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Sample records for abdominal wall motion

  1. Economics of abdominal wall reconstruction.

    PubMed

    Bower, Curtis; Roth, J Scott

    2013-10-01

    The economic aspects of abdominal wall reconstruction are frequently overlooked, although understandings of the financial implications are essential in providing cost-efficient health care. Ventral hernia repairs are frequently performed surgical procedures with significant economic ramifications for employers, insurers, providers, and patients because of the volume of procedures, complication rates, the significant rate of recurrence, and escalating costs. Because biological mesh materials add significant expense to the costs of treating complex abdominal wall hernias, the role of such costly materials needs to be better defined to ensure the most cost-efficient and effective treatments for ventral abdominal wall hernias. PMID:24035086

  2. [A case of abdominal wall actinomycosis].

    PubMed

    Kim, Kyung Hoon; Lee, Jin Soo; Cho, Hyeong Jun; Choi, Seung Bong; Cheung, Dae Young; Kim, Jin Il; Lee, In Kyu

    2015-04-01

    Actinomycosis is a chronic suppurative granulomatous infectious disease caused by actinomyces species that is characterized by formation of characteristic clumps called as sulfur granules. Abdominal actinomycosis is a rare disease and is often difficult to diagnose before operation. Abdominal actinomycosis infiltrating into the abdominal wall and adhering to the colon is even rarer. Most abdominal actinomycosis develops after operation, trauma or inflammatory bowel disease, and is also considered as an opportunistic infection in immunocompromised patient with underlying malignancy, diabetes mellitus, human immunodeficiency virus infection, etc. Actinomycosis is diagnosed based on histologic demonstration of sulfur granules in surgically resected specimen or pus, and treatment consists of long-term penicillin based antibiotics therapy with or without surgical resection. Herein, we report an unusual case of abdominal wall actinomycosis which developed in a patient after acupuncture and presented as abdominal wall mass that was first mistaken for abdominal wall invasion of diverticulum perforation. PMID:25896158

  3. Abdominal wall reconstruction with implantable meshes.

    PubMed

    Masden, Derek; Felder, John M; Iorio, Matthew L; Bhanot, Parag; Attinger, Christopher E

    2011-01-01

    Abdominal wall defects present a difficult problem for the reconstructive surgeon. Over the years, numerous implantable materials have becomes available to aid the surgeon in recreating the abdominal wall. This spectrum of implants includes permanent synthetic meshes, absorbable meshes, composite meshes and biomaterials. This review includes the pros and cons for the commercially available abdominal wall implants as well as a review of the literature regarding outcomes for each material. This review will provide the surgeon with current evidence-based information on implantable abdominal materials to be able to make a more informed decision about which implant to use. PMID:21663579

  4. Genetics Home Reference: abdominal wall defect

    MedlinePlus

    ... size and can usually be diagnosed early in fetal development, typically between the tenth and fourteenth weeks of ... organs at the abdominal wall opening late in fetal development may also contribute to organ injury. Intestinal damage ...

  5. Large Abdominal Wall Endometrioma Following Laparoscopic Hysterectomy

    PubMed Central

    Borncamp, Erik; Mehaffey, Philip; Rotman, Carlos

    2011-01-01

    Background: Endometriosis is a common condition in women that affects up to 45% of patients in the reproductive age group by causing pelvic pain. It is characterized by the presence of endometrial tissue outside the uterine cavity and is rarely found subcutaneously or in abdominal incisions, causing it to be overlooked in patients with abdominal pain. Methods: A 45-year-old woman presented with lower abdominal pain 2 years following a laparoscopic supracervical hysterectomy. She was found to have incidental cholelithiasis and a large abdominal mass suggestive of a significant ventral hernia on CT scan. Results: Due to the peculiar presentation, surgical intervention took place that revealed a large 9cm×7.6cm×6.2cm abdominal wall endometrioma. Conclusion: Although extrapelvic endometriosis is rare, it should be entertained in the differential diagnosis for the female patient who presents with an abdominal mass and pain and has a previous surgical history. PMID:21902990

  6. Bioprosthetic Mesh in Abdominal Wall Reconstruction

    PubMed Central

    Baumann, Donald P.; Butler, Charles E.

    2012-01-01

    Mesh materials have undergone a considerable evolution over the last several decades. There has been enhancement of biomechanical properties, improvement in manufacturing processes, and development of antiadhesive laminate synthetic meshes. The evolution of bioprosthetic mesh materials has markedly changed our indications and methods for complex abdominal wall reconstruction. The authors review the optimal properties of bioprosthetic mesh materials, their evolution over time, and their indications for use. The techniques to optimize outcomes are described using bioprosthetic mesh for complex abdominal wall reconstruction. Bioprosthetic mesh materials clearly have certain advantages over other implantable mesh materials in select indications. Appropriate patient selection and surgical technique are critical to the successful use of bioprosthetic materials for abdominal wall repair. PMID:23372454

  7. 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

  8. Abdominal wall herniae and their underlying pathology

    PubMed Central

    Upchurch, Emma; Al-Akash, Musallam

    2016-01-01

    We describe a case of pseudomyxoma peritonei presenting as a strangulated inguinal hernia. We review the current literature regarding the incidence of underlying pathology in patients presenting with abdominal wall herniae and discuss the need for histological assessment of the hernia sac in selected patients. We highlight the importance of assessing for and being aware of significant underlying pathology in certain patients. PMID:26855074

  9. Laparoscopic excision of abdominal wall desmoid tumor.

    PubMed

    Meshikhes, Abdul-Wahed; Al-Zahrani, Hana; Ewies, Tarek

    2016-02-01

    Open surgical resection is the mainstay treatment for desmoid tumors. Laparoscopic resection is rarely used and not well described in the literature. We report a case of a single, 35-year-old woman who presented with palpable abdominal wall desmoid tumor. The patient had had laparoscopic cholecystectomy 2 years earlier, and the tumor was at the insertion site of the right upper quadrant trocar. The diagnosis was made by a Tru-Cut biopsy at another institution, after the lesion had increased in size and caused increased discomfort. The patient underwent successful laparoscopic resection of the tumor. This report aimed to promote laparoscopic resection of abdominal wall desmoid tumors, whenever feasible, and describe the laparoscopic technique. We believe this is the second case of laparoscopic excision of desmoid tumor reported in the English-language literature. PMID:26781534

  10. ADULT ABDOMINAL WALL HERNIA IN IBADAN

    PubMed Central

    Ayandipo, O.O; Afuwape, O.O; Irabor, D.O; Abdurrazzaaq, A.I.

    2015-01-01

    Background: Abdominal wall hernias are very common diseases encountered in surgical practice. Groin hernia is the commonest type of abdominal wall hernias. There are several methods of hernia repair but tension-free repair (usually with mesh) offers the least recurrent rate. Aim: To describe the clinical profile of anterior abdominal wall hernias and our experience in the surgical management of identified hernias Method: The project was a retrospective study of all patients with abdominal wall hernia presenting into surgical divisions of University College Hospital Ibadan during a 6 year period (January 2008 to December 2013). Relevant information was retrieved from their case notes and analysed. Results: The case records of 1215 (84.7%) patients out of 1435 were retrieved. Elective surgery was done in 981(80.7%) patients while 234 (19.3%) patients had emergency surgery. There were 922 (84.8%) groin hernias and post-operative incisional hernia accounted for 9.1% (111) of the patients. About half (49.1%) of those with incisional hernia were post obstetric and gynaecologic procedure followed by post laparotomy incisional hernias 16 (14%) and others (23.5%). The ratio of inguinal hernia to other types in this study is 3:1. Hollow viscus resection and emergency surgery were predictors of wound infection statistically significant in predicting wound infection (P < 0.001). Peri-operative morbidity/mortality at 28 days post operation was documented in 113 patients (12.1%). One year recurrence rate of groin hernia was 2.1%. Conclusion: The pattern of presentation and management of anterior wall hernias are still the same compared with the earlier study in this hospital. New modality of treatment should be adopted as the standard choice of care. Abdominal wall hernias are very common clinical presentation. Modified Bassini repair was the preferred method of repair due to its simplicity. Mesh repair is becoming more common in recent time but high cost and initial non

  11. Splenic trauma during abdominal wall liposuction: a case report

    PubMed Central

    Harnett, Paul; Koak, Yashwant; Baker, Daryl

    2008-01-01

    Summary A 35-year-old woman collapsed 18 hours after undergoing abdominal wall liposuction. Abdominal CT scan revealed a punctured spleen. She underwent an emergency splenectomy and made an uneventful recovery. PMID:18387911

  12. [Endometriosis in the abdominal wall (author's transl)].

    PubMed

    Caligaris, P; Masselot, R; Ducassou, M J; Le Treut, Y; Bricot, R

    1981-01-01

    The authors give 9 case histories of endometriosis localised to the abdominal wall : 3 of them in the umbilicus, 3 in laparotomy incisions (2 of those were Caesareans), 2 of them in the round ligaments at the external opening of the inguinal canal and 1 of them in the right rectus muscle sheath in the abdomen. The functional symptomatology is rhythmical according to menstruation; it is associated with a burning type of pain, a tumour and blood loss. Over and above the theories of aetiology that are now classical, namely tubal retrograde spill, and lymphatic or venous spread, it would seem that prostaglandins and in particular the ratio of P.G.E. divided by P.D.F2 alpha can play a big role. Although Danazol is an effective treatment for endometriosis, the treatment of choice is, in these lesions that are superficial in localisation and easily accessible, to cut them out surgically. This makes it possible on the one hand to look for other intra-abdominal lesions and also on the other hand to confirm the anatomy and pathology (this was done in 7 out of 9 of our cases). PMID:6459361

  13. Radiofrequency ablation of abdominal wall endometrioma.

    PubMed

    Carrafiello, Gianpaolo; Fontana, Federico; Pellegrino, Carlo; Mangini, Monica; Cabrini, Luca; Mariani, Davide; Piacentino, Filippo; Cuffari, Salvatore; Laganà, Domenico; Fugazzola, Carlo

    2009-11-01

    Extraperitoneal endometriosis is the presence of ectopic, functional endometrium outside the peritoneal cavity, and its occurrence is exceedingly rare. Diagnostic imaging--including ultrasound, duplex ultrasonography, and magnetic resonance imaging--in the preoperative assessment of patients with suspected abdominal wall endometriosis (AWE) is helpful for detection and accurate determination of the extent of disease. The treatment of choice for AWE is surgical excision. In addition, medical therapies can be used. We present one case of AWE treated with percutaneous radiofrequency ablation under ultrasound guidance. There were no major complications, and the patient's symptoms improved. In selected patients, radiofrequency ablation can be used safely for the treatment of AWE; however, further studies are needed to confirm this hypothesis. PMID:19184197

  14. Methods for abdominal respiratory motion tracking.

    PubMed

    Spinczyk, Dominik; Karwan, Adam; Copik, Marcin

    2014-01-01

    Non-invasive surface registration methods have been developed to register and track breathing motions in a patient's abdomen and thorax. We evaluated several different registration methods, including marker tracking using a stereo camera, chessboard image projection, and abdominal point clouds. Our point cloud approach was based on a time-of-flight (ToF) sensor that tracked the abdominal surface. We tested different respiratory phases using additional markers as landmarks for the extension of the non-rigid Iterative Closest Point (ICP) algorithm to improve the matching of irregular meshes. Four variants for retrieving the correspondence data were implemented and compared. Our evaluation involved 9 healthy individuals (3 females and 6 males) with point clouds captured in opposite breathing phases (i.e., inhalation and exhalation). We measured three factors: surface distance, correspondence distance, and marker error. To evaluate different methods for computing the correspondence measurements, we defined the number of correspondences for every target point and the average correspondence assignment error of the points nearest the markers. PMID:24720494

  15. A New Rat Model for Orthotopic Abdominal Wall Allotransplantation

    PubMed Central

    Lao, William W.; Wang, Yen-Ling; Ramirez, Alejandro E.; Cheng, Hui-Yun

    2014-01-01

    Background: Abdominal wall, one of the most commonly transplanted composite tissues, is less researched and lacking animal models. Its clinical necessities were emphasized in multiple case series to reconstruct large abdominal defects. Previous animal models have only studied components of the abdominal wall transplant. We describe findings from a new model that more likely reflect clinical transplantation. Methods: Full-thickness hemiabdominal wall flap was procured from Brown Norway (BN) rats and transplanted to an orthotopic defect on Lewis rats. Three groups were studied: group 1: Lewis to Lewis syngeneic; group 2: BN to Lewis control; and group 3: BN to Lewis with postoperative cyclosporine. Vascular imaging and cross vessel section were performed along with full-thickness abdominal wall. Immune cell profiling with flow cytometry at different time points was studied in all groups. Results: Syngeneic group had no rejection. Control group consistently showed rejection around postoperative day 6. With cyclosporine treatment, however, transplant and recipient tissue integration was observed. Flow cytometry revealed that innate immunity is responsible for the initial inflammatory events following abdominal wall engraftment. Adaptive immunity cells, specifically interferon-γ-producing T helper (Th) 1 and interleukin-17-producing Th17 cells, dramatically and positively correlate with rejection progression of abdominal wall transplants. Conclusions: Technical, histological, and immunological aspects of a new rat model are described. These results give clues to what occurs in human abdominal wall transplantation. In addition, Th1, a proinflammatory cell, was found to be a potential biomarker for allograft rejection. PMID:25289329

  16. [Laparoscopic repair of abdominal wall hernias].

    PubMed

    Bezsilla, János

    2010-10-01

    Repair of abdominal wall defects is a challenge for all general surgeons and a variety of methods have been described in the past. Traditionally, primary suture repair was shown to have a high recurrence rate in long-term follow-up studies. Herniorrhaphies that apply a large prosthetic mesh are appear to have a lower failure rate, but extensive dissection of soft tissue contributes to an increased incidence of wound infections and wound-related complications. The method of laparoscopic incisional hernia repair was developed in the early 1990s. This technique is based on the same physical and surgical principles as the open underlay procedure. The laparoscopic intraperitoneal onlay mesh (IPOM) technique and mesh materials were developed further in subsequent years, and there have been numerous reports on successful use of the IPOM technique even for extremely large hernia openings in obese and elderly patients. Reduced surgical trauma and lower infection and recurrence rates are key advantages of the minimally invasive repair. Therefore, this operation has increased in popularity promising shorter hospital stay, improved outcome, and fewer complications than traditional open procedures. PMID:20965866

  17. Practical Approaches to Definitive Reconstruction of Complex Abdominal Wall Defects.

    PubMed

    Latifi, Rifat

    2016-04-01

    With advances in abdominal surgery and the management of major trauma, complex abdominal wall defects have become the new surgical disease, and the need for abdominal wall reconstruction has increased dramatically. Subsequently, how to reconstruct these large defects has become a new surgical question. While most surgeons use native abdominal wall whenever possible, evidence suggests that synthetic or biologic mesh needs to be added to large ventral hernia repairs. One particular group of patients who exemplify "complex" are those with contaminated wounds, enterocutaneous fistulas, enteroatmospheric fistulas, and/or stoma(s), where synthetic mesh is to be avoided if at all possible. Most recently, biologic mesh has become the new standard in high-risk patients with contaminated and dirty-infected wounds. While biologic mesh is the most common tissue engineered used in this field of surgery, level I evidence is needed on its indication and long-term outcomes. Various techniques for reconstructing the abdominal wall have been described, however the long-term outcomes for most of these studies, are rarely reported. In this article, I outline current practical approaches to perioperative management and definitive abdominal reconstruction in patients with complex abdominal wall defects, with or without fistulas, as well as those who have lost abdominal domain. PMID:26585951

  18. Case report: Leiomyoma of the anterior abdominal wall.

    PubMed

    Ernest Ong, C W; Siow, S L

    2016-04-01

    Leiomyomas are benign soft tissue swellings of smooth muscle origin, most commonly found in the uterus. Extra uterine leiomyomas presenting as an abdominal mass is often a diagnostic challenge as such occurrence is rare. We present a rare case of primary abdominal wall leiomyoma, and highlight the importance of laparoscopic approach in the diagnosis and treatment of such tumour. PMID:27326950

  19. Prosthetics and Techniques in Repair of Animal's Abdominal Wall.

    PubMed

    Karrouf, Gamal; Zaghloul, Adel; Abou-Alsaud, Mohamed; Barbour, Elie; Abouelnasr, Khaled

    2016-01-01

    The management of abdominal wall repair continues to present a challenging problem, especially in the repair of major defects. Many abdominal wall defects can be repaired by primary closure; however, if the defect is large and there is a tension on the closure of the wound, the use of prosthetic materials becomes indispensable. Many studies have been performed with various materials and implant techniques, without the comparison of their degrees of success, based on sound meta-analysis and/or inclusive epidemiologic studies. This review covered the effectiveness of recent advances in prosthetic materials and implant procedures used in repair of abdominal wall, based on biomechanical properties and economic aspects of reconstructed large abdominal wall defects and hernias in animals. The presented results in this review helped to reach treatment algorithms that could maximize outcomes and minimize morbidity. PMID:27293982

  20. Prosthetics and Techniques in Repair of Animal's Abdominal Wall

    PubMed Central

    Karrouf, Gamal; Zaghloul, Adel; Abou-Alsaud, Mohamed; Barbour, Elie; Abouelnasr, Khaled

    2016-01-01

    The management of abdominal wall repair continues to present a challenging problem, especially in the repair of major defects. Many abdominal wall defects can be repaired by primary closure; however, if the defect is large and there is a tension on the closure of the wound, the use of prosthetic materials becomes indispensable. Many studies have been performed with various materials and implant techniques, without the comparison of their degrees of success, based on sound meta-analysis and/or inclusive epidemiologic studies. This review covered the effectiveness of recent advances in prosthetic materials and implant procedures used in repair of abdominal wall, based on biomechanical properties and economic aspects of reconstructed large abdominal wall defects and hernias in animals. The presented results in this review helped to reach treatment algorithms that could maximize outcomes and minimize morbidity. PMID:27293982

  1. Abdominal Wall Endometrioma after Laparoscopic Operation of Uterine Endometriosis.

    PubMed

    Vukšić, Tihomir; Rastović, Pejana; Dragišić, Vedran

    2016-01-01

    Endometriosis is presence of functional endometrium outside of uterine cavum. As a pluripotent tissue, endometrium has the possibility of implanting itself almost everywhere; even implantation in abdominal wall was described, but it is not common site. This case report presents implantation of functional endometrium in abdominal wall, inside scar tissue, and after insertion of a laparoscopic trocar port. Final diagnosis was confirmed by pathohistological examination. PMID:27340586

  2. Abdominal Wall Endometrioma after Laparoscopic Operation of Uterine Endometriosis

    PubMed Central

    Vukšić, Tihomir; Rastović, Pejana; Dragišić, Vedran

    2016-01-01

    Endometriosis is presence of functional endometrium outside of uterine cavum. As a pluripotent tissue, endometrium has the possibility of implanting itself almost everywhere; even implantation in abdominal wall was described, but it is not common site. This case report presents implantation of functional endometrium in abdominal wall, inside scar tissue, and after insertion of a laparoscopic trocar port. Final diagnosis was confirmed by pathohistological examination. PMID:27340586

  3. [Abdominal wall closure by incisional hernia and herniation after laparostoma].

    PubMed

    Mischinger, H-J; Kornprat, P; Werkgartner, G; El Shabrawi, A; Spendel, S

    2010-03-01

    As hernias and abdominal wall defects have a variety of etiologies each with its own complications and comorbidities in various constellations, efficient treatment requires patient-oriented management. There is no recommended standard treatment and the very different clinical pictures demand an individualized interdisciplinary approach. Particularly in the case of complicated hernias, the planning of the operation should focus on the problems posed by the individual patient. Treatment mainly depends on the etiology of the hernia, immediate or long-term complications and the efficiency of individual repair techniques. Abdominal wall repair for recurrent herniation requires direct closure of the fascia generally using the sublay technique with a lightweight mesh. It is still unclear whether persistent inflammation, mesh dislocation, fistula formation or other long-term complications are due to certain materials or to the surgical technique. With mesh infections it has been shown to be advantageous to remove a polytetrafluoroethylene (PTFE) mesh, while the combination of systemic and local treatment appears to suffice for a polypropylene or polyester mesh. Heavier meshes in the sublay position or plastic reconstruction with autologous tissue are indicated as substitutes for the abdominal wall for giant hernias, repeated recurrences and large abdominal wall defects. A laparostoma is increasingly more often created to treat septic intra-abdominal processes but is very often responsible for a complicated hernia. If primary repair of the abdominal wall is not an option, resorbable material or split skin is used for coverage under the auspices of a planned hernia repair. PMID:20145901

  4. A Traumatic Abdominal Wall Hernia Repair: A Laparoscopic Approach

    PubMed Central

    Wilson, Kenneth L.; Rosser, James C.

    2012-01-01

    Background: Traumatic abdominal wall hernias from blunt trauma usually occur as a consequence of motor vehicle collisions where the force is tangential, sudden, and severe. Although rare, these hernias can go undetected due to preservation of the skin overlying the hernia defect. Open repairs can be challenging and unsuccessful due to avulsion of muscle directly from the iliac crest, with or without bone loss. A laparoscopic approach to traumatic abdominal wall hernia can aid in the delineation of the hernia and allow for a safe and effective repair. Case Description: A 36-year-old female was admitted to our Level 1 trauma center with a traumatic abdominal wall hernia located in the right flank near the iliac crest after being involved in a high-impact motor vehicle collision. Computed tomography and magnetic resonance imaging of the abdomen revealed the presence of an abdominal wall defect that was unapparent on physical examination. The traumatic abdominal wall hernia in the right flank was successfully repaired laparoscopically. One-year follow-up has shown no sign of recurrence. Discussion: A traumatic abdominal wall hernia rarely presents following blunt trauma, but should be suspected following a high-impact motor vehicle collision. Frequently, repair is complicated by the need to have fixation of mesh to bony landmarks (eg, iliac crest). In spite of this challenge, the laparoscopic approach with tension-free mesh repair of a traumatic abdominal wall hernia can be accomplished successfully using an approach similar to that taken for laparoscopic inguinal hernia repair. PMID:23477181

  5. Personalized identification of abdominal wall hernia meshes on computed tomography.

    PubMed

    Pham, Tuan D; Le, Dinh T P; Xu, Jinwei; Nguyen, Duc T; Martindale, Robert G; Deveney, Clifford W

    2014-01-01

    An abdominal wall hernia is a protrusion of the intestine through an opening or area of weakness in the abdominal wall. Correct pre-operative identification of abdominal wall hernia meshes could help surgeons adjust the surgical plan to meet the expected difficulty and morbidity of operating through or removing the previous mesh. First, we present herein for the first time the application of image analysis for automated identification of hernia meshes. Second, we discuss the novel development of a new entropy-based image texture feature using geostatistics and indicator kriging. Third, we seek to enhance the hernia mesh identification by combining the new texture feature with the gray-level co-occurrence matrix feature of the image. The two features can characterize complementary information of anatomic details of the abdominal hernia wall and its mesh on computed tomography. Experimental results have demonstrated the effectiveness of the proposed study. The new computational tool has potential for personalized mesh identification which can assist surgeons in the diagnosis and repair of complex abdominal wall hernias. PMID:24184112

  6. WSES guidelines for emergency repair of complicated abdominal wall hernias

    PubMed Central

    2013-01-01

    Emergency repair of complicated abdominal hernias is associated with poor prognosis and a high rate of post-operative complications. A World Society of Emergency Surgery (WSES) Consensus Conference was held in Bergamo in July 2013, during the 2nd Congress of the World Society of Emergency Surgery with the goal of defining recommendations for emergency repair of abdominal wall hernias in adults. This document represents the executive summary of the consensus conference approved by a WSES expert panel. PMID:24289453

  7. Improving the Efficiency of Abdominal Aortic Aneurysm Wall Stress Computations

    PubMed Central

    Zelaya, Jaime E.; Goenezen, Sevan; Dargon, Phong T.; Azarbal, Amir-Farzin; Rugonyi, Sandra

    2014-01-01

    An abdominal aortic aneurysm is a pathological dilation of the abdominal aorta, which carries a high mortality rate if ruptured. The most commonly used surrogate marker of rupture risk is the maximal transverse diameter of the aneurysm. More recent studies suggest that wall stress from models of patient-specific aneurysm geometries extracted, for instance, from computed tomography images may be a more accurate predictor of rupture risk and an important factor in AAA size progression. However, quantification of wall stress is typically computationally intensive and time-consuming, mainly due to the nonlinear mechanical behavior of the abdominal aortic aneurysm walls. These difficulties have limited the potential of computational models in clinical practice. To facilitate computation of wall stresses, we propose to use a linear approach that ensures equilibrium of wall stresses in the aneurysms. This proposed linear model approach is easy to implement and eliminates the burden of nonlinear computations. To assess the accuracy of our proposed approach to compute wall stresses, results from idealized and patient-specific model simulations were compared to those obtained using conventional approaches and to those of a hypothetical, reference abdominal aortic aneurysm model. For the reference model, wall mechanical properties and the initial unloaded and unstressed configuration were assumed to be known, and the resulting wall stresses were used as reference for comparison. Our proposed linear approach accurately approximates wall stresses for varying model geometries and wall material properties. Our findings suggest that the proposed linear approach could be used as an effective, efficient, easy-to-use clinical tool to estimate patient-specific wall stresses. PMID:25007052

  8. Management of the Sequelae of Severe Congenital Abdominal Wall Defects

    PubMed Central

    Marti, Eunate; Delgado, Maria-Dolores; Gomez, Andres

    2016-01-01

    Background The survival rate of newborns with severe congenital abdominal wall defects has increased. After successfully addressing life-threatening complications, it is necessary to focus on the cosmetic and functional outcomes of the abdominal wall. Methods We performed a chart review of five cases treated in our institution. Results Five patients, ranging from seven to 18 years of age, underwent the following surgical approaches: simple approximation of the rectus abdominis fascia, the rectus abdominis sheath turnover flap, the placement of submuscular tissue expanders, mesh repair, or a combination of these techniques depending on the characteristics of each individual case. Conclusions Patients with severe congenital abdominal wall defects require individualized surgical treatment to address both the aesthetic and functional issues related to the sequelae of their defects. PMID:27218024

  9. [BIOLOGICAL IMPLANTS IN ABDOMINAL WALL HERNIA REPAIR (REVIEW)].

    PubMed

    Abatov, N; Badyrov, R; Abatova, A; Assamidanov, E; Kaukenov, B

    2016-02-01

    The use of synthetic meshes as a material for abdominal wall hernia repair does not always ensure a recurrence-free treatment outcome and full recovery of the abdominal wall functional activity. There are well-known disadvantages such as poor resistance to infection, the infiltrate formation in the place of implantation, expressed adhesive process in cases of introperitoneal fixation, to create certain restrictions on the using of these implants for abdominal wall reconstruction. The search for alternative materials that could minimize the risk of complications, has led to the study of biological grafts. It is known that various methods for the manufacturing biological implants determine endogenous properties for each material separately, and may be cause a variety of biological responses in vivo after implantation. The question has not been resolved, what the fresh raw material is better to use for derive biological implants. In this review we investigated the interaction of different types of biological implants between the abdominal wall and the organs of abdominal cavity of the recipient, their ability to resist infection and the development of relapses, as a leading indicator of the effectiveness of hernioplasty. PMID:27001778

  10. Ultrasonography and computed tomography of inflammatory abdominal wall lesions

    SciTech Connect

    Yeh, H.C.; Rabinowitz, J.G.

    1982-09-01

    Twenty-four patients with inflammatory lesions of the abdominal wall were examined by ultrasonography. Nine of these patients underwent computed tomographic (CT) scanning as well. Both ultrasonography and CT clearly delineated the exact location and extent of abdominal wall abscesses. Abscesses were easily differentiated from cellulitis or phlegmon with ultrasound. The peritoneal line was more clearly delineated on ultrasonograms than on CT scans; abscesses were also more distinct on the ultrasonograms because of their low echogenicity compared with the surrounding structures. Gas bubbles, fat density with specific low attenuation values, and underlying inflamed bowel loops in obese patients with Crohn's disease were better delineated by CT.

  11. [Extraskeletal mesenchymal chondrosarcoma of lateral abdominal wall (case report)].

    PubMed

    Akfirat, Murat; Kayaoğlu, Hüseyin Ayhan

    2004-12-01

    Mesenchymal chondrosarcomas are very rare in comparison to the conventional types. They can occur from any location containing mesenchymal cells, but most arise in the lower extremities, leptomeninges and in the orbits. Other sites are very uncommon. We present a case of mesenchymal chondrosarcoma of the lateral abdominal wall, and this is the first report of the tumor localized in this region. PMID:15611919

  12. Malignant Schwannoma of Anterior Abdominal Wall: Report of a Case

    PubMed Central

    Khorgami, Zhamak; Nasiri, Shirzad; Rezakhanlu, Freshteh; Sodagari, Nassim

    2009-01-01

    Malignant schwannoma of the anterior abdominal wall nerves is extremely rare. Malignant peripheral nerve sheath tumors (MPNST) represent approximately 10% of all soft tissue sarcomas and it is found in 4% of patients with neurofibromatosis 1. We present a case of malignant schwannoma in a 28-year-old female patient with neurofibromatosis 1. She presented with a painful mass in the right upper quadrant of her abdomen. The tumor location was in the abdominal wall in explorative laparatomy and malignant schwannoma was diagnosed in pathologic assessment. The tumor recurred in 3 months and computed tomography showed two masses in the right side of abdominopelvic cavity. Thereafter, second complete surgical resection was performed and pathologic finding was the same. In spite of administering chemotherapy after second surgery,the tumor recurred and magnetic resonance imaging finding showed a huge heterogeneously enhancing mass with adhesion to the inner side of the abdominal wall. The patient died because of acute respiratory failure due to multiple bilateral pulmonary metastases. Tumor location and rapid recurrence was unique in our patient. Keywords Malignant peripheral nerve sheath tumor; Malignant schwannoma; Abdominal wall PMID:22461875

  13. Which mesh or graft? Prosthetic devices for abdominal wall reconstruction.

    PubMed

    Abid, Shazia; El-Hayek, Kevin

    2016-03-01

    This article reviews the ever-increasing number of prosthetic devices--both synthetic mesh and biologic grafts--now in use for abdominal wall reconstruction. It also introduces a novel hybrid synthetic/biologic graft (Zenapro) and suture passer device (Novapass). PMID:26961445

  14. [Controversies in the current management of traumatic abdominal wall hernias].

    PubMed

    Moreno-Egea, Alfredo; Girela, Enrique; Parlorio, Elena; Aguayo-Albasini, José Luis

    2007-11-01

    The management of traumatic abdominal wall hernias is controversial. We performed a MEDLINE search and report a personal series of 10 patients. Cases were classified according to the cause of injury. Fifty-six percent were caused by car accidents and 14% by bicycle accidents. Diagnosis was clinical in 22% and surgical in 13% and intra-abdominal lesions were found in 67%. Treatment was delayed in 12%. In our series, 55% were lumbar hernias due to traffic accidents and all were associated with pelvic fracture. Treatment was delayed in 50%, including laparoscopic surgery with good results. In conclusion, traumatic hernias due to road traffic accidents are frequently associated with intra-abdominal lesions. The diagnostic technique of choice is computed tomography and delayed surgery (laparoscopy) is an effective option. PMID:18021624

  15. Quantitative anatomical labeling of the anterior abdominal wall

    NASA Astrophysics Data System (ADS)

    Allen, Wade M.; Xu, Zhoubing; Asman, Andrew J.; Poulose, Benjamin K.; Landman, Bennett A.

    2013-03-01

    Ventral hernias (VHs) are abnormal openings in the anterior abdominal wall that are common side effects of surgical intervention. Repair of VHs is the most commonly performed procedure by general surgeons worldwide, but VH repair outcomes are not particularly encouraging (with recurrence rates up to 43%). A variety of open and laparoscopic techniques are available for hernia repair, and the specific technique used is ultimately driven by surgeon preference and experience. Despite routine acquisition of computed tomography (CT) for VH patients, little quantitative information is available on which to guide selection of a particular approach and/or optimize patient-specific treatment. From anecdotal interviews, the success of VH repair procedures correlates with hernia size, location, and involvement of secondary structures. Herein, we propose an image labeling protocol to segment the anterior abdominal area to provide a geometric basis with which to derive biomarkers and evaluate treatment efficacy. Based on routine clinical CT data, we are able to identify inner and outer surfaces of the abdominal walls and the herniated volume. This is the first formal presentation of a protocol to quantify these structures on abdominal CT. The intra- and inter rater reproducibilities of this protocol are evaluated on 4 patients with suspected VH (3 patients were ultimately diagnosed with VH while 1 was not). Mean surfaces distances of less than 2mm were achieved for all structures.

  16. A numerical investigation of the healthy abdominal wall structures.

    PubMed

    Pachera, P; Pavan, P G; Todros, S; Cavinato, C; Fontanella, C G; Natali, A N

    2016-06-14

    The present work aims to assess, via numerical modeling, the global passive mechanical behavior of the healthy abdominal wall under the action of pressures that characterize different daily tasks and physiological functions. The evaluation of a normal range of intra-abdominal pressure (IAP) during activities of daily living is fundamental because pressure alterations can cause several adverse effects. At this purpose, a finite element model is developed from literature histomorphometric data and from diagnostic images of Computed Tomography (CT), detailing the different anatomical regions. Numerical simulations cover an IAP up to the physiological limit of 171 (0.0223MPa) mmHg reached while jumping. Numerical results are in agreement with evidences on physiological abdomens when evaluating the local deformations along the craniocaudal direction, the transversal load forces in different regions and the increase of the abdominal area at a IAP of 12mmHg. The developed model can be upgraded for the investigation of the abdominal hernia repair and the assessment of prostheses mechanical compatibility, correlating stiffness and tensile strength of the abdominal tissues with those of surgical meshes. PMID:27133659

  17. Complex abdominal wall defects: appearances at prenatal imaging.

    PubMed

    Pakdaman, Reza; Woodward, Paula J; Kennedy, Anne

    2015-01-01

    Abdominal wall defects are a complex group of anomalies, and many are incorrectly diagnosed. Evaluation of the defect relative to the umbilical cord insertion site is fundamentally important in differentiating among the various malformations. The two most common abdominal wall defects are gastroschisis, in which the defect is on the right side of the normally inserting cord and free-floating bowel loops are present, and omphalocele, in which the cord inserts on a membrane-covered midline defect. Omphalocele may also form a portion of a more complex defect that may remain undiagnosed without thorough evaluation. In cloacal exstrophy, the defect extends inferiorly and the bowel loops extrude between the two bladder halves. In pentalogy of Cantrell, the defect extends superiorly and is typically associated with ectopia cordis. Bladder exstrophy is a lower abdominal defect in which the hallmark finding is absence of a fluid-filled bladder. The cord insertion site is normal to low but does not form part of the defect. Both body stalk anomaly and abdominoschisis due to amniotic bands cause severe malformations, often involving extrusion of solid organs and the bowel. Although these two entities have many overlapping features, body stalk anomaly may be recognized on the basis of absence of a free-floating umbilical cord. With use of an algorithmic approach beginning with discovery of the location of the defect, a more precise diagnosis can be determined that may directly affect pre- and postnatal management decisions. PMID:25763744

  18. Outcome of abdominal wall hernia repair with Permacol™ biologic mesh.

    PubMed

    Cheng, Amy W; Abbas, Maher A; Tejirian, Talar

    2013-10-01

    The use of biologic mesh in abdominal wall operations has gained popularity despite a paucity of outcome data. We aimed to review the experience of a large healthcare organization with Permacol™. A retrospective study was conducted of patients who underwent abdominal hernia repair with Permacol™ in 14 Southern California hospitals. One hundred ninety-five patients were analyzed over a 4-year period. Operations included ventral/incisional hernia repairs, ostomy closures, parastomal hernia repairs, and inguinal hernia repairs. In 50 per cent of the patients, Permacol™ was used to reinforce a primary fascial repair and in 50 per cent as a fascial bridge. The overall complication rate was 39.5 per cent. The complication rate was higher in patients with infected versus clean wounds, body mass index (BMI) 40 kg/m(2) or greater versus BMI less than 40 kg/m(2), in patients with prior mesh repair, and when mesh was used as a fascial bridge. With a mean follow-up of 2.1 years, morbid obesity was associated with a higher recurrence. To date this is the largest study on the use of Permacol™ in abdominal wall hernia repair. In our patient population undergoing heterogeneous operations with a majority of wounds as Class II or higher, use of Permacol™ did not eliminate wound morbidity or prevent recurrence, especially in morbidly obese patients. PMID:24160785

  19. Abdominal organ motion measured using 4D CT

    SciTech Connect

    Brandner, Edward D.; Wu, Andrew . E-mail: andrew.wu@jefferson.edu; Chen, Hungcheng; Heron, Dwight; Kalnicki, Shalom; Komanduri, Krishna; Gerszten, Kristina; Burton, Steve; Ahmed, Irfan; Shou, Zhenyu

    2006-06-01

    Purpose: To measure respiration-induced abdominal organ motion using four-dimensional computed tomography (4D CT) scanning and to examine the organ paths. Methods and Materials: During 4D CT scanning, consecutive CT images are acquired of the patient at each couch position. Simultaneously, the patient's respiratory pattern is recorded using an external marker block taped to the patient's abdomen. This pattern is used to retrospectively organize the CT images into multiple three-dimensional images, each representing one breathing phase. These images are analyzed to measure organ motion between each phase. The displacement from end expiration is compared to a displacement limit that represents acceptable dosimetric results (5 mm). Results: The organs measured in 13 patients were the liver, spleen, and left and right kidneys. Their average superior to inferior absolute displacements were 1.3 cm for the liver, 1.3 cm for the spleen, 1.1 cm for the left kidney, and 1.3 cm for the right kidney. Although the organ paths varied among patients, 5 mm of superior to inferior displacement from end expiration resulted in less than 5 mm of displacement in the other directions for 41 of 43 organs measured. Conclusions: Four-dimensional CT scanning can accurately measure abdominal organ motion throughout respiration. This information may result in greater organ sparing and planning target volume coverage.

  20. Congenital Anaplastic Rhabdomyosarcoma Presenting As Abdominal Wall Mass

    PubMed Central

    Mondal, Krishnendu; Mandal, Rupali

    2016-01-01

    Rhabdomyosarcoma encompasses a group of malignant myogenic neoplasms expressing a multitude of clinical and pathological diversities. It is the commonest soft tissue sarcoma of childhood but neonates are rarely affected. Embryonal subtype is the most frequent. Head-neck and genitourinary tracts are predominant sites, while trunk is considered among the unusual sites of rhabdomyosarcoma. Herein we report a case of anaplastic rhabdomyosarcoma in a newborn girl presenting, at the Pediatric Surgery Outpatient Department of North Bengal Medical College and Hospital, India in 2013 with a large tumor mass in the left flank region, arising from abdominal wall muscles. PMID:26870149

  1. Necrotizing Fasciitis of the Abdominal Wall Caused by Serratia Marcescens.

    PubMed

    Lakhani, Naheed A; Narsinghani, Umesh; Kumar, Ritu

    2015-04-15

    In this article, we present the first case of necrotizing fasciitis affecting the abdominal wall caused by Serratia marcescens and share results of a focused review of S. marcescens induced necrotizing fasciitis. Our patient underwent aorto-femoral bypass grafting for advanced peripheral vascular disease and presented 3 weeks postoperatively with pain, erythema and discharge from the incision site in the left lower abdominal wall and underwent multiple debridement of the affected area. Pathology of debrided tissue indicated extensive necrosis involving the adipose tissue, fascia and skeletal muscle. Wound cultures were positive for Serratia marcescens. She was successfully treated with antibiotics and multiple surgical debridements. Since necrotizing fasciitis is a medical and surgical emergency, it is critical to examine infectivity trends, clinical characteristics in its causative spectrum. Using PubMed we found 17 published cases of necrotizing fasciitis caused by Serratia marcescens, and then analyzed patterns among those cases. Serratia marcescens is prominent in the community and hospital settings, and information on infection presentations, risk factors, characteristics, treatment, course, and complications as provided through this study can help identify cases earlier and mitigate poor outcomes. Patients with positive blood cultures and those patients where surgical intervention was not provided or delayed had a higher mortality. Surgical intervention is a definite way to establish the diagnosis of necrotizing infection and differentiate it from other entities. PMID:26294949

  2. [Gasless laparoscopic cholecystectomy using retractor of the abdominal wall].

    PubMed

    D'Urbano, C; Fuertes Guiro, F; Sampietro, R

    1996-03-01

    The Authors present a new gasless laparoscopic cholecystectomy method using an abdominal wall elevator with subcutaneous traction ("laparotenser"). Fifty patients between May 1994 and March 1995 were operated by videolaparoscopy using this new gasless method. Twenty of them were operated with Nagai's method while the laparotenser was used in the remaining thirty. The results obtained are similar to those using pneumoperitoneum. It has been observed a global reduction of costs, less postoperative pain, no influence in cardiovascular and metabolic indexes. No complications were reported during the postoperative period but two cases of conversion to laparotomy not related to the method used were needed. Laparoscopic cholecystectomy without pneumoperitoneum using the subcutaneous elevator of the abdominal wall ("laparotenser") has demonstrated that it's possible to operate in a working space similar to that created by the pneumoperitoneum. After an initial period of distrust towards the laparoscopic methods without pneumoperitoneum it has been accepted that gasless methods multiply the indications to minimally invasive surgery in patients with cardiorespiratory problems considered no ideal candidates to laparoscopic cholecystectomy with pneumoperitoneum. PMID:8679422

  3. Abdominal Wall Transplantation: Skin as a Sentinel Marker for Rejection.

    PubMed

    Gerlach, U A; Vrakas, G; Sawitzki, B; Macedo, R; Reddy, S; Friend, P J; Giele, H; Vaidya, A

    2016-06-01

    Abdominal wall transplantation (AWTX) has revolutionized difficult abdominal closure after intestinal transplantation (ITX). More important, the skin of the transplanted abdominal wall (AW) may serve as an immunological tool for differential diagnosis of bowel dysfunction after transplant. Between August 2008 and October 2014, 29 small bowel transplantations were performed in 28 patients (16 male, 12 female; aged 41 ± 13 years). Two groups were identified: the solid organ transplant (SOT) group (n = 15; 12 ITX and 3 modified multivisceral transplantation [MMVTX]) and the SOT-AWTX group (n = 14; 12 ITX and 2 MMVTX), with the latter including one ITX-AWTX retransplantation. Two doses of alemtuzumab were used for induction (30 mg, 6 and 24 h after reperfusion), and tacrolimus (trough levels 8-12 ng/mL) was used for maintenance immunosuppression. Patient survival was similar in both groups (67% vs. 61%); however, the SOT-AWTX group showed faster posttransplant recovery, better intestinal graft survival (79% vs. 60%), a lower intestinal rejection rate (7% vs. 27%) and a lower rate of misdiagnoses in which viral infection was mistaken and treated as rejection (14% vs. 33%). The skin component of the AW may serve as an immune modulator and sentinel marker for immunological activity in the host. This can be a vital tool for timely prevention of intestinal graft rejection and, more important, avoidance of overimmunosuppression in cases of bowel dysfunction not related to graft rejection. PMID:26713513

  4. [Diagnostic difficulty of abdominal wall endometrioma: clinical case and literature review].

    PubMed

    Martínez, Denzil Garteiz; Romano, Rafael Carbo; Sánchez, Alejandro Weber; Horcasitas, Lourdes Molinar

    2008-02-01

    Abdominal wall endometrioma is a rare clinical condition with which the general surgeon is faced and usually presents a diagnostic challenge due to the similar signs and symptoms that this illness shares with other tumors of the abdominal wall. A clinical case which exemplifies this diagnostic challenge is presented, and a review is made about the physiopathology, diagnosis and treatment of abdominal wall endometriomas, emphasizing on the different diagnoses with which it can be confused. PMID:18798406

  5. Use of synthetic mesh for the entire abdominal wall after TRAM flap transfer.

    PubMed

    Moscona, R A; Ramon, Y; Toledano, H; Barzilay, G

    1998-03-01

    Abdominal wall competence is a major concern of all plastic surgeons using the TRAM flap for breast reconstruction. Low hernia rates and adequate abdominal stability are standard expectations in abdominal wall closure. Described here is this institution's experience with the use of a large piece of synthetic mesh as a supplementary reinforcement for the entire abdominal wall in an attempt to stabilize it and achieve a superior abdominal aesthetic result. Twenty-five consecutive patients had routine reinforcement with the extended mesh technique. Mean patient follow-up was 24 months with a minimum of 1 year. No hernia or mesh-related infection were encountered and only one patient had a lower abdominal bulge. We recommend the use of a large synthetic mesh for improved strength and aesthetic quality of the abdominal wall after TRAM flap breast reconstruction. PMID:9500387

  6. An arterial wall motion test phantom for the evaluation of wall motion software.

    PubMed

    Hammer, Steven J; Dineley, Judith; Easson, William J; Hoskins, Peter R

    2007-09-01

    Increasing cardiovascular disease has led to new ultrasound methods of assessing artery disease such as arterial wall motion measurement. To validate arterial wall motion software, we developed a mechanically-controlled wall motion test phantom with straight upper and lower agar tissue mimicking material layers that resemble an artery cross section. The wall separation, displacements and wall velocities and accelerations can be controlled within physiologically realistic levels. A user-definable displacement or one of several pre-defined displacement waveforms can be created by the user with custom-written software. The test phantom is then controlled using the defined waveform with a stepper motor controller. Accuracy assessment of the test phantom with a laser vibrometer yielded a positional accuracy of 36+/-2 microm. A typical application of the test phantom is demonstrated by assessing a tissue Doppler imaging (TDI) method for estimating the distension waveform. The TDI-based method was found to have a minimum resolvable displacement of 22.5 microm, and a measurement accuracy of +/-8% using a physiological wall motion movement with a peak displacement of 689 microm. The accuracy of the TDI method was found to decrease with decreasing wall displacement and increasing wall velocity. PMID:17587485

  7. Athletic injuries of the lateral abdominal wall: review of anatomy and MR imaging appearance.

    PubMed

    Stensby, J Derek; Baker, Jonathan C; Fox, Michael G

    2016-02-01

    The lateral abdominal wall is comprised of three muscles, each with a different function and orientation. The transversus abdominus, internal oblique, and external oblique muscles span the abdominal cavity between the iliocostalis lumborum and quadratus lumborum posteriorly and the rectus abdominis anteriorly. The lateral abdominal wall is bound superiorly by the lower ribs and costal cartilages and inferiorly by the iliac crest and inguinal ligament. The lateral abdominal wall may be acutely or chronically injured in a variety of athletic endeavors, with occasional acute injuries in the setting of high-energy trauma such as motor vehicle collisions. Injuries to the lateral abdominal wall may result in lumbar hernia formation, unique for its high incarceration rate, and also Spigelian hernias. This article will review the anatomy, the magnetic resonance (MR) imaging approach, and the features and complications of lateral abdominal wall injuries. PMID:26450606

  8. Abdominal Wall Endometrioma: Ultrasonographic Features and Correlation with Clinical Findings

    PubMed Central

    Solak, Aynur; Genç, Berhan; Yalaz, Seyhan; Şahin, Neslin; Sezer, Taylan Özgür; Solak, İlhami

    2013-01-01

    Background: The diagnosis of abdominal wall endometrioma (AWE) is often confused with other surgical conditions. Certain factors relating to knowledge of the clinical history of the disease make correct diagnosis and treatment difficult. Aims: To present the clinical findings and ultrasonographic (US) features of AWE with special emphasis on size-related features. Study Design: This study reviewed abdominal wall endometriomas during a 2-year period in the Radiology Department of Sifa University Hospital, Izmir. Methods: Eleven women (mean age 32.6 years) with 12 scar endometriomas (mean diameter 29.2 mm) were consecutively evaluated by US and Colour Doppler examination (CDUS) prior to surgery. Lesions were grouped into large (≥3 cm) and small nodules. Vascularisation was classified as location (central, peripheral and mixed) and severity (absent, moderately vascular and hypervascular). In each patient, the nature of pain (absent, cyclic: associated with menstruation and continuous), historical and clinical data were documented. Four patients underwent Magnetic Resonance Imaging and their findings were presented. Fisher’s exact test, χ2 test for categorical data and the unpaired T-test for continuous variables were used for statistical analysis. Results: In all the women, US of the AWE showed the presence of a solid hypoechoic mass (less echogenic than the surrounding hyperechoic fat) within the abdominal wall. There was a significant correlation between AWE sizes with repeated caesareans and the mean time between the last operation and admission to hospital (p<0.05). Large endometriomas showed increased central vascularity (p<0.05). Cyclic pain was more frequent in small lesions, whereas continuous pain was more commonly found in patients with larger lesions (p<0.05). Conclusion: AWE is often misdiagnosed clinically because endometriosis may occur years after the caesarean section, the pain is often non-cyclic in nature, and there is not always a palpable

  9. [Training of residents in abdominal wall surgery in Spain].

    PubMed

    Miguelena Bobadilla, J M; Morales García, D; Serra Aracil, X; Sanz Sánchez, M; Iturburu, I; Docobo Durántez, F; Jover Navalón, J M; López De Cenarruzabeitia, I; Lobo Martínez, E

    2013-02-01

    The training of residents in abdominal wall surgery is a fundamental aspect of surgical training, representing globally 20% of its activity. In this paper, we analyze the current state of resident training in this kind of surgery in Spain, taking into account the broad spectrum it covers: general services, specific functional units, ambulatory surgery programs. To do this, based on the specifications of the specialty program, specific data were used from several different sources of direct information and a review of the results obtained by residents in hernia surgery. In general, our residents agree with their training and the recorded results are in line with objectives outlined in the program. However, it would be important to structure their teaching schedules, a rotation period in any specific unit and their involvement in outpatient surgery programs. PMID:22074730

  10. Resection and Abdominal Wall Reconstruction of a Desmoid Tumor with Endometrioma Features

    PubMed Central

    Majors, Jaqueline; Stoikes, Nathaniel F.; Nejati, Reza

    2016-01-01

    Desmoid tumors are rare, musculoaponeurotic mesenchymal origin tumors arising from the proliferation of well-differentiated fibroblasts. Desmoid tumors may arise from any location with the abdominal cavity, abdominal wall and extremity locations being most frequent. We present the case of a 35-year-old female with a history of endometriosis who presented palpable abdominal mass and cyclic abdominal pain. Resection was performed for a presumed desmoid soft tissue tumor. Final pathology demonstrated desmoid histology admixed with abdominal wall endometriosis (endometrioma). This unique pathologic finding has only been rarely reported and is discussed with a brief review of the literature. PMID:27247824

  11. Resection and Abdominal Wall Reconstruction of a Desmoid Tumor with Endometrioma Features.

    PubMed

    Majors, Jaqueline; Stoikes, Nathaniel F; Nejati, Reza; Deneve, Jeremiah L

    2016-01-01

    Desmoid tumors are rare, musculoaponeurotic mesenchymal origin tumors arising from the proliferation of well-differentiated fibroblasts. Desmoid tumors may arise from any location with the abdominal cavity, abdominal wall and extremity locations being most frequent. We present the case of a 35-year-old female with a history of endometriosis who presented palpable abdominal mass and cyclic abdominal pain. Resection was performed for a presumed desmoid soft tissue tumor. Final pathology demonstrated desmoid histology admixed with abdominal wall endometriosis (endometrioma). This unique pathologic finding has only been rarely reported and is discussed with a brief review of the literature. PMID:27247824

  12. An Abdominal Aorta Wall Extraction for Liver Cirrhosis Classification Using Ultrasonic Images

    NASA Astrophysics Data System (ADS)

    Hayashi, Takaya; Fujita, Yusuke; Mitani, Yoshihiro; Hamamoto, Yoshihiko; Segawa, Makoto; Terai, Shuji; Sakaida, Isao

    2011-06-01

    We propose a method to extract an abdominal aorta wall from an M-mode image. Furthermore, we propose the use of a Gaussian filter in order to improve image quality. The experimental results show that the Gaussian filter is effective in the abdominal aorta wall extraction.

  13. [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

  14. Spontaneous intraamniotic hemorrhage in the second trimester mimicking an abdominal wall defect

    PubMed Central

    Üstüner, Işık; Güven, Emine Seda Güvendağ; Balık, Gülşah; Şentürk, Şenol; Üstüner, Evren; Atman, Ebru Düşünceli; Avşar, Ayşe Filiz

    2013-01-01

    We report here a case of spontaneous intraamniotic haemorrhage in the second trimester which mimicked an abdominal wall defect. The ultrasound and magnetic resonance imaging findings are discussed and a review of the literature regarding differential diagnosis of bleeding and abdominal wall defects is made. PMID:24592085

  15. Domain wall motion in ferroelectrics: Barkhausen noise

    NASA Astrophysics Data System (ADS)

    Shur, V.; Rumyantsev, E.; Kozhevnikov, V.; Nikolaeva, E.; Shishkin, E.

    2002-03-01

    The switching current noise has been recorded during polarization reversal in single-crystalline gadolinium molybdate (GMO) and lithium tantalate (LT). Analysis of Barkhausen noise (BN) data allows to classify the noise types by determination of the critical indexes and fractal dimensions. BN is manifested as the short pulses during the polarization reversal. We have analyzed the BN data recorded in GMO and LT with various types of controlled domain structure. The data treatment in terms of probability distribution of duration, area and energy of individual pulses reveals the critical behavior typical for the fractal records in time. We used the Fourier transform and Hurst's rescaled range analysis for obtaining the Hurst factor, fractal dimension and classifying the noise types. We investigated by computer simulation the mechanism of sideways motion of 180O domain wall by nucleation at the wall taking into account the nuclei-nuclei interaction. It was shown that the moving domain walls display the fractal shape and their motion is accompanied by Flicker noise, which is in accord with experimental data. The research was made possible in part by Programs "Basic Research in Russian Universities" and "Priority Research in High School. Electronics", by Grant No. 01-02-17443 of RFBR, by Award No.REC-005 of CRDF.

  16. [Mutual influence and development between Gastrointestinal surgery and hernia and abdominal wall surgery].

    PubMed

    Chen, Shuang

    2015-11-25

    The aim of this article is to expound on the crossing and influence each other of gastrointestinal surgery and abdominal wall hernia surgery. Although these two departments are independent respectively, but due to the existence of association among anatomy, physiology and pathology, so they are also overlapping. First of all, the abdominal wall and digestive tract are interdependent, and the abdominal wall provides "protection" for gut. In case of large abdominal wall defect, intra-abdominal viscera, breathing, circulation system and spine will change accordingly. In addition, when intra-abdominal pressure increases due to various reasons, laparotomy is an effective way. But laparotomy is not an easy case, but a crisis. One of the most difficult problems is "enteroatmospheric fistulae". Therefore, to avoid serious complications after laparotomy, the concept of planned ventral hernia is proposed. When life safety is threatened by inter-abdominal hypertension, planned abdominal wall hernia is the style to save life. This is a kind of concept of innovation, and is the concrete practice of the theory of damage control surgery. For a planned abdominal wall hernia patient, it is better to wait and watch, and after making a comprehensive assessment, multidisciplinary collaboration mode should be applied to ensure the safety of surgery. PMID:26616795

  17. Neuromuscular independence of abdominal wall muscles as demonstrated by middle-eastern style dancers.

    PubMed

    Moreside, Janice M; Vera-Garcia, Francisco J; McGill, Stuart M

    2008-08-01

    Previous studies analyzing neuromuscular independence of the abdominal wall have involved a participant population with no specific training in separating individual muscle segments. We chose to study nine women trained in the art of middle-eastern dance, anticipating they may have unique skills in motor control. Specifically, we were searching for evidence of separation of upper rectus abdominis (URA) from lower rectus abdominis (LRA), as well as understanding what role the oblique muscles play in abdominal wall synergies. EMG analysis was done on eight trunk muscles bilaterally as the dancers participated in 30 dance, planar, and curl-up activities. The filtered data were then cross-correlated to determine the time lag between pairs of signals. Only three dance movements demonstrated consistent evidence of an ability to separate URA/LRA activation timing. The external and internal oblique muscles tend to align themselves temporally with the LRA. However, these findings were only evident in these three specific "belly-roll" conditions, all with low levels of muscle activation, and no external torque. Evidence of significantly different activation levels (% MVC) between URA/LRA was demonstrated in eight conditions, all of which required various pelvis movements with minimal thorax motion. PMID:17329127

  18. Blunt Abdominal Wall Disruption by Seatbelt Injury; A Case Report and Review of the Literature

    PubMed Central

    Cornelissen, Maarten Philip; van Buijtenen, Jesse; van den Heuvel, Baukje; Bloemers, Frank; Geeraedts Jr., Leo

    2016-01-01

    With the introduction of the use of seatbelts in cars, mortality following motor vehicle crashes has decreased significantly. However, two patterns of injuries, the ‘seatbelt sign’ and ‘seatbelt syndrome’ have emerged. Injuries may consist of traumatic abdominal wall disruption. We present two cases of severe abdominal wall disruption caused by a seatbelt injury and treated with primary repair. A review of the literature is provided. Two patients were brought in after a high velocity Motor Vehicle Collision. Both presented with an acute abdomen and a seatbelt sign upon which the decision was made to perform emergency laparotomies. Both patients had an abdominal wall disruption along the seatbelt sign. These disruptions were primarily closed and during six months of follow-up no complications occurred. A disruption of the abdominal wall is a rare complication. However, it is a diagnosis that may not be missed as patients have a higher risk of morbidity and mortality. CT-scanning is an accurate method to detect disruptions. Closure of blunt traumatic abdominal wall disruption can be done primarily with sutures or addition of a mesh. In both cases of the severe abdominal wall disruption, primary repair without mesh in the acute phase was successful. When a laparotomy is not indicated, the abdominal wall must be assessed for disruption. If there is a disruption primary repair is a good option. PMID:27331068

  19. A Novel Diagnostic Aid for Detection of Intra-Abdominal Adhesions to the Anterior Abdominal Wall Using Dynamic Magnetic Resonance Imaging

    PubMed Central

    Randall, David; Fenner, John; Gillott, Richard; ten Broek, Richard; Strik, Chema; Spencer, Paul; Bardhan, Karna Dev

    2016-01-01

    Introduction. Abdominal adhesions can cause serious morbidity and complicate subsequent operations. Their diagnosis is often one of exclusion due to a lack of a reliable, non-invasive diagnostic technique. Development and testing of a candidate technique are described below. Method. During respiration, smooth visceral sliding motion occurs between the abdominal contents and the walls of the abdominal cavity. We describe a technique involving image segmentation and registration to calculate shear as an analogue for visceral slide based on the tracking of structures throughout the respiratory cycle. The presence of an adhesion is attributed to a resistance to visceral slide resulting in a discernible reduction in shear. The abdominal movement due to respiration is captured in sagittal dynamic MR images. Results. Clinical images were selected for analysis, including a patient with a surgically confirmed adhesion. Discernible reduction in shear was observed at the location of the adhesion while a consistent, gradually changing shear was observed in the healthy volunteers. Conclusion. The technique and its validation show encouraging results for adhesion detection but a larger study is now required to confirm its potential. PMID:26880884

  20. The use of a biological graft for the closure of large abdominal wall defects following excision of soft tissue tumours

    PubMed Central

    Illingworth, Emma; Rooney, Paul S.; Heath, Richard; Chandrasekar, Coonoor R.

    2015-01-01

    Primary soft tissue tumours arising from the abdominal wall are uncommon and surgical excision of such tumours can result in large abdominal wall defects. There are many techniques available for abdominal wall repair following tumour excision, each having its own advantages and disadvantages. The options range from direct closure to the use of tissue flap reconstructions and/or prosthetic meshes. Currently, synthetic material such as polypropylene mesh is a common choice for closure of abdominal wall defects after tumour excision. Biological meshes are an alternative option for repair, and this report outlines two cases of abdominal wall repair using the porcine intestinal submucosa biological graft following excision of abdominal wall tumours. There was no evidence of infection, recurrence, seroma or hernias at 2-year follow-up. Following excision of soft tissue tumours of the abdominal wall, biological reconstructions can be successfully used to bridge the defect with minimal morbidity. PMID:26109681

  1. Microgravity alters respiratory abdominal and rib cage motion during sleep

    PubMed Central

    Prisk, G. Kim; Paiva, Manuel

    2009-01-01

    The abdominal and rib cage contributions to tidal breathing differ between rapid-eye-movement (REM) and non-NREM sleep. We hypothesized that abdominal relative contribution during NREM and REM sleep would be altered in different directions when comparing sleep on Earth with sleep in sustained microgravity (μG), due to conformational changes and differences in coupling between the rib cage and the abdominal compartment induced by weightlessness. We studied respiration during sleep in five astronauts before, during, and after two Space Shuttle missions. A total of 77 full-night (8 h) polysomnographic studies were performed; abdominal and rib cage respiratory movements were recorded using respiratory inductive plethysmography. Breath-by-breath analysis of respiration was performed for each class: awake, light sleep, deep sleep, and REM sleep. Abdominal contribution to tidal breathing increased in μG, with the first measure in space being significantly higher than preflight values, followed by a return toward preflight values. This was observed for all classes. Preflight, rib cage, and abdominal movements were found to be in phase for all but REM sleep, for which an abdominal lead was observed. The abdominal leading role during REM sleep increased while deep sleep showed the opposite behavior, the rib cage taking a leading role in-flight. In μG, the percentage of inspiratory time in the overall breath, the duty cycle (TI/TTot), decreased for all classes considered when compared with preflight, while normalized inspiratory flow, taking the awake values as reference, increased in-flight for light sleep, deep sleep, and REM. Changes in abdominal-rib cage displacements probably result from a less efficient operating point for the diaphragm and a less efficient coupling between the abdomen and the apposed portion of the rib cage in μG. However, the preservation of total ventilation suggests that short-term adaptive mechanisms of ventilatory control compensate for these

  2. Combination of tissue expansion and porcine mesh for secondary abdominal wall closure after pediatric liver transplantation.

    PubMed

    Lafosse, Aurore; de Magnee, Catherine; Brunati, Andrea; Bayet, Bénédicte; Vanwijck, Romain; Manzanares, Javier; Reding, Raymond

    2012-08-01

    We report the case of a two and a half yr boy hospitalized in our Pediatric Transplantation Unit for portal vein thrombosis following liver transplantation. After performing a meso-Rex shunt, abdominal wall closure was impossible without compressing the portal flow. A combination of two techniques was used to perform the reconstruction of the muscular fasciae and skin layers. The association of tissue expanders and porcine mesh (Surgisis(®)) allowed complete abdominal wall closure with good functional and esthetic results. Use of both techniques is a useful alternative for difficult abdominal closure after liver pediatric transplantation. PMID:21848529

  3. The surface landmarks of the abdominal wall: a plea for standardization

    PubMed Central

    Cirocchi, Roberto; Boselli, Carlo; Renzi, Claudio; Cagini, Lucio; Boccolini, Andrea; Noya, Giuseppe; Fingerhut, Abe

    2014-01-01

    Despite centuries of anatomical studies, controversies and contradictions still exist in the literature regarding the definition, anatomical terminology and the limits of the abdominal wall. We conducted a systematic research of books published from 1901 until December 2012 in Google Books. After the index screening, 16 remaining books were further assessed for eligibility. We decided to exclude journals. The aim of the study was to focus on surface landmarks and borders of the abdominal cavity. After this revision of the literature, we propose that the surface landmarks of the abdominal wall should be standardized. PMID:25097589

  4. Reproducibility of The Abdominal and Chest Wall Position by Voluntary Breath-Hold Technique Using a Laser-Based Monitoring and Visual Feedback System

    SciTech Connect

    Nakamura, Katsumasa . E-mail: nakam@radiol.med.kyushu-u.ac.jp; Shioyama, Yoshiyuki; Nomoto, Satoru; Ohga, Saiji; Toba, Takashi; Yoshitake, Tadamasa; Anai, Shigeo; Terashima, Hiromi; Honda, Hiroshi

    2007-05-01

    Purpose: The voluntary breath-hold (BH) technique is a simple method to control the respiration-related motion of a tumor during irradiation. However, the abdominal and chest wall position may not be accurately reproduced using the BH technique. The purpose of this study was to examine whether visual feedback can reduce the fluctuation in wall motion during BH using a new respiratory monitoring device. Methods and Materials: We developed a laser-based BH monitoring and visual feedback system. For this study, five healthy volunteers were enrolled. The volunteers, practicing abdominal breathing, performed shallow end-expiration BH (SEBH), shallow end-inspiration BH (SIBH), and deep end-inspiration BH (DIBH) with or without visual feedback. The abdominal and chest wall positions were measured at 80-ms intervals during BHs. Results: The fluctuation in the chest wall position was smaller than that of the abdominal wall position. The reproducibility of the wall position was improved by visual feedback. With a monitoring device, visual feedback reduced the mean deviation of the abdominal wall from 2.1 {+-} 1.3 mm to 1.5 {+-} 0.5 mm, 2.5 {+-} 1.9 mm to 1.1 {+-} 0.4 mm, and 6.6 {+-} 2.4 mm to 2.6 {+-} 1.4 mm in SEBH, SIBH, and DIBH, respectively. Conclusions: Volunteers can perform the BH maneuver in a highly reproducible fashion when informed about the position of the wall, although in the case of DIBH, the deviation in the wall position remained substantial.

  5. Testicular Ectopia in the Anterior Abdominal Wall of a Neonate: A Rare Site of Ectopic Testis.

    PubMed

    Siddiqui, Salman Atiq; Marei, Tamer Ibrahim; Al-Makhaita, Ghada

    2016-01-01

    BACKGROUND Abnormal testicular descent can either be undescended or, less commonly, ectopic. Most undescended testes complete the course of descent by the first year of life only if these remain in the normal path of descent. The deviation of the testis may occur to an ectopic location during the transinguinal phase. Of the known ectopic sites, the anterior abdominal wall is the rarest site of testicular ectopia and to our knowledge only 3 cases of this nature have been reported in the available literature to date.  CASE REPORT This rare case of testicular ectopia occurred in a 3-day-old boy in whom the right scrotal sac was empty; on abdominal ultrasound, the right testis was found in the subcutaneous tissues of the right antero-lateral abdominal wall. These findings were confirmed on abdominal MRI, where the right testis was seen beneath the skin between the subcutaneous tissues and external oblique aponeurosis. No aponeurotic or muscular defect was appreciable under the abdominal wall. The neonate underwent orchiopexy at the age of 6 months and remained uneventful postoperatively. CONCLUSIONS Preoperative imaging is recommended to detect and confirm the ectopic site as well as the morphology of testis, thereby increasing the chance of surveillance and preservation of an ectopic testis. Imaging can serve as preoperative road mapping to localize the exact site for surgical exploration of an ectopic testis if there is no apparent or palpable swelling over the anterior abdominal wall. PMID:27411886

  6. Architectural Analysis of Human Abdominal Wall Muscles: Implications for Mechanical Function

    PubMed Central

    Brown, Stephen H. M.; Ward, Samuel R.; Cook, Mark S.; Lieber, Richard L.

    2010-01-01

    Study Design Cadaveric analysis of human abdominal muscle architecture. Objective To quantify the architectural properties of rectus abdominis (RA), external oblique (EO), internal oblique (IO) and transverse abdominis (TrA), and model mechanical function in light of these new data. Summary of Background Data Knowledge of muscle architecture provides the structural basis for predicting muscle function. Abdominal muscles greatly affect spine loading, stability, injury prevention and rehabilitation; however, their architectural properties are unknown. Methods Abdominal muscles from eleven elderly human cadavers were removed intact, separated into regions and micro-dissected for quantification of physiological cross-sectional area (PCSA), fascicle length and sarcomere length. From these data, sarcomere operating length ranges were calculated. Results IO had the largest PCSA and RA the smallest, and would thus generate the largest and smallest isometric forces, respectively. RA had the longest fascicle length, followed by EO, and would thus be capable of generating force over the widest range of lengths. Measured sarcomere lengths, in the post-mortem neutral spine posture, were significantly longer in RA and EO (3.29±0.07 and 3.18±0.11 μm) compared to IO and TrA (2.61±0.06 and 2.58±0.05 μm) (p < 0.0001). Biomechanical modeling predicted that RA, EO and TrA act at optimal force-generating length in the mid-range of lumbar spine flexion, where IO can generate approximately 90% of its maximum force. Conclusions These data provide clinically relevant insights into the ability of the abdominal wall muscles to generate force and change length throughout the lumbar spine range of motion. This will impact the understanding of potential postures in which the force-generating and spine stabilizing ability of these muscles become compromised, which can guide exercise/rehabilitation development and prescription. Future work should explore the mechanical interactions among

  7. Paragonimiasis mimicking chest cancer and abdominal wall metastaisis: A case report

    PubMed Central

    ZHOU, RONGXING; ZHANG, MINJIA; CHENG, NANSHENG; ZHOU, YONG

    2016-01-01

    Typical human paragonimiasis demonstrates an elevated eosinophil count, positive immunoblot, nodular shadows of the lung and pleural thickening with pleural effusion, and these symptoms may be confused with chest cancer. In the present case, a rare case of human paragonimiasis mimicking chest cancer and abdominal wall metastasis is described, the 39-year-old male patient was admitted in our hospital for cough, weight loss 5 kg and a firm mass in right upper abdominal wall. The laboratory test showed unremarkable hematology and biochemistry results. Chest X-ray, Plain computed tomography of the chest and abdomen showed right pleural effusion, several nodules in right lower lung and a mass in the right upper abdominal wall. The initial diagnosis was lung or chest cancer with abdominal wall metastasis, and the abdominal wall mass was resected for the final diagnosis. The biopsy revealed eosinophilic granuloma with Charcot-Leyden crystal formation infiltrated in the muscular fibers. Subsequent to assessment of the antibodies against parasites, the final diagnosis of paragonimiasis was made. PMID:27313691

  8. Testicular Ectopia in the Anterior Abdominal Wall of a Neonate: A Rare Site of Ectopic Testis

    PubMed Central

    Siddiqui, Salman Atiq; Marei, Tamer Ibrahim; Al-Makhaita, Ghada

    2016-01-01

    Patient: Male, 3-day Final Diagnosis: Ectopic right testis in anterior abdominal wall Symptoms: — Medication: — Clinical Procedure: Testicular ultrasound and MRI abdomen Specialty: Radiology Objective: Unusual clinical course Background: Abnormal testicular descent can either be undescended or, less commonly, ectopic. Most undescended testes complete the course of descent by the first year of life only if these remain in the normal path of descent. The deviation of the testis may occur to an ectopic location during the transinguinal phase. Of the known ectopic sites, the anterior abdominal wall is the rarest site of testicular ectopia and to our knowledge only 3 cases of this nature have been reported in the available literature to date. Case Report: This rare case of testicular ectopia occurred in a 3-day-old boy in whom the right scrotal sac was empty; on abdominal ultrasound, the right testis was found in the subcutaneous tissues of the right antero-lateral abdominal wall. These findings were confirmed on abdominal MRI, where the right testis was seen beneath the skin between the subcutaneous tissues and external oblique aponeurosis. No aponeurotic or muscular defect was appreciable under the abdominal wall. The neonate underwent orchiopexy at the age of 6 months and remained uneventful postoperatively. Conclusions: Preoperative imaging is recommended to detect and confirm the ectopic site as well as the morphology of testis, thereby increasing the chance of surveillance and preservation of an ectopic testis. Imaging can serve as preoperative road mapping to localize the exact site for surgical exploration of an ectopic testis if there is no apparent or palpable swelling over the anterior abdominal wall. PMID:27411886

  9. Texture analysis improves level set segmentation of the anterior abdominal wall

    SciTech Connect

    Xu, Zhoubing; Allen, Wade M.; Baucom, Rebeccah B.; Poulose, Benjamin K.; Landman, Bennett A.

