Oral and maxillofacial-head and neck reconstruction with soft tissue free flaps of 41 cases: A single team's experience

Objective To retrospectively review the single team's experience of oral and maxillofacialhead and neck reconstruction involving 41 soft tissue free flap procedures.Methods From 1994 to 2012,41 patients who underwent oral and maxillofacial-head and neck soft tissue free flap reconstruction at the Department of Oral and Maxillofacial-Head and Neck Surgical Oncology,Hospital and College of Stomatology,Xi'an Jiaotong University,were reviewed with clinicopathologic data.Results The 41 patients included 24 men and 17 women with a mean age of 54 years.A total of 41 soft tissue free flaps were performed to reconstruct different anatomical structures in the head and neck region including oral mucosa,facial bone,head and neck skin.Two types of soft tissue free flaps were used to reconstruct surgical defects,including radial forearm flap and latissimus dorsi myocutaneous flap.Radial forearm flaps were used for 37cases and latissimus dorsi-myocutaneous flaps were 4 cases.Of 41 cases,39 were successful,with an overall success rate of 95.1%.There were 2 free flap failures,including one radial forearm flap and one latissimus dorsi-myocutaneous flap(partial flap necrosis);hence,the flap success rates for radial forearm flap and latissimus dorsimyocutaneous were,respectively,97.3% and 87.5%.Conclusions Radial forearm flap and latissimus dorsi-myocutaneous flap are reliable soft tissue free flaps to repair oral and maxillofacial-head and neck area with high success rate,which resulted in good functionally and cosmetically with fewer complications both donor and recipient sites.

宽带W波段Flaps天线仿真与设计

设计了一种结合了"十"字和圆环的新型宽带W波段Flaps(Flat Parabolic Surface antenna)天线单元。相比于传统的单层Flaps天线单元,新型单元能获得更宽的相位范围且相移精度更高,能有效拓展天线的带宽。利用这种单元设计了94 GHz的单层Flaps天线,仿真结果显示了较好的带宽性能和方向性,中心频率处增益18.2 dBi,在10.6%的带宽内增益下降小于1 dB,实现了较好的宽带性能,为单层W波段Flaps天线的设计提供了一种新途径。

Distally based perforator sural flaps for foot and ankle reconstruction

Distally based perforator sural flaps from the posterolateral or posteromedial lower leg aspect are initially a neurofasciocutaneous flap that can be transferred reversely to the foot and ankle region with no need to harvest and sacrifice the deep major artery. These flaps are supplied by a perforating artery issued from the deep peroneal artery or the posterior tibial artery, and the chainlinked adipofascial neurovascular axis around the sural/saphenous nerve. It is a versatile and reliable technique for soft-tissue reconstruction of the heel and ankle region with 180-degrees rotation. In this paper, we present its developing history, vascular basis, surgical techniques including flap design and elevation, flap variations in pedicle and component, surgical indications, and illustrative case reports with different perforating vessels as pivot points for foot and ankle coverage.

Omental flaps reduces complications after pancreaticoduodenectomy

BACKGROUND： Major complications after pancreaticoduo- denectomy are usually caused by a leaking pancreaticojejunal anastomosis. Omental flaps around various anastomoses were used to prevent the formation of fistula.

Sensory reinnervation of free flaps in reconstruction of the breast and the upper and lower extremities

There is long-standing debate about sensate versus non-sensate free microvascular flaps among microsurgeons. The principle of connecting not only the vascular supply, but also sensitive nerves, in free tissue transfer is attractive. However, increased operating time and partial spontaneous innervation led to the common decision to restrict microsurgical tissue transfer to the vascular anastomosis and to leave the nerves ＂untreated＂. Nevertheless, in special cases such as breast reconstruction or extremity reconstruction, the question about sensory nerve coaptation of the flaps remains open. We present our experience with free microvascular tissue transfer for breast and extremity reconstruction and compare the data with previous literature and conclude that most free flap surgeries do not benefit from nerve coaptation.

