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Sample records for bulbocavernosus myocutaneous flaps

  1. Management of osteoradionecrosis of the mandible with myocutaneous flaps

    SciTech Connect

    Baker, S.R.

    1983-12-01

    Involvement of large areas of the mandible or the entire mandible with osteoradionecrosis may result in severe functional disability and cosmetic deformity. The use of a well-vascularized pectoralis major myocutaneous flap from outside the original field of irradiation has been successful in obtaining functional and cosmetic goals. Myocutaneous flaps provide bulk for contour and tissue support, and their rich vascular supply promotes healing of the heavily irradiated soft tissue and bone. Successful bone grafting for mandibular reconstruction may follow control of the osteoradionecrosis.

  2. Pectoralis myocutaneous flap for salvage of necrotic wounds

    SciTech Connect

    Price, J.C.; Davis, R.K.; Koltai, P.J.

    1985-02-01

    The authors have utilized six pectoralis major myocutaneous flaps in attempts to salvage extensive necrotic wounds of the pharynx and neck. The flap was employed in the following situations: massive necrosis of the entire neck skin with both carotid artery systems exposed, radiation necrosis of the neck skin with exposure of carotid artery, dehiscence of gastric pull-up from pharynx with resultant carotid exposure, failed trapezius flap in a radionecrotic oral cavity, and two cases of pharyngocutaneous fistula with extensive soft tissue necrosis. These flaps achieved healing in all cases. One death occurred 3 weeks following complete cutaneous healing secondary to a ruptured carotid pseudoaneurysm. One flap underwent total skin loss but the entirety of the muscle survived and the fistula was successfully closed with the back of the muscle being subsequently skin grafted. One case of dehiscence of the flap from oral mucosa resulted in a minor exposure of mandible with limited osteoradionecrosis controlled by topical means. This flap has performed extremely well in these precarious and difficult situations that previously may not have been salvageable. It has also been effective in abbreviating the required hospitalization and wound care. The authors conclude that the pectoralis myocutaneous flap should be the primary choice for the management of extensive postsurgical wound necrosis.

  3. Paradoxical effects of heme arginate on survival of myocutaneous flaps

    PubMed Central

    Czopek, Alicja; Wigmore, Stephen J.; Kluth, David C.

    2013-01-01

    Ischemia reperfusion injury (IRI) contributes to partial flap and solid organ transplant failure. Heme-oxygenase 1 (HO-1) is an inducible, cytoprotective enzyme which protects against IRI in solid organ transplant models. Heme arginate (HA), a HO-1 inducer, is a promising, translatable, preconditioning agent. This study investigated the effects of preconditioning with HA on the clinical outcome of a myocutaneous IRI model. Forty male Lewis rats were randomized to intravenously receive 1) Control-NaCl, 2) HA, 3) HA and tin mesoporphyrin (SnMP), a HO-1 inhibitor; and 4) SnMP alone. Twenty-four hours later, an in situ transverse rectus abdominis myocutaneous flap was performed under isoflurane anesthesia. Viability of flaps was measured clinically and by laser-Doppler perfusion scanning. In vitro work on human epidermal keratinocytes (HEKa) assessed the effects of HA, SnMP, and the iron chelator desferrioxamine on 1) cytotoxicity, 2) intracellular reactive oxygen species (ROS) concentration, and 3) ROS-mediated DNA damage. In contrast to our hypothesis, HA preconditioning produced over 30% more flap necrosis at 48 h compared with controls (P = 0.02). HA-containing treatments produced significantly worse flap perfusion at all postoperative time points. In vitro work showed that HA is cytotoxic to keratinocytes. This cytotoxicity was independent of HO-1 and was mediated by the generation of ROS by free heme. In contrast to solid organ data, pharmacological preconditioning with HA significantly worsened clinical outcome, thus indicating that this is not a viable approach in free flap research. PMID:24089372

  4. Creative Use of Contralateral Combined Myocutaneous Free Flap for Empyema Cavity.

    PubMed

    Tan, Hannah B; Mohan, Anita T; Coonar, Aman S; Malata, Charles M

    2016-01-01

    Treatment of chronic postpneumonectomy empyema is a reconstructive problem that is always complicated by previous thoracic surgical procedures. Free flaps may be used because they effectively obliterate remaining pleural cavity dead space. Combined muscle free flaps with common vascular pedicles are viable alternatives when single muscle flaps do not possess adequate bulk. This case describes a contralateral combined latissimus dorsi-serratus anterior myocutaneous free flap with anastomoses to thoracodorsal vessels used for correction of chronic empyema. We also describe successful correction of a posterolateral chest wall defect using the adjacent axillary system as a recipient vessel. An accompanying skin paddle also enabled reliable cutaneous coverage of the external defect. PMID:26694302

  5. Xenogeneic acellular dermal matrix in combination with pectoralis major myocutaneous flap reconstructs hypopharynx and cervical esophagus.

    PubMed

    Yin, Danhui; Tang, Qinglai; Wang, Shuang; Li, Shisheng; He, Xiangbo; Liu, Jiajia; Liu, Bingbing; Yang, Mi; Yang, Xinming

    2015-11-01

    The aim of this study was to explore xenogeneic acellular dermal matrix (ADM) in combination with pectoralis major myocutaneous flap in hypopharynx and cervical esophagus reconstruction. A total of five patients were treated with this surgical method to reconstruct hypopharynx and cervical esophagus in Second Xiangya Hospital between January 2012 and April 2013. Four of them had hypopharyngeal carcinoma with laryngeal and cervical esophageal invasion, while the fifth patient with hypopharyngeal cancer had developed scars and atresia after postoperative radiotherapy. The defect length after hypopharyngeal and cervical esophageal resection was 6-8 cm, and was repaired by a combination of ADM and pectoralis major myocutaneous flap by our team. Interestingly, the four patients had primary healing and regained their eating function about 2-3 weeks after surgery, the fifth individual suffered from pharyngeal fistula, but recovered after dressing change about 2 months. Postoperative esophageal barium meals revealed that the pharynx and esophagus were unobstructed in all five patients. Xenogeneic ADM in combination with pectoralis major myocutaneous flap for hypopharynx and cervical esophagus reconstruction is a simple, safe and effective method with fewer complications. Nevertheless, according to the defect length of the cervical esophagus, the patients need to strictly follow the medical advice.

  6. Complications and oncologic outcomes of pedicled transverse rectus abdominis myocutaneous flap in breast cancer patients

    PubMed Central

    Somintara, Ongart; Lertsithichai, Panuwat; Kongdan, Youwanush; Supsamutchai, Chairat; Sukpanich, Rupporn

    2016-01-01

    Background There are several techniques for harvesting the pedicled transverse rectus abdominis myocutaneous (TRAM) flap after mastectomy in breast cancer patients. We examined the whole muscle with partial sheath sparing technique and determined factors associated with its complications and oncological outcomes. Methods We retrospectively reviewed the results of 168 TRAM flaps performed between January 2003 and December 2010, focusing on complications and oncologic outcomes. Results Among the 168 pedicled TRAM flap procedures in 158 patients, flap complications occurred in 34%. Most of the flap complications included some degree of fat necrosis. There was no total flap loss. Flap complications were associated with elderly patients and the presence of major donor site complications. Abdominal bulging and hernia occurred in 12% of patients. The bi-pedicled TRAM flap and higher body mass index (BMI) were significant factors associated with increased donor site complications. Seven patients (4%) developed loco-regional recurrence. Within a median follow-up of 27 months, distant metastasis and death occurred in 6% and 4% of patients, respectively. Conclusions The pedicled TRAM flap using the whole muscle with partial sheath sparing technique in the present study is consistent with the results from previous studies in flap complication rates and oncological outcomes. PMID:27563562

  7. Lateral gastrocnemius myocutaneous flap transposition to the midlateral femur: extending the arc of rotation.

    PubMed

    Agarwal, Rishi Raj; Broder, Kevin; Kulidjian, Anna; Bodor, Richard

    2014-05-01

    We report the successful use of an extended lateral gastrocnemius myocutaneous flap for coverage of the midlateral femur using successive delayed elevations. A 62-year-old man underwent wide resection of a liposarcoma of the right anterior thigh with free flap reconstruction and subsequent radiation therapy 10 years before. Four years later, the patient fractured his irradiated femur and was treated with a retrograde intramedullary nail, which subsequently became infected, causing osteomyelitis of the distal femur, septic arthritis of the knee joint, and nonunion of his pathologic fracture. Although advised by numerous surgeons to undergo above-knee amputation, we offered our motivated patient a multidisciplinary approach to clear his infection and pathology; implanted new orthopedic hardware; performed delayed flap reconstruction; and rehabilitated him back to painless, unassisted ambulation. The extended lateral gastrocnemius myocutaneous flap used provided perfused soft tissues and durable coverage for the patient's exposed orthopedic hardware of the midlateral femur, 14 cm above the joint line of the knee. By using this flap to cover a femur defect well above published heights, our patient avoided amputation after years of worsening incapacitation.

  8. SPLIT rectus abdominis myocutaneous double free flap for extremity reconstruction.

    PubMed

    Nyame, Theodore T; Holzer, Paul W; Helm, Douglas L; Maman, Daniel Y; Winograd, Jonathan M; Cetrulo, Curtis L

    2014-01-01

    A Mathes and Nahai type III muscle, such as the rectus abdominis muscle, can be utilized to cover two separate wounds simultaneously utilizing its dual blood supply thereby minimizing donor site morbidity and operative time. We report a case for treatment of bilateral Gustillo type IIIB lower extremity injuries treated with a single rectus abdominis muscle split into two free flaps, with one based on the deep inferior epigastric vessels and one on the superior epigastric vessels to cover the contralateral wound. In our patient, both lower extremity wounds were covered with muscle flaps from the same donor site in a single operation, salvaging both limbs with progression to unassisted ambulatory status. We show in this case report that the utilization of the vascular anatomy of the rectus muscle allows for division of the flap into two flaps, permitting preservation of the contralateral abdominal wall integrity and coverage of two wounds with a single muscle.

  9. Pectoralis major myocutaneous flap in head and neck reconstruction: An experience in 100 consecutive cases

    PubMed Central

    Tripathi, Mayank; Parshad, Sanjeev; Karwasra, Rajender Kumar; Singh, Virender

    2015-01-01

    Background: The pectoralis major myocutaneous (PMMC) flap has been used as a versatile and reliable flap since its first description by Ariyan in 1979. In India head and neck cancer patients usually present in the advanced stage making PMMC flap a viable option for reconstruction. Although free flap using microvascular technique is the standard of care, its use is limited by the availability of expertise and resources in developing world. The aim of this study is to identify the outcomes associated with PMMC flap reconstruction. Patients and Methods: After ethical approval we retrospectively analyzed 100 PMMC flap at a tertiary care hospital from 2006 to 2013. A total of 137 PMMC flap reconstructions were performed out of which follow-up data of 100 cases were available in our record. Results: A total of 100 patients were reviewed of these 86% were of oral cavity and oropharyngeal lesions, 8% were of hypopharyngeal, 3% were of laryngeal malignancies and 3 cases were of salivary gland tumor. Most tumors (83%) were advanced (T3 or T4 lesion). 95 PMMC flap reconstruction were done as a primary procedure, and 5 were salvage procedure. PMMC flap was used to cover mucosal defect in 84 patients, skin defects in 10 patient and both in 6 patients. Overall flap related complications were 40% with a major complication in 10% and minor complications in 30%. No total flap loss occurred in any patient, major flap occurred in 6% and minor flap loss in 12%. In minor flap loss patients, necrotic changes were mostly limited to skin. Orocutaneous and pharyngocutaneous fistula developed in 12 patients. 10% patients required re-surgery after developing various flap related complications Pleural empyema developed in 3 patients. Other minor complications such as neck skin dehiscence and intra-oral flap dehiscence developed in 26 patients. Conclusion: PMMC flap is a versatile flap with an excellent reach to face oral cavity and neck region. With limited expertise and resources, it is

  10. Etanercept protects myocutaneous flaps from ischaemia reperfusion injury: An experimental study in a rat tram flap model.

    PubMed

    Ersoy, Burak; Çevik, Özge; Çilingir, Özlem Tuğçe

    2016-08-01

    Background Being an inevitable component of free tissue transfer, ischemia-reperfusion injury tends to contribute to flap failure. TNF-α is an important proinflammatory cytokine and a prominent mediator of the ischemia-reperfusion injury. Etanercept, a soluble TNF-α binding protein, has shown anti-inflammatory and anti-apoptotic effects in animal models of renal and myocardial ischemia-reperfusion injury. We have designed an experimental study to investigate the effect of etanercept on myocutaneous ischemia-reperfusion injury on transverse rectus abdominis myocutaneous flap model in rats. Methods Twenty-four male Sprague-Dawley rats were divided into 3 groups: In group 1 (sham), the TRAM flap was raised and sutured back without further intervention. In group 2 (control), the flap was raised and the ischemia-reperfusion protocol was followed. In group 3, etanercept (10 mg/kg, i.v.) was administered 10 minutes before reperfusion. At the end of the reperfusion period, biochemical and histolopathological evaluations were performed on serum and tissue samples. Results In the etanercept group the IMA and 8-OHdG levels (p = 0.005 and p = 0.004, respectively) were found significantly lower, and the GSH and SOD levels (p = 0.01 and p < 0.001, respectively) significantly higher in comparison to the control group. The histopathological analysis has revealed a lower degree of hyalinization, degenerated muscle fibers and nuclear change in the etanercept group compared to the control group. Conclusion The results of our experimental study indicate that etanercept offers protection against ischemia-reperfusion injury in skeletal muscle tissue, enhancing the TRAM flap viability. The ability of etanercept to induce ischemic tolerance suggests that it may be applicable in free-flap surgery. PMID:26950289

  11. Gracilis myocutaneous flap: evaluation of potential risk factors and long-term donor-site morbidity.

    PubMed

    Papadopoulos, Othon; Konofaos, Petros; Georgiou, Panos; Chrisostomidis, Chrisostomos; Tsantoulas, Zacharias; Karypidis, Dimitrios; Kostakis, Alkiviadis

    2011-09-01

    This study reviewed our experience with the gracilis myocutaneous (GMC) flap, potential risk factors for flap necrosis, and long-term morbidity at the donor-site. From 1993 to 2002, 29 GMC flaps were harvested from 27 patients (pedicled n = 21 and free n = 8). The overall incidence of flap necrosis was 13.79% (partial (n = 2) and total (n = 2) necrosis). Flap necrosis was correlated with body mass index >25 (P = 0.022), with smoking (P = 0.04 9) and with radiation therapy at the recipient site (P = 0.020). The long-term morbidity at the donor-site was low, except for scar appearance (17.24%), thigh contour deformity (58.62%), and hypoesthesia (17.24%). Significant age and gender differences were seen for ranking of scar ugliness, with females (P = 0.0061) and younger patients (age ≤55) (P = 0.046) assigned higher values. Significant age differences were seen for ranking of thigh contour deformity, with younger patients assigned higher values (P = 0.0012). In conclusion, patient overweight, smoking, and previous radiation therapy at the recipient site may be the "potential risk factors" for flap necrosis. The long-term morbidity at the donor-site was low, which was in agreement with previous reported studies. A larger series would be the subject of a future study.

  12. Subclavicular Pectoralis Major Myocutaneous Flap for Optimal Reconstruction of Large Orbitozygomatic Defects: A Case Report

    PubMed Central

    Pingarron, Lorena; Ruiz, Julian; Rey, Juan; Maniegas, Lourdes; Roson, Silvia; Martinez, Dolores

    2014-01-01

    Since the introduction of microvascular free flaps, the pectoralis major myocutaneous flap (PMMF) has been relegated to background for most reconstructive surgeons. The objective of this article is to show the advantages of cervicofacial defects reconstruction with PMMF using the subclavicular plane route in a challenging clinical case. An 83-year-old man presented with cutaneous temporomalar lesion with orbital spread. Tumor resection was performed, including 12 × 11 cm skin and subcutaneous tissue, overlying zygomatic and malar bone, and orbital exenteration. Radical parotidectomy and functional neck dissection were performed. PMMF was chosen as reconstructive option routing the pedicle to the subclavicular plane. The length of the pedicle was 31 cm. The subclavicular route for PMMF increases the flap's length and arc of rotation compared with the conventional supraclavicular one. This procedure decreases the bulk of the PMMF pedicle which makes it functionally and cosmetically favorable. By using this modification, we may widen the “safe” reconstructive possibilities. PMID:25136415

  13. Reconstruction of complex oro-facial defects using the myocutaneous sub-mental artery flap.

    PubMed

    Saleh, D B; Fourie, L; Mizen, K D

    2014-07-01

    Oro-facial defects require reconstruction that provides suitable colour match and texture. Moreover inner and outer cheek lining and bulk are key considerations. In cases of severe oro-facial infections concomitant mandibular abnormality, for example trismus, can mandate the need for tissue to obturate mandibular defects. We assessed the use of the myocutaneous sub-mental artery flap (MSA) in non-oncological patients with such defects. Twenty two consecutive patients were included in this case series. All patients were survivors of Cancrum Oris (NOMA). Demographic details, nutritional status and co-morbidities were recorded. Defects were classified according to the tissues destroyed; cheek, mandible, oral cavity, lip(s), nose and eye(s). Simultaneous procedures carried out were recorded. The surgical anatomy of the MSA is described. All patients had composite defects of the cheek and oral cavity plus another local anatomical structure. Adjunct procedures such as trismus release were carried out in 18/22 patients. Four patients required a return to theatre. There was no trismus recurrence observed. No flap losses were incurred. The MSA is a robust flap with minimal incidence of major complications. The MSA negates the need for microsurgical tissue transfer. Furthermore the MSA provides adequate bulk to obturate these defects. Future applications of the MSA may include complex oro-facial oncological defects. PMID:24209385

  14. [Temperature determination of the skin surface for the estimation of blood supply disorders in myocutaneous island flaps of rats].

    PubMed

    Herrberger, U; Tilgner, A; Schumann, D

    1989-01-01

    In rectus abdominis myocutaneous island flaps (3.0 x 1.5 cm) of rats (Uje:WIST) skin surface temperature was measured by an infrared pyrometer for monitoring flap viability following experimentally induced blood flow insufficiency. The insufficiency was caused by ligation of the pedicle vessels (epigastric superior artery and vein) on the 3rd, 4th, 5th and 7th d after flap replantation, and by occlusion of these vessels with microclips for 2 h. Only the temperature differences between the intact and the operated skin surface were used to estimate blood flow efficiency not, the absolute values. These differences were statistically insignificant between the intact right and left abdominal skin areas and between the intact skin and the vital flap surfaces. In these cases the maximal temperature differences were 0.52 degree C. Only during the early postoperative period (3-days ligation group) a correlation between blood flow insufficiency and flap viability is expressed by temperature differences (2.14 degrees C). Later on (7-days ligation group) a temperature difference of 1.87 degrees C was no evidence of disturbed wound healing. Thus in advanced stages in myocutaneous flaps differences of blood flow and neovascularization respectively cannot be estimated reliably by measurements of skin surface temperature. However, temperature differences greater than 2 degrees C signal impaired flap viability. PMID:2711783

  15. Vertical rectus abdominis myocutaneous flap for vaginal reconstruction after radical pelvic surgery for Stage II vaginal carcinoma.

    PubMed

    Tapisiz, O L; Gungor, T; Demiralp, C O; Demirseren, M E; Yalcin, H; Mollamahmutoglu, L

    2011-01-01

    Primary carcinomas of the vagina are uncommon, occurring only 2-3% of all gynecological malignancies. In women with early stage of disease, primary surgery, consisting of radical vaginectomy (plus hysterectomy in patients with tumors involving the upper vagina) and systematic dissection of lymphatic drainage of tumor, is a valid option. In these patients, a rectus abdominis myocutaneous (RAM) flap may be favorably used for vaginal reconstruction during radical pelvic surgery. Here we describe a case of Stage II vaginal carcinoma treated with radical pelvic surgery and vertical-RAM (V-RAM) flap reconstruction.

  16. Oncoplastic breast surgery with latissimus dorsi myocutaneous flap for large defect in patients with ptotic breasts: is it feasible when combined with local flaps?

    PubMed Central

    2014-01-01

    Background The latissimus dorsi myocutaneous flap (LDMCF) is frequently applied to breast cancer patients for breast reconstruction. However, the LDMCF is considered inappropriate for patients with ptotic breast. The authors investigated combining LDMCF and two local flaps for large defects of the breast after partial mastectomy in patients with ptosis. Methods Nineteen patients with breast cancer underwent a partial mastectomy with immediate reconstruction. Reconstruction methods consisted of LDMCF, thoraco-epigastric flap, and inferior pedicled rotational local flap, referred to as a combined pedicle flap. The cosmetic results were self-assessed after chemotherapy and radiotherapy by a four-point scoring system. Results Ptosis was graded as follows: two patients with grade 1, 10 patients with grade 2, and seven patients with grade 3. The mean tumor size was 2.7 cm and multifocality was identified in 11 patients (57.9%). The mean excised volume was 468.5 cm3 and the percentage of excised volume was 46.2%. The cosmetic results were excellent in five patients, good in seven patients, fair in six patients, and poor in one patient. Conclusion The combined pedicle flap, consisting of LDMCF, thoraco-epigastric flap, and inferior pedicled rotational local flap, allows good cosmesis in breast cancer patients with large breasts or ptosis despite a wide excision. PMID:24669908

  17. Reconstruction of transhumeral amputation stumps with ipsilateral pedicled latissimus dorsi myocutaneous flap in high voltage electrical burns.

    PubMed

    Kesiktas, Erol; Eser, Cengiz; Gencel, Eyuphan; Aslaner, Emrah Efe; Yavuz, Metin

    2015-03-01

    Injury due to high-voltage (>1000V) electricity is one of the most challenging problems in emergency medicine and plastic surgery. Extremity amputation because of electrical injury yields a stump that leaves vital structures, such as bone, muscle, blood vessels, and nerves, exposed; these structures should be covered with appropriate tissue. We designed a retrospective study that included twelve patients with a high-voltage electrical injury followed by trans-humeral amputation who were evaluated between 2004 and 2013. The ages of the patients ranged between 8 and 35 years (mean, 16.9 years). Following amputation, the defects were covered with an ipsilateral pedicled latissimus dorsi (LD) myocutaneous flap for stump protection and functional transfer. We concluded that the use of an ipsilateral LD myocutaneous flap is an adequate surgical operation in upper extremity amputations resulting from high-voltage electrical burn injuries and that this procedure permits stump length maintenance, contributes to arm functioning, avoids extended operation times, and prepares patients for prosthesis usage.

  18. Surgical resection of invasive adenoid cystic carcinoma of the lacrimal gland and wound closure using a vertical rectus abdominis myocutaneous free flap.

    PubMed

    Andrade, João Paulo; Figueiredo, Sergio; Matias, Julio; Almeida, Ana Catarina

    2016-01-01

    A 64-year-old man presented with a 3-month history of recurrent conjunctivitis. He was evaluated by an ophthalmologist and submitted to a CT scan that revealed an intraconic mass with invasion of the lateral orbital wall. He was operated, the mass was completely removed (with preservation of the intraorbital structures) and the lateral orbital wall rebuilt. The histopathological analysis revealed an adenoid cystic carcinoma of the lacrimal gland. 4 months later a painful recurrence of the lesion was diagnosed with invasion of the orbital roof and eyelids. After a multidisciplinary discussion and request from the patient, an exenteration of the orbit and removal of the lateral and superior orbital wall and dura mater was performed with the objective of a total resection. The wound and orbit were closed with a vertical rectus abdominis myocutaneous free flap to ensure closure. PMID:27646316

  19. Initial experience with the use of porcine acellular dermal matrix (Strattice) for abdominal wall reinforcement after transverse rectus abdominis myocutaneous flap breast reconstruction.

    PubMed

    Cicilioni, Orlando; Araujo, Gerson; Mimbs, Nancy; Cox, Matthew D

    2012-03-01

    Reestablishing anterior rectus fascial integrity remains a clinical challenge after transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction. The main concerns include herniation and bulging due to abdominal weakness. Mesh-assisted closure of the fascial defect has improved bulging and herniation rates but infection, extrusion, and encapsulation are serious concerns with mesh use. Biologic tissue matrices may overcome some of these mesh-related complications. The initial experience of using Strattice for fascial closure after TRAM flap procedure is described in this article. Strattice was in-lain and sutured between the anterior and posterior layers of the rectus fascia, at the rectus muscle donor site. The abdominal wall was closed with progressive tension sutures. Postoperative complications at the donor site were assessed. A total of 16 unilateral and 9 bilateral reconstructions were performed in 25 patients. Length of hospital stay was 2 to 3 days which is shorter than with mesh repair (typically 4-5 days). During a mean follow-up period of 14.0 months, complications occurred in 7 patients (28%): seroma formation (2), minor skin separation (2), superficial skin infection (2), and superficial wound dehiscence (1). Complications were not directly related to Strattice and all, except one (superficial skin infection), were resolved without surgical intervention. In all patients, routine abdominal functions were restored 4 months postoperatively. Strattice is a safe, alternative option to synthetic mesh for fascial repair following TRAM flap breast reconstruction. When used in conjunction with progressive tension suture closure of the abdominal wall, dynamic reconstruction of the abdominal wall with resumption of abdominal function is possible with Strattice.

  20. A comparison between the pectoralis major myocutaneous flap and the free anterolateral thigh perforator flap for reconstruction in head and neck cancer patients: assessment of the quality of life.

    PubMed

    Zhang, Xu; Li, Meng-Jie; Fang, Qi-Gen; Sun, Chang-Fu

    2014-05-01

    Our study investigated the quality of life (QoL) of Chinese patients after immediate reconstruction surgery on individuals with head and neck cancer. In addition, we compared the differences between pectoralis major myocutaneous flap (PMMF) and anterolateral thigh free flap (ALTFF). The University of Washington Quality of Life questionnaire, version 4, was used to assess the QoL. Assessments were performed at least 24 months postoperatively. A total of 110 patients' records were obtained. Among them, 86 patients completed a QoL questionnaire (78.2%). No significant differences could be found in age, primary site, T stage, N stage, and postoperative radiotherapy between PMMF and ALTFF groups. However, there were significant differences between both groups in sex, operation time, and complication. A matched analysis was performed to compare the differences in QoL between patients with head and neck cancers reconstructed with PMMF or ALTFF. Patients reconstructed with ALTFF had better shoulder but worse speech functions. There was a significant effect on the QoL of head and neck cancer patients who had undergone either PMMF or ALTFF reconstruction. The result of this study provide useful information for physicians and patients during their discussion of treatment modalities for head and neck cancers.

  1. Myocutaneous revascularization following graded ischemia in lean and obese mice

    PubMed Central

    Clark, Ross M; Coffman, Brittany; McGuire, Paul G; Howdieshell, Thomas R

    2016-01-01

    Background Murine models of diabetes and obesity have provided insight into the pathogenesis of impaired epithelialization of excisional skin wounds. However, knowledge of postischemic myocutaneous revascularization in these models is limited. Materials and methods A myocutaneous flap was created on the dorsum of wild type (C57BL/6), genetically obese and diabetic (ob/ob, db/db), complementary heterozygous (ob+/ob−, db+/db−), and diet-induced obese (DIO) mice (n=48 total; five operative mice per strain and three unoperated mice per strain as controls). Flap perfusion was documented by laser speckle contrast imaging. Local gene expression in control and postoperative flap tissue specimens was determined by quantitative reverse transcription polymerase chain reaction (RT-PCR). Image analysis of immunochemically stained histologic sections confirmed microvascular density and macrophage presence. Results Day 10 planimetric analysis revealed mean flap surface area necrosis values of 10.8%, 12.9%, 9.9%, 0.4%, 1.4%, and 23.0% for wild type, db+/db−, ob+/ob−, db/db, ob/ob, and DIO flaps, respectively. Over 10 days, laser speckle imaging documented increased perfusion at all time points with revascularization to supranormal perfusion in db/db and ob/ob flaps. In contrast, wild type, heterozygous, and DIO flaps displayed expected graded ischemia with failure of perfusion to return to baseline values. RT-PCR demonstrated statistically significant differences in angiogenic gene expression between lean and obese mice at baseline (unoperated) and at day 10. Conclusion Unexpected increased baseline skin perfusion and augmented myocutaneous revascularization accompanied by a control proangiogenic transcriptional signature in genetically obese mice compared to DIO and lean mice are reported. In future research, laser speckle imaging has been planned to be utilized in order to correlate spatiotemporal wound reperfusion with changes in cell recruitment and gene expression to

  2. Keyhole Flap Nipple Reconstruction.

    PubMed

    Chen, Joseph I; Cash, Camille G; Iman, Al-Haj; Spiegel, Aldona J; Cronin, Ernest D

    2016-05-01

    Nipple-areola reconstruction is often one of the final but most challenging aspects of breast reconstruction. However, it is an integral and important component of breast reconstruction because it transforms the mound into a breast. We performed 133 nipple-areola reconstructions during a period of 4 years. Of these reconstructions, 76 of 133 nipple-areola complexes were reconstructed using the keyhole flap technique. The tissue used for the keyhole dermoadipose flap technique include transverse rectus abdominus myocutaneous flaps (60/76), latissimus dorsi flaps (15/76), or mastectomy skin flaps after tissue expanders (1/76). The average patient follow-up was 17 months. The design of the flap is based on a keyhole configuration. The base of the flap determines the width of the future nipple, whereas the length of the flap determines the projection. We try to match the projection of the contralateral nipple if present. The keyhole flap is simple to construct yet reliable. It provides good symmetry and projection and avoids the creation of new scars. The areola is then tattooed approximately 3 months after the nipple reconstruction. PMID:27579228

  3. Free anterolateral thigh flap harvesting from paralytic limbs in post-polio syndrome

    PubMed Central

    Changchien, Chih-Hsuan; Chen, Wei-Chen; Su, Yu-Min

    2016-01-01

    Abstract We report two cases of poliomyelitis in which an anterolateral thigh myocutaneous free flap was harvested from the paralytic limb for oral reconstruction. We observed a decrease in the pedicle diameter of the anterolateral thigh flap, but the blood supply to the skin paddle was adequate. PMID:27583272

  4. Comprehensive Evaluation of Risk Factors and Management of Impending Flap Loss in 2138 Breast Free Flaps.

    PubMed

    Chang, Edward I; Chang, Eric I; Soto-Miranda, Miguel A; Zhang, Hong; Nosrati, Naveed; Crosby, Melissa A; Reece, Gregory P; Robb, Geoffrey L; Chang, David W

    2016-01-01

    Loss of a breast free flap is a relatively rare but catastrophic occurrence. Our study aims to identify risk factors for flap loss and to assess whether different salvage techniques affect flap salvage. We performed a retrospective review of all breast free flaps performed at a single institution from 2000 to 2010. Overall, 2138 flaps were performed in 1608 patients (unilateral, 1120 and bilateral, 488) with 44 flap losses (2.1%). Age, body mass index, smoking, radiation, chemotherapy, and surgeon experience did not affect flap loss. Abdominal flaps based on a single perforator were at significantly higher risk for flap loss compared with flaps based on multiple perforators (P = 0.0007). Subgroup analysis of the subset of 166 compromised free flaps (flaps requiring a return to the operating room, an intraoperative anastomotic revision, or loss/partial loss of a free flap) demonstrated deep inferior epigastric perforator, and other flaps (superficial inferior epigastric artery and superior gluteal artery perforator) were significantly associated with flap loss [odds ratio (OR) 5.20; P = 0.03 and OR 6.91; P = 0.0004, respectively] compared with transverse rectus abdominis myocutaneous and muscle-sparing transverse rectus abdominis myocutaneous flaps. Although an intraoperative complication was not associated with a flap loss, the need for a reoperation was strongly predictive (P < 0.0001). Flap salvage was the highest within the first 24 hours (83.7%) and significantly less between days 1 and 3 (38.6%; P < 0.0001) and beyond 4 days (29.4%; P < 0.0001). Longer ischemia time was significantly associated with flap loss (P = 0.04). Salvage techniques (aspirin, heparinzation, thrombectomy, and thrombolytic) had no impact on flap salvage rates. Heparinization and thrombolytics were associated with higher loss rates (OR 3.40; P = 0.003 and OR 10.36; P < 0.0001, respectively). Free flap loss following breast reconstruction is multifactorial with higher losses in superficial

  5. Anterolateral thigh fasciocutaneous flap in the difficult perineogenital reconstruction.

    PubMed

    Luo, S; Raffoul, W; Piaget, F; Egloff, D V

    2000-01-01

    A pedicled anterolateral thigh fasciocutaneous flap that was used to cover a complicated perineogenital defect after bilateral gracilis myocutaneous flap for perineal reconstruction is presented. The indications and advantages of this approach are outlined. This technique offers to the plastic surgeon and gynecologic oncologist a new option in the armamentarium for reconstruction of the perineum, and it offers the patient reduced donor-site morbidity. PMID:10626987

  6. Differences in blood flow volume and vascular resistance between free flaps: assessment in 58 cases.

    PubMed

    Takanari, Keisuke; Kamei, Yuzuru; Toriyama, Kazuhiro; Yagi, Shunjiro; Torii, Shuhei

    2009-01-01

    In free-flap transfer, blood flow in the transferred flap contributes to wound healing and to resistance against infection in the recipient site. Successful reconstructions using free tissue transfers may be required to define and choose flaps with abundant blood flow in necessary cases. We investigated blood flow in the flap by transit-time ultrasound flowmeter in 58 free-flap transfers. Flow volume was compared between flap tissues as vascular resistance in the flap was calculated. Fasciocutaneous and osteocutaneous flaps had relatively low blood flow volume, myocutaneous flaps had more, and intraperitoneal flaps had still higher blood flow volume. These differences were statistically significant. Vascular resistance significantly decreased in the same order of comparison. Our findings will help in selecting the most suitable flaps for reconstructive surgery. PMID:18942044

  7. Reconstruction of the chin using an expanded deltopectoral flap following multiple recurrences of oral cancer.

    PubMed

    Balakrishnan, Chenicheri; Hackenson, David; Balakrishnan, Anila; Elliott, David; Careaga, Daniel

    2012-01-01

    An important alternative to free tissue transfer in patients requiring correction of soft tissue chin defects are local and regional flaps, such as the pectoralis major myocutaneous flap and deltopectoral flap. With predictable vascular supply, potential for large size, and good aesthetic match for facial and cervical skin, the deltopectoral flap can offer the reconstructive surgeon additional options in patients who lack vessels suitable for free tissue transfer. The use of an expanded deltopectoral flap for a staged reconstruction of the chin in a patient with cancer recurrences, concomitant resections, radiation and multiple reconstructions is reported.

  8. Reconstruction of the chin using an expanded deltopectoral flap following multiple recurrences of oral cancer.

    PubMed

    Balakrishnan, Chenicheri; Hackenson, David; Balakrishnan, Anila; Elliott, David; Careaga, Daniel

    2012-01-01

    An important alternative to free tissue transfer in patients requiring correction of soft tissue chin defects are local and regional flaps, such as the pectoralis major myocutaneous flap and deltopectoral flap. With predictable vascular supply, potential for large size, and good aesthetic match for facial and cervical skin, the deltopectoral flap can offer the reconstructive surgeon additional options in patients who lack vessels suitable for free tissue transfer. The use of an expanded deltopectoral flap for a staged reconstruction of the chin in a patient with cancer recurrences, concomitant resections, radiation and multiple reconstructions is reported. PMID:23997595

  9. Nonmyocytic Androgen Receptor Regulates the Sexually Dimorphic Development of the Embryonic Bulbocavernosus Muscle

    PubMed Central

    Ipulan, Lerrie Ann; Suzuki, Kentaro; Sakamoto, Yuki; Murashima, Aki; Imai, Yuuki; Omori, Akiko; Nakagata, Naomi; Nishinakamura, Ryuichi; Valasek, Petr

    2014-01-01

    The bulbocavernosus (BC) is a sexually dimorphic muscle observed only in males. Androgen receptor knockout mouse studies show the loss of BC formation. This suggests that androgen signaling plays a vital role in its development. Androgen has been known to induce muscle hypertrophy through satellite cell activation and myonuclei accretion during muscle regeneration and growth. Whether the same mechanism is present during embryonic development is not yet elucidated. To identify the mechanism of sexual dimorphism during BC development, the timing of morphological differences was first established. It was revealed that the BC was morphologically different between male and female mice at embryonic day (E) 16.5. Differences in the myogenic process were detected at E15.5. The male BC possesses a higher number of proliferating undifferentiated myoblasts. To identify the role of androgen signaling in this process, muscle-specific androgen receptor (AR) mutation was introduced, which resulted in no observable phenotypes. Hence, the expression of AR in the BC was examined and found that the AR did not colocalize with any muscle markers such as Myogenic differentiation 1, Myogenin, and paired box transcription factor 7. It was revealed that the mesenchyme surrounding the BC expressed AR and the BC started to express AR at E15.5. AR mutation on the nonmyocytic cells using spalt-like transcription factor 1 (Sall1) Cre driver mouse was performed, which resulted in defective BC formation. It was revealed that the number of proliferating undifferentiated myoblasts was reduced in the Sall1 Cre:ARL−/Y mutant embryos, and the adult mutants were devoid of BC. The transition of myoblasts from proliferation to differentiation is mediated by cyclin-dependent kinase inhibitors. An increased expression of p21 was observed in the BC myoblast of the Sall1 Cre:ARL−/Y mutant and wild-type female. Altogether this study suggests that the nonmyocytic AR may paracrinely regulate the

  10. Nonmyocytic androgen receptor regulates the sexually dimorphic development of the embryonic bulbocavernosus muscle.

    PubMed

    Ipulan, Lerrie Ann; Suzuki, Kentaro; Sakamoto, Yuki; Murashima, Aki; Imai, Yuuki; Omori, Akiko; Nakagata, Naomi; Nishinakamura, Ryuichi; Valasek, Petr; Yamada, Gen

    2014-07-01

    The bulbocavernosus (BC) is a sexually dimorphic muscle observed only in males. Androgen receptor knockout mouse studies show the loss of BC formation. This suggests that androgen signaling plays a vital role in its development. Androgen has been known to induce muscle hypertrophy through satellite cell activation and myonuclei accretion during muscle regeneration and growth. Whether the same mechanism is present during embryonic development is not yet elucidated. To identify the mechanism of sexual dimorphism during BC development, the timing of morphological differences was first established. It was revealed that the BC was morphologically different between male and female mice at embryonic day (E) 16.5. Differences in the myogenic process were detected at E15.5. The male BC possesses a higher number of proliferating undifferentiated myoblasts. To identify the role of androgen signaling in this process, muscle-specific androgen receptor (AR) mutation was introduced, which resulted in no observable phenotypes. Hence, the expression of AR in the BC was examined and found that the AR did not colocalize with any muscle markers such as Myogenic differentiation 1, Myogenin, and paired box transcription factor 7. It was revealed that the mesenchyme surrounding the BC expressed AR and the BC started to express AR at E15.5. AR mutation on the nonmyocytic cells using spalt-like transcription factor 1 (Sall1) Cre driver mouse was performed, which resulted in defective BC formation. It was revealed that the number of proliferating undifferentiated myoblasts was reduced in the Sall1 Cre:AR(L-/Y) mutant embryos, and the adult mutants were devoid of BC. The transition of myoblasts from proliferation to differentiation is mediated by cyclin-dependent kinase inhibitors. An increased expression of p21 was observed in the BC myoblast of the Sall1 Cre:AR(L-/Y) mutant and wild-type female. Altogether this study suggests that the nonmyocytic AR may paracrinely regulate the

  11. [Large abdominal wall reconstruction by free flap after recurrence of a dermatofibrosarcoma protuberans].

    PubMed

    Le Fourn, B; Lejeune, F; Sartre, J Y; Loirat, Y; Pannier, M

    1996-12-01

    Based on a case of recurrence of a dermatofibrosarcoma protuberans of the abdominal wall, the authors discuss the need for initial wide resection of this type of skin tumour and the possibilities of repair of extensive full thickness defects of the abdominal wall by means of a latissimus dorsi myocutaneous free flap.

  12. Doppler-assisted vascular pedicle flaps in eyelid and periorbital reconstruction.

    PubMed

    Yeatts, R P; Newsom, R W; Matthews, B L

    1996-09-01

    The use of a transcutaneous ultrasonic Doppler flow detector to identify the supratrochlear and superficial temporal arteries permits the design of narrow-based, thin-tipped forehead flaps for use in medial canthal and eyelid reconstruction. In the 13 cases described, the axial, vascular supply of a proposed myocutaneous forehead flap was determined with a transcutaneous ultrasonic Doppler flow detector permitting narrow-based pedicle widths of 0.8 to 1.2 cm. The design of the distal portion of the flap was determined by the primary defect. The width of the flap varied from 1.5 to 4.0 cm, with the flap's axial length limited only by the hairline. This use of the ultrasonic Doppler flow detector, permitting narrow-based, thin-tipped vascular pedicle flaps, has assisted in refining the concept of forehead flaps and has made these flaps an acceptable primary reconstructive technique in the periorbital region. PMID:8790111

  13. Algorithmic approach to lower abdominal, perineal, and groin reconstruction using anterolateral thigh flaps.

    PubMed

    Zelken, Jonathan A; AlDeek, Nidal F; Hsu, Chung-Chen; Chang, Nai-Jen; Lin, Chih-Hung; Lin, Cheng-Hung

    2016-02-01

    Lower abdominal, perineal, and groin (LAPG) reconstruction may be performed in a single stage. Anterolateral thigh (ALT) flaps are preferred here and taken as fasciocutaneous (ALT-FC), myocutaneous (ALT-MC), or vastus lateralis myocutaneous (VL-MC) flaps. We aim to present the results of reconstruction from a series of patients and guide flap selection with an algorithmic approach to LAPG reconstruction that optimizes outcomes and minimizes morbidity. Lower abdomen, groin, perineum, vulva, vagina, scrotum, and bladder wounds reconstructed in 22 patients using ALT flaps between 2000 and 2013 were retrospectively studied. Five ALT-FC, eight ALT-MC, and nine VL-MC flaps were performed. All flaps survived. Venous congestion occurred in three VL-MC flaps from mechanical cause. Wound infection occurred in six cases. Urinary leak occurred in three cases of bladder reconstruction. One patient died from congestive heart failure. The ALT flap is time tested and dependably addresses most LAPG defects; flap variations are suited for niche defects. We propose a novel algorithm to guide reconstructive decision-making.

  14. The infrahyoid flap: a comprehensive review of an often overlooked reconstructive method.

    PubMed

    Deganello, Alberto; Leemans, C René

    2014-08-01

    The infrahyoid flap is a myocutaneous pedicled flap mainly nourished by the superior thyroid vessels through the perforators of the infrahyoid muscles. This thin and pliable flap provides a skin island of about 7 by 4 cm from the central part of the anterior neck. The flap can be transferred on its pedicle of superior thyroid artery and vein to reconstruct medium sized head and neck defects created after cancer ablation. We have successfully used this flap in a series of 40 cases with no total flap loss and with 1 case of superficial skin necrosis. The aim of this review is to highlight the clinical usefulness of this pedicled flap even in the microvascular free flap era. A comprehensive review of the available literature reporting on the infrahyoid flap has been carried out using a web search. The history of the infrahyoid flap, the surgical technique with technical innovations, the clinical utility and limitations of this flap, are reported and discussed. Among the 7 larger series (cohort larger than 50 cases) a total of 956 flaps were performed, and the global success rate was 91.7%, with failures being mainly related to partial skin necrosis, as the rate of total (skin and muscle) flap necrosis was only 1%. This flap is reliable, easy to harvest during neck dissection, oncologically safe, it does carry a negligible donor site morbidity. This paper highlights how the infrahyoid flap can represent an excellent reconstructive solution in selected patients and head and neck sites. PMID:24856306

  15. VRAM-pedicled island flap for the coverage of an exposed prosthetic vascular graft in the suprapubic area.

    PubMed

    Rubino, C; Faenza, M; Campitiello, N; Fornino, G; Santanelli di Pompeo, F; Accarino, G C

    2016-01-01

    The exposure of prosthetic vascular graft is a dangerous complication in revascularization procedures. In this case report, we describe a successful coverage of an exposed prosthetic femorofemoral vascular graft in the suprapubic area, with a vertical rectus abdominis myocutaneous (VRAM) island flap. PMID:27583274

  16. VRAM-pedicled island flap for the coverage of an exposed prosthetic vascular graft in the suprapubic area

    PubMed Central

    Rubino, C.; Faenza, M.; Campitiello, N.; Fornino, G.; Santanelli di Pompeo, F.; Accarino, G. C.

    2016-01-01

    Abstract The exposure of prosthetic vascular graft is a dangerous complication in revascularization procedures. In this case report, we describe a successful coverage of an exposed prosthetic femorofemoral vascular graft in the suprapubic area, with a vertical rectus abdominis myocutaneous (VRAM) island flap. PMID:27583274

  17. Reconstruction of concomitant total loss of the upper and lower lips with a free vertical rectus abdominis flap.

    PubMed

    Jallali, Navid; Malata, Charles M

    2005-01-01

    Total loss of both lips is fortunately rare as reconstruction of such defects poses an enormous challenge. We present a case of concomitant loss of both lips as a result of fulminant pneumococcal septicemia, which was reconstructed with a free vertical rectus abdominis myocutaneous flap due to lack of traditional donor sites. PMID:15696515

  18. Evolution of a "falx lunatica" in demarcation of critically ischemic myocutaneous tissue.

    PubMed

    Harder, Yves; Amon, Michaela; Georgi, Mirko; Banic, Andrej; Erni, Dominique; Menger, Michael D

    2005-03-01

    Using intravital microscopy in a chronic in vivo mouse model, we studied the demarcation of myocutaneous flaps and evaluated microvascular determinants for tissue survival and necrosis. Chronic ischemia resulted in a transition zone, characterized by a red fringe and a distally adjacent white falx, which defined the demarcation by dividing the proximally normal from the distally necrotic tissue. Tissue survival in the red zone was determined by hyperemia, as indicated by recovery of the transiently reduced functional capillary density, and capillary remodeling, including dilation, hyperperfusion, and increased tortuosity. Angiogenesis and neovascularization were not observed over the 10-day observation period. The white rim distal to the red zone, appearing as "falx lunatica," showed a progressive decrease of functional capillary density similar to that of the necrotic distal area but without desiccation, and thus transparency, of the tissue. Development of the distinct zones of the critically ischemic tissue could be predicted by partial tissue oxygen tension (Pt(O(2))) analysis by the time of flap elevation. The falx lunatica evolved at a Pt(O(2)) between 6.2 +/- 1.3 and 3.8 +/- 0.7 mmHg, whereas tissue necrosis developed at <3.8 +/- 0.7 mmHg. Histological analysis within the falx lunatica revealed interstitial edema formation and muscle fiber nuclear rarefaction but an absence of necrosis. We have thus demonstrated that ischemia-induced necrosis does not demarcate sharply from normal tissue but develops beside a fringe of tissue with capillary remodeling an adjacent falx lunatica that survives despite nutritive capillary perfusion failure, probably by direct oxygen diffusion.

  19. The use of free flaps in skull base reconstruction.

    PubMed

    Macía, G; Picón, M; Nuñez, J; Almeida, F; Alvarez, I; Acero, J

    2016-02-01

    Skull base tumours are rare, comprising less than 1% of all tumours of the head and neck. Surgical treatment of these tumours involves the approach, the resection, and the reconstruction of the defect, which present a challenge due to the technical difficulty and anatomical complexity. A retrospective study of 17 patients with tumours involving the skull base, treated by resection and immediate reconstruction using microsurgical free flaps, is presented; 11 were men and six were women. The following types of flap were used: osteocutaneous fibula flaps, fasciocutaneous anterolateral thigh flaps, and myocutaneous latissimus dorsi flaps. The most common histology of the tumours was squamous cell carcinoma. The most frequent point of origin was the paranasal sinuses (58.8%). All of the free flaps used for reconstruction were viable. A cerebrospinal fluid fistula occurred in two patients, and in one of these cases, meningoencephalitis led to death. In conclusion, the reconstruction of large defects of the skull base after ablation requires a viable tissue that in many cases can be obtained only through the use of microvascular free flaps. The type of flap to be selected depends on the anatomical structures and size of the defect to be restored.

  20. Intercostal artery perforator propeller flap for reconstruction of trunk defects following sarcoma resection.

    PubMed

    Zang, Mengqing; Yu, Shengji; Xu, Libin; Zhao, Zhenguo; Zhu, Shan; Ding, Qiang; Liu, Yuanbo

    2015-06-01

    Trunk defects following soft tissue sarcoma resection are usually managed by myocutaneous flaps or free flaps. However, harvesting muscle will cause functional morbidities and some trunk regions lack reliable recipient vessels. The intercostal arteries give off multiple perforators, which distribute widely over the trunk and can supply various pedicle flaps. Our purpose is to use various intercostal artery perforator propeller flaps for trunk oncologic reconstruction. Between November 2013 and July 2014, nine intercostal artery perforator propeller flaps were performed in seven patients to reconstruct the defects following sarcoma resection in different regions of the trunk, including the back, lumbar, chest, and abdomen. Two perforators from intercostal arteries were identified for each flap using Doppler ultrasound probe adjacent to the defect. The perforator with visible pulsation was chosen as the pedicle vessel. An elliptical flap was raised and rotated in a propeller fashion to repair the defects. There were one dorsal intercostal artery perforator flap, four dorsolateral intercostal artery perforator flaps, three lateral intercostal artery perforator flaps, and one anterior intercostal artery perforator flap. The mean skin paddle dimension was 9.38 cm in width (range 6-14 cm) and 21.22 cm in length (range 13-28 cm). All intercostal artery perforator flaps survived completely, except for marginal necrosis in one flap harvested close to the previous flap donor site. The intercostal artery perforator propeller flap provides various and valuable options in our reconstructive armamentarium for trunk oncologic reconstruction. To our knowledge, this is the first case series of using intercostal artery perforator propeller flaps for trunk oncologic reconstruction and clinical application of dorsolateral intercostal artery perforator flaps.

  1. [Cover flaps for loss of substance on the heel. Apropos of 8 cases].

    PubMed

    Mulfinger, C; Bardot, J; Legre, R; Aubert, J P; Magalon, G; Bureau, H

    1993-10-01

    The anatomical and function characteristics of the heel region explain the large number of methods used and the differences of opinion particularly in relation to the repair of weightbearing zones. Our study is based on 28 patients in whom we performed: ten regional flaps, six cross-leg flaps, sixteen microsurgical flaps. The temporal fascia free flap provides good results on the posterior surface with minimal sequelae at the donor site. The medial plantar flap appears to be the most suitable flap for weight-bearing zones. Cross-lep flaps allow satisfactory repair of the weightbearing zone, but the scarred appearance of the donor site is inaesthetic and immobilisation is uncomfortable. The problem of large defects is still not resolved and no really satisfactory method is available among the various distant, skin, myocutaneous, pure muscle or cross-leg flaps. The solution may reside in a combination of two flaps allowing better adaptation to the morphology of the heel. The importance of heel sensation, particularly in the weight-bearing zone, led to the concept of the use of sensitive or resensitised flaps. After a review of the literature and our results, we did not find any correlation between the sensitivity obtained and the success of the reconstruction. It therefore seems useless to perform microscopic nerve sutures in order to resensitise distant heel flaps. The patient's cooperation is essential in every case to compensate for the decreased sensitivity by means of increased visual surveillance and the wearing of suitable shoes.

  2. [Perforator flaps--the evolution of a reconstructive surgical technique].

    PubMed

    Klein, S; Hage, J J; de Weerd, L

    2005-10-22

    Trauma, oncological resections and pressure sores can cause major soft tissue defects. The evolution of cutaneous, myocutaneous, and fasciocutaneous flaps currently makes possible the restoration of contour and, in many cases, function. This evolution was closely related to the increased understanding of the vascular anatomy of the skin and subcutis and has led to the development of perforator flaps. A perforator flap is a large flap of skin that survives on a single vascular stalk that perforates the muscle, referred to in briefas a 'perforator'. This has its origin in a larger vascular stalk that runs beneath the muscle. The vascular stalk of such a perforator flap can be lengthened by dissecting the perforator from the muscle in continuity with the vessels running beneath the muscle. Moreover, the larger diameter of these vessels facilitates the creation of a vascular anastomosis in the receptor area. By the use of such perforator flaps, proper innervation and a good blood supply to the flap can be combined with less morbidity at the donor site. Important possibilities include the filling of a dorsal (decubitus) defect and breast reconstruction.

  3. The Free-style Gluteal Perforator Flap in the Thinning and Delay Process for Perineal Reconstruction After Necrotizing Fasciitis.

    PubMed

    Horta, Ricardo; Nascimento, Ricardo; Silva, Alvaro; Amarante, Jose

    2016-06-01

    Perineal wounds present a special challenge for reconstructive surgeons. The vacuum-assisted closure device is useful as a temporizing measure or for wounds too large or contaminated for immediate reconstruction. Compared to traditional myocutaneous flaps, perforator flaps provide thinner fasciocutaneous flaps for perineal reconstruction with favorable results and fewer donor site morbidities. The upper and lower gluteal regions are rich in perforators, which allow for more versatile flap design according to the defect. The authors combined the principles of free-style perforator flaps, flap delay, and thinning of perforator flaps to restore perineal function and aesthetics. The procedure was undertaken in a 72-year-old female who was obese with the diagnosis of necrotizing fasciitis secondary to perineal abscess. After 3 months, the flap achieved adequate and durable reconstruction with acceptable aesthetic contour and patient satisfaction; there was no loss of function at donor sites. Clinical applications and technical refinements of freestyle pedicled perforator flaps can be extended to the perineal region. Because of its many advantages and its versatility, freestyle pedicled perforator flaps constitute a valued reconstructive option and, when indicated, an alternative to pedicled axial flaps or even free flaps, in addition to vacuum therapy, to simplify the reconstructive procedure. PMID:27434419

  4. An investigation of the application of laser-assisted indocyanine green fluorescent dye angiography in pedicle transverse rectus abdominus myocutaneous breast reconstruction

    PubMed Central

    Newman, Martin I; Samson, Michel C; Tamburrino, Joseph F; Swartz, Kimberly A; Brunworth, Louis

    2011-01-01

    BACKGROUND: Pedicle transverse rectus abdominus myocutaneous (pTRAM) flaps remain the most common method of autologous tissue breast reconstruction. Using pTRAM flaps, complications often arise postoperatively, secondary to inadequate circulation. Tissues from distant angiosomes are associated with poorer perfusion, but this differs among patients. Many modalities have been used to reduce the risk of complications, but none have achieved widespread application. The authors believe that laser-assisted indocyanine green fluorescent dye angiography (LA-ICGA) can potentially reduce the risk of complications. METHODS: In two routine, single-pedicle, ipsilateral pTRAM flaps, LA-ICGA imaging was performed following the division of the distal rectus muscle and deep inferior epigastric pedicle. The resulting images were used to guide design of the flap and debridement. RESULTS: In case 1, good perfusion was observed in zone 1 and part of zone 2. In case 2, good perfusion was observed in zone 1 and 50% of zone 3, with little perfusion in zone 2. In both cases, tissues with poor perfusion were debrided before transfer and inset. In both patients, there were no issues with wound healing, tissue necrosis or fat necrosis. CONCLUSIONS: The variability of perfusion of the pTRAM flap among individuals is well appreciated. LA-ICGA helped to determine the limits of good perfusion and, therefore, the limits of tissue to be preserved for transfer and inset. This helped to avoid harvesting poorly perfused tissue that would have almost certainly experienced necrosis and, ultimately, would have reduced the risk of postoperative complications. PMID:22379372

  5. Systematic Review and Operative Technique of Recalcitrant Pressure Ulcers Using a Fillet Flap Technique

    PubMed Central

    Rao, Venkat K.

    2016-01-01

    Background: The purpose of this article is to describe the indications, operative technique, outcomes, and systematic review of the literature on the reconstruction of patients with end-stage pressure ulcers using a fillet flap technique. In this technique, the femur, tibia, and fibula are removed from the thigh and leg, and the soft tissue is used as a pedicled, or free, myocutaneous flap for reconstruction. Long-term outcomes, salient surgical technique of flap elevation, and design are detailed for patients who had a fillet of leg flap for reconstruction of extensive pressure ulcers. Methods: The indications, surgical technique, and postoperative outcomes of 5 patients who had pedicled fillet flaps are reviewed including patient age, sex, underlying comorbidities, duration of paraplegia, operative technique, and complications. A systematic review of the literature was performed searching PubMed, Cochrane Database, and Medline with the following MeSH terms: pressure ulcer, pressure sore, decubitus ulcer, fillet flap, and fillet flap. Inclusion criteria were use of a fillet technique, article data on the number of reconstructions before fillet flap, complications, and English language. Results: Most of our patients were male 75% (n = 3) with an average age of 47.5 years, had been paralyzed for an average of 16 years, and had few medical comorbidities. Two patients (3 flaps) required hip disarticulation, 1 patient had a bilateral fillet flaps, and 3 patients had resection of tibia/fibula. After following patients for an average of 1.4 years (4 mo to 2 yr), complications were limited to 1 patient who had partial-thickness flap loss at the distal skin flap that healed by secondary intention and 1 patient who had ulcer recurrence because of noncompliance. Four articles met inclusion criteria for systematic review and 3 were excluded. Conclusions: The fillet of leg flap remains a useful and reliable method of reconstructing end-stage pressure ulcers. PMID:27622082

  6. Systematic Review and Operative Technique of Recalcitrant Pressure Ulcers Using a Fillet Flap Technique

    PubMed Central

    Rao, Venkat K.

    2016-01-01

    Background: The purpose of this article is to describe the indications, operative technique, outcomes, and systematic review of the literature on the reconstruction of patients with end-stage pressure ulcers using a fillet flap technique. In this technique, the femur, tibia, and fibula are removed from the thigh and leg, and the soft tissue is used as a pedicled, or free, myocutaneous flap for reconstruction. Long-term outcomes, salient surgical technique of flap elevation, and design are detailed for patients who had a fillet of leg flap for reconstruction of extensive pressure ulcers. Methods: The indications, surgical technique, and postoperative outcomes of 5 patients who had pedicled fillet flaps are reviewed including patient age, sex, underlying comorbidities, duration of paraplegia, operative technique, and complications. A systematic review of the literature was performed searching PubMed, Cochrane Database, and Medline with the following MeSH terms: pressure ulcer, pressure sore, decubitus ulcer, fillet flap, and fillet flap. Inclusion criteria were use of a fillet technique, article data on the number of reconstructions before fillet flap, complications, and English language. Results: Most of our patients were male 75% (n = 3) with an average age of 47.5 years, had been paralyzed for an average of 16 years, and had few medical comorbidities. Two patients (3 flaps) required hip disarticulation, 1 patient had a bilateral fillet flaps, and 3 patients had resection of tibia/fibula. After following patients for an average of 1.4 years (4 mo to 2 yr), complications were limited to 1 patient who had partial-thickness flap loss at the distal skin flap that healed by secondary intention and 1 patient who had ulcer recurrence because of noncompliance. Four articles met inclusion criteria for systematic review and 3 were excluded. Conclusions: The fillet of leg flap remains a useful and reliable method of reconstructing end-stage pressure ulcers.

  7. Comparison of Long-Term Outcomes of Postmastectomy Radiotherapy between Breast Cancer Patients with and without Immediate Flap Reconstruction

    PubMed Central

    Lee, Hsin-Hua; Hou, Ming-Feng; Wei, Shu-Yi; Lin, Sin-Daw; Luo, Kuei-Hau; Huang, Ming-Yii; Ou-Yang, Fu; Huang, Chih-Jen

    2016-01-01

    Purpose To compare the long-term clinical outcomes of postmastectomy radiotherapy (PMRT) between breast cancer patients with and without immediate transverse rectus abdominis myocutaneous (TRAM) flap reconstruction. Methods The study included 492 patients with stage II or III breast cancer who underwent modified radical mastectomy (MRM) and chemotherapy followed by PMRT between 1997 and 2011. Cox regression model and Kaplan-Meier curves were calculated, and the log-rank test was used to evaluate the differences between overall and disease-free survival rates in the 2 groups. Results Among 492 patients, 213 patients had immediate TRAM flap reconstruction. The mean follow-up was 7.2 years (range, 11–191 months). The 5-year and 10-year disease free survival rates were 81% and 76% for the TRAM flap group and 78% and 73% for the non-flap group. The 5-year and 10-year overall survival rates were 89% and 73% for the TRAM flap group and 83% and 74% for the non-flap group. Conclusions There exists no statistically significant difference in the rates of local recurrence, distant metastasis, disease-free and overall survival when comparing immediate TRAM flap reconstruction with no reconstruction. Our results suggest that immediate TRAM flap reconstruction does not compromise long term clinical outcomes in breast cancer patients requiring PMRT. PMID:26863006

  8. Preoperative TRAM free flap volume estimation for breast reconstruction in lean patients.

    PubMed

    Minn, Kyung Won; Hong, Ki Yong; Lee, Sang Woo

    2010-04-01

    To obtain pleasing symmetry in breast reconstruction with transverse rectus abdominis myocutaneous (TRAM) free flap, a large amount of abdominal flap is elevated and remnant tissue is trimmed in most cases. However, elevation of abundant abdominal flap can cause excessive tension in donor site closure and increase the possibility of hypertrophic scarring especially in lean patients. The TRAM flap was divided into 4 zones in routine manner; the depth and dimension of the 4 zones were obtained using ultrasound and AutoCAD (Autodesk Inc., San Rafael, CA), respectively. The acquired numbers were then multiplied to obtain an estimate of volume of each zone and the each zone volume was added. To confirm the relation between the estimated volume and the actual volume, authors compared intraoperative actual TRAM flap volumes with preoperative estimated volumes in 30 consecutive TRAM free flap breast reconstructions. The estimated volumes and the actual elevated volumes of flap were found to be correlated by regression analysis (r = 0.9258, P < 0.01). According to this result, we could confirm the reliability of the preoperative volume estimation using our method. Afterward, the authors applied this method to 7 lean patients by estimation and revision of the design and obtained symmetric results with minimal donor site morbidity. Preoperative estimation of TRAM flap volume with ultrasound and AutoCAD (Autodesk Inc.) allow the authors to attain the precise volume desired for elevation. This method provides advantages in terms of minimal flap trimming, easier closure of donor sites, reduced scar widening and symmetry, especially in lean patients.

