• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.4
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• pp.801-805
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• 2009

This paper reports on a flexible flap valve actuated by electromagnetic force under a constant pressure source. The flexible flap valve consists of the three main components: a flexible flap with a steel disk embedded in PDMS, an electromagnetic actuator and two glass plates with inlet and outlet. The flap valve is fabricated by SU-8 mold process, the EDM process and oxygen plasma treatment. The dimension of an assembled flap valve is $12[mm]{\times}20[mm]{\times}28[mm]$. The stroke volume of the flap valve is measured for various pressures. And the time of the applied input voltage is varied to change the open time of the valve. When the input voltage of 30[V] is applied for 0.25[s], the minimum stroke volume of the flap valve is $40[{\mu}L]$ at 70 [kPa].

• Korean Journal of Head & Neck Oncology
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• v.11 no.1
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• pp.47-55
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• 1995

A large lateral facial defects especially a through and through defect of the cheek remains as challenging field of reconstruction for the head and neck surgeons. Closure of these wounds is technically troublesome due to the magnitude and location of the soft tissue and skin defect, functional and aesthetic consideration. optimal cancer surveillance, and desire for good nourishment. Most traditional methods dealing with these defects, including split-thickness skin graft, local and regional flaps as well as musculocutaneous flaps have their limitations. We applied four different methods for these reconstruction in four cases. We utilized temporal muscle flap, forearm free flap and secondary healing for repair of mucosal defects, and medial base cervicopectoral flap, pectoralis major myocutaneous flap and cervicofacial flap for the reconstruction of external skin defects. In one case, both sides were reconstructed with single forearm free flap. In our experiences, secondary healing could be one of the useful method for mucosal repair in the defect between upper and lower gingivobuccal sulcus. However, forearm free flap was thought to be more ideal for the cases with mandibulectomy. For the external repair, the regional skin flap was considered to be superior to pectoralis major myocutaneous flap or forearm free flap especially on color matching.

• Korean Journal of Head & Neck Oncology
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• v.1 no.1
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• pp.35-61
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• 1985

The surgical treatment of advanced carcinomas and some benign tumors having clinically malignant behaviors of the head and neck region often require extensive resection, necessitating large flaps for reconstruction. Since the original upper arm flap was described by Tagliacozzi in 1597, a variety of technique such as random pattern local flap, axial flap, distant flap, scalping flap, myocutaneous flap, free flap etc. have been proposed for reconstruction of head, face and neck defects. Reconstruction of the facial defects usually require the use of distant tissue. Traditionally, nasal reconstruction has been carried out with a variety of forehead flaps. In recent years, there has been more acceptance of immediate repairs following the removal of these tumors. As a result, patients are more willing to undergo these extensive resections to improve their chances of cure, with the reasonable expectation that an immediate reconstruction will provide an adequate cosmetic result. Authors experienced 13 cases of head and neck tumor during last three and half years that required wide excision and immediate reconstruction with various flaps, not with primary closure or simple skin graft. We present our experience with varied flaps for reconstruction after wide resection of head and neck tumors 3 cases of defect of dorsum of nose or medial canthus with island forehead flaps, lower eyelid defect with cheek flap, cheek defect with Limberg flap, orbital floor defect with Temporalis muscle flap, lateral neck defects with Pectoralis major myocutaneous flap or Latissimus dorsi myocutaneous free flap, subtotal nose defect with scalping flap, wide forehead defect with Dorsalis pedis free flap and 3 cases of mandibular defect or mandibular defect combined with lower lip defect were reconstructed with free vascularized iliac bone graft or free vascularized iliac bone graft concomitantly combined with free groin flap pedicled on deep circumflex iliac vessels We obtained satisfactory results coincided wi th goal of treatment of head and neck tumors, MAXIMAL CURE RATE with MINIMAL MORBIDITY, OPTIMAL FUNCTION, and an APPEARANCE as close to normal as possible.