New advances in the mesenchymal stem cells therapy against skin flaps necrosis

Mesenchymal stem cells(MSCs), multipotential cells that reside within the bone marrow, can be induced to differentiate into various cells, such as osteoblasts, adipocytes, chondrocytes, vascular endothelial progenitor cells, and other cell types. MSCs are being widely studied as potential cell therapy agents due to their angiogenic properties, which have been well established by in vitro and in vivo researches. Within this context, MSCs therapy appears to hold substantial promise, particularly in the treatment of conditions involving skin grafts, pedicle flaps, as well as free flaps described in literatures. The purpose of this review is to report the new advances and mechanisms underlying MSCs therapy against skin flaps necrosis.

Free Flow-through Anterolateral Thigh Flaps for Wrist High-tension Electrical Burns:A Retrospective Case Series

Objective The objective of this report was to demonstrate the clinical application of free flow-through anterolateral thigh flaps for the treatment of high-tension electrical wrist burns.Methods We collected the data of 8 patients with high-tension electrical wrist burns admitted to Beijing Jishuitan Hospital from January 2014 to December 2018.The clinical and pathological data were extracted from electronic hospital medical records.We obtained follow-up information through clinic visits.Results The injury sites for all 8 patients were the wrists,specifically 5 right and 3 left wrists,all of which were on the flexor side.Five patients had ulnar artery embolism necrosis and patency,with injury to the radial artery.Two patients had ulnar and radial arterial embolization and necrosis.The last patient had ulnar arterial embolization and necrosis with a normal radial artery.After debridement,the wound area ranged from 12 cm×9 cm to 25 cm×16 cm.The diagnoses for the eight patients were type II to type III high-tension electrical wrist burns.Free flow-through anterolateral thigh flaps(combined with great saphenous vein transplantation if necessary)were used to repair the wounds.The prognosis for all patients was good after six months to one year of follow-up.Conclusion Treating wrist types II and III high-tension electrical burns is still challenging in clinical practice.The use of free flow-through anterolateral thigh flaps(combined with great saphenous vein transplantation if necessary)to repair the wound and to restore the blood supply for the hand at the same time is a good choice for treating severe wrist electrical burns.

Extensive full-thickness eyelid reconstruction with rotation flaps through "subcutaneous tunnel" and palatal mucosal grafts

· AIM: To reconstruct the extensive full-thickness defects of eyelids is a challenge for the plastic surgeon because of their complex anatomy and special functions.This article presents and discusses an improved surgical technique in which the orbicularis oculi myocutaneous flap is rotated through a "subcutaneous tunnel" in conjunction with a palatal mucosal graft employed for lining.·METHODS: Data from 22 eyes with extensive full-thickness eyelid defects from various causes between2009 and 2013 were analyzed in this study. After the different layers of eyelid were separated completely, a temporally based orbicularis oculi myocutaneous flap was designed following fishtail lines and was mobilized,leaving the base of the pedicle intact with a submuscular tissue attachment. The flap was then rotated through a "subcutaneous tunnel" to the defect, and the donor site was closed primarily. Posterior lamellar reconstruction was performed with a mucosal graft harvested from the hard palate.·RESULTS: All the flaps were survived without any healing problems. There was no corneal irritation, flap contraction, or significant donor-site morbidity in the follow-up period. The incision scars were almost invisible.The defects were repaired completely, and the evaluations showed satisfactory function and appearance.·CONCLUSION: This technique is an improved singlestage operation and can be applied to repair large, full-thickness eyelid defects from various causes. With our method, the functional and aesthetic results can be obtained in either the upper or lower eyelids.

Autologous sclera-muscle flaps technique in evisceration with hydroxyapatite implantation

·AIM: To provide superior cosmetic results and reduce complications, unlike traditional evisceration coupled with implant insertion technique and its modifications,we have developed a novel and simple technique for anophthalmic patients.·METHODS: All patients who underwent the scleral-muscle flaps procedure in evisceration with the placement of hydroxyapatite implant were included in the study. Main outcome measures were complications such as exposure, infection, chemosis, conjunctival inclusion cysts, granulomas. Meanwhile, implant motility was indirectly measured and the results were collected and analyzed.· RESULTS: A total of twenty-eight patients were enrolled in the study. Eighteen were men(64.29%) and ten were women(35.71%). Ages ranged from 18 to 65y(mean age, 32 years old). Mean follow-up was 12.32mo(range, 9-16mo). All patients received a hydroxyapatite implant. The average diameter of the implant was 19.29 ±1.36 mm(range, 18-22 mm). Minor complications occurred in 3 patients, and a major complication was observed in 1 patient. Mean motility were 11.04 ±1.45 mm horizontally(range, 7-14 mm) and 8.57 ±1.50 mm vertically(range, 5-12 mm).·CONCLUSION: The sclera-muscle flaps technique in evisceration with hydroxyapatite implantation is simple and practical that eases the surgical procedure, enables a proper size hydroxyapatite implantation, distinctively reduces complications and provides superior surgery results, especially the motility of the implant.

