• Archives of Reconstructive Microsurgery
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• 제24권1호
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• pp.32-36
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• 2015

The reconstruction of recurrent pressure sores is challenging due to a limited set of treatment options and a high risk of flap loss. Successful treatment requires scrupulous surgical planning and a multidisciplinary approach. Although the tensor fascia lata flap is regarded as the standard treatment of choice-it provides sufficient tissue bulk for a deep trochanteric sore defect-plastic surgeons must always consider the potential of recurrence and accordingly save the second-best tissues. With the various applications of anterolateral thigh (ALT) flaps in the reconstructive field, we report two cases wherein an alternative technique was applied, whereby pedicled ALT fasciocutaneous island flaps were used to cover recurrent trochanteric pressure sores. The postoperative course was uneventful without any complications. The flap provided a sound aesthetic result without causing a dog-ear formation or damaging the lower-leg contour. This flap was used as an alternative to myocutaneous flaps, as it can cover a large trochanteric defect, recurrence is minimized, and the local musculature and lower-leg contour are preserved.

• Archives of Reconstructive Microsurgery
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• 제24권1호
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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.

• Journal of Communications and Networks
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• 제9권4호
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• pp.490-498
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• 2007

BGP route flap damping(RFD) was anecdotally considered to be a key contributor to the stability of the global Internet inter-domain routing system. However, it was recently shown that RFD can incorrectly suppress for substantially long periods of time relatively stable routes, i.e., routes that only fail occasionally. This phenomenon can be attributed to the complex interaction between BGP path exploration and how the RFD algorithm identifies route flaps. In this paper we identify a distinct characteristic of BGP path exploration following a single network event such as a link or router failure. Based on this characteristic, we distinguish BGP route updates during BGP path exploration from route flaps and propose a novel BGP route flap damping algorithm, RFD+. RFD+ has a number of attractive properties in improving Internet routing stability. In particular, it can correctly suppress persistent route flaps without affecting routes that only fail occasionally. In addition to presenting the new algorithm and analyzing its properties, we also perform simulation studies to illustrate the performance of the algorithm.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제19권3호
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• pp.243-249
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• 1997

The purpose of this study is to describe the clinical availability of a variety of intraoral local flaps in reconstruction of oral soft tissue defects, Forty patients with oral soft tissue defects were treated by tongue, buccinator, palatal, labial, facial artery musculomucosal, buccal fat pad, and masseter muscle crossover flap. Total 43 intraoral flaps were used to reconstruct a variety of intraoral soft tissue defects, such as oronasal fistula, oroantral fistula, traumatic deformities and other. The age of patients ranged from 7 to 72 years, with mean age of 39.6 years. Follow up period ranged from 2 to 66 months, mean follow up period of 21.6 months. There were 9 complications, of which four were partial necrosis, three infections, one total necrosis, and 1 speech problem. Except for total necrosis, most of the recipient sited healed uneventually without severe morbidity. We consider that a variety of intraoral local flaps can be available for reconstruction of small of moderate large intraoral soft tissue defects.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제44권4호
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• pp.191-197
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• 2018

Objectives: The objective of the study was to evaluate the results of nasolabial/extended nasolabial flaps as a modality for treatment of oral submucous fibrosis. Materials and Methods: Eleven patients of Stage III or IVa maximum interincisal opening were selected to be operated. Nasolabial/extended nasolabial flaps were done for both the sides. All of the flaps were done in a single stage and were inferiorly based. A similar flap harvest/surgical technique was utilized for all the cases. Results: The preoperative mouth opening ranged from 5 to 16 mm, with a mean of 10.09 mm. At 6 months the mouth opening ranged from 29 to 39 mm. Some of the complications encountered were poor scar, wisdom tooth traumatising the flap, decreased mouth opening due to non compliance and too much bulk. All of theses were managed satisfactorily. Conclusion: The nasolabial flap is a very reliable flap to restore the function of oral cavity. Important adjuvant measures are habit cessation, lifestyle changes, and aggressive physiotherapy.

• Archives of Plastic Surgery
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• 제45권3호
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• pp.253-258
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• 2018

Background The nasolabial flap is ideal for reconstruction of the nasal alar subunit due to its proximity, color and contour match, and well-placed donor scar. When raised as a random-pattern flap, there is a risk of vascular compromise to the tip with increased flap length and aggressive flap thinning. Surgical delay can greatly improve the chances of tip survival, allowing the harvest of longer flaps with greater reach. Methods We describe our technique of lengthening the nasolabial flap through multiple delay procedures. A bipedicled flap was first raised and then transferred as a unipedicled flap with a 6:1 length-to-width ratio. During the delay process, the flap tip was thinned to the subdermal layer. Results In our case series of seven patients, defects as far as the medial canthal area and contralateral ala were reconstructed successfully with no incidence of tip necrosis or flap loss. The resultant flaps were thin enough to be folded over for the reconstruction of alar rim defects. Conclusions We highlight the success of our surgical technique in creating thin and robust nasolabial flaps for the reconstruction of full-thickness defects around the nose.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.29.1-29.7
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• 2020

