• 대한토목학회논문집
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• 제33권1호
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• pp.273-286
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• 2013

근래 지하철과 버스의 운영상 문제점이 대두되면서 신교통수단 도입이 요구되고 있다. 특히 여러 지자체들이 도입하고 있는 AGT방식의 경전철은 고가건설에 따른 도시미관 저해, 민원발생 등으로 건설이 지연되는 사례가 많아, 그에 대한 해결책으로 친환경적이고 접근이 편리한 노면전차가 대두되고 있다. 본 연구는 창원시를 친환경적인 대중교통지향형 도시로 탈바꿈 할 수 있도록 노면전차의 개요, 특징, 장 단점 등을 분석하고 이러한 시스템의 도입을 위해 기존의 대중교통수단간의 환승체계를 구축하기 위한 목적이다. 창원시 노면전차는 1단계 2018년, 2단계 2021년 개통을 목표로 추진 중에 있으며, 총 길이 33.9km 정거장 38개소를 건설할 계획이다. 2011년 예비타당성 조사에서는 B/C는 0.88로 경제성은 다소 떨어지나, 정책적 분석측면에서 AHP값이 0.502로 타당성이 있는 것으로 평가되었다. 다만 노면전차 도입 전에 선행되어야 할 과제로 첫 번째 노면전차의 도입시 버스를 포함한 대중교통 체계의 개편뿐만 아니라 자동차의 수요관리와 함께 이루어져야 하며, 국내 현실에 맞는 세심한 시스템 선정이 요구된다. 두 번째 철저한 시민공감대 형성 및 선진 시민의식이 제고되어야 하며, 노면전차의 도입에 필요한 법적인 제도가 확립되어져야 한다.

• Archives of Plastic Surgery
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• 제36권4호
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• pp.393-396
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• 2009

Purpose: Low - molecular - weight dextran is one of the most frequently used antithrombotic agents in microvascular surgery, but there is controversy if it has the real benefit in the clinical aspects. The purpose of this study was to evaluate the effect associated with postoperative use of low - molecular - weight dextran in breast reconstruction by free TRAM flap patients. Methods: From January 2002 to October 2008, we reconstructed 88 cases of postmastectomy deformity using the free TRAM flap. The 88 cases were divided into two groups : a group with no use of dextran(66 patients, control group, Group A) and a postoperative low - molecular weight dextran loaded group(22 patients, Group B). We assessed number of flap survival, rate of complication like hematoma or seroma, total amount of drainage from operative wound, duration of drainage, and amount of transfusion in each group. Results: There was no total flap loss and every flap was survived. Total amount of drainage for post - operative 5 days were 857 ml in group A and 1101 ml in group B. Drain was kept for average of 7.3 days in group A and 8.7 days in group B. Packed red cell transfusions were made in average of 3.3 units for group A and 3.0 units for group B. Group B showed significantly higher values in former 2 comparative parameters than group A. Conclusion: There was no definitive advantage of anticoagulants in elective free - flap surgery in terms of success rate. However, groups with using anticoagulants had the increased bleeding tendency in immediate postoperative period. The routine use of anticoagulants in elective free - flap surgery should be reconsidered with postoperatively less bleeding and early recovery.

• Archives of Plastic Surgery
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• 제32권4호
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• pp.408-415
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• 2005

Following a transverse rectus abdominis musculocutaneous(TRAM) flap breast reconstruction, denervated state of the flap causes the flap skin prone to thermal injury, calling for special attention. During the last 5 years, 69 breast reconstruction with 72 free TRAM flaps, were performed. Four out of thesse 69 patients sustained burn injury. Heat sources were a warm bag(n=2), heating pad(n=1) and warming light (n=1). The thermal injuries occured from 2 days to 3 months following the reconstruction. Three patients healed with conservative treatment, but one patient required debridement and skin graft. Initially 3 out of 4 patients with the burn had shown superficial 2nd degree burn with small blebs or bullae. However all 4 patients healed with scars. Mechanism of burn injuries of the denervated flap are known to be resulting from; 1) loss of behavioral protection due to denervation of flap with flap elevation and transfer, 2) loss of autonomic thermoregulatory control with heat dissipation on skin flap vasculature contributing to susceptibility of burn injury. 3) changes of immunologic and normal inflammatory response increasing thromboxane, and a fall in substance P & NGF (nerve growth factor). Including the abdominal flap donor site, sensory recovery of the reconstructed breast varies individually from 6 month even to 5 years postoperatively. During this period, wound healing is delayed, resulting in easier scarring compared to that observed in the sensate skin. Patients should be carefully informed and warned of possible burn injuries and taught to avoid exposure to heat source at least until 3 years postoperatively.