    2013-12-15

    Purpose: The treatment of ventral hernias (VH) has been a challenging problem for medical care. Repair of these hernias is fraught with failure; recurrence rates ranging from 24% to 43% have been reported, even with the use of biocompatible mesh. Currently, computed tomography (CT) is used to guide intervention through expert, but qualitative, clinical judgments, notably, quantitative metrics based on image-processing are not used. The authors propose that image segmentation methods to capture the three-dimensional structure of the abdominal wall and its abnormalities will provide a foundation on which to measure geometric properties of hernias and surrounding tissues and, therefore, to optimize intervention.Methods: In this study with 20 clinically acquired CT scans on postoperative patients, the authors demonstrated a novel approach to geometric classification of the abdominal. The authors’ approach uses a texture analysis based on Gabor filters to extract feature vectors and follows a fuzzy c-means clustering method to estimate voxelwise probability memberships for eight clusters. The memberships estimated from the texture analysis are helpful to identify anatomical structures with inhomogeneous intensities. The membership was used to guide the level set evolution, as well as to derive an initial start close to the abdominal wall.Results: Segmentation results on abdominal walls were both quantitatively and qualitatively validated with surface errors based on manually labeled ground truth. Using texture, mean surface errors for the outer surface of the abdominal wall were less than 2 mm, with 91% of the outer surface less than 5 mm away from the manual tracings; errors were significantly greater (2–5 mm) for methods that did not use the texture.Conclusions: The authors’ approach establishes a baseline for characterizing the abdominal wall for improving VH care. Inherent texture patterns in CT scans are helpful to the tissue classification, and texture

  10. A diode for ferroelectric domain-wall motion

    PubMed Central

    Whyte, J.R.; Gregg, J.M.

    2015-01-01

    For over a decade, controlling domain-wall injection, motion and annihilation along nanowires has been the preserve of the nanomagnetics research community. Revolutionary technologies have resulted, like racetrack memory and domain-wall logic. Until recently, equivalent research in analogous ferroic materials did not seem important. However, with the discovery of sheet conduction, the control of domain walls in ferroelectrics has become vital for the future of what has been termed ‘domain-wall electronics'. Here we report the creation of a ferroelectric domain-wall diode, which allows a single direction of motion for all domain walls, irrespective of their polarity, under a series of alternating electric field pulses. The diode's sawtooth morphology is central to its function. Domain walls can move readily in the direction in which thickness increases gradually, but are prevented from moving in the other direction by the sudden thickness increase at the sawtooth edge. PMID:26059779

  11. Early metastasis to anterior abdominal wall following radical cystectomy: A rare presentation

    PubMed Central

    Sawant, Ajit; Bansal, Sumit; Pawar, Prakash; Kasat, Gaurav

    2016-01-01

    Abdominal wall metastasis from urothelial cancer is extremely rare and very few such cases have been reported in the literature. As such the treatment protocols are not so well defined. We present an interesting case of a 65-year-old male patient, known case of chronic kidney disease, who presented with a large, fungating infraumbilical mass 8 months postradical cystectomy. The mass involved full thickness anterior abdominal wall and small bowel including the ileal conduit. Wide excision of the mass along with adhered bowel loops and partial excision of the ileal conduit with right ureteric reimplant was performed. The large defect in the anterior abdominal wall was closed using a mesh (permanent with a bioresorbable coating inside) and myocutaneous thigh flap. The histopathological examination of the excised mass was consistent with secondary from the urothelial tumor. PMID:27453672

  12. Living donor liver transplantation with abdominal wall reconstruction for hepatocellular carcinoma with needle track seeding

    PubMed Central

    Yang, Horng-Ren; Thorat, Ashok; Gesakis, Kanellos; Li, Ping-Chun; Kiranantawat, Kidakorn; Chen, Hung Chi; Jeng, Long-Bin

    2015-01-01

    Malignant cell seeding in subcutaneous tissues along the needle track and/or percutaneous biliary drainage catheters is rare complication, but pose various technical issues in planning surgical treatment of such patients. If underlying primary hepatic malignancy can be treated, an aggressive resection of subcutaneous tissue bearing cancer cell with subsequent abdominal wall reconstruction has been sporadically reported. But, when hepatic resection is not possible due to underlying advanced cirrhosis, liver transplantation along with abdominal wall resection and subsequent reconstruction remains only feasible option. Herein, we describe our successful experience of living donor liver transplantation for hepatocellular carcinoma with full-thickness abdominal wall resection bearing the tumor seeding followed by reconstruction in single stage surgery. PMID:26722665

  13. Device transmits rotary motion through hermetically sealed wall

    NASA Technical Reports Server (NTRS)

    Porter, R. N.

    1964-01-01

    A wobble plate, metal bellows, and two shafts, assembled in a four-section housing, make it possible to transmit rotary motion through a hermetically sealed wall. In operation a rotational torque is developed by the wobble plate.

  14. Fungating carcinoma of the stomach: en bloc multiple organ resection and abdominal wall reconstruction.

    PubMed Central

    Chu, K. M.; Lai, D. T.; Stern, H. S.; Sheldon, D. M.

    1995-01-01

    A patient with carcinoma of the stomach invading multiple adjacent organs and fungating through the anterior abdominal wall was treated by en bloc multiple organ resection and abdominal wall reconstruction. The patient is alive and well at the time of writing, six months after the operation. The rationale for embarking on multiple organ resection for gastric cancer is discussed. However, such an aggressive surgical approach should only be applied to carefully selected patients who are medically fit and have no evidence of widespread systemic metastases. Images Figure PMID:7596940

  15. Unusual Presentations of Actinomycosis; Anterior Abdominal Wall and Appendix: Report of Three Cases

    PubMed Central

    Karateke, Faruk; Özyazıcı, Sefa; Menekşe, Ebru; Daş, Koray; Özdoğan, Mehmet

    2013-01-01

    Background: Primary actinomycosis of the anterior abdominal wall and appendix are very rare clinical entities. An accurate diagnosis is generally obtained by histological examination, and treatment often requires surgical resection. Case Report: In this study we presented two cases of primary actinomycosis involving the anterior abdominal wall and a third one located in the appendix. Conclusion: Actinomyces Israelii can involve all anatomic structures of the abdomen. Although preoperative diagnosis is difficult, the combination of surgery and antibiotic treatment results in complete treatment in the majority of cases. PMID:25207127

  16. Polymicrobial abdominal wall necrotizing fasciitis after cesarean section.

    PubMed

    DeMuro, Jp; Hanna, Af; Chalas, E; Cunha, Ba

    2012-01-01

    We report a case of a previously healthy woman after an uneventful caesarean section who developed polymicrobial necrotizing fasciitis. She was given a non-steroidal anti-inflamatory drug (NSAID) after her delivery. Her post-delivery course was complicated by septic shock, and required multiple debridements before abdominal reconstruction. This case describes the increased risk of necrotizing fasciitis with NSAID use. Unusual were the organisms causing the polymicrobial necrotizing fasciitis: Staphylococcus aureus, Enterobacter agglomerans, Acinetobacter baumannii, and two strains of Enterobacter cloacae. PMID:24960796

  17. Contraction of Abdominal Wall Muscles Influences Incisional Hernia Occurrence and Size

    PubMed Central

    Lien, Samuel C.; Hu, Yaxi; Wollstein, Adi; Franz, Michael G.; Patel, Shaun P.; Kuzon, William M.; Urbanchek, Melanie G.

    2015-01-01

    Background Incisional hernias are a complication in 10% of all open abdominal operations and can result in significant morbidity. The purpose of this study is to determine if inhibiting abdominal muscle contraction influences incisional hernia formation during laparotomy healing. We hypothesize that reducing abdominal musculature deformation reduces incisional hernia occurrence and size. Study Design Using an established rat model for incisional hernia, a laparotomy through the linea alba was closed with one mid-incision, fast-absorbing suture. Three groups were compared: a SHAM group (SHAM; n = 6) received no laparotomies while the Saline Hernia (SH; n = 6) and Botox Hernia (BH; n = 6) groups were treated once with equal volume saline or Botulinum Toxin (Botox®, Allergan) before the incomplete laparotomy closure. On post-operative day 14, the abdominal wall was examined for herniation and adhesions and contractile forces were measured for abdominal wall muscles. Results No hernias developed in SHAM rats. Rostral hernias developed in all SH and BH rats. Caudal hernias developed in all SH rats, but in only 50% of the BH rats. Rostral hernias in the BH group were 35% shorter and 43% narrower compared to those in the SH group (p < 0.05). The BH group had weaker abdominal muscles compared to the SHAM and SH groups (p < 0.05). Conclusions In our rat model, partial paralysis of abdominal muscles reduces the number and size of incisional hernias. These results confirm abdominal wall muscle contractions play a significant role in the pathophysiology of incisional hernia formation. PMID:25817097

  18. A Four-Dimensional Computed Tomography Analysis of Multiorgan Abdominal Motion

    SciTech Connect

    Hallman, Joshua L.; Mori, Shinichiro; Sharp, Gregory C.; Lu, Hsiao-Ming; Hong, Theodore S.; Chen, George T.Y.

    2012-05-01

    Purpose: To characterize and quantify multiorgan respiration-induced motion in the abdomen in liver and pancreatic cancer patients. Methods and Materials: Four-dimensional computed tomography scans were acquired for 18 patients treated for abdominal tumors. Contours of multiple abdominal organs were drawn by the radiation oncologist at one respiratory phase; these contours were propagated to other respiratory phases by deformable registration. Three-dimensional organ models were generated from the resulting contours at each phase. Motions of the bounding box and center of mass were extracted and analyzed for the clinical target volume and organs at risk. Results: On average, the center of mass motion for liver clinical target volumes was 9.7 mm (SD 5 mm) in the superior-inferior direction, with a range of 3 to 18 mm; for pancreatic tumors, the average was 5 mm (SD 1 mm) m with a range of 3 to 7 mm. Abdominal organs move in unison, but with varying amplitudes. Gating near exhale (T40-T60) reduces the range of motion by a factor of {approx}10. Conclusion: We have used deformable registration to calculate the trajectories of abdominal organs in four dimensions, based on center of mass and bounding box motion metrics. Our results are compared with previously reported studies. Possible reasons for differences are discussed.

  19. External respiratory motion for abdominal radiotherapy patients: implications for patient alignment

    SciTech Connect

    Kearvell, Rachel; Ebert, Martin A

    2003-12-31

    Conformal external beam radiotherapy relies on accurate spatial positioning of the tumor and normal tissues during treatment. For abdominal patients, this is complicated by the motion of internal organs and the external patient contour due to respiration. As external motion influences the degree of accuracy achievable in patient setup, this motion was studied to provide indication of motions occurring during treatment, as well as to assess the technique of breath-holding at exhale (B-HEX). The motion of external abdominal points (anterior and right lateral) of a series of volunteers was tracked in real-time using an infrared tracking system, with the volunteers in treatment position. The resulting motion data was assessed to evaluate (1) the change in position of each point per breath/breath-hold, (2) the change in position between breaths/breath-holds, and (3) the change in position across the whole recording time. Analysis shows that, for the anterior abdominal point, there is little difference in the variation of position with time for free-breathing as opposed to the B-HEX technique. For the lateral point however, the B-HEX technique reduces the motion during each treatment cycle (i.e., during the breath-hold) and over an extended period (i.e., during a series of breath-holds). The B-HEX technique thus provides greater accuracy for setup to lateral markers and provides the opportunity to reduce systematic and random localization errors.

  20. Abdominal wall muscle elasticity and abdomen local stiffness on healthy volunteers during various physiological activities.

    PubMed

    Tran, D; Podwojewski, F; Beillas, P; Ottenio, M; Voirin, D; Turquier, F; Mitton, D

    2016-07-01

    The performance of hernia treatment could benefit from more extensive knowledge of the mechanical behavior of the abdominal wall in a healthy state. To supply this knowledge, the antero-lateral abdominal wall was characterized in vivo on 11 healthy volunteers during 4 activities: rest, pullback loading, abdominal breathing and the "Valsalva maneuver". The elasticity of the abdominal muscles (rectus abdominis, obliquus externus, obliquus internus and transversus abdominis) was assessed using ultrasound shear wave elastography. In addition, the abdomen was subjected to a low external load at three locations: on the midline (linea alba), on the rectus abdominis region and on lateral muscles region in order to evaluate the local stiffness of the abdomen, at rest and during "Valsalva maneuver". The results showed that the "Valsalva maneuver" leads to a statistically significant increase of the muscle shear modulus compared to the other activities. This study also showed that the local stiffness of the abdomen was related to the activity. At rest, a significant difference has been observed between the anterior (0.5N/mm) and the lateral abdomen locations (1N/mm). Then, during the Valsalva maneuver, the local stiffness values were similar for all locations (ranging from 1.6 to 2.2N/mm). This work focuses on the in vivo characterization of the mechanical response of the human abdominal wall and abdomen during several activities. In the future, this protocol could be helpful for investigation on herniated patients. PMID:26994992

  1. Primary synovial sarcoma of the abdominal wall: a case report and literature review

    PubMed Central

    Kritsaneepaiboon, Supika; Sangkhathat, Surasak; Mitarnun, Winyou

    2015-01-01

    Synovial sarcoma (SS) is the fourth most common type of soft tissue sarcoma, following malignant fibrous histiocytoma, liposarcoma, and rhabdomyosarcoma. It usually occurs in the extremities near the large joints of middle-aged patients. We describe a case of synovial sarcoma of the anterior abdominal wall (SSAW) in an adolescent girl and undertake a review of the literature. PMID:26629297

  2. US and MRI features in venous vascular malformation of the abdominal wall. A case report

    PubMed Central

    Alessandrino, F.; Maira, A.; Tarantino, C.C.

    2012-01-01

    Vascular anomalies are classified as vascular tumors and vascular malformations. Venous vascular malformations are the most common type of vascular malformation. They may be isolated or multiple and they rarely affect the trunk. The authors report a rare case of isolated venous vascular malformation of the abdominal wall with an emphasis on the related MRI and ultrasound (US) features. PMID:23450707

  3. Semiautomatic vessel wall detection and quantification of wall thickness in computed tomography images of human abdominal aortic aneurysms

    SciTech Connect

    Shum, Judy; DiMartino, Elena S.; Goldhammer, Adam; Goldman, Daniel H.; Acker, Leah C.; Patel, Gopal; Ng, Julie H.; Martufi, Giampaolo; Finol, Ender A.

    2010-02-15

    Purpose: Quantitative measurements of wall thickness in human abdominal aortic aneurysms (AAAs) may lead to more accurate methods for the evaluation of their biomechanical environment. Methods: The authors describe an algorithm for estimating wall thickness in AAAs based on intensity histograms and neural networks involving segmentation of contrast enhanced abdominal computed tomography images. The algorithm was applied to ten ruptured and ten unruptured AAA image data sets. Two vascular surgeons manually segmented the lumen, inner wall, and outer wall of each data set and a reference standard was defined as the average of their segmentations. Reproducibility was determined by comparing the reference standard to lumen contours generated automatically by the algorithm and a commercially available software package. Repeatability was assessed by comparing the lumen, outer wall, and inner wall contours, as well as wall thickness, made by the two surgeons using the algorithm. Results: There was high correspondence between automatic and manual measurements for the lumen area (r=0.978 and r=0.996 for ruptured and unruptured aneurysms, respectively) and between vascular surgeons (r=0.987 and r=0.992 for ruptured and unruptured aneurysms, respectively). The authors' automatic algorithm showed better results when compared to the reference with an average lumen error of 3.69%, which is less than half the error between the commercially available application Simpleware and the reference (7.53%). Wall thickness measurements also showed good agreement between vascular surgeons with average coefficients of variation of 10.59% (ruptured aneurysms) and 13.02% (unruptured aneurysms). Ruptured aneurysms exhibit significantly thicker walls (1.78{+-}0.39 mm) than unruptured ones (1.48{+-}0.22 mm), p=0.044. Conclusions: While further refinement is needed to fully automate the outer wall segmentation algorithm, these preliminary results demonstrate the method's adequate reproducibility

  4. Robust Spectral Analysis of Thoraco-Abdominal Motion and Oxymetry in Obstructive Sleep Apnea

    PubMed Central

    Nino, Cesar L.; Rodriguez-Martinez, Carlos E.; Gutierrez, Maria J.; Singareddi, Ravi; Nino, Gustavo

    2014-01-01

    Standard PSG montage involves the use of nasal-oral airflow sensors to visualize cyclic episodes of upper airflow interruption, which are considered diagnostic of sleep apnea. Given the high-cost and discomfort associated with in-laboratory PSG, there is an emergent need for novel technology that simplifies OSA screening and diagnosis with less expensive methods. The main goal of this project was to identify novel OSA signatures based on the spectral analysis of thoraco-abdominal motion channels. Our main hypothesis was that proper spectral analysis can detect OSA cycles in adults using simultaneous recording of SaO2 and either, chest or abdominal motion. The impact of this new approach is that it may allow the design of more comfortable and reliable portable devices for screening, diagnosis and monitoring of OSA, functioning only with oximetry and airflow-independent (abdominal or chest) breathing sensors. PMID:24110335

  5. Intraventricular flow alterations due to dyssynchronous wall motion

    NASA Astrophysics Data System (ADS)

    Pope, Audrey M.; Lai, Hong Kuan; Samaee, Milad; Santhanakrishnan, Arvind

    2015-11-01

    Roughly 30% of patients with systolic heart failure suffer from left ventricular dyssynchrony (LVD), in which mechanical discoordination of the ventricle walls leads to poor hemodynamics and suboptimal cardiac function. There is currently no clear mechanistic understanding of how abnormalities in septal-lateral (SL) wall motion affects left ventricle (LV) function, which is needed to improve the treatment of LVD using cardiac resynchronization therapy. We use an experimental flow phantom with an LV physical model to study mechanistic effects of SL wall motion delay on LV function. To simulate mechanical LVD, two rigid shafts were coupled to two segments (apical and mid sections) along the septal wall of the LV model. Flow through the LV model was driven using a piston pump, and stepper motors coupled to the above shafts were used to locally perturb the septal wall segments relative to the pump motion. 2D PIV was used to examine the intraventricular flow through the LV physical model. Alterations to SL delay results in a reduction in the kinetic energy (KE) of the flow field compared to synchronous SL motion. The effect of varying SL motion delay from 0% (synchronous) to 100% (out-of-phase) on KE and viscous dissipation will be presented. This research was supported by the Oklahoma Center for Advancement of Science and Technology (HR14-022).

  6. Motion of a viscous fluid and a wall in the presence of a stationary wall

    NASA Astrophysics Data System (ADS)

    Sennitskii, V. L.

    2016-03-01

    The problem of damping motion of a hydromechanical system consisting of a viscous fluid and its bounding rigid walls is solved. A condition under which there is an abrupt deceleration of the hydromechanical system is determined.

  7. Rising motion of a bubble layer near a vertical wall

    NASA Astrophysics Data System (ADS)

    Dabiri, Sadegh; Bhuvankar, Pramod

    2015-11-01

    Bubbly flows in vertical pipes and channels form a wall-peak distribution of bubbles under certain conditions. The dynamics of the bubbles near the wall is different than in an unbounded liquid. Here we report the rising motion of bubbles in a liquid near a vertical wall. In a simulation of a bubbly flow in a periodic domain with a vertical wall on one side, an average pressure gradient is applied to the domain that balances the weight of the liquid phase. The upward flow is created by the rising motion of the bubbles. The bubbles are kept near the wall by the lateral lift force acting on them as a result of rising in a shear flow which is in turn generated by rising motion of bubbles. The rise velocity of the bubbles on the wall and the average rise velocity of the liquid depend on three dimensionless parameters, Archimedes number, Eotvos number, and the average volume fraction of bubbles near the wall. In the limit of small Eo, bubbles are nearly spherical and the dependency on Eo becomes negligible. In this limit, the scaling of the liquid Reynolds number with Archimedes number and the void fraction is presented.

  8. Differences in Otolith and Abdominal Viscera Graviceptor Dynamics: Implications for Motion Sickness and Perceived Body Position

    NASA Technical Reports Server (NTRS)

    vonGierke, Henning E.; Parker, Donald E.

    1993-01-01

    Human graviceptors, located in the trunk by Mittelstaedt probably transduce acceleration by abdominal viscera motion. As demonstrated previously in biodynamic vibration and impact tolerance research the thoraco-abdominal viscera exhibit a resonance at 4 to 6 Hz. Behavioral observations and mechanical models of otolith graviceptor response indicate a phase shift increasing with frequency between 0.01 and O.5 Hz. Consequently the potential exists for intermodality sensory conflict between vestibular and visceral graviceptor signals at least at the mechanical receptor level. The frequency range of this potential conflict corresponds with the primary frequency range for motion sickness incidence in transportation, in subjects rotated about Earth-horizontal axes (barbecue spit stimulation) and in periodic parabolic flight microgravity research and also for erroneous perception of vertical oscillations in helicopters. We discuss the implications of this hypothesis for previous self motion perception research and suggestions for various future studies.

  9. Surgical approach to abdominal wall defects: history and new trends.

    PubMed

    Basile, Francesco; Biondi, Antonio; Donati, Marcello

    2013-01-01

    We briefly outline the history of hernia surgery development from the Ebers Papyrus to modern prosthetic repairs. The rapid evolution of anatomical, physiological and pathogenetic concepts has involved the rapid evolution of surgical treatments. From hernia sack cauterization to sack ligation, posterior wall repair (Bassini), and prosthetic reinforcement there has been an evident improvement in surgical treatment results that has stimulated surgeons to find new technical solutions over time. The introduction of prosthetic repair, the laparoscopic revolution, the impact of local anesthesia and the diffusion of day surgery have been the main advances of the last 50 years. Searching for new gold standards, the introduction of new devices has also led to new complications and problems. Research of the last 10 years has been directed to overcome prosthetic repair complications, introducing every year new meshes and materials. Lightweight meshes, composite meshes and biologic meshes are novelties of the last few years. We also take a look at future trends. PMID:24380545

  10. [Impact of abdominoplasty on quality of life in patients, suffering anterior abdominal wall deformity and obesity].

    PubMed

    Dronov, O I; Koval's'ka, I O; Roshchyna, L O; Fedoruk, V I; Burov, E Iu; Fedoruk, P V

    2011-12-01

    The modern tendencies of surgery development include not only the operative procedures improvement but guaranteeing also a maximally high level achievement in the patients quality of life in the early, as well as during remote, postoperative period. The quality of life analysis was done in 132 patients, operated on for the anterior abdominal wall defects, obesity and other surgical diseases, using special questionnaire SF-36. The patients have aged 23-65 years old, in all of them the excessive body mass or obesity of abdominal type was noted. PMID:22432186

  11. Massive Localized Lymphedema Arising from Abdominal Wall: A Case Report and Review of the Literature.

    PubMed

    Tóth, Teodóra; Chang Chien, Yi-Che; Kollár, Sándor; Kovács, Ilona

    2015-01-01

    Massive localized lymphedema (MLL) is a rare pseudosarcomatous lesion due to localized lymphatic obstruction from variable causes. It is most common on medial aspect of thigh and inguinal region. Abdominal localization is rare and may cause clinical diagnostic confusion with other malignant tumors due to its large size. We report a case of abdominal wall MLL of a 56-year-old male patient under clinical suspicion of well differentiated liposarcoma. The literature search and differential diagnosis will be addressed. In doubt cases, immunohistochemical stain or fluorescent in situ hybridization can help to separate this entity from the other mimickers. PMID:26417468

  12. Traumatic disruption of the abdominal wall: lap-belt injuries in children.

    PubMed

    Moremen, Jacob R; Nakayama, Don K; Ashley, Dennis W; Astin, Matthew; Nolan, Tracy L

    2013-04-01

    Traumatic abdominal wall hernia (TAWH) from high speed mechanism is a unique finding in adult trauma, and exceedingly rare in pediatrics. The majority of reports are of low-speed "handlebar" hernias associated with direct injury by bicycle handlebars. We report a series of three pediatric patients in motor vehicle collisions (MVC) who experienced TAWH by lap-belt and associated intra-abdominal injuries necessitating immediate operative intervention. Different operative approaches were used in each case to manage the varying types of disruptions. This adds to the pediatric literature the largest series of its kind. PMID:23583160

  13. Magnetic domain wall motion by spin transfer

    NASA Astrophysics Data System (ADS)

    Grollier, Julie; Chanthbouala, A.; Matsumoto, R.; Anane, A.; Cros, V.; Nguyen van Dau, F.; Fert, Albert

    2011-04-01

    The discovery that a spin polarized current can exert a large torque on a ferromagnet through a transfusion of spin angular momentum, offers a new way to control a magnetization by simple current injection, without the help of an applied external field. Spin transfer can be used to induce magnetization reversals and oscillations, or to control the position of a magnetic domain wall. In this review, we focus on this last mechanism, which is today the subject of an extensive research, both because the microscopic details for its origin are still debated, but also because promising applications are at stake for non-volatile magnetic memories.

  14. Clinical Application of a Silk Fibroin Protein Biologic Scaffold for Abdominal Wall Fascial Reinforcement

    PubMed Central

    Downey, Susan; Agullo, Frank; Lehfeldt, Max R.; Kind, Gabriel M.; Palladino, Humberto; Marshall, Deirdre; Jewell, Mark L.; Mathur, Anshu B.; Bengtson, Bradley P.

    2014-01-01

    Background: Preclinical studies have demonstrated that macroporous silk fibroin protein scaffolds are capable of promoting physiologically durable supportive tissue, which favors application of these engineered tissues for clinical implantation. The safety and effectiveness of a long-lasting, transitory, 510(k)-cleared purified silk fibroin biologic scaffold (SBS) are investigated for soft-tissue support and repair of the abdominal wall. Methods: We conducted a multicenter retrospective review of all consecutive patients who underwent abdominal wall soft-tissue reinforcement with an SBS device between 2011 and 2013. Indications, comorbid conditions, surgical technique, complications, and outcomes were evaluated. Results: We reviewed the records of 172 consecutive patients who received an SBS for soft-tissue support. Of those, 77 patients underwent abdominal wall fascial repair, with a mean follow-up of 18.4 ± 7.5 months. Procedures using an SBS included reinforcement of an abdominal-based flap donor site (31.2%), ventral hernia repair (53.2%), and abdominoplasty (15.6%). The overall complication rate was 6.5%, consisting of 2 wound dehiscences, 1 with device exposure, 1 seroma, 1 infection with explantation, and a perioperative bulge requiring reoperation. There were no reports of hernia. Conclusions: Postoperative complication rates after 18 months were low, and most surgical complications were managed nonoperatively on an outpatient basis without mesh removal. To our knowledge, this is the only series to report on a long-lasting, transitory SBS for abdominal wall repair and reinforcement. Procedure-specific outcome studies are warranted to delineate optimal patient selection and define potential device characteristic advantages. PMID:25506529

  15. Effect of Audio Coaching on Correlation of Abdominal Displacement With Lung Tumor Motion

    SciTech Connect

    Nakamura, Mitsuhiro Narita, Yuichiro; Matsuo, Yukinori; Narabayashi, Masaru; Nakata, Manabu; Sawada, Akira; Mizowaki, Takashi; Nagata, Yasushi; Hiraoka, Masahiro

    2009-10-01

    Purpose: To assess the effect of audio coaching on the time-dependent behavior of the correlation between abdominal motion and lung tumor motion and the corresponding lung tumor position mismatches. Methods and Materials: Six patients who had a lung tumor with a motion range >8 mm were enrolled in the present study. Breathing-synchronized fluoroscopy was performed initially without audio coaching, followed by fluoroscopy with recorded audio coaching for multiple days. Two different measurements, anteroposterior abdominal displacement using the real-time positioning management system and superoinferior (SI) lung tumor motion by X-ray fluoroscopy, were performed simultaneously. Their sequential images were recorded using one display system. The lung tumor position was automatically detected with a template matching technique. The relationship between the abdominal and lung tumor motion was analyzed with and without audio coaching. Results: The mean SI tumor displacement was 10.4 mm without audio coaching and increased to 23.0 mm with audio coaching (p < .01). The correlation coefficients ranged from 0.89 to 0.97 with free breathing. Applying audio coaching, the correlation coefficients improved significantly (range, 0.93-0.99; p < .01), and the SI lung tumor position mismatches became larger in 75% of all sessions. Conclusion: Audio coaching served to increase the degree of correlation and make it more reproducible. In addition, the phase shifts between tumor motion and abdominal displacement were improved; however, all patients breathed more deeply, and the SI lung tumor position mismatches became slightly larger with audio coaching than without audio coaching.

  16. Fluid-structure interaction in abdominal aortic aneurysms: effects of asymmetry and wall thickness

    PubMed Central

    Scotti, Christine M; Shkolnik, Alexander D; Muluk, Satish C; Finol, Ender A

    2005-01-01

    Background Abdominal aortic aneurysm (AAA) is a prevalent disease which is of significant concern because of the morbidity associated with the continuing expansion of the abdominal aorta and its ultimate rupture. The transient interaction between blood flow and the wall contributes to wall stress which, if it exceeds the failure strength of the dilated arterial wall, will lead to aneurysm rupture. Utilizing a computational approach, the biomechanical environment of virtual AAAs can be evaluated to study the affects of asymmetry and wall thickness on this stress, two parameters that contribute to increased risk of aneurysm rupture. Methods Ten virtual aneurysm models were created with five different asymmetry parameters ranging from β = 0.2 to 1.0 and either a uniform or variable wall thickness to study the flow and wall dynamics by means of fully coupled fluid-structure interaction (FSI) analyses. The AAA wall was designed to have a (i) uniform 1.5 mm thickness or (ii) variable thickness ranging from 0.5 – 1.5 mm extruded normally from the boundary surface of the lumen. These models were meshed with linear hexahedral elements, imported into a commercial finite element code and analyzed under transient flow conditions. The method proposed was then compared with traditional computational solid stress techniques on the basis of peak wall stress predictions and cost of computational effort. Results The results provide quantitative predictions of flow patterns and wall mechanics as well as the effects of aneurysm asymmetry and wall thickness heterogeneity on the estimation of peak wall stress. These parameters affect the magnitude and distribution of Von Mises stresses; varying wall thickness increases the maximum Von Mises stress by 4 times its uniform thickness counterpart. A pre-peak systole retrograde flow was observed in the AAA sac for all models, which is due to the elastic energy stored in the compliant arterial wall and the expansion force of the artery

  17. Abdominal Wall Endometriosis Excision with Mesh Closure - Report of Two Cases.

    PubMed

    Vaz-de-Macedo, Carolina; Gomes-da-Costa, Ana; Mendes, Sofia; Barata, Sónia; Alho, Conceição; Jorge, Carlos Calhaz; Osório, Filipa

    2016-04-01

    Abdominal wall endometriosis (AWE) is a rare condition included in the differential diagnosis of an abdominal wall mass and/or pelvic pain in women of reproductive age. It usually occurs after pelvic surgery, most commonly caesarean section. Given the variable clinical presentation, diagnosis can be challenging if a high index of suspicion for AWE does not exist. Consequently, the correct diagnosis is often missed in the preoperative assessment. The presence of endometriosis in other locations can aid in the diagnosis, but other endometriotic lesions do not always exist. Image studies, particularly ultrasound and magnetic resonance imaging, can also be of help in the differential diagnosis. Even though new management techniques such as ultrasound-guided percutaneous cryoablation seem to be promising, surgical excision is still the mainstay of treatment. When the aponeurosis is involved, lesion excision might need to be followed by wall closure with the use of a mesh to lessen tissue tension. We present two typical cases of AWE after caesarean section, one of them recurrent, in patients with concurrent endometriosis of other locations. Total lesion excision followed by polypropylene mesh closure has been performed, with very good post-operative outcomes. We aim to raise awareness towards this diagnosis and to highlight the importance of complete lesion excision and adequate closure of the abdominal wall. PMID:27042795

  18. Histological characteristics of the abdominal aortic wall in patients with vascular chronic Q fever

    PubMed Central

    Hagenaars, Julia C J P; Koning, Olivier H J; van den Haak, Ronald F F; Verhoeven, Bart A N; Renders, Nicole H M; Hermans, Mirjam H A; Wever, Peter C; van Suylen, Robert Jan

    2014-01-01

    The aim of this study was to describe specific histological findings of the Coxiella burnetii-infected aneurysmal abdominal aortic wall. Tissue samples of the aneurysmal abdominal aortic wall from seven patients with chronic Q fever and 15 patients without evidence of Q fever infection were analysed and compared. Chronic Q fever was diagnosed using serology and tissue PCR analysis. Histological sections were stained using haematoxylin and eosin staining, Elastica van Gieson staining and immunohistochemical staining for macrophages (CD68), T lymphocytes (CD3), T lymphocyte subsets (CD4 and CD8) and B lymphocytes (CD20). Samples were scored by one pathologist, blinded for Q fever status, using a standard score form. Seven tissue samples from patients with chronic Q fever and 15 tissue samples from patients without Q fever were collected. Four of seven chronic Q fever samples showed a necrotizing granulomatous response of the vascular wall, which was characterized by necrotic core of the arteriosclerotic plaque (P = 0.005) and a presence of high numbers of macrophages in the adventitia (P = 0.007) distributed in typical palisading formation (P = 0.005) and surrounded by the presence of high numbers of T lymphocytes located diffusely in media and adventitia. Necrotizing granulomas are a histological finding in the C. burnetii-infected aneurysmal abdominal aortic wall. Chronic Q fever should be included in the list of infectious diseases with necrotizing granulomatous response, such as tuberculosis, cat scratch disease and syphilis. PMID:24953727

  19. Histological characteristics of the abdominal aortic wall in patients with vascular chronic Q fever.

    PubMed

    Hagenaars, Julia C J P; Koning, Olivier H J; van den Haak, Ronald F F; Verhoeven, Bart A N; Renders, Nicole H M; Hermans, Mirjam H A; Wever, Peter C; van Suylen, Robert Jan

    2014-08-01

    The aim of this study was to describe specific histological findings of the Coxiella burnetii-infected aneurysmal abdominal aortic wall. Tissue samples of the aneurysmal abdominal aortic wall from seven patients with chronic Q fever and 15 patients without evidence of Q fever infection were analysed and compared. Chronic Q fever was diagnosed using serology and tissue PCR analysis. Histological sections were stained using haematoxylin and eosin staining, Elastica van Gieson staining and immunohistochemical staining for macrophages (CD68), T lymphocytes (CD3), T lymphocyte subsets (CD4 and CD8) and B lymphocytes (CD20). Samples were scored by one pathologist, blinded for Q fever status, using a standard score form. Seven tissue samples from patients with chronic Q fever and 15 tissue samples from patients without Q fever were collected. Four of seven chronic Q fever samples showed a necrotizing granulomatous response of the vascular wall, which was characterized by necrotic core of the arteriosclerotic plaque (P = 0.005) and a presence of high numbers of macrophages in the adventitia (P = 0.007) distributed in typical palisading formation (P = 0.005) and surrounded by the presence of high numbers of T lymphocytes located diffusely in media and adventitia. Necrotizing granulomas are a histological finding in the C. burnetii-infected aneurysmal abdominal aortic wall. Chronic Q fever should be included in the list of infectious diseases with necrotizing granulomatous response, such as tuberculosis, cat scratch disease and syphilis. PMID:24953727

  20. Current induced domain wall motion: Analysis and simulation

    NASA Astrophysics Data System (ADS)

    Yang, Lei

    The subject of current induced magnetic reversal has received considerable interest recently due to its attractive property for magnetic nanodevice applications. In this thesis, 3D simulations are performed to study current induced magnetic domain motion in magnetic nanostrips and nanowires based on the Landau-Lifshitz-Gilbert model with a spin transfer torque. For sufficiently thin strips and wires, the LLG equation can be reduced to a one dimensional model. For the simplified models, the dynamic laws for the domain wall motion are derived from a matched asymptotic expansion. The results are consistent with the numerical results. We also study the current induced magnetic domain wall motion in magnetic nanostrips with defects. Our numerical results show that when a domain wall passes through a defect, it experiences a strong attracting force. There is a critical current density below which the domain wall will oscillate around the defect and eventually be pinned at the defect. From the asymptotic expansion analysis, we show that the amplitude of this domain wall oscillation can be resonantly amplified by an ac current with proper frequency for the first time. This suggests a way to reduce the critical current for depinning of the domain wall.

  1. A Large Single-Center Experience of Open Lateral Abdominal Wall Hernia Repairs.

    PubMed

    Patel, Puraj P; Warren, Jeremy A; Mansour, Roozbeh; Cobb, William S; Carbonell, Alfredo M

    2016-07-01

    Lateral abdominal wall hernias may occur after a variety of procedures, including anterior spine exposure, urologic procedures, ostomy closures, or after trauma. Anatomically, these hernias are challenging and require a complete understanding of abdominal wall, interparietal and retroperitoneal, anatomy for successful repair. Mesh placement requires extensive dissection of often unfamiliar planes, and its fixation is difficult. We report our experience with open mesh repair of lateral abdominal wall hernias. A retrospective review of a prospectively maintained database was performed to identify patients with a classification of lateral abdominal wall hernia who underwent an open repair. A total of 61 patients underwent open lateral hernia repairs. Mean patient age was 58 years (range 25-78), with a mean body mass index of 32 kg/m(2) (range 19.0-59.1). According to the European Hernia Society classification, defects were located subcostal (L1, 14 patients), flank (L2, 33 patients), iliac (L3, 11 patients), and lumber (L4, 3 patients). Mean defect size was 78.6 cm(2), with a mean greatest single dimension of 9.2 cm (range 2-25 cm). Retromuscular or interparietal repair was performed in 50.8 per cent, preperitoneal in 41.0 per cent, intraperitoneal in 6.6 per cent, and onlay in 1.6 per cent. The rate of surgical site occurrence was 49.2 per cent, primarily seroma and surgical site infection rate was 13.1 per cent. With a mean follow-up of 15.4 months, seven patients (11.5%) have documented recurrence. Synthetic mesh reconstruction of lateral wall hernias is challenging. Our experience demonstrates the safety and success of repair using synthetic mesh primarily in the retromuscular, interparietal, or preperitoneal planes. PMID:27457859

  2. Abdominal Wall Endometriosis on the Right Port Site After Laparoscopy: Case Report and Literature Review

    PubMed Central

    Cozzolino, Mauro; Magnolfi, Stefania; Corioni, Serena; Moncini, Daniela; Mattei, Alberto

    2015-01-01

    Background Endometriosis can be intrapelvic or, rarely, extrapelvic. Endometriosis involving the rectus abdominis muscle on the trocar port site is a rare event; until now, only 16 cases have been reported in the literature. The majority of cases were associated with previous abdominal surgery such as diagnostic laparoscopy, cyst excision, appendectomy, myomectomy, or cholecystectomy. We review all the reported cases of this unusual form of extrapelvic endometriosis. Case Report We report a new case of abdominal wall endometriosis at the trocar port site in the rectus abdominis muscle in a woman who had undergone 2 laparoscopies for endometriosis in the 3 years before coming to our attention. The diagnosis was made by sonography. We performed a surgical resection of the lesion with a free macroscopic margin of 5-10 mm. Conclusion Endometriosis should be considered in the differential diagnosis of any abdominal swelling. In our experience, surgery is the treatment of choice. PMID:26412997

  3. Automated Delineation of Vessel Wall and Thrombus Boundaries of Abdominal Aortic Aneurysms Using Multispectral MR Images

    PubMed Central

    Rodriguez-Vila, B.; Tarjuelo-Gutierrez, J.; Sánchez-González, P.; Verbrugghe, P.; Fourneau, I.; Maleux, G.; Herijgers, P.; Gomez, E. J.

    2015-01-01

    A correct patient-specific identification of the abdominal aortic aneurysm is useful for both diagnosis and treatment stages, as it locates the disease and represents its geometry. The actual thickness and shape of the arterial wall and the intraluminal thrombus are of great importance when predicting the rupture of the abdominal aortic aneurysms. The authors describe a novel method for delineating both the internal and external contours of the aortic wall, which allows distinguishing between vessel wall and intraluminal thrombus. The method is based on active shape model and texture statistical information. The method was validated with eight MR patient studies. There was high correspondence between automatic and manual measurements for the vessel wall area. Resulting segmented images presented a mean Dice coefficient with respect to manual segmentations of 0.88 and a mean modified Hausdorff distance of 1.14 mm for the internal face and 0.86 and 1.33 mm for the external face of the arterial wall. Preliminary results of the segmentation show high correspondence between automatic and manual measurements for the vessel wall and thrombus areas. However, since the dataset is small the conclusions cannot be generalized. PMID:26236390

  4. Ferroelectric domain wall motion induced by polarized light.

    PubMed

    Rubio-Marcos, Fernando; Del Campo, Adolfo; Marchet, Pascal; Fernández, Jose F

    2015-01-01

    Ferroelectric materials exhibit spontaneous and stable polarization, which can usually be reoriented by an applied external electric field. The electrically switchable nature of this polarization is at the core of various ferroelectric devices. The motion of the associated domain walls provides the basis for ferroelectric memory, in which the storage of data bits is achieved by driving domain walls that separate regions with different polarization directions. Here we show the surprising ability to move ferroelectric domain walls of a BaTiO₃ single crystal by varying the polarization angle of a coherent light source. This unexpected coupling between polarized light and ferroelectric polarization modifies the stress induced in the BaTiO₃ at the domain wall, which is observed using in situ confocal Raman spectroscopy. This effect potentially leads to the non-contact remote control of ferroelectric domain walls by light. PMID:25779918

  5. Ferroelectric domain wall motion induced by polarized light

    PubMed Central

    Rubio-Marcos, Fernando; Del Campo, Adolfo; Marchet, Pascal; Fernández, Jose F.

    2015-01-01

    Ferroelectric materials exhibit spontaneous and stable polarization, which can usually be reoriented by an applied external electric field. The electrically switchable nature of this polarization is at the core of various ferroelectric devices. The motion of the associated domain walls provides the basis for ferroelectric memory, in which the storage of data bits is achieved by driving domain walls that separate regions with different polarization directions. Here we show the surprising ability to move ferroelectric domain walls of a BaTiO3 single crystal by varying the polarization angle of a coherent light source. This unexpected coupling between polarized light and ferroelectric polarization modifies the stress induced in the BaTiO3 at the domain wall, which is observed using in situ confocal Raman spectroscopy. This effect potentially leads to the non-contact remote control of ferroelectric domain walls by light. PMID:25779918

  6. Development of a novel synthetic material to close abdominal wall defects.

    PubMed

    Cnota, M A; Aliabadi-Wahle, S; Choe, E U; Jacob, J T; Flint, L M; Ferrara, J J

    1998-05-01

    To compare the efficacy of a novel synthetic material (TMS-2) with polytetrafluoroethylene, polypropylene (Marlex), and primary closure of experimentally fashioned clean and contaminated abdominal wounds, 1-cm2 abdominal wall defects were created in each of the four abdominal quadrants of rats (n = 10). Patches of each material were used to repair three of these defects, the fourth being primarily closed. A second group of rats (n = 7) underwent the same operative protocol; however, peritonitis was induced at the time of surgery using a fecal inoculation technique. Animals were killed 2 weeks later, and surface area and severity of formed adhesions were assessed by a "blinded" observer. All closure techniques were successful insofar as none demonstrated fascial dehiscence. Compared with each synthetic material, the surface area of formed adhesions was smaller after primary closure in clean and in contaminated conditions; however, the three synthetic materials were equally matched regarding surface area of adhesions under both conditions. In the face of fecal contamination, TMS-2 proved identical to primary closure, each generating significantly (P < 0.02) milder adhesions than the other prosthetic materials. It is concluded that the TMS-2 may prove of clinical benefit to repair abdominal wall defects. PMID:9585774

  7. The relationship between wall shear stress distributions and intimal thickening in the human abdominal aorta

    PubMed Central

    Bonert, Michael; Leask, Richard L; Butany, Jagdish; Ethier, C Ross; Myers, Jerry G; Johnston, K Wayne; Ojha, Matadial

    2003-01-01

    Purpose The goal of this work was to determine wall shear stress (WSS) patterns in the human abdominal aorta and to compare these patterns to measurements of intimal thickness (IT) from autopsy samples. Methods The WSS was experimentally measured using the laser photochromic dye tracer technique in an anatomically faithful in vitro model based on CT scans of the abdominal aorta in a healthy 35-year-old subject. IT was quantified as a function of circumferential and axial position using light microscopy in ten human autopsy specimens. Results The histomorphometric analysis suggests that IT increases with age and that the distribution of intimal thickening changes with age. The lowest WSS in the flow model was found on the posterior wall inferior to the inferior mesenteric artery, and coincided with the region of most prominent IT in the autopsy samples. Local geometrical features in the flow model, such as the expansion at the inferior mesenteric artery (common in younger individuals), strongly influenced WSS patterns. The WSS was found to correlate negatively with IT (r2 = 0.3099; P = 0.0047). Conclusion Low WSS in the abdominal aorta is co-localized with IT and may be related to atherogenesis. Also, rates of IT in the abdominal aorta are possibly influenced by age-related geometrical changes. PMID:14641919

  8. A comparison of prosthetic materials used to repair abdominal wall defects.

    PubMed

    Mori, N; Takano, K; Miyake, T; Nishio, T; Muto, S; Koshizuka, K; Nakagomi, H; Kubo, M; Tada, Y

    1998-09-01

    Large abdominal wall defects may require a prosthesis for closure. The aim of our study was to identify the best material for abdominoplasty in pediatric patients. One hundred twenty-eight Wistar KY strain male rats (3 weeks old) were used. All animals underwent celiotomy via a midline skin incision. They were divided into seven groups as follows: the animals in groups 1 through 6 underwent full-thickness abdominal wall excision 3 cm in diameter. The animals in group 1 underwent primary closure. In groups 2 through 6 the defect was closed with prosthetic material. In Group 7, a sham operation was performed. Daily weights were measured. The animals were killed after 3 and 9 weeks. Adhesion scores were assigned for each group. Vicryl mesh resulted in the fewest adhesions and had no effect on weight gain in the developing rats. PMID:9716675

  9. Desmoid tumor of the anterior abdominal wall in female patients: comparison with endometriosis.

    PubMed

    Krentel, H; Tchartchian, G; De Wilde, R L

    2012-01-01

    In female patients presenting a tumor of the lower abdominal wall especially after cesarian section, an endometriotic tumor as well as an aggressive desmoid tumor should be considered. Symptoms in correlation with the monthly period can facilitate the presurgical differentiation between endometriosis and fibromatosis. Ultrasound reveals the typical location of both tumors and its remarkable sonographic appearance. In the clinical practice, the desmoid fibromatosis of the lower abdominal wall is a very rare disease. We present a case of a 25-year-old pregnant and discuss diagnostic and therapeutic options by a PubMed literature review. With the knowledge of the prognosis of the desmoid fibromatosis and the respective treatment options including wait and see, complete surgical resection with macroscopically free margins and adjuvant approaches is essential to avoid further interventions and progression of the locally destructive tumor. PMID:22778752

  10. Desmoid Tumor of the Anterior Abdominal Wall in Female Patients: Comparison with Endometriosis

    PubMed Central

    Krentel, H.; Tchartchian, G.; De Wilde, R. L.

    2012-01-01

    In female patients presenting a tumor of the lower abdominal wall especially after cesarian section, an endometriotic tumor as well as an aggressive desmoid tumor should be considered. Symptoms in correlation with the monthly period can facilitate the presurgical differentiation between endometriosis and fibromatosis. Ultrasound reveals the typical location of both tumors and its remarkable sonographic appearance. In the clinical practice, the desmoid fibromatosis of the lower abdominal wall is a very rare disease. We present a case of a 25-year-old pregnant and discuss diagnostic and therapeutic options by a PubMed literature review. With the knowledge of the prognosis of the desmoid fibromatosis and the respective treatment options including wait and see, complete surgical resection with macroscopically free margins and adjuvant approaches is essential to avoid further interventions and progression of the locally destructive tumor. PMID:22778752

  11. Laparoscopic drainage of abdominal wall abscess from spilled stones post-cholecystectomy

    PubMed Central

    Chong, Vincent; Ram, Rishi

    2015-01-01

    We present a case on abdominal wall abscess from spilled stones post-cholecystectomy and describe laparoscopic drainage as our choice of management. Mr M is a 75-year-old male who presented on multiple occasions to the hospital with right upper quadrant pain and fever post-laparoscopic cholecystectomy. He also required multiple courses of antibiotics. Subsequent computed tomography and magnetic resonance imaging scan confirmed a number of retained stone with signs of chronic inflammation. Hence, 6 months after his initial laparoscopic cholecystectomy, he proceeded to an exploratory laparoscopy. We found an abscess cavity measuring 3 × 4 cm over the anterior abdominal wall. The cavity was de-roofed, drained and washed out. The tissue culture grew Klebsiella pneumoniae. Laparoscopic approach is optimal as the abscess cavity can be clearly identified, stones visualized and removed under direct vision. Patient does not require a laparotomy. PMID:26183574

  12. The Use of an Anterior Abdominal Wall Peritoneal Flap in the Laparoscopic Repair of Vesicouterine Fistula

    PubMed Central

    Tasdemir, Nicel; Abali, Remzi; Celik, Cem; Yazici, Cenk Murat; Akkus, Didem

    2014-01-01

    Vesicouterine fistula (VUF) is a rare type of genitourinary fistula. Lower-segment cesarean section is the leading cause of VUF. Patients mostly present with the classical triad of menouria, amenorrhea, and urinary incontinence, with the history of a previous cesarean section. Conservative management with catheterization and open, laparoscopic, and robotic surgeries are the prescribed treatment options. We present the case of a 35-year-old woman who presented with cyclical menouria and urinary incontinence. After diagnosis of VUF by cystoscopy, the laparoscopic approach was chosen. During the procedure, we used anterior abdominal wall peritoneum and adjacent adipose tissue interposition for the first time, instead of omental interposition, because of the unavailability of omentum. The postoperative period was uneventful, and the procedure was successful. In conclusion, the laparoscopic approach is feasible and the anterior abdominal wall peritoneal flap can be used instead of omentum for tissue interposition when the omentum is not available. PMID:25216441

  13. Current practice of abdominal wall closure in elective surgery – Is there any consensus?

    PubMed Central

    Rahbari, Nuh N; Knebel, Phillip; Diener, Markus K; Seidlmayer, Christoph; Ridwelski, Karsten; Stöltzing, Hartmut; Seiler, Christoph M

    2009-01-01

    Background Development of incisional hernia after open abdominal surgery remains a major cause of post-operative morbidity. The aim of this study was to determine the current practice of surgeons in terms of access to and closure of the abdominal cavity in elective open surgery. Methods Twelve surgical departments of the INSECT-Trial group documented the following variables for 50 consecutive patients undergoing abdominal surgery: fascial closure techniques, applied suture materials, application of subcutaneous sutures, subcutaneous drains, methods for skin closure. Descriptive analysis was performed and consensus of treatment variables was categorized into four levels: Strong consensus >95%, consensus 75–95%, overall agreement 50–75%, no consensus <50%. Results 157 out of 599 patients were eligible for analysis (85 (54%) midline, 54 (35%) transverse incisions). After midline incisions the fascia was closed continuously in 55 patients (65%), using slowly absorbable (n = 47, 55%), braided (n = 32, 38%) sutures with a strength of 1 (n = 48, 57%). In the transverse setting the fascia was closed continuously in 39 patients (72%) with slowly absorbable (n = 22, 41%) braided sutures (n = 27, 50%) with a strength of 1 (n = 30, 56%). Conclusion In the present evaluation midline incision was the most frequently applied access in elective open abdominal surgery. None of the treatments for abdominal wall closure (except skin closure in the midline group) is performed on a consensus level. PMID:19442311

  14. Lateral Abdominal Wall Defects: The Importance of Anatomy and Technique for a Successful Repair

    PubMed Central

    Pulikkottil, Benson J.; Pezeshk, Ronnie A.; Daniali, Lily N.; Bailey, Steven H.; Mapula, Steven

    2015-01-01

    Summary: Flank and lateral abdominal wall defects can be an extremely challenging phenomenon for surgeons to undertake. Their rarity and specific idiosyncrasies in regard to embryologic and anatomical characteristics must be taken into consideration when formulating an operative plan. We will discuss these cardinal points including technical recommendations by notable experts in the field to gain a better understanding in the diagnosis and treatment of this infrequent but morbid occurrence. PMID:26495194

  15. [Hematoma of the abdominal wall. A case report: pitfall of Seldinger method via femoral artery].

    PubMed

    Hiramatsu, Hisaya; Sugiura, Yasushi; Takeda, Ririko; Nanba, Hiroki

    2009-02-01

    We reported a case of an abdominal wall hematoma which caused by Seldinger method via the femoral artery. A 48-year-old female, suffered from direct carotid cavernous fistula, was treated by transfemoral transvenous embolization (TVE). The whole procedure was completed without difficulty except minor resistance of guide wire manipulation during left femoral artery catheterization. Four hours later, the patient became hypotensive and showed the sign of impending shock without definitive causes. Nine hours after the embolization a huge hematoma of the abdominal wall was found. It required the total 1200 m/ of blood transfusion before her blood pressure returned to normal. She recovered fully from this event and discharged uneventfully. There is a speculation that a deep circumflex iliac artery (DCIA) was injured with an angle-shaped guide wire and bled into the abdominal wall. And subsequent systemic heparinization prevented the coagulation process, resulting a large hematoma. Anatomically, an angle-shaped guide wire is easily able to migrate into DCIA. To prevent a vascular injury, it is very important to manipulate a guide wire under fluoroscopic control and to select a J-shaped guide wire instead of an angle-shaped one. PMID:19227158

  16. The management of abdominal wall hernias – in search of consensus

    PubMed Central

    Bury, Kamil; Śmietański, Maciej

    2015-01-01

    Introduction Laparoscopic repair is becoming an increasingly popular alternative in the treatment of abdominal wall hernias. In spite of numerous studies evaluating this technique, indications for laparoscopic surgery have not been established. Similarly, implant selection and fixation techniques have not been unified and are the subject of scientific discussion. Aim To assess whether there is a consensus on the management of the most common ventral abdominal wall hernias among recognised experts. Material and methods Fourteen specialists representing the boards of European surgical societies were surveyed to determine their choice of surgical technique for nine typical primary ventral and incisional hernias. The access method, type of operation, mesh prosthesis and fixation method were evaluated. In addition to the laparoscopic procedures, the number of tackers and their arrangement were assessed. Results In none of the cases presented was a consensus of experts obtained. Laparoscopic and open techniques were used equally often. Especially in the group of large hernias, decisions on repair methods were characterised by high variability. The technique of laparoscopic mesh fixation was a subject of great variability in terms of both method selection and the numbers of tackers and sutures used. Conclusions Recognised experts have not reached a consensus on the management of abdominal wall hernias. Our survey results indicate the need for further research and the inclusion of large cohorts of patients in the dedicated registries to evaluate the results of different surgical methods, which would help in the development of treatment algorithms for surgical education in the future. PMID:25960793

  17. Excision of the urachal remnant using the abdominal wall-lift laparoscopy: A case report

    PubMed Central

    Kobayashi, Kosuke; Sasaki, Kazuhito; Iijima, Tatsuo; Yoshimi, Fuyo; Nagai, Hideo

    2016-01-01

    Introduction Here, we report the surgical excision of the urachal remnant using the abdominal wall-lift laparoscopy with a camera port in the umbilicus, combined with a small Pfannenstiel incision to optimally treat the bladder apex. Presentation of case A 21-year-old woman presented with periumbilical discharge and pain on urination. Contrast enhanced CT and MRI showed an abscess in the umbilical region that was connected to the bladder via a long tube-like structure. It was diagnosed as an infected urachal sinus. Partial excision of the umbilical fossa followed by dissection of the urachal remnant was easily performed using the abdominal wall-lift laparoscopy from the umbilicus down to the bladder without pneumoperitoneum or additional trocar placement. A Pfannenstiel incision was made above the pubis to get access to the junction between the urachal remnant and the bladder. Under direct vision, we succeeded in accurately dividing the remnant tract, and we adequately closed the bladder opening with absorbable sutures. This method has the advantage of easily closing peritoneal defects after excision of the urachal remnant with direct sutures under a laparoscopic view from the umbilicus. Cosmetic satisfaction was obtained postoperatively. Discussion and conclusion Urachal sinus excision using the abdominal wall-lift laparoscopy seems to surpass the previously reported methods in term of safety, cosmetics, and adequacy of surgical procedures. PMID:27064744

  18. Left ventricle wall motion tracking using curvature properties

    NASA Astrophysics Data System (ADS)

    Chandra, Kambhamettu; Goldgof, Dmitry B.

    1992-06-01

    This paper presents the complete implementation of the new algorithm for tracking points on the left ventricle (LV) surface from volumetric cardiac images. We define the local surface stretching as an additional motion parameter of nonrigid transformation. Stretching is constant at all points on the surface for homothetic motion, or follows a polynomial function of certain order (linear in our implementation) in conformal motion. The wall deformation and correspondence information between successive frames of LV in a heart cycle are considered important in evaluating heart behavior and improved diagnosis. We utilize small motion assumption between consecutive frames, hypothesize all possible correspondences, and compute curvature changes for each hypothesis. The computed curvature change is then compared with the one predicted by conformal motion assumption for hypotheses evaluation. We demonstrate the improved performance of the new algorithm utilizing conformal motion with linear stretching assumption over constant stretching assumption on simulated data. Then, the algorithm is applied to real cardiac (CT) images and the stretching of the LV wall is determined. The data set used in our experiments was provided by Dr. Eric Hoffman at University of Pennsylvania Medical school and consists of 16 volumetric (128 by 128 by 118) images taken through the heart cycle.

  19. Impact of poroelasticity of intraluminal thrombus on wall stress of abdominal aortic aneurysms

    PubMed Central

    2012-01-01

    Background The predictions of stress fields in Abdominal Aortic Aneurysm (AAA) depend on constitutive descriptions of the aneurysm wall and the Intra-luminal Thrombus (ILT). ILT is a porous diluted structure (biphasic solid–fluid material) and its impact on AAA biomechanics is controversially discussed in the literature. Specifically, pressure measurements showed that the ILT cannot protect the wall from the arterial pressure, while other (numerical and experimental) studies showed that at the same time it reduces the stress in the wall. Method To explore this phenomenon further a poroelastic description of the ILT was integrated in Finite Element (FE) Models of the AAA. The AAA model was loaded by a pressure step and a cyclic pressure wave and their transition into wall tension was investigated. To this end ILT’s permeability was varied within a microstructurally motivated range. Results The two-phase model verified that the ILT transmits the entire mean arterial pressure to the wall while, at the same time, it significantly reduces the stress in the wall. The predicted mean stress in the AAA wall was insensitive to the permeability of the ILT and coincided with the results of AAA models using a single-phase ILT description. Conclusion At steady state, the biphasic ILT behaves like a single-phase material in an AAA model. Consequently, computational efficient FE single-phase models, as they have been exclusively used in the past, accurately predict the wall stress in AAA models. PMID:22931215

  20. Detection of electromotive force induced by domain wall motion

    NASA Astrophysics Data System (ADS)

    Beach, Geoffrey

    2010-03-01

    A magnetic domain wall can be displaced by current via the transfer of spin angular momentum from conduction electrons to the local magnetization. The capacity of spin-transfer torque to drive domain wall motion is now well established experimentally and theoretically [1], and is a central topic in the growing field of spintronics. This talk will describe the first experimental evidence [2] that the coupling between spin and charge also works in reverse; namely, that a domain wall driven by a field through a stationary electron gas generates an experimentally-detectible voltage. This new spintronic effect [3] was measured by precisely controlling the motion of a single domain wall in a Permalloy nanowire and isolated from other sources using a field modulation scheme to differentiate between the small domain wall-induced voltage and conventional inductive voltages. The domain wall-induced voltage was found to scale in proportion to the driving field magnitude, and its sign depends only on the direction of domain wall motion. These results are consistent with theoretical predictions [2, 4, 5], and will be discussed in terms of a generalized two-dimensional topological framework [2] capable of treating vortex DWs. [4pt] [1] G.S.D. Beach, M. Tsoi, and J.L. Erskine, J. Magn. Magn. Mater. 320, 1272 (2008). [0pt] [2] S. Yang, G.S.D. Beach, C. Knutson, D. Xiao, Q. Niu, M. Tsoi, and J.L. Erskine, Phys. Rev. Lett. 102, 067201 (2009). [0pt] [3]. R. McMichael, and M. Stiles, Physics 2, 11 (2009). [0pt] [4] L. Berger, Phys. Rev. B 33, 1572 (1986) [0pt] [5] S. E. Barnes and S. Maekawa, Appl. Phys. 89, 122507 (2006).

  1. Planning 4-Dimensional Computed Tomography (4DCT) Cannot Adequately Represent Daily Intrafractional Motion of Abdominal Tumors

    SciTech Connect

    Ge, Jiajia; Santanam, Lakshmi; Noel, Camille; Parikh, Parag J.

    2013-03-15

    Purpose: To evaluate whether planning 4-dimensional computed tomography (4DCT) can adequately represent daily motion of abdominal tumors in regularly fractionated and stereotactic body radiation therapy (SBRT) patients. Methods and Materials: Intrafractional tumor motion of 10 patients with abdominal tumors (4 pancreas-fractionated and 6 liver-stereotactic patients) with implanted fiducials was measured based on daily orthogonal fluoroscopic movies over 38 treatment fractions. The needed internal margin for at least 90% of tumor coverage was calculated based on a 95th and fifth percentile of daily 3-dimensional tumor motion. The planning internal margin was generated by fusing 4DCT motion from all phase bins. The disagreement between needed and planning internal margin was analyzed fraction by fraction in 3 motion axes (superior-inferior [SI], anterior-posterior [AP], and left-right [LR]). The 4DCT margin was considered as an overestimation/underestimation of daily motion when disagreement exceeded at least 3 mm in the SI axis and/or 1.2 mm in the AP and LR axes (4DCT image resolution). The underlying reasons for this disagreement were evaluated based on interfractional and intrafractional breathing variation. Results: The 4DCT overestimated daily 3-dimensional motion in 39% of the fractions in 7 of 10 patients and underestimated it in 53% of the fractions in 8 of 10 patients. Median underestimation was 3.9 mm, 3.0 mm, and 1.7 mm in the SI axis, AP axis, and LR axis, respectively. The 4DCT was found to capture irregular deep breaths in 3 of 10 patients, with 4DCT motion larger than mean daily amplitude by 18 to 21 mm. The breathing pattern varied from breath to breath and day to day. The intrafractional variation of amplitude was significantly larger than intrafractional variation (2.7 mm vs 1.3 mm) in the primary motion axis (ie, SI axis). The SBRT patients showed significantly larger intrafractional amplitude variation than fractionated patients (3.0 mm vs 2

  2. Adipocyte in vascular wall can induce the rupture of abdominal aortic aneurysm

    PubMed Central

    Kugo, Hirona; Zaima, Nobuhiro; Tanaka, Hiroki; Mouri, Youhei; Yanagimoto, Kenichi; Hayamizu, Kohsuke; Hashimoto, Keisuke; Sasaki, Takeshi; Sano, Masaki; Yata, Tatsuro; Urano, Tetsumei; Setou, Mitsutoshi; Unno, Naoki; Moriyama, Tatsuya

    2016-01-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving the gradual dilation of the abdominal aorta. It has been reported that development of AAA is associated with inflammation of the vascular wall; however, the mechanism of AAA rupture is not fully understood. In this study, we investigated the mechanism underlying AAA rupture using a hypoperfusion-induced animal model. We found that the administration of triolein increased the AAA rupture rate in the animal model and that the number of adipocytes was increased in ruptured vascular walls compared to non-ruptured walls. In the ruptured group, macrophage infiltration and the protein levels of matrix metalloproteinases 2 and 9 were increased in the areas around adipocytes, while collagen-positive areas were decreased in the areas with adipocytes compared to those without adipocytes. The administration of fish oil, which suppresses adipocyte hypertrophy, decreased the number and size of adipocytes, as well as decreased the risk of AAA rupture ratio by 0.23 compared to the triolein administered group. In human AAA samples, the amount of triglyceride in the adventitia was correlated with the diameter of the AAA. These results suggest that AAA rupture is related to the abnormal appearance of adipocytes in the vascular wall. PMID:27499372

  3. Adipocyte in vascular wall can induce the rupture of abdominal aortic aneurysm.

    PubMed

    Kugo, Hirona; Zaima, Nobuhiro; Tanaka, Hiroki; Mouri, Youhei; Yanagimoto, Kenichi; Hayamizu, Kohsuke; Hashimoto, Keisuke; Sasaki, Takeshi; Sano, Masaki; Yata, Tatsuro; Urano, Tetsumei; Setou, Mitsutoshi; Unno, Naoki; Moriyama, Tatsuya

    2016-01-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving the gradual dilation of the abdominal aorta. It has been reported that development of AAA is associated with inflammation of the vascular wall; however, the mechanism of AAA rupture is not fully understood. In this study, we investigated the mechanism underlying AAA rupture using a hypoperfusion-induced animal model. We found that the administration of triolein increased the AAA rupture rate in the animal model and that the number of adipocytes was increased in ruptured vascular walls compared to non-ruptured walls. In the ruptured group, macrophage infiltration and the protein levels of matrix metalloproteinases 2 and 9 were increased in the areas around adipocytes, while collagen-positive areas were decreased in the areas with adipocytes compared to those without adipocytes. The administration of fish oil, which suppresses adipocyte hypertrophy, decreased the number and size of adipocytes, as well as decreased the risk of AAA rupture ratio by 0.23 compared to the triolein administered group. In human AAA samples, the amount of triglyceride in the adventitia was correlated with the diameter of the AAA. These results suggest that AAA rupture is related to the abnormal appearance of adipocytes in the vascular wall. PMID:27499372

  4. The occurrence of an abdominal wall abscess 11 years after appendectomy: report of a case.

    PubMed

    Matsuda, K; Masaki, T; Toyoshima, O; Ono, M; Muto, T

    1999-01-01

    Most complications after appendectomy occur within 10 days; however, we report herein the unusual case of a patient in whom a wound abscess was detected more than 10 years after an appendectomy. A 26-year-old woman presented to our hospital with nausea and vomiting, pain, and a mass in the right lower abdominal wall. She had undergone an appendectomy 11 years previously. Physical examination revealed a tender mass, 5 cm in diameter, under the appendectomy scar. An abdominal ultrasonography demonstrated a low-echoic mass lesion measuring 9.0 x 5.0 x 2.0 cm. Incision of the connective tissue revealed about 3 ml of cream-colored and odorless fluid in the abscess cavity. Fistulography revealed an abscess cavity not communicating with the bowel lumen. Floss was discovered in the connective tissue and removed. Debridement of the abscess wall was performed and a piece of the wall was sent for histologic examination. Pathological examination revealed panniculitis of the subcutaneous tissue, and panniculitis with granulation and granuloma of the abscess wall. This case report demonstrates that a preoperative diagnosis should be based not on one finding, but on all findings collected, inclusively. PMID:10489140

  5. Respiratory kinematics by optoelectronic analysis of chest-wall motion and ultrasonic imaging of the diaphragm

    NASA Astrophysics Data System (ADS)

    Aliverti, Andrea; Pedotti, Antonio; Ferrigno, Giancarlo; Macklem, P. T.

    1998-07-01

    Although from a respiratory point of view, compartmental volume change or lack of it is the most crucial variable, it has not been possible to measure the volume of chest wall compartments directly. Recently we developed a new method based on a optoelectronic motion analyzer that can give the three-dimensional location of many markers with the temporal and spatial accuracy required for respiratory measurements. Marker's configuration has been designed specifically to measure the volume of three chest wall compartments, the pulmonary and abdominal rib cage compartments and the abdomen, directly. However, it can not track the exact border between the two rib cage compartments (pulmonary and abdominal) which is determined by the cephalic extremity of the area of apposition of the diaphragm to the inner surface of the rib cage, and which can change systematically as a result of disease processes. The diaphragm displacement can be detected by ultrasonography. In the present study, we propose an integrated system able to investigate the relationships between external (chest wall) and internal (diaphragm) movements of the different respiratory structures by simultaneous external imaging with the optoelectronic system combined with internal kinematic imaging using ultrasounds. 2D digitized points belonging to the lower lung margin, taken from ultrasonographic views, are mapped into the 3D space, where chest wall markers are acquired. Results are shown in terms of accuracy of 3D probe location, relative movement between the probe and the body landmarks, dynamic relationships between chest wall volume and position of the diaphragm during quiet breathing, slow inspirations, relaxations and exercise.