  9. Breast reconstruction with single-pedicle TRAM flap in breast cancer patients with low midline abdominal scar

    PubMed Central

    Wu, Jun-Dong; Huang, Wen-He; Qiu, Si-Qi; He, Li-Fang; Guo, Cui-Ping; Zhang, Yong-Qu; Zhang, Fan; Zhang, Guo-Jun

    2016-01-01

    Breast reconstruction with transverse rectus abdominis myocutaneous (TRAM) flap is challenging in patients with low midline abdominal scar. In this study, we aimed to investigate the clinical feasibility of immediate breast reconstruction using single-pedicle TRAM (SP-TRAM) flaps in patients with low midline abdominal scar. There were 4 strict selection criteria: 1) presence at least 3 perforators on the pedicle side; 2) perforators with regional average flow velocity of >20 cm/s; 3) upper edge of the abdominal scar at least 4 cm from the umbilicus; and 4) scar age >1 year. Eight breast cancer patients with low midline abdominal scar (scar group) and 20 without (control group) underwent immediate breast reconstruction with SP-TRAM flaps consisting of zone I and III and zone II tissues. Flap complications, donor-site complications, and cosmetic results were compared between the two groups. All flaps survived and both groups presented similar flap and donor site complications, including fat necrosis, seroma, hematoma, infection, delayed wound healing, and abdominal hernia, and patients in both groups had similar aesthetic results (p > 0.05). Thus, the study demonstrated that breast reconstruction using SP-TRAM flap was a safe approach in carefully selected patients with low midline abdominal scar. PMID:27406872

  10. Continuous tissue oxygen tension measurement as a monitor of free-flap viability.

    PubMed

    Hirigoyen, M B; Blackwell, K E; Zhang, W X; Silver, L; Weinberg, H; Urken, M L

    1997-03-01

    Early recognition of vascular compromise within microvascular free-tissue transfers is essential if reexploration is to prove successful. Tissue oxygen tension is increasingly recognized to be a sensitive and reliable index of tissue perfusion, and preliminary studies suggest that it may be of value in the assessment of free-flap viability. We describe our investigation into the application of an implantable microcatheter oxygen sensor in the monitoring of free flaps used in head and neck and extremity reconstruction. In a preliminary study using the rabbit model, we sought to evaluate the response of oxygen tension as an index of tissue perfusion in myocutaneous (n = 20) and osteomyocutaneous flaps (n = 5) under conditions of arterial and venous occlusion. A clinical study was then undertaken to evaluate the role of this method in the monitoring of surface and buried free flaps. In 30 heterogeneous free-tissue transfers, sensors placed intraoperatively were used to provide continuous information about flap oxygen tension (mean monitoring period 3.2 +/- 0.8 days). The data generated were correlated with changes in clinical parameters and routine flap observations. Results for experimental and clinical data have confirmed the efficacy of continuous tissue oxygen measurements using this device as a method that provides an objective, recordable index of free-tissue transfer viability in a variety of circumstances and vascular events. Tissue oxygen tension is a suitable index by which to evaluate flap viability with the probe placed in muscle or bone but is unreliable when used for the monitoring of revascularized cutaneous flaps. PMID:9047197

  11. Technique for Minimizing Donor-site Morbidity after Pedicled TRAM-Flap Breast Reconstruction: Outcomes by a Single Surgeon’s Experience

    PubMed Central

    Rietjens, Mario; De Lorenzi, Francesca; Andrea, Manconi; Petit, Jean-Yves; Hamza, Alaa; Martella, Stefano; Barbieri, Benedetta; Gottardi, Alessandra; Giuseppe, Lomeo

    2015-01-01

    Background: Breast reconstruction with pedicled transverse rectus abdominis myocutaneous (TRAM) flap can result in significant abdominal wall donor-site morbidity. We present our technique of transversely dividing the anterior fascia and rectus abdominis combined with reinforcement above the arcuate line for closure of the anterior abdominal wall defect to prevent contour deformities performed by a single senior surgeon and compare these results with those of our prior series. Methods: We described our new technique of closure of the abdominal wall defect and retrospectively performed the comparison between the results of pedicled TRAM flaps using the new closure technique and those of 420 pedicled TRAM flaps from our 2003 publication in terms of abdominal bulging and hernia. Results: Sixty-seven pedicled TRAM flaps in 65 patients were compared with 420 pedicled TRAM flaps of the 2003 series. The new technique was associated with 5 partial TRAM flap necroses (8%). There was no total flap loss with the new technique. The median follow-up period was 13 months (range, 4–36 months). There were no instances of abdominal hernia and bulge during follow-up in the new series. Compared with the previous 2003 series, the new technique was superior in terms of occurrence of abdominal wall hernia or bulging. Conclusions: We are still performing pedicled TRAM flap for autologous breast reconstruction. Using the technique of transversely dividing the anterior fascia and rectus abdominis combined with reinforcement above the arcuate line can reduce the occurrence of abdominal bulging and hernia. PMID:26495189

  12. The racquet conjunctival flap.

    PubMed

    Cies, W A; Odeh-Nasrala, N

    1976-01-01

    In situations requiring a conjunctival flap to cover a corneal defect, the racquet flap technique is a simple relatively noninvasive method. Less conjunctiva is sacrificed and yet the flap is fully maintained by the one pedicle. The bulbar conjunctiva is maintained in an essentially normal state.

  13. The Use of Composite Flaps in the Management of Large Full-Thickness Defects of the Lower Eyelid

    PubMed Central

    Fang, Shuo; Yang, Chao; Zhang, Yuntong; Xue, Chunyu; Bi, Hongda; Dai, Haiying; Xing, Xin

    2016-01-01

    Abstract To describe a modified surgical procedure that uses a combination of the tarsoconjunctival flap, orbicularis myocutaneous advancement flap, and paranasal-island flap to correct extensive full-thickness lower eyelid defects in functioning eyes. From May 2010 to December 2013, a total of 15 patients had reconstructive surgeries of large to giant lower eyelid defect, with an average 19-month follow-up. The musculocutaneous flaps were harvested from both orbicularis and paranasal regions and clinical outcomes were recorded and analyzed. No major complications were observed in any of the patients. All the patients showed aesthetic eyelid contour, good color, and texture match as well as no obvious scar formation. The mean Marginal Reflex Distance-2 measured 4 months after surgery was 4.9 ± 0.4 mm. Reconstruction of a large defect in the lower eyelid with a tarsoconjunctival flap and the composite neighboring musculocutaneous flaps is a reliable and reproducible method. With proper design and well-executed precision, excellent functional and aesthetic results can be achieved by this elegant procedure without any major complications. PMID:26765467

  14. Three-step orbitofacial reconstruction after extended total maxillectomy using free RAM flap and expanded cervicofacial flap with cartilage grafts.

    PubMed

    Kajikawa, Akiyoshi; Ueda, Kazuki; Katsuragi, Yoko; Hirose, Taro; Asai, Emiko

    2010-10-01

    Facial defect after an extended total maxillectomy is one of the most difficult deformities to reconstruct aesthetically, because the defect is not only large but also three-dimensional. Although free-flap reconstruction is useful, the patchwork-like scar, bad colour match and poor texture match are major problems. The contracture and displacement of the reconstructed eyelids and eye socket are also serious matters. To resolve these problems, we have performed a three-step reconstruction using a free rectus abdominis myocutaneous (RAM) flap and an expanded cervicofacial flap with cartilage grafts. In the first step, a free RAM flap was transplanted to the defect after extended total maxillectomy. In the second step, tissue expanders were placed under the skin of the cheek and neck a year after the RAM flap transplantation. After expansion of the cheek and neck skin, the third step was performed. The inferior part of the external skin island of the RAM flap was raised and sutured to the superior margin of the skin island to create a pouch for the eye socket. Costal cartilage was grafted to reconstruct the orbital floor and malar prominence, and auricular cartilage was grafted to reconstruct the tarsal plates. Finally, the expanded cervicofacial flap was rotated to cover this construct. Two weeks after reconstruction, the neo-eyelids were divided to form the lid fissure. We performed the three-step reconstruction on six cases after extended total maxillectomy. In all cases, a deep and stable eye socket was reconstructed. The reconstructed eyelids and cheek were natural in appearance with good colour and texture match without conspicuous scars. To obtain symmetry and natural appearance in the orbitomaxillary reconstruction, there are five points that should be formed; the eye socket, the groundwork of the eye socket, the orbital floor and malar prominence, the tarsal plates and the surface of the eyelids and cheek. We do not reconstruct the palate to set prosthetic

  15. Local flap therapy for the treatment of pressure sore wounds.

    PubMed

    Wettstein, Reto; Tremp, Mathias; Baumberger, Michael; Schaefer, Dirk J; Kalbermatten, Daniel F

    2015-10-01

    The aim of this study was to analyse the effectiveness of an interdisciplinary cooperation between conservative and surgical disciplines for the treatment of pressure sores (PS). From January 2004 to December 2005, a single-centre study was performed with paraplegic and tetraplegic patients presenting with PS grades III-V. Outcome measures were defect size, grade, method of reconstruction, complication and recurrence rate as well as average length of hospitalisation. A total of 119 patients aged 22-84 years with totally 170 PS were included. The most common PS were located in the ischial region (47%), followed by the sacral (18%), trochanteric (11%), foot (9%) and the malleolar (8%) regions. Defect sizes ranged between 4 and 255 cm(2) . Grade IV was the most common PS (68%), followed by grade III (30%) and grade V (2%) PS. For wound closure, fasciocutaneous flaps were used most frequently (71%), followed by skin grafts (10%) and myocutaneous flaps (7%). Postoperative follow-up ranged between 6 and 38 months. The overall complication and recurrence rate was 26% and 11%, respectively. If no complication occurred, the average duration of hospitalisation stay after the first debridement was 98 ± 62 days. In conclusion, our treatment concept is reliable, effective and results in a low recurrence rate. The complication rate, even though favourable when compared with the literature, still needs to be improved.

  16. A comparison of the effects of epidural and spinal anesthesia with ischemia-reperfusion injury on the rat transverse rectus abdominis musculocutaneous flap.

    PubMed

    Acar, Yusuf; Bozkurt, Mehmet; Firat, Ugur; Selcuk, Caferi Tayyar; Kapi, Emin; Isik, Fatma Birgul; Kuvat, Samet Vasfi; Celik, Feyzi; Bozarslan, Beri Hocaoglu

    2013-11-01

    The purpose of this study is to compare the effects of spinal and epidural anesthesia on a rat transverse rectus abdominus myocutaneous flap ischemia-reperfusion injury model.Forty Sprague-Dawley rats were divided into 4 experimental groups: group I (n = 10), sham group; group II (n = 10), control group; group III (n = 10), epidural group; and group IV (n = 10), spinal group. After the elevation of the transverse rectus abdominus myocutaneous flaps, all groups except for the sham group were subjected to normothermic no-flow ischemia for 4 hours, followed by a reperfusion period of 2 hours. At the end of the reperfusion period, biochemical and histopathological evaluations were performed on tissue samples.Although there was no significant difference concerning the malonyldialdehyde, nitric oxide, and paraoxonase levels in the spinal and epidural groups, the total antioxidant state levels were significantly increased, and the total oxidative stress levels were significantly decreased in the epidural group in comparison to the spinal group. The pathological evaluation showed that findings related to inflammation, nuclear change rates and hyalinization were significantly higher in the spinal group compared with the epidural group.Epidural anesthesia can be considered as a more suitable method that enables a decrease in ischemia-reperfusion injuries in the muscle flaps.

  17. Flow Over Swept Flaps and Flap Tips

    NASA Technical Reports Server (NTRS)

    Bradshaw, Peter; Buice, Carl U.

    1995-01-01

    Preliminary measurements have been made of the flow over the tip of an unswept wing flap. To achieve an acceptable Reynolds number based on flap chord, the flap chord was chosen equal to the chord of the main airfoil (c = 19 in. approx. 0.48 m). The model was mounted in a 30 in. x 30 in. wind tunnel running at up to 100 ft/sec. (30 m/s): severe wind-tunnel interference was accepted, and any computations would be done using the tunnel walls as the boundaries of the computational domain. Maximum Reynolds number based on flap chord and tunnel speed was about 1.O x lO(exp 6). The grant ended before a full set of measurements could be made, but the work done so far yields a useful picture of the flow. The vortex originates at about mid-chord on the flap and rises rapidly above the chord line. It has a concentrated core, with total pressure lower than the ambient static pressure, and there is no evidence of large-scale wandering. A simple method of model construction, giving light weight and excellent surface finish, was developed.

  18. Facial flap complications.

    PubMed

    Zoumalan, Richard A; Murakami, Craig S

    2012-06-01

    Knowledge of fundamental concepts can help decrease the chance of complications in plastic surgery. Local flap reconstruction for facial defects has many pitfalls. This article describes common complications in local flap reconstruction of the face and describes strategies that prevent problems.

  19. [The abdominal drop flap].

    PubMed

    Bodin, F; Liverneaux, P; Seigle-Murandi, F; Facca, S; Bruant-Rodier, C; Dissaux, C; Chaput, B

    2015-08-01

    The skin between the mastectomy scar and the future infra-mammary fold may be managed in different ways in delayed breast reconstruction using a DIEP (deep inferior epigastric perforator). Conserving this skin and positioning the flap skin paddle in the middle of the breast usually highlights skin color disparity because of two visible transition zones. Resection of the entire skin under the scar may be more aesthetic but limits direct closure possibility in case of flap failure. In order to benefit from both aesthetic result and safe surgical method, we propose the abdominal drop flap. The inferior thoracic skin flap is detached from the thoracic wall beyond the future infra-mammary fold, preserved and pushed under the breast.

  20. Total arm flap.

    PubMed

    Becker, D W

    1987-11-01

    The development of an unusual and rarely indicated total arm flap is described in the context of widely indicated and automatically used principles passed down by the recognized father of plastic surgery, Sir Harold G. Gillies.

  1. Flapping of Insectile Wings

    NASA Astrophysics Data System (ADS)

    Huang, Yangyang; Kanso, Eva

    2015-11-01

    Insects use flight muscles attached at the base of the wings to produce impressive wing flapping frequencies. Yet the effects of muscle stiffness on the performance of insect wings remain unclear. Here, we construct an insectile wing model, consisting of two rigid wings connected at their base by an elastic torsional spring and submerged in an oscillatory flow. The wing system is free to rotate and flap. We first explore the extent to which the flyer can withstand roll perturbations, then study its flapping behavior and performance as a function of spring stiffness. We find an optimal range of spring stiffness that results in large flapping amplitudes, high force generation and good storage of elastic energy. We conclude by conjecturing that insects may select and adjust the muscle spring stiffness to achieve desired movement. These findings may have significant implications on the design principles of wings in micro air-vehicles.

  2. Control of Flap Vortices

    NASA Technical Reports Server (NTRS)

    Greenblatt, David

    2005-01-01

    A wind tunnel investigation was carried out on a semi-span wing model to assess the feasibility of controlling vortices emanating from outboard flaps and tip-flaps by actively varying the degree of boundary layer separation. Separation was varied by means of perturbations produced from segmented zero-efflux oscillatory blowing slots, while estimates of span loadings and vortex sheet strengths were obtained by integrating wing surface pressures. These estimates were used as input to inviscid rollup relations as a means of predicting changes to the vortex characteristics resulting from the perturbations. Surveys of flow in the wake of the outboard and tip-flaps were made using a seven-hole probe, from which the vortex characteristics were directly deduced. Varying the degree of separation had a marked effect on vortex location, strength, tangential velocity, axial velocity and size for both outboard and tip-flaps. Qualitative changes in vortex characteristics were well predicted by the inviscid rollup relations, while the failure to account for viscosity was presumed to be the main reason for observed discrepancies. Introducing perturbations near the outboard flap-edges or on the tip-flap exerted significant control over vortices while producing negligible lift excursions.

  3. Blowing Flap Experiment: PIV Measurements

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Stead, Daniel J.; Bremmer, David M.

    2004-01-01

    PIV measurements of the flow in the region of a flap side edge are presented for several flap configurations. The test model is a NACA 63(sub 2)-215 Hicks Mod-B main element airfoil with a half-span Fowler flap. Air is blown from small slots located along the flap side edge on either the top, bottom or side surfaces. The test set up is described and flow measurements for a baseline and three blowing flap configurations are presented. The effects that the flap tip jets have on the structure of the flap side edge flow are discussed for each of the flap configurations tested. The results indicate that blowing air from a slot located along the top surface of the flap greatly weakened the top vortex system and pushed it further off the top surface. Blowing from the bottom flap surface kept the strong side vortex further outboard while blowing from the side surface only strengthened the flap vortex system. It is concluded that blowing from the top or bottom surfaces of the flap may lead to a reduction of flap side edge noise.

  4. Flap Endonuclease 1

    PubMed Central

    Balakrishnan, Lata; Bambara, Robert A.

    2013-01-01

    First discovered as a structure-specific endonuclease that evolved to cut at the base of single-stranded flaps, flap endonuclease (FEN1) is now recognized as a central component of cellular DNA metabolism. Substrate specificity allows FEN1 to process intermediates of Okazaki fragment maturation, long-patch base excision repair, telomere maintenance, and stalled replication fork rescue. For Okazaki fragments, the RNA primer is displaced into a 5′ flap and then cleaved off. FEN1 binds to the flap base and then threads the 5′ end of the flap through its helical arch and active site to create a configuration for cleavage. The threading requirement prevents this active nuclease from cutting the single-stranded template between Okazaki fragments. FEN1 efficiency and specificity are critical to the maintenance of genome fidelity. Overall, recent advances in our knowledge of FEN1 suggest that it was an ancient protein that has been fine-tuned over eons to coordinate many essential DNA transactions. PMID:23451868

  5. Bilobed flap in sole surgery

    SciTech Connect

    Sanchez-Conejo-Mir, J.; Bueno Montes, J.; Moreno Gimenez, J.C.; Camacho-Martinez, F.

    1985-09-01

    The bilobed flap is a simple reconstructive technique principally used to correct substantial defects in the facial region. The authors present their experience with this local flap in the difficult plantar area, with excellent short-term functional results. They describe the special characteristics of the bilobed flap in this zone, and comment on its indications and possible complications.

  6. Local Flaps of The Hand

    PubMed Central

    Rehim, Shady A.; Chung, Kevin C.

    2014-01-01

    Synopsis A local flap consists of skin and subcutaneous tissue that is harvested from a site nearby a given defect while maintaining its intrinsic blood supply. When a soft tissue defect of the hand is not amenable to primary closure or skin grafting, local skin flaps can be a used as a reliable source of soft tissue replacement that replaces like with like. Flaps are categorized based on their composition, method of transfer, flap design and blood supply, yet flap circulation is considered the most critical factor for the flap survival. This article reviews the classification of local skin flaps of the hand and offers a practical reconstructive approach for several soft tissue defects of the hand and digits. PMID:24731606

  7. Noise Reduction of Aircraft Flap

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V. (Inventor); Brooks, Thomas F. (Inventor)

    2009-01-01

    A reduction in noise radiating from a side of a deployed aircraft flap is achieved by locating a slot adjacent the side of the flap, and then forcing air out through the slot with a suitable mechanism. One, two or even three or more slots are possible, where the slot is located at one;or more locations selected from a group of locations comprising a top surface of the flap, a bottom surface of the flap, an intersection of the top and side surface of the flap, an intersection of the bottom and side surfaces of the flap, and a side surface of the flap. In at least one embodiment the slot is substantially rectangular. A device for adjusting a rate of the air forced out through the slot can also be provided.

  8. The Deltopectoral Flap Revisited: The Internal Mammary Artery Perforator Flap.

    PubMed

    Ibrahim, Amir; Atiyeh, Bishara; Karami, Reem; Adelman, David M; Papazian, Nazareth J

    2016-03-01

    Pharyngo-esophageal and tracheostomal defects pose a challenge in head and neck reconstruction whenever microanastomosis is extremely difficult in hostile neck that is previously dissected and irradiated. The deltopectoral (DP) flap was initially described as a pedicled flap for such reconstruction with acceptable postoperative results. A major drawback is still that the DP flap is based on 3 perforator vessels leading to a decreased arc of rotation. The DP flap also left contour deformities in the donor site. The internal mammary artery perforator flap was described as a refinement of the deltopectoral flap. It is a pedicled fasciocutaneous flap based on a single perforator, with comparable and reliable blood supply compared with the DP flap, giving it the benefit of having a wide arc of rotation. It is both thin and pliable, with good skin color match and texture. The donor site can be closed primarily with no esthetic deformity and minimal morbidity. The procedure is relatively simple and does not require microvascular expertise. In this report, the authors describe a patient in whom bilateral internal mammary artery perforator flaps were used for subtotal pharyngo-esophageal reconstruction and neck resurfacing. The flaps healed uneventfully bilaterally with no postoperative complications. PMID:26854779

  9. Skin flaps and grafts - self-care

    MedlinePlus

    ... Free flap - self-care; Skin autografting - self-care; Pressure ulcer skin flap self-care; Burns skin flap self- ... skin infection Surgery for skin cancer Venous ulcers , pressure ulcers , or diabetic ulcers that DO NOT heal After ...

  10. Flexible Flapping Foils

    NASA Astrophysics Data System (ADS)

    Marais, Catherine; Godoy-Diana, Ramiro; Wesfreid, José. Eduardo

    2010-11-01

    Hydrodynamic tunnel experiments with flexible flapping foils of 4:1 span-to-chord aspect ratio are used in the present work to study the effect of foil compliance in the dynamical features of a propulsive wake. The average thrust force produced by the foil is estimated from 2D PIV measurements and the regime transitions in the wake are characterized according to a flapping frequency-amplitude phase diagram as in Godoy-Diana et al. (Phys. Rev. E 77, 016308, 2008). We show that the thrust production regime occurs on a broader region of the parameter space for flexible foils, with propulsive forces up to 3 times greater than for the rigid case. We examine in detail the vortex generation at the trailing edge of the foils, and propose a mechanism to explain how foil deformation leads to an optimization of propulsion.

  11. Engineered Vascularized Muscle Flap.

    PubMed

    Egozi, Dana; Shandalov, Yulia; Freiman, Alina; Rosenfeld, Dekel; Ben-Shimol, David; Levenberg, Shulamit

    2016-01-01

    One of the main factors limiting the thickness of a tissue construct and its consequential viability and applicability in vivo, is the control of oxygen supply to the cell microenvironment, as passive diffusion is limited to a very thin layer. Although various materials have been described to restore the integrity of full-thickness defects of the abdominal wall, no material has yet proved to be optimal, due to low graft vascularization, tissue rejection, infection, or inadequate mechanical properties. This protocol describes a means of engineering a fully vascularized flap, with a thickness relevant for muscle tissue reconstruction. Cell-embedded poly L-lactic acid/poly lactic-co-glycolic acid constructs are implanted around the mouse femoral artery and vein and maintained in vivo for a period of one or two weeks. The vascularized graft is then transferred as a flap towards a full thickness defect made in the abdomen. This technique replaces the need for autologous tissue sacrifications and may enable the use of in vitro engineered vascularized flaps in many surgical applications. PMID:26779840

  12. The Versatile Modiolus Perforator Flap

    PubMed Central

    Gunnarsson, Gudjon Leifur; Thomsen, Jorn Bo

    2016-01-01

    Background: Perforator flaps are well established, and their usefulness as freestyle island flaps is recognized. The whereabouts of vascular perforators and classification of perforator flaps in the face are a debated subject, despite several anatomical studies showing similar consistency. In our experience using freestyle facial perforator flaps, we have located areas where perforators are consistently found. This study is focused on a particular perforator lateral to the angle of the mouth; the modiolus and the versatile modiolus perforator flap. Methods: A cohort case series of 14 modiolus perforator flap reconstructions in 14 patients and a color Doppler ultrasonography localization of the modiolus perforator in 10 volunteers. Results: All 14 flaps were successfully used to reconstruct the defects involved, and the location of the perforator was at the level of the modiolus as predicted. The color Doppler ultrasonography study detected a sizeable perforator at the level of the modiolus lateral to the angle of the mouth within a radius of 1 cm. This confirms the anatomical findings of previous authors and indicates that the modiolus perforator is a consistent anatomical finding, and flaps based on it can be recommended for several indications from the reconstruction of defects in the perioral area, cheek and nose. Conclusions: The modiolus is a well-described anatomical area containing a sizeable perforator that is consistently present and readily visualized using color Doppler ultrasonography. We have used the modiolus perforator flap successfully for several indications, and it is our first choice for perioral reconstruction. PMID:27257591

  13. Flag flapping in a channel

    NASA Astrophysics Data System (ADS)

    Alben, Silas; Shoele, Kourosh; Mittal, Rajat; Jha, Sourabh; Glezer, Ari

    2015-11-01

    We study the flapping of a flag in an inviscid channel flow. We focus especially on how quantities vary with channel spacing. As the channel walls move inwards towards the flag, heavier flags become more unstable, while light flags' stability is less affected. We use a vortex sheet model to compute large-amplitude flapping, and find that the flag undergoes a series of jumps to higher flapping modes as the channel walls are moved towards the flag. Meanwhile, the drag on the flag and the energy lost to the wake first rise as the walls become closer, then drop sharply as the flag moves to a higher flapping mode.

  14. Reduction of Flap Side Edge Noise - the Blowing Flap

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Brooks, THomas F.

    2005-01-01

    A technique to reduce the noise radiating from a wing-flap side edge is being developed. As an airplane wing with an extended flap is exposed to a subsonic airflow, air is blown outward through thin rectangular chord-wise slots at various locations along the side edges and side surface of the flap to weaken and push away the vortices that originate in that region of the flap and are responsible for important noise emissions. Air is blown through the slots at up to twice the local flow velocity. The blowing is done using one or multiple slots, where a slot is located along the top, bottom or side surface of the flap along the side edge, or also along the intersection of the bottom (or top) and side surfaces.

  15. Flap-Edge Blowing Experiments

    NASA Technical Reports Server (NTRS)

    Gaeta, R. J.; Englar, R. J.; Ahuja, K. K.

    2003-01-01

    This Appendix documents the salient results from an effort to mitigate the so-called flap-edge noise generated at the split between a flap edge that is deployed and the undeployed flap. Utilizing a Coanda surface installed at the flap edge, steady blowing was used in an attempt to diminish the vortex strength resulting from the uneven lift distribution. The strength of this lifting vortex was augmented by steady blowing over the deployed flap. The test article for this study was the same 2D airfoil used in the steady blowing program reported earlier (also used in pulsed blowing tests, see Appendix G), however its trailing edge geometry was modified. An exact duplicate of the airfoil shape was made out of fiberglass with no flap, and in the clean configuration. It was attached to the existing airfoil to make an airfoil that has half of its flap deployed and half un-deployed. Figure 1 shows a schematic of the planform showing the two areas where steady blowing was introduced. The flap-edge blowing or the auxiliary blowing was in the direction normal to the freestream velocity vector. Slot heights for the blowing chambers were on the order of 0.0 14 inches.

  16. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flap interconnection. 23.701 Section 23.701... Systems § 23.701 Flap interconnection. (a) The main wing flaps and related movable surfaces as a system must— (1) Be synchronized by a mechanical interconnection between the movable flap surfaces that...

  17. Musculocutaneous flaps in head and neck reconstruction.

    PubMed Central

    Leonard, A. G.

    1989-01-01

    The introduction of musculocutaneous flaps to head and neck reconstructive surgery is described. The flaps available are listed, and the most important ones described and illustrated. Both the latissimus dorsi and pectoralis major flaps are felt to have a role in head and neck reconstruction, though they have largely been superseded by microvascular free flaps such as the radial forearm flap. Images fig. 1 fig. 2 fig. 3 fig. 4 fig. 5 fig. 6 fig. 7 fig. 8 PMID:2686511

  18. Radiated noise from an externally blown flap

    NASA Technical Reports Server (NTRS)

    Reddy, N. N.; Yu, J. C.

    1975-01-01

    The far field noise from subsonic jet impingement on a wing-flap with a 45 deg bend was experimentally investigated. The test parameters are jet Mach number and flap length. For long flaps, the primary source mechanisms are found to be turbulent mixing and flow impingement. For short flaps, the interaction of turbulent flow with the flap trailing edge appears to strongly influence the radiated noise.

  19. Flap Edge Noise Reduction Fins

    NASA Technical Reports Server (NTRS)

    Khorrami, Mehdi R. (Inventor); Choudhan, Meelan M. (Inventor)

    2015-01-01

    A flap of the type that is movably connected to an aircraft wing to provide control of an aircraft in flight includes opposite ends, wherein at least a first opposite end includes a plurality of substantially rigid, laterally extending protrusions that are spaced apart to form a plurality of fluidly interconnected passageways. The passageways have openings adjacent to upper and lower sides of the flap, and the passageways include a plurality of bends such that high pressure fluid flows from a high pressure region to a low pressure region to provide a boundary condition that inhibits noise resulting from airflow around the end of the flap.

  20. Flap monitoring using infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Keller, Alex; Wright, Leigh P.; Elmandjra, Mohamed; Mao, Jian-min

    2006-02-01

    We report results of clinical trials on flap monitoring in 65 plastic surgeries. Hemoglobin oxygen saturation of flap tissue (StO II) was monitored non-invasively by using ODISsey TM tissue oximeter, an infrared spectroscopic device. StO II measurements were conducted both intra-operatively and post-operatively. From the intra-operative measurements, we observed that StO II values dropped when the main blood vessels supplying the flap were clamped in surgery, and that StO II jumped after anastomosis to a value close to its pre-operative value. From post-operative monitoring measurements for the 65 flap cases, each lasted two days or so, we found that the StO II values approach to a level close to the baseline if the surgery was successful, and that the StO II value dropped to a value below 30% if there is a perfusion compromise, such as vascular thrombosis.

  1. Full scale upper surface blown flap noise

    NASA Technical Reports Server (NTRS)

    Heidelberg, L. J.; Homyak, L.; Jones, W. L.

    1975-01-01

    A highly noise suppressed TF 34 engine was used to investigate the noise of several powered lift configurations involving upper surface blown (USB) flaps. The configuration variables were nozzle type (i.e. slot and circular with deflector), flap chord length, and flap angle. The results of velocity surveys at both the nozzle exit and the flap trailing edge are also presented and used for correlation of the noise data. Configurations using a long flap design were 4 db quieter than a short flap typical of current trends in USB flap design. The lower noise for the long flap is attributed primarily to the greater velocity decay of the jet at the flap trailing edge. The full-scale data revealed substantially more quadrupole noise in the region near the deflected jet than observed in previous sub-scale tests.

  2. The Role of Muscle Flaps for Salvage of Failed Perforator Free Flaps

    PubMed Central

    2015-01-01

    Background: Despite the most heroic efforts, sometimes free flaps fail. Perforator free flaps are not invincible and can suffer the same fate. The real challenge is how to decide what is the next best choice for achieving the desired outcome. Methods: Over the past decade, 298 free perforator flaps were used in our institution. Total failure occurred in 16 patients, and partial failure requiring a second free flap occurred in an additional 6 patients for a true success rate of 93%. All failures had some form of secondary vascularized tissue transfer, which included the use of muscle flaps in 9 (41%) different patients. Results: Initial flap salvage after a failed perforator free flap was attempted with 12 perforator and 5 muscle free flaps as well as 1 perforator and 2 muscle local flaps. These were not all successful, with loss of 3 muscle free flaps and 3 perforator flaps. Tertiary free flap coverage was successful in 3 cases using 2 muscle flaps and 1 perforator free flap. Local fasciocutaneous flaps or primary wound closure was used in the remaining individuals. Conclusions: Microsurgical tissue transfers can be the most rewarding and at the same time the most challenging reconstructive endeavor. Persistence in achieving the desired outcome can require multiple steps. Perforator flaps are an important asset to obtain this goal. However, muscle flaps can still be a useful alternative, and the message is that they should not be overlooked as sometimes a viable option. PMID:26893989

  3. Karydakis flap for post-proctectomy perineal sinus: A case series and review

    PubMed Central

    Au, S.; Moyes, L.H.; Telfer, J.R.C.; Anderson, J.H.

    2016-01-01

    Introduction Persistent perineal sinus (PPS) may occur in up to 38% of patients undergoing proctectomy. The available therapeutic options range from simple but ineffective to relatively successful but complex. The Karydakis procedure is a straightforward day-case operation, commonly performed by general surgeons in the treatment of pilonidal disease, a not dissimilar pathology to PPS. This report is the first in the literature describing the use of Karydakis procedure in patients who developed PPS after proctectomy for Crohn’s disease. Presentation of case Two patients, both of whom suffered from Crohn’s disease and a PPS, underwent a Karydakis procedure as first-line treatment for PPS. Case 1 had a relatively superficial PPS while Case 2 had a deeper, more complex and longstanding PPS. Both patients had no post-operative complications and were discharged on the same day. They achieved complete healing in eight weeks and eight months respectively. The follow up range was 8–16 months. Discussion Various techniques, including complex myocutaneous flap reconstruction, have been described in the literature to treat PPS. In contrast to these complex techniques, Karydakis operation is a simple day case procedure that was successful in treating PPS in our patients. While there is robust data regarding low recurrence rates following a Karydakis flap for pilonidal disease, there is no existing data for the indication outlined in this report. Conclusion While it requires further assessment, the Karydakis operation has potential as a simple, safe and effective first-line treatment in selected patients with PPS while not precluding more complex operative options in the future. PMID:27138449

  4. PIV Measurements on a Blowing Flap

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Stead, Daniel J.

    2004-01-01

    PIV measurements of the flow in the region of a flap side edge are presented for several blowing flap configurations. The test model is a NACA 63(sub 2)-215 Hicks Mod-B main-element airfoil with a half-span Fowler flap. Air is blown from small slots located along the flap side edge on either the top, bottom or side surfaces. The test set up is described and flow measurements for a baseline and three blowing flap configurations are presented. The effects that the flap tip jets have on the structure of the flap side edge flow are discussed for each of the flap configurations tested. The results indicate that blowing air from a slot located along the top surface of the flap greatly weakened the top vortex system and pushed it further off the top surface. Blowing from the bottom flap surface kept the strong side vortex further outboard while blowing from the side surface only strengthened the vortex system or accelerated the merging of the side vortex to the flap top surface. It is concluded that blowing from the top or bottom surfaces of the flap may lead to a reduction of flap side edge noise.

  5. Experimental Study of Wake / Flap Interaction Noise and the Reduction of Flap Side Edge Noise

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Stead, Daniel J.; Plassman, Gerald E.

    2016-01-01

    The effects of the interaction of a wake with a half-span flap on radiated noise are examined. The incident wake is generated by bars of various widths and lengths or by a simplified landing gear model. Single microphone and phased array measurements are used to isolate the effects of the wake interaction on the noise radiating from the flap side edge and flap cove regions. The effects on noise of the wake generator's geometry and relative placement with respect to the flap are assessed. Placement of the wake generators upstream of the flap side edge is shown to lead to the reduction of flap side edge noise by introducing a velocity deficit and likely altering the instabilities in the flap side edge vortex system. Significant reduction in flap side edge noise is achieved with a bar positioned directly upstream of the flap side edge. The noise reduction benefit is seen to improve with increased bar width, length and proximity to the flap edge. Positioning of the landing gear model upstream of the flap side edge also leads to decreased flap side edge noise. In addition, flap cove noise levels are significantly lower than when the landing gear is positioned upstream of the flap mid-span. The impact of the local flow velocity on the noise radiating directly from the landing gear is discussed. The effects of the landing gear side-braces on flap side edge, flap cove and landing gear noise are shown.

  6. Reconstruction of Rare Skull Metastases Using Free Latissimus Dorsi Flap and the Role of Preoperative Embolization in Hypervascular Skull Tumors.

    PubMed

    Singh, Mansher; Ricci, Joseph A; Talbot, Simon G; Chiocca, E Antonio; Dunn, Ian F; Caterson, Edward J

    2015-11-01

    Metastatic tumors are the most common cranial neoplasms in adults. Skull metastases from rare primary tumors, such as cholangiocarcinoma or pancreatic neuroendocrine tumor, are extremely uncommon and rarely reported. Given the scarcity and variation of these rare skull metastases, treatments and outcomes of such patients are of interest to treating surgeons. The authors describe the treatment algorithm, course, and outcomes of 2 patients with rare gastrointestinal skull metastases. The first patient had intrahepatic cholangiocarcinoma metastatic to the skull, while the second patient developed a solitary skull metastasis secondary to a pancreatic neuroendocrine tumor. As part of this report, the authors include a literature review of rare skull metastases as well as the treatment of these 2 patients. Both the patients ultimately underwent successful resection of the tumor for relief of their clinical symptoms. Wide resections in both patients necessitated reconstruction using a free latissimus dorsi muscle flap in both the patients. Preoperative embolization of the hypervascular cholangiocarcinoma skull metastasis was performed prior to resection in the first patient. To date, there have been only 4 such reports of skull metastases from intrahepatic cholangiocarcinoma and limited reported cases of isolated skull metastases from a pancreatic neuroendocrine tumor.In patients with large or numerous skull metastasis from rare primary tumors, surgical resection should be considered for symptomatic improvement. In cases of hypervascular lesions, preoperative embolization can be considered to decrease the intraoperative bleeding. Free tissue transfers using myocutaneous flaps such as latissimus dorsi help in obliterating dead space, and creating a healthy soft tissue envelope to withstand postoperative radiation treatment. In addition, a chimeric flap can be designed to include additional muscle or soft tissue to obliterate and exclude the sinus cavities.

  7. New model of flap-gliding flight.

    PubMed

    Sachs, Gottfried

    2015-07-21

    A new modelling approach is presented for describing flap-gliding flight in birds and the associated mechanical energy cost of travelling. The new approach is based on the difference in the drag characteristics between flapping and non-flapping due to the drag increase caused by flapping. Thus, the possibility of a gliding flight phase, as it exists in flap-gliding flight, yields a performance advantage resulting from the decrease in the drag when compared with continuous flapping flight. Introducing an appropriate non-dimensionalization for the mathematical relations describing flap-gliding flight, results and findings of generally valid nature are derived. It is shown that there is an energy saving of flap-gliding flight in the entire speed range compared to continuous flapping flight. The energy saving reaches the highest level in the lower speed region. The travelling speed of flap-gliding flight is composed of the weighted average of the differing speeds in the flapping and gliding phases. Furthermore, the maximum range performance achievable with flap-gliding flight and the associated optimal travelling speed are determined.

  8. Efficient flapping flight of pterosaurs

    NASA Astrophysics Data System (ADS)

    Strang, Karl Axel

    In the late eighteenth century, humans discovered the first pterosaur fossil remains and have been fascinated by their existence ever since. Pterosaurs exploited their membrane wings in a sophisticated manner for flight control and propulsion, and were likely the most efficient and effective flyers ever to inhabit our planet. The flapping gait is a complex combination of motions that sustains and propels an animal in the air. Because pterosaurs were so large with wingspans up to eleven meters, if they could have sustained flapping flight, they would have had to achieve high propulsive efficiencies. Identifying the wing motions that contribute the most to propulsive efficiency is key to understanding pterosaur flight, and therefore to shedding light on flapping flight in general and the design of efficient ornithopters. This study is based on published results for a very well-preserved specimen of Coloborhynchus robustus, for which the joints are well-known and thoroughly described in the literature. Simplifying assumptions are made to estimate the characteristics that can not be inferred directly from the fossil remains. For a given animal, maximizing efficiency is equivalent to minimizing power at a given thrust and speed. We therefore aim at finding the flapping gait, that is the joint motions, that minimize the required flapping power. The power is computed from the aerodynamic forces created during a given wing motion. We develop an unsteady three-dimensional code based on the vortex-lattice method, which correlates well with published results for unsteady motions of rectangular wings. In the aerodynamic model, the rigid pterosaur wing is defined by the position of the bones. In the aeroelastic model, we add the flexibility of the bones and of the wing membrane. The nonlinear structural behavior of the membrane is reduced to a linear modal decomposition, assuming small deflections about the reference wing geometry. The reference wing geometry is computed for

  9. Schooling of flapping wings: Simulations

    NASA Astrophysics Data System (ADS)

    Masoud, Hassan; Becker, Alexander; Ristroph, Leif; Shelley, Michael

    2014-11-01

    We examine the locomotion of an infinite array of wings that heave vertically with a prescribed sinusoidal motion and are free to translate in the horizontal direction. To do this, we simulate the motion of a freely translating flapping airfoil in a domain with periodic horizontal boundary conditions. These simulations indicate that the wings can ``take advantage'' of their collectively generated wake flows. In agreement with our experiments in a rotational geometry, we find ranges of flapping frequency over which there are multiple stable states of locomotion, with one of these swimming states having both higher speeds and efficiencies than an isolated flapping and locomoting wing. A simple mathematical model, which emphasizes the importance of history dependence in vortical flows, explains this multi-stability. These results may be important to understanding the role of hydrodynamic interactions in fish schooling and bird flocking.

  10. Sternocleidomastoid Muscle Flap after Parotidectomy

    PubMed Central

    Nofal, Ahmad Abdel-Fattah; Mohamed, Morsi

    2015-01-01

    Introduction Most patients after either superficial or total parotidectomy develop facial deformity and Frey syndrome, which leads to a significant degree of patient dissatisfaction. Objective Assess the functional outcome and esthetic results of the superiorly based sternocleidomastoid muscle (SCM) flap after superficial or total parotidectomy. Methods A prospective cohort study for 11 patients subjected to parotidectomy using a partial-thickness superiorly based SCM flap. The functional outcome (Frey syndrome, facial nerve involvement, and ear lobule sensation) and the esthetic results were evaluated subjectively and objectively. Results Facial nerve palsy occurred in 5 cases (45%), and all of them recovered completely within 6 months. The Minor starch iodine test was positive in 3 patients (27%), although only 1 (9%) subjectively complained of gustatory sweating. The designed visual analog score completed by the patients themselves ranged from 0 to 3 with a mean of 1.55 ± 0.93; the scores from the blinded evaluators ranged from 1 to 3 with a mean 1.64 ± 0.67. Conclusion The partial-thickness superiorly based SCM flap offers a reasonable cosmetic option for reconstruction following either superficial or total parotidectomy by improving the facial deformity. The flap also lowers the incidence of Frey syndrome objectively and subjectively with no reported hazard of the spinal accessory nerve. PMID:26491478

  11. The possibility for use of venous flaps in plastic surgery

    NASA Astrophysics Data System (ADS)

    Baytinger, V. F.; Kurochkina, O. S.; Selianinov, K. V.; Baytinger, A. V.; Dzyuman, A. N.

    2015-11-01

    The use of venous flaps is controversial. The mechanism of perfusion of venous flaps is still not fully understood. The research was conducted on 56 white rats. In our experimental work we studied two different models of venous flaps: pedicled venous flap (PVF) and pedicled arterialized venous flap (PAVF). Our results showed that postoperative congestion was present in all flaps. However 66.7% of all pedicled venous flaps and 100% of all pedicled arterialized venous flaps eventually survived. Histological examination revealed that postoperatively the blood flow in the skin of the pedicled arterialized venous flap became «re-reversed» again; there were no differences between mechanism of survival of venous flaps and other flaps. On the 7-14th day in the skin of all flaps were processes of neoangiogenesis and proliferation. Hence the best scenario for the clinical use of venous flaps unfolds when both revascularization and skin coverage are required.

  12. The possibility for use of venous flaps in plastic surgery

    SciTech Connect

    Baytinger, V. F. Kurochkina, O. S. Selianinov, K. V.; Baytinger, A. V.; Dzyuman, A. N.

    2015-11-17

    The use of venous flaps is controversial. The mechanism of perfusion of venous flaps is still not fully understood. The research was conducted on 56 white rats. In our experimental work we studied two different models of venous flaps: pedicled venous flap (PVF) and pedicled arterialized venous flap (PAVF). Our results showed that postoperative congestion was present in all flaps. However 66.7% of all pedicled venous flaps and 100% of all pedicled arterialized venous flaps eventually survived. Histological examination revealed that postoperatively the blood flow in the skin of the pedicled arterialized venous flap became «re-reversed» again; there were no differences between mechanism of survival of venous flaps and other flaps. On the 7-14th day in the skin of all flaps were processes of neoangiogenesis and proliferation. Hence the best scenario for the clinical use of venous flaps unfolds when both revascularization and skin coverage are required.

  13. Benefits of using omental pedicle flap over muscle flap for closure of open window thoracotomy

    PubMed Central

    Chikaishi, Yasuhiro; Kuwata, Taiji; Takenaka, Masaru; Oka, Soichi; Hirai, Ayako; Imanishi, Naoko; Kuroda, Koji; Tanaka, Fumihiro

    2016-01-01

    Background Open window thoracotomy (OWT) as well as its closure are challenging. Transposition of omental pedicle and muscle flaps is often performed for OWT closure; however, the better technique among the two is unknown. The purpose of this series was to evaluate the outcomes of using both omental pedicle and muscle flaps for the aforementioned closure. Methods This was an observational retrospective cohort study on 27 consecutive patients who underwent OWT closure at a single institution between January 2005 and December 2014. The operation was performed using either omental pedicle or muscle flap with thoracoplasty. We compared both techniques in terms of the patient background [sex, age, body mass index (BMI) and C-reactive protein (CRP) before OWT and serum albumin levels before OWT closure], presence of methicillin-resistant Staphylococcus aureus (MRSA) infection, rate of bronchopleural fistula (BPF), duration of OWT, recurrence of local infection, morbidity, duration of indwelling drainage after operation, success, mortality and postoperative hospital stay. Results There were 9 (33.3%) omental pedicle flap procedures and 18 (66.7%) muscle flap procedures. The rate of local recurrence after closure of OWT was significantly higher with muscle flap than with omental pedicle flap (0% vs. 50.0%, P=0.012). The median duration of postoperative hospital stay was significantly shorter with omental pedicle flap than that with muscle flap (16.0 vs. 41.5 days, P=0.037). Mortality was observed in 2 patients (11.2%) in the muscle flap group and no patient in the omental pedicle flap group. Success rate was similar between the two groups (100% for omental pedicle flap vs. 83.3% for muscle flap). Conclusions Omental pedicle flap was superior to muscle flap in terms of reducing local recurrence and shortening postoperative hospital stay. However, mortality, morbidity and success rates were not affected by the choice of flap. PMID:27499959

  14. Freestyle Local Perforator Flaps for Facial Reconstruction.

    PubMed

    Lee, Jun Yong; Kim, Ji Min; Kwon, Ho; Jung, Sung-No; Shim, Hyung Sup; Kim, Sang Wha

    2015-01-01

    For the successful reconstruction of facial defects, various perforator flaps have been used in single-stage surgery, where tissues are moved to adjacent defect sites. Our group successfully performed perforator flap surgery on 17 patients with small to moderate facial defects that affected the functional and aesthetic features of their faces. Of four complicated cases, three developed venous congestion, which resolved in the subacute postoperative period, and one patient with partial necrosis underwent minor revision. We reviewed the literature on freestyle perforator flaps for facial defect reconstruction and focused on English articles published in the last five years. With the advance of knowledge regarding the vascular anatomy of pedicled perforator flaps in the face, we found that some perforator flaps can improve functional and aesthetic reconstruction for the facial defects. We suggest that freestyle facial perforator flaps can serve as alternative, safe, and versatile treatment modalities for covering small to moderate facial defects. PMID:26236734

  15. Davis flap: the glory still present

    PubMed Central

    El-Sabbagh, Ahmed Hassan

    2016-01-01

    Background: Upper third defects of the ear are too large to be closed primarily without distorting the auricle. Full thickness defects can be reconstructed with local flaps. In this article, Davis flap was used to fill the upper third defects of the ear with some modifications. Patients and methods: Eight patients underwent reconstruction of full thickness auricular defects with Davis flaps from July 2012 to December 2014. The posterior surface of the flap and the raw area of conchal area were covered by full thickness graft taken from posterior surface of ear. Results: All flaps survived. No congestion was noted. The donor sites and skin grafts healed uneventfully. Conclusion: Davis flap is a simple and reproducible tool for reconstruction of upper third of ear. PMID:27274439

  16. Repositioning free laser in situ keratomileusis flaps.

    PubMed

    Todani, Amit; Al-Arfaj, Khalid; Melki, Samir A

    2010-02-01

    We describe a protocol for adequate repositioning of free laser in situ keratomileusis (LASIK) corneal flaps created by a Moria M2 microkeratome even in the absence of fiduciary marks. In an enucleated porcine globe, a free flap was created by initially placing a longitudinal incision at the proposed hinge site followed by activating the forward pass of the automated microkeratome. A protocol was devised based on placement of a positioning dot on the free flap before the flap is retrieved from the microkeratome head. Preplaced surgical landmarks were used as a guide to determine the correct alignment of the free flap. Adequate orientation of the free flap to the stromal bed was achieved in 9 porcine eyes using the positioning dot method. The technique is applicable to the Moria M2 microkeratome only and must be validated for other types of keratomes.

  17. Optimal propulsive flapping in Stokes flows.

    PubMed

    Was, Loïc; Lauga, Eric

    2014-03-01

    Swimming fish and flying insects use the flapping of fins and wings to generate thrust. In contrast, microscopic organisms typically deform their appendages in a wavelike fashion. Since a flapping motion with two degrees of freedom is able, in theory, to produce net forces from a time-periodic actuation at all Reynolds numbers, we compute in this paper the optimal flapping kinematics of a rigid spheroid in a Stokes flow. The hydrodynamics for the force generation and energetics of the flapping motion is solved exactly. We then compute analytically the gradient of a flapping efficiency in the space of all flapping gaits and employ it to derive numerically the optimal flapping kinematics as a function of the shape of the flapper and the amplitude of the motion. The kinematics of optimal flapping are observed to depend weakly on the flapper shape and are very similar to the figure-eight motion observed in the motion of insect wings. Our results suggest that flapping could be a exploited experimentally as a propulsion mechanism valid across the whole range of Reynolds numbers.

  18. Refining the intrinsic chimera flap: a review.

    PubMed

    Agarwal, Jayant P; Agarwal, Shailesh; Adler, Neta; Gottlieb, Lawrence J

    2009-10-01

    Reconstruction of complex tissue deficiencies in which each missing component is in a different spatial relationship to each other can be particularly challenging, especially in patients with limited recipient vessels. The chimera flap design is uniquely suited to reconstruct these deformities. Chimera flaps have been previously defined in many ways with 2 main categories: prefabricated or intrinsic. Herein we attempt to clarify the definition of a true intrinsic chimeric flap and provide examples of how these constructs provide a method for reconstruction of complex defects. The versatility of the intrinsic chimera flap and its procurement from 7 different vascular systems is described. A clarification of the definition of a true intrinsic chimera flap is described. In addition, construction of flaps from the lateral femoral circumflex, deep circumflex iliac, inferior gluteal, peroneal, subscapular, thoracodorsal, and radial arterial systems is described to showcase the versatility of these chimera flaps. A true intrinsic chimera flap must consist of more than a single tissue type. Each of the tissue components receives its blood flow from separate vascular branches or perforators that are connected to a single vascular source. These vascular branches must be of appropriate length to allow for insetting with 3-dimensional spatial freedom. There are a multitude of sites from which true intrinsic chimera flaps may be harvested.

  19. Optimal propulsive flapping in Stokes flows.

    PubMed

    Was, Loïc; Lauga, Eric

    2014-03-01

    Swimming fish and flying insects use the flapping of fins and wings to generate thrust. In contrast, microscopic organisms typically deform their appendages in a wavelike fashion. Since a flapping motion with two degrees of freedom is able, in theory, to produce net forces from a time-periodic actuation at all Reynolds numbers, we compute in this paper the optimal flapping kinematics of a rigid spheroid in a Stokes flow. The hydrodynamics for the force generation and energetics of the flapping motion is solved exactly. We then compute analytically the gradient of a flapping efficiency in the space of all flapping gaits and employ it to derive numerically the optimal flapping kinematics as a function of the shape of the flapper and the amplitude of the motion. The kinematics of optimal flapping are observed to depend weakly on the flapper shape and are very similar to the figure-eight motion observed in the motion of insect wings. Our results suggest that flapping could be a exploited experimentally as a propulsion mechanism valid across the whole range of Reynolds numbers. PMID:24343130

  20. Pressure Available for Cooling with Cowling Flaps

    NASA Technical Reports Server (NTRS)

    Stickle, George W; Naiman, Irven; Crigler, John L

    1941-01-01

    Report presents the results of a full-scale investigation conducted in the NACA 20-foot tunnel to determine the pressure difference available for cooling with cowling flaps. The flaps were applied to an exit slot of smooth contour at 0 degree flap angle. Flap angles of 0 degree, 15 degrees, and 30 degrees were tested. Two propellers were used; propeller c which has conventional round blade shanks and propeller f which has airfoil sections extending closer to the hub. The pressure available for cooling is shown to be a direct function of the thrust disk-loading coefficient of the propeller.

  1. Basic Perforator Flap Hemodynamic Mathematical Model

    PubMed Central

    Tao, Youlun; Ding, Maochao; Wang, Aiguo; Zhuang, Yuehong; Chang, Shi-Min; Mei, Jin; Hallock, Geoffrey G.

    2016-01-01

    Background: A mathematical model to help explain the hemodynamic characteristics of perforator flaps based on blood flow resistance systems within the flap will serve as a theoretical guide for the future study and clinical applications of these flaps. Methods: There are 3 major blood flow resistance network systems of a perforator flap. These were defined as the blood flow resistance of an anastomosis between artery and artery of adjacent perforasomes, between artery and vein within a perforasome, and then between vein and vein corresponding to the outflow of that perforasome. From this, a calculation could be made of the number of such blood flow resistance network systems that must be crossed for all perforasomes within a perforator flap to predict whether that arrangement would be viable. Results: The summation of blood flow resistance networks from each perforasome in a given perforator flap could predict which portions would likely survive. This mathematical model shows how this is directly dependent on the location of the vascular pedicle to the flap and whether supercharging or superdrainage maneuvers have been added. These configurations will give an estimate of the hemodynamic characteristics for the given flap design. Conclusions: This basic mathematical model can (1) conveniently determine the degree of difficulty for each perforasome within a perforator flap to survive; (2) semiquantitatively allow the calculation of basic hemodynamic parameters; and (3) allow the assessment of the pros and cons expected for each pattern of perforasomes encountered clinically based on predictable hemodynamic observations. PMID:27579238

  2. Arterialized Venous Bone Flaps: An Experimental Investigation

    PubMed Central

    Borumandi, Farzad; Higgins, James P.; Buerger, Heinz; Vasilyeva, Anna; Benlidayi, Memmet Emre; Sencar, Leman; Gaggl, Alexander

    2016-01-01

    In arterialized venous flaps (AVFs) the venous network is used to revascularize the flap. While the feasibility of AVFs in soft tissues has been reported there is no study on osseous AVFs. In this study we aim to assess the flap survival of osseous AVFs in a pig model. Medial femoral condyle flaps were elevated in 18 pigs. Three groups were created: AVF (n = 6), conventional arterial flap (cAF, n = 6) and bone graft (BG, n = 6). The AVFs were created by anastomosis of genicular artery with one vena comitans while leaving one efferent vein for drainage. After 6 months the specimens were harvested. The histology and histomorphometry of of the bone in cAF and AVF was significantly superior to bone grafts with a higher bone volume in AVFs (p = 0.01). This study demonstrates that osseous free flaps may be supported and survive using the technique of arterialization of the venous network. The concept of AVFs in osseous flaps may be feasible for revascularization of free flaps with an inadequate artery but well developed veins. Further experimental and clinical studies are needed to assess the feasibility of clinical use of arterialized venous bone flaps. PMID:27558705

  3. [The super extended sub-mental flap or combo sub-mental flap].

    PubMed

    Martin, D

    2014-08-01

    The author presents a technical variation of the sub-mental flap including in a conventional pedicled flap both sub-mental axes and their anastomoses on the midline. The assessment of the first flaps raised according to this method confirms the improvement of the distal blood supply. It allows the possibility to harvest "super extended" flaps reaching the contralateral auricular lobula. This variation can be considered as an axial flap which only the tip, located beyond the mandibular angle, is at random. The evolution of the sub-mental flap from its original description to this variation called "combo sub-mental flap" is then presented. Its reliability and the technical simplification it provides will have to be assessed in the future. PMID:24840945

  4. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  5. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  6. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  7. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  8. 14 CFR 25.457 - Wing flaps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing flaps. 25.457 Section 25.457 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.457 Wing flaps....

  9. Piezoelectrically actuated insect scale flapping wing

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sujoy; Ganguli, Ranjan

    2010-04-01

    An energy method is used in order to derive the non-linear equations of motion of a smart flapping wing. Flapping wing is actuated from the root by a PZT unimorph in the piezofan configuration. Dynamic characteristics of the wing, having the same size as dragonfly Aeshna Multicolor, are analyzed using numerical simulations. It is shown that flapping angle variations of the smart flapping wing are similar to the actual dragonfly wing for a specific feasible voltage. An unsteady aerodynamic model based on modified strip theory is used to obtain the aerodynamic forces. It is found that the smart wing generates sufficient lift to support its own weight and carry a small payload. It is therefore a potential candidate for flapping wing of micro air vehicles.

  10. Scrubbing noise of externally blown flaps

    NASA Technical Reports Server (NTRS)

    Fink, M. R.

    1975-01-01

    An experimental study was conducted to examine the aeroacoustic mechanism that produces externally blown flap (EBF) scrubbing noise, i.e. a surface-radiated noise which is generally strongest normal to UTW deflected flaps. Scrubbing noise was not radiated from portions of the surface adjacent to strong, locally coherent turbulent eddies. Instead, scrubbing noise seemed to come from weak loading fluctuations that were coherent along the scrubbed span. These loading fluctuations probably were induced by the convected large-scale vortex structure of the attached exhaust jet. Deflecting a UTW flap would reduce the distance between the vortex trajectory and the flap surface, increasing the resulting dipole noise and rotating its directivity. In contrast, deflecting a USB flap would increase this distance, so that observable scrubbing noise would be radiated only from the undeflected forward portion of the wing.

  11. Facial artery flaps in facial oncoplastic reconstruction.

    PubMed

    Fabrizio, Tommaso

    2013-10-01

    The face is one of the common sites for cutaneous cancer localization. It is well known that the face is the localization of more than 50% of skin cancers. Nowadays, the principles of modern "oncoplasty" recommend the complete excision of the cancer and the reconstruction with respect to cosmetic features of the face in terms of good color, good softness, and good texture of the flaps, utilized in cancer repair. The oncological and cosmetic results of facial reconstruction are strictly linked and the modern plastic and reconstructive surgeon must respect both oncological and cosmetic aspects. For that reason the best solution in facial cancer repair is the utilization of locoregional flaps based on the tributary vessels of the facial artery. In consideration of the dimension of recipient area to repair, the retroangular flap (RAF) or the submental flap could be used. This article is voted to illustrate a very large and long-term casuistry dedicated to these flaps.

  12. Hydrodynamic schooling of flapping swimmers

    DOE PAGES

    Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.; Shelley, Michael; Ristroph, Leif

    2015-10-06

    Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing–wake interactions. Simulations show that swimming in amore » group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. Lastly, these results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups.« less

  13. Hydrodynamic schooling of flapping swimmers

    SciTech Connect

    Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.; Shelley, Michael; Ristroph, Leif

    2015-10-06

    Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing–wake interactions. Simulations show that swimming in a group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. Lastly, these results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups.

  14. Hydrodynamic schooling of flapping swimmers

    PubMed Central

    Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.; Shelley, Michael; Ristroph, Leif

    2015-01-01

    Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing–wake interactions. Simulations show that swimming in a group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. These results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups. PMID:26439509

  15. Hydrodynamic schooling of flapping swimmers

    NASA Astrophysics Data System (ADS)

    Becker, Alexander D.; Masoud, Hassan; Newbolt, Joel W.; Shelley, Michael; Ristroph, Leif

    2015-10-01

    Fish schools and bird flocks are fascinating examples of collective behaviours in which many individuals generate and interact with complex flows. Motivated by animal groups on the move, here we explore how the locomotion of many bodies emerges from their flow-mediated interactions. Through experiments and simulations of arrays of flapping wings that propel within a collective wake, we discover distinct modes characterized by the group swimming speed and the spatial phase shift between trajectories of neighbouring wings. For identical flapping motions, slow and fast modes coexist and correspond to constructive and destructive wing-wake interactions. Simulations show that swimming in a group can enhance speed and save power, and we capture the key phenomena in a mathematical model based on memory or the storage and recollection of information in the flow field. These results also show that fluid dynamic interactions alone are sufficient to generate coherent collective locomotion, and thus might suggest new ways to characterize the role of flows in animal groups.

  16. Aerodynamic characteristics of a wing with Fowler flaps including flap loads, downwash, and calculated effect on take-off

    NASA Technical Reports Server (NTRS)

    Platt, Robert C

    1936-01-01

    This report presents the results of wind tunnel tests of a wing in combination with each of three sizes of Fowler flap. The purpose of the investigation was to determine the aerodynamic characteristics as affected by flap chord and position, the air loads on the flaps, and the effect of flaps on the downwash.

  17. TRAM flap breast reconstruction after radiation treatment.

    PubMed Central

    Williams, J K; Bostwick, J; Bried, J T; Mackay, G; Landry, J; Benton, J

    1995-01-01

    OBJECTIVE: Patients with and without radiation treatment before their breast reconstruction were compared to study the relationship of radiation to flap-related complications. SUMMARY BACKGROUND DATA: The transverse rectus abdominis muscle (TRAM) flap for breast reconstruction involves a a vascular pedicle and recipient bed, both included in the radiated field of patients undergoing adjunctive therapy. Detailed reviews of flap-related complications in this subgroup of patients have been limited. METHODS: One hundred eight patients with radiation treatment who subsequently underwent a TRAM flap breast reconstruction were compared with 572 patients with no radiation treatment before similar reconstruction. Flap-related complications, radiation dosage, time, fields, relationships between risk factors, and complications were studied. RESULTS: Overall complication rates were comparable between the two groups. Only fat necrosis (> 10% of total reconstruction) was found to be statistically significant (17.6% vs. 10.1%, p = 0.03228). No difference was found for fat necrosis in unipedicled vs. bipedicled flaps controlled for radiation (17.7% vs. 17.4%). Obesity and radiation therapy were associated with fat necrosis and major infection in a logistic regression. Significant abdominal scarring was also associated with major infection (p = 0.0044). CONCLUSIONS: In this, the largest reported series, radiation therapy was associated with increased fat necrosis and major infection. The use of the TRAM flap was not found to be prohibitive in radiated patients and should still be the first choice in this subgroup of patients. Images Figure 1. Figure 2. PMID:7794079

  18. Preputial flaps to correct buried penis.

    PubMed

    Chu, Chih-Chun; Chen, Yi-Hsin; Diau, Guan-Yeu; Loh, Ih-Wei; Chen, Ke-Chi

    2007-11-01

    The authors developed a preputial skin flap technique to correct the buried penis which was simple and practical. This simple procedure can be applied to most boys with buried penis. In the last 3 years, we have seen 12 boys with buried penis and have been treated by using preputial flaps. The mean age is about 5.1 (from 3 to 12). By making a longitudinal incision on the ventral side of penis, the tightness of the foreskin is released and leave a diamond-shaped skin defect. It allows the penile shaft to extend out. A circumferential incision is made about 5 mm proximal to the coronal sulcus. Pedicled preputial flaps are obtained leaving optimal penile skin on the dorsal side. The preputial skin flaps are rotated onto the ventral side and tailored to cover the defect. All patients are followed for at least 3 months. Edema and swelling on the flaps are common, but improves with time. None of our patients need a second operation. The preputial flaps technique is a simple technique which allows surgeons to deal with most cases of buried penis by tailoring the flaps providing good cosmetic and functional results.

  19. Critical Mach Numbers of Thin Airfoil Sections with Plain Flaps

    NASA Technical Reports Server (NTRS)

    Pardee, Otway O'm.; Heaslet, Max A.

    1946-01-01

    Critical Mach number as function of lift coefficient is determined for certain moderately thick NACA low-drag airfoils. Results, given graphically, included calculations on same airfoil sections with plain flaps for small flap deflections. Curves indicate optimum critical conditions for airfoils with flaps in such form that they can be compared with corresponding results for zero flap deflections. Plain flaps increase life-coefficient range for which critical Mach number is in region of high values characteristic of low-drag airfoils.

  20. Pedicled Supraclavicular Artery Island Flap Versus Free Radial Forearm Flap for Tongue Reconstruction Following Hemiglossectomy.

    PubMed

    Zhang, Senlin; Chen, Wei; Cao, Gang; Dong, Zhen

    2015-09-01

    This study investigated the tongue function and donor-site morbidity of patients with malignant tumors who had undergone immediate flap reconstruction surgery. Twenty-seven patients who had undergone immediate reconstruction after hemiglossectomy were observed. Twelve patients were reconstructed using the pedicled supraclavicular artery island flap (PSAIF) and 15 patients using the free radial forearm flap (FRFF). Flap survival, speech and swallowing function, and donor-site morbidity at the 6-month follow-up were evaluated. All the flaps were successfully transferred. No obvious complications were found in either the transferred flaps or donor regions. Age, sex, defect extent, speech and swallowing function were comparable between the 2 groups. Donor-site complications were less frequent with PSAIF reconstruction than FRFF reconstruction. The PSAIF is reliable and well suited for hemiglossectomy defect. It has few significant complications, and allows preservation of oral function.

  1. On the generation of side-edge flap noise. [part span trailing edge flaps

    NASA Technical Reports Server (NTRS)

    Howe, M. S.

