• Archives of Reconstructive Microsurgery
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• v.7 no.2
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• pp.114-121
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• 1998

The purpose of this study is to investigate the appropriate management of severe radionecrotic wounds of the anterior chest wall associated with infection of the soft tissues and ribs and exposure of vital structures(heart and lung), and present our strategies for reconstruction of these complicated patients. 9 patients have undergone radical debridement and immediate microsurgical reconstruction for severe radionecrotic wounds of the anterior chest wall over last 7 years. All patients had extensive osteomyelitis of the ribs or sternum, and chronic infection or cutaneous fistulae. 2 patients had pericardial effusions due to longstanding inflammation, and 6 patients had pleural effusions. 2 patients had ipsilateral lung collapse. 10 free flaps were performed for coverage of the huge defects. One patient required 2 free flaps to control the inflammation. 8 free TRAM flaps were used for coverage of the defects and in addition, the rectus abdominis muscle was packed into any deep cavity. 1 patients underwent latissimus dorsi muscle free flap because of previous abdominal surgery. After extensive debridement of the infected, radionecrotic wounds, all 10 free flaps were successful. All the extensive radionecrotic defects of the anterior chest wall were completely healed. Free flaps successfully covered the exposed vital structures of the heart and lungs. Patients with severe radionecrotic defects of the anterior chest wall after ablative breast cancer surgery and radiotherapy were successfully treated by radical debridement and immediate free flap surgery. The TRAM flap together with the rectus muscle is the treatment of choice for these huge defects. The latissimus dorsi muscle flap was the second choice in patients with previous abdominal surgery. The recipient vessel should be carefully selected because of possible radiation damage and inflammation.

• Archives of Plastic Surgery
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• v.39 no.6
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• pp.631-635
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• 2012

Background The evaluation of a breast after breast reconstruction depends on a surgeon's subjective criteria. We used computed tomography (CT) scans to obtain an objective evaluation of the postoperative results by measuring the breast volume of patients who had undergone breast reconstruction using pedicled transverse rectus abdominis myocutaneous (TRAM) flaps. This research will help in the objective postoperative evaluation of reconstructed breasts, and also in the preoperative flap size designs. Methods A total of 27 patients underwent breast reconstruction using pedicled TRAM flaps after mastectomy from September 2007 to July 2010. Of these, 10 patients who were followed up and underwent CT scans 2 or more times during the follow-up period were included in this study. We evaluated the change in breast volume over time using CT scans, and the interval breast volume change between CT scans. Results All of the 10 patients' reconstructed breasts showed a volume decrease over time. The breast volume changes in the intervals between CT scans were as follows: 5.65% decrease between the first CT and second CT scan, 2.3% decrease between the second CT and third CT scan, (statistically significant) and 1.89% decrease between the third CT and forth CT scan. (not statistically significant). Conclusions This research shows the possibility of objectively evaluating the postoperative breast volume changes. The findings will be helpful in designing the size of TRAM flaps to use on defects after mastectomy. Based on these results, we should also closely observe the reconstructed breast volume for at least 2 years.

• Archives of Plastic Surgery
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• v.43 no.5
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• pp.424-429
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• 2016

Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A $1{\times}2-cm$ acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was $73.0%{\pm}9.67%$ for the LD flap group using an O-strut, $72.0%{\pm}11.53%$ for the TRAM flap group using an I-strut, and $69.0%{\pm}10.82%$ for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction.

• Archives of Reconstructive Microsurgery
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• v.22 no.1
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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.

• Journal of the Korean Society for Railway
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• v.12 no.4
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• pp.518-525
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• 2009

This paper describes the evaluation of structural performance test and finite element analysis to verify the design of Bimodal Tram made of sandwich composites. The sandwich composite applied to vehicle structure was composed of a aluminum honeycomb core and WR580/NF4000 glass fabric/epoxy laminate composite facesheet. The load tests of vehicle structure were conducted for vertical load, compressive load, torsion and modal analysis according to JlS E 7105. The structural Integrity of vehicle was evaluated by the measurement of displacement, stress and natural frequency obtained from dial gauge, strain gauge and gravity sensor, respectively. And finite element analysis using ANSYS v11.0 was done to compare with structural test. The results showed that the displacement, stress and natural frequency were in an good agreement with those of structural analysis using the proposed finite element models.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.45-52
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• 2010

This paper estimated the impact factor using the finite element program to confirm the dynamic behavior of new type of bridges constructed by introduction of new vehicles and compared the design criteria about the impact factor applied to domestic as well as each country. The study estimated effects of the impact factor according to pipe truss types modeled as respectively 34m, 44m, 54m and span length. The vehicle models are vehicle for bimodal tram of two axis and three axis which passes on actual bridge and dump truck model proposed by Park Young suk(1997). Each vehicle is estimated the impact factor according to velocity from 10 to 100(km/h) and examined. Also, the study investigated and compared the design regulation of domestic and a foreign country based on the impact factor on span center calculated in accordance with vehicle and span length.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.715-717
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• 2011