  6. Novel Technique for Innervated Abdominal Wall Vascularized Composite Allotransplantation: A Separation of Components Approach

    PubMed Central

    Mavrophilipos, Vasilios D.; Zapora, Jeffrey A.; Berli, Jens; Broyles, Justin; Chopra, Karan; Sabino, Jennifer; Matthews, Jamil; Buckingham, E. Bryan; Maddox, John S.; Bluebond-Langner, Rachel; Silverman, Ronald P.

    2014-01-01

    Objective: Applications for Abdominal Wall Vascularized Composite Allotransplantation may expand if a functional graft with decreased immunosuppressive requirements can be designed. We hypothesize that it is anatomically feasible to prepare a functional, innervated, and vascularized abdominal composite graft using a multilayered component separation technique. Including vascularized bone in the graft design may decrease the immunosuppressive requirements by inducing immunologic chimerism. Methods: Two cadaver torsos were used. Adipocutaneous flaps were elevated from the midaxillary lines, preserving deep inferior epigastric artery perforators. A 2-layered component separation through the external and internal oblique fasciae was carried out, exposing segmental intercostal thoracolumbar nerves. Superiorly directed muscle release over the subcostal margin provided for a 3-rib segment with attached rectus abdominis muscle. The remainder of the full-thickness allograft was harvested with its vasculature. Flap inset into the recipient cadaver abdomen, with osteosynthesis fixation between donor and recipient ribs, was achieved. Results: The harvested grafts had an average size of 845 ± 205 cm2 with a total procurement time of 110 minutes. On one cadaver, 4 thoracolumbar nerves were isolated bilaterally, while the other cadaver yielded 3 nerves. The nerves were transected with an average length of 5.7 ± 1.2 cm. The graft vasculature was transected with a length of 4.40 ± 0.10 cm. Conclusion: Using the principles of component separation technique, we demonstrated a novel approach to harvest and transfer a neurotized osteomyofasciocutaneous abdominal wall allotransplant as a multipedicled, single functional unit. PMID:25328567

  7. Domain-wall motion in random potential and hysteresis modeling

    SciTech Connect

    Pasquale, M.; Basso, V.; Bertotti, G.; Jiles, D.C.; Bi, Y.

    1998-06-01

    Two different approaches to hysteresis modeling are compared using a common ground based on energy relations, defined in terms of dissipated and stored energy. Using the Preisach model and assuming that magnetization is mainly due to domain-wall motion, one can derive the expression of magnetization along a major loop typical of the Jiles{endash}Atherton model and then extend its validity to cases where mean-field effects and reversible contributions are present. {copyright} {ital 1998 American Institute of Physics.}

  8. Domain-wall motion in random potential and hysteresis modeling

    NASA Astrophysics Data System (ADS)

    Pasquale, M.; Basso, V.; Bertotti, G.; Jiles, D. C.; Bi, Y.

    1998-06-01

    Two different approaches to hysteresis modeling are compared using a common ground based on energy relations, defined in terms of dissipated and stored energy. Using the Preisach model and assuming that magnetization is mainly due to domain-wall motion, one can derive the expression of magnetization along a major loop typical of the Jiles-Atherton model and then extend its validity to cases where mean-field effects and reversible contributions are present.

  9. A simulation framework for estimating wall stress distribution of abdominal aortic aneurysm.

    PubMed

    Qin, Jing; Zhang, Jing; Chui, Chee-Kong; Huang, Wei-Min; Yang, Tao; Pang, Wai-Man; Sudhakar, Venkatesh; Chang, Stephen

    2011-01-01

    Abdominal aortic aneurysm (AAA) rupture is believed to occur when the mechanical stress acting on the wall exceeds the strength of the wall tissue. In endovascular aneurysm repair, a stent-graft in a catheter is released at the aneurysm site to form a new blood vessel and protect the weakened AAA wall from the pulsatile pressure and, hence, possible rupture. In this paper, we propose a framework to estimate the wall stress distribution of non-stented/stented AAA based on fluid-structure interaction, which is utilized in a surgical simulation system (IRAS). The 3D geometric model of AAA is reconstructed from computed tomography angiographic (CTA) images. Based on our experiments, a combined logarithm and polynomial strain energy equation is applied to model the elastic properties of arterial wall. The blood flow is modeled as laminar, incompressible, and non-Newtonian flow by applying Navier-Stokes equation. The obtained pressure of blood flow is applied as load on the AAA meshes with and without stent-graft and the wall stress distribution is calculated by fluid-structure interaction (FSI) solver equipped in ANSYS. Experiments demonstrate that our analytical results are consistent with clinical observations. PMID:22254456

  10. Quantification of regional myocardial wall motion by cardiovascular magnetic resonance

    PubMed Central

    Jiang, Kai

    2014-01-01

    Cardiovascular magnetic resonance (CMR) is a versatile tool that also allows comprehensive and accurate measurement of both global and regional myocardial contraction. Quantification of regional wall motion parameters, such as strain, strain rate, twist and torsion, has been shown to be more sensitive to early-stage functional alterations. Since the invention of CMR tagging by magnetization saturation in 1988, several CMR techniques have been developed to enable the measurement of regional myocardial wall motion, including myocardial tissue tagging, phase contrast mapping, displacement encoding with stimulated echoes (DENSE), and strain encoded (SENC) imaging. These techniques have been developed with their own advantages and limitations. In this review, two widely used and closely related CMR techniques, i.e., tissue tagging and DENSE, will be discussed from the perspective of pulse sequence development and image-processing techniques. The clinical and preclinical applications of tissue tagging and DENSE in assessing wall motion mechanics in both normal and diseased hearts, including coronary artery diseases, hypertrophic cardiomyopathy, aortic stenosis, and Duchenne muscular dystrophies, will be discussed. PMID:25392821

  11. Observation of a Flowing Duct in the Abdominal Wall by Using Nanoparticles

    PubMed Central

    Jung, Sharon Jiyoon; Kim, Min-Suk; Lee, Jin-Kyu; Kim, Young-Jae; Soh, Kwang-Sup

    2016-01-01

    The primo vascular system (PVS) is being established as a circulatory system that corresponds to acupuncture meridians. There have been two critical questions in making the PVS accepted as a novel liquid flowing system. The first one was directly to show the flow of liquid in PVS and the second one was to explain why it was not observed in the conventional histological study of animal tissues. Flow in the PVS in the abdominal cavity was previously verified by injecting Alcian blue into a primo node. However, the tracing of the dye to other subsystems of the PVS has not been done. In the current work we injected fluorescent nanoparticles (FNPs) into a primo node and traced them along a primo vessel which was inside a fat tissue in the abdominal wall. Linea alba is a white middle line in the abdominal skin of a mammal and a band of fat tissue is located in parallel to the linea alba in the parietal side of the abdominal wall of a rat. In this fat band a primo vessel runs parallel to the prominent blood vessels in the fat band and is located just inside the parietal peritoneum. About the second question on the reason why the PVS was not in conventional histological study the current work provided the answer. Histological analysis with hematoxyline and eosine, Masson’s trichrome, and Toluidine blue could not discriminate the primo vessel even when we knew the location of the PVS by the trace of the FNPs. This clearly explains why the PVS is hard to observe in conventional histology: it is not a matter of resolution but the contrast. The PVS has very similar structure to the connective tissues that surround the PVS. In the current work we propose a method to find the PVS: Observation of mast cell distribution with toluidine blue staining and the PN has a high density of mast cells, while the lymph node has low density. PMID:26937963

  12. Observation of a Flowing Duct in the Abdominal Wall by Using Nanoparticles.

    PubMed

    Jang, HyunSuk; Yoon, Joohwan; Gil, HyunJi; Jung, Sharon Jiyoon; Kim, Min-Suk; Lee, Jin-Kyu; Kim, Young-Jae; Soh, Kwang-Sup

    2016-01-01

    The primo vascular system (PVS) is being established as a circulatory system that corresponds to acupuncture meridians. There have been two critical questions in making the PVS accepted as a novel liquid flowing system. The first one was directly to show the flow of liquid in PVS and the second one was to explain why it was not observed in the conventional histological study of animal tissues. Flow in the PVS in the abdominal cavity was previously verified by injecting Alcian blue into a primo node. However, the tracing of the dye to other subsystems of the PVS has not been done. In the current work we injected fluorescent nanoparticles (FNPs) into a primo node and traced them along a primo vessel which was inside a fat tissue in the abdominal wall. Linea alba is a white middle line in the abdominal skin of a mammal and a band of fat tissue is located in parallel to the linea alba in the parietal side of the abdominal wall of a rat. In this fat band a primo vessel runs parallel to the prominent blood vessels in the fat band and is located just inside the parietal peritoneum. About the second question on the reason why the PVS was not in conventional histological study the current work provided the answer. Histological analysis with hematoxyline and eosine, Masson's trichrome, and Toluidine blue could not discriminate the primo vessel even when we knew the location of the PVS by the trace of the FNPs. This clearly explains why the PVS is hard to observe in conventional histology: it is not a matter of resolution but the contrast. The PVS has very similar structure to the connective tissues that surround the PVS. In the current work we propose a method to find the PVS: Observation of mast cell distribution with toluidine blue staining and the PN has a high density of mast cells, while the lymph node has low density. PMID:26937963

  13. Large-scale motions in a plane wall jet

    NASA Astrophysics Data System (ADS)

    Gnanamanickam, Ebenezer; Jonathan, Latim; Shibani, Bhatt

    2015-11-01

    The dynamic significance of large-scale motions in turbulent boundary layers have been the focus of several recent studies, primarily focussing on canonical flows - zero pressure gradient boundary layers, flows within pipes and channels. This work presents an investigation into the large-scale motions in a boundary layer that is used as the prototypical flow field for flows with large-scale mixing and reactions, the plane wall jet. An experimental investigation is carried out in a plane wall jet facility designed to operate at friction Reynolds numbers Reτ > 1000 , which allows for the development of a significant logarithmic region. The streamwise turbulent intensity across the boundary layer is decomposed into small-scale (less than one integral length-scale δ) and large-scale components. The small-scale energy has a peak in the near-wall region associated with the near-wall turbulent cycle as in canonical boundary layers. However, eddies of large-scales are the dominating eddies having significantly higher energy, than the small-scales across almost the entire boundary layer even at the low to moderate Reynolds numbers under consideration. The large-scales also appear to amplitude and frequency modulate the smaller scales across the entire boundary layer.

  14. Layer-dependent wall properties of abdominal aortic aneurysms: Experimental study and material characterization.

    PubMed

    Sassani, Sophia G; Kakisis, John; Tsangaris, Sokrates; Sokolis, Dimitrios P

    2015-09-01

    Mechanical testing and in-depth characterization of the abdominal aortic aneurysm wall from fifteen patients undergoing open surgery was performed to establish the layer-dependent tissue properties that are non-available in the literature. Quantitative microscopic evaluation was performed to identify the spatial organization of collagen-fiber network. Among a number of candidate models, the four-fiber family (microstructure-motivated) model, especially that including dispersions of fiber angles about the main directions, was superior to the Fung- and Gasser-type models in the fitting quality allowed, though it presented a practical difficulty in parameter estimation, so that an analysis was conducted aiding the identification of a more specific diagonal- and circumferential-fiber family model for all three layers. The adventitia was stiffer and stronger than the other layers, owing to its increased collagen content, and its contribution to the response of the intact wall was augmented being under greater residual tension than the media, whereas the intima was under residual compression. All layers were stiffer circumferentially than longitudinally, due to preferential collagen arrangement along that axis. The histologically-guided material characterization of layered wall presented herein is expected to assist clinical decision, by developing reliable criteria to predict the rupture risk of abdominal aortic aneurysms, and optimize endovascular interventions. PMID:26011656

  15. Local Nanomechanical Motion of the Cell Wall of Saccharomyces cerevisiae

    NASA Astrophysics Data System (ADS)

    Pelling, Andrew E.; Sehati, Sadaf; Gralla, Edith B.; Valentine, Joan S.; Gimzewski, James K.

    2004-08-01

    We demonstrate that the cell wall of living Saccharomyces cerevisiae (baker's yeast) exhibits local temperature-dependent nanomechanical motion at characteristic frequencies. The periodic motions in the range of 0.8 to 1.6 kHz with amplitudes of ~3 nm were measured using the cantilever of an atomic force microscope (AFM). Exposure of the cells to a metabolic inhibitor causes the periodic motion to cease. From the strong frequency dependence on temperature, we derive an activation energy of 58 kJ/mol, which is consistent with the cell's metabolism involving molecular motors such as kinesin, dynein, and myosin. The magnitude of the forces observed (~10 nN) suggests concerted nanomechanical activity is operative in the cell.

  16. The influence of mesh topology in the abdominal wall repair process.

    PubMed

    De Maria, Carmelo; Burchielli, Silvia; Salvadori, Claudia; Santoro, Vito; Montemurro, Francesca; Orsi, Gianni; Vozzi, Giovanni

    2016-08-01

    The tissue integration and the formation of adhesions in the repair of abdominal wall defects are principally led to the topology and the mechanical properties of implanted prosthesis. In this study we analyzed the influence of the topology of the meshes for abdominal wall repair, made of polypropylene (PP), evaluating its ability to prevent and to minimize the formation of adhesions, and to promote tissue ingrowth. Two series of in vivo studies were performed. In the first, two types of PP meshes, a lightweight macroporous mesh (LWM) and a heavyweight microporous mesh (HWM) were compared with determine the optimal porosity for tissue integration. In the second, a composite mesh, Clear Mesh Composite (CMC), made of a LWM sewn on a PP planar smooth film, was compared with a PP planar film, to demonstrate how two different topologies of same material are able to induce different tissue integration with the abdominal wall and different adhesion with internal organs. In both studies, the prostheses were implanted in Wistar rats and histological analysis and mechanical characterization of tissue coupled with the implants were performed. LWM showed better host tissue ingrowth in comparison to HWM. CMC prosthesis showed no adhesions to the viscera and no strong foreign body reaction, moreover its elasticity and anisotropy index were more similar to that of natural tissue. These results demonstrated that the surface morphology of PP surgical meshes allowed to modulate their repair ability. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1220-1228, 2016. PMID:26097153

  17. Intensity modulated radiation-therapy for preoperative posterior abdominal wall irradiation of retroperitoneal liposarcomas

    SciTech Connect

    Bossi, Alberto . E-mail: alberto.bossi@uz.kuleuven.ac.be; De Wever, Ivo; Van Limbergen, Erik; Vanstraelen, Bianca

    2007-01-01

    Purpose: Preoperative external-beam radiation therapy (preop RT) in the management of Retroperitoneal Liposarcomas (RPLS) typically involves the delivery of radiation to the entire tumor mass: yet this may not be necessary. The purpose of this study is to evaluate a new strategy of preop RT for RPLS in which the target volume is limited to the contact area between the tumoral mass and the posterior abdominal wall. Methods and Materials: Between June 2000 and Jan 2005, 18 patients with the diagnosis of RPLS have been treated following a pilot protocol of pre-op RT, 50 Gy in 25 fractions of 2 Gy/day. The Clinical Target Volume (CTV) has been limited to the posterior abdominal wall, region at higher risk for local relapse. A Three-Dimensional conformal (3D-CRT) and an Intensity Modulated (IMRT) plan were generated and compared; toxicity was reported following the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events v3.0. Results: All patients completed the planned treatment and the acute toxicity was tolerable: 2 patients experienced Grade 3 and 1 Grade 2 anorexia while 2 patients developed Grade 2 nausea. IMRT allows a better sparing of the ipsilateral and the contralateral kidney. All tumors were successfully resected without major complications. At a median follow-up of 27 months 2 patients developed a local relapse and 1 lung metastasis. Conclusions: Our strategy of preop RT is feasible and well tolerated: the rate of resectability is not compromised by limiting the preop CTV to the posterior abdominal wall and a better critical-structures sparing is obtained with IMRT.

  18. Abdominal Wall Hematoma as a Rare Complication following Percutaneous Coronary Intervention

    PubMed Central

    Moon, In Tae; Sohn, Young Seok; Lee, Ji Young; Park, Hwan Cheol; Choi, Sung Il; Kim, Soon Gil; Oh, Ji Young

    2016-01-01

    Abdominal wall hematoma is a rare but potentially serious vascular complication that may develop after coronary angiographic procedures. In particular, an oblique muscle hematoma caused by an injury of the circumflex iliac artery is very rare, yet can be managed by conservative treatment including hydration and transfusion. However, when active bleeding continues, angiographic embolization or surgery might be needed. In this study, we report an uncommon case of injury to the circumflex iliac artery by an inappropriate introduction of the hydrophilic guidewire during the performance of a percutaneous coronary intervention.

  19. Systemic juvenile xanthogranulomatosis imitating a malignant abdominal wall tumor with lung metastases.

    PubMed

    Matcham, Nicola J; Andronikou, Savvas; Sibson, Keith; Ramani, Pramila; Grier, David

    2007-01-01

    Juvenile xanthogranulomatosis (JXG) is a rare benign condition, which usually presents with characteristic skin lesions and can be diagnosed clinically. However, systemic JXG may involve a wide range of extracutaneous sites and may pose a diagnostic dilemma for the clinician, radiologist, and pathologist. In particular it may simulate malignancy. Here, we report a case of systemic JXG within the abdominal wall musculature and lungs, which imitated a sarcoma with pulmonary metastases on computerized tomography. To the best of our knowledge, this is the first such reported case. In particular, systemic disease presenting without skin lesions is unusual. PMID:17230073

  20. Intramedullary spinal cord ganglioglioma presenting with abnormal abdominal wall movement. Case report.

    PubMed

    Aslanabadi, Saeid; Azhough, Ramin; Motlagh, Parviz Samad; Hadidchi, Shahram; Tabrizi, Ali Dastranj; Zonouzy, Keivan Kashy

    2004-10-15

    The authors present a case of intramedullary ganglioglioma in a 6-year-old girl. Since the age of 4 months the patient had experienced a spontaneous wavy undulating movement of her anterior abdominal wall resembling a severe peristalsis. The movement was continuous even during sleep, and this symptom was named "belly dance." Magnetic resonance images revealed an intramedullary tumor with ill-defined borders, and the lesion was partially resected. The patient made a good recovery, although 4 years postsurgery her scoliosis had progressed. PMID:15633994

  1. Spatially-constrained probability distribution model of incoherent motion (SPIM) for abdominal diffusion-weighted MRI.

    PubMed

    Kurugol, Sila; Freiman, Moti; Afacan, Onur; Perez-Rossello, Jeannette M; Callahan, Michael J; Warfield, Simon K

    2016-08-01

    Quantitative diffusion-weighted MR imaging (DW-MRI) of the body enables characterization of the tissue microenvironment by measuring variations in the mobility of water molecules. The diffusion signal decay model parameters are increasingly used to evaluate various diseases of abdominal organs such as the liver and spleen. However, previous signal decay models (i.e., mono-exponential, bi-exponential intra-voxel incoherent motion (IVIM) and stretched exponential models) only provide insight into the average of the distribution of the signal decay rather than explicitly describe the entire range of diffusion scales. In this work, we propose a probability distribution model of incoherent motion that uses a mixture of Gamma distributions to fully characterize the multi-scale nature of diffusion within a voxel. Further, we improve the robustness of the distribution parameter estimates by integrating spatial homogeneity prior into the probability distribution model of incoherent motion (SPIM) and by using the fusion bootstrap solver (FBM) to estimate the model parameters. We evaluated the improvement in quantitative DW-MRI analysis achieved with the SPIM model in terms of accuracy, precision and reproducibility of parameter estimation in both simulated data and in 68 abdominal in-vivo DW-MRIs. Our results show that the SPIM model not only substantially reduced parameter estimation errors by up to 26%; it also significantly improved the robustness of the parameter estimates (paired Student's t-test, p < 0.0001) by reducing the coefficient of variation (CV) of estimated parameters compared to those produced by previous models. In addition, the SPIM model improves the parameter estimates reproducibility for both intra- (up to 47%) and inter-session (up to 30%) estimates compared to those generated by previous models. Thus, the SPIM model has the potential to improve accuracy, precision and robustness of quantitative abdominal DW-MRI analysis for clinical applications. PMID

  2. A simple, effective and clinically applicable method to compute abdominal aortic aneurysm wall stress.

    PubMed

    Joldes, Grand Roman; Miller, Karol; Wittek, Adam; Doyle, Barry

    2016-05-01

    Abdominal aortic aneurysm (AAA) is a permanent and irreversible dilation of the lower region of the aorta. It is a symptomless condition that if left untreated can expand to the point of rupture. Mechanically-speaking, rupture of an artery occurs when the local wall stress exceeds the local wall strength. It is therefore desirable to be able to non-invasively estimate the AAA wall stress for a given patient, quickly and reliably. In this paper we present an entirely new approach to computing the wall tension (i.e. the stress resultant equal to the integral of the stresses tangent to the wall over the wall thickness) within an AAA that relies on trivial linear elastic finite element computations, which can be performed instantaneously in the clinical environment on the simplest computing hardware. As an input to our calculations we only use information readily available in the clinic: the shape of the aneurysm in-vivo, as seen on a computed tomography (CT) scan, and blood pressure. We demonstrate that tension fields computed with the proposed approach agree well with those obtained using very sophisticated, state-of-the-art non-linear inverse procedures. Using magnetic resonance (MR) images of the same patient, we can approximately measure the local wall thickness and calculate the local wall stress. What is truly exciting about this simple approach is that one does not need any information on material parameters; this supports the development and use of patient-specific modelling (PSM), where uncertainty in material data is recognised as a key limitation. The methods demonstrated in this paper are applicable to other areas of biomechanics where the loads and loaded geometry of the system are known. PMID:26282385

  3. Comparison of Liver Tumor Motion With and Without Abdominal Compression Using Cine-Magnetic Resonance Imaging

    SciTech Connect

    Eccles, Cynthia L.; Patel, Ritesh; Simeonov, Anna K.; Lockwood, Gina; Haider, Masoom; Dawson, Laura A.

    2011-02-01

    Purpose: Abdominal compression (AC) can be used to reduce respiratory liver motion in patients undergoing liver stereotactic body radiotherapy. The purpose of the present study was to measure the changes in three-dimensional liver tumor motion with and without compression using cine-magnetic resonance imaging. Patients and Methods: A total of 60 patients treated as a part of an institutional research ethics board-approved liver stereotactic body radiotherapy protocol underwent cine T2-weighted magnetic resonance imaging through the tumor centroid in the coronal and sagittal planes. A total of 240 cine-magnetic resonance imaging sequences acquired at one to three images each second for 30-60 s were evaluated using an in-house-developed template matching tool (based on the coefficient correlation) to measure the magnitude of the tumor motion. The average tumor edge displacements were used to determine the magnitude of changes in the caudal-cranial (CC) and anteroposterior (AP) directions, with and without AC. Results: The mean tumor motion without AC of 11.7 mm (range, 4.8-23.3) in the CC direction was reduced to 9.4 mm (range, 1.6-23.4) with AC. The tumor motion was reduced in both directions (CC and AP) in 52% of the patients and in a single direction (CC or AP) in 90% of the patients. The mean decrease in tumor motion with AC was 2.3 and 0.6 mm in the CC and AP direction, respectively. Increased motion occurred in one or more directions in 28% of patients. Clinically significant (>3 mm) decreases were observed in 40% and increases in <2% of patients in the CC direction. Conclusion: AC can significantly reduce three-dimensional liver tumor motion in most patients, although the magnitude of the reduction was smaller than previously reported.

  4. An Abdominal Wall Desmoid Tumour Mimicking Cesarean Scar Endometriomas: A Case Report and Review of the Literature

    PubMed Central

    Vural, Fisun; Müezzinoglu, Bahar

    2015-01-01

    Abdominal wall desmoid tumours (DT) are rare, slow-growing benign muscular-aponeurotic fibrous tumours with the tendency to locally invade and recur. They constitute 0.03% of all neoplasms and high infiltration and recurrence rate, but there is no metastatic potential. Although surgery is the primary treatment modality, the optimal treatment remains unclear. Abdominal wall endometriosis is also an unusual disease, and preoperative clinical diagnosis is not always easy. The preoperative radiologic imaging modalities may not aid all the time. Herein, we report an abdominal mass presenting as cyclic pain. Forty-two years old woman who gave birth by cesarean section admitted the complaints of painful abdominal mass (78x45 mm in size) under her cesarean incision scar. She had severe pain, particularly during menstruation. The clinical and radiological imaging findings mimicking endometrioma. We performed wide surgical excision of mass with a 1 cm tumor-free margin with the diagnosis of a benign mesenchymal tumor in the frozen section. The postoperative course was uneventful and recovered without any complication and recurrence three years after surgery. This report presents a case of abdominal wall desmoid tumor mimicking endometrioma. In this paper, shortcomings in diagnosis, abdominal wall endometriomas, and DTs were discussed in the view of literature. PMID:26500967

  5. Laparoscopic Treatment of Ventral Abdominal Wall Hernias: Preliminary Results in 100 Patients

    PubMed Central

    Martín del Olmo, Juan Carlos; Blanco, Jose Ignacio; de la Cuesta, Carmen; Martín, Fernando; Toledano, Miguel; Perna, Christiam; Vaquero, Carlos

    2000-01-01

    Objective: The laparoscopic treatment of eventrations and ventral hernias has been little used, although these hernias are well suited to a laparoscopic approach. The objective of this study was to investigate the usefulness of a laparoscopic approach in the surgical treatment of ventral hernias. Methods: Between January 1994 and July 1998, a series of 100 patients suffering from major abdominal wall defects were operated on by means of laparoscopic techniques, with a mean postoperative follow-up of 30 months. The mean number of defects was 2.7 per patient, the wall defect was 93 cm2 on average. There were 10 minor hernias (<5 cm), 52 medium-size hernias (5-10 cm), and 38 large hernia (>10 cm). The origin of the wall defect was primary in 21 cases and postsurgical in 79. Three access ports were used, and the defects were covered with PTFE Dual Mesh measuring 19 × 15 cm in 54 cases, 10 x 15 cm in 36 cases, and 12 × 8 cm in 10 cases. An additional mesh had to be added in 21 cases. In the last 30 cases, PTFE Dual Mesh Plus with holes was employed. Results: Average surgery time was 62 minutes. One procedure was converted to open surgery, and only one patient required a second operation in the early postoperative period. Minor complications included 2 patients with abdominal wall edema, 10 seromas, and 3 subcutaneous hematomas. There were no trocar site infections. Two patients developed hernia relapse (2%) in the first month after surgery and were reoperated with a similar laparoscopic technique. Oral intake and mobilization began a few hours after surgery. The mean stay in hospital was 28 hours. Conclusions: Laparoscopic technique makes it possible to avoid large incisions, the placement of drains, and produces a lower number of seromas, infections and relapses. Laparoscopic access considerably shortens the time spent in the hospital. PMID:10917121

  6. Intramuscular abdominal wall endometriosis treated by ultrasound-guided ethanol injection.

    PubMed

    Bozkurt, Murat; Çil, A Said; Bozkurt, Duygu Kara

    2014-12-01

    Abdominal wall endometriosis (AWE) is a rare condition that usually develops in a surgical scar resulting from a Caesarean section. While commonly seen in the cutaneous and subcutaneous fat tissue at the Caesarean scar level, its intramuscular localization is quite rare. Its treatment options consist of the excision of the lesion and/or hormonal therapies, although wide surgical excision is the treatment of choice in the literature. Wide surgical excision may create a defect in the abdominal wall and may increase the risk of hernia formation and mesh complications. This case report describes the clinical and radiological findings and treatment modalities of endometriosis that have appeared in the rectus abdominis muscle of a 25-year-old patient at the Caesarean scar level. Sclerotherapy may be used for endometrioma. We present a new and alternative treatment method using ultrasound-guided intralesional ethanol injection for AWE. Compared with the complications of surgical excision, the complications of sclerotherapy by ethanol are at a more acceptable level. Sclerotherapy by ethanol injection may be an alternative treatment to surgery for AWE. PMID:24667221

  7. Intramuscular Abdominal Wall Endometriosis Treated by Ultrasound-Guided Ethanol Injection

    PubMed Central

    Bozkurt, Murat; Çil, A. Said; Bozkurt, Duygu Kara

    2014-01-01

    Abdominal wall endometriosis (AWE) is a rare condition that usually develops in a surgical scar resulting from a Caesarean section. While commonly seen in the cutaneous and subcutaneous fat tissue at the Caesarean scar level, its intramuscular localization is quite rare. Its treatment options consist of the excision of the lesion and/or hormonal therapies, although wide surgical excision is the treatment of choice in the literature. Wide surgical excision may create a defect in the abdominal wall and may increase the risk of hernia formation and mesh complications. This case report describes the clinical and radiological findings and treatment modalities of endometriosis that have appeared in the rectus abdominis muscle of a 25-year-old patient at the Caesarean scar level. Sclerotherapy may be used for endometrioma. We present a new and alternative treatment method using ultrasound-guided intralesional ethanol injection for AWE. Compared with the complications of surgical excision, the complications of sclerotherapy by ethanol are at a more acceptable level. Sclerotherapy by ethanol injection may be an alternative treatment to surgery for AWE. PMID:24667221

  8. Efficacy and safety of hyaluronate membrane in the rabbit cecum-abdominal wall adhesion model

    PubMed Central

    Kim, Jae Young; Cho, Wan Jin; Kim, Jun Ho; Lim, Sae Hwan; Kim, Hyun Jung; Lee, Young Woo

    2013-01-01

    Purpose Tissue adhesion is a well-known postsurgical phenomenon, causing pain, functional obstruction, and difficult reoperative surgery. To overcome these problems, various synthetic and natural polymer membranes have been developed as postoperative tissue adhesion barriers. However, limitation in their use has hindered its actual application. We prepared a hyaluronate membrane (HM) to evaluate its efficacy and safety as an adhesion barrier compared to a commercialized product (Interceed, Ethicon). Methods To evaluate the antiadhesion effect, a cecum-abdominal wall abrasion model was adopted in a rabbit. The denuded cecum was covered by Interceed or HM or neither and apposed to the abdominal wall (each, n = 10). Four weeks after surgery, the level of adhesion was graded. Acute and chronic toxicity of the three groups were also evaluated. Results Blood samples drawn to evaluate acute toxicity at postoperative day 3 and 7 showed no significant difference among the three groups. The grade and area of adhesion were significantly lower in the HM compared to those of the control and Interceed at four weeks after surgery. Histologic evaluations, which was carried out to estimate tissue reactions at the site of application, as well as to assess chronic toxicity for the major organs, were not significantly different in the three groups. Conclusion This study showed that the antiadhesion efficacy of HM was superior to commercialized antiadhesion membrane, Interceed. Low inflammatory response and nontoxicity were also demonstrated. From these results, we suggest that the HM is a good candidate as a tissue adhesion barrier. PMID:23908960

  9. Whole Abdominal Wall Segmentation using Augmented Active Shape Models (AASM) with Multi-Atlas Label Fusion and Level Set

    PubMed Central

    Xu, Zhoubing; Baucom, Rebeccah B.; Abramson, Richard G.; Poulose, Benjamin K.; Landman, Bennett A.

    2016-01-01

    The abdominal wall is an important structure differentiating subcutaneous and visceral compartments and intimately involved with maintaining abdominal structure. Segmentation of the whole abdominal wall on routinely acquired computed tomography (CT) scans remains challenging due to variations and complexities of the wall and surrounding tissues. In this study, we propose a slice-wise augmented active shape model (AASM) approach to robustly segment both the outer and inner surfaces of the abdominal wall. Multi-atlas label fusion (MALF) and level set (LS) techniques are integrated into the traditional ASM framework. The AASM approach globally optimizes the landmark updates in the presence of complicated underlying local anatomical contexts. The proposed approach was validated on 184 axial slices of 20 CT scans. The Hausdorff distance against the manual segmentation was significantly reduced using proposed approach compared to that using ASM, MALF, and LS individually. Our segmentation of the whole abdominal wall enables the subcutaneous and visceral fat measurement, with high correlation to the measurement derived from manual segmentation. This study presents the first generic algorithm that combines ASM, MALF, and LS, and demonstrates practical application for automatically capturing visceral and subcutaneous fat volumes. PMID:27127333

  10. The muscles of the infrapubic abdominal wall of a 6-month-old Crocodylus niloticus (Reptilia: Crocodylia).

    PubMed

    Fechner, R; Schwarz-Wings, D

    2013-06-01

    The muscles of the infrapubic abdominal wall of crocodilians play an important role in their ventilatory mechanism. Yet the anatomy and homology of these muscles is poorly understood. To gain new insights into the anatomy of the crocodilian infrapubic abdominal wall, we dissected a specimen of Crocodylus niloticus. Origin and insertion of the muscles, as well as their arrangement relative to each other was examined in great detail. The findings were compared with those of other crocodilian taxa to detect potential variability of the muscles of interest. The homology of the muscles was studied by comparing the muscles of the crocodilian infrapubic abdominal wall with those of other diapsids. In Crocodylus niloticus, the infrapubic abdominal wall consists of four muscles: Musculus truncocaudalis, M. ischiotruncus, and Mm. rectus abdominis externus and internus. The arrangement of the muscles of the infrapubic abdominal wall of Crocodylus niloticus is consistent with that found in most other crocodilian taxa. In some crocodilian taxa, an additional muscle, M. ischiopubis, is found. In the remaining diapsids, only M. rectus abdominis is present. The crocodilian M. truncocaudalis, M. ischiotruncus and, if present, M. ischiopubis appear to be derivates of M. rectus abdominis; the development of those might be related to the evolution of the unique crocodilian ventilatory mechanism. PMID:22909340

  11. Comparison of novel synthetic materials with traditional methods to repair exposed abdominal wall fascial defects.

    PubMed

    Aliabadi-Wahle, S; Cnota, M; Choe, E; Jacob, J T; Flint, L M; Ferrara, J J

    1998-01-01

    Repair of large abdominal wall defects is a challenge, particularly when full-thickness tissue loss prohibits coverage of the fascial repair. Two novel synthetic materials (TMS-1 and TMS-2) have been shown to be better accepted than expanded polytetrafluoroethylene (Gore-Tex), and polypropylene (Marlex) in the closure of clean and contaminated fascial wounds that are immediately covered by skin/soft tissue. Therefore, 1-cm2 abdominal wall defects were created in each of the four quadrants of rat groups. Gore-Tex, Marlex, and TMS-1 or TMS-2 were used to repair three defects, the fourth being primarily closed. To ensure that each repair remained exposed, skin edges were sutured to underlying muscle. Additional animal groups underwent the same protocol; however, peritonitis was induced at surgery using a fecal inoculum technique. Animals were sacrificed 2 weeks later, at which time a blinded observer assessed the surface area and severity of adhesions. In clean wounds, the surface area of formed adhesions was less (p < .004) after primary closure than each synthetic material; among the synthetics, TMS-2 caused significantly (p < .01) less extensive adhesions than Marlex. In addition, the severity of adhesions to TMS-2 was comparable to that of defects closed primarily, and less severe (p < .02) than those formed to Gore-Tex and Marlex. In animals with peritonitis, primary closure caused less extensive (p < .03) adhesions than Marlex and Gore-Tex and significantly (p < .002) less severe adhesions than Marlex, Gore-Tex, and TMS-2. However, the severity of adhesions formed to TMS-1 repairs proved comparable to primarily closed wounds. These experiments reaffirm the tenet that, whenever possible, abdominal wounds should undergo primary fascial closure. When soft tissue coverage over the repair cannot be achieved, TMS-2 is well tolerated in clean wounds. However, the superiority of TMS-1 over the other synthetic materials in contaminated wounds suggests it may also

  12. Abdominal wall competence after free transverse rectus abdominis musculocutaneous flap harvest: a prospective study.

    PubMed

    Suominen, S; Asko-Seljavaara, S; Kinnunen, J; Sainio, P; Alaranta, H

    1997-09-01

    A prospective study was designed to evaluate the possible changes in abdominal wall strength following free transverse rectus abdominis musculocutaneous (TRAM) flap surgery for breast reconstruction. Twenty-two patients were examined 1 day before surgery, and at 3, 6, and 12 months postoperatively. Trunk muscle strength was measured by the same physiotherapist using an isokinetic dynamometer (Lido Multi Joint II, Loredan Biomedical Inc., Davies, CA). The peak torque and average torque for both flexion and extension at 60 degrees per second angular velocity were recorded from the curves obtained. There was a significant reduction in trunk flexion strength at 3 months postoperatively (peak torque mean, 92% of the preoperative value; p = 0.04), but this was corrected by 6 months (mean, 96%), and improved to 98% by 12 months. The patient's ability to do curled trunk sit-ups was evaluated by the same physiotherapist and graded on a scale from 1 to 6. In 9 of 19 patients the operation had no effect on sit-up performance during follow-up. In 10 of 19 patients there was a reduction of one or two grades at 3 months that did not improve by 12 months. Magnetic resonance imaging of the abdominal wall was performed on 9 patients. The mean area of the upper third of both rectus muscles was measured on the axial images. At 3 months postoperatively the mean area of the upper third of the donor muscle was significantly larger than the contralateral (p = 0.03). There was no difference in size at 6 months, and by 12 months the donor side was smaller. This prospective study shows that harvesting of a free TRAM flap can cause a subclinical reduction in abdominal strength, although this was not noticed by the patients themselves. PMID:9326701

  13. Image-driven, model-based 3D abdominal motion estimation for MR-guided radiotherapy

    NASA Astrophysics Data System (ADS)

    Stemkens, Bjorn; Tijssen, Rob H. N.; de Senneville, Baudouin Denis; Lagendijk, Jan J. W.; van den Berg, Cornelis A. T.

    2016-07-01

    Respiratory motion introduces substantial uncertainties in abdominal radiotherapy for which traditionally large margins are used. The MR-Linac will open up the opportunity to acquire high resolution MR images just prior to radiation and during treatment. However, volumetric MRI time series are not able to characterize 3D tumor and organ-at-risk motion with sufficient temporal resolution. In this study we propose a method to estimate 3D deformation vector fields (DVFs) with high spatial and temporal resolution based on fast 2D imaging and a subject-specific motion model based on respiratory correlated MRI. In a pre-beam phase, a retrospectively sorted 4D-MRI is acquired, from which the motion is parameterized using a principal component analysis. This motion model is used in combination with fast 2D cine-MR images, which are acquired during radiation, to generate full field-of-view 3D DVFs with a temporal resolution of 476 ms. The geometrical accuracies of the input data (4D-MRI and 2D multi-slice acquisitions) and the fitting procedure were determined using an MR-compatible motion phantom and found to be 1.0–1.5 mm on average. The framework was tested on seven healthy volunteers for both the pancreas and the kidney. The calculated motion was independently validated using one of the 2D slices, with an average error of 1.45 mm. The calculated 3D DVFs can be used retrospectively for treatment simulations, plan evaluations, or to determine the accumulated dose for both the tumor and organs-at-risk on a subject-specific basis in MR-guided radiotherapy.

  14. Abdominal and pancreatic motion correlation using 4D CT, 4D transponders, and a gating belt.

    PubMed

    Betancourt, Ricardo; Zou, Wei; Plastaras, John P; Metz, James M; Teo, Boon-Keng; Kassaee, Alireza

    2013-01-01

    The correlation between the pancreatic and external abdominal motion due to respiration was investigated on two patients. These studies utilized four dimensional computer tomography (4D CT), a four dimensional (4D) electromagnetic transponder system, and a gating belt system. One 4D CT study was performed during simulation to quantify the pancreatic motion using computer tomography images at eight breathing phases. The motion under free breathing and breath-hold were analyzed for the 4D electromagnetic transponder system and the gating belt system during treatment. A linear curve was fitted for all data sets and correlation factors were evaluated between the 4D electromagnetic transponder system and the gating belt system data. The 4D CT study demonstrated a modest correlation between the external marker and the pancreatic motion with R-square values larger than 0.8 for the inferior-superior (inf-sup). Then, the relative pressure from the belt gating system correlated well with the 4D electromagnetic transponder system's motion in the anterior-posterior (ant-post) and the inf-post directions. These directions have a correlation value of -0.93 and 0.76, while the lateral only had a 0.03 correlation coefficient. Based on our limited study, external surrogates can be used as predictors of the pancreatic motion in the inf-sup and the ant-post directions. Although there is a low correlation on the lateral direction, its motion is significantly shorter. In conclusion, an appropriate treatment delivery can be used for pancreatic cancer when an internal tracking system, such as the 4D electromagnetic transponder system, is unavailable. PMID:23652242

  15. Image-driven, model-based 3D abdominal motion estimation for MR-guided radiotherapy.

    PubMed

    Stemkens, Bjorn; Tijssen, Rob H N; de Senneville, Baudouin Denis; Lagendijk, Jan J W; van den Berg, Cornelis A T

    2016-07-21

    Respiratory motion introduces substantial uncertainties in abdominal radiotherapy for which traditionally large margins are used. The MR-Linac will open up the opportunity to acquire high resolution MR images just prior to radiation and during treatment. However, volumetric MRI time series are not able to characterize 3D tumor and organ-at-risk motion with sufficient temporal resolution. In this study we propose a method to estimate 3D deformation vector fields (DVFs) with high spatial and temporal resolution based on fast 2D imaging and a subject-specific motion model based on respiratory correlated MRI. In a pre-beam phase, a retrospectively sorted 4D-MRI is acquired, from which the motion is parameterized using a principal component analysis. This motion model is used in combination with fast 2D cine-MR images, which are acquired during radiation, to generate full field-of-view 3D DVFs with a temporal resolution of 476 ms. The geometrical accuracies of the input data (4D-MRI and 2D multi-slice acquisitions) and the fitting procedure were determined using an MR-compatible motion phantom and found to be 1.0-1.5 mm on average. The framework was tested on seven healthy volunteers for both the pancreas and the kidney. The calculated motion was independently validated using one of the 2D slices, with an average error of 1.45 mm. The calculated 3D DVFs can be used retrospectively for treatment simulations, plan evaluations, or to determine the accumulated dose for both the tumor and organs-at-risk on a subject-specific basis in MR-guided radiotherapy. PMID:27362636

  16. Chest wall motion in preterm infants using respiratory inductive plethysmography.

    PubMed

    Warren, R H; Horan, S M; Robertson, P K

    1997-10-01

    Preterm infant tidal breathing may be different from that of healthy full-term infants because of various features of the premature thorax. The purpose of this project was to describe chest wall motion in the preterm infant (gestational age <37 weeks) and compare it with chest wall motion data in a group of healthy, full-term infants. We wanted to use an objective bedside method for assessment with minimal disruption to the infant. The study population consisted of 61 preterm human infants whose mean(+/-sD) postconceptional age at time of study was 35.3+/-2.1 weeks. During the study, the infants were quietly awake in a prone position. Preterm infants had initially been admitted to a level III neonatal intensive care unit for acute management and had been transferred to a step-down area, where they were in stable condition for study. Data were collected with a semiquantitatively calibrated, noninvasive respiratory inductive plethysmograph. Mean(+/-SD) phase angle was significantly greater in preterm infants than in full-term infants (60.6+/-39.8 degrees versus 12.5+/-5.0 degrees, respectively, p < or = 0.0001). The laboured breathing index was significantly greater in preterm infants than in full-term infants (1.35+/-0.35 versus 1.01+/-0.01, respectively, p = 0.001). The ribcage contribution to breathing did not differ significantly between preterm and full-term infants (25.5+/-17.7% versus 36.3+/-14.4%, respectively, p = 0.11). These results indicate a significant increase in the degree of ribcage and abdomen asynchrony in the preterm subjects compared to the full-term infants. Plethysmography provided a time-efficient and objective method of assessing chest wall motion in this fragile population. PMID:9387956

  17. Sustained chiral magnetic domain wall motion driven by spin-orbit torques under the tilted current

    NASA Astrophysics Data System (ADS)

    He, Peng-Bin; Yan, Han; Cai, Meng-Qiu; Li, Zai-Dong

    2016-06-01

    We theoretically investigate the steady magnetic domain wall driven by spin-orbit torques in the heavy-metal/magnet bilayers with perpendicular anisotropy. Based on collective coordinates method and stability analysis, we analyze the effects of tilted current and Dzyaloshinskii-Moriya interaction on the wall. We find that the wall acquires a sustained motion in the high-current regime by deviating the current from the wall track. Also, a persistent motion can be supported by the competition between spin-orbit torques and Dzyaloshinskii-Moriya interaction in transforming wall type. In the low-current regime, there exist a switching of wall chirality and a reversal of wall motion.

  18. Rashba Torque Driven Domain Wall Motion in Magnetic Helices

    NASA Astrophysics Data System (ADS)

    Pylypovskyi, Oleksandr V.; Sheka, Denis D.; Kravchuk, Volodymyr P.; Yershov, Kostiantyn V.; Makarov, Denys; Gaididei, Yuri

    2016-03-01

    Manipulation of the domain wall propagation in magnetic wires is a key practical task for a number of devices including racetrack memory and magnetic logic. Recently, curvilinear effects emerged as an efficient mean to impact substantially the statics and dynamics of magnetic textures. Here, we demonstrate that the curvilinear form of the exchange interaction of a magnetic helix results in an effective anisotropy term and Dzyaloshinskii–Moriya interaction with a complete set of Lifshitz invariants for a one-dimensional system. In contrast to their planar counterparts, the geometrically induced modifications of the static magnetic texture of the domain walls in magnetic helices offer unconventional means to control the wall dynamics relying on spin-orbit Rashba torque. The chiral symmetry breaking due to the Dzyaloshinskii–Moriya interaction leads to the opposite directions of the domain wall motion in left- or right-handed helices. Furthermore, for the magnetic helices, the emergent effective anisotropy term and Dzyaloshinskii–Moriya interaction can be attributed to the clear geometrical parameters like curvature and torsion offering intuitive understanding of the complex curvilinear effects in magnetism.

  19. Rashba Torque Driven Domain Wall Motion in Magnetic Helices.

    PubMed

    Pylypovskyi, Oleksandr V; Sheka, Denis D; Kravchuk, Volodymyr P; Yershov, Kostiantyn V; Makarov, Denys; Gaididei, Yuri

    2016-01-01

    Manipulation of the domain wall propagation in magnetic wires is a key practical task for a number of devices including racetrack memory and magnetic logic. Recently, curvilinear effects emerged as an efficient mean to impact substantially the statics and dynamics of magnetic textures. Here, we demonstrate that the curvilinear form of the exchange interaction of a magnetic helix results in an effective anisotropy term and Dzyaloshinskii-Moriya interaction with a complete set of Lifshitz invariants for a one-dimensional system. In contrast to their planar counterparts, the geometrically induced modifications of the static magnetic texture of the domain walls in magnetic helices offer unconventional means to control the wall dynamics relying on spin-orbit Rashba torque. The chiral symmetry breaking due to the Dzyaloshinskii-Moriya interaction leads to the opposite directions of the domain wall motion in left- or right-handed helices. Furthermore, for the magnetic helices, the emergent effective anisotropy term and Dzyaloshinskii-Moriya interaction can be attributed to the clear geometrical parameters like curvature and torsion offering intuitive understanding of the complex curvilinear effects in magnetism. PMID:27008975

  20. Rashba Torque Driven Domain Wall Motion in Magnetic Helices

    PubMed Central

    Pylypovskyi, Oleksandr V.; Sheka, Denis D.; Kravchuk, Volodymyr P.; Yershov, Kostiantyn V.; Makarov, Denys; Gaididei, Yuri

    2016-01-01

    Manipulation of the domain wall propagation in magnetic wires is a key practical task for a number of devices including racetrack memory and magnetic logic. Recently, curvilinear effects emerged as an efficient mean to impact substantially the statics and dynamics of magnetic textures. Here, we demonstrate that the curvilinear form of the exchange interaction of a magnetic helix results in an effective anisotropy term and Dzyaloshinskii–Moriya interaction with a complete set of Lifshitz invariants for a one-dimensional system. In contrast to their planar counterparts, the geometrically induced modifications of the static magnetic texture of the domain walls in magnetic helices offer unconventional means to control the wall dynamics relying on spin-orbit Rashba torque. The chiral symmetry breaking due to the Dzyaloshinskii–Moriya interaction leads to the opposite directions of the domain wall motion in left- or right-handed helices. Furthermore, for the magnetic helices, the emergent effective anisotropy term and Dzyaloshinskii–Moriya interaction can be attributed to the clear geometrical parameters like curvature and torsion offering intuitive understanding of the complex curvilinear effects in magnetism. PMID:27008975

  1. Domain wall motion in magnetic nanowires: an asymptotic approach.

    PubMed

    Goussev, Arseni; Lund, Ross G; Robbins, J M; Slastikov, Valeriy; Sonnenberg, Charles

    2013-12-01

    We develop a systematic asymptotic description for domain wall motion in one-dimensional magnetic nanowires under the influence of small applied magnetic fields and currents and small material anisotropy. The magnetization dynamics, as governed by the Landau-Lifshitz-Gilbert equation, is investigated via a perturbation expansion. We compute leading-order behaviour, propagation velocities and first-order corrections of both travelling waves and oscillatory solutions, and find bifurcations between these two types of solutions. This treatment provides a sound mathematical foundation for numerous results in the literature obtained through more ad hoc arguments. PMID:24353468

  2. Domain wall motion in magnetic nanowires: an asymptotic approach

    PubMed Central

    Goussev, Arseni; Lund, Ross G.; Robbins, J. M.; Slastikov, Valeriy; Sonnenberg, Charles

    2013-01-01

    We develop a systematic asymptotic description for domain wall motion in one-dimensional magnetic nanowires under the influence of small applied magnetic fields and currents and small material anisotropy. The magnetization dynamics, as governed by the Landau–Lifshitz–Gilbert equation, is investigated via a perturbation expansion. We compute leading-order behaviour, propagation velocities and first-order corrections of both travelling waves and oscillatory solutions, and find bifurcations between these two types of solutions. This treatment provides a sound mathematical foundation for numerous results in the literature obtained through more ad hoc arguments. PMID:24353468

  3. Metachronous carcinoma of rectum with reconstruction of a full-thickness abdominal wall defect using a pedicled anterolateral thigh flap

    PubMed Central

    Kok, Amy Siu Yan

    2016-01-01

    Reconstruction of large, complex defects of the abdominal wall after resection of malignant tumors can be challenging. The transfer of an anterolateral thigh (ALT) flap is a feasible and effective option. However, no report has been published on the use of ALT flap after metachronous colonic tumor resection so far. We present an original case of resection of metachronous carcinoma of rectum with reconstruction of the abdominal wall defect using an ALT flap harvested with its aponeurosis. The postoperative course was uncomplicated. Functional and esthetic results were satisfactory. There was no postoperative incisional hernia or tumor recurrence. We conclude that abdominal wall defects of large sizes can be successfully reconstructed using an appropriately designed ALT flap; a simple, single-stage effective reconstruction. PMID:27161142

  4. Abdominal Wall Metastasis of Uterine Papillary Serous Carcinoma in a Post-Menopausal Woman: A Case Report

    PubMed Central

    Park, Jung-Woo

    2014-01-01

    Uterine papillary serous carcinoma (UPSC) is an aggressive form of endometrial cancer characterized by a high recurrence rate and poor prognosis. We report a case of a 58-year-old post-menopausal woman with an abdominal wall metastasis in stage IA UPSC. After surgical staging, she did not receive additional adjuvant therapy. An egg sized palpable mass developed in the right lower abdomen after 8 months. Both Abdominopelvic computed tomography (CT) and positron emission tomography (PET)-CT revealed a metastatic lesion in the abdominal wall. Hence, surgical excision was performed. The pathological findings showed metastatic UPSC with clear resection margin. After the diagnosis of UPSC metastasis in the abdominal wall, she received chemotherapy utilizing paclitaxel and carboplatin. After 3 years, no evidence of recurrence was found. Therefore, we suggest that even when UPSC is confined to the endometrium without lymph node metastasis and without lymphovascular invasion, chemotherapy should be considered as a postoperative adjuvant therapy. PMID:25371890

  5. Abdominal wall metastasis of uterine papillary serous carcinoma in a post-menopausal woman: a case report.

    PubMed

    Park, Jung-Woo; Hwang, Sung-Ook

    2014-04-01

    Uterine papillary serous carcinoma (UPSC) is an aggressive form of endometrial cancer characterized by a high recurrence rate and poor prognosis. We report a case of a 58-year-old post-menopausal woman with an abdominal wall metastasis in stage IA UPSC. After surgical staging, she did not receive additional adjuvant therapy. An egg sized palpable mass developed in the right lower abdomen after 8 months. Both Abdominopelvic computed tomography (CT) and positron emission tomography (PET)-CT revealed a metastatic lesion in the abdominal wall. Hence, surgical excision was performed. The pathological findings showed metastatic UPSC with clear resection margin. After the diagnosis of UPSC metastasis in the abdominal wall, she received chemotherapy utilizing paclitaxel and carboplatin. After 3 years, no evidence of recurrence was found. Therefore, we suggest that even when UPSC is confined to the endometrium without lymph node metastasis and without lymphovascular invasion, chemotherapy should be considered as a postoperative adjuvant therapy. PMID:25371890

  6. 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

  7. Obesity increases the odds of acquiring and incarcerating noninguinal abdominal wall hernias.

    PubMed

    Lau, Briana; Kim, Hanjoo; Haigh, Philip I; Tejirian, Talar

    2012-10-01

    The current data available describing the relationship of obesity and abdominal wall hernias is sparse. The objective of this study was to investigate the current prevalence of noninguinal abdominal wall hernias and their correlation with body mass index (BMI) and other demographic risk factors. Patients with umbilical, incisional, ventral, epigastric, or Spigelian hernias with or without incarceration were identified using the regional database for 14 hospitals over a 3-year period. Patients were stratified based on their BMI. Univariate and multivariate analyses were performed to distinguish other significant risk factors associated with the hernias. Of 2,807,414 patients, 26,268 (0.9%) had one of the specified diagnoses. Average age of the patients was 52 years and 61 per cent were male. The majority of patients had nonincarcerated umbilical hernias (74%). Average BMI was 32 kg/m2. Compared with patients with a normal BMI, the odds of having a hernia increased with BMI: BMI of 25 to 29.9 kg/m2 odds ratio (OR) 1.63, BMI of 30 to 39.9 kg/m2 OR 2.62, BMI 40 to 49.9 kg/m2 OR 3.91, BMI 50 to 59.9 kg/m2 OR 4.85, and BMI greater than 60 kg/m2 OR 5.17 (P<0.0001). Age older than 50 years was associated with a higher risk for having a hernia (OR, 2.12; 95% [CI], 2.07 to 2.17), whereas female gender was associated with a lower risk (OR, 0.53; 95% CI, 0.52 to 0.55). Those with incarcerated hernias had a higher average BMI (32 kg/m2 vs 35 kg/m2; P<0.0001). Overall, BMI greater than 40 kg/m2 showed an increased chance of incarceration, and a BMI greater than 60 kg/m2 had the highest chance of incarceration, OR 12.7 (P<0.0001). Age older than 50 years and female gender were also associated with a higher risk of incarceration (OR, 1.28; 95% CI, 1.02 to 1.59 and OR, 1.80; CI, 1.45 to 2.24). Increasing BMI and increasing age are associated with a higher prevalence and an increased risk of incarceration of noninguinal abdominal wall hernias. PMID:23025954

  8. Evaluation of porcine dermal collagen (Permacol) used in abdominal wall reconstruction.

    PubMed

    Hsu, Patrick W; Salgado, Christopher J; Kent, Kathryn; Finnegan, Matthew; Pello, Mark; Simons, Robert; Atabek, Umur; Kann, Brian

    2009-11-01

    Various methods have been employed to reconstruct complex abdominal wall defects. Structural prosthetic materials such as polypropylene mesh and ePTFE (expanded polytetrafluoroethylene) have been widely used to close these large fascial defects, however, complications with infection and adhesions have led to the recent use of more biocompatible implants. Permacol (acellular porcine dermis) is used as a dermal scaffold, which eventually becomes vascularised and remodelled to reconstruct the abdominal wall in these complex patients. A retrospective review was performed of all patients who underwent consecutive abdominal wall reconstruction with Permacol at our institution in the year 2006. Twenty-eight patients were identified and included in our study. Factors evaluated were: body mass index, relevant co-morbidities, aetiology of hernia, hernia defect size based on CT scan and intraoperative measurement, size of Permacol implant, length of hospital stay, and postoperative complications. Surgical technique was standardised among six surgeons and involved a single layer of acellular porcine dermis as a subfascial 'underlay' graft under moderate tension upon maximal hernia reduction. Tissue expanders were not required for skin closure. Out of 28 patients, 12 were male and 16 were female. Mean intraoperative hernia size was 150 cm(2) (range of 10 cm(2) to 600 cm(2)). Mean age was 55 years with an average body mass index (BMI) of 34 (largest BMI of 61.4). Defects were attributed to either a previous laparotomy incision or open abdomen. Mean hospital stay was 9.67 days. At a mean follow-up of sixteen months, there were three recurrent hernias (10.7%) based on physical examination and postoperative CT scan evaluation. One patient developed a superficial wound dehiscence which was successfully treated with local wound care and one patient developed a cellulitis which was successfully treated with antibiotic therapy. Four patients (14.3%) developed a chronic, non

  9. Expression of fibrinolytic genes in atherosclerotic abdominal aortic aneurysm wall. A possible mechanism for aneurysm expansion.

    PubMed Central

    Schneiderman, J; Bordin, G M; Engelberg, I; Adar, R; Seiffert, D; Thinnes, T; Bernstein, E F; Dilley, R B; Loskutoff, D J

    1995-01-01

    Expansion of atherosclerotic abdominal aortic aneurysm (AAA) has been attributed to remodeling of the extracellular matrix by active proteolysis. We used in situ hybridization to analyze the expression of fibrinolytic genes in aneurysm wall from eight AAA patients. All specimens exhibited specific areas of inflammatory infiltrates with macrophage-like cells expressing urokinase-type plasminogen activator (u-PA) and tissue-type PA (t-PA) mRNA. Type 1 PA inhibitor (PAI-1) mRNA was expressed at the base of the necrotic atheroma of all specimens and also within some of the inflammatory infiltrates where it frequently colocalized in regions containing u-PA and t-PA mRNA expressing cells. However, in these areas, the cellular distribution of the transcripts for t-PA and u-PA extended far beyond the areas of PAI-1 expression. These observations suggest a local ongoing proteolytic process, one which is only partially counteracted by the more restricted expression of PAI-1 mRNA. An abundance of capillaries was also obvious in all inflammatory infiltrates and may reflect local angiogenesis in response to active pericellular fibrinolysis. The increased fibrinolytic capacity in AAA wall may promote angiogenesis and contribute to local proteolytic degradation of the aortic wall leading to physical weakening and active expansion of the aneurysm. Images PMID:7615837

  10. Unexpected Abscess Localization of the Anterior Abdominal Wall in an ADPKD Patient Undergoing Hemodialysis.

    PubMed

    Sabanis, Nikos; Paschou, Eleni; Gavriilaki, Eleni; Mourounoglou, Maria; Vasileiou, Sotirios

    2015-01-01

    Autosomal Dominant Polycystic Kidney Disease (ADPKD) is one of the most common monogenic disorders and the leading inheritable cause of end-stage renal disease worldwide. Cystic and noncystic extrarenal manifestations are correlated with variable clinical presentations so that an inherited disorder is now considered a systemic disease. Kidney and liver cystic infections are the most common infectious complications in ADPKD patients. Furthermore, it is well known that ADPKD is commonly associated with colonic diverticular disease which recently has been reported to be linked to increased risk of infection on hemodialysis patients. Herein, we present a case of anterior abdominal wall abscess caused by Enterococcus faecalis in a patient with ADPKD undergoing hemodialysis. Although the precise pathway of infection remains uncertain, the previous medical history as well as the clinical course of our patient led us to hypothesize an alternative route of infection from the gastrointestinal tract through an aberrant intestinal barrier into the bloodstream and eventually to an atypical location. PMID:26301109

  11. Spontaneous extraskeletal osteosarcoma with various histological growth patterns in the abdominal wall of an ICR mouse

    PubMed Central

    Ito, Tsuyoshi; Katoh, Yoshitaka; Shimada, Yuko; Ohnuma-Koyama, Aya; Takahashi, Naofumi; Kuwahara, Maki; Harada, Takanori

    2015-01-01

    Extraskeletal osteosarcoma is extremely rare in mice. This case report demonstrates a spontaneous murine extraskeletal osteosarcoma that exhibited various histological growth patterns in an ICR mouse. At necropsy, the tumor mass was located in the abdominal wall and was 45 × 30 × 25 mm in size. Histopathologically, the tumor showed the following four growth patterns: a solid pattern of polygonal cells embedded in an osteoid eosinophilic matrix with calcification, an irregular sheet pattern of short spindle cells accompanying some eosinophilic multinucleated cells, a fascicular pattern of spindle cells and a cystic pattern lined by short spindle cells. Immunohistochemically, most of the tumor cells were positive for vimentin, proliferating cell nuclear antigen and osterix. The multinucleated cells mentioned above were desmin positive and were regarded as regenerative striated muscles but not tumor cells. Since no clear continuity with normal bone tissues was observed, the tumor was diagnosed as an “extraskeletal osteosarcoma.” PMID:26989300

  12. Aesthetic aspects of abdominal wall and external genital reconstructive surgery in bladder exstrophy-epispadias complex.

    PubMed

    VanderBrink, Brian A; Stock, Jeffrey A; Hanna, Moneer K

    2006-03-01

    Long-term follow-up of patients born with classical bladder exstrophy-epispadias complex (EEC) reveals that many of them suffer from poor self-image, and the aesthetic aspects of the genitalia and lower abdomen acquire greater significance with age. In this article, we review the aesthetic outcomes in performing puboplasty, umbilicoplasty, and genitoplasty in patients born with EEC. Retrospective review of the cosmetic and functional outcomes in 116 patients born with EEC treated by puboplasty, umbilicoplasty, or genitoplasty was performed. Satisfaction with the cosmetic and functional outcomes of these three reconstructive surgeries was high following initial reconstructive efforts (> 90%). Attention to cosmesis during abdominal wall and genital reconstruction for EEC helps to improve a patient's perception of body image and self-esteem. Our experience with these procedures over the past 25 years demonstrated that the efforts directed toward aesthetics have been well worthwhile. PMID:16527001

  13. Elasticity mapping of murine abdominal organs in vivo using harmonic motion imaging (HMI)

    NASA Astrophysics Data System (ADS)

    Payen, Thomas; Palermo, Carmine F.; Sastra, Stephen A.; Chen, Hong; Han, Yang; Olive, Kenneth P.; Konofagou, Elisa E.

    2016-08-01

    Recently, ultrasonic imaging of soft tissue mechanics has been increasingly studied to image otherwise undetectable pathologies. However, many underlying mechanisms of tissue stiffening remain unknown, requiring small animal studies and adapted elasticity mapping techniques. Harmonic motion imaging (HMI) assesses tissue viscoelasticity by inducing localized oscillation from a periodic acoustic radiation force. The objective of this study was to evaluate the feasibility of HMI for in vivo elasticity mapping of abdominal organs in small animals. Pathological cases, i.e. chronic pancreatitis and pancreatic cancer, were also studied in vivo to assess the capability of HMI for detection of the change in mechanical properties. A 4.5 MHz focused ultrasound transducer (FUS) generated an amplitude-modulated beam resulting in 50 Hz harmonic tissue oscillations at its focus. Axial tissue displacement was estimated using 1D-cross-correlation of RF signals acquired with a 7.8 MHz diagnostic transducer confocally aligned with the FUS. In vitro results in canine liver and kidney showed the correlation between HMI displacement and Young’s moduli measured by rheometry compression testing. HMI was capable of providing reproducible elasticity maps of the mouse abdominal region in vivo allowing the identification of, from stiffest to softest, the murine kidney, pancreas, liver, and spleen. Finally, pancreata affected by pancreatitis and pancreatic cancer showed HMI displacements 1.7 and 2.2 times lower than in the control case, respectively, indicating higher stiffness. The HMI displacement amplitude was correlated with the extent of fibrosis as well as detecting the very onset of stiffening even before fibrosis could be detected on H&E. This work shows that HMI can produce reliable elasticity maps of mouse abdominal region in vivo, thus providing a potentially critical tool to assess pathologies affecting organ elasticity.

  14. Elasticity mapping of murine abdominal organs in vivo using harmonic motion imaging (HMI).

    PubMed

    Payen, Thomas; Palermo, Carmine F; Sastra, Stephen A; Chen, Hong; Han, Yang; Olive, Kenneth P; Konofagou, Elisa E

    2016-08-01

    Recently, ultrasonic imaging of soft tissue mechanics has been increasingly studied to image otherwise undetectable pathologies. However, many underlying mechanisms of tissue stiffening remain unknown, requiring small animal studies and adapted elasticity mapping techniques. Harmonic motion imaging (HMI) assesses tissue viscoelasticity by inducing localized oscillation from a periodic acoustic radiation force. The objective of this study was to evaluate the feasibility of HMI for in vivo elasticity mapping of abdominal organs in small animals. Pathological cases, i.e. chronic pancreatitis and pancreatic cancer, were also studied in vivo to assess the capability of HMI for detection of the change in mechanical properties. A 4.5 MHz focused ultrasound transducer (FUS) generated an amplitude-modulated beam resulting in 50 Hz harmonic tissue oscillations at its focus. Axial tissue displacement was estimated using 1D-cross-correlation of RF signals acquired with a 7.8 MHz diagnostic transducer confocally aligned with the FUS. In vitro results in canine liver and kidney showed the correlation between HMI displacement and Young's moduli measured by rheometry compression testing. HMI was capable of providing reproducible elasticity maps of the mouse abdominal region in vivo allowing the identification of, from stiffest to softest, the murine kidney, pancreas, liver, and spleen. Finally, pancreata affected by pancreatitis and pancreatic cancer showed HMI displacements 1.7 and 2.2 times lower than in the control case, respectively, indicating higher stiffness. The HMI displacement amplitude was correlated with the extent of fibrosis as well as detecting the very onset of stiffening even before fibrosis could be detected on H&E. This work shows that HMI can produce reliable elasticity maps of mouse abdominal region in vivo, thus providing a potentially critical tool to assess pathologies affecting organ elasticity. PMID:27401609

  15. Patient-specific modelling of abdominal aortic aneurysms: The influence of wall thickness on predicted clinical outcomes.

    PubMed

    Conlisk, Noel; Geers, Arjan J; McBride, Olivia M B; Newby, David E; Hoskins, Peter R

    2016-06-01

    Rupture of abdominal aortic aneurysms (AAAs) is linked to aneurysm morphology. This study investigates the influence of patient-specific (PS) AAA wall thickness on predicted clinical outcomes. Eight patients under surveillance for AAAs were selected from the MA(3)RS clinical trial based on the complete absence of intraluminal thrombus. Two finite element (FE) models per patient were constructed; the first incorporated variable wall thickness from CT (PS_wall), and the second employed a 1.9mm uniform wall (Uni_wall). Mean PS wall thickness across all patients was 1.77±0.42mm. Peak wall stress (PWS) for PS_wall and Uni_wall models was 0.6761±0.3406N/mm(2) and 0.4905±0.0850N/mm(2), respectively. In 4 out of 8 patients the Uni_wall underestimated stress by as much as 55%; in the remaining cases it overestimated stress by up to 40%. Rupture risk more than doubled in 3 out of 8 patients when PS_wall was considered. Wall thickness influenced the location and magnitude of PWS as well as its correlation with curvature. Furthermore, the volume of the AAA under elevated stress increased significantly in AAAs with higher rupture risk indices. This highlights the sensitivity of standard rupture risk markers to the specific wall thickness strategy employed. PMID:27056256

  16. Combined therapy of NPWT and bipedicled flap as an alternative approach for giant abdominal wall defect with significant visceral edema: report of a case

    PubMed Central

    Yasui, Go; Furukawa, Hiroshi; Warabi, Takehiro; Hayashi, Toshihiko; Oyama, Akihiko; Funayama, Emi; Yamamoto, Yuhei

    2015-01-01

    Abstract Open abdomen management is commonly used for the critically injured patients to avoid abdominal compartment syndrome. But it usually continues for days to weeks and finally results in abdominal wall defect that is too wide to close at once. This article presents an alternative approach to close the giant abdominal wall defect by using the combination of bipedicled flaps with the components separation technique and V.A.C.® system.

  17. Effects of arterial blood flow on walls of the abdominal aorta: distributions of wall shear stress and oscillatory shear index determined by phase-contrast magnetic resonance imaging.

    PubMed

    Sughimoto, Koichi; Shimamura, Yoshiaki; Tezuka, Chie; Tsubota, Ken'ichi; Liu, Hao; Okumura, Kenichiro; Masuda, Yoshitada; Haneishi, Hideaki

    2016-07-01

    Although abdominal aortic aneurysms (AAAs) occur mostly inferior to the renal artery, the mechanism of the development of AAA in relation to its specific location is not yet clearly understood. The objective of this study was to evaluate the hypothesis that even healthy volunteers may manifest specific flow characteristics of blood flow and alter wall shear or oscillatory shear stress in the areas where AAAs commonly develop. Eight healthy male volunteers were enrolled in this prospective study, aged from 24 to 27. Phase-contrast magnetic resonance imaging (MRI) was performed with electrocardiographic triggering. Flow-sensitive four-dimensional MR imaging of the abdominal aorta, with three-directional velocity encoding, including simple morphological image acquisition, was performed. Information on specific locations on the aortic wall was applied to the flow encodes to calculate wall shear stress (WSS) and oscillatory shear index (OSI). While time-framed WSS showed the highest peak of 1.14 ± 0.25 Pa in the juxtaposition of the renal artery, the WSS plateaued to 0.61 Pa at the anterior wall of the abdominal aorta. The OSI peaked distal to the renal arteries at the posterior wall of the abdominal aorta of 0.249 ± 0.148, and was constantly elevated in the whole abdominal aorta at more than 0.14. All subjects were found to have elevated OSI in regions where AAAs commonly occur. These findings indicate that areas of constant peaked oscillatory shear stress in the infra-renal aorta may be one of the factors that lead to morphological changes over time, even in healthy individuals. PMID:26481791

  18. [Case of a Plasmacytoid Urothelial Carcinoma Identified Due to the Hardening of the Abdominal Wall].