Background: Microvascular reconstruction is the treatment of choice after oral cancer ablation surgery. There are few published studies of free flap survival among Korean populations. This study aimed to determine the survival rate after 121 consecutive cases of maxillofacial microvascular reconstruction and to analyze the complications associated with microsurgery. Methods: This study included consecutive patients who underwent microsurgical reconstruction with free flaps, from January 2006 through September 2019, performed by a single surgeon at the oral and maxillofacial surgery department of a tertiary medical center. A total of 121 cases were reviewed retrospectively. The flap survival rate, flap type, radiotherapy history, complications, and treatment results were analyzed. Results: Four different flap types were used for microvascular reconstruction: radial forearm (n = 65), fibula (n = 34), latissimus dorsi (n = 21), and serratus anterior muscle with rib bone free flap (n = 1). Total necrosis of the flap was found in four cases (two latissimus dorsi flaps and two fibular flaps). The free flap survival rate was 97.5%. Nineteen patients received radiotherapy before surgery, and none of them experienced flap failure. The mean operation time was 334 ± 83.1 min, and the mean ischemic time was 48.9 ± 12.7 min. Conclusions: The success rate was reliable and comparable with previous studies. The success rate was not affected by radiation therapy. Free flaps can be safely used even after radiation treatment.

• Advances in aircraft and spacecraft science
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• 제8권1호
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• pp.17-30
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• 2021

This is an investigation for a more electric regional aircraft, considering the ATR 72 aircraft as an example and the electrification of its four double slotted flaps, which were estimated to require an energy of 540 Wh for takeoff and 1780 Wh for landing, with a maximum power requirement of 35.6 kW during landing. An analysis and evaluation of three energy harvesting systems has been carried out, which led to the recommendation of a combination of a piezoelectric and a thermoelectric harvesting system providing 65% and 17%, respectively, of the required energy for the actuators of the four flaps. The remaining energy may be provided by a solar energy harvesting photovoltaic system, which was calculated to have a maximum capacity of 12.8 kWh at maximum solar irradiance. It was estimated that a supercapacitor of 232 kg could provide the energy storage and power required for the four flaps, which proved to be 59% of the required weight of a lithium iron phosphate (LFP) battery while the supercapacitor also constitutes a safer option.

• Archives of Plastic Surgery
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• 제48권1호
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• pp.114-120
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• 2021

Background The pedicled anterolateral thigh (ALT) flap has become more popular for the reconstruction of soft-tissue defects in neighboring areas. Nonetheless, few studies in the literature have explored the use of this flap for trochanteric ulcer reconstruction. The aim of our study is to present the author's experience of utilizing the ALT flap, with a focus on technical elements regarding the flap design and the tunneling method to maximize the reach of the flap. Methods The medical records of patients who received pedicled ALT flaps for the reconstruction of trochanteric pressure sores were retrospectively reviewed. The patients' demographic data, operative details, and postoperative complications were evaluated. Results Between October 2018 and December 2019, 10 consecutive patients (age range, 13-45 years) underwent 11 pedicled ALT myocutaneous flaps for trochanteric pressure sore reconstruction. Each flap was designed around the most distal cutaneous perforator that was included in the proximal third of the skin paddle. The flaps ranged in size from 11×6 to 14×8 cm. The ALT flap was transposed through a lateral subcutaneous tunnel in five patients, while the open tunnel technique was used in six patients. All flaps survived, and no vascular compromise was observed. Conclusions The pedicled ALT flap is a safe and reliable option for reconstructing trochanteric pressure sores. An appropriate flap design and a good choice of the tunneling method are crucial for successful flap transposition.

• Archives of Plastic Surgery
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• 제48권1호
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• pp.133-143
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• 2021

Background Extensive research has been conducted on islet transplantation as a possible cure for diabetes. Islet transplantation in the liver via the portal vein has shown remarkable results, but numerous other recipient sites are currently being investigated. We aimed to show the effectiveness of using a muscle flap as a recipient site for islet transplantation. Methods Islet cells were harvested from 12 isogenic Lewis rats, and then diabetes was induced in another 12 isogenic Lewis rats by streptozotocin injection. In six rats, 3,000 islets were transplanted into gastrocnemius muscle flaps, and in the other six rats, the same number of islets were transplanted into the gastrocnemius muscle. The transplanted islet cell function between the two groups was compared by means of blood glucose tests, glucose tolerance tests, immunohistochemistry, and real-time reverse transcription polymerase chain reaction. Results In the muscle flap group, blood glucose levels significantly decreased after islet transplantation. Blood glucose levels were significantly different between the two groups at 3 weeks after transplantation. The muscle flap group showed nearly normoglycemic results upon the glucose tolerance test, whereas the muscle group was hyperglycemic. Immunohistochemical evaluation showed positive results against insulin and glucagon in biopsies of both groups, and the islet cell density was higher in the muscle flap group. There were no statistically significant differences between the two groups in real-time reverse transcription polymerase chain reaction results. Conclusions Our results suggest that muscle flaps are promising candidates for islet cell transplantation.