    1981-01-01

    A theory is proposed for estimating the noise generated at the side edges of part span trailing edge flaps in terms of pressure fluctuations measured just in-board of the side edge of the upper surface of the flap. Asymptotic formulae are developed in the opposite extremes of Lorentz contracted acoustic wavelength large/small compared with the chord of the flap. Interpolation between these limiting results enables the field shape and its dependence on subsonic forward flight speed to be predicted over the whole frequency range. It is shown that the mean width of the side edge gap between the flap and the undeflected portion of the airfoil has a significant influence on the intensity of the radiated sound. It is estimated that the noise generated at a single side edge of a full scale part span flap can exceed that produced along the whole of the trailing edge of the flap by 3 dB or more.

  2. A review of propeller flaps for distal lower extremity soft tissue reconstruction: Is flap loss too high?

    PubMed

    Nelson, Jonas A; Fischer, John P; Brazio, Philip S; Kovach, Stephen J; Rosson, Gedge D; Rad, Ariel N

    2013-10-01

    Soft tissue coverage in the distal lower extremity remains a significant challenge. While free flaps are often utilized for larger defects, local perforator-based propeller flaps may be ideal for smaller wounds requiring coverage. Propeller flaps can provide excellent form and function for both traumatic and atraumatic defects with minimal donor site morbidity but can have concerning rates of flap loss. We reviewed the literature, identifying 21 studies presenting 310 propeller flaps for distal lower extremity reconstruction. Total flap necrosis was noted in 5.5% of flaps, with partial necrosis in 11.6%. While these flaps do enable transfer of local, healthy tissue to the defect site without the need for a microsurgical anastomosis, this rate of flap loss is concerning and appropriate patient selection is crucial. This review provides a brief history and overview of the clinical application and research into distal lower extremity perforator propeller flaps to place this technique into a clinical context.

  3. The plane problem of the flapping wing

    NASA Technical Reports Server (NTRS)

    Birnbaum, Walter

    1954-01-01

    In connection with an earlier report on the lifting vortex sheet which forms the basis of the following investigations this will show how the methods developed there are also suitable for dealing with the air forces for a wing with a circulation variable with time. The theory of a propulsive wing flapping up and down periodically in the manner of a bird's wing is developed. This study shows how the lift and its moment result as a function of the flapping motion, what thrust is attainable, and how high is the degree of efficiency of this flapping propulsion unit if the air friction is disregarded.

  4. Flap-augmented shrouds for aerogenerators

    NASA Technical Reports Server (NTRS)

    Seginer, A.

    1976-01-01

    Axisymmetrical shrouds for windmills are augmented by ring-shaped 'flaps' and their performance is studied experimentally. The concept of the shroud as an annular 'wing' is justified, leading to the conclusion that high-lift techniques should be used in shroud design, and that high-lift devices, such as flaps, would increase the power output of the windmill. It is shown experimentally that the ideal power output of a flap-augmented shrouded turbine can be more than 4 times the power of unshrouded turbines of the same diameter.

  5. Dynamic response of a piezoelectric flapping wing

    NASA Astrophysics Data System (ADS)

    Kumar, Alok; Khandwekar, Gaurang; Venkatesh, S.; Mahapatra, D. R.; Dutta, S.

    2015-03-01

    Piezo-composite membranes have advantages over motorized flapping where frequencies are high and certain coupling between bending and twisting is useful to generate lift and forward flight. We draw examples of fruit fly and bumble bee. Wings with Piezo ceramic PZT coating are realized. The passive mechanical response of the wing is characterized experimentally and validated using finite element simulation. Piezoelectric actuation with uniform electrode coating is characterized and optimal frequencies for flapping are identified. The experimental data are used in an empirical model and advanced ratio for a flapping insect like condition for various angular orientations is estimated.

  6. Propeller Flap Reconstruction in Post Oncological Thigh Defect: "The Move in Flap".

    PubMed

    Nambi, G I; Salunke, Abhijeet Ashok

    2015-06-01

    Reconstruction of soft tissue defects of the limb after tumor resection is challenging question for oncosurgeons. The management differs from reconstruction of post traumatic defects due to the complexity of the primary surgery and subsequent radiation. The conventional propeller flap is based on a perforator which is located close to the defect; but in present case the perforator was located far away from the defect. So we describe it as "Move in flap" as the flap rotated a large volume of soft tissue lying between the defect and the perforator. We present a case of post oncological thigh defect with reconstruction using a propeller flap based on distal anteromedial perforator.

  7. Foot and ankle reconstruction: an experience on the use of 14 different flaps in 226 cases.

    PubMed

    Zhu, Yue-Liang; Wang, Yi; He, Xiao-Qing; Zhu, Min; Li, Fu-Bin; Xu, Yong-Qing

    2013-11-01

    The aim of this report was to present our experience on the use of different flaps for soft tissue reconstruction of the foot and ankle. From 2007 to 2012, the soft tissue defects of traumatic injuries of the foot and ankle were reconstructed using 14 different flaps in 226 cases (162 male and 64 female). There were 62 pedicled flaps and 164 free flaps used in reconstruction. The pedicled flaps included sural flap, saphenous flap, dorsal pedal neurocutaneous flap, pedicled peroneal artery perforator flap, pedicled tibial artery perforator flap, and medial plantar flap. The free flaps were latissimus musculocutaneous flap, anterolateral thigh musculocutaneous flap, groin flap, lateral arm flap, anterolateral thigh perforator flap, peroneal artery perforator flap, thoracdorsal artery perforator flap, medial arm perforator flap. The sensory nerve coaptation was not performed for all of flaps. One hundred and ninety-four cases were combined with open fractures. One hundred and sixty-two cases had tendon. Among 164 free flaps, 8 flaps were completely lost, in which the defects were managed by the secondary procedures. Among the 57 flaps for plantar foot coverage (25 pedicled flaps and 32 free flaps), ulcers were developed in 5 pedicled flaps and 6 free flaps after weight bearing, and infection was found in 14 flaps. The donor site complications were seen in 3 cases with the free anterolateral thigh perforator flap transfer. All of limbs were preserved and the patients regained walking and daily activities. All of patients except for one regained protective sensation from 3 to 12 months postoperatively. Our experience showed that the sural flap and saphenous flap could be good options for the coverage of the defects at malleolus, dorsal hindfoot and midfoot. Plantar foot, forefoot and large size defects could be reconstructed with free anterolateral thigh perforator flap. For the infected wounds with dead spce, the free latissimus dorsi musculocutaneous flap remained to

  8. Route Flap Damping Made Usable

    NASA Astrophysics Data System (ADS)

    Pelsser, Cristel; Maennel, Olaf; Mohapatra, Pradosh; Bush, Randy; Patel, Keyur

    The Border Gateway Protocol (BGP), the de facto inter-domain routing protocol of the Internet, is known to be noisy. The protocol has two main mechanisms to ameliorate this, MinRouteAdvertisementInterval (MRAI), and Route Flap Damping (RFD). MRAI deals with very short bursts on the order of a few to 30 seconds. RFD deals with longer bursts, minutes to hours. Unfortunately, RFD was found to severely penalize sites for being well-connected because topological richness amplifies the number of update messages exchanged. So most operators have disabled it. Through measurement, this paper explores the avenue of absolutely minimal change to code, and shows that a few RFD algorithmic constants and limits can be trivially modified, with the result being damping a non-trivial amount of long term churn without penalizing well-behaved prefixes' normal convergence process.

  9. Mucocele formation under pedicled nasoseptal flap.

    PubMed

    Vaezeafshar, Reza; Hwang, Peter H; Harsh, Griffith; Turner, Justin H

    2012-01-01

    The pedicled nasoseptal flap has become an indispensible tool for the reconstruction of skull base defects. This flap is easily harvested, provides a large surface area of vascularized tissue, and has few reported complications. We describe the case of a 60-year-old man who underwent endoscopic, endonasal transsphenoidal surgery with septal flap reconstruction who developed a sphenoid sinus mucocele postoperatively. We also have reviewed the literature for similar findings and discuss this complication in the setting of pituitary surgery and endoscopic skull base repair. Although likely a rare occurrence, mucocele formation after septal flap reconstruction should be recognized and monitored with postoperative nasal endoscopy and radiologic imaging. Reoperation or mucocele drainage may be necessary if symptomatic or in cases of rapid enlargement.

  10. Postirradiation flap infection about the oral cavity

    SciTech Connect

    Cabbabe, E.B.; Herbold, D.R.; Sunwoo, Y.C.; Baroudi, I.F.

    1983-06-01

    Postirradiation alteration of oral flora is well documented in the literature. Infection as a complication leading to partial or complete loss of a flap used to reconstruct a defect in the oral cavity is a worrisome outcome. We describe how a flap that was judged clinically to be viable became overwhelmingly infected with the Klebsiella oxytoca, an oral cavity pathogen encountered in this patient following irradiation. Local and systemic changes led to detachment of the flap. This complication may be explained, in view of the absence of venous congestion or arterial ischemia both clinically and pathologically, by the proven contamination of the flap by the Klebsiella pathogen. Local factors resulted in lower resistance and subsequent overwhelming infection. Discussion of the case, review of pertinent literature, and proposed solutions are presented.

  11. A dynamical system for interacting flapping swimmers

    NASA Astrophysics Data System (ADS)

    Oza, Anand; Ramananarivo, Sophie; Ristroph, Leif; Shelley, Michael

    2015-11-01

    We present the results of a theoretical investigation into the dynamics of interacting flapping swimmers. Our study is motivated by the recent experiments of Becker et al., who studied a one-dimensional array of self-propelled flapping wings that swim within each other's wakes in a water tank. They discovered that the system adopts certain ``schooling modes'' characterized by specific spatial phase relationships between swimmers. To rationalize these phenomena, we develop a discrete dynamical system in which the swimmers are modeled as heaving airfoils that shed point vortices during each flapping cycle. We then apply our model to recent experiments in the Applied Math Lab, in which two tandem flapping airfoils are free to choose both their speed and relative positions. We expect that our model may be used to understand how schooling behavior is influenced by hydrodynamics in more general contexts. Thanks to the NSF for its support.

  12. Interpreting laser Doppler recordings from free flaps.

    PubMed

    Svensson, H; Holmberg, J; Svedman, P

    1993-01-01

    Although the transfer of free flaps is nowadays accomplished with an increasing degree of safety, thrombosis of the microvascular anastomoses is still a problem. In order to avoid delay in re-operating, various methods for objective blood flow monitoring have been tried, among them Laser Doppler Flowmetry (LDF). When one reviews the literature, it is apparent that opinions differ about whether or not LDF is a reliable technique for this purpose. To focus on the need to interpret continuous recordings, this paper reports our findings in six latissimus dorsi free flaps chosen from our series of LDF monitoring procedures. One uneventful flap, no. 1, had an immediate postoperative LDF value of 4.5 perfusion units (PU). LDF values improved during the recovery period and the graphic recording showed fluctuations due to normal physiological variations of the blood flow in the flap. Another uneventful flap, no. 4, showed the same pattern, though at an appreciably lower level, 2 PU, on average. Flap no. 2 had an acceptably high value of 3.5 PU despite suffering a venous thrombosis. However, the LDF recording showed no fluctuations and the value declined gradually. Another flap, no. 3, showed fluctuations and blood flow was normal although the value decreased to 2.5 PU. In flap no. 5, any value between 2 and 3.5 PU could be obtained merely by adjusting the position of the probe in the holder. In no. 6, the LDF value suddenly dropped, accompanied by a decrease in the total amount of backscattered light, indicating venous obstruction which was confirmed at re-operation.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Extending the extended V-Y flap.

    PubMed

    Prowse, Phoebe; Morton, Jonathan

    2012-06-01

    This case report demonstrates a modification of the so-called 'Extended V-Y Flap' used to simultaneously reconstruct a defect involving the upper lip, floor of nose and alar rim following tumour excision. We hope that this case serves as a reminder of the versatility of the V-Y flap in the nasolabial region, and its considerable capacity for augmentation. PMID:22018837

  14. The origin of the temporalis muscle flap.

    PubMed

    Speculand, B

    1992-12-01

    This paper explores the origin of the temporalis muscle flap which has been attributed to Golovine, a Moscow ophthalmic surgeon, who described a forehead skin transposition flap. Small temporalis muscle transpositions were used in surgery for TMJ ankylosis, but the use of the majority of the muscle for reconstruction of facial defects was first described by Sir Harold Gillies during the 1914-18 war.

  15. Aerodynamic effects of flexibility in flapping wings.

    PubMed

    Zhao, Liang; Huang, Qingfeng; Deng, Xinyan; Sane, Sanjay P

    2010-03-01

    Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast, wings flapping at high angles of attack generate stable leading edge vorticity, which persists throughout the duration of the stroke and enhances mean aerodynamic forces. Here, we show that aerodynamic forces can be controlled by altering the trailing edge flexibility of a flapping wing. We used a dynamically scaled mechanical model of flapping flight (Re approximately 2000) to measure the aerodynamic forces on flapping wings of variable flexural stiffness (EI). For low to medium angles of attack, as flexibility of the wing increases, its ability to generate aerodynamic forces decreases monotonically but its lift-to-drag ratios remain approximately constant. The instantaneous force traces reveal no major differences in the underlying modes of force generation for flexible and rigid wings, but the magnitude of force, the angle of net force vector and centre of pressure all vary systematically with wing flexibility. Even a rudimentary framework of wing veins is sufficient to restore the ability of flexible wings to generate forces at near-rigid values. Thus, the magnitude of force generation can be controlled by modulating the trailing edge flexibility and thereby controlling the magnitude of the leading edge vorticity. To characterize this, we have generated a detailed database of aerodynamic forces as a function of several variables including material properties, kinematics, aerodynamic forces and centre of pressure, which can also be used to help validate computational models of aeroelastic flapping wings. These experiments will also be useful for wing design for small

  16. Aerodynamic effects of flexibility in flapping wings

    PubMed Central

    Zhao, Liang; Huang, Qingfeng; Deng, Xinyan; Sane, Sanjay P.

    2010-01-01

    Recent work on the aerodynamics of flapping flight reveals fundamental differences in the mechanisms of aerodynamic force generation between fixed and flapping wings. When fixed wings translate at high angles of attack, they periodically generate and shed leading and trailing edge vortices as reflected in their fluctuating aerodynamic force traces and associated flow visualization. In contrast, wings flapping at high angles of attack generate stable leading edge vorticity, which persists throughout the duration of the stroke and enhances mean aerodynamic forces. Here, we show that aerodynamic forces can be controlled by altering the trailing edge flexibility of a flapping wing. We used a dynamically scaled mechanical model of flapping flight (Re ≈ 2000) to measure the aerodynamic forces on flapping wings of variable flexural stiffness (EI). For low to medium angles of attack, as flexibility of the wing increases, its ability to generate aerodynamic forces decreases monotonically but its lift-to-drag ratios remain approximately constant. The instantaneous force traces reveal no major differences in the underlying modes of force generation for flexible and rigid wings, but the magnitude of force, the angle of net force vector and centre of pressure all vary systematically with wing flexibility. Even a rudimentary framework of wing veins is sufficient to restore the ability of flexible wings to generate forces at near-rigid values. Thus, the magnitude of force generation can be controlled by modulating the trailing edge flexibility and thereby controlling the magnitude of the leading edge vorticity. To characterize this, we have generated a detailed database of aerodynamic forces as a function of several variables including material properties, kinematics, aerodynamic forces and centre of pressure, which can also be used to help validate computational models of aeroelastic flapping wings. These experiments will also be useful for wing design for small robotic

  17. Investigation of Energy Harvesting Using Flapping Foils

    NASA Astrophysics Data System (ADS)

    Mivehchi, Amin; Persichetti, Amanda; Dunham, Brandon; Dahl, Jason M.

    2013-11-01

    When harvesting kinetic energy using a flapping foil, the separation of coherent structures in the wake is crucial for determining forces on the body. Applications for utilizing energy harvesting with a flapping foil include powering of local, low power equipment and recharging AUV batteries that use flapping foils for propulsion and maneuvering. In each of these cases, it is critical to accurately predict the physical behavior and location of vortices in relation to the motion of the body in order to maximize energy output. A two-dimensional open source boundary data immersion method (LilyPad) is used for simulating the flapping motion of a foil for energy harvesting in a current. Forced motion of the flapping body indicates theoretical efficiencies for energy harvesting near 43 percent under specific flapping conditions. A simple control scheme based on pressure sensing on the surface of the foil is developed to control pitch of the foil while energy harvesting occurs in the heave direction. The control scheme is tested through real time numerical simulation. Comparisons are made with physical laboratory experiments, demonstrating high efficiencies in energy harvesting.

  18. The dog-ear flap as an alternative for breast reconstruction in patients who have already undergone a DIEAP flap.

    PubMed

    Colebunders, Britt; Depypere, Bernard; Van Landuyt, Koenraad

    2016-05-01

    Breast reconstruction in patients who have previously undergone deep inferior epigastric artery perforator flap (DIEAP) reconstruction or abdominoplasty is often challenging. Depending on patients' body habitus, several second-choice flaps have been described such as the transverse upper gracilis (TUG) flap, profundus femoris artery perforator (PFAP) flap, superior gluteal artery perforator (SGAP) flap, and lumbar artery perforator (LAP) flap. Patients who have undergone a DIEAP flap reconstruction or abdominoplasty occasionally present with dog ears on both sides of the abdominal scar. The adipose tissue and skin of these dog ears are supplied by perforators of the deep circumflex iliac artery (DCIA). The DCIA flap was first described in 1979 by Taylor. We introduce this abdominal "dog-ear" flap for autologous breast reconstruction. PMID:26951847

  19. Comparing semilunar coronally positioned flap to standard coronally positioned flap using periodontal clinical parameters.

    PubMed

    Nassar, Carlos Augusto; da Silva, Wilson Aparecido Dias; Tonet, Karine; Secundes, Mayron Barros; Nassar, Patricia Oehlmeyer

    2014-01-01

    This study compared the effectiveness of 2 surgical root coverage techniques--semilunar coronally positioned flap and coronally advanced flap--using the clinical parameters of periodontal tissues from patients with Miller Class I gingival recession. Twenty patients (20-50 years of age) were selected. Basic periodontal treatment was performed, and plaque index, gingival index, probing depth, clinical attachment level, and height of the attached gingiva were determined. Each patient was placed into 1 of 2 groups: Group 1 patients underwent the semilunar coronally positioned flap technique, and Group 2 patients underwent the coronally advanced flap technique. Patients were assessed for 180 days. Both groups showed significant reduction of plaque and gingival indices and an improvement in clinical attachment levels and probing depth. However, results showed the standard coronally positioned flap technique was deemed more effective due to significant clinical attachment level gains. PMID:24598495

  20. Aerodynamic flight performance in flap-gliding birds and bats.

    PubMed

    Muijres, Florian T; Henningsson, Per; Stuiver, Melanie; Hedenström, Anders

    2012-08-01

    Many birds use a flight mode called undulating or flap-gliding flight, where they alternate between flapping and gliding phases, while only a few bats make use of such a flight mode. Among birds, flap-gliding is commonly used by medium to large species, where it is regarded to have a lower energetic cost than continuously flapping flight. Here, we introduce a novel model for estimating the energetic flight economy of flap-gliding animals, by determining the lift-to-drag ratio for flap-gliding based on empirical lift-to-drag ratio estimates for continuous flapping flight and for continuous gliding flight, respectively. We apply the model to flight performance data of the common swift (Apus apus) and of the lesser long-nosed bat (Leptonycteris yerbabuenae). The common swift is a typical flap-glider while-to the best of our knowledge-the lesser long-nosed bat does not use flap-gliding. The results show that, according to the model, the flap-gliding common swift saves up to 15% energy compared to a continuous flapping swift, and that this is primarily due to the exceptionally high lift-to-drag ratio in gliding flight relative to that in flapping flight for common swifts. The lesser long-nosed bat, on the other hand, seems not to be able to reduce energetic costs by flap-gliding. The difference in relative costs of flap-gliding flight between the common swift and the lesser long-nosed bat can be explained by differences in morphology, flight style and wake dynamics. The model presented here proves to be a valuable tool for estimating energetic flight economy in flap-gliding animals. The results show that flap-gliding flight that is naturally used by common swifts is indeed the most economic one of the two flight modes, while this is not the case for the non-flap-gliding lesser long-nosed bat.

  1. Extended thoracodorsal artery perforator flap for breast reconstruction.

    PubMed

    Angrigiani, Claudio; Rancati, Alberto; Escudero, Ezequiel; Artero, Guillermo

    2015-12-01

    A total of 45 patients underwent partial or total autologous breast reconstruction after skin-sparing mastectomy, skin-reducing mastectomy, and quadrantectomy using a thoracodorsal artery perforator (TDAP) flap. The detailed surgical technique with its variations is explained in this report. The propeller, flip-over, conventional perforator, and muscle-sparing flaps have been described and evaluated. The flaps were partially or completely de-epithelialized. The conventional TDAP can be enlarged or "extended" as the traditional latissimus dorsi musculocutaneous (LD-MC) flap by incorporating the superior and inferior fat compartments. It can be referred to as the "extended TDAP flap". This technique augments the flap volume. In addition, this flap can serve as a scaffold for lipofilling to obtain autologous breast reconstruction in medium to large cases. There were two complete failures due to technical errors during flap elevation. Distal partial tissue suffering was observed in four flaps. These flaps were longer than usual; they reached the midline of the back. It is advisable to discard the distal medial quarter of the flap when it is designed up to the midline to avoid steatonecrosis or fibrosis. A retrospective analysis of the 39 flaps that survived completely revealed a satisfactory result in 82% of the cases. The main disadvantage of this procedure is the final scar. The TDAP flap is a reliable and safe method for partial or total breast autologous reconstruction. PMID:26645006

  2. Flow field of flexible flapping wings

    NASA Astrophysics Data System (ADS)

    Sallstrom, Erik

    The agility and maneuverability of natural fliers would be desirable to incorporate into engineered micro air vehicles (MAVs). However, there is still much for engineers to learn about flapping flight in order to understand how such vehicles can be built for efficient flying. The goal of this study is to develop a methodology for capturing high quality flow field data around flexible flapping wings in a hover environment and to interpret it to gain a better understanding of how aerodynamic forces are generated. The flow field data was captured using particle image velocimetry (PIV) and required that measurements be taken around a repeatable flapping motion to obtain phase-averaged data that could be studied throughout the flapping cycle. Therefore, the study includes the development of flapping devices with a simple repeatable single degree of freedom flapping motion. The acquired flow field data has been examined qualitatively and quantitatively to investigate the mechanisms behind force production in hovering flight and to relate it to observations in previous research. Specifically, the flow fields have been investigated around a rigid wing and several carbon fiber reinforced flexible membrane wings. Throughout the whole study the wings were actuated with either a sinusoidal or a semi-linear flapping motion. The semi-linear flapping motion holds the commanded angular velocity nearly constant through half of each half-stroke while the sinusoidal motion is always either accelerating or decelerating. The flow fields were investigated by examining vorticity and vortex structures, using the Q criterion as the definition for the latter, in two and three dimensions. The measurements were combined with wing deflection measurements to demonstrate some of the key links in how the fluid-structure interactions generated aerodynamic forces. The flow fields were also used to calculate the forces generated by the flapping wings using momentum balance methods which yielded

  3. Deltopectoral Flap in the Era of Microsurgery

    PubMed Central

    Chan, R. C. L.; Chan, J. Y. W.

    2014-01-01

    Background. Our study aimed to review the role of deltopectoral (DP) flap as a reconstructive option for defects in the head and neck region in the microvascular era. Methods. All patients who received DP flap reconstruction surgery at the Department of Surgery, Queen Mary Hospital, between 1999 and 2011 were recruited. Demographic data, indications for surgery, defect for reconstruction, and surgical outcomes were analyzed. Results. Fifty-four patients were included. All but two patients were operated for reconstruction after tumour resection. The remaining two patients were operated for necrotizing fasciitis and osteoradionecrosis. The majority of DP flaps were used to cover neck skin defect (63.0%). Other reconstructed defects included posterior pharyngeal wall (22.2%), facial skin defect (11.1%), and tracheal wall (3.7%). All donor sites were covered with partial thickness skin graft. Two patients developed partial flap necrosis at the tip and were managed conservatively. The overall flap survival rate was 96.3%. Conclusions. Albeit the technical advancements in microvascular surgery, DP still possesses multiple advantages (technical simplicity, reliable axial blood supply, large size, thinness, and pliability) which allows it to remain as a useful, reliable, and versatile surgical option for head and neck reconstruction. PMID:25374953

  4. 14 CFR 25.1511 - Flap extended speed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flap extended speed. 25.1511 Section 25... Limitations § 25.1511 Flap extended speed. The established flap extended speed V FE must be established so that it does not exceed the design flap speed V F chosen under §§ 25.335(e) and 25.345, for...

  5. 14 CFR 25.1511 - Flap extended speed.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flap extended speed. 25.1511 Section 25... Limitations § 25.1511 Flap extended speed. The established flap extended speed V FE must be established so that it does not exceed the design flap speed V F chosen under §§ 25.335(e) and 25.345, for...

  6. 14 CFR 25.1511 - Flap extended speed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flap extended speed. 25.1511 Section 25... Limitations § 25.1511 Flap extended speed. The established flap extended speed V FE must be established so that it does not exceed the design flap speed V F chosen under §§ 25.335(e) and 25.345, for...

  7. 14 CFR 25.1511 - Flap extended speed.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flap extended speed. 25.1511 Section 25... Limitations § 25.1511 Flap extended speed. The established flap extended speed V FE must be established so that it does not exceed the design flap speed V F chosen under §§ 25.335(e) and 25.345, for...

  8. 14 CFR 25.1511 - Flap extended speed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flap extended speed. 25.1511 Section 25... Limitations § 25.1511 Flap extended speed. The established flap extended speed V FE must be established so that it does not exceed the design flap speed V F chosen under §§ 25.335(e) and 25.345, for...

  9. Calculation of the longitudinal aerodynamic characteristics of wing-flap configurations with externally blown flaps

    NASA Technical Reports Server (NTRS)

    Mendenhall, M. R.; Spangler, S. B.; Nielsen, J. N.; Goodwin, F. K.

    1976-01-01

    A theoretical investigation was carried out to extend and improve an existing method for predicting the longitudinal characteristics of wing flap configurations with externally blown flaps (EBF). Two potential flow models were incorporated into the prediction method: a wing and flap lifting-surface model and a turbofan engine wake model. The wing-flap model uses a vortex-lattice approach to represent the wing and flaps. The jet wake model consists of a series of closely spaced vortex rings normal to a centerline which may have vertical and lateral curvature to conform to the local flow field beneath the wing and flaps. Comparisons of measured and predicted pressure distributions, span load distributions on each lifting surface, and total lift and pitching moment coefficients on swept and unswept EBF configurations are included. A wide range of thrust coefficients and flap deflection angles is considered at angles of attack up to the onset of stall. Results indicate that overall lift and pitching-moment coefficients are predicted reasonably well over the entire range. The predicted detailed load distributions are qualitatively correct and show the peaked loads at the jet impingement points, but the widths and heights of the load peaks are not consistently predicted.

  10. Reconstruction of eyelids with Washio flap in anophthalmia.

    PubMed

    Tvrdek, M; Kozák, J

    2014-01-01

    The authors present a case report of a patient with anophthalmia in whom retroauriculo-temporal flap (Washio flap) was used for reconstruction of eyelids. This flap, which is mostly used for reconstructions of nasal defects, was not used in this way according to available literature.

  11. Flap Thickness in Eyes with Ectasia after LASIK

    PubMed Central

    Randleman, J. Bradley; Hebson, Carolyn B.; Larson, Paul M.

    2015-01-01

    Purpose To measure central flap thickness in eyes with ectasia after LASIK and to compare these values with estimated anticipated flap thickness based on average published values for each device used for flap creation. Setting Emory Vision at Emory University, Atlanta GA, USA Methods Confocal microscopic analysis using the Confoscan 3 (Nidek technologies) to measure central flap thickness in eyes with ectasia after LASIK, and evaluation of pre-LASIK records, including basic patient demographics, preoperative corneal topographies, estimated anticipated flap thickness based on published average thickness values, and residual stromal bed thickness (RSB) calculations using both measured and estimated flap thicknesses. Results Fifty eyes from 29 patients were evaluated. Average measured flap thickness was (138 ± 26 μ, range 90 to 220 μ). There were no significant differences between measured and estimated flap thicknesses (138 vs. 135 μ, p = 0.5) or RSB (329 vs. 332 μ, p = 0.7), nor were there any differences in flap thickness between eyes with normal or abnormal corneal topographies. Only one eye had a measured flap resulting in unintended RSB < 250 microns; this occurred in an eye with abnormal topography. Conclusions Measured central flap thickness was not thicker than estimated for the vast majority of eyes developing ectasia after LASIK. Thus, excessively thick flaps do not appear to be a major contributing factor to the pathogenesis of ectasia after LASIK. PMID:22424807

  12. The distally based forearm island flap in hand reconstruction.

    PubMed

    Jeng, S F; Wei, F C

    1998-08-01

    The distally based forearm island flap is vascularized by the perforators of the distal radial artery. The skin flap is along the axis of the radial artery, and the pivot point of its subcutaneous pedicle is about 2 to 4 cm above the radial styloid process. We have treated 12 patients with 12 flaps for soft-tissue defects of the hand. Of these recipient sites, seven were in dorsal hands, two were in thumbs, two were in forearms, and one was in the palmar area. The donor-tissue variants included eight skin flaps, two adipofascial flaps, and two sensate flaps. The sizes of the flaps ranged from 6 x 4 cm to 14 x 6 cm. The donor site wound could be closed primarily in five patients. Two sensate flaps, innervated by the lateral antebrachial cutaneous nerve, could provide sensation for thumb reconstruction. The advantage of this flap is its constant and reliable blood supply without sacrifice of the main radial artery. The elevation of the flap is simple and rapid. There is the potential that this flap can be used as an innervated flap, and there is no need of microsurgical technique.

  13. Sural Versus Perforator Flaps for Distal Medial Leg Wounds.

    PubMed

    Schannen, Andrew P; Truchan, Lisa; Goshima, Kaoru; Bentley, Roger; DeSilva, Gregory L

    2015-12-01

    Soft tissue coverage of distal medial ankle wounds is a challenging problem in orthopedic surgery because of the limited local tissues and prominent instrumentation. Traditionally, these wounds required free tissue transfer to achieve suitable coverage and subsequent bony union. To better respect the reconstructive ladder and to avoid the inherent difficulty of free flap coverage, rotational flaps have been used to cover these wounds. Both sural fasciocutaneous flaps and rotational fasciocutaneous perforator (propeller) flaps have been described for distal medial soft tissue coverage. The authors performed a retrospective chart review of patients who underwent distal medial leg coverage with the use of either sural flaps or rotational fasciocutaneous perforator flaps. The authors identified 14 patients by Current Procedural Terminology code who met the study criteria. The average age and degree of medical comorbidities were comparable in the 2 groups. The authors reviewed their medical records to evaluate fracture healing, flap size, complications, and return to normal shoe wear. All 7 sural flaps healed without incident, with underlying fracture healing. Of the 7 perforator flaps, 6 healed without incident, with underlying fracture healing. One perforator-based flap was complicated by superficial tip necrosis and went on to heal with local wound care. All patients returned to normal shoe wear. Both sural artery rotational flaps and posterior tibial artery-based rotational flaps are viable options for coverage of the distal medial leg. Coverage can be achieved reliably without microsurgery, anticoagulation, or monitoring in the intensive care unit. PMID:26652325

  14. 14 CFR 23.1511 - Flap extended speed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flap extended speed. 23.1511 Section 23.1511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Information § 23.1511 Flap extended speed. (a) The flap extended speed V FE must be established so that it...

  15. 14 CFR 23.1511 - Flap extended speed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flap extended speed. 23.1511 Section 23.1511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Information § 23.1511 Flap extended speed. (a) The flap extended speed V FE must be established so that it...

  16. 14 CFR 23.1511 - Flap extended speed.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flap extended speed. 23.1511 Section 23.1511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Information § 23.1511 Flap extended speed. (a) The flap extended speed V FE must be established so that it...

  17. 14 CFR 23.1511 - Flap extended speed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flap extended speed. 23.1511 Section 23.1511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Information § 23.1511 Flap extended speed. (a) The flap extended speed V FE must be established so that it...

  18. 14 CFR 23.1511 - Flap extended speed.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flap extended speed. 23.1511 Section 23.1511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Information § 23.1511 Flap extended speed. (a) The flap extended speed V FE must be established so that it...

  19. Posttraumatic eyebrow reconstruction with hair-bearing temporoparietal fascia flap.

    PubMed

    Denadai, Rafael; Raposo-Amaral, Cassio Eduardo; Marques, Frederico Figueiredo; Raposo-Amaral, Cesar Augusto

    2015-01-01

    The temporoparietal fascia flap has been extensively used in craniofacial reconstructions. However, its use for eyebrow reconstruction has been sporadically reported. We describe a successfully repaired hair-bearing temporoparietal fascia flap after traumatic avulsion of eyebrow. Temporoparietal fascia flap is a versatile tool and should be considered as a therapeutic option by all plastic surgeons.

  20. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  1. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  2. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  3. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  4. 14 CFR 23.699 - Wing flap position indicator.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing flap position indicator. 23.699 Section 23.699 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Construction Control Systems § 23.699 Wing flap position indicator. There must be a wing flap...

  5. Treatment of Ischial Pressure Sores with Both Profunda Femoris Artery Perforator Flaps and Muscle Flaps

    PubMed Central

    Kim, Chae Min; Yun, In Sik; Lee, Dong Won; Lew, Dae Hyun; Rah, Dong Kyun

    2014-01-01

    Background Reconstruction of ischial pressure sore defects is challenging due to extensive bursas and high recurrence rates. In this study, we simultaneously applied a muscle flap that covered the exposed ischium and large bursa with sufficient muscular volume and a profunda femoris artery perforator fasciocutaneous flap for the management of ischial pressure sores. Methods We retrospectively analyzed data from 14 patients (16 ischial sores) whose ischial defects had been reconstructed using both a profunda femoris artery perforator flap and a muscle flap between January 2006 and February 2014. We compared patient characteristics, operative procedure, and clinical course. Results All flaps survived the entire follow-up period. Seven patients (50%) had a history of surgery at the site of the ischial pressure sore. The mean age of the patients included was 52.8 years (range, 18-85 years). The mean follow-up period was 27.9 months (range, 3-57 months). In two patients, a biceps femoris muscle flap was used, while a gracilis muscle flap was used in the remaining patients. In four cases (25%), wound dehiscence occurred, but healed without further complication after resuturing. Additionally, congestion occurred in one case (6%), but resolved with conservative treatment. Among 16 cases, there was only one (6%) recurrence at 34 months. Conclusions The combination of a profunda femoris artery perforator fasciocutaneous flap and muscle flap for the treatment of ischial pressure sores provided pliability, adequate bulkiness and few long-term complications. Therefore, this may be used as an alternative treatment method for ischial pressure sores. PMID:25075362

  6. Numerical linearized MHD model of flapping oscillations

    NASA Astrophysics Data System (ADS)

    Korovinskiy, D. B.; Ivanov, I. B.; Semenov, V. S.; Erkaev, N. V.; Kiehas, S. A.

    2016-06-01

    Kink-like magnetotail flapping oscillations in a Harris-like current sheet with earthward growing normal magnetic field component Bz are studied by means of time-dependent 2D linearized MHD numerical simulations. The dispersion relation and two-dimensional eigenfunctions are obtained. The results are compared with analytical estimates of the double-gradient model, which are found to be reliable for configurations with small Bz up to values ˜ 0.05 of the lobe magnetic field. Coupled with previous results, present simulations confirm that the earthward/tailward growth direction of the Bz component acts as a switch between stable/unstable regimes of the flapping mode, while the mode dispersion curve is the same in both cases. It is confirmed that flapping oscillations may be triggered by a simple Gaussian initial perturbation of the Vz velocity.

  7. 50 CFR Figure 16 to Part 223 - Escape Opening and Flap Dimensions for the Double Cover Flap TED

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Escape Opening and Flap Dimensions for the Double Cover Flap TED 16 Figure 16 to Part 223 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE... AND ANADROMOUS SPECIES Pt. 223, Fig. 16 Figure 16 to Part 223—Escape Opening and Flap Dimensions...

  8. 50 CFR Figure 16 to Part 223 - Escape Opening and Flap Dimensions for the Double Cover Flap TED

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Escape Opening and Flap Dimensions for the Double Cover Flap TED 16 Figure 16 to Part 223 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE... AND ANADROMOUS SPECIES Pt. 223, Fig. 16 Figure 16 to Part 223—Escape Opening and Flap Dimensions...

  9. 50 CFR Figure 16 to Part 223 - Escape Opening and Flap Dimensions for the Double Cover Flap TED

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Escape Opening and Flap Dimensions for the Double Cover Flap TED 16 Figure 16 to Part 223 Wildlife and Fisheries NATIONAL MARINE FISHERIES... for the Double Cover Flap TED ER02JN04.003...

  10. 50 CFR Figure 16 to Part 223 - Escape Opening and Flap Dimensions for the Double Cover Flap TED

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Escape Opening and Flap Dimensions for the Double Cover Flap TED 16 Figure 16 to Part 223 Wildlife and Fisheries NATIONAL MARINE FISHERIES... for the Double Cover Flap TED ER02JN04.003...

  11. Airplane wing leading edge variable camber flap

    NASA Technical Reports Server (NTRS)

    Cole, J. B.

    1980-01-01

    The invention and design of an aerodynamic high lift device which provided a solution to an aircraft performance problem are described. The performance problem of converting a high speed cruise airfoil into a low speed aerodynamic shape that would provide landing and take-off characteristics superior to those available with contemporary high lift devices are addressed. The need for an improved wing leading edge device that would complement the high lift performance of a triple slotted trailing edge flap is examined. The mechanical and structural aspects of the variable camber flap are discussed and the aerodynamic performance aspects only as they relate to the invention and design of the device are presented.

  12. Flap Edge Aeroacoustic Measurements and Predictions

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F.; Humphreys, William M., Jr.

    2000-01-01

    An aeroacoustic model test has been conducted to investigate the mechanisms of sound generation on high-lift wing configurations. This paper presents an analysis of flap side-edge noise, which is often the most dominant source. A model of a main element wing section with a half-span flap was tested at low speeds of up to a Mach number of 0.17, corresponding to a wing chord Reynolds number of approximately 1.7 million. Results are presented for flat (or blunt), flanged, and round flap-edge geometries, with and without boundary-layer tripping, deployed at both moderate and high flap angles. The acoustic database is obtained from a Small Aperture Directional Array (SADA) of microphones, which was constructed to electronically steer to different regions of the model and to obtain farfield noise spectra and directivity from these regions. The basic flap-edge aerodynamics is established by static surface pressure data, as well as by Computational Fluid Dynamics (CFD) calculations and simplified edge flow analyses. Distributions of unsteady pressure sensors over the flap allow the noise source regions to be defined and quantified via cross-spectral diagnostics using the SADA output. It is found that shear layer instability and related pressure scatter is the primary noise mechanism. For the flat edge flap, two noise prediction methods based on unsteady-surface-pressure measurements are evaluated and compared to measured noise. One is a new causality spectral approach developed here. The other is a new application of an edge-noise scatter prediction method. The good comparisons for both approaches suggest that much of the physics is captured by the prediction models. Areas of disagreement appear to reveal when the assumed edge noise mechanism does not fully define, the noise production. For the different edge conditions, extensive spectra and directivity are presented. Significantly, for each edge configuration, the spectra for different flow speeds, flap angles, and

  13. Forehead flap in maxillofacial surgery: Our experiences

    PubMed Central

    Ahmed, Syed S.; Ghassemi, Alireza; Rehman, Sajjad A.; Ansari, Md. Kaleem

    2015-01-01

    The forehead flap is a commonly used technique to reconstruct the deep and large nasal defects. It can be conveniently performed under local or general anesthesia and provides a very good color and texture matching to the nasal skin, which makes it a suitable graft harvesting site for nasal reconstruction. It has only single disadvantage disadvantagethat it is a two-stage procedure and “finishing” surgeries are needed occasionally for best surgical and cosmetic outcome. In this paper, we describe three different applications of forehead flaps. PMID:26668457

  14. [Aseptic bone flap osteonecrosis following cranioplasty after decompressive cranietomy].

    PubMed

    Smoll, Nicolas R; Stienen, Martin N; Schaller, Karl; Gautschi, Oliver P

    2013-06-19

    This case report discusses a case of aseptic osteonecrosis in a cranioplasty bone flap after decompressive craniectomy, which is a known, but rare complication after autologous cranioplasty. We suggest that the pathophysiology of cranial bone flap necrosis may have a similar pathophysiology to free flap necrosis/failure. The key suggested problem causing the osteonecrosis is vessel thrombosis within the smaller vessels of the bone flap due to the prothrombotic effects of the factors released during drilling of the bone flap. Suspicious local findings like wound dehiscence or fluid leakage should lead to a head computed tomography in order to discuss a prophylactic artificial second cranioplasty if necessary. PMID:23773942

  15. Switch Flap for Upper Eyelid Reconstruction—How Soon Should the Flap Be Divided?

    PubMed Central

    Yanai, Tetsu; Yasuta, Masato; Kawano, Hiroshige; Ishihara, Yasuhiro; Kikuchi, Mamoru

    2016-01-01

    Background: The results of a cohort of patients treated at one institution for upper eyelid reconstruction with the switch flap method after a defect due to excision of malignant tumor were reviewed. Methods: A retrospective data file review of all patients who had undergone total upper eyelid reconstruction with the switch flap method was conducted at the Saga University Hospital between April 2000 and October 2014. The follow-up lasted for varying periods during which the preoperative and postoperative photographs were compared as well. Results: A total of 10 patients with upper eyelid tumors, that is, 7 sebaceous carcinoma, 2 squamous cell carcinoma, and 1 basal cell carcinoma, underwent reconstructive surgery. With the switch flap technique, the defects resulting from tumor excision were completely covered in all cases. The mean of defect widths after tumor excision (A) was 18.8 mm (range, 15–25 mm), the mean of widths of switch flaps (B) was 13.3 mm (range, 8–22 mm), and the mean of B/A ratios was 0.69 (range, 0.5–0.88). When the switch flap was divided at 7 to 14 days, there was no flap loss, trichiasis, or corneal ulcer. Conclusion: Our protocol managed to make flaps with a B/A ratio of 0.5–0.7, and the flaps were divided at 7 to 14 days after surgery, the timing of which was much earlier than in the conventional method, lessening the possibility of complications. PMID:27200257

  16. Tunnelled tensor fascia lata flap for complex abdominal wall reconstruction

    PubMed Central

    Wang, Frederick; Buonocore, Samuel; Narayan, Deepak

    2011-01-01

    This study describes the treatment of two patients with recurrent, infected abdominal wall defects using bilateral delayed and tunnelled pedicled tensor fascia lata (TFL) myofascial flaps. TFL flaps were elevated and delayed for 4 weeks in both cases. In the second case, Parietex Composite mesh was positioned underneath the TFL flap and allowed to incorporate. After a delay of 4 weeks, the flaps were harvested and tunnelled subcutaneously to repair the abdominal wall defect. Both patients have stable repairs but had donor site seromas requiring drainage. Cadaver dissection was also performed to identify structures related to TFL flap harvest. We identified a variant of lateral femoral cutaneous nerve that traversed the TFL flap, necessitating meticulous dissection during surgery. In summary, we describe a new technique of incorporating mesh into the TFL prior to flap harvest for reconstruction of complex abdominal wall. PMID:22707661

  17. Review of Skull Base Reconstruction Using Locoregional Flaps and Free Flaps in Children and Adolescents

    PubMed Central

    Yano, Tomoyuki; Tanaka, Kentarou; Kishimoto, Seiji; Iida, Hideo; Okazaki, Mutsumi

    2011-01-01

    Tumors of the skull base are rare in children, and reconstruction in such patients has rarely been reported. We reviewed 16 cases of skull base reconstruction in patients under 18 years. The study group consisted of 10 boys and 6 girls, whose ages ranged from 2 to 17 years. Of the 16 cases, eight tumors were benign and eight were malignant. Defects were anterior in six cases, lateral in eight cases, and anterolateral in two cases. Reconstruction was performed with locoregional flaps in 11 cases and with free flaps in 5 cases. No significant difference was found between locoregional flaps and free flaps in total operative time, intraoperative blood loss, or postoperative hospital stay. However, in some cases, total operative time, reconstruction time, and blood loss increased to a degree unacceptable for pediatrics. Minor complications occurred in three patients and a major complication occurred in one case. Of four patients, three patients with postoperative complications had undergone chemoradiotherapy. Because of the physical weakness of pediatric patients, complicated reconstructive procedure should be avoided. We believe locoregional flaps will become the first choice for reconstruction. However, if patients have large, complex defects and have received radiotherapy, appropriate free flaps should be used to avoid postoperative complications. PMID:22547961

  18. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight. PMID:27030773

  19. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight.

  20. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control... airplanes, it must be designed to account for the unsummetrical loads resulting from flight with the engines... independent of the flap drive system; or by an approved equivalent means; or (2) Be designed so that...

  1. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control... airplanes, it must be designed to account for the unsummetrical loads resulting from flight with the engines... independent of the flap drive system; or by an approved equivalent means; or (2) Be designed so that...

  2. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control... airplanes, it must be designed to account for the unsummetrical loads resulting from flight with the engines... independent of the flap drive system; or by an approved equivalent means; or (2) Be designed so that...

  3. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control... airplanes, it must be designed to account for the unsummetrical loads resulting from flight with the engines... independent of the flap drive system; or by an approved equivalent means; or (2) Be designed so that...

  4. Enhanced Correlation of SMART Active Flap Rotor Loads

    NASA Technical Reports Server (NTRS)

    Kottapalli, Sesi

    2011-01-01

    This is a follow-on study to a 2010 correlation effort. Measured data from the SMART rotor test in the NASA Ames 40- by 80- Foot Wind Tunnel are compared with CAMRAD II calculations. As background, during the wind tunnel test, unexpectedly high inboard loads were encountered, and it was hypothesized at that time that due to changes in the flexbeams over the years, the flexbeam properties used in the analysis needed updating. Boeing Mesa, recently updated these properties. This correlation study uses the updated flexbeam properties. Compared to earlier studies, the following two enhancements are implemented: i) the inboard loads (pitchcase and flexbeam loads) correlation is included for the first time (reliable prediction of the inboard loads is a prerequisite for any future anticipated flight-testing); ii) the number of blade modes is increased to better capture the flap dynamics and the pitchcase-flexbeam dynamics. Also, aerodynamically, both the rolled-up wake model and the more complex, multiple trailer wake model are used, with the latter slightly improving the blade chordwise moment correlation. This sensitivity to the wake model indicates that CFD is needed. Three high-speed experimental cases, one uncontrolled free flap case and two commanded flap cases, are considered. The two commanded flap cases include a 2o flap deflection at 5P case and a 0o flap deflection case. For the free flap case, selected modifications to the HH-06 section flap airfoil pitching moment table are implemented. For the commanded 2o flap case, the experimental flap variation is approximately matched by increasing the analytical flap hinge stiffness. This increased flap hinge stiffness is retained for the commanded 0o flap case also, which is treated as a free flap case, but with larger flap hinge stiffness. The change in the mid-span and outboard loads correlation due to the updating of the flexbeam properties is not significant. Increasing the number of blade modes results in an

  5. A Miniature Controllable Flapping Wing Robot

    NASA Astrophysics Data System (ADS)

    Arabagi, Veaceslav Gheorghe

    The agility and miniature size of nature's flapping wing fliers has long baffled researchers, inspiring biological studies, aerodynamic simulations, and attempts to engineer their robotic replicas. Flapping wing flight is characterized by complex reciprocating wing kinematics, transient aerodynamic effects, and very small body lengths. These characteristics render robotic flapping wing aerial vehicles ideal for surveillance and defense applications, search and rescue missions, and environment monitoring, where their ability to hover and high maneuverability is immensely beneficial. One of the many difficulties in creating flapping wing based miniature robotic aerial vehicles lies in generating a proper wing trajectory that would result in sufficient lift forces for hovering and maneuvering. Since design of a flapping wing system is a balance between overall weight and the number of actuated inputs, we take the approach of having minimal controlled inputs, allowing passive behavior wherever possible. Hence, we propose a completely passive wing pitch reversal design that relies on wing inertial dynamics, an elastic energy storage mechanism, and low Reynolds number aerodynamic effects. Theoretical models, compiling previous research on piezoelectric actuators, four-bar transmissions, and aerodynamics effects, are developed and used as basis for a complete numerical simulation. Limitations of the model are discussed in comparison to experimental results obtained from a working prototype of the proposed passive pitch reversal flapping wing mechanism. Given that the mechanism is under-actuated, methods to control lift force generation by actively varying system parameters are proposed, discussed, and tested experimentally. A dual wing aerial platform is developed based on the passive pitch reversal wing concept. Design considerations are presented, favoring controllability and structural rigidity of the final platform. Finite element analysis and experimental

  6. The innervated anterolateral thigh flap: anatomical study and clinical implications.

    PubMed

    Ribuffo, Diego; Cigna, Emanuele; Gargano, Francesco; Spalvieri, Cristina; Scuderi, Nicolò

    2005-02-01

    During the past 20 years, the neural anatomy of many flaps has been investigated, although no extensive studies have been reported yet on the anterolateral thigh flap. The goal of this study was to describe the sensory territories of the nerves supplying the anterolateral thigh flap with dissections on fresh cadavers and with local anesthetic injections in living subjects. The sensate anterolateral thigh flap is typically described as innervated by the lateral cutaneous femoral nerve. Two other well-known nerves, the superior perforator nerve and the median perforator nerve, which enter the flap at its medial border, might have a role in anterolateral thigh flap innervation. Twenty-nine anterolateral thigh flaps were elevated in 15 cadavers, and the lateral cutaneous femoral nerve, the superior perforator nerve, and median perforator nerve were dissected. In the injection study, the lateral cutaneous femoral nerve, superior perforator nerve, and median perforator nerve in 16 thighs of eight subjects were sequentially blocked. The resulting sensory deficit from each injection was mapped on the skin and superimposed on the marked anterolateral thigh flap territory. The study shows that the sensate anterolateral thigh flap is basically innervated by all three nerves. The lateral cutaneous femoral nerve was present in 29 of 29 thighs, whereas the superior perforator nerve was present in 25 of 29 and the median perforator nerve in 24 of 29 thighs. Furthermore, in the proximal half of the flap, the lateral cutaneous femoral nerve lies deep, whereas the superior perforator nerve and median perforator nerve lie more superficially. Whereas the lateral cutaneous femoral nerve innervates the entire flap, the superior perforator nerve innervates 25 percent of the flap and the median perforator nerve innervates 60 percent of the flap. Clinically, a small anterolateral thigh flap (7 x 5 cm) can be raised sparing the lateral cutaneous femoral nerve and using only the selective

  7. Reconstruction of pressure sores with perforator-based propeller flaps.

    PubMed

    Jakubietz, Rafael G; Jakubietz, Danni F; Zahn, Robert; Schmidt, Karsten; Meffert, Rainer H; Jakubietz, Michael G

    2011-03-01

    Perforator flaps have been successfully used for reconstruction of pressure sores. Although V-Y advancement flaps approximate debrided wound edges, perforator-based propeller flaps allow rotation of healthy tissue into the defect. Perforator-based propeller flaps were planned in 13 patients. Seven pressure sores were over the sacrum, five over the ischial tuberosity, and one on the tip of the scapula. Three patients were paraplegic, six were bedridden, and five were ambulatory. In three patients, no perforators were found. In 10 patients, propeller flaps were transferred. In two patients, total flap necrosis occurred, which was reconstructed with local advancement flaps. In two cases, a wound dehiscence occurred and had to be revised. One hematoma required evacuation. No further complications were noted. No recurrence at the flap site occurred. Local perforator flaps allow closure of pressure sores without harvesting muscle. The propeller version has the added benefit of transferring tissue from a distant site, avoiding reapproximation of original wound edges. Twisting of the pedicle may cause torsion and venous obstruction. This can be avoided by dissecting a pedicle of at least 3 cm. Propeller flaps are a safe option for soft tissue reconstruction of pressure sores.

  8. Aerodynamic flight performance in flap-gliding birds and bats.

    PubMed

    Muijres, Florian T; Henningsson, Per; Stuiver, Melanie; Hedenström, Anders

    2012-08-01

    Many birds use a flight mode called undulating or flap-gliding flight, where they alternate between flapping and gliding phases, while only a few bats make use of such a flight mode. Among birds, flap-gliding is commonly used by medium to large species, where it is regarded to have a lower energetic cost than continuously flapping flight. Here, we introduce a novel model for estimating the energetic flight economy of flap-gliding animals, by determining the lift-to-drag ratio for flap-gliding based on empirical lift-to-drag ratio estimates for continuous flapping flight and for continuous gliding flight, respectively. We apply the model to flight performance data of the common swift (Apus apus) and of the lesser long-nosed bat (Leptonycteris yerbabuenae). The common swift is a typical flap-glider while-to the best of our knowledge-the lesser long-nosed bat does not use flap-gliding. The results show that, according to the model, the flap-gliding common swift saves up to 15% energy compared to a continuous flapping swift, and that this is primarily due to the exceptionally high lift-to-drag ratio in gliding flight relative to that in flapping flight for common swifts. The lesser long-nosed bat, on the other hand, seems not to be able to reduce energetic costs by flap-gliding. The difference in relative costs of flap-gliding flight between the common swift and the lesser long-nosed bat can be explained by differences in morphology, flight style and wake dynamics. The model presented here proves to be a valuable tool for estimating energetic flight economy in flap-gliding animals. The results show that flap-gliding flight that is naturally used by common swifts is indeed the most economic one of the two flight modes, while this is not the case for the non-flap-gliding lesser long-nosed bat. PMID:22726811

  9. Power performance optimization and loads alleviation with active flaps using individual flap control

    NASA Astrophysics Data System (ADS)

    Pettas, Vasilis; Barlas, Thanasis; Gertz, Drew; Madsen, Helge A.

    2016-09-01

    The present article investigates the potential of Active Trailing Edge Flaps (ATEF) in terms of increase in annual energy production (AEP) as well as reduction of fatigue loads. The basis for this study is the DTU 10 MW Reference Wind Turbine (RWT) simulated using the aeroelastic code HAWC2. In an industrial-oriented manner the baseline rotor is upscaled by 5% and the ATEFs are implemented in the outer 30% of the blades. The flap system is kept simple and robust with a single flap section and control with wind speed, rotor azimuth, root bending moments and angle of attack in flap's mid-section being the sensor inputs. The AEP is increased due to the upscaling but also further due to the flap system while the fatigue loads in components of interest (blade, tower, nacelle and main bearing) are reduced close to the level of the original turbine. The aim of this study is to demonstrate a simple and applicable method that can be a technology enabler for rotor upscaling and lowering cost of energy.

  10. First web-space reconstruction by the anterolateral thigh flap.

    PubMed

    Adani, Roberto; Tarallo, Luigi; Marcoccio, Ignazio; Fregni, Umberto

    2006-04-01

    Four patients with severe contracture of the first web space were treated with an anterolateral thigh perforator flap. The flap size ranged from 10 to 13 cm in length and from 7 to 8 cm in width. The donor site was closed directly and thinning of the flap was performed in all cases. All flaps survived and there were no re-explorations. Web space opening was maintained over the follow-up period. There was an average postoperative increase of the angle of the first web space of 61 degrees. The thinned anterolateral thigh flap provides a pliable vascularized tissue for resurfacing the skin after release of severe contracture of the first web space and represents a reliable alternative to other flaps.

  11. Incidence of flap procedures in the management of burn patients.

    PubMed

    Lineaweaver, William C; Craft-Coffman, Beretta; Oswald, Tanya M

    2015-03-01

    Increased survival of burn patients presents opportunities for reconstructive strategies to improve outcomes in management of acute and secondary burn injuries. To assess one such strategy, namely flap reconstruction, we reviewed cases performed during the first 4.5 years of the JMS Burn and Reconstruction Center. We found that flap procedures accounted for 0.8% of acute cases (23 of 2723 procedures) and 33% of secondary cases (260 of 790 procedures). This initial finding shows that in this practice flap procedures are applied to a small number of acute problems while flap procedures comprise 33% of secondary procedures. Reconstructive flap surgery plays a measurable role in burn treatment at this center. Further study of outcomes and timing could lead to better understanding of optimal strategies for flap reconstruction in burns.

  12. Changes in quantitative norepinephrine levels in delayed pig flank flaps.

    PubMed

    Cutting, C; Bumsted, R; Bardach, J; Mooney, M; Johnson, S

    1982-04-01

    A quantitative norepinephrine assay was used to follow tissue norepinephrine concentrations serially in bipedicle delayed pig flank flaps. In contrast to a previous study by Palmer, norepinephrine concentration decreased significantly after 24 hr, but then gradually returned to normal at 10 days. This suggests that the pig flank flap maintains much of its adrenergic innervation following bipedicle delay. It appears unlikely that adrenergic denervation explains the delay phenomenon in this model. The combined results of this study and others suggest that the degree of adrenergic denervation of a flap is determined by the anatomic layout of the flap with respect to the underlying cutaneous adrenergic neural anatomy. This experiment suggests that the effectiveness of adrenergic blocking agents in improving flap survival is dependent on the degree of adrenergic denervation of the flap.

  13. Versatility of V-Y Flap in Gluteal Area

    PubMed Central

    El-Sabbagh, Ahmed

    2016-01-01

    BACKGROUND Lesions in perineal area are common. The usual treatment is coverage by skin graft and flaps which may be local, pedicled or free types. In this paper V-Y flaps were used to cover the defects. METHODS V-Y flaps were used in the gluteal area in 15 patients. Lesions were due to different causes. RESULTS Of 15 patients, 11 were males and 4 were females. Their ages ranged from 3 weeks to 52 years old. Two cases were due to myelomeningocele, necrotizing fasciitis (2 cases) and the rest were due to bed sores (11 cases). The flaps were located over the trochanter (3 cases), ischial (6 cases) and sacral (6 cases). Good healing and durable coverage were obtained in all cases except one case. CONCLUSION V-Y flap as a working horse flap is recommended in the gluteal area. PMID:27579271

  14. [Fundamentals and principles of grafts and flaps].

    PubMed

    Cruz-Navarro, Natalio; León-Dueñas, Eduardo

    2014-01-01

    Reconstructive surgery of large urethral stenosis and the management of congenital anomalies such as hypospadias and epispadias require covering large cutaneous and mucosal defects with different techniques. The objective of this work is to define the main differences between tissues to be transferred and to study the principles that must govern the management of the various flaps and grafts used for these techniques. We analyze the anatomical and physiological features that may be key to understand the success and possible failures of these procedures, and we review technical details that must accompany in every case, not only during the operation, but also during the preoperative and postoperative period. We conclude stating that grafts (mainly oral and preputial mucosa) and flaps are increasingly used for the repair of urethral stenosis. Grafts must be prepared adequately in the back table and thinned to the maximum, and also be fixed properly, to guarantee their immobility until neovascularization is assured.

  15. Forward speed effects on blown flap noise

    NASA Technical Reports Server (NTRS)

    Pennock, A. P.

    1977-01-01

    The effects of forward speed on the noise of under-the-wing (externally blown flaps, EBF) and over-the-wing (upper surface blown, USB) blown flap configurations were measured in wind tunnel model tests with cold jets. The results are presented without correction for the effects (e.g., signal convection, shear layer refraction) associated with flight simulation in a wind tunnel or free jet facility. Noise decreases were generally observed at microphones forward of the wing. The reductions were larger at the low frequencies (below peak SPL) than at the high (above peak SPL). Noise increases of 10 dB or more were observed at the aft microphones, especially in the high frequency range.

  16. Aerosound from corner flow and flap flow

    NASA Technical Reports Server (NTRS)

    Meecham, W. C.

    1982-01-01

    Noise generation at the edge of a wing flap is analyzed. The phenomenon as a single vortex moving around a corner in an incompressible, potential flow is modelled. Vortex image retarding effects are proposed as an explanation for small Strouhal numbers. The model surface pressures, sound pressures (using Curle's theory), and Mach number dependencies agree with wind tunnel experiments. A double pressure peak is found in the model (credited to image action) which is qualitatively similar to measured sound correlations. Incompressible flow aerosound calculations are discussed. The effects of a series of vortices moving in the same idealized potential flow are also studied. The vortices are assumed to be statistically independent so their intensities can be added. The frequency of appearance of the vortices are determined from measurements. Diffraction effects caused by the presence of the wing near the dipole sound radiators on the flap surfaces are included.

  17. [Pedicled versus free TRAM flap for breast reconstruction].

    PubMed

    Galla, T J; Lukas, B; Feller, A M

    1999-03-01

    In breast reconstruction, the free TRAM-flap offers many advantages over the pedicled TRAM-flap. Due to its superior perfusion, the free flap rarely develops necrosis. Shaping of the flap is easier due to the lack of the thick muscle pedicle. Because the rectus muscle is spared, there is minimal donor site morbidity. However, the necessary microvascular anastomoses reduced the acceptance of the free TRAM-flap. During a 13-months period, 51 breast reconstructions were performed in 41 patients, 31 unilateral and ten bilateral. 45 flaps served for delayed reconstruction and six flaps for immediate reconstruction. The operations were performed by two teams working simultaneously. The average operating time was 3.9 hours for unilateral and 6.9 hours for bilateral delayed reconstruction. For immediate reconstruction, 6.2 and 6.3 hours were required for uni- and bilateral procedures, respectively. In 38 flaps, the thoracodorsal vessels served as recipient vessels; 13 flaps were anastomosed to the internal mammary artery and vein. Postoperative complications were observed in 13 patients. Three vessel anastomoses had to be revised. In one flap, a partial necrosis occurred; in two flaps hematoma evacuation was necessary. Two patients suffered from fat necroses at the abdomen and one umbilicus was lost. Skin irritations and seromas at the abdomen occurred in five patients. Pulmonary embolism was diagnosed in one patient three weeks postoperatively. Abdominal hernias or bulging in the epigastric area were not observed up to 15 months after reconstruction. These results reveal a low complication rate for breast reconstruction with the free TRAM-flap. The advantages of this technique as compared to the pedicled technique are discussed.

  18. USB noise reduction by nozzle and flap modifications

    NASA Technical Reports Server (NTRS)

    Hayden, R. E.

    1976-01-01

    The development of concepts for reducing upper surface blown flap noise at the source through flap modifications and special nozzles is reviewed. In particular, recent results obtained on the aerodynamic and acoustic performance of flaps with porous surfaces near the trailing edge and multi-slotted nozzles are reviewed. Considerable reduction (6-10 db) of the characteristic low frequency peak is shown. The aerodynamic performance is compared with conventional systems, and prospects for future improvements are discussed.

  19. Flight test pilot evaluation of a delayed flap approach procedure

    NASA Technical Reports Server (NTRS)

    Bull, J. S.; Edwards, F. G.; Foster, J. D.; Hegarty, D. M.; Drinkwater, F. J., III

    1977-01-01

    Using NASA's CV-990 aircraft, a delayed flap approach procedure was demonstrated to nine guest pilots from the air transport industry. Four demonstration flights and 37 approaches were conducted under VFR weather conditions. A limited pilot evaluation of the delayed flap procedure was obtained from pilot comments and from questionaires they completed. Pilot acceptability, pilot workload, and ATC compatibility were quantitatively rated. The delayed flap procedure was shown to be feasible, and suggestions for further development work were obtained.

  20. Flapping instability of a liquid jet

    NASA Astrophysics Data System (ADS)

    Matas, Jean-Philippe; Cartellier, Alain

    2013-01-01

    We study the flapping instability observed when a liquid jet is incompletely atomized by a fast parallel gas stream: the remaining liquid jet is destabilized over a scale large compared with its radius, and breaks into liquid fragments. We characterize the symmetry of this instability and its frequency. The intact liquid length is measured as a function of gas and liquid velocity, and turns out to be longer than the one predicted by Raynal (1997) for a planar mixing layer. The frequency of the instability is measured with a spectral method, and is in agreement with the frequency observed for the planar shear instability, though slightly smaller. The planar, and not helical, symmetry of the instability makes it akin to a flapping instability, observed when a planar liquid sheet is atomized by two planar gas streams. We next measure drop sizes when the flapping instability is present, with a method based on image processing. Measured size distributions are in agreement with distributions observed in a mixing layer geometry for low gas velocities (long tail distribution). The mean drop diameter depends weakly on liquid velocity, and decreases as d10˜Ug0.9. On the contrary, Sauter diameter depends strongly on liquid velocity.