    PubMed

    Yanagisawa, Masahiro; Kawakami, Toshifumi; Suzuki, Kotaro; Nakayama, Takashi

    2016-02-01

    The patient was a 75 year-old male. Noticing areas of hardening in the lower abdomen, and consequently feelings of systemic fatigue and difficulty in walking, the patient visited a clinic and was diagnosed with kidney failure prior to the visit to our clinic. Computed tomography and magnetic resonance imaging showed thickness of the rectus abdominis muscle and the bladder wall, and bilateral hydronephrosis was also identified. As no explicit tumor was identified in the bladder, the patient underwent biopsies of the abdominal wall and bladder membrane mucous, and was diagnosed with a plasmacytoid urothelial carcinoma primarily developed in the bladder. The patient displayed a poor general state of health and died five months after the diagnosis. It is known that plasmacytoid urothelial carcinomas progress rapidly and the prognosis is poorer than for the micropapillary variant. It is important to obtain a tissue specimen in the early stage of this disease because there are cases in which no explicit tumor can be identified. Furthermore, the value of carbohydrate antigen (CA) 19-9 of the patient was much higher than would be expected as normal at the first visit. It kept rising during the follow-up and was useful as a marker to indicate the progress of the disease. PMID:27018411

  19. Stochastic modelling of wall stresses in abdominal aortic aneurysms treated by a gene therapy.

    PubMed

    Mohand-Kaci, Faïza; Ouni, Anissa Eddhahak; Dai, Jianping; Allaire, Eric; Zidi, Mustapha

    2012-01-01

    A stochastic mechanical model using the membrane theory was used to simulate the in vivo mechanical behaviour of abdominal aortic aneurysms (AAAs) in order to compute the wall stresses after stabilisation by gene therapy. For that, both length and diameter of AAAs rats were measured during their expansion. Four groups of animals, control and treated by an endovascular gene therapy during 3 or 28 days were included. The mechanical problem was solved analytically using the geometric parameters and assuming the shape of aneurysms by a 'parabolic-exponential curve'. When compared to controls, stress variations in the wall of AAAs for treated arteries during 28 days decreased, while they were nearly constant at day 3. The measured geometric parameters of AAAs were then investigated using probability density functions (pdf) attributed to every random variable. Different trials were useful to define a reliable confidence region in which the probability to have a realisation is equal to 99%. The results demonstrated that the error in the estimation of the stresses can be greater than 28% when parameters uncertainties are not considered in the modelling. The relevance of the proposed approach for the study of AAA growth may be studied further and extended to other treatments aimed at stabilisation AAAs, using biotherapies and pharmacological approaches. PMID:21264784

  20. Motion of red blood cells near microvessel walls: effects of a porous wall layer

    PubMed Central

    HARIPRASAD, DANIEL S.; SECOMB, TIMOTHY W.

    2013-01-01

    A two-dimensional model is used to simulate the motion and deformation of a single mammalian red blood cell (RBC) flowing close to the wall of a microvessel, taking into account the effects of a porous endothelial surface layer (ESL) lining the vessel wall. Migration of RBCs away from the wall leads to the formation of a cell-depleted layer near the wall, which has a large effect on the resistance to blood flow in microvessels. The objective is to examine the mechanical factors causing this migration, including the effects of the ESL. The vessel is represented as a straight parallel-sided channel. The RBC is represented as a set of interconnected viscoelastic elements, suspended in plasma, a Newtonian fluid. The ESL is represented as a porous medium, and plasma flow in the layer is computed using the Brinkman approximation. It is shown that an initially circular cell positioned close to the ESL in a shear flow is deformed into an asymmetric shape. This breaking of symmetry leads to migration away from the wall. With increasing hydraulic resistivity of the layer, the rate of lateral migration increases. It is concluded that mechanical interactions of RBCs flowing in microvessels with a porous wall layer may reduce the rate of lateral migration and hence reduce the width of the cell-depleted zone external to the ESL, relative to the cell-depleted zone that would be formed if the interface between the ESL and free-flowing plasma were replaced by an impermeable boundary. PMID:23493820

  1. Wall motion in expiratory flow limitation: choke and flutter.

    PubMed

    Webster, P M; Sawatzky, R P; Hoffstein, V; Leblanc, R; Hinchey, M J; Sullivan, P A

    1985-10-01

    Limitation of expiratory airflow from mammalian airways is currently understood to be due to choking at wave speed (S. V. Dawson and E. A. Elliott. J. Appl. Physiol. 43: 498-515, 1977). A critical weakness of the theory is the lack of a mechanism for the dissipation of energy when effort exceeds that needed for maximal flow. We have observed substantial wall motion with flow limitation in a physical model of a trachea. Therefore we have examined a simple two-dimensional mathematical model, designed to approximate the behavior of the physical model of the trachea, to try to identify a relationship between flow limitation and wall oscillation. The model matches wave-speed predictions when only long waves are considered. The model predicts that aerodynamic flutter will occur in the zone of supercritical flow described in wave-speed theory. Aerodynamic flutter in the zone of supercritical flow provides a potential mechanism for the energy dissipation necessary for transition from supercritical to subcritical flow and explains the high-frequency pure tone heard with flow limitation. PMID:4055608

  2. Controlled motion of domain walls in submicron amorphous wires

    NASA Astrophysics Data System (ADS)

    Ťibu, Mihai; Lostun, Mihaela; Allwood, Dan A.; Rotǎrescu, Cristian; Atiťoaie, Alexandru; Lupu, Nicoleta; Óvári, Tibor-Adrian; Chiriac, Horia

    2016-05-01

    Results on the control of the domain wall displacement in cylindrical Fe77.5Si7.5B15 amorphous glass-coated submicron wires prepared by rapid quenching from the melt are reported. The control methods have relied on conical notches with various depths, up to a few tens of nm, made in the glass coating and in the metallic nucleus using a focused ion beam (FIB) system, and on the use of small nucleation coils at one of the sample ends in order to apply magnetic field pulses aimed to enhance the nucleation of reverse domains. The notch-based method is used for the first time in the case of cylindrical ultrathin wires. The results show that the most efficient technique of controlling the domain wall motion in this type of samples is the simultaneous use of notches and nucleation coils. Their effect depends on wire diameter, notch depth, its position on the wire length, and characteristics of the applied pulse.

  3. Biomechanical and morphological study of a new elastic mesh (Ciberlastic) to repair abdominal wall defects.

    PubMed

    Calvo, B; Pascual, G; Peña, E; Pérez-Khöler, B; Rodríguez, M; Bellón, J M

    2016-06-01

    The aim of this study was to conduct a preclinical evaluation of the behaviour of a new type of abdominal LW prosthesis (Ciberlastic), which was designed with a non-absorbable elastic polyurethane monofilament (Assuplus, Assut Europe, Italy) to allow greater adaptability to mechanical area requirements and higher bio-mimicking with the newly formed surrounding tissues. Our hypothesis was that an increase in the elasticity of the mesh filament could improve the benefits of LW prostheses. To verify our hypothesis, we compared the short- and long-term behaviour of Ciberlastic and Optilene(®) elastic commercial meshes by repairing the partially herniated abdomen in New Zealand White rabbits. The implanted meshes were mechanically and histologically assessed at 14 and 180 days post-implant. We mechanically characterized the partially herniated repaired muscle tissue and also determined mesh shrinkage at different post-implant times. This was followed by a histological study in which the tissue incorporation process was analysed over time. The new prosthesis designed by our group achieved good behaviour that was similar to that of Optilene(®), one of the most popular LW prostheses on the market, with the added advantage of its elastic property. The mechanical properties are significantly lower than those of the polypropylene Optilene(®) mesh, and the new elastic mesh meets the basic mechanical requirements for positioning in the abdominal wall, which was also demonstrated by the absence of recurrences after implantation in the experimental model. We found that the growth of a connective tissue rich in collagen over the hernial defect and the proper deposit of the collagen fibres in the regenerated tissue substantially modified the original properties of the mesh, thereby increasing its biomechanical strength and making the whole tissue/mesh stiffer. PMID:26905037

  4. 3-D segmentation and quantitative analysis of inner and outer walls of thrombotic abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Lee, Kyungmoo; Yin, Yin; Wahle, Andreas; Olszewski, Mark E.; Sonka, Milan

    2008-03-01

    An abdominal aortic aneurysm (AAA) is an area of a localized widening of the abdominal aorta, with a frequent presence of thrombus. A ruptured aneurysm can cause death due to severe internal bleeding. AAA thrombus segmentation and quantitative analysis are of paramount importance for diagnosis, risk assessment, and determination of treatment options. Until now, only a small number of methods for thrombus segmentation and analysis have been presented in the literature, either requiring substantial user interaction or exhibiting insufficient performance. We report a novel method offering minimal user interaction and high accuracy. Our thrombus segmentation method is composed of an initial automated luminal surface segmentation, followed by a cost function-based optimal segmentation of the inner and outer surfaces of the aortic wall. The approach utilizes the power and flexibility of the optimal triangle mesh-based 3-D graph search method, in which cost functions for thrombus inner and outer surfaces are based on gradient magnitudes. Sometimes local failures caused by image ambiguity occur, in which case several control points are used to guide the computer segmentation without the need to trace borders manually. Our method was tested in 9 MDCT image datasets (951 image slices). With the exception of a case in which the thrombus was highly eccentric, visually acceptable aortic lumen and thrombus segmentation results were achieved. No user interaction was used in 3 out of 8 datasets, and 7.80 +/- 2.71 mouse clicks per case / 0.083 +/- 0.035 mouse clicks per image slice were required in the remaining 5 datasets.

  5. Optical Spin-Transfer-Torque-Driven Domain-Wall Motion in a Ferromagnetic Semiconductor

    NASA Astrophysics Data System (ADS)

    Ramsay, A. J.; Roy, P. E.; Haigh, J. A.; Otxoa, R. M.; Irvine, A. C.; Janda, T.; Campion, R. P.; Gallagher, B. L.; Wunderlich, J.

    2015-02-01

    We demonstrate optical manipulation of the position of a domain wall in a dilute magnetic semiconductor, GaMnAsP. Two main contributions are identified. First, photocarrier spin exerts a spin-transfer torque on the magnetization via the exchange interaction. The direction of the domain-wall motion can be controlled using the helicity of the laser. Second, the domain wall is attracted to the hot spot generated by the focused laser. Unlike magnetic-field-driven domain-wall depinning, these mechanisms directly drive domain-wall motion, providing an optical tweezerlike ability to position and locally probe domain walls.

  6. Accelerated motion corrected three‐dimensional abdominal MRI using total variation regularized SENSE reconstruction

    PubMed Central

    Atkinson, David; Buerger, Christian; Schaeffter, Tobias; Prieto, Claudia

    2015-01-01

    Purpose Develop a nonrigid motion corrected reconstruction for highly accelerated free‐breathing three‐dimensional (3D) abdominal images without external sensors or additional scans. Methods The proposed method accelerates the acquisition by undersampling and performs motion correction directly in the reconstruction using a general matrix description of the acquisition. Data are acquired using a self‐gated 3D golden radial phase encoding trajectory, enabling a two stage reconstruction to estimate and then correct motion of the same data. In the first stage total variation regularized iterative SENSE is used to reconstruct highly undersampled respiratory resolved images. A nonrigid registration of these images is performed to estimate the complex motion in the abdomen. In the second stage, the estimated motion fields are incorporated in a general matrix reconstruction, which uses total variation regularization and incorporates k‐space data from multiple respiratory positions. The proposed approach was tested on nine healthy volunteers and compared against a standard gated reconstruction using measures of liver sharpness, gradient entropy, visual assessment of image sharpness and overall image quality by two experts. Results The proposed method achieves similar quality to the gated reconstruction with nonsignificant differences for liver sharpness (1.18 and 1.00, respectively), gradient entropy (1.00 and 1.00), visual score of image sharpness (2.22 and 2.44), and visual rank of image quality (3.33 and 3.39). An average reduction of the acquisition time from 102 s to 39 s could be achieved with the proposed method. Conclusion In vivo results demonstrate the feasibility of the proposed method showing similar image quality to the standard gated reconstruction while using data corresponding to a significantly reduced acquisition time. Magn Reson Med, 2015. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of

  7. Changes in muscle strength and pain in response to surgical repair of posterior abdominal wall disruption followed by rehabilitation

    PubMed Central

    Hemingway, A; Herrington, L; Blower, A

    2003-01-01

    Background: Posterior abdominal wall deficiency (PAWD) is a tear in the external oblique aponeurosis or the conjoint tendon causing a posterior wall defect at the medial end of the inguinal canal. It is often known as sportsman's hernia and is believed to be caused by repetitive stress. Objective: To assess lower limb and abdominal muscle strength of patients with PAWD before intervention compared with matched controls; to evaluate any changes following surgical repair and rehabilitation. Methods: Sixteen subjects were assessed using a questionnaire, isokinetic testing of the lower limb strength, and pressure biofeedback testing of the abdominals. After surgery and a six week rehabilitation programme, the subjects were re-evaluated. A control group were assessed using the same procedure. Results: Quadriceps and hamstrings strength was not affected by this condition. A deficit hip muscle strength was found on the affected limb before surgery, which was significant for the hip flexors (p = 0.05). Before surgery, 87% of the patients compared with 20% of the controls failed the abdominal obliques test. Both the injured and non-injured sides had improved significantly in strength after surgery and rehabilitation. The strength of the abdominal obliques showed the most significant improvement over the course of the rehabilitation programme. Conclusions: Lower limb muscle strength may have been reduced as the result of disuse atrophy or pain inhibition. Abdominal oblique strength was deficient in the injured patients and this compromises rotational control of the pelvis. More sensitive investigations (such as electromyography) are needed to assess the link between abdominal oblique function and groin injury. PMID:12547744

  8. A randomized controlled experimental study comparing chitosan coated polypropylene mesh and Proceed™ mesh for abdominal wall defect closure

    PubMed Central

    Jayanth, S.T.; Pulimood, Anna; Abraham, Deepak; Rajaram, A.; Paul, M.J.; Nair, Aravindan

    2015-01-01

    Background Abdominal wall defects and hernias are commonly repaired with synthetic or biological materials. Adhesions and recurrences are a common problem. A study was conducted to compare Chitosan coated polypropylene mesh and a polypropylene–polydioxanone composite with oxidized cellulose coating mesh (Proceed™) in repair of abdominal wall defect in a Rabbit hernia model. Methods A randomized controlled experimental study was done on twelve New Zealand white rabbits. A ventral abdominal defect was created in each of the rabbits. The rabbits were divided into two groups. In one group the defect was repaired with Chitosan coated polypropylene mesh and Proceed mesh™ in the other. The rabbits were operated in two phases. They were followed up at four weeks and twelve weeks respectively after which the rabbits were sacrificed. They were evaluated by open exploration and histopathological examination. Their efficacy in reducing adhesion and ability of remodeling and tissue integration were studied. Results There was no statistical significance in the area of adhesion, the force required to remove the adhesions, tissue integration and remodeling between Chitosan and Proceed™ group. Histological analysis revealed that the inflammatory response, fibrosis, material degradation and remodeling were similar in both the groups. There were no hernias, wound infection or dehiscence in any of the studied animals. Conclusion Chitosan coated polypropylene mesh was found to have similar efficacy to Proceed™ mesh. Chitosan coated polypropylene mesh, can act as an anti adhesive barrier when used in the repair of incisional hernias and abdominal wall defects. PMID:26594357

  9. Delay in diagnosis and lessons learnt from a case of abdominal wall abscess caused by fishbone perforation

    PubMed Central

    Shanmugam, V; Badrinath, K; Dube, M; Panto, P

    2015-01-01

    Complications following foreign body (FB) ingestion are an uncommon clinical problem. A 59-year-old man presented with a 4-week history of left iliac fossa pain and 1 episode of dark red blood mixed with stools. Inflammatory markers were elevated, and computed tomography (CT) of the abdomen and pelvis showed an ill defined abdominal wall inflammatory collection in close contact with the small bowel loops. He was treated with antibiotics, and follow-up CT, colonoscopy and small bowel enema were mostly unremarkable. The patient presented again ten months later with left iliac fossa cellulitis and fever. Multiplanar CT (the patient’s fourth scan) demonstrated a 10cm abdominal wall collection with a linear hyperdense structure in the collection. The radiologists suspected a FB and on close scrutiny of the previous scans, they noted it to have been present on all of them. A targeted incision led to the removal of a 3cm fishbone from the collection. This case highlights the need to consider the possibility of a FB being the underlying cause in any unexplained intra-abdominal or abdominal wall inflammatory process so that the diagnosis is made in a timely manner. PMID:26263825

  10. Refining the course of the thoracolumbar nerves: a new understanding of the innervation of the anterior abdominal wall.

    PubMed

    Rozen, W M; Tran, T M N; Ashton, M W; Barrington, M J; Ivanusic, J J; Taylor, G I

    2008-05-01

    Previous descriptions of the thoracolumbar spinal nerves innervating the anterior abdominal wall have been inconsistent. With modern surgical and anesthetic techniques that involve or may damage these nerves, an improved understanding of the precise course and variability of this anatomy has become increasingly important. The course of the nerves of the anterior abdominal is described based on a thorough cadaveric study and review of the literature. Twenty human cadaveric hemi-abdominal walls were dissected to map the course of the nerves of the anterior abdominal wall. Dissection included a comprehensive tracing of nerves and their branches from their origins in five specimens. The branching pattern and course of all nerves identified were described. All thoracolumbar nerves that innervate the anterior abdominal wall were found to travel as multiple mixed segmental nerves, which branch and communicate widely within the transversus abdominis plane (TAP). This communication may occur at multiple locations, including large branch communications anterolaterally (intercostal plexus), and in plexuses that run with the deep circumflex iliac artery (DCIA) (TAP plexus) and the deep inferior epigastric artery (DIEA) (rectus sheath plexus). Rectus abdominis muscle is innervated by segments T6-L1, with a constant branch from L1. The umbilicus is always innervated by a branch of T10. As such, identification or damage to individual nerves in the TAP or within rectus sheath is unlikely to involve single segmental nerves. An understanding of this anatomy may contribute to explaining clinical outcomes and preventing complications, following TAP blocks for anesthesia and DIEA perforator flaps for breast reconstruction. PMID:18428988

  11. Chest Wall Motion during Speech Production in Patients with Advanced Ankylosing Spondylitis

    ERIC Educational Resources Information Center

    Kalliakosta, Georgia; Mandros, Charalampos; Tzelepis, George E.

    2007-01-01

    Purpose: To test the hypothesis that ankylosing spondylitis (AS) alters the pattern of chest wall motion during speech production. Method: The pattern of chest wall motion during speech was measured with respiratory inductive plethysmography in 6 participants with advanced AS (5 men, 1 woman, age 45 plus or minus 8 years, Schober test 1.45 plus or…

  12. Clinical applications of a quantitative analysis of regional lift ventricular wall motion

    NASA Technical Reports Server (NTRS)

    Leighton, R. F.; Rich, J. M.; Pollack, M. E.; Altieri, P. I.

    1975-01-01

    Observations were summarized which may have clinical application. These were obtained from a quantitative analysis of wall motion that was used to detect both hypokinesis and tardokinesis in left ventricular cineangiograms. The method was based on statistical comparisons with normal values for regional wall motion derived from the cineangiograms of patients who were found not to have heart disease.

  13. Domain wall motion driven by adiabatic spin transfer torque through excitation of nonlinear dynamics

    NASA Astrophysics Data System (ADS)

    Wang, D.; Dong, Yulan; Yan, Zhou; Wang, Xi-guang; He, Jun; Guo, Guang-hua

    2016-05-01

    Domain wall dynamics under the joint action of a linearly polarized microwave magnetic field and spin transfer torque was analysed in terms of the domain wall collective coordinates. It was found that a microwave-assisted steady domain wall motion driven by adiabatic spin transfer torque can be adequately described by three domain wall collective coordinates. Analytical expression for the domain wall velocity showed that there are two contributions to the steady domain wall motion. One is derived from the nonlinear oscillation of domain wall width excited by the microwave field, and the other is from the heterodyne process between the width oscillation and the microwave field. The former always propels a domain wall to move in the positive direction, which is defined as the direction of the applied current. The latter contribution to the domain wall velocity can be positive or negative, depending on the polarization of the microwave field. The final domain wall velocity is determined by the competition between those two contributions, which indicates that by simply changing the polarization of the microwave field, the direction of the domain wall motion can be reversed. Our analysis demonstrated that the characteristics of domain wall motion can be tuned by selective excitation of nonlinear domain wall dynamics.

  14. Cutaneous squamous cell carcinoma in the lateral abdominal wall of local Libyan ewes

    PubMed Central

    Tmumen, S.K.; Al-Azreg, S.A.; Abushhiwa, M.H.; Alkoly, M.A.; Bennour, E.M.; Al­Attar, S.R.

    2016-01-01

    Gross and histopathological features of surgically excised squamous cell carcinomas (SCC) observed in thirteen local Libyan ewes were reported. The age of the ewes enrolled in the current study ranged from 2 to 3 years. The cases were admitted to private veterinary clinics in south-western region of Tripoli, Libya, during the period between July 2014 and October 2015. All lesions were located in the right and left lateral abdominal wall (caudo-ventrally) with a size range of 8 to 11cm in diameter. The tumor masses have been removed by surgical excision. The histopathological examination of surgically excised masses has revealed the characteristic cell nests of SCC showing central keratinization and hyalinization with presence of apoptotic bodies, fattened keratinocytes, and a heavy interstitial infiltration of neutrophils and lymphocytes. The follow up of the cases showed no signs of tumor reoccurrence. In conclusion, SCC in Libyan sheep affects mainly the woolless areas and can be successfully removed by surgical excision. PMID:27622155

  15. Active behavior of abdominal wall muscles: Experimental results and numerical model formulation.

    PubMed

    Grasa, J; Sierra, M; Lauzeral, N; Muñoz, M J; Miana-Mena, F J; Calvo, B

    2016-08-01

    In the present study a computational finite element technique is proposed to simulate the mechanical response of muscles in the abdominal wall. This technique considers the active behavior of the tissue taking into account both collagen and muscle fiber directions. In an attempt to obtain the computational response as close as possible to real muscles, the parameters needed to adjust the mathematical formulation were determined from in vitro experimental tests. Experiments were conducted on male New Zealand White rabbits (2047±34g) and the active properties of three different muscles: Rectus Abdominis, External Oblique and multi-layered samples formed by three muscles (External Oblique, Internal Oblique, and Transversus Abdominis) were characterized. The parameters obtained for each muscle were incorporated into a finite strain formulation to simulate active behavior of muscles incorporating the anisotropy of the tissue. The results show the potential of the model to predict the anisotropic behavior of the tissue associated to fibers and how this influences on the strain, stress and generated force during an isometric contraction. PMID:27111629

  16. Cutaneous squamous cell carcinoma in the lateral abdominal wall of local Libyan ewes.

    PubMed

    Tmumen, S K; Al-Azreg, S A; Abushhiwa, M H; Alkoly, M A; Bennour, E M; Al Attar, S R

    2016-01-01

    Gross and histopathological features of surgically excised squamous cell carcinomas (SCC) observed in thirteen local Libyan ewes were reported. The age of the ewes enrolled in the current study ranged from 2 to 3 years. The cases were admitted to private veterinary clinics in south-western region of Tripoli, Libya, during the period between July 2014 and October 2015. All lesions were located in the right and left lateral abdominal wall (caudo-ventrally) with a size range of 8 to 11cm in diameter. The tumor masses have been removed by surgical excision. The histopathological examination of surgically excised masses has revealed the characteristic cell nests of SCC showing central keratinization and hyalinization with presence of apoptotic bodies, fattened keratinocytes, and a heavy interstitial infiltration of neutrophils and lymphocytes. The follow up of the cases showed no signs of tumor reoccurrence. In conclusion, SCC in Libyan sheep affects mainly the woolless areas and can be successfully removed by surgical excision. PMID:27622155

  17. Long-term anisotropic mechanical response of surgical meshes used to repair abdominal wall defects.

    PubMed

    Hernández-Gascón, B; Peña, E; Pascual, G; Rodríguez, M; Bellón, J M; Calvo, B

    2012-01-01

    Routine hernia repair surgery involves the implant of synthetic mesh. However, this type of procedure may give rise to pain and bowel incarceration and strangulation, causing considerable patient disability. The purpose of this study was to compare the long-term behaviour of three commercial meshes used to repair the partially herniated abdomen in New Zealand White rabbits: the heavyweight (HW) mesh, Surgipro(®) and lightweight (LW) mesh, Optilene(®), both made of polypropylene (PP), and a mediumweight (MW) mesh, Infinit(®), made of polytetrafluoroethylene (PTFE). The implanted meshes were mechanical and histological assessed at 14, 90 and 180 days post-implant. This behaviour was compared to the anisotropic mechanical behaviour of the unrepaired abdominal wall in control non-operated rabbits. Both uniaxial mechanical tests conducted in craneo-caudal and perpendicular directions and histological findings revealed substantial collagen growth over the repaired hernial defects causing stiffness in the repair zone, and thus a change in the original properties of the meshes. The mechanical behaviour of the healthy tissue in the craneo-caudal direction was not reproduced by any of the implanted meshes after 14 days or 90 days of implant, whereas in the perpendicular direction, SUR and OPT achieved similar behaviour. From a mechanical standpoint, the anisotropic PP-lightweight meshes may be considered a good choice in the long run, which correlates with the structure of the regenerated tissue. PMID:22100101

  18. Urinary Bladder Adenocarcinoma Metastatic to the Abdominal Wall: Report of a Case with Cytohistologic Correlation.

    PubMed

    Nath, Vikas; Baliga, Mithra

    2016-01-01

    We report a case of adenocarcinoma metastatic to the abdominal wall in a 71-year-old man with a history of primary bladder adenocarcinoma. CT-guided core biopsy was performed; imprints and histologic sections showed malignant glands lined by tumor cells with hyperchromatic nuclei and prominent nucleoli, infiltrating through skeletal muscle. Immunohistochemistry revealed positivity for CK7, membranous/cytoplasmic β-catenin, caudal-type homeobox transcription factor 2 (CDX2), and α-methylacyl coenzyme A racemase and negativity for CK20, p63, prostate-specific antigen (PSA), and prostate-specific acid phosphatase (PSAP). These findings were interpreted as metastatic adenocarcinoma, consistent with bladder primary. Primary bladder adenocarcinoma is a rare malignancy arising within glandular metaplasia and is associated with cystitis cystica and cystitis glandularis. Predisposing factors include bladder exstrophy, schistosomiasis, and other causes of chronic bladder irritation. This tumor is divided into intestinal, clear cell, and signet ring cell subtypes. Treatment involves radical cystectomy with pelvic lymph node dissection, and prognosis is unfavorable. Primary bladder adenocarcinoma should be differentiated from urachal adenocarcinoma, which arises from urachal remnants near the bladder dome, and secondary adenocarcinoma, or vesical involvement by adenocarcinoma from a different primary. CK7, CK20, CDX2, thrombomodulin, and β-catenin can help distinguish primary bladder adenocarcinoma from colonic adenocarcinoma; PSA and PSAP can help distinguish primary bladder adenocarcinoma from prostate adenocarcinoma. PMID:27006847

  19. [A Case of Abdominal Wall Desmoid Tumor after Radical Nephrectomy for Renal Cancer].

    PubMed

    Ohtake, Shinji; Namura, Kazuhiro; Fujikawa, Atsushi; Sawada, Takuto; Ohta, Junichi; Moriyama, Masatoshi; Hayashi, Hiroyuki

    2015-09-01

    A 71-year-old man with a right renal tumor underwent nephrectomy. The procedure was converted from laparoscopy to open surgery due to profound bleeding from the renal vein. Pathological diagnosis was clear cell carcinoma G2pT3b v1 ly1 INFα. Three years after surgery, a 5 cm tumor in the abdominal wall was found on computed tomography (CT). A mild uptake was shown on positron emission tomography/CT and as the tumor was located near the surgical wound, recurrence of the renal cell carcinoma was suspected. However, desmoid tumor was suggested by the pathological examination of the tumor biopsy. En-bloc resection of the mass was carried out and the pathological examination showed an array of proliferating and tangling atypical spindle-shaped tumor cells. Immunohistochemical staining of the tumor cells was positive for vimentin, but negative for CD34, c-kit, and s100. Pathological diagnosis was desmoid tumor. There has been no recurrence so far. Desmoid tumor, despite its extremely low incidence, should be considered in a postoperative neoplasm. PMID:26497861

  20. Urinary Bladder Adenocarcinoma Metastatic to the Abdominal Wall: Report of a Case with Cytohistologic Correlation

    PubMed Central

    Baliga, Mithra

    2016-01-01

    We report a case of adenocarcinoma metastatic to the abdominal wall in a 71-year-old man with a history of primary bladder adenocarcinoma. CT-guided core biopsy was performed; imprints and histologic sections showed malignant glands lined by tumor cells with hyperchromatic nuclei and prominent nucleoli, infiltrating through skeletal muscle. Immunohistochemistry revealed positivity for CK7, membranous/cytoplasmic β-catenin, caudal-type homeobox transcription factor 2 (CDX2), and α-methylacyl coenzyme A racemase and negativity for CK20, p63, prostate-specific antigen (PSA), and prostate-specific acid phosphatase (PSAP). These findings were interpreted as metastatic adenocarcinoma, consistent with bladder primary. Primary bladder adenocarcinoma is a rare malignancy arising within glandular metaplasia and is associated with cystitis cystica and cystitis glandularis. Predisposing factors include bladder exstrophy, schistosomiasis, and other causes of chronic bladder irritation. This tumor is divided into intestinal, clear cell, and signet ring cell subtypes. Treatment involves radical cystectomy with pelvic lymph node dissection, and prognosis is unfavorable. Primary bladder adenocarcinoma should be differentiated from urachal adenocarcinoma, which arises from urachal remnants near the bladder dome, and secondary adenocarcinoma, or vesical involvement by adenocarcinoma from a different primary. CK7, CK20, CDX2, thrombomodulin, and β-catenin can help distinguish primary bladder adenocarcinoma from colonic adenocarcinoma; PSA and PSAP can help distinguish primary bladder adenocarcinoma from prostate adenocarcinoma. PMID:27006847

  1. Non-traumatic hernia of the lateral abdominal wall in a patient infected with the human immunodeficiency virus.

    PubMed

    Fan, Z; Pan, J; Liu, X; Zhuang, C; Ren, J; Yu, H; Tang, S; Wang, S

    2016-07-01

    Introduction There are several classifications for abdominal hernias, and a non-traumatic lateral wall hernia (LAWH) is a rare type. We report the first case of a patient with LAWH infected with the human immunodeficiency virus (HIV). Case History A 53-year-old HIV-infected male presented with an abdominal mass. The patient had a history of treatment with combination antiretroviral therapy. A LAWH was diagnosed based on physical examination and findings of computed tomography. Open mesh repair was undertaken successfully. The patient had no evidence of a recurrent hernia during 11 months of follow-up. Conclusions High intra-abdominal pressure and weak connective tissue can lead to LAWHs. Antiretroviral therapy and lipodystrophy can cause LAWHs in HIV-infected patients. PMID:27241599

  2. Three Dimensional Motion Compensation for Real-Time MRI Guided Focused Ultrasound Treatment of Abdominal Organs

    NASA Astrophysics Data System (ADS)

    Ries, M.; De Senneville, B. D.; Roujol, S.; Hey, S.; Maclair, G.; Köhler, M. O.; Quesson, B.; Moonen, C. T. W.

    2010-03-01

    MR-guided high intensity focused ultrasound (HIFU) has evolved into a promising non-invasive technique for the ablation of pathological tissue in abdominal organs. However, since the high perfusion rates of these organs lead to effective cooling, sustained sonications of 30-90 s are required to achieve a sufficiently high temperature elevation to induce necrosis. This is complicated by the constant displacement of the target due to the respiratory cycle. This study proposes sub-second 3D HIFU-beam steering under MR-guidance for the near real-time compensation of respiratory motion as a possible solution. The target position is observed in 3D space by coupling rapid 2D MR-imaging with prospective slice tracking (PST) based on pencil-beam navigator echoes. Continuous real-time image processing provides temperature maps, thermal dose estimates and the target position at a frequency of 10 Hz and an update latency of less than 120 ms. The suggested method is evaluated with phantom experiments and its feasibility is verified in-vivo with an ablation experiment on a porcine kidney where it allows to achieve a thermal energy deposition which is comparable to static control experiments.

  3. Electric-field-controlled suppression of Walker breakdown and chirality switching in magnetic domain wall motion

    NASA Astrophysics Data System (ADS)

    Chen, Hong-Bo; Li, You-Quan

    2016-07-01

    We theoretically study the dynamics of a magnetic domain wall controlled by an electric field in the presence of the spin flexoelectric interaction. We reveal that this interaction generates an effective spin torque and results in significant changes in the current-driven domain wall motion. In particular, the electric field can stabilize the domain wall motion, leading to strong suppression of the current-induced Walker breakdown and thus allowing a higher maximum wall velocity. We can furthermore use this electric-field control to efficiently switch the chirality of a moving domain wall in the steady regime.

  4. Micromagnetic analysis of current-induced domain wall motion in a bilayer nanowire with synthetic antiferromagnetic coupling

    NASA Astrophysics Data System (ADS)

    Komine, Takashi; Aono, Tomosuke

    2016-05-01

    We demonstrate current-induced domain wall motion in bilayer nanowire with synthetic antiferromagnetic (SAF) coupling by modeling two body problems for motion equations of domain wall. The influence of interlayer exchange coupling and magnetostatic interactions on current-induced domain wall motion in SAF nanowires was also investigated. By assuming the rigid wall model for translational motion, the interlayer exchange coupling and the magnetostatic interaction between walls and domains in SAF nanowires enhances domain wall speed without any spin-orbit-torque. The enhancement of domain wall speed was discussed by energy distribution as a function of wall angle configuration in bilayer nanowires.

  5. Antiferromagnetic Domain Wall Motion Driven by Spin-Orbit Torques.

    PubMed

    Shiino, Takayuki; Oh, Se-Hyeok; Haney, Paul M; Lee, Seo-Won; Go, Gyungchoon; Park, Byong-Guk; Lee, Kyung-Jin

    2016-08-19

    We theoretically investigate the dynamics of antiferromagnetic domain walls driven by spin-orbit torques in antiferromagnet-heavy-metal bilayers. We show that spin-orbit torques drive antiferromagnetic domain walls much faster than ferromagnetic domain walls. As the domain wall velocity approaches the maximum spin-wave group velocity, the domain wall undergoes Lorentz contraction and emits spin waves in the terahertz frequency range. The interplay between spin-orbit torques and the relativistic dynamics of antiferromagnetic domain walls leads to the efficient manipulation of antiferromagnetic spin textures and paves the way for the generation of high frequency signals from antiferromagnets. PMID:27588878

  6. [Influence of laser -- infrared irradiation on local complications of early postoperative period in hernias of anterior abdominal wall].

    PubMed

    Gasymov, E M

    2005-01-01

    Results of laser-infrared irradiation (LIRI) of postoperative wound after surgical treatment of recurrent hernias of anterior abdominal wall were analyzed. LIRI decreased number of local complications in early postoperative period in patients both with recurrent and primary hernias. The method was more effective for the treatment of local complication in patients with recurrent hernia that is confirmed by reduced of frequency of infiltrates, seromas and suppurations. PMID:16247383

  7. Successful Treatment of Mesenteric Varices After Living Donor Liver Transplantation with Retrograde Transvenous Obliteration Via an Abdominal Wall Vein

    SciTech Connect

    Ikeda, Osamu Tamura, Yoshitaka; Nakasone, Yutaka; Yamashita, Yasuyuki; Okajima, Hideaki; Asonuma, Katsuhiro; Inomata, Yukihiro

    2010-06-15

    Balloon-occluded retrograde transvenous obliteration is an established treatment for gastric varices; it has been used more rarely to treat mesenteric varices. We report a 12-year-old girl who had received a living donor liver transplant and suffered melena due to ruptured mesenteric varices. We addressed treatment of the mesenteric varices by retrograde transvenous obliteration of an abdominal wall collateral vein detected by superior mesenteric arteriography.

  8. Abdominal CT scan

    MedlinePlus

    ... results may also be due to: Abdominal aortic aneurysm Abscesses Appendicitis Bowel wall thickening Retroperitoneal fibrosis Renal ... Livingstone; 2014:chap 4. Read More Abdominal aortic aneurysm Abdominal aortic aneurysm repair - open Abscess Acute cholecystitis ...

  9. Surgically placed abdominal wall catheters on postoperative analgesia and outcomes after living liver donation.

    PubMed

    Khan, James; Katz, Joel; Montbriand, Janice; Ladak, Salima; McCluskey, Stuart; Srinivas, Coimbatore; Ko, Raynauld; Grant, David; Bradbury, Ashleene; LeManach, Yannick; Clarke, Hance

    2015-04-01

    Living donor liver resections are associated with significant postoperative pain. Epidural analgesia is the gold standard for postoperative pain management, although it is often refused or contraindicated. Surgically placed abdominal wall catheters (AWCs) are a novel pain modality that can potentially provide pain relief for those patients who are unable to receive an epidural. A retrospective review was performed at a single center. Patients were categorized according to their postoperative pain modality: intravenous (IV) patient-controlled analgesia (PCA), AWCs with IV PCA, or patient-controlled epidural analgesia (PCEA). Pain scores, opioid consumption, and outcomes were compared for the first 3 postoperative days. Propensity score matches (PSMs) were performed to adjust for covariates and to confirm the primary analysis. The AWC group had significantly lower mean morphine-equivalent consumption on postoperative day 3 [18.1 mg, standard error (SE)=3.1 versus 28.2 mg, SE=3.0; P=0.02] and mean cumulative morphine-equivalent consumption (97.2 mg, SE=7.2 versus 121.0 mg, SE=9.1; P=0.04) in comparison with the IV PCA group; the difference in cumulative-morphine equivalent remained significant in the PSMs. AWC pain scores were higher than those in the PCEA group and were similar to the those in the IV PCA group. The AWC group had a lower incidence of pruritus and a shorter hospital stay in comparison with the PCEA group and had a lower incidence of sedation in comparison with both groups. Time to ambulation, nausea, and vomiting were comparable among all 3 groups. The PSMs confirmed all results except for a decrease in the length of stay in comparison with PCEA. AWCs may be an alternative to epidural analgesia after living donor liver resections. Randomized trials are needed to verify the benefits of AWCs, including the safety and adverse effects. PMID:25546011

  10. A Randomized Controlled Trial of Lorazepam to Reduce Liver Motion in Patients Receiving Upper Abdominal Radiation Therapy

    SciTech Connect

    Tsang, Derek S.; Voncken, Francine E.M.; Tse, Regina V.; Sykes, Jenna; Wong, Rebecca K.S.; Dinniwell, Rob E.; Kim, John; Ringash, Jolie; Brierley, James D.; Cummings, Bernard J.; Brade, Anthony; Dawson, Laura A.

    2013-12-01

    Purpose: Reduction of respiratory motion is desirable to reduce the volume of normal tissues irradiated, to improve concordance of planned and delivered doses, and to improve image guided radiation therapy (IGRT). We hypothesized that pretreatment lorazepam would lead to a measurable reduction of liver motion. Methods and Materials: Thirty-three patients receiving upper abdominal IGRT were recruited to a double-blinded randomized controlled crossover trial. Patients were randomized to 1 of 2 study arms: arm 1 received lorazepam 2 mg by mouth on day 1, followed by placebo 4 to 8 days later; arm 2 received placebo on day 1, followed by lorazepam 4 to 8 days later. After tablet ingestion and daily radiation therapy, amplitude of liver motion was measured on both study days. The primary outcomes were reduction in craniocaudal (CC) liver motion using 4-dimensional kV cone beam computed tomography (CBCT) and the proportion of patients with liver motion ≤5 mm. Secondary endpoints included motion measured with cine magnetic resonance imaging and kV fluoroscopy. Results: Mean relative and absolute reduction in CC amplitude with lorazepam was 21% and 2.5 mm respectively (95% confidence interval [CI] 1.1-3.9, P=.001), as assessed with CBCT. Reduction in CC amplitude to ≤5 mm residual liver motion was seen in 13% (95% CI 1%-25%) of patients receiving lorazepam (vs 10% receiving placebo, P=NS); 65% (95% CI 48%-81%) had reduction in residual CC liver motion to ≤10 mm (vs 52% with placebo, P=NS). Patients with large respiratory movement and patients who took lorazepam ≥60 minutes before imaging had greater reductions in liver CC motion. Mean reductions in liver CC amplitude on magnetic resonance imaging and fluoroscopy were nonsignificant. Conclusions: Lorazepam reduces liver motion in the CC direction; however, average magnitude of reduction is small, and most patients have residual motion >5 mm.

  11. SU-E-J-133: Evaluation of Inter- and Intra-Fractional Pancreas Tumor Residual Motions with Abdominal Compression

    SciTech Connect

    Li, Y; Shi, F; Tian, Z; Jia, X; Meyer, J; Jiang, S; Mao, W

    2014-06-01

    Purpose: Abdominal compression (AC) has been widely used to reduce pancreas motion due to respiration for pancreatic cancer patients undergoing stereotactic body radiotherapy (SBRT). However, the inter-fractional and intra-fractional patient motions may degrade the treatment. The purpose of this work is to study daily CBCT projections and 4DCT to evaluate the inter-fractional and intra-fractional pancreatic motions. Methods: As a standard of care at our institution, 4D CT scan was performed for treatment planning. At least two CBCT scans were performed for daily treatment. Retrospective studies were performed on patients with implanted internal fiducial markers or surgical clips. The initial motion pattern was obtained by extracting marker positions on every phase of 4D CT images. Daily motions were presented by marker positions on CBCT scan projection images. An adaptive threshold segmentation algorithm was used to extract maker positions. Both marker average positions and motion ranges were compared among three sets of scans, 4D CT, positioning CBCT, and conformal CBCT, for inter-fractional and intra-fractional motion variations. Results: Data from four pancreatic cancer patients were analyzed. These patients had three fiducial markers implanted. All patients were treated by an Elekta Synergy with single fraction SBRT. CBCT projections were acquired by XVI. Markers were successfully detected on most of the projection images. The inter-fractional changes were determined by 4D CT and the first CBCT while the intra-fractional changes were determined by multiple CBCT scans. It is found that the average motion range variations are within 2 mm, however, the average marker positions may drift by 6.5 mm. Conclusion: The patients respiratory motion variation for pancreas SBRT with AC was evaluated by detecting markers from CBCT projections and 4DCT, both the inter-fraction and intra-fraction motion range change is small but the drift of marker positions may be comparable

  12. Increased Expression of Lamin A/C Correlate with Regions of High Wall Stress in Abdominal Aortic Aneurysms

    PubMed Central

    Malkawi, Amir; Pirianov, Grisha; Torsney, Evelyn; Chetter, Ian; Sakalihasan, Natzi; Loftus, Ian M.; Nordon, Ian; Huggins, Christopher; Charolidi, Nicoletta; Thompson, Matt; Xu, Xie Yun; Cockerill, Gillian W.

    2015-01-01

    Background Since aortic diameter is the most ­significant risk factor for rupture, we sought to identify stress-dependent changes in gene expression to illuminate novel molecular processes in aneurysm rupture. Materials and Methods We constructed finite element maps of abdominal computerized tomography scans (CTs) of seven abdominal aortic aneurysm (AAA) patients to map wall stress. Paired biopsies from high- and low-stress areas were collected at surgery using vascular landmarks as coordinates. Differential gene expression was evaluated by Illumina Array analysis, using the whole genome DNA-mediated, annealing, selection, extension, and ligation (DASL) gene chip (n = 3 paired samples). Results The sole significant candidate from this analysis, Lamin A/C, was validated at the protein level, using western blotting. Lamin A/C expression in the inferior mesenteric vein (IMV) of AAA patients was compared to a control group and in aortic smooth muscle cells in culture in response to physiological pulsatile stretch. ­Areas of high wall stress (n = 7) correlate to those ­regions which have the thinnest walls [778 µm (585–1120 µm)] in comparison to areas of lowest wall stress [1620 µm (962–2919 µm)]. Induced expression of Lamin A/C ­correlated with areas of high wall stress from AAAs but was not significantly induced in the IMV from AAA patients compared to controls (n = 16). Stress-induced expression of Lamin A/C was mimicked by exposing aortic smooth muscle cells to prolonged pulsatile stretch. Conclusion Lamin A/C protein is specifically increased in areas of high wall stress in AAA from patients, but is not increased on other vascular beds of aneurysm patients, suggesting that its elevation may be a compensatory response to the pathobiology leading to aneurysms. PMID:27175366

  13. Bilateral photon deficient area along lateral abdominal wall in a Tc-99m DTPA renogram. A sign of massive ascites.

    PubMed

    Shih, W J; Marsano, L S

    1993-07-01

    A patient with congestive heart failure and hepatic and renal dysfunction underwent Tc-99m DTPA renal scintigraphic studies in which persistent cardiac blood pool activity, hepatic arterialization, and a longitudinal photon deficient area in each side of the abdominal wall were observed. The increase in hepatic artery inflow was believed to be due to a decrease in portal inflow of the liver. The elevation of portal pressure secondary to heart failure is attributable to the decrease in portal inflow of the liver; this phenomenon could account for the hepatic arterialization. Progressive renal dysfunction with high body background resulted in demonstrable ascites as photon deficient areas. Scintigraphic findings of hepatic arterialization plus an abdominal photon deficient area reflect severe heart failure and renal dysfunction. PMID:8344036

  14. Transient motion of a confined rarefied gas due to wall heating or cooling

    NASA Technical Reports Server (NTRS)

    Wadsworth, Dean C.; Erwin, Daniel A.; Muntz, E. P.

    1993-01-01

    The direct Monte Carlo method is used to simulate the transient motion of a confined rarefied gas as a container wall is rapidly heated or cooled. Results show that, for the rapid wall temperature changes, the gas response is better measured by an acoustic, rather than conduction, timescale, with steady state conditions being achieved after about ten wave crossing times.

  15. Spin-wave-driven high-speed domain-wall motions in soft magnetic nanotubes

    SciTech Connect

    Yang, Jaehak; Yoo, Myoung-Woo; Kim, Sang-Koog

    2015-10-28

    We report on a micromagnetic simulation study of interactions between propagating spin waves and a head-to-head domain wall in geometrically confined magnetic nanotubes. We found that incident spin waves of specific frequencies can lead to sufficiently high-speed (on the order of a few hundreds of m/s or higher) domain-wall motions in the same direction as that of the incident spin-waves. The domain-wall motions and their speed vary remarkably with the frequency and the amplitude of the incident spin-waves. High-speed domain-wall motions originate from the transfer torque of spin waves' linear momentum to the domain wall, through the partial or complete reflection of the incident spin waves from the domain wall. This work provides a fundamental understanding of the interaction of the spin waves with a domain wall in the magnetic nanotubes as well as a route to all-magnetic control of domain-wall motions in the magnetic nanoelements.

  16. Venous malformations of the anterior abdominal wall in blue rubber bleb naevus syndrome: implications for antenatal and intrapartum management

    PubMed Central

    Cauldwell, Matthew; Kyle, Pippa; Treharne, Ian; Wong, Terry; Holden, Simon T; Nelson-Piercy, Catherine

    2011-01-01

    Blue rubber bleb naevus syndrome (BRBNS) is a rare vascular disorder characterized by rubbery blue–purple cutaneous nodules that are histologically thin-walled dilated vascular spaces. The exact inheritance of the disease in unknown but in cases of familial recurrence, there appears to be a pattern of autosomal dominant inheritance. The vascular lesions may manifest in any organ system but tend to predominate in the gastrointestinal tract (GI). There are only a handful of cases reported in the literature, but reported complications arising from the naevi include sponatenous GI bleeding requiring laparotomy and blood transfusion and the development of large naevi in the cervix thus preventing vaginal delivery. In this case we describe a patient with known BRBNS who developed symptomatic anaemia during her pregnancy which required antenatal admission and blood transfusion. She was managed expectantly in a multidisciplinary setting by obstetricians, gastroenterologists and an obstetric physician with the aim of a vaginal delivery. Nevertheless, she had an elective caesarean section at term for breech presentation. Surgery was complicated by the unexpected finding of venous malformations within the abdominal wall musculature and subcutaneous fat that resulted in a primary haemorrhage and required urgent blood transfusion. The patient made a good postoperative recovery and had a healthy male infant who at birth displayed no external features of BRBNS. This report demonstrates for the first time the appearance of naevi in the abdominal wall and the important considerations that need to be made regarding mode of delivery and future pregnancies.

  17. Blood flow and wall motion in an idealized left ventricle

    NASA Astrophysics Data System (ADS)

    Tavoularis, Stavros; Doyle, Matthew; Bourgault, Yves

    2006-11-01

    During diastole of the heart, the left ventricle (LV) expands as a result of both incoming blood flow and wall material relaxation. In this work, we simulate both of these effects, along with the fluid-structure interaction between the blood and the heart wall. As a first step leading to more realistic studies, we approximate the LV by a prolate ellipsoid and the valves by cylindrical tubes. The mitral valve is open, allowing blood to enter the LV, whereas the aortic valve is closed. To account for the effects of muscle fibers in the heart wall, we model the wall as a multi-layered orthotropic linear elastic material with different material properties in the fiber, sheet, and sheet-normal directions within each layer. Results will be presented for this idealized configuration, while simulations of blood flow in realistic canine left and right ventricles are currently underway.

  18. Domain wall motion driven by spin Hall effect—Tuning with in-plane magnetic anisotropy

    SciTech Connect

    Rushforth, A. W.

    2014-04-21

    This letter investigates the effects of in-plane magnetic anisotropy on the current induced motion of magnetic domain walls in systems with dominant perpendicular magnetic anisotropy, where accumulated spins from the spin Hall effect in an adjacent heavy metal layer are responsible for driving the domain wall motion. It is found that that the sign and magnitude of the domain wall velocity in the uniform flow regime can be tuned significantly by the in-plane magnetic anisotropy. These effects are sensitive to the ratio of the adiabatic and non-adiabatic spin transfer torque parameters and are robust in the presence of pinning and thermal fluctuations.

  19. Starting solutions for oscillating motions of an Oldroyd-B fluid over a plane wall

    NASA Astrophysics Data System (ADS)

    Anjum, Asia; Ayub, Muhammad; Khan, Masood

    2012-01-01

    In this paper, we establish the starting solutions for oscillating motions of an Oldroyd-B fluid between two side walls perpendicular to a plane wall. The expressions for the velocity field and the associated tangential stress at the bottom wall are obtained, presented under integral and series form. These satisfy all imposed initial and boundary conditions. The obtained solutions are graphically analyzed for the variations of interesting flow parameters. In the absence of side walls, all solutions that have been obtained reduce to those corresponding to the motion over an infinite plate. Moreover, the obtained solutions can be specialized to give similar solutions for Maxwell, second grade and Newtonian fluids performing the same motions.

  20. Synchronous precessional motion of multiple domain walls in a ferromagnetic nanowire by perpendicular field pulses

    PubMed Central

    Kim, June-Seo; Mawass, Mohamad-Assaad; Bisig, André; Krüger, Benjamin; Reeve, Robert M.; Schulz, Tomek; Büttner, Felix; Yoon, Jungbum; You, Chun-Yeol; Weigand, Markus; Stoll, Hermann; Schütz, Gisela; Swagten, Henk J. M.; Koopmans, Bert; Eisebitt, Stefan; Kläui, Mathias

    2014-01-01

    Magnetic storage and logic devices based on magnetic domain wall motion rely on the precise and synchronous displacement of multiple domain walls. The conventional approach using magnetic fields does not allow for the synchronous motion of multiple domains. As an alternative method, synchronous current-induced domain wall motion was studied, but the required high-current densities prevent widespread use in devices. Here we demonstrate a radically different approach: we use out-of-plane magnetic field pulses to move in-plane domains, thus combining field-induced magnetization dynamics with the ability to move neighbouring domain walls in the same direction. Micromagnetic simulations suggest that synchronous permanent displacement of multiple magnetic walls can be achieved by using transverse domain walls with identical chirality combined with regular pinning sites and an asymmetric pulse. By performing scanning transmission X-ray microscopy, we are able to experimentally demonstrate in-plane magnetized domain wall motion due to out-of-plane magnetic field pulses. PMID:24663150

  1. Management of Respiratory Motion in Extracorporeal High-Intensity Focused Ultrasound Treatment in Upper Abdominal Organs: Current Status and Perspectives

    SciTech Connect

    Muller, A.; Petrusca, L.; Auboiroux, V.; Valette, P. J.; Salomir, R.; Cotton, F.

    2013-12-15

    Extracorporeal high-intensity focused ultrasound (HIFU) is a minimally invasive therapy considered with increased interest for the ablation of small tumors in deeply located organs while sparing surrounding critical tissues. A multitude of preclinical and clinical studies have showed the feasibility of the method; however, concurrently they showed several obstacles, among which the management of respiratory motion of abdominal organs is at the forefront. The aim of this review is to describe the different methods that have been proposed for managing respiratory motion and to identify their advantages and weaknesses. First, we specify the characteristics of respiratory motion for the liver, kidneys, and pancreas and the problems it causes during HIFU planning, treatment, and monitoring. Second, we make an inventory of the preclinical and clinical approaches used to overcome the problem of organ motion. Third, we analyze their respective benefits and drawbacks to identify the remaining physical, technological, and clinical challenges. We thereby consider the outlook of motion compensation techniques and those that would be the most suitable for clinical use, particularly under magnetic resonance thermometry monitoring.

  2. Direct Imaging of Thermally Driven Domain Wall Motion in Magnetic Insulators

    NASA Astrophysics Data System (ADS)

    Jiang, Wanjun; Upadhyaya, Pramey; Fan, Yabin; Zhao, Jing; Wang, Minsheng; Chang, Li-Te; Lang, Murong; Wong, Kin L.; Lewis, Mark; Lin, Yen-Ting; Tang, Jianshi; Cherepov, Sergiy; Zhou, Xuezhi; Tserkovnyak, Yaroslav; Schwartz, Robert N.; Wang, Kang L.

    2013-04-01

    Thermally induced domain wall motion in a magnetic insulator was observed using spatiotemporally resolved polar magneto-optical Kerr effect microscopy. The following results were found: (i) the domain wall moves towards hot regime; (ii) a threshold temperature gradient (5K/mm), i.e., a minimal temperature gradient required to induce domain wall motion; (iii) a finite domain wall velocity outside of the region with a temperature gradient, slowly decreasing as a function of distance, which is interpreted to result from the penetration of a magnonic current into the constant temperature region; and (iv) a linear dependence of the average domain wall velocity on temperature gradient, beyond a threshold thermal bias. Our observations can be qualitatively explained using a magnonic spin transfer torque mechanism, which suggests the utility of magnonic spin transfer torque for controlling magnetization dynamics.

  3. Harmonic amplitude distribution in a wideband ultrasonic wavefront after propagation through human abdominal wall and breast specimens.

    PubMed

    Liu, D L; Waag, R C

    1997-02-01

    The amplitude characteristics of ultrasonic wavefront distortion produced by transmission through the abdominal wall and breast is described. Ultrasonic pulses were recorded in a two-dimensional aperture after transmission through specimens of abdominal wall or breast. After the pulse arrival times were corrected for geometric path differences, the pulses were temporally Fourier transformed and two-dimensional maps of harmonic amplitudes in the measurement aperture were computed. The results indicate that, as the temporal frequency increases, the fluctuation in harmonic amplitudes increases but the spatial scale of the fluctuation decreases. The normalized second-order and third-order moments of the amplitude distribution also increase with temporal frequency. The wide range variation of these distribution characteristics could not be covered by the Rayleigh, Rician, or K-distribution because of their limited flexibility. However, the Weibull distribution and especially the generalized K-distribution provide better fits to the data. In the fit of the generalized K-distribution, a decrease of its parameter alpha with increasing temporal frequency was observed, as predicted by analysis based on a phase screen model. PMID:9035403

  4. Radionuclide ventriculography: evaluation of automated and visual methods for regional wall motion analysis

    SciTech Connect

    Steckley, R.A.; Kronenberg, M.W.; Born, M.L.; Rhea, T.C.; Bateman, J.E.; Rollo, F.D.; Friesinger, G.C.

    1982-01-01

    Regional wall motion (RWM) abnormalities are sensitive indicators of left ventricular (LV) dysfunction, but quantitation of RWM with gated radionuclide ventriculography (RVG) has been limited, particularly in the left anterior oblique (LAO) projection. Regional LV performance was studied in 18 patients undergoing LAO RVG immediately prior to contrast ventriculography (CVG). Wall motion was analyzed by semiautomated and visual methods using several coordinate systems. For semiautomated methods, RVG and CVG wall motion were closely related in the two 90 degrees polar sectors at the apex and posterior wall (r . .85) and in the five 45 degrees polar sectors from midseptum through posterior wall (r . .82). The basal sectors on RVG had weak relationship to CVG, due to adjacent vascular structures. Semiautomated and visual grades for polar sectors on both CVG and RVG were closely related (r . .88- .94). Measured regional wall motion on LAO RVG compared favorably with near-simultaneous CVG in nonoverlapping portions of the LV and allowed objective quantitation of regional LV performance.

  5. Radionuclide ventriculography: evaluation of automated and visual methods for regional wall motion analysis

    SciTech Connect

    Steckley, R.A.; Kronenberg, M.W.; Born, M.L.; Rhea, T.C.; Bateman, J.E.; Rollo, F.D.; Friesinger, G.C.

    1982-01-01

    Regional wall motion (RWM) abnormalities are sensitive indicators of left ventricular (LV) dysfunction, but quantitation of RWM with gated radionuclide ventriculography (RVG) has been limited, particularly in the left anterior oblique (LAO) projection. Regional LV performance was studied in 18 patients undergoing LAO RVG immediately prior to contrast ventriculography (CVG). Wall motion was analyzed by semiautomated and visual methods using several coordinate systems. For semiautomated methods, RVG and CVG wall motion were closely related in the two 90/sup 0/ polar sectors at the apex and posterior wall r = .850 and in the five 45/sup 0/ polar sectors from midseptum through posterior wall (r = .82). The basal sectors on RVG had weak relationships to CVG, due to adjacent vascular structures. Semiautomated and visual grades for polar sectors on both CVG and RVG were closely related (r = .88-.94). Measured regional wall motion on LAO RVG compared favorably with near-simultaneous CVG in nonoverlapping portions of the LV and allowed objective quantitation of regional LV performance.

  6. Konno-Mead analysis of ribcage-abdominal motion during successful and unsuccessful trials of weaning from mechanical ventilation.

    PubMed

    Tobin, M J; Guenther, S M; Perez, W; Lodato, R F; Mador, M J; Allen, S J; Dantzker, D R

    1987-06-01

    Respiratory muscle fatigue is considered a common cause of weaning failure but its detection is hampered by the lack of a satisfactory diagnostic test. Abdominal paradox has been proposed as a valuable clinical index of fatigue and thus its presence may lead to curtailment of weaning trials. However, sensitivity and specificity of this sign as a predictor of weaning outcome is unknown. We hypothesize that abnormal ribcage-abdominal (RC-Ab) motion is a common finding in the early stages of weaning and its presence does not inevitably imply an unsuccessful weaning outcome. We tested this hypothesis in patients undergoing a weaning trial: one group had a successful weaning outcome and were extubated (n = 10) and the other group failed the trial (n = 7). Normal RC-Ab motion was separately characterized in 17 healthy subjects. Employing a calibrated respiratory inductive plethysmograph, quantitative assessment of asynchrony and paradox was obtained by computing several indices from series of breaths at fixed time periods using the Konno-Mead method of analysis. During the weaning trial, both groups of patients displayed significant increases in asynchrony and Ab paradox compared to normal values. As a group, patients who failed the trial displayed significantly greater asynchrony and paradox of the RC and Ab than patients with a successful outcome. However, there was considerable overlap between the individual patients in the 2 study groups.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2954499

  7. Comparison of Current and Field Driven Domain Wall Motion in Beaded Permalloy Nanowires

    NASA Astrophysics Data System (ADS)

    Lage, Enno; Dutta, Sumit; Ross, Caroline A.

    2015-03-01

    Domain wall based devices are promising candidates for non-volatile memory devices with no static power consumption. A common approach is the use of (field assisted) current driven domain wall motion in magnetic nanowires. In such systems local variations in linewidth act as obstacles for propagating domain walls. In this study we compare simulated field driven and current driven domain wall motion in permalloy nanowires with anti-notches. The simulations were obtained using the Object Oriented MicroMagnetics Framework (OOMMF). The wires with a constant thickness of 8 nm exhibit linewidths ranging from 40 nm to 300 nm. Circular shaped anti-notches extend the linewidth locally by 10% to 30% and raise information about the domain wall propagation in such beaded nanowires. The results are interpreted in terms of the observed propagation behavior and summarized in maps indicating ranges of different ability to overcome the pinning caused by anti-notches of different sizes. Furthermore, regimes of favored domain wall type (transverse walls or vortex walls) and complex propagation effects like walker breakdown behavior or dynamic change between domain wall structures are identified The authors thank the German Academic Exchange Service (DAAD) for funding.

  8. Extensive Abdominal Wall Incisional Heterotopic Ossification Reconstructed with Component Separation and Strattice Inlay

    PubMed Central

    Suleiman, Nergis Nina

    2016-01-01

    Summary: Symptomatic heterotopic ossification of abdominal surgical incisions is a rare occurrence. We present a 67-year-old man with severe discomfort caused by heterotopic ossification extending from the xiphoid to the umbilicus. The patient underwent an abdominal aortic aneurysm repair 3 years before our treatment. A 13 × 3.5 cm ossified lesion was excised. The resulting midline defect was closed using component separation and inlay Strattice. Tension-free midline adaptation of the recti muscles was achieved. A computed tomography scan of the abdomen 6 months after the surgery showed no recurrence or hernias. Heterotopic ossification in symptomatic patients has previously been treated with excision and primary closure. We believe that tension-free repair is important to prevent recurrence. Acellular dermal matrix may add to this effect and also compartmentalize the process. PMID:27536495

  9. Extensive Abdominal Wall Incisional Heterotopic Ossification Reconstructed with Component Separation and Strattice Inlay.

    PubMed

    Suleiman, Nergis Nina; Sandberg, Lars Johan Marcus

    2016-07-01

    Symptomatic heterotopic ossification of abdominal surgical incisions is a rare occurrence. We present a 67-year-old man with severe discomfort caused by heterotopic ossification extending from the xiphoid to the umbilicus. The patient underwent an abdominal aortic aneurysm repair 3 years before our treatment. A 13 × 3.5 cm ossified lesion was excised. The resulting midline defect was closed using component separation and inlay Strattice. Tension-free midline adaptation of the recti muscles was achieved. A computed tomography scan of the abdomen 6 months after the surgery showed no recurrence or hernias. Heterotopic ossification in symptomatic patients has previously been treated with excision and primary closure. We believe that tension-free repair is important to prevent recurrence. Acellular dermal matrix may add to this effect and also compartmentalize the process. PMID:27536495

  10. Fast Magnetic Domain-Wall Motion in a Ring-Shaped Nanowire Driven by a Voltage.

    PubMed

    Hu, Jia-Mian; Yang, Tiannan; Momeni, Kasra; Cheng, Xiaoxing; Chen, Lei; Lei, Shiming; Zhang, Shujun; Trolier-McKinstry, Susan; Gopalan, Venkatraman; Carman, Gregory P; Nan, Ce-Wen; Chen, Long-Qing

    2016-04-13

    Magnetic domain-wall motion driven by a voltage dissipates much less heat than by a current, but none of the existing reports have achieved speeds exceeding 100 m/s. Here phase-field and finite-element simulations were combined to study the dynamics of strain-mediated voltage-driven magnetic domain-wall motion in curved nanowires. Using a ring-shaped, rough-edged magnetic nanowire on top of a piezoelectric disk, we demonstrate a fast voltage-driven magnetic domain-wall motion with average velocity up to 550 m/s, which is comparable to current-driven wall velocity. An analytical theory is derived to describe the strain dependence of average magnetic domain-wall velocity. Moreover, one 180° domain-wall cycle around the ring dissipates an ultrasmall amount of heat, as small as 0.2 fJ, approximately 3 orders of magnitude smaller than those in current-driven cases. These findings suggest a new route toward developing high-speed, low-power-dissipation domain-wall spintronics. PMID:27002341

  11. The quasi-static failure properties of the abdominal aortic aneurysm wall estimated by a mixed experimental-numerical approach.

    PubMed

    Forsell, Caroline; Swedenborg, Jesper; Roy, Joy; Gasser, T Christian

    2013-07-01

    Assessing the risk for abdominal aortic aneurysm (AAA) rupture is critical in the management of aneurysm patients and an individual assessment is possible with the biomechanical rupture risk assessment. Such an assessment could potentially be improved by a constitutive AAA wall model that accounts for irreversible damage-related deformations. Because of that the present study estimated the elastic and inelastic properties of the AAA wall through a mixed experimental-numerical approach. Specifically, finite element (FE) models of bone-shaped tensile specimens were used to merge data from failure testing of the AAA wall with their measured collagen orientation distribution. A histo-mechanical constitutive model for collagen fibers was employed, where plastic fibril sliding determined not only remaining deformations but also weakening of the fiber. The developed FE models were able to replicate the experimentally recorded load-displacement property of all 16 AAA wall specimens that were investigated in the study. Tensile testing in longitudinal direction of the AAA defined a Cauchy strength of 569(SD 411) kPa that was reached at a stretch of 1.436(SD 0.118). The stiffness and strength of specimens decreased with the wall thickness and were elevated (p = 0.018; p = 0.030) in patients with chronic obstructive pulmonary disease (COPD). Smoking affected the tissue parameters that were related to the irreversible deformation response, and no correlation with gender and age was found. The observed effects on the biomechanical properties of the AAA wall could have long-term consequences for the management of aneurysm patients, i.e., specifically they might influence future AAA rupture risk assessments. However, in order to design appropriate clinical validation studies our findings should firstly be verified in a larger patient cohort. PMID:23263935

  12. Dual registration of abdominal motion for motility assessment in free-breathing data sets acquired using dynamic MRI

    NASA Astrophysics Data System (ADS)

    Menys, A.; Hamy, V.; Makanyanga, J.; Hoad, C.; Gowland, P.; Odille, F.; Taylor, S. A.; Atkinson, D.

    2014-08-01

    At present, registration-based quantification of bowel motility from dynamic MRI is limited to breath-hold studies. Here we validate a dual-registration technique robust to respiratory motion for the assessment of small bowel and colonic motility. Small bowel datasets were acquired in breath-hold and free-breathing in 20 healthy individuals. A pre-processing step using an iterative registration of the low rank component of the data was applied to remove respiratory motion from the free breathing data. Motility was then quantified with an existing optic-flow (OF) based registration technique to form a dual-stage approach, termed Dual Registration of Abdominal Motion (DRAM). The benefit of respiratory motion correction was assessed by (1) assessing the fidelity of automatically propagated segmental regions of interest (ROIs) in the small bowel and colon and (2) comparing parametric motility maps to a breath-hold ground truth. DRAM demonstrated an improved ability to propagate ROIs through free-breathing small bowel and colonic motility data, with median error decreased by 90% and 55%, respectively. Comparison between global parametric maps showed high concordance between breath-hold data and free-breathing DRAM. Quantification of segmental and global motility in dynamic MR data is more accurate and robust to respiration when using the DRAM approach.

  13. Avoiding Complications in Abdominal Wall Surgery: A Mathematical Model to Predict the Course of the Motor Innervation of the Rectus Abdominis.

    PubMed

    Tessone, Ariel; Nava, Maurizio; Blondeel, Phillip; Spano, Andrea

    2016-02-01

    Ever since its introduction, the transverse rectus abdominis myocutaneous flap has become the mainstay of autologous breast reconstruction. However, concerns regarding donor site morbidity due to the breach of abdominal wall musculature integrity soon followed. Muscle-sparing techniques, eventually eliminating the muscle from the flap all-together with the deep inferior epigastric artery perforator flap, did not eliminate the problem of abdominal wall weakness. This led to the conclusion that motor innervation might be at fault. Studies have shown that even in the presence of an intact rectus abdominis muscle, and an intact anterior rectus sheath, denervation of the rectus abdominis muscle results in significant abdominal wall weakness leading to superior and inferior abdominal bulges, and abdominal herniation. Our aim was to establish a mathematical model to predict the location of the motor innervation to the rectus abdominis muscle, and thus provide surgeons with a tool that will allow them to reduce abdominal morbidity during deep inferior epigastric artery perforator and free muscle-sparing transverse rectus abdominis myocutaneous surgery. We dissected 42 cadaveric hemiabdomens and mapped the course of the thoracolumbar nerves. We then standardized and analyzed our findings and presented them as a relative map which can be adjusted to body type and dimensions. Our dissections show that the motor innervation is closely related to the lateral vascular supply. Thus, when possible, we support the preferred utilization of the medial vascular supply, and the preservation of the lateral supply and motor innervation. PMID:26756600

  14. Coupled Néel domain wall motion in sandwiched perpendicular magnetic anisotropy nanowires

    PubMed Central

    Purnama, I.; Kerk, I. S.; Lim, G. J.; Lew, W. S.