Purpose: In cases of breast reconstruction with a free transverse rectus abdominis musculocutaneous (TRAM) flap after skin-sparing mastectomy with nipple-areolar complex (NAC) removal, the flat contour of the flap's skin paddle can easily look unnatural and dissatisfying. Reconstructed NAC on the flap surface lacks the elevated contour that the normal areola possesses, resulting in an unnatural final result. Therefore, we would like to introduce a novel method to improve this problem and report the satisfactory results we obtained. Methods: Operations were conducted on 19 patients who underwent immediate breast reconstruction with a free TRAM flap and skin-sparing mastectomy from January 2009 to January 2010, with a mean follow-up of nine months. While the TRAM free flap was being inset, a purse-string suture was carried out on the dermal layer of skin flap to create a slight protrusion with Gore-$Tex^{(R)}$ sutures. Results: The elevated mound surrounding the NAC was well maintained for an average follow-up period of nine months. Nipple projection was also well maintained. There was no complaint about breast contour or nipple height reduction. In addition, there was no reported incidence of other complications. Conclusion: The purse-string suture technique presents a more natural breast silhouette around the NAC and helps to maintain nipple projection. Furthermore, it does not require any supplementary incisions or complicated skills. There has been no report of additional complications using this technique.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.717-724
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• 2017

To improve the running safety of a tram operating on a concrete embedded track, a bogie, the core system of the tram, was developed and fabricated. After it was integrated with the prototype car body, a short distance track with a sharp curve and steep gradient was constructed for the test operation. A formula to check the interference of the wheel flange with the track during running was proposed. Based on the results provided by the formula, the track was designed. Another simple formula was derived to estimate the derailment quotient and the wheel unloading ratio. During running on the track, the acceleration of the car body was measured and the interface status between the wheel and the track was monitored by a video system. According to the results calculated by these simple formulas, the derailment quotient and wheel unloading ratio were estimated to be within the safety criteria. In the actual test, no derailment occurred and the measured acceleration satisfied the criteria. Also, there was no interference between the wheel and track. The video monitoring results showed no signs of derailment, such as the climbing of the wheel. The pinion in the center showed good running safety, contacting smoothly with the rack. The measurements of environmental noise proved that the criteria were satisfied.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.12-18
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• 2005

The Transverse rectus abdominis musculocutaneous (TRAM) flap has been commonly used for autologous breast reconstruction. Despite these clinical usefulness, the TRAM flap is prone to partial flap or fat necrosis in especially pedicled flap. To improve flap survival, the surgical delay procedures and pharmacological treatments have been developed. In many studies for the pharmacological treatment, Lipo-$PGE_1$ has demonstrated a marked ability to improve flap survival and it's effect has been proved similar to surgical delay procedure. The purpose of this study is to determine the most effective route of Lipo-$PGE_1$ administration as a pharmacological treatment in TRAM flap of the rat. Fifty male Sprague-Dawley rats weighing 300-350 gm were divided into five groups, One week before flap elevation, Lipo-$PGE_1$($2{\mu}g/kg$) was injected three times in a week and than the left inferior epigastric vessel based TRAM flap ($5.0{\times}3.0cm$) elevated; group I: no procedure before flap elevation; group II: intraperitoneal injection; group III: intravenous injection; group IV: subcutaneous injection; group V: topical application. A flap was assessed at postoperative 7 days by comparison of flap survival rate, vessel counts(H-E stain), and vascular endothelial growth factor(VEGF) protein expressed by Western blot. The results demonstrated that the mean percentages of the flap survival area in group III were significantly higher than that of any other group(p<0.05). The vessel counts of all experimental groups were statistically higher than that of control group(p<0.05). Only in group III, the VEGF protein expression was increased significantly than control group and there are no difference in other experimental groups. In conclusion, the intravenous administration of the Lipo-$PGE_1$ is the most effective on flap survival, and the VEGF induced by Lipo-$PGE_1$ has some positive effects on new vessel formation and flap survival.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.163-168
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• 2007

Purpose: The flap delay is a widely used technique to increase the flap survival. Dexamethasone is a well-known drug to have a positive impact on the flap survival. The objective of this study is to investigate the dual synergic effect of epinephrine as a chemical delay agent plus dexamethasone on the TRAM flap survival in rat model. Methods: Forty Sparague-Dawley rats were divided into 4 groups evenly and a right inferior epigastic vessel pedicled TRAM flap, sized $5.0{\times}3.0cm$, was elevated on each upper abdomen. In the control group(N=10), 2 ml saline was injected on transverse abdominis muscle for a week before the flap elevation. In surgical delay group(N=10) all superior pedicles and left inferior pedicle were ligated a week before the flap elevation. In epinephrine group (N=10), 1 : 50000 epinephrine mixed saline was injected to transverse abdominis muscle every day for a week before flap elevation. In epinephrine plus dexamethasone group (N=10), the same procedure as that of epinephrine group was conducted for a week and 2.5 ml/kg dexamethasone was injected transverse abdominis muscle 2 hours before the flap elevation. On the seventh day after flap elevation, the survival area of flaps were measured and the vessel numbers in upper dermis of flap were counted through histologic slides. Results: The results were as follows: the mean percentage of the flap survival area of surgical delay group ($60.5{\pm}2.44%$), epinephrine group ($75{\pm}4.43%$), and epinephrine plus dexamethasone group ($87{\pm}1.94%$) were higher than that of the control group ($35{\pm}6.06%$) significantly(p<0.05). In case of the vessel number though histologic slides, epinephrine group ($79.3{\pm}5.57$) and epinephrine plus dexamethasone group ($96.3{\pm}14.05$) were higher than that of the control group ($44.8{\pm}8.82$) significantly(p<0.05), but the surgical delay group ($54{\pm}4.23$) showed no significant difference (p>0.05) compared to that of the control group. Conclusion: The results indicated that epinephrine plus dexamethasone injection before the flap elevation could be used to increase the TRAM flap survival area in rat model.