• Archives of Reconstructive Microsurgery
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• 제21권1호
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• pp.8-13
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• 2012

Purpose: Purpose: The free deep inferior epigastric artery perforator (DIEP) flap is a popular option for autologous breast reconstruction. However, the anatomy of the deep inferior epigastric artery(DIEA) may vary from one individual to another. Unexpected vascular anomaly can confuse the surgeon and affects on the safety of the free DIEP flap. Materials and Methods: Thirty five consecutive patients who underwent free DIEP/TRAM flap for immediate breast reconstruction between Mar. 2010 and Oct. 2010 were enrolled in this study. Computed tomography angiography (CT angiography) of abdomen was evaluated part of our standard preoperative assessment: atypical patterns of DIEA/DIEP were evaluated by preoperative CT angiography and compared with intraoperative finding. Results: Atypical patterns of DIEA/DIEP which may affect preoperative planning were noted as the following: Circummusclar/subfascial DIEA (n=1), DIEA running underneath rectus muscle (n=8), septocutaneous perforator (n=3), peritoneo-cutaneous perforator (n=1), a large branch going into peritoneum (n=1), and very early division and muscle penetration of DIEA (n=1). Conclusion: Atypical DIEA/DIEP that might change the operation plan is not rare, so the individualized planning based on the preoperative CT angiography is recommended. Preoperative CT angiography could help to select reliable and easy-to-dissect perforator in free DIEP/TRAM breast reconstruction.

• Structural Engineering and Mechanics
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• 제75권4호
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• pp.435-444
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• 2020

Ultrasonic guided wave testing is a very promising non-destructive testing method for rails, which is of great significance for ensuring the safe operation of railways. On the basis of the semi-analytical finite element (SAFE) method, a analytical model of 59R2 grooved rail was proposed, which is commonly used in the ballastless track of modern tram. The dispersion curves of ultrasonic guided waves in free rail and supported rail were obtained. Sensitivity analysis was then undertaken to evaluate the effect of rail elastic modulus on the phase velocity and group velocity dispersion curves of ultrasonic guided waves. The optimal guided wave mode, optimal excitation point and excitation direction suitable for detecting rail integrity were identified by analyzing the frequency, number of modes, and mode shapes. A sinusoidal signal modulated by a Hanning window with a center frequency of 25 kHz was used as the excitation source, and the propagation characteristics of high-frequency ultrasonic guided waves in the rail were obtained. The results show that the rail pad has a relatively little influence on the dispersion curves of ultrasonic guided waves in the high frequency band, and has a relatively large influence on the dispersion curves of ultrasonic guided waves in the low frequency band below 4 kHz. The rail elastic modulus has significant influence on the phase velocity in the high frequency band, while the group velocity is greatly affected by the rail elastic modulus in the low frequency band.

• Archives of Reconstructive Microsurgery
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• 제22권1호
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• pp.7-12
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• 2013

Purpose: Breast reconstruction with lower abdominal tissue can produce the best outcome with acceptable rates of long-term complication. However, for cases in which sufficient abdominal tissue is not available, an superior gluteal artery perforator (SGAP) flap can be considered as the next option for autologous breast reconstruction. Materials and Methods: Among a total of 63 women who underwent breast reconstruction with free autologous tissue transfer from July 2010 to April 2011, SGAP flap was performed for four patients. In two cases, patients did not have enough abdominal tissue for sizable breast reconstruction. In another case, the patient had a long abdominal scar due to donor hepatectomy of liver transplantation. In the last case, which was a revisional case after radiation necrosis of a previous pedicled transverse rectus abdominis musculocutaneous (TRAM) flap, a large amount of healthy skin and soft tissue was needed. SGAP flap was elevated in lateral decubitus position. The internal mammary vessels were used for recipient vessels in all cases. Results: Breast reconstruction was performed successfully in all four cases without flap loss. Donor site complication was not observed, except for one case of seroma. The shape of the reconstructed breast was satisfactory in all patients. Conclusion: SGAP flap is an excellent alternative option for the TRAM or deep inferior epigastric artery perforator flap for breast reconstruction. In terms of narrower width, harder consistency of soft tissue, and shorter pedicle, it is clear that the SGAP flap is less competent than the TRAM flap. However, in cases where abdominal tissue is not available, SGAP flap is the only way of providing a large amount of healthy tissue.

• Archives of Plastic Surgery
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• 제45권5호
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• pp.441-448
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• 2018

Background Previously, surveys have been used to investigate breast reconstruction statistics. Since 2015, breast reconstruction surgery after mastectomy has been covered by the National Health Insurance Service in Korea, and data from breast reconstruction patients are now available from the Health Insurance Review and Assessment Service (HIRA). We investigated statistics in breast reconstruction in Korea through statistics provided by the HIRA Big Data Hub. Methods We investigated the number of cases in mastectomy and breast reconstruction methods from April 1, 2015 to December 31, 2016. Data were furnished by the HIRA Big Data Hub and accessed remotely online. Results were tabulated using SAS Enterprise version 6.1. Results The 31,155 mastectomy cases included 7,088 breast reconstruction cases. Implant-based methods were used in 4,702 cases, and autologous methods in 2,386. The implant-based reconstructions included 1,896 direct-to-implant and 2,806 tissue-expander (2-stage) breast reconstructions. The 2-stage tissue-expander reconstructions included 1,624 expander insertions (first stage) and 1,182 expander-to-permanent-implant exchanges (second stage). Of the autologous breast reconstructions, 705 involved latissimus dorsi muscle flaps, 498 involved pedicled transverse rectus abdominis myocutaneous (TRAM) flaps, and 1,183 involved free-tissue transfer TRAM flaps, including deep inferior epigastric perforator free-tissue transfer flaps. There were 1,707 nipple-areolar complex reconstructions, including 1,565 nipple reconstructions and 142 areola reconstructions. The 1-year mean number of breast reconstructions was 4,050. Conclusions This was the first attempt to evaluate the total number of breast reconstruction procedures using accurate, comprehensive data, and our findings may prove valuable as a foundation for future statistical studies of breast reconstruction procedures in Korea.