    2015-01-01

    The operating performance of a domain wall-based magnetic device relies on the controlled motion of the domain walls within the ferromagnetic nanowires. Here, we report on the dynamics of coupled Néel domain wall in perpendicular magnetic anisotropy (PMA) nanowires via micromagnetic simulations. The coupled Néel domain wall is obtained in a sandwich structure, where two PMA nanowires that are separated by an insulating layer are stacked vertically. Under the application of high current density, we found that the Walker breakdown phenomenon is suppressed in the sandwich structure. Consequently, the coupled Néel domain wall of the sandwich structure is able to move faster as compared to individual domain walls in a single PMA nanowire. PMID:25736593

  15. Domain wall motion in sub-100 nm magnetic wire

    NASA Astrophysics Data System (ADS)

    Siddiqui, Saima; Dutta, Sumit; Currivan, Jean Anne; Ross, Caroline; Baldo, Marc

    2015-03-01

    Nonvolatile memory devices such as racetrack memory rely on the manipulation of domain wall (DW) in magnetic nanowires, and scaling of these devices requires an understanding of domain wall behavior as a function of the wire width. Due to the increased importance of edge roughness and magnetostatic interaction, DW pinning increases dramatically as the wire dimensions decrease and stochastic behavior is expected depending on the distribution of pinning sites. We report on the field driven DW statistics in sub-100 nm wide nanowires made from Co films with very small edge roughness. The nanowires were patterned in the form of a set of concentric rings of 10 μm diameter. Two different width nanowires with two different spacings have been studied. The rings were first saturated in plane to produce onion states and then the DWs were translated in the wires using an orthogonal in-plane field. The position of the DWs in the nanowires was determined with magnetic force microscopy. From the positions of the DWs in the nanowires, the strength of the extrinsic pinning sites was identified and they follow two different distributions in two different types of nanowire rings. For the closely spaced wires, magnetostatic interactions led to correlated movement of DWs in neighboring wires. The implications of DW pinning and interaction in nanoscale DW devices will be discussed.

  16. Current-induced 360° domain wall motion with Dzyaloshinskii–Moriya interaction

    NASA Astrophysics Data System (ADS)

    Jin, Chendong; Zhang, Senfu; Zhu, Qiyuan; Liu, Xianyin; Chen, Shujun; Song, Chengkun; Wang, Jianbo; Liu, Qingfang

    2016-05-01

    By micromagnetic simulation, we investigated the effect of the Dzyaloshinskii–Moriya interaction (DMI) on the static and dynamic characteristics of a 360° domain wall. Simulation results show that both the energy and the size of a 360° domain wall decrease with the increase of DMI intensity. In the presence of DMI, the stable motion of a 360° domain wall can be either along the  +x direction or  ‑x direction depending on the sign of the DMI. For stable motion, the maximum velocity of a 360° domain wall is 19.87% larger than that without the DMI. Increasing the current density beyond the Walker threshold, conversion between the 360° domain wall state and the vortex state was observed. Further increasing the current density, the proliferation of 360° domain walls becomes possible. Moreover, the 360° domain wall becomes more flexible and easier to pass a notch by considering the DMI. These findings may offer guidance for the development of 360° domain wall-based racetrack memories.

  17. Electric field driven magnetic domain wall motion in ferromagnetic-ferroelectric heterostructures

    SciTech Connect

    Van de Wiele, Ben; Laurson, Lasse; Franke, Kévin J. A.; Dijken, Sebastiaan van

    2014-01-06

    We investigate magnetic domain wall (MDW) dynamics induced by applied electric fields in ferromagnetic-ferroelectric thin-film heterostructures. In contrast to conventional driving mechanisms where MDW motion is induced directly by magnetic fields or electric currents, MDW motion arises here as a result of strong pinning of MDWs onto ferroelectric domain walls (FDWs) via local strain coupling. By performing extensive micromagnetic simulations, we find several dynamical regimes, including instabilities such as spin wave emission and complex transformations of the MDW structure. In all cases, the time-averaged MDW velocity equals that of the FDW, indicating the absence of Walker breakdown.

  18. Internal friction due to domain-wall motion in martensitically transformed A15 compounds

    SciTech Connect

    Snead, C.L. Jr.; Welch, D.O.

    1985-01-01

    A lattice instability in A15 materials in some cases leads to a cubic-to-tetragonal martensitic transformation at low temperatures. The transformed material orients in lamellae with c axes alternately aligned along the <100> directions producing domain walls between the lamellae. An internal-friction (delta) feature below T/sub m/ is attributed to stress-induced domain-wall motion. The magnitude of the friction increases as temperature is lowered below T/sub m/ as (1-c/a) increases, and behaves as (1-c/a)/sup 2/ from T/sub m/ down to the superconducting critical temperature where the increasing tetragonality is inhibited. The effect of strain in the lattice is to decrease the domain-wall internal friction, but not affect T/sub m/. Neutron-induced disorder and the addition of some third-elements in alloying decrease both delta and T/sub m/, with some elements reducing only the former. Less than 1 at. % H is seen to completely suppress both delta and T/sub m. Martensitically transformed V/sub 2/Zr demonstrates low-temperature internal-friction and modulus behavior consists with easy ..beta../m wall motion relative to the easy m/m motion of the A15's. For the V/sub 2/Zr, a peak in delta is observed, qualitatively in agreement with expected ..beta../m wall motion.

  19. Three dimensional quantification of left ventricular wall motion by ECG-gated blood pool emission tomography

    SciTech Connect

    Underwood, S.R.; Walton, S.; Laming, P.J.; Jarritt, P.H.; Ell, P.J.; Emanuel, R.W.; Swanton, R.H.

    1985-05-01

    ECG-gated blood pool emission tomography is a relatively new technique, and this study establishes a simple method for displaying the three dimensional data obtained, determines a normal range for ejection fraction in all regions of the left ventricle, and compares wall motion in abnormal subjects with that determined by X-ray contrast ventriculography. The short axis sections dividing the ventricle in slices from apex to base, were used to calculate ejection fraction for all parts of the ventricle and the results were plotted on a single colour coded circular image. The apex was represented in the centre, the base around the circumference, and all other parts of the ventricle were represented in between. The image was divided into 15 segments, and normal segmental ejection fraction was defined as within two standard deviations of the mean in a group of 10 normal subjects. In 25 subjects with coronary artery disease, motion of the anterior, apical, and inferior walls agreed in every case with the right anterior oblique contrast ventriculogram, but in 12 of these, the three dimensional ejection fraction image showed abnormal septal motion, and in a further 3, abnormal lateral wall motion in addition. In the 12 subjects there was disease of the left anterior descending coronary artery, and in the further 3 there was left circumflex disease. ECG-gated blood pool emission tomography thus provides an accurate quantitative assessment of left ventricular wall motion in three dimensions, and has significant advantages over conventional planar techniques.

  20. Pitching-motion-activated flapping foil near solid walls for power extraction: A numerical investigation

    NASA Astrophysics Data System (ADS)

    Wu, J.; Qiu, Y. L.; Shu, C.; Zhao, N.

    2014-08-01

    A numerical investigation on the power extraction of a pitching-motion-activated flapping foil near solid walls is performed by using an immersed boundary-lattice Boltzmann method in this study. The flapping motions of the foil include a forced pitching component and an induced plunging component. The foil is placed either near a solid wall or between two parallel plane walls. Compared to previous work on the flapping foil for power extraction, the effect of the walls is first considered in this work. At a Reynolds number of 1100 and with the position of the foil pitching axis at third chord, the influences of the mechanical parameters (such as damping coefficient and spring constant) of the foil, the amplitude and frequency of the pitching motion and the clearance between the foil pitching axis and the wall on the power extraction performance of the flapping foil are systematically evaluated. Compared to the situation of free stream, the power extraction performance of the foil near the wall is improved. For given amplitude and frequency, as the clearance decreases the net power extraction efficiency improves. Moreover, as the foil is placed near one wall, there is a transverse shift to the plunging motion that consequently weakens the improvement of net power extraction efficiency. In contrast, the shift can be significantly eliminated as the foil is placed between two walls, which can further improve the net power extraction efficiency. In addition, it is found that the efficiency improvement is essentially from the increased power extraction, which is due to the generation of high lift force.

  1. Nucleation, imaging, and motion of magnetic domain walls in cylindrical nanowires

    NASA Astrophysics Data System (ADS)

    Da, S., Col; Jamet, S.; StaÅo, M.; Trapp, B.; Le Denmat, S.; Cagnon, L.; Toussaint, J. C.; Fruchart, O.

    2016-08-01

    We report several procedures for the robust nucleation of magnetic domain walls in cylindrical permalloy nanowires. Specific features of the magnetic force microscopy (MFM) contrast of such wires are discussed, to avoid the misinterpretation of the magnetization states. The domain walls moved under quasistatic magnetic fields in the range 0.1-10 mT, as evidenced by MFM at remanence at different stages of their motion.

  2. Compliant wall surface motion and its effect on the structure of a turbulent boundary layer

    NASA Technical Reports Server (NTRS)

    Ash, R. L.; Balasubramanian, R.; Bushnell, D. M.; Weinstein, L. M.

    1977-01-01

    The status of the continuing compliant wall drag reduction research at NASA-Langley Research Center is discussed. Preliminary surface motion calculations are reported along with compliant surface design concepts and their numerical models. A compliant drag reduction theory based on stabilizing the turbulent substructure is proposed and previous experiments have been examined relative to that theory. Results of recent low speed compliant surface experiments have been reported which include initial attempts to measure local compliant surface motion.

  3. Vortex motion in wall-bounded viscous flow

    NASA Technical Reports Server (NTRS)

    Gatski, T. B.

    1985-01-01

    A factor of general interest in a broad class of wall-bounded flows is the dynamic evolution of vortical structures through the flow. The structures are three-dimensional, and an overall mathematical description of such entities has not yet been formulated. One of the objectives of the present investigation is concerned with the establishment of a framework, based on first principles, which may form a basis for more detailed analytical studies. Another aim is related to the establishment of boundary and initial conditions in numerical experiments. The mathematical framework employed involves the method of matched asymptotic expansions, and an inner solution field is constructed which consists of a two-dimensional vortical structure. The outer solution field is taken to be an otherwise undisturbed laminar two-dimensional parallel or self-similar viscous flowfield.

  4. Reduction of aneurysm pressure and wall stress after endovascular repair of abdominal aortic aneurysm in a canine model.

    PubMed

    Marston, W A; Criado, E; Baird, C A; Keagy, B A

    1996-03-01

    A canine model was designed to evaluate the changes in abdominal aortic aneurysm (AAA) pressure and wall stress after endovascular repair. Eight canines underwent laparotomy and creation of an AAA. The aneurysm was then excluded with a transluminally placed endovascular graft (TPEG) inserted through the right femoral artery and deployed across the AAA to exclude the infrarenal aortic branches from aortic perfusion. Blood pressure and flow data were recorded for 6 hours. The AAA blood pressure decreased from 135 +/- 9.3 mm Hg before exclusion to 45 +/- 17.6 mm Hg at 10 minutes after exclusion (p < 0.001). At 6 hours, AAA blood pressure had declined further to 26 +/- 12.5 mm Hg. Blood flow in the excluded iliac artery decreased from a baseline of 242 +/- 58 ml/min to 41 +/- 29 ml/min 10 minutes after TPEG placement (p < 0.001). At 6 hours, flow was reduced to 12 +/- 3.5 ml/min (p < 0.05 compared with that at 10 minutes). Aortic wall stress was significantly reduced by TPEG placement but was only slightly lower than baseline aortic wall stress before AAA creation. The lumbar arteries were patent with retrograde flow in all cases and were found to be the major contributors to postexclusion aneurysm pressure. Endovascular AAA exclusion results in an immediate decrease in blood pressure and wall stress within the excluded aneurysm, but the aneurysm remains perfused by retrograde flow through the lumbar arteries, which resulted in near-baseline levels of aneurysm wall stress in this canine model. Embolization of patient lumbar vessels at prosthesis placement may further reduce the risk of late rupture. PMID:8733869

  5. Curvature and torsion effects in spin-current driven domain wall motion

    NASA Astrophysics Data System (ADS)

    Yershov, Kostiantyn V.; Kravchuk, Volodymyr P.; Sheka, Denis D.; Gaididei, Yuri

    2016-03-01

    The domain wall motion along a helix-shaped nanowire is studied for the case of spin-current driving via the Zhang-Li mechanism. The analysis is based on the collective variable approach. Two effects are ascertained: (i) the curvature results in the appearance of the Walker limit for a uniaxial wire, and (ii) the torsion results in effective shift of the nonadiabatic spin torque parameter β . The latter effect changes considerably the domain wall velocity and can result in negative domain wall mobility. This effect can be also used for an experimental determination of the nonadiabatic parameter β and damping coefficient α .

  6. Novel superhydrophilic poly(l-lactic acid-co-ε-caprolactone)/fibrinogen electrospun patch for rat abdominal wall reconstruction.

    PubMed

    Liu, Zhang; Li, Shaojie; Su, Ling; Sun, Kang; Wu, Xujun; Wu, Feng; Huang, Weihong; Yang, Li; Tang, Jianxiong; He, Hongbing

    2015-08-01

    A novel superhydrophilic hybrid scaffold was created by electrospinning a mixture of poly(l-lactic acid-co-ε-caprolactone) and formulated fibrinogen. The hybrid scaffolds possess the combined benefits of each individual component, such as moderate mechanical strength and excellent biocompatibility. In vitro studies also revealed that endothelial cells seeded on the hybrid scaffolds achieved a relatively high level of cell attachment after three days of culture and a significant increase in the proliferation rate after seven days of culture, compared with pure fibrinogen or poly(l-lactic acid-co-ε-caprolactone) scaffolds. A comparative study of hybrid and pure poly(l-lactic acid-co-ε-caprolactone) patches was performed in an abdominal wall defect model in rats. In both groups, implants degraded by six months, but muscle reconstruction was only observed in the hybrid patch group. PMID:25791683

  7. Experimentally tunable chiral spin transfer torque in domain wall motion

    NASA Astrophysics Data System (ADS)

    Ryu, Kwang-Su; Yang, See-Hun; Parkin, Stuart

    2016-05-01

    Domain walls (DWs) can be moved very efficiently with nanosecond long current pulses in perpendicularly magnetized Co/Ni/Co nanowires formed with platinum under- and over-layers due to a chiral spin torque mechanism. In these structures the DWs exhibit a chiral Néel structure that has been proposed is set by a Dyzaloshinskii–Moriya exchange interaction (DMI) arising from the Pt/Co and Co/Pt interfaces. The strength of this interaction can be measured from the longitudinal field dependence of the current induced DW velocity. We show, thereby, that the magnitude and sign of the DMI is strongly dependent and monotonically changes as small changes in the thicknesses of the Co layers are made. However, due to the chiral nature of the DMI we show that the magnitude and sign of the DMI is determined by the difference between the respective DMI at the upper and lower interfaces, which compensate each other. Thus, we find that the DMI increases as the lower Co thickness is increased but decreases as the upper Co thickness is increased, changing sign in both cases.

  8. Modulated Magnetic Nanowires for Controlling Domain Wall Motion: Toward 3D Magnetic Memories.

    PubMed

    Ivanov, Yurii P; Chuvilin, Andrey; Lopatin, Sergei; Kosel, Jurgen

    2016-05-24

    Cylindrical magnetic nanowires are attractive materials for next generation data storage devices owing to the theoretically achievable high domain wall velocity and their efficient fabrication in highly dense arrays. In order to obtain control over domain wall motion, reliable and well-defined pinning sites are required. Here, we show that modulated nanowires consisting of alternating nickel and cobalt sections facilitate efficient domain wall pinning at the interfaces of those sections. By combining electron holography with micromagnetic simulations, the pinning effect can be explained by the interaction of the stray fields generated at the interface and the domain wall. Utilizing a modified differential phase contrast imaging, we visualized the pinned domain wall with a high resolution, revealing its three-dimensional vortex structure with the previously predicted Bloch point at its center. These findings suggest the potential of modulated nanowires for the development of high-density, three-dimensional data storage devices. PMID:27138460

  9. Behaviour of a New Composite Mesh for the Repair of Full-Thickness Abdominal Wall Defects in a Rabbit Model

    PubMed Central

    Pascual, Gemma; Sotomayor, Sandra; Rodríguez, Marta; Bayon, Yves; Bellón, Juan M.

    2013-01-01

    Introduction Composite biomaterials designed for the repair of abdominal wall defects are composed of a mesh component and a laminar barrier in contact with the visceral peritoneum. This study assesses the behaviour of a new composite mesh by comparing it with two latest-generation composites currently used in clinical practice. Methods Defects (7x5cm) created in the anterior abdominal wall of New Zealand White rabbits were repaired using a polypropylene mesh and the composites: PhysiomeshTM; VentralightTM and a new composite mesh with a three-dimensional macroporous polyester structure and an oxidized collagen/chitosan barrier. Animals were sacrificed on days 14 and 90 postimplant. Specimens were processed to determine host tissue incorporation, gene/protein expression of neo-collagens (RT-PCR/immunofluorescence), macrophage response (RAM-11-immunolabelling) and biomechanical resistance. On postoperative days 7/14, each animal was examined laparoscopically to quantify adhesions between the visceral peritoneum and implant. Results The new composite mesh showed the lowest incidence of seroma in the short term. At each time point, the mesh surface covered with adhesions was greater in controls than composites. By day 14, the implants were fully infiltrated by a loose connective tissue that became denser over time. At 90 days, the peritoneal mesh surface was lined with a stable mesothelium. The new composite mesh induced more rapid tissue maturation than PhysiomeshTM, giving rise to a neoformed tissue containing more type I collagen. In VentralightTM the macrophage reaction was intense and significantly greater than the other composites at both follow-up times. Tensile strengths were similar for each biomaterial. Conclusions All composites showed optimal peritoneal behaviour, inducing good peritoneal regeneration and scarce postoperative adhesion formation. A greater foreign body reaction was observed for VentralightTM. All composites induced good collagen deposition

  10. Field-driven Domain Wall Motion in Ferromagnetic Nanowires with Bulk Dzyaloshinskii-Moriya Interaction.

    PubMed

    Zhuo, Fengjun; Sun, Z Z

    2016-01-01

    Field-driven domain wall (DW) motion in ferromagnetic nanowires with easy- and hard-axis anisotropies was studied theoretically and numerically in the presence of the bulk Dzyaloshinskii-Moriya interaction (DMI) based on the Landau-Lifshitz-Gilbert equation. We propose a new trial function and offer an exact solution for DW motion along a uniaxial nanowire driven by an external magnetic field. A new strategy was suggested to speed up DW motion in a uniaxial magnetic nanowire with large DMI parameters. In the presence of hard-axis anisotropy, we find that the breakdown field and velocity of DW motion was strongly affected by the strength and sign of the DMI parameter under external fields. This work may be useful for future magnetic information storage devices based on DW motion. PMID:27118064

  11. Field-driven domain wall motion in ferromagnetic nanowires with Dzyaloshinskii-Moriya interaction

    NASA Astrophysics Data System (ADS)

    Fengjun, Zhuo; Zhouzhou, Sun

    Field-driven domain-wall (DW) motion in ferromagnetic nanowires with easy- and hard-axis anisotropies was studied theoretically and numerically in the presence of the Dzyaloshinskii-Moriya interaction (DMI) based on the Landau-Lifshitz-Gilbert equation. We proposed a new trial function and found the exact solution for the DW motion along a uniaxial nanowire driven by an external magnetic field. A new strategy was suggested to speed up the DW motion in a uniaxial magnetic nanowire with large DMI parameters. In the presence of the hard-axis anisotropy, we found that the breakdown field and velocity of the DW motion was strongly affected by the strength and sign of the DMI parameter under external fields. The work may be useful for future magnetic information storage devices based on the DW motion.

  12. Field-driven Domain Wall Motion in Ferromagnetic Nanowires with Bulk Dzyaloshinskii-Moriya Interaction

    NASA Astrophysics Data System (ADS)

    Zhuo, Fengjun; Sun, Z. Z.

    2016-04-01

    Field-driven domain wall (DW) motion in ferromagnetic nanowires with easy- and hard-axis anisotropies was studied theoretically and numerically in the presence of the bulk Dzyaloshinskii-Moriya interaction (DMI) based on the Landau-Lifshitz-Gilbert equation. We propose a new trial function and offer an exact solution for DW motion along a uniaxial nanowire driven by an external magnetic field. A new strategy was suggested to speed up DW motion in a uniaxial magnetic nanowire with large DMI parameters. In the presence of hard-axis anisotropy, we find that the breakdown field and velocity of DW motion was strongly affected by the strength and sign of the DMI parameter under external fields. This work may be useful for future magnetic information storage devices based on DW motion.

  13. Field-driven Domain Wall Motion in Ferromagnetic Nanowires with Bulk Dzyaloshinskii-Moriya Interaction

    PubMed Central

    Zhuo, Fengjun; Sun, Z. Z.

    2016-01-01

    Field-driven domain wall (DW) motion in ferromagnetic nanowires with easy- and hard-axis anisotropies was studied theoretically and numerically in the presence of the bulk Dzyaloshinskii-Moriya interaction (DMI) based on the Landau-Lifshitz-Gilbert equation. We propose a new trial function and offer an exact solution for DW motion along a uniaxial nanowire driven by an external magnetic field. A new strategy was suggested to speed up DW motion in a uniaxial magnetic nanowire with large DMI parameters. In the presence of hard-axis anisotropy, we find that the breakdown field and velocity of DW motion was strongly affected by the strength and sign of the DMI parameter under external fields. This work may be useful for future magnetic information storage devices based on DW motion. PMID:27118064

  14. 3D analysis of the chest wall motion for monitoring late-onset Pompe disease patients.

    PubMed

    Meric, Henri; Falaize, Line; Pradon, Didier; Orlikowski, David; Prigent, Hélène; Lofaso, Frédéric

    2016-02-01

    Late-onset Pompe disease, for which enzyme replacement therapy is available, induces progressive diaphragmatic weakness. Monitoring diaphragmatic function is therefore crucial but is hindered by the need to insert esophageal and gastric probes. Vital capacity (VC), inspiratory capacity, maximal inspiratory pressure, and sniff nasal pressure are noninvasive measurements but reflect only global inspiratory-muscle function. Diaphragmatic function may be assessable noninvasively based on abdominal contribution to breathing and abdominal volume change during the VC maneuver (AVC-VC), obtained by 3-dimensional chest-wall analysis. In 11 patients, we assessed the relationships between the above-listed noninvasive variables and the invasively measured Gilbert index reflecting the diaphragmatic contribution to breathing (ratio of gastric pressure over transdiaphragmatic pressure swings during spontaneous breathing). Only abdominal contribution to breathing and AVC-VC correlated significantly with the Gilbert index (R = 0.977, P = 0.0001; and R = 0.944, P = 0.001 respectively). AVC-VC correlated significantly with transdiaphragmatic pressure swing during the sniff maneuver (R = 0.743, P = 0.0009) and with phrenic magnetic stimulation (R = 0.610, P = 0.046). Repeat testing 1 year later in the first 6 patients showed concordant changes in abdominal contribution to breathing, Gilbert index, and VC. Abdominal contribution to breathing and AVC-VC are reliable and noninvasive indices of diaphragmatic function in Pompe disease, and therefore hold promise as clinical monitoring tools. PMID:26711305

  15. Effects of impurity transport and melt layer motion to the tungsten wall erosion during anomaly events

    NASA Astrophysics Data System (ADS)

    Ibano, K.; Tsutsui, T.; Lang, T. L.; Togo, S.; Ogawa, Y.

    2015-08-01

    Developing designs of future fusion devices, safety and soundness of the rector at anomaly events must be ensured. A computational approach is being taken by developing a homegrown integrated reactor simulation code and analyzing a loss-of-cooling-gas-puff accident (LCGA). This code currently includes simple plasma, edge, and wall models. In this study, models for the tungsten transport and melt layer motion was added and used for the analysis. It was found that this accident results significant erosion of the wall while impurities from the wall would contribute the radiation cooling for the intense heat flux. However, these effects strongly depend on an uncertain parameter of the tungsten transport as well as the tungsten melt layer motion. Thus, parametric survey for these uncertain quantities were taken and discussed.

  16. New techniques for the assessment of regional left ventricular wall motion.

    PubMed

    Garcia-Fernandez, Miguel Angel; Bermejo, Javier; Perez-David, Esther; Lopez-Fernandez, Teresa; Ledesma, Maria Jesus; Caso, Pio; Malpica, Norberto; Santos, Andres; Moreno, Mar; Desco, Manuel

    2003-10-01

    The assessment of regional left ventricular (LV) function has been an important yet unresolved problem since the introduction of echocardiography as a diagnostic tool. Abnormal regional LV wall motion is an early finding in multiple cardiac pathologies and its diagnosis is of critical importance. In the last few years diagnostic procedures based on combined use of existing echocardiographic technologies were geared toward improving the accuracy of detection of baseline and/or induced regional wall motion abnormalities. One of the assumptions is that the combination of reduced LV wall thickening and reduced myocardial velocities can be used to accurately diagnose regional myocardial dysfunction. In this article we will discuss several new techniques for the quantification of regional LV function using Doppler echocardiography. PMID:14536016

  17. SU-E-T-538: Does Abdominal Compression Through Prone Patient Position Reduce Respiratory Motion in Lung Cancer Radiotherapy?

    SciTech Connect

    Catron, T; Rosu, M; Weiss, E

    2014-06-01

    Purpose: This study assesses the effect of physiological abdominal compression from prone positioning by comparing respiratory-induced tumor movements in supine and prone positions. Methods: 19 lung cancer patients underwent repeated supine and prone free-breathing 4DCT scans. The effect of patient position on motion magnitude was investigated for tumors, lymph nodes (9 cases), and subgroups of central (11 cases), peripheral (8 cases) and small peripheral tumors (5 cases), by evaluating the population average excursions, absolute and relative to a carina-point. Results: Absolute motion analysis: In prone, motion increased by ~20% for tumors and ~25% for lymph nodes. Central tumors moved more compared to peripheral tumors in both supine and prone (~22%, and ~4% respectively). Central tumors movement increased by ~12% in prone. For peripheral tumors the increase in prone position was ~25% (~40% and 29% changes on along RL and AP directions). Motion relative to carina-point analysis: Overall, tumor excursions relative to carina-point increased by ~17% in prone. Lymph node relative magnitudes were lower by ~4%. Likewise, the central tumors moved ~7% less in prone. The subgroup of peripheral tumors exhibited increased amplitudes by ~44%; the small peripheral tumors had even larger relative displacements in prone (~46%). Conclusion: Tumor and lymph node movement in the patient population from this study averaged to be higher in prone than in supine position. Results from carina analysis also suggest that peripheral tissues have more physiologic freedom of motility when placed in the prone position, regardless of size. From these observations we should continue to avoid prone positioning for all types of primary lung tumor, suggesting that patients should receive radiotherapy for primary lung cancer in supine position to minimize target tissue mobility during normal respiratory effort. Further investigation will include more patients with peripheral tumors to validate our

  18. SU-E-J-199: Evaluation of Motion Tracking Effects On Stereotactic Body Radiotherapy of Abdominal Targets

    SciTech Connect

    Monterroso, M; Dogan, N; Yang, Y

    2014-06-01

    Purpose: To evaluate the effects of respiratory motion on the delivered dose distribution of CyberKnife motion tracking-based stereotactic body radiotherapy (SBRT) of abdominal targets. Methods: Four patients (two pancreas and two liver, and all with 4DCT scans) were retrospectively evaluated. A plan (3D plan) using CyberKnife Synchrony was optimized on the end-exhale phase in the CyberKnife's MultiPlan treatment planning system (TPS), with 40Gy prescribed in 5 fractions. A 4D plan was then created following the 4D planning utility in the MultiPlan TPS, by recalculating dose from the 3D plan beams on all 4DCT phases, with the same prescribed isodose line. The other seven phases of the 4DCT were then deformably registered to the end-exhale phase for 4D dose summation. Doses to the target and organs at risk (OAR) were compared between 3D and 4D plans for each patient. The mean and maximum doses to duodenum, liver, spinal cord and kidneys, and doses to 5cc of duodenum, 700cc of liver, 0.25cc of spinal cord and 200cc of kidneys were used. Results: Target coverage in the 4D plans was about 1% higher for two patients and about 9% lower in the other two. OAR dose differences between 3D and 4D varied among structures, with doses as much as 8.26Gy lower or as much as 5.41Gy higher observed in the 4D plans. Conclusion: The delivered dose can be significantly different from the planned dose for both the target and OAR close to the target, which is caused by the relative geometry change while the beams chase the moving target. Studies will be performed on more patients in the future. The differences of motion tracking versus passive motion management with the use of internal target volumes will also be investigated.

  19. [The use of prosthetic materials placed intraperitoneally in the repair of large defects of the abdominal wall, reflections on a limited case series].

    PubMed

    Miro, A G; Auciello, I; Loffredo, D; Arenga, G; Lombardi, D

    1999-01-01

    To evaluate the best prosthetic material in direct contact with intestinal loops in the repair of large abdominal wall defects, four cases were reevaluated and an extensive review of the literature was undertake to point out the pathophysiology of prosthetic materials in abdominal wall surgery. For its intrinsic features, Gore-Tex represents the best prosthetic material to locate intraperitoneally, but the slow foreign body reaction is responsible for postoperative complications (e.g. hematoma, seroma, dehiscence). Marlex should not be used in direct contact with intestine because of the risk of multiple fistulas, very difficult to treat, while, the intense foreign body reaction rapidly integrate the mesh into the abdominal wall. To treat large abdominal wall defects are now been proposed mixed prostheses (Gore-Tex in intraperitoneal location, Marlex at the exterior) and dual mesh Gore-Tex (two textures at different microporosity on each side of the mesh). Preliminary studies have shown the safety and utility of these prostheses. PMID:10434463

  20. Relationship between intra-abdominal pressure and vaginal wall movements during Valsalva in women with and without pelvic organ prolapse: technique development and early observations

    PubMed Central

    Spahlinger, D. M.; Newcomb, L.; Ashton-Miller, J. A.; DeLancey, J. O. L.; Chen, Luyun

    2014-01-01

    Objectives To develop and test a method for measuring the relationship between the rise in intra-abdominal pressure and sagittal plane movements of the anterior and posterior vaginal walls during Valsalva in a pilot sample of women with and without prolapse. Methods Mid-sagittal MRI images were obtained during Valsalva while changes in intra-abdominal pressure were measured via a bladder catheter in 5 women with cystocele, 5 women with rectocele, and 5 controls. The regional compliance of the anterior and posterior vagina wall support systems were estimated from the ratio of displacement (mm) of equidistant points along the anterior and posterior vaginal walls to intra-abdominal pressure rise (mmHg). Results The compliance of both anterior and posterior vaginal wall support systems varied along different regions of vaginal wall for all three groups, with the highest compliance found near the vaginal apex and the lowest near the introitus. Women with cystocele had more compliant anterior and posterior vaginal wall support systems than women with rectocele. The movement direction differs between cystocele and rectocele. In cystocele, the anterior vaginal wall moves mostly toward the vaginal orifice in the upper vagina, but in a ventral direction in the lower vagina. In rectocele, the direction of the posterior vaginal wall movement is generally toward the vaginal orifice. Conclusions Movement of the vaginal wall and compliance of its support is quantifiable and was found to vary along the length of the vagina. Compliance was greatest in the upper vagina of all groups. Women with cystocele demonstrated the most compliant vaginal wall support. PMID:24474605

  1. Current-driven vortex domain wall motion in wire-tube nanostructures

    NASA Astrophysics Data System (ADS)

    Espejo, A. P.; Vidal-Silva, N.; López-López, J. A.; Goerlitz, D.; Nielsch, K.; Escrig, J.

    2015-03-01

    We have investigated the current-driven domain wall motion in nanostructures comprised of a pair of nanotube and nanowire segments. Under certain values of external magnetic fields, it is possible to pin a vortex domain wall in the transition zone between the wire and tube segments. We explored the behavior of this domain wall under the action of an electron flow applied in the opposite direction to the magnetic field. Thus, for a fixed magnetic field, it is possible to release a domain wall pinned simply by increasing the intensity of the current density, or conversely, for a fixed current density, it is possible to release the domain wall simply decreasing the magnetic external field. When the domain wall remains pinned due to the competition between the current density and the magnetic external field, it exhibits a oscillation frequency close to 8 GHz. The amplitude of the oscillations increases with the current density and decreases over time. On the other hand, when the domain wall is released and propagated through the tube segment, this shows the standard separation between a steady and a precessional regime. The ability to pin and release a domain wall by varying the geometric parameters, the current density, or the magnetic field transforms these wire-tube nanostructures in an interesting alternative as an on/off switch nano-transistor.

  2. Current-driven vortex domain wall motion in wire-tube nanostructures

    SciTech Connect

    Espejo, A. P.; Vidal-Silva, N.; López-López, J. A.; Goerlitz, D.; Nielsch, K.; Escrig, J.

    2015-03-30

    We have investigated the current-driven domain wall motion in nanostructures comprised of a pair of nanotube and nanowire segments. Under certain values of external magnetic fields, it is possible to pin a vortex domain wall in the transition zone between the wire and tube segments. We explored the behavior of this domain wall under the action of an electron flow applied in the opposite direction to the magnetic field. Thus, for a fixed magnetic field, it is possible to release a domain wall pinned simply by increasing the intensity of the current density, or conversely, for a fixed current density, it is possible to release the domain wall simply decreasing the magnetic external field. When the domain wall remains pinned due to the competition between the current density and the magnetic external field, it exhibits a oscillation frequency close to 8 GHz. The amplitude of the oscillations increases with the current density and decreases over time. On the other hand, when the domain wall is released and propagated through the tube segment, this shows the standard separation between a steady and a precessional regime. The ability to pin and release a domain wall by varying the geometric parameters, the current density, or the magnetic field transforms these wire-tube nanostructures in an interesting alternative as an on/off switch nano-transistor.

  3. Near and far-wall effects on the three-dimensional motion of bacteria-driven microbeads

    NASA Astrophysics Data System (ADS)

    Edwards, Matthew R.; Wright Carlsen, Rika; Sitti, Metin

    2013-04-01

    Bio-hybrid microrobots have been heavily studied due to their potential applications as minimally invasive medical microdevices. Though most researchers have focused on two-dimensional and near-wall motion, this letter uses a defocused optical tracking method to quantify the three-dimensional motion of 5 μm diameter polystyrene beads driven by attached Serratia marcescens bacteria. Away from walls the beads trace out helical trajectories, demonstrating kinematics produced by near-constant forces and torques. Near-wall motion is observed to be more stochastic. The motion of beads driven by single bacteria is analyzed in detail, providing an understanding of the forces and torques on the beads.

  4. Effects of Chitosan Coatings on Polypropylene Mesh for Implantation in a Rat Abdominal Wall Model

    PubMed Central

    Udpa, Natasha; Iyer, Shama R.; Rajoria, Rohit; Breyer, Kate E.; Valentine, Helen; Singh, Bhupinder; McDonough, Sean P.; Brown, Bryan N.; Bonassar, Lawrence J.

    2013-01-01

    Hernia repair and pelvic floor reconstruction are usually accompanied with the implantation of a surgical mesh, which frequently results in a foreign body response with associated complications. An ideal surgical mesh that allows force generation of muscle tissues without significant granulation tissue and/or fibrosis is of significant clinical interest. The objective of the present study was to evaluate the in vitro and in vivo responses of a chitosan coating on polypropylene mesh (Ch-PPM) in comparison with commercially available meshes. We found that application of a 0.5% (w/v) Ch-PPM elicited preferential attachment of myoblasts over fibroblast attachment in vitro. Therefore, we test the hypothesis that 0.5% Ch-PPM will encourage skeletal muscle tissue ingrowth and decrease fibrosis formation in vivo. We implanted 0.5% Ch-PPM, collagen-coated polypropylene mesh (Pelvitex™; C.R. Bard), and polypropylene (Avaulta Solo®; C.R. Bard) alone using a rat abdominal defect model. Force generation capacity and inflammatory response of each mesh were evaluated 2, 4, and 12 weeks postimplantation. We found that chitosan coating is associated with the restoration of functional skeletal muscle with histomorphologic characteristics that resemble native muscle and an early macrophage phenotypic response that has previously been shown to lead to more functional outcomes. PMID:23859182

  5. Current-driven domain wall motion enhanced by the microwave field

    SciTech Connect

    Wang, Xi-guang; Guo, Guang-hua Nie, Yao-zhuang; Wang, Dao-wei; Li, Zhi-xiong; Tang, Wei; Zeng, Zhong-ming

    2014-07-14

    The magnetic domain wall (DW) motion driven by a spin-polarized current opens a new concept for memory and logic devices. However, the critical current density required to overcome the intrinsic and/or extrinsic pinning of DW remains too large for practical applications. Here, we show, by using micromagnetic simulations and analytical approaches, that the application of a microwave field offers an effective solution to this problem. When a transverse microwave field is applied, the adiabatic spin-transfer torque (STT) alone can sustain a steady-state DW motion without the sign of Walker breakdown, meaning that the intrinsic pinning disappears. The extrinsic pinning can also be effectively reduced. Moreover, the DW velocity is increased greatly for the microwave-assisted DW motion. This provides a new way to manipulate the DW motion at low current densities.

  6. Emergence of electromotive force in precession-less rigid motion of deformed domain wall

    NASA Astrophysics Data System (ADS)

    Farajollahpour, Tohid; Darmiani, Narges; Phirouznia, Arash

    2016-08-01

    Recently it has been recognized that the electromotive force (emf) can be induced just by the spin precession where the generation of the electromotive force has been considered as a real-space topological pumping effect. It has been shown that the amount of the electromotive force is independent of the functionality of the localized moments. It was also demonstrated that the rigid domain wall (DW) motion cannot generate electromotive force in the system. Based on real-space topological pumping approach in the current study we show that the electromotive force can be induced by rigid motion of a deformed DW. We also demonstrate that the generated electromotive force strongly depends on the DW bulging. Meanwhile results show that the DW bulging leads to generation of the electromotive force both along the axis of the DW motion and normal to the direction of motion.

  7. Pelvic and abdominal-wall actinomycotic infection by uterus gateway without genital lesions.

    PubMed

    Brezean, I; Aldoescu, S; Catrina, E; Vâlcu, M; Ionuţ, I; Predescu, G; Degeratu, D; Pantea, I

    2010-01-01

    We hereby aim to account on a case of actinomycotic infection occurred in a female patient with an intrauterine contraceptive device (IUCD). The infection occurred as a pseudo-tumour which raised differential diagnosis issues with a malignant tumour. The diagnosis has been eventually established following the pathologic examination of paraffin-embedded tissues. Although the infection's gateway was the uterus, the subsequent invasion of the parietal, urinary bladder and lateral rectal walls did not seem to affect the fallopian tubes or the ovaries. PMID:20405693

  8. Eccrine Porocarcinoma presenting as an abdominal wall mass in a patient with ulcerative colitis—A rare case report

    PubMed Central

    Parmar, Narendrasinh; Mohamed, Mohamed; Elmoghrabi, Adel; McCann, Michael

    2016-01-01

    Introduction Eccrine porocarcinoma (EPC) is a rare malignancy of eccrine sweat glands. It is often seen during the sixth to eighth decades of life. We report the first case of eccrine porocarcinoma arising on the abdomen of a 21-year-old patient with ulcerative colitis. Case presentation A 21-Year-old female presented to emergency department with a one month history of an enlarging mass over left lower abdomen. Abdominal examination revealed a slightly erythematous, nodular and non-mobile firm mass in left lower quadrant. There was superficial ulceration with slight serous discharge. CT scan of the abdomen and pelvis with contrast revealed a superficial cystic lesion over the anterior abdominal wall, provisionally diagnosed as sebaceous cyst. Incision and drainage were performed and on follow-up, no signs of healing were observed and the patient subsequently underwent surgical excision. Histopathological examination revealed an eccrine porocarcinoma. Discussion EPC is a rare and aggressive tumor. It may occur de novo or as a result of malignant transformation of an eccrine poroma. A long period of clinical history is often encountered. It usually occurs on the lower extremities followed by the, trunk, head and neck, and upper extremities. The clinical picture usually consists of a painless nodule or papule. Treatment is wide local excision. No strong evidence exists for adjuvant therapy. The risk of local recurrence is about 20%. Conclusion High index of suspicion is required for diagnosis of EPC. Early diagnosis is achieved by histopathological examination and early definitive surgical excision leads to excellent results. PMID:27085107

  9. Respiratory Motion-Compensated Radial Dynamic Contrast-Enhanced (DCE)-MRI of Chest and Abdominal Lesions

    PubMed Central

    Lin, Wei; Guo, Junyu; Rosen, Mark A.; Song, Hee Kwon

    2016-01-01

    Dynamic contrast-enhanced (DCE)-MRI is becoming an increasingly important tool for evaluating tumor vascularity and assessing the effectiveness of emerging antiangiogenic and antivascular agents. In chest and abdominal regions, however, respiratory motion can seriously degrade the achievable image quality in DCE-MRI studies. The purpose of this work is to develop a respiratory motion-compensated DCE-MRI technique that combines the self-gating properties of radial imaging with the reconstruction flexibility afforded by the golden-angle view-order strategy. Following radial data acquisition, the signal at k-space center is first used to determine the respiratory cycle, and consecutive views during the expiratory phase of each respiratory period (34–55 views, depending on the breathing rate) are grouped into individual segments. Residual intra-segment translation of lesion is subsequently compensated for by an autofocusing technique that optimizes image entropy, while intersegment translation (among different respiratory cycles) is corrected using 3D image correlation. The resulting motion-compensated, undersampled dynamic image series is then processed to reduce image streaking and to enhance the signal-to-noise ratio (SNR) prior to perfusion analysis, using either the k-space-weighted image contrast (KWIC) radial filtering technique or principal component analysis (PCA). The proposed data acquisition scheme also allows for high framerate arterial input function (AIF) sampling and free-breathing baseline T1 mapping. The performance of the proposed radial DCE-MRI technique is evaluated in subjects with lung and liver lesions, and results demonstrate that excellent pixelwise perfusion maps can be obtained with the proposed methodology. PMID:18956465

  10. Analysis of Human's Motions Based on Local Mean Decomposition in Through-wall Radar Detection

    NASA Astrophysics Data System (ADS)

    Lu, Qi; Liu, Cai; Zeng, Zhaofa; Li, Jing; Zhang, Xuebing

    2016-04-01

    Observation of human motions through a wall is an important issue in security applications and search-and rescue. Radar has advantages in looking through walls where other sensors give low performance or cannot be used at all. Ultrawideband (UWB) radar has high spatial resolution as a result of employment of ultranarrow pulses. It has abilities to distinguish the closely positioned targets and provide time-lapse information of targets. Moreover, the UWB radar shows good performance in wall penetration when the inherently short pulses spread their energy over a broad frequency range. Human's motions show periodic features including respiration, swing arms and legs, fluctuations of the torso. Detection of human targets is based on the fact that there is always periodic motion due to breathing or other body movements like walking. The radar can gain the reflections from each human body parts and add the reflections at each time sample. The periodic movements will cause micro-Doppler modulation in the reflected radar signals. Time-frequency analysis methods are consider as the effective tools to analysis and extract micro-Doppler effects caused by the periodic movements in the reflected radar signal, such as short-time Fourier transform (STFT), wavelet transform (WT), and Hilbert-Huang transform (HHT).The local mean decomposition (LMD), initially developed by Smith (2005), is to decomposed amplitude and frequency modulated signals into a small set of product functions (PFs), each of which is the product of an envelope signal and a frequency modulated signal from which a time-vary instantaneous phase and instantaneous frequency can be derived. As bypassing the Hilbert transform, the LMD has no demodulation error coming from window effect and involves no negative frequency without physical sense. Also, the instantaneous attributes obtained by LMD are more stable and precise than those obtained by the empirical mode decomposition (EMD) because LMD uses smoothed local

  11. Abdominal CT scan

    MedlinePlus

    ... tumors, including cancer Infections or injury Kidney stones Appendicitis ... also be due to: Abdominal aortic aneurysm Abscesses Appendicitis Bowel wall thickening Retroperitoneal fibrosis Renal artery stenosis ...

  12. Fluids in micropores. V. Effects of thermal motion in the walls of a slit-micropore

    SciTech Connect

    Diestler, D.J.; Schoen, M.

    1996-05-01

    Previous articles in this series have concerned the prototypal slit-pore with {ital rigid} walls, in which a Lennard-Jones (12,6) monatomic film is constrained between two plane-parallel walls comprising like atoms fixed in the face-centered-cubic (fcc) (100) configuration. The behavior of molecularly thin films in the rigid-wall prototype is governed by the template effect, whereby solid films can form epitaxially when the walls are properly aligned in the lateral directions. In this article the influence of thermal motion of the wall atoms on the template effect is investigated. The walls are treated as Einstein solids, the atoms moving independently in harmonic potentials centered on rigidly fixed equilibrium positions in the fcc (100) configuration. The force constant {ital f}{sub {ital c}} is a measure of the stiffness of the walls, the rigid-wall limit being {ital f}{sub {ital c}}={infinity}. Formal thermodynamic and statistical mechanical analyses of the system are carried out. The results of grand canonical ensemble Monte Carlo simulations indicate that for values of {ital f}{sub {ital c}} characteristic of a soft (e.g., noble-gas) crystal dynamic coupling between wall and film has a substantial influence on such equilibrium properties as normal stress (load) and interfacial tensions. In general, the softer the walls (i.e., the smaller the value of {ital f}{sub {ital c}}), the weaker the template effect and hence the softer and more disordered the confined film. {copyright} {ital 1996 American Institute of Physics.}

  13. Comparison of Intravoxel Incoherent Motion Parameters across MR Imagers and Field Strengths: Evaluation in Upper Abdominal Organs.

    PubMed

    Barbieri, Sebastiano; Donati, Olivio F; Froehlich, Johannes M; Thoeny, Harriet C

    2016-06-01

    Purpose To determine the reproducibility of intravoxel incoherent motion (IVIM) parameters measured in upper abdominal organs with magnetic resonance (MR) imagers from different vendors and with different field strengths. Materials and Methods This prospective study was approved by the independent ethics committees of Kanton Bern and Kanton Zurich, and signed informed consent was obtained from all participants. Abdominal diffusion-weighted images in 10 healthy men (mean age, 37 years ± 8 [standard deviation]) were acquired by using 1.5- and 3.0-T MR imagers from three different vendors. Two readers independently delineated regions of interest that were used to measure IVIM parameters (diffusion coefficient [Dt], perfusion fraction [Fp], and pseudodiffusion coefficient [Dp]) in the left and right lobes of the liver, and in the pancreas, spleen, renal cortex, and renal medulla. Measurement reproducibility between readers was assessed with intraclass correlation coefficients (ICCs). Variability across MR imagers was analyzed by using between- and within-subject coefficients of variation (CVs) and analysis of variance (ANOVA). Results Between-reader reproducibility was high for Dt (ICC, 94.6%), intermediate for Fp (ICC, 81.7%), and low for Dp (ICC, 69.5%). Between- and within-subject CVs of Dt were relatively high (>20%) in the left lobe of the liver and relatively low (<10%) in the renal cortex and renal medulla. CVs generally exceeded 15% for Fp values and 20% for Dp. ANOVA indicated significant differences (P < .05) between MR imagers. Conclusion IVIM parameters in the upper abdomen may differ substantially across MR imagers. (©) RSNA, 2015 Online supplemental material is available for this article. PMID:26678455

  14. Superthin Abdominal Wall Glove-Like Flap Combined With Vacuum-Assisted Closure Therapy for Soft Tissue Reconstruction in Severely Burned Hands or With Infection.

    PubMed

    Wang, Fei; Liu, Sheng; Qiu, Le; Ma, Ben; Wang, Jian; Wang, Yong-Jie; Peszel, April; Chen, Xu-Lin

    2015-12-01

    Severe burn and infection to hands always involves the deep structures, such as tendons, joints, and bones. These wounds cannot be closed immediately and therefore creates a high risk for complication. We presented 9 cases with deep dermal burns to the dorsal of the hand (6 electrical burns and 3 thermal crush injuries) with wound infections in 2 cases. The vacuum-assisted closure system was used continuously until the flap reconstruction was performed. A random pattern and superthin abdominal wall skin flap-like glove was designed. The flap was transferred to the defected portion of the dorsum of the hand and resected from the abdominal wall about 3 weeks later. The flaps in 8 of the patients treated by this technique survived completely and partial necrosis of the distal flap occurred in 1 patient. The defect resolved after operative treatment and the function of the hands and fingers were successfully salvaged. All patients resulted in having a satisfactory aesthetic outcome with no or minor discomfort at the abdominal donor area. Integration of the vacuum-assisted closure system and the superthin abdominal wall glove-like flap reconstruction appeared to be successful and should be considered in patients with severely burned hands. PMID:26418768

  15. Techniques for Abdominal Wall Closure after Damage Control Laparotomy: From Temporary Abdominal Closure to Early/Delayed Fascial Closure—A Review

    PubMed Central

    Huang, Qian; Li, Jieshou; Lau, Wan-yee

    2016-01-01

    Open abdomen (OA) has been an effective treatment for abdominal catastrophes in traumatic and general surgery. However, management of patients with OA remains a formidable task for surgeons. The central goal of OA is closure of fascial defect as early as is clinically feasible without precipitating abdominal compartment syndrome. Historically, techniques such as packing, mesh, and vacuum-assisted closure have been developed to assist temporary abdominal closure, and techniques such as components separation, mesh-mediated traction, bridging fascial defect with permanent synthetic mesh, or biologic mesh have also been attempted to achieve early primary fascial closure, either alone or in combined use. The objective of this review is to present the challenges of these techniques for OA with a goal of early primary fascial closure, when the patient's physiological condition allows. PMID:26819597

  16. Techniques for Abdominal Wall Closure after Damage Control Laparotomy: From Temporary Abdominal Closure to Early/Delayed Fascial Closure-A Review.

    PubMed

    Huang, Qian; Li, Jieshou; Lau, Wan-Yee

    2016-01-01

    Open abdomen (OA) has been an effective treatment for abdominal catastrophes in traumatic and general surgery. However, management of patients with OA remains a formidable task for surgeons. The central goal of OA is closure of fascial defect as early as is clinically feasible without precipitating abdominal compartment syndrome. Historically, techniques such as packing, mesh, and vacuum-assisted closure have been developed to assist temporary abdominal closure, and techniques such as components separation, mesh-mediated traction, bridging fascial defect with permanent synthetic mesh, or biologic mesh have also been attempted to achieve early primary fascial closure, either alone or in combined use. The objective of this review is to present the challenges of these techniques for OA with a goal of early primary fascial closure, when the patient's physiological condition allows. PMID:26819597

  17. Clinical significance of exercise-induced left ventricular wall motion abnormality occurring at a low heart rate

    SciTech Connect

    Kimchi, A.; Rozanski, A.; Fletcher, C.; Maddahi, J.; Swan, H.J.; Berman, D.S.

    1987-10-01

    We studied the relationship between the heart rate at the time of onset of exercise-induced wall motion abnormality and the severity of coronary artery disease in 89 patients who underwent exercise equilibrium radionuclide ventriculography as part of their evaluation for coronary artery disease. Segmental wall motion was scored with a five-point system (3 = normal; -1 = dyskinesis); a decrease of one score defined the onset of wall motion abnormality. The onset of wall motion abnormality at less than or equal to 70% of maximal predicted heart rate had 100% predictive accuracy for coronary artery disease and higher sensitivity than the onset of ischemic ST segment depression at similar heart rate during exercise: 36% (25 of 69 patients with coronary disease) vs 19% (13 of 69 patients), p = 0.01. Wall motion abnormality occurring at less than or equal to 70% of maximal predicted heart rate was present in 49% of patients (23 of 47) with critical stenosis (greater than or equal to 90% luminal diameter narrowing), and in only 5% of patients (2 of 42) without such severe stenosis, p less than 0.001. The sensitivity of exercise-induced wall motion abnormality occurring at a low heart rate for the presence of severe coronary artery disease was similar to that of a deterioration in wall motion by more than two scores during exercise (49% vs 53%) or an absolute decrease of greater than or equal to 5% in exercise left ventricular ejection fraction (49% vs 45%).

  18. Dynamic Interplay of Coherent Rotations and Domain Wall Motion in Faraday Rotators based on Ferromagnetic Crystals

    NASA Astrophysics Data System (ADS)

    Garzarella, Anthony; Wu, Dong; Shinn, Mannix

    Under small, externally-applied magnetic fields, the Faraday rotation in magneto-optic material containing ferromagnetic domains is driven primarily by two principal mechanisms: domain wall motion and coherent domain rotations. Domain wall motion yields a larger Faraday responsivity but is limited by magnetically induced optical incoherence and by damping effects. Coherent domain rotation yields smaller Faraday rotations, but exhibits a flatter and broader frequency response. The two mechanisms occur along orthogonal principal axes and may be probed independently. However, when probed along an oblique angle to the principal axes, the relationship between the Faraday rotation and the external field changes from linear to tensorial. Although this may lead to more complicated phenomena (e.g. a sensitivity axis that depends on RF frequency), the interplay of domain rotation and domain wall motion can be exploited to improve responsivity or bandwidth. The detailed experimental data can be understood in terms of a quantitative model for the magnitude and direction of the responsivity vector. Applications to magnetic field sensors based on arrayed bismuth doped iron garnet films will be emphasized in this presentation.

  19. Spontaneous alterations in left ventricular regional wall motion after acute myocardial infarction.

    PubMed

    Shen, W F; Cui, L Q; Wang, M H; Gong, L S; Lesbre, J P

    1990-12-01

    For assessing the relationship between the left ventricular (LV) wall motion abnormalities and the status of residual flow to the infarcted region, the extent of coronary artery disease and one-year outcome, 60 patients with a first transmural, Q-wave myocardial infarction (MI) underwent serial echocardiographic examinations. The abnormal wall motion (AWM) score was calculated, and the cardiac events (death, reinfarction, severe ventricular arrhythmia or congestive heart failure) after discharge were recorded. The AWM score of the infarcted area was higher in patients with total occlusion than in those with subtotal occlusion (anterior MI: 14.6 +/- 2.4 vs 7.2 +/- 2.1; inferior MI: 9.7 +/- 2.1 vs 5.1 +/-1.2, all P less than 0.01). Regional wall motion of the noninfarcted area was preserved in patients with single vessel disease but decreased in those with multivessel disease. In patients who developed cardiac events in follow-up period a higher AWM (16.4 +/- 3.7) was found than in those who did not (8.9 +/- 3.1, P less than 0.05). A score of greater than 13 had a strong prediction of cardiac events after acute MI, with a sensitivity of 81%, specificity of 94% and positive predictive accuracy of 88%. PMID:2127245

  20. Oscillatory motion based measurement method and sensor for measuring wall shear stress due to fluid flow

    DOEpatents

    Armstrong, William D.; Naughton, Jonathan; Lindberg, William R.

    2008-09-02

    A shear stress sensor for measuring fluid wall shear stress on a test surface is provided. The wall shear stress sensor is comprised of an active sensing surface and a sensor body. An elastic mechanism mounted between the active sensing surface and the sensor body allows movement between the active sensing surface and the sensor body. A driving mechanism forces the shear stress sensor to oscillate. A measuring mechanism measures displacement of the active sensing surface relative to the sensor body. The sensor may be operated under periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor measurably changes the amplitude or phase of the motion of the active sensing surface, or changes the force and power required from a control system in order to maintain constant motion. The device may be operated under non-periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor change the transient motion of the active sensor surface or change the force and power required from a control system to maintain a specified transient motion of the active sensor surface.

  1. Assessment of tissue Doppler imaging measurements of arterial wall motion using a tissue mimicking test rig.

    PubMed

    Thrush, Abigail J; Brewin, Mark P; Birch, Malcolm J

    2008-03-01

    The aim of this in vitro study is to assess the accuracy of the tissue Doppler imaging arterial wall motion (TDI AWM) technique in measuring dilation over a range of distances and velocities. A test rig, consisting of two parallel blocks of tissue mimicking material (TMM), has been developed to generate known wall motion. One block remains stationary while the other moves in a cyclical motion. A calibrated laser range finder was used to measure the TMM motion. The TDI AWM measurements were found to underestimate the dilation by 21% +/- 4.7% when using the recommended scanner parameters. The size of the error was found to increase with a decrease in ultrasound output power. Results suggested that errors in the TDI AWM dilation measurements relate to underestimates in the velocity measured by the TDI technique. The error demonstrated in this study indicates a limitation in the value of TDI AWM result obtained in vivo. (E-mail: abigail.thrush@bartsandthelondon.nhs.uk). PMID:17964065

  2. 90-degree polarization switching in BaTiO3 crystals without domain wall motion

    NASA Astrophysics Data System (ADS)

    Li, Y. W.; Scott, J. F.; Fang, D. N.; Li, F. X.

    2013-12-01

    We report 90° polarization switching in a BaTiO3 crystal without domain wall (DW) motion by prefabricating samples with interlocking domains via compression. During electric re-poling of the depoled and aged crystals, 90° domain nucleation still exists, but 90° DW motion is inhibited by the strong constraints from surrounding domains, leading to DW-free 90° polarization switching. The measured coercive field of 500 V/mm for the DW-free 90° switching is close to the intrinsic values and much larger than that of 80 V/mm via 90° DW motion. Compared to the rather difficult domain-free 180° polarization switching in ultrathin films, 90° DW-free switching is easier.

  3. Expansion abdominoplasty for a pregnant woman with severe abdominal wall contracture due to a major burn during childhood: a case report.

    PubMed

    Takeda, Kohsuke; Sowa, Yoshihiro; Numajiri, Toshiaki; Nishino, Kenichi

    2013-06-01

    Normal abdominal expansion that occurs as a result of hormonal actions during pregnancy may be prevented by the presence of excessive scar tissue in individuals who have received severe burns. In these instances, the lack of abdominal expansion may cause maternal pain and put the infant at risk. A 23-year-old pregnant woman presented with severe abdominal wall contracture due to a major burn sustained during childhood. At 20 weeks of pregnancy, expansion abdominoplasty, consisting of zigzag incisions in the fascia to release the contracture and a split-thickness skin graft, was performed. The patient gave birth, via a planned cesarean operation at 36 weeks of pregnancy, to a baby girl in good condition; the postpartum course was uneventful. PMID:23673563

  4. Real-time measurements of local myocardium motion and arterial wall thickening.

    PubMed

    Kanai, H; Koiwa, Y; Zhang, J

    1999-01-01

    We have already developed a new method, namely, the phased tracking method, to track the movement of the heart wall and arterial wall accurately based on both the phase and magnitude of the demodulated signals to determine the instantaneous position of an object. This method has been realized by an off-line measurement system, which cannot be applied to transient evaluation of rapid response of the cardiovascular system to physiological stress. In this paper, therefore, a real-time system to measure change in the thickness of the myocardium and the arterial wall is presented. In this system, an analytic signal from standard ultrasonic diagnostic equipment is analogue-to-digital (A/D) converted at a sampling frequency of 1 MHz. By pipelining and parallel processing using four high-speed digital signal processing (DSP) chips, the method described is realized in real time. The tracking results for both sides of the heart and/or arterial wall are superimposed on the M (motion)-mode image in the work station (WS), and the thickness changes of the heart and/or arterial wall are also displayed and digital-to-analogue (D/A) converted in real time. From the regional change in thickness of the heart wall, spatial distribution of myocardial motility and contractility can be evaluated. For the arterial wall, its local elasticity can be evaluated by referring to the blood pressure. In in vivo experiments, the rapid response of the change in wall thickness of the carotid artery to the dose of the nitroglycerine (NTG) is evaluated. This new real-time system offers potential for quantitative diagnosis of myocardial motility, early stage atherosclerosis, and the transient evaluation of the rapid response of the cardiovascular system to physiological stress. PMID:18244316

  5. CRITICAL ANALYSIS OF EXPERIMENTAL MODEL FOR STUDY OF ADHESIONS AFTER INCISIONAL HERNIAS INDUCED IN RATS’ AND REPAIR OF ABDOMINAL WALL WITH DIFFERENT BIOMATERIALS

    PubMed Central

    SERIGIOLLE, Leonardo Carvalho; BARBIERI, Renato Lamounier; GOMES, Helbert Minuncio Pereira; RODRIGUES, Daren Athiê Boy; STUDART, Sarah do Valle; LEME, Pedro Luiz Squilacci

    2015-01-01

    Background: Adhesions induced by biomaterials experimentally implanted in the abdominal cavity are basically studied by primary repair of different abdominal wall defects or by the correction of incisional hernias previously performed with no precise definition of the most appropriate model. Aim: To describe the adhesions which occur after the development of incisional hernias, before the prosthesis implantation, in an experimental model to study the changes induced by different meshes. Methods: Incisional hernias were performed in 10 rats with hernia orifices of standardized dimensions, obtained by the median incision of the abdominal wall and eversion of the defect edges. Ten days after the procedure adhesions of abdominal structures were found when hernias were repaired with different meshes. Results: The results showed hernia sac well defined in all rats ten days after the initial procedure. Adhesions of the greater omentum occurred in five animals of which two also showed adhesions of small bowel loops besides the omentum, and another two showed liver adhesions as well as the greater omentum, numbers with statistical significance by Student's t test (p<0.05). Conclusion: Although it reproduces the real clinical situation, the choice of experimental model of incisional hernia repair previously induced implies important adhesions, with possible repercussions in the evaluation of the second operation, when different implants of synthetic materials are used. PMID:26537141

  6. The preferential contraction ratios of transversus abdominis on the variations of knee angles during abdominal drawing-in maneuver in wall support standing

    PubMed Central

    Hwang, Young-In; Kim, Jwa-Jun; Park, Du-Jin

    2014-01-01

    The objective of this study was to determine appropriate knee angles for the abdominal drawing-in maneuver (ADIM) through evaluation of changes in contraction ratios of the abdominal muscles and activity of quadriceps muscle in relation to changes in knee angles occurring while the ADIM is performed in the wall support standing (WSS). 20 subjects performed the ADIM at different knee angles (0°, 20°, 40°, 60°) in random order, standing at a point 6 inches away from the wall with the spine maintained in the neutral position. The WSS with knee flexion at 20° showed significantly higher preferential contraction ratio (PCR) of transversus abdominis (TrA) compared to other positions (0°, 40°, 60°). Therefore, performing the ADIM in the WSS with knee flexion at 20° appears to be the most appropriate position for TrA PCR. PMID:24877045

  7. Reconstruction of the Abdominal Wall in Anatomical Plans. Pre- and Postoperative Keys in Repairing “Cold” Incisional Hernias

    PubMed Central

    POPA, FLORINA; ROSCA, OANA; GEORGESCU, ALEXANDRU; CANNISTRA, CLAUDIO

    2016-01-01

    Background and aims The clinical results of the vertical “vest-over-pants” Mayo repair were evaluated, and the risk factors for incisional hernia recurrence were studied. The purpose of this study is to point out the importance of reducing pre and post operative risk factors in the incisional hernia repair process in order to achieve a physiologically normal abdominal wall. Methods Twenty patients diagnosed with incisional hernia underwent an abdominal reconstruction procedure using the Mayo (Paletot) technique at Bichat Claude Bernard Hospital between 2005 and 2015. All procedures were performed by a single surgeon and all patients were pre-operatively prepared, identifying all coexisting conditions and treating them accordingly before undergoing surgery. Results All patients underwent at least one surgical operation before the hernia repair procedure and a quarter had experienced at least three, prior to this one. Nine patients had a body mass index of >30 kg/m2. Additional risk factors and comorbidities included obesity in 45%, diabetes mellitus in 10%, smoking in 55%, and high blood pressure in 40%. Hernia defect width was from 3 cm (25% F) to 15 cm (5% M) of which nine patients (45%) had a 10 cm defect. Most of the patients had an average hospitalization of 7 days. The patients were carefully monitored and were called on periodic consultations after 3, 6, and 12 months from the moment of the procedure. Patient feedback regarding hernia recurrence and complaints about the scar were noted. Physical examination is essential in determining the hernia recurrence therefore the scar was examined for any abnormalities that may have occurred, which was defined as any palpable or detected fascial defect located within seven centimeters of the hernia repair. Post-operative complications: seroma formation, wound hematoma, superficial and deep wound infection, recurrences and chronic pain were followed and no complications were registered during the follow-up period

  8. Current-induced domain wall motion in permalloy nanowires with a rectangular cross-section

    SciTech Connect

    Ai, J. H.; Miao, B. F.; Sun, L.; You, B.; Hu, An; Ding, H. F.

    2011-11-01

    We performed micromagnetic simulations of the current-induced domain wall motion in permalloy nanowires with rectangular cross-section. In the absence of the nonadiabatic spin-transfer term, a threshold current, J{sub c} is required to drive the domain wall moving continuously. We find that J{sub c} is proportional to the maximum cross product of the demagnetization field and magnetization orientation of the domain wall and the domain wall width. With varying both the wire thickness and width, a minimum threshold current in the order of 10{sup 6} A/cm{sup 2} is obtained when the thickness is equivalent to the wire width. With the nonadiabatic spin-transfer term, the calculated domain wall velocity {nu} equals to the adiabatic spin transfer velocity u when the current is far above the Walker limit J{sub w}. Below J{sub w}, {nu}=({beta}/{alpha})u, where {beta} is the nonadiabatic parameter and {alpha} is the damping factor. For different {beta}, we find the Walker limit can be scaled as J{sub w}=({alpha}/{beta}-{alpha})J{sub c}. Our simulations agree well with the one dimensional analytical calculation, suggesting the findings are the general behaviors of the systems in this particular geometry.

  9. Relaxation of H/sub 2/ vibrational motion by wall collisions

    SciTech Connect

    Karo, A.M.; DeBoni, T.M.; Hiskes, J.R.

    1980-01-01

    The method of computer molecular dynamics was applied to an important technological problem where experimental data may be extremely difficult to obtain: collisional de-excitation at surfaces of vibrationally highly excited hydrogen molecules. The calculations have been carried out primarily for vibrational states about the v = 6 level. The technique is illustrated by means of a specific example and the detail that can be obtained from such calculations concerning the dynamics of the interaction is shown. Molecular states excited to the v = 4, v = 6, and v = 11 vibrational levels and the J = 1 rotational level have been examined. The translational temperature of the molecules is chosen to be 500/sup 0/K, and the wall is given thermal motion characteristic of a temperature of 500/sup 0/K. Different angles of approach have been studied, and different impact points on the surface have been selected. After the first collision, the impact point becomes random because of the stochastic nature of subsequent molecular trajectories. For any given collision with the wall, the molecule may pick up or lose vibrational, rotational, and translational energy. Careful sampling and averaging of the results of many trajectory runs is needed in order to arrive at meaningful conclusions about the probability of de-excitation as a function of such parameters as the number of wall collisions, the residence time, the wall temperature, and the microscopic nature of the wall itself.

  10. Successful treatment of mesenteric varices by retrograde transvenous obliteration by the delivery of N-butyl-2-cyanoacrylate via an abdominal wall vein.

    PubMed

    Ikeda, Osamu; Nakasone, Yutaka; Yokoyama, Koichi; Inoue, Seijiro; Takamori, Hiroshi; Baba, Hideo; Yamashita, Yasuyuki

    2014-04-01

    Bleeding from mesenteric varices associated with portal hypertension is occasionally life-threatening. A 53-year-old man who had undergone esophageal transection for esophageal varices and balloon-occluded retrograde transvenous obliteration for gastric varices presented with melena due to ruptured mesenteric varices. He was treated by injecting N-butyl-2-cyanoacrylate via an abdominal wall vein to obtain retrograde transvenous obliteration. PMID:23716126

  11. An Ultrasound Simulation Model for the Pulsatile Blood Flow Modulated by the Motion of Stenosed Vessel Wall

    PubMed Central

    Zhou, Yi; Zhang, Kun; Zhang, Kexin; Gao, Lian

    2016-01-01

    This paper presents an ultrasound simulation model for pulsatile blood flow, modulated by the motion of a stenosed vessel wall. It aims at generating more realistic ultrasonic signals to provide an environment for evaluating ultrasound signal processing and imaging and a framework for investigating the behaviors of blood flow field modulated by wall motion. This model takes into account fluid-structure interaction, blood pulsatility, stenosis of the vessel, and arterial wall movement caused by surrounding tissue's motion. The axial and radial velocity distributions of blood and the displacement of vessel wall are calculated by solving coupled Navier-Stokes and wall equations. With these obtained values, we made several different phantoms by treating blood and the vessel wall as a group of point scatterers. Then, ultrasound echoed signals from oscillating wall and blood in the axisymmetric stenotic-carotid arteries were computed by ultrasound simulation software, Field II. The results show better consistency with corresponding theoretical values and clinical data and reflect the influence of wall movement on the flow field. It can serve as an effective tool not only for investigating the behavior of blood flow field modulated by wall motion but also for quantitative or qualitative evaluation of new ultrasound imaging technology and estimation method of blood velocity. PMID:27478840

  12. An Ultrasound Simulation Model for the Pulsatile Blood Flow Modulated by the Motion of Stenosed Vessel Wall.

    PubMed

    Zhang, Qinghui; Zhang, Yufeng; Zhou, Yi; Zhang, Kun; Zhang, Kexin; Gao, Lian

    2016-01-01

    This paper presents an ultrasound simulation model for pulsatile blood flow, modulated by the motion of a stenosed vessel wall. It aims at generating more realistic ultrasonic signals to provide an environment for evaluating ultrasound signal processing and imaging and a framework for investigating the behaviors of blood flow field modulated by wall motion. This model takes into account fluid-structure interaction, blood pulsatility, stenosis of the vessel, and arterial wall movement caused by surrounding tissue's motion. The axial and radial velocity distributions of blood and the displacement of vessel wall are calculated by solving coupled Navier-Stokes and wall equations. With these obtained values, we made several different phantoms by treating blood and the vessel wall as a group of point scatterers. Then, ultrasound echoed signals from oscillating wall and blood in the axisymmetric stenotic-carotid arteries were computed by ultrasound simulation software, Field II. The results show better consistency with corresponding theoretical values and clinical data and reflect the influence of wall movement on the flow field. It can serve as an effective tool not only for investigating the behavior of blood flow field modulated by wall motion but also for quantitative or qualitative evaluation of new ultrasound imaging technology and estimation method of blood velocity. PMID:27478840

  13. A memristor based on current-induced domain-wall motion in a nanostructured giant magnetoresistance device

    NASA Astrophysics Data System (ADS)

    Münchenberger, Jana; Reiss, Günter; Thomas, Andy

    2012-04-01

    The possibility of controlling the resistance of a memristive giant magnetoresistance (GMR) system via current-induced domain-wall motion was investigated. For a narrow spin-valve structure, current-induced domain-wall motion in the free layer can be detected once the current density exceeds a critical threshold. Then, the resistance of the device depends on the position of the domain wall. The GMR system shows a MR ratio of 10% in the as-prepared state. Narrow stripes were fabricated by e-beam lithography and ion-beam etching with a width of 200 nm. The stripes exhibit GMR ratios up to 8% at room temperature. Micromagnetic simulations of the domain-wall motion in the free layer allow an estimation of the time scale of the domain-wall migration in the stripe. Furthermore, the simulations were compared with measured critical current densities in the free layer with and without an applied external field.