Numerical Analysis of Influence of Gurney Flaps Applied to Wind Turbines

The effect of Gurney flaps with different heights on the S809 airfoil and NH1500 blade is numerically simulated.The influence of the Gurney flap is analyzed at different wind speeds and the comparison of the aerodynamic performance is given between the blades with and without the Gurney flap.The results demonstrate that a Gurney flap added on the blade can greatly increase the efficiency of the wind turbine especially at high wind speeds.

Sternal Reconstruction of Deep Sternal Wound Infections Following Median Sternotomy by Single-stage Muscle Flaps Transposition

Objective To assess clinical effectiveness of using bilateral pectoralis major or plus rectus abdominis muscle flaps in treating deep sternal wound infection(DSWI) following median sternotomy. Methods Between January 2009 and December 2013, 19 patients with DSWI after median sternotomy for cardiac surgery were admitted to our hospital, including 14 males(73.7%) and 5 females(26.3%), aged 55±13(18-78) years. According to the Pairolero classification of infected median sternotomies, 3(15.8%) patients were type II, and the other 16(84.2%) were type III. Surgical procedure consisted of adequate debridement of infected sternum, costal cartilage, granulation, steel wires, suture residues and other foreign substances. Sternal reconstruction used the bilateral pectoralis major or plus rectus abdominis muscle flaps to obliterate dead space. The drainage tubes were placed and connected to a negative pressure generator for adequate drainage. Results There were no intraoperative deaths. In 15 patients(78.9%), bilateral pectoral muscle flaps were mobilized sufficiently to cover and stabilize the defect created by wound debridement. 4 patients(21.0%) needed bilateral pectoral muscle flaps plus rectus abdominis muscle flaps because their pectoralis major muscle flaps could not reach the lowest portion of the wound. 2 patients(10.5%) presented with subcutaneous infection, and 3 patients(15.8%) had hematoma. They recovered following local debridement and medication. 17 patients(89.5%) were examined at follow-up 12 months later, all healed and having stable sternum. No patients showed infection recurrence during the follow-up period over 12 months. Conclusion DSWI following median sternotomy may be effectively managed with adequate debridement of infected tissues and reconstruction with bilateral pectoralis major muscle or plus rectus abdominis muscle flap transposition.

Reconstruction of the thoracic tracheal defects with portions of deepithelialized myocutaneous flaps after resection of a large tumor

Objective： To study the possibility of using portions of deepithelialized myocutaneous flaps to the reconstruction of thoracic tracheal defects after resection of a large tumor. Methods： From June 2007 to June 2012, five cases of defects of the thoracic trachea were reconstructed by applying portions of deepithelialized myocutaneous flaps. The patients were 27-61 years old with 4 male cases and 1 female. The cervical trachea ranged in diameter from 4-8.5 cm with circumferences of approximately 1/3-2/5 of the bronchial circumference. Results： M1 five patients with thoracic tracheal defects after resection of a large tumor were cured of portions of deepithelialized myocutaneous flaps, with no tracheal stricture remaining and vomica successfully eliminated. During the first 1 to 3 months after the operation, bronchoscopy showed that the tracheal lumens were smooth, and the visible skin of the musculocutaneous flaps became gray and exhibited a small amount of white discharge. Conclusions： Despite this being a small series and short follow-up, this thoracic tracheal reconstruction with portions of deepithelialized myocutaneous flaps shows encouraging preliminary results and could be an alternative to other methods for the treatment of carefully selected patients with thoracic tracheal defects.

