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Sample records for bulbocavernosus myocutaneous flaps

  1. The platysma myocutaneous flap.

    PubMed

    Baur, Dale A; Williams, Jonathan; Alakaily, Xena

    2014-08-01

    Reconstructing defects of the oral mucosa or skin of the lower one-third of the face can be accomplished by a variety of techniques. This article presents two versions of the platysma myocutaneous flap, which is a reliable, axial pattern, pedicled flap capable of providing excellent one-stage reconstruction of such defects. As discussed herein, the superiorly based and posteriorly based versions of the flap have wide application in the oral and facial region. Also provided is a review of other uses of this flap in head and neck surgery. PMID:24958382

  2. Rectus abdominis myocutaneous flap for primary vaginal reconstruction.

    PubMed

    Carlson, J W; Soisson, A P; Fowler, J M; Carter, J R; Twiggs, L B; Carson, L F

    1993-12-01

    Reconstructive procedures are being performed with increasing frequency in conjunction with pelvic exenterations and other radical gynecologic surgeries. The most common reconstructive procedures include continent urinary diversion, rectosigmoid anastomosis, and vaginal reconstruction. Historically, the gracilis myocutaneous flap has been the procedure of choice for vaginal reconstruction. However, the gracilis myocutaneous flap has a history of partial to severe necrosis, a propensity to prolapse, and leaves ipsilateral donor scars on the thigh. In contrast, neovaginal reconstruction using a relatively new procedure, the distally based rectus abdominis myocutaneous flaps, has the advantage of using a large, single flap that can be incorporated into the primary incision. This flap is mobilized on a long vascular pedicle, the rectus muscle. In relation to the underlying rectus muscle, the orientation of the cutaneous portion of this flap may be customized to accommodate the pelvic defect or the surgeon's preference. Depending on their primary orientation, they are referred to as either a vertical or transverse rectus abdominis myocutaneous flap. The versatility and reliability of the rectus flap is demonstrated here through the presentation of a small pilot series of seven patients. The technique was used for vaginal reconstruction, primarily in conjunction with pelvic exenteration. The flaps were mobilized from the supraumbilical area and had a flap viability of 100% for the 2 years that they have been followed. There were no postoperative incisional or flap infections. There was one infraumbilical fascial dehiscence. The advantages of primary pelvic reconstruction along with the description of the operative techniques are presented. PMID:8112640

  3. Gynecologic reconstruction with a rectus abdominis myocutaneous flap: an update.

    PubMed

    Carlson, J W; Carter, J R; Saltzman, A K; Carson, L F; Fowler, J M; Twiggs, L B

    1996-06-01

    This series reports the outcomes and significant complications associated with the rectus myocutaneous flap when used for pelvic or inguinal reconstruction in patients with gynecologic cancers. Perioperative variables were retrospectively reviewed to identify social and medical risk factors as well as intraoperative and postoperative complications that predisposed to rectus flap failure. Fifteen patients with gynecologic malignancies underwent reconstructive procedures using a vertically oriented rectus abdominis myocutaneous flap for either vaginal (n = 14) or inguinal (n = 1) reconstruction. The patients' primary cancers were cervical (n = 11), rectal (n = 1), ovarian (n = 1), vulvar (n = 1), and vaginal (n = 1). The median age was 50 years. The median follow-up was 17 months. All flaps were mobilized in conjunction with a radical salvage operation. There were no cases of vaginal prolapse and no abdominal wound infections. However, 4 patients (27%) had major postoperative morbidity in this small series. There was one wound dehiscence and three episodes of necrosis of the subcutaneous and cutaneous portions of the flap. All 4 of these patients required additional operative intervention or debridement. Eleven patients had complete healing of the flap. The rectus abdominis myocutaneous flap is a valuable option for gynecologic reconstructive procedures. Perioperative strategies for improving flap viability include the identification of risk factors that may compromise flap perfusions such as prior abdominal incisions, peripheral vascular disease, and obesity. Meticulous surgical technique is required to preserve the vascular pedicle. These strategies may be useful in preoperative counseling, the perioperative evaluation, and the intraoperative management. PMID:8641616

  4. 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.

  5. Treatment of Sternal Wound Infection Using a Free Myocutaneous Flap.

    PubMed

    Chiang, I-han; Chen, Shyi-Gen; Wang, Chih-Hsin

    2015-11-01

    Deep sternal wound infections are potentially life-threatening complications after cardiac operations because they can spread into the mediastinum and cause postoperative morbidity and mortality. We present a 65-year-old man with a history of coronary artery bypass grafting. A large sternal defect was left after debridement. After brief vacuum-assisted closure (VAC), a free myocutaneous flap of the anterolateral thigh (ALT) was used to fill the dead space. At the 9-month follow-up, the wound had healed completely without tissue loss or complications, and the patient returned to normal life. This was a successful treatment of a deep sternal wound with free flap coverage. PMID:26522542

  6. 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

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

    PubMed

    Edmunds, Marie-Claire; Czopek, Alicja; Wigmore, Stephen J; Kluth, David C

    2014-01-01

    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

  8. A bilobed thoracoabdominal myocutaneous flap for large thoracic defects.

    PubMed

    Charanek, Ali M

    2014-04-01

    The author presents a surgical procedure for chest-wall soft tissue reconstruction due to large losses based on a modified thoracoabdominal myocutaneous flap. Designed in a bilobed shape, it rests on the superior epigastric vessels and may include the cranial one fourth of the rectus abdominis muscle and the premuscular fascia of external oblique muscle and constitutes one of the largest flaps based on a single minor artery. Local recurrent breast tumors and adjuvant therapy associated to obesity, high blood pressure, type II diabetes, and tobacco abuse on previously debilitated patients render the usual reconstructive procedure difficulties. These become indications for this flap, whose safety is improved by maintaining the deep fascia of the external oblique muscle attached to the flap to preserve the network of the arteries close to the fascia and a wide-ranging interarterial choke anastomosis alongside the lateral projection of the flap on the thorax. Thus, a wide range of angles allows us to reach even the opposite site of the thorax over the sterna area with an easy closure of the donor site facilitated by the vertical portion of the abdominal donor site. The flap was used in 55 patients, and no serious complications, including necrosis, notable dehiscence, hematoma, seroma, or abdominal wall weakness, were observed. The overall aspect is acceptable with the visible scars over the upper part of the abdomen. PMID:23503434

  9. The pedicled latissimus dorsi myocutaneous flap in head and neck reconstruction.

    PubMed

    Ong, Hui Shan; Ji, Tong; Zhang, Chen Ping

    2014-08-01

    The pedicled latissimus dorsi myocutaneous flap (PLDMF) is not the first-line reconstructive option for most clinicians; however, when treating salvage patients or those with depleted neck vessels, the PLDMF provides a valuable armamentarium. Unlike the pectoralis major myocutaneous flap or the lower island trapezius flap, the PLDMF has greater versatility in soft tissue design and a longer arc of rotation. These advantages are of great importance in managing advanced reconstructive cases. PMID:24958381

  10. Use of a bilobed gracilis myocutaneous flap in perineal and genital reconstruction.

    PubMed

    Vyas, Raj M; Pomahac, Bohdan

    2010-08-01

    The gracilis myocutaneous flap has limited functional donor site morbidity and effectively contours genitoperineal reconstructions. When harvested using a traditional vertical skin paddle, distal-tip necrosis (secondary to inconsistent perforator anatomy) is a well-documented complication. Orienting the skin paddle transversely provides a reliable alternative with a shorter rotational arc but results in a more conspicuous deformity and smaller skin paddle when primary closure is desired. On the basis of recent anatomic studies, we designed a pedicled gracilis myocutaneous flap with a bilobed cutaneous paddle to maximally incorporate both the transverse and longitudinal dimensions of the flap's nearly circular angiosome. The bilobed design allows harvest of a larger transverse skin flap (with a shorter arc of rotation) while a shorter, more dependable vertical skin flap is inset into the transverse flap donor site (rather than inside the critical wound bed). Herein, we detail our surgical technique and provide 2 illustrative case examples. PMID:20606582

  11. [Mediastinal tracheotomy in cervicofacial oncologic surgery. Contribution of the pectoralis major myocutaneous flap].

    PubMed

    Hamoir, M; Calteux, N; Robillard, T; Remacle, M; De Coninck, A; Van Den Eeckhaut, J

    1985-01-01

    Four cases of anterior mediastinal tracheostomy with myocutaneous Pectoralis Major flap are described. Resection of the manubrium, clavicular heads and the cartilages of the first and second ribs is necessary. The use of myocutaneous Pectoralis Major flap give good functional results. No infection or hemorrhage of mediastinal great vessels occurred. The indications of Anterior mediastinal tracheostomy are discussed. Stomal and peristomal recurrences following laryngectomy for carcinoma represents the indication of choice. Stomal recurrences are difficult to treat and the prognostic is poor. Prevention of the stomal recurrences is discussed. PMID:4014936

  12. Medial and Lateral Canthal Reconstruction with an Orbicularis Oculi Myocutaneous Island Flap

    PubMed Central

    Han, Jihyeon; Kwon, Sung Tack; Kim, Suk Wha

    2015-01-01

    Background The eyelid and canthal areas are common locations for cutaneous tumors. The medial canthus includes, among many other apparatuses, the canthal tendon and lacrimal canaliculi, and its characteristic thin and supple skin is hard to mimic and restore using tissue from other regions. Accordingly, reconstruction of the canthal area can prove challenging for surgeons. Although various methods, such as skin grafts and local flaps from adjacent regions, have been utilized for reconstructive purposes, they present known disadvantages. However, we were able to successfully reconstruct both lateral and medial canthal area defects by using orbicularis oculi myocutaneous island flaps. Methods Our study included seven patients who underwent medial or lateral canthal region reconstruction, using orbicularis oculi myocutaneous island flaps, between 2011 and 2014, following either cutaneous tumor excision or traumatic avulsion injury. Results Five patients had basal cell carcinoma, one had squamous cell carcinoma of the eyelid, and one had sustained a traumatic avulsion injury of the eyelid and canthal area. Entire flap loss was not observed in any patient, but one-a heavy smoker-showed partial flap loss, which healed with secondary intention and yielded acceptable results. Donor site morbidity was not observed, and all patients were satisfied with their surgical outcomes. Conclusions The canthal regions can be successfully reconstructed with orbicularis oculi myocutaneous island flaps. These flaps offer several key advantages, including similarity in texture, color, and thickness to the recipient site and a negligible incidence of donor site morbidity. PMID:25606488

  13. Pharmacologic manipulation of the microcirculation in cutaneous and myocutaneous flaps in pigs

    SciTech Connect

    Pang, C.Y.; Neligan, P.C.; Nakatsuka, T.; Sasaki, G.H.

    1985-04-01

    The vascular effects of isoxsuprine, diazoxide, and isoproterenol were studied in arterial buttock flaps and latissimus dorsi myocutaneous flaps in pigs. Capillary blood flow to the skin and muscles of these flaps was measured by the radioactive microsphere (15-mu diameter) technique 6 hours postoperatively under pentobarbital anesthesia. It was observed that isoproterenol, a beta-adrenergic receptor agonist, was not effective in augmentation of skin blood flow in the arterial buttock flaps. However, isoproterenol significantly increased capillary blood flow to the arterialized portion of latissimus dorsi myocutaneous flaps compared with controls. Isoxsuprine and diazoxide (vascular smooth muscle relaxants) significantly (p less than 0.05) increased total capillary blood flow to the skin of arterial buttock flaps and to the skin and muscles of the latissimus dorsi myocutaneous flaps. However, the increase in capillary blood flow occurred mainly in the arterialized portion of these flaps. The capillary blood flow, which was supplied by the small arteries in the distal portion of the arterial buttock and latissimus dorsi flaps, was not increased by treatment with isoxsuprine or diazoxide. Therefore, there was also no increase in the maximum distance of capillary blood flow from the pedicle to the distal end of the flaps. These observations led the authors to hypothesize that different sizes (diameters) of arteries in the skin and muscle have different reactivity (or sensitivity) to vasodilatory drugs. In the present experiment, the large dominant artery of the arterial buttock and latissimus dorsi flaps responded to isoxsuprine or diazoxide (vascular smooth-muscle relaxants), resulting in an increase in blood supply to the capillaries in the proximal portion of the flaps.

  14. Herpes Zoster in a Free Transverse Rectus Abdominis Myocutaneous Flap After Delayed Breast Reconstruction

    PubMed Central

    Lee, Jeong Hui; Ahn, Hee Chang; Chung, Min Sung

    2015-01-01

    Abstract In concert with advances in surgical reconstruction techniques and improved survival after breast cancer, both the aesthetic and functional outcomes, especially sensory recovery, of breast reconstruction have been addressed. Most studies on sensory recovery in reconstructed breasts have utilized patients’ subjective responses to touch, pain, temperature, and pressure. In contrast, this report describes a case of herpes zoster that developed in a free transverse rectus abdominis myocutaneous flap, which provides objective evidence of spontaneous reinnervation after breast reconstruction. PMID:25974118

  15. Immediate nipple reconstruction with thoracodorsal artery perforator flap in breast reconstruction by latissimus dorsi myocutaneous flap in patients with Poland's syndrome.

    PubMed

    He, Jinguang; Xu, Hua; Wang, Tao; Qiao, Yufei; Zhang, Yi; Dong, Jiasheng

    2016-01-01

    Loss of long-term projection is the major disadvantage of nipple reconstruction using local flaps. We report a technique of immediate perforator flap nipple reconstruction in breast reconstruction by latissimus dorsi (LD) myocutaneous flap in patients with Poland's syndrome. From March 2007 to July 2012, 12 female patients (age range, 15-21 years) underwent breast reconstructions and immediate nipple reconstructions. A thoracodorsal artery perforator (TAP) flap was simultaneously raised on the LD muscle flap and folded by itself to form the nipple. Both the LD flap and TAP flaps survived postoperatively. The nipple projection was measured by a caliper, and the average loss was 29% by the 1-year follow-up. Eleven patients considered the aesthetic appearance of reconstructed breast and nipple to be very good or good. The immediate nipple reconstruction with TAP flap could be safely performed and results in considerable satisfaction in breast reconstruction by LD myocutaneous flap in patients with Poland's syndrome. PMID:25752505

  16. 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

  17. 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. PMID:24401809

  18. Breast reconstruction with a turbocharged transverse rectus abdominis myocutaneous flap on the contralateral perforator.

    PubMed

    Sbalchiero, Juliano Carlos; de Albuquerque Leal, Paulo Roberto; dos Santos, César Cabello

    2014-11-01

    Seventeen patients were submitted to delayed unilateral breast reconstruction using pedicled, muscle-sparing turbocharged transverse rectus abdominis myocutaneous flap based on the contralateral perforator vessels. The lateral portion of the rectus abdominis muscle on the pedicled side was preserved in 12 patients. Zones II and IV were included in the flap in all cases. Mean duration of surgery was 7 hours and 15 minutes. Four complications developed in the abdominal donor site: contralateral abdominal bulging (n=1), minor suture dehiscence (n=2), and epidermolysis at the border of the abdominal flap and umbilical scar (n=1). Three partial losses (10%-30%) occurred in the reconstructed breast (17.64% of cases), whereas 2 cases of fat necrosis were associated with partial losses. One patient developed deep vein thrombosis with pulmonary embolism; however, outcome was favorable. This proved a viable alternative for breast reconstruction, with satisfactory results in most patients and acceptable morbidity and surgical time. PMID:24625511

  19. Treatment of the severely infected frontal sinus with latissimus dorsi myocutaneous free flaps.

    PubMed

    Kim, Youn Hwan; Youn, Seung Ki; Kim, Jeong Tae; Kim, Sang Wha; Yi, Hyeong Joong; Kim, Chang Yeon

    2011-05-01

    In trauma patients with severe intracranial hemorrhaging, diagnosing facial bone fractures can be delayed. In frontal sinus fractures with nasofrontal duct obstruction, obliteration of the nasofrontal duct and the sinus is the current treatment of choice. But with inadequate management, ascending infections happen, and widely spread infections can involve the entire frontal soft tissues, which result in meningitis, encephalitis, and subcutaneous abscess pockets creating skin defects. In the treatment of these infections, radical debridement of all infected tissues including galea, pericranium, and surrounding soft tissues is obligatory; hence, available local vascularized flap options for obliteration of the postdebridement defect are scarce. In these situations, free-tissue transfer can be a treatment option. Although there have been numerous reports of using nonvascularized materials for obliteration of the frontal sinus, the material itself can serve as a nidus for infection, and it is generally accepted that well-vascularized tissues have greater ability to withstand local soft-tissue infection and osteomyelitis. Hence, we report 3 cases where we performed latissimus dorsi myocutaneous flaps for severe frontal sinus infections after frontal cranioplasty for severe hemorrhaging. Large bulks of muscle obliterated the nasofrontal duct and the dead space surrounding the entire frontal sinus. The latissimus dorsi myocutaneous flap is not a permanent solution for frontal sinus reconstruction, which requires a secondary bony reconstruction. However, when we face acute stages of intractable infections of the frontal sinus, it can control the infection and result in saving the patient's life. PMID:21558912

  20. 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

  1. [Perineal soft-tissue reconstruction with vertical rectus abdominis myocutan (VRAM) flap following extended abdomino-perineal resection for cancer].

    PubMed

    Bognár, Gábor; Novák, András; István, Gábor; Lóderer, Zoltán; Ledniczky, György; Ondrejka, Pál

    2012-10-01

    Perineal wound healing problems following extended abdomino-perineal resection of ano-rectal cancer represent a great challenge to the surgeon. Perineal soft-tissue reconstruction with a myocutan flap was thought to reduce surgical wound healing complications. A review of the relevant literature was carried out on perineal soft-tissue reconstruction with rectus abdominis myocutan (VRAM) flap following extended abdomino-perineal rectal resection for cancer. The more commonly used neoadjuvant chemo- and radiotherapy as well as extended surgical radicality resulted in increased perioperative risks, therefore combined procedures between the colorectal and plastic surgical teams are inevitable. This case report illustrates the above trend. PMID:23086826

  2. Muscular, myocutaneous, and fasciocutaneous flaps in complex urethral reconstruction.

    PubMed

    Zinman, Leonard

    2002-05-01

    The ability to achieve a long-term, stable, stricture-free, hairless urethral lumen in patients with complex anterior stricture and compromised genital skin is one of the ongoing challenges of reconstructive urologic surgery. The conservative approach by endoscopic urethrotomy or dilatation with a self-catheterization schedule rarely affects a definitive cure except in the short filmy superficial strictures of the bulbous portion of the urethra. Genital fasciocutaneous island flaps are currently the golden standard for definitive, reliable resolution of anterior urethral strictures in patients who have not undergone a prior surgical procedure that may alter the penile or scrotal circulation, or those with skin loss from trauma, decubiti, radiation, or balanitis xerotica obliterans. PMID:12371235

  3. Reconstruction of large composite oromandibulomaxillary defects with free vertical rectus abdominis myocutaneous flaps.

    PubMed

    Butler, Charles E; Lewin, Jan S

    2004-02-01

    Large composite oromandibulomaxillary defects resulting from oncologic resection can be challenging to reconstruct with a single flap, and functional outcomes remain anecdotal. The purpose of this study was to evaluate the authors' surgical experience and scientifically analyze and describe the functional outcomes associated with the use of the vertical rectus abdominis myocutaneous flap for reconstruction of these defects. The records of seven patients (mean age, 62 years) who underwent composite resection including hemimandibulectomy, partial maxillectomy, partial pharyngectomy, and floor-of-mouth resection followed by immediate free vertical rectus abdominis myocutaneous flap reconstruction at The University of Texas M. D. Anderson Cancer Center (1998 to 2002) were retrospectively reviewed. The tumor type was squamous cell carcinoma in all seven cases; four patients had T4 primary lesions and three had local recurrences. Radiotherapy was used preoperatively in each of the three recurrent cases (mean dose, 70.6 Gy) and postoperatively in three of the four patients with primary tumors (mean dose, 63.0 Gy). The mean length of hospitalization was 8.7 days. There were no major flap complications, fistulas, or donor-site complications. Partial flap necrosis (4 percent of flap area) occurred in one patient and dehiscence of the neck incision occurred in another. Both cases were managed with surgical débridement and closure. A third patient developed a 0.75-cm superficial suture line abscess that healed with dressing changes. The mean postoperative follow-up was 15 months. Six of the seven patients remained tube dependent for their nutrition despite some swallowing improvement; one patient returned to full oral intake. The most common swallowing deficit was impaired laryngeal excursion, which occurred in all six patients evaluated with videofluoroscopic examination and resulted in risk for aspiration in patients and frank aspiration in 83 percent. Speech was

  4. Initial experience with breast reconstruction using the transverse rectus abdominis myocutaneous flap: a study of 45 patients.

    PubMed Central

    Andrews, E.; Bond, J.; Dolan, S.; Kirk, S.

    1999-01-01

    Breast conserving surgery for breast cancer has led to an increased interest in reconstruction following mastectomy. The transverse rectus abdominis myocutaneous flap has been proven to give good results in terms of restoration of body symmetry with near normal contour and consistency. Furthermore, immediate reconstruction has the advantage of a single procedure with less psychological morbidity, and reduction in hospital stay and overall complication rate. The aim of this study was to review our experience with the transverse rectus abdominis myocutaneous flap procedure an initial series of 45 patients. The overall complication rate of 27% is similar to that reported in the literature, with no total flap loss and nine patients with partial flap loss. There was no delay in commencement of adjuvant chemotherapy or radiotherapy and we believe our ability to detect local recurrence has not been compromised. We consider that immediate breast reconstruction is now an integral part of the surgical treatment of breast cancer. PMID:10489808

  5. [Latissimus dorsi myocutaneous flap combined with implant in breast reconstruction: The technique of the dorsal bra].

    PubMed

    Bruant-Rodier, C; Chiriac, S; Baratte, A; Dissaux, C; Bodin, F

    2016-06-01

    The latissimus dorsi myocutaneous flap combined with an implant is an effective breast reconstruction solution especially in irradiated patients. The authors describe the specific technical aspects that allow them to optimize the results of this intervention. In the back, the skin paddle is drawn in the shape of a horizontal spindle so as to conceal the residual scar under the bra. In breast area, a J-shaped contraincision barring the mastectomy scar ensures a harmonious positioning of the skin paddle to the inferolateral part of the breast. After a 180° rotation, the latissimus dorsi muscle envelops the implant like a bra. Its upper edge is attached at the bottom to define the new submammary fold. Under the pectoralis major muscle, its distal end comes to fill the décolleté above the implant. PMID:26117706

  6. 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

  7. 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

  8. Use of the platysma myocutaneous flap for cervical trachea reconstruction: an experimental study in dogs.

    PubMed

    de Mello-Filho, F V; Mamede, R C; Sader, A A; Velludo, M A; Vicente, W V

    1993-10-01

    Cervical trachea reconstruction with a non-stented platysma myocutaneous door flap (NPMCF) was studied in 23 dogs. Window defects involving 5, 10, or 15 rings and the whole anterior tracheal wall were produced in 3 different groups of animals. A segmentary defect involving the resection of 3 tracheal rings but preserving the posterior membranous wall was created in another group. The results were evaluated by clinical follow-up of up to 100 days, by tracheoscopy 1 week after surgery, and by macroscopic and microscopic examination after the animals' natural death or sacrifice. The NPMCF proved to be adequate for the reconstruction of window defects limited to 5 and 10 rings, with success rates of 100% and 75%, respectively. The use of the NPMCF for tracheal reconstruction had the following main advantages: 1. relatively simple, easy, and expeditious surgery; 2. use of a single operative field; 3. availability of large amounts of donor tissue; 4. adequate thickness; 5. reliable irrigation; 6. resistance to environmental exposure as evidenced by absence of infection; and 7. 100% take rate with no granulomas or scar stenosis at the suture lines. However, luminal occlusion due to flap collapse was a 100% fatal complication when the NPMCP was used either for reconstruction of larger window tracheal defects (15 rings-group 3) or segmentary defects (group 4); this was the main limitation of the method, followed by hair growth with accumulation of secretions, which can be easily dealt with. It can be anticipated that this method has a potential for application in well-selected patients. PMID:8412455

  9. Squamous cell carcinoma of the heel with free latissimus dorsi myocutaneous flap reconstruction: case report and technical note.

    PubMed

    Al Maksoud, Ahmed Mahmoud; Barsoum, Adel K; Moneer, Mohammed

    2016-01-01

    Squamous cell carcinoma (SCC) is the second most common skin cancer; however, it is relatively rare on the foot. Wide excision of SCC is the recommended surgical treatment. The extent of the excision may involve resection of muscles and bone in cases of deep lesions. The functional and anatomic properties and lack of sufficient locally available tissues make the reconstruction of post-oncosurgical defects of the foot a challenging process. Heel reconstruction poses the biggest challenge due to the unique weight-bearing requirements. We present a case of a Marjolin's ulcer on the heel in a 62-year-old woman complicating a chronic non-healing wound. The heel defect was reconstructed with a free latissimus dorsi myocutaneous flap with delayed secondary closure. The outcome was successful both functionally and cosmetically. No further procedures were needed. PMID:27161144

  10. Squamous cell carcinoma of the heel with free latissimus dorsi myocutaneous flap reconstruction: case report and technical note

    PubMed Central

    Al Maksoud, Ahmed Mahmoud; Barsoum, Adel K.; Moneer, Mohammed

    2016-01-01

    Squamous cell carcinoma (SCC) is the second most common skin cancer; however, it is relatively rare on the foot. Wide excision of SCC is the recommended surgical treatment. The extent of the excision may involve resection of muscles and bone in cases of deep lesions. The functional and anatomic properties and lack of sufficient locally available tissues make the reconstruction of post-oncosurgical defects of the foot a challenging process. Heel reconstruction poses the biggest challenge due to the unique weight-bearing requirements. We present a case of a Marjolin’s ulcer on the heel in a 62-year-old woman complicating a chronic non-healing wound. The heel defect was reconstructed with a free latissimus dorsi myocutaneous flap with delayed secondary closure. The outcome was successful both functionally and cosmetically. No further procedures were needed. PMID:27161144

  11. Risk factors of recipient site infection in head and neck cancer patients undergoing pectoralis major myocutaneous flap reconstruction.

    PubMed

    Wang, Chao-Hsien; Wong, Yong-Kie; Wang, Ching-Ping; Wang, Chen-Chi; Jiang, Rong-San; Lai, Chih-Sheng; Liu, Shih-An

    2015-11-01

    The aim of this study was to investigate the factors associated with infection at the recipient site of pectoralis major myocutaneous flap (PMMF) of head and neck cancer patients. We retrospectively reviewed head and neck cancer patients who underwent PMMF reconstruction and identified those with recipient site infection. Variables of patients with and without infection were compared and associated factors were investigated by logistic regression model. A total of 478 patients were included in the final analysis and 183 patients (38.3%) developed recipient site infection. Lower margin of skin island, concurrent tracheotomy, diabetes mellitus, mandibular plate reconstruction, prior radiation, and peri-operative blood transfusion were independent factors associated with recipient site infection of PMMF. Skin island of PMMF beyond the eighth intercostal space markedly increased the risk of recipient site infection after major head and neck cancer surgery. Recognition of relevant factors associated with infection may help surgeons to identify those at risk. PMID:25359197

  12. Recurrent cystosarcoma phylloides of breast: extensive full-thickness excision of chest wall with immediate repair using steel mesh and a latissimus dorsi myocutaneous flap.

    PubMed

    Mindikoğlu, A N; Aktan, K

    1983-10-01

    The case of a young woman with a massive recurrent cystosarcoma phylloides of the breast is presented in whom a full thickness excision of the chest wall was carried out en bloc together with four ribs. The large full-thickness defect of the chest wall was reconstructed with stainless steel mesh and covered by a latissimus dorsi myocutaneous flap. The management of post-operative paradoxical movement is also described. PMID:6313105

  13. A modified pectoralis major myocutaneous flap technique with improved vascular supply and an extended rotation arc for oral defects: A case report

    PubMed Central

    KANNO, TAKAHIRO; NARIAI, YOSHIKI; TATSUMI, HIROTO; KARINO, MASAAKI; YOSHINO, AYA; SEKINE, JOJI

    2015-01-01

    The pedicled pectoralis major myocutaneous (PMMC) flap is versatile, and is widely used for the treatment of surgical defects following oral cancer resection. Although free-tissue transfer of a vascularized free flap is often preferred, the clinical benefits of the PMMC flap should not be overlooked. The conventional technique of harvesting a PMMC flap involves a single vascular supply from the pectoral branch of the thoracoacromial artery. However, this approach compromises the distal skin island of the flap, and requires an indirect blood supply via communicating vessels, which increases the potential risk of partial distal flap necrosis. When harvesting a PMMC flap for oral and maxillofacial reconstruction, preservation of the lateral thoracic artery and use of the subclavian route are alternatives that ensure sufficient blood supply and an increased rotation arc. Such an approach enables the harvesting of a PMMC flap that can reach the entire oral cavity, including the infraorbital region, palate, middle pterygopalatine fossa and nasopharynx, with no risk of vascular insufficiency to the distal skin island. In conclusion, the technique described in the present study was able to improve the blood supply of the distal PMMC flap and increase its rotation arc. PMID:26722234

  14. Quadratus lumborum catheters for breast reconstruction requiring transverse rectus abdominis myocutaneous flaps.

    PubMed

    Spence, Nicole Z; Olszynski, Patrycja; Lehan, Anne; Horn, Jean-Lois; Webb, Christopher A J

    2016-06-01

    Patients diagnosed with breast cancer may opt to undergo surgical reconstructive flaps at the time of or after mastectomies. These surgeries leave patients with significant postoperative pain and sometimes involve large surgical beds including graft sites from the abdomen to reconstruct the breast. Consequently, multimodal methods of pain management have become highly favored. Quadratus lumborum catheters offer an opioid-sparing technique that can be performed easily and safely. We present a case of a patient who underwent a breast flap reconstruction and had bilateral quadratus lumborum catheters placed for perioperative pain control. PMID:26984687

  15. New technical approach for the repair of an abdominal wall defect after a transverse rectus abdominis myocutaneous flap: a case report

    PubMed Central

    Kaemmer, Daniel A; Conze, Joachim; Otto, Jens; Schumpelick, Volker

    2008-01-01

    Introduction Breast reconstruction with autologous tissue transfer is now a standard operation, but abnormalities of the abdominal wall contour represent a complication which has led surgeons to invent techniques to minimize the morbidity of the donor site. Case presentation We report the case of a woman who had bilateral transverse rectus abdominis myocutaneous flap (TRAM-flap) breast reconstruction. The surgery led to the patient developing an enormous abdominal bulge that caused her disability in terms of abdominal wall and bowel function, pain and contour. In the absence of rectus muscle, the large defect was repaired using a combination of the abdominal wall component separation technique of Ramirez et al and additional mesh augmentation with a lightweight, large-pore polypropylene mesh (Ultrapro®). Conclusion The procedure of Ramirez et al is helpful in achieving a tension-free closure of large defects in the anterior abdominal wall. The additional mesh augmentation allows reinforcement of the thinned lateral abdominal wall. PMID:18416835

  16. Reconstruction with a pectoralis major myocutaneous flap after left first rib and clavicular chest wall resection for a metastasis from laryngeal cancer.

    PubMed

    Caronia, Francesco Paolo; Fiorelli, Alfonso; Zanchini, Fabio; Santini, Mario; Lo Monte, Attilio Ignazio; Castorina, Sergio

    2016-05-01

    We presented a case of recurrent metastasis from epidermoid cancer that occurred in the left clavicle of a patient with a history of laryngeal cancer treated on April 2005 with extended hemilaryngectomy, neck dissection and chemoradiation therapy. On September 2008, he developed a left clavicular metastasis. The disease was initially well controlled by chemoradiotherapy but it recurred 17 months later. The optimal treatment plan was established by several multidisciplinary meetings and the patient subsequently underwent an en bloc resection of the left clavicle, first rib and all the other involved structures. Coverage of the thoracic defect was achieved using pectoralis major myocutaneous flap. The patient had a successful surgical outcome. At 1-year follow-up, he had no evidence of disease, a good cosmetic result and returned to normal daily activity. He died for bone metastasis with an overall 21 months post-surgical survival. PMID:25319560

  17. [Myocutaneous latissimus dorsi sliding flap in reconstruction of the lower thoracic wall in chronic fistula caused by cystic echinococcosis of the liver].

    PubMed

    Mouton, W; Schweizer, W; Zuber, J C; Tschopp, H; Blumgart, L H

    1991-07-01

    We report the successful treatment of a 47-year-old man who had a 22-year history of chronic discharge from a hepatic echinococcal cyst. Before treatment in our unit there had been 8 previous attempts to control the fistula. By means of a right thoracoabdominal incision (with resection of the 7th and 8th ribs) it was possible to perform a cystectomy with subsequent marsupialisation of the residual cyst wall to the skin. However, after 2 weeks subsequent treatment with maximal Albendazol therapy there was still a big persistent cavity which required further débridement. This resulted in resolution of the infection and allowed a definitive closure of the big cavity and the thoracoabdominal wall using a myocutaneous latissimus dorsi flap. The patient's subsequent course has been uneventful with no recurrence of the fistula. PMID:1938443

  18. [Evaluation of patients' satisfaction after breast reconstruction with latissimus dorsi myocutaneous flap and immediate permanent breast implant].

    PubMed

    Bognár, Gábor; Gőgh, Bettina; Novák, András; István, Gábor

    2014-04-01

    Current surgical treatment modalities for breast reconstruction include latissimus dorsi mycotaneous flap with immediate permanent breast implant (LDI). The aim of the present study was to analyze reconstruction with LDI in terms of quality of life, cosmesis and patient satisfaction. A chart analysis was carried out with the first ten patients who underwent breast reconstruction with LDI. The patients were interviewed and self-assessment quality of life was administered. They also underwent assessment of satisfaction and cosmesis. The high satisfaction and cosmesis scores in the breast reconstruction group indicate the superior results that can be achieved with breast reconstruction. PMID:24747404

  19. Presurgical Botulinum Toxin A Treatment Increases Angiogenesis by Hypoxia-Inducible Factor-1α/Vascular Endothelial Growth Factor and Subsequent Superiorly Based Transverse Rectus Abdominis Myocutaneous Flap Survival in a Rat Model.

    PubMed

    Park, Tae Hwan; Lee, Song Hyun; Park, Yun Joo; Lee, Young Seok; Rah, Dong Kyun; Kim, Sung Young

    2016-06-01

    To date, there have been several experimental studies to assess tissue viability of transverse rectus abdominis myocutaneous (TRAM) flaps. Botulinum toxin A (BoTA) has gained popularity in many clinical fields, for a variety of therapeutic and aesthetic purposes. In addition, there have been reports regarding the positive effect of BoTA on flap survival by various mechanisms. In this study, we hypothesized that pretreatment with BoTA could augment the survival of TRAM flaps via increased hypoxia-inducible factor (HIF)1α/vascular endothelial growth factor (VEGF)-dependent angiogenesis.Twenty-four Sprague-Dawley rats were randomly divided into 2 groups: a control group and a BoTA group. Five days before superiorly based TRAM flap elevation, the BoTA group was pretreated with BoTA, whereas the control group was pretreated with normal saline. Gross flap survival rates were assessed, and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blotting were performed for the evaluation of angiogenesis-related factors (CD34, HIF-1α, and VEGF).In the BoTA group, the gross flap survival rate was significantly higher than that in the control group on both ipsilateral (92.78.3 ± 5.05% vs 86.8 ± 3.88%, P = 0.009) and contralateral (91.57 ± 5.79% vs 74.28 ± 11.83%, P < 0.001) sides.The relative mRNA expression of CD34 and VEGF was significantly higher in the BoTA group than that in the control group in every zone, whereas the relative mRNA expression of HIF-1α was significantly higher in the BoTA group than that in the control group on contralateral sides. The relative protein expression of CD34, VEGF, and HIF-1α was significantly higher in the BoTA group than that in the control group in every zone.In conclusion, we demonstrate that presurgical BoTA treatment might increase angiogenesis by HIF-1α/VEGF, subsequently increase superiorly based TRAM flap survival in a rat model. PMID:25695458

  20. Use of Latissimus Dorsi Pedicled Myocutaneous Flap for Reconstruction in the Chest Area of an 8-Month-Old Female Infant with Ectopia Cordis

    PubMed Central

    Dastagir, Khaled; Breymann, Thomas; Heckmann, Andreas; Horke, Alexander; Vogt, Peter Maria

    2014-01-01

    Ectopia cordis (EC) is characterized by a complete or partial malposition of the heart outside the thorax. Despite the interdisciplinary treatment, the repair of EC is still very difficult and offers new surgical challenges because of its complexity and various combinations with other anomalies. We report the successful outcome after using a pedicled latissimus dorsi flap in reconstructive surgery in the setting of chronic wound dehiscence in an 8-month-old female infant born with a thoracic EC and omphalocele. PMID:25798359

  1. Management of giant inferior triangle lumbar hernia (Petit's triangle hernia): A rare complication following delayed breast reconstruction with extended latissimus dorsi myocutaneous flap

    PubMed Central

    Munhoz, Alexandre Mendonça; Montag, Eduardo; Arruda, Eduardo Gustavo; Sturtz, Gustavo; Gemperli, Rolf

    2014-01-01

    INTRODUCTION Lumbar triangle hernia after breast reconstruction with latissimus dorsi flap (LDMF) is a very rare complication and few cases were previously described. Muscle mobilization and iatrogenic fascia defect are related etiologic factors. PRESENTATION OF CASE The authors describe a rare case of lumbar hernia in a 58-year-old woman who underwent delayed left breast reconstruction with LDMF. Two months after surgery, a progressive symptomatic lower left lumbar bulge was observed. The CT scan confirmed the diagnosis and delineated an 18 cm lumbar defect filled with lower and large bowel. At operation, the defect was exposed and the hernia sac reduced. In order to obtain stability, the remained local muscle and fascia flaps were mobilized into the defect. Additional strength was achieved with a two-layer closure of prosthetic mesh (intra/extra peritoneal). The patient is currently in the 10th postoperative year of hernia repair and satisfactory lumbar wall contour was achieved. Neither the recurrence of lumbar hernia nor symptoms compliance was noted. DISCUSSION Lumbar hernia is an uncommon complication of LDMF harvest. Although it is a rare disease, general and plastic surgeons must be on alert to avoid complications and misdiagnosis. Seroma differential diagnosis is important in order to avoid bowel perforation due to aspiration. Defect reconstruction is necessary with a muscular and fascia flaps mobilization and synthetic mesh in order to obtain a stable repair. CONCLUSION The knowledge of this rare post-operative complication following delayed breast reconstruction is crucial to its surgical management. Early surgical intervention is warranted in order to avoid severe complications. PMID:24794025

  2. [Immediate vaginal reconstruction with a musculocutaneous flap from the gracilis muscle after extended abdomino-perineal resection].

