• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권4호
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• pp.312-320
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• 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.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권4호
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• pp.300-305
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• 2005

Purpose: For the reconstruction of maxillofacial defect created by trauma, infection, or tumor etc, the role of microvascular anastomosis or vessel graft has been increased. Many methods has been tried to increase the success rate of microvascular anastomosis. Various anticoagulants and thrombolytic agents have been used to reduce the failure rate of microvascular anastomosis and avoid re-operation. Many drugs, however, have been used in the limited cases because most of these drugs may cause complications, such as allergy, fever or systemic bleeding. This study was performed to evaluate the influence of the Argatroban on patency and thrombosis in microvascular anastomosis when it is used for local irrigation or general administration. Materials & methods: Eight mature rabbits, weighing 2kg, were used. After exposing both femoral veins, the artificial thrombotic model was made by crushing injury using a smooth needle holder, and the transverse incision were made on femoral vein. The animals were divided into 4 groups according to Argatroban administration methods; control group (n=4), topical irrigation of lumen with saline solution; experimental group 1 (n=4), topical irrigation of lumen with Argatroban saline solution; experimental group 2 (n=4), topical irrigation of lumen with heparin followed by intravenous injection of Argatroban; experimental group 3 (n=4), topical irrigation of lumen with Argatroban followed by IV of Argatroban. Microvascular anastomosis was done with 10-0 Ethilon. The patency was evaluated by empty-and-refill test 30 minutes and 3 days after microanastomosis. The thrombus formation was examined 3 days after microanastomosis by surgical microscope. The histologic findings were also examined. Results: 1. Thirty minutes after microvascular anastomosis, the patency of all experimental groups was better than that of control group, but there was no significant difference among groups. 2. Three days after microvascular anastomosis, the patency of all experimental groups was more improved than that of control group (p<0.05). There was no significant difference among experimental groups. 3. Three days after microvascular anastomosis, the amount of thrombus in all experimental groups was less than that of control group (p<0.05). There was no significant difference among experimental groups. 4. Histologically, a lot of luminal thrombus was observed around sutured area in control group. Few luminal thrombus was observed in all experimental groups. The necrotic changes were observed on the sutured vein wall in all specimens. Conclusion: These results indicate that topical irrigation and/or intravenous administration of Argatroban is effective in improving patency and preventing thrombus formation after microvascular anastomosis.

• Archives of Plastic Surgery
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• 제40권3호
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• pp.214-219
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• 2013

Background We established the Microvascular Research Center Training Program (MRCP) to help trainee surgeons acquire and develop microsurgical skills. Medical students were recruited to undergo the MRCP to assess the effectiveness of the MRCP for trainee surgeons. Methods Twenty-two medical students with no prior microsurgical experience, who completed the course from 2005 to 2012, were included. The MRCP comprises 5 stages of training, each with specific passing requirements. Stages 1 and 2 involve anastomosing silicone tubes and blood vessels of chicken carcasses, respectively, within 20 minutes. Stage 3 involves anastomosing the femoral artery and vein of live rats with a 1-day patency rate of >80%. Stage 4 requires replantation of free superficial inferior epigastric artery flaps in rats with a 7-day success rate of >80%. Stage 5 involves successful completion of one case of rat replantation/transplantation. We calculated the passing rate for each stage and recorded the number of anastomoses required to pass stages 3 and 4. Results The passing rates were 100% (22/22) for stages 1 and 2, 86.4% (19/22) for stage 3, 59.1% (13/22) for stage 4, and 55.0% (11/20) for stage 5. The number of anastomoses performed was $17.2{\pm}12.2$ in stage 3 and $11.3{\pm}8.1$ in stage 4. Conclusions Majority of the medical students who undertook the MRCP acquired basic microsurgical skills. Thus, we conclude that the MRCP is an effective microsurgery training program for trainee surgeons.

• 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.

• Archives of Plastic Surgery
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• 제35권2호
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• pp.159-164
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• 2008

Purpose: Microvascular free tissue transfer has become a reliable technique for the reconstruction of complex wounds. Occasionally, unexpected intraoperative thrombosis and/or spasm of recipient artery might be annoying problems even for the technically competent microvascular surgeons. If such problems are not treated properly, they will inevitably cause to flap failure. Methods: From January 2006 to February 2007, soft tissue reconstructions by free tissue transfers were performed on 21 patients having complex defects in the lower extremity. Although segmental revision and various pharmacologic agents were repeatedly applied, arterial occlusions were not managed in 6 cases. For removal of thrombi and release of spasm, Fogarty No. 2 or No. 3 catheters were inserted into the lumen to the proximal recipient artery. Its balloon was then inflated after passing through a resistant area. Next, the catheter was gently withdrawn backward. Results: After the Fogarty catheter was inserted two or three times, the pulsatile arterial flow was restored. When the catheter was inserted into the lumen, a feeling of resistance existed in a 5-10cm more proximal portion that could not be easily accessed from the vascular end. After the reestablishment of blood flow, successful anastomoses were achieved and immediate rethrombosis or spasm did not occur. No long-term sequelae associated with balloon trauma to the arterial wall were observed. Conclusion: The use of the Fogarty catheter can be an effective method in treating pedicle thrombosis and spasm. This is a very simple and rapid technique that offers microvascular surgeons another option to increase the success rate of microvascular anastomosis in free tissue transfers.