Aerodynamic improvement of a delta wing in combination with leading edge flaps

Recently, various studies of micro air vehicle （MAV） and unmanned air vehicle （UAV） have been reported from wide range points of view. The aim of this study is to research the aerodynamic improvement of delta wing in low Reynold＇s number region to develop an applicative these air vehicle. As an attractive tool in delta wing, leading edge flap （LEF） is employed to directly modify the strength and structure of vortices originating from the separation point along the leading edge. Various configurations of LEF such as drooping apex flap and upward deflected flap are used in combination to enhance the aerodynamic characteristics in the delta wing. The fluid force measurement by six component toad ceil and particle image velocimetry （PIV） analysis are performed as the experimental method. The relations between the aerodynamic superiority and the vortex behavior around the models are demonstrated.

Comparison of corneal flaps created by Wavelight FS200 and Intralase FS60 femtosecond lasers

AIM：To assess and compare the morphology of corneal flaps created by the Wavelight FS200 and Intralase FS60 femtosecond lasers in laser in situ keratomileusis（LASIK）.METHODS：Four hundred eyes of 200 patients were enrolled in this study and divided into Wavelight FS200 groups（200 eyes） and Intralase FS60 groups（200 eyes）.Fourier-domain optical coherence tomography（RTVue OCT） was used to measure the corneal flap thickness of 36 specified measurements on each flap one week after surgery.Results were used to analyze the regularity,uniformity and accuracy of the two types of LASIK flaps.RESULTS：The mean thickness of corneal flap and central flap was 105.71±4.72 μm and 105.39±4.50 μm in Wavelight FS200 group and 109.78±11.42 μm and 109.15±11.59 μm in Intralase FS60 group,respectively.The flaps made with the Wavelight FS200 femtosecond laser were thinner than those created by the Intralase FS60 femtosecond laser（P=0.000）.Corneal flaps in the 2 groups were uniform and regular,showing an almost planar configuration.But the Wavelight FS200 group has more predictability and uniformity of flap creation.The mean deviation between achieved and attempted flap thickness was smaller in the Wavelight FS200 group than that in the Intralase FS60 group,which were 5.18±3.71 μm and 8.68±7.42 μm respectively.The deviation of more than 20 μm was 0.2% measurements in Wavelight FS200 group and 8.29% measurements in Intralase FS60 group.CONCLUSION：The morphologies of flaps created by Wavelight FS200 are more uniform and thinner than those created by Intralase FS60.

Edaravone Enhances the Viability of Ischemia/reperfusion Flaps

The purpose of the experiment was to study the efficacy of edaravone in enhancing flap viability after ischemia/reperfusion（IR） and its mechanism. Forty-eight adult male SD rats were randomly divided into 3 groups： control group（n=16）, IR group（n=16）, and edaravone-treated IR group（n=16）. An island flap at left lower abdomen（6.0 cm×3.0 cm in size）, fed by the superficial epigastric artery and vein, was created in each rat of all the three groups. The arterial blood flow of flaps in IR group and edaravone-treated IR group was blocked for 10 h, and then the blood perfusion was restored. From 15 min before reperfusion, rats in the edaravone-treated IR group were intraperitoneally injected with edaravone（10 mg/kg）, once every 12 h, for 3 days. Rats in the IR group and control group were intraperitoneally injected with saline, with the same method and frequency as the rats in the edaravone-treated IR group. In IR group and edaravone-treated IR group, samples of flaps were harvested after reperfusion of the flaps for 24 h. In the control group, samples of flaps were harvested 34 h after creation of the flaps. The content of malondialdehyde（MDA） and activity of superoxide dismutase（SOD） were determined, and changes in organizational structure and infiltration of inflammatory cells were observed by hematoxylin-eosin（HE） staining, apoptotic cells of vascular wall were marked by terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling（TUNEL） assay, and the apoptotic rate of cells in vascular wall was calculated. The ultrastructural changes of vascular endothelial cells were observed by transmission electron microscopy（TEM）. Seven days after the operation, we calculated the flap viability of each group, and marked vessels of flaps by immunohistochemical staining for calculating the average number of subcutaneous vessels. The results showed that the content of MDA, the number of multicore inflammatory cells and apoptotic rate of cells in vascular wall in the edaravone-treated IR group were significantly lower than those in the IR group. The activity of SOD, flap viability and average number of subcutaneous vessels in the edaravone-treated IR group were significantly higher than those in the IR group. All the differences were statistically significant. The ultrastructure injury of vascular endothelial cells in the edaravone-treated IR group was slighter than that in IR group. It was concluded that edaravone can significantly enhance IR flap viability and protect flap vessels, which is related to scavenging oxygen free radicals, reducing the consumption of SOD, reducing the extent of lipid peroxidation and inflammation, and protecting functional structure of vessels in the early stages of reperfusion.