    PubMed

    Sezeur, A; Hautefeuille, P; Trevidic, P

    1995-01-01

    Reconstruction of a functional vagina after radical abdomino-perineal resection is a difficult surgical problem. The use of the gracilis myocutaneous flap provides a satisfactory solution. This article describes the surgical procedure of immediate vaginal reconstruction using the gracilis myocutaneous flap. Unfortunately, this technique is still not widely used by surgical teams. Nevertheless, it is a useful flap because of its low morbidity and the satisfying result of the functional neovaginal cavity. PMID:8526447

  3. Keyhole Flap Nipple Reconstruction

    PubMed Central

    Cash, Camille G.; Iman, Al-Haj; Spiegel, Aldona J.; Cronin, Ernest D.

    2016-01-01

    Summary: 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.

  4. 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

  5. [Flap-reconstruction in mouth and oropharynx. A clinical comparison of methods (author's transl)].

    PubMed

    Eitschberger, E; Weidenbecher, M

    1981-10-01

    The possible methods for plastic reconstruction after resection of malignant tumors in the mouth and oropharynx are reported. A total of 165 patients, operated upon between 1973 and 1980, has been reviewed. The tumor was located 26 times in the tongue, 4 times within the base of the tongue, 27 times in the floor of the mouth, 10 times in the floor of the mouth and in the tongue and 80 times in the tonsils. For reconstruction 8 times the deltopectoral flap, 51 times the forehead flap, 42 times the tongue flap, 7 times the myocutaneous sternocleido-mastoideus island flap were used. 8 times other methods were applied, like for instance skin grafts, and in 41 cases a primary closure of the defect was possible. Complete necrosis of the flap were rare, more frequent in contrast were partial dehiscences with or without a fistula. Thus in the forehead flap 5 times a necrosis occurred whereas in 15 cases a dehiscence was seen. Even better results were achieved for the deltopectoral- and tongue flap. In contrast, the skin island of the myocutaneous sternocleidomastoideus flaps all became necrotic, but only once a temporary fistula developed. Of the pectoralis myocutaneous island flaps the first two became necrotic, probably due to lack of surgical experience. Taking into account the surgical expenditure, the functional as well as cosmetical results, the methods may be scaled according to clinical value as follows: The pectoralis major myocutaneous island flap and the tongue flap equally range on the first place, followed by the myocutaneous sternocleidomastoideus island flap, and on the 3. and 4. place by the deltopectoral and forehead flap. PMID:7287523

  6. [The gracilis muscle as musculocutaneous flap. Evaluation of 20 cases].

    PubMed

    Gholam, D; Trevidic, P; Kleimann, P; Hautefeuille, P; Nicoletis, C

    1991-01-01

    The use of gracilis as muscular or myocutaneous flap is very well-known. The authors report 20 cases of gracilis flap including 13 reconstructions of the vaginal cavity following extended abdomino-perineal resection. Some technical points concerning the localization of the cutaneous part of the flap and the pedicle dissection are discussed. The use of gracilis flap is still limited in surgical teams following extended abdomino-perineal resection, nevertheless it is a very useful flap because of its low morbidity, the shortening of patient hospitalization and the very satisfying aesthetic result of the neo-vaginal cavity. PMID:1726389

  7. 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

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

    PubMed

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

    2016-01-01

    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

  9. Platysma flap using dual skin paddles.

    PubMed

    Mustafa, El Muiz A; Bhatia, Sunil K; Hammond, Doug E

    2016-07-01

    The platysma myocutaneous flap is rarely reported as an option for reconstruction in the head and neck. In our experience it is a reliable flap that is easy to raise, has a limited risk of morbidity at the donor site, and allows for early recommencement of oral function. We report a patient with an unusually aggressive orocutaneous fistula that complicated the simple extraction of teeth. We modified the platysma flap to provide two independent skin paddles so we could reconstruct both the intraoral and cutaneous defects simultaneously with a good clinical outcome. PMID:26947107

  10. Reconstruction Using Locoregional Flaps for Large Skull Base Defects.

    PubMed

    Hatano, Takaharu; Motomura, Hisashi; Ayabe, Shinobu

    2015-06-01

    We present a modified locoregional flap for the reconstruction of large anterior skull base defects that should be reconstructed with a free flap according to Yano's algorithm. No classification of skull base defects had been proposed for a long time. Yano et al suggested a new classification in 2012. The lb defect of Yano's classification extends horizontally from the cribriform plate to the orbital roof. According to Yano's algorithm for subsequent skull base reconstructive procedures, a lb defect should be reconstructed with a free flap such as an anterolateral thigh free flap or rectus abdominis myocutaneous free flap. However, our modified locoregional flap has also enabled reconstruction of lb defects. In this case series, we used a locoregional flap for lb defects. No major postoperative complications occurred. We present our modified locoregional flap that enables reconstruction of lb defects. PMID:26225296

  11. 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

  12. Microsurgical free flaps: Controversies in maxillofacial reconstruction

    PubMed Central

    George, Rinku K.; Krishnamurthy, Arvind

    2013-01-01

    Reconstructive microsurgery for oral and maxillofacial (OMF) defects is considered as a niche specialty and is performed regularly only in a handful of centers. Till recently the pectoralis major myocutaneous flap (PMMC) was considered to be the benchmark for OMF reconstruction. This philosophy is changing fast with rapid advancement in reconstructive microsurgery. Due to improvement in instrumentation and the development of finer techniques of flap harvesting we can positively state that microsurgery has come of age. Better techniques, microscopes and micro instruments enable us to do things previously unimaginable. Supramicrosurgery and ultrathin flaps are a testimony to this. Years of innovation in reconstructive microsurgery have given us a reasonably good number of very excellent flaps. Tremendous work has been put into producing some exceptionally brilliant research articles, sometimes contradicting each other. This has led to the need for clarity in some areas in this field. This article will review some controversies in reconstructive microsurgery and analyze some of the most common microvascular free flaps (MFF) used in OMF reconstruction. It aims to buttress the fact that three flaps-the radial forearm free flap (RFFF), anterolateral thigh flap (ALT) and fibula are the ones most expedient in the surgeon's arsenal, since they can cater to almost all sizeable defects we come across after ablative surgery in the OMF region. They can thus aptly be titled as the workhorses of OMF reconstruction with regard to free flaps. PMID:23662264

  13. 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

  14. Maintenance of the spinal nucleus of the bulbocavernosus neuromuscular system is not influenced by physiological levels of glucocorticoids.

    PubMed

    Niel, Lee; Alves, Philip A; Pinzon, Natalia; Holmes, Melissa M; Lovern, Matthew B; Monks, D Ashley

    2012-08-01

    The spinal nucleus of the bulbocavernosus (SNB) neuromuscular system mediates sexual reflexes, and is highly sexually dimorphic in rats. While maintenance of this system in adulthood is mainly dependent on androgens, there is also evidence to suggest that glucocorticoids may have a catabolic effect. We conducted a series of studies to fully examine the influence of basal glucocorticoids on the size of the SNB motoneurons and the associated bulbocavernosus (BC) and levator ani (LA) muscles. Specifically, we examined whether the muscles and motoneurons of the SNB neuromuscular system are affected by: (1) blockade of endogenous glucocorticoids via delivery of the antagonist RU-486 at doses ranging from low to high, (2) removal of endogenous glucocorticoids via adrenalectomy, or (3) restoration of physiological corticosterone levels via implants following adrenalectomy. In each study, we found that muscle and motoneuron size were unaffected by glucocorticoid manipulation. In contrast to previous results with supraphysiological levels of glucocorticoids, our results indicate that basal, nonstress levels of glucocorticoids do not influence the size of the BC/LA muscles or their associated SNB motoneurons. PMID:21412989

  15. Free Flap Reconstruction for Complex Scalp and Forehead Defects with Associated Full-Thickness Calvarial Bone Resections

    PubMed Central

    Larrañaga, Juan; Rios, Alfredo; Franciosi, Edgardo; Mazzaro, Eduardo; Figari, Marcelo

    2012-01-01

    Extensive defects of the scalp and forehead associated with calvarial bone resections demand complex reconstructions. Free flaps offer vascularized tissue of excellent quality and quantity. We report six patients with extensive scalp and forehead defects associated with calvarial bone resections reconstructed with free flaps. Five patients also required a cranioplasty. The flaps used were two anterolateral thigh flaps, one vastus lateralis flap, one myocutaneous latissimus dorsi flap, one latissimus dorsi flap, and one radial forearm flap. All flaps survived with no partial necrosis. There were no donor site complications. One patient presented an exposure of the alloplastic material used for cranioplasty. We strongly recommend the use of free flaps for this kind of reconstruction. PMID:24294403

  16. [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. PMID:9768175

  17. Pedicled Breast Flap for Soft Tissue Coverage of a Forearm Blast Injury

    PubMed Central

    Zuriarrain, Alexander; Brooks, Christopher

    2016-01-01

    Summary: This article presents the case of a 35-year-old woman who sustained a shotgun blast injury to the left forearm and chest wall causing significant soft tissue loss of the extensor compartment. The patient suffered a Gustilo IIIB open radial shaft fracture requiring orthopedic stabilization and plastic surgery intervention. As a result, the patient eventually was reconstructed with the use of a pedicled breast flap. Because of the patient’s macromastia and her large forearm wound and morbid obesity, an individualized approach was developed such that a breast flap was designed because of its proximity to the upper extremity. The advantage of this type of reconstruction is a more natural contour to the forearm with minimal donor site morbidity. Before creation of the flap, the patient expressed interest in a reduction mammaplasty because of her symptomatic macromastia. Overall, this was a 2-step operation whereby first the breast flap was created, and then a few weeks later, once the arm healed, the reduction mammaplasty was performed. Other types of flaps for upper extremity reconstruction include the rectus abdominis myocutaneous, transverse rectus abdominis myocutaneous, vertical rectus abdominis myocutaneous, groin, and latissumus dorsi. The pedicled breast flap is an innovative approach to upper extremity soft tissue coverage and can be tailored to the specific needs of patients similar to our case presentation. PMID:27104108

  18. 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

  19. 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

  20. 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.

  1. Coverage of Amputation Stumps Using a Latissimus Dorsi Flap With a Serratus Anterior Muscle Flap: A Comparative Study.

    PubMed

    Kim, Sang Wha; Jeon, Seung Bae; Hwang, Kyu Tae; Kim, Youn Hwan

    2016-01-01

    Amputation of the extremities is a definitive reconstructive option, and surgeons should aim to preserve maximum overall function. If the exposed bone cannot be adequately covered using local tissues, the stump can be reconstructed using a number of well-described free flap transfer techniques. Between January 2002 and December 2011, 31 patients with severe injuries to the lower extremities underwent above-the-knee, below-the-knee, and Chopart and Ray amputations. Bony stumps were covered using latissimus dorsi myocutaneous flaps alone (group 1), or together with serratus anterior muscle flaps (group 2). The groups were compared with respect to age, flap survival, skin flap size, immediate complications, wound sloughing, deep ulceration, need for bone amputation, limb visual analog scale score, time to prosthesis, and follow-up duration. The mean area of the latissimus dorsi skin flap was 255.9 cm, and immediate complications occurred in 8 (25.8%) patients. In the double-padding group, there were fewer cases of deep ulceration than in the single-flap group, and prostheses could be worn sooner. There were no statistically significant differences in other parameters. Successful reconstruction of amputation stumps requires an adequate, durable, weight-bearing, and well-contoured soft tissue cover. A latissimus dorsi musculocutaneous flap together with a serratus anterior muscle flap provides well-vascularized muscle tissue and a durable skin paddle, leading to less ulceration than conventional flap techniques. PMID:25003415

  2. Vaginal reconstruction with pedicled vertical deep inferior epigastric perforator flap (diep) after pelvic exenteration. A consecutive case series.

    PubMed

    Ferron, Gwénael; Gangloff, Dimitri; Querleu, Denis; Frigenza, Melanie; Torrent, Juan Jose; Picaud, Laetitia; Gladieff, Laurence; Delannes, Martine; Mery, Eliane; Boulet, Berenice; Balague, Gisele; Martinez, Alejandra

    2015-09-01

    Vaginal reconstruction after pelvic exenteration (PE) represents a challenge for the oncologic surgeon. Since the introduction of perforator flaps, using pedicled vertical DIEP (deep inferior epigastric perforator) flap allows to reduce the donor site complication rate. From November 2012 to December 2014, 27 PEs were performed in our institution. 13 patients who underwent PE with vaginal reconstruction and programmed DIEP procedure for gynecologic malignancies were registered. Nine patients underwent PE for recurrent disease and four for primary treatment. Six of the 13 patients have a preoperative fistula. Anterior PE was performed in 10 patients, and total PE in 3 patients. A vertical DIEP flap was performed in 10 patients using one or two medial perforators. The reasons for abortion of vertical DIEP flap procedure were: failure to localizing perforator vessels in two cases, and unavailability of plastic surgeon in one case. A vertical fascia-sparring rectus abdominis myocutaneous flap was then harvested. Median length of surgery was 335min, and 60min for DIEP harvesting and vaginal reconstruction. No flap necrosis occurred. One patient in the VRAM (vertical rectus abdominis myocutaneous) group experienced a late incisional hernia and one patient in the DIEP flap group required revision for vaginal stenosis. In our experience, DIEP flap represents our preferred choice of flap for circumferential vaginal reconstruction after PE. To achieve a high reproducibility, the technically demanding pedicled vertical DIEP flap has to be harvested by a trained surgeon, after strict evaluation of the preoperative imaging with identification and localization of perforator vessels. PMID:26121919

  3. Extended V-Y Advancement Flap Reconstruction of a Large Posterior Upper Midline Trunk Defect

    PubMed Central

    Fukudome, Eugene Y.; Bharadia, Deepak R.; Helm, Douglas L.

    2016-01-01

    Summary: Large posterior upper trunk defects can be challenging to reconstruct. Trapezius or latissimus dorsi myocutaneous flaps are principally utilized for reconstruction; however, some defects may not be amenable to this standard approach. Here, we describe a patient with a full-thickness skin and subcutaneous tissue loss of the upper back and inferior cervical region after dermatofibrosarcoma protuberans resection. A large, extended V-Y flap was used for closure of this wound secondary to its location, size, and orientation. This approach preserves shoulder function, allows for readvancement of the flap as needed, and is a reconstructive option for patients with large upper back defects.

  4. Extended V-Y Advancement Flap Reconstruction of a Large Posterior Upper Midline Trunk Defect.

    PubMed

    Fukudome, Eugene Y; Bharadia, Deepak R; Helm, Douglas L; Sinha, Indranil

    2016-05-01

    Large posterior upper trunk defects can be challenging to reconstruct. Trapezius or latissimus dorsi myocutaneous flaps are principally utilized for reconstruction; however, some defects may not be amenable to this standard approach. Here, we describe a patient with a full-thickness skin and subcutaneous tissue loss of the upper back and inferior cervical region after dermatofibrosarcoma protuberans resection. A large, extended V-Y flap was used for closure of this wound secondary to its location, size, and orientation. This approach preserves shoulder function, allows for readvancement of the flap as needed, and is a reconstructive option for patients with large upper back defects. PMID:27579237

  5. Return of lymphatic function after flap transfer for acute lymphedema.

    PubMed Central

    Slavin, S A; Van den Abbeele, A D; Losken, A; Swartz, M A; Jain, R K

    1999-01-01

    OBJECTIVE: The goals of this work were to develop animal models of lymphedema and tissue flap transfer, and to observe physiologic changes in lymphatic function that occur in these models over time, both systemically with lymphoscintigraphy (LS) and locally using fluorescence microlymphangiography (FM). SUMMARY BACKGROUND DATA: Although lymphedema has been managed by a combination of medical and surgical approaches, no effective long-term cure exists. Surgical attempts aimed at reconnecting impaired lymphatic channels or bypassing obstructed areas have failed. METHODS: The tails of rats (A groups) and mice (B groups) were used because of their different features. Lymphedema was created by ligation of the lymphatics at the tail base and quantified by diameter measurements there. In the experimental group, rectus abdominis myocutaneous flap was transferred across the ligation. In addition to the ligation (A1 and B1) and ligation + flap (A2 and B2) groups, three control groups were included: sham flap with ligation (B4), sham flap alone (B5), and normal (A3 and B3) animals. Observations were made at weekly time points for lymphatic function and continuity. RESULTS: Lymphedema was successfully created in the mouse ligation groups (B1 and B4) and sustained for the entire length of observation (up to 14 weeks). Lymphatic continuity was restored in those animals with transferred flaps across the ligation site (A2 and B2), as seen both by LS and FM. Sham flaps did not visibly affect lymphatic function nor did they cause any visible swelling in the tail. CONCLUSIONS: Acute lymphedema developing after ligation of tail lymphatics in mice can be prevented by myocutaneous flap transfer. Restored lymphatic continuity and function were demonstrable using lymphoscintigraphy and fluorescence microlymphangiography. Images Figure 2. Figure 4. Figure 5. PMID:10077056

  6. 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. PMID:26421478

  7. Predictive risk factors of free flap thrombosis in breast reconstruction surgery.

    PubMed

    Masoomi, Hossein; Clark, Emily G; Paydar, Keyianoosh Z; Evans, Gregory R D; Nguyen, Audrey; Kobayashi, Mark R; Wirth, Garrett A

    2014-11-01

    Vascular thrombosis is one of the major postoperative complications of free flap microvascular breast reconstruction operations. It is associated with higher morbidity, higher cost, increased length of hospital stay, and potentially flap loss. Our purpose is to evaluate the rate of this complication and whether patient characteristics play a role. Using the Nationwide Inpatient Sample (NIS) database, we examined the clinical data of patients who underwent free flap breast reconstruction between 2009 and 2010 in the United States. Multivariate and univariate regression analyses were performed to identify independent risk factors of flap thrombosis. A total of 15,211 patients underwent free flap breast reconstruction surgery (immediate reconstruction: 43%). The most common flap was the free deep inferior epigastric perforator (DIEP) flap (53.6%), followed by free transverse rectus abdominis myocutaneous (TRAM) flap (43.1%), free superficial inferior epigastric artery (SIEA) flap (2%), and free gluteal artery perforator (GAP) flap (1.3%). The overall rate of flap thrombosis was 2.4 %, with the highest rate seen in the SIEA group (11.4%) and the lowest in the TRAM group (1.7%). Peripheral vascular disease (adjusted odds ration [AOR] 10.61), SIEA flap (AOR, 4.76) and delayed reconstruction (AOR, 1.42) were found to be statistically significant risk factors for flap thrombosis. Other comorbidities were not linked. While the overall rate of flap thrombosis in free flap breast reconstruction was relatively low (2.4%), Plastic Surgeons should be aware that patients with peripheral vascular disease and those undergoing free SIEA flap are at higher risk of flap thrombosis and they should closely monitor flaps to increase the chance for early salvage. PMID:24665051

  8. What Is the Ideal Free Flap for Soft Tissue Reconstruction? A Ten-Year Experience of Microsurgical Reconstruction Using 334 Latissimus Dorsi Flaps From a Universal Donor Site.

    PubMed

    Kim, Jeong Tae; Kim, Sang Wha; Youn, Seungki; Kim, Youn Hwan

    2015-07-01

    Microsurgical free tissue transfer is regarded as the best available method of tissue reconstruction for intractable defects. The ideal soft tissue flap is thought to be the anterolateral thigh flap. On the basis of 334 procedures involving the latissimus dorsi (LD) flap, we discuss the advantages of the LD flap over the current universal option, and we aimed to establish whether the LD could also gain universal status in all reconstructive fields.Three hundred thirty-four reconstructive procedures using the LD flap were performed in 322 patients between September 2002 and July 2012. In accordance with defect characteristics, we performed 334 procedures using flaps, which included the LD muscle flap with skin graft, the myocutaneous flap, the muscle-sparing flap, the perforator flap, the chimeric flap, and the 2-flap technique using the serratus anterior branch.Flap-related complications occurred in 21 patients (6.3%), including total and partial flap failure. In 253 cases, the donor site was closed primarily, and in the remaining cases, we used split-thickness skin grafts. Donor-site complications occurred in 20 cases (6%). In 11 of the 182 cases, no suitable perforators were identified during surgery.The advantages of the LD as a donor site include the possibility of various harvesting positions without position change, versatility of components, availability of muscle to fill extensive defects, and presence of thick fascia to enable full abdominal reconstruction. On the basis of our experience, we concluded that this flap has the potential to be used as widely as, or in preference to, the anterolateral thigh flap in most reconstructive areas. PMID:25785382

  9. 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. PMID:25801799

  10. Abdominal perforator vs. muscle sparing flaps for breast reconstruction

    PubMed Central

    Wu, Liza C.

    2015-01-01

    Abdominally based free flaps have become the mainstay for women that desire to use their own tissue as a means of breast reconstruction after mastectomy. As the techniques have evolved, significant effort has been invested in finding the best means of minimizing morbidity to the abdominal donor site while ensuring a viable reconstructed breast that is aesthetically pleasing. This manuscript reviews and compares the muscle sparing free transverse rectus abdominis myocutaneous (MsfTRAM), the deep inferior epigastric artery perforator (DIEP), and the superficial inferior epigastric artery (SIEA) flaps, regarding flap success rate, operative times, abdominal donor site morbidity and residual functionality, hospital lengths of stay and associated costs, impact of co-morbid conditions, and resilience after adjuvant radiation treatment. PMID:26161306

  11. Abdominal perforator vs. muscle sparing flaps for breast reconstruction.

    PubMed

    Butler, Paris D; Wu, Liza C

    2015-06-01

    Abdominally based free flaps have become the mainstay for women that desire to use their own tissue as a means of breast reconstruction after mastectomy. As the techniques have evolved, significant effort has been invested in finding the best means of minimizing morbidity to the abdominal donor site while ensuring a viable reconstructed breast that is aesthetically pleasing. This manuscript reviews and compares the muscle sparing free transverse rectus abdominis myocutaneous (MsfTRAM), the deep inferior epigastric artery perforator (DIEP), and the superficial inferior epigastric artery (SIEA) flaps, regarding flap success rate, operative times, abdominal donor site morbidity and residual functionality, hospital lengths of stay and associated costs, impact of co-morbid conditions, and resilience after adjuvant radiation treatment. PMID:26161306

  12. Extending the use of the gracilis muscle flap in perineal reconstruction surgery.

    PubMed

    Goldie, Stephen J; Almasharqah, Riyadh; Fogg, Quentin A; Anderson, William

    2016-08-01

    Reconstruction of the perineum is required following oncological resections. Plastic surgical techniques can be used to restore the aesthetics and function of the perineum. The gracilis myocutaneous flap provides a substantial skin paddle, with minimal donor site morbidity. The flap is pedicled on a perforator from the medial circumflex femoral artery, giving it limited reach across the perineum. Tunnelling the flap under the adductor longus muscle may free up more of the arterial pedicle, increasing its reach. On three female cadavers, bilateral gracilis flaps were raised in the standard surgical manner, giving six flaps in total. With the flaps pedicled across the perineum, the distance from the tip of each flap was measured to the anterior superior iliac spine (ASIS). The flaps were then tunnelled under the adductor longus muscle. The distances to the ASIS were measured again. The average pedicle length was greater than 7 cm. Tunnelling the flap under the adductor longus muscle increased the reach by more than 4 cm on average. Cadaveric dissection has shown that tunnelling of the flap in a novel way increase its reach across the perineum. This additional flexibility improves its use clinically and is of benefit to plastic surgeons operating in perineal reconstruction. PMID:27221783

  13. 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

  14. Scars and perforator-based flaps in the abdominal region: A contraindication?

    PubMed Central

    Dragu, Adrian; Unglaub, Frank; Wolf, Maya B.; Beier, Justus P.; Schnabl, Saskia M.K.; Kneser, Ulrich; Leffler, Mareike; Horch, Raymund E.

    2010-01-01

    Background Although multiple strategies for autologous breast reconstruction exist, a vertical midline scar in the abdominal wall as a result of previous laparatomy or abdominoplasty represents a major surgical challenge. To date, little research has been conducted on the regeneration potential of the abdominal wall’s superficial vascular, perforator and choke vessel system after surgery using a vertical approache. Methods We present the cases of 8 patients, of whom 7 underwent autologous breast reconstruction. One patient received a thigh reconstruction. All patients had a vertical abdominal midline scar as a result of a previous surgical intervention. In 3 of the 7 patients, the breast was reconstructed using an MS-2-vertical rectus abdominis myocutaneous (VRAM) free flap. In 4 of these patients, an MS-2-transverse rectus abdominis myocutaneous (TRAM) free flap was performed. The thigh reconstruction used a transverse deep inferior epigastric perforator (DIEP) free flap. Clinical follow-up was done 12 months after operation. Results All 3 patients who received an MS-2-VRAM had good aesthetic results. Vertical midline scars had no negative effect on surgical outcomes, perfusion and tissue viability of the 4 MS-2-TRAM and transverse DIEP free flaps. Conclusion These clinical findings indicate that the regeneration potential of the abdominal wall’s superficial vascular system in the presence of vertical surgical scars has been greatly underestimated. Use of MS-2-VRAM free flaps in patients with vertical abdominal scars seems to be a suitable and successful alternative in the reconstruction algorithm. PMID:20334747

  15. [Repair of large urogenital necrosis of obstetrical origin by pedicled myocutaneous plasty of the greater lip. Technique and results].

    PubMed

    Falandry, L

    1991-03-01

    The vesicovaginal fistulae encountered in Africa are a real plague. Their origin is obstetrical as a rule, and they occur in young women, often in primiparas. They are seldom simple as they have been operated repeatedly and involve associated lesions and a large loss of substance, so that they raise complex problems of repair. The experience with the treatment of 230 obstetrical fistulae by the same surgeon in Africa leads the author to describe a repair technique fit for complex fistulae, especially those involving an extensive loss of substance and associated lesions (rectovaginal fistula, perineal destruction). With a low approach, the procedure consists in using a filler tissue, namely a skin flap removed from a greater lip, for which the vasculature is maintained by the preservation of a thick musculous and fatty pedicle, cut from the fibers of the bulbocavernosus muscle. Once sutured around the orifice of the fistula, this graft closes it while fostering its healing. Out of the 14 patients treated with this technique, the results achieved were regarded as good for 10 (72%), including 7 after a first operation and 3 after second surgery. In 9 cases, there were associated lesions, including 5 rectovaginal fistulae and 4 cases of complete tearing of the perineum. We have had 4 failures, including 3 definitive ones, and a partial failure with the persistence of urine incontinence in station due to be destruction of the ureter. When the simpler Martius' procedure (on which ours is patterned) is no longer sufficient, the use of a pedicled skin-fat graft taken from the greater lip allows considerably restricting the indications of palliative surgery. Our technique increases the percentage of success for fistulae regarded as irreparable or after the usual repair procedures have failed. PMID:2055973

  16. Peculiar indications for the pedicled or free rectus abdominis flap in reconstructive surgery. A review of our experience.

    PubMed

    Sinsel, N K; Guelinckx, P J

    1995-01-01

    Among all known flaps, the rectus abdominis muscle flap possesses an unique diversity in flap designs due to the special vascular supply of the abdominal wall. The axial vascularization of the rectus abdominis muscle gives ofF several musculocutaneous perforators, which are mainly located in the periumbilical region. Abdominal wall skin perfusion is guaranteed by spoke-wheel like vessels arising from these perforators. Subsequently several designs (muscle, myocutaneous and myosubcutaneous) are possible, by varying the included tissue and the position of the skin island. We described 7 cases where the rectus abdominis muscle was used as a muscle or myocutaneous flap for reconstruction of large defects. In most cases a pedicled transfer was necessary, possible and sufficient to reconstruct the difficult defects in various body regions. Great amounts of well perfused tissue can be transferred with still possible primary closure of the donor site. Due to its rich perfusion and constancy of vascular pattern, it represents an excellent and safe pedicled reconstructive procedure for large defects of the thorax, the abdomen, the forearm or the hip and pelvis where free tissue transfers are impossible or contraindicated. No other local transposition would have achieved this goal, due to the lack of volume and mobility. Moreover the flap is ideal for reconstruction of contour deficiencies due to the abundance of fat, as for example in breast or buttock reconstruction. However the flap is not the first choice for traumatic and infected wounds where fat tissue is not desired. PMID:8571724

  17. Vascular Endothelium Growth Factor, Surgical Delay, and Skin Flap Survival

    PubMed Central

    Lineaweaver, William C.; Lei, Man-Ping; Mustain, William; Oswald, Tanya M.; Cui, Dongmei; Zhang, Feng

    2004-01-01

    Objective: Cytokines may be a mechanism by which surgical delay can increase flap survival. We previously found that preoperative vascular endothelium growth factor (VEGF) administration in the rat transverse rectus abdominis myocutaneous (TRAM) flap could improve skin paddle survival. In this study, we used partial elevation of the rat TRAM flap as a surgical delay to assess endogenous cytokine expression and tissue survival comparable to undelayed TRAM flaps. Methods: In Part I, TRAM flaps underwent surgical delay procedures; 7 days later, the flaps were completely elevated and reinset. At the same time, other flaps were raised and reinset without delay. Skin paddle survival in both groups was evaluated at 7 days. In Part II, skin biopsies from TRAM zones I to IV were taken at the time of delay and at intervals of 12, 24, 48, and 72 hours. Specimens were assessed for selected cytokine gene expression by reverse transcription-polymerase chain reaction analysis (TR-PCR). Results: Surgical delay significantly (P < 0.001) increased skin paddle survival in the delayed TRAM flaps (16.14 ± 1.53 cm, 81.9%) compared with undelayed flaps (7.68 ± 3.16 cm, 40.9%). TGF-β and PDGF expressions were not changed by surgical delay, but basic fibroblast growth factor (bFGF) and VEGF expressions increased significantly (P < 0.05 and P < 0.01) after delay. Conclusions: In the rat TRAM model, surgical delay resulted in increased VEGF expression and increased skin paddle survival. These results correlate with previous studies showing the preoperative injection of VEGF increases skin paddle survival. VEGF may be an important element in the delay phenomenon and may be an agent for pharmacological delay. PMID:15166966

  18. Management of different kinds of head and neck defects with the submental flap for reconstruction.

    PubMed

    Tsai, Wan-Chun; Yang, Jinn-Moon; Liu, Shao-Cheng; Chu, Yueng-Hsiang; Lai, Wen-Sen; Lin, Yaoh-Shiang; Lee, Jih-Chin

    2015-12-01

    Head and neck surgeries often accompany with moderate-sized defects that require time-consuming reconstructions by free flaps. The submental flap is a versatile and time-effective option for reconstruction of orofacial defects providing acceptable cosmetic and functional results without requiring microsurgical techniques. A retrospective case series study of patients who underwent reconstruction with the submental flap between 2009 and 2013 was conducted. There were 36 patients (33 men and 3 women), with a mean age of 56.4 years, enrolled in this study. The primary lesion sites included oral cavity (24 patients), pharynx (8 patients), larynx (2 patients), neck (1 patient) as well as maxillary sinus (1 patient). All flaps were harvested as the myocutaneous flaps. All donor sites were closed primarily without the need of additional surgery. No complete loss of the flap was encountered and two cases developed marginal necrosis of the flap. The submental flap had a reliable pedicle and had minimal donor-site morbidity. It is an excellent flap option for patients with small- to medium-sized defects in head and neck region. PMID:25542248

  19. Surgical Approach for Repair of Rectovaginal Fistula by Modified Martius Flap

    PubMed Central

    Reichert, M.; Schwandner, T.; Hecker, A.; Behnk, A.; Baumgart-Vogt, E.; Wagenlehner, F.; Padberg, W.

    2014-01-01

    Rectovaginal fistulas (RVF) are rare but represent a challenge for both patients and surgeons. The most common cause of RVF is obstetric trauma, and treatment is based on fistula classification and localization of the fistula in relation to the vagina and rectum. Conventional therapy frequently fails, making surgery the most viable approach for fistula repair. One surgical procedure which offers adequate repair of lower and middle rectovaginal fistulas consists of interposition of a bulbocavernosus fat flap also called modified Martius flap. First described by Heinrich Martius in 1928, this approach has been continuously modified and adjusted over time and is used in the repair of various pelvic floor disorders. Overall success rates reported in the literature of the interposition of a Martius flap as an adjunct procedure in the surgical management of RVF are 65–100 %. We present a detailed description of the operation technique together with a discussion of the use of a dorsal-flapped modified Martius flap in the treatment of RVF. PMID:25364031

  20. Reconstruction of the pelvis and perineum with a free latissimus dorsi myocutaneous flap: a case report.

    PubMed

    Kieran, I; Nugent, N; Riordain, M Ó; Kelly, J

    2012-11-01

    Reconstruction of the perineum and pelvic cavity in continuity is an uncommon and difficult challenge. This case describes a 66-year-old man who presented following recurrence of a Dukes' B rectosigmoid adenocarcinoma that had been treated nine years previously by anterior resection, 5-fluorouracil and radiotherapy. His recurrent disease was treated with radical pelvic exenteration with formation of an end colostomy and urinary ileal conduit. A post-operative pelvic collection necessitated incisional drainage via the perineum. This resulted in a perineal defect in continuity with the pelvic cavity, neither of which healed in spite of alternate day packing with antiseptic dressings. The perineum and cavity were reconstructed successfully with a microvascular transfer of the latissimus dorsi using the primary gracilis pedicle as recipient donor vessels. PMID:23131218

  1. Resection and reconstruction of giant cervical metastatic cancer using a pectoralis major muscular flap transfer: A prospective study of 16 patients

    PubMed Central

    ZHANG, XIANGMIN; LIU, FOLIN; LAN, XIAOLIN; HUANG, JING; LUO, KEQING; LI, SHAOJIN

    2015-01-01

    If not promptly or properly treated, certain cervical metastatic cancers that develop from unknown primary tumors may rapidly grow into giant tumors that can invade the blood vessels, muscle and skin. The present study examined the feasibility and efficacy of radical neck dissection combined with reconstruction using the pectoralis major myocutaneous flap for the treatment of giant cervical metastatic cancers that have developed from unknown primary tumors and have invaded the skin. A total of 16 patients who met the inclusion criteria were subjected to radical neck dissection to adequately resect invaded skin, and the pectoralis major myocutaneous flap was used to repair the large skin defect created in the cervical region. Following the surgery, the patients received concurrent chemoradiotherapy. The pectoralis major myocutaneous flap survived in all 16 patients, with no cases of flap necrosis. In addition, no post-operative lymphedema, paresthesia or dysfunction of an upper extremity occurred due to the cutting of a pectoralis major muscle. In 9 cases, patients were satisfied with their post-operative shoulder movement at the donor site; in the remaining 7 cases, patients felt greater weakness in this region following surgery relative to prior to surgery. The 14 male patients were generally satisfied with the post-operative appearance of the donor region, whereas the 2 female patients were dissatisfied with the appearance of this region. Follow-up for 6–53 months after the patients were discharged following surgery and chemotherapy revealed that the recurrence of cervical tumors in 6 cases. Overall, radical neck dissection combined with the use of the pectoralis major myocutaneous flap for reconstruction is a feasible approach for the treatment of giant cervical metastatic cancers that have developed from unknown primary tumors and have invaded the skin. Post-operative concurrent chemoradiotherapy should be administered to improve the local control rate and

  2. 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

  3. Rotation flaps for coverage after total knee arthroplasty

    PubMed Central

    Pozzobon, Leonardo Rafael; Helito, Camilo Partezani; Guimarães, Tales Mollica; Gobbi, Riccardo Gomes; Pécora, José Ricardo; Camanho, Gilberto Luis

    2013-01-01

    OBJECTIVE: To evaluate the results obtained using local myocutaneous rotation flaps in cases of wound dehiscence after total knee arthroplasty. METHODS: Patients undergoing these surgical procedures were selected in the 2000-2012 period. The nine selected cases during this period were subjected to flap coverage due to skin dehiscence associated with infection. In eight cases we used rotation flaps of the medial gastrocnemius, and in one case we used advancing skin. RESULTS: Eighty nine percent of the cases were successful in the coverage of the prosthesis and the viability of the flaps. In four cases it was possible to maintain or review the prosthesis. Four other cases progressed to amputation due to failure on treatment of infections, and one case remained without the prosthesis. The functional evaluation showed an unsatisfactory outcome in 89% of cases. CONCLUSION: Coverage flaps are a good option for the treatment of cases of dehiscence with exposure of the prosthesis and the functional failure was associated with the inability to control the infection and the damage it caused. Level of Evidence IV, Case Series. PMID:24453672

  4. Extensive full-thickness eyelid reconstruction with rotation flaps through “subcutaneous tunnel” and palatal mucosal grafts

    PubMed Central

    Cheng, Jian-Xia; Zuo, Lan; Huang, Xin-Yu; Cui, Ji-Zhe; Wu, Shuai; Du, Yuan-Yuan

    2015-01-01

    AIM To reconstruct the extensive full-thickness defects of eyelids is a challenge for the plastic surgeon because of their complex anatomy and special functions. This article presents and discusses an improved surgical technique in which the orbicularis oculi myocutaneous flap is rotated through a “subcutaneous tunnel” in conjunction with a palatal mucosal graft employed for lining. METHODS Data from 22 eyes with extensive full-thickness eyelid defects from various causes between 2009 and 2013 were analyzed in this study. After the different layers of eyelid were separated completely, a temporally based orbicularis oculi myocutaneous flap was designed following fishtail lines and was mobilized, leaving the base of the pedicle intact with a submuscular tissue attachment. The flap was then rotated through a “subcutaneous tunnel” to the defect, and the donor site was closed primarily. Posterior lamellar reconstruction was performed with a mucosal graft harvested from the hard palate. RESULTS All the flaps were survived without any healing problems. There was no corneal irritation, flap contraction, or significant donor-site morbidity in the follow-up period. The incision scars were almost invisible. The defects were repaired completely, and the evaluations showed satisfactory function and appearance. CONCLUSION This technique is an improved single-stage operation and can be applied to repair large, full-thickness eyelid defects from various causes. With our method, the functional and aesthetic results can be obtained in either the upper or lower eyelids. PMID:26308255

  5. Satisfaction following Unilateral Breast Reconstruction: A Comparison of Pedicled TRAM and Free Abdominal Flaps

    PubMed Central

    Schwitzer, Jonathan A.; Miller, H. Catherine; Pusic, Andrea L.; Matros, Evan; Mehrara, Babak J.; McCarthy, Colleen M.; Lennox, Peter A.; Van Laeken, Nancy

    2015-01-01

    Background: The purpose of this study was to compare patient satisfaction following unilateral pedicled transverse rectus abdominis myocutaneous (TRAM) and free abdominal flap reconstruction. Methods: Patients who underwent unilateral breast reconstruction using pedicled TRAM or free abdominal flaps (muscle-sparing TRAM or deep inferior epigastric perforator flap) and completed the BREAST-Q were identified from 2 prospectively maintained databases. BREAST-Q scores were assessed and compared for Satisfaction with Breasts, Outcome, and Physical Well-being Chest/Abdomen. Results: Of the 138 patients who completed the BREAST-Q, 84 underwent pedicled TRAM flap reconstruction and 54 underwent free abdominal flap reconstruction. Overall, pedicled TRAM flap patients scored higher than free abdominal flap patients on all 4 BREAST-Q scales. This difference reached statistical significance in Satisfaction with Breasts (+7.74; P = 0.02). Similar results were found among patients who completed the BREAST-Q at <3 years postoperation. However, among patients at ≥3 years postoperation, there were no statistically significant differences between the 2 groups, with the pedicled flap cohort scoring higher in Satisfaction with Breasts and Physical Well-being Chest and the free abdominal flap cohort scoring higher in Satisfaction with Outcome and Physical Well-being Abdomen scores. Conclusions: Patients who underwent unilateral pedicled TRAM flap reconstruction experienced greater initial breast satisfaction than patients who underwent unilateral free abdominal flap reconstruction, but satisfaction equalized between the two over time, suggesting that long-term satisfaction may be equivalent between the 2 methods of reconstruction. PMID:26495195

  6. 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

  7. Segmented vortex flaps

    NASA Technical Reports Server (NTRS)

    Rao, D. M.

