• Journal of Korean Neurosurgical Society
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• v.65 no.6
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• pp.853-860
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• 2022

Objective : This prospective, randomized, double-blinded trial aimed to evaluate the efficacy and safety of prophylactic ramosetron administration against postoperative nausea and vomiting (PONV) in patients undergoing microvascular decompression (MVD). Methods : In this study, 100 patients undergoing MVD were randomly allocated to the control (normal saline, 2 mL) or ramosetron (ramosetron, 0.3 mg) groups at the end of surgery. The incidence and severity of PONV, need for rescue antiemetics, patient satisfaction score, duration of hospital stay, and the occurrence of adverse events were evaluated 48 hours post-surgery. Results : Data obtained from 97 patients were included in the final analysis. The incidence of PONV was significantly lower in the ramosetron group than in the control group throughout the 48-hour postoperative period (29.2% vs. 51.0%, p=0.028). A similar trend was observed with regard to PONV severity (p=0.041). The need for rescue antiemetics, satisfaction score, duration of hospital stays, and the occurrence of adverse events did not significantly differ between the groups. Conclusion : Prophylactic ramosetron administration reduced the incidence and severity of PONV in patients undergoing MVD without causing serious adverse events. Thus, ramosetron use may improve patient recovery following MVD.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.2
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• pp.117-128
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• 2006

Free flap transplantation with microvascular anastomosis has been successfully performed by development of surgical technique, materials and postoperative monitoring equipments of flap. But success rate of microvascular anastomosis is influenced by various factors, and failure rate is about 5-10%. The most influential factor for success rate is surgical technique and other factors that influence failure of microvascular anastomosis are ischemic time of free flap, thrombus formation of anastomosis region and vascular spasm. Many studies has been published in microvascular anastomosis with histologic effect for irrigating solution. But local irrigation solution has been used clinically in microvascular anastomosis, the comparison with each solution, microhistological study for endothelial cell repair and vascular patency has not been reported. The heparin which is anti-thrombotic agent, and urokinase which is fibrinolytic agent are used for this study. Vascular patency and thrombus formation in experimental micro-arterial anastomosis, and endothelial repair were observed with histologic analysis, scanning electron microscopy, transmission electron microscopic examination. The results were obtained as follows: 1. In vascular patency test in 30 minute and 7 days after micro-arterial anastomosis, equal effects of good vascular patency were obtained in group of local irrigation with heparin and urokinase. 2. In thrombus formation in 7 days after micro-arterial anastomosis, equal effects of minimal thrombus formation were obtained in group of local irrigation with heparin and urokinase. 3. In toluidin blue staining in 7 days after micro-arterial anastomosis, local destruction of endothelial cell and inner elastic lamina were seen and endothelial repair was not seen. 4. In scanning electron microscope examination in 7 days after micro-arterial anastomosis, endothelial cell was not seen in peripheral to suture materials, thrombus associated fibrin network was observed. 5. In transmission electron microscope examination in 7 days after micro-arterial anastomosis, inflammatory cell was seen within smooth muscle cells in site of endothelial cell destruction, smooth muscle cell around suture material were arranged irregularly, some collagenous change were seen. From the results obtained in this study, same results of good vascular patency and anti-thrombotic effect of heparin and urokinase were obtained as a local irrigation solution, and repair of endothelial cell was not seen in 7 days after micro-arterial anastomosis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.1
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• pp.93-101
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• 2011

Reconstruction following a resection of malignant oral cavity tumors is one of the most difficult problems in recent oral oncology. The radial forearm free flap (RFFF) is a thin, pliable soft tissue flap with large-caliber vessels for microvascular anastomosis. Its additional advantages include consistent flap vascular anatomy, acceptable donor site morbidity and the ability to perform simultaneous flap harvest with a tumor resection. For a better understanding of RFFF as a routine reconstructive procedure in oral and maxillofacial surgery, the constant anatomical findings must be learned and memorized by young doctors during the special curriculum periods for the Korean national board of oral and maxillofacial surgery. This review article discusses the anatomical basis of RFFF in the Korean language.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.5
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• pp.284-293
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• 2013

Purpose: For reconstruction of craniomaxillofacial defects caused by tumor, trauma, infection etc, free flap transplantation with microvascular surgery is a very useful method. Thrombus formation at the anastomosis site is the major cause of graft failure. 4-Hexylresorcinol (4-HR) is generally known as an antiseptic and antiparasitic agent. This study was conducted in order to evaluate the effect of 4-HR on blood coagulation in vitro. In addition, we investigated thrombus formation and endothelial repair of an injured vessel in an animal model. Methods: In the in vitro experiment, we compared blood coagulation time between the 4-HR treated group and normal blood. Thirty rats were used for in vivo animal experiments. After exposure of the right femoral vein, a micro vessel clamp was placed and the femoral vein was intentionally cut. Microvascular anastomosis was performed on all rats using 10-0 nylon under microscopy. The animals were divided into two groups. In the experimental group (n=15), 4-HR (250 mg/kg) mixed with olive oil (10 mL/kg) was administered per os daily. Animals in the control group (n=15) were given olive oil only. The animals were sacrificed at three days, seven days, and fourteen days after surgery and rat femoral vein samples were taken. Vascular patency and thrombus formation were investigated just before sacrifice. Histologic analysis was performed under a microscope. Results: Results of an in vitro blood coagulation test showed that coagulation time was delayed in the 4-HR treated group. The results obtained from an in vivo 4-HR administered rat model showed that the patency of all experimental groups was better at thirty minutes, seven days, and fourteen days after microvascular anastomosis than that of the control group at seven and fourteen days after anastomosis, and the amount of thrombus in the experimental groups was much less than that of the control group. Endothelial repair was observed in the histologic analysis. Conclusion: Findings of this study demonstrated that blood coagulation was delayed in the vitro 4-HR treated group. In addition, good vascular patency, anti-thrombotic effect, and repair of venous endothelial cells were observed in the vivo 4-HR administered rat group.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.4
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• pp.397-418
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• 1994

