• 대한기계학회논문집B
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• 제25권6호
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• pp.786-798
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• 2001

This paper describes the phenomena of wake-induced transition of the boundary layers on a NACA0012 airfoil using measured phase-averaged data. Especially, the phase-averaged wall shear stresses are reasonably evaluated using the principle of Computational Preston Tube Method. Due to the passing wake, the turbulent patch is generated in the laminar boundary layer on the airfoil and the boundary layer becomes temporarily transitional. The patches propagate downstream with less speed than free-stream velocity and merge with each other at further down stream station, and the boundary layer becomes more transitional. The generation of turbulent patch at the leading edge of the airfoil mainly depends on velocity defects and turbulent intensity profiles of passing wakes. However, the growth and merging of turbulent patches depend on local streamwise pressure gradients as well as characteristics of turbulent patches. In this transition process, the present experimental data show very similar features to the previous numerical and experimental studies. It is confirmed that the two phase-averaged mean velocity dips appear in the outer region of transitional boundary layer for each passing cycle. Relatively high values of the phase-averaged turbulent fluctuations in the outer region indicate the possibility that breakdown occurs in the outer layer not near the wall.

• Archives of Plastic Surgery
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• 제40권2호
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• pp.91-96
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• 2013

Background A thinned anterolateral thigh (ALT) flap is often harvested to achieve optimal skin resurfacing. Several techniques have been described to thin an ALT flap including an adipocutaneous flap, an adipofascial flap and delayed debulking. Methods By systematically reviewing all of the available literature in English and French, the present manuscript attempts to identify the common surgical indications, complications and donor site morbidity of the adipofascial variant of the ALT flap. The studies were identified by performing a systematic search on Medline, Ovid, EMBASE, the Cochrane Database of Systematic Reviews, Current Contents, PubMed, Google, and Google Scholar. Results The study selection process was adapted from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, and 15 articles were identified using the study inclusion criteria. These articles were then reviewed for author name(s), year of publication, flap dimensions and thickness following defatting, perforator type, type of transfer, complications, thinning technique, number of cases with a particular area of application and donor site morbidity. Conclusions The adipofascial variant of the ALT flap provides tissue to fill large defects and improve pliability. Its strong and safe blood supply permits adequate immediate or delayed debulking without vascular complications. The presence of the deep fascia makes it possible to prevent sagging by suspending and fixing the flap for functional reconstructive purposes (e.g., the intraoral cavity). Donor site morbidity is minimal, and thigh deformities can be reduced through immediate direct closure or liposuction and direct closure. A safe blood supply was confirmed by the rate of secondary flap debulking.

• Archives of Reconstructive Microsurgery
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• 제6권1호
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• pp.56-62
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• 1997

Latissimus dorsi(LD) muscle is the largest transplantable block of vascularized tissue. Since LD free flap was introduced in 1970's, this flap has been widely used for the reconstruction of large soft tissue defect of the limb. From 1981 to 1996, we had experienced 37 cases of LD free flap. Serratus anterior muscle was combined with LD in three of them whose defects were very large. The average age of the patients was 31 years(range : 4-74 years), and thirty one patients were male. Trauma was cause of the defect in every case. For the recipient sites, the foot and ankle was the most common(22 cases); and the knee and lower leg(11 cases), the elbow and forearm(2 cases), the hand(2 cases) were the next. The duration of follow-up was averaged as 16 months(range: 6 months-12 years). Thirty one cases(84%) out of 37 were successful transplantations. In one case the failure of the flap was due to heart attack and subsequent death of the patient. One failure was caused by sudden violent seizure of the patient who had organic brain damage. Immediate reexploration of the flap was performed in 4 patients, and the flap survived in three of them. There was one necrosis of the grafted split-thickness skin on the survived LD flap. LD free flap was considered as one of the good methods, for the reconstruction of the large soft tissue defect of the limb.