Two Crossed Dermal Flaps for Prevention of Bottoming out after Breast Reduction

Introduction: Breast reduction is one of the most prevalent plastic surgery procedures in Syria and the world, bottoming out on the other hand is one of the most happened disadvantages after breast reduction with inferior pedicle technique. Different techniques were used to prevent this deformity after inferior pedicle. In this study we tried to prevent bottoming out by using two crossed dermal flaps suspending the inferior pedicle to the periosteum of the 2nd rib. Methods and materials: 32 patients had breast reduction surgery using inferior pedicle technique at Almowassat University Hospital in Damascus. We divide them into 2 groups, 16 patients each. First group we used crossed dermal flaps with the inferior pedicle and the second group was without these flaps, the dermal flaps had a base on the side of the inferior pedicle base, crossed anterior to it in the middle point between the lower edge of the areola and the IMF and then sutured to the periosteum of the 2nd rib on each side. Results: Preoperatively, the average distance between the inframammary fold and areola was 14.5 cm (range, 11 - 18 cm) in the first group without dermal flaps and 14 cm in the second group with dermal flaps. The average amount of breast parenchymal resection was 790 g (range, 140 - 1600 g). The average distance between the inframammary fold and the lower border of the areola was 8.5 cm (range, 7.5 - 9 cm) on the postoperative first-year measurements in the group with flaps and 10.2 cm (8.6 - 11.4 cm) in the other group. Conclusion: Inferior pedicle suspension using crossed dermal flaps has a real role in preventing bottoming out, without using any allogenic or alloplastic materials, making it one of the considered ways in preventing bottoming after breast reduction.

Macro-micro-anatomy of myocutaneous flaps on the dorsum of foot

Thirty feet of Chinese adult cadavers were dissected under an operativemicroscope to observe the extensor hallucis brevis and extensor digitorum brevisand their vessels and nerves in order to design myocutaneous flaps.It was be-lieved that the lateral tarsal artery and the lateral branch of the deep peronealnerve are the best choice to be included in the pedicle when muscle flaps ormyocutaneous flaps are to be obtained from the dorsum of foot.The size of themuscles may be enlarged both laterally and medially as the clinicalcondition requires.

COMPARISON OF THE EXPERIMENTAL AND COMPUTATIONAL STUDY ON THE EFFECTS OF VORTEX CONTROL BY DEFLECTING FLAPS ON A HIGHLY SWEPT DELTA WING

In order to investigate the effects of vortex control by deflecting flaps on the improvement of the aerodynamics of highly swept wings at large incidence, comparison of the experimental and numerical studies was conducted for a 74° delta wing equipped with an apex flap and leading edge flaps. In the experimental study, flow visualization and force measurement were employed and in the numerical study the pseudo compressibility method was utilized to solve the 3 D incompressible Navier Stokes equations. The flow visualization and numerical simulation show that two vortex systems generated on the apex flap and leading edge flaps interact in the form of mergence, and the downward deflection of the apex flap enhances the strength and delays the breakdown of the prime vortex at large incidence. The comparison of the aerodynamic characteristics illustrates that there are advantageous effects of deflecting flaps downward on the control of vortices.

Risk Factors of Anastomotic Thrombosis in 200 Head and Neck Free Flaps among Asian Patients

Background: Despite excellent results from free flap transfers, postoperative thrombosis does occur and, although infrequent, causes total loss of the flap. We investigate the risk factors of anastomotic thrombosis in head and neck free flaps. Study design, Subjects and Methods: A retrospective analysis was carried out on 200 consecutive free flaps applied to patients who underwent head and neck reconstruction. Multiple logistic regression analysis was conducted to identify risk factors of anastomotic thrombosis, taking into account twelve factors: diabetes, obesity, hypertension, hypertriglyceridemia, proteinuria, age, gender, smoking habit, habitual alcohol intake, previous chemotherapy and radiation, and hypercholesterolemia. Results: Hypertension, female gender, aging, and drinking habit were statistically significant risk factors of postoperative thrombosis. Conclusions: Our data suggest that four factors mentioned above are possible predictors of anastomotic thrombosis in free flaps used for head and neck.