AH Plus retreated with chloroform; 1B, gutta-percha, AH Plus retreated without chloroform; 2A, gutta-percha, EndoSequence BC Sealer retreated with chloroform; 2B, gutta-percha, EndoSequence BC Sealer retreated without chloroform. Micro-CT scans were taken before and after obturation and retreatment and analyzed for the volume of residual material. The specimens were longitudinally sectioned and digitized images were taken with the dental operating microscope. Data was analyzed using an ANOVA and a post-hoc Tukey test. Fisher exact tests were performed to analyze the ability to regain patency. Results: There was significantly less residual root canal filling material in the AH Plus groups retreated with chloroform as compared to the others. The BC Sealer samples retreated with chloroform had better results than those retreated without chloroform. Furthermore, patency could be re-established in only 14% of teeth in the BC Sealer without chloroform group. Conclusion: The results of this study demonstrate that the BC Sealer group had significantly more residual filling material than the AH Plus group regardless of whether or not both sealers were retreated with chloroform.