Microvascular surgery has been widely used in the clinical field of replantation and reconstructive surgery. Since the last 20 years, microsurgical techniques and instruments have been rapidly developed and the success rate is remarkably increased. But thrombotic occlusion of vessels remains the major reason for clinical failure. The change of vessel wall is the most important factor in thrombus formation. If we can reduce the traumatic changes in the vessel walls during surgery, the success rate can be markedly increased. For this study, femoral arteries and veins of 36 Sprague-Dawley rats with average weights of 300gm were used. The author observed the histological changes and healing process in the anastomostic site after 1 hour, 24 hours, 1, 2, 3 and 4 weeks under light microscopy and scanning electron microscopy. The results were as follows : 1. The patency rate was 100% in femoral arteries and 85% in femoral vein. 2. At the early stages after microvascular anastomosis, the loss of endothelial cell in the vessel walls was observed in the wide area including anastomotic site. In scanning electron microscopic finding the anastomotic site was covered with much fibrin, many red blood cells and some platelets. 3. At 1st week, new endothelial cells were formed toward anastomotic site and at 3rd week, the anastomotic site was completely covered by new endothelial cells. At 4th week, the complete endothelialization over the threads was observed. 4. The media extended from the anastomotic site toward the end of the specimen. At later stages, the extent of media necrosis was markedly decreased. But the media necrosis of anastomotic site was not regenerated till 4th week. 5. Intimal hyperplasia appeared at 1st week and increased till 4th week. The layer consisted of endothelialization the most luminal layers and smooth muscle in the deeper layers. But in veins, the response was less pronounced than in arteries. 6. Foreign body granuloma remained during 4 weeks and aneurysm was observed at 3rd week in artery. In aneurismal wall, media necrosis, loss of elastic lamina and intimal hyperplasia were seen.

• Archives of Reconstructive Microsurgery
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• v.20 no.1
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• pp.8-13
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• 2011

Purpose: A palatal defect following maxillectomy can cause multiple problems like the rhinolalia, leakage of foods into the nasal cavity, and hypernasality. Use of a prosthetic is the preferred method for obturating a palate defect, but for rehabilitating palatal function, prosthetics have many shortcomings. In a small defect, local flap is a useful method, however, the size of flap which can be elevated is limited. In 12 cases of palatomaxillary defect, we used various microvascular free flaps in reconstructing the palate and obtained good functional results. Method: Between 1990 and 2004, 12 patients underwent free flap operation after head and neck cancer ablation, and were reviewed retrospectively. Among the 12 free flaps, 6 were latissimus dorsi myocutaneous flaps, 3 rectus abdominis myocutaneous flaps, and 3 radial forearm flaps. Result: All microvascular flap surgery was successful. Mean follow up time was 8 months and after the follow up time all patients reported satisfactory speech and swallowing. Wound dehiscence was observed in 4 cases, ptosis was in 1 case and fistula was in 1 case, however, rhinolalia, leakage of food, or swallowing difficultly was not reported in the 12 cases. Conclusion: We used various microvascular flaps for palatomaxillary reconstruction. For 3-dimensional flap needs, we used the latissimus dorsi myocutaneous flap to obtain enough volume for filling the defect. Two-dimensional flaps were designed with latissimus dorsi myocutaneous flap, rectus abdominis flap and radial forearm flap. For cases with palatal defect only, we used the radial forearm flap. In palatomaxillary reconstruction, we can choose various free flap techniques according to the number of skin paddles and flap volume needed.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.124-130
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• 2005

In the microsurgical era, replantation with microvascular anastomosis is considered as the most superior method in aspects of texture, color, shape in case of nose amputation. There are some reported cases of replantation in nose amputation historically, but most of them are composite graft cases rather than microvascular anastomosis. Only a few cases of successful nasal replantation with microvascular anastomosis have been reported due to the reason that the size of vessels is usually very small and identifying suitable vessels for anastomosis is difficult. Microanastomosis of artery and microanastomosis of vein are ideal in replantation, but identifying suitable veins is often difficult. Without venous anastomosis, resolving the venous congestion remains to be a problem. We can carry out arteriovenous shunt if we can find two arteries in amputee. However, the smaller the size of amputee is, the more difficult it is to find two arteries. Instead of arteriovenous shunt, we can try external venous drainage(frequently swab, pin-prick, stab incision, IV or local heparin injection, dropping, apply of heparin-soaked gauze, use of medical leech). Here, we present three cases of replantation with microscopical arterial anastomosis (one angular artery, two dorsal nasal arteries) and external venous drainage (stab incision, application of medical leech and heparin-soaked gauze) even though the size of amputee may be as small as $1.5{\times}1.0cm$. In all cases, surgical outcomes were excellent in cosmetic and functional aspects. This report describes successful replantation by microvasular anastomosis in case that suitable veins are not found.

• 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.

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

• 대한미세수술학회:학술대회논문집
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• 1996.10a
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• pp.169-170
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• 1996