  1. Evaluation of flexible flapping wing concept

    NASA Astrophysics Data System (ADS)

    Rakotomamonjy, Thomas; Le Moing, Thierry; Danet, Brieuc; Gadoullet, Xavier; Osmont, Daniel; Dupont, Marc

    2009-03-01

    ONERA - The French Aerospace Lab - has launched an internal program on biologically-inspired Micro Air Vehicles (MAVs), covering many research topics such as unsteady aerodynamics, actuation, structural dynamics or control. The aim is to better understand the flapping flight performed in nature by insects, and to control state of the art technologies and applications in this field. For that purpose, a flight-dynamics oriented simulation model of a flapping-wing concept has been developed. This model, called OSCAB, features a body and two wings along which the aerodynamics efforts are integrated, so as to determine the global motion of the MAV. The model has been improved by taking into account the flexibility of the wings (flexion of the leading edge and passive torsion of the wings, induced by the flapping motion itself under wing inertia). Thus, it becomes possible to estimate the coupling between flexibility and the aerodynamic forces. Furthermore, the model shows that using elastic properties of the wings allows a diminution of the mechanical energy needed for wings motion, and a reduction of the number of actuators to be implanted into the MAV.

  2. Flapping inertia for selected rotor blades

    NASA Technical Reports Server (NTRS)

    Berry, John D.; May, Matthew J.

    1991-01-01

    Aerodynamics of helicopter rotor systems cannot be investigated without consideration for the dynamics of the rotor. One of the principal properties of the rotor which affects the rotor dynamics is the inertia of the rotor blade about its root attachment. Previous aerodynamic investigation have been performed on rotor blades with a variety of planforms to determine the performance differences due to blade planform. The blades tested for this investigation have been tested on the U.S. Army 2 meter rotor test system (2MRTS) in the NASA Langley 14 by 22 foot subsonic tunnel for hover performance. This investigation was intended to provide fundamental information on the flapping inertia of five rotor blades with differing planforms. The inertia of the bare cuff and the cuff with a blade extension were also measured for comparison with the inertia of the blades. Inertia was determined using a swing testing technique, using the period of oscillation to determine the effective flapping inertia. The effect of damping in the swing test was measured and described. A comparison of the flapping inertials for rectangular and tapered planform blades of approximately the same mass showed the tapered blades to have a lower inertia, as expected.

  3. Managing Flap Vortices via Separation Control

    NASA Technical Reports Server (NTRS)

    Greenblatt, David

    2006-01-01

    A pilot study was conducted on a flapped semi-span model to investigate the concept and viability of near-wake vortex management by means of boundary layer separation control. Passive control was achieved using a simple fairing and active control was achieved via zero mass-flux blowing slots. Vortex sheet strength, estimated by integrating surface pressures, was used to predict vortex characteristics based on inviscid rollup relations and vortices trailing the flaps were mapped using a seven-hole probe. Separation control was found to have a marked effect on vortex location, strength, tangential velocity, axial velocity and size over a wide range of angles of attack and control conditions. In general, the vortex trends were well predicted by the inviscid rollup relations. Manipulation of the separated flow near the flap edges exerted significant control over either outboard or inboard edge vortices while producing small lift and moment excursions. Unsteady surface pressures indicated that dynamic separation and attachment control can be exploited to perturb vortices at wavelengths shorter than a typical wingspan. In summary, separation control has the potential for application to time-independent or time-dependent wake alleviation schemes, where the latter can be deployed to minimize adverse effects on ride-quality and dynamic structural loading.

  4. Aerodynamics of high frequency flapping wings

    NASA Astrophysics Data System (ADS)

    Hu, Zheng; Roll, Jesse; Cheng, Bo; Deng, Xinyan

    2010-11-01

    We investigated the aerodynamic performance of high frequency flapping wings using a 2.5 gram robotic insect mechanism developed in our lab. The mechanism flaps up to 65Hz with a pair of man-made wing mounted with 10cm wingtip-to-wingtip span. The mean aerodynamic lift force was measured by a lever platform, and the flow velocity and vorticity were measured using a stereo DPIV system in the frontal, parasagittal, and horizontal planes. Both near field (leading edge vortex) and far field flow (induced flow) were measured with instantaneous and phase-averaged results. Systematic experiments were performed on the man-made wings, cicada and hawk moth wings due to their similar size, frequency and Reynolds number. For insect wings, we used both dry and freshly-cut wings. The aerodynamic force increase with flapping frequency and the man-made wing generates more than 4 grams of lift at 35Hz with 3 volt input. Here we present the experimental results and the major differences in their aerodynamic performances.

  5. Vortex leading edge flap assembly for supersonic airplanes

    NASA Technical Reports Server (NTRS)

    Rudolph, Peter K. C. (Inventor)

    1997-01-01

    A leading edge flap (16) for supersonic transport airplanes is disclosed. In its stowed position, the leading edge flap forms the lower surface of the wing leading edge up to the horizontal center of the leading edge radius. For low speed operation, the vortex leading edge flap moves forward and rotates down. The upward curve of the flap leading edge triggers flow separation on the flap and rotational flow on the upper surface of the flap (vortex). The rounded shape of the upper fixed leading edge provides the conditions for a controlled reattachment of the flow on the upper wing surface and therefore a stable vortex. The vortex generates lift and a nose-up pitching moment. This improves maximum lift at low speed, reduces attitude for a given lift coefficient and improves lift to drag ratio. The mechanism (27) to move the vortex flap consists of two spanwise supports (24) with two diverging straight tracks (64 and 68) each and a screw drive mechanism (62) in the center of the flap panel (29). The flap motion is essentially normal to the airloads and therefore requires only low actuation forces.

  6. Rotational flaps in oncologic breast surgery. Anatomical and technical considerations.

    PubMed

    Acea Nebril, Benigno; Builes Ramírez, Sergio; García Novoa, Alejandra; Varela Lamas, Cristina

    2016-01-01

    Local flaps are a group of surgical procedures that can solve the thoracic closure of large defects after breast cancer surgery with low morbidity. Its use in skin necrosis complications after conservative surgery or skin sparing mastectomies facilitates the initiation of adjuvant treatments and reduces delays in this patient group. This article describes the anatomical basis for the planning of thoracic and abdominal local flaps. Also, the application of these local flaps for closing large defects in the chest and selective flaps for skin coverage by necrosis in breast conserving surgery.

  7. Rotational flaps in oncologic breast surgery. Anatomical and technical considerations.

    PubMed

    Acea Nebril, Benigno; Builes Ramírez, Sergio; García Novoa, Alejandra; Varela Lamas, Cristina

    2016-01-01

    Local flaps are a group of surgical procedures that can solve the thoracic closure of large defects after breast cancer surgery with low morbidity. Its use in skin necrosis complications after conservative surgery or skin sparing mastectomies facilitates the initiation of adjuvant treatments and reduces delays in this patient group. This article describes the anatomical basis for the planning of thoracic and abdominal local flaps. Also, the application of these local flaps for closing large defects in the chest and selective flaps for skin coverage by necrosis in breast conserving surgery. PMID:27140865

  8. Monocortical Deep Circumflex Iliac Artery Flap in Jaw Reconstruction.

    PubMed

    Moon, Seong-Yong

    2015-06-01

    Conventionally deep circumflex iliac artery (DCIA) flap had been harvested as bicortical form. However, several complications and adverse effects occurred such as abnormal hip contour, hernia, severe bleeding tendency, gait disturbance, and hypoesthesia. All the 9 patients required reconstruction of the jaw with microvascular free flaps after radical resection. Monocortical bone segment was harvested from the anterior iliac crest, and the amount of bone harvested was from 47 to 90 mm (mean, 63 ± 14.6). Monocortical deep circumflex iliac artery flap has sufficient advantages in donor-site morbidity, which is one of the factors to choose flap.

  9. A novel animal model for skin flap prelamination with biomaterials

    PubMed Central

    Zhou, Xianyu; Luo, Xusong; Liu, Fei; Gu, Chuan; Wang, Xi; Yang, Qun; Qian, Yunliang; Yang, Jun

    2016-01-01

    Several animal models of skin flap construction were reported using biomaterials in a way similar to prefabrication. However, there are few animal model using biomaterials similar to prelamination, another main way of clinical skin flap construction that has been proved to be reliable. Can biomaterials be added in skin flap prelamination to reduce the use of autogenous tissues? Beside individual clinical attempts, animal model is needed for randomized controlled trial to objectively evaluate the feasibility and further investigation. Combining human Acellular Dermal Matrix (hADM) and autologous skin graft, we prelaminated flaps based on inguinal fascia. One, two, three and four weeks later, hADM exhibited a sound revascularization and host cell infiltration. Prelaminated skin flaps were then raised and microsurgically transplanted back to groin region. Except for flaps after one week of prelamination, flaps from other subgroups successfully reconstructed defects. After six to sixteen weeks of transplantation, hADM was proved to being able to maintain its original structure, having a wealth of host tissue cells and achieving full revascularization.To our knowledge, this is the first animal model of prelaminating skin flap with biomaterials. Success of this animal model indicates that novel flap prelamination with biomaterials is feasible. PMID:27659066

  10. Numerical analysis of the V-Y shaped advancement flap.

    PubMed

    Remache, D; Chambert, J; Pauchot, J; Jacquet, E

    2015-10-01

    The V-Y advancement flap is a usual technique for the closure of skin defects. A triangular flap is incised adjacent to a skin defect of rectangular shape. As the flap is advanced to close the initial defect, two smaller defects in the shape of a parallelogram are formed with respect to a reflection symmetry. The height of the defects depends on the apex angle of the flap and the closure efforts are related to the defects height. Andrades et al. 2005 have performed a geometrical analysis of the V-Y flap technique in order to reach a compromise between the flap size and the defects width. However, the geometrical approach does not consider the mechanical properties of the skin. The present analysis based on the finite element method is proposed as a complement to the geometrical one. This analysis aims to highlight the major role of the skin elasticity for a full analysis of the V-Y advancement flap. Furthermore, the study of this technique shows that closing at the flap apex seems mechanically the most interesting step. Thus different strategies of defect closure at the flap apex stemming from surgeon's know-how have been tested by numerical simulations. PMID:26342442

  11. Lower extremity reconstruction with the anterolateral thigh flap.

    PubMed

    Nosrati, Naveed; Chao, Albert H; Chang, David W; Yu, Peirong

    2012-05-01

    The versatility and location of the anterolateral thigh (ALT) flap make it well suited for lower extremity reconstruction. The purpose of this study was to evaluate surgical and functional outcomes by specific anatomic regions in the lower extremity to better define the role of the ALT flap in lower extremity reconstruction. A retrospective review of patients undergoing lower extremity reconstruction with an ALT flap between July 2002 and December 2010 was performed. Total 46 patients underwent lower extremity reconstruction with an ALT flap, of whom 29 (63%) had a pedicled flap and 17 (37%) a microvascular free flap. Defects were located in the hip/buttocks (n = 8), groin (n = 13), thigh (n = 8), knee (n = 5), leg (n = 6), and foot/ankle (n = 6). The mean postoperative follow-up was 4 months. Total flap loss occurred in two patients (4%). There were 11 recipient site complications (24%). The most common complication was recipient site seroma, which occurred in five patients (11%), all of whom had hip/buttock or groin defects. Overall, 38 patients (83%) returned to their preoperative functional status. The ALT flap is an effective method of lower extremity reconstruction. It can be performed as a pedicled or free flap, with good surgical and functional outcomes. PMID:22399252

  12. Clinical Experiences with the Scapular Fascial Free Flap

    PubMed Central

    Park, Il Ho; Chang, Yong Joon; Kim, Jae Hyun

    2016-01-01

    Background The goal of reconstruction is to provide coverage of exposed vital structures with well-vascularized tissue for optimal restoration of form and function. Here, we present our clinical experience with the use of the scapular fascial free flap to correct facial asymmetry and to reconstruct soft tissue defects of the extremities. Methods We used a scapular fascial free flap in 12 cases for soft tissue coverage of the extremities or facial soft tissue augmentation. Results The flaps ranged in size from 3×12 to 13×23 cm. No cases of total loss of the flap occurred. Partial loss of the flap occurred in 1 patient, who was treated with a turnover flap using the adjacent scapular fascial flap and a skin graft. Partial loss of the skin graft occurred in 4 patients due to infection or hematoma beneath the graft, and these patients underwent another skin graft. Four cases of seroma at the donor site occurred, and these cases were treated with conservative management or capsulectomy and quilting sutures. Conclusions The scapular fascial free flap has many advantages, including a durable surface for restoration of form and contours, a large size with a constant pedicle, adequate surface for tendon gliding, and minimal donor-site scarring. We conclude that despite the occurrence of a small number of complications, the scapular fascial free flap should be considered to be a viable option for soft tissue coverage of the extremities and facial soft tissue augmentation. PMID:27689051

  13. Clinical Experiences with the Scapular Fascial Free Flap

    PubMed Central

    Park, Il Ho; Chang, Yong Joon; Kim, Jae Hyun

    2016-01-01

    Background The goal of reconstruction is to provide coverage of exposed vital structures with well-vascularized tissue for optimal restoration of form and function. Here, we present our clinical experience with the use of the scapular fascial free flap to correct facial asymmetry and to reconstruct soft tissue defects of the extremities. Methods We used a scapular fascial free flap in 12 cases for soft tissue coverage of the extremities or facial soft tissue augmentation. Results The flaps ranged in size from 3×12 to 13×23 cm. No cases of total loss of the flap occurred. Partial loss of the flap occurred in 1 patient, who was treated with a turnover flap using the adjacent scapular fascial flap and a skin graft. Partial loss of the skin graft occurred in 4 patients due to infection or hematoma beneath the graft, and these patients underwent another skin graft. Four cases of seroma at the donor site occurred, and these cases were treated with conservative management or capsulectomy and quilting sutures. Conclusions The scapular fascial free flap has many advantages, including a durable surface for restoration of form and contours, a large size with a constant pedicle, adequate surface for tendon gliding, and minimal donor-site scarring. We conclude that despite the occurrence of a small number of complications, the scapular fascial free flap should be considered to be a viable option for soft tissue coverage of the extremities and facial soft tissue augmentation.

  14. Monitoring flap for buried free tissue transfer: its importance and reliability.

    PubMed

    Cho, Byung Chae; Shin, Dong Pill; Byun, Jin Suk; Park, Jae Woo; Baik, Bong Soo

    2002-10-01

    To improve the success rate of microsurgical flap transfers into a buried area, it is important to monitor the circulation of the flap during the early stage. A monitoring flap includes such advantages as simplicity, reliability, noninvasiveness, and the ability to continuously monitor the vascular status of various buried flaps. This article describes experiences related to the importance and reliability of a monitoring flap. A total of 109 flaps in 99 patients were treated with buried free flaps, including a monitoring flap, between 1990 and 1999. Forty-nine patients received a tubed free radial forearm flap with a skin-monitoring flap, and six received a free jejunal flap with a jejunal segment monitoring flap for the reconstruction of the esophagus. Vascularized fibular grafts with a skin monitoring flap or peroneus longus muscle monitoring flap were used for reconstructing the mandible in six patients and for treating osteonecrosis of the femoral head in 48 flaps in 38 patients. Monitoring flap abnormalities were indicated in 14 flaps; therefore, immediate revisions were performed on the pedicle of the monitoring flap and microanastomosis site. Among these 14 flaps, nine showed true thrombosis and five showed false-positive thrombosis. Among the nine flaps that showed true thrombosis, five were salvaged and four were finally lost. The false-positive thrombosis in the five flaps was attributed to torsion or tension of the perforator of the monitoring flap in three flaps, an unclear determination in one flap because the monitoring flap size was too small, and damage to the perforator in the last flap. The total thrombosis rate was 8.3 percent (nine of 109), and the failure rate of the free tissue transfer was 3.7 percent (four of 109). The overall sensitivity of the monitoring flap was 100 percent, the predictive value of a positive test was 64 percent (nine of 14), and false-positive results occurred in 36 percent (five of 14). The salvage rate was 55.6 percent

  15. The radix nasi island flap: a versatile musculocutaneous flap for defects of the eyelids, nose, and malar region.

    PubMed

    Seyhan, Tamer

    2009-03-01

    A versatile musculocutan flap from the radix nasi region, the radix nasi island flap, is described. The flap has an axial blood supply derived from the dorsal nasal branch of the ophthalmic artery which is anastomosed to the terminal branch of the facial artery. The flap includes the skin, subcutaneous tissue, and procerus muscle. Ten patients, aged 50 to 86 years, have been reconstructed with this flap for defects in the nose (in 4 cases), midface (in 4 cases) and lower eyelids (in 2 cases). The mean flap size was 17 x 23 mm (range: 15 x 20 to 20 x 27 mm). All flaps fully survived. Additional complications and morbidity were not observed. The donor sites were closed a primarily closure in all cases. Follow-up ranged from 3 to 12 months (mean: 8.2 months). The radix nasi flap is a safe flap, has minimal donor site morbidity, and is especially suited for nasal and midface reconstruction in terms of attaining a suitable color and thickness. PMID:19305249

  16. Navier-Stokes Computations of a Wing-Flap Model With Blowing Normal to the Flap Surface

    NASA Technical Reports Server (NTRS)

    Boyd, D. Douglas, Jr.

    2005-01-01

    A computational study of a generic wing with a half span flap shows the mean flow effects of several blown flap configurations. The effort compares and contrasts the thin-layer, Reynolds averaged, Navier-Stokes solutions of a baseline wing-flap configuration with configurations that have blowing normal to the flap surface through small slits near the flap side edge. Vorticity contours reveal a dual vortex structure at the flap side edge for all cases. The dual vortex merges into a single vortex at approximately the mid-flap chord location. Upper surface blowing reduces the strength of the merged vortex and moves the vortex away from the upper edge. Lower surface blowing thickens the lower shear layer and weakens the merged vortex, but not as much as upper surface blowing. Side surface blowing forces the lower surface vortex farther outboard of the flap edge by effectively increasing the aerodynamic span of the flap. It is seen that there is no global aerodynamic penalty or benefit from the particular blowing configurations examined.

  17. [Elimination of isolated gingival atrophy by laterally positioned flap and free mucogingival autografts in combination with coronally positioned flap].

    PubMed

    Kovaćević, K; Leković, V

    1991-01-01

    Mucogingival surgical procedures such as laterally (horizontally) positioned flap, double papillae positioned flap and free mucogingival autografts have been recommended for the prevention and treatment of isolated gingival atrophy. These procedures can bi performed either independently or in combination with coronally positioned flap. In our study, for covering of exposed tooth roots, we applied laterally positioned flap and free mucogingival autografts in combination with coronally positioned flap. The obtained therapeutic results showed that six months after the surgery the exposure of tooth necks in patients treated by laterally positioned flap, decreased by 2.54 mm. Somewhat better results were obtained in the group of patients treated by fre mucogingival autografts in combination with coronally positioned flap. Within the same time interval, the total surface area of exposed tooth roots decreased by 59.76% in the group of patients treated by laterally positioned flap, i.e. by 62.25% in the group of patients treated by free mucogingival autografts in combination with coronally positioned flap. PMID:1785128

  18. Propeller Flap for Complex Distal Leg Reconstruction: A Versatile Alternative when Reverse Sural Artery Flap is Not Feasible.

    PubMed

    Ademola, Samuel A; Michael, Afieharo I; Oladeji, Femi J; Mbaya, Kefas M; Oyewole, O

    2015-01-01

    Reverse sural artery fasciocutaneous flap has become a workhorse for the reconstruction of distal leg soft tissue defects. When its use is not feasible, perforator-based propeller flap offers a better, easier, faster, and cheaper alternative to free flap. We present our experience with two men both aged 34 years who sustained Gustilo 3B injuries from gunshot. The donor area for reversed sural artery flap was involved in the injuries. They had early debridement, external fixation, and wound coverage with perforator-based propeller flaps. The donor sites were covered with skin graft. All flaps survived. There were minor wound edge ulcers due to the pressure of positioning that did not affect flap survival and the ulcers healed with conservative management. Perforator-based propeller flap is a versatile armamentarium for reconstruction of soft tissue defects of the distal leg in resource-constrained settings, especially when the donor area for a reverse flow sural flap artery is involved in the injury.

  19. [Fasciocutaneous forearm flaps in the management of the catastrophic hand].

    PubMed

    Herrera-Tenorio, J G; Gómez-Cansino, E

    2014-01-01

    This paper describes a series of cases with severe hand injury that required antebrachial flaps as part of treatment, and their functional results. The clinical records of patients with a diagnosis of traumatic hand injury and major skin cover losses, reconstructed with a reverse-flow forearm flap, were reviewed. The following variables were studied: type of flap, sex, age, mechanism of injury, receiver site, size, adjacent injuries and their treatment, vascular integrity test prior to flap placement, operative time, follow-up and complications. A total of 25 patients were included, with 25 reverse-flow fasciocutaneous forearm flaps; in 15 of them the blood supply was based on the radial artery and in 10 in the posterior interosseous artery. The Allen test was used in 13 cases of radial flaps (RF) to check the integrity of the superficial palmar arch; Doppler ultrasound was used in the remaining two cases. Sixteen cases (64%) underwent bone and tendon reconstruction, four cases (16%) isolated tenorrhaphy of one or several tendons, two cases (8%) isolated osteosynthesis, one case due to electrical burn underwent Littler opponensplasty with a radial flap in the anterior aspect of the wrist (4%), and in two cases (8%) an isolated flap was used. In one 67 year-old patient (4%) there was congestion and total loss of the posterior interosseous flap. The recommended indications for this type of flap are: coverage of the distal forearm, hand dorsum and fingers, first interdigital space, palmar region of the wrist and hand. Only two cases required coverage of the palmar region of the wrist and hand, and they were both treated with radial flaps, probably for reasons of anatomical convenience. PMID:26016286

  20. Intraoperative Flap Complications in LASIK Surgery Performed by Ophthalmology Residents

    PubMed Central

    Romero-Diaz-de-Leon, Lorena; Serna-Ojeda, Juan Carlos; Navas, Alejandro; Graue-Hernández, Enrique O.; Ramirez-Miranda, Arturo

    2016-01-01

    Purpose: To report the rate of flap-related complications in LASIK surgery performed by in-training ophthalmology residents and to analyze the risk factors for these complications. Methods: We analyzed 273 flap dissections in 145 patients from March 2013 to February 2014. We included all LASIK surgeries performed by 32 ophthalmology residents using a Moria M2 microkeratome. All the flap-related complications were noted. Comparison between both groups with and without complications was performed with an independent Student's t-test and relative risks were calculated. Results: There were 19 flap-related complications out of the 273 flap dissections (6.95%). The most common complication was incomplete flap dissection (n = 10; 3.66%), followed by free-cap (n = 5; 1.83%), and flap-buttonhole (n = 2; 0.73%). There was no significant difference between the complicated and uncomplicated cases in terms of the right versus the left eye, pachymetry results, white-to-white diameter, and spherical equivalent. But this difference was significant for mean keratometry (P = 0.008), K-min (P = 0.01), and K-max (P = 0.03) between these groups. Final visual acuity after rescheduling laser treatment was similar in both groups. Relative risks for flap-related complications were 2.03 for the first LASIK surgery (CI 95% 0.64 to 6.48; P = 0.22) and 1.26 (CI 95% 0.43 to 3.69; P = 0.66) for the surgeon's flap-related complications. Female gender presented an odds ratio of 2.48 (CI 95% 0.68 to 9.00; P = 0.16) for complications. Conclusion: Flap-related complications are common intraoperative event during LASIK surgery performed by in-training ophthalmologists. Keratometries and surgeon's first procedure represent a higher probability for flap related complications than some other biometric parameters of patient's eye. PMID:27621782

  1. Folding in and out: passive morphing in flapping wings.

    PubMed

    Stowers, Amanda K; Lentink, David

    2015-04-01

    We present a new mechanism for passive wing morphing of flapping wings inspired by bat and bird wing morphology. The mechanism consists of an unactuated hand wing connected to the arm wing with a wrist joint. Flapping motion generates centrifugal accelerations in the hand wing, forcing it to unfold passively. Using a robotic model in hover, we made kinematic measurements of unfolding kinematics as functions of the non-dimensional wingspan fold ratio (2-2.5) and flapping frequency (5-17 Hz) using stereo high-speed cameras. We find that the wings unfold passively within one to two flaps and remain unfolded with only small amplitude oscillations. To better understand the passive dynamics, we constructed a computer model of the unfolding process based on rigid body dynamics, contact models, and aerodynamic correlations. This model predicts the measured passive unfolding within about one flap and shows that unfolding is driven by centrifugal acceleration induced by flapping. The simulations also predict that relative unfolding time only weakly depends on flapping frequency and can be reduced to less than half a wingbeat by increasing flapping amplitude. Subsequent dimensional analysis shows that the time required to unfold passively is of the same order of magnitude as the flapping period. This suggests that centrifugal acceleration can drive passive unfolding within approximately one wingbeat in small and large wings. Finally, we show experimentally that passive unfolding wings can withstand impact with a branch, by first folding and then unfolding passively. This mechanism enables flapping robots to squeeze through clutter without sophisticated control. Passive unfolding also provides a new avenue in morphing wing design that makes future flapping morphing wings possibly more energy efficient and light-weight. Simultaneously these results point to possible inertia driven, and therefore metabolically efficient, control strategies in bats and birds to morph or recover

  2. Intraoperative Flap Complications in LASIK Surgery Performed by Ophthalmology Residents

    PubMed Central

    Romero-Diaz-de-Leon, Lorena; Serna-Ojeda, Juan Carlos; Navas, Alejandro; Graue-Hernández, Enrique O.; Ramirez-Miranda, Arturo

    2016-01-01

    Purpose: To report the rate of flap-related complications in LASIK surgery performed by in-training ophthalmology residents and to analyze the risk factors for these complications. Methods: We analyzed 273 flap dissections in 145 patients from March 2013 to February 2014. We included all LASIK surgeries performed by 32 ophthalmology residents using a Moria M2 microkeratome. All the flap-related complications were noted. Comparison between both groups with and without complications was performed with an independent Student's t-test and relative risks were calculated. Results: There were 19 flap-related complications out of the 273 flap dissections (6.95%). The most common complication was incomplete flap dissection (n = 10; 3.66%), followed by free-cap (n = 5; 1.83%), and flap-buttonhole (n = 2; 0.73%). There was no significant difference between the complicated and uncomplicated cases in terms of the right versus the left eye, pachymetry results, white-to-white diameter, and spherical equivalent. But this difference was significant for mean keratometry (P = 0.008), K-min (P = 0.01), and K-max (P = 0.03) between these groups. Final visual acuity after rescheduling laser treatment was similar in both groups. Relative risks for flap-related complications were 2.03 for the first LASIK surgery (CI 95% 0.64 to 6.48; P = 0.22) and 1.26 (CI 95% 0.43 to 3.69; P = 0.66) for the surgeon's flap-related complications. Female gender presented an odds ratio of 2.48 (CI 95% 0.68 to 9.00; P = 0.16) for complications. Conclusion: Flap-related complications are common intraoperative event during LASIK surgery performed by in-training ophthalmologists. Keratometries and surgeon's first procedure represent a higher probability for flap related complications than some other biometric parameters of patient's eye.

  3. Complications of surgery for radiotherapy skin damage

    SciTech Connect

    Rudolph, R.

    1982-08-01

    Complications of modern surgery for radiotherapy skin damage reviewed in 28 patients who had 42 operations. Thin split-thickness skin grafts for ulcer treatment had a 100 percent complication rate, defined as the need for further surgery. Local flaps, whether delayed or not, also had a high rate of complications. Myocutaneous flaps for ulcers had a 43 percent complication rate, with viable flaps lifting off radiated wound beds. Only myocutaneous flaps for breast reconstruction and omental flaps with skin grafts and Marlex mesh had no complications. The deeper tissue penetration of modern radiotherapy techniques may make skin grafts and flaps less useful. In reconstruction of radiation ulcers, omental flaps and myocutaneous flaps are especially useful, particularly if the radiation damage can be fully excised. The pull of gravity appears detrimental to myocutaneous flap healing and, if possible, should be avoided by flap design.

  4. The gust-mitigating potential of flapping wings.

    PubMed

    Fisher, Alex; Ravi, Sridhar; Watkins, Simon; Watmuff, Jon; Wang, Chun; Liu, Hao; Petersen, Phred

    2016-01-01

    Nature's flapping-wing flyers are adept at negotiating highly turbulent flows across a wide range of scales. This is in part due to their ability to quickly detect and counterract disturbances to their flight path, but may also be assisted by an inherent aerodynamic property of flapping wings. In this study, we subject a mechanical flapping wing to replicated atmospheric turbulence across a range of flapping frequencies and turbulence intensities. By means of flow visualization and surface pressure measurements, we determine the salient effects of large-scale freestream turbulence on the flow field, and on the phase-average and fluctuating components of pressure and lift. It is shown that at lower flapping frequencies, turbulence dominates the instantaneous flow field, and the random fluctuating component of lift contributes significantly to the total lift. At higher flapping frequencies, kinematic forcing begins to dominate and the flow field becomes more consistent from cycle to cycle. Turbulence still modulates the flapping-induced flow field, as evidenced in particular by a variation in the timing and extent of leading edge vortex formation during the early downstroke. The random fluctuating component of lift contributes less to the total lift at these frequencies, providing evidence that flapping wings do indeed provide some inherent gust mitigation.

  5. The gust-mitigating potential of flapping wings.

    PubMed

    Fisher, Alex; Ravi, Sridhar; Watkins, Simon; Watmuff, Jon; Wang, Chun; Liu, Hao; Petersen, Phred

    2016-01-01

    Nature's flapping-wing flyers are adept at negotiating highly turbulent flows across a wide range of scales. This is in part due to their ability to quickly detect and counterract disturbances to their flight path, but may also be assisted by an inherent aerodynamic property of flapping wings. In this study, we subject a mechanical flapping wing to replicated atmospheric turbulence across a range of flapping frequencies and turbulence intensities. By means of flow visualization and surface pressure measurements, we determine the salient effects of large-scale freestream turbulence on the flow field, and on the phase-average and fluctuating components of pressure and lift. It is shown that at lower flapping frequencies, turbulence dominates the instantaneous flow field, and the random fluctuating component of lift contributes significantly to the total lift. At higher flapping frequencies, kinematic forcing begins to dominate and the flow field becomes more consistent from cycle to cycle. Turbulence still modulates the flapping-induced flow field, as evidenced in particular by a variation in the timing and extent of leading edge vortex formation during the early downstroke. The random fluctuating component of lift contributes less to the total lift at these frequencies, providing evidence that flapping wings do indeed provide some inherent gust mitigation. PMID:27481211

  6. Breast ptosis managed by mastopexy using the triple flaps procedure.

    PubMed

    Gheita, Alaa; Moftah, Ali

    2011-02-01

    Breast ptosis is a highly unattractive appearance of the breast. In the mind, it is associated with aging, multiple pregnancies, lactation, and senile changes. Its correction by mastopexy presents one of the greatest challenges to the breast surgeon aiming at a pleasant full conical shape and stability of the results. The authors present their mastopexy procedure using a triple-flap method based on the principle of a superior pedicle flap mammaplasty. The technique, presented in detail, basically consists of a superior pedicle dermaglandular flap that carries the nipple-areola complex between outer and inner flaps. The outer flap is rotated inward and upward behind the main superior pedicle to give fullness to the breast and fixed to the chest wall. The inner flap is double-breasted on top or superficial to outer flap, and both are sutured to each other resembling a hammock or a cradle that carries the main superior pedicle middle flap. The results are presented and advantages discussed. This method, besides its simplicity, gives good projection with a pleasant and attractive conical shape to the breast and upper fullness, frequently negating the need for an implant. In addition, the results were stable in the long term, with no need for a mesh or any other foreign material.

  7. External Dacryocystorhinostomy with and Without Suturing the Posterior Mucosal Flaps

    PubMed Central

    Kaçaniku, Gazmend; Begolli, Ilir

    2014-01-01

    ABSTRACT Purpose: To evaluate the outcome of the external dacryocystorhinostomy with and without suturing the posterior mucosal flaps. Methods: This study included 106 patients with lacrimal drainage system disorders who underwent the external dacryocystorhinostomy. Fifty four patients (Group A) underwent external dacryocystorhinostomy with suturing anterior and posterior flaps of the lacrimal sac and nasal mucosa, and the results obtained were compared with those of another series of 52 patients (Group B) where dacryocystorhinostomy was performed with suturing only the anterior flaps, whereas posterior mucosal flaps were excised. Results: The success rate was evaluated by lacrimal patency to irrigation and relief of epiphora. Patency achieved in groups A and B was 94.4% and 96.2%, respectively. There was no statistically significant difference in success rate between the groups. Conclusion: Our study suggests that external dacryocystorhinostomy with suturing anterior and posterior flaps have no advantage over dacryocystorhinostomy with suturing only anterior flaps. Anastomosis by suturing only anterior flaps and excision of the posterior flaps is easier to perform and may improve the success rate of external dacryocystorhinostomy. PMID:24783915

  8. Segmentals and Global Foreign Accent: The Japanese Flap in EFL.

    ERIC Educational Resources Information Center

    Riney, Timothy J.; Takada, Mari; Ota, Mitsuhiko

    2000-01-01

    Reports the results of research on the extent to which global foreign accent in English is related to a discrete segmental feature of pronunciation, substitution of the Japanese flap for /l/ and /r/ in two phonological environments. Results showed a strong negative correlation between a nativelike accent and flap substitution. (Author/VWL)

  9. Outcome after free flap reconstruction of the heel.

    PubMed

    Durham, J W; Saltzman, C L; Steyers, C M; Miller, B A

    1994-05-01

    We reviewed six free flap reconstructions of the weight-bearing surface of the heel. Patients were seen for clinical evaluation at a mean follow-up of 4.7 years (range 2.7-6.0 years). Functional results using a modified Boston Children's Hospital Ankle Score were 33% excellent, 33% good, 17% fair, and 17% poor. The excellent functional results were related to the absence of chronic draining flap ulcers. All flaps lacked protective sensation by Semmes-Weinstein monofilament testing. Weightbearing plantar pressures in the flaps were elevated in all patients. Sequential radiographs from the time of flap coverage revealed the development of a bony protuberance (stalactite) projecting from the undersurface of the calcaneus in all patients with injuries to the plantar cortex of the calcaneus. In patients with flap ulceration, these stalactites projected into the ulcer at the site of maximum plantar pressure. A combination of loss of plantar calcaneal integrity, elevated pressure concentrations, and flap insensitivity appear causally related to the development of heel free flap ulceration and outcome.

  10. [The dorsoradial flap: a new flap for hand reconstruction. Anatomical study and clinical applications].

    PubMed

    Bakhach, J; Sentucq-Rigal, J; Mouton, P; Boileau, R; Panconi, B; Guimberteau, J-C

    2006-02-01

    The authors report a new cutaneous flap harvested from the dorsal and distal quarter of the forearm: the dorsoradial flap. The vascularisation type of the cutaneous paddle belongs this flap to the anterograde and axial family flaps. The anatomical study carried out on thirty six fresh cadaver upper arms showed a constant and a consistent cutaneous collateral branch of the radial artery which arises at the apex of the first intermetacarpal space. Two anatomical types were recorded according to the origin of the dorsoradial artery: type I (84% of cases), the vessel arises directly from the radial artery; type II (16% of cases), it arises from a common trunk with the first dorsal intermetacarpal artery. Those anatomical findings does not influence the flap operative technique, the flap design and the location of the pedicle pivot point. The dorsoradial artery emerges vertically from the apex of the first intermetacarpal space, crosses the angle between the extensor pollicis longus tendon laterally and the extensor carpi radialis longus tendon medially and turns proximally towards the distal radio-ulnar joint. Over the dorsal aspect of the wrist, the dorsoradial artery enters the subcutaneous tissue, runs parallel to the extensor pollicis longus tendon at three millimeters in a medial position, passes over the medial collateral branch of the superficial radial nerve and irrigates all the distal and dorsal quarter of the forearm. The artery is consistently accompanied by two comitantes veins, which assume the venous drainage of the cutaneous territory. The flap paddle is designed over the distal dorsal forearm quarter, between the dorsal crease of the wrist distally, the ulnar crest medially and the radial crest laterally. All this skin territory can be harvested and supplied by the dorsoradial pedicle, but we always should deal with the needs of the defects reconstruction and the morbidity of the donor site. The vascular pedicle is outlined between the distal radio

  11. Vaginal reconstruction using perineal-thigh flaps with subcutaneous pedicle.

    PubMed

    Chen, Z; Chen, C; Chen, M; Zhang, J; Wu, N; Wang, J

    1991-03-01

    A technique of vaginal reconstruction using bilateral, perineal-thigh flaps with subcutaneous pedicle is described. In this procedure, the flaps were raised bilaterally and introduced into an artificial space between the urinary bladder and rectum. The blood supply for the flaps flows from the perineal artery through anastomotic branches to the external pudendal artery. The authors used the technique on four patients, and all the flaps survived entirely. There was no complication. According to a more than two-year follow-up survey, the reconstructed vaginas are expansible and contract little. No stent is needed. There is good sensitivity in the wall of the artificial vagina because sensory nerves run through the flaps.

  12. A method for calculating externally blown flap noise

    NASA Technical Reports Server (NTRS)

    Fink, M. R.

    1978-01-01

    Several basic noise components were described. These components are: (1) compact lift dipoles associated with the wing and flaps; (2) trailing edge noise associated with the last trailing edge; and (3) quadrupole noise associated with the undeflected exhaust jet and the free jet located downstream of the trailing edge. These noise components were combined to allow prediction of directivity and spectra for under the wing (UTW) slotted flaps with conventional or mixer nozzles, UTW slotless flaps, upper surface blowing (USB) slotless flaps, and engine in front of the wing slotted flaps. A digital computer program listing was given for this calculation method. Directivities and spectra calculated by this method were compared with free field data for UTW and USB configurations. The UTRC method best predicted the details of the measured noise emission, but the ANOP method best estimated the noise levels directly below these configurations.

  13. Study of Flapping Flight Using Discrete Vortex Method Based Simulations

    NASA Astrophysics Data System (ADS)

    Devranjan, S.; Jalikop, Shreyas V.; Sreenivas, K. R.

    2013-12-01

    In recent times, research in the area of flapping flight has attracted renewed interest with an endeavor to use this mechanism in Micro Air vehicles (MAVs). For a sustained and high-endurance flight, having larger payload carrying capacity we need to identify a simple and efficient flapping-kinematics. In this paper, we have used flow visualizations and Discrete Vortex Method (DVM) based simulations for the study of flapping flight. Our results highlight that simple flapping kinematics with down-stroke period (tD) shorter than the upstroke period (tU) would produce a sustained lift. We have identified optimal asymmetry ratio (Ar = tD/tU), for which flapping-wings will produce maximum lift and find that introducing optimal wing flexibility will further enhances the lift.

  14. Propeller flaps: a review of indications, technique, and results.

    PubMed

    D'Arpa, Salvatore; Toia, Francesca; Pirrello, Roberto; Moschella, Francesco; Cordova, Adriana

    2014-01-01

    In the last years, propeller flaps have become an appealing option for coverage of a large range of defects. Besides having a more reliable vascular pedicle than traditional flap, propeller flaps allow for great freedom in design and for wide mobilization that extend the possibility of reconstructing difficult wounds with local tissues and minimal donor-site morbidity. They also allow one-stage reconstruction of defects that usually require multiple procedures. Harvesting of a propeller flap requires accurate patient selection, preoperative planning, and dissection technique. Complication rate can be kept low, provided that potential problems are prevented, promptly recognized, and adequately treated. This paper reviews current knowledge on propeller flaps. Definition, classification, and indications in the different body regions are discussed based on a review of the literature and on the authors' experience. Details about surgical technique are provided, together with tips to avoid and manage complications.

  15. Experimental investigation of a flapping wing model

    NASA Astrophysics Data System (ADS)

    Hubel, Tatjana Y.; Tropea, Cameron

    The main objective of this research study was to investigate the aerodynamic forces of an avian flapping wing model system. The model size and the flow conditions were chosen to approximate the flight of a goose. Direct force measurements, using a three-component balance, and PIV flow field measurements parallel and perpendicular to the oncoming flow, were performed in a wind tunnel at Reynolds numbers between 28,000 and 141,000 (3-15 m/s), throughout a range of reduced frequencies between 0.04 and 0.20. The appropriateness of quasi-steady assumptions used to compare 2D, time-averaged particle image velocimetry (PIV) measurements in the wake with direct force measurements was evaluated. The vertical force coefficient for flapping wings was typically significantly higher than the maximum coefficient of the fixed wing, implying the influence of unsteady effects, such as delayed stall, even at low reduced frequencies. This puts the validity of the quasi-steady assumption into question. The (local) change in circulation over the wing beat cycle and the circulation distribution along the wingspan were obtained from the measurements in the tip and transverse vortex planes. Flow separation could be observed in the distribution of the circulation, and while the circulation derived from the wake measurements failed to agree exactly with the absolute value of the circulation, the change in circulation over the wing beat cycle was in excellent agreement for low and moderate reduced frequencies. The comparison between the PIV measurements in the two perpendicular planes and the direct force balance measurements, show that within certain limitations the wake visualization is a powerful tool to gain insight into force generation and the flow behavior on flapping wings over the wing beat cycle.

  16. Experimental investigation of a flapping wing model

    NASA Astrophysics Data System (ADS)

    Hubel, Tatjana Y.; Tropea, Cameron

    2009-05-01

    The main objective of this research study was to investigate the aerodynamic forces of an avian flapping wing model system. The model size and the flow conditions were chosen to approximate the flight of a goose. Direct force measurements, using a three-component balance, and PIV flow field measurements parallel and perpendicular to the oncoming flow, were performed in a wind tunnel at Reynolds numbers between 28,000 and 141,000 (3-15 m/s), throughout a range of reduced frequencies between 0.04 and 0.20. The appropriateness of quasi-steady assumptions used to compare 2D, time-averaged particle image velocimetry (PIV) measurements in the wake with direct force measurements was evaluated. The vertical force coefficient for flapping wings was typically significantly higher than the maximum coefficient of the fixed wing, implying the influence of unsteady effects, such as delayed stall, even at low reduced frequencies. This puts the validity of the quasi-steady assumption into question. The (local) change in circulation over the wing beat cycle and the circulation distribution along the wingspan were obtained from the measurements in the tip and transverse vortex planes. Flow separation could be observed in the distribution of the circulation, and while the circulation derived from the wake measurements failed to agree exactly with the absolute value of the circulation, the change in circulation over the wing beat cycle was in excellent agreement for low and moderate reduced frequencies. The comparison between the PIV measurements in the two perpendicular planes and the direct force balance measurements, show that within certain limitations the wake visualization is a powerful tool to gain insight into force generation and the flow behavior on flapping wings over the wing beat cycle.

  17. 50 CFR Figure 16 to Part 223 - Escape Opening and Flap Dimensions for the Double Cover Flap TED

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Escape Opening and Flap Dimensions for the Double Cover Flap TED 16 Figure 16 to Part 223 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS...

  18. Submental flap as an alternative to microsurgical flap in intraoral post-oncological reconstruction in the elderly.

    PubMed

    Schonauer, Fabrizio; Di Martino, Annalena; Nele, Gisella; Santoro, Mariangela; Dell'Aversana Orabona, Giovanni; Califano, Luigi

    2016-09-01

    Oral and oropharyngeal squamous cell carcinoma (Scc) occur most commonly in middle-aged and elderly individuals. Free flaps are commonly used for reconstruction of extensive tumor resection defects in the oral cavity. Age alone is not an independent variable for increased risk in microvascular reconstruction; however operative time and ASA risk score correlated with medical complications but not with surgical complications. The submental island flap has proven to be a reliable alternative in reconstruction of composite oral cavity defects for its thinness, pliability and versatility in design, shared by the radial forearm free flap, and its advantageous donor site. The submental flap can be easily raised and involves shorter operative time and hospital stay compared to the free-flap procedure. It can be an excellent choice in patients with a high ASA risk score, moreover in elderly patients, where the potential complications linked to microsurgical procedures are avoided. PMID:27255573

  19. Pressure Distributions for the GA(W)-2 Airfoil with 20% Aileron, 25% Slotted Flap and 30% Fowler Flap

    NASA Technical Reports Server (NTRS)

    Wentz, W. H., Jr.; Fiscko, K. A.

    1978-01-01

    Surface pressure distributions were measured for the 13% thick GA(W)-2 airfoil section fitted with 20% aileron, 25% slotted flap and 30% Fowler flap. All tests were conducted at a Reynolds number of 2.2 x 10 to the 6th power and a Mach number of 0.13. Pressure distribution and force and moment coefficient measurements are compared with theoretical results for a number of cases. Agreement between theory and experiment is generally good for low angles of attack and small flap deflections. For high angles and large flap deflections where regions of separation are present, the theory is inadequate. Theoretical drag predictions are poor for all flap-extended cases.

  20. Aeroacoustic Measurements of a Wing-Flap Configuration

    NASA Technical Reports Server (NTRS)

    Meadows, Kristine R.; Brooks, Thomas F.; Humphreys, William M.; Hunter, William H.; Gerhold, Carl H.

    1997-01-01

    Aeroacoustic measurements are being conducted to investigate the mechanisms of sound generation in high-lift wing configurations, and initial results are presented. The model is approximately 6 percent of a full scale configuration, and consists of a main element NACA 63(sub 2) - 215 wing section and a 30 percent chord half-span flap. Flow speeds up to Mach 0.17 are tested at Reynolds number up to approximately 1.7 million. Results are presented for a main element at a 16 degree angle of attack, and flap deflection angles of 29 and 39 degrees. The measurement systems developed for this test include two directional arrays used to localize and characterize the noise sources, and an array of unsteady surface pressure transducers used to characterize wave number spectra and correlate with acoustic measurements. Sound source localization maps show that locally dominant noise sources exist on the flap-side edge. The spectral distribution of the noise sources along the flap-side edge shows a decrease in frequency of the locally dominant noise source with increasing distance downstream of the flap leading edge. Spectra are presented which show general spectral characteristics of Strouhal dependent flow-surface interaction noise. However, the appearance of multiple broadband tonal features at high frequency indicates the presence of aeroacoustic phenomenon following different scaling characteristics. The scaling of the high frequency aeroacoustic phenomenon is found to be different for the two flap deflection angles tested. Unsteady surface pressure measurements in the vicinity of the flap edge show high coherence levels between adjacent sensors on the flap-side edge and on the flap edge upper surface in a region which corresponds closely to where the flap-side edge vortex begins to spill over to the flap upper surface. The frequency ranges where these high levels of coherence occur on the flap surface are consistent with the frequency ranges in which dominant features

  1. Analysis of Non-symmetrical Flapping Airfoils

    NASA Astrophysics Data System (ADS)

    Beng Tay, Wee; Lim, Kah Bin

    2007-11-01

    Simulations have been done to assess the performance of different types of non-symmetrical airfoils on lift, thrust and propulsive efficiency under different flapping configurations at a Reynolds number of 10,000. The variables studied include the Stroudal number, reduced frequency, pitch angle and phase angle difference. In order to analyze the variables more efficiently, the Design of Experiments using the response surface methodology is applied. The simulation results show that besides the flapping configuration, airfoil shape also has a profound effect on the efficiency, thrust and lift production. The 4 factors have different levels of significance on the responses, indicating the shape of the airfoil plays a part as well. Thrust production depends more heavily on these parameters, rather than the shape of the airfoil. On the other hand, lift production is primarily dominated by its airfoil shape. Efficiency falls somewhere in between. Two-factor interactions among the variables also exist in efficiency and thrust production. Vorticity plots are analyzed to explain some of the results. Overall, the s1020 airfoil is able to provide relatively good efficiency and at the same time generate high thrust and lift force. These results can be used to help in the design of a better ornithopter's wing.

  2. Flapping flight: effect of asymmetric kinematics

    NASA Astrophysics Data System (ADS)

    Pande, Nakul; Krithivasan, Siddharth; K. R., Sreenivas

    2014-11-01

    Flapping flight has received considerable attention in the past with its relevance in the design of micro-air vehicles. In this regard, asymmetric flapping of wings offers simple kinematics. Nevertheless, it leads to symmetry-breaking in the flow field and generation of sustained lift. It has been observed previously with flow visualization experiments and Discrete Vortex Method (DVM) simulations that if the down-stroke time period is lesser than the up-stroke time, there is a net downward momentum imparted to the fluid. This is seen as a switching the flow field from a four-jet (symmetric) to a two-jet (asymmetric) configuration when the stroke-time ratio is progressively varied. This symmetry breaking has been studied experimentally using Particle Image Velocimetry (PIV) across a range of Reynolds Numbers and asymmetry ratios. Results are also corroborated with results from 3-D numerical simulations. Study helps in shedding light on the effectiveness of asymmetric kinematics as a lift generation mechanism.

  3. Uncertainty Analysis for a Jet Flap Airfoil

    NASA Technical Reports Server (NTRS)

    Green, Lawrence L.; Cruz, Josue

    2006-01-01

    An analysis of variance (ANOVA) study was performed to quantify the potential uncertainties of lift and pitching moment coefficient calculations from a computational fluid dynamics code, relative to an experiment, for a jet flap airfoil configuration. Uncertainties due to a number of factors including grid density, angle of attack and jet flap blowing coefficient were examined. The ANOVA software produced a numerical model of the input coefficient data, as functions of the selected factors, to a user-specified order (linear, 2-factor interference, quadratic, or cubic). Residuals between the model and actual data were also produced at each of the input conditions, and uncertainty confidence intervals (in the form of Least Significant Differences or LSD) for experimental, computational, and combined experimental / computational data sets were computed. The LSD bars indicate the smallest resolvable differences in the functional values (lift or pitching moment coefficient) attributable solely to changes in independent variable, given just the input data points from selected data sets. The software also provided a collection of diagnostics which evaluate the suitability of the input data set for use within the ANOVA process, and which examine the behavior of the resultant data, possibly suggesting transformations which should be applied to the data to reduce the LSD. The results illustrate some of the key features of, and results from, the uncertainty analysis studies, including the use of both numerical (continuous) and categorical (discrete) factors, the effects of the number and range of the input data points, and the effects of the number of factors considered simultaneously.

  4. Versatility of the buccinator myomucosal flap in atypical palate reconstructions.

    PubMed

    Franco, Diogo; Rocha, Diógenes; Arnaut, Marcio; Freitas, Renato; Alonso, Nivaldo

    2014-10-01

    Initially described for the treatment of cleft palate, the anatomical bases of the buccinator myomucosal flap were described by Bozola et al. (1989). A meticulous search found several reports of its use for the correction of post-palatoplasty oronasal fistulas, with only a few reports of its use for other palate-related pathologies. A retrospective analysis was undertaken of patients treated by the Plastic Surgery Units at the Rio de Janeiro Federal University Hospital (HU-UFRJ) and the São Paulo University Hospital (HC-USP), suffering from palatal lesions not associated with a cleft palate and treated through the use of buccinator myomucosal flaps. The average age was 47 years, with 70% of the patients being male. Assorted aetiologies were noted for palatal defects. When there was significant damage to the soft palate, a superior base pharyngeal flap was used. Of this total, in 71% of the cases only the buccinator myomucosal flap was used. In all cases, the flaps were unilateral, adequately covering the defects in question. The buccinator myomucosal flap is a good option for reconstructing medium to large palate defects, as it is a flap with good vascularization and dimension, in addition to an ample arc of rotation, with primary closure of the donor site, without adding significant morbidity.

  5. [Postoperative monitoring of microvascular flap repair with pulse oximetry--initial experience].

    PubMed

    Strauss, J M; Neukam, F W; Krohn, S; Schmelzeisen, R; Borchard, F

    1994-03-01

    The surgical success of microvascular free flaps or pedicled flaps depends on the function of the nutritive vessels. Complications such as thrombosis or vessel kinking, are dangerous and may result in flap loss. During the last decade, different methods were tested for their capability of monitoring flap perfusion. We report our preliminary experience with the continuous and non-invasive pulse oximetry by using a special reflection sensor positioned on the surface of the flap. PMID:8020852

  6. Preoperative color Doppler assessment in planning of gluteal perforator flaps.

    PubMed

    Isken, Tonguc; Alagoz, M Sahin; Onyedi, Murat; Izmirli, Hakki; Isil, Eda; Yurtseven, Nagehan

    2009-02-01

    Gluteal artery perforator flaps have gained popularity due to reliability, preservation of the muscle, versatility in flap design without restricting other flap options, and low donor-site morbidity in ambulatory patients and possibility of enabling future reconstruction in paraplegic patients. But the inconstant anatomy of the vascular plexus around the gluteal muscle makes it hard to predict how many perforators are present, what their volume of blood flow and size are, where they exit the overlying fascia, and what their course through the muscle will be. Without any prior investigations, the reconstructive surgeon could be surprised intraoperatively by previous surgical damage, scar formation, or anatomic variants.For these reasons, to confirm the presence and the location of gluteal perforators preoperatively we have used color Doppler ultrasonography. With the help of the color Doppler ultrasonography 26 patients, 21 men and 5 women, were operated between the years 2002 and 2007. The mean age of patients was 47.7 (age range: 7-77 years). All perforator vessels were marked preoperatively around the defect locations. The perforator based flap that will allow primary closure of the donor site and the defect without tension was planned choosing the perforator that showed the largest flow in color Doppler ultrasonography proximally. Perforators were found in the sites identified with color Doppler ultrasonography in all other flaps. In our study, 94.4% flap viability was ensured in 36 perforator-based gluteal area flaps. Mean flap elevation time was 31.9 minutes. We found that locating the perforators preoperatively helps to shorten the operation time without compromising a reliable viability of the perforator flaps, thus enabling the surgeon easier treatment of pressure sores.

  7. Aeroelastically deflecting flaps for shock/boundary-layer interaction control

    NASA Astrophysics Data System (ADS)

    Gefroh, D.; Loth, E.; Dutton, C.; Hafenrichter, E.

    2003-06-01

    An aeroelastic mesoflap system has been developed to improve the downstream flow properties of an oblique shock/boundary-layer interaction. The mesoflap system employs a set of small flaps over a cavity, whereby the flaps downstream of the interaction bend downward aeroelastically to bleed the flow and the upstream flaps bend upward to re-inject this same mass flow upstream. This recirculating system requires no net mass bleed and therefore has advantages for boundary layer control in external or mixed-compression supersonic aircraft inlets. In addition, the system may be applicable in other aerospace applications where boundary-layer control can help remedy the adverse effects of shock interactions. Several mesoflap systems have been fabricated and examined experimentally to investigate their aerodynamic and structural performance. Each mesoflap is rigidly attached to a spar on its upstream end while the remainder of the flap is free to deflect aeroelastically. The flap length is nominally a few boundary-layer thicknesses in dimension, while the flap thickness is small enough to allow tip deflections that are of the order of the boundary-layer momentum thickness. Experiments were conducted for a Mach 2.41 impinging oblique shock wave interaction with a turbulent boundary layer. Spanwise-centered laser Doppler velocimeter measurements indicate that certain mesoflap designs can show significant flow improvement as compared to the solid-wall case, including increased stagnation pressure recovery and a 7% reduction in boundary layer thickness and sonic thickness. However, one drawback of the mesoflap system is the potential for fatigue, which in some cases led to microcracking followed by flap failure. Structural design improvements to alleviate and avoid this problem included a lower profile spar design, substitution of Nitinol for aluminum as the flap material, and use of stress-relieving holes at the ends of the flap cut-outs.

  8. The flap by flap dissection in terminal ballistic applied to less lethal weapons.

    PubMed

    de Freminville, Humbert; Rongieras, Fréderic; Prat, Nicolas; Voiglio, Eric J

    2011-06-01

    Medical examiners often have to solve questions such as firing distance and bullet trajectory for lethal weapons. Knowledge in the field of terminal ballistics has increased during the last 30 years and layer by layer dissection reveals superficial wounds that can be linked with the permanent cavity. At the end of the 1990s, terminal ballistics also focused on less lethal weapons and their wounds. Here, 2 different less lethal weapons with single bullets were tested on nonembalmed and undressed cadavers (N = 26) at different ranges and speeds. We have developed a technique for dissection which we call flap by flap dissection that reveals the advantage of the bullet-skin-bone entity, the absence of wounds linking its components and range of less lethal weapons.

  9. Does body mass index matter while selecting the flap type for pharyngeal reconstructions?

    PubMed

    Calli, Caglar; Teknos, Theodoros N; Agrawal, Amit; Schuller, David E; Ozer, Enver; Songu, Murat

    2014-05-01

    The aim of our study was to investigate the effect of patient-related factors, such as the body mass index (BMI) and tumor size, in selecting the flap type for the reconstruction of pharyngeal defects. This retrospective review included 182 patients with pharyngeal defect reconstructions with free and pedicled flaps at the Ohio State University from January 2005 to December 2008. We conducted a retrospective comparison of variety of different flap reconstruction techniques. We compared different flap reconstruction with BMI and tumor size without functional outcome such as swallowing and speech data. Although there was no statistically significant correlation (P > 0.05) when comparing the free flaps with pedicled flaps according to the BMI and tumor size, there was an obvious tendency to prefer radial forearm free flap over anterolateral thigh free flap in patients who are overweight and those with obesity with a ratio of 32:3. In the same group of patients, a similar tendency was observed to prefer fibular free flap over iliac crest free flap with a ratio of 14:5, whereas the ratio was becoming 3:5 in favor of iliac crest free flap over fibular free flap in patients with BMI of 24 or lower. Despite the fact that surgeons' experience with a certain flap type is one of the most important factors while determining which flap to reconstruct, BMI might have a significant impact while selecting the free flap types for the reconstruction of pharyngeal defects.

  10. Bilateral anterolateral thigh flaps for large-volume breast reconstruction.

    PubMed

    Rosenberg, Jason J; Chandawarkar, Rajiv; Ross, Merrick I; Chevray, Pierre M

    2004-01-01

    Autologous tissue reconstruction of a large breast in patients who are not candidates for a TRAM flap is a difficult problem. We present a case report of the use of bilateral free anterolateral thigh (ALT) flaps for immediate reconstruction of a unilateral large breast in a patient who had a previous abdominoplasty. Use of ALT flaps allows two or three surgical teams to work simultaneously, does not require intraoperative patient repositioning, has minimal donor-site morbidity, and can provide ample malleable soft tissue for breast reconstruction. These are advantages compared to the use of gluteal donor sites. The disadvantages include more conspicuous donor-site scarring on the anterior thighs.

  11. Extracorporeal Free Flap Perfusion in Case of Prolonged Ischemia Time

    PubMed Central

    Präbst, K.; Beier, J. P.; Meyer, A.; Horch, R. E.

    2016-01-01

    Summary: In free flap surgery, a clinically established concept still has to be found for the reduction of ischemia-related cell damage in the case of prolonged ischemia. Although promising results using extracorporeal free flap perfusion in the laboratory have been published in the past, until now this concept has not yet paved its way into clinical routine. This might be due to the complexity of perfusion systems and a lack of standardized tools. Here, we want to present the results of the first extracorporeal free flap perfusion in a clinical setting using a simple approach without the application of a complex perfusion machinery. PMID:27200244

  12. Spectacles under Pedicles: Eyewear Modification with the Paramedian Forehead Flap

    PubMed Central

    Qu, Linda T.; Kelpin, John P.; Komorowska-Timek, Ewa

    2016-01-01

    Summary: The paramedian forehead flap is a widely used method of nasal reconstruction. The flap requires a bridge of tissue from forehead to the nose, for a period of 2 to 3 weeks, before it can be divided at a second procedure. During this time, patients often have difficulty positioning and wearing their eyewear underneath the pedicle of the flap. Here we present a novel approach to the problem. It requires only a simple modification to the patient’s eyewear and greatly facilitates wear and removal.

  13. Latissimus dorsi flap remains an excellent choice for breast reconstruction.

    PubMed

    Sternberg, Erez G; Perdikis, Galen; McLaughlin, Sarah A; Terkonda, Sarvam P; Waldorf, James C

    2006-01-01

    Latissimus dorsi flap has been unfairly relegated to a second option in breast reconstruction. One hundred consecutive latissimus dorsi muscle flaps (LDMF) with tissue-expander reconstruction were studied, mean follow-up 34.5 months (range, 1-175), 50 immediate, 50 delayed. With attention to a few technical details, excellent esthetic, soft reconstructions were achieved. Complications included 1 partial flap loss; 2 patients required inframammary fold revision; and 6 patients required surgery for capsular contracture. Donor-site seroma occurred in 34 patients; 6 required operative revision. Results were similar in the immediate versus the delayed groups. LDMF remains an esthetic, reliable, safe reconstructive choice.

  14. Spectacles under Pedicles: Eyewear Modification with the Paramedian Forehead Flap.

    PubMed

    Qu, Linda T; Kelpin, John P; Eichhorn, Mitchell G; Komorowska-Timek, Ewa

    2016-08-01

    The paramedian forehead flap is a widely used method of nasal reconstruction. The flap requires a bridge of tissue from forehead to the nose, for a period of 2 to 3 weeks, before it can be divided at a second procedure. During this time, patients often have difficulty positioning and wearing their eyewear underneath the pedicle of the flap. Here we present a novel approach to the problem. It requires only a simple modification to the patient's eyewear and greatly facilitates wear and removal. PMID:27622084

  15. Spectacles under Pedicles: Eyewear Modification with the Paramedian Forehead Flap

    PubMed Central

    Qu, Linda T.; Kelpin, John P.; Komorowska-Timek, Ewa

    2016-01-01

    Summary: The paramedian forehead flap is a widely used method of nasal reconstruction. The flap requires a bridge of tissue from forehead to the nose, for a period of 2 to 3 weeks, before it can be divided at a second procedure. During this time, patients often have difficulty positioning and wearing their eyewear underneath the pedicle of the flap. Here we present a novel approach to the problem. It requires only a simple modification to the patient’s eyewear and greatly facilitates wear and removal. PMID:27622084

  16. Medicinal leeches used to salvage a traumatic nasal flap.

    PubMed

    Mortenson, B W; Dawson, K H; Murakami, C

    1998-12-01

    We report a case in which medicinal leeches (Hirudo medicinalis) were used to rescue a traumatic nasal flap from venous congestion and loss. A healthy 18-year-old had a bicycling accident and, in addition to other facial injuries, presented with a complex full thickness nasal laceration. After he had been resuscitated and the flap sutured, he was treated with two leeches four times a day for 48 h. His recovery was satisfactory and uncomplicated. Oral and maxillofacial surgeons should be familiar with the use of leeches, as they have a small but occasionally important role in the management of both traumatic and reconstructive flaps.

  17. Tolerance of gastric mucosal flap to postoperative irradiation

    SciTech Connect

    Devineni, V.R.; Hayden, R.; Fredrickson, J.; Sicard, G. )

    1991-05-01

    When malignant lesions of the oral cavity, base of tongue, and oropharynx are treated with radical resection, adequate reconstruction is required. The free gastric mucosal flap with microvascular transfer is being used with increasing frequency at Washington University Medical Center. Because of the advanced nature of the primary lesions, most patients also require postoperative radiation therapy. In this paper the tolerance of the gastric mucosal flap to postoperative radiation therapy is reviewed. The changes resulting from radiation therapy in the mucosal flap were found to be acceptable, and no major complications were encountered.

  18. Free fibula osteocutaneous flap with soleus muscle as a chimeric flap for reconstructing mandibular segmental defect after oral cancer ablation.