• Archives of Reconstructive Microsurgery
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• v.15 no.2
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• pp.58-64
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• 2006

Purpose: Management of soft-tissue defect after open tibial fractures includes immediate and repeated debridement, skeletal stabilization, and early soft-tissue coverage with muscle flaps. The purpose of this study was to evaluate the outcome of the free rectus abdominis muscle flap (RA flap) for treatment of open fractures of the tibia and to discuss its advantages compared with the latissimus dorsi muscle flap (LD flap) in poly trauma patients. Materials and Methods: We performed a retrospective review of 5 patients who had a severe (Gustilo IIIb or IIIc) open fracture of the tibia treated with RA flap from May 2003 to March 2006. All were men, and the mean age was 46.6 years (range, $28{\sim}68$). Three patients had combined injuries such as pelvic bone fractures, multiple rib fractures with hemothorax, and contralateral tibial fracture. All patients received RA flap within 7 days after trauma except two with established chronic osteomyelitis. Results: All flaps survived, and there was no marginal flap necrosis. During the follow-up period, there was no evidence of persistent or recurrent osteomyelitis. The size of RA flap ranged from $8{\sim}20\;cm$ in length and $6{\sim}10\;cm$ in width. The average time required for RA flap elevation was 32 minutes, which is shorter than LD flap. Flap elevation could be done in supine position which is essential in poly trauma patients. Conclusion: Although a wide variety of options are available, RA flap is regarded as an optimal method for coverage of soft-tissue defect of the open tibial fracture in poly trauma patients. LD flap is reserved for large sized soft-tissue defect which cannot be covered by RA flap.

• Archives of Plastic Surgery
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• v.37 no.1
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• pp.52-58
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• 2010

Purpose: The digital artery perforator flap was recently introduced and has been proven to be useful for reconstruction of various finger defects. Short operative time, less invasive surgery, and reliable flap circulation are the major advantages of this flap. The authors presented the clinical cases of the digital artery perforator flap and compared them with the distant flaps within a hand (thenar and hypothenar flaps) to reveal their differences. Methods: From May of 2006 to February of 2009, the authors performed reconstructions of finger defects with the digital artery perforator flaps in 10 patients as with the distant flaps within hand in 9 patients (7 thenar and 2 hypothenar flaps). In these two groups of the patients, flap size, use of skin graft, length of stay in hospital, healing time, complications were reviewed retrospectively and compared with statistical analysis (Student's t-test). Results: All flaps survived completely. The mean size of the perforator flap was $0.9{\times}1.9\;cm$ and the mean distant flap within a hand was $1.9{\times}2.0\;cm$. The use of skin graft was reduced in the perforator group because the donor site of the flap was closed primarily. The hospitalization period and healing time also reduced significantly in the perforator group. Minor complications (partial flap loss) were noted in small percentages in both groups but resolved with conservative management. Mean follow-up period was about 6 weeks. Conclusion: The digital artery perforator flap was smaller than the distant flap but its reconstruction of finger defects was reliable and comparable to the conventional distant flaps within a hand. This flap would be not only an alternative method but very useful in the management of various finger defects, because of ease of operative technique, less invasive surgery, decreased need of skin graft, and shorter period of hospitalization and healing time.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.5
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• pp.454-458
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• 2010

Velopharyngeal insufficiency is defined as a status in which nasal cavity and oral cavity can not be sepa-rated when speaking, swallowing by any reason. It has been treated by palatorrhaphy, pharyn-geal flap, local flap, free flap etc. When the size of the defect is small, it can be restored by palatorrhaphy, pharyngeal flap etc. But they are not proper for treatment of the large size of defect. In that case, local flap and free flap are more beneficial. Although large defect can be restored by free flap technique, but it is very complex, time-consuming and may bring about esthetical, functional complications of donor site. Buccinator myomucosal flap is a kind of local flap and reported for the first time by Bozola et al in 1989 and it has become a useful way for reconstruction of large intraoral defect. Authors experienced the use of buccinators myomucosal flap for treating secondary velopharyngeal insufficiency with large soft palate defect and obtained good result. So we report the case with literature reviews.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.187-192
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• 2006