• Archives of Plastic Surgery
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• 제44권5호
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• pp.370-377
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• 2017

Background Composite grafts are frequently used for facial reconstruction. However, the unpredictability of the results and difficulties with large defects are disadvantages. Adipose-derived stem cells (ADSCs) express several cytokines, and increase the survival of random flaps and fat grafts owing to their angiogenic potential. Methods This study investigated composite graft survival after ADSC injection. Circular chondrocutaneous composite tissues, 2 cm in diameter, from 15 New Zealand white rabbits were used. Thirty ears were randomly divided into 3 groups. In the experimental groups (1 and 2), ADSCs were subcutaneously injected 7 days and immediately before the operation, respectively. Similarly, phosphate-buffered saline was injected in the control group just before surgery in the same manner as in group 2. In all groups, chondrocutaneous composite tissue was elevated, rotated 90 degrees, and repaired in its original position. Skin flow was assessed using laser Doppler 1, 3, 6, 9, and 12 days after surgery. At 1 and 12 days after surgery, the viable area was assessed using digital photography; the rabbits were euthanized, and immunohistochemical staining for CD31 was performed to assess neovascularization. Results The survival of composite grafts increased significantly with the injection of ADSCs (P<0.05). ADSC injection significantly improved neovascularization based on anti-CD31 immunohistochemical analysis and vascular endothelial growth factor expression (P<0.05) in both group 1 and group 2 compared to the control group. No statistically significant differences in graft survival, anti-CD31 neovascularization, or microcirculation were found between groups 1 and 2. Conclusions Treatment with ADSCs improved the composite graft survival, as confirmed by the survival area and histological evaluation. The differences according to the injection timing were not significant.

• 대한소아치과학회지
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• 제27권2호
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• pp.222-228
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• 2000

Ectodermal dysplasia(외배엽 이형성증)은 외배엽성 기관에 한가지 이상의 선천적 이상소견을 특징으로 하는 질환이다. Ectodermal dysplasia는 약 120종류 이상이 보고되고 있고, 이 중 Hypohidrotic ectodermal dysplasia가 가장 잘 알려져 있으며 이는 성염색체 열성인자에 의해 유전되며 남성에서 호발한다고 한다. 임상증상으로는 무한증, 감모증, 무치증 혹은 핍지증이 가장 특징적이다. 이외에도 무피지종, 손톱이형성증, 가늘고 성긴 머리카락, 두드러진 이마, 안장코, 돌출된 안와상부, 입술의 돌출과 함께 피부가 건조하고 땀샘이 결핍되어 있어서 더위를 참지 못하고 발열이 일어나기 쉽다. 본 증례의 환자는 단국대학교 치과병원 소아치과에 내원한 6세 6개월된 남아로써 무치증을 보이는 Hypohidrotic ectodermal dysplasia로 진단되었고 환자의 심미적 기능적 결함을 해소하기 위해 총의치로 치료를 시행하는 동안 다소의 지견을 얻어 이를 보고하는 바이다.

• Archives of Plastic Surgery
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• 제35권2호
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• pp.169-173
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• 2008

Purpose: Sacrococcygeal pilonidal sinus is a chronic inflammatory disease that mostly affects young people, which warrants surgical intervention. Although many surgical methods have been suggested, an optimal surgical method remains controversial because of high recurrence rates and postoperative complications. The objective of this study is to evaluate the results of wide excision and coverage with fasciocutaneous advancement flap for the treatment of sacrococcygeal pilonidal sinus, and to assess the usefulness of this method Methods: From May 1995 to October 2006, the authors treated 19 patients with the use of coverage with fasciocutaneous flap after wide excision. The results were evaluated regarding recurrence rates, complications, and the change in sensitivity of the gluteal region after surgery. The follow-up period was 7 to 142 months (mean, 76 months). All patients were male. Results: Postoperative complications were wound infection at the suction drain insertion site and skin necrosis around the suture margin in one case, respectively. During the follow up period, only one recurrence (5.3%) was seen in fifth postoperative month, which was successfully treated by the same operative procedure. There was no other complications such as seroma, hematoma, wound dehiscence and flap loss. Extensive scarring and anatomic distortion did not occur in the reconstructed area. In addition, sensitivity of the gluteal region did not diminish. The aesthetic results were satisfactory for all patients as well. Conclusion: The authors advocate that fasciocutaneous flap closure be a good alternative method to cover defects after the excision of sacrococcygeal pilonidal sinus.