    1983-01-01

    Segmented vortex flaps were suggested as a means of delaying the vortex spill-over causing thrust loss over the outboard region of single-panel flaps. Also proposed was hinge-line setback for exploiting leading-edge suction in conjunction with vortex flaps to improve the overall thrust per unit flap area. These two concepts in combination were tested on a 60-deg cropped delta wing model. Significant improvement in flap efficiency was indicated by a reduction of the flap/wing area from 11.4% of single-panel flap to 6.3% of a two segment delta flap design, with no lift/drag penalty at lift coefficients between 0.5 and 0.7. The more efficient vortex flap arrangement of this study should benefit the performance attainable with flaps of given area on wings of moderate leading-edge sweep.

  8. 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

  9. Slotted variable camber flap

    NASA Technical Reports Server (NTRS)

    Andrews, D. G. (Inventor)

    1984-01-01

    Variable camber actuator assemblies broaden the range of speeds at which lift to drag performance is maximized for slotted flap wings. Lift is improved over a broader range of cruising speeds by varying wing camber with rotational flap movements that do not introduce wing slots and induced drag. Forward flaps are secured to forward flange links which extended from, and are a part of forward flap linkage assemblies. The forward flaps rotate about flap pivots with their rotational displacement controlled by variable camber actuator assemblies located between the forward flaps and the forward flange links. Rear flaps are held relative to the forward flaps by rear flap linkage assemblies which may act independently from the forward flap linkage assemblies and the variable camber actuator assemblies. Wing camber is varied by rotating the flaps with the variable camber actuator assemblies while the flaps are in a deployed or tucked position. Rotating the flaps in a tucked position does not introduce significant wing surface discontinuities, and reduces aircraft fuel consumption on most flight profiles.

  10. Reconstruction of knee joint soft tissue and patellar tendon defects using a composite anterolateral thigh flap with vascularized fascia lata.

    PubMed

    Kuo, Yur-Ren; An, Po-Chung; Kuo, Mei-Hui; Kueh, Nai-Siong; Yao, Sheng-Fa; Jeng, Seng-Feng

    2008-01-01

    Reconstruction of a complex knee trauma with knee joint exposure and composite soft tissue and patellar tendon deficiency remains a challenging task. Multiple-stage reconstruction is time-consuming and produces considerable suffering for patients. Early mobilization following knee reconstruction has achieved good outcomes. Herein, we reported one-stage reconstruction with an ALT myocutaneous flap with vascularized fascia lata was utilized for one patient with a large complex knee joint soft tissue defect, and segmental deficiency of the patellar tendon. The fascia lata sheet was rolled to mimic a patellar tendon. The exposed knee joint was obturated by the vastus lateralis muscle of the ALT myocutaneous flap. The skin and soft tissue defect was reconstructed using the skin paddle of the ALT flap. The patient's postoperative course was uneventful. An MRI examination demonstrated good continuity of the reconstructed patellar tendon. The active ROM of the injured knee reached 100 degrees (extension deficiency 20 degrees and flexion 120 degrees ) at 5 years. Objective functional assessment of the patella-femoral joint utilized a kinetic communicator machine (Kin-Com 500H, Chattecx, Chattanooga, TN, USA) revealed still mild extension insufficiency. However, the patient reported that he was able to perform normal daily activities without difficulty at 5-year follow-up. PMID:18215803

  11. 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

  12. Reconstruction of severely infected gluteal osteoradionecrosis using negative-pressure wound therapy and latissimus dorsi musculocutaneous flaps.

    PubMed

    Kim, Sang Wha; Youn, Dong Geun; Hwang, Kyu Tae; Kim, Jeong Tae; Kim, Youn Hwan

    2016-01-01

    Radiotherapy is mandatory for aggressive cancer treatment. Unfortunately, the high-energy radiation used can lead to severe osteoradionecrosis. Radical debridement of devitalized bone and soft tissue coupled with reconstruction using well-vascularized tissues is the accepted treatment for this condition. However, osteoradionecrosis cannot be controlled easily or rapidly. The aim of this study was to present the results of the use of serial negative-pressure wound therapy (NPWT) in combination with a latissimus dorsi myocutaneous flap for treatment of gluteal osteoradionecrosis in a consecutive series of patients. Between January 2003 and December 2012, nine patients underwent reconstruction using serial NPWT and latissimus dorsi myocutaneous flaps. We applied negative-pressure dressings for at least 8 weeks. Final reconstruction was performed after the infection was controlled. The superior gluteal artery and vein were used as recipient vessels in all the cases. The mean interval between operation and radiation therapy was 28.3 ± 8.3 years, and the mean number of debridement performed was 6.3 ± 1. NPWT dressings were applied for 8-12 weeks (mean, 9.3 ± 2 weeks). The defects ranged in size from 14 × 8 cm to 18 × 15 cm. The flap size ranged from 15 × 10 cm to 18 × 15 cm. All flaps survived uneventfully except in one patient who experienced chronic seroma and wound dehiscence. There were no recurrences of osteomyelitis during the follow-up periods (mean, 14 ± 6.1 months). Based on the results obtained from this consecutive series of patients, we suggest that this methodology may provide an alternative approach for the treatment of severe osteoradionecrosis of the gluteal region. PMID:25641653

  13. Reconstruction of a Severely Crushed Leg with Interpositional Vessel Grafts and Latissimus Dorsi Flap

    PubMed Central

    Park, Chan Woo; Hwang, Kyu Tae; Kim, Jeong Tae

    2012-01-01

    We present a case of a near total amputation at the distal tibial level, in which the patient emphatically wanted to save the leg. The anterior and posterior tibial nerves were intact, indicating a high possibility of sensory recovery after revascularization. The patient had open fractures at the tibia and fibula, but no bone shortening was performed. The posterior tibial vessels were reconstructed with an interposition saphenous vein graft from the contralateral side and a usable anterior tibial artery graft from the undamaged ipsilateral distal portions. The skin and soft tissue defects were covered using a subatmospheric pressure system for demarcating the wound, and a latissimus dorsi myocutaneous free flap for definite coverage of the wound. At 6 months after surgery, the patient was ambulatory without requiring additional procedures. Replantation without bone shortening, with use of vessel grafts and temporary coverage of the wound with subatmospheric pressure dressings before definite coverage, can shorten recovery time. PMID:22872848

  14. The ability of intra-operative perfusion mapping with laser-assisted indocyanine green angiography to predict mastectomy flap necrosis in breast reconstruction: a prospective trial.

    PubMed

    Munabi, Naikhoba C O; Olorunnipa, Olushola B; Goltsman, David; Rohde, Christine H; Ascherman, Jeffrey A

    2014-04-01

    Mastectomy skin flap ischaemia leading to necrosis is a common occurrence. Laser-assisted indocyanine green (ICG) angiography can assist to locate these poorly perfused areas intra-operatively. Our study aims to identify specific perfusion values produced by ICG angiography that accurately predict mastectomy flap necrosis. A total of 42 patients undergoing autologous or implant-based breast reconstruction had mastectomy flaps imaged using laser-assisted ICG angiography at the completion of reconstruction. Intra-operative perfusion values were correlated with postoperative skin flap outcomes. Risk factors for abnormal perfusion were recorded and analysed. A total of 62 breast reconstructions were imaged, including 48 tissue expander reconstructions, six transverse rectus abdominis myocutaneous (TRAM) flaps, six deep inferior epigastric perforator (DIEP) flaps and two direct-to-implant reconstructions. Eight cases (13%) of full-thickness skin necrosis were identified postoperatively. A SPY Elite(®) value of ≤ 7 accurately predicted the development of flap necrosis at 88% sensitivity and 83% specificity. False-positive cases (those with perfusion values ≤ 7 which did not develop necrosis) were more likely to have a smoking history and/or to have had an epinephrine-containing tumescent solution used during mastectomy. Excluding patients with smoking or epinephrine use, a SPY value of ≤ 7 predicted flap necrosis with a sensitivity of 83% and specificity of 97%. Thus, these data suggest that laser-assisted ICG angiography predicts postoperative outcomes with high accuracy. In our series, a SPY value of ≤ 7 correlated well with mastectomy flap necrosis. Furthermore, smoking and intra-operative injections containing epinephrine should be considered when evaluating low perfusion values as they can lead to false-positive test results. PMID:24507962

  15. 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.

  16. Oral reconstruction with submental flap

    PubMed Central

    Rahpeyma, Amin; Khajehahmadi, Saeedeh

    2013-01-01

    Background: Submental flap is a useful technique for reconstruction of medium to large oral cavity defects. Hair bearing nature of this flap in men makes it less appropriate. Therefore, deepithelialized variant is introduced to overcome the problem of hair with this flap. Recently, application of this flap has been introduced in maxillofacial trauma patients. Materials and Methods: Deepithelialized orthograde submental flap is used for the reconstruction of oral cavity mucosal defects. Results: Four cases including two trauma patients and two squamous cell carcinomas (SCCs) of oral cavity were treated using deepithelialized orthograde submental flap. There were no complications in all four patients and secondary epithelialization occurred in raw surface of the flap which was exposed to oral cavity. Conclusion: Deepithelialized orthograde submental flap is very effective in reconstruction of oral cavity in men. The problem of hair is readily solved using this technique without jeopardizing flap blood supply. PMID:24205473

  17. 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.

  18. 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.

  19. The microvascular anastomotic coupler for venous anastomoses in free flap breast reconstruction improves outcomes

    PubMed Central

    Rozen, Warren Matthew; Chowdhry, Muhammad; Patel, Nakul Gamanlal; Chow, Whitney T.H.; Griffiths, Matthew; Ramakrishnan, Venkat V.

    2016-01-01

    Background Venous couplers are ubiquitous around the world and are a useful tool for the reconstructive microsurgeon. A systematic review of coupler performance studies demonstrated a thrombosis rate range of 0% to 3%, whilst the average time of using the device is 5 minutes. There is sparse published data on cost analysis and the impact of operator experience on the anastomotic coupler device success. Improvements in outcomes other than time benefits have also not been shown. This study aims to address these deficiencies in the literature. Methods A retrospective clinical study was undertaken, aiming to compare equivalent groups of patients that had free flap surgery with venous micro-anastomoses with those that had sutured anastomoses. The cohort comprised all patients undergoing microsurgical breast reconstruction at the St Andrew’s Centre for Plastic Surgery & Burns from January 2009 to December 2014. Results Between January 2010 to December 2014, 1,064 patients underwent 1,206 free flap breast reconstructions. The average age of patients was 50 years. Seventy percent of patients underwent mastectomy and immediate reconstruction during this period with the remaining 30% having a delayed reconstruction. The 1,206 free flaps comprised of 83 transverse myocutaneous gracilis (TMG) flaps, and 1,123 deep inferior epigastric artery perforator (DIEP) flaps. In total the coupler was used in 319 flaps, 26% of the cohort. There was a statistically significant clinical benefit in using the anastomotic coupler for venous anastomosis. Overall, the return to theatre rate was 12.69% whilst the overall flap loss rate was 0.75%. The overall coupler failure rate was significantly less at 1.4% whilst sutured vein failure rate was 3.57% (P=0.001). Conclusions The anastomotic coupler for venous anastomosis in free flap surgery is associated with reduced operating times, reduced take-backs to theatre and cost benefits. This is the first study to demonstrate clear clinical benefits

  20. Externally blown flap impingement noise

    NASA Technical Reports Server (NTRS)

    Lasagna, P. L.; Putnam, T. W.

    1972-01-01

    Tests of the noise produced by the impingement of the jet exhaust on the wing and flap for an externally blown flap system were conducted with a CF700 turbofan engine and an F-111B wing panel. The noise produced with a daisy nozzle installed on the engine was greater than that produced by a conical nozzle at the same thrust. The presence of the wing next to the test nozzles increased the noise, as did increasing the flap deflection angle. Compared with the conical nozzle, the daisy nozzle produced slightly less noise at a flap deflection of 60 deg but produced more noise at the lower flap deflections tested. Tests showed that the single-slotted flap deflected 60 deg, produced less noise than the double-slotted flaps. Also, maintaining the maximum distance between the exit nozzle and flap system resulted in a minor reduction in noise.

  1. Recent advances for FLAP inhibitors.

    PubMed

    Pettersen, Daniel; Davidsson, Öjvind; Whatling, Carl

    2015-07-01

    A number of FLAP inhibitors have been progressed to clinical trials for respiratory and other inflammatory indications but so far no drug has reached the market. With this Digest we assess the opportunity to develop FLAP inhibitors for indications beyond respiratory disease, and in particular for atherosclerotic cardiovascular disease. We also show how recently disclosed FLAP inhibitors have structurally evolved from the first generation FLAP inhibitors paving the way for new compound classes. PMID:26004579

  2. 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.

  3. 7-flap perineal urethrostomy

    PubMed Central

    Parker, Daniel C.; Morey, Allen F.

    2015-01-01

    Perineal urethrostomy (PU) has been performed with success for the treatment of refractory and advanced urethral stricture disease for at least the past six decades. Here, we review the indications and outcomes of PU for indications such as complex hypospadias repair and urethral stricture disease resulting from trauma, infection, and failure of prior urethroplasty. We also describe the role of 7-flap PU, a novel alternative to the conventional approach that offers the surgeon added flexibility in tailoring urethrostomy creation based on intraoperative findings. The authors’ updated experience with 7-flap PU demonstrates a comparable 95% success rate in patients with a wide variety of stricture etiology. PU through either a conventional approach or a 7-flap technique is a valuable option for improving the quality of life in patients with debilitating urethral stricture disease. PMID:26816809

  4. Externally blown flap impingement noise.

    NASA Technical Reports Server (NTRS)

    Putnam, T. W.; Lasagna, P. L.

    1972-01-01

    An investigation of externally blown flap impingement noise was conducted using a full-scale turbofan engine and aircraft wing. The noise produced with a daisy nozzle installed on the engine exhaust system was greater than that produced by a conical nozzle at the same thrust. The daisy nozzle caused the jet velocity to decay about 35 percent at the flap. The presence of the wing next to the conical nozzle increased the noise, as did increasing the flap deflection. Compared with the conical nozzle, the daisy nozzle produced slightly less noise at a flap deflection of 60 deg but produced more noise at the lower flap deflections tested.

  5. 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.

  6. 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

  7. Uncommon Flaps for Chest Wall Reconstruction

    PubMed Central

    Matros, Evan; Disa, Joseph J.

    2011-01-01

    The omentum, external oblique musculocutaneous, and thoracoepigastric flaps are uncommonly used for chest wall reconstruction. Nevertheless, awareness and knowledge of these flaps is essential for reconstructive surgeons because they fill specific niche indications or serve as lifeboats when workhorse flaps are unavailable. The current report describes the anatomic basis, technical aspects of flap elevation, and indications for these unusual flaps. PMID:22294943

  8. Towards an advanced vortex flap system: The cavity flap

    NASA Technical Reports Server (NTRS)

    Rao, D. M.

    1986-01-01

    An extension of the vortex flap concept was explored with the aim of providing high-alpha flight control capability coupled with maneuver drag reduction for highly swept wing configurations. A retractable lower surface flap mounted on a translating hinge is proposed, allowing chordwise extension as well as deflection, the two movements being independently controlled. The frontal cavity formed by the partially extended and deflected flap captures a vortex above a certain angle of attack. The cavity vortex downwash alleviates the effective incidence of the wing leading edge, thus modulating vortex lift; at the same time, the induced suction in the cavity generates thrust. These postulated aerodynamic features of the cavity flap were validated through low speed tunnel pressure and visualization tests on a 65 deg swept oblique wing model, which also provided initial trends of the leading edge vortex alleviation and cavity suction with respect to flap extension, deflection and angle of attack. Force tests on a 60 deg delta model further showed the cavity flap L/D performance to compare favorably with the conventional vortex flap. A two segment flap arrangement with independently control led segments was envisaged for exploiting the vortex modulation capability of the cavity flap for pitch, roll and yaw control, in addition to drag reduction at high angles of attack.

  9. Superficial ulnar artery perforator flap.

    PubMed

    Schonauer, Fabrizio; Marlino, Sergio; Turrà, Francesco; Graziano, Pasquale; Dell'Aversana Orabona, Giovanni

    2014-09-01

    Superficial ulnar artery is a rare finding but shows significant surgical implications. Its thinness and pliability make this flap an excellent solution for soft tissue reconstruction, especially in the head and neck region. We hereby report a successful free superficial ulnar artery perforator forearm flap transfer for tongue reconstruction. A 64-year-old man presenting with a squamous cell carcinoma of the left tongue underwent a wide resection of the tumor, left radical neck dissection, and reconstruction of the tongue and the left tonsillar pillar with the mentioned flap. No complications were observed postoperatively. The flap survived completely; no recurrence at 6 months of follow-up was detected. Superficial ulnar artery perforator flap has shown to be a safe alternative to other free tissue flaps in specific forearm anatomic conditions. PMID:25102397

  10. Skin flaps and grafts - self-care

    MedlinePlus

    ... Regional flaps - self-care; Distant flaps - self-care; Free flap - self-care; Skin autografting - self-care ... the dressing and area around it clean and free from dirt or sweat. Don't let the ...

  11. Externally blown flap noise research

    NASA Technical Reports Server (NTRS)

    Dorsch, R. G.

    1974-01-01

    The Lewis Research Center cold-flow model externally blown flap (EBF) noise research test program is summarized. Both engine under-the-wing and over-the-wing EBF wing section configurations were studied. Ten large scale and nineteen small scale EBF models were tested. A limited number of forward airspeed effect and flap noise suppression tests were also run. The key results and conclusions drawn from the flap noise tests are summarized and discussed.

  12. The vortex flap

    NASA Astrophysics Data System (ADS)

    Buerge, Brandon T.

    The Vortex Flap is a new type of mechanically driven high-lift device consisting of a rotating cylinder placed underneath and near the trailing edge of an airfoil. Wind tunnel tests were designed and conducted in the Washington University Low-Speed Wind Tunnel. Wind tunnel tests indicate that the Vortex Flap produces notable lift coefficient increments and increases maximum lift coefficients, particularly for the low Reynolds number range tested. The best configurations of the configurations investigated (not necessarily optimal) produce lift increments of 300-900% at low-to-moderate angles of attack, and increase the maximum lift coefficient on the order of 200%. The large lift increments found, particularly at low angles of attack, underscore the ability to drive the airfoil to high lift coefficients even at low angles of attack, a potentially useful characteristic for certain flight maneuvers. Regions of fairly high L/D (on the order of 10) as well as low L/D performance were identified. The nondimensional cylinder rotation speed was found to be the most important experimental parameter. Methods for correcting wind tunnel data were developed and outlined, and a Response Surface Method was applied to the corrected data for ease of interpretation. Performance comparisons between the Vortex Flap and other trailing-edge high-lift devices are included. To demonstrate the potential of the device, a Navy mission specification for a VTOL ship-borne UAV, currently filled by a rotary-wing aircraft, is analyzed using a hypothetical fixed wing aircraft and the Vortex Flap. It is demonstrated that, under certain reasonable wind-over-deck conditions, such an aircraft could hypothetically fill a VTOL mission.

  13. 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

  14. 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.

  15. 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.

  16. Deep circumflex iliac perforator flap.

    PubMed

    Kimata, Yoshihiro

    2003-07-01

    The increased freedom of the DCIP flap from the harvested iliac crest facilitates correct positioning. To ensure that the DCIP flap can be safely elevated, however, the presence of perforators (approximately 1 cm in diameter) must be confirmed preoperatively and intraoperatively. PMID:12916597

  17. Theory of flapping flight

    NASA Technical Reports Server (NTRS)

    Lippisch, Alexander

    1925-01-01

    Before attempting to construct a human-powered aircraft, the aviator will first try to post himself theoretically on the possible method of operating the flapping wings. This report will present a graphic and mathematical method, which renders it possible to determine the power required, so far as it can be done on the basis of the wing dimensions. We will first consider the form of the flight path through the air. The simplest form is probably the curve of ordinary wave motion. After finding the flight curve, we must next determine the change in the angle of attack while passing through the different phases of the wave.

  18. 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.

  19. Dancing girl flap: a new flap suitable for web release.

    PubMed

    Shinya, K

    1999-12-01

    To create a deep web, a flap must be designed to have a high elongation effect in one direction along the mid-lateral line of the finger and also to have a shortening effect in the other direction, crossing at a right angle to the mid-lateral line. The dancing girl flap is a modification of a four-flap Z-plasty with two additional Z-plasties. It has a high elongation effect in one direction (>550%) and a shortening effect in the other direction at a right angle (<33%), creating a deep, U-shaped surface. This new flap can be used to release severe scar contracture with a web, and is most suitable for incomplete syndactyly with webs as high as the proximal interphalangeal joint. PMID:10597822

  20. Keystone Flap: Versatile Flap for Reconstruction of Limb Defects

    PubMed Central

    Janna, Rakesh K.

    2015-01-01

    Background: There is always a constant search for a new solution to tackle defects in the limbs. The technique has to be simple, easily reproducible and performed within a short duration. The answer is keystone island flap keystone flap is a simple, less time consuming, durable and easily reproducible option to reconstruct most of the limb defects. Aim: The aim of this article is to study the usefulness of keystone flap in reconstruction of various upper and lower limb defects. Materials and Methods: This retrospective review involves study of 20 patients undergoing keystone flap reconstruction for various defects from 2012 to 2014. Patient demographic data, medical histories, comorbidities, surgical indications, defect characteristics and locations, hospitalization, complications and follow-up were evaluated and are presented as uncontrolled case series. Results: Ages of the patients were ranging from 18 to 65 y with an average of 38.75y. Among the defects, 10 were following trauma (50%), 5 were due to tumour resection (25%), 3 followed debridement of abscess (15%) and another 2 defects were due to surgical wound dehiscence (10%). The largest defect covered by this flap in our study measured 45 x 18 cm and the smallest defect was 8 x4 cm. The average intra-operative time was 45.5 min (range 20-90 min). Fourteen flaps were done to cover lower limb defects (70%), 4 for upper limb defects and 2 were for defects in the axilla. Partial flap necrosis was observed in one case. The average duration of hospital stay of patients was 3.45 d. All patients were followed until they achieved stable, healed wound.The overall success rate was 95%. Conclusion: Keystone flap can be safely used to cover various limb defects with minimal pain, a sensate cover and excellent cosmetic outcome, minimizing the need for microsurgical techniques or prolonged operative time. PMID:25954659

  1. 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.

  2. 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.

  3. Perforator Flaps in Head and Neck Reconstruction

    PubMed Central

    Chana, Jagdeep S.; Odili, Joy

    2010-01-01

    Free tissue transfer has revolutionized the management of complex head and neck defects. Perforator flaps represent the most recent advance in the development of free flap surgery. These flaps are based on perforating vessels and can be harvested without significant damage to associated muscles, thereby reducing the postoperative morbidity associated with muscle-based flaps. Elevation of perforator flaps requires meticulous technique and can be more challenging than raising muscle-based flaps. Use of a Doppler device enables reliable identification of the perforating vessels and aids in the design of free-style free flaps, where the flaps are designed purely according to the perforator located. The major advantage of free-style free flaps is that an unlimited number of flaps can potentially be designed on much shorter pedicles. The anterolateral thigh flap is the most commonly used perforator flap in head and neck reconstruction. Its use is described in detail, as is use of other less common perforator flaps. This article also describes head and neck reconstruction in a region-specific manner and gives a short-list of suitable flaps based on the location of the defect. PMID:22550446

  4. Modified osteomyocutaneous iliac crest flaps transplantation.

    PubMed

    Liu, Jun; Song, Dajiang; Li, Jinsong; Xu, Jian; Lv, Hongbin

    2015-04-01

    The paper aims to improve the operative technique of osteomyocutaneous iliac crest flap harvesting, further minimise morbidity of donor site, and improve the effect of recipient site reconstruction. From March 2005 to March 2011, 55 cases of osteomyocutaneous iliac crest flap harvested by different methods were performed to reconstruct the defects of the extremities. Twenty-nine cases were reconstructed with a traditional deep circumflex iliac artery osteomusculocutaneous flap. Twenty-six cases were repaired with modified osteomyocutaneous iliac crest flaps. In 29 cases with a traditional DCIA osteomusculocutaneous flap, two cases showed the injured lateral femoral cutaneous nerve. Flapnecrosis was significant in two cases. Arterial compromise occurred in one case 5 days after operation completion and led to flap failure. Three flaps developed postoperative venous congestion, but only one flap received re-exploration. In the other two cases, some stitches were removed for decompression. All three flaps survived. In two cases, marginal flap necrosis occurred, but no secondary skin grafting was required. In 26 cases with modified flap transplantation, one case showed the injured lateral femoral cutaneous nerve. All flaps survived totally. Osseous integration was achieved in all 55 cases in 3 ∼ 9 months after operation. The modified osteomyocutaneous iliac crest flap technique enhances flap safety, provides the additional advantages of reducing donor-site morbidity, and improves the recipient-site contour. PMID:25001367

  5. 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

  6. Experience in Reconstruction for Small Digital Defects With Free Flaps.

    PubMed

    Hung, Min-Hsiang; Huang, Kuo-Feng; Chiu, Haw-Yen; Chao, Wai-Nang

    2016-03-01

    Traumatic injuries to the digits resulting in soft tissue or bone loss require reconstruction. Traditionally, local flaps, such as homodigital flaps, heterodigital flaps, pedicled flaps, or distant flaps, are used for digital resurfacing. However, free tissue transfers can be used in selected patients. In this study, we present the use of different free flaps including groin skin flaps, groin osteocutaneous flaps, groin chimeric flaps, second dorsal metacarpal artery flaps, and partial toe flaps for digital reconstruction. A total of 19 digits were treated with 16 free flaps in our hospital. Of the flaps used, 5 were free groin skin flaps, 4 were free partial toe flaps, 3 were free groin chimeric flaps, 2 were free groin osteocutaneous flaps, and 2 were free second dorsal metacarpal artery flaps. The average flap size was 4.7 × 2.0 cm (range, 1.5 × 1 to 5 × 4 cm), and the average operative time was 6.0 hours (range, 4-9 hours). All flaps survived without partial or total necrosis. In conclusion, the free flap is a reliable and safe alternative for digital reconstruction. Moreover, the free groin flap provides not only a chimeric pattern for multiple fingers coverage but also an osteocutaneous pattern for thumb lengthening. The free second dorsal metacarpal artery flap provides a tenocutaneous pattern for tendon reconstruction and soft tissue coverage simultaneously, and the free partial toe flap is an excellent alternative for pulp reconstruction in terms of aesthetic appearance and functional outcome. PMID:26808771

  7. 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

  8. Treatment of degloving injury involving multiple fingers with combined abdominal superficial fascial flap, dorsalis pedis flap, dorsal toe flap, and toe-web flap

    PubMed Central

    Han, Fengshan; Wang, Guangnan; Li, Gaoshan; Ping, Juan; Mao, Zhi

    2015-01-01

    Background Our aim was to summarize the treatment of degloving injury involving multiple fingers using combined abdominal superficial fascial flap, dorsalis pedis flap, dorsal toe flap, and toe-web flap. Patients and methods Each degloved finger was debrided under microscopic guidance and embedded in the superficial layer of the abdominal fascia. The abdominal skin was sutured to the skin on the back and side of the hand to promote circumferential healing. After removal, the only remaining injured region was on the flexor surface, and this was repaired by multiple dorsal toe flaps, toe-web flaps, and dorsalis pedis flaps to provide blood vessels and sensory nerves. All fingers had proper flap thickness 3–6 months after surgery, and required only lateral Z-plasty modification with web deepening and widening to narrow the fingers and extend their relative length. Results We completed flap-graft and finger narrowing for 25 fingers in eight patients. Abdominal skin flaps and dorsal toe flaps were grafted, and resulted in both firmness and softness, providing finger flexibility. The dorsal toe flap provided good blood circulation and sensory nerves, and was used to cover the finger-flexor surface to regain sensation and stability when holding objects. During the 1–8 years of follow-up, sensation on the finger-flexor side recovered to the S3–4 level, and patient satisfaction based on the Michigan Hand Outcomes Questionnaire was 4–5. Flap ulcers or bone/tendon necrosis were not observed. Conclusion Treatment of degloving injury involving multiple fingers with combined abdominal superficial fascial flap, dorsalis pedis flap, dorsal toe flap, and toe-web flap was effective and reliable. PMID:26229479

  9. 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.

  10. 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.

  11. Free thin paraumbilical perforator-based flaps.

    PubMed

    Koshima, I; Moriguchi, T; Soeda, S; Tanaka, H; Umeda, N

    1992-07-01

    A free paraumbilical perforator-based flap fed by a muscle perforator from the inferior deep epigastric artery and with no muscle was used in 13 patients. Among them, a free thin paraumbilical perforator-based flap with a thin layer of fat, to protect the subdermal plexus of the vessels, was used in seven patients. The dominant pedicle perforator of this thin flap is usually located around the umbilicus and a large flap can be obtained. Its critical length-to-breath ratio is considered to be 4:3. The advantages of this flap are a long and large vascular pedicle, rare postoperative abdominal herniation, little bulkiness of the flap, and a relatively large skin territory. The disadvantages are technical difficulties in dissection of the perforator and anatomical variation in the location of the perforator. We believe this flap largely overcomes the problems of the conventional rectus abdominis musculocutaneous flap. PMID:1386718

  12. 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. PMID:25841702

  13. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flap interconnection. 23.701 Section 23.701... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.701 Flap interconnection. (a) The main wing flaps and related movable surfaces as a...

  14. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flap interconnection. 23.701 Section 23.701... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.701 Flap interconnection. (a) The main wing flaps and related movable surfaces as a...

  15. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flap interconnection. 23.701 Section 23.701... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.701 Flap interconnection. (a) The main wing flaps and related movable surfaces as a...

  16. The bilobed flap for popliteal defect reconstruction

    PubMed Central

    Kelahmetoglu, Osman; Yagmur, Caglayan; Aslan, Ozan; Firinciogullari, Remzi

    2014-01-01

    Abstract Bilobed flaps were first introduced to close small nasal defects. We reconstructed a defect of the popliteal fossa using a random-pattern bilobed flap. We recommend the use of random-pattern bilobed flaps as a reliable technique for covering defects of the popliteal fossa.

  17. 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

  18. Four-flap Breast Reconstruction: Bilateral Stacked DIEP and PAP Flaps

    PubMed Central

    Mayo, James L.; Allen, Robert J.

    2015-01-01

    Background: In cases of bilateral breast reconstruction when the deep inferior epigastric perforator (DIEP) free flap alone does not provide sufficient volume for body-specific reconstruction, stacking each DIEP flap with a second free flap will deliver added volume and maintain a purely autologous reconstruction. Stacking the profunda artery perforator (PAP) flap with the DIEP flap offers favorable aesthetics and ideal operative efficiency. We present the indications, technique, and outcomes of our experience with 4-flap breast reconstruction using stacked DIEP/PAP flaps. Methods: The authors performed 4-flap DIEP/PAP breast reconstruction in 20 patients who required bilateral reconstruction without adequate single donor flap volume. The timing of reconstruction, average mastectomy/flap weights, and operative time are reported. Complications reviewed include fat necrosis, dehiscence, hematoma, seroma, mastectomy flap necrosis, and flap loss. Results: Twenty patients underwent 4-flap DIEP/PAP breast reconstruction. Surgical time averaged 7 hours and 20 minutes. The primary recipient vessels were the antegrade and retrograde internal mammary vessels. No flap losses occurred. Complications included 1 hematoma, 1 incidence of arterial and venous thrombosis successfully treated with anastomotic revision, 1 incidence of thigh donor site dehiscence, and 3 episodes of minor mastectomy skin flap necrosis. Conclusions: Four-flap breast reconstruction is a favorable autologous reconstructive option for patients requiring bilateral reconstruction without adequate single donor flap volume. Stacking DIEP/PAP flaps as described is both safe and efficient. Furthermore, this combination provides superior aesthetics mirroring the natural geometry of the breast. Bilateral stacked DIEP/PAP flaps represent our first choice for breast reconstruction in this patient population. PMID:26090273

  19. Cost-effectiveness of monitoring free flaps.

    PubMed

    Subramaniam, Shiva; Sharp, David; Jardim, Christopher; Batstone, Martin D

    2016-06-01

    Methods of free flap monitoring have become more sophisticated and expensive. This study aims to determine the cost of free flap monitoring and examine its cost effectiveness. We examined a group of patients who had had free flaps to the head and neck over a two-year period, and combined these results with costs obtained from business managers and staff. There were 132 free flaps with a success rate of 99%. The cost of monitoring was Aus $193/flap. Clinical monitoring during this time period cost Aus$25 476 and did not lead to the salvage of any free flaps. Cost equivalence is reached between monitoring and not monitoring only at a failure rate of 15.8%. This is to our knowledge the first study to calculate the cost of clinical monitoring of free flaps, and to examine its cost-effectiveness. PMID:27015730

  20. Scrotal reconstruction with modified pudendal thigh flaps.

    PubMed

    Mopuri, Nabil; O'Connor, Edmund Fitzgerald; Iwuagwu, Fortune C

    2016-02-01

    Scrotal skin loss can occur following trauma, Fournier's gangrene, post tumour excision, burns, etc. There are many techniques described in the literature including residual scrotal skin mobilization, skin grafts, pedicled and free flaps. The management is complex and challenging shown by the multiplicity of flaps and techniques described in the literature. We used a modified pudendal thigh flap to reconstruct scrotal defects in five patients. This study describes the vascularity of the flap, technique of elevation and the inset of the flap. The elevation and particularly the insetting make it different from other flaps raised on this vascular network for scrotal reconstruction. This pedicled flap is robust, reliable, resilient and produces a neo-scrotum that looks natural in appearance, offers good-quality skin cover and cushion to the testes as well as protective sensation. PMID:26774357

  1. Flap--edge flowfield measurements

    NASA Astrophysics Data System (ADS)

    Pye, John D.; Cantwell, Brian J.

    1997-11-01

    Recent studies of airframe noise suggest that the wing and flap trailing--edges as well as the flap side--edge are areas of significant noise generation. To identify the fluid dynamic processes associated with these noise sources, we are examining the flow--field around a NACA 63--215 Mod B main element airfoil configured with a half--span Fowler flap. The tests are performed in a low--speed wind tunnel at a Reynolds number of ~ 6.0×10^5. A hot wire traverse system is used to map the mean velocities and turbulence intensities in the near wake region of the flow. Measurements of the pressure fluctuations along the flap side--edge and in the cove of the airfoil configuration are made with pressure transducers mounted inside the airfoil. The experimental data are in good qualitative agreement with the numerical simulation of a slightly higher Reynolds number flow ( ~ 1.5×10^6) around a geometrically similar airfoil configuration.

  2. 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

  3. Force Generation by Flapping Foils

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, P. R.; Donnelly, M.

    1996-11-01

    Aquatic animals like fish use flapping caudal fins to produce axial and cross-stream forces. During WW2, German scientists had built and tested an underwater vehicle powered by similar flapping foils. We have examined the forces produced by a pair of flapping foils. We have examined the forced produced by a pair of flapping foils attached to the tail end of a small axisymmetric cylinder. The foils operate in-phase (called waving), or in anti-phase (called clapping). In a low-speed water tunnel, we have undertaken time-dependent measurements of axial and cross-stream forces and moments that are exerted by the vortex shedding process over the entire body. Phase-matched LDV measurements of vorticity-velocity vectors, as well as limited flow visualization of the periodic vortex shedding process have also been carried out. The direction of the induced velocity within a pair of shed vortices determines the nature of the forces produced, viz., thrust or drag or cross-stream forces. The clapping mode produces a widely dispersed symmetric array of vortices which results in axial forces only (thrust and rag). On the other hand, the vortex array is staggered in the waving mode and cross-stream (maneuvering) forces are then generated.