    PubMed

    Kuo, Yur-Ren; Shih, Hsiang-Shun; Chen, Chien-Chang; Boca, Radovan; Hsu, Yao-Chung; Su, Chih-Ying; Jeng, Seng-Feng; Wei, Fu-Chan

    2010-06-01

    In some cases, the fibula osteocutaneous flap may not provide sufficient soft tissue for obliterating dead space after tumor ablation. This report describes a modified fibula osteocutaneous flap using a portion of soleus muscle to reduce postoperative complications. This study analyzed 20 patients who underwent ablative oral cancer surgery with mandibular segmental defect between September 2005 and June 2007. Of total, 17 cases were mandible complex defects and 3 were composite defects. Of total, 18 were men and 2 were women, respectively. Age range was 30 to 74 years, and mean age was 53 years. The procedure entailed harvest of chimeric fibula flap with skin paddle and bone segment composed of a sheet of soleus muscle (7 x 4 to 12 x 5 cm in size) originating from the perforator branch of the peroneal artery. The soleus muscle was used to obliterate the dead space of the mouth floor and cheek-neck area. All flaps survived except 1 failure due to venous insufficiency. The submandibular and chin area exhibited mild swelling at the submandibular area early postoperatively. Patients had achieved satisfactory contour without donor site morbidity at a mean 12-months of follow-up. Complications included 2 flaps requiring reoperation due to the flap pedicle compromised. One flap was successfully salvaged but the other failed. Two cases of orocutaneous fistula-induced infection recovered after conservative treatment. Donor site assessment revealed a satisfactory outcome without major donor site morbidity. This refinement in mandibular reconstructive surgery substantially reduces postoperative complications.

  19. Knee extensor loss and proximal tibial soft tissue defect managed successfully with simultaneous medial gastrocnemius flap, saphenous fasciocutaneous flap and medial hemisoleus flap: a case report

    PubMed Central

    2013-01-01

    Introduction Open fractures of the proximal tibia often pose serious challenges to the treating orthopedic surgeon. Management of these complex injuries becomes difficult if they are associated with damage to the extensor mechanism and an exposed knee joint. The scenario becomes more difficult to manage when the soft tissue defect extends to the middle third of the leg. We report a case where we used an extended medial gastrocnemius flap in combination with a saphenous artery fasciocutaneous flap and a medial hemisoleus flap for treatment of an infected proximal tibia fracture with loss of the extensor mechanism and soft tissue defect. To the best of our knowledge, combined use of these three flaps for the management of such injuries has not been reported elsewhere to date. Case presentation A 28-year-old Indian man presented to our Out-patient Department with complaints of pain and pus discharge from his left proximal leg for four weeks. He had sustained an open fracture of his left proximal tibia in a road traffic accident five weeks ago and had been operated on elsewhere. He had a stiff, painful knee with an infected wound of 4×4cm over the proximal third of his leg exposing infected, necrotic patellar tendon. He was successfully managed with debridement and simultaneously elevated flaps as described. Conclusions This procedure avoids the donor site morbidity associated with free flaps harvested from sites distant from the site of injury, and also does not need the expertise of microvascular reconstruction. To the best of our knowledge, this is also the first report of the combined use of three local flaps for knee extensor reconstruction and soft tissue coverage around the knee. PMID:23506268

  20. Soap Films Burst Like Flapping Flags

    NASA Astrophysics Data System (ADS)

    Lhuissier, Henri; Villermaux, Emmanuel

    2009-07-01

    When punctured, a flat soap film bursts by opening a hole driven by liquid surface tension. The hole rim does not, however, remain smooth but soon develops indentations at the tip of which ligaments form, ultimately breaking and leaving the initially connex film into a mist of disjointed drops. We report on original observations showing that these indentations result from a flaglike instability between the film and the surrounding atmosphere inducing an oscillatory motion out of its plane. Just like a flag edge flaps in the wind, the film is successively accelerated on both sides perpendicularly to its plane, inducing film thickness modulations and centrifuging liquid ligaments that finally pinch off to form the observed spray. This effect exemplifies how the dynamics of fragile objects such as thin liquid films is sensitive to their embedding medium.

  1. Oblique waves lift the flapping flag.

    PubMed

    Hœpffner, Jérôme; Naka, Yoshitsugu

    2011-11-01

    The flapping of the flag is a classical model problem for the understanding of fluid-structure interaction: How does the flat state lose stability? Why do the nonlinear effects induce hysteretic behavior? We show in this Letter that, in contrast with the commonly studied model, the full three-dimensional flag with gravity has no stationary state whose stability can be formally studied: The waves are oblique and must immediately be of large amplitude. The remarkable structure of these waves results from the interplay of weight, geometry, and aerodynamic forces. This pattern is a key element in the force balance which allows the flag to hold and fly in the wind: Large amplitude oblique waves are responsible for lift. PMID:22181612

  2. Sinking skin flap syndrome in glioblastoma.

    PubMed

    Kamiya-Matsuoka, Carlos; Shroff, Sheetal; Tatsui, Claudio E; Tremont-Lukats, Ivo W; Gilbert, Mark R

    2014-01-01

    Sinking skin flap syndrome (SSFS) is a rare neurological complication in patients with traumatic haemorrhage, stroke or cerebral oedema who undergo decompressive craniectomy to relieve increased intracranial pressure. Hallmark of SSFS is the sinking of the scalp to a plane lower than the edges of the skull defect in the setting of neurological deterioration. Our objective is to report that SSFS can present after small craniotomy without cerebral cortex compression and to share our diagnostic/therapeutic approach. A 62-year-old woman with a glioblastoma developed SSFS after a small craniectomy and tumour resection without cerebral cortex compression but a decrease in the surgical cavity volume. Brain MRI showed decreased size of the surgical cavity. Interestingly, the patient also developed posterior reversible encephalopathy syndrome (PRES). This case highlights an atypical presentation of SSFS and the possible association with PRES. It also illustrates how an early cranioplasty can successfully reverse SSFS. PMID:25398923

  3. Oblique waves lift the flapping flag.

    PubMed

    Hœpffner, Jérôme; Naka, Yoshitsugu

    2011-11-01

    The flapping of the flag is a classical model problem for the understanding of fluid-structure interaction: How does the flat state lose stability? Why do the nonlinear effects induce hysteretic behavior? We show in this Letter that, in contrast with the commonly studied model, the full three-dimensional flag with gravity has no stationary state whose stability can be formally studied: The waves are oblique and must immediately be of large amplitude. The remarkable structure of these waves results from the interplay of weight, geometry, and aerodynamic forces. This pattern is a key element in the force balance which allows the flag to hold and fly in the wind: Large amplitude oblique waves are responsible for lift.

  4. Vortex Flap Technology: a Stability and Control Assessment

    NASA Technical Reports Server (NTRS)

    Carey, K. M.; Erickson, G. E.

    1984-01-01

    A comprehensive low-speed wind tunnel investigation was performed of leading edge vortex flaps applied to representative aircraft configurations. A determination was made of the effects of analytically- and empirically-designed vortex flaps on the static longitudinal and lateral-directional aerodynamics, stability, and control characteristics of fighter wings having leading-edge sweep angles of 45 to 76.5 degrees. The sensitivity to several configuration modifications was assessed, which included the effects of flap planform, leading- and trailing-edge flap deflection angles, wing location on the fuselage, forebody strakes, canards, and centerline and outboard vertical tails. Six-component forces and moments, wing surface static pressure distributions, and surface flow patterns were obtained using the Northrop 21- by 30-inch low-speed wind tunnel.

  5. Optimization of Kinematics of a Flapping Wing Mechanism

    NASA Astrophysics Data System (ADS)

    George, Ryan; Thomson, Scott; Mattson, Christopher; Colton, Mark; Tree, Mike

    2010-11-01

    Flapping flight offers several potential advantages over conventional fixed wing flight, such as agility and maneuverability in confined spaces, potentially decreased noise and detectability, and hovering capability. In this presentation, a water tunnel-based flapping wing apparatus is introduced that allows for arbitrary wing trajectories in three rotational degrees of freedom and simultaneous measurements of lift and thrust production. An optimal flapping trajectory for takeoff is found using hardware-in-the-loop optimization methodology. Wing motion derived from high-speed imaging of a ladybug during takeoff is used as a first iteration of the hardware-in-the-loop optimization. Using real-time force measurements and a gradient-based optimization approach, the algorithm searches for the optimal trajectory for a variety of parameters such as lift or efficiency. Hardware performance is assessed. Results from the optimization routine, including the final flapping trajectory are reported for both rigid and compliant wings.

  6. Buccinator Myomucosal Flap for Treatment of Osteoradionecrosis of the Mandible.

    PubMed

    Woo, Seung Hoon

    2016-03-01

    The use of a myomucosal flap from the buccinator muscle is a valuable reconstruction method for intraoral defects. In this paper, we report the clinical advantages of using a buccinator myomucosal flap for the treatment of partial mandibular defects caused by osteoradionecrosis. We implemented a buccinator myomucosal flap for the reconstruction of a partial mandibular defect in a 55-year-old man with tonsil cancer and partial mandibular defects caused by osteoradionecrosis. The total operating time was 90 minutes. Twelve months after the reconstruction, the patient remains free of disease. A buccinator myomucosal flap can be used for the reconstruction of partial mandibular defects caused by osteoradionecrosis. It is a reliable method for reconstructing small mandibular defects.

  7. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... wing flap control lever settings corresponding to those positions must be positively located such that a definite change of direction of movement of the lever is necessary to select settings beyond...

  8. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... wing flap control lever settings corresponding to those positions must be positively located such that a definite change of direction of movement of the lever is necessary to select settings beyond...

  9. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... wing flap control lever settings corresponding to those positions must be positively located such that a definite change of direction of movement of the lever is necessary to select settings beyond...

  10. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... wing flap control lever settings corresponding to those positions must be positively located such that a definite change of direction of movement of the lever is necessary to select settings beyond...

  11. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... wing flap control lever settings corresponding to those positions must be positively located such that a definite change of direction of movement of the lever is necessary to select settings beyond...

  12. Splash jet and slamming generated by a rotating flap

    NASA Astrophysics Data System (ADS)

    Sun, S. Y.; Sun, S. L.; Ren, H. L.; Wu, G. X.

    2015-09-01

    The hydrodynamic problem of slamming generated by a rotating flap, commonly known as Oyster in the wave energy sector, plunging into water, is analysed based on the incompressible velocity potential theory. The problem is solved through the boundary element method in the time domain. Two typical case studies are undertaken. One is the flap plunging into calm water and the other into an incoming wave. The splash jet formed during the flap plunging is included in the simulation. When the jet meets the main flow, it is treated through the domain decomposition method without taking account the secondary impact, which is similar to the mathematical method of Riemann's second sheet in the complex plane. The problem is solved in each non-overlapping subdomain, and the velocity and pressure continuity condition is imposed on the interface of the subdomains. Detailed results for the flap plunging into water with different velocities or accelerations are provided. The gravity and wave effects are also investigated.

  13. Transfer of free fillet lateral arm flap for facial reconstruction.

    PubMed

    Bayram, Fazli Cengiz; Dadaci, Mehmet; Ince, Bilsev; Altuntas, Zeynep

    2014-07-01

    We describe a 16-year-old male patient who had a major right facial degloving injury resulting in a soft-tissue defect with exposed zygoma as well as temporal and frontal bones. Multiple operations were undertaken in a staged manner for reconstruction. Lateral arm free fillet flap transfer was initially performed with fixation of bones with miniplates, which is followed by flap debulking, lateral canthopexy, scalp tissue expansion for hairline reconstruction, as well as ear reconstruction with costal cartilage and local flap techniques. After a follow-up period of 2 years, a good and impressive reconstructive result was achieved through the use of multiple contemporary reconstructive procedures after a successful free fillet flap transfer from an amputated part. PMID:25006958

  14. Flap motion of helicopter rotors with novel, dynamic stall model

    NASA Astrophysics Data System (ADS)

    Han, Wei; Liu, Jie; Liu, Chun; Chen, Lei; Su, Xichao; Zhao, Peng

    2016-07-01

    In this paper, a nonlinear flapping equation for large inflow angles and flap angles is established by analyzing the aerodynamics of helicopter blade elements. In order to obtain a generalized flap equation, the Snel stall model was first applied to determine the lift coefficient of the helicopter rotor. A simulation experiment for specific airfoils was then conducted to verify the effectiveness of the Snel stall model as it applies to helicopters. Results show that the model requires no extraneous parameters compared to the traditional stall model and is highly accurate and practically applicable. Based on the model, the relationship between the flapping angle and the angle of attack was analyzed, as well as the advance ratio under the dynamic stall state.

  15. Wing compliance in self-propelled flapping flyers

    NASA Astrophysics Data System (ADS)

    Ramananarivo, Sophie; Thiria, Benjamin; Godoy-Diana, Ramiro

    2010-11-01

    Wing flexibility governs the flying performance of flapping wing flyers. Here we use the self-propelled flapping-wing model mounted on a "merry-go-round" described by Thiria and Godoy-Diana (Phys. Rev. E 82, 015303, 2010) to investigate the effect of chord-wise wing compliance on the propulsive performance of the system. The bending of the wings, which is driven mainly by wing inertia in the present experiments, redistributes the aerodynamic forces engendered by the flapping motion and improves the efficiency of the system for a wide range of wing flexibilities and flapping frequencies. A detailed analysis of the phase dynamics between the leading and trailing edges of the wings allows us to pinpoint the mechanisms that limit the beneficial effect of wing compliance.

  16. Noninvasive Free Flap Monitoring Using Eulerian Video Magnification

    PubMed Central

    Liu, Yuan Fang; Vuong, Christopher; Walker, Paul Charles; Peterson, Nathaniel Ray; Inman, Jared Christian; Filho, Pedro Alcantara Andrade; Lee, Steve Choon-Sung

    2016-01-01

    Eulerian Video Magnification (EVM) can enhance subtle changes in videos to reveal what was once invisible to the naked eye. In this proof of concept study, we investigated using EVM as a novel form of free flap monitoring. Free flaps with skin paddles were filmed in the operating room with manipulation of their pedicles. In a representative 77-year-old female who received a latissimus dorsi-serratus-rib composite free flap, EVM was able to detect blockage of arterial or venous supply instantaneously, providing a visible representation through degree of color change in videos. EVM has the potential to serve as a powerful free flap monitoring tool with the benefit of being noninvasive, sensitive, easy-to-use, and nearly cost-free. PMID:27092284

  17. Post-facelift flap necrosis treatment using charged polystyrene microspheres

    PubMed Central

    Weissman, Oren; Farber, Nimrod; Remer, Eric; Tessone, Ariel; Trivizki, Omer; Bank, Jonathan; Winkler, Eyal; Zilinsky, Isaac; Haik, Josef

    2013-01-01

    BACKGROUND: Flap necrosis following facial rhytidectomy constitutes a vexing and grievous complication to the patient and the surgeon. Treatment modalities that can expedite wound healing and re-epithelialization rates are highly desired. OBJECTIVES: To assess wound healing and re-epithelialization rates of open wounds following postrhytidectomy flap necrosis treated with commercially available charged polystyrene microspheres (Polyheal-1, Polyheal Ltd, Israel). METHODS: Flap necrosis following rhytidectomy with open wounds in three female patients were treated using dressings soaked with Polyheal-1. Wound closure rates were documented. RESULTS: The wounds demonstrated both accelerated granulation tissue formation and rapid re-epithelialization rates. No complications or side effects were encountered. CONCLUSIONS: Charged polystyrene microspheres may offer a new and efficacious way to treat open wounds due to flap necrosis following facial rhytidectomy. Further research with larger patient numbers is still needed to verify these findings. PMID:24431937

  18. Vascularized Nasoseptal Flap for Medial Orbital Wall Reconstruction.

    PubMed

    Turel, Mazda K; Chin, Christopher J; Vescan, Allan D; Gentili, Fred

    2016-09-01

    With the use and efficacy of the vascularized nasoseptal flap, its indications are also expanding. Due to its relative ease of harvesting and no significant impairment in the long-term sinonasal quality of life, the flap has been used for a number of other purposes apart from its originally proposed use in reconstruction of the anterior cranial fossa, sella, and the clivus. Its use may negate the need of another incision to obtain fat or fascia. The authors describe the case of a 47-year-old lady who underwent endoscopic excision of a medially placed orbital intraconal hemangioma who presented to us with very poor vision in the left eye. The large medial orbital defect was reconstructed with a vascularized pedicled nasoseptal flap from the ipsilateral side. The patient made an excellent visual and sino-nasal recovery. This patient highlights a unique use for the proliferating indications for the use of the nasoseptal flap. PMID:27428902

  19. High-flaps for natural laminar flow airfoils

    NASA Technical Reports Server (NTRS)

    Morgan, Harry L.

    1986-01-01

    A review of the NACA and NASA low-drag airfoil research is presented with particular emphasis given to the development of mechanical high-lift flap systems and their application to general aviation aircraft. These flap systems include split, plain, single-slotted, and double-slotted trailing-edge flaps plus slat and Krueger leading-edge devices. The recently developed continuous variable-camber high-lift mechanism is also described. The state-of-the-art of theoretical methods for the design and analysis of multi-component airfoils in two-dimensional subsonic flow is discussed, and a detailed description of the Langley MCARF (Multi-Component Airfoil Analysis Program) computer code is presented. The results of a recent effort to design a single- and double-slotted flap system for the NASA high speed natural laminar flow (HSNLF) (1)-0213 airfoil using the MCARF code are presented to demonstrate the capabilities and limitations of the code.

  20. Late traumatic flap displacement after laser in situ keratomileuisis.

    PubMed

    Franklin, Quentin J; Tanzer, David J

    2004-04-01

    Laser in situ keratomileusis (LASIK) has become the community standard in corneal refractive surgery and is being performed by surgeons in the Army, Navy, and Air Force. LASIK differs from photorefractive keratectomy (PRK) in that a partial-thickness corneal flap is created in the LASIK procedure before removing a microscopic amount of corneal tissue, whereas no flap creation is required in PRK. The benefits of LASIK include minimal discomfort after surgery, as well as a much faster return of visual function. PRK involves a surface ablation and therefore heals differently, involving more discomfort and a slower return of functional vision. LASIK flap integrity is a concern to anyone undergoing the procedure, as well as for those making recommendations on the best form of refractive surgery for military personnel. A case report and a review of the literature are presented on the identification and management of LASIK flap trauma.

  1. Development of Variable Camber Continuous Trailing Edge Flap System

    NASA Technical Reports Server (NTRS)

    Urnes, Jim, Sr.; Nguyen, Nhan T.; Dykman, John

    2012-01-01

    This presentation describes the current status of the joint NASA/Boeing collaboration on the development of a variable camber continuous trailing edge flap system for use in wing shaping control for cruise drag reduction.

  2. Flap prefabrication and prelamination with tissue-engineered cartilage.

    PubMed

    Staudenmaier, Rainer; Hoang, T Nguyen; Kleinsasser, Norbert; Schurr, Christian; Frölich, Kathrin; Wenzel, Magdalene M; Aigner, Joachim

    2004-10-01

    In reconstructive surgery, the integration of tissue-engineered cartilage in a prefabricated free flap may make it possible to generate flaps combining a variety of tissue components, to meet the special requirements of particular defects. One aim of the present study was to investigate prefabrication of a microvascular free flap by implanting a vessel loop under a skin flap in a rabbit model. A second aim was to report on the authors' preliminary experiences in prelaminating prefabricated flaps with autologous tissue-engineered cartilage, in terms of matrix development, inflammatory reaction, and host-tissue interaction. The flap was prefabricated by implanting a vessel loop under a random-pattern abdominal skin flap. The tissue-engineered cartilage constructs were made by isolating chondrocytes from auricular biopsies. Following a period of amplification, the cells were seeded onto a non-woven scaffold made of a hyaluronic-acid derivative and cultivated for 2 weeks. One cell-biomaterial construct was placed beneath the prefabicated flap, and two additional constructs were placed subcutaneously and intramuscularly. In addition, a biomaterial sample without cells was placed subcutaneously to provide a control. All implanted specimens were left in position for 6 or 12 weeks. Neovascularization in the prefabricated flap and biomaterial construct was analyzed by angiography. After explantation, the specimens were examined by histologic and immunohistochemical methods. The prefabricated flaps showed a well-developed network of blood vessels between the implanted vessel loop and the original random-pattern blood supply. The tissue-engineered constructs remained stable in size and showed signs of tissue similar to hyaline cartilage, as evidenced by the expression of cartilage-specific collagen type II and proteoglycans. No inflammatory reactions were observed. The physiologic environment of the autologous rabbit model provided favorable conditions for matrix deposition

  3. Full-scale upper-surface-blown flap noise. [for short haul STOL aircraft

    NASA Technical Reports Server (NTRS)

    Heidelberg, L. J.; Homyak, L.; Jones, W. L.

    1975-01-01

    A highly noise-suppressed TF 34 engine was used to investigate the noise of several powered lift configurations involving upper-surface-blown (USB) flaps. The configuration variables were nozzle type (i.e. slot and circular with deflector), flap chord-length, and flap angle. The results of velocity surveys at both the nozzle exit and the flap trailing edge are used for correlation of the noise data. Configurations using a long flap design were 4 dB quieter than a short flap typical of current trends in USB flap design. The lower noise for the long flap is attributed primarily to the greater velocity decay of the jet at the flap trailing edge. The full-scale data revealed substantially more quadrupole noise in the region near the deflected jet than observed in previous sub-scale tests.

  4. Combined Use of Anterolateral Thigh and Gluteal Fold Flaps for Complex Groin Reconstruction.

    PubMed

    Fujiki, Masahide; Miyamoto, Shimpei; Arikawa, Masaki; Sakuraba, Minoru

    2015-10-01

    We present a case of an epithelioid sarcoma of the right groin in which wide resection resulted in a complex groin defect involving the full thickness of the abdominal wall and the perineum. We reconstructed the defect using a combination of pedicled anterolateral thigh (ALT) flap and gluteal fold flap. The functional and aesthetic results were satisfactory. The ALT flap with a robust iliotibial tract is the flap of choice for abdominal wall reconstruction; however, the area covered by the skin island of the flap is restricted because the skin island is tethered to the iliotibial tract. In such cases, a gluteal fold flap is ideal for an ALT flap. Therefore, using a combination of a pedicled ALT flap and a gluteal fold flap could be a reliable option for the reconstruction of a complex groin defect. PMID:26579347

  5. Clinical reliability of radial forearm free flap in repair of buccal defects

    PubMed Central

    2013-01-01

    Background The ideal method for buccal defects should provide good outcome of both function and appearance; our goal is to highlight the reliability of radial forearm flap in buccal reconstruction. Methods A retrospective study was conducted. From 2005 to 2012, 20 radial forearm flaps were used to repair the defects. We analyzed the superiority and reliability of the flap; in addition, we reviewed some related literature and made a comparison between radial forearm flap and platysma flap. Results All radial forearm flaps totally survived, but two flaps suffered venous obstruction, hematoma, respectively. Radial forearm flap preserved the original interincisal distance well. In our follow-up, all patients had sufficient mouth-opening width (mean: 4.3 cm). Conclusion Radial forearm flap is a reliable method for buccal defect reconstruction. PMID:23363472

  6. Flap Side Edge Liners for Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Khorrami, Mehdi R. (Inventor); Choudhari, Meelan M. (Inventor); Howerton, Brian M. (Inventor)

    2014-01-01

    One or more acoustic liners comprising internal chambers or passageways that absorb energy from a noise source on the aircraft are disclosed. The acoustic liners may be positioned at the ends of flaps of an aircraft wing to provide broadband noise absorption and/or dampen the noise producing unsteady flow features, and to reduce the amount of noise generated due to unsteady flow at the inboard and/or outboard end edges of a flap.

  7. [Reconstruction of the thumb using a forearm osseofasciocutaneous reverse flap].

    PubMed

    Jevtović, Dobrica; Dordević, Boban; Gacević, Milomir; Sijan, Goran

    2002-01-01

    This paper presents the experiences of the thumb reconstruction with osteofasciocutaneous reverse flap (OFCR flap). In the period between 1987 and 2000 the OFCR flap was used in 15 patients. The youngest of them was 18 and the oldest was 38 years of age. The average age was 25.4. All the patients had posttraumatic amputations. Defects on proximal phalangae and a part of metacarpal bone occurred in two cases. In one case there was an amputation on the base level of proximal phalanx and the metacarpophalangeal (MPH) joint was preserved. In all cases of reconstruction the OFCR flap was used, which included antebrachial skin nervs that were anastomosed with digital nerv. The flap nutrition was carried out through the reverse circulation of a. radialis, and the venous drainage through the comitant vein of a. radialis. Superficial veins were not anastomosed. Secondary defects were covered with a free skin graft. All the flaps survived. The bone graft was healed in the period of eight weeks. The sensibility of this flap was regained in the period of three to six months after the surgery. The distance of two-point discrimination (TPD) was increased for 30% compared to the same region on the other hand after six months. The opposition of the reconstructed thumb to the other fingers was possible, as well as abduction, adduction and normal grasp. The method of reconstruction of the amputated thumb with the OFCR flap was better than other classical methods because it allowed the reconstruction of all the structures in one surgical operation. The sensibility that was regained represented good protection from injuries. There were no functional damages on the secondary defect. The esthetic result was not good due to the lack of a fingernail. PMID:12557617

  8. Animal flight dynamics II. Longitudinal stability in flapping flight.

    PubMed

    Taylor, G K; Thomas, A L R

    2002-02-01

    Stability is essential to flying and is usually assumed to be especially problematic in flapping flight. If so, problems of stability may have presented a particular hurdle to the evolution of flapping flight. In spite of this, the stability of flapping flight has never been properly analysed. Here we use quasi-static and blade element approaches to analyse the stability provided by a flapping wing. By using reduced order approximations to the natural modes of motion, we show that wing beat frequencies are generally high enough compared to the natural frequencies of motion for a quasi-static approach to be valid as a first approximation. Contrary to expectations, we find that there is noting inherently destabilizing about flapping: beating the wings faster simply amplifies any existing stability or instability, and flapping can even enhance stability compared to gliding at the same air speed. This suggests that aerodynamic stability may not have been a particular hurdle in the evolution of flapping flight. Hovering animals, like hovering helicopters, are predicted to possess neutral static stability. Flapping animals, like fixed wing aircraft, are predicted to be stable in forward flight if the mean flight force acts above and/or behind the centre of gravity. In this case, the downstroke will always be stabilizing. The stabilizing contribution may be diminished by an active upstroke with a low advance ratio and more horizontal stroke plane; other forms of the upstroke may make a small positive contribution to stability. An active upstroke could, therefore, be used to lower stability and enhance manoeuvrability. Translatory mechanisms of unsteady lift production are predicted to amplify the stability predicted by a quasi-static analysis. Non-translatory mechanisms will make little or no contribution to stability. This may be one reason why flies, and other animals which rely upon non-translatory aerodynamic mechanisms, often appear inherently unstable.

  9. Intimal Flap Vegetation Following Aortic Root Re-dissection

    PubMed Central

    Osada, Hiroaki; Nakajima, Hiroyuki; Meshii, Katsuaki; Ohnaka, Motoaki

    2016-01-01

    A 75-year-old man who had undergone ascending aorta replacement for acute Type A aortic dissection presented with a recurring high fever. Transesophageal echocardiography revealed that a vegetation had formed on the re-dissected intimal flap of the noncoronary sinus of Valsalva. This didactic case suggests that antibiotic prophylactic measures be considered for aortic dissection flaps as for irregular valves susceptible to infective endocarditis.

  10. Code For Analysis Of Wing-And-Flap Systems

    NASA Technical Reports Server (NTRS)

    Darden, Christine M.; Carlson, Harry W.

    1990-01-01

    SUBAERF2 program developed to provide for analysis of subsonic aerodynamics and design by iteration of low-speed wing/flap systems. Based on linearized-theory lifting-surface solution but also accounts for some nonlinear characteristics. Effects of leading- and trailing-edge flaps included. New and improved version of programs described in LAR-13116 and LAR-12987, and replaces both of them. Written in FORTRAN V.

  11. Aerodynamics and flight performance of flapping wing micro air vehicles

    NASA Astrophysics Data System (ADS)

    Silin, Dmytro

    Research efforts in this dissertation address aerodynamics and flight performance of flapping wing aircraft (ornithopters). Flapping wing aerodynamics was studied for various wing sizes, flapping frequencies, airspeeds, and angles of attack. Tested wings possessed both camber and dihedral. Experimental results were analyzed in the framework of momentum theory. Aerodynamic coefficients and Reynolds number are defined using a reference velocity as a vector sum of a freestream velocity and a strokeaveraged wingtip velocity. No abrupt stall was observed in flapping wings for the angle of attack up to vertical. If was found that in the presence of a freestream lift of a flapping wing in vertical position is higher than the propulsive thrust. Camber and dihedral increased both lift and thrust. Lift-curve slope, and maximum lift coefficient increased with Reynolds number. Performance model of an ornithopter was developed. Parametric studies of steady level flight of ornithopters with, and without a tail were performed. A model was proposed to account for wing-sizing effects during hover. Three micro ornithopter designs were presented. Ornithopter flight testing and data-logging was performed using a telemetry acquisition system, as well as motion capture technology. The ability of ornithopter for a sustained flight and a presence of passive aerodynamic stability were shown. Flight data were compared with performance simulations. Close agreement in terms of airspeed and flapping frequency was observed.

  12. Compliant topology optimization for planar passive flap micro valve.

    PubMed

    Yoon, Gil Ho

    2014-10-01

    This paper reports the compliant topology optimization for planar passive flap micro valve considering fluid-structure interaction with a monolithic approach. Although flap valve type check valve is easy to manufacture and use for the applications for Bio/Nano/MEMS, its structural optimization has been seldom conducted so far. The size of the Bio/Nano/MEMS devices becomes smaller and the simple straight type micro valve structure is required to be optimized considering fluid speed. To address this optimization problem, the structural topology optimization scheme which designs optimal topologies is applied for a flap type check valve structure. To consider the coupling effects of fluid domain and structural domain, the monolithic finite element approach is employed. In the new analysis approach, solid domain is simulated by introducing the inverse permeability in the Navier-Stokes equation and the fluid stress filter in the linear elasticity equation. Also it is a new idea that fluid domain is simulated by finite elements with a weak Young's modulus in the linear elasticity equation. The mutual couplings between fluid and structure are considered by the introduction of the deformation tensor which is one of the basic concepts of the continuum mechanism. By distributing material properties inside a design domain for compliant flap, optimal flap structures can be constructed with different fluid speeds. By investigating the optimal layouts of several passive flap designs, we prove that the structural topology optimization can provide optimal layouts for Bio, Nano, and MEMS applications. PMID:25942830

  13. Temporalis myo-osseous flap: an experimental study

    SciTech Connect

    Antonyshyn, O.; Colcleugh, R.G.; Hurst, L.N.; Anderson, C.

    1986-03-01

    The present paper investigates the anatomy and vascularization of the temporalis myo-osseous flap. This is a calvarial bone flap that employs temporalis muscle and its distal pericranial extension as a pedicle. In six human cadavers the flap was raised as an island on the anterior deep temporal artery after transecting the zygomatic arch and coronoid process. Maximal mobilization was thus obtained, allowing rotation of the flap into the mouth for intraoral reconstruction. The arc of rotation and potential surgical applications were noted. A comparative study of the temporalis myo-osseous flap and free calvarial bone graft was then conducted in a rabbit model. Vascularization of the calvarial bone flap was confirmed by technetium scintigraphy performed on the first postoperative day. The uptake of fluorochrome labels immediately after transfer verified the adequacy of the periosteal circulation in maintaining viability and new osteoid formation throughout the full thickness of calvarial bone. The transplantation of free calvarial bone grafts was followed by necrosis of most cellular elements. This was demonstrated by an absence of fluorochrome uptake up to 19 days postoperatively and a predominance of empty lacunae and nonviable marrow.

  14. A triceps musculocutaneous flap for chest-wall defects

    SciTech Connect

    Hartrampf, C.R. Jr.; Elliott, L.F.; Feldman, S. )

    1990-09-01

    A posterior upper arm flap based on the profunda brachii vessels has been described to cover soft-tissue defects in the upper anterolateral chest. In our series, the posterior upper arm skin is elevated with the long head of the triceps muscle to cover seven chest-wall defects resulting from indolent postradiation open wounds following partial TRAM flap failure (n = 2), soft-tissue deficiencies following partial TRAM flap loss (n = 3), and primarily as an ancillary flap in TRAM flap breast reconstruction (n = 2). This flap also may be used to supply well-vascularized tissue in the regions of the shoulder, axilla, and posterolateral back. A prerequisite for this operation is redundant tissue of the upper arm often present in middle-aged women and in patients with lymphedema following mastectomy. In our series of seven patients, all donor sites were closed primarily, and there was no subjective functional deficit following transfer of the long head of the triceps muscle.

  15. Flap Conformations in HIV-1 Protease are Altered by Mutations

    NASA Astrophysics Data System (ADS)

    Fanucci, Gail; Blackburn, Mandy; Veloro, Angelo; Galiano, Luis; Fangu, Ding; Simmerling, Carlos

    2009-03-01

    HIV-1 protease (PR) is an enzyme that is a major drug target in the treatment of AIDS. Although the structure and function of HIV-1 PR have been studied for over 20 years, questions remain regarding the conformations and dynamics of the β-hairpin turns (flaps) that cover the active site cavity. Distance measurements with pulsed EPR spectroscopy of spin labeled constructs of HIV-1 PR have been used to characterize the flap conformations in the apo and inhibitor bound states. From the most probably distances and the breadth of the distance distribution profiles from analysis of the EPR data, insights regarding the flap conformations and flexibility are gained. The EPR results clearly show how drug pressure selected mutations alter the average conformation of the flaps and the degree of opening of the flaps. Molecular dynamics simulations successfully regenerate the experimentally determined distance distribution profiles, and more importantly, provide structural models for full interpretation of the EPR results. By combining experiment and theory to understand the role that altered flap flexibility/conformations play in the mechanism of drug resistance, key insights are gained toward the rational development of new inhibitors of this important enzyme.

  16. Effects of calcitriol on random skin flap survival in rats.

    PubMed

    Zhou, Kai-liang; Zhang, Yi-hui; Lin, Ding-sheng; Tao, Xian-yao; Xu, Hua-zi

    2016-01-01

    Calcitriol, a metabolite of vitamin D, is often used in osteoporosis clinics. However, the material has other bioactivities; for example, it accelerates angiogenesis, has anti-inflammatory properties, and inhibits oxidative stress. We investigated the effects of calcitriol in a random skin flap rat model. "McFarlane flap" models were established in 84 male Sprague Dawley rats, divided into two groups. One group received intraperitoneal injections of calcitriol (2 μg/kg/day) whereas control rats received intraperitoneal injections of saline. The percentage flap survival area and tissue water content were measured 7 days later, which showed that calcitriol improved flap survival area and reduced tissue edema. It also increased the mean vessel density and upregulated levels of VEGF mRNA/protein, both of which promote flap angiogenesis. Moreover, it decreased leukocyte and macrophage infiltration, reduced the inflammatory proteins IL1β and IL6, increased SOD activity, decreased MDA content, and upregulated the level of autophagy. Overall, our results suggest that calcitriol promotes skin flap survival by accelerating angiogenesis, having anti-inflammatory effects, reducing oxidative stress, and promoting autophagy. PMID:26732750

  17. Outcome of free digital artery perforator flap transfer for reconstruction of fingertip defects

    PubMed Central

    Zhu, Lei; Xu, Qingjia; Kou, Wei; Ning, Bin; Jia, Tanghong

    2014-01-01

    Background: Fingertip defect can be treated with many flaps such as random pattern abdominal flap, retrograde digital artery island flap, V-Y advancement flap, etc. However, swelling in the fingertip, dysfunction of sensation, flexion and extension contracture or injury in the hemi-artery of the finger usually occurs during the recovery phase. Recently, digital artery perforator flaps have been used for fingertip reconstructions. With the development of super microsurgery techniques, free flaps can be more effective for sensory recovery and durability of the fingertip. Materials and Methods: Six cases (six fingers) of fingertip defects were treated with free digital artery perforator flaps of appropriate size and shape from the proximal phalanx. During surgery, the superficial veins at the edge of flap were used as reflux vessels and the branches of the intrinsic nerve and dorsal digital nerve toward the flap were used as sensory nerves. The proximal segment of the digital artery (cutaneous branches) towards the flap was cut off to form the pedicled free flap. The fingertips were reconstructed with the free flap by anastomosing the cutaneous branches of digital artery in the flap with the distal branch or trunk of the digital artery, the flap nerve with the nerve stump and the veins of the flap with the digital artery accompanying veins or the superficial veins in the recipient site. Results: Six flaps survived with successful skin grafting. Patients were followed up for 6-9 months. The appearance and texture of the flaps was satisfactory. The feeling within the six fingers recovered to S4 level (BMRC scale) and the two point discrimination was 3-8 mm. Conclusion: Free digital artery perforator flap is suitable for repairing fingertip defect, with good texture, fine fingertip sensation and without sacrificing the branch of the digital artery or nerve. PMID:25404772

  18. Island Latissimus Dorsi Muscle Flap and a Perforator Flap in Repairing Post-Gunshot Thoracic Spine CSF Fistula: Case Presentation

    PubMed Central

    Wanjala, Nangole F.; Stanley, Khainga Ominde

    2015-01-01

    Persistent posttraumatic CSF fluid leakage may present a challenge to manage. Failure to address the leakage may result in complications such as meningitis, septicemia, radiculopathy, muscle weakness, and back pains. While the majority of the leakages may be managed conservatively, large dura defects as a result of gunshot wounds or motor vehicle accidents are best managed by surgical interventions. This may range from primary closure of the defect to fascial grafts, adhesive glues, and flaps. We present our experience with the use of flaps in a patient who had sustained such wounds in the thoracic spine. An island latissimus dorsal flap and a perforator fasciocutaneous flap were used to close the defect. Postoperatively the patient recovered well and the wounds healed without any complications. PMID:26491596

  19. Identification of independent risk factors for flap failure: A retrospective analysis of 1530 free flaps for breast, head and neck and extremity reconstruction.

    PubMed

    Las, David E; de Jong, Tim; Zuidam, J Michiel; Verweij, Norbert M; Hovius, Steven E R; Mureau, Marc A M

    2016-07-01

    Reconstructive microsurgery is a powerful method of treating various complex defects. However, flap loss remains a possibility, leading to additional surgery, hospitalisation and costs. Consequently, it is important to know which factors lead to an increased risk of flap failure, so that measures can be undertaken to reduce this risk. Therefore, we analysed our results over a 20-year period to identify risk factors for flap failure after breast, head and neck and extremity reconstruction. The medical files of all patients treated between 1992 and 2012 were reviewed. Patient characteristics, surgical data and post-operative complications were scored, and independent risk factors for flap loss were identified. Reconstruction with a total of 1530 free flaps was performed in 1247 patients. Partial and total flap loss occurred in 5.5% and 4.4% of all free flaps, respectively. In all flaps, signs of compromised flap circulation were a risk factor for flap failure. More specifically, the risk factors for flap failure in breast reconstruction were previous radiotherapy, venous anastomosis revision, gluteal artery perforator (GAP) flap choice and post-operative bleeding. In head and neck reconstruction, pulmonary co-morbidity and anastomosis to the lingual vein or superficial temporal artery were risk factors, whereas a radial forearm flap reduced the risk. In extremity reconstruction, diabetes, prolonged anaesthesia time and post-operative wound infection were risk factors. Independent pre-, intra- and post-operative risk factors for flap failure after microvascular breast, head and neck and extremity reconstruction were identified. These results may be used to improve patient counselling and to adjust treatment algorithms to further reduce the chance of flap failure.

  20. [Covering losses of cutaneous substance of the leg and foot using skin flaps. Apropos of 76 cases].

    PubMed

    Oberlin, C; Alnot, J Y; Duparc, J

    1988-01-01

    Between 1983 and 1987, 76 flap grafts were performed in the leg and foot. In general, 3 types of flap were used: --51 ipsilateral flaps, the majority of which were musculo-cutaneous flaps from the medial head of gastrocnemius (17 cases). --17 cross-leg flaps from the opposite limb, the majority of which were medial fascio-cutaneous flaps (13 cases). --8 free flaps, making use of microsurgical techniques. The indications for cross-leg flaps and free flaps have become more limited in favour of local regional pedicle flaps. The lower part of the leg and amputation stumps in the foot are easily covered by distal leg pedicle flaps and amputation stumps of the upper third of the leg can be covered by a flap of fascia lata with a distal pedicle based on the superolateral branches of the peri-articular plexus of the knee.

  1. The evaluation of flap growth and long-term results of pediatric mandible reconstructions using free fibular flaps.

    PubMed

    Temiz, Gökhan; Bilkay, Ufuk; Tiftikçioğlu, Yiğit Özer; Mezili, Candan Tevfik; Songür, Ecmel

    2015-05-01

    Currently, the free fibular flap is well accepted as the first choice for mandibular reconstruction. Achieving functional results in pediatric patients requires a different approach than that employed for mature patients. Because the pediatric craniofacial skeleton continues to grow, reconstruction is more challenging, and the long-term results can be different from those of adult patients. In this study, we sought to measure flap growth objectively in our series. Ten pediatric patients who underwent reconstruction with free fibular flaps were retrospectively reviewed. Flap growth was evaluated by comparing the intraoperative photographs with photographs of the control panoramic mandibular radiographs taken using photo-anthropometric techniques. The measurements were converted to proportionality indices (PI), and these indices were compared. Subsequent complications and functional results were also evaluated. The mean patient age was 11.8 years, and the mean follow up was 57.7 months. The mean preoperative PI value was 10.74  ±  2.47. The mean postoperative PI value was 12.52  ±  2.34. The mean difference between the preoperative and postoperative PI values was -1.78 ± 0.53. These photo-anthropometric data clearly illustrated the growth of the fibular flaps (P = 0.001). None of these patients exhibited nonunion of the fractures; however, one patient experienced a delayed union, one had chronic temporomandibular joint pain, and one had chronic temporomandibular joint luxation. In two patients, the inter-incisive measurements were below the third percentile, and two additional patients had grade 2 eating abilities, which can be regarded as poor. All of the patients had symmetric mandibular contours. Free fibular flaps continue to grow in pediatric patients. This flap is a "workhorse" flap in children because it adapts to the craniofacial skeleton via its ability to grow, and this ability results in subsequent good cosmetic and functional results. PMID

  2. Vector control of two-dimensional turbulent free jet by both-side flaps

    NASA Astrophysics Data System (ADS)

    Enokida, K.; Okamoto, T.

    1985-05-01

    This paper presents an experimental investigation of the characteristics of a two-dimensional turbulent jet deflected by the flaps attached at both sides of the nozzle. It was found that the deflection angle was nearly equal to the flap angle when the flap angle was less than the critical angle and it approached the deflection angle for one-side flap. And the length of potential core, decay of maximum velocity and spread of jet were varied with the flap angle, but were unchanged by the flap width.

  3. Innovative techniques in preventing and salvaging neurovascular pedicle flaps in reconstructive foot and ankle surgery.

    PubMed

    Zgonis, Thomas; Stapleton, John J

    2008-04-01

    Pedicle flaps to cover soft tissue defects of the foot, ankle, and lower extremity are invaluable. However, venous congestion and flap necrosis, a common complication, poses greater morbidity to the patient as few remaining options for attempted limb salvage remain. The authors discuss how to prevent flap failure by allowing close observation and strict offloading of the pedicle flap through current external fixation designs. This article also discusses the role of medicinal leeches in reestablishing blood flow through the pedicle flap to prevent tissue necrosis. In addition, the use of hydrosurgery as an innovative technique offers the surgeon another option if faced with pedicle flap necrosis. PMID:19825700

  4. Anterolateral thigh flap salvage following failed deep inferior epigastric artery perforator breast reconstruction

    PubMed Central

    Krochmal, Daniel J; Rebecca, Alanna M; Casey, William J; Smith, Anthony A

    2011-01-01

    The deep inferior epigastric artery perforator flap is an option for women desiring autologous tissue breast reconstruction. If this reconstruction fails, other autologous tissue flaps, including the gluteal artery perforator and latissimus dorsi flaps, may be used for salvage. The anterolateral thigh (ALT) flap offers adequate tissue volume for breast reconstruction, acceptable fat quality and a long vascular pedicle. Other advantages include obviating the need for intraoperative position changes and harvesting tissue outside of the radiation field. Two cases involving ALT flaps used in the setting of deep inferior epigastric artery perforator failure are presented with favourable results. A review of the anatomy of the ALT flap is included. PMID:22379371

  5. Three cross leg flaps for lower leg reconstruction of Gustilo type III C open fracture

    PubMed Central

    Sano, Kazufumi; Ozeki, Satoru; Sugimoto, Ichiro; Ogawa, Masato

    2016-01-01

    A 60 year old male had Gustilo type III C open fracture of the right lower leg. After radical debridement, the large open defect including certain loss of the bone tissue was successfully augmented and covered, by consecutive three cross-leg flaps, which consisted of the free rectus abdominis musculocutaneous flap, the fibula osteocutaneous flap and the conventional sural flap. Although indication for amputation or preservation is decided with multiple factors in each case, a strategic combination of cross-leg flap, free flap, external fixation and vascular delay could increase the potential of preservation of the lower leg with even disastrous Gustilo type III C. PMID:27293297

  6. Enhancement of flap survival and changes in angiogenic gene expression after AAV2-mediated VEGF gene transfer to rat ischemic flaps.

    PubMed

    Wang, Xiao Tian; Avanessian, Bella; Ma, Qiangzhong; Durfee, Heather; Tang, Yu Qing; Liu, Paul Y

    2011-01-01

    Necrosis of surgically transferred flaps due to ischemia is a serious wound problem. We evaluated the improvement of flap survival and changes in angiogenic gene expression profiles after transfer of the VEGF gene by means of adeno-associated virus type 2 (AAV2) vector to rat ischemic flaps. Thirty rats were divided into one experimental group, one AAV2-GFP group, and one saline group. AAV2-VEGF or AAV2-GFP were injected intradermally into the rat dorsum in the AAV2-VEGF or AAV2-GFP group. The saline group received saline injection. A 3 × 10 cm flap was raised in each rat two weeks post-injection. One week after surgery, flap viability was evaluated. Angiogenesis real-time PCR array was performed to analyze the expression of angiogenesis-associated genes. The AAV2-VEGF treatment significantly improved flap survival (p<0.05). Immunohistochemical staining showed increased VEGF expression in AAV2-VEGF treated flaps. The PCR array identified remarkable changes in 6 out of the 84 angiogenesis-associated genes in AAV2-VEGF treated flaps. Particularly, EGF, PDGF-A and VEGF-B genes were up-regulated in these flaps. In contrast, FGF2 gene expression was down-regulated. In conclusion, AAV2-VEGF improves flap survival and affects the expression of a series of endogenous growth factor genes, which likely play critical roles in the enhancement of ischemic flap survival. PMID:21649787

  7. Piloted simulation study of two tilt-wing flap control concepts, phase 2

    NASA Technical Reports Server (NTRS)

    Birckelbaw, Lourdes G.; Corliss, Lloyd D.; Hindson, William S.; Churchill, Gary B.

    1994-01-01

    A two phase piloted simulation study has been conducted in the Ames Vertical Motion Simulator to investigate alternative wing and flap controls for tilt-wing aircraft. This report documents the flying qualities results and findings of the second phase of the piloted simulation study and describes the simulated tilt-wing aircraft, the flap control concepts, the experiment design and the evaluation tasks. The initial phase of the study compared the flying qualities of both a conventional programmed flap and an innovative geared flap. The second phase of the study introduced an alternate method of pilot control for the geared flap and further studied the flying qualities of the programmed flap and two geared flap configurations. In general, the pilot ratings showed little variation between the programmed flap and the geared flap control concepts. Some differences between the two control concepts were noticed and are discussed in this report. The geared flap configurations had very similar results. Although the geared flap concept has the potential to reduce or eliminate the pitch control power requirements from a tail rotor or a tail thruster at low speeds and in hover, the results did not show reduced tail thruster pitch control power usage with the geared flap configurations compared to the programmed flap configuration. The addition of pitch attitude stabilization in the second phase of simulation study greatly enhanced the aircraft flying qualities compared to the first phase.

  8. Novel Biomarkers of Arterial and Venous Ischemia in Microvascular Flaps

    PubMed Central

    Nguyen, Gerard K.; Monahan, John F. W.; Davis, Gabrielle B.; Lee, Yong Suk; Ragina, Neli P.; Wang, Charles; Zhou, Zhao Y.; Hong, Young Kwon; Spivak, Ryan M.; Wong, Alex K.

    2013-01-01

    The field of reconstructive microsurgery is experiencing tremendous growth, as evidenced by recent advances in face and hand transplantation, lower limb salvage after trauma, and breast reconstruction. Common to all of these procedures is the creation of a nutrient vascular supply by microsurgical anastomosis between a single artery and vein. Complications related to occluded arterial inflow and obstructed venous outflow are not uncommon, and can result in irreversible tissue injury, necrosis, and flap loss. At times, these complications are challenging to clinically determine. Since early intervention with return to the operating room to re-establish arterial inflow or venous outflow is key to flap salvage, the accurate diagnosis of early stage complications is essential. To date, there are no biochemical markers or serum assays that can predict these complications. In this study, we utilized a rat model of flap ischemia in order to identify the transcriptional signatures of venous congestion and arterial ischemia. We found that the critical ischemia time for the superficial inferior epigastric fasciocutaneus flap was four hours and therefore performed detailed analyses at this time point. Histolgical analysis confirmed significant differences between arterial and venous ischemia. The transcriptome of ischemic, congested, and control flap tissues was deciphered by performing Affymetrix microarray analysis and verified by qRT-PCR. Principal component analysis revealed that arterial ischemia and venous congestion were characterized by distinct transcriptomes. Arterial ischemia and venous congestion was characterized by 408 and 1536>2-fold differentially expressed genes, respectively. qRT-PCR was used to identify five candidate genes Prol1, Muc1, Fcnb, Il1b, and Vcsa1 to serve as biomarkers for flap failure in both arterial ischemia and venous congestion. Our data suggests that Prol1 and Vcsa1 may be specific indicators of venous congestion and allow clinicians to

  9. Perfusion and Oxygenation of Random Advancement Skin Flaps Depend More on the Length and Thickness of the Flap Than on the Width to Length Ratio

    PubMed Central

    Memarzadeh, Khashayar; Sheikh, Rafi; Blohmé, Jonas; Torbrand, Christian

    2016-01-01

    Objective: The aim was to investigate the relationship between the dimensions (length, width, and thickness) of random advancement skin flaps and retained tissue perfusion and oxygenation. Methods: Flaps were raised on the flanks of pigs. The flaps were either 0.5 or 1.0 cm wide, thin (dissected halfway through the subcutaneous tissue) or thick (dissected down to the muscle fascia). Tissue perfusion was measured by laser Doppler velocimetry, and tissue oxygenation (pO2) was measured using a Licox system, every 0.5 cm along the flaps’ length. Tissue temperature was visualized by high-resolution infrared camera. Results: Perfusion and oxygenation decreased gradually from the base to the tip of the flap, reaching approximately 40% of presurgical values (2.0 cm) and approximately 20% (2.5 cm) from the base of the flap. There was virtually no blood flow, nor oxygen tension, 3.0 cm from the base of the flap. The width to length ratio of the flap did not determine blood flow or oxygenation, being approximately 30% in a 0.5 cm wide and 2 cm long flap, and 0% in a 1.0 cm wide and 4 cm long flap, both with a width to length ratio of 1:4. Blood flow and oxygenation were preserved to a greater extent in the thick flaps (∼40%) than in the thin flaps (∼20%), in a 0.5 cm wide and 2 cm long flap. Conclusions: The dissection of a random advancement flap results in hypoperfusion and oxygenation that cannot be predicted by the width to length ratio but depend on the length and thickness of the flap. PMID:26958105

  10. Why Do Elephants Flap Their Ears?

    NASA Astrophysics Data System (ADS)

    Koffi, Moise; Jiji, Latif; Andreopoulos, Yiannis

    2009-11-01

    It is estimated that a 4200 kg elephant generates as much as 5.12 kW of heat. How the elephant dissipates its metabolic heat and regulates its body temperature has been investigated during the past seven decades. Findings and conclusions differ sharply. The high rate of metabolic heat coupled with low surface area to volume ratio and the absence of sweat glands eliminate surface convection as the primary mechanism for heat removal. Noting that the elephant ears have high surface area to volume ratio and an extensive vascular network, ear flapping is thought to be the principal thermoregulatory mechanism. A computational and experimental program is carried out to examine flow and heat transfer characteristics. The ear is modeled as a uniformly heated oscillating rectangular plate. Our computational work involves a three-dimensional time dependent CFD code with heat transfer capabilities to obtain predictions of the flow field and surface temperature distributions. This information was used to design an experimental setup with a uniformly heated plate of size 0.2m x 0.3m oscillating at 1.6 cycles per second. Results show that surface temperature increases and reaches a steady periodic oscillation after a period of transient oscillation. The role of the vortices shed off the plate in heat transfer enhancement will be discussed.

  11. Analysis of non-symmetrical flapping airfoils

    NASA Astrophysics Data System (ADS)

    Tay, W. B.; Lim, K. B.

    2009-08-01

    Simulations have been done to assess the lift, thrust and propulsive efficiency of different types of non-symmetrical airfoils under different flapping configurations. The variables involved are reduced frequency, Strouhal number, pitch amplitude and phase angle. In order to analyze the variables more efficiently, the design of experiments using the response surface methodology is applied. Results show that both the variables and shape of the airfoil have a profound effect on the lift, thrust, and efficiency. By using non-symmetrical airfoils, average lift coefficient as high as 2.23 can be obtained. The average thrust coefficient and efficiency also reach high values of 2.53 and 0.61, respectively. The lift production is highly dependent on the airfoil’s shape while thrust production is influenced more heavily by the variables. Efficiency falls somewhere in between. Two-factor interactions are found to exist among the variables. This shows that it is not sufficient to analyze each variable individually. Vorticity diagrams are analyzed to explain the results obtained. Overall, the S1020 airfoil is able to provide relatively good efficiency and at the same time generate high thrust and lift force. These results aid in the design of a better ornithopter’s wing.

  12. ``Schooling'' of wing pairs in flapping flight

    NASA Astrophysics Data System (ADS)

    Ramananarivo, Sophie; Zhang, Jun; Ristroph, Leif; AML, Courant Collaboration; Physics NYU Collaboration

    2015-11-01

    The experimental setup implements two independent flapping wings swimming in tandem. Both are driven with the same prescribed vertical heaving motion, but the horizontal motion is free, which means that the swimmers can take up any relative position and forward speed. Experiments show however clearly coordinated motions, where the pair of wings `crystallize' into specific stable arrangements. The follower wing locks into the path of the leader, adopting its speed, and with a separation distance that takes on one of several discrete values. By systematically varying the kinematics and wing size, we show that the set of stable spacings is dictated by the wavelength of the periodic wake structure. The forces maintaining the pair cohesion are characterized by applying an external force to the follower to perturb it away from the `stable wells'. These results show that hydrodynamics alone is sufficient to induce cohesive and coordinated collective locomotion through a fluid, and we discuss the hypothesis that fish schools and bird flocks also represent stable modes of motion.

  13. Theoretical studies on flapped delta wings

    NASA Technical Reports Server (NTRS)

    Oh, S.; Tavella, D.; Roberts, L.

    1988-01-01

    The effects of leading edge flaps on the aerodynamic characteristics of a low aspect-ratio delta wing are studied theoretically. As an extension of the classical crossflow plane analysis and in order to include separated shear layers, an analogy between three dimensional steady conical and two dimensional unsteady self-similar flows is explored. This analogy provides a simple steady-unsteady relationship. The criteria for the validity of the steady-unsteady analogy are also examined. Two different theoretical techniques are used to represent the separated shear layers based on the steady-unsteady analogy, neglecting the trailing edge effect. In the first approach, each vortex system is represented by a pair of concentrated vortices connected to the separation points by straight feeding sheets. In the second approach, the vortex cloud method is adopted for simulating the flow field in the crossflow plane. The separated shear layers are replaced with a cloud of discrete vortices and the boundary element method is employed to represent the wing trace by a vorticity distribution. A simple merging scheme is used to model the core region of the vortical flow as a single vortex by imposing a restriction on the shear layer rotation angle. The results are compared with experiments and with results from 3-D panel calculations.

  14. Island medial plantar artery perforator flap for reconstruction of plantar defects.

    PubMed

    Koshima, Isao; Narushima, Mitsunaga; Mihara, Mokoto; Nakai, Ikuo; Akazawa, Satoshi; Fukuda, Norio; Watanabe, Yorikatsu; Nakagawa, Masahiro

    2007-11-01

    Three cases in which island medial plantar artery perforator flaps were successfully transferred for coverage of the plantar defects are described. This perforator flap is different from the medial plantar flap based on the medial plantar artery. The flap has no fascial component and is nourished only with the perforator of the medial plantar vessel. Therefore, transection of the medial plantar artery is usually unnecessary. This flap can cover defects on the forefoot and heel without transaction of the medial plantar system. The advantages of this flap are no need for deep or long dissection for the medial plantar vessel, no exposure of the plantar sensory nerve, a short time for flap elevation, minimal donor-site morbidity, relatively large flap survival, and no damage of both the posterior tibial and medial plantar neurovascular systems. PMID:17992152

  15. Assessment of skin flap viability using visible diffuse reflectance spectroscopy and auto-fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhu, Caigang; Chen, Shuo; Chui, Christopher Hoe-Kong; Liu, Quan

    2012-12-01

    The accurate assessment of skin flap viability is vitally important in reconstructive surgery. Early identification of vascular compromise increases the change of successful flap salvage. The ability to determine tissue viability intraoperatively is also extremely useful when the reconstructive surgeon must decide how to inset the flap and whether any tissue must be discarded. Visible diffuse reflectance and auto-fluorescence spectroscopy, which yield different sets of biochemical information, have not been used in the characterization of skin flap viability simultaneously to our best knowledge. We performed both diffuse reflectance and fluorescence measurements on a reverse MacFarlane rat dorsal skin flap model to identify the additional value of auto-fluorescence spectroscopy to the assessment of flap viability. Our result suggests that auto-fluorescence spectroscopy appears to be more sensitive to early biochemical changes in a failed flap than diffuse reflectance spectroscopy, which could be a valuable complement to diffuse reflectance spectroscopy for the assessment of flap viability.

  16. An experimental study of pressures on 60 deg Delta wings with leading edge vortex flaps

    NASA Technical Reports Server (NTRS)

    Marchman, J. F., III; Terry, J. E.; Donatelli, D. A.

    1983-01-01

    An experimental study was conducted in the Virginia Tech Stability Wind Tunnel to determine surface pressures over a 60 deg sweep delta wing with three vortex flap designs. Extensive pressure data was collected to provide a base data set for comparison with computational design codes and to allow a better understanding of the flow over vortex flaps. The results indicated that vortex flaps can be designed which will contain the leading edge vortex with no spillage onto the wing upper surface. However, the tests also showed that flaps designed without accounting for flap thickness will not be optimum and the result can be oversized flaps, early flap vortex reattachment and a second separation and vortex at the wing/flap hinge line.

  17. Does phosphodiesterase inhibition lessen facial flap necrosis in tobacco cigarette users?

    PubMed

    Pfaff, Miles; Shah, Ajul; Steinbacher, Derek

    2014-02-01

    Tobacco cigarette smoking remains a serious risk factor for necrosis of local facial skin flaps. To date, no pharmacological therapies exist for cigarette smoke-induced impairment of skin flap tissue survival. Accumulating evidence suggest that phosphodiesterase-5 (PDE-5) inhibitor therapy may counteract the negative effects of cigarette smoke on flap survival. Here, we evaluate skin flap survival in a series of consecutive tobacco cigarette users treated with the PDE-5 inhibitor, sildenafil, who underwent local flap facial reconstruction. We included 11 patients (5 females; median age: 64) with a significant smoking history. Seventeen facial flaps were performed for 14 defects. All patients received sildenafil in the postoperative setting. One complication of necrosis of the flap distal margin was encountered. Follow-up was available for all patients. Our results demonstrate that facial reconstruction in tobacco cigarette smokers can be performed with improved success and that sildenafil therapy may mitigate the deleterious effects of smoking on flap survival. PMID:24488644

  18. Pressure distribution over an NACA 23012 airfoil with a slotted and a plain flap

    NASA Technical Reports Server (NTRS)

    Wenzinger, Carl J; Delano, James B

    1938-01-01

    Report presents the results of pressure-distribution of an NACA 23012 airfoil equipped with a slotted flap and with a plain flap conducted in the 7 by 10-foot wind tunnel. A test installation was used in which the 7-foot-span airfoil was mounted vertically between the upper and lower sides of the closed test section so that two-dimensional flow was approximated. The pressures were measured on the upper and lower surfaces at one chord section both on the main airfoil and on the flaps for several different flap deflections and at several angles of attack. The data are presented in the form of pressure-distribution diagrams and as graphs of calculated section coefficients for the airfoil-and-flap combinations and also for the flaps alone. The results are useful for application to rib and flap structural design; in addition, the plain-flap data furnish considerable information applicable to the structural design of plain ailerons.

  19. Aeroacoustic performance of an externally blown flap configuration with several flap noise suppression devices

    NASA Technical Reports Server (NTRS)

    Mckinzie, D. J., Jr.

    1982-01-01

    Small scale model acoustic experiments were conducted to measure the noise produced in the flyover and sideline planes by an engine under the wing externally blown flap configuration in its approach attitude. Broadband low frequency noise reductions as large as 9 dB were produced by reducing the separation distance between the nozzle exhaust plane and the flaps. Experiments were also conducted to determine the noise suppression effectiveness in comparison with a reference configuration of three passive types of devices that were located on the jet impingement surfaces of the reference configuration. These devices produced noise reductions that varied up to 10 dB at reduced separation distances. In addition, a qualitative estimate of the noise suppression characteristics of the separate devices was made. Finally static aerodynamic performance data were obtained to evaluate the penalties incurred by these suppression devices. The test results suggest that further parametric studies are required in order to understand more fully the noise mechanisms that are affected by the suppression devices used.

  20. Morphometric study of the scapular free flap and the free rib osteomyocutaneous flap.

    PubMed

    Sönmez, Tolga Taha; Prescher, Andreas; Kanatas, Anastasios; Zaker Shahrak, Arash; Gerressen, Marcus; Knobe, Matthias; Altuntas, Selman Hakki; Modabber, Ali; Steiner, Timm Walter; Smeets, Ralf; Ghassemi, Alireza; Hölzle, Frank

    2014-04-01

    The scapula free flap is often the first choice for reconstruction of bony defects of the facial skeleton. However, the vascularised rib as part of a free rib osteomyocutaneous flap may be a suitable second choice. We have investigated the morphology and clinical dimensions of the 7th rib and the scapula, and the ability of the available bone to carry dental implants. The age and sex of the cadaver, and the donor side, were also recorded. The dimensions of the scapulas and 7th ribs (n=130 of each) from 65 cadavers were measured at 4 different points using osteometric methods. Examination showed that bone from the scapula and 7th rib were sufficient for placement of implants. The 7th rib gave reliable measurements for both height and width, and a consistent relation between compact and cancellous bone. Although the scapula provided adequate compact and cancellous bone, there were variations depending on the segment of bone chosen. Bones from male cadavers were more suitable for implantation. In both the scapula and the 7th rib ageing had a significant adverse effect in only one dimension. Most points of measurement have satisfactory bony dimensions for insertion of dental implants. PMID:24485051

  1. Maxillary reconstruction using a bipedicled osteocutaneous scapula flap.

    PubMed

    Yoshioka, I; Yamashita, Y; Khanal, A; Kodama, M; Takahashi, T; Tominaga, K

    2009-12-01

    When managing extensive maxillary defects it is difficult to provide a stable biomechanical frame for prostheses, and obturators are difficult to use. This study reviews cases involving angular branch artery pedicled scapular bone flaps (SBF) combined with or without latissimus dorsi musculocutaneous flap (LDMF). Between 2004 and 2007, four wide maxillary defects were repaired using the angular vascularized branch of the scapular bone. Tumor resection with immediate reconstruction using combined LDMF and angular artery pedicled SBF was used in 3 cases and angular artery pedicled SBF alone in 1 case. Follow up was 6 months to 2 years. Satisfactory results were obtained for facial contour, appearance, speech, deglutition and breathing. No donor site complications or restricted shoulder movements were detected. The only complication was a minor infection of one flap. This procedure is useful, functionally and aesthetically, for reconstruction of wide extensive maxillary defects as bone supplied by the angular branch has a wider arc of rotation in relation to skin flaps and has a longer pedicle length from the axillary artery, long enough to reach the maxilla. This procedure also benefits from the flexibility of the soft tissue pedicle, such as the latissimus dorsi, serratus anterior and fasciocutaneous flaps.