• 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.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권1호
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• pp.16-29
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• 1991

미세혈관봉합술에서의 가장 큰 문제점은 봉합부에서의 내피손상과 혈전형성이라고 볼 수 있다. 이 연구의 목적은 봉합시 일어날 수 있는 내피손상부에서의 치유과정을 관찰코져 각각 다른 문합술인 혈관함입문합술과 혈관단단문합술을 백서 대퇴부동맥에 적용하여 개존율및 전자현미경적 관찰을 통하여 비교하였고 아울러 임상에의 적용 가능성을 검토코져 하였다. 저자는 미세현미경시야에서 혈관함입문합술 20례와 단단문합술 20례를 시행한후 1일, 3일, 1주, 2주, 3주에 각각 4마리씩 희생후 문합혈관부를 육안관찰후 주사전자현미경으로 조직변화를 관찰하여 다음의 결과를 얻었다. 1. 혈관 함입문합술 시술시 문합후 개존율은 90%였고 혈관 단단문합술은 85%였다. 2. 혈관 함입문합시 술후 3일째는 문합부에서의 혈소판 응집물이 기질화되었으며 함입으로 좁아져 있던 혈관내경이 약 1주째 혈관 합입부의 중막 위축현상으로 다소 넓어졌다. 3. 혈관 내피재생과정을 혈관 함입문합술에서는 7일에서 14일경에, 혈관 단단문합술에서는 14일에서 21일째 완성되었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권2호
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• pp.132-140
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• 2007

This study compared the histological patency rates of anastomoses of the femoral artery. Twelve rabbits weighing about 2 kg were studied. Both the right and left femoral arteries were cut. The control group had no damage to the vessel, saline irrigation, and micro-anastomosis. Experimental group I had a crush injury to the vessel, saline irrigation, and micro-anastomosis. Experimental group II had a crush injury, saline irrigation, 100 U/ml heparin irrigation, and micro-anastomosis. Experimental group III had the same treatment as experimental group II plus the systemic application of 100 U/kg heparin iv. The histological patency rates were compared. The patency rates of the control group 30 min and 3 days after the anastomosis were 100 and 83%, respectively. The respective rates for experimental groups I and II 30 min and 3 days after the anastomosis were 100% in all cases. The respective rates in experimental group III were 100 and 83%. In this study, no significant correlation was observed between the patency rate and the effects of local irrigation or the systemic application of heparin on the microvascular anastomosis of the rabbit femoral artery. However, the patency rate tended to decrease concomitantly with an increase in surgery time. Increased bleeding was observed after the systemic application of heparin. Obvious damage to the crush-injured vascular endothelium was detected on histologic examination of the micro-anastomosed area. In addition, some vessels subjected to crush injury contained thrombi attached to the vascular endothelium. No preventive effect of heparin on thrombus formation was observed.

• 대한두개안면성형외과학회지
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• 제21권1호
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• pp.27-34
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• 2020

Background: Free-flap reconstruction for recurrent head and neck cancer may be challenging depending on the previous treatments, those are, chemotherapy, radiotherapy, and surgery, including neck dissection or free tissue transfer. Specifically, the previous treatment could compromise the neck vessels, thereby making free-flap reconstruction more difficult. This study aimed to investigate the correlation between previous treatments and vascular compromise of the free flap. Methods: In this retrospective study, 124 free-flap reconstructions in 116 patients for recurrent head and neck cancer between 1993 and 2017 were investigated. The demographic characteristics, previous treatments, flap choices, infections, recipient vessels, and vascular crises were evaluated. Results: Of the 124 reconstruction cases, 10 had vascular crises. There were six revisions, totaling six flap failures. The success rate of free-flap reconstruction for recurrent cancer was 95.2%, which significantly differed from that for primary cancer (98.8%, p= 0.006). Moreover, in the recurrent cancer group, no correlation was found between previous treatments and vascular crises (p> 0.05). Increased rates of contralateral or uncommon anastomoses were found following neck dissection (p< 0.05). Conclusion: Previous neck dissection or radiotherapy could lead to scarring and tissue damage, which could in turn make microvascular reconstruction more challenging; however, the effect was not definite in this study. Approximately 60% of patients with previous neck dissection had compromised ipsilateral recipient vessels, which resulted in contralateral or uncommon anastomoses. In this study, free-flap reconstruction seems to be quite safe and preferable in patients with recurrent head and neck cancer based on the overall survival rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권4호
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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.