  14. Electric-Field Control over Spin-Wave and Current Induced Domain Wall Motion and Magnonic Torques in Multiferroics

    NASA Astrophysics Data System (ADS)

    Kulagina, Iryna; Linder, Jacob

    2015-03-01

    We discover that the way spin-waves exert magnetic torques in multiferroic materials can cause not only domain wall motion, but also magnetization dynamics for homogeneous magnetization textures. Interestingly, the domain wall motion can be controlled via purely electrical means with the spin-waves being generated by an ac electric field E while the direction of the wall motion also is sensitive to an applied dc E field. Moreover, we determine the interaction between spin-transfer torque from an electric current and a magnetic domain wall in multiferroics and show that the Walker breakdown threshold scales with the magnitude of a perpendicular electric field, offering a way to control the properties of domain wall propagation via electric gating.

  15. Magnetic domain-wall motion twisted by nanoscale probe-induced spin transfer

    NASA Astrophysics Data System (ADS)

    Wang, J.; Xie, L. S.; Wang, C. S.; Zhang, H. Z.; Shu, L.; Bai, J.; Chai, Y. S.; Zhao, X.; Nie, J. C.; Cao, C. B.; Gu, C. Z.; Xiong, C. M.; Sun, Y.; Shi, J.; Salahuddin, S.; Xia, K.; Nan, C. W.; Zhang, J. X.

    2014-12-01

    A method for deterministic control of magnetism using an electrical stimulus is highly desired for the new generation of magnetoelectronic devices. Much effort has been focused on magnetic domain-wall (DW) motion manipulated by a successive injection of spin-polarized current into a magnetic nanostructure. However, an integrant high-threshold current density of 1011˜1012A /m2 inhibits the integration with low-energy-cost technology. Here, we report an approach to manipulate a single magnetic domain wall with a perpendicular anisotropy in a manganite/dielectric/metal capacitor using a probe-induced spin displacement. A spin-transfer torque (STT) occurs in the strongly correlated manganite film during the spin injection into the capacitor from the nanoscale magnetized tip with an ultralow voltage of 0.1 V, where a lower bound of the estimated threshold spin-polarized current density is ˜108A /m2 at the tip/manganite interface. The dynamic of DW motions are analyzed using the Landau-Lifshitz-Gilbert method. This probe-voltage-controlled DW motion, at an ambient condition, demonstrates a critical framework for the fundamental understanding of the manipulation of the nanomagnet systems with low-energy consumption.

  16. The in vivo evaluation of tissue-based biomaterials in a rat full-thickness abdominal wall defect model.

    PubMed

    Bryan, Nicholas; Ahswin, Helen; Smart, Neil; Bayon, Yves; Wohlert, Stephen; Hunt, John A

    2014-05-01

    Hernias are defects in which an anatomical fascia is breached resulting in ectopic positioning of an organ into an orifice which routinely does not contain it. Intervention often involves repositioning translocated organs and repair of damaged fascia using exogenous grafts. Despite hernia prevalence, repairs can still fail due to postoperative complications, such as chronic pain and decreased mobility. This study compared repair capacities and characterized the foreign body response elicited by a number of hernia repair grafts to deduce their bulk inflammatory properties while also concluding the point in their fabrication when these are inferred. Materials derived from human dermis (Alloderm(®) ), porcine dermis (Permacol™, patch A, patch D and Strattice(®) ), porcine small-intestinal submucosa (Surgisis™) and a synthetic (multifilament Surgipro™) were implanted into a rat full-thickness abdominal wall excision model, incubated for up to 2 years and characterized histopathologically. Surgisis™ resorbed the fastest of the materials tested (1-3 months) resulting in a mechanically stable parietal peritoneum. Decellularization using sodium dodecyl sulfate (patch A) stimulated a large early inflammatory response which ultimately may have contributed to increased resorption of porcine dermal matrix however the remaining materials typically persisted throughout the 2-year incubation. Cross-linking porcine dermis using 1,6-hexamethylene disocyanate (vs. an identical noncross-linked counterpart) showed no difference in cell recruitment or material integration over 2 years. Typically Strattice(®) and Alloderm(®) recruited larger early populations of cells than Permacol™; however, over extended periods of time in vivo this response normalized. PMID:24155173

  17. Image-guided intensity-modulated radiotherapy for refractory bilateral breast cancer in a patient with extensive cutaneous metastasis in the chest and abdominal walls

    PubMed Central

    Lu, Yueh-Feng; Lin, Yu-Chin; Chen, Kuo-Hsin; Shueng, Pei-Wei; Yeh, Hsin-Pei; Hsieh, Chen-Hsi

    2016-01-01

    Treatment for bilateral breast cancer with chest wall and abdominal skin invasion normally involves conventional radiotherapy (RT); however, conventional RT provides inadequate target volume coverage and excessive treatment of large volumes of normal tissue. Helical tomotherapy (HT) has the ability to deliver continuous craniocaudal irradiation that suppresses junction problems and provides good conformity of dose distribution. A 47-year-old female with stage IV bilateral breast cancer with chest wall and pectoralis major muscle invasion, lymphadenopathy, bilateral pleural effusion, and multiple bone metastases received chemotherapy and target therapy beginning in January 2014; 4 months after the initiation of chemotherapy, computed tomography revealed progression of chest and abdominal wall invasion. A total dose of 70.2 Gy was delivered to both breasts, the chest wall, the abdominal wall, and the bilateral supraclavicular nodal areas in 39 fractions via HT. The total planning target volume was 4,533.29 cm3. The percent of lung volume receiving at least 20 Gy (V20) was 28%, 22%, and 25% for the right lung, left lung, and whole lung, respectively. The mean dose to the heart was 8.6 Gy. Follow-up computed tomography revealed complete response after the RT course. Grade 1 dysphagia, weight loss, grade 2 neutropenia, and grade 3 dermatitis were noted during the RT course. Pain score decreased from 6 to 1. No cardiac, pulmonary, liver, or intestinal toxicity developed during treatment or follow-up. Concurrent HT with or without systemic treatment could be a safe salvage therapy for chemorefractory locally advanced breast cancer patients with extensive cutaneous metastasis. PMID:27284253

  18. Temperature dependence of carrier spin polarization determined from current-induced domain wall motion in a Co/Ni nanowire

    SciTech Connect

    Ueda, K.; Koyama, T.; Hiramatsu, R.; Kobayashi, K.; Ono, T.; Chiba, D.; Fukami, S.; Tanigawa, H.; Suzuki, T.; Ohshima, N.; Ishiwata, N.; Nakatani, Y.

    2012-05-14

    We have investigated the temperature dependence of the current-induced magnetic domain wall (DW) motion in a perpendicularly magnetized Co/Ni nanowire at various temperatures and with various applied currents. The carrier spin polarization was estimated from the measured domain wall velocity. We found that it decreased more with increasing temperature from 100 K to 530 K than the saturation magnetization did.

  19. Two-dimensional simulation of red blood cell motion near a wall under a lateral force

    NASA Astrophysics Data System (ADS)

    Hariprasad, Daniel S.; Secomb, Timothy W.

    2014-11-01

    The motion of a red blood cell suspended in a linear shear flow adjacent to a fixed boundary subject to an applied lateral force directed toward the boundary is simulated. A two-dimensional model is used that represents the viscous and elastic properties of normal red blood cells. Shear rates in the range of 100 to 600 s-1 are considered, and the suspending medium viscosity is 1 cP. In the absence of a lateral force, the cell executes a tumbling motion. With increasing lateral force, a transition from tumbling to tank-treading is predicted. The minimum force required to ensure tank-treading increases nonlinearly with the shear rate. Transient swinging motions occur when the force is slightly larger than the transition value. The applied lateral force is balanced by a hydrodynamic lift force resulting from the positive orientation of the long axis of the cell with respect to the wall. In the case of cyclic tumbling motions, the orientation angle takes positive values through most of the cycle, resulting in lift generation. These results are used to predict the motion of a cell close to the outer edge of the cell-rich core region that is generated when blood flows in a narrow tube. In this case, the lateral force is generated by shear-induced dispersion, resulting from cell-cell interactions in a region with a concentration gradient. This force is estimated using previous data on shear-induced dispersion. The cell is predicted to execute tank-treading motions at normal physiological hematocrit levels, with the possibility of tumbling at lower hematocrit levels.

  20. An experimental investigation of domain wall motion in polycrystalline Ni during high-rate compressive loading

    NASA Astrophysics Data System (ADS)

    Ghosh, Dipankar; Bah, Abubakarr; Carman, Gregory P.; Ravichandran, Guruswami

    2016-01-01

    This paper describes experimental data on a polycrystalline nickel subjected to compressive loads induced in a split Hopkinson pressure bar test. A perpendicular bias magnetic field with respect to the loading direction is used to orient the domains and a pick-up coil measures the magnetic response of the sample during loading. Utilizing this experimental configuration, this study investigated the coupled effects of the magnetic and mechanical fields on domain wall motion in a polycrystalline magnetostrictive material (Ni) during the high-rate elastic loading. The experimental measurements reveal that the magnitude of the stress-induced magnetization change is dependent upon bias magnetic field.

  1. Nucleation of reversed domain and pinning effect on domain wall motion in nanocomposite magnets

    NASA Astrophysics Data System (ADS)

    Li, Z. B.; Shen, B. G.; Niu, E.; Sun, J. R.

    2013-08-01

    The magnetization behaviors show a strong pinning effect on domain wall motion in optimally melt-spun Pr8Fe87B5 ribbons at room temperature. According to analysis, the coercivity is determined by the nucleation field of reversed domain, and the pinning effect, which results from the weak exchange coupling at interface, makes domain nucleation processes independent and leads to non-uniform magnetization reversals. At a temperature of 60 K, owing to the weak exchange coupling between soft-hard grains, magnetization reversal undergoes processes of spring domain nucleation in soft grains and irreversible domain nucleation in hard grains, and the pinning effect remains strong among hard grains.

  2. Switching local magnetization by electric-field-induced domain wall motion

    NASA Astrophysics Data System (ADS)

    Kakizakai, Haruka; Ando, Fuyuki; Koyama, Tomohiro; Yamada, Kihiro; Kawaguchi, Masashi; Kim, Sanghoon; Kim, Kab-Jin; Moriyama, Takahiro; Chiba, Daichi; Ono, Teruo

    2016-06-01

    Electric field effect on magnetism is an appealing technique for manipulating magnetization at a low energy cost. Here, we show that the local magnetization of an ultrathin Co film can be switched by simply applying a gate electric field without the assistance of any external magnetic field or current flow. The local magnetization switching is explained by nucleation and annihilation of magnetic domains through domain wall motion induced by the electric field. Our results lead to external-field-free and ultralow-energy spintronic applications.

  3. Abdominal wall surgery

    MedlinePlus

    ... Description Your surgery will be done in an operating room in a hospital. You will receive general ... are connected to a video monitor in the operating room that allows the surgeon to see the ...

  4. Abdominal wall surgery

    MedlinePlus

    ... skin. Abdominoplasty can be helpful when: Diet and exercise have not helped improve muscle tone, such as in women who have had more than one pregnancy. Skin and muscle cannot regain its normal tone. ...

  5. Evaluation of side effects of radiofrequency capacitive hyperthermia with magnetite on the blood vessel walls of tumor metastatic lesion surrounding the abdominal large vessels: an agar phantom study

    PubMed Central

    2014-01-01

    Background Magnetite used in an 8-MHz radiofrequency (RF) capacitive heating device can increase the temperature of a specific site up to 45°C. When treating a metastatic lesion around large abdominal vessels via hyperthermia with magnetite, heating-induced adverse effects on these vessels need to be considered. Therefore, this study examined hyperthermia-induced damage to blood vessel walls in vitro. Methods A large agar phantom with a circulatory system consisting of a swine artery and vein connected to a peristaltic pump was prepared. The blood vessels were placed on the magnetite-containing agar piece. Heating was continued for 30 min at 45°C. After heating, a histological study for injury to the blood vessels was performed. Results The inner membrane temperature did not reach 45°C due to the cooling effect of the blood flow. In the heated vessels, vascular wall collagen degenerated and smooth muscle cells were narrowed; however, no serious changes were noted in the vascular endothelial cells or vascular wall elastic fibers. The heated vessel wall was not severely damaged; this was attributed to cooling by the blood flow. Conclusions Our findings indicate that RF capacitive heating therapy with magnetite may be used for metastatic lesions without injuring the surrounding large abdominal vessels. PMID:25114787

  6. ECG-gated blood pool tomography in the determination of left ventricular volume, ejection fraction, and wall motion

    SciTech Connect

    Underwood, S.R.; Ell, P.J.; Jarritt, P.H.; Emanuel, R.W.; Swanton, R.H.

    1984-01-01

    ECG-gated blood pool tomography promises to provide a ''gold standard'' for noninvasive measurement of left ventricular volume, ejection fraction, and wall motion. This study compares these measurements with those from planar radionuclide imaging and contrast ventriculography. End diastolic and end systolic blood pool images were acquired tomographically using an IGE400A rotating gamma camera and Star computer, and slices were reconstructed orthogonal to the long axis of the heart. Left ventricular volume was determined by summing the areas of the slices, and wall motion was determined by comparison of end diastolic and end systolic contours. In phantom experiments this provided an accurate measurement of volume (r=0.98). In 32 subjects who were either normal or who had coronary artery disease left ventricular volume (r=0.83) and ejection fraction (r=0.89) correlated well with those using a counts based planar technique. In 16 of 18 subjects who underwent right anterior oblique X-ray contrast ventriculography, tomographic wall motion agreed for anterior, apical, and inferior walls, but abnormal septal motion which was not apparent by contrast ventriculography, was seen in 12 subjects tomographically. All 12 had disease of the left anterior descending coronary artery and might have been expected to have abnormal septal motion. ECG-gated blood pool tomography can thus determine left ventricular volume and ejection fraction accurately, and provides a global description of wall motion in a way that is not possible from any single planar image.

  7. Steady-state domain wall motion driven by adiabatic spin-transfer torque with assistance of microwave field

    SciTech Connect

    Wang, Xi-guang; Guo, Guang-hua Nie, Yao-zhuang; Xia, Qing-lin; Tang, Wei; Wang, D.; Zeng, Zhong-ming

    2013-12-23

    We have studied the current-induced displacement of a 180° Bloch wall by means of micromagnetic simulation and analytical approach. It is found that the adiabatic spin-transfer torque can sustain a steady-state domain wall (DW) motion in the direction opposite to that of the electron flow without Walker Breakdown when a transverse microwave field is applied. This kind of motion is very sensitive to the microwave frequency and can be resonantly enhanced by exciting the domain wall thickness oscillation mode. A one-dimensional analytical model was established to account for the microwave-assisted wall motion. These findings may be helpful for reducing the critical spin-polarized current density and designing DW-based spintronic devices.

  8. [Subarachnoid hemorrhage complicated with different manifestations of transient abnormal left ventricular wall motion: two case reports].

    PubMed

    Inoue, Fumitaka; Tsuzuki, Takashi; Thoma, Yoshiki; Shiono, Shigeru; Tabuse, Hisayuki; Hoshida, Thoru; Saito, Yoshihiko

    2006-05-01

    Two patients with subarachnoid hemorrhage presented with transient abnormal left ventricular wall motion. Case 1 was a 56-year-old man. Electrocardiography showed ST segment elevation in leads I, II, II, aVL, aVF, V3-V6. Echocardiography showed localized left ventricular hypokinesis around the apical area (takotsubo-like cardiomyopathy). Ejection fraction was 20% (1st hospital day). Troponin T was positive. Case 2 was a 48-year-old woman. Electrocardiography showed ST segment elevation in leads I, aVL, V2-V6 and ST segment depression in leads II, III, aVF, V1. Echocardiography showed diffuse left ventricular hypokinesis. Ejection fraction was 21% (1st hospital day). Troponin T was positive. These two patients had no history of cardiac disease, and coronary angiography showed no stenosis or obstruction. Catecholamine was given for 1 day(Case 1) and for about 2 weeks (Case 2). Pimobendane was given to Case 2. Ejection fraction was 57% in Case 1 (2nd hospital day) and 33% (6th hospital day), 43% (7th hospital day)and 58% (16th hospital day)in Case 2. The recovery period of left ventricular abnormal wall motion and the medication period were longer in Case 2 showing diffuse hypokinesis than in Case 1 showing takotsubo-like cardiomyopathy. PMID:16764331

  9. Abdominal Aortic Intimal Flap Motion Characterization in Acute Aortic Dissection: Assessed with Retrospective ECG-Gated Thoracoabdominal Aorta Dual-Source CT Angiography

    PubMed Central

    Yang, Shifeng; Li, Xia; Chao, Baoting; Wu, Lebin; Cheng, Zhaoping; Duan, Yanhua; Wu, Dawei; Zhan, Yiqiang; Chen, Jiuhong; Liu, Bo; Ji, Xiaopeng; Nie, Pei; Wang, Ximing

    2014-01-01

    Objectives To evaluate the feasibility of dose-modulated retrospective ECG-gated thoracoabdominal aorta CT angiography (CTA) assessing abdominal aortic intimal flap motion and investigate the motion characteristics of intimal flap in acute aortic dissection (AAD). Materials and Methods 49 patients who had thoracoabdominal aorta retrospective ECG-gated CTA scan were enrolled. 20 datasets were reconstructed in 5% steps between 0 and 95% of the R-R interval in each case. The aortic intimal flap motion was assessed by measuring the short axis diameters of the true lumen and false lumen 2 cm above of celiac trunk ostium in different R-R intervals. Intimal flap motion and configuration was assessed by two independent observers. Results In these 49 patients, 37 had AAD, 7 had intramural hematoma, and 5 had negative result for acute aortic disorder. 620 datasets of 31 patients who showed double lumens in abdominal aorta were enrolled in evaluating intimal flap motion. The maximum and minimum true lumen diameter were 12.2±4.1 mm (range 2.6∼17.4) and 6.7±4.1 mm (range 0∼15.3) respectively. The range of intimal flap motion in all patients was 5.5±2.6 mm (range 1.8∼10.2). The extent of maximum true lumen diameter decreased during a cardiac cycle was 49.5%±23.5% (range 12%∼100%). The maximum motion phase of true lumen diameter was in systolic phase (5%∼40% of R-R interval). Maximum and minimum intimal flap motion was at 15% and 75% of the R-R interval respectively. Intimal flap configuration had correlation with the phase of cardiac cycle. Conclusions Abdominal intimal flap position and configuration varied greatly during a cardiac cycle. Retrospective ECG-gated thoracoabdominal aorta CTA can reflect the actual status of the true lumen and provide more information about true lumen collapse. This information may be helpful to diagnosis and differential diagnosis of dynamic abstraction. PMID:24503676

  10. Recurrence of Brenner ovary borderline tumor in the abdominal wall postoperative scar--a case report and research of the literature.

    PubMed

    Klasa, Lukasz; Wydra, Dariusz; Biernat, Wojciech

    2014-11-01

    We report a case of a 74-year-old female, who underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy due to a solid-cystic tumor of the right ovary. The histopathological diagnosis revealed a borderline Brenner tumor (BBT). After 25 disease-free months the patient was admitted to a hospital because of a tumor in the postoperative scar of the abdominal wall, later diagnosed as infiltrating Brenner tumor consistent with ovarian borderline lesion. The tumor in the postoperative scar was therefore diagnosed as BBT. The article presents results of literature search on BBT in order to find characteristic features of this very rare ovarian tumor. To the best of our knowledge, this is the first report of subcutaneous recurrence of Brenner ovary tumor of low malignant potential. PMID:25675807

  11. Necrotizing fasciitis: literature review of contemporary strategies for diagnosing and management with three case reports: torso, abdominal wall, upper and lower limbs

    PubMed Central

    2011-01-01

    Necrotizing fasciitis (NF) is an uncommon soft tissue infection, usually caused by toxin-producing virulent bacteria. It is characterized by widespread fascial necrosis primarily caused by Streptococcus hemolyticus. Shortly after the onset of the disease, patients become colonized with their own aerobic and anaerobic microflora from the gastrointestinal and/or urogenital tracts. Early diagnosis with aggressive multidisciplinary treatment is mandatory. We describe three clinical cases with NF. The first is a 69 years old man with diabetes mellitus type II, who presented with NF on the posterior chest wall, shoulder and arm. He was admitted to the intensive care unit (ICU) with a clinical picture of severe sepsis. Outpatient treatment and early surgical debridement of the affected zones (inside 3 hours after admittance) and critical care therapy were performed. The second case is of a 63 years old paraplegic man with diabetes mellitus type I. Pressure sores and perineal abscesses progressed to Fournier's gangrene of the perineum and scrotum. He had NF of the anterior abdominal wall and the right thigh. Outpatient treatment and early surgical debridement of the affected zones (inside 6 hour after admittance) and critical care therapy were performed. The third patient was a 56 year old man who had NF of the anterior abdominal wall, flank and retroperitoneal space. He had an operation of the direct inguinal hernia, which was complicated with a bowel perforation and secondary peritonitis. After establishing the diagnosis of NF of the abdominal wall and retroperitoneal space (RS), he was transferred to the ICU. There he first received intensive care therapy, after which emergency surgical debridement of the abdominal wall, left colectomy, and extensive debridement of the RS were done (72 hours after operation of inquinal hernia). On average, 4 serial debridements were performed in each patient. The median of serial debridement in all three cases was four times. Other

  12. Necrotizing fasciitis: literature review of contemporary strategies for diagnosing and management with three case reports: torso, abdominal wall, upper and lower limbs.

    PubMed

    Roje, Zdravko; Roje, Zeljka; Matić, Dario; Librenjak, Davor; Dokuzović, Stjepan; Varvodić, Josip

    2011-01-01

    Necrotizing fasciitis (NF) is an uncommon soft tissue infection, usually caused by toxin-producing virulent bacteria. It is characterized by widespread fascial necrosis primarily caused by Streptococcus hemolyticus. Shortly after the onset of the disease, patients become colonized with their own aerobic and anaerobic microflora from the gastrointestinal and/or urogenital tracts. Early diagnosis with aggressive multidisciplinary treatment is mandatory. We describe three clinical cases with NF. The first is a 69 years old man with diabetes mellitus type II, who presented with NF on the posterior chest wall, shoulder and arm. He was admitted to the intensive care unit (ICU) with a clinical picture of severe sepsis. Outpatient treatment and early surgical debridement of the affected zones (inside 3 hours after admittance) and critical care therapy were performed. The second case is of a 63 years old paraplegic man with diabetes mellitus type I. Pressure sores and perineal abscesses progressed to Fournier's gangrene of the perineum and scrotum. He had NF of the anterior abdominal wall and the right thigh. Outpatient treatment and early surgical debridement of the affected zones (inside 6 hour after admittance) and critical care therapy were performed. The third patient was a 56 year old man who had NF of the anterior abdominal wall, flank and retroperitoneal space. He had an operation of the direct inguinal hernia, which was complicated with a bowel perforation and secondary peritonitis. After establishing the diagnosis of NF of the abdominal wall and retroperitoneal space (RS), he was transferred to the ICU. There he first received intensive care therapy, after which emergency surgical debridement of the abdominal wall, left colectomy, and extensive debridement of the RS were done (72 hours after operation of inquinal hernia). On average, 4 serial debridements were performed in each patient. The median of serial debridement in all three cases was four times. Other

  13. Interventional heart wall motion analysis with cardiac C-arm CT systems

    NASA Astrophysics Data System (ADS)

    Müller, Kerstin; Maier, Andreas K.; Zheng, Yefeng; Wang, Yang; Lauritsch, Günter; Schwemmer, Chris; Rohkohl, Christopher; Hornegger, Joachim; Fahrig, Rebecca

    2014-05-01

    Today, quantitative analysis of three-dimensional (3D) dynamics of the left ventricle (LV) cannot be performed directly in the catheter lab using a current angiographic C-arm system, which is the workhorse imaging modality for cardiac interventions. Therefore, myocardial wall analysis is completely based on the 2D angiographic images or pre-interventional 3D/4D imaging. In this paper, we present a complete framework to study the ventricular wall motion in 4D (3D+t) directly in the catheter lab. From the acquired 2D projection images, a dynamic 3D surface model of the LV is generated, which is then used to detect ventricular dyssynchrony. Different quantitative features to evaluate LV dynamics known from other modalities (ultrasound, magnetic resonance imaging) are transferred to the C-arm CT data. We use the ejection fraction, the systolic dyssynchrony index a 3D fractional shortening and the phase to maximal contraction (ϕi, max) to determine an indicator of LV dyssynchrony and to discriminate regionally pathological from normal myocardium. The proposed analysis tool was evaluated on simulated phantom LV data with and without pathological wall dysfunctions. The LV data used is publicly available online at https://conrad.stanford.edu/data/heart. In addition, the presented framework was tested on eight clinical patient data sets. The first clinical results demonstrate promising performance of the proposed analysis tool and encourage the application of the presented framework to a larger study in clinical practice.

  14. Color structured light system of chest wall motion measurement for respiratory volume evaluation

    NASA Astrophysics Data System (ADS)

    Chen, Huijun; Cheng, Yuan; Liu, Dongdong; Zhang, Xiaodong; Zhang, Jue; Que, Chengli; Wang, Guangfa; Fang, Jing

    2010-03-01

    We present a structured light system to dynamically measure human chest wall motion for respiratory volume estimation. Based on a projection of an encoded color pattern and a few active markers attached to the trunk, respiratory volumes are obtained by evaluating the 3-D topographic changes of the chest wall in an anatomically consistent measuring region during respiration. Three measuring setups are established: a single-sided illuminating-recording setup for standing posture, an inclined single-sided setup for supine posture, and a double-sided setup for standing posture. Results are compared with the pneumotachography and show good agreement in volume estimations [correlation coefficient: R>0.99 (P<0.001) for all setups]. The isovolume tests present small variations of the obtained volume during the isovolume maneuver (standard deviation<0.085 L for all setups). After validation by the isovolume test, an investigation of a patient with pleural effusion using the proposed method shows pulmonary functional differences between the diseased and the contralateral sides of the thorax, and subsequent improvement of this imbalance after drainage. These results demonstrate the proposed optical method is capable of not only whole respiratory volume evaluation with high accuracy, but also regional pulmonary function assessment in different chest wall behaviors, with the advantage of whole-field measurement.

  15. Does mechanical massage of the abdominal wall after colectomy reduce postoperative pain and shorten the duration of ileus? Results of a randomized study.

    PubMed

    Le Blanc-Louvry, Isabelle; Costaglioli, Bruno; Boulon, Catherine; Leroi, Anne-Marie; Ducrotte, Philippe

    2002-01-01

    The aim of this study was to determine the effectiveness of mechanical abdominal massage on postoperative pain and ileus after colectomy. We hypothesized that parietal abdominal stimulation could counteract induced pain and postoperative ileus, through common spinal-sensitive pathways, with nociceptive visceral messages. After preoperative randomization, 25 patients (age 52 +/- 5 years) underwent active mechanical massage by intermittent negative pressure on the abdominal wall resulting in aspiration (Cellu M50 device, LPG, Valence, France), and 25 patients (age 60 +/- 6 years) did not receive active mechanical massage (placebo group). Massage sessions began the first day after colectomy and were performed daily until the seventh postoperative day. In the active-massage group, amplitude and frequency were used, which have been shown to be effective in reducing muscular pain, whereas in the placebo group, ineffective parameters were used. Visual analogue scale (VAS) pain scores, doses of analgesics (propacetamol), and delay between surgery and the time to first passage of flatus were assessed. Types and dosages of the anesthetic drugs and the duration of the surgical procedure did not differ between groups. From the second and third postoperative days, respectively, VAS pain scores (P < 0.001) and doses of analgesics (P < 0.05) were significantly lower in patients receiving active massage compared to the placebo group. Time to first passage of flatus was also significantly shorter in the active-massage group (1.8 +/- 0.3 days vs. 3.6 +/- 0.4 days, P < 0.01). No adverse effects were observed. These results suggest that mechanical massage of the abdominal wall may decrease postoperative pain and ileus after colectomy. PMID:11986017

  16. Domain wall motion effect on the anelastic behavior in lead zirconate titanate piezoelectric ceramics

    NASA Astrophysics Data System (ADS)

    Bourim, El Mostafa; Tanaka, Hidehiko; Gabbay, Maurice; Fantozzi, Gilbert; Cheng, Bo Lin

    2002-05-01

    Three undoped lead zirconate titanate (PZT) ceramics were prepared with compositions close to the morphotropic phase boundary: Pb(Zr0.50Ti0.50)O3, Pb(Zr0.52Ti0.48)O3, and Pb(Zr0.54Ti0.46)O3. Internal friction Q-1 and shear modulus G were measured versus temperature from 20 °C to 500 °C. Experiments were performed on an inverted torsional pendulum at low frequencies (0.1, 0.3, and 1 Hz). The ferroelectric-paraelectric phase transition results in a peak (P1) of Q-1 correlated with a sharp minimum M1 of G. Moreover the Q-1(T) curves show two relaxation peaks called R1 and R2 respectively, correlated with two shear modulus anomalies called A1 and A2 on the G(T) curves. The main features of the transition P1 peak are studied, they suggest that its behavior is similar to the internal friction peaks associated with martensitic transformation. The relaxation peak, R1 and R2 are both attributed to motion of domain walls (DWs), and can be analyzed by thermal activated process described by Arrhenius law. The R2 peak is demonstrated to be due to the interaction of domain walls and oxygen vacancies because it depends on oxygen vacancy concentration and electrical polarization. However, the R1 peak is more complex; its height is found to be increased as stress amplitude and heating rate increase. It seems that the R1 peak is influenced by three mechanisms: (i) relaxation due to DW-point defects interaction, (ii) variation of domain wall density, and (iii) domain wall depinning from point defect clusters.

  17. Magnetic configuration of submicron-sized magnetic patterns in domain wall motion memory

    NASA Astrophysics Data System (ADS)

    Ohshima, Norikazu; Numata, Hideaki; Fukami, Shunsuke; Nagahara, Kiyokazu; Suzuki, Tetsuhiro; Ishiwata, Nobuyuki; Fukumoto, Keiki; Kinoshita, Toyohiko; Ono, Teruo

    2010-05-01

    We observed magnetic configuration and its change by external magnetic fields in submicron-sized U- and H-shaped NiFe patterns with an x-ray magnetic circular dichroism photoemission electron microscope. The microscope images showed the formation of a single domain wall (DW) with transverse structure at one corner of the U- and H-shaped patterns by applying the magnetic field from the oblique direction. By applying the magnetic field from the direction parallel to a horizontal bar in the patterns, the magnetic configuration in the U-shaped pattern was changed and four patterns were formed: (1) the DW moved from one trap site to another, (2) the DW moved beyond the trap site and formed a single domain, (3) the DW moved and stopped between the trap sites, and (4) the DW remained at the initial position. Only pattern (1) showed reversible DW motion, although pattern (2) was predominantly formed. In contrast, the magnetization configurations showed pattern (1), and reversible DW motion was observed for more than 80% of the H-shaped patterns. Micromagnetic simulation revealed that the DW in the U-shaped pattern was not sufficiently fixed at the corner and easily moved and vanished at the edge of the patterns because the magnetization in the two parallel bars rotated with a magnetic field. The DW was trapped with sufficient strength at the corner, and DW motion occurred only between the trap sites for the H-shaped patterns. The DW motion process was observed with an in situ magnetic field using the x-ray magnetic circular dichroism photoemission electron microscope and the process could be optimized by controlling the pattern shape.

  18. The stability of steady motion of magnetic domain wall: Role of higher-order spin-orbit torques

    SciTech Connect

    He, Peng-Bin Yan, Han; Cai, Meng-Qiu; Li, Zai-Dong

    2015-12-14

    The steady motion of magnetic domain wall driven by spin-orbit torques is investigated analytically in the heavy/ferromagnetic metal nanowires for three cases with a current transverse to the in-plane and perpendicular easy axis, and along the in-plane easy axis. By the stability analysis of Walker wall profile, we find that if including the higher-order spin-orbit torques, the Walker breakdown can be avoided in some parameter regions of spin-orbit torques with a current transverse to or along the in-plane easy axis. However, in the case of perpendicular anisotropy, even considering the higher-order spin-orbit torques, the velocity of domain wall cannot be efficiently enhanced by the current. Furthermore, the direction of wall motion is dependent on the configuration and chirality of domain wall with a current along the in-plane easy axis or transverse to the perpendicular one. Especially, the direction of motion can be controlled by the initial chirality of domain wall. So, if only involving the spin-orbit mechanism, it is preferable to adopt the scheme of a current along the in-plane easy axis for enhancing the velocity and controlling the direction of domain wall.

  19. The stability of steady motion of magnetic domain wall: Role of higher-order spin-orbit torques

    NASA Astrophysics Data System (ADS)

    He, Peng-Bin; Yan, Han; Cai, Meng-Qiu; Li, Zai-Dong

    2015-12-01

    The steady motion of magnetic domain wall driven by spin-orbit torques is investigated analytically in the heavy/ferromagnetic metal nanowires for three cases with a current transverse to the in-plane and perpendicular easy axis, and along the in-plane easy axis. By the stability analysis of Walker wall profile, we find that if including the higher-order spin-orbit torques, the Walker breakdown can be avoided in some parameter regions of spin-orbit torques with a current transverse to or along the in-plane easy axis. However, in the case of perpendicular anisotropy, even considering the higher-order spin-orbit torques, the velocity of domain wall cannot be efficiently enhanced by the current. Furthermore, the direction of wall motion is dependent on the configuration and chirality of domain wall with a current along the in-plane easy axis or transverse to the perpendicular one. Especially, the direction of motion can be controlled by the initial chirality of domain wall. So, if only involving the spin-orbit mechanism, it is preferable to adopt the scheme of a current along the in-plane easy axis for enhancing the velocity and controlling the direction of domain wall.

  20. Effects of nitroglycerin, postextrasystolic potentiation, and pacing-induced ischaemia on wall motion in patients with ischaemic heart disease.

    PubMed Central

    Schwartz, F; Ensslen, R; Thormann, J; Sesto, M

    1977-01-01

    The influence of nitroglycerin, postextrasystolic potentiation, and rapid ventricular pacing on total and regional ventricular function was studied in 32 patients with normal ventricular function and in 44 patients with left ventricular asynergy caused by obstructive coronary artery disease. Total ventricular function was assessed by ventriculography and regional ventricular function was analysed by use of 7 hemiaxes. Nitroglycerin increased ejection fraction and decreased left ventricular systolic and end-diastolic pressures in the normally functioning ventricles; apical wall motion increased, while basal wall motion remained unchanged after nitroglycerin in these ventricles. Pressures fell significantly in ventricles with asynergy after nitroglycerin; ejection fraction decreased while wall motion in asynergic areas was inconsistently influenced. Postextrasystolic potentiation augmented ejection fraction by a powerful and homogeneous increase of wall motion in normally functioning ventricles. Asynergic areas and normal areas in diseased ventricles showed identical augmentation of wall motion after a premature beat. Rapid venticular pacing produced a significant increase in end-diastolic pressure and a fall in ejection fraction in patients with obstructive coronary artery disease. Wall motion in normal areas perfused by arteries with critical stenoses was dramatically depressed after pacing, while asynergic areas and normal areas perfused by normal arteries remained unchanged. The results show that normal contractile behaviour can be detected by postextrasystolic potentiation in asynergic areas, suggesting that some normally perfused muscle exists in these areas. Pacing stress does not further deteriorate function in asynergic areas, which suggests the presence of viable and well perfused muscle (within scar tissue) whose function may not profit from revascularization. Pacing-induced asynergy identifies the functional significance of coronary stenoses and suggests

  1. Easy moment direction and antiferromagnetic domain wall motion in Mn2Au

    NASA Astrophysics Data System (ADS)

    Barthem, Vitoria M. T. S.; Colin, Claire V.; Haettel, Richard; Dufeu, Didier; Givord, Dominique

    2016-05-01

    The interest of giving active functions to antiferromagnetic (AFM) materials in spintronics devices has been realized recently. Mn2Au is a high-Néel temperature antiferromagnet with large Mn moment, lying in plane of the tetragonal structure. To determine the direction of the moments in Mn2Au, an original approach is demonstrated, which should be generic to planar AFM materials. It involves the rotation of the granular sample around an axis perpendicular to the applied magnetic field. The family of easy moment directions is <110>. For grains prevented from rotating, the dominant magnetization process is AFM domain wall motion. Textured Mn2Au nanoelements could be introduced in spintronics devices, in which the Mn moments would be switched under modest external excitation.

  2. Coercivity of domain wall motion in thin films of amorphous rare earth-transition metal alloys

    NASA Technical Reports Server (NTRS)

    Mansuripur, M.; Giles, R. C.; Patterson, G.

    1991-01-01

    Computer simulations of a two dimensional lattice of magnetic dipoles are performed on the Connection Machine. The lattice is a discrete model for thin films of amorphous rare-earth transition metal alloys, which have application as the storage media in erasable optical data storage systems. In these simulations, the dipoles follow the dynamic Landau-Lifshitz-Gilbert equation under the influence of an effective field arising from local anisotropy, near-neighbor exchange, classical dipole-dipole interactions, and an externally applied field. Various sources of coercivity, such as defects and/or inhomogeneities in the lattice, are introduced and the subsequent motion of domain walls in response to external fields is investigated.

  3. Digital subtraction angiography in the evaluation of left ventricular function and wall motion in man.

    PubMed

    O'Connor, M K; Quigley, P J; Gearty, G F

    1984-08-01

    The purpose of this study was to examine the usefulness of digital subtraction angiography in the evaluation of left ventricular function (LVF). LVF was examined in 24 patients by three methods, (a) conventional ventriculography using an intraventricular injection (CLV) of 40 ml of contrast medium, (b) small volume (10-15 ml) left ventriculogram (SVLV) and (c) intravenous injection of 30 ml contrast medium (IVLV). Images were recorded via a conventional image intensifier--TV chain on to video tape and later analysed using a nuclear medicine computer with a digital interface. There was excellent correlation of ejection fraction and wall motion abnormalities between CLV and SVLV methods (r = 0.92 and r = 0.71, respectively) and good correlation between CLV and IVLV methods (r = 0.88 and r = 0.67, respectively). However, only minimal contrast induced premature ventricular contractions were observed in either the SVLV or IVLV methods compared with approximately 60% in the CLV method. Exclusion of studies containing ectopic cardiac cycles considerably improved the correlation between CLV and SVLV (r = 0.97) and between CLV and IVLV methods (r = 0.95). In conclusion, our results indicate that conventional left ventriculography may be replaced by either intravenous or small volume intraventricular methods with little loss of wall motion definition or error in ejection fraction estimation. The less invasive nature of the SVLV and IVLV methods should increase the usefulness of left ventriculography and extend its application to the assessment of left ventricular reserve under stress and during drug intervention. PMID:6207025

  4. Creep and Flow Regimes of Magnetic Domain-Wall Motion in Ultrathin Pt/Co/Pt Films with Perpendicular Anisotropy

    NASA Astrophysics Data System (ADS)

    Metaxas, P. J.; Jamet, J. P.; Mougin, A.; Cormier, M.; Ferré, J.; Baltz, V.; Rodmacq, B.; Dieny, B.; Stamps, R. L.

    2007-11-01

    We report on magnetic domain-wall velocity measurements in ultrathin Pt/Co(0.5 0.8nm)/Pt films with perpendicular anisotropy over a large range of applied magnetic fields. The complete velocity-field characteristics are obtained, enabling an examination of the transition between thermally activated creep and viscous flow: motion regimes predicted from general theories for driven elastic interfaces in weakly disordered media. The dissipation limited flow regime is found to be consistent with precessional domain-wall motion, analysis of which yields values for the damping parameter, α.

  5. The use of dual vacuum stabilization device to reduce kidney motion for stereotactic radiotherapy planning.

    PubMed

    Pham, Daniel; Kron, Tomas; Styles, Colin; Whitaker, May; Bressel, Mathias; Foroudi, Farshad; Schneider, Michal; Devereux, Thomas; Dang, Kim; Siva, Shankar

    2015-04-01

    Abdominal stereotactic ablative body radiotherapy is aided by motion management strategies to ensure accurate dose delivery as targets such as the kidney are easily influenced by breathing motion. Commercial devices such as compression plates and dual vacuum technology have been demonstrated to reduce the motion of lung and liver tumors. The aim of this study was to evaluate the effectiveness of a dual vacuum system in reducing kidney motion as well to investigate any relationship between abdominal wall motions with kidney motion. Ten healthy volunteers were set up with and without vacuum compression (Elekta BodyFIX(TM)) to simulate free and dampened breathing. Ultrasound imaging was used to visualize kidney motion at the same time an abdominal surface marker was monitored using infrared imaging (Varian, Real Time Position Management). The resulting kidney and abdominal motion tracks were imported into motion analysis (Physmo(TM)) and custom built software (Matlab) to calculate amplitude of motion independent of shifting baselines. Thirty-four kidney datasets were available for analysis, with six datasets unable to be retrieved. With vacuum compression six out of nine participants showed a mean reduction of kidney motion ranging between 1.6 and 8 mm (p < 0.050). One participant showed an increase in motion of 8.2 mm (p < 0.001) with vacuum compression. Two participants showed no significant change (<1 mm) in kidney motion. No relationship was observed for abdominal wall motion and motion changes in the left kidney (r = 0.345, p = 0.402) or right kidney (r = 0.527, p = 0.145). Vacuum compression reduced kidney motion in the majority of participants; however larger breathing motion can also result from its use. No pattern emerged regarding which patients may benefit from vacuum immobilization as abdominal wall motion was not found to be an adequate surrogate for kidney motion. PMID:24502551

  6. Myocardial metabolism, perfusion, wall motion and electrical activity in Duchenne muscular dystrophy

    SciTech Connect

    Perloff, J.K.; Henze, E.; Schelbert, H.R.

    1982-01-01

    The cardiomyopathy of Duchenne's muscular dystrophy originates in the posterobasal left ventricle and extends chiefly to the contiguous lateral wall. Ultrastructural abnormalities in these regions precede connective tissue replacement. We postulated that a metabolic fault coincided with or antedated the subcellular abnormality. Accordingly, regional left ventricular metabolism, perfusion and wall motion were studied using positron computed tomography and metabolic isotopes supplemented by thallium perfusion scans, equilibrium radionuclide angiography and M-mode and two-dimensional echocardiography. To complete the assessment, electrocardiograms, vectorcardiograms, 24 hour taped electrocardiograms and chest x-rays were analyzed. Positron computed tomography utilizing F-18 2-fluoro 2-deoxyglucose (FDG) provided the first conclusive evidence supporting the hypothesis of a premorphologic regional metabolic fault. Thus, cardiac involvement in duchenne dystrophy emerges as a unique form of heart disease, genetically targeting specific regions of ventricular myocardium for initial metabolic and subcellular changes. Reported ultrastructural abnormalities of the impulse and conduction systems provide, at least in part, a basis for the clinically observed sinus node, intraatrial, internodal, AV nodal and infranodal disorders.

  7. Successful treatment of burn and visceral injury combined with full-thickness loss of the abdominal wall after blast injury.

    PubMed

    Başaran, Ozgür; Karaarslan, Pelin; Sakalloğlu, A Ebru; Kesik, Emine; Karakayalý, Hamdi; Haberal, Mehmet

    2006-01-01

    A 29-year-old man was admitted to our institution 10 days after he had undergone an urgent exploratory laparotomy at a local army hospital after a terrorist bombing attack. On admission, deep second-degree and third-degree burns involving 25% of the upper and lower extremities were present, together with a 25 x 10-cm abdominal full-thickness blast injury defect on the left side, an infected eviscerated midline incision, and a colostomy on the right side of the abdomen. The patient underwent a second laparotomy, at which time the intraabdominal abscess was drained, and the abdominal cavity was irrigated with saline. A jejunal perforation was found and sutured. The abdominal cavity was left open and covered with a Bogota bag for temporary closure. On postburn day 18, the patient underwent débridment and grafting of the third-degree burns to the left and right arm and right lower extremities. After several débridment sessions (postburn days 16, 18, 20, 22, and 24), an abdominal skin release and reapproximation were performed (postburn day 26). On postburn day 36, split-thickness skin grafts were placed directly on the granulated tissue of the intestines and on a defect in the left flank and iliac regions. Postoperatively, the patient did well. He was discharged on postburn day 78 with all wounds well healed. In our opinion, temporary closure followed by direct application of meshed split-thickness skin grafts to exposed abdominal viscera represents a simple method of reconstruction that can be safely performed, with minimal risk, on critically ill patients. PMID:16998411

  8. Thermal-induced domain wall motion of tip-inverted micro/nanodomains in near-stoichiometric LiNbO3 crystals

    NASA Astrophysics Data System (ADS)

    Liu, X. Y.; Kitamura, K.; Liu, Y. M.; Ohuchi, F. S.; Li, J. Y.

    2011-09-01

    Thermal-induced domain wall motion of tip-inverted micro/nanodomains in near-stoichiometric LiNbO3 single crystals was investigated using piezoresponse force microscopy (PFM). The domain wall motion was observed in PFM phase and amplitude images at room temperature after the sample was subjected to a thermal process at a heating temperature higher than 100 °C. In hexagonal domains with only y walls, predetermined nucleation with layer-by-layer growth is the main mechanism for the domain wall motion. In the domains composed of both x walls and y walls, the x walls are more mobile than the y walls, and the domain wall motion starts from the random nucleation of steps along the x walls that finally grow into y walls. The domain wall motion in the near-stoichiometric LiNbO3 crystal is attributed to the energy-preferable domain wall orientation, the pyroelectric effect, and the screening charge variation caused by the thermal process.

  9. Theory of domain wall motion mediated magnetoelectric effects in a multiferroic composite

    NASA Astrophysics Data System (ADS)

    Petrov, V. M.; Srinivasan, G.

    2014-10-01

    A model is discussed for magnetoelectric (ME) interactions originating from the motion of magnetic domain walls (DWs) in a multiferroic composite of orthoferrites RFeO3 (RFO) with magnetic stripe domains and a piezoelectric such as lead magnesium niobate-lead titanate (PMN-PT). The DWs in RFO can be set in motion with an ac magnetic field up to a critical speed of 20 km/s, the highest for any magnetic system, leading to the excitation of bulk and shear magnetoacoustic waves. Thus, the ME coupling will arise from flexural deformation associated with DW motion (rather than the Joule magnetostriction mediated coupling under a static or quasistatic condition). A c plane orthoferrite with a single Néel-type DW in the bc plane and an ac magnetic field H along the c axis is assumed. The deflection in the bilayer due to DW motion is obtained when the DW velocity is a linear function H and the resulting induced voltage across PMN-PT is estimated. It is shown that a combination of spatial and time harmonics of the bending deformation leads to (i) a linear ME coefficient defined by αE=E/H and (ii) a quadratic ME coefficient αEQ=E/H2. The model is applied to yttrium orthoferrites (YFO) and a PMN-PT bilayer since YFO has one of the highest DW mobility amongst the orthoferrites. The coefficient αE is dependent on the DW position, and it is maximum when the DW equilibrium position is at the center of the sample. In YFO/PMN-PT the estimated low-frequency αE ˜ 30 mV/cm Oe and resonance value is 1.5 V/(cm Oe). Since orthoferrites (and PMN-PT) are transparent in the visible region and have a large Faraday rotation, the DW dynamics and the ME coupling could be studied simultaneously. The theory discussed here is of interest for studies on ME coupling and for applications such as magnetically controlled electro-optic devices.

  10. High speed domain wall motion in MgO-based magnetic tunnel junctions driven by perpendicular current injection

    NASA Astrophysics Data System (ADS)

    Metaxas, P. J.; Chanthbouala, A.; Matsumoto, R.; Cros, V.; Anane, A.; Grollier, J.; Fert, A.; Zvezdin, K. A.; Fukushima, A.; Yuasa, S.

    2012-02-01

    The ability to efficiently drive fast domain wall (DW) motion will pave the way for revolutionary new electronic devices ranging from DW-MRAMs to spintronic memristors. The majority of domain wall devices use a lateral, current-in-plane configuration in which critical current densities for domain wall motion remain quite high, typically being on the order of 100 MA/cm^2 with velocities generally limited to about 100 m/s. In this contribution we show that critical current densities can be decreased by up to two orders of magnitude using the current-perpendicular-to-plane geometry. Indeed, we demonstrate that a DW can be propagated back and forth along the free layer of a MgO-based magnetic tunnel junction (MTJ) in the absence of an external magnetic field using current densities that are on the order of 5 MA/cm^2. More notably however, we obtain high domain wall velocities for these low current densities: the MTJ's large resistance variations allow us to carry out time-resolved measurements of the wall motion from which we evidence DW velocities exceeding 500m/s.

  11. Enhancement of spin Hall effect induced torques for current-driven magnetic domain wall motion: Inner interface effect

    NASA Astrophysics Data System (ADS)

    Bang, Do; Yu, Jiawei; Qiu, Xuepeng; Wang, Yi; Awano, Hiroyuki; Manchon, Aurelien; Yang, Hyunsoo

    2016-05-01

    We investigate the current-induced domain wall motion in perpendicular magnetized Tb/Co wires with structure inversion asymmetry and different layered structures. We find that the critical current density to drive domain wall motion strongly depends on the layered structure. The lowest critical current density ˜15 MA /c m2 and the highest slope of domain wall velocity curve are obtained for the wire having thin Co sublayers and more inner Tb/Co interfaces, while the largest critical current density ˜26 MA /c m2 required to drive domain walls is observed in the Tb-Co alloy magnetic wire. It is found that the Co/Tb interface contributes negligibly to Dzyaloshinskii-Moriya interaction, while the effective spin-orbit torque strongly depends on the number of Tb/Co inner interfaces (n ). An enhancement of the antidamping torques by extrinsic spin Hall effect due to Tb rare-earth impurity-induced skew scattering is suggested to explain the high efficiency of current-induced domain wall motion.

  12. Modified hemi-double-stapling technique combined with the temporal abdominal-wall-lift method for performing Billroth I anastomosis after laparoscopically assisted distal gastrectomy.

    PubMed

    Fujii, Hidenori; Aotake, Toshiharu; Kawakami, Yoshiyuki; Okuda, Yukihiro; Doi, Koji; Hirose, Yuki; Matsushita, Toshio

    2008-12-01

    The authors have used a modified hemi-double-stapling (HDS) technique for reconstruction after laparoscopically assisted distal gastrectomy. The stomach is resected from the greater curvature side using a linear stapler inserted into the stomach from that side at a position vertical to the line of the greater curvature. Resection of the stomach is performed by extending the resection line to the lesser curvature using laparoscopic coagulating shears. The resected specimen is examined. After placement of a purse-string suture at the duodenal stump, an anvil is inserted into the stump, and an additional suture with 2-0 silk is placed over the purse-string suture. A curved intraluminal stapler (CDH25) is inserted into the stomach through the opening made on the lesser curvature side, and the center rod of the stapler is passed through the gastric wall on the corner of the resection line at the greater curvature. Ligation with 2-0 silk is added to the center rod by suturing the gastric tissue 5-8 mm from the center rod to encircle it. The authors call this the "one-knot setup HDS," and with this method, a large-caliber anastomosis is secured. In many cases, it is difficult to observe the anastomotic site through the small incisional opening. However, under laparoscopy with the temporal abdominal wall-lift method using the Multi Flap Gate, the anastomotic site can be easily and safely observed. One-knot setup HDS combined with the temporal abdominal wall-lift method is considered a safe and simple method for performing Billroth I anastomosis in laparoscopic distal gastrectomy. PMID:18324439

  13. Thermodynamic theory for thermally driven domain wall motion in magnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Wang, Xiang Rong

    2015-03-01

    It is well-established now that a thermal gradient can be used to manipulate spins in a magnetic texture like skyrmions and domain walls (DWs). A thermal gradient can interact with spins through different channels. For example, a thermal gradient can affect spins through the thermoelectric effects by which spin polarized electric current is generated in a ferromagnetic metal. In turn, the thermally generated electric current can interact with magnetic texture via spin-transfer torque (STT). A thermal gradient can also generate magnons or spin waves that interact with magnetic textures. This effect should be important in a ferromagnetic insulator. Spin waves (or magnons) interact with magnetic domain walls (DWs) in a complicated way that a DW can propagate either along or against magnon flow, similar to its electron counterpart. Probably differ from its electron counterpart where one may attribute the ``wrong'' DW propagation direction to the Dzyaloshinskii-Moriya interaction and various types of torques due to spin-orbit interactions, it will be very difficult to understand why a DW can move along the magnon flow if the angular momentum transfer is the only mechanism behind the magnon driven DW motion. It will also be difficulty to explain why ``wrong'' DW propagation direction has not been observed in thermally driven DW motion in both simulations and experiments. Thus, there must be other interaction(s) between spin waves and magnetic textures. In terms of thermal gradient driven DW propagation along a nanowire, a DW always propagates to the hot region of a magnetic insulator wire. We theoretically illustrate why it is surely so from thermodynamic viewpoint. It is shown that DW entropy is always larger than that of a domain. Equivalently, the free energy difference of a DW and a domain decreases as the temperature increases. The larger DW entropy is related to the increase of magnon density of states at low energy originated from the gapless bound spin waves in

  14. Soliton-like magnetic domain wall motion induced by the interfacial Dzyaloshinskii-Moriya interaction

    NASA Astrophysics Data System (ADS)

    Ono, Teruo

    Topological defects such as magnetic solitons, vortices, Bloch lines, and skyrmions start to play an important role in modern magnetism due to their extraordinary stability which can be hailed as future memory devices. Recently, novel type of antisymmetric exchange interaction, namely the Dzyaloshinskii-Moriya interaction (DMI), has been uncovered and found to influence on the formation of topological defects. Exploring how the DMI affects the dynamics of topological defects is therefore an important task. Here we investigate the dynamics of the magnetic domain wall (DW) under a DMI by developing a time-of-flight measurement scheme which allows us to measure the DW velocity for magnetic fields up to 0.3T. For a weak DMI, the trend of DW velocity follows the Walker's model which predicts that the velocity of DW increases with field up to a threshold (Walker field) and decreases abruptly. On the other hand, for a strong DMI, velocity breakdown is completely suppressed and the DW keeps its maximum velocity even far above the Walker field. Such a distinct trend of the DW velocity, which has never been predicted, can be explained in terms of magnetic soliton, of which topology can be protected by the DMI. Importantly, such a soliton-like DW motion is only observed in two dimensional systems, implying that the vertical Bloch lines (VBLs) creating inside of the magnetic domain-wall play a crucial role. This work was partly supported by JSPS KAKENHI Grant Numbers 15H05702, 26870300, 26870304, 26103002, 25.4251, Collaborative Research Program of the Institute for Chemical Research, Kyoto University, and R & D Project for ICT Key Technology of MEXT from the Japan Society for the Promotion of Science (JSPS).

  15. Abdominal Compartment Hypertension and Abdominal Compartment Syndrome.

    PubMed

    Maluso, Patrick; Olson, Jody; Sarani, Babak

    2016-04-01

    Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare but potentially morbid diagnoses. Clinical index of suspicion for these disorders should be raised following massive resuscitation, abdominal wall reconstruction/injury, and in those with space-occupying disorders in the abdomen. Gold standard for diagnosis involves measurement of bladder pressure, with a pressure greater than 12 mm Hg being consistent with IAH and greater than 25 mm Hg being consistent with ACS. Decompressive laparotomy is definitive therapy but paracentesis can be equally therapeutic in properly selected patients. Left untreated, ACS can lead to multisystem organ failure and death. PMID:27016163

  16. Use of /sup 1/H NMR to study molecular motion in cellulose, pectin, and bean cell walls

    SciTech Connect

    Taylor, I.E.P.; Tepfer, M.; Callaghan, P.T.; MacKay, A.L.; Bloom, M.

    1983-01-01

    Growing plant cells are enclosed in a framework, the cell wall, whose rigidity must be overcome for cell enlargement to occur. It has been shown that one of the primary modes of action of plant growth substances is to induce cell wall loosening. The mechansim of cell wall loosening is very poorly understood and may involve large-scale changes in the molecular mobility of the cell wall polysaccharides. Proton magnetic resonance (/sup 1/H NMR) was used to study molecular motion in bean stem cell walls as well as in cellulose, sodium pectate solutions, and calcium pectate gels. All samples were prepared in K/sub 2/O to minimize the contribution of water to the observed signals. The different NMR properties that have been measured are sensitive to molecular motions over a wide range of frequencies (10 kHz-90 MHz). For each sample, a free induction decay was obtained and the second moment as well as spin-lattice (longitudinal), spin-spin (transverse), and dipolar relaxations were measured. As expected, the different samples studied had strikingly different NMR properties. These results have been extended to look for pH-sensitive changes in the NMR properties of calcium pectate gels and bean cell walls, since both show marked pH-sensitive changes in their rheological behavior. Pulsed field gradient NMR studies of very mobile components of polysaccharide systems are discussed.

  17. Predicting the response of small-scale near-wall turbulence to large-scale outer motions

    NASA Astrophysics Data System (ADS)

    Agostini, Lionel; Leschziner, Michael

    2016-01-01

    A phenomenological model is provided, based on post-processing Direct Numerical Simulation (DNS) data at Reτ = 1020, which permits the near-wall-turbulence statistics to be predicted from a "universal signal," free from the effects of large-scale motions, in combination with information on the large-scale motions in the outer log-law region. The separation of large-scale and small-scale motions is effected, unusually, by means of the "Empirical Mode Decomposition" method, without explicit wavelength cutoffs. The model first yields the universal field by removing, from a full-volume turbulence field at an arbitrary time level, the effects of large-scale convective displacements (footprints), the modulation of the small-scale motions, caused by the large-scale motions, and distortions arising from sweep-induced splatting. In contrast to other modelling efforts, the present framework extends to all three velocity components, as is demonstrated by reference to joint (u - v) and (u - w) probability-density functions (PDFs). The model is then successfully used to reconstitute the full near-wall statistics by combining the universal field with the outer large-scale motions at any time level other than that for which the universal field was determined.

  18. Quantitative Assessment of Regional Wall Motion Abnormalities Using Dual-Energy Digital Subtraction Intravenous Ventriculography

    NASA Astrophysics Data System (ADS)

    McCollough, Cynthia H.

    Healthy portions of the left ventricle (LV) can often compensate for regional dysfunction, thereby masking regional disease when global indices of LV function are employed. Thus, quantitation of regional function provides a more useful method of assessing LV function, especially in diseases that have regional effects such as coronary artery disease. This dissertation studied the ability of a phase -matched dual-energy digital subtraction angiography (DE -DSA) technique to quantitate changes in regional LV systolic volume. The potential benefits and a theoretical description of the DE imaging technique are detailed. A correlated noise reduction algorithm is also presented which raises the signal-to-noise ratio of DE images by a factor of 2 -4. Ten open-chest dogs were instrumented with transmural ultrasonic crystals to assess regional LV function in terms of systolic normalized-wall-thickening rate (NWTR) and percent-systolic-thickening (PST). A pneumatic occluder was placed on the left-anterior-descending (LAD) coronary artery to temporarily reduce myocardial blood flow, thereby changing regional LV function in the LAD bed. DE-DSA intravenous left ventriculograms were obtained at control and four levels of graded myocardial ischemia, as determined by reductions in PST. Phase-matched images displaying changes in systolic contractile function were created by subtracting an end-systolic (ES) control image from ES images acquired at each level of myocardial ischemia. The resulting wall-motion difference signal (WMD), which represents a change in regional systolic volume between the control and ischemic states, was quantitated by videodensitometry and compared with changes in NWTR and PST. Regression analysis of 56 data points from 10 animals shows a linear relationship between WMD and both NWTR and PST: WMD = -2.46 NWTR + 13.9, r = 0.64, p < 0.001; WMD = -2.11 PST + 18.4, r = 0.54, p < 0.001. Thus, changes in regional ES LV volume between rest and ischemic states, as

  19. Technical Note: Intrafractional changes in time lag relationship between anterior–posterior external and superior–inferior internal motion signals in abdominal tumor sites

    SciTech Connect

    Regmi, Rajesh; Lovelock, D. Michael; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D.; Mageras, Gig S.; Goodman, Karyn A.; Wu, Abraham J.

    2015-06-15

    Purpose: To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. Methods: Six gastroesophageal junction and three pancreatic cancer patients (IRB-approved protocol) received two cone-beam CTs (CBCT), one before and one after treatment. Time between scans was less than 30 min. Each patient had at least one implanted fiducial marker near the tumor. In all scans, abdominal displacement (Varian RPM) was recorded as the external motion signal. Purpose-built software tracked fiducials, representing internal signal, in CBCT projection images. Time lag between superior–inferior (SI) internal and anterior–posterior external signals was found by maximizing the correlation coefficient in each breathing cycle and averaging over all cycles. Time-lag-induced discrepancy between internal SI position and that predicted from the external signal (external prediction error) was also calculated. Results: Mean ± standard deviation time lag, over all scans and patients, was 0.10 ± 0.07 s (range 0.01–0.36 s). External signal lagged the internal in 17/18 scans. Change in time lag between pre- and post-treatment CBCT was 0.06 ± 0.07 s (range 0.01–0.22 s), corresponding to 3.1% ± 3.7% (range 0.6%–10.8%) of gate width (range 1.6–3.1 s). In only one patient, change in time lag exceeded 10% of the gate width. External prediction error over all scans of all patients varied from 0.1 ± 0.1 to 1.6 ± 0.4 mm. Conclusions: Time lag between internal motion along SI and external signals is small compared to the treatment gate width of abdominal patients examined in this study. Change in time lag within a treatment session, inferred from pre- to post-treatment measurements is also small, suggesting that a single measurement of time lag at the session start is adequate. These findings require confirmation in a larger number of patients.

  20. Technical Note: Intrafractional changes in time lag relationship between anterior–posterior external and superior–inferior internal motion signals in abdominal tumor sites

    PubMed Central

    Regmi, Rajesh; Lovelock, D. Michael; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D.; Goodman, Karyn A.; Wu, Abraham J.; Mageras, Gig S.

    2015-01-01

    Purpose: To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. Methods: Six gastroesophageal junction and three pancreatic cancer patients (IRB-approved protocol) received two cone-beam CTs (CBCT), one before and one after treatment. Time between scans was less than 30 min. Each patient had at least one implanted fiducial marker near the tumor. In all scans, abdominal displacement (Varian RPM) was recorded as the external motion signal. Purpose-built software tracked fiducials, representing internal signal, in CBCT projection images. Time lag between superior–inferior (SI) internal and anterior–posterior external signals was found by maximizing the correlation coefficient in each breathing cycle and averaging over all cycles. Time-lag-induced discrepancy between internal SI position and that predicted from the external signal (external prediction error) was also calculated. Results: Mean ± standard deviation time lag, over all scans and patients, was 0.10 ± 0.07 s (range 0.01–0.36 s). External signal lagged the internal in 17/18 scans. Change in time lag between pre- and post-treatment CBCT was 0.06 ± 0.07 s (range 0.01–0.22 s), corresponding to 3.1% ± 3.7% (range 0.6%–10.8%) of gate width (range 1.6–3.1 s). In only one patient, change in time lag exceeded 10% of the gate width. External prediction error over all scans of all patients varied from 0.1 ± 0.1 to 1.6 ± 0.4 mm. Conclusions: Time lag between internal motion along SI and external signals is small compared to the treatment gate width of abdominal patients examined in this study. Change in time lag within a treatment session, inferred from pre- to post-treatment measurements is also small, suggesting that a single measurement of time lag at the session start is adequate. These findings require confirmation in a larger number of patients. PMID:26127033

  1. Soliton-like magnetic domain wall motion induced by the interfacial Dzyaloshinskii-Moriya interaction

    NASA Astrophysics Data System (ADS)

    Yoshimura, Yoko; Kim, Kab-Jin; Taniguchi, Takuya; Tono, Takayuki; Ueda, Kohei; Hiramatsu, Ryo; Moriyama, Takahiro; Yamada, Keisuke; Nakatani, Yoshinobu; Ono, Teruo

    2016-02-01

    Topological defects such as magnetic solitons, vortices and skyrmions have started to play an important role in modern magnetism because of their extraordinary stability, which can be exploited in the production of memory devices. Recently, a type of antisymmetric exchange interaction, namely the Dzyaloshinskii-Moriya interaction (DMI; refs ,), has been uncovered and found to influence the formation of topological defects. Exploring how the DMI affects the dynamics of topological defects is therefore an important task. Here we investigate the dynamics of the magnetic domain wall (DW) under a DMI by developing a real time DW detection scheme. For a weak DMI, the DW velocity increases with the external field and reaches a peak velocity at a threshold field, beyond which it abruptly decreases. For a strong DMI, on the other hand, the velocity reduction is completely suppressed and the peak velocity is maintained constant even far above the threshold field. Such a distinct trend of the velocity can be explained in terms of a magnetic soliton, the topology of which is protected during its motion. Our results therefore shed light on the physics of dynamic topological defects, which paves the way for future work in topology-based memory applications.

  2. Light effects in the atomic-motion-induced Ramsey narrowing of dark resonances in wall-coated cells

    SciTech Connect

    Breschi, E.; Schori, C.; Di Domenico, G.; Mileti, G.; Kazakov, G.; Litvinov, A.; Matisov, B.

    2010-12-15

    We report on light shift and broadening in the atomic-motion-induced Ramsey narrowing of dark resonances prepared in alkali-metal vapors contained in wall-coated cells without buffer gas. The atomic-motion-induced Ramsey narrowing is due to the free motion of the polarized atomic spins in and out of the optical interaction region before spin relaxation. As a consequence of this effect, we observe a narrowing of the dark resonance linewidth as well as a reduction of the ground states' light shift when the volume of the interaction region decreases at constant optical intensity. The results can be intuitively interpreted as a dilution of the intensity effect similar to a pulsed interrogation due to the atomic motion. Finally the influence of this effect on the performance of compact atomic clocks is discussed.

  3. The use of biomaterials in the repair of abdominal wall defects: a comparative study between polypropylene meshes (Marlex) and a new polytetrafluoroethylene prosthesis (Dual Mesh).

    PubMed

    Bellón, J M; Contreras, L A; Buján, J; Carrera-San Martín, A

    1997-10-01

    In this study we compared the behaviour of the non-porous on one side ePTFE Dual Mesh prosthesis and the macroporous polypropylene mesh Marlex in the repair of abdominal wall defects in rabbits. We evaluated the degree of integration with recipient tissue, biological tolerance, adhesion formation with viscera and the biomechanical resistance of the repair zone. Our results showed good biological tolerance of both prostheses and a high degree of adhesion formation in Marlex implants. In animals with Dual Mesh implants, only loose adhesions were seen. Marlex implants induced the presence of disorganized scar tissue, while the Dual Mesh prostheses were encapsulated by organized tissue. The macrophage response was similar in both decreasing with time. The resistance to traction was higher when the reparation was done with polypropylene. We concluded that the structure of the prosthesis determines its degree of integration and the resistance to traction of the repaired zone. PMID:9399138

  4. A cellular scale numerical study of the effect of mechanical properties of erythrocytes on the near-wall motion of platelets

    NASA Astrophysics Data System (ADS)

    Xu, Jing; Wang, Xiao-Long; Liu, Yun-Qiao; Gong, Xiao-Bo

    2014-04-01

    The effect of mechanical properties of erythrocytes on the near-wall motion of platelets was numerically studied with the immersed boundary method. Cells were modeled as viscous-fluid-filled capsules surrounded by hyper-elastic membranes with negligible thickness. The numerical results show that with the increase of hematocrit, the near-wall approaching of platelets is enhanced, with which platelets exhibit larger deformation and orientation angle of its near-wall tank-treading motion, and the lateral force pushing platelets to the wall is increased with larger fluctuation amplitude. Meanwhile the near-wall approaching is reduced by increasing the stiffness of erythrocytes. [Figure not available: see fulltext.

  5. Anomalous switching in Nb/Ru/Sr2RuO4 topological junctions by chiral domain wall motion

    NASA Astrophysics Data System (ADS)

    Anwar, M. S.; Nakamura, Taketomo; Yonezawa, S.; Yakabe, M.; Ishiguro, R.; Takayanagi, H.; Maeno, Y.

    2013-08-01

    A spontaneous symmetry breaking in a system often results in domain wall formation. The motion of such domain walls is utilized to realize novel devices like racetrack-memories, in which moving ferromagnetic domain walls store and carry information. Superconductors breaking time reversal symmetry can also form domains with degenerate chirality of their superconducting order parameter. Sr2RuO4 is the leading candidate of a chiral p-wave superconductor, expected to be accompanied by chiral domain structure. Here, we present that Nb/Ru/Sr2RuO4 topological superconducting-junctions, with which the phase winding of order parameter can be effectively probed by making use of real-space topology, exhibit unusual switching between higher and lower critical current states. This switching is well explained by chiral-domain-wall dynamics. The switching can be partly controlled by external parameters such as temperature, magnetic field and current. These results open up a possibility to utilize the superconducting chiral domain wall motion for future novel superconducting devices.