  2. Active Control of a Flapping Wing in a Gust Setup

    NASA Astrophysics Data System (ADS)

    Wallace, Ryan; Anderson, Mark; Glauser, Mark

    2006-11-01

    The aim of this experiment is to determine the response of a flapping Micro Air Vehicle wing to a wind gust while in forward and hovering flight and apply an active control to respond to the wind gust. The flapping wing is driven by a DC brushless motor which is geared to allow for flapping at frequencies up to 3 Hz. The wing is set up vertically in the wind tunnel, and can flap up to angles of 120 degrees. To simulate a wind gust perpendicular to the free stream flow a diffuser is set up on top of the wind tunnel. Strain gages are attached to the wing. It has been shown while simultaneously measuring the dynamical strain and the velocity field with a PIV system, that a realistic estimate of the wake flow field can obtained using low dimensional tools (POD, mLSE). The wing and the flapping mechanism are mounted directly on a force balance to calculate the lift being produced. In order to prevent flow separation on the wing during a sudden wind gust the wing is actively deformed by an attached piezoelectric actuator. The end result is to have closed loop control to produce stable hovering and forward flight.

  3. Distally Based Iliotibial Band Flap: Anatomic Study with Surgical Considerations.

    PubMed

    Wong, Victor W; Higgins, James P

    2016-09-01

    Background Reconstruction of high-risk fascia, tendon, or ligament defects may benefit from vascularized tissue. The iliotibial band (ITB), a thick fibrous tract of connective tissue, serves as a potential donor site for free tissue transfer but its blood supply has not been thoroughly investigated. The aim of this anatomical study was to investigate the vascular supply to the distal ITB and its role as a free fascial flap. Methods We dissected 16 fresh-frozen cadaveric legs and injected latex into the superolateral geniculate artery (SLGA). A distal ITB fascial flap was designed and measurements were taken for flap dimensions, pedicle length and size, and SLGA perfusion territory. Results The SLGA perfused 11.5 ± 2.3 cm of distal ITB (proximal to the lateral femoral epicondyle) and provided 6.4 ± 0.7cm of pedicle length to the ITB flap. Conclusions Chimeric options to include bone (from the lateral femoral condyle), cartilage (from the lateral femoral trochlea), muscle (from vastus lateralis or biceps femoris), and skin are possible. Surgical harvest techniques are proposed, including preservation of ITB insertions to minimize lateral knee instability. Clinical validation is needed to determine the role of the distal ITB free fascial flap in reconstructive microsurgery.

  4. [Submental island flap: a review of the literature].

    PubMed

    Bertrand, B; Foletti, J-M; Noël, W; Duron, J-B; Bardot, J

    2015-02-01

    The submental island flap is a precious tool in reconstructive surgery. It was described by Martin in 1993, inspired by platysma flaps. In our days, we can find many reliable techniques for this procedure. We reviewed the main studies of the literature that described a total of 528 patients. The rate of partial necrosis was 5.1%, complete necrosis 1.7%, and reversible lesions of the marginal mandibular branch of the facial nerve 1.1%. His versatility makes this flap appropriate for the reconstruction of every part of the face: cheeks, nose, forehead, moustache, beard, and hairs. It can also be used de-epidermised with very good results, for the reconstruction of the buccal cavity, the tongue, the roof of the mouth, the larynx, and the proximal part of the esophagus. The SMAP (Submentalis Artery Perforator flap) is an alternative flap that provides even better cosmetic results. The development of indocyanine green and infrared cameras will allow in a close future to decrease the postoperative complications.

  5. Effects of calcitriol on random skin flap survival in rats

    PubMed Central

    Zhou, Kai-liang; Zhang, Yi-hui; Lin, Ding-sheng; Tao, Xian-yao; Xu, Hua-zi

    2016-01-01

    Calcitriol, a metabolite of vitamin D, is often used in osteoporosis clinics. However, the material has other bioactivities; for example, it accelerates angiogenesis, has anti-inflammatory properties, and inhibits oxidative stress. We investigated the effects of calcitriol in a random skin flap rat model. “McFarlane flap” models were established in 84 male Sprague Dawley rats, divided into two groups. One group received intraperitoneal injections of calcitriol (2 μg/kg/day) whereas control rats received intraperitoneal injections of saline. The percentage flap survival area and tissue water content were measured 7 days later, which showed that calcitriol improved flap survival area and reduced tissue edema. It also increased the mean vessel density and upregulated levels of VEGF mRNA/protein, both of which promote flap angiogenesis. Moreover, it decreased leukocyte and macrophage infiltration, reduced the inflammatory proteins IL1β and IL6, increased SOD activity, decreased MDA content, and upregulated the level of autophagy. Overall, our results suggest that calcitriol promotes skin flap survival by accelerating angiogenesis, having anti-inflammatory effects, reducing oxidative stress, and promoting autophagy. PMID:26732750

  6. Distally Based Iliotibial Band Flap: Anatomic Study with Surgical Considerations.

    PubMed

    Wong, Victor W; Higgins, James P

    2016-09-01

    Background Reconstruction of high-risk fascia, tendon, or ligament defects may benefit from vascularized tissue. The iliotibial band (ITB), a thick fibrous tract of connective tissue, serves as a potential donor site for free tissue transfer but its blood supply has not been thoroughly investigated. The aim of this anatomical study was to investigate the vascular supply to the distal ITB and its role as a free fascial flap. Methods We dissected 16 fresh-frozen cadaveric legs and injected latex into the superolateral geniculate artery (SLGA). A distal ITB fascial flap was designed and measurements were taken for flap dimensions, pedicle length and size, and SLGA perfusion territory. Results The SLGA perfused 11.5 ± 2.3 cm of distal ITB (proximal to the lateral femoral epicondyle) and provided 6.4 ± 0.7cm of pedicle length to the ITB flap. Conclusions Chimeric options to include bone (from the lateral femoral condyle), cartilage (from the lateral femoral trochlea), muscle (from vastus lateralis or biceps femoris), and skin are possible. Surgical harvest techniques are proposed, including preservation of ITB insertions to minimize lateral knee instability. Clinical validation is needed to determine the role of the distal ITB free fascial flap in reconstructive microsurgery. PMID:27135145

  7. Total lower lip reconstruction using sensate composite radial forearm flap.

    PubMed

    Ozdemir, Ragip; Ortak, Turgut; Koçer, Uğur; Celebioğlu, Selim; Sensöz, Omer; Tiftikcioglu, Yigit Ozer

    2003-05-01

    In modern plastic and reconstructive surgery, shape and function must be considered together. These are the most important goals of any operation. There are a lot of techniques that have been reported for total lower lip reconstruction. It is believed that the radial forearm flap is the most suitable technique for lower lip and chin reconstruction after tumor excision so as to achieve better shape and functional results. The sensate radial forearm-palmaris longus free flap was used for total lower lip reconstruction in 17 patients with lower lip carcinoma with a mean age of 51 years. Two of the patients were female, and 15 were male. All the patients had squamous cell carcinoma. The patients were followed up for 1 to 3 years. Complications of these operations were partial superficial flap loss in 1 patient, partial graft loss in the donor areas of two flaps, and infection in only 1 patient. Wound dehiscence, fistula formation, suture abscesses, or sialocele was not seen in any patient. In this study, the aim was to demonstrate that the sensate radial forearm flap could produce acceptable esthetic results, good sphincteric function, and sensation in the early period after surgery. PMID:12826811

  8. Thoraco dorsal artery perforator flap for trismus release in a young girl.

    PubMed

    Deneuve, Sophie; Qassemyar, Quentin; Blancal, Jean-Philippe; Couloignier, Vincent; Sainte-Rose, Christian; Janot, François; Kolb, Frederic

    2015-11-01

    Trismus is a frequent complication occurring after treatment of tumors of the pterygomaxillary fossa. Local flaps and full-thickness skin grafts fail to release it because they usually lead to scar contracture in previously irradiated tissues. We propose to release it with a thoracodorsal artery perforator flap, which is feasible in children like other perforator flaps. It is interesting because it is thinner than the anterolateral thigh flap and its scar may be less disgraceful and easier to hide.

  9. Immediate Bilateral Breast Reconstruction with Unilateral Deep Superior Epigastric Artery and Superficial Circumflex Iliac Artery Flaps

    PubMed Central

    Hansen, Keith S.; Hartman, Brett C.; Sood, Rajiv; Socas, Juan

    2016-01-01

    Autologous breast reconstruction utilizing a perforator flap is an increasingly popular method for reducing donor site morbidity and implant-related complications. However, aberrant anatomy not readily visible on computed tomography angiography is a rare albeit real risk when undergoing perforator flap reconstruction. We present an operative case of a patient who successfully underwent a bilateral breast reconstruction sourced from a unilateral abdominal flap divided into deep superior epigastric artery and superficial circumflex iliac artery flap segments. PMID:27689054

  10. Internal-external flow integration for a thin ejector-flapped wing section

    NASA Technical Reports Server (NTRS)

    Woolard, H. W.

    1979-01-01

    Thin airfoil theories of an ejector flapped wing section are reviewed. The global matching of the external airfoil flow with the ejector internal flow and the overall ejector flapped wing section aerodynamic performance are examined. Mathematical models of the external and internal flows are presented. The delineation of the suction flow coefficient characteristics are discussed. The idealized lift performance of an ejector flapped wing relative to a jet augmented flapped wing are compared.

  11. Immediate Bilateral Breast Reconstruction with Unilateral Deep Superior Epigastric Artery and Superficial Circumflex Iliac Artery Flaps.

    PubMed

    Hansen, Keith S; Gutwein, Luke G; Hartman, Brett C; Sood, Rajiv; Socas, Juan

    2016-09-01

    Autologous breast reconstruction utilizing a perforator flap is an increasingly popular method for reducing donor site morbidity and implant-related complications. However, aberrant anatomy not readily visible on computed tomography angiography is a rare albeit real risk when undergoing perforator flap reconstruction. We present an operative case of a patient who successfully underwent a bilateral breast reconstruction sourced from a unilateral abdominal flap divided into deep superior epigastric artery and superficial circumflex iliac artery flap segments. PMID:27689054

  12. Immediate Bilateral Breast Reconstruction with Unilateral Deep Superior Epigastric Artery and Superficial Circumflex Iliac Artery Flaps

    PubMed Central

    Hansen, Keith S.; Hartman, Brett C.; Sood, Rajiv; Socas, Juan

    2016-01-01

    Autologous breast reconstruction utilizing a perforator flap is an increasingly popular method for reducing donor site morbidity and implant-related complications. However, aberrant anatomy not readily visible on computed tomography angiography is a rare albeit real risk when undergoing perforator flap reconstruction. We present an operative case of a patient who successfully underwent a bilateral breast reconstruction sourced from a unilateral abdominal flap divided into deep superior epigastric artery and superficial circumflex iliac artery flap segments.

  13. Comparison of the radial forearm flap and the thinned anterolateral thigh cutaneous flap for reconstruction of tongue defects: an evaluation of donor-site morbidity.

    PubMed

    Huang, Chih-Hung; Chen, Hung-Chi; Huang, Yau-Lin; Mardini, Samir; Feng, Guan-Ming

    2004-12-01

    The radial forearm flap is commonly used for reconstruction of tongue defects following tumor extirpation. This flap is easy to harvest and offers thin tissue with large-caliber vessels. However, its use leaves behind a conspicuous aesthetic deformity in the forearm and requires the sacrifice of a major artery of that limb, the radial artery. The anterolateral thigh cutaneous flap has found clinical applications in the reconstruction of soft-tissue defects requiring thin tissue. More recently, in a thinned form, the anterolateral thigh flap has been used for reconstructing defects of the tongue with functional results equivalent to that of the radial forearm flap. For the reconstruction of tongue defects, these two flaps could provide similar soft-tissue coverage, but they seem to result in different donor-site appearances. The donor site is closed primarily, leaving only a linear scar that is inconspicuous with normal clothing, and no functional deficit is left behind in the thigh. Thus, for the supply of flaps for tongue defects, a comparison between the radial forearm flap and the anterolateral thigh flap donor sites is provided in this study. Between December of 2000 and August of 2002, 41 patients who underwent reconstruction of defects of the tongue using either a radial forearm flap or an anterolateral thigh flap were evaluated. The focus was on the evaluation of the functional and aesthetic outcome of the donor site after harvesting these flaps for the purpose of reconstructing either total or partial tongue defects. Finally, a comparison was performed between the donor sites of the two flaps. The disadvantages of the radial forearm flap include the conspicuous unattractive scar in the forearm region, pain, numbness, and the sacrifice of a major artery of the limb. In some patients, the donor-site scar of the forearm acted as a social stigma, preventing these patients from leading a normal life. In contrast, the anterolateral thigh cutaneous flap, after

  14. A Single Amino Acid Difference between Mouse and Human 5-Lipoxygenase Activating Protein (FLAP) Explains the Speciation and Differential Pharmacology of Novel FLAP Inhibitors.

    PubMed

    Blevitt, Jonathan M; Hack, Michael D; Herman, Krystal; Chang, Leon; Keith, John M; Mirzadegan, Tara; Rao, Navin L; Lebsack, Alec D; Milla, Marcos E

    2016-06-10

    5-Lipoxygenase activating protein (FLAP) plays a critical role in the metabolism of arachidonic acid to leukotriene A4, the precursor to the potent pro-inflammatory mediators leukotriene B4 and leukotriene C4 Studies with small molecule inhibitors of FLAP have led to the discovery of a drug binding pocket on the protein surface, and several pharmaceutical companies have developed compounds and performed clinical trials. Crystallographic studies and mutational analyses have contributed to a general understanding of compound binding modes. During our own efforts, we identified two unique chemical series. One series demonstrated strong inhibition of human FLAP but differential pharmacology across species and was completely inactive in assays with mouse or rat FLAP. The other series was active across rodent FLAP, as well as human and dog FLAP. Comparison of rodent and human FLAP amino acid sequences together with an analysis of a published crystal structure led to the identification of amino acid residue 24 in the floor of the putative binding pocket as a likely candidate for the observed speciation. On that basis, we tested compounds for binding to human G24A and mouse A24G FLAP mutant variants and compared the data to that generated for wild type human and mouse FLAP. These studies confirmed that a single amino acid mutation was sufficient to reverse the speciation observed in wild type FLAP. In addition, a PK/PD method was established in canines to enable preclinical profiling of mouse-inactive compounds. PMID:27129215

  15. A Single Amino Acid Difference between Mouse and Human 5-Lipoxygenase Activating Protein (FLAP) Explains the Speciation and Differential Pharmacology of Novel FLAP Inhibitors.

    PubMed

    Blevitt, Jonathan M; Hack, Michael D; Herman, Krystal; Chang, Leon; Keith, John M; Mirzadegan, Tara; Rao, Navin L; Lebsack, Alec D; Milla, Marcos E

    2016-06-10

    5-Lipoxygenase activating protein (FLAP) plays a critical role in the metabolism of arachidonic acid to leukotriene A4, the precursor to the potent pro-inflammatory mediators leukotriene B4 and leukotriene C4 Studies with small molecule inhibitors of FLAP have led to the discovery of a drug binding pocket on the protein surface, and several pharmaceutical companies have developed compounds and performed clinical trials. Crystallographic studies and mutational analyses have contributed to a general understanding of compound binding modes. During our own efforts, we identified two unique chemical series. One series demonstrated strong inhibition of human FLAP but differential pharmacology across species and was completely inactive in assays with mouse or rat FLAP. The other series was active across rodent FLAP, as well as human and dog FLAP. Comparison of rodent and human FLAP amino acid sequences together with an analysis of a published crystal structure led to the identification of amino acid residue 24 in the floor of the putative binding pocket as a likely candidate for the observed speciation. On that basis, we tested compounds for binding to human G24A and mouse A24G FLAP mutant variants and compared the data to that generated for wild type human and mouse FLAP. These studies confirmed that a single amino acid mutation was sufficient to reverse the speciation observed in wild type FLAP. In addition, a PK/PD method was established in canines to enable preclinical profiling of mouse-inactive compounds.

  16. Surgical exploration of 71 free flaps in crisis following head and neck reconstruction.

    PubMed

    Yang, X; Li, S; Wu, K; Hu, L; Liu, W; Ji, T; Hu, Y; Xu, L; Sun, J; Zhang, Z; Zhang, C

    2016-02-01

    The medical records of patients who had undergone a free flap reconstruction after radical resection of oral cancer between January 2009 and December 2013 at the study hospital in China were reviewed retrospectively. Of the 1550 patients who underwent free flap reconstructions, 71 were explored for suspected flap compromise caused by postoperative thrombosis. Patient demographic data, clinicopathological data of the tumour, details of the free flaps, and operative findings were assessed, and the medical records were analyzed to identify the reasons for intervention and the outcomes. Of the 71 flaps in crisis, 47 (66.2%) were salvaged. Free flap failure was 6.2-times more likely to develop in patients undergoing surgical exploration after 72 h (95% confidence interval 2.090-18.197, P=0.001). Of the 19 flaps identified as subject to delayed exploration, 14 failed and three had partial necrosis. Free flap failure was 3.4-times more likely to develop in patients with perforator flaps (95% confidence interval 1.222-9.719, P=0.019). The early detection of free flap failure is critical to flap salvage. The salvage success rate decreases significantly at >72 h after the initial operation. It appears to be more difficult to salvage a perforator flap. PMID:26616026

  17. All in a Flap About Reading: Catherine Morland, Spot, and Mister Wolf.

    ERIC Educational Resources Information Center

    Smith, Vivienne

    2001-01-01

    Considers how lift-the-flap books attract very little critical attention. Attempts to redress this imbalance by suggesting that lift-the-flap books provide useful lessons in reading both literature and pictures for the young reader, that a grammar of lift-the-flap books can be postulated to facilitate their description and discussion, and that the…

  18. Surgical exploration of 71 free flaps in crisis following head and neck reconstruction.

    PubMed

    Yang, X; Li, S; Wu, K; Hu, L; Liu, W; Ji, T; Hu, Y; Xu, L; Sun, J; Zhang, Z; Zhang, C

    2016-02-01

    The medical records of patients who had undergone a free flap reconstruction after radical resection of oral cancer between January 2009 and December 2013 at the study hospital in China were reviewed retrospectively. Of the 1550 patients who underwent free flap reconstructions, 71 were explored for suspected flap compromise caused by postoperative thrombosis. Patient demographic data, clinicopathological data of the tumour, details of the free flaps, and operative findings were assessed, and the medical records were analyzed to identify the reasons for intervention and the outcomes. Of the 71 flaps in crisis, 47 (66.2%) were salvaged. Free flap failure was 6.2-times more likely to develop in patients undergoing surgical exploration after 72 h (95% confidence interval 2.090-18.197, P=0.001). Of the 19 flaps identified as subject to delayed exploration, 14 failed and three had partial necrosis. Free flap failure was 3.4-times more likely to develop in patients with perforator flaps (95% confidence interval 1.222-9.719, P=0.019). The early detection of free flap failure is critical to flap salvage. The salvage success rate decreases significantly at >72 h after the initial operation. It appears to be more difficult to salvage a perforator flap.

  19. Investigation of drag reduction through a flapping mechanism on circular cylinder

    NASA Astrophysics Data System (ADS)

    Asif, Md. Asafuddoula; Gupta, Avijit Das; Rana, M. D. Juwel; Ahmed, Dewan Hasan

    2016-07-01

    During flapping wing, a bird develops sufficient lift force as well as counteracts drag and increases its speed through different orientations of feathers on the flapping wings. Differently oriented feathers play a significant role in drag reduction during flying of a bird. With an objective to investigate the effect of installation of such flapping mechanism as a mean of drag reduction in case of flow over circular cylinder, this concept has been implemented through installation of continuous and mini flaps, made of MS sheet metal, where flaps are oriented at different angles as like feathers of flapping wings. The experiments are carried out in a subsonic wind tunnel. After validation and comparison with conventional result of drag analysis of a single cylinder, effects of flapping with Reynolds number variation, implementation of different orientations of mini flaps and variation of different interspacing distance between mini flaps are studied to find the most effective angle of attack of drag reduction on the body of circular cylinder. This research show that, installation of continuous flap reduces value of drag co-efficient, CD up to 66%, where as mini flaps are found more effective by reducing it up to 73%. Mini flaps of L/s=6.25, all angled at 30O, at the 30O angular position on the body of circular cylinder has been found the most effective angle of attack for drag reduction in case of flow over circular cylinder.

  20. Effects of hyperbaric oxygen and irradiation on experimental skin flaps in rats

    SciTech Connect

    Nemiroff, P.M.; Merwin, G.E.; Brant, T.; Cassisi, N.J.

    1985-08-01

    This study investigated the effects of hyperbaric oxygen (HBO) and irradiation (RT) on experimental skin flaps in rats under varying conditions. Animals were assigned at random to 1 of 15 groups that represented all possible ordering effects of HBO, RT, and flap, as well as controls that included flap-only, RT-only, and HBO-only groups. Cranially based skin flaps measuring 3 x 9 cm were elevated on the dorsum. The surviving length was evaluated with fluorescein dye 7 days after the operation. Depending on the treatment condition, HBO was given either 48 hours or 24 hours before flap elevation, or within 4 hours or 48 hours after flap elevation. Rats receiving RT (WCo) were given a single dose of 1000 rads to the dorsum. Results showed that all groups receiving HBO within 4 hours after flap elevation had significantly greater flap survival length, with as much as a 22% greater length of surviving flap. HBO given 48 hours before flap elevation also significantly improved flap survival over controls. RT appeared to have no immediate significant effect on flap survival. However, rats receiving RT, regardless of other factors, gained significantly less weight than did controls. Findings clearly indicate that, to be effective, HBO needs to be given as soon after surgery as possible.

  1. Physiological, aerodynamic and geometric constraints of flapping account for bird gaits, and bounding and flap-gliding flight strategies.

    PubMed

    Usherwood, James Richard

    2016-11-01

    Aerodynamically economical flight is steady and level. The high-amplitude flapping and bounding flight style of many small birds departs considerably from any aerodynamic or purely mechanical optimum. Further, many large birds adopt a flap-glide flight style in cruising flight which is not consistent with purely aerodynamic economy. Here, an account is made for such strategies by noting a well-described, general, physiological cost parameter of muscle: the cost of activation. Small birds, with brief downstrokes, experience disproportionately high costs due to muscle activation for power during contraction as opposed to work. Bounding flight may be an adaptation to modulate mean aerodynamic force production in response to (1) physiological pressure to extend the duration of downstroke to reduce power demands during contraction; (2) the prevention of a low-speed downstroke due to the geometric constraints of producing thrust; (3) an aerodynamic cost to flapping with very low lift coefficients. In contrast, flap-gliding birds, which tend to be larger, adopt a strategy that reduces the physiological cost of work due both to activation and contraction efficiency. Flap-gliding allows, despite constraints to modulation of aerodynamic force lever-arm, (1) adoption of moderately large wing-stroke amplitudes to achieve suitable muscle strains, thereby reducing the activation costs for work; (2) reasonably quick downstrokes, enabling muscle contraction at efficient velocities, while being (3) prevented from very slow weight-supporting upstrokes due to the cost of performing 'negative' muscle work.

  2. Physiological, aerodynamic and geometric constraints of flapping account for bird gaits, and bounding and flap-gliding flight strategies.

    PubMed

    Usherwood, James Richard

    2016-11-01

    Aerodynamically economical flight is steady and level. The high-amplitude flapping and bounding flight style of many small birds departs considerably from any aerodynamic or purely mechanical optimum. Further, many large birds adopt a flap-glide flight style in cruising flight which is not consistent with purely aerodynamic economy. Here, an account is made for such strategies by noting a well-described, general, physiological cost parameter of muscle: the cost of activation. Small birds, with brief downstrokes, experience disproportionately high costs due to muscle activation for power during contraction as opposed to work. Bounding flight may be an adaptation to modulate mean aerodynamic force production in response to (1) physiological pressure to extend the duration of downstroke to reduce power demands during contraction; (2) the prevention of a low-speed downstroke due to the geometric constraints of producing thrust; (3) an aerodynamic cost to flapping with very low lift coefficients. In contrast, flap-gliding birds, which tend to be larger, adopt a strategy that reduces the physiological cost of work due both to activation and contraction efficiency. Flap-gliding allows, despite constraints to modulation of aerodynamic force lever-arm, (1) adoption of moderately large wing-stroke amplitudes to achieve suitable muscle strains, thereby reducing the activation costs for work; (2) reasonably quick downstrokes, enabling muscle contraction at efficient velocities, while being (3) prevented from very slow weight-supporting upstrokes due to the cost of performing 'negative' muscle work. PMID:27418386

  3. Video measurements of instantaneous forces of flapping wing vehicles

    NASA Astrophysics Data System (ADS)

    Jennings, Alan; Mayhew, Michael; Black, Jonathan

    2015-12-01

    Flapping wings for small aerial vehicles have revolutionary potential for maneuverability and endurance. Ornithopters fail to achieve the performance of their biological equivalents, despite extensive research on how animals fly. Flapping wings produce peak forces due to the stroke reversal of the wing. This research demonstrates in-flight measurements of an ornithopter through the use of image processing, specifically measuring instantaneous forces. Results show that the oscillation about the flight path is significant, being about 20% of the mean velocity and up to 10 g's. Results match forces with deformations of the wing to contrast the timing and wing shape of the upstroke and the downstroke. Holding the vehicle fixed (e.g. wind tunnel testing or simulations) structural resonance is affected along with peak forces, also affecting lift. Non-contact, in-flight measurements are proposed as the best method for matching the flight conditions of flapping wing vehicles.

  4. Efficient flapping flight using flexible wings oscillating at resonance

    NASA Astrophysics Data System (ADS)

    Alexeev, Alexander; Masoud, Hassan

    2010-11-01

    Using a fully-coupled computational approach that integrates the lattice Boltzmann and lattice spring models, we investigate the three-dimensional aerodynamics of flexible flapping wings at resonance. The wings are tilted from the horizontal and oscillate vertically driven by a force applied at the wing root. Our simulations reveal that resonance oscillations drastically enhance the aerodynamic efficiency of low-Reynolds-number plunging, and yield lift and lift-to-weight ratio comparable to the values typical for small insects. Within the resonance band, we identify two flapping regimes leading to the maximum lift and the maximum efficiency, which are characterized by different bending modes of flexible flapping wings. Our results indicate the feasibility of using flexible wings driven by a simple harmonic stroke for designing efficient microscale flying machines.

  5. Two staged modified substitution urethroplasty using appendix-free flap.

    PubMed

    Hiradfar, Mehran; Shojaeian, Reza; Sharifabad, Parisa Saeedi

    2015-01-01

    Reconstruction of long posterior urethra defect is technically challenging. Substitution urethroplasty is used in long, complex, recurrent posterior urethral strictures. This article presents a modified technique and the clinical outcome of two-stage substitution urethroplasty with appendix free flap and microvascular anastomosis. A three-year-old boy with a 5 cm iatrogenic posterior urethral defect was managed by urethral substitution using the appendix. An appendix-free flap was used according to anatomic limitations, employing the transposed inferior epigastric artery and saphenous vein to maintain conduit blood supply. The conduit was buried in the scrotum for 3 weeks and its viability monitored until the final reconstructive stage. Two-year follow-up with ultrasound and cystoscopy revealed satisfactory results. A well-vascularised bed and flap are the mainstays of substitution urethroplasty, so we suggest inferior epigastric artery perineal transposition and staged reconstruction as alternatives that may improve the blood supply of the neourethra.

  6. Treatment of temporomandibular joint ankylosis with temporalis superficial fascia flap.

    PubMed

    Karasu, Hakan Alpay; Okcu, Kemal Murat; Ortakoglu, Kerim; Bayar, Gurkan Rasit; Aydintug, Yavuz Sinan

    2005-02-01

    Temporomandibular joint (TMJ) ankylosis is characterized by the formation of bony or fibrous mass, which replaces the normal articulation and limitation of mouth opening. This study aims to determine the efficacy of arthroplasty and interpositional fascia flap in the treatment of unilateral and bilateral TMJ ankylosis in three young adult men. Our operative protocol for unilateral and bilateral TMJ ankylosis entailed resection of ankylotic mass, intraoral ipsilateral and bilateral arthroplasty, interpositional tissue transfer to the TMJ with temporalis superficial fascia flap, maxillomandibular fixation, and early mobilization and aggressive physiotherapy. Early postoperative initial exercise, physiotherapy, and strict follow-up play an important role in preventing postoperative adhesions. The temporalis superficial facia flap is an autogenous graft that has the advantages of close proximity to the TMJ minimal surgical morbidity, and successful clinical results. It was found to be a valuable option for TMJ ankylosis reconstruction. PMID:15782841

  7. Flapping dynamics of a flexible propulsor near ground

    NASA Astrophysics Data System (ADS)

    Ryu, Jaeha; Park, Sung Goon; Kim, Boyoung; Sung, Hyung Jin

    2016-06-01

    The flapping motion of a flexible propulsor near the ground was simulated using the immersed boundary method. The hydrodynamic benefits of the propulsor near the ground were explored by varying the heaving frequency (St) of the leading edge of the flexible propulsor. Propulsion near the ground had some advantages in generating thrust and propelling faster than propulsion away from the ground. The mode analysis and flapping amplitude along the Lagrangian coordinate were examined to analyze the kinematics as a function of the ground proximity (d) and St. The trailing edge amplitude (a_tail ) and the net thrust (overline{{F}}_x ) were influenced by St of the flexible propulsor. The vortical structures in the wake were analyzed for different flapping conditions.

  8. Acute effects of cigarette smoke exposure on experimental skin flaps

    SciTech Connect

    Nolan, J.; Jenkins, R.A.; Kurihara, K.; Schultz, R.C.

    1985-04-01

    Random vascular patterned caudally based McFarlane-type skin flaps were elevated in groups of Fischer 344 rats. Groups of rats were then acutely exposed on an intermittent basis to smoke generated from well-characterized research filter cigarettes. Previously developed smoke inhalation exposure protocols were employed using a Maddox-ORNL inhalation exposure system. Rats that continued smoke exposure following surgery showed a significantly greater mean percent area of flap necrosis compared with sham-exposed groups or control groups not exposed. The possible pathogenesis of this observation as well as considerations and correlations with chronic human smokers are discussed. Increased risks of flap necrosis by smoking in the perioperative period are suggested by this study.

  9. Detached Eddy Simulation of Flap Side-Edge Flow

    NASA Technical Reports Server (NTRS)

    Balakrishnan, Shankar K.; Shariff, Karim R.

    2016-01-01

    Detached Eddy Simulation (DES) of flap side-edge flow was performed with a wing and half-span flap configuration used in previous experimental and numerical studies. The focus of the study is the unsteady flow features responsible for the production of far-field noise. The simulation was performed at a Reynolds number (based on the main wing chord) of 3.7 million. Reynolds Averaged Navier-Stokes (RANS) simulations were performed as a precursor to the DES. The results of these precursor simulations match previous experimental and RANS results closely. Although the present DES simulations have not reached statistical stationary yet, some unsteady features of the developing flap side-edge flowfield are presented. In the final paper it is expected that statistically stationary results will be presented including comparisons of surface pressure spectra with experimental data.

  10. Aircraft wake-vortex minimization by use of flaps

    NASA Technical Reports Server (NTRS)

    Corsiglia, V. R.; Dunham, R. E., Jr.

    1977-01-01

    A survey was made of research on the alleviation of the trailing vortex hazard by altering span loading with flaps on the generator airplane. Flap configurations of the generator that shed multiple vortices were found to have wakes that dispersed by vortex merging and sinusoidal instability. Reductions of approximately 50 percent in both the wake rolling moment imposed on a following aircraft and the aircraft separation requirement were achieved in the ground based and flight test experiments by deflecting the trailing edge flaps more inboard than outboard. Significantly, this configuration did not increase the drag or vibration on the generating aircraft compared to the conventional landing configuration. Ground based results of rolling moment measurement and flow visualization are shown, using a water tow facility, an air tow facility, and a wind tunnel. Flight test results are also shown, using a full scale B-747 airplane. General agreement was found among the results of the various ground based facilities and the flight tests.

  11. Flap Side-Edge Noise: Acoustic Analysis of Sen's Model

    NASA Technical Reports Server (NTRS)

    Hardin, Jay C.; Martin, James E.

    1996-01-01

    The two-dimensional flap side-edge flow model developed by Sen is analyzed to reveal the noise production potential of the proposed mechanism. The model assumes that a vortex will form at the equilibrium position off the side edge of the flap. The vortex is then perturbed away from the equilibrium position by incoming turbulence causing it to oscillate and thus radiate sound. The noise field is calculated three-dimensionally by taking the flap to have a finite chord. Spectra and directivity of the farfield sound are presented. In addition, the effect of retarded time differences is evaluated. The parameters in the model are related to typical aircraft parameters and noise reduction possibilities are proposed.

  12. Finite element analysis of aeroacoustic jet-flap flows

    NASA Technical Reports Server (NTRS)

    Baker, A. J.; Manhardt, P. D.

    1977-01-01

    A computational analysis was performed on the steady, turbulent aerodynamic flowfields associated with a jet-blown flap. For regions devoid of flow separation, a parabolic approximation to the governing time-averaged Navier-Stokes equations was applied. Numerical results are presented for the symmetry plane flow of a slot-nozzle planar jet flap geometry, including prediction of flowfield evolution within the secondary mixing region immediately downstream of the trailing edge. Using a two equation turbulence kinetic energy closure model, rapid generation and decay of large spatial gradients in mean and correlated fluctuating velocity components within the immediate wake region were predicted. Modifications to the turbulent flow structure, as induced by porous surface treatment of the flap, were evaluated. The recirculating flow within a representative discrete slot in the surface was evaluated, using the two dimensional, time-averaged Navier-Stokes equations.

  13. Latissimus Dorsi Flap Invasion by Ductal Breast Carcinoma after Lipofilling

    PubMed Central

    Alharbi, Muhannad; Garrido, Ignacio; Vaysse, Charlotte; Chavoin, Jean Pierre; Grolleau, Jean Louis

    2013-01-01

    Summary: Autologous fat grafting is commonly performed in reconstructive breast surgery but also increasingly in breast augmentation surgery. On the international level, we are witnessing an important increased confidence for this procedure. Nevertheless, it continues to raise questions on the risks of cancer. A 66-year-old patient benefited from a lipofilling to improve a latissimus dorsi flap breast reconstruction, 7 years after initial cancer management. Two years later, constant pain in the flap leads to reoperation. The flap showed a major retraction with histologically massive infiltration of the muscle by an undifferentiated carcinoma of breast origin. The tumor cells were displayed directly in contact with lipofilling inside the muscle. Without establishing any causal link between these 2 events, this case raises the question once more of the risks of breast cancer and encourages us to continue being careful. PMID:25289263

  14. Passive Porous Treatment for Reducing Flap Side-Edge Noise

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan M.; Khorrami, Mehdi R.

    2008-01-01

    A passive porous treatment has been proposed as a means of suppressing noise generated by the airflow around the side edges of partial-span flaps on airplane wings when the flaps are extended in a high-lift configuration. The treatment proposed here does not incur any aerodynamic penalties and could easily be retrofit to existing airplanes. The treatment could also be applied to reduce noise generated by turbomachinery, including wind turbines. Innovative aspects of the proposed treatment include a minimum treatment area and physics-based procedure for treatment design. The efficacy of the treatment was confirmed during wind-tunnel experiments at NASA Ames, wherein the porous treatment was applied to a minute surface area in the vicinity of a flap edge on a 26-percent model of Boeing 777-200 wing.

  15. An Experimental Investigation on Flapping Flexible Membrane Wings

    NASA Astrophysics Data System (ADS)

    Hu, Hui; Abate, Gregg; Albertani, Roberto

    2008-11-01

    Thin and flexible membrane wings are unique to flying and gliding mammals, such as bats, flying squirrels and sugar gliders. These animals exhibit extraordinary flight capabilities with respect to maneuvering and agility that are not observed in other species of comparable size. In this study, comprehensive wind tunnel experiments are conducted to assess the effects of membrane flexibility (rigidity) on the aerodynamic performance of the flapping flexible membrane wings to quantify the benefits of using flexible membrane wings compared with conventional rigid wings for flapping-wing Micro-Air-Vehicle (MAV) applications. The present study is conducted from the viewpoint of aerospace engineers to try to leverage the unique feature of flexible membrane airfoils/wings found in bats and other flying/gliding mammals as an effective aerodynamic control method to explore the potential applications of such non-traditional, bio-inspired flexible membrane wings to flapping-wing MAVs to improve their flight agility and maneuverability.

  16. Chord-wise Tip Actuation on Flexible Flapping Plates

    NASA Astrophysics Data System (ADS)

    Martin, Nathan; Gharib, Morteza

    2015-11-01

    The aerodynamic characteristics of low aspect ratio flapping plates are strongly influenced by the interaction between tip and edge vortices. This has led to the development of tip actuation mechanisms which bend the tip towards the root of the plate in the span-wise direction during oscillation to investigate its impact. In our current work, a tip actuation mechanism to bend a flat plate's two free corners towards one another in the chord-wise direction is developed using a shape memory alloy. The aerodynamic forces and resulting flow field are investigated from dynamically altering the tip chord-wise curvature while flapping. The frequency of oscillation, stroke angle, flexibility, and tip actuation timing are independently varied to determine their individual effects. These results will further the fundamental understanding of flapping wing aerodynamics. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE 1144469.

  17. T-FLAP improvement for VOS Program

    NASA Astrophysics Data System (ADS)

    Marcelli, Marco; Piermattei, Viviana; Madonia, Alice; Mainardi, Umberto; Manzella, Giuseppe M. R.

    2010-05-01

    The operational oceanography has been engaged in the development of new acquisition, transmission and assimilation systems in order to have the widest possible coverage of real time informations, reflecting the guidelines of the World Meteorological Organization (WMO) and of the Intergovernmental Oceanographic Commission (IOC). Physical and biological processes of marine ecosystems have a high spatial and temporal variability, whose study is possible only through high resolution and synoptic observations. More than for the physical variables, the biological ones have to be observed in situ. Especially in the mid-high latitudes, a deep observation of the water column is needed, because of the typical distribution of phytoplankton's biomass (Mann and Lazier, 1991). In the last times an extensive use of XBT was performed in order to provide near real time analysis of the ocean temperature, but there is still a lack in the biomass estimation. T-FLAP technology (Temperature and Fluorescence LAunchable Probe - Marcelli et al. 2007) was designed to answer to the claim of a cost effective temperature and fluorescence autonomous probe, to be used on ships of opportunity for the Voluntary Observing Ship Program (VOS). During the last three years the probe was upgraded and improved both in materials and in measure sensitivity. New LEDs were mounted to increase the radiant power of the excitation source.. In order to evaluate the red filter efficiency to detect fluorescence chlorophyll a emission wavelengths, transmittance of new available filters in the range 682-685 nm was calculated. In vivo fluorescence spectra of each filter were also performed on samples from Chlorella sp. cultures, to assess the percentage of the fluorescence emission peak transmitted by the filters. A multiple system was designed and realized for a high accuracy dynamic calibration of the probes.

  18. Reconstruction of Female Urethra with Tubularized Anterior Vaginal Flap

    PubMed Central

    Sawant, Ajit; Kumar, Vikash; Pawar, Prakash; Tamhankar, Ashwin; Bansal, Sumit; Kapadnis, Lomesh; Savalia, Abhishek

    2016-01-01

    Introduction Female urethral injury is a rare disease. Causes of urethral injuries are prolonged obstructed labour, gynaecological surgeries like vaginoplasty and post traumatic urethral injuries. The present study was conducted to evaluate outcome of female urethral reconstruction using tubularized anterior vaginal wall flap covered with fibroadipose martius flap and autologous fascia sling in patients with urethral loss. Aim Aim of study was to evaluate outcome of reconstruction of female urethra with tubularized anterior vaginal flap. Materials and Methods Retrospective analysis of all the patients with complete urethral loss was done from August 2008 to July 2015. Total seven patients were included in study. All patients presenting with total urethral loss were included. These patients were treated with tubularized anterior vaginal flap. Neourethra was covered with Martius labial flap and autologous fascia lata or rectus abdominis fascia sling. Most common cause of urethral loss was obstructed labour (57.1%). Postoperatively patients were assessed for continence, urine flow rate, ultrasound for upper urinary tract and post void residue. Results Mean operative time was 180 minutes (160-200 minutes) and Intraoperative blood loss was 220ml (170-260 ml). Mean postoperative hospital stay was eight days (seven to nine days) Mean post surgery maximum urine flow rate was more than 15ml/sec (6.7-18.2ml/sec) and mean post void residual urine was 22.5ml (10-50ml). Median follow-up time was 35 months. All patients were catheter free and continent post three weeks of surgery except one patient who developed mild stress urinary incontinence. One patient developed urethral stenosis which was managed by intermittent serial urethral dilatation. Conclusion Female neourethral reconstruction with tabularized anterior vaginal flap and autologous pubovaginal sling is feasible in patients of total urethral loss with success rate of approximately 86%. It should be considered in

  19. Reconstruction of Female Urethra with Tubularized Anterior Vaginal Flap

    PubMed Central

    Sawant, Ajit; Kumar, Vikash; Pawar, Prakash; Tamhankar, Ashwin; Bansal, Sumit; Kapadnis, Lomesh; Savalia, Abhishek

    2016-01-01

    Introduction Female urethral injury is a rare disease. Causes of urethral injuries are prolonged obstructed labour, gynaecological surgeries like vaginoplasty and post traumatic urethral injuries. The present study was conducted to evaluate outcome of female urethral reconstruction using tubularized anterior vaginal wall flap covered with fibroadipose martius flap and autologous fascia sling in patients with urethral loss. Aim Aim of study was to evaluate outcome of reconstruction of female urethra with tubularized anterior vaginal flap. Materials and Methods Retrospective analysis of all the patients with complete urethral loss was done from August 2008 to July 2015. Total seven patients were included in study. All patients presenting with total urethral loss were included. These patients were treated with tubularized anterior vaginal flap. Neourethra was covered with Martius labial flap and autologous fascia lata or rectus abdominis fascia sling. Most common cause of urethral loss was obstructed labour (57.1%). Postoperatively patients were assessed for continence, urine flow rate, ultrasound for upper urinary tract and post void residue. Results Mean operative time was 180 minutes (160-200 minutes) and Intraoperative blood loss was 220ml (170-260 ml). Mean postoperative hospital stay was eight days (seven to nine days) Mean post surgery maximum urine flow rate was more than 15ml/sec (6.7-18.2ml/sec) and mean post void residual urine was 22.5ml (10-50ml). Median follow-up time was 35 months. All patients were catheter free and continent post three weeks of surgery except one patient who developed mild stress urinary incontinence. One patient developed urethral stenosis which was managed by intermittent serial urethral dilatation. Conclusion Female neourethral reconstruction with tabularized anterior vaginal flap and autologous pubovaginal sling is feasible in patients of total urethral loss with success rate of approximately 86%. It should be considered in

  20. Recent progress in flapping wing aerodynamics and aeroelasticity

    NASA Astrophysics Data System (ADS)

    Shyy, W.; Aono, H.; Chimakurthi, S. K.; Trizila, P.; Kang, C.-K.; Cesnik, C. E. S.; Liu, H.

    2010-10-01

    Micro air vehicles (MAVs) have the potential to revolutionize our sensing and information gathering capabilities in areas such as environmental monitoring and homeland security. Flapping wings with suitable wing kinematics, wing shapes, and flexible structures can enhance lift as well as thrust by exploiting large-scale vortical flow structures under various conditions. However, the scaling invariance of both fluid dynamics and structural dynamics as the size changes is fundamentally difficult. The focus of this review is to assess the recent progress in flapping wing aerodynamics and aeroelasticity. It is realized that a variation of the Reynolds number (wing sizing, flapping frequency, etc.) leads to a change in the leading edge vortex (LEV) and spanwise flow structures, which impacts the aerodynamic force generation. While in classical stationary wing theory, the tip vortices (TiVs) are seen as wasted energy, in flapping flight, they can interact with the LEV to enhance lift without increasing the power requirements. Surrogate modeling techniques can assess the aerodynamic outcomes between two- and three-dimensional wing. The combined effect of the TiVs, the LEV, and jet can improve the aerodynamics of a flapping wing. Regarding aeroelasticity, chordwise flexibility in the forward flight can substantially adjust the projected area normal to the flight trajectory via shape deformation, hence redistributing thrust and lift. Spanwise flexibility in the forward flight creates shape deformation from the wing root to the wing tip resulting in varied phase shift and effective angle of attack distribution along the wing span. Numerous open issues in flapping wing aerodynamics are highlighted.

  1. Scalp Rotation Flap for Reconstruction of Complex Soft Tissue Defects.

    PubMed

    Costa, Dary J; Walen, Scott; Varvares, Mark; Walker, Ronald

    2016-02-01

    Importance Scalp reconstructions may be required after tumor resection or trauma. The inherent anatomy of the scalp presents challenges and may limit reconstructive options. Objective To describe and investigate the scalp rotation flap as a reconstructive technique for complex soft tissue defects. Design Retrospective case series with a mean follow-up of 13 months. Setting Tertiary academic center. Participants A total of 22 patients with large scalp soft tissue defects undergoing scalp rotation flap reconstruction. Interventions The flap is designed adjacent to the defect and elevated in the subgaleal plane. The flap is rotated into the defect, and a split-thickness skin graft is placed over the donor site periosteum. Main Outcomes and Measure Data points collected included defect size, operative time, hospital stay, and patient satisfaction with cosmetic outcome. Results Mean patient age was 71 years. Mean American Society of Anesthesiologist classification was 2.8. Mean defect size was 41 cm(2) (range: 7.8-120 cm(2)), and 19 of 22 defects resulted from a neoplasm resection. Mean operative time was 181 minutes, and mean hospital stay was 2.4 days. There were no intraoperative complications. Three patients with previous radiation therapy had distal flap necrosis. Twenty-one patients (95%) reported an acceptable cosmetic result. Conclusions and Relevance The scalp rotation flap is an efficient and reliable option for reconstructing complex soft tissue defects. This can be particularly important in patients with significant medical comorbidities who cannot tolerate a lengthy operative procedure. PMID:26949586

  2. Scalp Rotation Flap for Reconstruction of Complex Soft Tissue Defects.

    PubMed

    Costa, Dary J; Walen, Scott; Varvares, Mark; Walker, Ronald

    2016-02-01

    Importance Scalp reconstructions may be required after tumor resection or trauma. The inherent anatomy of the scalp presents challenges and may limit reconstructive options. Objective To describe and investigate the scalp rotation flap as a reconstructive technique for complex soft tissue defects. Design Retrospective case series with a mean follow-up of 13 months. Setting Tertiary academic center. Participants A total of 22 patients with large scalp soft tissue defects undergoing scalp rotation flap reconstruction. Interventions The flap is designed adjacent to the defect and elevated in the subgaleal plane. The flap is rotated into the defect, and a split-thickness skin graft is placed over the donor site periosteum. Main Outcomes and Measure Data points collected included defect size, operative time, hospital stay, and patient satisfaction with cosmetic outcome. Results Mean patient age was 71 years. Mean American Society of Anesthesiologist classification was 2.8. Mean defect size was 41 cm(2) (range: 7.8-120 cm(2)), and 19 of 22 defects resulted from a neoplasm resection. Mean operative time was 181 minutes, and mean hospital stay was 2.4 days. There were no intraoperative complications. Three patients with previous radiation therapy had distal flap necrosis. Twenty-one patients (95%) reported an acceptable cosmetic result. Conclusions and Relevance The scalp rotation flap is an efficient and reliable option for reconstructing complex soft tissue defects. This can be particularly important in patients with significant medical comorbidities who cannot tolerate a lengthy operative procedure.

  3. Aeroelastic Airworthiness Assesment of the Adaptive Compliant Trailing Edge Flaps

    NASA Technical Reports Server (NTRS)

    Herrera, Claudia Y.; Spivey, Natalie D.; Lung, Shun-fat; Ervin, Gregory; Flick, Peter

    2015-01-01

    The Adaptive Compliant Trailing Edge (ACTE) demonstrator is a joint task under the National Aeronautics and Space Administration Environmentally Responsible Aviation Project in partnership with the Air Force Research Laboratory and FlexSys, Inc. (Ann Arbor, Michigan). The project goal is to develop advanced technologies that enable environmentally friendly aircraft, such as adaptive compliant technologies. The ACTE demonstrator flight-test program encompassed replacing the Fowler flaps on the SubsoniC Aircraft Testbed, a modified Gulfstream III (Gulfstream Aerospace, Savannah, Georgia) aircraft, with control surfaces developed by FlexSys. The control surfaces developed by FlexSys are a pair of uniquely-designed unconventional flaps to be used as lifting surfaces during flight-testing to validate their structural effectiveness. The unconventional flaps required a multidisciplinary airworthiness assessment to prove they could withstand the prescribed flight envelope. Several challenges were posed due to the large deflections experienced by the structure, requiring non-linear analysis methods. The aeroelastic assessment necessitated both conventional and extensive testing and analysis methods. A series of ground vibration tests (GVTs) were conducted to provide modal characteristics to validate and update finite element models (FEMs) used for the flutter analyses for a subset of the various flight configurations. Numerous FEMs were developed using data from FlexSys and the ground tests. The flap FEMs were then attached to the aircraft model to generate a combined FEM that could be analyzed for aeroelastic instabilities. The aeroelastic analysis results showed the combined system of aircraft and flaps were predicted to have the required flutter margin to successfully demonstrate the adaptive compliant technology. This paper documents the details of the aeroelastic airworthiness assessment described, including the ground testing and analyses, and subsequent flight

  4. Periosteal Pedicle Flap Harvested during Vestibular Extension for Root Coverage.

    PubMed

    Kumar, Shubham; Gupta, Krishna Kumar; Agrawal, Rahul; Srivastava, Pratima; Soni, Shalabh

    2015-01-01

    Root exposure along with inadequate vestibular depth is a common clinical finding. Treatment option includes many techniques to treat such defects for obtaining predictable root coverage. Normally, the vestibular depth is increased first followed by a second surgery for root coverage. The present case report describes a single-stage technique for vestibular extension and root coverage in a single tooth by using the Periosteal Pedicle Flap (PPF). This technique involves no donor site morbidity and allows for reflection of sufficient amount of periosteal flap tissue with its own blood supply at the surgical site, thus increasing the chances of success of root coverage with simultaneous increase in vestibular depth. PMID:26788377

  5. Experimental study of flapping jets in a soap film

    NASA Astrophysics Data System (ADS)

    Lee, Julia; Kim, Ildoo; Mandre, Shreyas

    2015-11-01

    Plateau and Rayleigh's observation and explanation on jet instability have inspired us over the years and there has been a significant advance in understanding the jet dynamics. Here, we present a quasi-two-dimensional experimental study of flapping jets in a soap film. Newtonian and non-Newtonian solutions are injected in a flowing soap film. Thinning, break-ups, and beads-on-a-string of the jets, and axisymmetric vortices shredded from the flapping jets are visualized. We employ PIV of the flow motion around the jets to gain an understanding of the roles of instabilities in the flow.

  6. Deep digital burns treated with 2 abdominal flaps: case report.

    PubMed

    Wu, Choulang; Zhou, Lichun; Zhu, Lili; Zheng, Jinman

    2013-11-01

    We present the case of a 22-year-old man with third- to fourth-degree flame burns to all fingers of the right hand. After removing the necrotic tissues and amputating the carbonized distal segments of each finger, we covered the injured thumb with a paraumbilical tubular flap and covered the other fingers with an abdominal wall marsupial flap. Fifty days after injury, all the wounds healed, and the remaining fingers were salvaged. Four months after injury, the grip strength and the first web span of the right hand was 23.6 kg and 53°, and the patient could fulfill almost all the activities of daily living.

  7. Hand Allograft Saved by an Ultrathin Groin Flap

    PubMed Central

    Château, Joseph; Gazarian, Aram; Boucher, Fabien; Badet, Lionel; Braye, Fabienne; Saint-Cyr, Michel

    2016-01-01

    Summary: We report a case of a young double-hand allotransplant patient who presented with a full-thickness skin necrosis of the dorsum of the left hand after vascular compromise of the allotransplantation. Considering the lack of viable dorsal tissue overlying the extensor tendons and the need for early hand rehabilitation, an ultrathin pedicled groin flap was used for the coverage. This procedure resulted in salvaging the allotransplantation, and the patient was able to successfully return to work after his surgery. To our knowledge, this is the only case of an upper extremity allotransplant salvaged by a pedicled flap. PMID:27757334

  8. Nasolabial Flap in Maxillofacial Gunshot Trauma: A Case Series

    PubMed Central

    Rahpeyma, Amin; Khajehahmadi, Saeedeh

    2016-01-01

    Introduction The nasolabial flap (NLF) has many advantages in oromaxillary reconstruction, but the majority of cases are reconstructions after pathologic resections. Its usage in trauma surgery, especially in the management of gunshot wounds, is rarely mentioned. Case Presentation Three cases involving gunshot injuries to the face are presented: one for reconstruction of the nasal ala, another for bone graft coverage in mandibular reconstruction, and the third for the repair of premaxillary hard and soft tissue avulsive defects. Conclusions The NLF is a thin, pliable flap and is useful for intraoral and facial reconstruction of trauma patients with small to moderate soft tissue loss. PMID:27148497

  9. The Modified 3-square Flap Method for Reconstruction of Toe Syndactyly.

    PubMed

    Iida, Naoshige; Watanabe, Ayako

    2016-07-01

    Bandoh reported the 3-square-flap method as a procedure for interdigital space reconstruction in patients with minor syndactyly. We recently modified this flap design so that it could be used in the treatment of toe syndactyly involving fusion of the areas distal to the proximal interphalangeal joint. With our method, the reconstructed interdigital space consists of 4 oblong flaps (A through D). Flaps A and D are designed on the dorsal side, flap B is designed on the frontal plane of the interdigital space, and flap C is designed on the plantar side. Flaps A, B, and C are raised immediately below the dermis in a manner that allowed slight fat tissue to adhere to each flap. Flap D is freed to a degree minimally needed for dislocation, while leaving a thick subcutaneous pedicle. Flaps A, B, and C are each folded in 90 degrees; flap D is dislocated to the proximal plane of the reconstructed digit, followed by skin suturing. In this process, suturing is avoided between flaps A and C, between flaps A and D, and between flaps B and D. During the period of 2011 to 2015, we treated 8 patients of toe syndactyly involving fusion distal to the proximal interphalangeal joint. Cases of congenital syndactyly received surgery between the ages of 8 and 11 months. Using this technique, flap ischemia/necrosis was not observed. During the postoperative follow-up period, the interdigital space retained sufficient depth without developing any scar contracture. No case required additional surgery. PMID:27536472

  10. The Modified 3-square Flap Method for Reconstruction of Toe Syndactyly

    PubMed Central

    Watanabe, Ayako

    2016-01-01

    Bandoh reported the 3-square-flap method as a procedure for interdigital space reconstruction in patients with minor syndactyly. We recently modified this flap design so that it could be used in the treatment of toe syndactyly involving fusion of the areas distal to the proximal interphalangeal joint. With our method, the reconstructed interdigital space consists of 4 oblong flaps (A through D). Flaps A and D are designed on the dorsal side, flap B is designed on the frontal plane of the interdigital space, and flap C is designed on the plantar side. Flaps A, B, and C are raised immediately below the dermis in a manner that allowed slight fat tissue to adhere to each flap. Flap D is freed to a degree minimally needed for dislocation, while leaving a thick subcutaneous pedicle. Flaps A, B, and C are each folded in 90 degrees; flap D is dislocated to the proximal plane of the reconstructed digit, followed by skin suturing. In this process, suturing is avoided between flaps A and C, between flaps A and D, and between flaps B and D. During the period of 2011 to 2015, we treated 8 patients of toe syndactyly involving fusion distal to the proximal interphalangeal joint. Cases of congenital syndactyly received surgery between the ages of 8 and 11 months. Using this technique, flap ischemia/necrosis was not observed. During the postoperative follow-up period, the interdigital space retained sufficient depth without developing any scar contracture. No case required additional surgery. PMID:27536472

  11. A new skin flap method for total auricular reconstruction in microtia patients with a reconstructed ear canal: extended scalp and extended mastoid postauricular skin flaps.

    PubMed

    Hwang, Euna; Kim, Young Soo; Chung, Seum

    2014-06-01

    Before visiting a plastic surgeon, some microtia patients may undergo canaloplasty for hearing improvement. In such cases, scarred tissues and the reconstructed external auditory canal in the postauricular area may cause a significant limitation in using the posterior auricular skin flap for ear reconstruction. In this article, we present a new method for auricular reconstruction in microtia patients with previous canaloplasty. By dividing a postauricular skin flap into an upper scalp extended skin flap and a lower mastoid extended skin flap at the level of a reconstructed external auditory canal, the entire anterior surface of the auricular framework can be covered with the two extended postauricular skin flaps. The reconstructed ear shows good color match and texture, with the entire anterior surface of the reconstructed ear being resurfaced with the skin flaps. Clinical question/level of evidence; therapeutic level IV.

  12. Rescue of lip switch flap at risk of necrosis due to venous congestion for cleft lip deformity

    PubMed Central

    Sugiyama, Madoka; Saijo, Hideto; Kazuto, Hoshi; Takato, Tsuyoshi

    2016-01-01

    Abstract In a 21-year-old male with bilateral cleft lip who developed marked venous congestion of a lip switch flap, we returned the grafted flap to the donor site to improve blood circulation of the flap and then re-transplanted it, which prevented flap necrosis. Here, we report the procedure and case. PMID:27583269

  13. Rescue of lip switch flap at risk of necrosis due to venous congestion for cleft lip deformity.

    PubMed

    Sugiyama, Madoka; Saijo, Hideto; Kazuto, Hoshi; Takato, Tsuyoshi

    2016-01-01

    In a 21-year-old male with bilateral cleft lip who developed marked venous congestion of a lip switch flap, we returned the grafted flap to the donor site to improve blood circulation of the flap and then re-transplanted it, which prevented flap necrosis. Here, we report the procedure and case. PMID:27583269

  14. Treatment of postburn ear defect with expanded upper arm flap and consequent expansion without skin grafting.

    PubMed

    Hu, Jintian; Liu, Tun; Zhou, Xu; Zhang, Yong-Biao; Zhang, Qingguo

    2014-04-01

    Total ear reconstruction in the postburn auricle is one of the most challenging procedures for plastic surgeons. Adverse factors associated with these procedures include reduced or damaged blood supply, poor elasticity of scar tissue, increased risk of infection, and the possible destruction of skin, temporoparietal fascia, or retroauricular fascia. In cases where patients are severely burned, free flaps, such as radial forearm flaps, contralateral temporoparietal fascial flaps, or omental flaps, can be used as framework envelopes. In this work, we introduced a novel method of expanded upper arm flap transfer, followed by an expansion method of total ear reconstruction without skin grafting.

  15. [Resurfacing of a trochanteric pressure sore by a pedicled fasciocutaneous anterolateral thigh flap: a case report].

    PubMed

    Zeitoun, J; Faghahati, S; Burin Des Roziers, B; Daoud, G; Cartier, S

    2013-06-01

    The anterolateral thigh flap is usually used as a free flap for various kinds of reconstruction and resurfacing of distant areas. Cover of a deep trochanteric pressure sore is commonly made by muscular or musculocutaneous flaps such as tensor of fascia lata or vastus lateralis. We report the case of a trochanteric pressure sore covered by a fasciocutaneous pedicled anterolateral thigh flap after negative pressure therapy in a 58-year-old paraplegic patient. After 6 months, a good quality of coverage was obtained with minimal morbidity of donor site. The pedicled fasciocutaneous anterolateral flap appears as a reliable option for the treatment of trochanteric pressure sore.

  16. Span load distribution for tapered wings with partial-span flaps

    NASA Technical Reports Server (NTRS)

    Pearson, H A

    1937-01-01

    Tables are given for determining the load distribution of tapered wings with partial-span flaps placed either at the center or at the wing tips. Seventy-two wing-flap combinations, including two aspect ratios, four taper ratios, and nine flap lengths, are included. The distributions for the flapped wing are divided into two parts, one a zero lift distribution due primarily to the flaps and the other an additional lift distribution due to an angle of attack of the wing as a whole. Comparison between theoretical and experimental results for wings indicate that the theory may be used to predict the load distribution with sufficient accuracy for structural purposes.

  17. Posterior interosseous artery flap, fasciosubcutaneous pedicle technique: a study of 25 cases.

    PubMed

    Puri, Vinita; Mahendru, Sanjay; Rana, Roshani

    2007-01-01

    This study was undertaken in an attempt to improve the versatility of the posterior interosseous artery flap (PIA flap) and to decrease flap complication rate. The PIA flap was used for resurfacing 25 cases of the hand and distal forearm over a 2-year period. Observations were made on the anatomy of the PIA flap and its distal reach. Doppler analysis was made a mandatory part of the preoperative planning. Flaps were also raised from the zone of injury if Doppler confirmed the presence of good perforators. No attempt was made to identify the anastomosis between the anterior interosseous artery (AIA) and the PIA prior to flap raising since its presence was ascertained preoperatively with a Doppler and flap raising could begin straightway, saving precious tourniquet time. The surgical technique was further modified to include a large amount of fascia and subcutaneous tissue with the flap. This could perhaps be the reason for survival of larger flaps, absence of venous congestion and the low complication rate seen in our series. These flaps were used to resurface defects involving the dorsum of the hand, palm, distal forearm, wrist and fingers (both dorsal and volar surfaces). The distal reach of the flap was improved by exteriorising the pedicle and bowstringing it across the wrist which was kept in extension. The flap could thus easily reach the distal interphalangeal joint. This exteriorised pedicle was covered with a split thickness skin graft and was divided 3 weeks later under local anaesthesia making it a two-stage procedure. Adipofascial and osteocutaneous PIA flaps were also used depending on the requirement. Out of 25 flaps, 23 were of the adipofascial variety and one each of the fascial and osteocutaneous type. The majority of the patients were between 21 and 30 years old. Trauma was the leading cause of tissue deficit in our series (19/25). Within the trauma group occupational mishap (entrapment of hand in roller machine, presser machine, etc.) was the

  18. Wind-tunnel investigation of vortex flaps on a highly swept interceptor configuration

    NASA Technical Reports Server (NTRS)

    Schoonover, W. E., Jr.; Ohlson, W. E.

    1982-01-01

    A subsonic wind-tunnel investigation of the application of vortex flaps to a supersonic interceptor configuration is described. Experimental results are presented which indicate the aerodynamic effects of vortex-flap deflection, trailing-edge flap deflection, vortex flap chord and span, vertical stabilizers, and a highly cambered leading edge designed for attached flow. Data presented include longitudinal forces and moments, upper-surface pressure distributions, and oil- and smoke-flow visualization photographs. It is concluded that a full-span deployable vortex flap can provide a substantial performance improvement for this and other similar configurations.

  19. Total lower eyelid reconstruction with superficial temporal fascia flap and porous polyethylene implant: a case report.