  4. 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.

  5. 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.

  6. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  7. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  8. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  9. 14 CFR 23.697 - Wing flap controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Wing flap controls. 23.697 Section 23.697... Systems § 23.697 Wing flap controls. (a) Each wing flap control must be designed so that, when the flap... with § 23.145(b)(3) necessitates wing flap retraction to positions that are not fully retracted,...

  10. 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

  11. Pressure Distribution Over Airfoils with Fowler Flaps

    NASA Technical Reports Server (NTRS)

    Wenzinger, Carl J; Anderson, Walter B

    1938-01-01

    Report presents the results of tests made of a Clark y airfoil with a Clark y Fowler flap and of an NACA 23012 airfoil with NACA Fowler flaps. Some of the tests were made in the 7 by 10-foot wind tunnel and others in the 5-foot vertical wind tunnel. The pressures were measured on the upper and lower surfaces at one chord section both on the main airfoils and on the flaps for several angles of attack with the flaps located at the maximum-lift settings. A test installation was used in which the model was mounted in the wind tunnel between large end planes so that two-dimensional flow was approximated. The data are given in the form of pressure-distribution diagrams and as plots of calculated coefficients for the airfoil-and-flap combinations and for the flaps alone.

  12. 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

  13. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... flaps or slats retracted on one side and extended on the other, the motion of flaps or slats on opposite...) For airplanes with flaps or slats that are not subjected to slipstream conditions, the structure...

  14. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... flaps or slats retracted on one side and extended on the other, the motion of flaps or slats on opposite...) For airplanes with flaps or slats that are not subjected to slipstream conditions, the structure...

  15. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... flaps or slats retracted on one side and extended on the other, the motion of flaps or slats on opposite...) For airplanes with flaps or slats that are not subjected to slipstream conditions, the structure...

  16. Four Flaps Technique for Neoumbilicoplasty

    PubMed Central

    Lee, Young Taek; Kwon, Chan; Rhee, Seung Chul; Cho, Sang Hun

    2015-01-01

    The absence or disfigurement of the umbilicus is both cosmetically and psychologically distressing to patients. The goal of aesthetically pleasing umbilical reconstruction is to create a neoumbilicus with sufficient depth and good morphology, with natural-looking superior hooding and minimal scarring. Although many reports have presented techniques for creating new and attractive umbilici, we developed a technique that we term the "four flaps technique" for creating a neoumbilicus in circumstances such as the congenital absence of the umbilicus or the lack of remaining umbilical tissue following the excision of a hypertrophic or scarred umbilicus. This method uses the neighboring tissue by simply elevating four flaps and can yield sufficient depth and an aesthetically pleasing shape with appropriate superior hooding. PMID:26015893

  17. Axial pattern skin flaps in cats.

    PubMed

    Remedios, A M; Bauer, M S; Bowen, C V; Fowler, J D

    1991-01-01

    The major direct cutaneous vessels identified in the cat include the omocervical, thoracodorsal, deep circumflex iliac, and caudal superficial epigastric arteries. Axial pattern skin flaps based on the thoracodorsal and caudal superficial epigastric arteries have been developed in cats. Rotation of these flaps as islands allows skin coverage to the carpus and metatarsus, respectively. The thoracodorsal and caudal superficial epigastric flaps provide a practical, one-step option in the reconstruction of large skin defects involving the distal extremities of cats. PMID:2011063

  18. Craniotomy flap osteomyelitis: a diagnostic approach

    SciTech Connect

    Blumenkopf, B.; Hartshorne, M.F.; Bauman, J.M.; Cawthon, M.A.; Patton, J.A.; Friedman, A.H.

    1987-01-01

    Nine cases of suspected craniotomy flap osteomyelitis evaluated by combined bone and gallium scanning are presented. In six cases, the clinical data were inconclusive and evaluation by radionuclide imaging provided an accurate negative diagnosis. The other three cases considered positive by this technique were proven infected at subsequent exploration and flap removal. The use of radionuclide bone and gallium imaging should be considered in cases of possible craniotomy flap osteomyelitis.

  19. Wing flapping with minimum energy

    NASA Technical Reports Server (NTRS)

    Jones, R. T.

    1980-01-01

    A technique employed by Prandtl and Munk is adapted for the case of a wing in flapping motion to determine its lift distribution. The problem may be reduced to one of minimizing induced drag for a specified and periodically varying bending moment at the wing root. It is concluded that two wings in close tandem arrangement, moving in opposite phase, would eliminate the induced aerodynamic losses calculated

  20. A water tunnel study of Gurney flaps

    NASA Technical Reports Server (NTRS)

    Neuhart, Dan H.; Pendergraft, Odis C., Jr.

    1988-01-01

    Several Gurney flap configurations were tested in the NASA Langley 16 x 24 inch Water Tunnel. These devices provided an increased region of attached flow on a wing upper surface relative to the wing without the flaps. The recirculation region behind the flap was visualized and shown to be consistent with hypotheses stated in previous research. Although the test Reynolds number for this study was several orders of magnitude below those in previous investigations, the effect of the Gurney flaps is in qualitative agreement with them. This is as would be expected from first order effects for high lift devices.

  1. An investigation of the flap edge flowfield

    NASA Astrophysics Data System (ADS)

    Pye, John David

    To identify and understand the fluid dynamic processes associated with flow in the region of a flap side edge, a NACA 63-215 Mod B main element with a half-span Fowler flap was tested in the JIAA Low Speed Wind Tunnel at Stanford University. Measurements were made using a variety of techniques to capture the effects of the flap edge vortex. Pressure sensitive paint was applied to the upper surface of both the flap and main element, as well as to the flap side edge. Fast response pressure transducers were mounted interior to the model to measure surface pressure fluctuations on the flap side edge. Single component hotwire data was taken in the near wake region of the flap edge. In addition to the data experimentally obtained, a computational data set of a geometrically similar model at a flight Reynolds number was used for comparison. The data indicates the presence of a dual vortex structure along the flap side edge. This structure is seen to grow, merge, and ultimately become a single symmetric vortex as it progresses downstream. Surface pressure fluctuations on the side edge scale as three power laws with free stream velocity as different flow regions are encountered. By varying the model rigging, indications of a confined source region for the pressure fluctuations were observed. A spatial survey of the correlation between flap side edge surface pressure fluctuations and the near-wake fluctuating velocity field shows increased correlation coefficients for the region surrounding the vortex core.

  2. 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

  3. 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.

  4. A new classification of spreader flap techniques.

    PubMed

    Wurm, Jochen; Kovacevic, Milos

    2013-12-01

    The objective of this study was to introduce various spreader flap technique modifications to adjust the width of the middle nasal vault in patients who underwent rhinoplasties with humpectomy. Decisive modifications of current spreader flap techniques were performed to allow a more natural restoration of the middle nasal vault and the internal nasal valve after humpectomy. Additional steps provide tools to adjust the width and shape of the middle nasal vault according to patients' requirements. The techniques were categorized into "basic spreader flaps," "flaring spreader flaps," "support spreader flaps," and "interrupted spreader flaps." The various spreader flap techniques were used during 576 primary septorhinoplasties in patients with hump noses, hump/crooked noses, or hump/tension noses. The average follow-up was 19 months. Patients who received basic spreader flaps or a flaring spreader flaps tended to show a slightly too wide middle nasal vault, revision surgery was necessary in four of these cases. All other patients showed an appropriate width in the middle nasal vault and an aesthetically pleasing course of the dorsal aesthetic lines. No signs of inverted v deformities or collapse of the internal nasal valve were observed in any of the patients. Patients who had reported impaired nasal breathing preoperatively described clearly improved subjective symptoms. The described techniques appear to be appropriate and highly promising as a supplement to existing procedures for reconstructing the middle nasal vault and internal nasal valves. No additional cartilage grafts are needed. PMID:24327250

  5. 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

  6. Arterialized Venous Bone Flaps: An Experimental Investigation.

    PubMed

    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

  7. [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

  8. Secondary onlay free flap reconstruction of glossectomy defects following initial successful flap restoration.

    PubMed

    Rihani, Jordan; Lee, Thomas; Ducic, Yadranko

    2013-08-01

    Patients who undergo tongue reconstruction over time may develop gradual worsening of dysarthria and dysphagia secondary to flap atrophy. At our institution, these patients undergo a secondary flap onlay procedure for augmentation of the neotongue. We review a total of 11 patients with total glossectomy defect who underwent secondary tongue augmentation with secondary onlay free flap consisting of radial forearm free flap (n = 6) and rectus free flap (n = 5). There was improvement in swallowing in 7 of 11 patients. Five (45.4%) patients achieved gastric tube independence. Seven (63.6%) patients achieved a varying degree of oral intake. All patients achieved tracheostomy independence. Dysarthria was improved in all patients. There were no flap failures. Therefore, a secondary onlay flap technique is feasible and may improve dysphagia and dysarthria to achieve gastric tube and tracheostomy independence in total glossectomy patients with delayed tongue atrophy. PMID:23625797

  9. Distally based sural artery flap without sural nerve.

    PubMed

    Motamed, Sadrollah; Yavari, Masood; Mofrad, Hamid Reza Hallaj; Rafiee, Reza; Shahraki, Feaz Niazi

    2010-01-01

    The distal third of the tibia, ankle and heel area is difficult to reconstruct. For small to medium size defects, local flaps are often an easier alternative than free flap. In lower limb surgery, the sural flap is based on this principle and this flap is becoming increasingly popular. The distally based superficial sural artery flap, first described as a distally based neuro skin flap by masquelet et al., is a skin island flap supplied by the vascular axis of the sural nerve. The main disadvantage of distally based sural artery flap is sacrifice of the sural nerve because it is described the concept of neurocutaneus island flap. We describe one case of reverse sural flap without sural nerve .The aim of this paper is to establish the reliability of this flap even without sural nerve. PMID:21133008

  10. Free flap pulse oximetry utilizing reflectance photoplethysmography.

    PubMed

    Zaman, T; Kyriacou, P A; Pal, S K

    2013-01-01

    The successful salvage of a free flap is dependent on the continuous monitoring of perfusion. To date there is no widely accepted and readily available post-operative monitoring technique to reliably assess the viability of free flaps by continuously monitoring free flap blood oxygen saturation. In an attempt to overcome the limitations of the current techniques a reflectance photoplethysmographic (PPG) processing system has been developed with the capability of real-time estimation of arterial oxygen saturation (SpO2) levels implemented in LabVIEW. This system was evaluated in clinical measurements on five patients undergoing breast reconstruction using Deep Inferior Epigastric Perforator (DIEP) flap. Good quality PPG signals were obtained from the flaps and fingers simultaneously. The estimated free flap SpO2 values were in broad agreement with the oxygen saturation readings from the commercial pulse oximeter. The results suggest that reflectance free flap photoplethysmography can be used as a continuous monitoring technique to non-invasively monitor the perfusion of free flaps. PMID:24110620

  11. 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 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.701 Flap...

  12. 14 CFR 23.701 - Flap interconnection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flap interconnection. 23.701 Section 23.701 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.701 Flap...

  13. Use of free flaps in burn trauma.

    PubMed

    Tvrdek, M; Nejedlý, A; Kletenský, J; Pros, Z; Broz, L

    1994-01-01

    The present currently used method of treating and reconstructing injuries caused by electric current and deep thermal injuries is compared with the method of early reconstruction using free flaps. Brief summary of present experience substantiating this method is presented. The three presented clinical cases show subacute reconstruction in this type of injury by free flaps transfer. PMID:7618395

  14. 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....

  15. 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....

  16. 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....

  17. 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....

  18. 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....

  19. The posterior calf fascial free flap.

    PubMed

    Walton, R L; Matory, W E; Petry, J J

    1985-12-01

    Six posterior calf fascial free flaps were employed to reconstruct defects of the upper and lower extremities. One flap failed due to a constricting dressing. Two flaps sustained partial loss secondary to bleeding and hematoma formation. One flap dehisced at the distal suture line due to mobility of an underlying fracture. All surviving flaps eventually healed and resulted in stable, thin coverage. Donor-site morbidity has been minimal. Shortcomings of this flap model have been defined in the peculiarities of its thinness, diffuse vascular oozing, the extent of the vascular territory, and in postoperative monitoring. These problems are analyzed and recommendations for their resolution are presented. Fascia represents a unique tissue which offers an exciting new dimension in the reconstruction of certain defects--particularly those in which thinness is a desirable option. In the posterior calf model, the inclusion of fat represents an alternative modification that allows the surgeon to tailor the design to a variety of problems where fascia alone is too thin and a cutaneous flap is too thick. This concept may find its greatest application in wounds involving the hand or foot. We believe that this and other fascial flap prototypes may offer an ideal solution for reconstruction of major wounds of the extremities. PMID:3906718

  20. Thumb Reconstruction Using Foucher’s Flap

    PubMed Central

    Kola, Nardi

    2016-01-01

    BACKGROUND: Extensive pulp defects of the thumb, with the exposure of tendon or bone, are challenging reconstructive problems. Surgical treatment includes the use of local, regional, and free flaps. AIM: This paper is focused in Foucher’s neuro vascular flap. First DMCA or Foucher’s pedicle flap is a successful thumb reconstruction method, especially in patients not disturbed by its cosmetic appearance. MATERIAL AND METHODS: The first dorsal metacarpal artery (FDMCA) arises from the radial artery in the first intermetacarpal space, just distal to the tendon of the extensor pollicis longus. Pulp area of the thumb is the area where Foucher’s flap is more utilizable. This technique has other applications such as first web reconstruction, thumb lengthening, and following resection of tumors on the dorsum of the hand. RESULTS: We have in study 7 cases with work related trauma in two years period of time, between 2012 and 2014. We had only one partial flap survival and all the other flaps survived entirely. We have also taken in consideration subjective satisfaction with a range score from 4 to 10, cold intolerance, flap area and donor site sensibility with a range score from low to medium to normal. CONCLUSION: Careful pedicle discovery, secured elevation, pedicle strangulation prevention are very important for flap survival.

  1. The clinical application of anterolateral thigh flap.

    PubMed

    Lee, Yao-Chou; Chiu, Haw-Yen; Shieh, Shyh-Jou

    2011-01-01

    The anterolateral thigh flap can provide a large skin paddle nourished by a long and large-caliber pedicle and can be harvested by two-team work. Most importantly, the donor-site morbidity is minimal. However, the anatomic variations decreased its popularity. By adapting free-style flap concepts, such as preoperative mapping of the perforators and being familiar with retrograde perforator dissection, this disadvantage had been overcome gradually. Furthermore, several modifications widen its clinical applications: the fascia lata can be included for sling or tendon reconstruction, the bulkiness could be created by including vastus lateralis muscle or deepithelization of skin flap, the pliability could be increased by suprafascial dissection or primary thinning, the pedicle length could be lengthening by proximally eccentric placement of the perforator, and so forth. Combined with these technical and conceptual advancements, the anterolateral thigh flap has become the workhorse flap for soft-tissue reconstructions from head to toe. PMID:22567234

  2. Fasciocutaneous flap for vaginal and perineal reconstruction

    SciTech Connect

    Wang, T.N.; Whetzel, T.; Mathes, S.J.; Vasconez, L.O.

    1987-07-01

    A skin and fascia flap from the medial thigh is proposed for vaginal and perineal reconstruction. Dissection, vascular injection, and radiographs of 20 fresh cadaver limbs uniformly demonstrated the presence of a communicating suprafascial vascular plexus in the medial thigh. Three to four nonaxial vessels were consistently found to enter the proximal plexus from within 5 cm of the perineum. Preservation of these vessels permitted reliable elevation of a 9 X 20 cm fasciocutaneous flap without using the gracilis muscle as a vascular carrier. Fifteen flaps in 13 patients were used for vaginal replacement and coverage of vulvectomy, groin, and ischial defects. Depending on the magnitude of the defect, simultaneous and independent elevation of the gracilis muscle provided additional vascularized coverage as needed. Our experience indicates that the medial thigh fasciocutaneous flap is a durable, less bulky, and potentially sensate alternative to the gracilis musculocutaneous flap for vaginal and perineal reconstruction.

  3. 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.

  4. 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.

  5. 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. PMID:24037925

  6. Pudendal thigh flap for repair of rectovaginal fistula.

    PubMed

    Sathappan, S; Rica, M A I

    2006-08-01

    The pudendal thigh flap or the Singapore flap is a versatile flap that can be used in the repair of recto-vaginal fistulae. Apart from the potential problem of hair growth, this neurovascular flap proves to be surprisingly simple in technique, robust and has a high potential for normal or near-normal function. PMID:17240589

  7. Hydrodynamic schooling of flapping swimmers.

    PubMed

    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

  8. Hydrodynamic schooling of flapping swimmers

    DOE PAGESBeta

    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

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. New drag laws for flapping flight

    NASA Astrophysics Data System (ADS)

    Agre, Natalie; Zhang, Jun; Ristroph, Leif

    2014-11-01

    Classical aerodynamic theory predicts that a steadily-moving wing experiences fluid forces proportional to the square of its speed. For bird and insect flight, however, there is currently no model for how drag is affected by flapping motions of the wings. By considering simple wings driven to oscillate while progressing through the air, we discover that flapping significantly changes the magnitude of drag and fundamentally alters its scaling with speed. These measurements motivate a new aerodynamic force law that could help to understand the free-flight dynamics, control, and stability of insects and flapping-wing robots.

  16. Blended Cutout Flap for Reduction of Jet-Flap Interaction Noise

    NASA Technical Reports Server (NTRS)

    Czech, Michael J (Inventor); Thomas, Russell H. (Inventor)

    2014-01-01

    An aircraft system includes a wing and a trailing edge device coupled to the wing. The trailing edge device is movable relative to the wing, and includes a leading edge and a trailing edge having a center flap portion and a plurality of outer edge portions integrally combined with the center flap portion such that the center flap portion is shorter in width than that of outer edge portions.

  17. 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. PMID:26405422

  18. Locoregional use of lateral thoracic artery perforator flap as a propeller flap.

    PubMed

    Baghaki, Semih; Cevirme, Mirza; Diyarbakirli, Murat; Tatar, Cihad; Aydin, Yagmur

    2015-05-01

    Although thoracodorsal system is a fundamental source of various flaps, lateral thoracic region has not been a popular flap donor area. There is limited data on the use of lateral intercostal artery perforator flap and lateral thoracic artery perforator flap. In this case series, lateral thoracic artery perforator flap has been used in locoregional (axilla, pectoral region, and arm) reconstruction as an island or propeller flap.Eighteen patients have been operated on between September 2010 and January 2013. The age of the patients ranged between 16 and 68 years with a median of 38 years. A thorough chart review has been performed with preoperative and postoperative photographs. Duration of hospitalization, complication rate and long term results have been documented.Nine patients had severe burn contracture of axilla, 7 patients had axillary hidradenitis suppurativa, 1 patient had giant neurofibroma of arm, and 1 patient had malignant peripheral nerve sheath tumor of pectoral area. Seventeen flaps survived totally, and in 1 flap, distal superficial slough of skin has been observed. No recurrence in hidradenitis or peripheral nerve sheath tumor has been observed. Donor site scar is well hidden in anatomical position. The range of motion of affected extremities returned to normal after reconstruction.Lateral thoracic area provides a reliable flap option with a wide arc of rotation when lateral thoracic artery perforators are used. PMID:25875722

  19. ["Separation delay" on random flap: an experimental and clinical practice on delayed flap].

    PubMed

    Zhao, S Q

    1990-08-01

    A new technique of delayed flap, that is called "Separation delay" by the authors, has succeeded in animal experiment and clinical practice. In the years of 1985-1989, 11 cases of random skin flaps on the patients had been performed with the new method. All the flaps look like table tennis rackets. It's pedicle is very narrow, simultaneously, the flap itself is very large. So it is quite suitable for repairing a neighbouring wound surface. It can be rotated 180 degrees. "The Separation delay" is a handy way without microsurgical technique. It is also an useful and reliable technique for resurfacing wound on plastic and reconstructive surgery. PMID:2086104

  20. P-47 Thunderbolt with dive recovery flaps

    NASA Technical Reports Server (NTRS)

    1946-01-01

    Caption: 'The dive recovery flaps on this P-47 Thunderbolt are barely visible underneath the wings. Photograph and caption published in Winds of Change, 75th Anniversary NASA publication (pages 52-53 and 130), by James Schultz.

  1. Skin flaps and grafts - self-care

    MedlinePlus

    ... skin infection Surgery for skin cancer Venous ulcers , pressure ulcers , or diabetic ulcers that do not heal After mastectomy or amputation Donor sites for grafts and flaps are chosen ... surgery than the wound due to newly exposed nerve endings.

  2. 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.

  3. 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.

  4. 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

  5. Bilateral pedicled gracilis flap for scrotal reconstruction.

    PubMed

    Daigeler, Adrien; Behr, Björn; Mikhail, Bassem Daniel; Lehnhardt, Marcus; Wallner, Christoph

    2016-09-01

    Trauma, infection and cancer can cause severe scrotal defects. The demand to a definitive reconstruction in terms of aesthetics and function is high. Primary closure, skin grafts and local fasciocutaneous flaps do not meet these high demands in most cases. The authors treated a series of patients requiring scrotal reconstruction with bilateral pedicled gracilis muscle flaps and split thickness skin grafts, resulting in satisfying aesthetic and functional outcomes. PMID:27318782

  6. Dynamic responses of a two-dimensional flapping foil motion

    NASA Astrophysics Data System (ADS)

    Lu, Xi-Yun; Liao, Qin

    2006-09-01

    The investigation of a flapping foil, which is used as a basic mode of the flapping-based locomotion in insects, birds, and fish, is performed by solving the Navier-Stokes equations numerically. In this Brief Communication we provide insight into the understanding of dynamics of a flapping foil. A critical flapping Reynolds number based on the flapping frequency and amplitude, above which a forward flapping movement occurs, is predicted. The dynamics of the flapping foil are analyzed in two dynamic responses, i.e., an oscillatory movement and a steady movement, which depend on the density ratio between the foil and the surrounded fluid. The steady movement response is related to the forward flapping motion. The Strouhal number that governs a vortex shedding for the forward flapping foil is calculated and lies in the range where flying and swimming animals will be likely to tune for high propulsive efficiency.

  7. The Effect of Epigallocatechin Gallate on Flap Viability of Rat Perforator Abdominal Flaps.

    PubMed

    Aksakal, İbrahim Alper; Küçüker, İsmail; Önger, Mehmet Emin; Engin, Murat Sinan; Keleş, Musa Kemal; Demir, Ahmet

    2016-05-01

    Background Epigallocatechin gallate (EGCG) is a substance abundant in green tea. In this study, the effects of EGCG on perforator flap viability were investigated. Methods A total of 40 rats were assigned to four groups of 10 each. In each subject, a 4 × 6 cm abdominal skin flap was raised and adapted back onto its place. In the control group, no further procedures were taken. In the flap group, 40 mg/kg/d EGCG was injected into the flap. In the gavage group, 100 mg/kg/d EGCG was given through a feeding tube. In the intraperitoneal group, 50 mg/kg/d EGCG was injected intraperitoneally. On the 7th postoperative day, flaps were photographed and the viable areas were measured and compared via a one-way analysis of variance. Results The ratios of viable and contracted flap area were 9.15/12.01, 4.59/16.46, 11.56/11.20, and 11.65/10.77 cm(2) for the control, flap group, gavage group, and intraperitoneal group, respectively. While the flap group yielded the worst results in the sense of flap contraction and viability (p < 0.001), the gavage and intraperitoneal groups were significantly better than those of the control group (p = 0.03). Histologically, epidermal, papillary dermal, and capillary tissue volumes were evaluated. In comparison to the control group, the flap group yielded significantly increased epidermal and dermal volumes (p = 0.03), however, these values were significantly decreased (p = 0.04) in the gavage and intraperitoneal groups. Capillary volumes were significantly decreased in EGCG treatment groups (p < 0.01). Conclusion Our experiment has shown that oral and intraperitoneal administration of EGCG increases the perforator flap viability when compared with controls, while direct injection decreases the viability. PMID:26919381

  8. 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

  9. Maxillofacial reconstruction with nasolabial and facial artery musculomucosal flaps.

    PubMed

    Braasch, Daniel Cameron; Lam, Din; Oh, Esther S

    2014-08-01

    The nasolabial and facial artery musculomucosal (FAMM) flaps are predictable methods to reconstruct perioral and intraoral defects with vascularized tissue. The nasolabial flap can be harvested as an axial or random patterned flap, whereas the FAMM flap is truly an axial patterned flap, with either a superior or an inferior base. Both flaps have been widely used to provide predictable results, with low morbidity. Future studies are needed to further prove their use in compromised patients, including patients with a history of head and neck radiation and neck dissections. PMID:25086694

  10. Combined posterior flap and anterior suspended flap dacryocystorhinostomy: A modification of external dacryocystorhinostomy

    PubMed Central

    Deka, Amarendra; Saikia, S. P.; Bhuyan, S. K.

    2010-01-01

    Background: External dacryocystorhinostomy (DCR) remains a reliable surgical technique for the treatment of obstruction of lacrimal drainage system beyond the common canalicular opening. Aim: To describe a simple modified double flap external DCR technique. Materials and Methods: Ninety six consecutive cases of chronic dacryocystitis with or without mucocele were selected irrespective of age and sex. In a modification to routine external DCR, a modified technique was followed, where both anterior and posterior flaps of lacrimal sac and nasal mucosa are created and sutured. Two double armed sutures were used to join the edges of anterior flaps, and elevate them anteriorly to avoid adhesion or apposition with underlying sutured posterior flaps, and to approximate the deep plane of the wound. Results: At the end of average follow-up period of 13 months, we observed 98.9% objective and 96.8% subjective success rates. The average operation time was 45 minutes. No significant intraoperative or postoperative complications were noticed. Conclusion: We believe that combined posterior flap and anterior suspended flap DCR technique is simple to perform and has the advantage of both double flap DCR and anterior suspension of anterior flaps. The results of the study showed the efficacy of this simple modification. PMID:20606867

  11. The evolving breast reconstruction: from latissimus dorsi musculocutaneous flap to a propeller thoracodorsal fasciocutaneous flap

    PubMed Central

    Gunnarsson, Gudjon Leifur

    2014-01-01

    The aim of this editorial is to give an update on the use of the propeller thoracodorsal artery perforator flap (TAP/TDAP-flap) within the field of breast reconstruction. The TAP-flap can be dissected by a combined use of a monopolar cautery and a scalpel. Microsurgical instruments are generally not needed. The propeller TAP-flap can be designed in different ways, three of these have been published: (I) an oblique upwards design; (II) a horizontal design; (III) an oblique downward design. The latissimus dorsi-flap is a good and reliable option for breast reconstruction, but has been criticized for morbidity and complications. The TAP-flap does not seem to impair the function of the shoulder or arm and the morbidity appears to be scarce. However, an implant is often needed in combination with the TAP-flap, which results in implant related morbidity over time. The TAP-flap seems to be a promising tool for oncoplastic and reconstructive breast surgery and will certainly become an invaluable addition to breast reconstructive methods. PMID:25207206

  12. Design and experimental results for a turbine with jet flap stator and jet flap

    NASA Technical Reports Server (NTRS)

    Bettner, J. L.; Blessing, J. O.

    1973-01-01

    The overall performance and detailed stator performance of a negative hub reaction turbine design featuring a moderately low solidity jet flap stator and a jet flap rotor were determined. Testing was conducted over a range of turbine expansion ratios at design speed. At each expansion ratio, the stator jet flow and rotor jet flow ranged up to about 7 and 8 percent, respectively, of the turbine inlet flow. The performance of the jet flap stator/jet flap rotor turbine was compared with that of a turbine which used the same jet flap rotor and a conventional, high solidity plan stator. The effect on performance of increased axial spacing between the jet stator and rotor was also investigated.

  13. 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

  14. 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

  15. 14 CFR 25.701 - Flap and slat interconnection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... equivalent means. (b) If a wing flap or slat interconnection or equivalent means is used, it must be designed... be designed for the loads imposed when the wing flaps or slats on one side are carrying the...

  16. Flapping wing PIV and force measurements

    NASA Astrophysics Data System (ADS)

    Cameron, Benjamin H.

    Flapping wing aerodynamics has been of interest to engineers recently due in part to the DARPA (Defense Advanced Research Projects Agency) MAV (Micro-Aerial Vehicle) initiative. MAVs are small unmanned aerial vehicles with length scales similar to birds and insects. Flapping wing MAVs would serve as mobile and stealthy sensing platforms capable of gathering intelligence in hazardous and physically inaccessible locations. Traditional means of lift and thrust generation become inefficient when scaled to these sizes, therefore a flapping wing propulsion system will be necessary. The design of a flapping wing MAV requires the ability to measure forces and velocities around the wing. Three components of velocity were measured in the wake of a two dimensional (2D) flapping airfoil model using a novel application of stereoscopic DPIV (Digital Particle Image Velocimetry). One component of force was measured using a newly proposed method outlined in the dissertation. The force measurement technique relies on a specific sequence of data acquisition, which has the benefit of reducing measurement uncertainty and noise. No experiments of this type have been conducted, and no direct aerodynamic force data exists for the low Reynolds numbers applicable to flapping wing MAVs. The well-established stereoscopic DPIV technique produces relatively low uncertainties while the new force measurement technique has not been previously tested. Theoretical analysis and experimental results show that aerodynamic forces are attainable for chord Reynolds numbers as low as 1,000, which is significantly lower than previous studies. PIV measurements reveal symmetric and asymmetric wake topologies for a NACA 0012 and flat plate airfoil. A sinusoidally heaving flat plate airfoil produces highly deflected wakes for a wider range of flapping conditions than a NACA 0012 airfoil. Deflected wakes are of potentially interest since both lift and thrust components of force are developed. The flat plate also

  17. 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

  18. 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

  19. 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...

  20. 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...

  1. 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...

  2. Unexpected flap thickness in laser in situ keratomileusis.

    PubMed

    Giledi, Osama; Daya, Sheraz M

    2003-09-01

    We report a case of an unexpected thick flap during laser in situ keratomileusis (LASIK) that led to abandonment of surgery. This report illustrates the importance of stromal bed measurements after flap creation in LASIK. A thicker-than-expected flap can lead to a thinner-than-anticipated residual cornea and subsequent ectasia or even perforation during laser ablation. It is possible that reports of ectasia in normal thickness corneas reflect thicker-than-anticipated flaps. PMID:14522308

  3. 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...

  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. 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.

  6. 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

  7. 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...

  8. 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...

  9. 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...

  10. CHARACTERISTICS OF FLAP GATES AT THE END OF DRAIN PIPES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flap gates are commonly used at the end of pipe drains and pump outlets to prevent back flows of water and entry of small animals. Flap gates are relatively inexpensive, with low maintenance costs, but can trap debris in their hinge systems. Many texts refer to studies performed on flap gates at t...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. Prospective evaluation of outcome measures in free-flap surgery.

    PubMed

    Kelly, John L; Eadie, Patricia A; Orr, David; Al-Rawi, Mogdad; O'Donnell, Margaret; Lawlor, Denis

    2004-08-01

    Free-flap failure is usually caused by venous or arterial thrombosis. In many cases, lack of experience and surgical delay also contribute to flap loss. The authors prospectively analyzed the outcome of 57 free flaps over a 28-month period (January, 1999 to April, 2001). The setting was a university hospital tertiary referral center. Anastomotic technique, ischemia time, choice of anticoagulant, and the grade of surgeon were recorded. The type of flap, medications, and co-morbidities, including preoperative radiotherapy, were also documented. Ten flaps were re-explored (17 percent). There were four cases of complete flap failure (6.7 percent) and five cases of partial failure (8.5 percent). In patients who received perioperative systemic heparin or dextran, there was no evidence of flap failure (p = .08). The mean ischemia time was similar in flaps that failed (95 +/- 29 min) and in those that survived (92 +/- 34 min). Also, the number of anastomoses performed by trainees in flaps that failed (22 percent), was similar to the number in flaps that survived (28 percent). Nine patients received preoperative radiotherapy, and there was complete flap survival in each case. This study reveals that closely supervised anastomoses performed by trainees may have a similar outcome to those performed by more senior surgeons. There was no adverse effect from radiotherapy or increased ischemia time on flap survival. PMID:15356760

  17. Clinical outcomes of suture delay in forehead flap.

    PubMed

    Isik, Daghan; Kiroglu, Faruk; Isik, Yasemin; Goktas, Ugur; Atik, Bekir

    2012-01-01

    The delay phenomenon is a surgical procedure performed to raise a wider skin flap and to improve the survival of skin flaps. Surgery, chemicals, sutures, and lasers can be used for the delay procedure. In this study, delayed forehead flaps created by suturing were used for coverage of nasal skin defects in eleven patients. In 7 patients, the cross-paramedian forehead flap was used to increase the extent of flap lengthening. In the first session, suture delay was performed on both sides of the forehead flap margin. In the second session, the flap was elevated and sutured to its new position, 7 to 10 days after the initial surgery. All flaps were completely viable, and patient satisfaction was optimal in all cases. The positive effect of surgical delay on flap survival has been shown in experimental and clinical studies. However, experimentally, suture delay or chemical delay procedures have been shown to be beneficial in flap survival only. Suture delay seems to be an inexpensive, effective, easily performed, atraumatic, and safe technique, especially among patients with systemic diseases such as diabetes or cardiovascular diseases, smoking patients who may lose the flap, or patients who need very wide and long flaps. PMID:22337378

  18. 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...

  19. 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...

  20. [Andrological complications after pancystoprostatovesiculectomy surgery: utility of the bulbocavernosus reflex].

    PubMed

    Musci, R; Franchini, V; Strada, G; De Cobelli, O; Meroni, T; Sala, M; Rocco, F

    1994-02-01

    The technique for radical cystoprostatectomy was modified to avoid injury to the branches of pelvic plexus that innervate the corpora cavernosa (monolateral neurovascular bundle preservation or "Nerve sparing technique"). The studies of Walsh and coll. demonstrated that the branches of pelvic plexus that innervate the corpora cavernosa are situated between the rectum and urethra and penetrate the urogenital diaphragm near to the muscular wall of the urethra. Injuries to the pelvic plexus can occur during 1) division of posterior pedicle of bladder (the seminal vesicle can be used as a landmark intraoperatively to avoid injury to pelvic plexus), 2) during apical dissection of prostate with transection of the urethra. The return of sexual function postoperatively is related to preservation of autonomic innervation; the excision of the neurovascular bundle on one side may prevent impotence in 68% patients. Our study was undertaken to identify the cause of impotence in men undergoing radical cystoprostatectomy with "Nerve sparing technique" using bulbo cavernous reflex. Our results suggest that bulbo cavernosus reflex may not be a sensitive clinical tool to establish a diagnosis of neurogenic erectile dysfunction after pelvic surgery. The Authors examine the recent neuro-uro-physiological diagnostic methods for the study of neurogenic erectile dysfunction. PMID:8012425

  1. Collective Flow Enhancement by Tandem Flapping Wings.

    PubMed

    Gravish, Nick; Peters, Jacob M; Combes, Stacey A; Wood, Robert J

    2015-10-30

    We examine the fluid-mechanical interactions that occur between arrays of flapping wings when operating in close proximity at a moderate Reynolds number (Re≈100-1000). Pairs of flapping wings are oscillated sinusoidally at frequency f, amplitude θ_{M}, phase offset ϕ, and wing separation distance D^{*}, and outflow speed v^{*} is measured. At a fixed separation distance, v^{*} is sensitive to both f and ϕ, and we observe both constructive and destructive interference in airspeed. v^{*} is maximized at an optimum phase offset, ϕ_{max}, which varies with wing separation distance, D^{*}. We propose a model of collective flow interactions between flapping wings based on vortex advection, which reproduces our experimental data. PMID:26565499

  2. Collective Flow Enhancement by Tandem Flapping Wings

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Peters, Jacob M.; Combes, Stacey A.; Wood, Robert J.

    2015-10-01

    We examine the fluid-mechanical interactions that occur between arrays of flapping wings when operating in close proximity at a moderate Reynolds number (Re ≈100 - 1000 ). Pairs of flapping wings are oscillated sinusoidally at frequency f , amplitude θM, phase offset ϕ , and wing separation distance D*, and outflow speed v* is measured. At a fixed separation distance, v* is sensitive to both f and ϕ , and we observe both constructive and destructive interference in airspeed. v* is maximized at an optimum phase offset, ϕmax, which varies with wing separation distance, D*. We propose a model of collective flow interactions between flapping wings based on vortex advection, which reproduces our experimental data.

  3. 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.

  4. 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...

  5. 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...

  6. 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... for the Double Cover Flap TED ER02JN04.003...

  7. 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...

  8. 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...

  9. 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

  10. Flap-edge aeroacoustic measurements and predictions

    NASA Astrophysics Data System (ADS)

    Brooks, Thomas F.; Humphreys, William M.

