• Progress in Superconductivity and Cryogenics
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• v.17 no.3
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• pp.13-17
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• 2015

In superconducting coil applications particularly in wet wound coils, coated conductor (CC) tapes are subjected to different type of stresses. These include hoop stress acting along the length of the CC tape and the Lorentz force acting perpendicular to the CC tape's surface. Since the latter is commonly associated with delamination problem of multi-layered CC tapes, more understanding and attention on the delamination phenomena induced in the case of coil applications are needed. Difference on the coefficient of thermal expansion (CTE) of each constituent layer of the CC tape, the bobbin, and the impregnating materials is the main causes of delamination in CC tapes when subjected to thermal cycling. The CC tape might also experience cyclic loading due to the energizing scheme (on - off) during operation. In the design of degradation-free superconducting coils, therefore, characterization of the delamination behaviors including mechanism and strength in REBCO CC tapes becomes critical. In this study, transverse tensile tests were conducted under different loading conditions using different size of upper anvils on the GdBCO CC tapes. The mechanical and electromechanical delamination strength behaviors of the CC tapes under transverse tensile loading were examined and a two-parameter Weibull distribution analysis was conducted in statistical aspects. As a result, the CC tape showed similar range of mechanical delamination strength regardless of cross-head speed adopted. On the other hand, cyclic loading might have affected the CC tape in both upper anvil sizes adopted.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.341-347
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• 2013

Background Intractable chronic scalp ulcers with cranial bone exposure can occur along the incision after cranioplasty, posing challenges for clinicians. They occur as a result of severe scarring, poor blood circulation of the scalp, and focal osteomyelitis. We successfully repaired these scalp ulcers using a vascularized bipedicled pericranial flap after complete debridement. Methods Six patients who underwent cranioplasty had chronic ulcers where the cranial bone, with or without the metal plate, was exposed along the incision line. After completely excising the ulcer and the adjacent scar tissue, subgaleal dissection was performed. We removed the osteomyelitic calvarial bone, the exposed metal plate, and granulation tissue. A bipedicled pericranial flap was elevated to cover the defect between the bone graft or prosthesis and the normal cranial bone. It was transposed to the defect site and fixed using an absorbable suture. Scalp flaps were bilaterally advanced after relaxation incisions on the galea, and were closed without tension. Results All the surgical wounds were completely healed with an improved aesthetic outcome, and there were no notable complications during a mean follow-up period of seven months. Conclusions A bipedicled pericranial flap is vascularized, prompting wound healing without donor site morbidity. This may be an effective modality for treating chronic scalp ulcer accompanied by the exposure of the cranial bone after cranioplasty.

• Korean Journal of Cleft Lip And Palate
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• v.8 no.1
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• pp.31-37
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• 2005

In alveolar deformity of cleft patient, the flap design is very important to make the functional and esthetic outcome. Especially in bilateral cleft alveolus with wide defect, deficiency of covering tissue is a greatest problem. Wound dehiscence may develop oronasal fistula of palatal and labial region and loss of the bone graft. We report 2 cases with bilateral cleft alveolus. In both case, bilateral buccal mucosal flap was used for closure of bilateral cleft alveolus with wide defect. The one was operated with iliac bone graft according to secondary grafting method, the other was closed without bone grafting. The patient was 3 years old. So, secondary alveolar bone graft will be required some years later for the establishment of bony continuity and esthetic advantage. In both cases, we found the entire soft tissue closure without the lack of covering flap. In these case, the closure of alveolus defect was accomplished successfully by the use of bilateral buccal mucosal flap. There was no complication, secondary fistula. The most important thing is the tension-free closure of the bilateral buccal mucosal flap. So, we report these cases with literatures.

• Archives of Plastic Surgery
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• v.41 no.3
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• pp.271-276
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• 2014

Background As the obese population increases in Korea, the number of patients who are trying to lose weight has been increasing steadily. In these patients, skin laxity and deformation of the body contour occurs, which could possibly be corrected by various body contouring surgeries. Here, we introduce the brachioplasty method and our experience of various body contouring surgeries performed in our center. Methods From November 2009 to August 2011, five cases of brachioplasty were performed. When the patient presented with sagging of the lateral inframammary crease and bat wing deformity in the axilla, extended brachioplasty was performed; in this case, the deformation of the axilla and lateral chest was corrected at the same time. A traditional brachioplasty was performed when contouring was needed only for skin laxity in the upper arm. Results Complications, such as hematomas or nerve injuries, were not evident. Some patients experienced partial wound dehiscence due to tension or hypertrophic scars found during the follow-up. In general, all of the patients were satisfied with the improvement in their upper arm contour. Conclusions Given the demands for body contouring surgery, the number of brachioplasty surgical procedures is expected to increase significantly, with abdominoplasty comprising a large portion of these surgeries. For the brachioplasty procedure, preparation and preoperative consultation regarding design of the surgery by experienced surgeons was important to prevent complications such as nerve damage or hematoma formation.