The perforator flaps are based on cutaneous vessels which are originated from a main pedicle and penetrate fascia or muscle to reach the skin. The lateral lower leg is one of the most suitable areas for harvesting perforator flaps because a number of perforator vessels exist. The authors applied peroneal perforator flaps in nine patients. Five flaps were reverse island flaps based on peroneal artery and septocutaneous perforator, and four flaps were free flap based on musculocutaneous perforator only. The recipient site was the posterior ankle in three patients, posterior heel in three patients, lateral malleolus, anterolateral ankle, and foot dorsum in one patient each. The flap size ranged from 5 to 12cm long, from 3 to 5cm wide, and the primary closure of the donor site was possible in most cases. All flaps, except for the flap in two patients in the reverse island flap series, survived completely. 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 superficial skin defects. Also, this flap may be considered as an alternative to radial forearm flap or other perforator flaps.

• Archives of Plastic Surgery
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• v.47 no.4
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• pp.354-359
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• 2020

The medial sural artery perforator (MSAP) flap is a versatile fasciocutaneous flap that has been used successfully in the reconstruction of defects across the body. In specific cases, it may prove superior to more commonly used options (e.g., anterolateral thigh flap and radial forearm free flap). Historically, a disadvantage of the MSAP flap is the relatively small surface area it provides for reconstruction. We recently encountered a patient with extensive pelvic injuries from prior trauma resulting in significant scarring and contracture of the groin, tethering of the penis, and loss of the scrotum and one testicle. The patient was unable to achieve erection from tethering and his remaining testicle had been buried in the thigh. In considering the reconstructive options, he was not a suitable candidate for a thigh-based or forearm-based flap. An extended MSAP flap measuring 25 cm×10 cm was used for resurfacing of the groin and pelvis as well as for the formation of a neoscrotum. This report is the first to document an MSAP flap utilized for simultaneous groin resurfacing and scrotoplasty. Additionally, the dimensions of this flap make it the largest recorded MSAP flap to date.

• Archives of Reconstructive Microsurgery
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• v.25 no.1
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• pp.15-18
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• 2016

Any types of burn injury that involve more than deep dermis often require reconstructive treatment. In gluteal region, V-Y fasciocutaneous advancement flap is frequently used to cover the defect. However, in case of large burn wounds, this kind of flap cannot provide adequate coverage because of the lack of normal surrounding tissues. We suggest V-Y adipofascial flap using the surrounding superficially damaged tissue. We present the case of a patient who was referred for full-thickness burn on gluteal region. We performed serial debridement and applied vacuum-assisted closure device to defective area as wound preparation for coverage. When healthy granulation tissue grew adequately, we covered the defect with surrounding V-Y adipofascial flap and the raw surface of the flap was then covered with split-thickness skin graft. We think the use of subcutaneous fat as an adipofascial flap to cover the deeper defect adjacent to the flap is an excellent alternative especially in huge defect with uneven depth varying from subcutaneous fat to bone exposure in terms of minimal donor site morbidity and reliability of the flap. Even if the flap was not intact, it was reuse of the adjacent tissue of the injured area, so it is relatively safe and applicable.

• Archives of Reconstructive Microsurgery
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• v.24 no.1
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• pp.24-27
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• 2015

During flap elevation, most perforators are cut except one or more perforators that are essential to flap survival. However these cutout perforators can cause deterioration of the blood circulation of the flap. To salvage the jeopardized flaps, rebuilding the perforator system is essential for flap survival. In the first case, after flap elevation, the upper abdominal flap margin was severely ischemic. To supply blood to the upper abdominal flaps, we found and used a major perforator underneath the upper abdominal flap which was cut earlier during the elevation, and we performed reanastomosis with ipsilateral deep inferior epigastric artery. Upper abdominal flap ischemic area was limited to a narrow suture area. In the second case, we performed free superficial inferior epigastric artery (SIEA) flap reconstruction. After successful anastomosis of the SIEA and superficial inferior epigastric vein (SIEV) with internal mammary artery and vein, serious venous congestion occurred immediately because of SIEV malfunction. We found the largest perforator vein under the flap, as an alternate way to drain, then connected it with the thoracoacromial vein with a vein graft harvested in the contralateral SIEV. Circulation has improved. In conclusion, perforator system reconstruction is essential in a jeopardized flap salvage.