    2003-03-01

    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 the prediction models capture much of the physics. 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. The complexity of the directivity results demonstrate the strong role of edge source geometry and frequency in

  11. The trapezius osteomusculocutaneous flap in dogs.

    PubMed

    Philibert, D; Fowler, J D

    1993-01-01

    A pedicled osteomusculocutaneous flap, composed of the cervical part of the trapezius muscle with its overlying skin and the central spine and body of the scapula, was elevated on the prescapular branch of the superficial cervical vascular pedicle in four dogs. The flap was replaced in an orthotopic location. Bone viability was evaluated using histology, fluorescence bone labeling, and angiography. Bone from the scapular spines had a high percentage of viable osteocytes, positive fluorescence, and vessels were outlined in the angiographic study. Bone from the body of the scapula was not viable based on similar criteria. PMID:8116199

  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. [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

  14. Long term follow up of neurovascular island flaps.

    PubMed

    Henderson, H P; Reid, D A

    1980-06-01

    The results of a ten year mean follow up of twenty Neurovascular Island Flaps and two Radial Nerve Innervated Cross Finger Flaps are presented. Sensory acuity sufficient for tactile gnosis was achieved in nineteen cases. In only one case had sensory acuity deteriorated since operation. Use of the flap was hampered in one patient by a pre-existing neuroma. Complete sensory reorientation occurred in five patients. Sensory misreference persisted more commonly on dominant hands. It was our impression that Porter's Letter Test revealed the patients making most use of their neurovascular island flaps. The place of neurovascular island flaps in the management of the mutilated hand is discussed. PMID:7409615

  15. Propeller thoracodorsal artery perforator flap for breast reconstruction

    PubMed Central

    Angrigiani, Claudio; Escudero, Ezequiel; Artero, Guillermo; Gercovich, Gustavo; Deza, Ernesto Gil

    2014-01-01

    Background The thoracodorsal artery perforator (TDAP) flap has been described for breast reconstruction. This flap requires intramuscular dissection of the pedicle. A modification of the conventional TDAP surgical technique for breast reconstruction is described, utilizing instead a propeller TDAP flap. The authors present their clinical experience with the propeller TDAP flap in breast reconstruction alone or in combination with expanders or permanent implants. Methods From January 2009 to February 2013, sixteen patients had breast reconstruction utilizing a propeller TDAP flap. Retrospective analysis of patient characteristics, clinical indications, procedure and outcomes were performed. The follow-up period ranged from 4 to 48 months. Results Sixteen patients had breast reconstruction using a TDAP flap with or without simultaneous insertion of an expander or implant. All flaps survived, while two cases required minimal resection due to distal flap necrosis, healing by second intention. There were not donor-site seromas, while minimal wound dehiscence was detected in two cases. Conclusions The propeller TDAP flap appears to be safe and effective for breast reconstruction, resulting in minimal donor site morbidity. The use of this propeller flap emerges as a true alternative to the traditional TDAP flap. PMID:25207210

  16. The keystone flap: expanding the dermatologic surgeon's armamentarium.

    PubMed

    Hessam, Schapoor; Sand, Michael; Bechara, Falk G

    2015-01-01

    First described in 2003, the keystone flap has become an established plastic and reconstructive surgery technique for the closure of soft tissue defects following the excision of skin tumors. Complex reconstruction procedures may thus be avoided [3]. In dermatosurgery, however, the keystone flap remains largely unknown.Compared to subcutaneous pedicle flaps, the keystone flap technique warrants better vascular supply by additional-ly preserving musculocutaneous and fasciocutaneous perforator vessels [4]. Moreover, the flap is hyperemic compared to the surrounding skin [5]. Adequate perfusion and its specific design result in high safety of the flap. According to both published data and the authors’ experience, the keystone flap technique is associated with a low complication rate [1, 6].In summary, the keystone flap method yields good aesthetic and functional results by preserving shape and cont-our, avoiding differences in skin coloration and preserving sensitivity (Figure 1b). The flap is particularly well suited for deep defects with exposed bones or tendons, especially on the extremities or the trunk. Alternative closing options such as secondary intention healing, primary closure, or local flaps appear less adequate in these cases. In addition, skin grafting without long-term wound conditioning–for example negative pressure wound therapy–or expensive der-mal replacement products are not very promising. Thus, the keystone flap provides the dermatosurgeon with an effective alternative to reconstruction techniques. PMID:25640508

  17. 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

  18. Delineation of LASIK Flaps with Prednisolone Acetate Eyedrops

    PubMed Central

    Fahd, Daoud C; Fahed, Sharbel D

    2014-01-01

    We describe the use and safety of prednisolone acetate eyedrops at the end of laser in situ keratomileusis (LASIK) to aid proper positioning of the corneal flap. The LASIK flap is created using the preferred technique. Following laser ablation and flap repositioning, one drop of prednisolone acetate is instilled on the eye. This delineates the flap “gutters” and allows perfect flap positioning and centration. We used this technique in 425 eyes undergoing LASIK for correction of spherocylindrical refractive errors. Flap margins were adequately delineated intraoperatively. The only complication related to the use of the steroid suspension was crystal deposition under the flap in one case which resolved completely in 48 hours. PMID:24982743

  19. Aerodynamic characteristics of NACA 4412 airfoil sction with flap

    NASA Astrophysics Data System (ADS)

    Ockfen, Alex E.; Matveev, Konstantin I.

    2009-09-01

    Wing-in-Ground vehicles and aerodynamically assisted boats take advantage of increased lift and reduced drag of wing sections in the ground proximity. At relatively low speeds or heavy payloads of these craft, a flap at the wing trailing-ground-effect flow id numerically investigated in this study. The computational method consists of a steady-state, incompressible, finite volume method utilizing the Spalart-Allmaras turbulence model. Grid generation and solution of the Navier-Stokes equations are completed flow with a flap, as well as ground-effect motion without a flap. Aerodynamic forces are plain flap. Changes in the flow introduced with the flap addition are also discussed. Overall, the use of a flap on wings with small attack angles is found to be beneficial for small flap deflections up to 5% of the chord, where the contribution of lift augmentation exceeds the drag increase, yielding an augmented lift-to-drag ratio

  20. The double opposing myomucosal cheek flap in hard palate reconstruction.

    PubMed

    Pabiszczak, Maciej; Banaszewski, Jacek; Pastusiak, Tomasz; Buczkowska, Agata; Wierzbicka, Małgorzata

    2015-01-01

    Limited defects in the oral cavity can be treated with local and pedicled cheek flaps. It allows to preserve the functions of the resected organ. Large defects in the midline of the hard palate can be reconstructed with double opposing myomucosal cheek flaps. The aim of this study was to discuss the methodology of the flap harvest and to show our experiences of treatment in a group of 15 patients with oral cavity cancer. In 1 patient the double opposing myomucosal cheek flap was harvested due to the wider local defect. The small size of the flap with ability to use the double opposing cheek flap in more extended defects as well as short duration of the surgery procedure can lead to reduced risk of postoperative complications. Finally, cheek flaps form an effective method of treatment of defects in the oral cavity. PMID:26388355

  1. The comparative study on the flapping motion of Venusian magnetotail

    NASA Astrophysics Data System (ADS)

    Rong, Zhaojin; Barabash, Stas; Wieser Stenberg, Gabriella; Futaana, Yoshifumi; Wan, Weixing; Wei, Yong; Wang, Xiaodong; Chai, Lihui; Zhong, Jun

    2016-04-01

    With a newly developed technique and magnetic field measurements obtained by the magnetometer on Venus Express, we study the flapping motion of the Venusian magnetotail. We find that the flapping motion generally comprises contributions both from a nonpropagating steady flapping and a propagating kink-like flapping. The flapping motion tilts the current sheet normal significantly in the plane perpendicular to the Venus-Sun line. The kink-like flapping waves traveling along solar wind electric field or its antidirection can be found in either magnetotail hemisphere where solar wind electric field pointing toward/away. The traveling behaviors suggest that the locations of the triggers for kink-like flappings are near the boundaries between magnetotail current sheet and magnetosheath, not near the central region of magnetotail as is for the Earth's magnetotail.

  2. The split radial forearm flap for lower leg defects.

    PubMed

    van Kampen, Robert J; Corten, Eveline M L; Schellekens, Pascal P A

    2014-11-01

    The conventional free radial forearm flap is a very reliable, long-pedicled flap with thin, pliable skin. These properties make it an excellent choice for high-risk reconstructions or defects requiring only a thin cover. The split radial forearm flap allows primary closure of the donor site and has a large variability in shape and size. In this report, the cutaneous perforators of the radial artery were investigated in fresh cadavers and we present our clinical experience with the split radial artery flap in 9 patients with lower leg defects. Sufficient perforators exist to safely divide the flap proximally and distally into segments. In all clinical cases, the donor site could be closed primarily. All flaps remained viable and 8 of 9 patients obtained an esthetically pleasing result. The split radial forearm free flap is an elegant option for reconstruction of small- to moderate-sized soft tissue defects in the lower extremity. PMID:23657049

  3. Tubularized Penile-Flap Urethroplasty Using a Fasciocutaneous Random Pedicled Flap for Recurrent Anterior Urethral Stricture

    PubMed Central

    Lee, Byung Kwon

    2012-01-01

    This report describes the use of a tubularized random flap for the curative treatment of recurrent anterior urethral stricture. Under the condition of pendulous lithotomy and suprapubic cystostomy, the urethral stricture was removed via a midline ventral penile incision followed by elevation of the flap and insertion of an 18-Fr catheter. Subcutaneous buried interrupted sutures were used to reapproximate the waterproof tubularized neourethra and to coapt with the neourethra and each stump of the urethra, first proximally and then distally. The defect of the penile shaft was covered by advancement of the surrounding scrotal flap. The indwelling catheter was maintained for 21 days. A 9 month postoperative cystoscopy showed no flap necrosis, no mechanical stricture, and no hair growth on the lumen of the neourethra. The patient showed no voiding discomfort 6 months after the operation. The advantages of this procedure are the lack of need for microsurgery, shortening of admission, the use of only spinal anesthesia (no general anesthesia), and a relatively short operative time. The tubularized unilateral penile fasciocutaneous flap should be considered an option for initial flap urethroplasty as a curative technique. PMID:22783537

  4. The "open book" flap: a heterodigital cross-finger skin flap and adipofascial flap for coverage of a circumferential soft tissue defect of a digit.

    PubMed

    Tadiparthi, S; Akali, A; Felberg, L

    2009-02-01

    A case of circumferential digital skin loss with exposed tendons from the proximal phalanx to the distal interphalangeal joint is presented. This was treated with a two-layer heterodigital cross-finger ("open book") flap from the adjacent digit, utilising a skin-only cross-finger flap to cover the palmar defect and an adipofascial flap to cover the dorsal defect. PMID:19129359

  5. Microsurgery flap in endodontic surgery: case report

    PubMed Central

    CECCHETTI, F.; RICCI, S.; DI GIORGIO, G.; PISACANE, C.; OTTRIA, L.

    2009-01-01

    SUMMARY In periodontal plastic surgery it is increasingly more evident the relavance of the protection of the gingival marginal anatomy through the realization of a conservative flap. Minimizing the recession of the treated tissue. A correct healing always needs to take into account the diameter and type of the suture and the time of removal from the wound. PMID:23285354

  6. Neural Anatomy of the Anterolateral Thigh Flap.

    PubMed

    Luenam, Suriya; Prugsawan, Krit; Kosiyatrakul, Arkaphat; Chotanaphuti, Thanainit; Sriya, Piyanee

    2015-06-01

    The anterolateral thigh (ALT) flap is one of the commonly used sensate flaps for intra-oral, hand, and foot reconstruction. The objective of this study was to describe the anatomic location of the sensory nerves supplying the ALT flap in relation to the surface landmarks and with the vascular pedicles. The dissections were carried out in 28 embalmed specimens. An axial line from the anterior superior iliac spine to the superolateral border of the patella and two circles with radii of 5 and 10 cm centered on the midpoint of the former line were used for the surface landmarks. At the intersection point of the axial line and the 10-cm circle, the main lateral femoral cutaneous nerve (LFCN) and its anterior branch were located within 1 and 2.4 cm, respectively. At the intersection point of the axial line and the 5-cm circle, the anterior branch of the LFCN was located within 2.8 cm. The anterior branch of the LFCN can be detected within 3 cm from the central perforator pedicle in all specimens. The posterior branch of the LFCN, superior perforator nerve, and median perforator nerve were found in more variable locations. The findings from our study provide additional information for clinical use in the planning of sensate ALT flap harvest. PMID:26078503

  7. Correlation of Smart Active Flap Rotor Loads

    NASA Technical Reports Server (NTRS)

    Kottapalli, Sesi; Straub, Friedrich

    2009-01-01

    The ability to predict SMART active trailing edge flap rotor loads is explored in this study. Full-scale wind tunnel data recently acquired in the NASA Ames 40- by 80- Foot Wind Tunnel are compared with analytical results from CAMRAD II. For the 5-bladed rotor, two high-speed forward flight cases are considered, namely, a 0 deg flap deflection case and a 5P, 2 deg flap deflection case. Overall, the correlation is reasonable, with the following exceptions: the torsion moment frequency and the chordwise bending moment are under predicted. In general, the effect of the 5P, 2 deg flap motion is captured by the analysis, though there is over prediction in the neighborhood of the 105 deg and 120 deg azimuthal locations. Changes to the flexbeam torsion stiffness are also briefly considered in this study, as this stiffness will be updated in the future. Finally, the indication is that compressibility effects are important, and this suggests that computational fluid dynamics might improve the current correlation.

  8. Periodic and chaotic flapping of insectile wings

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Kanso, E.

    2015-11-01

    Insects use flight muscles attached at the base of the wings to produce impressive wing flapping frequencies. The maximum power output of these flight muscles is insufficient to maintain such wing oscillations unless there is good elastic storage of energy in the insect flight system. Here, we explore the intrinsic self-oscillatory behavior of an insectile wing model, consisting of two rigid wings connected at their base by an elastic torsional spring. We study the wings behavior as a function of the total energy and spring stiffness. Three types of behavior are identified: end-over-end rotation, chaotic motion, and periodic flapping. Interestingly, the region of periodic flapping decreases as energy increases but is favored as stiffness increases. These findings are consistent with the fact that insect wings and flight muscles are stiff. They further imply that, by adjusting their muscle stiffness to the energy level at which they are operating, insects can maintain periodic flapping mechanically for a range of operating conditions.

  9. Computation of Lifting Wing-Flap Configurations

    NASA Technical Reports Server (NTRS)

    Cantwell, Brian; Kwak, Dochan

    1996-01-01

    Research has been carried out on the computation of lifting wing-flap configurations. The long term goal of the research is to develop improved computational tools for the analysis and design of high lift systems. Results show that state-of-the-art computational methods are sufficient to predict time-averaged lift and overall flow field characteristics on simple high-lift configurations. Recently there has been an increased interest in the problem of airframe generated noise and experiments carried out in the 7 x 10 wind tunnel at NASA Ames have identified the flap edge as an important source of noise. A follow-on set of experiments will be conducted toward the end of 1995. The computations being carried out under this project are coordinated with these experiments. In particular, the model geometry being used in the computations is the same as that in the experiments. The geometry consists of a NACA 63-215 Mod B airfoil section which spans the 7 x lO tunnel. The wing is unswept and has an aspect ratio of two. A 30% chord Fowler flap is deployed modifications of the flap edge geometry have been shown to be effective in reducing noise and the existing code is currently being used to compute the effect of a modified geometry on the edge flow.

  10. Peritoneal flap ureteropexy for idiopathic retroperitoneal fibrosis.

    PubMed

    Fowler, J W

    1987-07-01

    Eight patients had 13 ureters treated by peritoneal flap ureteropexy. There were no significant post-operative complications. Eleven ureters were functioning normally after an average follow-up of 28 months. The operation is suggested as a method of choice where omental wrapping is not possible. PMID:3620842

  11. Free Surface and Flapping Foil Interactions

    NASA Astrophysics Data System (ADS)

    Ananthakrishnan, Palaniswamy

    2014-11-01

    Flapping foils for station-keeping of a near-surface body in a current is analyzed using a finite-difference method based on boundary-fitted coordinates. The foils are hinge-connected to the aft of the body and subject to pitch oscillation. Results are obtained for a range of Strouhal number, Froude number, unsteady frequency parameter τ, Reynolds number and the depth of foil submergence. Results show that at low Strouhal number (St < 0 . 1) and sub-critical unsteady parameter τ < 0 . 25 , the flapping generates drag instead of thrust. At high Strouhal number and super-critical value of the unsteady parameter (τ > 0 . 25) flapping generates high thrust with low efficiency. Thrust and efficiency are found to decrease with decreasing submergence depth of the foil. At the critical τ = 0 . 25 and shallow submergence of the foil, the standing wave generated above the foil continues to grow until breaking; both the thrust and efficiency of the foil are reduced at the critical τ. The necessary conditions for optimal thrust generation by a flapping foil underneath the free surface are found to be (i) Strouhal number in the range from 0.25 to 0.35, (ii) unsteady parameter τ > 0 . 25 and (iii) the maximum angle of attack less than 15° for the flat-plate foil. Supported by the US Office of Naval Research through the Naval Engineering Education Center (NEEC) Consortium of the University of Michigan, Ann Arbor.

  12. 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

  13. High-energy war wounds: flap reconstruction.

    PubMed

    Stanec, Z; Skrbić, S; Dzepina, I; Hulina, D; Ivrlac, R; Unusić, J; Montani, D; Prpić, I

    1993-08-01

    In this article, we emphasize that knowledge of terminal ballistics is essential for understanding the pathophysiology of war wounds. We present our own experiences in treatment of high-energy war wounds in 75 patients treated in the Institute of Plastic and Reconstructive Surgery, Department of Surgery, Clinical Hospital Center in Zagreb. Patients were divided into three groups with regard to the time of definite reconstruction, using local or free microvascular flaps. About 12% of patients underwent flap reconstruction in the acute phase, associated with low complication rate and the shortest hospital stay. Group II was comprised by 18% of the patients and, considering the number of complications, presented the most unfavorable time for reconstruction. Flap reconstruction in the chronic phase resulted in a substantial prolongation of the hospital stay in 82% of patients. Therefore, we advocate proper primary treatment of wounds aimed at early flap closure. This type of management results in a significantly shorter hospitalization and leads to more effective rehabilitation and recovery of patients. PMID:8215140

  14. Unilateral Breast Reconstruction Using Bilateral Inferior Gluteal Artery Perforator Flaps

    PubMed Central

    Muto, Mayu; Ogawa, Marina; Shibuya, Mai; Yasumura, Kazunori; Kobayashi, Shinji; Ishikawa, Takashi; Maegawa, Jiro

    2015-01-01

    Background: For reconstructing moderate-to-high projection breasts in nulliparous patients with insufficient abdominal tissue or prior abdominal surgeries, a unilateral inferior gluteal artery perforator (IGAP) flap is an alternative procedure. In patients with slim hips, however, unilateral gluteal tissue is insufficient and inferior gluteal crease displacement may develop postoperatively. Donor-site asymmetry is also a major disadvantage. In these circumstances, bilateral IGAP flaps provide sufficient tissue without significant gluteal deformity. Methods: We retrospectively reviewed 20 patients who underwent unilateral breast reconstruction using bilateral IGAP flaps by a single surgeon between November 2007 and December 2012. A quantitative outcome assessment was performed and compared with that of 22 unilateral IGAP flap patients operated on by the same surgeon. Results: Twenty patients underwent reconstruction with 40 IGAP flaps. Of the 40 flaps, 39 survived and 1 developed total necrosis due to repeated venous thrombosis. In 15 of 20 patients, the size of reconstructed breast was comparable to that of the contralateral breast. Final inset flap weight was 462.3 g for bilateral flaps and 244.3 g for unilateral flaps. Total operating time was 671.1 minutes (bilateral flaps) and 486.8 minutes (unilateral flaps). Conclusions: Use of bilateral IGAP flaps for breast reconstruction helps to avoid asymmetry of the inferior buttock volume and shape. Bilateral flaps provide sufficient tissue volume and allow for reconstruction of a breast comparable to the unaffected side. In patients with moderate-to-high projection breast whose abdominal tissue cannot be used for reconstruction, IGAP flaps may be a suitable alternative. PMID:25878925

  15. 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

  16. 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

  17. The Retrograde Ulnar Dorsal Flap: Surgical Technique and Experience as Island Flap in Coverage of Hand Defects.

    PubMed

    Vergara-Amador, Enrique

    2015-09-01

    Flaps from the forearm are often used to reconstruct soft-tissue defects in the hand. The retrograde ulnar dorsal flap has the advantage that it does not sacrifice a major vascular axis. The anatomic bases of this flap are the proximal and distal branch of the ulnar dorsal artery. The distal branch is partially accompanied with the dorsal branch of the ulnar nerve, and arrives under the abductor digiti quinti muscle making anastomoses with the deep branch of the ulnar artery. The proximal branch reaching the proximal third of the forearm, and anastomose with perforating branches of the ulnar artery. I used this island flap in 12 patients with coverage defects on the hand. The biggest flap was 13×6 cm. Only 1 flap had partial necrosis which did not lead to problems. The retrograde ulnar dorsal flap is a flap designed with reverse flow from the distal branch of the ulnar dorsal artery, and which does not sacrifice the ulnar artery. The donor defect on the forearm ulnar side had a greater esthetic acceptance. Knowing other distal anastomoses, described by other authors later, dorsal at the base of the fourth interdigital space grant greater security to the retrograde ulnar dorsal flap. It is worth highlighting the importance of preserving the adipofascial tissue around the pedicle. Experience with this flap permits us to state that it is a safe and reproducible flap to cover any defect on the dorsal of the hand as well as the first web space. PMID:26079665

  18. Assessing safety of negative-pressure wound therapy over pedicled muscle flaps: A retrospective review of gastrocnemius muscle flap.

    PubMed

    Lance, Samuel; Harrison, Lindsey; Orbay, Hakan; Boudreault, David; Pereira, Gavin; Sahar, David

    2016-04-01

    The use of negative-pressure wound therapy (NPWT) for management of open wounds and immobilization of split-thickness skin grafts (STSGs) over wounds has been well described. However, there is a concern for potential compromise of flap viability when NPWT is used for skin grafts over pedicled muscle flaps. We have used NPWT to immobilize STSGs in eight patients who underwent a pedicled gastrocnemius muscle flap operation in our department. We applied a negative pressure of -75 mmHg on the muscle flaps for 5 days postoperatively. All wounds healed successfully, with a 97.5 ± 5.5% mean STSG uptake. No flap necrosis was observed. In our series, the use of NPWT for fixation of STSGs over pedicled gastrocnemius muscle flap was effective and had no negative impact on flap viability. PMID:26732293

  19. Wing loading on a 60 degree delta wing with vortex flaps

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    Wind tunnel tests were conducted on a 60 deg delta wing with three vortex flap designs to determine pressure distributions over the wing and flap. The results showed that an optimum vortex flap design depends on proper definition of the vortex flap deflection angle. They also revealed that flap thickness plays an important role in the behavior of the vortex flow over the flap and wing and can have a substantial effect on wing and flap pressure loading. Design codes which fail to account for thickness may result in a much less than optimum flap and deprive the designer of an important tool in designing an effective flap with optimum loading.

  20. Pedicle versus free flap reconstruction in patients receiving intraoperative brachytherapy.

    PubMed

    Geiger, Erik J; Basques, Bryce A; Chang, Christopher C; Son, Yung; Sasaki, Clarence T; McGregor, Andrew; Ariyan, Stephan; Narayan, Deepak

    2016-08-01

    Introduction This study compared complication rates between pedicle flaps and free flaps used for resurfacing of intraoperative brachytherapy (IOBT) implants placed following head and neck tumour extirpation to help clarify the ideal reconstructive procedure for this scenario. Patients and methods A retrospective review of reconstructions with IOBT at our institution was conducted. Patient and treatment details were recorded, as were the number and type of flap complications, including re-operations. Logistic regressions compared complications between flap groups. Results Fifty free flaps and 55 pedicle flaps were included. On multivariate analysis, free flap reconstruction with IOBT was significantly associated with both an increased risk of having any flap complication (OR = 2.9, p = 0.037) and with need for operative revision (OR = 3.5, p = 0.048) compared to pedicle flap reconstruction. Conclusions In the setting of IOBT, free flaps are associated with an increased risk of having complications and requiring operative revisions. PMID:26983038

  1. Repeated Elevation of the Anterolateral Thigh Flap for Lower Extremity Orthopedic Trauma Does Not Affect Flap Viability.

    PubMed

    Kotick, James D; Mitchell, William; Bayouth, Lilly; Klein, Richard; Lee, Ken

    2016-03-01

    Background The anterolateral thigh (ALT) flap has a key role regarding limb salvage and has facilitated the preservation of function and esthetics in lower extremity reconstruction. The purpose of this study is to review the advantages of the ALT flap when used early in the reconstruction of the trauma patient; specifically, its long-term viability when ALT flap reconstruction is followed by recurrent flap elevation performed to allow a variety of sequential orthopedic operations including washout, antimicrobial disc placement, and reinstrumentation. Methods A retrospective analysis was performed to review all ALT flaps performed by the authors from January 2009 to October 2012 at the Orlando Regional Medical Center. A total of 69 patients with an average age of 38 years were included in the study leading to a total of 69 ALT flaps indicated for traumatic orthopedic wounds. Out of these, 29 flaps were elevated at least once leading to a total of 49 flap elevations. Results The median number of days to flap elevation was 117 with a minimum of 1 day and a maximum of 540 days. A total of 42% flaps were elevated at least once after initial placement for reinstrumentation, washout, or antibiotic disk placement. Overall, 52% of the flaps were lifted once, 34% were lifted twice, and 14% were lifted more than thrice. There is no statistically significant difference in the complication rate between elevating the flap compared with primary ALT placement. Conclusion We conclude, therefore, there is no elevated risk to long-term viability by elevating the ALT flap. This combined with the ease of elevation makes it a safe procedure to be performed as needed for access to the deep tissues. PMID:26382873

  2. Canine lateral thoracic fasciocutaneous flap: an experimental study.

    PubMed

    Trinh, Cao Minh; Hoàng, Văn Lu'o'ng; Pham, Thi Ngoc; Hoàng, Manh An

    2009-10-01

    For the purpose of reconstructive surgery training and research, we have developed a new skin flap model: canine lateral thoracic fasciocutaneous flap. Anatomical study found that the lateral thoracic arteries in dogs have similar anatomical characteristics to human's ones. Based on these vessels, if a skin flap was designed within the vessels territory (size 5 x 8 cm) it could survive completely, whereas, if designed beyond the vessels territory (size 5 x 14 cm) would result in partial necrosis of the flap. This fasciocutaneous flap model closely simulates the human surgery and could be valuable for training and research. Furthermore, this flap could be applied in the veterinary practice for reconstruction of canine forelimbs and cervical area. PMID:19638323

  3. 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

  4. Vertical electrostatically 90° turning flaps for reflective MEMS display

    NASA Astrophysics Data System (ADS)

    Jutzi, Fabio; Noell, Wilfried; de Rooij, Nico F.

    2011-03-01

    A new kind of MEMS reflective display is being developed having high contrast and reflectivity, better than on printed paper. The system is based on novel vertical flaps, which can be electrostatically turned by 90° to horizontal position. After fabrication, the poly-silicon flaps are vertical to the wafer surface and on the top suspended by torsion beams. In this state the pixel is black, incoming ambient light passes by the flaps and is absorbed by an underlying absorptive layer. When the flaps are turned to horizontal position light is reflected back and the pixel gets white. A self-aligning four masks bulk microfabrication process is employed, which uses poly-silicon filling of high aspect-ratio cavities. Parylene was also employed as flap material. Thanks to auto stress-compensation the flaps are not deformed due to intrinsic stresses. Low actuation voltages down to 20V can be achieved.

  5. Flap Necrosis after Palatoplasty in Patients with Cleft Palate

    PubMed Central

    Rossell-Perry, Percy

    2015-01-01

    Palatal necrosis after palatoplasty in patients with cleft palate is a rare but significant problem encountered by any cleft surgeon. Few studies have addressed this disastrous complication and the prevalence of this problem remains unknown. Failure of a palatal flap may be attributed to different factors like kinking or section of the pedicle, anatomical variations, tension, vascular thrombosis, type of cleft, used surgical technique, surgeon's experience, infection, and malnutrition. Palatal flap necrosis can be prevented through identification of the risk factors and a careful surgical planning should be done before any palatoplasty. Management of severe fistulas observed as a consequence of palatal flap necrosis is a big challenge for any cleft surgeon. Different techniques as facial artery flaps, tongue flaps, and microvascular flaps have been described with this purpose. This review article discusses the current status of this serious complication in patients with cleft palate. PMID:26273624

  6. Dynamics of Flapping Flag in Axial Flow

    NASA Astrophysics Data System (ADS)

    Abderrahmane, Hamid Ait; Fayed, Mohamed; Gunter, Amy-Lee; Paidoussis, Michael P.; Ng, Hoi Dick

    2010-11-01

    We investigate experimentally the phenomenon of the flapping of a flag, placed within a low turbulent axial flow inside a small scale wind tunnel test section. Flags of different sizes and flexural rigidities were used. Image processing technique was used and the time series of a given point on the edge of the flag was analyzed. The stability condition of the flag was obtained and compared to the recent theoretical models and numerical simulations. Afterwards, the nonlinear dynamics of the flapping was investigated using nonlinear time series method. The nonlinear dynamics is depicted in phase space and the correlation dimension of the attractors is determined. On the basis of observations made in this study, some conclusions on the existing models were drawn.

  7. 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.

  8. Flap Coverage of Anterior Abdominal Wall Defects

    PubMed Central

    Sacks, Justin M.; Broyles, Justin M.; Baumann, Donald P.

    2012-01-01

    Reconstruction of complex defects of the anterior abdomen is both challenging and technically demanding for reconstructive surgeons. Advancements in the use of pedicle and free tissue transfer along with the use of bioprosthetic and synthetic meshes have provided for novel approaches to these complex defects. Accordingly, detailed knowledge of abdominal wall and lower extremity anatomy in combination with insight into the design, implementation, and limitations of various flaps is essential to solve these complex clinical problems. Although these defects can be attributed to a myriad of etiologic factors, the objectives in abdominal wall reconstruction are consistent and include the restoration of abdominal wall integrity, protection of intraabdominal viscera, and the prevention of herniation. In this article, the authors review pertinent anatomy and the various local, regional, and distant flaps that can be utilized in the reconstruction of these complex clinical cases of the anterior abdomen. PMID:23372457

  9. 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.

  10. 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.

  11. 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.

  12. The angel flap for nipple reconstruction

    PubMed Central

    Wong, Wendy W; Hiersche, Matthew A; Martin, Mark C

    2013-01-01

    Creation of an aesthetically pleasing nipple plays a significant role in breast reconstruction as a determining factor in patient satisfaction. The goals for nipple reconstruction include minimal donor site morbidity and appropriate, long-lasting projection. Currently, the most popular techniques used are associated with a significant loss of projection postoperatively. Accordingly, the authors introduce the angel flap, which is designed to achieve nipple projection with lasting results. The lateral edges of the flap and the area surrounding the top of the nipple are de-epithelialized and the flaps are wrapped to create a nipple mound composed primarily of dermis. Decreasing the amount of fat within core of the nipple and enhancing dermal content promotes long-lasting projection. Furthermore, the incision pattern fits within a desired areolar size, preventing unnecessary superfluous extension of the incisions. Thus, the technique described herein achieves the goals of nipple reconstruction, including adequate and long-lasting projection, without extension of the lateral limb scars. PMID:24431944

  13. 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.

  14. Global optimization of actively morphing flapping wings

    NASA Astrophysics Data System (ADS)

    Ghommem, Mehdi; Hajj, Muhammad R.; Mook, Dean T.; Stanford, Bret K.; Beran, Philip S.; Snyder, Richard D.; Watson, Layne T.

    2012-08-01

    We consider active shape morphing to optimize the flight performance of flapping wings. To this end, we combine a three-dimensional version of the unsteady vortex lattice method (UVLM) with a deterministic global optimization algorithm to identify the optimal kinematics that maximize the propulsive efficiency under lift and thrust constraints. The UVLM applies only to incompressible, inviscid flows where the separation lines are known a priori. Two types of morphing parameterization are investigated here—trigonometric and spline-based. The results show that the spline-based morphing, which requires specification of more design variables, yields a significant improvement in terms of propulsive efficiency. Furthermore, we remark that the average value of the lift coefficient in the optimized kinematics remained equal to the value in the baseline case (without morphing). This indicates that morphing is most efficiently used to generate thrust and not to increase lift beyond the basic value obtained by flapping only. Besides, our study gives comparable optimal efficiencies to those obtained from previous studies based on gradient-based optimization, but completely different design points (especially for the spline-based morphing), which would indicate that the design space associated with the flapping kinematics is very complex.

  15. 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.

  16. Locomotion of a flapping flexible plate

    NASA Astrophysics Data System (ADS)

    Hua, Ru-Nan; Zhu, Luoding; Lu, Xi-Yun

    2013-12-01

    The locomotion of a flapping flexible plate in a viscous incompressible stationary fluid is numerically studied by an immersed boundary-lattice Boltzmann method for the fluid and a finite element method for the plate. When the leading-edge of the flexible plate is forced to heave sinusoidally, the entire plate starts to move freely as a result of the fluid-structure interaction. Mechanisms underlying the dynamics of the plate are elucidated. Three distinct states of the plate motion are identified and can be described as forward, backward, and irregular. Which state to occur depends mainly on the heaving amplitude and the bending rigidity of the plate. In the forward motion regime, analysis of the dynamic behaviors of the flapping flexible plate indicates that a suitable degree of flexibility can improve the propulsive performance. Moreover, there exist two kinds of vortex streets in the downstream of the plate which are normal and deflected wake. Further the forward motion is compared with the flapping-based locomotion of swimming and flying animals. The results obtained in the present study are found to be consistent with the relevant observations and measurements and can provide some physical insights into the understanding of the propulsive mechanisms of swimming and flying animals.

  17. Theoretical and experimental study on the ejector augmented jet flap

    NASA Technical Reports Server (NTRS)

    Stewart, H. J.

    1974-01-01

    The analytical concept used in determining the characteristics of jet flap or related propulsive systems suitable for VTOL and STOL applications was examined. The configuration chosen was a two dimensional wing with a biplane flap, having a jet injected on the upper surface of the wing at the flap hinge axis and discharging into the channel between the two elements of the flap. The experimental work was conducted in a two dimensional test installation in a subsonic wind tunnel. The model description, the test conditions, and a summary of the experimental results are presented.

  18. [Superficial ulnar artery while harvesting a radial forearm flap].

    PubMed

    Moullot, P; Gay, A-M; Guidicelli, T; Rouabah, K; Legré, R

    2015-02-01

    Forearm vascular anatomical variations are common and may have complications during flaps harvesting. This article describes the presence of an ulnar superficial artery, revealed while harvesting a radial forearm flap. The prevalence of this anatomical variation is between 0.7 and 9.4%. It may have important consequences while covering loss of substance with a radial forearm flap. Unknown, there is a risk of vascular injury which may lead to distal ischemia of the upper limb. Preoperative diagnosis can anticipate this risk and harvest a fascio-cutaneous flap centered on a perforator of this artery. PMID:24095106

  19. 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.

  20. 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

  1. Computational Investigation of a Semi-Span Flap

    NASA Technical Reports Server (NTRS)

    Mathias, Donovan, L.; Roth, Karlin R.; Ross, James C.; Rogers, Stuart E.; Cummings, Russell M.; Olson, Lawrence E. (Technical Monitor)

    1995-01-01

    The current study computationally examines one of the principle three-dimensional features of the flow over a high-lift system, the flow associated with a flap edge. Structured, overset grids were used in conjunction with an incompressible Navier-Stokes solver to compute the flow over a two-element high-lift configuration. The computations were run in a fully turbulent mode using the one-equation Baldwin-Barth model. Specific interest was given to the details of the flow in the vicinity of the flap edge, so the geometry was simplified to isolate this region. The geometry consisted of an unswept wing, which spanned a wind tunnel test section, equipped with a single element flap. Two flap configurations were computed; a full-span and a half-span Fowler flap. The chord based Reynolds number was 3.7 million for all cases. The results for the full-span flap agreed with two-dimensional experimental results and verified the method. Grid topologies and related issues for the half-span flap geometry are discussed. Results of the half-span flap case are presented with emphasis on the flow features associated with the flap edge.

  2. Flap noise characteristics measured by pressure cross correlation techniques

    NASA Astrophysics Data System (ADS)

    Miller, W. R.

    1980-03-01

    The aerodynamic sound generated by a realistic aircraft flap system was investigated through the use of cross correlations between surface pressure fluctuations and far field sound. Measurements were conducted in two subsonic wind tunnel studies to determine the strength, distribution, and directivity of the major sources of flap noise at speeds up to 79.0 m/sec. A pilot study was performed on a single flap model to test the measurement technique and provide initial data on the characteristics of flap noise. The major portion of this investigation studied the sound radiated by a realistic large scale model of a triple slotted flap system mounted on a sweptback 6.7 meter semispan model wing. The results of this investigation have identified the major sources of flap generated noise and their dependence of flow defining parameters. In addition, a possible avenue toward the reduction of flap generated noise has been identified via the placement of the flap actuator fairings on the flap system.

  3. 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. PMID:26080179

  4. Oropharyngeal reconstruction with a pedicled submandibular gland flap.

    PubMed

    Mashrah, Mubarak A; Zhou, Shang-Hui; Abdelrehem, Ahmed; Ma, Chunyue; Xu, Liqun; He, Yue; Zhang, Chen-Ping

    2016-05-01

    Locoregional flaps are widely used for reconstruction of small and medium defects in the oral cavity. The submandibular gland flap is a pedicled flap, which derives its blood supply from the facial artery, based on the submandibular gland. We describe the use of the flap in 20 patients who required oropharyngeal reconstruction with a pedicled submandibular gland flap after resection of a tumour between July 2012 and October 2014. Patients with squamous cell carcinoma were excluded. All flaps were pedicled on the facial vessels (inferiorly in 17 patients and superiorly in 3). The indications were: reconstruction of intraoral mucosal defects (n=13), filling the parapharyngeal dead space (n=6), and obliteration of the mastoid (n=1). All the flaps atrophied, but with no clinical effect. One patient developed partial loss of the flap, and one early leakage. There were no cases of xerostomia, and no signs of recurrence during the postoperative follow-up period of 3-26 months. The flap is useful, as it is simple and reliable for reconstruction of small to medium oropharyngeal defects in carefully selected cases, and gives good cosmetic and functional results. PMID:26388070

  5. Skew flap for staged below-knee amputation in sepsis.

    PubMed

    Matthews, Christopher O; Williams, Ian M; Lewis, Peter; McLain, A David; Twine, Christopher P

    2016-04-01

    Skew flap amputation was first described in the 1980s but was never as popular as the long posterior flap amputation. This report describes a staged below-knee amputation in sepsis, with pus throughout the leg and a lack of skin coverage. One benefit of skew flaps never previously published is the fact that the suture line is not directly over the tibia. Therefore, an open wound or incomplete skin coverage is not as important as in long posterior flaps where it often leads to bone exposure and revision amputation. These benefits were utilized in this case leading to stump healing. PMID:26002782

  6. Effects of primary rotor parameters on flapping dynamics

    NASA Technical Reports Server (NTRS)

    Chen, R. T. N.