• Archives of Plastic Surgery
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• v.41 no.3
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• pp.258-263
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• 2014

Background For early breast cancer patients, skin-sparing mastectomy or nipple-sparing mastectomy with sentinel lymph node biopsy has become the mainstream treatment for immediate breast reconstruction in possible cases. However, a few cases of skin necrosis caused by methylene blue dye (MBD) used for sentinel lymph node localization have been reported. Methods Immediate breast reconstruction using a silicone implant was performed on 35 breasts of 34 patients after mastectomy. For sentinel lymph node localization, 1% MBD (3 mL) was injected into the subareolar area. The operation site was inspected in the postoperative evaluation. Results Six cases of immediate breast reconstruction using implants were complicated by methylene blue dye. One case of local infection was improved by conservative treatment. In two cases, partial necrosis and wound dehiscence of the incision areas were observed; thus, debridement and closure were performed. Of the three cases of wide skin necrosis, two cases underwent removal of the dead tissue and implants, followed by primary closure. In the other case, the breast implant was salvaged using latissimus dorsi musculocutaneous flap reconstruction. Conclusions The complications were caused by MBD toxicity, which aggravated blood disturbance and skin tension after implant insertion. When planning immediate breast reconstruction using silicone implants, complications of MBD should be discussed in detail prior to surgery, and appropriate management in the event of complications is required.

• Journal of Trauma and Injury
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• v.30 no.4
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• pp.145-157
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• 2017

Purpose: We accessed epidemioloy of 908 acute burns (7 years) in the military, of injuries and propose proper educational programs to suit community. Methods: We surveyed burn demographics, circumstances of injuries, size, result of treatment. Results: The mean age was 20.6 years. The flame burns (FB) (325, 35.8%) were most common, followed scald (SB) (305, 33.6%), contact (CB) (219, 24.1%), electric (EB) (45, 5.0%) and chemical burns (ChB) (14, 1.5%). The more occurred during winter (29.7%). SB had mean 3.9% total body surface area (TBSA). The 251 (82.3%) had superficial burns by spillage of hot water/food on lower limbs (45.6%), feet (33.8%) in summer (34.8%), treated with simple dressing (92.8%). Morbidity rate was 5.6%; post traumatic stress disease (PTSD) (0.7%). FB had large wound (9.3% TBSA). The 209 (64.3%) had superficial burns by ignition to flammable oils (31.7%) and bomb powders (29.2%) on head/neck (60.3%), hands (58.6%) in summer (31.7%), autumn (30.2%). They underwent simple dressing (83.4%) and skin graft (16.0%). Morbidity rate was 18.8%; PTSD (10.5%), inhalation injuries (4.0%), corneal injury (3.7%), amputations (0.9%), and mortality rate (1.2%). CB had small (1.1% TBSA), deep burns (78.5%) by hotpack (80.4%) on lower limbs (80.4%). The more (59.8%) underwent skin graft. EB had 6.8% TBSA. The 29 (64.4%) had superficial burns by touching to high tension cable (71.1%) on hand (71.1%), upper limbs (24.4%) in autumn (46.8%). They underwent simple dressing (71.1%) and skin graft (24.4%). They showed high morbidity rate (40.0%); loss of consciousness (13.3%), nerve injuries (11.1%), neuropathy (8.9%), amputations (2.2%), and mortality rate (2.2%). Conclusions: The cook should wear apron over the boots during work. The lighter or smoking should be strictly prohibited during work with flammable liquids or bomb powders. Don't directly apply hotpack to skin for a long time. Use insulating glove during electric work. Keep to the basic can prevent severe injury and proper education is important.

• Journal of Chest Surgery
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• v.26 no.2
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• pp.89-95
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• 1993

30 patients with spontaneous pneumothorax underwent videothoracoscopic treatment between March and July 1992. The patients ranged in age from 16 years to 62 years (mean age, 30.4 years) and the incidence according to age group was highest as 50 % in the adolescence between 21 and 30 years old. The indications of the therapeutic videothoracoscopy for spontaneous pneumothorax were recurrence (30.8％), persistent air leak (30.8％), visible blebs on the chest X-ray (20.4％), tension pneumothorax (15.4％), and bilaterality (2.6％). Intraoperative scopic findings were as follows; blebs (87.1％), pleural adhesion (45.2％), and pleural effusion (22.6％). The operation was performed under general anesthesia with one lung intubation guided by flexible fiberoptic bronchoscopy. Procedures included bleb and/or wedge resection, tetracycline pleurodesis with mechanical abrasion, and parietal pleurectomy. Successful treatment was obtained in 66.7％ (20/30) and the mean postoperative hospital stay of the successful cases was 5 days. Videothoracoscopy also provided the benefits of lesser postoperative pain, rapid recovery, short hospitalization, and smaller scar of wound by reduced trauma on access. The total 13 postoperative complications were occured in 10 patients, which showed somewhat higher rate than that of other reports because of lack of experiences in the earlier period, however, it had decreased progressively as experiences were accumulated and instruments were improved in the later period. The operative mortality was absent. Conclusively, videothoracoscopy is a new interesting modality of surgical treatment of spontaneous pneumothorax and also can be extensively applicable in the diagnosis and treatment of other thoracic surgery.