• Archives of Plastic Surgery
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• 제32권2호
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• pp.231-236
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• 2005

Nowadays breast reconstruction with autologous tissues after radical mastectomy is commonly performed, and a natural inframammary fold in the reconstructed breast is considered to be an essential aspect of symmetrical breast shape and location. Total of 104 patients underwent breast reconstruction with free TRAM flap and formation of inframammary fold with free TRAM breast reconstruction was done in 79 patients. No suture fixation for inframammary fold were done in 19 patients. 27 patients(24.0%) were made of inframammary fold with absorbable suture, 52 patients (50.0%) underwent inframammary fold creation with nonabsorbable suture. There were 4 cases(16.0%) of displacement of reconstructed breast and 2 cases(8.0%) of partial disruption of inframammary fold in the group of no suture. There were 2 cases(7.4%) of displacement of reconstructed breast and 3 cases(11.1%) of partial disruption of inframmamary fold in the fixed group with absorbable suture. There was only 1 case(1.9%) of partial disruption of inframammary fold fixed with nonabsorbable suture group. Therefore, we could speculate that the reinforcement of ligamentous structure for making the definite inframammary fold is necessary, and the area of the inframammary fold should not be undermined in immediate breast reconstruction as much as possible in order to preserve the zone of adherence. If the fold is disrupted during the mastectomy, it should be re-created with the non-absorbable sutures. Nonabsorbable suture fixation seemed to be more stable than absorbable suture. Preoperative marking and design are very important to make the symmetrical shape and location of inframammary fold in both of immediate and delayed reconstruction of breasts.

• Archives of Reconstructive Microsurgery
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• 제11권2호
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• pp.141-145
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• 2002

Rectus abdominis muscle free flap is widely used for breast reconstruction and soft tissue defect in lower leg but donor-site morbidities such as abdominal wall weakness, hernia, bulging are troublesome. Recently, to minimize donor-site morbidity, there has been a surge in interest in deep inferior epigastric perforator(DIEP) free flap preserving the anatomy of rectus abdominis muscle, fascia, and motor nerve. Between August of 1995 and September of 2002, topographic investigation of DIEP was performed during the elevation of 97 cases of TRAM free flap and 5 cases of DIEP free flap. There were 84 cases of breast reconstructions, 12 cases of lower leg reconstructions, and 6 cases of head and neck reconstruction. We could observe total 10 to 12 perforators on each rectus abdominis muscle below umbilicus. Among these, the numbers of large perforators(>1.5mm of diameter) were mean 2.1 in lateral half of rectus abdominis muscle, mean 1.2 in medial half, and mean 0.5 in linea alba and paramedian. DIEP free flap provides ample amount of well vascularized soft tissue without inclusion of any rectus abdominis muscle and fascia and minimizes donor-site morbidity. One perforator with significant flow can perfuse the whole flap. For large flap, a perforator of the medial row provides better perfusion to zone-4 than one of lateral row and, if diameter of perforator is small, $2{\sim}3$ perforators can be used. According to the condition of recipient-site, thin flap can be harvested. As DIEP free flap has many advantage, perforator topography will be useful in increasing clinical usage of DIEP free flap.

• Archives of Plastic Surgery
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• 제36권6호
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• pp.750-754
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• 2009

Purpose: The thoracodorsal vessels have been the standard recipient vessels for the majority of surgeons performing free abdominal flap breast reconstructions. Recently, the internal mammary vessels have been recommended as the first - choice recipient vessels for microvascular breast reconstruction. To approach the internal mammary vessel, 3rd or 4th rib cartilage excision is needed, but this method has some demerits - vessel injury, post operative pain and post operative chest hollowness. So, authors propose the approach method to the internal mammary vessel through intercostal space without rib cartilage resection. Methods: From November, 2008 to May, 2009, 13 patients underwent free abdominal flap breast reconstruction with approach to the internal mammary vessel through intercostal space without rib cartilage resection. Results: The mean patient age was 41.8 years, and the mean height was 159.3 cm. 11 patients underwent immediate breast reconstruction. Free DIEP flap reconstruction was performed in 7 patients, Free TRAM flap was performed in 5 patients, and Free SIEA flap was performed in 1 patient. Except 1 case, approach to the internal mammary vessel was took through 3rd intercostal space, and all width of intercostal space exceeded 1 cm. Conclusion: In the authors' experience, use of approach to the internal mammary vessels without rib cartilage resection method is safe and reliable to overcome demerits of rib cartilage resection method.