    1980-01-01

    The effects of flapping dynamics of four main rotor design features that influence the agility, stability, and operational safety of helicopters are studied. The parameters include flapping hinge offset, flapping hinge restraint, pitch-flap coupling, and blade lock number. First, the flapping equations of motion are derived that explicitly contain the design parameters. The dynamic equations are then developed for the tip-path plane, and the influence of individual and combined variations in the design parameters determined. The steady state flapping response is examined with respect to control input and aircraft angular rate which leads to a feedforward control law for control decoupling through cross feed, and a feedback control law to decouple the steady state flapping response. The condition for achieving perfect decoupling of the flapping response due to aircraft pitch and roll rates without using feedback control is also found for the hover case. It is indicated that the frequency of the regressing flapping mode of the rotor system can become low enough to require consideration in the assessment of handling characteristics.

  7. Development of a morphing flap using shape memory alloy actuators: the aerodynamic characteristics of a morphing flap

    NASA Astrophysics Data System (ADS)

    Ko, Seung-Hee; Bae, Jae-Sung; Rho, Jin-Ho

    2014-07-01

    The discontinuous contour of a wing with conventional flaps diminishes the aerodynamic performance of an aircraft. A wing with a continuous contour does not experience extreme flow stream fluctuations during flight, and consequently has good aerodynamic characteristics. In this study, a morphing flap using shape memory alloy actuators is proposed, designed and fabricated, and its aerodynamic characteristics are investigated using aerodynamic analyses and wind tunnel tests. The ribs of the morphing flap are designed and fabricated with multiple elements joined together in a way that allows relative rotations of adjacent elements and forms a smooth contour of the morphing flap. The aerodynamic analyses of this multiple-element morphing-flap wing are performed using XFLR pro; its aerodynamic performance is compared with that of a mechanical-flap wing, and is measured through wind-tunnel tests.

  8. Is there a Rationale for Autologous Breast Reconstruction in Older Patients? A Retrospective Single Center Analysis of Quality of life, Complications and Comorbidities after DIEP or ms-TRAM Flap Using the BREAST-Q.

    PubMed

    Ludolph, Ingo; Horch, Raymund E; Harlander, Marina; Arkudas, Andreas; Bach, Alexander D; Kneser, Ulrich; Schmitz, Marweh; Taeger, Christian D; Beier, Justus P

    2015-01-01

    Autologous breast reconstruction with the deep inferior epigastric perforator (DIEP) or muscle-sparing transverse rectus abdominis myocutaneous (ms-TRAM) flap is a common method in the majority of patients after mastectomy. Because of an increased perioperative risk profile the benefit in older patients is questionable. To assess the postoperative quality of life and peri- and post-operative complications of older compared to younger patients is the aim of this retrospective study. In a retrospective analysis 39 older (i.e. >60 years) and 140 younger patients (i.e. <60 years) with autologous breast reconstruction in the Department of Plastic Surgery at the University Hospital of Erlangen-Nuernberg were surveyed at least 6 month postoperative using the BREAST-Q questionnaire. Correlations were generated between comorbidities and complications. Significant differences were observed regarding hospitalization, pre-existing diseases and the choice of DIEP versus ms-TRAM flaps. Parameters such as major and minor complications, bulging or hernia and risk factors (e.g. smoking or obesity) showed no significant differences. The results of the questionnaire parameters showed no significant difference between both groups, revealing high satisfaction with the aesthetic result and an improvement in quality of life independent of age. Autologous breast reconstruction after mastectomy generates a gain in quality of life and shows a good to excellent overall satisfaction in older as well as younger patients. Despite a longer hospitalization and a different risk profile there were no significant differences regarding minor and major complications in the postoperative course. Hence autologous breast reconstruction for older patients is justified and should be taken into consideration. PMID:26400037

  9. Bipedicled “Superthin” Free Perforator Flaps for Facial Burn Scar Reconstruction: Expanded Scope of Superthin Flaps: A Case Series

    PubMed Central

    Van Anh, Tran; Tien, Nguyen Gia; Hyakusoku, Hiko; Ogawa, Rei

    2015-01-01

    Background: “Superthin flap” is a distinctively thin flap that is thinned primarily to the point that the subdermal vascular network can be seen through a minimal fat layer. Reconstruction of severely disfigured neck and face can be performed using the occipito-cervico-dorsal superthin flap that is harvested from the dorsal region and supercharged by the circumflex scapular vessels. We used bipedicled superthin free perforator flaps to reconstruct scar contractures on half of the face, whole face, or the whole chin-neck area in 17 postburn patients. Methods: This case series report includes all 17 cases. Flaps in the dorsal area were designed. In all cases, one pedicle consisted of the circumflex scapular vessels. In 11, 5, and 1 flaps, the second pedicle consisted of contralateral posterior intercostal perforators (type 1), ipsilateral posterior intercostal perforators (type 2), and ipsilateral circumflex scapular vessels (type 3), respectively. Four patients underwent whole-face reconstruction after acid burn with type 1 or type 3 perforator. The recipient vessels were the superficial temporal vessels and contralateral or ipsilateral facial vessels. Intraoperatively, all adipose tissue in the flap, including between the 2 pedicles, was thinned by scissors before the pedicles were detached from the donor sites. Maximum flap size was 35 × 15 cm. Donor sites were covered by a split full-thickness skin graft. Flap survival and functional and cosmetic results were assessed retrospectively. Results: Fifteen of the 17 flaps survived completely. Two developed partial necrosis due to perforator thrombosis. Some patients developed hypertrophic scars around the flap, but these improved naturally over time. All patients were satisfied with both the cosmetic and functional outcomes of the reconstruction. Conclusion: Bipedicled superthin free perforator flaps may be an excellent choice for reconstruction of severe neck scar contracture. This report expands the scope

  10. Aerodynamic characteristics of wings with cambered external airfoil flaps, including lateral control, with a full-span flap

    NASA Technical Reports Server (NTRS)

    Platt, Robert C

    1936-01-01

    The results of a wind-tunnel investigation of the NACA 23012, the NACA 23021, and the Clark Y airfoils, each equipped with a cambered external-airfoil flap, are presented in this report. The purpose of the research was to determine the relative merit of the various airfoils in combination with the cambered flap and to investigate the use of the flap as a combined lateral-control and high-lift device.

  11. Free combined composite flaps using the lateral circumflex femoral system for repair of massive defects of the head and neck regions: an introduction to the chimeric flap principle.

    PubMed

    Koshima, I; Yamamoto, H; Hosoda, M; Moriguchi, T; Orita, Y; Nagayama, H

    1993-09-01

    Chimeric composite flaps combined using microanastomoses consist of two or more flaps or tissues, each with an isolated pedicle and a single vascular source. Free combined chimeric flaps using the lateral circumflex femoral system were used to treat massive composite defects of the head and neck in 10 cases. A combined anterolateral thigh flap and vascularized iliac bone graft based on the lateral circumflex femoral system and the deep circumflex iliac system was the most commonly used combination. An anteromedial thigh flap and a paraumbilical perforator-based flap were also combined with this principal combination. The advantages of this chimeric flap over other osteocutaneous flaps are: (1) The flap is relatively thin and the pedicle vessels are up to 10 cm longer and are wider than those of other flaps for easier harvesting of the flap. (2) It is unnecessary to reposition the patient. (3) The vascular pedicle to the skin can be separated from that of the bone. (4) The donor site is not close to the recipient site. (5) The donor scar is in an unexposed area. (6) The skin territory of this flap is extremely wide. (7) A combined anterolateral and anteromedial thigh flap and vascularized iliac bone graft can be easily obtained as an extended combined osteocutaneous flap. (8) Other neighboring skin flaps, such as a groin flap, a paraumbilical perforator-based flap, or a medial thigh flap, can be combined with this chimeric flap because several major muscle branches to be anastomosed derive from the lateral circumflex femoral system. Chimeric composite flaps using the lateral circumflex femoral system are considered suitable for the repair of massive composite defects of the head and neck. PMID:8341739

  12. A propeller flap for single-stage nose reconstruction in selected patients: supratrochlear artery axial propeller flap.

    PubMed

    Cordova, Adriana; D'Arpa, Salvatore; Massimiliano, Tripoli; Toia, Francesca; Moschella, Francesco

    2014-06-01

    The paramedian forehead flap is the gold standard technique for nose reconstruction. It requires two different surgical operations which prolonged the postoperative dressing and care. We present our 5-year experience with a propeller flap based on the supratrochlear artery, which allows one-stage transfer of the forehead skin to the nose without the need for pedicle division. This technique is indicated in a selected group of patients who are not suitable for multiple-stage reconstructions because they have concurrent medical conditions, reduced mobility, or live far away from specialized medical centers. We have renamed this procedure as supratrochlear artery axial propeller flap, from the acronym STAAP flap, to stress the axial, well known and constant, vascularization of the flap. In the past 5 years, we have been performing 25 STAAP flaps; full-thickness nasal reconstruction was performed in 11 cases. The patients were 16 males and 9 females, with a mean age of 79.5 years. All patients had multiple comorbidities. Complete flap survival was observed in 23 cases and healing was complete in 7 days. In two cases, there was a partial distal necrosis of the flap treated conservatively. Cosmetic results were good and the patient's satisfaction was significant. These results indicate that the STAAP flap is a reliable and useful technique in selected cases, as old or noncompliant patients who benefit from a one-stage technique of nose reconstruction. PMID:24918712

  13. 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

  14. Effect of wing aspect ratio and flap span on aerodynamic characteristics of an externally blown jet-flap STOL model

    NASA Technical Reports Server (NTRS)

    Smith, C. C., Jr.

    1973-01-01

    An investigation has been conducted to determine the effects of flap span and wing aspect ratio on the static longitudinal aerodynamic characteristics and chordwise and spanwise pressure distributions on the wing and trailing-edge flap of a straight-wing STOL model having an externally blown jet flap without vertical and horizontal tail surfaces. The force tests were made over an angle-of-attack range for several thrust coefficients and two flap deflections. The pressure data are presented as tabulated and plotted chordwise pressure-distribution coefficients for angles of attack of 1 and 16. Pressure-distribution measurements were made at several spanwise stations.

  15. 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.

  16. [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

  17. 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

  18. Quantifying Blood Flow in the DIEP Flap: An Ultrasonographic Study

    PubMed Central

    Pennington, David G.

    2014-01-01

    Background: The maximum weight of tissue that a single perforator can perfuse remains an important question in reconstructive microsurgery. An empirically based equation, known as the flap viability index (FVI), has been established to determine what weight of tissue will survive on one or more perforators. The equation is FVI = Sum d(n)^4/W, where d is the internal diameter of each perforator and W is the final weight of the flap. It has been shown that if FVI exceeds 10, total flap survival is likely, but if under 10, partial flap necrosis is probable. The aim of this study was to measure absolute flow rates in deep inferior epigastric perforator (DIEP) flap pedicles and assess correlation with the determinants of the FVI, perforator diameter and flap weight. Methods: Color Doppler ultrasound was used to quantify arterial flow in 10 consecutive DIEP flap pedicles 24 hours after anastomosis. Results: In single-perforator DIEP flaps, flow rate was highly correlated with perforator diameter (r = 0.82, P = 0.01). Mean arterial flow rate was significantly reduced in DIEP flaps with 2 or more perforators (6 vs 38 cm3/min; P < 0.05). Conclusions: This study confirms that perforator size is a critical factor in optimizing blood flow in perforator-based free tissue transfer. Further research is required to understand the flow dynamics of perforator flaps based on multiple perforators. However, surgeons should be cognizant that a single large perforator may have substantially higher flow rates than multiple small perforators. Routine FVI calculation is recommended to ensure complete flap survival. PMID:25426345

  19. 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.

  20. [Free rectus abdominis muscle perforating artery flaps for reconstruction of the head and neck defects].

    PubMed

    Koshima, I; Handa, T; Satoh, Y; Akisada, K; Orita, Y; Yamamoto, H

    1995-01-01

    During the past eight years, tissue defects of the head and neck region in a total of 45 patients were repaired with free rectus abdominis muscle perforating artery flaps. These flaps are subclassified into (1) reduced musculocutaneous flaps, (2) thin reduced musculocutaneous flaps, (3) paraumbilical perforator-based flaps, and (4) thin paraumbilical perforator-based flaps. The advantages of these flaps are as follows. Since the flaps involve no or only a small portion of the rectus abdominis muscle, (1) the muscle can be left intact on the abdominal wall, and (2) a thin flap can be easily created by simple defatting of the flap. These flaps overcome the major disadvantages of the conventional rectus abdominis musculocutaneous flap, i.e., bulkiness of the flap and frequent postoperative abdominal herniation. The territory of the thin flaps is within 10 cm around the perforator. These flaps are suitable for defects in the head and neck region, because simultaneous flap elevation is possible at the time of tumor resection. Paraumbilical perforator-based flaps are suitable for young females and elderly patients. PMID:7897566

  1. 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.

  2. Active Flap Control of the SMART Rotor for Vibration Reduction

    NASA Technical Reports Server (NTRS)

    Hall, Steven R.; Anand, R. Vaidyanathan; Straub, Friedrich K.; Lau, Benton H.

    2009-01-01

    Active control methodologies were applied to a full-scale active flap rotor obtained during a joint Boeing/ DARPA/NASA/Army test in the Air Force National Full-Scale Aerodynamic Complex 40- by 80-foot anechoic wind tunnel. The active flap rotor is a full-scale MD 900 helicopter main rotor with each of its five blades modified to include an on-blade piezoelectric actuator-driven flap with a span of 18% of radius, 25% of chord, and located at 83% radius. Vibration control demonstrated the potential of active flaps for effective control of vibratory loads, especially normal force loads. Active control of normal force vibratory loads using active flaps and a continuous-time higher harmonic control algorithm was very effective, reducing harmonic (1-5P) normal force vibratory loads by 95% in both cruise and approach conditions. Control of vibratory roll and pitch moments was also demonstrated, although moment control was less effective than normal force control. Finally, active control was used to precisely control blade flap position for correlation with pretest predictions of rotor aeroacoustics. Flap displacements were commanded to follow specific harmonic profiles of 2 deg or more in amplitude, and the flap deflection errors obtained were less than 0.2 deg r.m.s.

  3. 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

  4. Free flap transfer for complex regional pain syndrome type II

    PubMed Central

    Matsuda, Ken; Kikuchi, Mamoru; Murase, Tsuyoshi; Hosokawa, Ko; Shibata, Minoru

    2014-01-01

    Abstract A patient with complex regional pain syndrome type II was successfully treated using free anterolateral thigh flap transfer with digital nerve coaptation to the cutaneous nerve of the flap. Release of the scarred tissue and soft tissue coverage with targeted sensory nerve coaptation were useful in relieving severe pain.

  5. 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)

  6. Perforator propeller flaps for sacral and ischial soft tissue reconstruction

    PubMed Central

    Korambayil, Pradeoth M.; Allalasundaram, KV; Balakrishnan, TM

    2010-01-01

    The perforator-based flaps in the sacral and ischial region is designed according to the localization of perforators that penetrate the gluteus maximus muscle, reach the intra-fascial and supra-fascial planes with the overlying skin forming a rich vascular plexus. The perforator-based flaps described in this article are highly vascularized, have minimal donor site morbidity, and do not require the sacrifice of the gluteus maximus muscle. In a period between April 2008 and March 2009, six patients with sacral pressure sore were reconstructed with propeller flap method based on superior gluteal and parasacral artery perforators. One flap loss was noted. Three cases of ischial pressure sore were reconstructed with longitudinal propeller flap cover, based on inferior gluteal artery perforator. One flap suffered wound infection and dehiscence. Two cases of pilonidal sinus were reconstructed with propeller flap based on parasacral perforators. Both the flaps survived without any complications. Donor sites were closed primarily. In the light of this, they can be considered among the first surgical choices to re-surface soft tissue defects of the sacral and ischial regions. In the series of 11 patients, two patients (18%) suffered complications. PMID:21217972

  7. Development of a free latissimus dorsi muscle flap in cats.

    PubMed

    Nicoll, S A; Fowler, J D; Remedios, A M; Clapson, J B; George, D

    1996-01-01

    Anatomic and experimental evaluation of the feline latissimus dorsi muscle was performed to assess its potential use as a free muscle flap. In the anatomic study, nonselective angiography of the subscapular artery was performed in nine heparinized feline cadavers. The muscle dimensions and vascular anatomy of the dissected latissimus dorsi muscle were recorded. In the experimental study four cats underwent heterotopic transplantation of a partial latissimus dorsi flap, and three cats underwent orthotopic transplantation of a complete latissimus dorsi flap. The mean length and width of the latissimus dorsi muscle was 19.0 and 5.4 cm, respectively. The dominant vascular pedicle was the thoracodorsal artery and vein. The average length and diameter of the thoracodorsal artery was 2.7 cm and 0.6 mm, respectively. Minor vascular pedicles were provided by branches of the intercostal arteries. Numerous choke anastomoses existed between the two pedicle systems. Viability of muscle flaps based on subjective evaluation, angiography, and histopathology, was 66% and 100% in the heterotopic and orthotopic studies, respectively. Flap failure seemed to be caused by both arterial and venous thrombosis. The latissimus dorsi muscle flap met criteria required for application in microvascular reconstruction. The vascular pattern was appropriate and consistent. Donor site morbidity was low, whereas surgical accessibility was high. The muscle satisfied the physical criteria of a free flap. Long-term anastomotic patency and flap viability was shown. PMID:8719085

  8. Monitoring microvascular free flaps with tissue oxygen measurement and PET.

    PubMed

    Schrey, Aleksi R; Kinnunen, Ilpo A J; Grénman, Reidar A; Minn, Heikki R I; Aitasalo, Kalle M J

    2008-07-01

    Tissue oxygen measurement and positron emission tomography (PET) were evaluated as methods for predicting ischemia in microvascular free flaps of the head and neck. Ten patients with head and neck squamous cell cancer underwent resection of the tumour followed by microvascular reconstruction with a free flap. Tissue oxygenation of the flap (P(ti)O(2)) was continuously monitored for three postoperative (POP) days and the blood flow of the flap was assessed using oxygen-15 labelled water and PET. In three free flaps a perfusion problem was suspected due to a remarkable drop in P(ti)O(2)-values, due to two anastomosis problems and due to POP turgor. No flap losses occurred. During the blood flow measurements with PET [mean 8.5 mL 100 g(-1) min(-1 )(SD 2.5)], the mean P(ti)O(2) of the flaps [46.8 mmHg (SD 17.0)] appeared to correlate with each other in each patient (p<0.05, n=10). Tissue oxygenation measurement is a feasible monitoring system of free flaps. The perfusion-study with PET correlates with P(ti)O(2)-measurement. PMID:18231800

  9. Flap advancement coverage after excision of large mucous cysts.

    PubMed

    Shin, Eon K; Jupiter, Jesse B

    2007-06-01

    Mucous cysts are common problems seen by hand surgeons. Surgical excision of symptomatic cysts is the most commonly accepted treatment. Removal of large mucous cysts often requires simultaneous flap coverage or skin grafting for the resulting defect. We present the use of a dorsal advancement flap to permit excellent skin coverage after cyst excision with a tension-free closure. PMID:17549023

  10. Acoustic characteristics of externally blown flap systems with mixer nozzles

    NASA Technical Reports Server (NTRS)

    Goodykoontz, J. H.; Dorsch, R. G.; Wagner, J. M.

    1974-01-01

    Noise tests were conducted on a large scale, cold flow model of an engine-under-the-wing externally blown flap lift augmentation system employing a mixer nozzle. The mixer nozzle was used to reduce the flap impingement velocity and, consequently, try to attenuate the additional noise caused by the interaction between the jet exhaust and the wing flap. Results from the mixer nozzle tests are summarized and compared with the results for a conical nozzle. The comparison showed that with the mixer nozzle, less noise was generated when the trailing flap was in a typical landing setting (e.g., 60 deg). However, for a takeoff flap setting (20 deg), there was little or no difference in the acoustic characteristics when either the mixer or conical nozzle was used.

  11. 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.

  12. Propeller Flaps: A Review of Indications, Technique, and Results

    PubMed Central

    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. PMID:24971367

  13. Simultaneous Extended ALT Flaps for Foot Salvage After Severe Frostbite.

    PubMed

    Fodor, Marius; Bota, Olimpiu; Fodor, Lucian

    2016-01-01

    Plantar area reconstruction represents the most challenging part of the lower limb. The anterolateral thigh (ALT) flap proved to be a versatile flap for this special area. Herein, we present the application of bilateral ALT free flaps for foot salvage after frostbite injury and long-term follow-up. Single perforator bilateral ALT flaps (304 and 320 cm) were harvested and anastomosed to posterior tibial vessels. The lateral femoral cutaneous nerve was anastomosed to the calcaneal branches of the posterior tibial nerve. The two-point discrimination test showed values from 16 to 28 mm in different flap areas 5 years later. The patient is able to walk with crutches. This is the first case report of bilateral ALT for foot salvage. PMID:26284647

  14. Works on theory of flapping wing. [considering boundary layer

    NASA Technical Reports Server (NTRS)

    Golubev, V. V.

    1980-01-01

    It is shown mathematically that taking account of the boundary layer is the only way to develop a theory of flapping wings without violating the basic observations and mathematics of hydromechanics. A theory of thrust generation by flapping wings can be developed if the conventional downstream velocity discontinuity surface is replaced with the observed Karman type vortex streets behind a flapping wing. Experiments show that the direction of such vortices is the reverse of that of conventional Karman streets. The streets form by breakdown of the boundary layer. Detailed analysis of the movements of certain birds and insects during flight 'in place' is fully consistent with this theory of the lift, thrust and drag of flapping wings. Further directions for research into flight with flapping wings are indicated.

  15. 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.

  16. Multi-staged flap reconstruction for complex radiation thoracic ulcer

    PubMed Central

    Valença-Filipe, Rita; Horta, Ricardo; Costa, Joana; Carvalho, Jorge; Martins, Apolino; Silva, Álvaro

    2014-01-01

    INTRODUCTION Chest wall reconstruction due to previous radiation therapy can be challenging and complex, requiring a multidisciplinary approach. PRESENTATION OF CASE The authors present the case of a 84-year-old woman with a right chest wall radionecrosis ulcer, that was submitted to an ablative surgery resulting in a full-thickness defect of 224 cm2, firstly reconstructed with a pedicled omental flap. Due to partial flap necrosis, other debridements and chest wall multi-staged flap reconstruction were performed. DISCUSSION This case highlights that the reconstructive choice should be individualized and dependent on patient and local factors. The authors advise that surgical team should work closely and be well versed in chest wall reconstruction with a variety of pedicled flaps, when a complication occurs. CONCLUSION A multi-staged flap reconstruction could be a salvage procedure for the coverage of complex, great and complicated chest wall defects due to previous radiation therapy. PMID:25437678

  17. Preservation of Hand Function Using Muscle Perforator Flaps

    PubMed Central

    2008-01-01

    Adequate soft tissue coverage is imperative after any interventions performed to maximize or preserve hand function. Although this can most simply be achieved by primary closure or a skin graft if possible, often a vascularized flap will be preferable, especially if a later secondary procedure is planned. Even moderately sized skin deficits of the upper extremity, and especially if involving the hand itself, can be better covered using a free tissue transfer. Many reasonable options in this regard are available. Muscle perforator flaps, as a relatively new variant of a fasciocutaneous flap, have unique attributes, including availability, diversity, accessibility, large size, and lengthy vascular pedicle, and since no muscle need be included, donor site function is preserved. As is shown here in a series of nine muscle perforator flaps in eight patients, these represent yet another alternative that should be considered if selection of a free flap is indicated to maintain hand function. PMID:18780005

  18. Distally Based Abductor Hallucis Adipomuscular Flap for Forefoot Plantar Reconstruction.

    PubMed

    Lee, Sanglim; Kim, Min Bom; Lee, Young Ho; Baek, Jeong Kook; Baek, Goo Hyun

    2015-09-01

    Soft tissue and bone defects of the lower leg, ankle, and heel region often require coverage by local or distant flaps. The authors successfully used the distally based adipomuscular abductor hallucis flap for the treatment of 7 patients with soft tissue defect on the plantar forefoot after diabetic ulcer (n = 2), excision of melanoma at the medial forefoot (n = 3), and posttraumatic defects of the plantar forefoot (n = 2). The size of the defects ranged from 6 to 36 cm. All defects were covered successfully without major complications. The distally based adipomuscular flap from the abductor hallucis muscle provides a reliable coverage for small and moderate defects of the plantar and medial forefoot. This flap is often preferable to the use of free flaps because the surgery is rapidly performed and does not require microsurgical expertise. PMID:25565013

  19. 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.

  20. 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.

  1. Tensor fascia lata flap versus tensor fascia lata perforator-based island flap for the coverage of extensive trochanteric pressure sores.

    PubMed

    Kim, Youn Hwan; Kim, Sang Wha; Kim, Jeong Tae; Kim, Chang Yeon

    2013-06-01

    Tensor fascia lata (TFL) musculocutaneous flaps often require a donor site graft when harvesting a large flap. However, a major drawback is that it also sacrifices the muscle. To overcome this disadvantage, we designed a TFL perforator-based island flap that was harvested from a site near the defect and involved transposition within 90 degrees without full isolation of the pedicles. We performed procedures on 17 musculocutaneous flaps and 23 perforator-based island flaps, and compared the outcomes of these surgeries. The overall complication rate was 27.5% (11 regions). There were 7 complications related to the musculocutaneous flaps and 4 complications related to the perforator flaps. Although there were no statistical differences between those groups, lower complication rates were associated with procedures involving perforator flaps. The TFL perforator procedure is a simple and fast operation that avoids sacrificing muscle. This decreases complication rates compared to true perforator flap techniques that require dissection around the perforator or pedicle. PMID:23392259

  2. Superior gluteal artery perforator flap in bilateral breast reconstruction.

    PubMed

    Werdin, Frank; Peek, Alberto; Martin, Nicolas C S; Baumeister, Steffen

    2010-01-01

    The incidence of bilateral breast reconstruction is increasing particularly due to genetic counseling and the option for bilateral prophylactic mastectomies. The decision to undergo a prophylactic mastectomy depends on the achievable outcomes of breast reconstruction. The free superior gluteal artery perforator flap (sGAP) flap is one option for autologous bilateral reconstruction which has rarely been reported.All bilateral sGAP flaps performed in the department of plastic surgery at the Behandlungszentrum Vogtareuth over a period of 4.5 years were retrospectively analyzed for indication, success rate, and complications.Thirty sGAP flaps were performed for bilateral breast reconstruction. The average age of the 15 women was 42 years and the average body mass index was 20.8. Indications for breast reconstruction were predominantly prophylactic mastectomies (60%). Indication for a sGAP flap was either a thin patient with insufficient abdominal tissue or a 2-staged bilateral reconstruction. 83% of the breast reconstructions were performed secondarily and 93% in 2 stages. The average operating time was 7 hours 12 minutes. Twenty-nine flaps (97%) were successful. Complications were fat necrosis (n = 3), hematoma (n = 3), and breast seroma (n = 1). Donor site complications were seroma (n = 8), infection (n = 1), and wound dehiscence (n = 1).Our results with bilateral breast reconstruction with the sGAP flap show cosmetically appealing results with high success and low complication rates on the breast. However, seromas on the donor site occurred in 27%. In addition, the sGAP flap is a technically demanding and time consuming operation. We recommend the sGAP flap when the abdomen has not enough tissue bulk to perform a deep inferior epigastric perforator flap or for a 2-staged bilateral reconstruction. This is often the case in women with a hereditary high risk of breast cancer who often present as young and slim patients. PMID:20010408

  3. Intravascular heparin protects muscle flaps from ischemia/reperfusion injury.

    PubMed

    Li, X; Cooley, B C; Fowler, J D; Gould, J S

    1995-01-01

    Heparin has been found to decrease ischemia/reperfusion injury in skeletal muscle and other tissue/organ systems. The timing of heparin administration to the muscle vasculature has not been explored. We investigated the use of heparinized blood as a washout solution during ischemia to reduce ischemia/reperfusion injury. A rat cutaneous maximus muscle free flap was subjected to a 10-hr period of room temperature ischemia, then was heterotopically transplanted to the groin via microsurgical revascularization to the femoral vessels. In three experimental groups, flaps were subjected to brief ex vivo perfusion with autologous heparinized blood, at 2, 5, or 8 hr into the 10-hr ischemic interval. In the two other groups, the flaps were not perfused, and the animals were systemically heparinized either before ischemia or before transplantation, respectively. A control group underwent no flap perfusion or systemic heparinization. After transplantation, flaps were given a 48-hr period of in vivo reperfusion, then were harvested for evaluation. Flaps undergoing ex vivo perfusion or preischemic heparinization had no significant differences in weight gain (edema) compared with flaps receiving posttransplant heparinization or no heparinization (controls). The dehydrogenase staining of muscle biopsies was significantly faster (indicative of viable tissue) for perfused flaps and the flaps for which the animals received preischemic heparinization, when compared with flaps for which the animals received posttransplant heparinization or no heparinization. From these results, we conclude that heparin offers protection from ischemia/reperfusion injury when it can be introduced into the vascular network either prior to or during the ischemia period. These findings suggest the possibility of using heparinized washout solutions to enhance survival in amputated extremities. PMID:7783611

  4. Reconstructive Surgery for Severe Penile Inadequacy: Phalloplasty with a Free Radial Forearm Flap or a Pedicled Anterolateral Thigh Flap

    PubMed Central

    Lumen, N.; Monstrey, S.; Ceulemans, P.; van Laecke, E.; Hoebeke, P.

    2008-01-01

    Objectives. Severe penile inadequacy in adolescents is rare. Phallic reconstruction to treat this devastating condition is a major challenge to the reconstructive surgeon. Phallic reconstruction using the free radial forearm flap (RFF) or the pedicled anterolateral thigh flap (ALTF) has been routinely used in female-to-male transsexuals. Recently we started to use these techniques in the treatment of severe penile inadequacy. Methods. Eleven males (age 15 to 42 years) were treated with a phallic reconstruction. The RFF is our method of choice; the ALTF is an alternative when a free flap is contraindicated or less desired by the patient. The RFF was used in 7 patients, the ALTF in 4 patients. Mean followup was 25 months (range: 4–49 months). Aesthetic and functional results were evaluated. Results. There were no complications related to the flap. Aesthetic results were judged as “good” in 9 patients and “moderate” in 2 patients. Sensitivity in the RFF was superior compared to the ALTF. Four patients developed urinary complications (stricture and/or fistula). Six patients underwent erectile implant surgery. In 2 patients the erectile implant had to be removed due to infection or erosion. Conclusion. In case of severe penile inadequacy due to whatever condition, a phalloplasty is the preferred treatment nowadays. The free radial forearm flap is still the method of choice. The anterolateral thigh flap can be a good alternative, especially when free flaps are contraindicated, but sensitivity is markedly inferior in these flaps. PMID:19009034

  5. 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.

  6. 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

  7. Expanded retroauricular skin and fascial flap in congenital microtia reconstruction.

    PubMed

    Zhang, Qingguo; Quan, Yuzhu; Su, Yuanda; Shi, Lei; Xie, Yangchun; Liu, Xinhai

    2010-04-01

    The aim of this article is to report the application of expanding retroauricular skin fascia flap, and autogenous costal cartilage for congenital microtia reconstruction. Microtia reconstruction was generally completed in 3 surgical stages. In the first surgical stage, a 50 or 80 mL kidney-shaped tissue expander was inserted subcutaneously in the retroauricular mastoid region. Inflation of saline volume increased up to 60 to 80 mL, and skin flap was expanded for 2 to 3 months postoperatively. In the second surgical stage, removal of tissue expander, formation of retroauricular skin flap, elevation of retroauricular fascia flap, and pedicles of both flaps in remnant ear side were performed. Costal cartilage was harvested from ipsilateral side chest to the ear for reconstruction. The 3D ear framework was sculpted with stabilization of structure, contour and erection. Simultaneously, intermediate full thickness skin graft of 4 x 8 cm was obtained from previous incision site from where costal cartilage was harvested. Cartilage ear framework was anchored between skin flap and fascia flap, and fixed it symmetrically to the opposite normal ear, inferior portion of the ear framework was wrapped by remnant ear lobule, expanded skin flap covered the anterior portion of the framework, fascial flap was draped to the posterior side of framework and helical rim, then fascial flap was surfaced by intermediate full thickness skin graft. Suction drain was inserted and coated between skin flap and framework, drain was removed fifth postoperative day. Tragus construction and conchal excavation with skin graft was performed in the third stage of microtia reconstruction. Between October 2000 and October 2007, 426 cases were diagnosed as unilateral microtia patients and 22 cases were bilateral microtia patients. Therefore, 448 microtia ears were treated with tissue expander and autogenous costal cartilage. In 262 cases, structure of the helix, tragus, conchal excavation

  8. 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.

  9. Flapping propulsion with tip pitch control

    NASA Astrophysics Data System (ADS)

    Huera-Huarte, Francisco; Gharib, Morteza

    2014-11-01

    The effect of flexibility in the propulsion performance and efficiency of oscillating pitching foils has received a large amount of attention in the past years. Scientists have used simplified robotic models that mimic the kinematics of flying and swimming animals, in order to get inspiration to build more efficient engineering systems. Compliance is one of the aspects that has received more attention, as it seems to be a common feature in nature's flyers and swimmers. Active or passive control elements are also common in nature. We will show how thrust generation in a pitching fin, can be greatly affected by controlling the tip pitch motion dynamically and independently of the fin itself. This is in fact a controlled local change of curvature of the end of the fin. A robotic system has been designed in a way that not only flapping amplitudes and frequencies can be controlled, but also the amplitudes and frequencies of the tip and the phase difference between the tip and the fin. We measured thrust forces and the vortex dynamics in the near wake of the system, by using planar DPIV (Digital Particle Image Velocimetry) in a wide variety of flapping situations with tip control. Funding from Spanish Ministry of Science through Grant DPI2012-37904 is gratefully acknowledged.

  10. 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.

  11. Design and construction of pre-stressed piezoelectric unimorph for trailing edge flap actuation

    NASA Astrophysics Data System (ADS)

    Kang, Lae-Hyong; Lee, Jong-Won; Han, Jae-Hung

    2009-07-01

    This paper presents a trailing edge flap actuation mechanism using a novel pre-stressed piezoelectric unimorph, PUMPS (Piezoelectric Unimorph with Mechanically Pre-stressed Substrate). Experimental evaluation of actuation performance such as force-displacement characteristics of PUMPS actuators showed that the performance of PUMPS satisfied the requirements for trailing edge flap actuation. Subsequently, flap actuation mechanisms were designed and constructed with several slot types in the flaps, and stacked PUMPS actuators were applied to the flap actuation mechanisms. Experimental study of the test wing models with four flaps was accomplished, and the flap angle was achieved up to +/-5.5° within 15Hz under maximum applicable voltage.

  12. Temporal muscle flap in reconstruction of maxillo-facial tissues

    PubMed Central

    Krzymański, Grzegorz; Dąbrowski, Jarosław; Przybysz, Jan; Domański, Wojciech; Biernacka, Barbara

    2012-01-01

    Aim of the study Presents our experience in reconstruction of postsurgical defects with use of temporal muscle flap. Material and methods In the years 1996–2010 we treated 10 patients with malignant neoplasms of maxillo-facial region. Following tumor removal the fascia-muscle flaps of temporal muscle were used for reconstruction. Temporal muscle flaps were applied in 5 cases for reconstructing the defect of eye socket tissue after extensive resections and in the other 5 patients was used for reconstructing the defect of palate following maxillary resections. Results All the flaps of temporal muscle that were used for reconstructing eye sockets incorporated with no local reaction. In one case of flap applied into the oral cavity for tightly separate from nasal, partial necrosis of flap's edge and oro-nasal fistula occurred. Conclusions Fascia-muscular flap of temporal muscle is a simple, easy and effective method of tissue reconstruction in maxillo-facial region following extensive oncologic procedures. PMID:23788888

  13. Lower extremity muscle perforator flaps for lower extremity reconstruction.

    PubMed

    Hallock, Geoffrey G

    2004-10-01

    A true muscle perforator flap is distinguished by the requisite intramuscular dissection of its musculocutaneous perforator to capture the same musculocutaneous territory but with total exclusion of the muscle, and thereby results in minimal functional impairment. Adhering to this definition, several lower extremity donor sites now are available, each with specific attributes especially useful for consideration in the treatment of lower extremity defects. In this author's experience over the past two decades, 20 lower extremity muscle perforator flaps using multiple donor sites proved advantageous for lower extremity coverage problems as either a local pedicled flap or as a microsurgical tissue transfer. Significant complications occurred in 30 percent of flaps (six of 20) in that further intervention was required. Venous insufficiency and bulkiness were found to be the major inherent shortcomings. However, giant flaps, lengthy and large-caliber vascular pedicles, and the possibility for combined flaps were important assets. The choice of a lower extremity muscle perforator flap for lower extremity reconstruction limited the surgical intervention and morbidity to a single body region. PMID:15457022

  14. 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. PMID:20110799

  15. 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

  16. Comparison of calculated and measured helicopter rotor lateral flapping angles

    NASA Technical Reports Server (NTRS)

    Johnson, W.

    1980-01-01

    Calculated and measured values of helicopter rotor flapping angles in forward flight are compared for a model rotor in a wind tunnel and an autogiro in gliding flight. The lateral flapping angles can be accurately predicted when a calculation of the nonuniform wake-induced velocity is used. At low advance ratios, it is also necessary to use a free wake geometry calculation. For the cases considered, the tip vortices in the rotor wake remain very close to the tip-path plane, so the calculated values of the flapping motion are sensitive to the fine details of the wake structure, specifically the viscous core radius of the tip vortices.