• Archives of Plastic Surgery
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• v.33 no.1
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• pp.131-134
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• 2006

The closed suction drain is commonly inserted after various surgical procedures. It has an important role to prevent possible hematoma or seroma that can cause postoperative wound problems. But there is still no consensus on managing the insertion site of suction drain after operation. Suture-tie fixation of drain to skin and classical Y shape gauze dressing is a usually accepted method, but it has many limitations. We introduce a new approach to the care for the insertion site of suction drain by using occlusive transparent film dressing, $IV3000^{(R)}$(Smith & Nephew, London, UK). By using transparent film, insertion site of drain can be easily checked without removal of dressing. Because it can reduce the tension of suture-tie fixation, it helps to prevent skin injury. Furthermore, occlusive film dressing can block air leakage from insertion site of drain, and the water-proof character of film allows patients to take a shower without dressing change. This new method is more convenient, more efficient, and less harmful to skin than classic one.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1508-1515
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• 1992

Between 1975 and 1992, forty five patients with trachea stenosis received tracheoplasty for relief of obstruction. The causes of airway problem are brain contusion[19 cases, 40%], cerebrovascular disease[3 cases, 7%], drug intoxication[8 cases, 18%], psychotic problem[2 cases, 4%], trachea tumor[3 cases, 7%], adult respiratory distress syndrome[9 cases, 20%] and direct trauma[1 case, 2%]. Direct causes of trachea stenosis were complications of tracheostomy[36 cases, 80%], complications of nasotracheal intubation[5 cases, 11%], tumor[3 cases, 6%] and trauma[1 case, 2%]. Thirty one patients underwent the sleeve resection and end-to-end anastomosis. Five patients performed a wedge resection and end-to-end anastomosis. Forteen patients received the Montgomery T-tube for relief of airway obstruction. Four patients have done simple excision of granulation tissue. Two, subglottic stenosis patients were received Rethi procedure[anterior division of cricoid cartilage, wedge partial resection of lower thyroid cartilage and Montgomery T-tube molding] and the other subglottic stenosis patient underwent permanent trachea fenestration. Including cervical flexion in all patients postoperatively, additional surgical techniques for obtain tension-free anastomosis were hyoid bone release technique in two cases, and hilar mobilization, division of inferior pulmonary ligament and mobilization of pulmonary vessel at the pericardium were performed in one case. Cervical approach was used in 39 cases, cervicomediastinal in 12 cases and transthoracic in one case. Complications of tracheoplasty were formation of granulation tissue at the anastomosis site[3 cases], restenosis[9 cases], trachea-innominate artery fistula[2 cases], wound infection[2 cases], separation of anastomosis[2 cases], air leakage[3 cases], injury to a recurrent laryngeal nerve[temporary 8 cases, permanent 2 cases] and hypoxemia[1 case]. Surgical mortality for resection with primary reconstruction was 6.7%, with one death due to postoperative respiratory failure and two deaths due to tracheo-innominate artery fistula.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.67-72
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• 2008

Purpose: The hand is frequently affected area in high voltage electrical burn injury as an input or output sites. Electrical burn affecting the hand may produce full thickness necrosis of the skin and damage deep structures beneath the eschar, affecting the tendon, nerve, vessel, even bone which result in serious dysfunction of the hand. As promising methods for the reconstruction of the hand defects in electrical burn patients, we have used the peroneal perforator free flaps. Methods: From March 2005 to June 2006, we applied peroneal perforator free flap to five patients with high tension electrical burn in the hand. Vascular pedicle ranged from 4cm to 5cm and flap size was from $4{\times}2.5cm$ to $7{\times}4cm$. Donor site was closed primarily.Results: All flaps survived completely. There was no need to sacrifice any main artery in the lower leg, and there was minimal morbidity at donor site. During the follow-ups, we got satisfactory results both in hand function and in aesthetic aspects.Conclusion: The peroneal perforator flap is a very thin, pliable flap with minimal donor site morbidity and is suitable for the reconstruction of small and medium sized wound defect, especially hand with electrical burn injury.