  6. Faster motion of double 360° domain walls system induced by spin-polarized current

    SciTech Connect

    Zhang, S. F.; Zhu, Q. Y.; Mu, C. P.; Zheng, Q.; Liu, X. Y.; Liu, Q. F.; Wang, J. B.

    2014-05-07

    By micromagnetic simulation, we investigated a double 360° domain walls system in two parallel nanowires. Two domain walls are coupled to each other via magnetostatic interaction. When a spin-polarized current is applied to only one nanowire or both nanowires with the same direction, the two domain walls propagate along nanowires together. The critical velocity of such system is obviously higher than that of a single 360° domain wall. The interaction between the two domain walls can be modeled as two bodies that connected by a spring, and we analyzed the coupling characteritics of the double 360° domain walls at last.

  7. Infarct-induced wall motion abnormalities in aortocoronary bypass patients: Correlation with electrocardiographic, enzymatic, and scintigraphic diagnostic criteria

    PubMed Central

    Depuey, E. Gordon; Mathur, Virendra; Hall, Robert J.; Burdine, John A.

    1980-01-01

    Gated isotope ventriculograms performed 7 to 12 days postoperatively in 50 aortocoronary bypass patients with perioperative myocardial infarction (POMI) were compared with preoperative contrast ventriculograms. The diagnosis of POMI was based on serial electrocardiograms (EKGs), cardiac enzyme studies, and 99mTc-pyrophosphate (PYP) scintigraphy. Seven patients exhibited no new regional wall motion abnormalities. Nine had new areas of localized hypokinesis. The remaining 34 demonstrated localized akinesis or dyskinesis; 12 of these also exhibited a greater than 20% decrease in ejection fraction. The severity of the postoperative wall motion abnormality was paralleled by the intensity of PYP accumulation but not necessarily by the degree of cardiac enzyme elevation. Because they occurred in only 62% of patients, new Q waves were considered an insensitive indicator of POMI. Our study revealed that POMI frequently produces significant changes in left ventricular kinetics. Of the standard techniques utilized, the PYP scan had the greatest predictive value. Images PMID:15216241

  8. SVM-based classification of LV wall motion in cardiac MRI with the assessment of STE

    NASA Astrophysics Data System (ADS)

    Mantilla, Juan; Garreau, Mireille; Bellanger, Jean-Jacques; Paredes, José Luis

    2015-01-01

    In this paper, we propose an automated method to classify normal/abnormal wall motion in Left Ventricle (LV) function in cardiac cine-Magnetic Resonance Imaging (MRI), taking as reference, strain information obtained from 2D Speckle Tracking Echocardiography (STE). Without the need of pre-processing and by exploiting all the images acquired during a cardiac cycle, spatio-temporal profiles are extracted from a subset of radial lines from the ventricle centroid to points outside the epicardial border. Classical Support Vector Machines (SVM) are used to classify features extracted from gray levels of the spatio-temporal profile as well as their representations in the Wavelet domain under the assumption that the data may be sparse in that domain. Based on information obtained from radial strain curves in 2D-STE studies, we label all the spatio-temporal profiles that belong to a particular segment as normal if the peak systolic radial strain curve of this segment presents normal kinesis, or abnormal if the peak systolic radial strain curve presents hypokinesis or akinesis. For this study, short-axis cine- MR images are collected from 9 patients with cardiac dyssynchrony for which we have the radial strain tracings at the mid-papilary muscle obtained by 2D STE; and from one control group formed by 9 healthy subjects. The best classification performance is obtained with the gray level information of the spatio-temporal profiles using a RBF kernel with 91.88% of accuracy, 92.75% of sensitivity and 91.52% of specificity.

  9. Evaluating MRI based vascular wall motion as a biomarker of Fontan hemodynamic performance

    NASA Astrophysics Data System (ADS)

    Menon, Prahlad G.; Hong, Haifa

    2015-03-01

    The Fontan procedure for single-ventricle heart disease involves creation of pathways to divert venous blood from the superior & inferior venacavae (SVC, IVC) directly into the pulmonary arteries (PA), bypassing the right ventricle. For optimal surgical outcomes, venous flow energy loss in the resulting vascular construction must be minimized and ensuring close to equal flow distribution from the Fontan conduit connecting IVC to the left & right PA is paramount. This requires patient-specific hemodynamic evaluation using computational fluid dynamics (CFD) simulations which are often time and resource intensive, limiting applicability for real-time patient management in the clinic. In this study, we report preliminary efforts at identifying a new non-invasive imaging based surrogate for CFD simulated hemodynamics. We establish correlations between computed hemodynamic criteria from CFD modeling and cumulative wall displacement characteristics of the Fontan conduit quantified from cine cardiovascular MRI segmentations over time (i.e. 20 cardiac phases gated from the start of ventricular systole), in 5 unique Fontan surgical connections. To focus our attention on diameter variations while discounting side-to-side swaying motion of the Fontan conduit, the difference between its instantaneous regional expansion and inward contraction (averaged across the conduit) was computed and analyzed. Maximum Fontan conduit-average expansion over the cardiac cycle correlated with the anatomy-specific diametric offset between the axis of the IVC and SVC (r2=0.13, p=0.55) - a known factor correlated with Fontan energy loss and IVC-to-PA flow distribution. Investigation in a larger study cohort is needed to establish stronger statistical correlations.

  10. Pre-ejectional left ventricular wall motions studied on conscious dogs using Doppler myocardial imaging: relationships with indices of left ventricular function.

    PubMed

    Pellerin, D; Berdeaux, A; Cohen, L; Giudicelli, J F; Witchitz, S; Veyrat, C

    1998-11-01

    Duration of the pre-ejection period is a sensitive index of myocardial function. Our purpose was to document normal pre-ejectional left ventricular (LV) wall motions at rest and under dobutamine using Doppler myocardial imaging (DMI), and to correlate posterior wall velocities with indices of LV systolic function. M-mode recordings of both walls were imaged on eight conscious dogs chronically instrumented. Subendocardial pre-ejectional velocities were digitized and measured every 3.8 ms. DMI analysis consisted of sign recognition, velocity measurement, duration and timing from the Q wave of the electrocardiogram. Isovolumic contraction time (Ict) was represented by the time interval from onset to peak of the first derivative of LV pressure. Conventional Doppler labelling of velocity signs, positive toward and negative away from the transducer, was applied to the direction of encoded wall motions. For physiological understanding, wall motions of both walls were also labelled inward and outward with respect to the left ventricular cavity center. In each wall, PEP was shown as several colored strips, each strip representing the period of time that the wall was moving in one direction. Changes in velocity sign corresponding to changes in direction of motion were opposed in each wall (p < 0.001), featuring successive inward and outward wall motions. There was a markedly sustained inward motion during Ict. Its velocity amplitude increased with dobutamine. There was a positive correlation between velocities of the inward motion contemporaneous of Ict and ejection fraction (r = 0.72, p < 0.003). Values of Ict respectively drawn from DMI and from hemodynamics were also significantly correlated (r = 0.85, p < 0.007). Thus, the inward motion evidenced by DMI during Ict appears promising to assess myocardial function and effect of drugs. PMID:10385949

  11. Abdominal Adhesions

    MedlinePlus

    ... Abdominal Adhesions 1 Ward BC, Panitch A. Abdominal adhesions: current and novel therapies. Journal of Surgical Research. 2011;165(1):91– ... are abdominal adhesions and intestinal obstructions ... generally do not require treatment. Surgery is the only way to treat abdominal ...

  12. Recurrent incisional hernia, enterocutaneous fistula and loss of the substance of the abdominal wall: plastic with organic prosthesis, skin graft and VAC therapy. Clinical case.

    PubMed

    Nicodemi, Sara; Corelli, Sergio; Sacchi, Marco; Ricciardi, Edoardo; Costantino, Annarita; Di Legge, Pietro; Ceci, Francesco; Cipriani, Benedetta; Martellucci, Annunziata; Santilli, Mario; Orsini, Silvia; Tudisco, Antonella; Stagnitti, Franco

    2015-01-01

    Surgical wounds dehiscence is a serious post-operatory complication, with an incidence between 0.4% and 3.5%. Mortality is more than 45%. Complex wounds treatment may require a multidisciplinary management. VAC Therapy could be an alternative treatment regarding complex wound. VAC therapy has been recently introduced on skin's graft tissue management reducing skin graft rejection. The use of biological prosthesis has been tested in a contaminated field, better than synthetic meshes, which often need to be removed. The Permacol is more resistant to degradation by proteases due to its cross-links. Surgery is still considered the best treatment for digestive fistula. A 58 years old obese woman come to our attention, she was operated for an abdominal hernia. She had a post-operatory entero-cutaneous fistula. She was submitted to bowel resection, the anastomosis has been tailored and the hernia of the abdominal wall has been repaired with biological mesh for managing such condition. She had a wound dehiscence with loss of substance and the exposure of the biological prosthesis, nearly 20 cm diameter. She was treated first with antibiotic therapy and simple medications. In addiction, antibiotic therapy was necessary late associated to 7 months with advanced medications allowed a small reduction's defect. Because of its, treatment went on for two more months using VAC therapy. Antibiotic's therapy was finally suspended. The VAC therapy allowed the reduction of the gap, between skin and subcutaneous tissue, and the defect's size preparing a suitable ground for the skin graft. The graft, managed with the vac therapy, was necessary to complete the healing process. PMID:25953007

  13. Open repair of large abdominal wall hernias with and without components separation; an analysis from the ACS-NSQIP database

    PubMed Central

    Desai, Nirav K.; Leitman, I. Michael; Mills, Christopher; Lavarias, Valentina; Lucido, David L.; Karpeh, Martin S.

    2016-01-01

    Background Components separation technique emerged several years ago as a novel procedure to improve durability of repair for ventral abdominal hernias. Almost twenty-five years since its initial description, little comprehensive risk adjusted data exists on the morbidity of this procedure. This study is the largest analysis to date of short-term outcomes for these cases. Methods The ACS-NSQIP database identified open ventral or incisional hernia repairs with components separation from 2005 to 2012. A data set of cohorts without this technique, matched for preoperative risk factors and operative characteristics, was developed for comparison. A comprehensive risk-adjusted analysis of outcomes and morbidity was performed. Results A total of 68,439 patients underwent open ventral hernia repair during the study period (2245 with components separation performed (3.3%) and 66,194 without). In comparison with risk-adjusted controls, use of components separation increased operative duration (additional 83 min), length of stay (6.4 days vs. 3.8 days, p < 0.001), return to the OR rate (5.9% vs. 3.6%, p < 0.001), and 30-day morbidity (10.1% vs. 7.6%, p < 0.001) with no increase in mortality (0.0% in each group). Conclusions Components separation technique for large incisional hernias significantly increases length of stay and postoperative morbidity. Novel strategies to improve short-term outcomes are needed with continued use of this technique. PMID:27158489

  14. Component separation in abdominal trauma.

    PubMed

    Rawstorne, Edward; Smart, Christopher J; Fallis, Simon A; Suggett, Nigel

    2014-01-01

    Component separation is established for complex hernia repairs. This case presents early component separation and release of the anterior and posterior sheath to facilitate closure of the abdominal wall following emergency laparotomy, reinforcing the repair with a biological mesh. On Day 11 following an emergency laparotomy for penetrating trauma, this patient underwent component separation and release of the anterior and posterior sheath. An intra-abdominal biological mesh was secured, and the fascia and skin closed successfully. Primary abdominal closure can be achieved in patients with penetrating abdominal trauma with the use of component separation and insertion of intra-abdominal biological mesh, where standard closure is not possible. PMID:24876334

  15. Remodeling characteristics and collagen distribution in synthetic mesh materials explanted from human subjects after abdominal wall reconstruction: an analysis of remodeling characteristics by patient risk factors and surgical site classifications

    PubMed Central

    Cavallo, Jaime A.; Roma, Andres A.; Jasielec, Mateusz S.; Ousley, Jenny; Creamer, Jennifer; Pichert, Matthew D.; Baalman, Sara; Frisella, Margaret M.; Matthews, Brent D.

    2014-01-01

    Background The purpose of this study was to evaluate the associations between patient characteristics or surgical site classifications and the histologic remodeling scores of synthetic meshes biopsied from their abdominal wall repair sites in the first attempt to generate a multivariable risk prediction model of non-constructive remodeling. Methods Biopsies of the synthetic meshes were obtained from the abdominal wall repair sites of 51 patients during a subsequent abdominal re-exploration. Biopsies were stained with hematoxylin and eosin, and evaluated according to a semi-quantitative scoring system for remodeling characteristics (cell infiltration, cell types, extracellular matrix deposition, inflammation, fibrous encapsulation, and neovascularization) and a mean composite score (CR). Biopsies were also stained with Sirius Red and Fast Green, and analyzed to determine the collagen I:III ratio. Based on univariate analyses between subject clinical characteristics or surgical site classification and the histologic remodeling scores, cohort variables were selected for multivariable regression models using a threshold p value of ≤0.200. Results The model selection process for the extracellular matrix score yielded two variables: subject age at time of mesh implantation, and mesh classification (c-statistic = 0.842). For CR score, the model selection process yielded two variables: subject age at time of mesh implantation and mesh classification (r2 = 0.464). The model selection process for the collagen III area yielded a model with two variables: subject body mass index at time of mesh explantation and pack-year history (r2 = 0.244). Conclusion Host characteristics and surgical site assessments may predict degree of remodeling for synthetic meshes used to reinforce abdominal wall repair sites. These preliminary results constitute the first steps in generating a risk prediction model that predicts the patients and clinical circumstances for which non

  16. Echocardiographic analysis of regional left ventricular wall motion in children after the arterial switch operation for complete transposition of the great arteries

    SciTech Connect

    Vogel, M.; Smallhorn, J.F.; Trusler, G.A.; Freedom, R.M. )

    1990-05-01

    Regional left ventricular wall motion was assessed by two-dimensional echocardiography in 21 patients with complete transposition of the great arteries at a mean of 2.2 years (range 0.3 to 7) after an arterial switch operation. Fourteen patients had undergone a two-stage and seven patients a primary repair. Twenty patients were found to have echocardiographic images adequate for wall motion analysis. The results of these studies were correlated with thallium-201 myocardial perfusion scans. Left ventricular wall motion was assessed by measuring regional area change in parasternal and apical views. After planimetry of an end-systolic and an end-diastolic frame, the ventricle was divided into eight equal segments and the percent area change was calculated. Both a fixed reference and a floating system correcting for translation and rotation were applied. The measurements in the patient group were compared with normal age-matched values previously obtained in 55 normal infants and children. Wall motion abnormalities, found in seven patients, were located at the apex in three, at the inferior septum and anterolateral wall in one and the inferior, anterolateral and lateral walls in one patient each. All had a myocardial perfusion defect in a corresponding anatomic location. One patient with a small reversible perfusion defect at the basilar septum had normal regional wall motion. The sensitivity of detecting impairment of myocardial perfusion was 0.95. Wall motion abnormalities were found only in patients who had undergone a two-stage repair. Echocardiographic wall motion analysis can be used as a screening method to identify patients with suspected myocardial ischemia after the arterial switch operation.

  17. Acute Beta Blockade at Peak Stress: Will It Alter the Sensitivity of Dobutamine Stress Echocardiography in Patients with Normal Resting Wall Motion?

    PubMed Central

    Abdel-Salam, Zainab; Ghazy, Mohamed; Khaled, Mohamed; Nammas, Wail

    2016-01-01

    Background We compared the accuracy of recovery phase images following administration of intravenous propranolol with peak stress images, for detection of coronary artery disease in patients with no resting wall motion abnormalities undergoing dobutamine stress echocardiography. Methods We enrolled 100 consecutive patients with no resting wall motion abnormalities who underwent dobutamine stress echocardiography. Propranolol was injected after termination of dobutamine infusion. Positive peak stress images were defined as the induction of wall motion abnormalities at any stage before propranolol injection. Positive recovery phase images were defined as maintenance or worsening of wall motion abnormalities induced at peak stress, or the appearance of new wall motion abnormalities during recovery phase. Significant coronary stenosis was defined as ≥ 50% obstruction of ≥ 1 sizable artery by coronary angiography. Results Seventy-two patients (72%) had significant coronary artery disease. Analysis of peak stress images revealed sensitivity, specificity, positive and negative predictive values of 80.6%, 85.7%, 93.5%, and 63.2%; the overall accuracy was 82%. Analysis of the recovery phase images revealed sensitivity, specificity, positive and negative predictive values of 91.7%, 75%, 90.4%, and 77.8%; here, the overall accuracy was 87%. Conclusions In patients with no resting wall motion abnormalities, acute beta blockade during dobutamine stress echocardiography improved the sensitivity of recovery phase images for detection of significant coronary artery disease versus peak stress images, but with reduced specificity. PMID:27122936

  18. Harmonic Motion Imaging for Abdominal Tumor Detection and High-intensity Focused Ultrasound Ablation Monitoring: A Feasibility Study in a Transgenic Mouse Model of Pancreatic Cancer

    PubMed Central

    Chen, Hong; Hou, Gary Y.; Han, Yang; Payen, Thomas; Palermo, Carmine F.; Olive, Kenneth P.; Konofagou, Elisa E.

    2015-01-01

    Harmonic motion imaging (HMI) is a radiation force-based elasticity imaging technique that tracks oscillatory tissue displacements induced by sinusoidal ultrasonic radiation force to assess relative tissue stiffness. The objective of this study was to evaluate the feasibility of HMI in pancreatic tumor detection and high-intensity focused ultrasound (HIFU) treatment monitoring. The HMI system consisted of a focused ultrasound transducer, which generated sinusoidal radiation force to induce oscillatory tissue motion at 50 Hz, and a diagnostic ultrasound transducer, which detected the axial tissue displacements based on acquired radiofrequency signals using a 1D cross-correlation algorithm. For pancreatic tumor detection, HMI images were generated for pancreatic tumors in transgenic mice and normal pancreases in wild-type mice. The obtained HMI images showed a high contrast between normal and malignant pancreases with an average peak-to-peak HMI displacement ratio of 3.2. Histological analysis showed that no tissue damage was associated with HMI when it was used for the sole purpose of elasticity imaging. For pancreatic tumor ablation monitoring, the focused ultrasound transducer was operated with a higher acoustic power and longer pulse length than that used in tumor detection to simultaneously induce HIFU thermal ablation and oscillatory tissue displacements, allowing HMI monitoring without interrupting tumor ablation. HMI monitoring of HIFU ablation found significant decreases in the peak-to-peak HMI displacements before and after HIFU ablation with a reduction rate ranging from 15.8% to 57.0%. The formation of thermal lesions after HIFU exposure was confirmed by histological analysis. This study demonstrated the feasibility of HMI in abdominal tumor detection and HIFU ablation monitoring. PMID:26415128

  19. Harmonic motion imaging for abdominal tumor detection and high-intensity focused ultrasound ablation monitoring: an in vivo feasibility study in a transgenic mouse model of pancreatic cancer.

    PubMed

    Chen, Hong; Hou, Gary Y; Han, Yang; Payen, Thomas; Palermo, Carmine F; Olive, Kenneth P; Konofagou, Elisa E

    2015-09-01

    Harmonic motion imaging (HMI) is a radiationforce- based elasticity imaging technique that tracks oscillatory tissue displacements induced by sinusoidal ultrasonic radiation force to assess the resulting oscillatory displacement denoting the underlying tissue stiffness. The objective of this study was to evaluate the feasibility of HMI in pancreatic tumor detection and high-intensity focused ultrasound (HIFU) treatment monitoring. The HMI system consisted of a focused ultrasound transducer, which generated sinusoidal radiation force to induce oscillatory tissue motion at 50 Hz, and a diagnostic ultrasound transducer, which detected the axial tissue displacements based on acquired radio-frequency signals using a 1-D cross-correlation algorithm. For pancreatic tumor detection, HMI images were generated for pancreatic tumors in transgenic mice and normal pancreases in wild-type mice. The obtained HMI images showed a high contrast between normal and malignant pancreases with an average peak-to-peak HMI displacement ratio of 3.2. Histological analysis showed that no tissue damage was associated with HMI when it was used for the sole purpose of elasticity imaging. For pancreatic tumor ablation monitoring, the focused ultrasound transducer was operated at a higher acoustic power and longer pulse length than that used in tumor detection to simultaneously induce HIFU thermal ablation and oscillatory tissue displacements, allowing HMI monitoring without interrupting tumor ablation. HMI monitoring of HIFU ablation found significant decreases in the peak-to-peak HMI displacements before and after HIFU ablation with a reduction rate ranging from 15.8% to 57.0%. The formation of thermal lesions after HIFU exposure was confirmed by histological analysis. This study demonstrated the feasibility of HMI in abdominal tumor detection and HIFU ablation monitoring. PMID:26415128

  20. Physical Sensing of Surface Properties by Microswimmers – Directing Bacterial Motion via Wall Slip

    PubMed Central

    Hu, Jinglei; Wysocki, Adam; Winkler, Roland G.; Gompper, Gerhard

    2015-01-01

    Bacteria such as Escherichia coli swim along circular trajectories adjacent to surfaces. Thereby, the orientation (clockwise, counterclockwise) and the curvature depend on the surface properties. We employ mesoscale hydrodynamic simulations of a mechano-elastic model of E. coli, with a spherocylindrical body propelled by a bundle of rotating helical flagella, to study quantitatively the curvature of the appearing circular trajectories. We demonstrate that the cell is sensitive to nanoscale changes in the surface slip length. The results are employed to propose a novel approach to directing bacterial motion on striped surfaces with different slip lengths, which implies a transformation of the circular motion into a snaking motion along the stripe boundaries. The feasibility of this approach is demonstrated by a simulation of active Brownian rods, which also reveals a dependence of directional motion on the stripe width. PMID:25993019

  1. Physical Sensing of Surface Properties by Microswimmers--Directing Bacterial Motion via Wall Slip.

    PubMed

    Hu, Jinglei; Wysocki, Adam; Winkler, Roland G; Gompper, Gerhard

    2015-01-01

    Bacteria such as Escherichia coli swim along circular trajectories adjacent to surfaces. Thereby, the orientation (clockwise, counterclockwise) and the curvature depend on the surface properties. We employ mesoscale hydrodynamic simulations of a mechano-elastic model of E. coli, with a spherocylindrical body propelled by a bundle of rotating helical flagella, to study quantitatively the curvature of the appearing circular trajectories. We demonstrate that the cell is sensitive to nanoscale changes in the surface slip length. The results are employed to propose a novel approach to directing bacterial motion on striped surfaces with different slip lengths, which implies a transformation of the circular motion into a snaking motion along the stripe boundaries. The feasibility of this approach is demonstrated by a simulation of active Brownian rods, which also reveals a dependence of directional motion on the stripe width. PMID:25993019

  2. Oscillatory limited compressible fluid flow induced by the radial motion of a thick-walled piezoelectric tube

    NASA Astrophysics Data System (ADS)

    Shin, Dong-Youn; Grassia, Paul; Derby, Brian

    2003-09-01

    A simple oscillatory, slightly compressible, fluid flow model in a thick-walled piezoelectric tube used in a drop-on-demand inkjet print head is developed from the point of view of fluid-structure interaction to take account of pressure wave propagation and pressure loading opposing wall motion. A frequency sweep is performed computationally using the model revealing the first acoustic fluid-structure resonance frequency and the influence of fluid viscosity. The validity of the model, with given information on the speed of sound in a fluid, is evaluated by comparing the theoretically predicted resonance frequency to the experimentally measured resonance frequency. In addition, the intrinsic speed of sound can be easily computed using the measured acoustic resonance frequency and this computed speed of sound agrees closely with speeds of sound reported in the literature.

  3. Investigation of domain wall motion in RE-TM magnetic wire towards a current driven memory and logic

    NASA Astrophysics Data System (ADS)

    Awano, Hiroyuki

    2015-06-01

    Current driven magnetic domain wall (DW) motions of ferri-magnetic TbFeCo wires have been investigated. In the case of a Si substrate, the critical current density (Jc) of DW motion was successfully reduced to 3×106 A/cm2. Moreover, by using a polycarbonate (PC) substrate with a molding groove of 600 nm width, the Jc was decreased to 6×105 A/cm2. In order to fabricate a logic in memory, a current driven spin logics (AND, OR, NOT) have been proposed and successfully demonstrated under the condition of low Jc. These results indicate that TbFeCo nanowire is an excellent candidate for next generation power saving memory and logic.

  4. Abdominal mass

    MedlinePlus

    Several conditions can cause an abdominal mass: Abdominal aortic aneurysm can cause a pulsating mass around the navel. ... This could be a sign of a ruptured aortic aneurysm, which is an emergency condition. Contact your health ...

  5. Abdominal mass

    MedlinePlus

    ... Several conditions can cause an abdominal mass: Abdominal aortic aneurysm can cause a pulsating mass around the navel. ... This could be a sign of a ruptured aortic aneurysm, which is an emergency condition. Contact your health ...

  6. Management of voluminous abdominal incisional hernia.

    PubMed

    Bouillot, J-L; Poghosyan, T; Pogoshian, T; Corigliano, N; Canard, G; Veyrie, N

    2012-10-01

    Incisional hernia is one of the classic complications after abdominal surgery. The chronic, gradual increase in size of some of these hernias is such that the hernia ring widens to a point where there is a loss of substance in the abdominal wall, herniated organs can become incarcerated or strangulated while poor abdominal motility can alter respiratory function. The surgical treatment of small (<5 cm) incisional hernias is safe and straightforward, by either laparotomy or laparoscopy. For large hernias, surgical repair is often difficult. After reintegration of herniated viscera into the abdominal cavity, the abdominal wall defect must be closed anatomically in order to restore the function to the abdominal wall. Prosthetic reinforcement of the abdominal wall is mandatory for long-term successful repair. There are multiple techniques for prosthetic hernia repair, but placement of Dacron mesh in the retromuscular plane is our preference. PMID:23137643

  7. Asymmetric Response of Ferroelastic Domain-Wall Motion under Applied Bias.

    PubMed

    Jablonski, Michael L; Liu, Shi; Winkler, Christopher R; Damodaran, Anoop R; Grinberg, Ilya; Martin, Lane W; Rappe, Andrew M; Taheri, Mitra L

    2016-02-10

    The switching of domains in ferroelectric and multiferroic materials plays a central role in their application to next-generation computer systems, sensing applications, and memory storage. A detailed understanding of the response to electric fields and the switching behavior in the presence of complex domain structures and extrinsic effects (e.g., defects and dislocations) is crucial for the design of improved ferroelectrics. In this work, in situ transmission electron microscopy is coupled with atomistic molecular dynamics simulations to explore the response of 71° ferroelastic domain walls in BiFeO3 with various orientations under applied electric-field excitation. We observe that 71° domain walls can have intrinsically asymmetric responses to opposing biases. In particular, when the electric field has a component normal to the domain wall, forward and backward domain-wall velocities can be dramatically different for equal and opposite fields. Additionally, the presence of defects and dislocations can strongly affect the local switching behaviors through pinning or nucleation of the domain walls. These results offer insight for controlled ferroelastic domain manipulation via electric-field engineering. PMID:26695346

  8. Anterior vaginal wall repair

    MedlinePlus

    Lentz GM. Anatomic defects of the abdominal wall and pelvic floor: abdominal and inguinal hernias, cystocele, urethrocele, ... uterine and vaginal prolapse: diagnosis and management. In: Lentz GM, Lobo RA, Gershenson DM, Katz VL, eds. ...

  9. JAMA Patient Page: Abdominal Hernia

    MedlinePlus

    ... an operation. Umbilical hernia Abdominal wall Intestinal loop Peritoneum Skin Peritoneum Umbilical annulus SYMPTOMS The first symptom of a ... vomiting, or constipation. Inguinal hernia Indirect inguinal hernia Peritoneum Deep inguinal ring Inguinal canal Superficial inguinal ring ...

  10. An all-metallic logic gate based on current-driven domain wall motion.

    PubMed

    Xu, Peng; Xia, Ke; Gu, Changzhi; Tang, Ling; Yang, Haifang; Li, Junjie

    2008-02-01

    The walls of magnetic domains can become trapped in a ferromagnetic metallic point contact when the thickness of the film and the width of the contact are less than their critical values. The discovery that domain walls can be moved from such constrictions by a sufficiently large current has attracted considerable attention from researchers working on both fundamental research and potential applications. Here we show that Invar nanocontacts fabricated on silica substrates exhibit a sharp drop in resistance with increasing bias voltage at room temperature in the absence of an applied magnetic field. Moreover, when two nanocontacts are combined in an all-metallic comparison circuit, it is possible to perform logical NOT operations. The use of electrical currents rather than applied magnetic fields to control the domain walls also reduces energy consumption and the risk of crosstalk in devices. PMID:18654469

  11. Contrast echocardiography in acute myocardial ischemia. III. An in vivo comparison of the extent of abnormal wall motion with the area at risk for necrosis.

    PubMed

    Kaul, S; Pandian, N G; Gillam, L D; Newell, J B; Okada, R D; Weyman, A E

    1986-02-01

    To define the in vivo relation between abnormal wall motion and the area at risk for necrosis after acute coronary occlusion, 11 open chest dogs were studied. Five dogs underwent left anterior descending coronary artery occlusion and six underwent left circumflex artery occlusion. Area at risk was defined at five short-axis levels (mitral valve, chordal, high and low papillary muscle and apex) using myocardial contrast echocardiography. Wall motion was measured in the cycles preceding injection of contrast medium. Two observers used two different methods to measure wall motion. In method A, end-diastolic to end-systolic fractional radial change for each of 32 endocardial targets was determined. The extent of abnormal wall motion was then calculated using three definitions of wall motion abnormality: akinesia/dyskinesia, fractional inward endocardial excursion of less than 10%, and fractional inward endocardial excursion of less than 20%. In method B, the information from the entire systolic contraction sequence was analyzed and correlated with a normal contraction pattern. The best linear correlation between area at risk (AR) and abnormal wall motion (AWM) was achieved using method B and expressed by the following linear regression: AWM = 0.92 AR + 3.0 (r = 0.92, p less than 0.0001, SEE = 1.7%). Of the three definitions of abnormality used in method A, the best correlation was achieved between area at risk and less than 10% inward endocardial excursion and was expressed by the following polynomial regression: AWM = -0.01 AR2 + 1.5 AR -0.14 (r = 0.92, p less than 0.001, SEE = 1.7%). These data demonstrate that there is a definite relation between area at risk and abnormal wall motion but that this relation varies depending on the method used to analyze wall motion. However, wall motion during acute ischemia is also influenced by the loading conditions of the heart. Because these may vary in a manner that is independent of the ischemic process, measurement of both

  12. Statistical methods for analysis of coordination of chest wall motion using optical reflectance imaging of multiple markers

    NASA Astrophysics Data System (ADS)

    Kenyon, C. M.; Ghezzo, R. H.; Cala, S. J.; Ferrigno, Giancarlo; Pedotti, Antonio; Macklem, P. T.; Rochester, D. F.

    1994-07-01

    To analyze coordination of chest wall motion we have used principle component analysis (PCA) and multiple regression analysis (MRA) with respect to spirometry on the displacements of 93 optical reflective markers placed upon the chest wall (CW). Each marker is tracked at 10 Hz with an accuracy of 0.2 mm in each spatial dimension using the ELITE system (IEEE Trans. Biomed. Eng. 11:943-949, 1985). PCA enables the degree of linear coordination between all of the markers to be assessed using the eigenvectors and eigenvalues of the covariance of the matrix of marker displacements in each dimension against time. Thus the number of linear degrees of freedom (DOF) which contribute more than a particular amount to the total variance can be determined and analyzed. MRA with respect to spirometrically measured lung volume changes enables identification of the CW points whose movement correlates best with lung volume. We have used this analysis to compare a quiet breathing sequence with one where tidal volume was increased fourfold involuntarily and show that the number of DOF with eigenvalues accounting for >5% of the covariance increased from 2 to 3. Also the point whose movement correlated best with lung volume changed from halfway down the lower costal margin to a more lateral point at the level of the bottom of the sternum. This quantification of CW coordination may be useful in analysis and staging of many respiratory disorders and is applicable to any nonrigid body motion where points can be tracked.

  13. Planar positron imaging of rubidium-82 for myocardial infarction: A comparison with thallium-201 and regional wall motion

    SciTech Connect

    Williams, K.A.; Ryan, J.W.; Resnekov, L.; Stark, V.; Peterson, E.L.; Gustafson, G.C.; Martin, W.B.; Freier, P.A.; Harper, P.V. )

    1989-09-01

    Rubidium-82 (Rb-82) is a generator-produced, short half-life (76 seconds) positron emitting potassium analog. Using a mobile gamma camera equipped with a rotating tungsten collimator and high-energy shielding, we examined the use of Rb-82 in the coronary care unit and clinical laboratory for detection of perfusion defects due to myocardial infarction. We studied 31 subjects, 10 patients with acute myocardial infarction, 12 with remote myocardial infarction, and nine controls. Rb-82 images were compared with Tl-201 and regional wall motion for detection of infarct-related arteries. Of the 22 patients with myocardial infarction, 16 were identified with Rb-82 and Tl-201. In nine control subjects, eight were normal with each method. Correlation between Rb-82 and Tl-201 defect scores was excellent. Sensitivity and specificity for infarct-related arteries were similar for Rb-82, Tl-201, and wall motion imaging. Thus planar Rb-82 imaging can detect MI reliably in the coronary care unit and in the clinical laboratory.

  14. Magnet Fall inside a Conductive Pipe: Motion and the Role of the Pipe Wall Thickness

    ERIC Educational Resources Information Center

    Donoso, G.; Ladera, C. L.; Martin, P.

    2009-01-01

    Theoretical models and experimental results are presented for the retarded fall of a strong magnet inside a vertical conductive non-magnetic tube. Predictions and experimental results are in good agreement modelling the magnet as a simple magnetic dipole. The effect of varying the pipe wall thickness on the retarding magnetic drag is studied for…

  15. Wall-Motion Based Analysis of Global and Regional Left Atrial Mechanics

    PubMed Central

    Moyer, Christian B.; Helm, Patrick A.; Clarke, Christopher J.; Budge, Loren P.; Kramer, Christopher M.; Ferguson, John D.; Norton, Patrick T.; Holmes, Jeffrey W.

    2015-01-01

    Atrial fibrillation is an increasingly prevalent cardiovascular disease; changes in atrial structure and function induced by atrial fibrillation and its treatments are often spatially heterogeneous. However, spatial heterogeneity of function is difficult to assess with standard imaging techniques. This paper describes a method to assess global and regional mechanical function by combining cardiac magnetic resonance imaging and finite-element surface fitting. We used this fitted surface to derive measures of left atrial volume, regional motion, and spatial heterogeneity of motion in 23 subjects, including healthy volunteers and atrial fibrillation patients. We fit the surfaces using a Newton optimization scheme in under 1 min on a standard laptop, with a root mean square error of 2.3±0.5 mm, less than 9% of the mean fitted radius, and an inter-operator variability of less than 10%. Fitted surfaces showed clear definition of the phases of left atrial motion (filling, passive emptying, active contraction) in both volume-time and regional radius-time curves. Averaged surfaces of healthy volunteers and atrial fibrillation patients provided evidence of substantial regional variation in both amount and timing of regional motion, indicating spatial heterogeneity of function, even in healthy adults. PMID:23708788

  16. On the receptivity problem for Goertler vortices: Vortex motions induced by wall roughness

    NASA Technical Reports Server (NTRS)

    Denier, James P.; Hall, Philip; Seddougui, Sharon

    1990-01-01

    The receptivity problem for Goertler vortices induced by wall roughness is investigated. The roughness is modelled by small amplitude perturbations to the curved wall over which the flow takes place. The amplitude of these perturbations is taken to be sufficiently small for the induced Goertler vortices to be described by linear theory. The roughness is assumed to vary in the spanwise direction on the boundary layer lengthscale, while in the flow direction the corresponding variation is on the lengthscale over which the wall curvature varies. In fact the latter condition can be relaxed to allow for a faster streamwise roughness variation so long as the variation does not become as fast as that in the spanwise direction. The function which describes the roughness is assumed to be such that its spanwise and streamwise dependences can be separated; this enables progress by taking Fourier or Laplace transforms where appropriate. The cases of isolated and distributed roughness elements are investigated and the coupling coefficient which relates the amplitude of the forcing and the induced vortex amplitude is found asymptotically in the small wavelength limit. It is shown that this coefficient is exponentially small in the latter limit so that it is unlikely that this mode can be stimulated directly by wall roughness. The situation at 0(1) wavelengths is quite different and this is investigated numerically for different forcing functions. It is found that an isolated roughness element induces a vortex field which grows within a wedge at a finite distance downstream of the element. However, immediately downstream of the obstacle the disturbed flow produced by the element decays in amplitude. The receptivity problem at larger Goertler numbers appropriate to relatively large wall curvature is discussed in detail.

  17. Automated classification of LV regional wall motion based on spatio-temporal profiles from cardiac cine magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Mantilla, Juan; Garreau, Mireille; Bellanger, Jean-Jacques; Paredes, José Luis

    2013-11-01

    Assessment of the cardiac Left Ventricle (LV) wall motion is generally based on visual inspection or quantitative analysis of 2D+t sequences acquired in short-axis cardiac cine-Magnetic Resonance Imaging (MRI). Most often, cardiac dynamic is globally analized from two particular phases of the cardiac cycle. In this paper, we propose an automated method to classify regional wall motion in LV function based on spatio-temporal pro les and Support Vector Machines (SVM). This approach allows to obtain a binary classi cation between normal and abnormal motion, without the need of pre-processing and by exploiting all the images of the cardiac cycle. In each short- axis MRI slice level (basal, median, and apical), the spatio-temporal pro les are extracted from the selection of a subset of diametrical lines crossing opposites LV segments. Initialized at end-diastole phase, the pro les are concatenated with their corresponding projections into the succesive temporal phases of the cardiac cycle. These pro les are associated to di erent types of information that derive from the image (gray levels), Fourier, Wavelet or Curvelet domains. The approach has been tested on a set of 14 abnormal and 6 healthy patients by using a leave-one-out cross validation and two kernel functions for SVM classi er. The best classi cation performance is yielded by using four-level db4 wavelet transform and SVM with a linear kernel. At each slice level the results provided a classi cation rate of 87.14% in apical level, 95.48% in median level and 93.65% in basal level.

  18. Speed limit in internal space of domain walls via all-order effective action of moduli motion

    NASA Astrophysics Data System (ADS)

    Eto, Minoru; Hashimoto, Koji

    2016-03-01

    We find that motion in internal moduli spaces of generic domain walls has an upper bound for its velocity. Our finding is based on our generic formula for all-order effective actions of internal moduli parameter of domain wall solitons. It is known that the Nambu-Goldstone mode Z associated with spontaneous breaking of translation symmetry obeys a Nambu-Goto effective Lagrangian √{1 -(∂0Z )2 } detecting the speed of light (|∂0Z |=1 ) in the target spacetime. Solitons can have internal moduli parameters as well, associated with a breaking of internal symmetries such as a phase rotation acting on a field. We obtain, for generic domain walls, an effective Lagrangian of the internal moduli ɛ to all orders in (∂ɛ ). The Lagrangian is given by a function of the Nambu-Goto Lagrangian: L =g (√{1 +(∂μɛ )2 }). This shows generically the existence of an upper bound on ∂0ɛ , i.e., a speed limit in the internal space. The speed limit exists even for solitons in some nonrelativistic field theories, where we find that ɛ is a type I Nambu-Goldstone mode that also obeys a nonlinear dispersion to reach the speed limit. This offers a possibility of detecting the speed limit in condensed matter experiments.

  19. Motion.

    ERIC Educational Resources Information Center

    Gerhart, James B.; Nussbaum, Rudi H.

    This monograph was written for the Conference on the New Instructional Materials in Physics held at the University of Washington in summer, 1965. It is intended for use in an introductory course in college physics. It consists of an extensive qualitative discussion of motion followed by a detailed development of the quantitative methods needed to…

  20. Motion.

    ERIC Educational Resources Information Center

    Brand, Judith, Ed.

    2002-01-01

    This issue of Exploratorium Magazine focuses on the topic of motion. Contents include: (1) "First Word" (Zach Tobias); (2) "Cosmic Collisions" (Robert Irion); (3) "The Mobile Cell" (Karen E. Kalumuck); (4) "The Paths of Paths" (Steven Vogel); (5) "Fragments" (Pearl Tesler); (6) "Moving Pictures" (Amy Snyder); (7) "Plants on the Go" (Katharine…

  1. Very Large-Scale Motions in Smooth and Rough Wall Boundary Layers

    NASA Technical Reports Server (NTRS)

    McKeon, Beverley J.; Guala, Michele; LeHew, Jeff; Jacobi, Ian

    2010-01-01

    Structural skeleton of high Reynolds number flow gives insight into smooth and rough walls. (modeling implications not yet clear) Dynamic roughness as a model of "designer" roughness: a) Impose length scale(s) and dominant frequency. b) Irregular roughness well-represented by first "few" POD modes (Christensen, 2009). Experiments and simple model demonstrate: a) Harmonics associated with forcing (and w) important. b) Change to the mean profile (skin friction).

  2. Linear modeling of turbulent skin-friction reduction due to spanwise wall motion

    NASA Astrophysics Data System (ADS)

    Duque-Daza, Carlos; Baig, Mirza; Lockerby, Duncan; Chernyshenko, Sergei; Davies, Christopher; University of Warwick Team; Imperial College Team; Cardiff University Team

    2012-11-01

    We present a study on the effect of streamwise-travelling waves of spanwise wall velocity on the growth of near-wall turbulent streaks using a linearized formulation of the Navier-Stokes equations. The changes in streak amplification due to the travelling waves induced by the wall velocity are compared to published results of direct numerical simulation (DNS) predictions of the turbulent skin-friction reduction over a range of parameters; a clear correlation between these two sets of results is observed. Additional linearized simulations but at a much higher Reynolds numbers, more relevant to aerospace applications, produce results that show no marked differences to those obtained at low Reynolds number. It is also observed that a close correlation exists between DNS data of drag reduction and a very simple characteristic of the ``generalized'' Stokes layer generated by the streamwise-travelling waves. Carlos.Duque-Daza@warwick.ac.uk - School of Engineering, University of Warwick, Coventry CV4 7AL, UK caduqued@unal.edu.co - Department of Mechanical and Mechatronics Engineering, Universidad Nacional de Colombia.

  3. Simultaneous optical mapping of transmembrane potential and wall motion in isolated, perfused whole hearts

    NASA Astrophysics Data System (ADS)

    Bourgeois, Elliot B.; Bachtel, Andrew D.; Huang, Jian; Walcott, Gregory P.; Rogers, Jack M.

    2011-09-01

    Optical mapping of cardiac propagation has traditionally been hampered by motion artifact, chiefly due to changes in photodetector-to-tissue registration as the heart moves. We have developed an optical mapping technique to simultaneously record electrical waves and mechanical contraction in isolated hearts. This allows removal of motion artifact from transmembrane potential (Vm) recordings without the use of electromechanical uncoupling agents and allows the interplay of electrical and mechanical events to be studied at the whole organ level. Hearts are stained with the voltage-sensitive dye di-4-ANEPPS and ring-shaped markers are attached to the epicardium. Fluorescence, elicited on alternate frames by 450 and 505 nm light-emitting diodes, is recorded at 700 frames/ per second by a camera fitted with a 605+/-25 nm emission filter. Marker positions are tracked in software. A signal, consisting of the temporally interlaced 450 and 505 nm fluorescence, is collected from the pixels enclosed by each moving ring. After deinterlacing, the 505 nm signal consists of Vm with motion artifact, while the 450 nm signal is minimally voltage-sensitive and contains primarily artifacts. The ratio of the two signals estimates Vm. Deformation of the tissue enclosed by each set of 3 rings is quantified using homogeneous finite strain.

  4. Details of left ventricular radial wall motion supporting the ventricular theory of the third heart sound obtained by cardiac MR

    PubMed Central

    Robson, M D; Rider, O J; Pegg, T J; Dasanu, C A; Jung, B A; Rotaru, N; Clarke, K; Holloway, C J

    2014-01-01

    Objective: Obtaining new details of radial motion of left ventricular (LV) segments using velocity-encoding cardiac MRI. Methods: Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Cine images for navigator-gated phase contrast velocity mapping were acquired using a black blood segmented κ-space spoiled gradient echo sequence with a temporal resolution of 13.8 ms. Peak systolic and diastolic radial velocities as well as radial velocity curves were obtained for 16 ventricular segments. Results: Significant differences among peak radial velocities of basal and mid-ventricular segments have been recorded. Particular patterns of segmental radial velocity curves were also noted. An additional wave of outward radial movement during the phase of rapid ventricular filling, corresponding to the expected timing of the third heart sound, appeared of particular interest. Conclusion: The technique has allowed visualization of new details of LV radial wall motion. In particular, higher peak systolic radial velocities of anterior and inferior segments are suggestive of a relatively higher dynamics of anteroposterior vs lateral radial motion in systole. Specific patterns of radial motion of other LV segments may provide additional insights into LV mechanics. Advances in knowledge: The outward radial movement of LV segments impacted by the blood flow during rapid ventricular filling provides a potential substrate for the third heart sound. A biphasic radial expansion of the basal anteroseptal segment in early diastole is likely to be related to the simultaneous longitudinal LV displacement by the stretched great vessels following repolarization and their close apposition to this segment. PMID:24641347

  5. Correlation between echocardiographic endocardial surface mapping of abnormal wall motion and pathologic infarct size in autopsied hearts.

    PubMed

    Wilkins, G T; Southern, J F; Choong, C Y; Thomas, J D; Fallon, J T; Guyer, D E; Weyman, A E

    1988-05-01

    We previously developed a cross-sectional echocardiographic technique for quantitatively mapping the endocardial surface of the left ventricle and on which regions of abnormal wall motion can be superimposed in their correct spatial distribution. This endocardial mapping technique (EMT) provides a measure of the left ventricular endocardial surface area (ESA in cm2), the area of abnormal wall motion (AWM in cm2), and the overall percent dysfunction (%AWM) as a measure of the functional "infarct size." To test this approach, we compared the EMT measurements with the actual endocardial surface area (in cm2) and pathologic infarct size (both percent infarct by volume and percent endocardial surface overlying infarct) measured at later autopsy in 20 adults (14 men, six women) ranging in age from 47 to 76 years (mean 64 +/- 9.6 years). The median interval from echocardiographic study to death was 19 days (range 1 to 269 days). Patients were divided into two groups based on the age of their infarcts at the time of death: (1) recent (infarct age less than 14 days; mean age 5.3 +/- 4.6 days) and (2) old (infarct age greater than 6 months; mean age 3.6 +/- 3 years). When the left ventricular endocardial surface area at autopsy was compared with the EMT-derived ESA, a close correlation was found (EMT area = 1.17 X autopsy area + 20.4; r = .94, p = .0001), with the systematic difference in the measurements accounted for by systolic arrest, loss of distending pressure, and specimen shrinkage. The echocardiographic measure of infarct size (%AWM) correlated well with the autopsy percent infarction by volume (%AWM = 1.1 X infarct volume + 5.5; r = .82, p = .0001). Similarly, a good correlation was found for the percent abnormal wall motion and the autopsy percent endocardial surface area overlying infarction (%AWM = 0.89 X infarct area - 0.9; r = .89, p = .0001). When the data were examined in relation to the age of the myocardial infarct, the echocardiographic %AWM appeared to

  6. Abdominal wall fat pad biopsy

    MedlinePlus

    ... J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also ... URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  7. Domain Wall Motion Across Various Grain Boundaries in Ferroelectric Thin Films

    SciTech Connect

    Marincel, Daniel M.; Zhang, Huairuo; Jesse, Stephen; Belianinov, Alex; Okatan, Mahmut B.; Kalinin, Sergei V.; Rainforth, W. Mark; Reaney, Ian M.; Randall, Clive A.; Trolier-McKinstry, Susan

    2015-03-21

    Domain wall movement at and near engineered 10°, 15°, and 24° tilt and 10° and 30° twist grain boundaries was measured by band excitation piezoresponse force microscopy for Pb(Zr,Ti)O3 films with Zr/Ti ratio of 45/55 and 52/48. A minimum in nonlinear response was observed at the grain boundary for the highest angle twist and tilt grain boundaries, while a maximum in nonlinear response was observed at the 10° tilt grain boundaries. Lastly, the observed nonlinear response was correlated to the domain structure imaged in cross section by transmission electron microscopy.

  8. Domain Wall Motion Across Various Grain Boundaries in Ferroelectric Thin Films

    DOE PAGESBeta

    Marincel, Daniel M.; Zhang, Huairuo; Jesse, Stephen; Belianinov, Alex; Okatan, Mahmut B.; Kalinin, Sergei V.; Rainforth, W. Mark; Reaney, Ian M.; Randall, Clive A.; Trolier-McKinstry, Susan

    2015-03-21

    Domain wall movement at and near engineered 10°, 15°, and 24° tilt and 10° and 30° twist grain boundaries was measured by band excitation piezoresponse force microscopy for Pb(Zr,Ti)O3 films with Zr/Ti ratio of 45/55 and 52/48. A minimum in nonlinear response was observed at the grain boundary for the highest angle twist and tilt grain boundaries, while a maximum in nonlinear response was observed at the 10° tilt grain boundaries. Lastly, the observed nonlinear response was correlated to the domain structure imaged in cross section by transmission electron microscopy.

  9. [Differential diagnosis of abdominal pain].

    PubMed

    Frei, Pascal

    2015-09-01

    Despite the frequency of functional abdominal pain, potentially dangerous causes of abdominal pain need to be excluded. Medical history and clinical examination must focus on red flags and signs for imflammatory or malignant diseases. See the patient twice in the case of severe and acute abdominal pain if lab parameters or radiological examinations are normal. Avoid repeated and useless X-ray exposure whenever possible. In the case of subacute or chronic abdominal pain, lab tests such as fecal calprotectin, helicobacter stool antigen and serological tests for celiac disease are very useful. Elderly patients may show atypical or missing clinical signs. Take care of red herrings and be skeptical whether your initial diagnosis is really correct. Abdominal pain can frequently be an abdominal wall pain. PMID:26331201

  10. A historically controlled, single-arm, multi-centre, prospective trial to evaluate the safety and efficacy of MonoMax® suture material for abdominal wall closure after primary midline laparotomy. ISSAAC-Trial [NCT005725079

    PubMed Central

    Fischer, Lars; Baumann, Petra; Hüsing, Johannes; Seidlmayer, Christoph; Albertsmeier, Markus; Franck, Annette; Luntz, Steffen; Seiler, Christoph M; Knaebel, Hanns-Peter

    2008-01-01

    Background Several randomized controlled trials have compared different suture materials and techniques for abdominal wall closure with respect to the incidence of incisional hernias after midline laparotomy and shown that it remains, irrespective of the methods used, considerably high, ranging from 9% to 20%. The development of improved suture materials which would reduce postoperative complications may help to lower its frequency. Design This is a historically controlled, single-arm, multi-centre, prospective trial to evaluate the safety of MonoMax® suture material for abdominal wall closure in 150 patients with primary elective midline incisions. INSECT patients who underwent abdominal closure using Monoplus® and PDS® will serve as historical control group. The incidences of wound infections and of burst abdomen are defined as composite primary endpoints. Secondary endpoints are the frequency of incisional hernias within one year after operation and safety. To ensure adequate comparability in surgical performance and recruitment, the 4 largest centres of the INSECT-Trial will participate. After hospital discharge, the investigators will examine the enrolled patients again at 30 days and at 12 ± 1 months after surgery. Conclusion This historically controlled, single-arm, multi-centre, prospective ISSAAC trial aims to assess whether the use of an ultra-long-lasting absorbable monofilament suture material is safe and efficient. Trial registration NCT005725079 PMID:18644124

  11. Small-scale deflagration cylinder test with velocimetry wall-motion diagnostics

    SciTech Connect

    Hooks, Daniel E; Hill, Larry G; Pierce, Timothy H

    2010-01-01

    Predicting the likelihood and effects of outcomes resultant from thermal initiation of explosives remains a significant challenge. For certain explosive formulations, the general outcome can be broadly predicted given knowledge of certain conditions. However, there remain unexplained violent events, and increased statistical understanding of outcomes as a function of many variables, or 'violence categorization,' is needed. Additionally, the development of an equation of state equivalent for deflagration would be very useful in predicting possible detailed event consequences using traditional hydrodynamic detonation moders. For violence categorization, it is desirable that testing be efficient, such that it is possible to statistically define outcomes reliant on the processes of initiation of deflagration, steady state deflagration, and deflagration to detonation transitions. If the test simultaneously acquires information to inform models of violent deflagration events, overall predictive capabilities for event likelihood and consequence might improve remarkably. In this paper we describe an economical scaled deflagration cylinder test. The cyclotetramethylene tetranitramine (HMX) based explosive formu1lation PBX 9501 was tested using different temperature profiles in a thick-walled copper cylindrical confiner. This test is a scaled version of a recently demonstrated deflagration cylinder test, and is similar to several other thermal explosion tests. The primary difference is the passive velocimetry diagnostic, which enables measurement of confinement vessel wall velocities at failure, regardless of the timing and location of ignition.

  12. A prospective comparison of echocardiographic wall motion score index and radionuclide ejection fraction in predicting outcome following acute myocardial infarction

    PubMed Central

    Galasko, G; Basu, S; Lahiri, A; Senior, R

    2001-01-01

    OBJECTIVE—To characterise echocardiographic wall motion score index (WMSI) as a surrogate measure of left ventricular ejection fraction (EF) following acute myocardial infarction (AMI) and to compare its prognostic value with that of EF measured by radionuclide ventriculography (RNV).
DESIGN—A prospective study to compare baseline echocardiographic WMSI with RNV EF in consecutive patients thrombolysed for AMI, both performed on the same day before discharge, and their relative prognostic values in predicting cardiac events.
SETTING—District general hospital coronary care unit and cardiology department.
PATIENTS—120 consecutive patients free of exclusion criteria thrombolysed for AMI and followed up for a mean (SD) of 13 (10) months.
INTERVENTIONS—None.
MAIN OUTCOME MEASURES—Correlation coefficients and receiver operating characteristic curve analyses plus cardiac event rates at follow up between RNV EF and echocardiographic WMSI.
RESULTS—WMSI correlated well with RNV EF. The best corresponding WMSIs for EFs 45%, 40%, and 35% were 0.6, 0.8, and 1.1, respectively. There were 42 cardiac events during follow up. Although both RNV EF and WMSI were strong univariate predictors of cardiac events, only WMSI independently predicted outcome in a multivariate model. All three WMSI cut offs significantly predicted events, while an RNV EF cut off of ⩽ 45% v > 45% failed to reach significance.
CONCLUSIONS—Although both RNV and echocardiographic WMSI strongly predicted cardiac outcome, WMSI, a cheaper and more readily available technique, is more discriminatory, especially in cases of mild left ventricular dysfunction following AMI.


Keywords: echocardiographic wall motion score index; radionuclide ventriculography; prognosis; acute myocardial infarction PMID:11514477

  13. Field-induced domain wall motion of amorphous [CoSiB/Pt]{sub N} multilayers with perpendicular anisotropy

    SciTech Connect

    Choi, Y. H.; Lee, K. J.; Jung, M. H.; Yoon, J. B.; Cho, J. H.; You, C.-Y.; Kim, T. W.

    2014-05-14

    Amorphous CoSiB/Pt multilayer is a perpendicular magnetic anisotropy material to achieve high squareness, low coercivity, strong anisotropy, and smooth domain wall (DW) motion, because of the smoother interface compared with crystalline multilayers. For [CoSiB(6 Å)/Pt (14 Å)]{sub N} multilayers with N = 3, 6, and 9, we studied the field-induced DW dynamics. The effective anisotropy constant K{sub 1}{sup eff} is 1.5 × 10{sup 6} erg/cm{sup 3} for all the N values, and the linear increment of coercive field H{sub c} with N gives constant exchange coupling J. By analyzing the field dependence of DW images at room temperature, a clear creep motion with the exponent μ = 1/4 could be observed. Even though the pinning field H{sub dep} slightly increases with N, the pinning potential energy U{sub c} is constant (=35 k{sub B}T) for all the N values. These results imply that the amorphous [CoSiB/Pt]{sub N} multilayers are inherently homogeneous compared to crystalline multilayers. For N ≤ 6, the pinning site density ρ{sub pin} is less than 1000/μm{sup 2}, which is about 1 pinning site per the typical device junction size of 30 × 30 nm{sup 2}. Also, the exchange stiffness constant A{sub ex} is obtained to be 0.48 × 10{sup −6} erg/cm, and the domain wall width is expected to be smaller than 5.5 nm. These results may be applicable for spin-transfer-torque magnetic random access memory and DW logic device applications.

  14. A simulation of three-dimensional systolic flow dynamics in a spherical ventricle: effects of abnormal wall motion.

    PubMed

    Gonzalez, E; Schoephoerster, R T

    1996-01-01

    Alterations in left ventricle (LV) wall motion induced by ischemia will affect flow dynamics, and these altered flow fields can be used to evaluate LV pumping efficiency. LV chamber flow fields were obtained in this study by solving the discretized three-dimensional Navier-Stokes equations for viscous, incompressible unsteady flow by using the finite analytic method. Several cases of abnormal wall motion (AWM) were simulated by a manipulation of the boundary conditions to produce regions of hypokinesis, akinesis, and dyskinesis. These solutions were used to determine the central ejection region (CER), defined as the region of flow domain in which the obtained velocity field vectors are aligned +/- 3 degrees from the LV long axis. A CER coefficient was computed from information on the location and orientation of the CER within the LV cavity. Contraction of the spherical ventricle produced a vector field that was symmetric with respect to the long axis. For the simulations of AWM, an asymmetrical flow pattern developed, became more pronounced with increasing severity of AWM, and resulted in a shorter CER that shifted toward the ischemic region. The CER coefficients decreased monotonically with increased severity in AWM from 0.948 in the normal case to a low of 0.164 for the most severe case of AWM. The CER coefficient quantitatively displayed the sensitivity of the flow patterns to even moderate degrees of hypokinesis. In addition, visualization of the three-dimensional flow field reinforced the necessity of three-dimensional simulations to capture aspects of the flow that existing methods of two-dimensional flow imaging that use ultrasound may miss. PMID:8669717

  15. Characteristic dynamic modes and domain-wall motion in magnetic nanotubes excited by resonant rotating magnetic fields

    NASA Astrophysics Data System (ADS)

    Yang, Jaehak; Kim, Junhoe; Kim, Bosung; Cho, Young-Jun; Lee, Jae-Hyeok; Kim, Sang-Koog

    2016-07-01

    We performed micromagnetic numerical calculations to explore a cylindrical nanotube's magnetization dynamics and domain-wall (DW) motions driven by eigen-circular-rotating magnetic fields of different frequencies. We discovered the presence of two different localized DW oscillations as well as asymmetric ferromagnetic resonance precession and azimuthal spin-wave modes at the corresponding resonant frequencies of the circular-rotating fields. Associated with these intrinsic modes, there exist very contrasting DW motions of different speed and propagation direction for a given DW chirality. The direction and speed of the DW propagation were found to be controllable according to the rotation sense and frequency of noncontact circular-rotating fields. Furthermore, spin-wave emissions from the moving DW were observed at a specific field frequency along with their Doppler effect. This work furthers the fundamental understanding of soft magnetic nanotubes' intrinsic dynamic modes and spin-wave emissions and offers an efficient means of manipulating the speed and direction of their DW propagations.

  16. Strain-mediated deterministic control of 360° domain wall motion in magnetoelastic nanorings

    NASA Astrophysics Data System (ADS)

    Liang, Cheng-Yen; Sepulveda, Abdon E.; Hoff, Daniel; Keller, Scott M.; Carman, Gregory. P.

    2015-11-01

    This study provides numerical simulations for deterministic 360° magnetization rotation of the transverse domain walls in a nickel nano-ring (outer diameter: 500 nm, inner diameter: 300 nm, and thickness: 10 nm) on a lead zirconate titanate (Pb[ZrxTi1-x]O3 0 < x < 1) (PZT) thin film (500 nm) deposited onto a Si substrate with surface patterned electrodes. Two alternative electrode architectures are studied, namely, a 4-electrode and a 6-electrode configuration. The 4-electrode configuration relies on magnetization dynamics to produce an overshoot coupled with proper timing control of the voltage applied to achieve 360° magnetization rotation. In contrast, the 6-electrode configuration only requires sequential voltage application to successive pairs of electrodes and thus can be operated at quasi-static speeds and does not rely on magnetization dynamics to achieve 360° magnetization rotation. These analytical models provide support for developing new devices such as nanoscale multiferroic driven electromagnetic motors.

  17. Influence of nonlocal damping on the field-driven domain wall motion

    NASA Astrophysics Data System (ADS)

    Yuan, H. Y.; Yuan, Zhe; Xia, Ke; Wang, X. R.

    2016-08-01

    We derive a general expression of nonlocal damping in noncollinear magnetization due to the nonuniform spin current pumped by precessional magnetization and incorporate it into a generalized Thiele equation to study its effects on the dynamics of the transverse and vortex domain walls (DWs) in ferromagnetic nanowires. We demonstrate that the transverse component of nonlocal damping slows down the field-driven DW propagation and increases the Walker breakdown field, whereas it is neglected in many previous works in literature. The experimentally measured DW mobility variation with the damping tuned by doping with heavy rare-earth elements that had discrepancy from micromagnetic simulation is now well understood with the nonlocal damping. Our results suggest that the nonlocal damping should be properly included as a prerequisite for quantitative studies of current-induced torques in noncollinear magnetization.

  18. Reconstruction option of abdominal wounds with large tissue defects

    PubMed Central

    2014-01-01

    Background Abdominal wall defects result from trauma, abdominal wall tumors, necrotizing infections or complications of previous abdominal surgeries. Apart from cosmetics, abdominal wall defects have strong negative functional impact on the patients. Many different techniques exist for abdominal wall repair. Most problematic and troublesome are defects, where major part of abdominal wall had to be resected and tissue for transfer or reconstruction is absent. Case presentation Authors of the article present operative technique, in which reconstruction of abdominal wall was managed by composite polypropylene mesh with absorbable collagen film, creation of granulation tissue with use of NPWT (negative pressure wound therapy), and subsequent split skin grafting. Three patients with massive abdominal wall defect were successfully managed and abdominal wall reconstruction was performed by mentioned technique. Functional and cosmetic effect is acceptable and patients have good postoperative quality of life. Conclusions Patients with giant abdominal defects can benefit from described technique. It serves as the only option, with which abdominal wall is fully reconstructed without need for the secondary intervention. PMID:25103782

  19. An in situ diffraction study of domain wall motion contributions to the frequency dispersion of the piezoelectric coefficient in lead zirconate titanate

    SciTech Connect

    Seshadri, Shruti B.; Prewitt, Anderson D.; Jones, Jacob L.; Studer, Andrew J.; Damjanovic, Dragan

    2013-01-28

    The contribution of non-180 Degree-Sign domain wall displacement to the frequency dependence of the longitudinal piezoelectric coefficient has been determined experimentally in lead zirconate titanate using time-resolved, in situ neutron diffraction. Under subcoercive electric fields of low frequencies, approximately 3% to 4% of the volume fraction of non-180 Degree-Sign domains parallel to the field experienced polarization reorientation. This subtle non-180 Degree-Sign domain wall motion directly contributes to 64% to 75% of the magnitude of the piezoelectric coefficient. Moreover, part of the 33 pm/V decrease in piezoelectric coefficient across 2 orders of magnitude in frequency is quantitatively attributed to non-180 Degree-Sign domain wall motion effects.

  20. Usefulness of heavy isometric exercise echocardiography for assessing left ventricular wall motion patterns late (> or = 6 months) after acute myocardial infarction.

    PubMed

    Fisman, E Z; Ben-Ari, E; Pines, A; Drory, Y; Motro, M; Kellermann, J J

    1992-11-01

    The aim of this prospective study was to determine the effects of heavy isometric exercise on left ventricular (LV) wall motion patterns in patients who have had myocardial infarction, and to compare heavy isometric exercise with dynamic exercise for competence in eliciting LV wall motion abnormalities at equivalent rate-pressure products. Echocardiography was performed in 42 patients during supine bicycle ergometry and during heavy dynamometer stretching at 50% of maximal voluntary contraction. Systemic vascular resistance increased from 1,484 to 1,649 dynes s cm-5 (p < 0.05) during isometric exercise, and decreased significantly during dynamic exercise. Wall motion abnormalities or new asynergy were induced by isometric exercise in 120 segments, 107 of which (89%) showed significant stenosis of the perfusing coronary artery. Hypokinesia was the dominant pattern in the range of 76 to 90% narrowing; akinesia was dominant at 91 to 100% narrowing. Wall motion abnormalities were also documented in 13 segments (11%) assumed to be supplied by vessels with nonsignificant stenosis. Dyskinesia, seen in 7% of the segments, was equally distributed between both groups with significant stenosis. Sensitivity and positive predictive value in identifying specific coronary vessel disease was similar for both isometric and dynamic exercise. In conclusion, heavy isometric exercise in patients who have had myocardial infarction induces wall motion abnormalities of a severity proportional to the degree of coronary narrowing. This exercise method is similar to dynamic exercise for ability in identifying obstructions in a specific vessel. Furthermore, when compared at near-equal rate-pressure products, heavy isometric exercise is far superior in sensitivity to dynamic exercise. PMID:1414932

  1. Abdominal sounds

    MedlinePlus

    ... during sleep. They also occur normally for a short time after the use of certain medicines and after abdominal surgery. Decreased or absent bowel sounds often indicate constipation. Increased ( hyperactive ) bowel sounds ...

  2. Abdominal MRI

    MedlinePlus

    ... provider if you have: Artificial heart valves Brain aneurysm clips Heart defibrillator or pacemaker Inner ear (cochlear) ... which the test may be performed: Abdominal aortic aneurysm Atheroembolic renal disease Carcinoma of the renal pelvis ...

  3. Abdominal pain

    MedlinePlus

    ... threatening conditions, such as colon cancer or early appendicitis , may only cause mild pain or no pain. ... Food poisoning Stomach flu Other possible causes include: Appendicitis Abdominal aortic aneurysm (bulging and weakening of the ...

  4. Abdominal Pain

    MedlinePlus

    ... can help the overall situation for the child. Teaching kids self-hypnosis [8] or guided imagery [8a] ... related topics? Functional Abdominal Pain (English, French or Spanish)—from The North American Society for Pediatric Gastroenterology, ...

  5. A new attenuation model of near-fault ground motions with consideration of the hanging wall effect in the Wenchuan earthquake

    NASA Astrophysics Data System (ADS)

    Peng, Lei; Xie, Lili; Hu, Jinjun; Wang, Dong

    2011-09-01

    The hanging wall effect is an important factor that impacts the characteristics of strong ground motions in near-fault areas. Based on a residual analysis of ground motion parameters characterizing the hanging wall effect and in recognition of the nature of the effect, many models have been developed. In this study, after a comprehensive analysis of two existing models, a new model is proposed and used to model the hanging wall effect in horizontal peak ground acceleration (PGAH) and spectral acceleration (SAH) at a period of 0.1 s in the Wenchuan earthquake. Finally, comparisons between the modeling results of the hanging wall effect in the Wenchuan earthquake and the results predicted by using Abrahamson and Silva's NGA model (AS NGA) indicate that the AS NGA model predicts a much higher hanging wall effect than the model developed in this paper. Furthermore, the AS NGA model predicts a large hanging wall effect even at great distances, while the proposed model more accurately captures the trend of the effect.

  6. A formula for the wall-amplified added mass coefficient for a solid sphere in normal approach to a wall and its application for such motion at low Reynolds number

    NASA Astrophysics Data System (ADS)

    Yang, F.-L.

    2010-12-01

    This work re-examines the potential flow theory for a sphere in normal approach to a wall, based on the classical results derived by Lamb [Hydrodynamics (Dover, New York, 1932)] and Milne-Thomson [Theoretical Hydrodynamics, 5th ed. (Dover, New York, 1968)]. These authors generated an expression in which the kinetic energy for a sphere in an unbounded fluid is augmented by a wall correction function in terms of an infinite series that depends on the scaled center-to-wall distance, h∗=h/a, with a denoting the sphere radius. By truncating the series at the order of h∗-3, the resulting one-term correction function, 3/8h∗-3, is widely employed to approximate the wall-amplified added mass coefficient, CAM(h ∗), in multiphase flow research. Nonetheless, this work shows that this one-term correction deviates greatly from corrections including higher order terms when the interstitial gap drops below the half sphere radius. Thus, an explicit formula is developed, for all h∗, using a near-wall Padé approximation, an intermediate bridging function, and a far-field approximation. This proposed formula provides an efficient and reasonable approximation to the infinite series and thus may serve as an improved wall correction function as compared to the one-term formula. The developed formula is applied to compute the unsteady approach of a nonrotating sphere toward a wall in a viscous fluid at low Reynolds number condition. In addition to Brenner's wall correction on the quasisteady viscous force [H. Brenner, "The slow motion of a sphere through a viscous fluid towards a plane surface," Chem. Eng. Sci. 16, 242 (1961)], the current formula is employed to modify both the added mass coefficient, from 1/2, and the history force. This latter force is modified by integrating the wall-modified potential flow theory with the boundary layer theory. If the one-term correction is used in the equation of motion, underestimation of the sphere motion and the force magnitudes are

  7. Acute incarcerated external abdominal hernia

    PubMed Central

    Yang, Xue-Fei

    2014-01-01

    External abdominal hernia occurs when abdominal organs or tissues leave their normal anatomic site and protrude outside the skin through the congenital or acquired weakness, defects or holes on the abdominal wall, including inguinal hernia, umbilical hernia, femoral hernia and so on. Acute incarcerated hernia is a common surgical emergency. With advances in minimally invasive devices and techniques, the diagnosis and treatment have witnessed major changes, such as the use of laparoscopic surgery in some cases to achieve minimally invasive treatment. However, strict adherence to the indications and contraindications is still required. PMID:25489584

  8. Early Indium-111 antimyosin scintigraphy for assessment of regional wall motion asynergy on discharge after myocardial infarction

    SciTech Connect

    van Vlies, B.; Baas, J.; Visser, C.A.; van Royen, E.; Delemarre, B.J.; Bot, H.; Dunning, A.J. )

    1990-01-01

    To assess the relation between early Indium-111 monoclonal antimyosin antibody scintigraphy and degree of regional asynergy on discharge, 38 patients with a first acute myocardial infarct were studied (18 anterior, 20 inferoposterior infarctions). In 21 patients thrombolytic therapy was administered. On the first day of myocardial infarction, 80 MBq Indium-111 Antimyosin was injected. Planar images, anterior, lateral and left anterior oblique, were made 24 hours later. Localized myocardial uptake was present in 37/38 patients, and was evaluated for Count Density Index (count density of infarct zone/left lung count density) in the left anterior oblique images, which displayed the infarct zone well. Regional asynergy on discharge was evaluated by cross-sectional echocardiography and defined mild (hypokinesia) or severe (akinesia or dyskinesia). Count density index was significantly lower in 15 patients with mild asynergy, compared with 22 patients with severe asynergy (1.61 +/- 0.25 vs. 2.42 +/- 0.40, p less than 0.001). This difference was present in both patient groups treated with or without thrombolysis. We conclude that early count density index, reflecting the amount of local necrosis, is highly correlated to the ultimate degree of wall motion impairment.