  17. 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

  18. 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.

  19. 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.

  20. Osteoradionecrosis of the olecranon: treatment by radial forearm flap

    SciTech Connect

    Thornton, J.W.; Stevenson, T.R.; VanderKolk, C.A.

    1987-12-01

    Osteoradionecrosis of the olecranon is an unusual pathologic entity, treated best by debridement and wound closure using vascularized tissue. Local skin is often unavailable for flap design and transposition. The radial forearm flap can be isolated on a proximal vascular pedicle and transposed to cover the wound. In the case presented, healing was brisk and complete, allowing early elbow mobilization. Although the donor site is not easily concealed, no functional impairment results from flap elevation and all full-thickness wounds are confined to the involved extremity.

  1. Upper lip reconstruction with a radial forearm free flap.

    PubMed

    Mandrekas, A D; Page, R; O'Neill, T J

    1994-05-01

    Although there are several methods available for lip reconstruction, the challenge for plastic surgeons is young children, in whom there is no laxity of skin. Free-tissue transfer is the method of choice in young children to avoid large unsightly scars and severe distortion of facial appearance. The radial forearm free flap is an ideal flap for lip reconstruction because it is thin and can be folded to restore both the skin and the inner lining. We present reconstruction of half the upper lip in a young girl, in whom the radial forearm free flap was folded to replace the full-thickness defect. PMID:7918852

  2. Computed Tomography Angiography for Preoperative Thoracoabdominal Flap Planning.

    PubMed

    O'Malley, Ryan B; Robinson, Tracy J; Kozlow, Jeffrey H; Liu, Peter S

    2016-01-01

    Mastectomy rates have increased, coinciding with more advanced reconstruction options. Deep inferior epigastric perforator (DIEP) flaps decrease abdominal donor site morbidity, but require considerable technical expertise. Preoperative computed tomography angiography (CTA) can accurately demonstrate DIEA anatomy and perforator courses, facilitating preoperative planning and flap design, allowing for more targeted intraoperative microdissection. Patients who undergo CTA before DIEP flap have better clinical outcomes with shorter operative times and hospital length of stay, which can decrease overall associated health care costs. Future directions include selected imaging of the thoracic anatomy and recipient vasculature, allowing for additional preoperative planning and customization. PMID:26654396

  3. 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. PMID:24785755

  4. Comparison of Modified Limberg Flap and Karydakis Flap Operations in Pilonidal Sinus Surgery: Prospective Randomized Study

    PubMed Central

    Tokac, Mehmet; Dumlu, Ersin Gurkan; Aydin, Murat Seyit; Yalcın, Abdussamed; Kilic, Mehmet

    2015-01-01

    The best surgical technique for pilonidal sinus disease (PSD) is still disputed. The objective of this prospective randomized study is to compare the short and long-term results of modified Limberg flap and Karydakis flap surgeries that have been widely used in recent years. Ninety one patients were included in the study. The patients were divided into two groups: modified Limberg flap (MLF; n = 46) and Karydakis flap (KF; n = 45). Preoperative findings of the patients, their surgical findings, and short and long-term postoperative findings were recorded and statistically compared. While no significant difference was discovered between the groups in terms of postoperative analgesic need, hospital stay, postoperative infection rate, drain stay time, painless sitting time, painless toilet-sitting time, and painless walking time, return to work or school time was shorter in the MLF group compared with the KF group (20.61 ± 7.89 days, 23.29 ± 6.42, respectively; P < 0.05). Cosmetically, the visual analog scale (VAS) of the KF group was significantly higher than that of the MLF group (VAS score 7.12 ± 1.28, 5.45 ± 1.77, respectively; P < 0.05). Considering recurrence rates, no statistically significant difference was found between the groups. Our study found out that short and long-term results of the MLF and KF procedures are similar. We believe both methods can be safely used in surgical PSD treatment given that in the MLF procedure, shorter return-to-work time is achieved, while the procedure provides better cosmetic results. PMID:26011208

  5. Facial Artery Musculomucosal (FAMM) flap for nasal lining in reconstruction of large full thickness lateral nasal defects

    PubMed Central

    Rahpeyma, Amin; Khajehahmadi, Saeedeh

    2015-01-01

    Obviously, restoring the nasal lining is a great challenge in the reconstruction of nasal defects. Full thickness nasal defects usually require special flaps for reconstructing the nasal lining. Intranasal mucosal flaps, hinge over flaps, perinasal second flaps, folded or second forehead flaps and finally free flaps are examples that can be used for this purpose. Moreover, the case presented in this article expresses a new role for the superiorly based Facial Artery Musculomucosal (FAMM) flap in this topic. Furthermore, mucosal island variant of this flap is presented to reduce the tension on this flap while restoring the nasal lining in large full thickness nasal defect. PMID:26566439

  6. 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

  7. 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.

  8. Computational Investigation of Flap-Edges

    NASA Technical Reports Server (NTRS)

    Cummings, Russell M.

    1997-01-01

    The current study expands the application of computational fluid dynamics to three-dimensional multi-element high-lift systems by investigating the flow dynamics created by a slat edge. Flow is computed over a three-element high-lift configuration using an incompressible Navier-Stokes solver with structured, overset grids processed assuming full turbulence with the one-equation Baldwin-Barth turbulence model. The geometry consists of an unswept wing, which spans the wind tunnel test section, a single element half-span Fowler flap, and a three-quarter span slat. Results are presented for the wing configured for landing with a chord based Reynolds number of 3.7 million. Results for the three-quarter span slat case are compared to the full-span slat and two-dimensional investigations.

  9. 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

  10. 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.

  11. The Vascularized Medial Femoral Corticoperiosteal Flap for Thumb Reconstruction

    PubMed Central

    Amin, Kavit; Darhouse, Nagham; Sivakumar, Bran; Floyd, David

    2015-01-01

    Summary: We present an interesting method of shaping a vascularized medial femoral condyle (MFC) flap into a “neophalanx” for phalangeal reconstruction. Our patient presented with limited strength and function secondary to fracture nonunion of the proximal phalanx of the dominant thumb. Following excision of the pseudarthrosis, an MFC corticoperiosteal flap was harvested, sculpted into a prism shape and inset. The superomedial genicular pedicle was anastomosed to the princeps pollicis artery and a cephalic tributary. On follow-up, new bone growth was seen on radiographs and the patient had substantially improved function, with full metacarpophalangeal extension, a Kapandji score of 9, and a markedly reduced Disabilities of the Arm, Shoulder and Hand score of 2.68. The MFC flap is useful for reconstruction of bony defects, with minimal donor morbidity. This versatile vascularized flap can be crafted to requisite shapes and is useful for small defects in the hand, including phalangeal reconstruction. PMID:26495205

  12. 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.

  13. 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.

  14. 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

  15. 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...

  16. Free posterior tibial flap reconstruction for hypopharyngeal squamous cell carcinoma

    PubMed Central

    2014-01-01

    Objectives The aim of this article was to determine outcomes in patients with squamous cell carcinoma of the hypopharynx (SCCHP) in whom the free posterior tibial flap was used for primary reconstruction of hypopharynx defects after cancer resection. Subjects and methods Between August 2009 and February 2012, 10 patients with SCCHP underwent posterior tibial flap reconstruction for hypopharynx defects. The corresponding clinical data were retrospectively collected and analyzed. Results Despite the multistep and time-consuming procedure, the posterior tibial flap survival rate was 100%. Operation-induced complications did not occur in four patients. Six patients developed postoperative hypoproteinemia, four patients developed postoperative pulmonary infections, and four patients developed pharyngeal fistula. The pharyngeal and laryngeal functions of all patients were preserved. Conclusion Our experience demonstrates that the posterior tibial flap is a safe and reliable choice for the reconstruction of hypopharynx defects. PMID:24884631

  17. 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.

  18. Breast reconstruction with the fasciocutaneous infragluteal free flap (FCI).

    PubMed

    Papp, Christoph; Windhofer, Christian; Gruber, Sabine

    2007-02-01

    Thin patients who will not accept breast reconstruction with foreign material may not have enough tissue associated with the TRAM or latissimus muscle to achieve an acceptable reconstruction. We feel the next choice is tissue from the infragluteal region raised and moved as a free fasciocutaneous flap (FCI) based on the descending branch of the inferior gluteal artery. This (FCI) has not been described for this to our knowledge. Thirty-five FCI flaps were done for 28 patients between 1998 and 2005 for autologous breast reconstruction, as well as simultaneous augmentation of the contralateral breast in 4 of these patients. There was no flap loss. Complications include seroma, scar pain, and fat necrosis and are reported and discussed. We suggest that the FCI flap be considered as a worthy alternative for autologous breast reconstruction in thin patients. PMID:17245137

  19. Free microvascular transplantation of the trapezius musculocutaneous flap in dogs.

    PubMed

    Philibert, D; Fowler, J D; Clapson, J B

    1992-01-01

    A musculocutaneous flap based on the prescapular branch of the superficial cervical artery and including the cervical part of the trapezius muscle and overlying skin was transplanted over a defect created on the medial side of the contralateral tibia in four dogs by using microvascular technique. The donor and recipient sites in three dogs were examined clinically for 21 days, after which they were examined angiographically and histologically. All dogs were free of lameness by hour 48. Seromas formed at the donor site between days 7 and 15. One vascular pedicle was traumatized at hour 40, and the dog was euthanatized. Three flaps survived with minimal necrosis. Edema of the flaps was severe from days 5 to 11. Angiograms showed complete perfusion of the flaps, and survival was confirmed histologically. Esthetic appearance and function were good in one dog at month 7. PMID:1455645

  20. 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.

  1. 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.

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

    PubMed Central

    Woo, Seung Hoon

    2016-01-01

    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. PMID:26976033

  3. Numerical simulation of self-propulsion of flapping flexible plates

    NASA Astrophysics Data System (ADS)

    Lu, Xi-Yun; Hua, Ru-Nan; Fluid Mechanics Team

    2012-11-01

    Self-propulsion of flapping flexible plates has been studied numerically by means of an immersed boundary-lattice Boltzmann method for the fluid dynamics around the plate and a finite element method for the deformable flapping motion of the plate. Both the two- and three-dimensional flexible plates are investigated to reveal the propulsion properties and their differences. As a result of the fluid-plate interaction, three typical movement regimes have been identified and can be briefly described as forward, backward, and irregular movements which mainly depend on the flapping amplitude and bending rigidity. It is found that there exists an optimal range of the bending rigidity for large propulsive speed or high efficiency in the forward movement regime, consistent with the observation and measurement of swimming and flying animals. The results obtained in this study provide physical insights into understanding of the propulsive mechanisms of the flapping fin or wing of animals.

  4. 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

  5. Computer study of a jet flap ASTVOL 'Harrier'

    NASA Technical Reports Server (NTRS)

    Wilson, S. B., III; Liperra, L. D.

    1984-01-01

    A study of the costs/benefits trade-off was conducted for an Advanced Supersonic Short Takeoff and Vertical Landing (ASTOVL) aircraft incorporating a jet flap. The data used were the theory of jet flaps and high aspect ratio nozzles, experience with a V/STOL aircraft study performed for NASA Ames Research Center in February 1982, and a high performance aircraft-synthesis program (ACSYNT). The methodology was to accurately model the supersonic Harrier V/STOL aircraft design on ACSYNT, and then modify the design by both adding high aspect-ratio nozzles in place of the rear (core-flow) nozzles on the Pegasus-type turbofan engine, and integrating these nozzles on each wing's trailing edge, thus creating a jet flap. The predicted performance advantages (increase in maximum lift coefficient with flap deflection and horizontal thrust recovery) were traded off against the disadvantages (additional weight and thrust loss due to ducting) on two representative missions.

  6. Wind Tunnel Test of the SMART Active Flap Rotor

    NASA Technical Reports Server (NTRS)

    Straub, Friedrich K.; Anand, Vaidyanthan R.; Birchette, Terrence S.; Lau, Benton H.

    2009-01-01

    Boeing and a team from Air Force, NASA, Army, DARPA, MIT, UCLA, and U. of Maryland have successfully completed a wind-tunnel test of the smart material actuated rotor technology (SMART) rotor in the 40- by 80-foot wind-tunnel of the National Full-Scale Aerodynamic Complex at NASA Ames Research Center. The Boeing SMART rotor is a full-scale, five-bladed bearingless MD 900 helicopter rotor modified with a piezoelectric-actuated trailing edge flap on each blade. The eleven-week test program evaluated the forward flight characteristics of the active-flap rotor at speeds up to 155 knots, gathered data to validate state-of-the-art codes for rotor aero-acoustic analysis, and quantified the effects of open and closed loop active flap control on rotor loads, noise, and performance. The test demonstrated on-blade smart material control of flaps on a full-scale rotor for the first time in a wind tunnel. The effectiveness of the active flap control on noise and vibration was conclusively demonstrated. Results showed significant reductions up to 6dB in blade-vortex-interaction and in-plane noise, as well as reductions in vibratory hub loads up to 80%. Trailing-edge flap deflections were controlled within 0.1 degrees of the commanded value. The impact of the active flap on control power, rotor smoothing, and performance was also demonstrated. Finally, the reliability of the flap actuation system was successfully proven in more than 60 hours of wind-tunnel testing.

  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. Versatility of the hatchet flap in facial reconstruction.

    PubMed

    Gargano, F; Alfano, C

    2005-01-01

    The hatchet flap, well known for repair of the nasal pyramid, laterofacial defects and pressure sores, is used to reconstruct different aesthetic units of the face. The authors describe the surgical technique and its clinical applications to the different face subunits in 38 patients, highlighting the easy learning curve, the versatility of the flap and the good aesthetic results when the principles of the facial units are respected. No previous detailed report has been described in the literature. PMID:16173514

  9. 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.

  10. The innervated free toe web flap for clitoris reconstruction.

    PubMed

    Dabernig, Jörg; Shelley, Odhran P; Schaff, Jürgen

    2007-01-01

    Clitoris reconstruction is often used in transgender reassignment. Most techniques now reconstruct the clitoris using glans pedicled on the dorsal phallic neurovascular bundle. Other techniques of clitoris reconstruction re-shape retained elements of the proximal segment of the corpora cavernosa, as well as techniques mobilising local flaps. We are presenting a new technique for clitoris reconstruction using an innervated free web space flap. The operative technique and outcome are illustrated and discussed in this case report. PMID:17368123

  11. 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.

  12. The lateral calcaneal flap for sensate heel reconstruction revisited.

    PubMed

    Korentager, R

    1994-06-01

    Defects of the heel can be difficult to treat because they require a thin, sensate, soft-tissue cover. The lateral calcaneal flap can provide this type of reconstruction in selected patients. A 27-year-old man had a painful defect in a grafted heel that prevented him from working. A satisfactory painless heel was provided by resurfacing the area with a lateral calcaneal flap. The donor defect was minimized by interfascicular dissection of the sural nerve. PMID:8199942

  13. Phase II simulation evaluation of the flying qualities of two tilt-wing flap control concepts

    NASA Technical Reports Server (NTRS)

    Birckelbaw, Lourdes G.; Corliss, Lloyd D.

    1992-01-01

    A simulation study was initiated to investigate alternative wing and flap controls for tilt-wing aircraft. 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, reported in this paper, introduced an alternate method for pilot control of the geared flap and further studied the flying qualities of the programmed flap, and two geared flap configurations. The results showed little difference among the three flap control configurations except during a longitudinal reposition task where the programmed flap configuration was the best. The addition of pitch attitude stabilization greatly enhanced the aircraft handling qualities. This paper describes the tilt-wing aircraft and the flap control concepts, and presents the results of the second simulation experiment.

  14. 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.

  15. The distally based superficial sural flap for reconstruction of the lower leg and foot.

    PubMed

    Rajacic, N; Darweesh, M; Jayakrishnan, K; Gang, R K; Jojic, S

    1996-09-01

    We describe our experience with the use of distally based superficial sural flaps for coverage of defects in the lower leg and foot in 21 patients. In 18 patients the flap was successfully transferred, in 2 cases partial necrosis of the flap occurred and 1 flap failed completely. In 18 cases the flap was used as a fasciocutaneous flap and in 3 cases as a fascial flap only. The advantages of this flap are: easy and quick dissection, hence saving operating time, minimal morbidity of donor site and preservation of major arteries of the leg. Although the flap was described as reliable for covering defects around the ankle joint, we have been able to cover defects of the dorsum of the foot distally and up to the mid-third of the tibia proximally. PMID:8881785

  16. Pressure distribution over NACA 23012 airfoil with a slotted and a split flap

    NASA Technical Reports Server (NTRS)

    Harris, Thomas A; Lowry, John G

    1941-01-01

    A pressure-distribution investigation has been conducted in the NACA 4 by 6-foot vertical wind tunnel to determine the air loads on an NACA 23012 airfoil in combination with a 25.66-percent-chord slotted flap and a 20-percent-chord split flap. Pressures were measured on both the upper and the lower surfaces of the main airfoil and the flaps for several angles of attack and at several flap settings. The data, presented as pressure diagrams and as graphs of the section coefficients for the flap alone and for the airfoil-flap combinations, are applicable to rib and flap design for a combination of a thick airfoil and a slotted or a split flap. The results of previous tests of a NACA 23012 airfoil with a slotted flap are compared with the present results.

  17. 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

  18. Surgical anatomy and utility of pedicled vascularized tissue flaps for multilayered repair of skull base defects.

    PubMed

    Safavi-Abbasi, Sam; Komune, Noritaka; Archer, Jacob B; Sun, Hai; Theodore, Nicholas; James, Jeffrey; Little, Andrew S; Nakaji, Peter; Sughrue, Michael E; Rhoton, Albert L; Spetzler, Robert F

    2016-08-01

    OBJECT The objective of this study was to describe the surgical anatomy and technical nuances of various vascularized tissue flaps. METHODS The surgical anatomy of various tissue flaps and their vascular pedicles was studied in 5 colored silicone-injected anatomical specimens. Medical records were reviewed of 11 consecutive patients who underwent repair of extensive skull base defects with a combination of various vascularized flaps. RESULTS The supraorbital, supratrochlear, superficial temporal, greater auricular, and occipital arteries contribute to the vascular supply of the pericranium. The pericranial flap can be designed based on an axial blood supply. Laterally, various flaps are supplied by the deep or superficial temporal arteries. The nasoseptal flap is a vascular pedicled flap based on the nasoseptal artery. Patients with extensive skull base defects can undergo effective repair with dual flaps or triple flaps using these pedicled vascularized flaps. CONCLUSIONS Multiple pedicled flaps are available for reconstitution of the skull base. Knowledge of the surgical anatomy of these flaps is crucial for the skull base surgeon. These vascularized tissue flaps can be used effectively as single or combination flaps. Multilayered closure of cranial base defects with vascularized tissue can be used safely and may lead to excellent repair outcomes. PMID:26613175

  19. Superficial circumflex iliac artery pure skin perforator-based superthin flap for hand and finger reconstruction.

    PubMed

    Narushima, Mitsunaga; Iida, Takuya; Kaji, Nobuyuki; Yamamoto, Takumi; Yoshimatsu, Hidehiko; Hara, Hisako; Kikuchi, Kazuki; Araki, Jun; Yamashita, Shuji; Koshima, Isao

    2016-06-01

    For hand and finger reconstruction, thin and flexible skin coverage is ideally required. A free flap is one of the surgical options used for large defects. However, a flap containing the fat layer is bulky. Several debulking surgeries are often needed for aesthetic and functional purposes. To overcome this disadvantage, we herein report our experience of six cases of hand and finger reconstruction using a pure skin perforator (PSP) flap concept. A PSP flap is a thin skin flap that is vascularized by a perforator branch penetrating the dermis. The thickness of the PSP flap could be approximately ≤2 mm as needed. The superficial circumflex iliac artery and superficial inferior epigastric artery were used as a flap pedicle. Secondary defatting operations were not required. For the success of PSP flap elevation, we applied three techniques: the microdissection technique for vessel separation, thin flap elevation at the superficial fascial layer, and the temporary clamping method. Temporary clamping was applied for the main trunk of pedicle vessels during debulking to prevent unwanted bleeding, which allowed us to freely perform three-dimensional defatting. Using these three techniques, the PSP flap can be elevated and adjusted for complex contouring of the hand and finger. Although the use of the PSP flap requires further study, the PSP flap is an effective, superthin flap with the advantages of both skin graft and perforator flaps. PMID:27085610

  20. Clinical experience of multiple flaps for the reconstruction of dorsal digital defects

    PubMed Central

    Jiao, Hongsheng; Ding, Xiaoheng; Liu, Yujie; Zhang, Hongxun; Cao, Xuecheng

    2015-01-01

    Objective: In this report, we present our experience with reconstruction of the skin defects on the dorsum of the digits using multiple flaps. Methods: Between November 2010 and March 2013, 45 patients with dorsal digital defects underwent reconstruction using homodigital dorsal digital fasciocutaneous flap (n = 17), heterodigital dorsal digital fasciocutaneous flap (n = 14), dorsal metacarpal artery fasciocutaneous flap (n = 8) and free venous flaps (n = 6). The average flap size was 1.5 × 1.5 cm to 2.0 × 2.5 cm. Donor sites were covered with full-thickness skin graft. Results: All flaps survived completely and the donor sites healed without complications. The mean follow-up period was 18 weeks. During the follow up period, 7 patients treated with reverse homodigital fasciocutaneous flaps developed swelling in the distal portion of flaps, 3 patients treated with reverse dorsal metacarpal artery fasciocutaneous flaps developed mild swelling in the distal portion of flaps but survive well, and 4 patients treated with free venous flaps experienced venous congestion. Of the 14 patients treated with heterodigital fasciocutaneous flaps, there were 11 cases with a retrograde pedicle and 3 cases with a direct pedicle. No full-thickness graft necrosis was noted. Conclusion: Multiple options are available for the repair of skin defects on the dorsum of the digits. Besides, the use of a heterodigital fasciocutaneous flap was a simple, safe, and less invasive regimen for repairing dorsal digital skin defects. PMID:26770401

  1. Wind-tunnel investigation of an NACA 23030 airfoil with various arrangements of slotted flaps

    NASA Technical Reports Server (NTRS)

    Recant, I G

    1940-01-01

    AN investigation was made of a large-chord NACA 23030 airfoil with a 40- and a 25.66 percent-chord slotted flap to determine the section aerodynamic characteristics of the airfoil affected by flap chord, slot shape, flap position, and flap deflection. The flap positions for maximum lift, the position for minimum drag at moderate and high lift coefficients, and the complete section aerodynamic characteristics of selected optimum arrangements are given. Envelope polar of various flap arrangements are included. The relative merits of slotted flaps of different chords on the NACA 23030 airfoil are discussed, and a comparison is made of each flap size with a corresponding flap size on the NACA 23021 and 23012 airfoils. The lowest profile drags at moderate lift coefficients were obtained with an easy entrance to the slot. The 25.66-percent-chord slotted flap gave lower drag than the 40-percent-chord flap for lift coefficients less than 1.8, but the 40-percent-chord flap gave considerably lower drag for lift coefficients. The drag coefficients at moderate and high lift coefficients were greater with both sizes of flap on the NACA 23030 airfoil than on either the NACA 23021 or the NACA 23012 airfoil. The maximum lift coefficient for the deflections tested with either flap was practically independent of airfoil.

  2. 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.

  3. The Science of Hyperbaric Oxygen for Flaps and Grafts.

    PubMed

    Gould, Lisa J; May, Todd

    2016-04-01

    Hyperbaric oxygen (HBO) therapy is a versatile modality that has applications across several medical fields. HBO therapy has become a valuable asset in the management of compromised tissue grafts and flaps. Although classified together, grafts and flaps are distinctly different, in that grafts depend on the wound bed for revascularization, whereas flaps have an inherent blood supply. Evidence has shown that in a compromised graft suffering from hypoxia, HBO can maximize viability and reduce the need for repeat grafting. By comparison, compromised flaps can suffer from both ischemic and reperfusion injury, which can also be attenuated by HBOT to maximize viability. The beneficial effects of HBO occur by several mechanisms, including hyper-oxygenation, fibroblast proliferation, collagen deposition, angiogenesis, and vasculogenesis. Animal studies have demonstrated several of these mechanisms, including an increase in the number, size, and growth distance of blood vessels after HBO. Likewise, clinical studies have found positive responses in multiple types of tissue grafts and flaps, with some cases involving irradiated fields. Altogether, the data emphasizes that early identification of flap or graft compromise is absolutely critical, with maximized chance for viability when HBO is initiated as soon as possible. PMID:27042776

  4. "Reposition-flap": A therapeutic alternative in fingertips amputations.

    PubMed

    Robert, N; Chassat, R; Couturier, C; Delpit, X; Masmejean, E

    2015-08-01

    After trans-phalanx fingertips amputations, there is usually a therapeutic problem related to the distal fragment quality. Replantation is not always possible. The aim of this study was to propose the "reposition-flap" surgical procedure as an alternative solution to various surgical strategies for distal stump coverage. It consisted in the association of a bone fragment osteosyntesis and a pedicular local flap implementation. Between 2001 and 2011, the reposition-flap surgical procedure was retrospectively tested in two hand trauma centers. We reviewed a cohort of 51 patients divided in two groups. The first one (20 patients) was the "reposition-flap" group, the second (31 patients) had a coverage with an other surgical procedure (simple regularisation or local flap). Sensibility, pulp trophicity, fingers mobility, digital length, nail appearance and radiologic consolidation of each patient were reviewed. "Reposition-flap" allowed 80% length of phalanx conservation. In comparison with regularisation, the aesthetic aspects of the nail's finger (no claw) were improved with this surgical procedure. However, the Quick DASH average revealed significant statistical differences instead of the statistics obtained with the mobility of the IPD and the sensitivity of the pulp. This procedure gave best aesthetic and functional results. PMID:25001417

  5. [PELVIC FLOOR RECONSTRUCTION AFTER PELVIC EVISCERATION USING GRACILIS MUSCULOCUTANEOUS FLAP].

    PubMed

    Pavlov, V N; Bakirov, A A; Kabirov, I R; Izmajlov, A A; Kutlijarov, L M; Safiullin, R L; Urmancev, M F; Sultanov, I M; Abdrahimov, R V

    2015-01-01

    Evisceration of the pelvic organs (EPO) is a fairly uncommon surgical treatment that removes all organs from a patient's pelvic cavity. We use gracilis musculocutaneous flap to repair pelvic floor after EPO. Over the period from November 2013 to December 2014 we carried out EPO with reconstructive repair of the pelvic floor with gracilis musculocutaneous flap in 10 patients with locally advanced pelvic tumors. We describe the surgical procedure and surgical outcomes in these patients. Mean age of the patients was 55 years. Mean duration of EPO with the pelvic floor repair was 285 min., mean blood loss--595 mL and the average length of hospital stay--19 days. Gracilis musculocutaneous flap has a sufficient arterial supply and mobility for pelvic floor reconstruction. Necrosis of flap's distal edge occurred in one of the 10 clinical cases, while the remaining flaps were fully preserved. Complete healing of wounds with no signs of weakening of the pelvic floor muscles was observed in all cases. Pelvic floor reconstruction is an essential procedure in order to reduce complications associated with the evisceration of the pelvic organs. The Gracilis musculocutaneous flap is the logical alternative to repair pelvic floor defect. It does not contribute to complications like functional deficiency of the lower limbs, complications of stoma formation or weakening of the muscles of the anterior abdominal wall. PMID:26390558

  6. 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.

  7. 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

  8. Flap Dynamics in Aspartic Proteases: A Computational Perspective.

    PubMed

    Mahanti, Mukul; Bhakat, Soumendranath; Nilsson, Ulf J; Söderhjelm, Pär

    2016-08-01

    Recent advances in biochemistry and drug design have placed proteases as one of the critical target groups for developing novel small-molecule inhibitors. Among all proteases, aspartic proteases have gained significant attention due to their role in HIV/AIDS, malaria, Alzheimer's disease, etc. The binding cleft is covered by one or two β-hairpins (flaps) which need to be opened before a ligand can bind. After binding, the flaps close to retain the ligand in the active site. Development of computational tools has improved our understanding of flap dynamics and its role in ligand recognition. In the past decade, several computational approaches, for example molecular dynamics (MD) simulations, coarse-grained simulations, replica-exchange molecular dynamics (REMD) and metadynamics, have been used to understand flap dynamics and conformational motions associated with flap movements. This review is intended to summarize the computational progress towards understanding the flap dynamics of proteases and to be a reference for future studies in this field. PMID:26872937

  9. 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

  10. 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. PMID:26980600

  11. 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

  12. 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

  13. 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

  14. 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.

  15. Successful reconstruction of irradiated anterior skull base defect using the dual flap technique involving local pericranial flap and radial forearm free flap.

    PubMed

    Yeo, In Sung; Kim, Se-Hyuk; Park, Myong Chul; Lim, Hyoseob; Kim, Joo Hyoung; Lee, Il Jae

    2014-07-01

    Skull base reconstruction presents a challenging therapeutic problem requiring a multispecialty surgical approach and close cooperation between the neurosurgeon, head and neck surgeon, as well as plastic and reconstructive surgeon during all stages of treatment. The principal goal of skull base reconstruction is to separate the intracranial space from the nasopharyngeal and oropharyngeal cavities, creating support for the brain and providing a water-tight barrier against cerebrospinal fluid leakage and ascending infection. We present a case involving a 58-year-old man with anterior skull base defects (2.5 cm × 3 cm) secondary to the removal of olfactory neuroblastoma. The patient received conventional radiation therapy at 6000 cGy in 30 fractions approximately a month before tumor removal. The patient had radiation therapy before surgery and was planned to have postoperative radiation therapy, which would lead to a higher complication rate of reconstruction. Artificial dura was used for the packing of the dural defect, which was also suspected to increase the complication rate of reconstruction. For these reasons, we chose to apply the dual flap technique, which uses both local pericranial flap and de-epithelized radial forearm free flap for anterior skull base defect to promote wound healing. During 28 months of follow-up after coverage of the anterior skull base defect, the dual flap survived completely, as confirmed through follow-up magnetic resonance imaging. The patient was free of cerebrospinal fluid leakage, meningitis, and abscess, and there was minimal donor-site morbidity of the radial forearm free flap. Reconstruction of anterior skull base defects using the dual flap technique is safe, reliable, and associated with low morbidity, and it is ideal for irradiated wounds and low-volume defects. PMID:24902109

  16. Combining flaps. Medical canthal/lateral nasal root reconstruction utilizing glabellar "fan" and cheek rotation flaps--an O-to-Z variation.

    PubMed

    Field, L M; Dachow-Siwiec, E; Szymanczyk, J

    1994-03-01

    An increased use of multiple flaps applied to single reconstructive problems is encouraged. Removal of a basal cell carcinoma involving the medial canthus and adjacent lateral nasal root skin resulted in significant defect. When a glabellar "fan" flap failed to provide adequate tissue for canthal reconstruction without undue distortion, a preplanned medial cheek rotation flap followed sequentially in the repair process. The basic principles of an O-to-Z flap reconstruction were therefore fulfilled by conjoining two different flap design applications. PMID:8151035

  17. Perforator anatomy of the radial forearm free flap versus the ulnar forearm free flap for head and neck reconstruction.

    PubMed

    Hekner, D D; Roeling, T A P; Van Cann, E M

    2016-08-01

    The aim of this study was to investigate the vascular anatomy of the distal forearm in order to optimize the choice between the radial forearm free flap and the ulnar forearm free flap and to select the best site to harvest the flap. The radial and ulnar arteries of seven fresh cadavers were injected with epoxy resin (Araldite) and the perforating arteries were dissected. The number of clinically relevant perforators from the radial and ulnar arteries was not significantly different in the distal forearm. Most perforators were located in the proximal half of the distal one third, making this part probably the safest location for flap harvest. Close to the wrist, i.e. most distally, there were more perforators on the ulnar side than on the radial side. The ulnar artery stained 77% of the skin surface area of the forearm, showing the ulnar forearm free flap to be more suitable than the radial forearm free flap for the restoration of large defects. PMID:27012603

  18. 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

  19. Development of a Mouse Model of Abdominal Cutaneous Flaps for Breast Reconstruction

    PubMed Central

    Womac, Daniel John; Palanisamy, Arun Prathap; Eslick, Rene; Schimpf, Dennis Kenneth; Chavin, Kenneth David

    2013-01-01

    Autologous tissue transfer, in addition to replacing tissue that was lost during injury or surgery, offers women an excellent option to improve cosmetic appearance and self-confidence following mastectomy due to breast cancer. However, flap necrosis is a complication in obese patients undergoing this procedure. We created a mouse model to study the flap-related complications that leads to decreased flap survival in autologous breast reconstruction. Methods Left superficial inferior epigastric (SIE) pedicle abdominal-cutaneous flaps were elevated in 8 week-old, obese ob/ob male mice and their lean littermates. Flaps were followed by serial photography. Area of flap necrosis was measured at 7 days. Statistical analysis was performed. Results Necrosis was observed at the distal margin of the flaps, in both lean and obese groups. Lean left SIE flaps (n = 8) had a total area flap necrosis of 9.1% at 7 days whereas obese left SIE flaps (n = 8) had a total area flap necrosis of 45.5% at 7 days. Obese flaps had a statistically significant increase in necrosis compared to the lean flaps, p = 0.001. Conclusions There was a significant difference between flap survival in lean and obese SIE pedicle flaps in our mouse model. We have developed the first flap model of obesity utilizing the superficial epigastric pedicle in the mouse. This model is optimal for future studies to dissect out mechanisms that lead to the complications related to flap survival for breast reconstruction, especially in obese subjects. PMID:23308122

  20. 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.

  1. Management of complications and compromised free flaps following major head and neck surgery.

    PubMed

    Kucur, Cuneyt; Durmus, Kasim; Uysal, Ismail O; Old, Matthew; Agrawal, Amit; Arshad, Hassan; Teknos, Theodoros N; Ozer, Enver

    2016-01-01

    Microvascular free flaps are preferred for most major head and neck reconstruction surgeries because of better functional outcomes, improved esthetics, and generally higher success rates. Numerous studies have investigated measures to prevent flap loss, but few have evaluated the optimal treatment for free flap complications. This study aimed to determine the complication rate after free flap reconstructions and discusses our management strategies. Medical records of 260 consecutive patients who underwent free flap reconstructions for head and neck defects between July 2006 and June 2010 were retrospectively reviewed for patient and surgical characteristics and postoperative complications. The results revealed that microvascular free flaps were extremely reliable, with a 3.5 % incidence of flap failure. There were 78 surgical site complications. The most common complication was neck wound infection, followed by dehiscence, vascular congestion, abscess, flap necrosis, hematoma, osteoradionecrosis, and brisk bleeding. Twenty patients with poor wound healing received hyperbaric oxygen therapy, which was ineffective in three patients who eventually experienced complete flap loss. Eleven patients with vascular congestion underwent medicinal leech therapy, which was effective. Among the 78 patients with complications, 44 required repeat surgery, which was performed for postoperative brisk bleeding in three. Eventually, ten patients experienced partial flap loss and nine experienced complete flap loss, with the latter requiring subsequent pectoralis major flap reconstruction. Microvascular free flap reconstruction represents an essential and reliable technique for head and neck defects and allows surgeons to perform radical resection with satisfactory functional results and acceptable complication rates. PMID:25575841

  2. Extended Anterolateral Thigh Flaps for Reconstruction of Extensive Defects of the Foot and Ankle

    PubMed Central

    Liu, Lifeng; Cao, Xuexin; Zou, Lin; Li, Zongyu; Cao, Xuecheng; Cai, Jinfang

    2013-01-01

    The anterolateral thigh flap has been used for coverage of defects in the foot and ankle for years. Conventional extended anterolateral thigh flaps do not undergo thinning procedures, which limit their application. Here, a clinical series of 24 patients is reported in which extended anterolateral thigh flaps were used for posttraumatic foot and ankle reconstruction. Of the 24 flaps, 14 were simple extended anterolateral thigh fasciocutaneous flaps and 10 were thinned extended anterolateral thigh flaps. One artery and two veins, including a superficial vein and an accompanying vein, were anastomosed to vascularize each flap. Follow-up of the 24 patients ranged from 10 months to 4 years postoperatively. All 24 flaps survived successfully, except one case that had partial flap necrosis distally due to excessive thinning. The cutaneous flap territory ranged from 250 cm2 to 400 cm2 (mean, 297 cm2). Only one patient received a debulking procedure. No ulceration occurred in any of the flaps due to contact with the shoe. The extended anterolateral thigh flap is a good alternative for extensive soft tissue defects of the foot and ankle. This study also supports the high reliability and excellent vascular supply of moderate thinned extended ALT flaps. PMID:24376731

  3. Increasing options in autologous microsurgical breast reconstruction: four free flaps for 'stacked' bilateral breast reconstruction.