• Archives of Plastic Surgery
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• 제43권4호
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• pp.344-351
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• 2016

Background Xeroderma pigmentosum (XP) is an autosomal recessive disorder characterized by xerosis, ultraviolet light sensitivity, and cutaneous dyspigmentation. Due to defects in their DNA repair mechanism, genetic mutations and carcinogenesis inevitably occurs in almost all patients. In these patients, reconstruction of cutaneous malignancies in the head and neck area is associated with some challenges such as likelihood of recurrence and an aggressive clinical course. The aim of this study is to discuss the therapeutic options and challenges commonly seen during the course of treatment. Methods Between 2005 and 2015, 11 XP patients with head and neck cutaneous malignancies were included in this study. Demographic data and treatment options of the patients were evaluated. Results The mean age of the patients was 32 years (range, 10-43) (4 males, 7 females). The most common tumor type and location were squamous cell carcinoma (6 patients) and the orbital region (4 patients), respectively. Free tissue transfer was the most commonly performed surgical intervention (4 patients). The average number of surgical procedures was 5.5 (range, 1-25). Six patients were siblings with each other, 5 patients had local recurrences, and one patient was lost to follow-up. Conclusions Although genetic components of the disease have been elucidated, there is no definitive treatment algorithm. Early surgical intervention and close follow-up are the gold standard modalities due to the tendency toward rapid tumor growth and possible recurrence. Treatment must be individualized for each patient. In addition, the psychological aspect of the disease is an important issue for both patients and families.

• Archives of Plastic Surgery
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• 제36권1호
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• pp.75-79
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• 2009

Purpose: The transverse rectus abdominis musculocutaneous(TRAM) flap is the most commonly used autogenous tissue flap for breast reconstruction. Postoperatively, partial flap loss or fat necrosis are relatively common and it may result in a smaller breast volume with marked contour irregularities. These defects are not easy to reconstruct with local tissue rearrangement or with breast implants. The current authors present the results of 2 patients who underwent Latissimus dorsi(LD) flap reconstruction to correct partial flap or fat necrosis that developed after TRAM flap breast reconstruction. Method: Case1: A 50 - year - old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively partial flap necrosis was developed. Secondary breast reconstruction using LD flap was done. Case2: A 51 - year - old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively fat necrosis was developed. Secondary breast reconstruction using LD flap was done. Results: Secondary breast reconstruction using LD flap survived completely and produce successful reconstruction. There was no significant complication in both patients. Conclusion: LD flap provides sufficient, vascularized skin and soft tissue. The flap can be molded easily to replace deficient tissue in all areas of the breast. These attributes make it an ideal candidate for salvage of the partially failed TRAM flap breast reconstructio.

• Archives of Plastic Surgery
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• 제35권1호
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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.

• Archives of Plastic Surgery
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• 제39권1호
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• pp.55-58
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• 2012

We experienced satisfactory outcomes by synchronously transplanting an artery and vein using an anterolateral thigh flap pedicle between the vascular pedicle and recipient vessel of a flap for scalp reconstruction. A 45-year-old man developed a subdural hemorrhage due to a fall injury. In this patient, the right temporal cranium was missing and the patient had $4{\times}3cm$ and $6{\times}5cm$ scalp defects. We planned a scalp reconstruction using a latissimus dorsi free flap. Intraoperatively, there was a severe injury to the right superficial temporal vessel because of previous neurosurgical operations. A 15 cm long pedicle defect was needed to reach the recipient facial vessels. For the vascular graft, the descending branch of the lateral circumflex femoral artery and two venae comitantes were harvested. The flap survived well and the skin graft was successful with no notable complications. When an interposition graft is needed in the reconstruction of the head and neck region for which mobility is mandatory to a greater extent, a sufficient length of graft from an anterolateral flap pedicle could easily be harvested. Thus, this could contribute to not only resolving the disadvantages of a venous graft but also to successfully performing a vascular anastomosis.