    PubMed

    Sahin, Ismail; Aykan, Andac; Acikel, Cengiz; Alhan, Dogan; Isik, Selcuk

    2012-01-01

    Total reconstruction of the eyelid after serious periorbital injury is a challenging procedure for plastic and reconstructive surgery. Although several methods have been used for reconstructing the eyelids, such as advancement flap with fascia lata sling, island mucochrondrocutaneous flap, prefabricated temporal island flap, porous polyethylene and superficial temporal fascia flap, creating a supportive eyelid for housing an artificial eye without complication is still an ongoing problem. In the case presented, superficial temporal fascia flap with porous polyethylene was used for the reconstruction of total lower eyelid. PMID:21778127

  20. Free deep inferior epigastric perforator flap used for management of post-pneumonectomy space empyema.

    PubMed

    Manley, Kate; Gelvez, Sandra; Meldon, Charlotte J; Levai, Irisz; Malata, Charles M; Coonar, Aman S

    2013-04-01

    Various solutions exist for management of post-pneumonectomy space empyema. We describe the use of a free deep inferior epigastric perforator (DIEP) flap to fill the space and close a pleural window. Previously, flaps involving abdominal muscle or omentum have been used for this purpose. Abdominal surgery to harvest such flaps can impair ventilatory mechanics. The DIEP flap--harvested from the abdomen, and composed primarily of skin and muscle avoids this problem, thus is a desirable technique in patients with impaired lung function. We believe this is the first report of the DIEP flap to close a postpneumonectomy empyema space.

  1. Interpolated subcutaneous fat pedicle melolabial flap for large nasal lining defects

    PubMed Central

    Griffin, Garrett R.; Chepeha, Douglas C.; Moyer, Jeffrey S.

    2016-01-01

    Full-thickness nasal deformities are a reconstructive challenge. Restoration of a reliable internal lining is critical for a successful reconstruction. Septal hinge flaps are the workhorse for internal lining defects. However, these and other intranasal mucosal flaps are sometimes unavailable due to prior harvest or previous oncologic resection. We present the two-stage interpolated subcutaneous fat pedicle melolabial flap for lining large defects when traditional intranasal flaps are unavailable. This approach is particularly useful when one forehead flap has already been expended, preserving the patient's remaining forehead tissue for external cover. PMID:22965480

  2. Study of external dynamic flap loads on a 6 percent B-1B model

    NASA Technical Reports Server (NTRS)

    Seiner, John M.; Manning, James C.; Capone, Francis J.; Pendergraft, Odis C., Jr.

    1991-01-01

    The origin of dynamic pressure loads on external divergent engine nozzle flaps of the B-1B aircraft was investigated in the NASA/LaRC 16 foot transonic tunnel using a 6 percent full span model with powered engine nacelles. External flap dynamic loads and afterbody drag associated with flap removal were measured using this model. Both dry and max. A/B power nozzles were evaluated in this study. As a result of this study, the principal mechanisms responsible for high dynamic external flap loads were determined along with performance penalty associated with flap removal.

  3. The “Reverse” Latissimus Dorsi Flap for Large Lower Lumbar Defect

    PubMed Central

    Kotti, Bouraoui; Jaidane, Olfa; Ben Hassouna, Jamel; Rahal, Khaled

    2012-01-01

    The latissimus dorsi (LD) flap is one of the most common flaps used in plastic surgery based on its dominant thoracodorsal pedicle as well as free tissue transfer. The “distally based” or “reverse” fashion design has been used to repair myelomeningoceles, congenital diaphragmatic agenesis, or thoracolumbar defects. We present a case of a large lumbar defect after cancer resection covered by a combined tegument solution starring the “reverse” LD flap in its muscular version with a cutaneous gluteal flap. This flap is a safe and reliable way to cover large distal lumbar defect. PMID:23082273

  4. Prevention of unfavourable effects of cigarette smoke on flap viability using botulinum toxin in random pattern flaps: An experimental study

    PubMed Central

    Karayel, Hikmet; Kaya, Burak; Caydere, Muzaffer; Terzioğlu, Ahmet; Aslan, Gürcan

    2015-01-01

    BACKGROUND: There are numerous clinical and experimental studies reporting unfavourable effects of cigarette smoke on skin flaps. OBJECTIVE: To investigate whether unfavourable effects of cigarette smoke on flap survival could be reduced by botulinum toxin type A. METHODS: Twenty-eight male Wistar albino rats (15 months of age, mean weight 210 g [range 180 g to 230 g]) were included. They were divided into four groups of seven animals each. The control group underwent the surgical procedure alone. Surgical procedure was performed after administration of botulinum toxin type A in the botulinum toxin (BTX) group, after exposure to cigarette smoke in the cigarette smoke (CS) group, and after BTX type A administration and exposure to CS in the CS+BTX (CS+BTX) group. Random pattern cutaneous flaps (3 cm × 9 cm) were elevated from the dorsum of all rats. Necrosis area was calculated in percentages (%) using Image J computer software. Tissue samples were examined histopathologically. RESULTS: The mean necrotic area in the control group (26%) and in the BTX group (21%) were similar (P=0.497), whereas administration of BTX type A significantly decreased flap necrosis area in the rats exposed to CS (the mean necrosis areas were 41.5% in the CS group, and 26% in the CS+BTX group; P<0.001). Histopathological examination findings corroborated the unfavourable effects of CS and preventive effects of BTX type A. CONCLUSION: Preoperative administration of BTX significantly enhanced flap viability in the rats exposed to CS. Further human studies are warranted to verify whether BTX type A could be used as an agent to reduce the risk of flap necrosis in patients who smoke. PMID:26361625

  5. Development of a Wind Turbine Test Rig and Rotor for Trailing Edge Flap Investigation: Static Flap Angles Case

    NASA Astrophysics Data System (ADS)

    Abdelrahman, Ahmed; Johnson, David A.

    2014-06-01

    One of the strategies used to improve performance and increase the life-span of wind turbines is active flow control. It involves the modification of the aerodynamic characteristics of a wind turbine blade by means of moveable aerodynamic control surfaces. Trailing edge flaps are relatively small moveable control surfaces placed at the trailing edge of a blade's airfoil that modify the lift of a blade or airfoil section. An instrumented wind turbine test rig and rotor were specifically developed to enable a wide-range of experiments to investigate the potential of trailing edge flaps as an active control technique. A modular blade based on the S833 airfoil was designed to allow accurate instrumentation and customizable settings. The blade is 1.7 meters long, had a constant 178mm chord and a 6° pitch. The modular aerodynamic parts were 3D printed using plastic PC-ABS material. The blade design point was within the range of wind velocities in the available large test facility. The wind facility is a large open jet wind tunnel with a maximum velocity of 11m/s in the test area. The capability of the developed system was demonstrated through an initial study of the effect of stationary trailing edge flaps on blade load and performance. The investigation focused on measuring the changes in flapwise bending moment and power production for different trailing edge flap spanwise locations and deflection angles. The relationship between the load reduction and deflection angle was linear as expected from theory and the highest reduction was caused by the flap furthest from the rotor center. Overall, the experimental setup proved to be effective in measuring small changes in flapwise bending moment within the wind turbine blade and will provide insight when (active) flap control is targeted.

  6. Incisions for cochlear implant flaps and superficial skin temperature. Skin temperature/blood circulation in CI flaps.

    PubMed

    Pau, Hans Wilhelm; Sievert, Uwe; Graumüller, Sylke; Wild, Ernst

    2004-01-01

    Healing and integration of a cochlear implant is largely influenced by good blood circulation in the covering skin, which, on the other hand, is closely correlated to skin temperature. Measuring superficial flap temperatures by thermography is an easy way to get some clues about the corresponding blood supply. These data should allow some implications for the design of skin flaps in cochlear implant surgery. In 15 patients thermography was carried out prior to and after cochlear implantation, using the Agema 550 Thermovision system. It was evident, that the anatomic courses of the major superficial arteries were represented by areas of increased temperature. The pattern of temperature distribution may allow some conclusions concerning site and shape of surgical incisions. From our data we concluded, that most types of incisions do not interfere too much with the arterial blood supply. However, some types like the extended retroauricular C-incision may eventually cause problems. Our data suggest, that the straight or slightly curved vertical retroauricular incision causes the least impairment of blood circulation. After surgery, directly along the incisions (and later along the scars) temperature was diminished, indicating reduced blood circulation. In our series, the thickness of the implant did not impede blood circulation significantly. So far, we could not examine patients with local circulation disorders. Probably local scars, skin atrophies, angiopathies etc. may present typical patterns of temperature distribution, which require individual design of skin flaps. Thermography is an easy method which can give impressions of local blood circulation in skin flaps. If the courses of the major arteries and their branches are respected, blood circulation within the flap should not be problematic. Thermography is likely to help designing optimal flaps in cases with impeded blood circulation e.g. by pre-existing scar formations.

  7. A Novel Method to Estimate the Weight of the DIEP Flap in Breast Reconstruction: DIEP-W, a Simple Calculation Formula Using Paraumbilical Flap Thickness.

    PubMed

    Woo, Kyong-Je; Kim, Eun-Ji; Lee, Kyeong-Tae; Mun, Goo-Hyun

    2016-09-01

    Background Preoperative estimation of abdominal flap volume is valuable for breast reconstruction, especially in lean patients. The purpose of this study was to develop a formula to estimate the weight of the deep inferior epigastric artery perforator (DIEP) flap using unidimensional parameters. Methods We retrospectively collected data on 100 consecutive patients who underwent breast reconstruction using the DIEP flap. Multiple linear regression analysis was used to develop a formula to estimate the weight of the flap. Predictor variables included body mass index, height of the flap, width of the flap, and flap thickness on computed tomography angiographic images at three paraumbilical sites: 5 cm right, left, and inferior from the umbilicus. Then we prospectively tested the accuracy of the developed formula in 38 consecutive patients who underwent breast reconstruction with free DIEP flaps. Results A calculation formula and a smartphone application, DIEP-W was developed from retrospective analysis (R (2) = 92.7%, p < 0.001). In the prospective study, the average estimated weight was 96.3% of the actual weight, giving the formula a mean absolute percentage error of 7.7% (average differences of 45 g). The flap size in the prospective group was significantly smaller (p < 0.001) and donor-site complications were less (p = 0.002) than those of retrospective group. Conclusion Surgeons can easily calculate the DIEP weight with varying flap dimensions in a real-time fashion using this formula during preoperative planning and intraoperative design. Estimating the flap weight facilitates economical use of the flap, which can lead to reduced donor-site complications.

  8. Perforator flaps in hand reconstruction: the effect of blood vessel twisting

    PubMed Central

    ARDELEAN, FILIP; MUNTEAN, MAXIMILIAN; DUMITRASCU, DINU; STRILCIUC, STEFAN; GEORGESCU, ALEXANDRU VALENTIN

    2015-01-01

    Background and aims Perforator flaps increasingly find acceptance and use in hand reconstructive surgery. A propeller flap is an island flap that moves from one orientation to another by rotating around its vascular pedicle. It is now possible to design propeller flaps based on a single perforator, so-called “perforator-based propeller flaps,” but they are more prone to vascular impairment when twisted more than 90°. Methods We present a prospective study conducted in the Plastic and Reconstructive Surgery Department of the Rehabilitation Hospital over 17 months. All perforator-based propeller flaps that were used for hand reconstruction were analyzed. The parameters studied included the size and location of the defect, the size and shape of the flap, the perforator (length and location) that was used, the degree of twisting of the perforator, the degree of perforator dissection, the management of the donor site, and flap survival area. Results In this study we investigated the circulatory impairment induced by twisting of the pedicle on a true perforator flap. All flaps survived completely with the exception of partial skin necrosis in few cases. Some of these cases required debridement and skin grafting. Conclusions Perforator-based propeller flaps provide a reliable option for covering small- to medium-size hand complex tissue defects. They have the advantages of using similar tissues in reconstruction, not damaging another area, they do not require main vessels sacrifice, and the donor site can be generally directly closed. PMID:26609268

  9. Anterolateral thigh adipofascial flap for the restoration of facial contour deformities.

    PubMed

    Jin, Xiaolei; Teng, Li; Xu, Jiajie; Lu, Jianjian; Zhang, Chao; Zhang, Bo; Zhao, Zhenmin

    2010-07-01

    From January 2000 to May 2008, 50 patients with facial contour deformities underwent soft tissue augmentation with 51 anterolateral thigh (ALT) adipofascial flaps. Fifty flaps survived with no complications; partial fat necrosis occurred in one flap. Mean follow-up was 16 months. Flaps ranged from 10 x 6 cm to 20 x 12 cm. Perforators were found in 50 flaps, 43 musculocutaneous perforators (84.3%) and 7 septocutaneous perforators (13.7%), with a mean of 2.5 perforators per flap. In one flap (2.0%), no perforator was found. In this case, we used an anteromedial thigh adipofascial flap using the medial branch of the descending branch of lateral circumflex femoral artery as the vascular pedicle. Relatively symmetric facial contour was achieved in 20 cases. In 30 cases, adjunctive procedures including flap debulking, fat injection, and resuspension were necessary, and 23 patients achieved satisfactory outcomes. We conclude that the ALT adipofascial flap can be successfully elevated and transplanted for the correction of soft tissue facial defects. This flap can provide tissue to fill large defects, and posses the qualities of pliability, an excellent blood supply, ease of suspension and fixation, and minimal morbidity at the donor site. PMID:20049917

  10. In situ monitoring of surgical flap viability using THz imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Bajwa, Neha; Sung, Shijun; Grundfest, Warren; Taylor, Zachary

    2016-03-01

    This paper explores the utility of reflective THz imaging to assess the viability of surgical flaps. Flap surgery is a technique where tissue is harvested from a donor site and moved to a recipient while keeping the blood supply intact. This technique is common in head and neck tumor resection surgery where the reconstruction of complex and sensitive anatomic structures is routine following the resection of large and/or invasive tumors. Successful flap surgery results in tissue that is sufficiently perfused with both blood and extracellular water. If insufficient fluid levels are maintained, the flap tissue becomes necrotic and must be excised immediately to prevent infection developing and spreading to the surrounding areas. The goal of this work is to investigate the hydration of surgical flaps and correlate image features to successful graft outcomes. Advancement flaps were created on the abdomens of rat models. One rat model was labeled control and care was taken to ensure a successful flap outcome. The flap on the second rat was compromised with restricted blood flow and allowed to fail. The flaps of both rats were imaged once a day over the course of a week at which point the compromised flap had begun to show signs of necrosis. Significant differences in tissue water content were observed between rats over the experimental period. The results suggest that THz imaging may enable early assessment of flap viability.

  11. Effect of intraoperative platelet-rich plasma and fibrin glue application on skin flap survival.

    PubMed

    Findikcioglu, Fulya; Findikcioglu, Kemal; Yavuzer, Reha; Lortlar, Nese; Atabay, Kenan

    2012-09-01

    The experiment was designed to compare the effect of intraoperative platelet-rich plasma (PRP) and fibrin glue application on skin flap survival. In this study, bilateral epigastric flaps were elevated in 24 rats. The right-side flaps were used as the control of the left-side flaps. Platelet-rich plasma, fibrin glue, and thrombin had been applied under the flap sites in groups 1, 2, and 3, respectively. Five days later, all flap pedicles were ligated. Necrotic area measurements, microangiography, and histologic and immunohistochemical evaluations were performed to compare the groups. Platelet-rich plasma reduced necrotic area percentages as compared with other groups. Histologically and microangiographically increased number of arterioles were observed in PRP groups. Thrombin when used alone increased flap necrosis. Vascular endothelial growth factor, platelet-derived growth factor, and transforming growth factor β3 primary antibody staining showed increased neovascularization and reepithelialization in all PRP-applied flaps. This study demonstrated that PRP, when applied intraoperatively under the skin flap, may enhance flap survival. Thrombin used alone was found to be unsuitable in flap surgery.

  12. Reconstruction of cubital fossa skin necrosis with radial collateral artery perforator-based propeller flap (RCAP).

    PubMed

    Chaput, B; Gandolfi, S; Ho Quoc, C; Chavoin, J-P; Garrido, I; Grolleau, J-L

    2014-02-01

    In recent years, perforator flaps have become an indispensable tool for the reconstruction process. Most recently, "propeller" perforator flaps allow each perforator vessels to become a flap donor site. Once the perforator of interest is identified by acoustic Doppler, the cutaneous or fascio-cutaneous island is designed and then customized according to the principle of "perforasome". So, the flap can be rotated such a propeller, up to 180°. Ideally the donor site is self-closing, otherwise it can be grafted at the same time. Through a skin necrosis secondary to a contrast medium extravasation of the cubital fossa in a 47-year-old man, we describe the use of propeller perforator flap based on a perforator of the radial collateral artery (RCAP). The perforator was identified preoperatively by acoustic Doppler then the flap was adapted bespoke to cover the loss of substance. Ultimately, the result was very satisfying. Well experienced for lower-extremity reconstruction, perforator-based propeller flap are still few reported for upper limb. It is likely that in the future, propeller flap supersede in many indication not only free flaps and locoregional flaps but also, leaving no room for uncertainties of the vascular network, the classic random flaps.

  13. Effects of Wing Platform on the Aerodynamic Performance of Finite-Span Flapping Wings

    NASA Astrophysics Data System (ADS)

    Yu, Meilin; Wang, Z. J.; Hu, Hui

    2010-11-01

    A numerical study is conducted to investigate the effects of wing platform on the aerodynamics performance of finite-span flapping wings. A three-dimensional high-order Navier-Stokes compressible flow solver was developed using the spectral difference method and dynamic grids. An AUSM^+-up Riemann solver was implemented to simulate the unsteady low Mach number flows over finite-span flapping wings with explicit third order Runge-Kutta time integration. The studied finite-span flapping wings, which include a rectangular flapping wing, an elliptic flapping wing and a bio-inspired flapping wing, have the same wing span, aspect ratio of the platform and the characteristics of the flapping motion (i.e., sinusoidal trajectory of the flapping wing tip, Strouhal number and reduced frequency). In the present study, the Strouhul number (Str) of the finite-span flapping wings was selected to be well within the optimal range usually used by flying insects and birds and swimming fishes (i.e., 0.2 < Str < 0.4). The effects of the wing platform on the aerodynamics performance of the finite-span flapping wings were elucidated in the terms of the evolutions and dynamic interaction between the leading edge vortices (LEV) and the wing tip vortices as well as the resultant aerodynamic forces (both lift and thrust) generated by the flapping wings.

  14. Noise reduction tests of large-scale-model externally blown flap using trailing-edge blowing and partial flap slot covering. [jet aircraft noise reduction

    NASA Technical Reports Server (NTRS)

    Mckinzie, D. J., Jr.; Burns, R. J.; Wagner, J. M.

    1976-01-01

    Noise data were obtained with a large-scale cold-flow model of a two-flap, under-the-wing, externally blown flap proposed for use on future STOL aircraft. The noise suppression effectiveness of locating a slot conical nozzle at the trailing edge of the second flap and of applying partial covers to the slots between the wing and flaps was evaluated. Overall-sound-pressure-level reductions of 5 db occurred below the wing in the flyover plane. Existing models of several noise sources were applied to the test results. The resulting analytical relation compares favorably with the test data. The noise source mechanisms were analyzed and are discussed.

  15. Distally based posterior interosseous flap: primary role in soft-tissue reconstruction of the hand.

    PubMed

    Agir, Hakan; Sen, Cenk; Alagöz, Sahin; Onyedi, Murat; Isil, Eda

    2007-09-01

    A series of 15 consecutive patients with various hand defects requiring flap coverage was reviewed in this study. The defects were all covered with the distally based posterior interosseous flap. Its main indications were in complex hand trauma, severe burn injury, or skin cancer ablation, either acute or postprimary. In 12 of the patients, flaps survived completely. In 3 patients, there was partial necrosis of the distal part of the flap, which did not require additional surgical procedure. Radial nerve palsy was noted in one of the cases, with a complete recovery after 3 months. Donor site was closed directly in up to 4-cm-wide flaps, while larger flaps required skin grafting. No major anatomic variation was observed. Distally based posterior interosseous flap is a reliable choice for various types and areas of hand defects, with very low donor-site morbidity, and should be more commonly considered in clinical practice.

  16. Free Flap Elevation Times in Head and Neck Reconstruction Using the Harmonic Scalpel Shears

    PubMed Central

    DeSerres, Joshua J.; Barber, Brittany R.; Seikaly, Hadi; Harris, Jeffrey R.

    2016-01-01

    Summary: Free tissue transfer has become the mainstay of head and neck cancer (HNC) reconstructive surgery. The objective of the study is to examine the efficacy of the Harmonic Scalpel (HS) Shears on free flap elevation time and complication rates after HNC reconstruction compared with traditional electrocautery. A retrospective review of 215 HNC patients undergoing surgical ablation and free flap reconstruction from January 2010 to April 2013 at the University of Alberta Hospital was undertaken. All patients requiring free flap reconstruction with radial forearm free flap or fibula free flap were included. Overall, there was no significant difference demonstrated between the HS and electrocautery groups for free flap elevation time for RFFFs (P = 0.563) or FFFs (P = 0.087). No differences were observed in donor-site complications. The HS is a reliable, safe, and alternative method of free flap elevation in HNC reconstructive surgery. PMID:27579242

  17. Dynamic perfusion assessment during perforator flap surgery: an up-to-date

    PubMed Central

    MUNTEAN, MAXIMILIAN VLAD; MUNTEAN, VALENTIN; ARDELEAN, FILIP; GEORGESCU, ALEXANDRU

    2015-01-01

    Flap monitoring technology has progressed alongside flap design. The highly variable vascular anatomy and the complexity associated with modern perforator flaps demands dynamic, real-time, intraoperative information about the vessel location, perfusion patterns and flap physiology. Although most surgeons still assess flap perfusion and viability based solely on clinical experience, studies have shown that results may be highly variable and often misleading. Poor judgment of intraoperative perfusion leads to major complications. Employing dynamic perfusion imaging during flap reconstruction has led to a reduced complication rate, lower morbidity, shorter hospital stay, and an overall better result. With the emergence of multiple systems capable of intraoperative flap evaluation, the purpose of this article is to review the two systems that have been widely accepted and are currently used by plastic surgeons: Indocyanine green angiography (ICGA) and dynamic infrared thermography (DIRT). PMID:26609259

  18. Effects of vascular endothelial growth factor on survival of surgical flaps: a review of experimental studies.

    PubMed

    Fang, Taolin; Lineaweaver, William C; Chen, Michael B; Kisner, Carson; Zhang, Feng

    2014-01-01

    Partial or complete necrosis of skin flaps remains a significant problem in plastic and reconstructive surgery. Growth factors have shown promise in improving flap survival through increased angiogenesis and blood supply to the flap. Vascular endothelial growth factor (VEGF) is the most widely investigated and successful one. But the mechanisms of the effects are still not very clear. In the course of a series of experiments, we indicated that tissue survival of surgical flaps could be improved by both preoperative (sustained phase effect) and intraoperative (acute phase effect) application of VEGF. We reviewed both experimental and clinical investigations on the use of VEGF with surgical flaps to summarize the evidence of both phases of VEGF activity in promotion of flaps survival in detail. With the combinations of acute and sustained phases of effects, VEGF protein and gene, VEGF morphologic actions, and VEGF histochemical modulations suggest a pattern of VEGF activity that can be superimposed on classic descriptive mechanisms of tissue survival of flaps.

  19. Pressure investigation of NASA leading edge vortex flaps on a 60 deg Delta wing

    NASA Technical Reports Server (NTRS)

    Marchman, J. F., III; Donatelli, D. A.; Terry, J. E.

    1983-01-01

    Pressure distributions on a 60 deg Delta Wing with NASA designed leading edge vortex flaps (LEVF) were found in order to provide more pressure data for LEVF and to help verify NASA computer codes used in designing these flaps. These flaps were intended to be optimized designs based on these computer codes. However, the pressure distributions show that the flaps wre not optimum for the size and deflection specified. A second drag-producing vortex forming over the wing indicated that the flap was too large for the specified deflection. Also, it became apparent that flap thickness has a possible effect on the reattachment location of the vortex. Research is continuing to determine proper flap size and deflection relationships that provide well-behaved flowfields and acceptable hinge-moment characteristics.

  20. The use of the pedicled supraclavicular flap in noma reconstructive surgery.

    PubMed

    Hartman, Ed H M; Van Damme, Philip A; Sauter, Hartwig; Suominen, Sinikka H H

    2006-01-01

    Three noma patients with large unilateral facial defects were reconstructed using the pedicled supraclavicular flap technique in the Noma Children Hospital in Sokoto, Nigeria. The results are-although not completely perfect-encouraging enough to report and to repeat the technique in future reconstructive noma surgery after moderate modifications. It is advised not to tunnel the pedicle in the neck, but instead to open the neck. Then, the flap can be inset in a Z-plasty fashion to close the neck without the chance of compression of the pedicle of the flap. In this way flap necrosis can be prevented, without the risk of a scar contracture of the neck. Another technique, which can prevent partial flap necrosis and loss of tissue, with the need for secondary stage interventions, is a delay procedure of the flap. Incorporation of the fascia in the pedicled supraclavicular flap can be another option to fulfil the abovementioned requirements.

  1. Tadalafil significantly reduces ischemia reperfusion injury in skin island flaps

    PubMed Central

    Kayiran, Oguz; Cuzdan, Suat S.; Uysal, Afsin; Kocer, Ugur

    2013-01-01

    Introduction: Numerous pharmacological agents have been used to enhance the viability of flaps. Ischemia reperfusion (I/R) injury is an unwanted, sometimes devastating complication in reconstructive microsurgery. Tadalafil, a specific inhibitor of phosphodiesterase type 5 is mainly used for erectile dysfunction, and acts on vascular smooth muscles, platelets and leukocytes. Herein, the protective and therapeutical effect of tadalafil in I/R injury in rat skin flap model is evaluated. Materials and Methods: Sixty epigastric island flaps were used to create I/R model in 60 Wistar rats (non-ischemic group, ischemic group, medication group). Biochemical markers including total nitrite, malondialdehyde (MDA) and myeloperoxidase (MPO) were analysed. Necrosis rates were calculated and histopathologic evaluation was carried out. Results: MDA, MPO and total nitrite values were found elevated in the ischemic group, however there was an evident drop in the medication group. Histological results revealed that early inflammatory findings (oedema, neutrophil infiltration, necrosis rate) were observed lower with tadalafil administration. Moreover, statistical significance (P < 0.05) was recorded. Conclusions: We conclude that tadalafil has beneficial effects on epigastric island flaps against I/R injury. PMID:23960309

  2. Total Lip Reconstruction with Tendinofasciocutaneous Radial Forearm Flap

    PubMed Central

    Silberstein, Eldad; Krieger, Yuval; Shoham, Yaron; Arnon, Ofer; Sagi, Amiram; Bogdanov-Berezovsky, Alexander

    2014-01-01

    Introduction. Squamous cell carcinoma is a common tumour of lower lip. Small defects created by surgical resection may be readily reconstructed by linear closure or with local flaps. However, large tumours resection often results with microstomia and oral incompetence, drooling, and speech incomprehension. The goal of this study is to describe our experience with composite free radial forearm-palmaris longus tendon flap for total or near total lower lip reconstruction. Patients and Methods. This procedure was used in 5 patients with 80–100% lip defect resulting from Squamous cell carcinoma. Patients' age ranged from 46 to 82 years. They are three male patients and two female. In 3 cases chin skin was reconstructed as well and in one case a 5 cm segment of mandible was reconstructed using radius bone. In one case where palmaris longus was missing hemi-flexor carpi radialis tendon was used instead. All patients tolerated the procedure well. Results. All flaps totally survived. No patient suffered from drooling. All patients regained normal diet and normal speech. Cosmetic result was fair to good in all patients accept one. Conclusion. We conclude that tendino-fasciocutaneous radial forearm flap for total lower lip reconstruction is safe. Functional and aesthetic result approaches reconstructive goals. PMID:24672301

  3. Forward flight of swallowtail butterfly with simple flapping motion.

    PubMed

    Tanaka, Hiroto; Shimoyama, Isao

    2010-06-01

    Unlike other flying insects, the wing motion of swallowtail butterflies is basically limited to flapping because their fore wings partly overlap their hind wings, structurally restricting the feathering needed for active control of aerodynamic force. Hence, it can be hypothesized that the flight of swallowtail butterflies is realized with simple flapping, requiring little feedback control of the feathering angle. To verify this hypothesis, we fabricated an artificial butterfly mimicking the wing motion and wing shape of a swallowtail butterfly and analyzed its flights using images taken with a high-speed video camera. The results demonstrated that stable forward flight could be realized without active feathering or feedback control of the wing motion. During the flights, the artificial butterfly's body moved up and down passively in synchronization with the flapping, and the artificial butterfly followed an undulating flight trajectory like an actual swallowtail butterfly. Without feedback control of the wing motion, the body movement is directly affected by change of aerodynamic force due to the wing deformation; the degree of deformation was determined by the wing venation. Unlike a veinless wing, a mimic wing with veins generated a much higher lift coefficient during the flapping flight than in a steady flow due to the large body motion.

  4. [Oromandibular reconstruction with free peroneal flap and osseointegrated implants].

    PubMed

    Navarro Cuéllar, C; Cuesta Gil, M; Plasencia Delgado, J; Guerra Martínez, B; Acero Sanz, J; López de Atalaya, F J; Ochandiano Caicoya, S; Navarro Vila, C

    2003-01-01

    Free fibula flaps have proved to be one of the most versatile for oromandibular reconstruction due to the available length of bone and the possibility of incorporating a long skin paddle to cover intraoral soft tissues. The use of a osseointegrated dental implants is an important technique for the oral rehabilitation of these patients. Osseointegrated implants provide the most rigid prosthetic stabilization available to withstand masticatory forces. These implants can be placed immediately or in second time procedure. In our case, implantation in the fibula free flap is done after 6-9 months because of the large amount of osteosynthesis material required for the fixation of the flap. Four or six months later, when osseointegration has taken place, the implants are loaded with a dental rehabilitation. We analize 10 cases of mandibular reconstruction with fibula free flap and their aesthetic and functional rehabilitation with osseointegrated implants with a 2 year follow up. Forty-six dental implants were placed developing all of them but one a correct osseointegration. All these patients recovered masticatory function and underwent a considerable improvement in labial competence, salivary continence, speech articulation and facial harmony.

  5. Effect of Tisseel on healing after periodontal flap surgery.

    PubMed

    Warrer, K; Karring, T

    1992-08-01

    The purpose of this investigation was to evaluate the effect on healing of fast and slow absorbable Tisseel in combination with periodontal flap surgery. Mucoperiosteal flaps were raised on the buccal aspect of maxillary premolars and mandibular premolars and first molars in 4 beagle dogs. The underlying buccal, interproximal and inter-radicular bone was then removed to a level of approximately 5 mm apically to the original bone crest and half way into the interdental spaces and bifurcations. The exposed root surfaces were curetted in order to remove the periodontal ligament tissue, and a notch was made in the root surface at the base of the defects. On the control teeth, the flaps were sutured immediately after creation of the defects, while on the test teeth, a layer of fast (group I) or slow (group II) absorbable Tisseel was applied between the curetted roots and the subsurface of the flaps prior to suturing. Postoperatively, the teeth were brushed 2 x weekly. The dogs were sacrificed after 4 months. Histological analysis revealed that the amounts of new attachment and bone regrowth were similar in the test and control groups, although the results tended to be most favorable for the group of teeth treated with fast absorbable Tisseel (Group I).

  6. Inverted Internal Limiting Membrane Flap For Large Traumatic Macular Holes

    PubMed Central

    Abou Shousha, Mohsen Ahmed

    2016-01-01

    Abstract The aim of the study was to assess the role of inverted internal limiting membrane flap as a treatment option for large traumatic macular holes. This is a prospective noncomparative study in which 12 eyes with large traumatic macular holes (basal diameter of 1300–2800 μm) since 3 to 6 months were subjected to standard 23-gauge vitrectomy with removal of the posterior hyaloid, brilliant blue G (BBG)-assisted internal limiting membrane peeling in a circular fashion keeping it attached to the edge of the hole to create a flap. At the end of the surgery, air fluid exchange was done with inversion of the internal limiting membrane flap inside the macular hole using the soft tipped cannula and sulfur hexafluoride 20% as tamponade. The main follow-up measures are the best corrected visual acuity and the optical coherence tomography for 6 to 9 months. All the included eyes had a closed hole from the first week postoperative and along the follow-up period (6–9 months). The best corrected visual acuity improved from 20/2000 to 20/200 with a median of 20/400 preoperatively to 20/400 to 20/50 with a median of 20/100 at the end of follow-up period. Inverted internal limiting membrane flap is a good adjuvant to standard vitrectomy in the management of large traumatic macular holes that led to the 100% closure rate and improvement of best corrected visual acuity. PMID:26817894

  7. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... sides of the plane of symmetry must be synchronized by a mechanical interconnection or approved... engines on one side of the plane of symmetry inoperative and the remaining engines at takeoff power. (c... resulting when interconnected flap or slat surfaces on one side of the plane of symmetry are jammed...

  8. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... sides of the plane of symmetry must be synchronized by a mechanical interconnection or approved... engines on one side of the plane of symmetry inoperative and the remaining engines at takeoff power. (c... resulting when interconnected flap or slat surfaces on one side of the plane of symmetry are jammed...

  9. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... sides of the plane of symmetry must be synchronized by a mechanical interconnection or approved... engines on one side of the plane of symmetry inoperative and the remaining engines at takeoff power. (c... resulting when interconnected flap or slat surfaces on one side of the plane of symmetry are jammed...

  10. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... sides of the plane of symmetry must be synchronized by a mechanical interconnection or approved... engines on one side of the plane of symmetry inoperative and the remaining engines at takeoff power. (c... resulting when interconnected flap or slat surfaces on one side of the plane of symmetry are jammed...

  11. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... sides of the plane of symmetry must be synchronized by a mechanical interconnection or approved... engines on one side of the plane of symmetry inoperative and the remaining engines at takeoff power. (c... resulting when interconnected flap or slat surfaces on one side of the plane of symmetry are jammed...

  12. The role of passive avian head stabilization in flapping flight

    PubMed Central

    Pete, Ashley E.; Kress, Daniel; Dimitrov, Marina A.; Lentink, David

    2015-01-01

    Birds improve vision by stabilizing head position relative to their surroundings, while their body is forced up and down during flapping flight. Stabilization is facilitated by compensatory motion of the sophisticated avian head–neck system. While relative head motion has been studied in stationary and walking birds, little is known about how birds accomplish head stabilization during flapping flight. To unravel this, we approximate the avian neck with a linear mass–spring–damper system for vertical displacements, analogous to proven head stabilization models for walking humans. We corroborate the model's dimensionless natural frequency and damping ratios from high-speed video recordings of whooper swans (Cygnus cygnus) flying over a lake. The data show that flap-induced body oscillations can be passively attenuated through the neck. We find that the passive model robustly attenuates large body oscillations, even in response to head mass and gust perturbations. Our proof of principle shows that bird-inspired drones with flapping wings could record better images with a swan-inspired passive camera suspension. PMID:26311316

  13. The role of passive avian head stabilization in flapping flight.

    PubMed

    Pete, Ashley E; Kress, Daniel; Dimitrov, Marina A; Lentink, David

    2015-09-01

    Birds improve vision by stabilizing head position relative to their surroundings, while their body is forced up and down during flapping flight. Stabilization is facilitated by compensatory motion of the sophisticated avian head-neck system. While relative head motion has been studied in stationary and walking birds, little is known about how birds accomplish head stabilization during flapping flight. To unravel this, we approximate the avian neck with a linear mass-spring-damper system for vertical displacements, analogous to proven head stabilization models for walking humans. We corroborate the model's dimensionless natural frequency and damping ratios from high-speed video recordings of whooper swans (Cygnus cygnus) flying over a lake. The data show that flap-induced body oscillations can be passively attenuated through the neck. We find that the passive model robustly attenuates large body oscillations, even in response to head mass and gust perturbations. Our proof of principle shows that bird-inspired drones with flapping wings could record better images with a swan-inspired passive camera suspension.

  14. Adjacent flaps for lower lip reconstruction after mucocele resection.

    PubMed

    Ying, Binbin

    2012-03-01

    Mucocele forms because of salivary gland mucous extravasation or retention and is usually related to trauma in the area of the lower lip. It is a common benign lesion in the oral region. Although there are many conservative treatments such as the creation of a pouch (marsupialization), freezing (cryosurgery), micromarsupialization, and CO2 laser vaporization, surgical resection is the most commonly used means. Generally speaking, an elliptic incision was made to fully enucleate the lesion along with the overlying mucosa and the affected glands, then direct suturing is adequate. However, in some cases, direct suturing could cause lower lip deformity, and adjacent flaps for lower lip reconstruction after mucocele resection might be quite necessary. Based on our experience, adjacent mucosal flaps could be used when lesions were close to or even break through the vermilion border or their diameters were much more than 1 cm. A-T advancement flaps and transposition flaps were the mostly applied ones. Follow-up showed that all patients realized primary healing after 1 week postoperatively with satisfactory lower lip appearance, and there was no sign of increasing incidence of relapse. PMID:22421867

  15. The Japanese Flap in EFL: Variability and Accent.

    ERIC Educational Resources Information Center

    Riney, Timothy J.; Takada, Mari

    1998-01-01

    A study investigated the substitution of the Japanese flap for English liquids /r/ and /l/ by 11 Japanese students in their first and fourth years of college. Phonological patterns were examined at the two different stages, in reading vs. spontaneous oral language tasks, and for word-initial singleton vs. word-initial cluster environments. The…

  16. EBF noise suppression and aerodynamic penalties. [Externally Blown Flaps

    NASA Technical Reports Server (NTRS)

    Mckinzie, L. J., Jr.

    1978-01-01

    Acoustic tests were conducted at model scale to determine the noise produced in the flyover and sideline planes at reduced separation distances between the nozzle exhaust plane and the flaps of an under-the-wing (UTW) externally blown flap (EBF) configuration in its approach attitude. Tests were also made to determine the noise suppression effectiveness of two types of passive devices which were located on the jet impingement surfaces of the configuration. In addition, static aerodynamic performance data were obtained to evaluate the penalties produced by these suppression devices. Broadband low frequency noise reductions were achieved by reducing the separation distance between the nozzle and flaps. However, mid and high frequency noise was produced which exceeded that of the reference configuration. Two passive noise suppression devices located on the flaps produced moderate to large noise reductions at reduced separation distances. Consideration of the static aerodynamic performance data obtained for the configurations tested suggests that specific broadband noise suppression characteristics may be obtained through a trade-off with aerodynamic performance penalties by the careful selection of suppression devices.

  17. 6. CLOSEUP VIEW OF THE PUMP DISCHARGE CHANNEL, THE FLAP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. CLOSEUP VIEW OF THE PUMP DISCHARGE CHANNEL, THE FLAP VALVES OF THE PUMPING UNITS 8, 6, AND 7 (L TO R) AND PART OF THE DISCHARGE WEIR OF THE INDIVIDUAL DISCHARGE CHAMBER OF PUMP NO. 5, LOOKING NORTHEAST. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

  18. The role of passive avian head stabilization in flapping flight.

    PubMed

    Pete, Ashley E; Kress, Daniel; Dimitrov, Marina A; Lentink, David

    2015-09-01

    Birds improve vision by stabilizing head position relative to their surroundings, while their body is forced up and down during flapping flight. Stabilization is facilitated by compensatory motion of the sophisticated avian head-neck system. While relative head motion has been studied in stationary and walking birds, little is known about how birds accomplish head stabilization during flapping flight. To unravel this, we approximate the avian neck with a linear mass-spring-damper system for vertical displacements, analogous to proven head stabilization models for walking humans. We corroborate the model's dimensionless natural frequency and damping ratios from high-speed video recordings of whooper swans (Cygnus cygnus) flying over a lake. The data show that flap-induced body oscillations can be passively attenuated through the neck. We find that the passive model robustly attenuates large body oscillations, even in response to head mass and gust perturbations. Our proof of principle shows that bird-inspired drones with flapping wings could record better images with a swan-inspired passive camera suspension. PMID:26311316

  19. Detail view of the underside of the Body Flap of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of the underside of the Body Flap of the Orbiter Discovery as it is being rotated into a vertical position in the Vehicle Assembly Building at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  20. Aeroacoustic Evaluation of Flap and Landing Gear Noise Reduction Concepts

    NASA Technical Reports Server (NTRS)

    Khorrami, Mehdi R.; Humphreys, William M., Jr.; Lockard, David P.; Ravetta, Patricio A.

    2014-01-01

    Aeroacoustic measurements for a semi-span, 18% scale, high-fidelity Gulfstream aircraft model are presented. The model was used as a test bed to conduct detailed studies of flap and main landing gear noise sources and to determine the effectiveness of numerous noise mitigation concepts. Using a traversing microphone array in the flyover direction, an extensive set of acoustic data was obtained in the NASA Langley Research Center 14- by 22-Foot Subsonic Tunnel with the facility in the acoustically treated open-wall (jet) mode. Most of the information was acquired with the model in a landing configuration with the flap deflected 39 deg and the main landing gear alternately installed and removed. Data were obtained at Mach numbers of 0.16, 0.20, and 0.24 over directivity angles between 56 deg and 116 deg, with 90 deg representing the overhead direction. Measured acoustic spectra showed that several of the tested flap noise reduction concepts decrease the sound pressure levels by 2 - 4 dB over the entire frequency range at all directivity angles. Slightly lower levels of noise reduction from the main landing gear were obtained through the simultaneous application of various gear devices. Measured aerodynamic forces indicated that the tested gear/flap noise abatement technologies have a negligible impact on the aerodynamic performance of the aircraft model.

  1. DETAIL OF GASPROOF DOOR SHOWING THE THREE ROUND FLAP VALVES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF GAS-PROOF DOOR SHOWING THE THREE ROUND FLAP VALVES AT THE BASE OF THE DOOR - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, Battery Command Center, Ford Island, Pearl City, Honolulu County, HI

  2. A Rapid, Simple, Effective, and Inexpensive Reconstructed Nipple Flap Guard

    PubMed Central

    Khan, Khurrum

    2015-01-01

    Summary: Nipple reconstruction is a commonly performed component of breast reconstruction. A nipple reconstructed using local skin flaps requires protection from trauma. Here we describe a novel, effective, simple, rapid, inexpensive, and convenient method to protect a reconstructed nipple in the early postoperative period. PMID:26579352

  3. Local Vascularized Flaps for Augmentation of Reinke’s Space

    PubMed Central

    Dailey, Seth H.; Gunderson, McLean; Chan, Roger; Torrealba, Jose; Kimura, Miwako; Welham, Nathan V.

    2011-01-01

    Objectives/Hypothesis The purpose of this study is to describe and test a novel surgical strategy for augmentation of Reinke’s space using vascularized flaps: a thyroid ala perichondrium flap (TAP) and a composite thyroid ala perichondrium flap (CTAP) from the anterior larynx. We hypothesized that these specially designed vascularized flaps would remain viable once inset into the lamina propria, and that they would not disrupt rheologic, biomechanical, and histologic properties of the native vocal fold. Study Design Experimental. In vivo canine model. Methods The length and volume of test flaps harvested in six adult human cadaveric larynges were analyzed to determine suitability for use in augmentation in the lamina propria. Also, 12 beagles randomly underwent unilateral placement of either TAP or CTAP, which were designed in accordance with the human adult cadaveric experiments. Flap perfusion was measured before and after harvest with laser Doppler. After 1 month, the beagles were humanely sacrificed and their larynges subjected to aerodynamic and acoustic evaluation using an excised larynx apparatus. The vocal fold lamina propria of four larynges—two TAP and two CTAP—underwent rheologic evaluation using a simple-shear rheometer. The remaining eight larynges underwent quantitative histologic and immunohistochemical evaluation. The survival and complication (swallowing, airway, local wound) rates of all dogs were noted. Results Initial studies with adult human cadaveric larynges established that TAP and CTAP possessed length and volume greater than native lamina propria. In the canine experiments, the perfusion change in the flaps was similar between flap groups. The damping ratio (ζ), dynamic viscosity (η′), elastic shear modulus (G′), and viscous shear modulus (G″) of treated and untreated native vocal folds were not statistically different. The glottic function measures of vocal efficiency, laryngeal resistance, jitter, shimmer, and harmonics

  4. Flexible flapping wings with self-organized microwrinkles.

    PubMed

    Tanaka, Hiroto; Okada, Hiroyuki; Shimasue, Yosuke; Liu, Hao

    2015-08-01

    Bio-inspired flapping wings with a wrinkled wing membrane were designed and fabricated. The wings consist of carbon fibre-reinforced plastic frames and a polymer film with microscale wrinkles inspired by bird feathers and the corrugations of insect wings. The flexural and tensile stiffness of the wrinkled film can be controlled by modifying the orientations and waveforms of the wrinkles, thereby expanding the design space of flexible wings for micro flapping-wing aerial robots. A self-organization phenomenon was exploited in the fabrication of the microwrinkles such that microscale wrinkles spanning a broad wing area were spontaneously created. The wavy shape of these self-organized wrinkles was used as a mould, and a Parylene film was deposited onto the mould to form a wrinkled wing film. The effect of the waveforms of the wrinkles on the film stiffness was investigated theoretically, computationally and experimentally. Compared with a flat film, the flexural stiffness was increased by two orders of magnitude, and the tensile stiffness was reduced by two orders of magnitude. To demonstrate the effect of the wrinkles on the actual deformation of the flapping wings and the resulting aerodynamic forces, the fabricated wrinkled wings were tested using a tethered electric flapping mechanism. Chordwise unidirectional wrinkles were found to prevent fluttering near the trailing edge and to produce a greater aerodynamic lift compared with a flat wing or a wing with spanwise wrinkles. Our results suggest that the fine stiffness control of the wing film that can be achieved by tuning the microwrinkles can improve the aerodynamic performance of future flapping-wing aerial robots. PMID:26119657

  5. Orandi flap for penile urethral stricture: Polishing the gold standard

    PubMed Central

    Goel, Apul; Kumar, Manoj; Singh, Manmeet

    2015-01-01

    Introduction: We describe the combined use of the Orandi flap and the scrotal skin advancement flap to reduce complications for pendulous urethral stricture in men >40 years old. Methods: Over the last 40 months, 10 men underwent urethroplasty for pendulous stricture by the modified Orandi urethroplasty. In this, additionally, a midline hairless scrotal skin flap of the size of the ventral skin defect on the pendulous portion was raised based on the dartos fascia. This flap was mobilized so that it reached the pendulous portion without tension and covered the penile defect. The catheter was removed after 4 weeks. Patients were followed every 3 months using uroflowmetry and the American Urological Association (AUA) symptom score. Results: The mean age was 55.5. Of the 10 patients, the etiology was post-catheterization in 5 and idiopathic in the remaining 5. Three men also had stricture extending into the bulbous urethra (repaired using buccal graft). The mean additional time needed for the flap coverage was 36.2 minutes (range: 30–45). The median follow-up was 12 months (range: 3–40). The mean postoperative symptom score was 5.2 and the mean flow rate was 20.1 mL/sec. In 2 men, the meatus got retracted to the distal penile part (probably due to downward traction by scrotal skin). No patient complained of disfigurement. Two men reported recurrence (1 each in bulbous and penile urethra). The limitations are small number of patients and the observational nature of this study. Conclusions: The intermediate-term results show that the modified Orandi urethroplasty is an acceptable treatment option with acceptable cosmetic results. PMID:26085873

  6. Wound Dehiscence after Wisdom Tooth Removal in Mandibular Mesioangular Class IB Impactions: Triangular Transposition Flap versus Envelope Flap.

    PubMed

    Rahpeyma, Amin; Khajehahmadi, Saeedeh; Ilkhani, Sina

    2015-01-01

    Background and aims. Wound dehiscence after lower third molar surgery extends the postoperative treatment period and may cause long-standing pain. The aim of this study was to compare wound dehiscence after removal of wisdom teeth in the most prevalent mandibular impaction (mesioangular class IB) by two different soft tissue flap designs. Materials and methods. Partially-erupted mandibular third molars with mesioangular class IB impaction (Pell and Gregory classification) were selected. Split mouth technique was used to compare the two flap designs (envelope vs. triangular transposition flap-TTF). The patients were recalled one week and a month later and rechecked for dehiscence, infection, and dry socket formation. Results. There were no cases of infection in either group. However, three cases of dry socket in the envelope group and four in the TTF group were recorded. In the envelope group, dehiscence occurred in 43% of cases during the first week, with 67% of cases being a large dehiscence (diameters of more than 5 mm). Extra appointments (those requested by the patient exclusively related to the problem of the hole distal to the second molar) were scheduled in 10% of cases in the envelope group. In the TTF group, dehiscence occurred during the first week for the same impaction in 19% of cases with large dehiscence cases occurring in 65% of cases and extra appointment rate at 4.1%. Conclusion. According to theresults in the evaluated operation, TTF may prevent postoperative wound dehiscence more probably than the envelope flap.

  7. Dynamic properties of blood flow and leukocyte mobilization in infected flaps

    SciTech Connect

    Feng, L.J.; Price, D.C.; Mathes, S.J.; Hohn, D. )

    1990-11-01

    Two aspects of the inflammatory response to infection--blood flow alteration and leukocyte mobilization--are investigated in the canine model. The elevation of paired musculocutaneous (MC) and random pattern (RP) flaps allowed comparison of healing flaps with significant differences in blood flow (lower in random pattern flaps) and resistance to infection (greater in musculocutaneous flaps). Blood flow changes as determined by radioactive xenon washout were compared in normal skin and distal flap skin both after elevation and following bacterial inoculation. Simultaneous use of In-111 labeled leukocytes allowed determination of leukocyte mobilization and subsequent localization in response to flap infection. Blood flow significantly improved in the musculocutaneous flap in response to infection. Although total leukocyte mobilization in the random pattern flap was greater, the leukocytes in the musculocutaneous flap were localized around the site of bacterial inoculation within the dermis. Differences in the dynamic blood flow and leukocyte mobilization may, in part, explain the greater reliability of musculocutaneous flaps when transposed in the presence of infection.

  8. Versatility of free SCIA/SIEA flaps in head and neck defects.

    PubMed

    Nasir, Serdar; Aydin, Mustafa Asim

    2010-07-01

    Reconstruction of head and neck defects may require replacement of the bony structures, external soft tissue, and intraoral mucosa. Most cases, including maxillary defects, often require repair using only soft tissue flaps. Recently, the authors used free superficial circumflex iliac artery/superficial inferior epigastric (SCIA/SIEA) flaps for head and neck reconstruction. This was their first choice over other free flaps due to its versatile advantages. Fifteen patients underwent head and neck reconstruction with free SCIA/SIEA flaps (n = 16). No flap loss was observed; however, emergency vascular reanastomosis was performed in 3 cases to restore the blood supply in compromised flaps. Flap thinning and secondary debulking procedures were performed in 4 cases. The functional and aesthetic results were deemed as acceptable in all patients. Based on our results, we believe that the free SCIA/SIEA flap is useful for soft tissue defect reconstruction in the head and neck. It has the following advantages: (1) Large flap elevation is possible for reaching distant recipient vessels, (2) Two surgical teams may work at the same time preparing the donor and recipient regions, and (3) The flap design uses an abdominoplasty incision, which has minimal donor site morbidity.

  9. Calculation of the longitudinal aerodynamic characteristics of upper-surface-blown wing-flap configurations

    NASA Technical Reports Server (NTRS)

    Mendenhall, M. R.; Spangler, S. B.

    1978-01-01

    An engineering method for predicting the longitudinal aerodynamic characteristics of wing-flap configurations with upper surface blowing (USB) was developed. Potential flow models were incorporated into the prediction method: a wing and flap lifting surface model and a jet wake model. The wing-flap model used a vortex-lattice to represent the wing and flaps. The wing had an arbitrary planform and camber and twist, and the flap system was made up of a Coanda flap and other flap segments of arbitrary size. The jet wake model consisted of a series of closely spaced rectangular vortex rings. The wake was positioned such that it was tangent to the upper surface of the wing and flap between the exhaust nozzle and the flap trailing edge. It was specified such that the mass, momentum, and spreading rates were similar to actual USB jet wakes. Comparisons of measured and predicted pressure distributions, span load distributions, and total lift and pitching-moment coefficients on swept and unswept USB configurations are included. A wide range of thrust coefficients and flap deflection angles were considered at angles of attack up to the onset of stall.

  10. Development of an Extracorporeal Perfusion Device for Small Animal Free Flaps

    PubMed Central

    Fichter, Andreas M.; Ritschl, Lucas M.; Borgmann, Anna; Humbs, Martin; Luppa, Peter B.; Wolff, Klaus-Dietrich; Mücke, Thomas

    2016-01-01

    Background Extracorporeal perfusion (ECP) might prolong the vital storage capabilities of composite free flaps, potentially opening a wide range of clinical applications. Aim of the study was the development a validated low-cost extracorporeal perfusion model for further research in small animal free flaps. Methods After establishing optimal perfusion settings, a specially designed extracorporeal perfusion system was evaluated during 8-hour perfusion of rat epigastric flaps followed by microvascular free flap transfer. Controls comprised sham-operation, ischemia and in vivo perfusion. Flaps and perfusate (diluted blood) were closely monitored by blood gas analysis, combined laser Doppler flowmetry and remission spectroscopy and Indocyanine-Green angiography. Evaluations were complemented by assessment of necrotic area and light microscopy at day 7. Results ECP was established and maintained for 8 hours with constant potassium and pH levels. Subsequent flap transfer was successful. Notably, the rate of necrosis of extracorporeally perfused flaps (27%) was even lower than after in vivo perfusion (49%), although not statistically significant (P = 0,083). After sham-operation, only 6% of the total flap area became necrotic, while 8-hour ischemia led to total flap loss (98%). Angiographic and histological findings confirmed these observations. Conclusions Vital storage capabilities of microvascular flaps can be prolonged by temporary ECP. Our study provides important insights on the pathophysiological processes during extracorporeal tissue perfusion and provides a validated small animal perfusion model for further studies. PMID:26808996

  11. A performance application study of a jet-flap helicopter rotor

    NASA Technical Reports Server (NTRS)

    Sullivan, R. J.; Laforge, S.; Holchin, B. W.

    1972-01-01

    A performance study was made of the application of a jet-flap to a reaction-drive rotor for a heavy-lift helicopter mission and for a high-speed-helicopter maneuverability (200 knots, 2g) mission. The results of the study are as follows: As a result of the increase in maximum airfoil lift coefficient achieved by the jet-flap, rotor solidity is reduced with the jet-flap to approximately 59% of a nonjet-flap rotor. As a result of the saving in rotor solidity, and hence in rotor weight, the jet-flap configuration had a 21% higher productivity than a nonjet-flap configuration. Of the three propulsion systems studied utilizing a jet-flap (hot cycle, warm cycle, cold cycle) the hot cycle gave the largest increase in productivity. The 200 knot 2g mission is performed best with a warm cycle propulsion system. The jet-flap permits designing for a rotor blade loading coefficient C sub T/sigma = .170 at 2g without encountering blade stall. The jet-flap rotor permits a 200 knot 2g maneuver without suffering the penalty of an unreasonable rotor solidity that would be required by a nonjet-flap rotor.

  12. Improved technique for evaluating oral free flaps by pinprick testing assisted by indocyanine green near-infrared fluorescence angiography.

    PubMed

    Nagata, Tetsuji; Masumoto, Kazuma; Uchiyama, Yoshiyuki; Watanabe, Yoshiko; Azuma, Ryuichi; Morimoto, Yuji; Katou, Fuminori

    2014-10-01

    In head and neck surgery, free-flap reconstruction using a microvascular anastomosis is an indispensable option after tumor ablation. Because the success of free-flap reconstruction is enhanced by rapid identification and salvage of failing flaps, postoperative monitoring of free flaps is essential. We describe a new technique using indocyanine green (ICG) near-infrared angiography and pinprick testing to monitor intraoral free flaps. A solution of ICG (Diagnogreen, 5 ml) was intravenously injected, and scanning was performed with a near-infrared video camera system. Thirty seconds after ICG injection, a pinprick test was performed by placing a 24-gage needle through the dermis to the subcutaneous fat of the flap. Pinprick testing during ICG fluorescence imaging was performed in 30 patients. Flap perfusion was confirmed in all patients, and all flaps survived postoperatively. ICG fluorescence imaging demonstrated that flap perfusion was maintained.

  13. Modeling of flap endonuclease interactions with DNA substrate.

    PubMed

    Allawi, Hatim T; Kaiser, Michael W; Onufriev, Alexey V; Ma, Wu-Po; Brogaard, Andrew E; Case, David A; Neri, Bruce P; Lyamichev, Victor I

    2003-05-01

    Structure-specific 5' nucleases play an important role in DNA replication and repair uniquely recognizing an overlap flap DNA substrate and processing it into a DNA nick. However, in the absence of a high-resolution structure of the enzyme/DNA complex, the mechanism underlying this recognition and substrate specificity, which is key to the enzyme's function, remains unclear. Here, we propose a three-dimensional model of the structure-specific 5' flap endonuclease from Pyrococcus furiosus in its complex with DNA. The model is based on the known X-ray structure of the enzyme and a variety of biochemical and molecular dynamics (MD) data utilized in the form of distance restraints between the enzyme and the DNA. Contacts between the 5' flap endonuclease and the sugar-phosphate backbone of the overlap flap substrate were identified using enzyme activity assays on substrates with methylphosphonate or 2'-O-methyl substitutions. The enzyme footprint extends two to four base-pairs upstream and eight to nine base-pairs downstream of the cleavage site, thus covering 10-13 base-pairs of duplex DNA. The footprint data are consistent with a model in which the substrate is bound in the DNA-binding groove such that the downstream duplex interacts with the helix-hairpin-helix motif of the enzyme. MD simulations to identify the substrate orientation in this model are consistent with the results of the enzyme activity assays on the methylphosphonate and 2'-O-methyl-modified substrates. To further refine the model, 5' flap endonuclease variants with alanine point substitutions at amino acid residues expected to contact phosphates in the substrate and one deletion mutant were tested in enzyme activity assays on the methylphosphonate-modified substrates. Changes in the enzyme footprint observed for two point mutants, R64A and R94A, and for the deletion mutant in the enzyme's beta(A)/beta(B) region, were interpreted as being the result of specific interactions in the enzyme/DNA complex

  14. Salvage of failed free flaps used in head and neck reconstruction

    PubMed Central

    Novakovic, Daniel; Patel, Rajan S; Goldstein, David P; Gullane, Patrick J

    2009-01-01

    Free flap success rates are in excess of 95%. Vascular occlusion (thrombosis) remains the primary reason for flap loss, with venous thrombosis being more common than arterial occlusion. The majority of flap failures occur within the first 48 hours. With early recognition and intervention of flap compromise salvage is possible. Successful salvage rates range from 28% to over 90%. Rapid re-exploration in this clinical setting is crucial to maximise the chances of flap salvage. If salvage is not feasible or unsuccessful then non-surgical methods of salvage may be employed with some possibility of success. The purpose of this article is to review the causes of free flap failure and to highlight the available options for salvage. PMID:19698095

  15. Localized, Non-Harmonic Active Flap Motions for Low Frequency In-Plane Rotor Noise Reduction

    NASA Technical Reports Server (NTRS)

    Sim, Ben W.; Potsdam, Mark; Kitaplioglu, Cahit; LeMasurier, Philip; Lorber, Peter; Andrews, Joseph

    2012-01-01

    A first-of-its-kind demonstration of the use of localized, non-harmonic active flap motions, for suppressing low frequency, in-plane rotor noise, is reported in this paper. Operational feasibility is verified via testing of the full-scale AATD/Sikorsky/UTRC active flap demonstration rotor in the NFAC's 40- by 80-Foot anechoic wind tunnel. Effectiveness of using localized, non-harmonic active flap motions are compared to conventional four-per-rev harmonic flap motions, and also active flap motions derived from closed-loop acoustics implementations. All three approaches resulted in approximately the same noise reductions over an in-plane three-by-three microphone array installed forward and near in-plane of the rotor in the nearfield. It is also reported that using an active flap in this localized, non-harmonic manner, resulted in no more that 2% rotor performance penalty, but had the tendency to incur higher hub vibration levels.

  16. Flap survey test of a combined surface blowing model: Flow measurements at static flow conditions

    NASA Technical Reports Server (NTRS)

    Fukushima, T.

    1978-01-01

    The Combined Surface Blowing (CSB) V/STOL lift/propulsion system consists of a blown flap system which deflects the exhaust from a turbojet engine over a system of flaps deployed at the trailing edge of the wing. Flow measurements consisting of velocity measurements using split film probes and total measure surveys using a miniature Kiel probe were made at control stations along the flap systems at two spanwise stations, the centerline of the nozzle and 60 percent of the nozzle span outboard of the centerline. Surface pressure measurements were made in the wing cove and the upper surface of the first flap element. The test showed a significant flow separation in the wing cove. The extent of the separation is so large that the flow into the first flap takes place only at the leading edge of the flap. The velocity profile measurements indicate that large spanwise (3 dimensional) flow may exist.

  17. [The role definition of lateral arm free flap in reconstruction after head and neck cancer surgery].

    PubMed

    Li, C; Cai, Y C; Wang, W; He, Y X; Lan, X J; Li, Q L; Zhou, Y Q; Liu, J F; Zhu, G Q; Liu, K; Wang, S X; Wang, K; Fan, J C; Sun, R H

    2016-02-01

    Application of free flap is one of the important repair means in head and neck surgery. A variety of free flaps, such as anterolateral thigh flap, have showed unique advantages in repair for tissue defects after resection of head and neck tumor, and have became increasing popularity. Lateral arm flee flap is an important repair means in plastic surgery, which has developed more than 30 years, but the application of this flap for reconstruction in head and neck surgery is relatively backward, with few reports. This review focuses on the creativity and innovation, the relationship between anatomy and clinical application, and the application status and prospects for lateral arm flee flap in individual head and neck reconstruction surgery.

  18. The superior gluteal artery perforator flap for reconstruction of sacral sores

    PubMed Central

    Chen, Weijian; Jiang, Bo; Zhao, Jiaju; Wang, Peiji

    2016-01-01

    This report describes our experiences using the superior gluteal artery perforator (SGAP) flaps for reconstruction of 2 sacral sore cases. A 47-year-old female patient and a 38-year-old man with sacral sores were treated in our unit. The size of the defects were approximately 5×6 cm2 and 8×9 cm2, the defects were repaired by SGAP flaps. The size of designed was SGAP flaps varied from 7×20 to 9×16 cm2. All flaps survived and healed primary, the texture, functions, and appearance of flaps were satisfactory, and also without region dysfunction of donor and recipient sites. The SGAP flap, which has reliable blood supply, preserves the gluteus maximus muscle and could be transferred simply and safely, is an ideal and reusable method to reconstruct sacral sores with low rate of postoperative recurrence and satisfactory appearance. PMID:27652367

  19. [Harvesting technique of chimeric multiple paddles fibular flap for wide oromandibular defects].

    PubMed

    Foy, J-P; Qassemyar, Q; Assouly, N; Temam, S; Kolb, F

    2016-08-01

    Carcinological head and neck reconstruction still remains a challenge due to the volume and varied tissues needed. Large and wide oromandibular defects require, not just the bone but also soft tissues for the pelvilingual reconstruction and therefore, a second free flap may become necessary in addition to a fibular flap. The option of an unique chimeric flap based on the fibular artery and its branches is less known whereas it offers the advantage of a unique flap with bone, muscle and multiple skin paddles, independent of each other. The aim of this technical note is to present step by step the surgical procedure of this chimeric flap and share this method that avoids a second free flap.

  20. Analysis of a Multi-Flap Control System for a Swashplateless Rotor

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Wilbur, Matthew L.

    2011-01-01

    An analytical study was conducted examining the feasibility of a swashplateless rotor controlled through two trailing edge flaps (TEF), where the cyclic and collective controls were provided by separate TEFs. This analysis included a parametric study examining the impact of various design parameters on TEF deflections. Blade pitch bearing stiffness; blade pitch index; and flap chord, span, location, and control function of the inboard and outboard flaps were systematically varied on a utility-class rotorcraft trimmed in steady level flight. Gradient-based optimizations minimizing flap deflections were performed to identify single- and two-TEF swashplateless rotor designs. Steady, forward and turning flight analyses suggest that a two-TEF swashplateless rotor where the outboard flap provides cyclic control and inboard flap provides collective control can reduce TEF deflection requirements without a significant impact on power, compared to a single-TEF swashplateless rotor design.