    PubMed

    Rozen, Warren Matthew; Patel, Nakul Gamanlal; Ramakrishnan, Venkat V

    2016-04-01

    For autologous breast reconstruction, there are cases where one free flap cannot provide the volume of tissue required, and the concept of 'stacked' bilateral deep inferior epigastric artery (DIEP) flaps was developed, in which hemi-abdominal flaps are raised on each deep inferior epigastric artery (DIEA), and both flaps transferred to the chest. In cases of bilateral breast reconstruction, stacked flaps may be required to achieve volume replacement, however options are not described. We demonstrate the use of stacked free flaps for bilateral breast reconstruction, using one DIEP flap stacked with one transverse upper gracilis (TUG) flap for each side. A 49-year-old woman, with BRCA1 mutation, presented for risk reduction mastectomies. Flap design was planned to achieve maximal projection and primary nipple reconstruction. This was able to be achieved by using the DIEP flap de-epithelialised and completely buried, with the flap orientated with the pedicle on its superficial surface, and the TUG flap lying superficially with its skin paddle used for nipple reconstruction and able to be monitored clinically. There were no flap or donor related complications and good aesthetic outcomes were achieved. This technique offers a further option in microsurgical breast reconstruction for patients in whom there is a paucity of abdominal tissue for reconstruction. PMID:27047791

  4. Scapular Tip Free Flap for Head and Neck Reconstruction

    PubMed Central

    Choi, Nayeon; Cho, Jae-Keun; Jang, Jeon Yeob; Cho, Jung Kyu; Cho, Young Sang

    2015-01-01

    Objectives Head and neck reconstruction is still challenging in terms of esthetic and functional outcomes. This study investigated the feasibility of the angular branch-based scapular tip free flap (STFF). Methods This was a retrospective study of 17 patients undergoing maxillectomy and mandibulectomy and either primary or secondary reconstruction by STFF. This study included surgical, esthetic, and functional outcomes, and detailed data are presented regarding the flap, such as pedicle length, size of the harvested bone, and failure rate. Medical photographs were used to estimate the esthetic outcome, and computed tomography was used to check the flap status postoperatively. Results The data were collected from April 2013 to April 2014. Eight patients underwent maxillary reconstruction, and nine underwent mandibular reconstruction. Maxillary defects usually included unilateral alveolar structures and the palate; mandibular defects were usually those involving mandibular angle and short segment. Vein grafting was not required in any of the patients. Flap failure occurred in one of the 17 patients (5.9%) with successful reconstruction after revision. Of the eight maxillectomy patients, orbital revisions for diplopia after maxillary reconstruction were performed in two patients (25%), and oroantral fistula repair was performed in one patient (12.5%). Conclusion This study demonstrated the reconstructive advantages of the angular branch-based STFF, long pedicle, low flap failure, 3-dimensional nature of bone and soft tissues (chimeric flap), and small rate of donor site morbidity with free ambulation. This flap is an excellent option for use in complex three-dimensional head and neck reconstruction. PMID:26622965

  5. 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

  6. 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

  7. 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.

  8. Rotor Flapping Response to Active Control

    NASA Technical Reports Server (NTRS)

    Nguyen, Khanh; Johnson, Wayne

    2004-01-01

    Rotor active control using higher harmonic blade pitch has been proposed as a means to reduce both rotor radiated noise and airframe vibration and to enhance rotor performance. The higher harmonic input, however, can affect rotor thrust and cyclic flapping - the basic trim characteristics of the rotor. Some of the trim changes can negate the active control benefits. For example, wind tunnel test results of a full scale BO-105 rotor with individual-blade control indicate some rotor performance improvements, accompanied with changes in rotor trim, using two-per-rev blade pitch input. The observed performance benefits could therefore be a simple manifestation of the trim change rather than an efficient redistribution of the rotor airloads. More recently, the flight test of the BO-105 helicopter equip,ped with individual-blade-control actuators also reported trim changes whenever the two-per-rev blade pitch for noise reduction was activated. The pilot had to adjust the trim control to maintain the aircraft under a constant flight path. These two cases highlight the, importance of trim considerations in the application of active control to rotorcraft.

  9. Regional anesthesia alone for pediatric free flaps.

    PubMed

    Bjorklund, Kim A; Venkatramani, Hari; Venkateshwaran, Govindaswamy; Boopathi, Vadivel; Raja Sabapathy, S

    2015-05-01

    Microvascular surgery plays an important reconstructive role in the pediatric population. Successful outcomes rely on surgical technique as well as anesthesia. Regional anesthesia contributes to successful free tissue transfer through sympathetic blockade, postoperative pain control, and elimination of risks and costs associated with general anesthesia. While regional anesthesia in microsurgery is discussed in the literature for adult and elderly patients, no studies focus on the pediatric population. Accordingly, this paper reviews 20 pediatric patients undergoing microvascular surgery (anterolateral thigh, n = 9; gracilis, n = 3; toe transfer, n = 6; and fibula, n = 2) with regional anesthesia and sedation. All patients underwent spinal epidural anesthesia, and seven also received brachial plexus blocks. The average duration of anesthesia was 3-4 h (anterolateral thigh (ALT) and gracilis) and 6-8 h (toe transfer and fibula). No anesthesia-related complications or flap failures occurred. We conclude that regional anesthesia has important benefits in pediatric microsurgery and it is a safe and cost-effective alternative to general anesthesia. PMID:25858275

  10. ``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.

  11. 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.

  12. Management of Large Sternal Wound Infections With the Superior Epigastric Artery Perforator Flap.

    PubMed

    Eburdery, H; Grolleau, J L; Berthier, C; Bertheuil, N; Chaput, B

    2016-01-01

    The management of sternal wound infections often requires pedicled flaps. In recent years, the emergence of perforator flaps has changed our management of wounds involving tissue loss. For sternal wounds, the superior epigastric artery perforator (SEAP) flap can be used with the propeller procedure with minimal donor site morbidity. In our practice, this flap has replaced the traditional latissimus dorsi and pectoralis major flaps in the treatment of many sternal wounds. We report our experience with 4 patients with large sternal wound infection after cardiothoracic operations. The SEAP flap appears a safe alternative for low-morbidity coverage of sternal infections. Moreover, muscle flaps remain available in case the SEAP flap fails. PMID:26694288

  13. 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.

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

    NASA Astrophysics Data System (ADS)

    McKinzie, D. J., Jr.

    1982-05-01

    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.

  15. An improved flapping wing system actuated by the LIPCA

    NASA Astrophysics Data System (ADS)

    Syaifuddin, Moh.; Park, Hoon C.; Lee, Sang K.; Byun, Do Y.

    2006-03-01

    This paper presents an improved version of the insect-mimicking flapping-wing mechanism actuated by LIPCA (Lightweight Piezo-Composite Actuator). As the previous version, the actuation displacement of the actuator is converted into flapping-wing motion by a mechanical linkage system that functioned as displacement amplifier as well. In order to provide feathering motion, the wing is attached to the axis through a hinge system that allows the wing rotation at each end of half-stroke, due to air resistance. In this improved version, the total weight has been reduced to the half of the previous one. The device could produce about 90 degree of flapping angle when it operated at around 10 Hz, which was the natural flapping-frequency. Several flapping tests under different parameter configurations were conducted in order to investigate the characteristic of the generated lift. In addition, the smoke-wire test was also conducted, so that the vortices around the wing can be visually observed. Even though the present wing has smaller wing area, it could produce higher lift then before.

  16. [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. PMID:25213485

  17. 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

  18. A Large Scale PIV Investigation of a Flap Edge Vortex

    NASA Astrophysics Data System (ADS)

    Walker, Stephen M.; Alkislar, M. B.; Lourenco, L.; Krothapalli, A.

    1996-11-01

    A recent experiment at NASA/Ames Research Center demonstrated the application of a large scale 'on-line' Particle Image Velocimetry, (PIV), in a 7' x 10' wind tunnel. Data was collected for freestream velocities in the range from approximately 40 m/sec to 100 m/sec. The flow field of interest for this investigation was a vortex that was generated by a flap edge. The model was an unswept wing, having a span of 5 ft and a chord, (c), of 2.5 ft., fitted with a half-span Fowler flap. The flap had a chord of 9 inches. Cross plane flow field velocity measurements were made at 0.6 c, (18 inches), downstream of the trailing edge of the flap. The baseline model was also tested with a three quarter-span slat, and a flap edge fence. The fence is designed to reduce noise from high-lift devices. The area of the flow encompassed within this investigation was 40 cm by 40 cm. A high resolution CCD Camera, (2048 pixels x 2048 pixels), was used to capture the double exposure images. The light source used in this experiment was a Spectra Physics PIV-400 Nd:Yag double pulsed laser, and the particle seeding was generated from a Roscoe 4500 fog machine. The velocity data obtained from the experiment was used to determine both the vorticity and the circulation.

  19. Orbital Floor Reconstruction with Free Flaps after Maxillectomy

    PubMed Central

    Sampathirao, Leela Mohan C. S. R.; Thankappan, Krishnakumar; Duraisamy, Sriprakash; Hedne, Naveen; Sharma, Mohit; Mathew, Jimmy; Iyer, Subramania

    2013-01-01

    Background The purpose of this study is to evaluate the outcome of orbital floor reconstruction with free flaps after maxillectomy. Methods This was a retrospective analysis of 34 consecutive patients who underwent maxillectomy with orbital floor removal for malignancies, reconstructed with free flaps. A cross-sectional survey to assess the functional and esthetic outcome was done in 28 patients who were alive and disease-free, with a minimum of 6 months of follow-up. Results Twenty-six patients had bony reconstruction, and eight had soft tissue reconstruction. Free fibula flap was the commonest flap used (n = 14). Visual acuity was normal in 86%. Eye movements were normal in 92%. Abnormal globe position resulted in nine patients. Esthetic satisfaction was good in 19 patients (68%). Though there was no statistically significant difference in outcome of visual acuity, eye movement, and patient esthetic satisfaction between patients with bony and soft tissue reconstruction, more patients without bony reconstruction had abnormal globe position (p = 0.040). Conclusion Free tissue transfer has improved the results of orbital floor reconstruction after total maxillectomy, preserving the eye. Good functional and esthetic outcome was achieved. Though our study favors a bony orbital reconstruction, a larger study with adequate power and equal distribution of patients among the groups would be needed to determine this. Free fibula flap remains the commonest choice when a bony reconstruction is contemplated. PMID:24436744

  20. Tracheoesophageal puncture site closure with sternocleidomastoid musculocutaneous transposition flap

    PubMed Central

    Jaiswal, Dushyant; Yadav, Prabha; Shankhdhar, Vinay Kant; Gujjalanavar, Rajendra Suresh; Puranik, Prashant

    2015-01-01

    Introduction: Tracheoesophageal voice prosthesis is highly effective in providing speech after total laryngectomy. Although it is a safe method, in certain cases dilatation or leakage occurs around the prosthesis that needs closure of tracheoesophageal fistula. Both non-surgical and surgical methods for closure have been described. Surgical methods are used when non-surgical methods fail. We present the use of the sternocleidomastoid musculocutaneous (SCMMC) transposition flap for the closure of tracheoesophageal fistula. Materials and Methods: An incision is made at the mucocutaneous junction circumferentially around the tracheostoma. Tracheoesophageal space is dissected down to and beyond the fistula. The tracheoesophageal tract is divided. The oesophageal mucosa is closed with simple sutures. Then SCMMC transposition flap is raised and transposed to cover sutured oesophagus and the defect between the oesophagus and the trachea. Results: This study was done prospectively over a period of 1 year from June 2012 to May 2013. This technique was used in patients with pliable neck skin. In nine patients, this procedure was done (inferior based flap in nine cases) and it was successful in eight patients. In one case, there was dehiscence at the leading edge of flap with oesophageal dehiscence, which required a second procedure. In two cases, there was marginal necrosis of flap, which healed without any intervention. Nine patients in this series were post-radiation. Conclusion: This method of closure is simple and effective for patients with pliable neck skin, who require permanent closure of the tracheoesophageal fistula. PMID:26933281

  1. Repair of a canine forelimb skin deficit by microvascular transfer of a caudal superficial epigastric flap.

    PubMed

    Lewin, G A; Smith, J H

    2010-02-01

    Extensive skin loss from the forelimb of a Border collie was repaired by a microvascular caudal superficial epigastric flap, with secondary meshing of the flap to increase coverage. The caudal superficial epigastric artery and vein were anastomosed to the brachial artery and vein. End-to-end anastomosis to the brachial artery and vein did not compromise peripheral blood flow, and no flap necrosis was observed after subsequent limited meshing of the flap. PMID:20070493

  2. 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.

  3. Free craniotomy versus osteoplastic craniotomy, assessment of flap viability using 99mTC MDP SPECT.

    PubMed

    Shelef, Ilan; Golan, Haim; Merkin, Vladimir; Melamed, Israel; Benifla, Mony

    2016-09-01

    There are currently two accepted neurosurgical methods to perform a bony flap. In an osteoplastic flap, the flap is attached to surrounding muscle. In a free flap, the flap is not attached to adjacent tissues. The former is less common due to its complexity and the extensive time required for the surgery; yet the rate of infection is significantly lower, a clear explanation for which is unknown. The objective of this study was to test the hypothesis that the osteoplastic flap acts as a live implant that resumes its blood flow and metabolic activity; contrasting with the free flap, which does not have sufficient blood flow, and therefore acts as a foreign body. Seven patients who underwent craniotomy with osteoplastic flaps and five with free flaps had planar bone and single photon emission computed tomography (SPECT) scans of the skull at 3-7days postoperative, after injection of the radioisotope, 99m-technetium-methylene diphosphonate (99m-Tc-MDP). We compared radioactive uptake as a measure of metabolic activity between osteoplastic and free flaps. Mean normalized radioactive uptakes in the centers of the flaps, calculated as the ratios of uptakes in the flap centers to uptakes in normal contralateral bone, were [mean: 1.7 (SD: 0.8)] and [0.6 (0.1)] for the osteoplastic and free flap groups respectively and were [2.4 (0.8)] and [1.3 (0.4)] in the borders of the flaps. Our analyses suggest that in craniotomy, the use of an osteoplastic flap, in contrast to free flap, retains bone viability. PMID:27068014

  4. Effect of flap deflection on the lift coefficient of wings operating in a biplane configuration

    NASA Technical Reports Server (NTRS)

    Stasiak, J.

    1977-01-01

    Biplane models with a lift flap were tested in a wind tunnel to study the effect of flap deflection on the aerodynamic coefficient of the biplane as well as of the individual wings. Optimization of the position flap was carried out, and the effect of changes in the chord length of the lower wing was determined for the aerodynamic structure of a biplane with a lift flap on the upper wing.

  5. 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

  6. Submental Perforator Flap Design with a Near-Infrared Fluorescence Imaging System: The Relation between Number of Perforators, Flap Perfusion, and Venous Drainage

    PubMed Central

    Matsui, Aya; Lee, Bernard T.; Winer, Joshua H.; Laurence, Rita G.; Frangioni, John V.

    2009-01-01

    Background The submental flap is a reliable alternative to microsurgical reconstruction of facial deformities, providing an excellent cosmetic match with the contour and color of the face. In this study, we evaluated submental flap design by employing near-infrared (NIR) fluorescence angiography to identify perforator arteries (PAs). The impact of the number of preserved PAs on flap perfusion and venous drainage were quantified. Methods Indocyanine green was injected intravenously into n = 18 pigs. Three groups of 6 animals each had one, two, or three PAs preserved. The FLARE™ NIR fluorescence imaging system was employed for image acquisition. Images were recorded before and after flap creation, and every h, for 6 h. The time to maximum perfusion, the drainage ratio (an indicator of venous drainage), and the percentage of perfused flap area were analyzed statistically at each time point. Results Flaps with a single dominant PA had an initial mean perfused area of 80%, which improved to 97% at 6 h. For flaps with two and three preserved PAs, perfused area at 6 h was 99.8% and 100%, respectively. A significant increase was observed in all three metrics as more vessels were preserved. Regardless of the number of PAs preserved, though, all three metrics improved over 6 h. Conclusions NIR fluorescence angiography can reliably identify submental PAs for flap design, and can be used to assess flap perfusion and venous drainage in real-time. Flap metrics at 6 h were equivalent when either one, or multiple PAs, were preserved. PMID:19935293

  7. My First 100 Consecutive Microvascular Free Flaps: Pearls and Lessons Learned in First Year of Practice

    PubMed Central

    2013-01-01

    Background: Microvascular reconstruction for oncologic defects is a challenging and rewarding endeavor, and successful outcomes are dependent on a multitude of factors. This study represents lessons learned from a personal prospective experience with 100 consecutive free flaps. Methods: All patients’ medical records were reviewed for demographics, operative notes, and complications. Results: Overall 100 flaps were performed in 84 consecutive patients for reconstruction of breast, head and neck, trunk, and extremity defects. Nineteen patients underwent free flap breast reconstruction with 10 patients undergoing bilateral reconstruction and 2 patients receiving a bipedicle flap for reconstruction of a unilateral breast defect. Sixty-five free flaps were performed in 61 patients with 3 patients receiving 2 free flaps for reconstruction of extensive head and neck defects and 1 patient who required a second flap for partial flap loss. Trunk and extremity reconstruction was less common with 2 free flaps performed in each group. Overall, 19 patients (22.6%) developed complications and 14 required a return to the operating room. There were no flap losses in this cohort. Thorough preoperative evaluation and workup, meticulous surgical technique and intraoperative planning, and diligent postoperative monitoring and prompt intervention are critical for flap success. Conclusions: As a young plastic surgeon embarking in reconstructive plastic surgery at an academic institution, the challenges and dilemmas presented in the first year of practice have been daunting but also represent opportunities for learning and improvement. Skills and knowledge acquired from time, experience, and mentors are invaluable in optimizing outcomes in microvascular free flap reconstruction. PMID:25289221

  8. 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.

  9. Analytic review of 2372 free flap transfers for head and neck reconstruction following cancer resection.

    PubMed

    Nakatsuka, Takashi; Harii, Kiyonori; Asato, Hirotaka; Takushima, Akihiko; Ebihara, Satoshi; Kimata, Yoshihiro; Yamada, Atsushi; Ueda, Kazuki; Ichioka, Shigeru

    2003-08-01

    Microvascular free tissue transfer has gained world-wide acceptance as a means of reconstructing post-oncologic surgical defects in the head and neck region. Since 1977, the authors have introduced this reconstructive procedure to head and neck reconstruction after cancer ablation, and a total of 2372 free flaps were transferred in 2301 patients during a period of over 23 years. The most frequently used flap was the rectus abdominis flap (784 flaps: 33.1 percent), followed by the jejunum (644 flaps: 27.2 percent) and the forearm flap (384 flaps: 16.2 percent). In the reported series, total and partial flap necrosis accounted for 4.2 percent and 2.5 percent of cases, respectively. There was a significant statistical difference ( p < 0.05) in complete flap survival rate between immediate and secondary reconstruction cases. The authors believe that the above-mentioned three flaps have been a major part of the armamentarium for head and neck reconstruction because of a lower rate of flap necrosis, compared to other flaps. PMID:14515225

  10. Propeller Perforator Flaps in Distal Lower Leg: Evolution and Clinical Applications

    PubMed Central

    2012-01-01

    Simple or complex defects in the lower leg, and especially in its distal third, continue to be a challenging task for reconstructive surgeons. A variety of flaps were used in the attempt to achieve excellence in form and function. After a long evolution of the reconstructive methods, including random pattern flaps, axial pattern flaps, musculocutaneous flaps and fasciocutaneous flaps, the reappraisal of the works of Manchot and Salmon by Taylor and Palmer opened the era of perforator flaps. This era began in 1989, when Koshima and Soeda, and separately Kroll and Rosenfield described the first applications of such flaps. Perforator flaps, whether free or pedicled, gained a high popularity due to their main advantages: decreasing donor-site morbidity and improving aesthetic outcome. The use as local perforator flaps in lower leg was possible due to a better understanding of the cutaneous circulation, leg vascular anatomy, angiosome and perforasome concepts, as well as innovations in flaps design. This review will describe the evolution, anatomy, flap design, and technique of the main distally pedicled propeller perforator flaps used in the reconstruction of defects in the distal third of the lower leg and foot. PMID:22783507

  11. [Experience with the s-GAP flap for autologous breast reconstruction].

    PubMed

    Werdin, F; Peek, A; Schuster, H; Baumeister, S

    2008-08-01

    In breast reconstruction with autologous tissue the DIEP flap has become the gold standard in recent years. The superior gluteal artery perforator (s-GAP) flap is an alternative harvested from the buttock. We present our experience with the s-GAP flap and discuss its role in breast reconstruction. All s-GAP flaps performed for breast reconstruction in the Department of Plastic and Hand Surgery, Behandlungszentrum Vogtareuth from June 2002 until February 2007 were retrospectively analysed. Out of 59 flaps 4 flaps failed, the success rate was 94 %. Partial or fat necrosis occurred in 2 cases. The s-GAP flap served as a safe reconstructive alternative to the DIEP flap. Advantages of the s-GAP flap are reliable perforators, the safe vascular supply and the firm fat structure which facilitates the breast reconstruction. The donor site morbidity is minimal, the gluteal muscles stay intact and the scar is easy to hide in the underwear. Disadvantages are a demanding preparation with a prolonged operating time compared to the DIEP flap. The s-GAP flap is a reliable and safe option for autologeous breast reconstruction. It is the method of choice for staged bilateral breast reconstruction or if the DIEP flap is not available, particularly in the thin patient. PMID:18716984

  12. Application of free radial forearm flap in reconstruction of the face and oral cavity.

    PubMed

    Tvrdek, M; Nejedlý, A; Kletenský, J; Pros, Z

    1994-01-01

    The authors have shown the possibilities of application of the free radial forearm flap in clinical cases when reconstructing defects in the region of the face and of oral cavity. This flap is particularly useful in cases where it is necessary to duplicate the flap and to reconstruct two layers at the same time. PMID:7618399

  13. Deep circumflex iliac artery (DCIA) free flap without DCIA: report of a unique case.

    PubMed

    Jairath, David; Hage, J Joris

    2004-10-01

    The iliac crest free flap is a reliable source of cancellous bone, muscle, and skin. The vascularization of this flap arises from the deep circumflex iliac artery (DCIA) which allegedly is always present. The authors report a unique case of successful microvascular transplantation of an iliac crest osteomyocutaneous free flap in a patient in whom the DCIA and DCIV were absent. PMID:15534778

  14. 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…

  15. Combination Nasolabial Transposition Flap and Island Pedicle Flap Following Mohs Surgery of Simultaneous Basal Cell Carcinomas Involving Both Nasal Alae

    PubMed Central

    Lee, Chae Young; Lee, Yeong Kyu; Choi, Kyu Won; Lee, Chae Wook; Kim, Ki Ho

    2008-01-01

    The nasal ala is a challenging area for surgical reconstruction, with thick sebaceous skin, the lack of an ample tissue reservoir, and an adjacent free margin. Numerous flaps have been reported for the repair of alae defects. A 71-year-old woman with simultaneous basal cell carcinomas involving both nasal alae was treated by Mohs micrographic surgery. The surgical defects measured 1.5×1.5 cm on the center of the right nasal ala and 1.0×1.0 cm on the left nasal ala, including the alar crease and rim. The right nasal ala was used as a nasolabial transposition flap and the left nasal ala was reconstructed by an island pedicle flap. The final shape and texture were satisfactory. The flaps survived and nasal symmetry was preserved. Combined nasolabial transposition and island pedicle flaps thus offer a superior esthetic and functional result owing to minimized tension. This may be a valuable reconstructive option in the repair of bilateral nasal alae defects.

  16. Interaction of Two Flapping Flags in Axial Flow

    NASA Astrophysics Data System (ADS)

    Gunter, Amy-Lee; Fayed, Mohamed; Abderrahmane, Hamid Ait; Paidoussis, Michael P.; Ng, Hoi Dick

    2010-11-01

    The flapping of two parallel flags in axial low turbulence flow is investigated experimentally inside a small scale wind tunnel test section. The variables of the problem are the size and flexural rigidity of the flags, and the distance that separates the two flags. The flow velocity represents the control parameter that governs the coupling and flapping mode of the flags. Two flapping modes, in-phase and out-of-phase modes, were observed in the experiment. Image processing technique was used and the time series of a given point on the flag edge was analyzed. The stability condition of the flags was obtained and compared to the recent theoretical models. The dynamics of the coupling between the two flags is also studied.

  17. 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.

  18. The Autospreader Flap for Midvault Reconstruction following Dorsal Hump Resection.

    PubMed

    Moubayed, Sami P; Most, Sam P

    2016-02-01

    Dorsal hump reduction without adequate reconstitution of the midvault can often result in cosmetic or functional problems. One of the simplest techniques to avoid these problems is the use of the excess upper lateral cartilage to reconstruct the midvault (the spreader flap or autospreader). Herein we outline the history of the technique and present the specific indications and contraindications, as well as describe our method for achieving it successfully. Case studies are presented with the specific indications. Grafting alternatives to the spreader flap are also outlined. The spreader flap technique offers multiple advantages, including maximal use of local tissues, simplicity, and airway preservation. Disadvantages are the use of an external approach and the inability to use it alone in the presence of severe asymmetries. PMID:26862962

  19. 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.

  20. The role of flaps and grafts in modern hypospadiology

    PubMed Central

    Wallis, M. Chad; Braga, Luis; Khoury, Antoine

    2008-01-01

    The modern hypospadiologist must be proficient in the use of both vascularized flaps and free grafts. When choosing a repair for any given patient with hypospadias, one must consider the length of the urethroplasty, the presence and degree of ventral curvature and perhaps most importantly, the surgeon’s own experience. Not all repairs are created equally and different complication rates and cosmetic outcomes can be seen among different surgeons utilizing the same technique. Each surgeon tends to infuse their own modifications to any given technique and many of these modifications go unreported. It is incumbent upon each surgeon to be familiar with a wide variety of techniques, which invariably includes the use of flaps and grafts. We present a spectrum of the uses of flaps and grafts in modern hypospadiology. PMID:19468398

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Interactions between butterfly scales and unsteady flows during flapping flight

    NASA Astrophysics Data System (ADS)

    Jones, Robert; Lang, Amy

    2008-11-01

    Recent research has shown that the highly flexible wings of butterflies in flapping flight develop vortices along their leading and trailing edges. Butterfly scales (approximately 100 microns) have a shingled pattern and extend into the boundary layer. These scales could play a part in controlling separation in this 3-dimensional complex flow field. Biomimetic applications of butterfly scales may aid in the development of flapping wing micro air vehicles. In this study, we observed that the orientation of the scales may relate to the local flow field, and might move or shift during flight. Monarch butterflies were trained to fly in a low speed smoke tunnel for visualization. Scales were removed from the leading and trailing edges and specimens were photographed at 500 frames per second. Variation in flapping pattern and flight fitness are discussed.

  6. 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.

  7. 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.

  8. 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.

  9. Hyperbaric oxygen (HBO2) treatment for a failing facial flap.

    PubMed

    McCrary, Brian F

    2007-01-01

    Hyperbaric oxygen (HBO2) is an approved treatment for 13 pathological entities. One of these indications--a failing facial flap--is presented in this case report of a traumatic wound to the face and right axilla after an unprovoked pit bull attack on a 4 year old girl. Surgical repair was started acutely but the facial flap became congested and ischaemic, indicating deterioration of the blood supply. HBO2 treatments were initiated twice a day, resulting in remarkably decreased swelling and discomfort after the first treatment. Leeching was also used to assist with reduction of venous congestion in the flap. The patient was discharged 5 days later with a well perfused, mostly intact, incision with minimal tenderness. Surgical repair was required for a small area of wound dehiscence. Photographs documenting the patient's progress with HBO2 are presented. A discussion of the mechanisms of action of HBO2 and its beneficial effects is provided in this case. PMID:17267665

  10. Bowel obstruction following deep circumflex iliac artery free flap harvesting.

    PubMed

    Tan, Neil C-W; Brennan, Peter A; Senapati, Asha; Puxeddu, Roberto

    2009-12-01

    The deep circumflex iliac artery flap (DCIA) has been well described as an autograft flap used in head and neck reconstructions, particularly for large maxillary and mandibular defects. Complications, particularly at the donor site, have been well documented. Although it is considered a minor complication, herniation should not be underestimated as it can potentially lead to bowel obstruction, necessitating an emergency operation. We report a case of acute obstruction of the small bowel secondary to herniation at the donor site after harvesting a DCIA free flap for a maxillary defect, a complication that to our knowledge has been reported only once. We review the pathogenesis and possible ways to reduce the likelihood of developing this serious complication. PMID:19249144

  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. 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.

  13. 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.

  14. 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

  15. 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

  16. 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

  17. Therapeutic Outcomes of Pectoralis Major Muscle Turnover Flap in Mediastinitis

    PubMed Central

    Bagheri, Reza; Tashnizi, Mohammad Abbasi; Haghi, Seyed Ziaollah; Salehi, Maryam; Rajabnejad, Ata’ollah; Safa, Mohsen Hatami Ghale; Vejdani, Mohammad

    2015-01-01

    Background This study aimed to evaluate the therapeutic results and safety of pectoralis major muscle turnover flaps in the treatment of mediastinitis after coronary artery bypass grafting (CABG) procedures. Methods Data regarding 33 patients with post-CABG deep sternal wound infections (DSWIs) who underwent pectoralis major muscle turnover flap procedures in the Emam Reza and Ghaem Hospitals of Mashhad, Iran were reviewed in this study. For each patient, age, sex, hospital stay duration, remission, recurrence, and associated morbidity and mortality were evaluated. Results Of the 2,447 CABG procedures that were carried out during the time period encompassed by our study, DSWIs occurred in 61 patients (2.5%). Of these 61 patients, 33 patients (nine females [27.3%] and 24 males [72.7%]) with an average age of 63±4.54 years underwent pectoralis major muscle turnover flap placement. Symptoms of infection mainly occurred within the first 10 days after surgery (mean, 10.24±13.62 days). The most common risk factor for DSWIs was obesity (n=16, 48.4%) followed by diabetes mellitus (n=13, 39.4%). Bilateral and unilateral pectoralis major muscle turnover flaps were performed in 20 patients (60.6%) and 13 patients (39.4%), respectively. Complete remission was achieved in 25 patients (75.7%), with no recurrence in the follow-up period. Four patients (12.1%) needed reoperation. The mean hospitalization time was 11.69±6.516 days. Four patients (12.1%) died during the course of the study: three due to the postoperative complication of respiratory failure and one due to pulmonary thromboembolism. Conclusion Pectoralis major muscle turnover flaps are an optimal technique in the treatment of post-CABG mediastinitis. In addition to leading to favorable therapeutic results, this flap is associated with minimal morbidity and mortality, as well as a short hospitalization time. PMID:26290837

  18. Unsteady wake measurements of an oscillating flap at transonic speeds

    NASA Technical Reports Server (NTRS)

    Bodapati, S.; Lee, C.-S.

    1984-01-01

    The steady and unsteady wake profiles of an airfoil with an oscillating flap were measured at nominal free stream Mach number of 0.8 in the NASA Ames 11 x 11-foot wind tunnel. The instantaneous wake velocity and pressure profiles at four axial locations are presented up to one chord length from the trailing edge. Both fundamental harmonic frequency and typical time history data are presented to observe the effects of airfoil incidence and flap angle. The drag coefficient obtained from the wake pressure measurements is compared with that obtained from the airfoil pressure distribution.

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

    PubMed Central

    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

  20. 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

  1. Chimeric Anterolateral Thigh Flap for Total Thoracic Esophageal Reconstruction.

    PubMed

    Ruiz-Moya, Alejandro; Segura-Sampedro, Juan J; Sicilia-Castro, Domingo; Carvajo-Pérez, Francisco; Gómez-Cía, Tomás; Vázquez-Medina, Antonio; Ibáñez-Delgado, Francisco

    2016-01-01

    Gastric pull-up is generally the first choice for a total thoracic esophageal reconstruction. Malfunction of this gastric conduit is uncommon, but devastating when it occurs: it causes marked comorbidity to the patient, preventing oral intake and worsening quality of life. Secondary salvage thoracic esophageal reconstruction surgery is usually performed with free or pedicled jejunum flaps or colon interposition. We present a case of a total thoracic esophageal reconstruction with an externally monitored chimeric anterolateral thigh flap, extending from the cervical esophagus to the retrosternal gastroplasty remnant. Intestinal reconstructive techniques were not an available option for this patient. PMID:26694271

  2. 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.

  3. Spreader flaps for middle vault contour and stabilization.

    PubMed

    Kovacevic, Milos; Wurm, Jochen

    2015-02-01

    Nasal hump excision is common during septorhinoplasty. Without appropriate restoration of the middle nasal vault, cosmetic and functional problems may ensue. Recently, spreader flaps have become an established alternative to traditional spreader grafts. Typical indications include primary rhinoplasty patients with hump noses, hump/tension noses, and moderately hooked or crooked noses. When suitable patients are selected, spreader flaps and their modifications represent a reliable alternative to the standard spreader graft, and when all of the necessary prerequisites are met, this technique obviates the need for additional cartilage grafting in most cases. PMID:25430925

  4. Noise generation at the side edges of flaps

    NASA Astrophysics Data System (ADS)

    Hardin, J. C.

    1980-06-01

    The recently observed phenomenon of high noise radiation from the side edges of flaps is investigated by way of a two-dimensional model based upon a physical picture of chordwise boundary layer vorticity being swept around the edge by spanwise flow on the flap. The trajectory and resulting noise radiation for a discrete vortex in such a flow is obtained. Further, a mathematical condition for the vortex to be captured by the flow and swept around the edge is derived. The sound generation depends strongly upon the vortex strength and distance from the edge and can be more intense than trailing edge noise in agreement with experimental observations.

  5. Free style perforator based propeller flaps: Simple solutions for upper extremity reconstruction!

    PubMed Central

    Panse, Nikhil; Sahasrabudhe, Parag

    2014-01-01

    Background: The introduction of perforator flaps by Koshima et al. was met with much animosity in the plastic surgery fraternity. The safety concerns of these flaps following the intentional twist of the perforators have prevented widespread adoption of this technique. Use of perforator based propeller flaps in the lower extremity is gradually on the rise, but their use in upper extremity reconstruction is infrequently reported, especially in the Indian subcontinent. Materials and Methods: We present a retrospective series of 63 free style perforator flaps used for soft tissue reconstruction of the upper extremity from November 2008 to June 2013. Flaps were performed by a single surgeon for various locations and indications over the upper extremity. Patient demographics, surgical indication, defect features, complications and clinical outcome are evaluated and presented as an uncontrolled case series. Results: 63 free style perforator based propeller flaps were used for soft tissue reconstruction of 62 patients for the upper extremity from November 2008 to June 2013. Of the 63 flaps, 31 flaps were performed for trauma, 30 for post burn sequel, and two for post snake bite defects. We encountered flap necrosis in 8 flaps, of which there was complete necrosis in 4 flaps, and partial necrosis in four flaps. Of these 8 flaps, 7 needed a secondary procedure, and one healed secondarily. Although we had a failure rate of 12-13%, most of our failures were in the early part of the series indicative of a learning curve associated with the flap. Conclusion: Free style perforator based propeller flaps are a reliable option for coverage of small to moderate sized defects. Level of Evidence: Therapeutic IV. PMID:24987209

  6. 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

  7. 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

  8. Combined Use of the Latissimus Dorsi Musculocutaneous Flap and the Anterolateral Thigh Flap to Reconstruct an Extensive Shoulder Defect in an NF-1 Patient

    PubMed Central

    Fujiki, Masahide; Sakisaka, Masanobu; Kawai, Akira

    2016-01-01

    Summary: Soft tissue coverage after the resection of a large malignant peripheral neural sheath tumor (MPNST) is a challenge. We report the successful reconstruction of an extensive shoulder defect after MPNST resection in a patient with a type 1 neurofibromatosis with a novel combination of flaps. A 70-year-old man with type 1 neurofibromatosis presented with a recurrent MPNST on his right shoulder. He underwent a wide excision of the tumor, which resulted in a huge soft tissue defect around the shoulder joint. The resultant defect was reconstructed with a pedicled latissimus dorsi musculocutaneous flap and a free anterolateral thigh flap. The flaps survived, and the wounds healed uneventfully. His affected arm was useful. The combination of a pedicled latissimus dorsi musculocutaneous flap and a free anterolateral thigh flap is a versatile option for the reconstruction of an extensive shoulder defect. PMID:27200231

  9. 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

  10. 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

  11. 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.

  12. The Effect of the Active Ingredient Thymoquinone on Flap Viability in Random Pattern Flaps in Rats.

    PubMed

    Kocak, Omer Faruk; Bozan, Nazim; Oksuz, Mustafa; Yuce, Serdar; Demir, Canser Yılmaz; Bulut, Gulay; Ragbetli, Murat Cetin

    2016-08-01

    Thymoquinone (TQ) is a plant extract that has been shown to have antioxidant, anti-inflammatory, angiogenic, antimicrobial, and anticarcinogenic effects. The aim of this study is to research how the use of TQ affects flap viability. 42 rats were placed into 6 groups, with 7 rats in each. A 3 × 10 cm McFarlane flap model was used on the test animals. The sham group had used neither surgical nor TQ treatment. The control group had surgery but no treatment afterwards. The preoperative TQ group was given oral doses of 2 mg/kg. TQ for 10 days preoperatively with no treatment after the surgical procedure. The postoperative TQ group received oral doses of 2 mg/kg TQ for 10 days after the surgical process. The preoperative + postoperative (pre + postoperative) TQ group was given oral doses of 2 mg/kg TQ for 10 days both preoperatively and postoperatively. Finally, the dimethylsulfoxide group received 10 mg/kg dimethylsulfoxide (DMSO) for 10 days both preoperatively and postoperatively. Ten days after surgery the findings were evaluated. The average rates of necrosis were found to be 29.7 % in the control group, 19.18 % in the preoperative TQ group, 13.05 % in the postoperative TQ group, 8.42 % in the pre + postoperative TQ group, and 29.03 % in the DMSO group. The experimental groups had better area measurement, histopathological, and electron microscopic results than the control group (All; p < 0.05). We believe that, because of its antioxidant, anti-inflammatory, and angiogenic properties, thymoquinone is an agent that can prevent ischemia-reperfusion damage and, therefore, prevent necrosis. PMID:27072137

  13. 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. PMID:24589517

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. Distally based sural lesser saphenous neuro-veno-adipo-fascial (NVAF) flap for reconstruction in the foot: lessons learned.

    PubMed

    Patel, Kamlesh B; Bartholomew, Samuel V; Wong, Michael S; Stevenson, Thomas R

    2010-09-01

    We report nine cases in which the neuro-veno-adipo-fascial (NVAF) flap was used to perform reconstruction of foot wounds over a 7-year period. Complications occurred in five (56%) patients. One patient suffered total loss of the flap and four experienced partial loss of the NVAF flap. Complications are to be expected with the use of the NVAF flap for foot wounds, but in most cases the flap is salvageable. The NVAF flap is an option in foot reconstruction when free tissue transfer is not available, contraindicated due to patient factors or when a prior free flap has failed. PMID:20655007

  19. 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.

  20. 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