  1. The superior gluteal artery perforator flap for reconstruction of sacral sores.

    PubMed

    Chen, Weijian; Jiang, Bo; Zhao, Jiaju; Wang, Peiji

    2016-10-01

    This report describes our experiences using the superior gluteal artery perforator (SGAP) flaps for reconstruction of 2 sacral sore cases. A 47-year-old female patient and a  38-year-old man with sacral sores were treated in our unit. The size of the defects were approximately 5×6 cm2  and 8×9 cm2, the  defects were repaired by SGAP flaps. The size of designed was  SGAP flaps varied from  7×20 to 9×16 cm2. All flaps survived and healed primary, the texture, functions, and appearance of flaps were satisfactory, and also without region dysfunction of donor and recipient sites. The SGAP flap, which has reliable blood supply,  preserves the gluteus maximus muscle and could be transferred simply and safely, is an ideal and reusable method to reconstruct sacral sores with low rate of postoperative recurrence and satisfactory appearance. PMID:27652367

  2. Current sheet flapping motions in the tailward flow of magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Wu, Mingyu; Lu, Quanming; Volwerk, Martin; Vörös, Zoltán.; Ma, Xuanye; Wang, Shui

    2016-08-01

    The feature and origin of current sheet flapping motions are one of most interesting issues of magnetospheric dynamics. In this paper we report the flapping motion of the current sheet detected in the tailward flow of a magnetic reconnection event on 7 February 2009. This flapping motion with frequency about 12 mHz was accompanied by magnetic turbulence. The observations by the tail-elongated fleet of five Time History of Events and Macroscale Interactions during Substorms probes indicate that these flapping oscillations were rather confined within the tailward flow than were due to a global process. This flapping motion could be due to the instability driven by the free energy associated with the ion temperature anisotropy in the tailward flow. Our observations indicate that the flapping motion in the tailward flow could have a different generation mechanism with that in the earthward flow.

  3. Versatility of Abbe-Estlander Flap in Lip Reconstruction – A Prospective Clinical Study

    PubMed Central

    Shetty, Premlatha M; Bhambar, Rohan Suhas; Gattumeedhi, Shashank Redddy; Kumar, Ram Mohan; Kumar, Harsh

    2014-01-01

    Aims & Objectives: Aim of this study was to evaluate the versatility of Abbe-Estlander flap in lip reconstruction with regard to function and aesthetic outcome and objectives were to present our experience and result in series of 10 cases of lip reconstruction by Abbe-Estlander flap. Materials and Methods: A total number of 10 patients were taken up in the study, age ranging from 35-71 y, mean age being 60. Out of 10 patients, 6 (60%) were male and 4 (40%) female. In all these patients, Abbe-Estlander flap that involved the commissure was used for reconstruction. Patients were recalled at intervals of three weeks, three months and six months for follow up. Results: All patients had satisfactory results in terms of aesthetic and functional outcome. Conclusion: Abbe-Estlander flap is safe and a reliable flap which is technically simple to perform, and provides functionally and aesthetically pleasing result and affords versatility in flap design. PMID:25478393

  4. Perforator-based chimaeric thoracodorsal flap for foot reconstruction.

    PubMed

    Rausky, Jonathan; Binder, Jean-Philippe; Mazouz-Dorval, Sarra; Hamou, Cynthia; Revol, Marc

    2013-12-01

    The reconstruction of severe defects of the ankle and foot is a challenge. The ideal solution should combine a thin skin flap on the dorsum to allow shoe fitting and a muscle flap with a split-thickness skin graft on the weight-bearing area. Perforator-based thoracodorsal chimaeric flaps allow us to achieve these two goals with minimal donor-site morbidity. We present a reconstruction of an extended circumferential defect of the ankle with an exposed heel using a chimaeric thoracodorsal perforator flap with a serratus muscle flap. The skin flap was transferred on the dorsal foot, whereas the serratus anterior muscle was transferred on the exposed heel. Postoperative recovery was uneventful and the patient began full weight bearing after 3 months. Twelve months after reconstruction, natural shape and walking function were successfully achieved.

  5. Wind-tunnel investigation of a Fowler flap and spoiler for an advanced general aviation wing

    NASA Technical Reports Server (NTRS)

    Paulson, J. W., Jr.

    1976-01-01

    The wing was tested without fuselage or empennage and was fitted with approximately three-quarter span Fowler flaps and half span spoilers. The spoilers were hinged at the 70 percent chord point and vented when the flaps were deflected. Static longitudinal and lateral aerodynamic data were obtained over an angle of attack range of -8 deg to 22 deg for various flap deflections and positions, spoiler geometries, and vent lip geometries. Lateral characteristics indicate that the spoilers are generally adequate for lateral control. In general, the spoiler effectiveness increases with increasing angle of attack, increases with increasing flap deflections, and is influenced by vent lip geometry. In addition, the data show that some two-dimensional effects on spoiler effectiveness are reduced in the three-dimensional case. Results also indicate significant increase in lift coefficient as the Fowler flaps are deflected; when the flap was fully deflected, the maximum wing lift coefficient was increased about 96 percent.

  6. Magnetostrictively actuated control flaps for vibration reduction in helicopter rotors

    SciTech Connect

    Millott, T.; Friedmann, P.P.

    1994-12-31

    High vibration levels can impose constraints on helicopter operations and hinder passenger acceptance. Vibration reduction using blade root pitch control introduces a significant power penalty and may adversely affect the airworthiness of the flight control system. Comparable levels of vibration reduction can be achieved using considerably less power through an actively controlled trailing edge flap mounted on the blade. Such a device would have no effect on helicopter airworthiness since it is controlled by a loop separate from the primary flight control system which utilizes the swashplate. Control flap actuation using the magnetostrictive material Terfenol-D is studied in this paper by designing a minimum weight actuator, subject to a set of actuation and stress constraints. The resulting device is capable of producing vibration reduction in excess of 90% at cruise conditions.

  7. Destabilization of flapping sheets: The surprising analogue of soap films

    NASA Astrophysics Data System (ADS)

    Lhuissier, H.; Villermaux, E.

    2009-06-01

    When punctured, a uniform liquid sheet is known, since Taylor and Culick, to recess at a constant speed, balancing surface tension and inertia. For planar soap films, this steady solution holds until the initially smooth receding rim is violently destabilized, exhibiting deep indentations from which droplets are ejected. A surprising new three-dimensional mechanism explaining this destabilization and resulting wavelength has been demonstrated: because of the shear between the still outer medium and the receding liquid, the film flaps through a Kelvin-Helmholtz instability, itself inducing an acceleration perpendicular to the film, which intensifies with the flapping amplitude. To this acceleration is associated a classical Rayleigh-Taylor mechanism, promoting the rim indentations. To cite this article: H. Lhuissier, E. Villermaux, C. R. Mecanique 337 (2009).

  8. Development of the space shuttle body flap actuation subsystem

    NASA Technical Reports Server (NTRS)

    Boggs, C. R.

    1985-01-01

    Development of the Body Flap Actuation Subsystem for Space Shuttles included alterations from the original design to mechanical stops, planet gears, control valves, and solenoid valves. The mechanical stops were redesigned to absorb stall load and rotating inertia of the hydraulic motors instead of only stall load. The institution of a quill shaft (torsion spring) was a successful solution. The planet gears in the geared rotary actuators developed cracks during testing. This failure was alleviated via modification to the gears. A motor pressurization - brake release timing technique was developed thru analysis and testing. This resulted in a control valve configuration which would not permit freewheeling of the body flap surface. Finally, several solenoid valve configurations were tested to obtain the desired performance. Conceptual redesigns and modifications were weighted against each other to optimize a solution. Tradeoffs were usually made between life, performance, failure tolerance, and reliability versus weight, envelope, and maintainability.

  9. Ontogeny of aerial righting and wing flapping in juvenile birds.

    PubMed

    Evangelista, Dennis; Cam, Sharlene; Huynh, Tony; Krivitskiy, Igor; Dudley, Robert

    2014-08-01

    Mechanisms of aerial righting in juvenile chukar partridge (Alectoris chukar) were studied from hatching to 14 days-post-hatching (dph). Asymmetric movements of the wings were used from 1 to 8 dph to effect progressively more successful righting behaviour via body roll. Following 8 dph, wing motions transitioned to bilaterally symmetric flapping that yielded aerial righting via nose-down pitch, along with substantial increases in vertical force production during descent. Ontogenetically, the use of such wing motions to effect aerial righting precedes both symmetric flapping and a previously documented behaviour in chukar (i.e. wing-assisted incline running) hypothesized to be relevant to incipient flight evolution in birds. These findings highlight the importance of asymmetric wing activation and controlled aerial manoeuvres during bird development and are potentially relevant to understanding the origins of avian flight. PMID:25165451

  10. Inclusion of nonlinear aerodynamics in the FLAP code

    SciTech Connect

    Weber, T

    1989-11-01

    Horizontal axis wind turbines usually operate with significant portions of the blade in deep stall. This contradicts the assumption in the FLAP code that a linear relation exists between the angle of attack and the lift coefficient. The objective of this paper is to determine the importance of nonlinear aerodynamics in the prediction of loads. The FLAP code has been modified to include the nonlinear relationships between the lift and drag coefficients with the angle of attack. The modification affects the calculation of the induced velocities and the aerodynamic loads. This requires an iterative procedure to determine the induced velocities instead of a closed form solution. A more advanced tower interference model has also been added that accounts for both upwind and downwind tower effects. 7 refs., 14 figs.

  11. The X-38 V-201 Flap Actuator Mechanism

    NASA Technical Reports Server (NTRS)

    Hagen, Jeff; Moore, Landon; Estes, Jay; Layer, Chris

    2004-01-01

    The X-38 Crew Rescue Vehicle V-201 space flight test article was designed to achieve an aerodynamically controlled re-entry from orbit in part through the use of two body mounted flaps on the lower rear side. These flaps are actuated by an electromechanical system that is partially exposed to the re-entry environment. These actuators are of a novel configuration and are unique in their requirement to function while exposed to re-entry conditions. The authors are not aware of any other vehicle in which a major actuator system was required to function throughout the complete re-entry profile while parts of the actuator were directly exposed to the ambient environment.

  12. Nonlinear flap-lag axial equations of a rotating beam

    NASA Technical Reports Server (NTRS)

    Kaza, K. R. V.; Kvaternik, R. G.

    1977-01-01

    It is possible to identify essentially four approaches by which analysts have established either the linear or nonlinear governing equations of motion for a particular problem related to the dynamics of rotating elastic bodies. The approaches include the effective applied load artifice in combination with a variational principle and the use of Newton's second law, written as D'Alembert's principle, applied to the deformed configuration. A third approach is a variational method in which nonlinear strain-displacement relations and a first-degree displacement field are used. The method introduced by Vigneron (1975) for deriving the linear flap-lag equations of a rotating beam constitutes the fourth approach. The reported investigation shows that all four approaches make use of the geometric nonlinear theory of elasticity. An alternative method for deriving the nonlinear coupled flap-lag-axial equations of motion is also discussed.

  13. Flap-Lag-Torsion Stability in Forward Flight

    NASA Technical Reports Server (NTRS)

    Panda, B.; Chopra, I.

    1985-01-01

    An aeroelastic stability of three-degree flap-lag-torsion blade in forward flight is examined. Quasisteady aerodynamics with a dynamic inflow model is used. The nonlinear time dependent periodic blade response is calculated using an iterative procedure based on Floquet theory. The periodic perturbation equations are solved for stability using Floquet transition matrix theory as well as constant coefficient approximation in the fixed reference frame. Results are presented for both stiff-inplane and soft-inplane blade configurations. The effects of several parameters on blade stability are examined, including structural coupling, pitch-flap and pitch-lag coupling, torsion stiffness, steady inflow distribution, dynamic inflow, blade response solution and constant coefficient approximation.

  14. Tertiary resurfacing after one of the first free flaps in Europe, a reflection on 30 years of microsurgical progress.

    PubMed

    Hart, A M; Tollan, C J; Dabernig, J; Acland, R; Taggart, I

    2007-01-01

    Free flaps have been used for over 30 years. During this period, improved anatomical understanding has increased donor options and available pedicle lengths, permitting safer, single-stage reconstructions with simpler anastomoses. Refinements, such as perforator flaps in particular, have greatly improved donor morbidity, recipient site cosmesis, and the ability to replace 'like with like' while retaining options for innervation. This case highlights the evolution from one of Europe's first free tissue transfers, effectively a perforator flap, through the advent of free muscle flaps to the current generation of contourable perforator flaps. Free flap transfer has become increasingly sophisticated, safer, and more predictable, yet the potential quality of reconstructive outcome has changed little.

  15. Outcomes of Take-Back Operations in Breast Reconstruction with Free Lower Abdominal Flaps

    PubMed Central

    Yim, Ji Hong; Yun, Jiyoung; Lee, Taik Jong; Kim, Eun Key; Cho, Jonghan

    2015-01-01

    Background Microvascular complications after free-flap breast reconstructions are potentially devastating problems that can increase patient morbidity and lead to flap loss. To date, no comprehensive study has examined the rates of salvage and the methods of microvascular revision in breast reconstruction. We reviewed the treatment of microvascular complications of free-flap breast reconstruction procedures over a seven-year period. Methods A retrospective review of all patients who underwent microvascular breast reconstruction at our institution between April 2006 and December 2013 was conducted. Based on their surgical records, all patients who required emergency re-exploration were identified, the rate of flap salvage was determined, the factors associated with flap salvage were evaluated, and the causes and methods of revision were reviewed. Results During the review period, 605 breast reconstruction procedures with a free lower abdominal flap were performed. Seventeen of these flaps were compromised by microvascular complications, and three flaps were lost. The overall salvage rate was 82.35%. No significant differences between the salvaged group and the failed group were observed with regard to age, BMI, axillary dissection, number of anastomotic arteries and veins, recipient vessel types, or use of the superficial inferior epigastric vein in the revision operation. Successful salvage of the flap was associated with a shorter time period between recognizing the signs of flap compromise and the take-back operation. Conclusions The salvage rate of compromised lower abdominal flaps was high enough to warrant attempting re-exploration. Immediate intervention after the onset of flap compromise signs is as important as vigilant postoperative monitoring. PMID:26618122

  16. A standardized model for predicting flap failure using indocyanine green dye

    NASA Astrophysics Data System (ADS)

    Zimmermann, Terence M.; Moore, Lindsay S.; Warram, Jason M.; Greene, Benjamin J.; Nakhmani, Arie; Korb, Melissa L.; Rosenthal, Eben L.

    2016-03-01

    Techniques that provide a non-invasive method for evaluation of intraoperative skin flap perfusion are currently available but underutilized. We hypothesize that intraoperative vascular imaging can be used to reliably assess skin flap perfusion and elucidate areas of future necrosis by means of a standardized critical perfusion threshold. Five animal groups (negative controls, n=4; positive controls, n=5; chemotherapy group, n=5; radiation group, n=5; chemoradiation group, n=5) underwent pre-flap treatments two weeks prior to undergoing random pattern dorsal fasciocutaneous flaps with a length to width ratio of 2:1 (3 x 1.5 cm). Flap perfusion was assessed via laser-assisted indocyanine green dye angiography and compared to standard clinical assessment for predictive accuracy of flap necrosis. For estimating flap-failure, clinical prediction achieved a sensitivity of 79.3% and a specificity of 90.5%. When average flap perfusion was more than three standard deviations below the average flap perfusion for the negative control group at the time of the flap procedure (144.3+/-17.05 absolute perfusion units), laser-assisted indocyanine green dye angiography achieved a sensitivity of 81.1% and a specificity of 97.3%. When absolute perfusion units were seven standard deviations below the average flap perfusion for the negative control group, specificity of necrosis prediction was 100%. Quantitative absolute perfusion units can improve specificity for intraoperative prediction of viable tissue. Using this strategy, a positive predictive threshold of flap failure can be standardized for clinical use.

  17. Noise Radiation from a Continuous Mold-Line Link Flap Configuration

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Brooks, Thomas F.; Humphreys, William M.

    2008-01-01

    The results of an experimental study of the noise from a Continuous Mold-Line Link (CML) flap are presented. Acoustic and unsteady surface pressure measurements were performed on a main element wing section with a half-span CML flap in NASA Langley s Quiet Flow Facility. The acoustic data were acquired with a medium aperture directional array (MADA) of microphones. The Deconvolution Approach for the Mapping of Acoustic Sources (DAMAS) method is applied to determine the spatial distribution and strength of the noise sources over the surface of the test model. A Coherent Output Power (COP) method which relates the output from unsteady surface pressure sensors to the output of the MADA is also used to obtain more detailed characteristics of the noise source distribution in the trailing edge region of the CML. These results are compared to those obtained for a blunt flap to quantify the level of noise benefit that is achieved with the CML flap. The results indicate that the noise from the CML region of the flap is 5 to 17 dB lower (depending on flap deflection and Mach number) than the noise from the side edge region of the blunt flap. Lower noise levels are obtained for all frequencies. Spectral analysis of the noise from the cove region of the CML and blunt flap models also reveal a spectral peak in the high frequency range that is related to noise scattering at the trailing edge of the main element. The peaks in the CML and blunt flap cove noise spectra are close in level and often exceed blunt side edge noise. Applying a strip of serrated tape to the trailing edge of the CML flap model main airfoil, reduced the peak but increased other noise somewhat. Directivity measurements show that the CML flap can be more directional than the blunt flap.

  18. Noise Radiation from a Continuous Mold-Line Link Flap Configuration

    NASA Technical Reports Server (NTRS)

    Hutcheson, Florence V.; Brooks, Thomas F.; Humphreys, William M., Jr.

    2011-01-01

    The results of an experimental study of the noise from a Continuous Mold-Line Link (CML) flap are presented. Acoustic and unsteady surface pressure measurements were performed on a main element wing section with a half-span CML flap in NASA Langley s Quiet Flow Facility. The acoustic data were acquired with a medium aperture directional array (MADA) of microphones. The Deconvolution Approach for the Mapping of Acoustic Sources (DAMAS) method is applied to determine the spatial distribution and strength of the noise sources over the surface of the test model. A Coherent Output Power (COP) method which relates the output from unsteady surface pressure sensors to the output of the MADA is also used to obtain more detailed characteristics of the noise source distribution in the trailing edge region of the CML. These results are compared to those obtained for a blunt flap to quantify the level of noise benefit that is achieved with the CML flap. The results indicate that the noise from the CML region of the flap is 5 to 17 dB lower (depending on flap deflection and Mach number) than the noise from the side edge region of the blunt flap. Lower noise levels are obtained for all frequencies. Spectral analysis of the noise from the cove region of the CML and blunt flap models also reveal a spectral peak in the high frequency range that is related to noise scattering at the trailing edge of the main element. The peaks in the CML and blunt flap cove noise spectra are close in level and often exceed blunt side edge noise. Applying a strip of serrated tape to the trailing edge of the CML flap model main airfoil reduced the peak but increased other noise somewhat. Directivity measurements show that the CML flap can be more directional than the blunt flap.

  19. Inferiorly based thigh flap for reconstruction of defects around the knee joint

    PubMed Central

    Akhtar, Md. Sohaib; Khan, Arshad Hafeez; Khurram, Mohammed Fahud; Ahmad, Imran

    2014-01-01

    Background: Soft-tissue defects around the knees are common in injured limbs and in the same injury the leg is often involved and the thigh is spared. Furthermore due to pliable and relatively lax skin, we have used inferiorly based thigh flap to reconstruct defects around knee joint. Aims and Objectives: The aim of this study is to evaluate the use of inferiorly based thigh flap to cover soft-tissue defects over the proximal one-third of the leg, patellar region, knee, and lower thigh. Materials and Methods: This study was conducted during the period between October 2011 and February 2013. Inferiorly based anteromedial thigh fasciocutaneous flap was performed on 12 patients and inferiorly based anterolateral thigh fasciocutaneous flap on four patients. The sites of the soft-tissue defects included patellar regions, infrapatellar region, upper one-third of leg, lower thigh, and over the knee joint. Results: Patients were evaluated post-operatively in terms of viability of flap, the matching of the flap with the recipient site, and donor site morbidity. All the flaps survived well except one which developed distal marginal flap loss, one in which wound dehiscence was noticed, and two in which mild venous congestion was observed. Venous congestion in two patients subsided on its own within 3 days. One patient with wound dehiscence achieved complete healing by secondary intention. Patient who developed distal flap loss required debridement and skin grafting. No appreciable donor site morbidity was encountered. Skin colour and texture of the flap matched well with the recipient site. Conclusions: The inferiorly based thigh flap is a reliable flap to cover the defect over proximal one-third of the leg, patellar region, knee, and lower thigh. PMID:25190918

  20. Microcapillary sign of flap alignment in femtosecond laser-assisted in situ keratomileusis

    PubMed Central

    Fawzy, Fathy; Wahba, Sherine S; Fawzy, Nader

    2016-01-01

    We present an observational sign that ensures perfect alignment during femtosecond laser-assisted in situ keratomileusis (FS LASIK). Alignment is assured when a microsponge is used to dry the flap and the area of dryness exceeds the area of direct touch of the microsponge. The area might even reach the whole circumference of the flap at the first touch. This sign of alignment can be explained by microcapillary action. This sign was not elicited in flaps created by a microkeratome. PMID:27799731

  1. Immediate use of medicinal leeches to salvage venous congested reverse pedicled neurocutaneous flaps.

    PubMed

    Gideroglu, Kaan; Yildirim, Serkan; Akan, Mithat; Akoz, Tayfun

    2003-01-01

    Reverse pedicled neurocutaneous flaps have recently become popular for reconstructing soft tissue defects of the lower extremity. Venous congestion is a relatively common problem in these flaps in diabetic patients and those with electric burns, and this may cause partial or complete loss if capillary perfusion is not re-established urgently. We describe our experience of 13 neurocutaneous flaps, of which five developed venous congestion and were treated successfully with leeches placed immediately.

  2. Super-Drained Distally Based Neurofasciocutaneous Sural Flap: A Case Series and Review of Literature

    PubMed Central

    El-Diwany, Mostafa; Karunanayake, Mihiran; Al-Mutari, Sultan; Duvernay, Alain

    2015-01-01

    Objective: The distally based neurofasciocutaneous sural flap is central to the armamentarium for the reconstruction of leg's distal third, ankle, and hindfoot. Despite the use of adapted techniques aimed at increasing the flap's reliability, venous congestion remains a frequently encountered problem. We present a venous super-drainage technique used by the senior author to reduce venous congestion and improve flap reliability when harvesting larger flaps. Methods: A retrospective chart review, from January 2002 to October 2008, at 2 tertiary care centers, was conducted on all cases of inferior limb reconstruction with reverse sural flaps on defects greater than 10 × 5 cm. In addition, a literature review was carried out to examine the average sural flap surface area and reported complications published from 1992 to 2012. We then compared our results with those published in the literature. Results: A total of 15 flaps were identified. Mean flap dimensions were 14 × 8.5 cm (mean area = 115.27 cm2; 95% confidence interval, 99.28–131.26). None of the flaps developed complications (arterial or venous insufficiency, partial/complete necrosis). The average flap surface area in the literature is 55.08 cm2, with a 22% rate of total complications. We harvested significantly larger flaps (P < .001) with a significantly lower total complication rate (P < .05) when compared with that reported in the literature. Conclusion: Anastomosing the proximal end of the lesser saphenous vein with a vein at the defect site improves venous outflow, effectively reducing the incidence of venous congestion, increases the potential flap size, and improves reliability. PMID:25987941

  3. [Antecubital flap: advantages in elbow coverage. An anatomical study and experience of five clinical cases].

    PubMed

    Duteille, F; Rocchi, L; Dautel, G; Merle, M

    2001-02-01

    The antecubital flap is a fasciocutaneous strip that has its blood supply provided by the first proximal collateral of the radial artery. This flap was described for the first time in 1983 by Lamberty and Cormack, but it has not been widely used and there have been only a few reports in the literature concerning this procedure. The aim of the present investigation was to demonstrate via an anatomical study and a report on five cases the viability of the various anatomical features of this cutaneous flap, and also its positive contribution to elbow reconstruction. The anatomical study involved eight fresh cadavers (eight upper limbs). An injection of colored prevulcanized latex was made in the humeral artery in the lower third of the arm. The aim was to determine which artery provided blood supply to the flap, its anatomical location, and also to look for possible distal anastomoses which would permit a distal pedicled flap to be removed. Contrary to the findings of other authors, in the present study it was found that the vessel providing blood to the antecubital flap always branched off from the radial artery. However, no anastomoses with distal vascularization were detected, which would have permitted a distal pedicled flap to be obtained. The use of the antecubital flap for elbow coverage was then illustrated by five clinical cases of soft tissue defects of the elbow. This method was found to be reliable, practical, and the flap could be rapidly dissected. Moreover, this particular technique is sensitive, and has an interesting rotational arc. The distal cutaneous island flap has the advantage of limiting scar tissue. A comparison between the antecubital flap and other pedicled flaps has then been made. In conclusion, it appears that this little-known procedure has definite advantages, and that it should be included in the range of surgical techniques that are available for soft tissue reconstruction in the case of elbow defects.

  4. Flap noise and aerodynamic results for model QCSEE over-the-wing configurations

    NASA Technical Reports Server (NTRS)

    Olsen, W.; Burns, R.; Groesbeck, D. E.

    1977-01-01

    Noise spectra in three dimensions and aerodynamic data were measured for a model of the NASA quiet clean short-haul experimental engine (QCSEE) over-the-wing configuration. The effects of flap length, nozzle exhaust velocity, and nozzle geometry were determined using a single nozzle and wing-flap segment. The scaled-up model data is representative of full scale flap noise with the QCSEE engine.

  5. Self-propulsion of flapping bodies in viscous fluids: Recent advances and perspectives

    NASA Astrophysics Data System (ADS)

    Wang, Shizhao; He, Guowei; Zhang, Xing

    2016-08-01

    Flapping-powered propulsion is used by many animals to locomote through air or water. Here we review recent experimental and numerical studies on self-propelled mechanical systems powered by a flapping motion. These studies improve our understanding of the mutual interaction between actively flapping bodies and surrounding fluids. The results obtained in these works provide not only new insights into biolocomotion but also useful information for the biomimetic design of artificial flyers and swimmers.

  6. Flow structures around a flapping wing considering ground effect

    NASA Astrophysics Data System (ADS)

    Van Truong, Tien; Kim, Jihoon; Kim, Min Jun; Park, Hoon Cheol; Yoon, Kwang Joon; Byun, Doyoung

    2013-07-01

    Over the past several decades, there has been great interest in understanding the aerodynamics of flapping flight, namely the two flight modes of hovering and forward flight. However, there has been little focus on the aerodynamic characteristics during takeoff of insects. In a previous study we found that the Rhinoceros Beetle ( Trypoxylusdichotomus) takes off without jumping, which is uncommon for other insects. In this study we built a scaled-up electromechanical model of a flapping wing and investigated fluid flow around the beetle's wing model. In particular, the present dynamically scaled mechanical model has the wing kinematics pattern achieved from the real beetle's wing kinematics during takeoff. In addition, we could systematically change the three-dimensional inclined motion of the flapping model through each stroke. We used digital particle image velocimetry with high spatial resolution, and were able to qualitatively and quantitatively study the flow field around the wing at a Reynolds number of approximately 10,000. The present results provide insight into the aerodynamics and the evolution of vortical structures, as well as the ground effect experienced by a beetle's wing during takeoff. The main unsteady mechanisms of beetles have been identified and intensively analyzed as the stability of the leading edge vortex (LEV) during strokes, the delayed stall during upstroke, the rotational circulation in pronation periods, and wake capture in supination periods. Due to the ground effect, the LEV was enhanced during half downstroke, and the lift force could thus be increased to lift the beetle during takeoff. This is useful for researchers in developing a micro air vehicle that has a beetle-like flapping wing motion.

  7. Jet-Engine Exhaust Nozzle With Thrust-Directing Flaps

    NASA Technical Reports Server (NTRS)

    Wing, David J.

    1996-01-01

    Convergent/divergent jet-engine exhaust nozzle has cruciform divergent passage containing flaps that move to deflect flow of exhaust in either or both planes perpendicular to main fore-and-aft axis of undeflected flow. Prototype of thrust-vector-control nozzles installed in advanced, high-performance airplanes to provide large pitching (usually, vertical) and yawing (usually, horizontal) attitude-control forces independent of attitude-control forces produced by usual aerodynamic control surfaces.

  8. Management of postirradiation recurrent enterocutaneous fistula by muscle flaps

    SciTech Connect

    Lui, R.C.; Friedman, R.; Fleischer, A.

    1989-07-01

    Occasionally surgeons have to operate on patients who have had previous abdominal or pelvic operations and irradiations for malignancies. Bowel resection with primary anastomosis under these circumstances is fraught with major complications such as anastomotic breakdown with intra-abdominal sepsis or recurrent enterocutaneous fistula, which are refractory to conventional management. New techniques for using vascularized muscle flaps from a distant nonirradiated field to achieve safe repair of the bowel defects in three such instances are presented.

  9. Infected Median Sternotomy Wound: Successful Treatment by Muscle Flaps

    PubMed Central

    Jurkiewicz, M. J.; Bostwick, John; Hester, T. Roderick; Bishop, J. Barry; Craver, Joseph

    1980-01-01

    The purpose of this paper is to present the experience at Emory University Hospital with the infected median sternotomy wound and to offer a treatment plan for those patients recalcitrant to the usual therapy of debridement and closed catheter irrigation with antimicrobial agents. When standard treatment fails, we proceed not only with the necessary thorough debridement to convert the wound to a relatively clean one but also concomitant closure by pectoralis major muscle flaps to completely obliterate dead space. Transposition flaps of rectus abdominus muscle or omentum are used when necessary to complete the closure. In the initial phase of this study, there were 3,239 patients who underwent open heart procedures through a median sternotomy approach in the years 1975 through 1978. In the 50 patients who had wound infections (1.54%), there were nine deaths. Three were thought to be unrelated to the sternal wound infection, four patients ruptured the ventricle or aorta, two patients died of generalized sepsis. Of these 50 patients, 22 responded to simple drainage; 28 had involvement of the mediastinum (0.86%). Of the 28 patients, 25 had debridement and closed mediastinal irrigation by catheter. Fourteen of these 25 did not respond. In these failing patients, 12 were treated by further debridement and closure by muscle flaps. Nine of these 12 were rescued. In the past nine months, an additional 1,052 patients had an open heart procedure. Of these, 11 had a median sternotomy infection. There have been no deaths in this latter group of patients, most of whom were treated by the muscle flap procedure. In addition to the improvement in mortality, morbidity has been reduced substantially. This procedure provides for a rational approach that we have found to permit salvage of a high percentage of patients who failed conventional closed irrigation techniques. ImagesFig. 1.Figs. 2a and b.Fig. 3(a).Fig. 4.Fig. 5. PMID:7387236

  10. The role of free flap reconstruction in paediatric caustic burns.

    PubMed

    Sadiq, Zaid; Farook, Shahme A; Ayliffe, Peter

    2013-09-01

    Ingestion of caustic soda can cause severe scarring of the oral cavity and the surrounding soft tissues. Free flap reconstruction for burns in the oral cavity has been described as a viable option in adults, but to the best of our knowledge has not been reported in children. We describe cases of successful microvascular reconstruction for burns caused by caustic soda in the oral cavity in children.

  11. Vascularised local and free flaps in anterior skull base reconstruction.

    PubMed

    Hoffmann, Thomas K; El Hindy, Nicolai; Müller, Oliver M; Schuler, Patrick J; Bergmann, Christoph; Hierner, Robert; Lehnerdt, Götz; Mattheis, Stefan; Wagenmann, Martin; Schipper, Jörg; Sure, Ulrich; Lang, Stephan; Hänggi, Daniel; Sandalcioglu, I Erol

    2013-03-01

    Lesions of the anterior skull base often require sufficient closure in order to prevent cerebrospinal fluid (CSF) leak, ascending infection and/or brain tissue prolapse. The transfer of devitalized autologous, allogenic or xenogeneic material is not always sufficient particularly not in larger defects or in the recurrent situation. Here the transfer of vascularised tissue seems to be more appropriate. The anterior skull base with various complex defects of 41 patients was reconstructed in an interdisciplinary setting by vascularised, autologous tissue transfer. Minor defects (<2.5 cm in max. diameter), generally occurring after extended endoscopic skull base approaches (n = 26, among those meningiomas, recurrent CSF fistulas, chordoma, chondroblastoma, metastasis, nasal fistula), were reconstructed by a local, vascularized pedicled mucosal flap of the lower turbinate (n = 3) or septum (n = 23). Patients with major defects (>2.5 cm in max. diameter, n = 15), comprising those with malignoma, meningoencephalocele, aneurysmatic bone cyst and trauma, were repaired by a "sandwich technique" with a combination of calvarian split and galea periosteum flap in 10 patients, in one case with a temporalis muscle flap, while in 4 further patients free vascularised radial forearm flaps were used for revision after multiple unsuccessful operations elsewhere. After a mean follow-up time of 30.5 months 38 of the 41 cases were successfully repaired with respect to prevention and treatment of CSF leakage or brain tissue prolapse, only 3 cases needed surgical revision. The reconstruction of the anterior skull base bearing complex lesions is feasible using vascularised, autologous local and also distal tissue transfer in a close interdisciplinary cooperation. PMID:22878359

  12. Evaluation of intraoperative anticoagulants in microvascular free-flap surgery.

    PubMed Central

    Pugh, C. M.; Dennis, R. H.; Massac, E. A.

    1996-01-01

    This retrospective study evaluated anticoagulants used during surgery to determine efficacy and associated complications. The patient population was comprised of 15 patients who underwent microvascular free-flap surgery for wound coverage of the lower one third of the leg. Results indicated that the use of heparin in conjunction with other anticoagulants was associated with the development of more hematomas compared with the use of aspirin and dextran, both separately and together. PMID:8918071

  13. Numerical Simulation of a Flap-Edge Flowfield

    NASA Technical Reports Server (NTRS)

    Streett, C. L.

    1998-01-01

    In this paper we develop an approximate computational framework for simulation of the fluctuating flowfield associated with the complex vortex system seen at the side edge of a flap in a multielement high-lift airfoil system. The eventual goal of these simulations is to provide an estimate of the spectral content of these fluctuations, in order that the spectrum of the noise generated by such flowfields may be estimated. Results from simulations utilizing this computational framework are shown.

  14. Unsteady Adjoint Approach for Design Optimization of Flapping Airfoils

    NASA Technical Reports Server (NTRS)

    Lee, Byung Joon; Liou, Meng-Sing

    2012-01-01

    This paper describes the work for optimizing the propulsive efficiency of flapping airfoils, i.e., improving the thrust under constraining aerodynamic work during the flapping flights by changing their shape and trajectory of motion with the unsteady discrete adjoint approach. For unsteady problems, it is essential to properly resolving time scales of motion under consideration and it must be compatible with the objective sought after. We include both the instantaneous and time-averaged (periodic) formulations in this study. For the design optimization with shape parameters or motion parameters, the time-averaged objective function is found to be more useful, while the instantaneous one is more suitable for flow control. The instantaneous objective function is operationally straightforward. On the other hand, the time-averaged objective function requires additional steps in the adjoint approach; the unsteady discrete adjoint equations for a periodic flow must be reformulated and the corresponding system of equations solved iteratively. We compare the design results from shape and trajectory optimizations and investigate the physical relevance of design variables to the flapping motion at on- and off-design conditions.

  15. Wake Vortex Control using Segmented Rapidly Actuated Gurney Flaps

    NASA Astrophysics Data System (ADS)

    Matalanis, Claude; Eaton, John

    2004-11-01

    Gurney flaps are small flaps oriented perpendicular to the freestream at the trailing edge of a wing, which can increase the lift considerably with little drag penalty. Meso-scale trailing edge effectors (MiTEs) are segmented, rapidly actuated, independent Gurney flaps that have an analogous effect local to their spanwise position. MiTEs show great potential in helping to alleviate the wake vortex hazard. By periodically varying the loading distribution across the span of a wing, it may be possible to excite natural instabilities that accelerate vortex destruction. The problem is to introduce large enough disturbances while holding the total lift of the wing nearly constant. The purpose of this work is to assess how different MiTE actuation patterns can alter the strength and position of the trailing vortex. Our experimental apparatus consists of an untapered NACA 0012 wing with a 30 cm chord length and an aspect ratio of 2 mounted in a wind tunnel. Reynolds numbers based on the chord are of order 105. The wing is equipped with an array of 14 MiTEs. PIV is used to measure tangential velocities of the trailing vortex roughly five chord lengths behind the wing. Data from static MiTE configurations show that the vortex core can be displaced by at least 0.01 chord lengths.

  16. Angio computed tomography preoperative evaluation for anterolateral thigh flap harvesting.

    PubMed

    Ribuffo, Diego; Atzeni, Matteo; Saba, Luca; Milia, Arianna; Guerra, Maristella; Mallarini, Giorgio

    2009-04-01

    The vascular anatomy of the anterolateral thigh flap (ALTF) has many possible variations, and none of the currently used mapping techniques (eg, Echo Color Doppler) gives a thorough knowledge of all details. Among the last generation of angiographic diagnostic techniques, multi detector computed tomography, popularly known as Angio CT, has emerged as an outstanding noninvasive operator independent option, and has been described for deep inferior epigastric perforator and pedicled transverse rectus abdominis muscle planning. This study was conducted to evaluate its usefulness prior to ALTF harvesting.Nine consecutive patients were considered for oral or lower extremity reconstruction with the ALTF. After written informed consent was obtained from all patients, a preoperative Angio-CT study was performed for surgical planning. Accurate identification of septocutaneous or musculocutaneous perforator vessels was achieved and their location, course, and anatomic variations were reported and influenced surgery. Angio CT allows a complete vascular study of the donor area of the ALTF and evaluation of the best perforator vessels before surgery allows surgeons to get an ideal planning of the flap. This imaging method is currently proposed to every patient undergoing ALT flap reconstruction. PMID:19325338

  17. Flapping locomotion of a flexible wing with heaving motion

    NASA Astrophysics Data System (ADS)

    Im, Sunghyuk; Sung, Hyung Jin

    2015-11-01

    The flapping locomotion of a freely heaving flexible wing was experimentally explored in a merry-go-round equipment. Two rectangular wings were attached at the both ends of a horizontal support bar submerged in a dodecagonal water tank. The center of the support bar was connected to the vertically flapping axis which is freely rotating. This experimental apparatus generated a pure heaving motion in the vertical direction to the flapping wings in the frequency range of 0 to 5 Hz. The propulsion due to the heaving wing was expressed by a horizontally rotating speed of the support bar. The heaving motion and the rotating speed were retained with a laser displacement sensor and a rotary encoder. The rotating speed according to the heaving frequency was measured with different experimental parameters. Compared to a rigid wing, the flexible wing in the heaving motion showed a better propulsive performance in some conditions. The effects of the flexibility, the aspect ratio, and the thickness of the heaving wing on the propulsive performance were examined. This work was supported by the Creative Research Initiatives (No. 2015-001828) program of the National Research Foundation of Korea (MSIP).

  18. Flapping-wing mechanical butterfly on a wheel

    NASA Astrophysics Data System (ADS)

    Godoy-Diana, Ramiro; Thiria, Benjamin; Pradal, Daniel

    2009-11-01

    We examine the propulsive performance of a flapping-wing device turning on a ``merry-go-round'' type base. The two-wing flapper is attached to a mast that is ball-bearing mounted to a central shaft in such a way that the thrust force produced by the wings makes the flapper turn around this shaft. The oscillating lift force produced by the flapping wings is aligned with the mast to avoid vibration of the system. A turning contact allows to power the motor that drives the wings. We measure power consumption and cruising speed as a function of flapping frequency and amplitude as well as wing flexibility. The design of the wings permits to change independently their flexibility in the span-wise and chord-wise directions and PIV measurements in various planes let us examine the vorticity field around the device. A complete study of the effect of wing flexibility on the propulsive performance of the system will be presented at the conference.

  19. Numerical and experimental investigations on unsteady aerodynamics of flapping wings

    NASA Astrophysics Data System (ADS)

    Yu, Meilin

    The development of a dynamic unstructured grid high-order accurate spectral difference (SD) method for the three dimensional compressible Navier-Stokes (N-S) equations and its applications in flapping-wing aerodynamics are carried out in this work. Grid deformation is achieved via an algebraic blending strategy to save computational cost. The Geometric Conservation Law (GCL) is imposed to ensure that grid deformation will not contaminate the flow physics. A low Mach number preconditioning procedure is conducted in the developed solver to handle the bio-inspired flow. The capability of the low Mach number preconditioned SD solver is demonstrated by a series of two dimensional (2D) and three dimensional (3D) simulations of the unsteady vortex dominated flow. Several topics in the flapping wing aerodynamics are numerically and experimentally investigated in this work. These topics cover some of the cutting-edge issues in flapping wing aerodynamics, including the wake structure analysis, airfoil thickness and kinematics effects on the aerodynamic performances, vortex structure analysis around 3D flapping wings and the kinematics optimization. Wake structures behind a sinusoidally pitching NACA0012 airfoil are studied with both experimental and numerical approaches. The experiments are carried out with Particle Image Velocimetry (PIV) and two types of wake transition processes, namely the transition from a drag-indicative wake to a thrust-indicative wake and that from the symmetric wake to the asymmetric wake are distinguished. The numerical results from the developed SD solver agree well with the experimental results. It is numerically found that the deflective direction of the asymmetric wake is determined by the initial conditions, e.g. initial phase angle. As most insects use thin wings (i. e., wing thickness is only a few percent of the chord length) in flapping flight, the effects of airfoil thickness on thrust generation are numerically investigated by simulating

  20. [Pedicled supraclavicular osteocutan island flap for tracheostoma closure].

    PubMed

    Agócs, László; Lévay, Bernadett; Boér, András; Elek, Jenő

    2012-12-01

    Authors present a case of a 52-year-old female patient, who underwent an emergency tracheostomy due to life threatening dyspnoea caused by an external compression of a large goiter. Total thyreoidectomy needed to be carried out later, too. Since the atypical tracheostomy did not close spontaneously a reconstruction was planned. A part of the anterior wall of the trachea needed to be replaced, which was done by an osteocutaneous flap on raised on the supraclavicular artery. An island on the artery was harvested with a thin bone chip taken from the coracoid process of the clavicle, which was rotated into the defect then. The bone chip was sutured to the trachea wall and the donor site was closed primarily. Having reviewed the literature the authors propose the application of this flap in a wide range of cases. The advantages of this flap are the satisfactory functional and cosmetic results, as well as the fact that the donor site does not need skin grafting.

  1. Hydrodynamics of a biologically inspired tandem flapping foil configuration

    NASA Astrophysics Data System (ADS)

    Akhtar, Imran; Mittal, Rajat; Lauder, George V.; Drucker, Elliot

    2007-05-01

    Numerical simulations have been used to analyze the effect that vortices, shed from one flapping foil, have on the thrust of another flapping foil placed directly downstream. The simulations attempt to model the dorsal-tail fin interaction observed in a swimming bluegill sunfish. The simulations have been carried out using a Cartesian grid method that allows us to simulate flows with complex moving boundaries on stationary Cartesian grids. The simulations indicate that vortex shedding from the upstream (dorsal) fin is indeed capable of increasing the thrust of the downstream (tail) fin significantly. Vortex structures shed by the upstream dorsal fin increase the effective angle-of-attack of the flow seen by the tail fin and initiate the formation of a strong leading edge stall vortex on the downstream fin. This stall vortex convects down the surface of the tail and the low pressure associated with this vortex increases the thrust on the downstream tail fin. However, this thrust augmentation is found to be quite sensitive to the phase relationship between the two flapping fins. The numerical simulations allows us to examine in detail, the underlying physical mechanism for this thrust augmentation.

  2. Conceptual design of flapping-wing micro air vehicles.

    PubMed

    Whitney, J P; Wood, R J

    2012-09-01

    Traditional micro air vehicles (MAVs) are miniature versions of full-scale aircraft from which their design principles closely follow. The first step in aircraft design is the development of a conceptual design, where basic specifications and vehicle size are established. Conceptual design methods do not rely on specific knowledge of the propulsion system, vehicle layout and subsystems; these details are addressed later in the design process. Non-traditional MAV designs based on birds or insects are less common and without well-established conceptual design methods. This paper presents a conceptual design process for hovering flapping-wing vehicles. An energy-based accounting of propulsion and aerodynamics is combined with a one degree-of-freedom dynamic flapping model. Important results include simple analytical expressions for flight endurance and range, predictions for maximum feasible wing size and body mass, and critical design space restrictions resulting from finite wing inertia. A new figure-of-merit for wing structural-inertial efficiency is proposed and used to quantify the performance of real and artificial insect wings. The impact of these results on future flapping-wing MAV designs is discussed in detail. PMID:22498507

  3. Endoscopic ICG perfusion imaging for flap transplants: technical development

    NASA Astrophysics Data System (ADS)

    Stepp, Herbert; Schachenmayr, Hilmar; Ehrhardt, André; Göbel, Werner; Zhorzel, Sven; Betz, Christian Stephan

    2010-02-01

    Objective: Following tumour surgery in the head and neck region, skin flap transplants are usually required to cover the resection area. The purpose of the development was to provide a simple and reliable means to assess whether the transplanted flap is sufficiently perfused. Methods: Fluorescence of intravenously injected Indocyanine green (ICG) was detected with a slightly modified 3-chip CCD camera. Appropriately coated optical filters allow for excitation of ICG with NIR light and detection of NIR ICGfluorescence with the blue channel of the camera. In addition, low intensities of white light can be transmitted to allow for simultaneous display of a remission image in the green and red channels of the camera. Further processing was performed with a LabVIEW program. Results: A satisfactory white light image (red, green and blue display (RGB)) could be calculated from the remission images recorded with the green and red channels of the camera via a look-up table. The look-up table was programmed to provide an optimized blue intensity value for each combination of red and green values. This was generated using a reference image. Implementation of image tracking and intensity measurements in regions of interest (ROIs) in the images is useful to reliably monitor perfusion kinetics of flap and adjacent normal tissue.

  4. Management of Vortices Trailing Flapped Wings via Separation Control

    NASA Technical Reports Server (NTRS)

    Greenblatt, David

    2005-01-01

    A pilot study was conducted on a flapped semi-span model to investigate the concept and viability of near-wake vortex management via separation control. Passive control was achieved by means of a simple fairing and active control was achieved via zero mass-flux blowing slots. Vortex sheet strength, estimated by integrating surface pressure ports, was used to predict vortex characteristics by means of inviscid rollup relations. Furthermore, vortices trailing the flaps were mapped using a seven-hole probe. Separation control was found to have a marked effect on vortex location, strength, tangential velocity, axial velocity and size over a wide range of angles of attack and control conditions. In general, the vortex trends were well predicted by the inviscid rollup relations. Manipulation of the separated flow near the flap edges exerted significant control over both outboard and inboard edge vortices while producing negligible lift excursions. Dynamic separation and attachment control was found to be an effective means for dynamically perturbing the vortex from arbitrarily long wavelengths down to wavelengths less than a typical wingspan. In summary, separation control has the potential for application to time-independent or time-dependent wake alleviation schemes, where the latter can be deployed to minimize adverse effects on ride-quality and dynamic structural loading.

  5. A pigeon-inspired design for a biomimetic flapping wing

    NASA Astrophysics Data System (ADS)

    Mahardika, Nanang; Nguyen, Quoc Viet; Park, Hoon Cheol

    2010-04-01

    As an effort to explore the potential implementation of wing feather separation and lead-lagging motion to a flapping wing, a biomimetic flapper with separable outer wings has been designed and demonstrated. The artificial wing feather separation is implemented to the biomimetic wing by dividing the wing into inner and outer wings. The features of flapping, lead-lagging and feather separation of the flapper are captured by a high-speed camera for evaluation. The performance of the biomimetic flapper with separable outer wings is compared with that of a flapper with inseparable outer wings in terms of lift and thrust production. For low flapping frequency ranging from 2.47 Hz to 3.90 Hz, the biomimetic flapper shows higher thrust and lift generation capability, which is demonstrated from a series of experiments. The experiments show that the outer parts of the separable wing are able to deform largely resulting smaller amount of drag production during upstroke, while still producing relatively larger lift and thrust during downstroke.

  6. New dimensions for the vital storage of microsurgical free flaps: an experimental approach.

    PubMed

    Mayer, B; von Baeyer, H; Kaiser, U

    1993-10-01

    A revolutionary circulatory system has been developed to nourish big, free osteomusculocutaneous flaps extracorporally. Thus we will be able to transplant the free flaps to defect areas that have no sufficient vascular situation. In respect to the cold storage of microsurgical free flaps, to date maximal periods of ischaemic tolerance have been considerably exceeded; the maximal period is currently 168 hours. The vitality of the flap is monitored through parameters setting forth the consumption of oxygen together with histology and electron microscopy. The oxygenation of the nutritive medium is achieved through an aqueous phase gas exchange. PMID:8233505

  7. The Transverse Musculocutaneous Gracilis Free Flap: Virtual Animation-Assisted Dissection and Application in Breast Reconstruction.

    PubMed

    Gabert, Pierre-Elliott; Bodin, Frederic; Aljudaibi, Nawaf; Duquennoy-Martinot, Veronique; Guerreschi, Pierre

    2016-05-01

    The transverse musculocutaneous gracilis free flap is a valuable choice for autologous tissue, unilateral or bilateral breast reconstruction. This procedure is an excellent and customized option for immediate or delayed breast reconstruction in patients with small to moderate size breasts. Few descriptions of flap dissection and breast mound shaping are available. In this first educational video, the authors report the original dissection of the transverse musculocutaneous gracilis free flap used for breast reconstruction. Virtual animations insist on surgical key points and relevant details of the harvesting of the flap.

  8. Active Flow Control of Lifting Surface With Flap-Current Activities and Future Directions

    NASA Technical Reports Server (NTRS)

    Ahmadi, G.; Marzocca, P.; Jha, R.; Alstorm, B.; Obied, S.; Kabir, P.; Shahrabi, A.

    2010-01-01

    The main objective is to develop effective control strategies for separation control of an airfoil with a single hinge flap. The specific objectives are: Develop an active control architecture for flow control around an airfoil with flap. Design, fabricate, a wind tunnel test of a high lift wing (with flap) with integrated actuators and sensors. Design, development and fabrication of synthetic jet actuators. Develop appropriate control strategy for application to the airfoil. Wind tunnel testing of the high lift wing at various angles of attack and flap positions with closed loop control.

  9. Reinnervated medial gastrocnemius free flap for closure of a recurrent ischial pressure sore: case report.

    PubMed

    Jones, Jonathan W

    2002-07-01

    A 42-year-old T7 level paraplegic man had undergone multiple local flap transfers for closure of a recurrent left ischial pressure sore. When wound breakdown again occurred and regional flap transfers were no longer a possibility, a medial gastrocnemius free flap was transferred to the ischial region. Reinnervation of this flap was accomplished by interposing a sural nerve graft between a proximal intercostal nerve and the tibial motor nerve branch of the gastrocnemius muscle. Following the return of protective sensation, the patient has developed no new ischial pressure ulcerations.

  10. Reverse Medial Hemisoleus Flaps for Coverage of Distal Third Leg Wounds: A Technical Trick.

    PubMed

    Houdek, Matthew T; Wagner, Eric R; Wyles, Cody C; Sems, Stephen A; Moran, Steven L

    2016-04-01

    Traditionally, free tissue transfer has been used to cover wounds of the distal third of the leg. Advances in flap anatomy, elevation, and surgical techniques have allowed the use of pedicled flaps to avoid the use of free tissue transfer in certain situations. The authors describe a technique for using a reversed medial hemisoleus flap to provide soft tissue coverage for wounds of the medial distal leg. In the senior authors experience, the use of this flap has achieved wound coverage in 100% of patients with smaller wounds (≤50 cm) of the medial leg.

  11. Multipaddled Anterolateral Thigh Chimeric Flap for Reconstruction of Complex Defects in Head and Neck

    PubMed Central

    Li, Ning; Liu, Wen; Su, Tong; Chen, Xinqun; Zheng, Lian; Jian, Xinchun

    2014-01-01

    The anterolateral thigh flap has been the workhouse flap for coverage of soft-tissue defects in head and neck for decades. However, the reconstruction of multiple and complex soft-tissue defects in head and neck with multipaddled anterolateral thigh chimeric flaps is still a challenge for reconstructive surgeries. Here, a clinical series of 12 cases is reported in which multipaddled anterolateral thigh chimeric flaps were used for complex soft-tissue defects with several separately anatomic locations in head and neck. Of the 12 cases, 7 patients presented with trismus were diagnosed as advanced buccal cancer with oral submucous fibrosis, 2 tongue cancer cases were found accompanied with multiple oral mucosa lesions or buccal cancer, and 3 were hypopharyngeal cancer with anterior neck skin invaded. All soft-tissue defects were reconstructed by multipaddled anterolateral thigh chimeric flaps, including 9 tripaddled anterolateral thigh flaps and 3 bipaddled flaps. The mean length of skin paddle was 19.2 (range: 14–23) cm and the mean width was 4.9 (range: 2.5–7) cm. All flaps survived and all donor sites were closed primarily. After a mean follow-up time of 9.1 months, there were no problems with the donor or recipient sites. This study supports that the multipaddled anterolateral thigh chimeric flap is a reliable and good alternative for complex and multiple soft-tissue defects of the head and neck. PMID:25180680

  12. Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps

    NASA Astrophysics Data System (ADS)

    Huang, Chong; Radabaugh, Jeffrey P.; Aouad, Rony K.; Lin, Yu; Gal, Thomas J.; Patel, Amit B.; Valentino, Joseph; Shang, Yu; Yu, Guoqiang

    2015-07-01

    Knowledge of tissue blood flow (BF) changes after free tissue transfer may enable surgeons to predict the failure of flap thrombosis at an early stage. This study used our recently developed noncontact diffuse correlation spectroscopy to monitor dynamic BF changes in free flaps without getting in contact with the targeted tissue. Eight free flaps were elevated in patients with head and neck cancer; one of the flaps failed. Multiple BF measurements probing the transferred tissue were performed during and post the surgical operation. Postoperative BF values were normalized to the intraoperative baselines (assigning "1") for the calculation of relative BF change (rBF). The rBF changes over the seven successful flaps were 1.89±0.15, 2.26±0.13, and 2.43±0.13 (mean±standard error), respectively, on postoperative days 2, 4, and 7. These postoperative values were significantly higher than the intraoperative baseline values (p<0.001), indicating a gradual recovery of flap vascularity after the tissue transfer. By contrast, rBF changes observed from the unsuccessful flaps were 1.14 and 1.34, respectively, on postoperative days 2 and 4, indicating less flow recovery. Measurement of BF recovery after flap anastomosis holds the potential to act early to salvage ischemic flaps.

  13. Experimental investigation and modeling of time resolved thrust of a flapping wing aircraft

    NASA Astrophysics Data System (ADS)

    Apker, Thomas B.

    This work presents a novel method of measuring the unsteady thrust of a hovering flapping wing vehicle and the development of phenomenological models to simulate it. The measurements were taken using a balance beam with the flapping wings mounted at one end and a counterweight plus an accelerometer mounted at the other. The trust axis of the flapping wings was mounted vertically, and the counterweight was adjusted to balance the weight and average thrust of the flapping wings. An accelerometer mounted above the counterweight measured the unsteady thrust. This method decoupled the force sensing element from the mass of the flapping wings, as opposed to standard force sensors that use a linear spring. This study showed that the spectral content of the flapping wings extended to 15 times the flapping frequency, well above the resonant frequency of the mass-spring-damper system formed by a load cell and flapping mechanism. High speed video of the wings was used to determine the motion of the flexible structure. This motion was used to develop phenomenological linear models of flapping wing thrust generation. The results show that this approach to linear modeling produces a system of equations that can be used for flight dynamics simulation and controller design.

  14. The use of the temporoparietal fascia flap in various clinical scenarios: A review of 71 cases

    PubMed Central

    Mokal, Nitin J; Ghalme, Amol N; Kothari, Deepak S; Desai, Mahinoor

    2013-01-01

    Objective: This report details our experience with the use of the temporoparietal fascia flap in different scenarios of reconstruction and to discuss our technique of harvest, clinical applications, and review of literature of this versatile flap. Materials and Methods: A retrospective study of 82 cases of temporoparietal fascia flap in 71 patients, operated over a period of 10 years was conducted. Patients were grouped based on various clinical indications. The follow up period ranged from a minimum of 1 to a maximum of 10 years (Mean-four and a half years). All patients were analyzed for functional and aesthetic outcome using preoperative and postoperative photographs. Results: No significant complications were seen in our series. Only 2 out of 82 flaps had partial necrosis of flap (2.44%). Two patients who were operated for release of submucous fibrosis developed recurrence due to continued use of tobacco. The final outcome in one patient of ear reconstruction was unsatisfactory due to flap failure. The remaining patients had satisfactory functional and aesthetic outcomes (95.77%). None had other complications like temporal branch of facial nerve injury or alopecia along the scar line. Conclusion: The TPFF is one of the most reliable and versatile flap in the head and neck region. It can also be reliably used as free fascial flap. When its advantages are combined with the surgeon's resourcefulness, various defects can be successfully reconstructed using the temporoparietal facia flap with satisfactory aesthetic and functional outcome. PMID:24459337

  15. Influence of a pedicle flap design on acute postoperative sequelae after lower third molar removal.

    PubMed

    Goldsmith, Sam M; De Silva, Rohana Kumara; Tong, Darryl C; Love, Robert M

    2012-03-01

    Pain, swelling, trismus, and alveolar osteitis often occur after removal of impacted third molar teeth. To minimize these complications a number of mucoperiosteal flap designs have been advocated, but, to date, a pedicle flap design has not been evaluated. In a randomized prospective split mouth study, 52 participants had bilateral symmetrically impacted mandibular third molars removed over two sessions. A buccal envelope or pedicle flap was randomly assigned to the left or right third molar site. Pre-and postoperative pain and swelling were recorded using a standardized visual analogue scale, trismus was measured as the maximum inter-incisal opening distance in millimetres and dry socket was assessed clinically. Greater continuous pain, pain on maximum opening, and oro-facial swelling were recorded with the pedicle flap design. Continuous pain resolved significantly faster with this flap design (p<0.05). Trismus was similar for both flap designs (p>0.05). Five cases of alveolar osteitis occurred with the envelope flap whilst no cases developed with the pedicle flap, but the incidence was too small for statistical analysis. The pedicle flap improved some aspects of postoperative pain experience and reduced the incidence of alveolar osteitis, but further investigation with a larger sample size is required to evaluate its significance.

  16. Reconstruction of Heel With Propeller Flap in Postfasciotomy and Popliteal Artery Revascularization State.

    PubMed

    Kang, Jin Seok; Choi, Hwan Jun; Tak, Min Sung

    2016-06-01

    Free flaps are still the gold standard for large defects of the lower limb, but propeller perforator flaps have become a simpler and faster alternative to free flaps because of some advantages such as reliable vascular pedicle, wide mobilization and rotation, great freedom in design, low donor site morbidity, and easy harvest with no requirement for anastomosis. But when the vessels show insufficient findings in preoperative evaluation using a Doppler probe or the vessel is injured, the surgeon should avoid performing free flap surgery to prevent flap failure and should select a propeller perforator flap as an alternative method on the condition that more than one perforator is intact. In this study, we report reconstruction of soft tissue defects of the heel with a pedicled propeller flap in postfasciotomy and popliteal artery revascularization state by making an incision on the central portion above the Achilles tendon, which can be covered by the posterior tibial artery perforator or the peroneal artery perforator based flaps. In conclusion, we showed that although the popliteal artery was injured, the soft tissue defect can be reconstructed using a perforator propeller flap if intact distal flow in the anastomosis site was confirmed.

  17. Dorsal Intercostal Artery Perforator Propeller Flaps: A Reliable Option in Reconstruction of Large Meningomyelocele Defects.

    PubMed

    Basterzi, Yavuz; Tenekeci, Goktekin

    2016-04-01

    Several options have been reported for the reconstruction of myelomeningocele defects. In this article, we present our experience on soft tissue reconstruction of myelomeningocele defects by using island propeller dorsal intercostal artery perforator (DIAP) flaps. Between January 2008 and February 2014, all newborns with large myelomeningocele defects (13 newborns) were reconstructed with island propeller DIAP flaps. All flaps survived completely. In 8 patients out of 13, venous insufficiency was observed which then resolved spontaneously. Flap donor sites were closed primarily. Myelomeningocele defects with a diameter larger than 5 cm require reconstruction with flaps. To mobilize a well-vascularized tissue over the defect without tension in which the suture lines will not overlap over the midline where the dura is repaired and over the meninges is one of the goals of reconstruction for such defects. Perforator propeller flaps enable us to reach those goals. Use of perforator flaps provides 2 important advantages, namely, more predictability and also more freedom in mobilizing flaps toward the defect. This study proves the reliability of DIAP propeller flaps in the reconstruction of myelomeningocele defects.

  18. Pressure Distribution Over a Rectangular Airfoil with a Partial-Span Split Flap

    NASA Technical Reports Server (NTRS)

    Wenzinger, Carl J; Harris, Thomas A

    1937-01-01

    This report presents the results of pressure-distribution tests of a Clark y wing model with a partial-span split flap made to determine the distribution of air loads over both the wing and the flap. The model was used in conjunction with a reflection plane in the NACA 7 by 10 foot wind tunnel. The 20-percent-chord split flap extended over the inboard 60 percent of the semispan. The tests were made at various flap deflections up to 45 degrees and covered a range of angles of attack from zero lift to approximately maximum lift for each deflection.

  19. Development of Bird-like Micro Aerial Vehicle with Flapping and Feathering Wing Motions

    NASA Astrophysics Data System (ADS)

    Maglasang, Jonathan; Goto, Norihiro; Isogai, Koji

    To investigate the feasibility of a highly efficient flapping system capable of avian maneuvers, such as rapid takeoff, hover and gliding, a full scale bird-like (ornithopter) flapping-wing micro aerial vehicle (MAV) shaped and patterned after a typical pigeon (Columba livia) has been designed and constructed. Both numerical and experimental methods have been used in the development of this vehicle. This flapping-wing micro aerial vehicle utilizes both the flapping and feathering motions of an avian wing by employing a novel flapping-feathering mechanism, which has been synthesized and constructed so as to best describe the properly coordinated flapping and feathering wing motions at phase angle difference of 90° in a horizontal steady level flight condition. This design allows high flapping and feathering amplitudes and is configurable for asymmetric wing motions which are desirable in high-speed flapping flight and maneuvering. The preliminary results indicate its viability as a practical and an efficient flapping-wing micro aerial vehicle.

  20. Functional assessment: Free thin anterolateral thigh flap versus free radial forearm reconstruction for hemiglossectomy defects

    PubMed Central

    Lu, Mingxing; Hu, Qingang; Tang, Enyi; Wang, Yujia

    2015-01-01

    Background To compare free thin anterolateral thigh (ALT) flap with free radial forearm (FRF) flap in the reconstruction of hemiglossectomy defects, and to introduce our methods and experience in the tongue reconstruction with free thin ALT flap. Material and Methods The clinicopathologic data of 46 tongue carcinoma cases hospitalized from December 2009 to April 2014 were obtained from Nangjing Stomatological Hospital, Medical School of Nanjing University. All the subjects were evaluated for the articulation and the swallowing function 3 months after the surgery. Results Among these 46 patients, 12 patients underwent tongue reconstruction after hemiglossectomy with ALT flap; 34 patients underwent tongue reconstruction with FRF flap. The differences in the incidence of vascular crisis, the speech and the swallowing function between two groups were not significant (P>0.05). Conclusions Thin ALT flap could be one of the ideal flaps for hemiglossectomy defect reconstruction with its versatility in design, long pedicle with a suitable vessel diameter, and the neglectable donor site morbidity. Key words:Free thin anterolateral thigh flap, free radial forearm flap, hemiglossectomy, reconstruction, morbidity. PMID:26449437