  9. Short and long term predictive value of admission wall motion score in acute myocardial infarction. A cross sectional echocardiographic study of 345 patients.

    PubMed Central

    Kan, G; Visser, C A; Koolen, J J; Dunning, A J

    1986-01-01

    A score of left ventricular segmental wall motion was used as a convenient rapid way to assess overall left ventricular function in acute myocardial infarction. Its success in risk stratification at admission was assessed by a blind review of cross sectional echocardiographic tape recordings from multiple acoustic windows. Sixty nine (20%) of the 345 patients died during hospital stay or within a one year follow up. The mean (SD) wall motion score in those who died was significantly higher than in those who survived (16.2 (5.9) vs 5.7 (3.9)). There were no differences between the group that died in hospital within three months of discharge and the group that died between three months and one year after discharge. Among the 31 patients who died in hospital, however, wall motion score was highest in 15 patients dying of cardiogenic shock (19.2 (4.2)). In 16 patients with lethal ruptures it was 13.5 (6.1). The nine patients with free wall ruptures had higher wall motion scores than those with ventricular septal rupture or papillary muscle rupture (15.7 (6.9) vs 8.5 (5.3)). Eight (3.3%) of 245 patients with a score less than 10 died, compared with 61 (61%) of 100 scoring greater than or equal to 10. The sensitivity of a score of greater than or equal to 10 in predicting death within one year was 88%, the specificity was 86%, the positive predictive value was 61%, and the negative predictive value was 97%. PMID:3790378

  10. Postherpetic pseudohernia: delayed onset of paresis of abdominal muscles due to herpes zoster causing an ipsilateral abdominal bulge.

    PubMed

    Ohno, Shunsuke; Togawa, Yasuhiro; Chiku, Tsuyoshi; Sano, Wataru

    2016-01-01

    Postherpetic pseudohernia causes an abdominal bulge as well as an abdominal wall herniation. This disease is one of the neurological complications of herpes zoster and essentially consists of paresis of ipsilateral abdominal muscles. Postherpetic pseudohernia may be mistaken for abdominal wall herniation because it is not well known. We describe two cases presenting an abdominal bulge. The ipsilateral abdominal bulge appeared after recovery from abdominal zoster. Abdominal CT showed no evidence of a herniation or mass. We diagnosed a postherpetic pseudohernia. One of the patients recovered spontaneously 4 months after the onset, and the other partially recovered after 2 months. This disease can be expected to disappear spontaneously, unlike abdominal herniation requiring surgery. It has been reported that 79.3% of patients eventually recovered spontaneously. For surgeons and general practitioners, it is beneficial to keep this disease in mind when examining a patient presenting an abdominal bulge. PMID:27229900

  11. Controlling magnetic domain wall motion in the creep regime in He{sup +}-irradiated CoFeB/MgO films with perpendicular anisotropy

    SciTech Connect

    Herrera Diez, L. García-Sánchez, F.; Adam, J.-P.; Devolder, T.; Eimer, S.; El Hadri, M. S.; Ravelosona, D.; Lamperti, A.; Mantovan, R.; Ocker, B.

    2015-07-20

    This study presents the effective tuning of perpendicular magnetic anisotropy in CoFeB/MgO thin films by He{sup +} ion irradiation and its effect on domain wall motion in a low field regime. Magnetic anisotropy and saturation magnetisation are found to decrease as a function of the irradiation dose which can be related to the observed irradiation-induced changes in stoichiometry at the CoFeB/MgO interface. These changes in the magnetic intrinsic properties of the film are reflected in the domain wall dynamics at low magnetic fields (H) where irradiation is found to induce a significant decrease in domain wall velocity (v). For all irradiation doses, domain wall velocities at low fields are well described by a creep law, where Ln(v) vs. H{sup −1∕4} behaves linearly, up to a maximum field H*, which has been considered as an approximation to the value of the depinning field H{sub dep}. In turn, H* ≈ H{sub dep} is seen to increase as a function of the irradiation dose, indicating an irradiation-induced extension of the creep regime of domain wall motion.

  12. Controlling magnetic domain wall motion in the creep regime in He+-irradiated CoFeB/MgO films with perpendicular anisotropy

    NASA Astrophysics Data System (ADS)

    Herrera Diez, L.; García-Sánchez, F.; Adam, J.-P.; Devolder, T.; Eimer, S.; El Hadri, M. S.; Lamperti, A.; Mantovan, R.; Ocker, B.; Ravelosona, D.

    2015-07-01

    This study presents the effective tuning of perpendicular magnetic anisotropy in CoFeB/MgO thin films by He+ ion irradiation and its effect on domain wall motion in a low field regime. Magnetic anisotropy and saturation magnetisation are found to decrease as a function of the irradiation dose which can be related to the observed irradiation-induced changes in stoichiometry at the CoFeB/MgO interface. These changes in the magnetic intrinsic properties of the film are reflected in the domain wall dynamics at low magnetic fields (H) where irradiation is found to induce a significant decrease in domain wall velocity (v). For all irradiation doses, domain wall velocities at low fields are well described by a creep law, where Ln(v) vs. H-1/4 behaves linearly, up to a maximum field H*, which has been considered as an approximation to the value of the depinning field Hdep. In turn, H* ≈ Hdep is seen to increase as a function of the irradiation dose, indicating an irradiation-induced extension of the creep regime of domain wall motion.

  13. Abdominal Sepsis.

    PubMed

    De Waele, Jan J

    2016-08-01

    Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy. PMID:27363829

  14. Diagnostic accuracy of myocardial deformation indices for detecting high risk coronary artery disease in patients without regional wall motion abnormality

    PubMed Central

    Rostamzadeh, Alireza; Shojaeifard, Maryam; Rezaei, Yousef; Dehghan, Kasra

    2015-01-01

    Background: The prediction of coronary artery disease (CAD) by conventional echocardiographic measurements is principally based on the estimation of ejection fraction and regional wall motion abnormality (RWMA). This study aimed to determine whether strain echocardiography of left ventricle measured by velocity vector imaging (VVI) method could detect patients with a high-risk CAD. Methods: In a prospective study, a total of 119 consecutive patients who were assessed for eligibility were categorized into three groups: (1) without CAD as normal (n=59), (2) 1- or 2-vessel disease as low-risk (n=29), and (3) left main and/or 3-vessel disease as high-risk (n=31). The peaks of systolic strain and strain rate from 18 curves of apical views were averaged as global longitudinal strain and strain rate (GLS and GLSR), respectively; the 6 systolic peaks of strain and strain rate at base- and mid-ventricular of short axis views were averaged as mean radial strain rate (MRSR). Results: GLS, GLSR, and basal MRSR of left ventricle were significantly lower in the high-risk group (P=0.047, P=0.004 and P=0.030, respectively). Receiver operating characteristics curve showed that the optimal values of GLS, GLSR, and basal MRSR for detecting the severe CAD were -17%, -1 s-1, and 1.45 s-1 with the sensitivities of 77%, 71%, and 71% and the specificities of 63%, 67%, and 62%, respectively. Conclusion: Decrements in the GLS, GLSR, and basal MRSR of the left ventricle can detect the high-risk CAD cases among patients without RWMA at rest. PMID:26309603

  15. Wall motion in the stenotic carotid artery: association with greyscale plaque characteristics, the degree of stenosis and cerebrovascular symptoms

    PubMed Central

    2013-01-01

    Background Systolic dilation of the atherosclerotic carotid artery depends on several factors including arterial compliance and the haemodynamic environment. The purpose of this study was to quantify wall motion in stenotic carotid arteries and investigate any associations with the ultrasound greyscale plaque characteristics, the degree of stenosis, and the presence of cerebrovascular symptoms. Methods Variations in the lumen diameters of 61 stenotic carotid arteries (stenosis range 10%-95%) from 47 patients were measured before the proximal shoulder of the atherosclerotic plaque using ultrasound image sequences over several cardiac cycles. Absolute and percentage diameter changes from diastole to systole were calculated and their relationship to the degree of stenosis, greyscale plaque characteristics, and the presence of ipsilateral hemispheric symptoms were studied. Results The mean absolute diameter change from diastole to systole was 0.45 mm (s.d. 0.17), and the mean percentage diameter change was 6.9% (s.d. 3.1%). Absolute and percentage diameter changes did not have a statistically significant relationship to the degree of stenosis, greyscale plaque characteristics, or the presence of ipsilateral hemispheric symptoms (p > 0.05). Parameters significantly correlated with the presence of symptoms were the degree of stenosis (p = 0.01), plaque greyscale median (p = 0.02) and the plaque surface irregularity index (p = 0.02). Conclusions Our study confirmed the degree of stenosis, plaque greyscale median and our surface irregularity index were significant predictors of symptoms, but found no significant correlation between diameter changes of stenosed carotid arteries and the presence of ipsilateral hemispheric symptoms. PMID:24139162

  16. High-risk subgroup of inferior myocardial infarction: importance of anterior wall motion and right ventricular function.

    PubMed

    Nishimura, T; Yasuda, T; Gold, H K; Leinbach, R C; Boucher, C A; McKusick, K A; Strauss, H W

    1986-01-01

    To identify high-risk subgroups of inferior myocardial infarction, 75 patients presenting with their first inferior infarction were investigated by sequential gated blood pool scans. The patients were divided into four groups based on the right ventricular function (RVF) and anterior wall motion (AWM) of the left ventricle by scan at the time of admission. A second blood pool scan was performed at ten days to evaluate RV and LV function. Thirty-eight patients had cardiac catheterization before discharge and all patients were followed up for one year to determine their clinical outcome. Depressed RVF and reduced AWM were observed in 26 (35%) (Group A); depressed RVF and normal AWM were found in 20 (27%) (Group B); reduced AWM and normal RVF in 10 (13%) (Group C); and normal RVF and AWM in 19 (25%) (Group D). The mean values of biventricular function (LVEF, RVEF) in groups A, B, C, and D were (44.9 +/- 8.4%, 32.5 +/- 9.9%), (59.9 +/- 8.6%, 34.5 +/- 8.0%), (44.9 +/- 15.7%, 48.2 +/- 3.3%), and (60.4 +/- 9.1%, 51.6 +/- 10.6%), respectively, at admission. In serial measurements, LVEF did not change significantly in any group, however, RVEF improved nearly 10 points in groups A and B at 10 days. Group A also had the highest incidence (82%) of left anterior descending coronary artery involvement, and the highest mean creatine phosphokinase levels (762 +/- 318 U/l): Furthermore, group A had a high incidence of major complications during their hospital course and high mortality during the one-year follow-up. These data clearly identified group A as a high-risk subgroup of patients with inferior infarction. PMID:3602422

  17. The dynamics of the asymmetric motion of domain walls of sandwich domain structure in a Fe-based amorphous ribbon

    NASA Astrophysics Data System (ADS)

    Zhmetko, D. N.; Zhmetko, S. D.; Troschenkov, Y. N.; Matsura, A. V.

    2013-08-01

    The frequency dependence of asymmetry of the domain walls velocity relative to the middle plane of amorphous ribbon is investigated. An additional pressure of the same direction acting on each domain wall caused by dependence of eddy current damping on the coordinate of the domain wall is revealed. The microscopic mechanisms of this additional pressure are considered.

  18. New method for detecting domain wall trapping and motion at a constriction in narrow ferromagnetic wires using perpendicular-current giant magnetoresistance

    NASA Astrophysics Data System (ADS)

    Zambano, Antonio Javier

    We present a versatile, new method for detecting the presence and small motions of a trapped domain wall in a narrow ferromagnetic wire using current-perpendicular-to-plane, CPP, giant magnetoresistance, GMR. We have adapted the Ono et al.1-2 method for trapping domain walls to CPP GMR measurements. We shaped a spin valve multilayer Cu(10nm)/Py(20nm)/Cu(10nm)/Py(5nm)/Cu(5nm)/Au(15nm), where Py = Ni84 Fe16, into a long ˜500-nm-wide wire with a U-shaped or V-shaped constriction (notch) near its middle that acts as a trapping site for a head-to-head (or tail-to-tail) domain wall. A sweeping external magnetic field, H, is applied along the wire axis. The magnetization is restricted to be parallel to the wire axis due to the shape anisotropy. Magnetization reversal in the wire takes place by propagation of a magnetic domain wall, which initially nucleates in a diamond-shaped reservoir and is injected from there into the nanowire at a particular value of H. As a wall in either Py layer moves past the measuring contact, the CPP GMR detects the change of the relative magnetizations of the two Py layers, from parallel to antiparallel. The CPP GMR response to small motions of the trapped domain wall is enhanced because the CPP current is restricted to the region of wall trapping; but in addition, the CPP current can be also localized to a measuring region outside the constriction. Superconducting 150-nm-thick (top) and 100-nm-thick (bottom) Nb contacts are used to obtain a uniform CPP current density in the wall trapping region at 4.2 K; but measurements at 295K, including 200-nm-Au top contacts, have also been successful with non-uniform CPP currents. Data for the two different types of constrictions show that for U-shape notches, several pinning sites were seen as the wall in the thinner Py layer remained trapped in the constriction, while in V-shaped notches one trapping site occurred. Successful pinning of a wall at the constriction in the thicker Py layer was more

  19. Audiovisual biofeedback improves motion prediction accuracy

    PubMed Central

    Pollock, Sean; Lee, Danny; Keall, Paul; Kim, Taeho

    2013-01-01

    Purpose: The accuracy of motion prediction, utilized to overcome the system latency of motion management radiotherapy systems, is hampered by irregularities present in the patients’ respiratory pattern. Audiovisual (AV) biofeedback has been shown to reduce respiratory irregularities. The aim of this study was to test the hypothesis that AV biofeedback improves the accuracy of motion prediction. Methods: An AV biofeedback system combined with real-time respiratory data acquisition and MR images were implemented in this project. One-dimensional respiratory data from (1) the abdominal wall (30 Hz) and (2) the thoracic diaphragm (5 Hz) were obtained from 15 healthy human subjects across 30 studies. The subjects were required to breathe with and without the guidance of AV biofeedback during each study. The obtained respiratory signals were then implemented in a kernel density estimation prediction algorithm. For each of the 30 studies, five different prediction times ranging from 50 to 1400 ms were tested (150 predictions performed). Prediction error was quantified as the root mean square error (RMSE); the RMSE was calculated from the difference between the real and predicted respiratory data. The statistical significance of the prediction results was determined by the Student's t-test. Results: Prediction accuracy was considerably improved by the implementation of AV biofeedback. Of the 150 respiratory predictions performed, prediction accuracy was improved 69% (103/150) of the time for abdominal wall data, and 78% (117/150) of the time for diaphragm data. The average reduction in RMSE due to AV biofeedback over unguided respiration was 26% (p < 0.001) and 29% (p < 0.001) for abdominal wall and diaphragm respiratory motion, respectively. Conclusions: This study was the first to demonstrate that the reduction of respiratory irregularities due to the implementation of AV biofeedback improves prediction accuracy. This would result in increased efficiency of motion

  20. Abdominal thrusts

    MedlinePlus

    ... call 911 . If the person loses consciousness, start CPR . If you are not comfortable performing abdominal thrusts, ... American Red Cross. First Aid/CPR/AED Participant's Manual. 2nd ... Red Cross; 2014. Berg RA, Hemphill R, Abella BS, et al. Part 5: ...

  1. Abdominal Adhesions

    MedlinePlus

    ... Adhesions 1 Ward BC, Panitch A. Abdominal adhesions: current and novel therapies. Journal of Surgical Research. 2011;165(1):91–111. Seek Help for ... and how to participate, visit the NIH Clinical Research Trials and You website ... Foundation for Functional Gastrointestinal Disorders 700 West Virginia ...

  2. Effects of aortic root motion on wall stress in the Marfan aorta before and after personalised aortic root support (PEARS) surgery.

    PubMed

    Singh, S D; Xu, X Y; Pepper, J R; Izgi, C; Treasure, T; Mohiaddin, R H

    2016-07-01

    Aortic root motion was previously identified as a risk factor for aortic dissection due to increased longitudinal stresses in the ascending aorta. The aim of this study was to investigate the effects of aortic root motion on wall stress and strain in the ascending aorta and evaluate changes before and after implantation of personalised external aortic root support (PEARS). Finite element (FE) models of the aortic root and thoracic aorta were developed using patient-specific geometries reconstructed from pre- and post-PEARS cardiovascular magnetic resonance (CMR) images in three Marfan patients. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Cardiovascular MR cine images were used to quantify aortic root motion, which was imposed at the aortic root boundary of the FE model, with zero-displacement constraints at the distal ends of the aortic branches and descending aorta. Measurements of the systolic downward motion of the aortic root revealed a significant reduction in the axial displacement in all three patients post-PEARS compared with its pre-PEARS counterparts. Higher longitudinal stresses were observed in the ascending aorta when compared with models without the root motion. Implantation of PEARS reduced the longitudinal stresses in the ascending aorta by up to 52%. In contrast, the circumferential stresses at the interface between the supported and unsupported aorta were increase by up to 82%. However, all peak stresses were less than half the known yield stress for the dilated thoracic aorta. PMID:27255604

  3. Relationship of lower extremity alignment during the wall squat and single-leg jump: assessment of single-leg landing using three-dimensional motion analysis

    PubMed Central

    Watanabe, Manabu; Matsumoto, Takaaki; Ono, Susumu; Koseki, Hirohisa; Watarai, Koji

    2016-01-01

    [Purpose] The purpose of this study was to evaluate the relationship between malalignment and lower-extremity injury and to determine the optimal dynamic alignment of the lower extremity with wall squats. [Subjects and Methods] Healthy individuals from one therapy school were enrolled and assigned to a wall squat normal or abnormal group based on their forms during wall squats. The abnormal group was found to be more prone to lower-extremity injury on three-dimensional motion analysis. Eight students from each group were randomly chosen for the study. The effects of single-leg landing movements were assessed using three-dimensional motion analysis. [Results] In the sagittal plane, significant flexion of the hip and knee joints occurred 0.02 and 0.04 seconds after initial foot contact with the ground in the normal and abnormal groups, respectively. In the frontal plane, significant adduction of the hip joint occurred at 0.07 seconds in the abnormal group. [Conclusion] The abnormal group tended to display later flexion of the hip and knee joints and narrower hip, knee, and ankle range of motion than the normal group, suggesting that dynamic alignment of the lower extremity in the abnormal group likely made them susceptible to injury. PMID:27390393

  4. Relationship of lower extremity alignment during the wall squat and single-leg jump: assessment of single-leg landing using three-dimensional motion analysis.

    PubMed

    Watanabe, Manabu; Matsumoto, Takaaki; Ono, Susumu; Koseki, Hirohisa; Watarai, Koji

    2016-06-01

    [Purpose] The purpose of this study was to evaluate the relationship between malalignment and lower-extremity injury and to determine the optimal dynamic alignment of the lower extremity with wall squats. [Subjects and Methods] Healthy individuals from one therapy school were enrolled and assigned to a wall squat normal or abnormal group based on their forms during wall squats. The abnormal group was found to be more prone to lower-extremity injury on three-dimensional motion analysis. Eight students from each group were randomly chosen for the study. The effects of single-leg landing movements were assessed using three-dimensional motion analysis. [Results] In the sagittal plane, significant flexion of the hip and knee joints occurred 0.02 and 0.04 seconds after initial foot contact with the ground in the normal and abnormal groups, respectively. In the frontal plane, significant adduction of the hip joint occurred at 0.07 seconds in the abnormal group. [Conclusion] The abnormal group tended to display later flexion of the hip and knee joints and narrower hip, knee, and ankle range of motion than the normal group, suggesting that dynamic alignment of the lower extremity in the abnormal group likely made them susceptible to injury. PMID:27390393

  5. Current-driven domain wall motion due to volume spin transfer torque in Co/Ni multilayer systems on Au underlayer

    NASA Astrophysics Data System (ADS)

    Ryu, Kwang-Su; Yang, See-Hun; Thomas, Luc; Parkin, Stuart

    2016-09-01

    We have studied the current-induced domain wall (CIDW) dynamics in perpendicularly magnetized Co/Ni multilayers deposited on Au underlayer, where the conventional spin transfer torque governs the domain wall dynamics, by the Kerr microscope. It is found that the DW angle tilting following Oersted field profile plays an important role in domain wall (DW) motion at high current density J by decreasing DW velocity with the increasing J, while distorting its DW morphology. Also we find that the DW pinning becomes pronounced as the anisotropy decreases by increasing number of Co/Ni repeats. Most remarkably, the DW tilting angle changes its sign by inserting ultrathin Pt layer between Au and Co layer, which suggests that the Dzyaloshinskii–Moriya interaction and spin Hall effect induces opposite effect in DW tilting. Our findings can be of use for application of CIDW to spintronics with perpendicularly magnetized systems.

  6. Abdominal Aortic Aneurysms: Treatments

    MedlinePlus

    ... information Membership Directory (SIR login) Interventional Radiology Abdominal Aortic Aneurysms Interventional Radiologists Treat Abdominal Aneurysms Nonsurgically Interventional radiologists ...

  7. Abdominal trauma by ostrich

    PubMed Central

    Usurelu, Sergiu; Bettencourt, Vanessa; Melo, Gina

    2015-01-01

    Introduction Ostriches typically avoid humans in the wild, since they correctly assess humans as potential predators, and, if approached, often run away. However, ostriches may turn aggressive rather than run when threatened, especially when cornered, and may also attack when they feel the need to defend their offspring or territories. Presentation of case A 71-year-old male patient presented with intra abdominal injury sustained from being kicked in the abdominal wall by an ostrich. During laparotomy, were found free peritoneal effusion and perforation of the small intestine. Discussion The clinical history and physical examination are extremely important for diagnostic and therapeutic decision making. CT-scan is the most accurate exam for making diagnosis. Surgery is the treatment of choice, and is always indicated when there is injury to the hollow viscera. In general it is possible to suture the defect. Conclusion In cases of blunt abdominal trauma by animals is necessary to have a low threshold of suspicion for acute abdomen. PMID:25685344

  8. Abdominal rigidity

    MedlinePlus

    Causes can include: Abscess inside the abdomen Appendicitis Cholecystitis caused by gallstones Hole that develops through the entire wall of the stomach, small intestine, large bowel, or gallbladder ( gastrointestinal perforation ) Injury ...

  9. Evaluation of Hip Internal and External Rotation Range of Motion as an Injury Risk Factor for Hip, Abdominal and Groin Injuries in Professional Baseball Players

    PubMed Central

    Ma, Richard; Zhou, Hanbing; Thompson, Matthew; Dawson, Courtney; Nguyen, Joseph; Coleman, Struan

    2015-01-01

    Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86). Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries. PMID:26793294

  10. Evaluation of Hip Internal and External Rotation Range of Motion as an Injury Risk Factor for Hip, Abdominal and Groin Injuries in Professional Baseball Players.

    PubMed

    Li, Xinning; Ma, Richard; Zhou, Hanbing; Thompson, Matthew; Dawson, Courtney; Nguyen, Joseph; Coleman, Struan

    2015-12-28

    Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86). Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries. PMID:26793294

  11. Ultrasonographic diagnosis in abdominal tuberculosis.

    PubMed

    Sheikh, M; Moosa, I; Hussein, F M; Qurttom, M A; Behbehani, A I

    1999-05-01

    Sonographic findings were retrospectively analysed in 39 patients with proven abdominal tuberculosis (TB). The patients were treated over 15 years at a major teaching hospital, Mubarak Al-Kabber Hospital, in Kuwait. The findings included clear or complex ascites with fine strands, loculations and debris. The other findings were lymphadenopathy, bowel wall thickening, omental mass, focal lesions in the liver and spleen and psoas abscess. The sonographic findings in abdominal TB are not specific but may give valuable information to prevent unnecessary laparotomy. PMID:10901897

  12. Role of resting thallium201 perfusion in predicting coronary anatomy, left ventricular wall motion, and hospital outcome in unstable angina pectoris

    SciTech Connect

    Freeman, M.R.; Williams, A.E.; Chisholm, R.J.; Patt, N.L.; Greyson, N.D.; Armstrong, P.W.

    1989-02-01

    We performed quantitative thallium scintigraphy in 66 unstable angina patients, 5.6 +/- 5.1 hours after rest pain, to predict coronary anatomy, left ventricular wall motion, and hospital outcome. Thallium defects and/or washout abnormalities were present in 5 of 10 (50%) patients with coronary stenoses less than 50%, 27 of 33 (82%) patients with coronary stenosis greater than or equal to 50% and no history of previous myocardial infarction, and in 23 of 23 patients (100%) with histories of previous infarction. Defects were uncommon in the territory of vessels with less than 50% (13 of 61, 21%), but significantly more common in the territory of vessels with greater than or equal to 50% stenosis (57 of 137, 42%), p less than 0.005. With the addition of washout abnormalities to defect analysis, sensitivity for detection of coronary stenoses improved to 67% (92 of 137), p less than or equal to 0.005, but specificity fell to 59% (36 of 61), p less than 0.01. Segmental wall motion abnormalities were less common in segments with normal perfusion (21%) or in those with washout abnormalities alone (19%), than in segments with thallium defects (45%, p less than 0.005). Defects in patients with previous infarction were common in both segments, with normal (26 of 66, 40%) or abnormal (24 of 45, 53%) wall motion. Eleven of 18 patients with in-hospital cardiac events, but no history of myocardial infarction, had resting thallium defects, whereas only 8 of 25 patients without cardiac event had thallium defect (p = 0.056).

  13. High efficiency of the spin-orbit torques induced domain wall motion in asymmetric interfacial multilayered Tb/Co wires

    SciTech Connect

    Bang, Do; Awano, Hiroyuki

    2015-05-07

    We investigated current-induced DW motion in asymmetric interfacial multilayered Tb/Co wires for various thicknesses of magnetic and Pt-capping layers. It is found that the driving mechanism for the DW motion changes from interfacial to bulk effects at much thick magnetic layer (up to 19.8 nm). In thin wires, linearly depinning field dependence of critical current density and in-plane field dependence of DW velocity suggest that the extrinsic pinning governs field-induced DW motion and injecting current can be regarded as an effective field. It is expected that the high efficiency of spin-orbit torques in thick magnetic multilayers would have important implication for future spintronic devices based on in-plane current induced-DW motion or switching.

  14. Retrospective analysis of a VACM (vacuum-assisted closure and mesh-mediated fascial traction) treatment manual for temporary abdominal wall closure – results of 58 consecutive patients

    PubMed Central

    Beltzer, Christian; Eisenächer, Alexander; Badendieck, Steffen; Doll, Dietrich; Küper, Markus; Lenz, Stefan; Krapohl, Björn Dirk

    2016-01-01

    Introduction: The optimal treatment concept for temporary abdominal closure (TAC) in critically ill visceral surgery patients with open abdomen (OA) continues to be unclear. The VACM (vacuum-assisted closure and mesh-mediated fascial traction) therapy seems to permit higher delayed primary fascial closure rates (FCR) than other TAC procedures. Material and methods: Patients of our clinic (n=58) who were treated by application of a VAC/VACM treatment manual in the period from 2005 to 2008 were retrospectively analysed. Results: The overall FCR of all patients was 48.3% (95% confidence interval: 34.95–61.78). An FCR of 61.3% was achieved in patients who had a vicryl mesh implanted at the fascial level (VACM therapy) in the course of treatment. Mortality among patients treated with VACM therapy was 45.2% (95% CI: 27.32–63.97). Conclusions: The results of our own study confirm the results of previous studies which showed an acceptable FCR among non-trauma patients who were treated with VACM therapy. VACM therapy currently appears to be the treatment regime of choice for patients with OA requiring TAC. PMID:27547691

  15. Domain-wall motion in ferromagnetic nanowires driven by arbitrary time-dependent fields: an exact result.

    PubMed

    Goussev, Arseni; Robbins, J M; Slastikov, Valeriy

    2010-04-01

    We address the dynamics of magnetic domain walls in ferromagnetic nanowires under the influence of external time-dependent magnetic fields. We report a new exact spatiotemporal solution of the Landau-Lifshitz-Gilbert equation for the case of soft ferromagnetic wires and nanostructures with uniaxial anisotropy. The solution holds for applied fields with arbitrary strength and time dependence. We further extend this solution to applied fields slowly varying in space and to multiple domain walls. PMID:20481956

  16. Current-induced domain wall motion attributed to spin Hall effect and Dzyaloshinsky–Moriya interaction in Pt/GdFeCo (100 nm) magnetic wire

    NASA Astrophysics Data System (ADS)

    Kurokawa, Yuichiro; Kawamoto, Masaya; Awano, Hiroyuki

    2016-07-01

    We investigated the current-induced domain wall motion (CIDWM) in Pt/GdFeCo bilayer wires where the thicknesses of the GdFeCo layer are 110 and 150 nm. We found that the direction of CIDWM in the Pt/GdFeCo wires is the same as the current flow direction. The velocity of the domain wall depends on the in-plane magnetic field. These results indicate that the CIDWM along the current direction in the Pt/GdFeCo wires is probably attributed to the spin Hall effect and Dzyaloshinsky–Moriya interaction. Generally, these effects do not appear in thick magnetic wires because they effectively occur at the interfaces of a heavy metal and magnetic layers. Therefore, these results are interesting phenomena because they probably suggest that the spin Hall effect and Dzyaloshinsky–Moriya interaction in the Pt/GdFeCo wire have an anomalously long-range influence.

  17. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  18. Regional Mapping of Aortic Wall Stress by Using Deformable, Motion-coherent Modeling based on Electrocardiography-gated Multidetector CT Angiography: Feasibility Study.

    PubMed

    Mileto, Achille; Heye, Tobias J; Makar, Ryan A; Hurwitz, Lynne M; Marin, Daniele; Boll, Daniel T

    2016-07-01

    Purpose To investigate the feasibility of deformable, motion-coherent modeling based on electrocardiography-gated multidetector computed tomographic (CT) angiography of the thoracic aorta and to evaluate whether quantifiable information on aortic wall stress as a function of patient-specific cardiovascular parameters can be gained. Materials and Methods For this institutional review board-approved, HIPAA-compliant study, thoracic electrocardiography-gated dual-source multidetector CT angiographic images were used from 250 prospectively enrolled patients (150 men, 100 women; mean age, 79 years). On reconstructed 50-phase CT angiographic images, aortic strain and deformation were determined at seven cardiac and aortic locations. One-way analysis of variance was used by assessing the magnitude for longitudinal and axial strain and axial deformation, as well as time-resolved peak and maxima count for longitudinal strain and axial deformation. Interdependencies between aortic strain and deformation with extracted hemodynamic parameters were evaluated. Results With increasing heart rates, there was a significant decrease in longitudinal strain (P = .009, R(2) = 0.95) and a decrease in the number of longitudinal strain peaks (P < .001, R(2) = 0.79); however, a significant increase in axial deformation (P < .001, R(2) = 0.31) and axial strain (P = .009, R(2) = 0.61) was observed. Increasing aortic blood velocity led to increased longitudinal strain (P = .018, R(2) = 0.42) and longitudinal strain peak counts (P = .011, R(2) = 0.48). Pronounced motion in the longitudinal direction limited motion in the axial plane (P < .019, R(2) = 0.29-0.31). Conclusion The results of this study render a clinical basis and provide proof of principle for the use of deformable, motion-coherent modeling to provide quantitative information on physiological motion of the aorta under various hemodynamic circumstances. (©) RSNA, 2016 Online supplemental material is available for this article

  19. BIOMECHANICS OF ABDOMINAL AORTIC ANEURYSM

    PubMed Central

    Vorp, David A.

    2009-01-01

    Abdominal aortic aneurysm (AAA) is a condition whereby the terminal aorta permanently dilates to dangerous proportions, risking rupture. The biomechanics of AAA has been studied with great interest since aneurysm rupture is a mechanical failure of the degenerated aortic wall and is a significant cause of death in developed countries. In this review article, the importance of considering the biomechanics of AAA is discussed, and then the history and the state-of-the-art of this field is reviewed - including investigations into the biomechanical behavior of AAA tissues, modeling AAA wall stress and factors which influence it, and the potential clinical utility of these estimates in predicting AAA rupture. PMID:17254589

  20. On the motion through a viscous fluid of a spherical particle touching a plane wall: Slip boundary conditions

    SciTech Connect

    Davis, A.M.J.; Kezirian, M.T.; Brenner, H.

    1992-12-31

    Understanding the hydrodynamic forces acting upon immersed particles touching surfaces, is of central importance in clean room technology and a variety of rheological and biological applications. This paper addresses the translation and rotation of a sphere translating and rotating parallel to a nearby plane wall bounding an otherwise quiescent semi-infinite viscous fluid, allowing for slip on the wall and/or the sphere. The motivation for disregarding the classical, no-slip boundary condition on solid surfaces aries from an embarrassing discrepancy between theoretical and observed predictions of the translational velocity of a sphere `rolling` under the influence of gravity down an inclined plane bounding an effectively semi-infinite viscous fluid. According to theory the force and torque on a translating and/or rotating sphere moving parallel to the plane wall become logarithmically infinite with the gap width as the gap between the sphere and well goes to zero. As such, the theoretical conclusion is that the sphere cannot translate down the plane, despite the gravity force that acts to animate it. Experiments, however, reveal that the sphere does, in fact, roll down the plane - at a reproducible mean terminal velocity. In the noninertial, small Reynolds number limit, the experimentally observed drag coefficient was found to be about 8.9 times that given by Stokes law for the unbounded case - thereby suggesting a conventional hydrodynamic wall effect, rather than the logarithmically singular behavior predicted by the theory. It was in an attempt to resolve this glaring contradiction that we have elected here to examine the possible effects of slip.

  1. On the motion through a viscous fluid of a spherical particle touching a plane wall: Slip boundary conditions

    SciTech Connect

    Davis, A.M.J.; Kezirian, M.T.; Brenner, H.

    1992-01-01

    Understanding the hydrodynamic forces acting upon immersed particles touching surfaces, is of central importance in clean room technology and a variety of rheological and biological applications. This paper addresses the translation and rotation of a sphere translating and rotating parallel to a nearby plane wall bounding an otherwise quiescent semi-infinite viscous fluid, allowing for slip on the wall and/or the sphere. The motivation for disregarding the classical, no-slip boundary condition on solid surfaces aries from an embarrassing discrepancy between theoretical and observed predictions of the translational velocity of a sphere rolling' under the influence of gravity down an inclined plane bounding an effectively semi-infinite viscous fluid. According to theory the force and torque on a translating and/or rotating sphere moving parallel to the plane wall become logarithmically infinite with the gap width as the gap between the sphere and well goes to zero. As such, the theoretical conclusion is that the sphere cannot translate down the plane, despite the gravity force that acts to animate it. Experiments, however, reveal that the sphere does, in fact, roll down the plane - at a reproducible mean terminal velocity. In the noninertial, small Reynolds number limit, the experimentally observed drag coefficient was found to be about 8.9 times that given by Stokes law for the unbounded case - thereby suggesting a conventional hydrodynamic wall effect, rather than the logarithmically singular behavior predicted by the theory. It was in an attempt to resolve this glaring contradiction that we have elected here to examine the possible effects of slip.

  2. On the motion through a viscous fluid of a spherical particle touching a plane wall: Slip boundary conditions

    NASA Astrophysics Data System (ADS)

    Davis, A. M. J.; Kezirian, M. T.; Brenner, H.

    Understanding the hydrodynamic forces acting upon immersed particles touching surfaces is of central importance in clean room technology and a variety of rheological and biological applications. This paper addresses the translation and rotation of a sphere translating and rotating parallel to a nearby plane wall bounding an otherwise quiescent semi-infinite viscous fluid, while allowing for slip on the wall and/or the sphere. The motivation for disregarding the classical, no-slip boundary condition on solid surfaces arises from an embarrassing discrepancy between theoretical and observed predictions of the translational velocity of a sphere 'rolling' under the influence of gravity down an inclined plane bounding an effectively semi-infinite viscous fluid. According to theory the force and torque on a translating and/or rotating sphere moving parallel to the plane wall become logarithmically infinite with the gap width as the gap between the sphere and well goes to zero. As such, the theoretical conclusion is that the sphere cannot translate down the plane, despite the gravity force that acts to animate it. Experiments, however, reveal that the sphere does, in fact, roll down the plane--at a reproducible mean terminal velocity. In the noninertial, small Reynolds number limit, the experimentally observed drag coefficient was found to be about 8.9 times that given by Stokes law for the unbounded case. This suggests a conventional hydrodynamic wall effect, rather than the logarithmically singular behavior predicted by the theory. It was in an attempt to resolve this glaring contradiction that we have elected here to examine the possible effects of slip.

  3. Real-time ultrasound-tagging to track the 2D motion of the common carotid artery wall in vivo

    SciTech Connect

    Zahnd, Guillaume; Salles, Sébastien; Liebgott, Hervé; Vray, Didier; Sérusclat, André; Moulin, Philippe

    2015-02-15

    Purpose: Tracking the motion of biological tissues represents an important issue in the field of medical ultrasound imaging. However, the longitudinal component of the motion (i.e., perpendicular to the beam axis) remains more challenging to extract due to the rather coarse resolution cell of ultrasound scanners along this direction. The aim of this study is to introduce a real-time beamforming strategy dedicated to acquire tagged images featuring a distinct pattern in the objective to ease the tracking. Methods: Under the conditions of the Fraunhofer approximation, a specific apodization function was applied to the received raw channel data, in real-time during image acquisition, in order to introduce a periodic oscillations pattern along the longitudinal direction of the radio frequency signal. Analytic signals were then extracted from the tagged images, and subpixel motion tracking of the intima–media complex was subsequently performed offline, by means of a previously introduced bidimensional analytic phase-based estimator. Results: The authors’ framework was applied in vivo on the common carotid artery from 20 young healthy volunteers and 6 elderly patients with high atherosclerosis risk. Cine-loops of tagged images were acquired during three cardiac cycles. Evaluated against reference trajectories manually generated by three experienced analysts, the mean absolute tracking error was 98 ± 84 μm and 55 ± 44 μm in the longitudinal and axial directions, respectively. These errors corresponded to 28% ± 23% and 13% ± 9% of the longitudinal and axial amplitude of the assessed motion, respectively. Conclusions: The proposed framework enables tagged ultrasound images of in vivo tissues to be acquired in real-time. Such unconventional beamforming strategy contributes to improve tracking accuracy and could potentially benefit to the interpretation and diagnosis of biomedical images.

  4. [Crepitant abdominal cellulitis: a rare clinical presentation of sigmoid tumor].

    PubMed

    Chaib, E; Leal, M C; Onofrio, P L; Nahas, P; de Mello, J B

    1990-01-01

    Unusual infections associated with colorectal tumors may, in some instances, be the sole clue to presence of malignancy. The infections are either related to invasion of tissues or organs in close proximity to the tumor or secondary to distant seeding by transient bacteremia arising from necrotic tumors. The authors present one case of spontaneous crepitant cellulitis in the lower abdominal wall, associated with sigmoid tumor. The patient had abdominal pain in the left iliaca fossa, fever and skin necrosis of the lower abdominal wall in the last 4 hours. At surgery they performed debridement and excision of necrotic tissue (lower abdominal wall) and partial sigmoidectomy with sigmoid colostomy. The patient died 9 months after initial surgery. A study of tumor mass revealed an adenocarcinoma. The presence of crepitant cellulitis in a lower abdominal wall should result in a search for bowel perforation. PMID:2151244

  5. Combined subcutaneous, intrathoracic and abdominal splenosis.

    PubMed

    Javadrashid, Reza; Paak, Neda; Salehi, Ahad

    2010-09-01

    We report a case of combined subcutaneous, intrathoracic, and abdominal splenosis who presented with attacks of flushing, tachycardia and vague abdominal pain. The patient's past medical history included a splenectomy due to abdominal trauma and years later, a lung lobectomy due to recurrent pneumonia. An enhancing solid mass adjacent to the upper pole of the left kidney and nodular pleural based lesions in the left hemi-thorax along with nodular lesions in subcutaneous tissue of the left chest wall suggested possible adrenal malignancy with multiple metastases. Histopathologic examination demonstrated benign lesions of ectopic splenic tissue. PMID:20804314

  6. Inversion symmetry of Josephson current as test of chiral domain wall motion in Sr2RuO4

    NASA Astrophysics Data System (ADS)

    Saitoh, Kohta; Kashiwaya, Satoshi; Kashiwaya, Hiromi; Mawatari, Yasunori; Asano, Yasuhiro; Tanaka, Yukio; Maeno, Yoshiteru

    2015-09-01

    Clarifying the chiral domain structure of superconducting Sr2RuO4 has been a long-standing issue in identifying its peculiar topological superconducting state. We evaluated the critical current Ic versus the magnetic field H of Nb/Sr2RuO4 Josephson junctions, changing the junction dimension in expectation of that the number of domains in the junction is controlled. Ic(H ) exhibits a recovery from inversion symmetry breaking to invariance when the dimension is reduced to several microns. This inversion invariant behavior indicates the disappearance of domain walls; thus, the size of a single domain is estimated at approximately several microns.

  7. Abdominal Compartment Syndrome in a Pediatric Patient With Cloacal Exstrophy.

    PubMed

    Cooper, Caleb E; Kennedy, Alfred P; Smith, D Preston

    2016-07-01

    We present a rare complication of abdominal compartment syndrome (ACS) in a child undergoing complex urologic reconstruction. A 10-year-old female born with the abdominal wall defect cloacal exstrophy who had previously undergone multiple abdominal procedures then developed findings consistent with ACS following a complex Mitrofanoff procedure. Although intravesical pressures were not documented because of the nature of her reconstruction, her ACS-type findings were (1) abdominal pain, (2) melena, (3) pulmonary hypoinflation, (4) renal insufficiency, (5) tachycardia, and (6) segmental ischemic small bowel. Management consisted of abdominal decompression, segmental bowel resections, and wound vacuum-assisted-closure management. Patient was eventually discharged home. PMID:26921644

  8. Design and evaluation of a 67% area-less 64-bit parallel reconfigurable 6-input nonvolatile logic element using domain-wall motion devices

    NASA Astrophysics Data System (ADS)

    Suzuki, Daisuke; Natsui, Masanori; Mochizuki, Akira; Hanyu, Takahiro

    2014-01-01

    A 6-input nonvolatile logic element (NV-LE) using domain-wall motion (DWM) devices is presented for low-power and real-time reconfigurable logic LSI applications. Because the write current path of a DWM device is separated from its read current path and the resistance value of the write current path is quite small, multiple DWM devices can be reprogrammed in parallel, thus affording real-time logic-function reconfiguration within a few nanoseconds. Moreover, by merging a circuit component between combinational and sequential logic functions, transistor counts can be minimized. As a result, 2-ns 64-bit-parallel circuit reconfiguration is realized by the proposed 6-input NV-LE with 67% lesser area than a conventional CMOS-based alternative, with a simulation program with integrated circuit emphasis (SPICE) simulation under a 90 nm CMOS/MTJ technologies.

  9. An In Vitro Comparative Study of Intracanal Fluid Motion and Wall Shear Stress Induced by Ultrasonic and Polymer Rotary Finishing Files in a Simulated Root Canal Model

    PubMed Central

    Koch, Jon; Borg, John; Mattson, Abby; Olsen, Kris; Bahcall, James

    2012-01-01

    Objective. This in vitro study compared the flow pattern and shear stress of an irrigant induced by ultrasonic and polymer rotary finishing file activation in an acrylic root canal model. Flow visualization analysis was performed using an acrylic canal filled with a mixture of distilled water and rheoscopic fluid. The ultrasonic and polymer rotary finishing file were separately tested in the canal and activated in a static position and in a cyclical axial motion (up and down). Particle movement in the fluid was captured using a high-speed digital camera and DaVis 7.1 software. The fluid shear stress analysis was performed using hot film anemometry. A hot-wire was placed in an acrylic root canal and the canal was filled with distilled water. The ultrasonic and polymer rotary finishing files were separately tested in a static position and in a cyclical axial motion. Positive needle irrigation was also tested separately for fluid shear stress. The induced wall shear stress was measured using LabVIEW 8.0 software. PMID:22461994

  10. Characterization of Pancreatic Tumor Motion Using Cine MRI: Surrogates for Tumor Position Should Be Used With Caution

    SciTech Connect

    Feng, Mary Balter, James M.; Normolle, Daniel; Adusumilli, Saroja; Cao Yue; Chenevert, Thomas L.; Ben-Josef, Edgar

    2009-07-01

    Purpose: Our current understanding of intrafraction pancreatic tumor motion due to respiration is limited. In this study, we characterized pancreatic tumor motion and evaluated the application of several radiotherapy motion management strategies. Methods and Materials: Seventeen patients with unresectable pancreatic cancer were enrolled in a prospective internal review board-approved study and imaged during shallow free-breathing using cine MRI on a 3T scanner. Tumor borders were agreed on by a radiation oncologist and an abdominal MRI radiologist. Tumor motion and correlation with the potential surrogates of the diaphragm and abdominal wall were assessed. These data were also used to evaluate planning target volume margin construction, respiratory gating, and four-dimensional treatment planning for pancreatic tumors. Results: Tumor borders moved much more than expected. To provide 99% geometric coverage, margins of 20 mm inferiorly, 10 mm anteriorly, 7 mm superiorly, and 4 mm posteriorly are required. Tumor position correlated poorly with diaphragm and abdominal wall position, with patient-level Pearson correlation coefficients of -0.18-0.43. Sensitivity and specificity of gating with these surrogates was also poor, at 53%-68%, with overall error of 35%-38%, suggesting that the tumor may be underdosed and normal tissues overdosed. Conclusions: Motion of pancreatic tumor borders is highly variable between patients and larger than expected. There is substantial deformation with breathing, and tumor border position does not correlate well with abdominal wall or diaphragmatic position. Current motion management strategies may not account fully for tumor motion and should be used with caution.

  11. Asymmetric grazing incidence small angle x-ray scattering and anisotropic domain wall motion in obliquely grown nanocrystalline Co films.

    PubMed

    Quirós, C; Peverini, L; Díaz, J; Alija, A; Blanco, C; Vélez, M; Robach, O; Ziegler, E; Alameda, J M

    2014-08-22

    Strong asymmetries have been observed in grazing incidence small angle x-ray scattering (GISAXS) in situ patterns obtained from 30 nm-thick nanocrystalline Co films prepared by oblique sputtering (15°-75° off-sample normal). These asymmetries have been qualitatively simulated by a simple model consisting of an ensemble of 8 nm-wide inclined Co nanocolumns. It is found that narrow inclined features appear in the diffuse background resembling those characteristic of faceted systems, which can be used to obtain straightforward non-destructive estimations of buried nanocolumnar grains inclination, even for oblique angles below 45°, when the stronger and broader asymmetric features of the pattern are not yet fully formed. Furthermore, using magneto-optical microscopy, a marked change in the magnetic domain's nucleation and growth process has been observed in the sample prepared at 75°, with the stronger GISAXS asymmetries. Easy axis magnetization reversal starts by a random and homogeneous nucleation of small (∼μm) elongated domains aligned with the nanocolumn's long axis and proceeds through the preferred propagation of head-to-head domain walls (DWs) along the applied field direction. This peculiar magnetic behavior indicates that the strongly anisotropic nanostructuring created by the oblique growth process is equivalent, from a magnetic point of view, to an array of self-assembled buried nanowires. These results show how GISAXS and magneto-optical microscopy can be combined as a powerful tool for correlating the morphology and magnetism of thin nanostructured systems. PMID:25074483

  12. Merkel cell carcinoma of the abdominal wall

    PubMed Central

    Gaopande, Vandana L.; Joshi, Avinash R.; Khandeparkar, Siddhi G. S.; Deshmukh, Sanjay D.

    2015-01-01

    Merkel cell carcinoma also known as neuroendocrine carcinoma of the skin is a very rare skin tumor. It commonly presents in the old age and the common sites are head, neck and extremities. The diagnosis requires histopathological examination with immunohistochemical correlation. We report a case of Merkel cell carcinoma stage IIIB with bilateral inguinal lymphadenopathy that on FNAB showed metastatic deposits of the tumor. PMID:26225333

  13. Component Separation for Complex Abdominal Wall Reconstruction

    MedlinePlus Videos and Cool Tools

    ... to you from Albany Medical Center in Albany, New York. In just moments, you'll learn how ... what we'll do is we'll take new 2-0s, and if we can kind of ... reconstruction performed from Albany Medical Center in Albany, New York. OR-Live makes it easy for you ...

  14. Contributions of domain wall motion to complex electromechanical coefficients of 0.62Pb(Mg1∕3Nb2∕3)O3–0.38PbTiO3 crystals

    PubMed Central

    Wang, Zhu; Zhang, Rui; Sun, Enwei; Cao, Wenwu

    2010-01-01

    The loss behavior of 0.62Pb(Mg1∕3Nb2∕3)O3–0.38PbTiO3 (PMN-38%PT) ferroelectric single crystal poled along [001]c was investigated. It was found that the complex electromechanical coefficients and loss factors change dramatically at the coercive field Ec around 250 V∕mm, representing the intrinsic switching barrier. Since the energy loss is related to the domain wall motion, the imaginary parts of the electromechanical coefficients can be used to study the degree of domain wall motions in relaxor-based ferroelectric single crystals. Experimental results indicate that for this system, domain wall motion contributes significantly to the imaginary parts of electromechanical coefficients. In addition, [001]c poled PMN-38%PT single crystals have much larger mechanical loss factor compared to that of conventional single crystal like LiNbO3. This phenomenon is proved to be closely related to 90° domain wall motion in this crystal system. PMID:20145700

  15. Abdominal aortic aneurysm

    MedlinePlus

    ... to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ... blood pressure Male gender Genetic factors An abdominal aortic aneurysm is most often seen in males over age ...

  16. Abdominal x-ray

    MedlinePlus

    ... More Abdominal aortic aneurysm Abdominal pain Acute cholecystitis Acute kidney failure Addison disease Adenomyosis Annular pancreas Aplastic anemia Appendicitis Ascariasis Atheroembolic renal disease Biliary atresia Blind loop syndrome Cholangitis Chronic ...

  17. Lateral abdominal muscle size at rest and during abdominal drawing-in manoeuvre in healthy adolescents.

    PubMed

    Linek, Pawel; Saulicz, Edward; Wolny, Tomasz; Myśliwiec, Andrzej; Kokosz, Mirosław

    2015-02-01

    Lateral abdominal wall muscles in children and adolescents have not been characterised to date. In the present report, we examined the reliability of the ultrasound measurement and thickness of the oblique external muscle (OE), oblique internal muscle (OI) and transverse abdominal muscle (TrA) at rest and during abdominal drawing-in manoeuvre (ADIM) on both sides of the body in healthy adolescents. We also determined possible differences between boys and girls and defined any factors-such as body mass, height and BMI-that may affect the thickness of the abdominal muscles. B-mode ultrasound was used to assess OE, OI and TrA on both sides of the body in the supine position. Ultrasound measurements at rest and during ADIM were reliable in this age group (ICC3,3 > 0.92). OI was always the thickest and TrA the thinnest muscle on both sides of the body. In this group, an identical pattern of the contribution of the individual muscles to the structure of the lateral abdominal wall (OI > OE > TrA) was observed. At rest and during ADIM, no statistically significant side-to-side differences were demonstrated in either gender. The body mass constitutes between 30% and <50% of the thickness differences in all muscles under examination at rest and during ADIM. The structure of lateral abdominal wall in adolescents is similar to that of adults. During ADIM, the abdominal muscles in adolescents react similarly to those in adults. This study provided extensive information regarding the structure of the lateral abdominal wall in healthy adolescents. PMID:25088309

  18. Abdominal Circulatory Interactions.

    PubMed

    Dagar, Gaurav; Taneja, Amit; Nanchal, Rahul S

    2016-04-01

    The abdominal compartment is separated from the thoracic compartment by the diaphragm. Under normal circumstances, a large portion of the venous return crosses the splanchnic and nonsplanchnic abdominal regions before entering the thorax and the right side of the heart. Mechanical ventilation may affect abdominal venous return independent of its interactions at the thoracic level. Changes in pressure in the intra-abdominal compartment may have important implications for organ function within the thorax, particularly if there is a sustained rise in intra-abdominal pressure. It is important to understand the consequences of abdominal pressure changes on respiratory and circulatory physiology. This article elucidates important abdominal-respiratory-circulatory interactions and their clinical effects. PMID:27016167

  19. [The patient with intra-abdominal hypertension].

    PubMed

    Sakka, Samir G

    2016-01-01

    An intra-abdominal hypertension (IAH) defined as a pathological increase in intra-abdominal pressure (IAP) is commonly found on ICU admission or during the ICU stay. Several studies confirmed that an IAH is an independent predictor for mortality of critically ill patients. The abdominal compartment syndrome (ACS) which is defined as a sustained IAP>20 mmHg (with or without an abdominal perfusion pressure [APP]<60mmHg) that is associated with new organ dysfunction or failure has a mortality of up to 60%. In general, an IAH may be induced by several intra-abdominal as well as extra-abdominal conditions. Reduced abdominal wall compliance, intra-abdominal pathologies (either of the peritoneal space or parenchymateous organs) may lead to an IAH. Most commonly, intra-abdominal infections and/or sepsis and severe trauma or burns are predisposing for an IAH. An early sign may be a decrease in urinary output. The effects of an increased IAP on cardiovascular function are well recognized and include negative effects on preload, afterload and contractility. However, all other compartments of the body may be affected by an IAH. Thus, by an increase of the respective compartment pressure, e.g. intracranial pressure, a poly-compartment syndrome may result. Adequate prevention, a forward-looking strategy, and objective techniques for measurement of IAP are required to avoid or early detect an IAH or ACS. Finally, an immediate and consequent interdisciplinary management using conservative, interventional and operative options are necessary to solve an IAH or ACS. PMID:26863642

  20. Laparoscopic Bullet Removal in a Penetrating Abdominal Gunshot.

    PubMed

    Stefanou, Christos; Zikos, Nicolaos; Pappas-Gogos, George; Koulas, Spyridon; Tsimoyiannis, Ioannis

    2016-01-01

    Penetrating abdominal trauma has been traditionally treated by exploratory laparotomy. Nowadays laparoscopy has become an accepted practice in hemodynamically stable patient without signs of peritonitis. We report a case of a lower anterior abdominal gunshot patient treated laparoscopically. A 32-year-old male presented to the Emergency Department with complaint of gunshot penetrating injury at left lower anterior abdominal wall. The patient had no symptoms or obvious bleeding and was vitally stable. On examination we identified 1 cm diameter entry wound at the left lower abdominal wall. The imaging studies showed the bullet in the peritoneal cavity but no injured intraperitoneal and retroperitoneal viscera. We decided to remove the bullet laparoscopically. Twenty-four hours after the intervention the patient was discharged. The decision for managing gunshot patients should be based on clinical and diagnostic findings. Anterior abdominal injuries in a stable patient without other health problems can be managed laparoscopically. PMID:27525150

  1. Laparotomy for blunt abdominal trauma-some uncommon indications.

    PubMed

    Dharap, Satish B; Noronha, Jarin; Kumar, Vineet

    2016-01-01

    Trauma laparotomy after blunt abdominal trauma is conventionally indicated for patients with features of hemodynamic instability and peritonitis to achieve control of hemorrhage and control of spillage. In addition, surgery is clearly indicated for the repair of posttraumatic diaphragmatic injury with herniation. Some other indications for laparotomy have been presented and discussed. Five patients with blunt abdominal injury who underwent laparotomy for nonroutine indications have been presented. These patients were hemodynamically stable and had no overt signs of peritonitis. Three patients had solid organ (spleen, kidney) infarction due to posttraumatic occlusion of the blood supply. One patient had mesenteric tear with internal herniation of bowel loops causing intestinal obstruction. One patient underwent surgery for traumatic abdominal wall hernia. In addition to standard indications for surgery in blunt abdominal trauma, laparotomy may be needed for vascular thrombosis of end arteries supplying solid organs, internal or external herniation through a mesenteric tear or anterior abdominal wall musculature, respectively. PMID:26957824

  2. Laparoscopic Bullet Removal in a Penetrating Abdominal Gunshot

    PubMed Central

    Koulas, Spyridon; Tsimoyiannis, Ioannis

    2016-01-01

    Penetrating abdominal trauma has been traditionally treated by exploratory laparotomy. Nowadays laparoscopy has become an accepted practice in hemodynamically stable patient without signs of peritonitis. We report a case of a lower anterior abdominal gunshot patient treated laparoscopically. A 32-year-old male presented to the Emergency Department with complaint of gunshot penetrating injury at left lower anterior abdominal wall. The patient had no symptoms or obvious bleeding and was vitally stable. On examination we identified 1 cm diameter entry wound at the left lower abdominal wall. The imaging studies showed the bullet in the peritoneal cavity but no injured intraperitoneal and retroperitoneal viscera. We decided to remove the bullet laparoscopically. Twenty-four hours after the intervention the patient was discharged. The decision for managing gunshot patients should be based on clinical and diagnostic findings. Anterior abdominal injuries in a stable patient without other health problems can be managed laparoscopically. PMID:27525150

  3. Cardiopulmonary monitoring in intra-abdominal hypertension.

    PubMed

    Malbrain, Manu L N G; Ameloot, Koen; Gillebert, Carl; Cheatham, Michael L

    2011-07-01

    Cardiopulmonary dysfunction and failure are commonly encountered in the patient with intra-abdominal hypertension (IAH) or abdominal compartment syndrome. Accurate assessment and optimization of preload, contractility, and afterload in conjunction with appropriate goal-directed resuscitation and assessment of fluid responsiveness are essential to restore end-organ perfusion. In patients with IAH, the traditional "barometric" preload indicators such as pulmonary artery occlusion pressure and central venous pressure are erroneously increased. Volumetric monitoring techniques have been proven to be superior in directing the appropriate resuscitation together with targeted abdominal perfusion pressure. If such limitations are not recognized, misinterpretation of the patient's cardiac status is likely, resulting in inappropriate and potentially detrimental therapy. IAH also markedly affects the mechanical properties of the chest wall and consequently also the respiratory function. Altered mechanical properties of the chest wall may limit ventilation, influence the work of breathing, affect the interaction between the respiratory muscles, hasten the development of respiratory failure, and interfere with gas exchange. Pulmonary monitoring is important to understand the relationships between intra-abdominal pressure and chest wall mechanics and the impact of IAH on ventilator-induced lung injury, lung distention, recruitment, and lung edema. PMID:21944448

  4. Abdominal aortic aneurysm.

    PubMed

    Keisler, Brian; Carter, Chuck

    2015-04-15

    Abdominal aortic aneurysm refers to abdominal aortic dilation of 3.0 cm or greater. The main risk factors are age older than 65 years, male sex, and smoking history. Other risk factors include a family history of abdominal aortic aneurysm, coronary artery disease, hypertension, peripheral artery disease, and previous myocardial infarction. Diagnosis may be made by physical examination, an incidental finding on imaging, or ultrasonography. The U.S. Preventive Services Task Force released updated recommendations for abdominal aortic aneurysm screening in 2014. Men 65 to 75 years of age with a history of smoking should undergo one-time screening with ultrasonography based on evidence that screening will improve abdominal aortic aneurysm-related mortality in this population. Men in this age group without a history of smoking may benefit if they have other risk factors (e.g., family history of abdominal aortic aneurysm, other vascular aneurysms, coronary artery disease). There is inconclusive evidence to recommend screening for abdominal aortic aneurysm in women 65 to 75 years of age with a smoking history. Women without a smoking history should not undergo screening because the harms likely outweigh the benefits. Persons who have a stable abdominal aortic aneurysm should undergo regular surveillance or operative intervention depending on aneurysm size. Surgical intervention by open or endovascular repair is the primary option and is typically reserved for aneurysms 5.5 cm in diameter or greater. There are limited options for medical treatment beyond risk factor modification. Ruptured abdominal aortic aneurysm is a medical emergency presenting with hypotension, shooting abdominal or back pain, and a pulsatile abdominal mass. It is associated with high prehospitalization mortality. Emergent surgical intervention is indicated for a rupture but has a high operative mortality rate. PMID:25884861

  5. Abdominal intrauterine vacuum aspiration.

    PubMed

    Tjalma, W A A

    2014-01-01

    Evaluating and "cleaning" of the uterine cavity is probably the most performed operation in women. It is done for several reasons: abortion, evaluation of irregular bleeding in premenopausal period, and postmenopausal bleeding. Abortion is undoubtedly the number one procedure with more than 44 million pregnancies terminated every year. This procedure should not be underestimated and a careful preoperative evaluation is needed. Ideally a sensitive pregnancy test should be done together with an ultrasound in order to confirm a uterine pregnancy, excluding extra-uterine pregnancy, and to detect genital and/or uterine malformations. Three out of four abortions are performed by surgical methods. Surgical methods include a sharp, blunt, and suction curettage. Suction curettage or vacuum aspiration is the preferred method. Despite the fact that it is a relative safe procedure with major complications in less than one percent of cases, it is still responsible for 13% of all maternal deaths. All the figures have not declined in the last decade. Trauma, perforation, and bleeding are a danger triage. When there is a perforation, a laparoscopy should be performed immediately, in order to detect intra-abdominal lacerations and bleeding. The bleeding should be stopped as soon as possible in order to not destabilize the patient. When there is a perforation in the uterus, this "entrance" can be used to perform the curettage. This is particularly useful if there is trauma of the isthmus and uterine wall, and it is difficult to identify the uterine canal. A curettage is a frequent performed procedure, which should not be underestimated. If there is a perforation in the uterus, then this opening can safely be used for vacuum aspiration. PMID:25134300

  6. [Abdominal pregnancy, institutional experience].

    PubMed

    Bonfante Ramírez, E; Bolaños Ancona, R; Simón Pereyra, L; Juárez García, L; García-Benitez, C Q

    1998-07-01

    Abdominal pregnancy is a rare entity, which has been classified as primary or secondary by Studiford criteria. A retrospective study, between January 1989 and December 1994, realized at Instituto Nacional de Perinatología, found 35,080 pregnancies, from which 149 happened to be ectopic, and 6 of them were abdominal. All patients belonged to a low income society class, age between 24 and 35 years, and average of gestations in 2.6. Gestational age varied from 15 weeks to 32.2 weeks having only one delivery at term with satisfactory postnatal evolution. One patient had a recurrent abdominal pregnancy, with genital Tb as a conditional factor. Time of hospitalization varied from 4 to 5 days, and no further patient complications were reported. Fetal loss was estimated in 83.4%. Abdominal pregnancy is often the sequence of a tubarian ectopic pregnancy an when present, it has a very high maternal mortality reported in world literature, not found in this study. The stated frequency of abdominal pregnancy is from 1 of each 3372, up to 1 in every 10,200 deliveries, reporting in the study 1 abdominal pregnancy in 5846 deliveries. The study had two characteristic entities one, the recurrence and two, the delivery at term of one newborn. Abdominal pregnancy accounts for 4% of all ectopic pregnancies. Clinical findings in abdominal pregnancies are pain, transvaginal bleeding and amenorrea, being the cardinal signs of ectopic pregnancy. PMID:9737070

  7. Recurrent Abdominal Pain

    ERIC Educational Resources Information Center

    Banez, Gerard A.; Gallagher, Heather M.

    2006-01-01

    The purpose of this article is to provide an empirically informed but clinically oriented overview of behavioral treatment of recurrent abdominal pain. The epidemiology and scope of recurrent abdominal pain are presented. Referral process and procedures are discussed, and standardized approaches to assessment are summarized. Treatment protocols…

  8. [Influences of chest deformation by upper abdominal retractor on respiratory system impedance during abdominal surgery].

    PubMed

    Oka, T; Ozawa, Y; Sato, J

    1999-02-01

    The present study was carried out to clarify the effects of chest deformation by upper abdominal retractor on respiratory system impedance during abdominal surgery. We measured the impedances of respiratory system (RS), lung, and chest wall (CW) in nine anesthetized paralyzed subjects employing a pseudorandom noise forced volume oscillation technique. These measurements were performed before and after the lifting chest wall by upper abdominal retractor. The effects of chest deformation was significant on the impedances of RS, lung, while no discernible effect was found in CW impedance. Lifting chest wall decreased RS resistance which was totally accounted for by the decrease in lung resistance, whereas the lifting did not affect reactance in either RS or lung. The mathematical modeling showed the significant lifting effect on the resistance of the parenchyma. In conclusion, change in RS mechanics produced by chest deformation by upper abdominal retractor is dominated in lung but not in CW. Among the lung mechanical components, parenchyma is the primary site of the lifting effect. PMID:10087819

  9. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X- ... use high frequency sound waves to produce an image and do not expose the individual to radiation. ...

  10. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  11. Abdominal exploration - series (image)

    MedlinePlus

    ... surgical exploration of the abdomen, also called an exploratory laparotomy, may be recommended when there is abdominal ... blunt trauma"). Diseases that may be discovered by exploratory laparotomy include: inflammation of the appendix (acute appendicitis) ...

  12. Abdominal aortic aneurysm

    MedlinePlus

    ... main blood vessel that supplies blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs ... dissection). Symptoms of rupture include: Pain in the abdomen or back. The pain may be severe, sudden, ...

  13. Abdominal x-ray

    MedlinePlus

    An abdominal x-ray is an imaging test to look at organs and structures in the abdomen. Organs include the spleen, stomach, and intestines. When the test is done to look at the bladder and kidney structures, ...

  14. Abdominal aortic aneurysm.

    PubMed

    Setacci, Francesco; Galzerano, Giuseppe; De Donato, Gianmarco; Benevento, Domenico; Guerrieri, Massimiliano W; Ruzzi, Umberto; Borrelli, Maria P; Setacci, Carlo

    2016-02-01

    Endovascular repair of abdominal aortic aneurysms has become a milestone in the treatment of patients with abdominal aortic aneurysm. Technological improvement allows treatment in more and more complex cases. This review summarizes all grafts available on the market. A complete review of most important trial on this topic is provided to the best of our knowledge, and technical tips and tricks for standard cases are also included. PMID:26771730

  15. Abdominal compartment syndrome (ACS) in a severely burned patient.

    PubMed

    Kollias, S; Stampolidis, N; Kourakos, P; Mantzari, E; Koupidis, S; Tsaousi, S; Dimitrouli, A; Atiyeh, B; Castana, O

    2015-03-31

    Abdominal compartment syndrome (ACS) occurs when increasing intra abdominal-pressure (IAP) reduces blood flow to abdominal organs. This results in impairment of pulmonary, cardiovascular, renal, hepatic, central nervous system and gastro-intestinal (gi) function, causing multiple organ dysfunction syndrome and death. The significant prognostic value of elevated intra-abdominal pressure has prompted many intensive care units to adopt measurement of this physiologic parameter as a routine vital sign in patients at risk. ACS generally occurs in patients who are critically ill due to any of a wide variety of medical and surgical conditions. it has been recently described as a rare complication of burn injury. it is fundamental to: 1) recognize IAP and ACS; 2) resuscitate effectively; and 3) prevent the development IAP-induced end-organ dysfunction and failure. We present our recent experience with one patient suffering from ACS secondary to burn injury and the physiologic results of abdominal wall escharotomy. PMID:26668555

  16. Abdominal compartment syndrome (ACS) in a severely burned patient

    PubMed Central

    kollias, S.; Stampolidis, N.; kourakos, P.; Mantzari, E.; Koupidis, S.; Tsaousi, S.; Dimitrouli, A.; Atiyeh, B.; Castana, O.

    2015-01-01

    Summary Abdominal compartment syndrome (ACS) occurs when increasing intra abdominal-pressure (IAP) reduces blood flow to abdominal organs. This results in impairment of pulmonary, cardiovascular, renal, hepatic, central nervous system and gastro-intestinal (gi) function, causing multiple organ dysfunction syndrome and death. The significant prognostic value of elevated intra-abdominal pressure has prompted many intensive care units to adopt measurement of this physiologic parameter as a routine vital sign in patients at risk. ACS generally occurs in patients who are critically ill due to any of a wide variety of medical and surgical conditions. it has been recently described as a rare complication of burn injury. it is fundamental to: 1) recognize IAP and ACS; 2) resuscitate effectively; and 3) prevent the development IAP-induced end-organ dysfunction and failure. We present our recent experience with one patient suffering from ACS secondary to burn injury and the physiologic results of abdominal wall escharotomy. PMID:26668555

  17. Extensive domain wall motion and deaging resistance in morphotropic 0.55Bi(Ni{sub 1/2}Ti{sub 1/2})O{sub 3}–0.45PbTiO{sub 3} polycrystalline ferroelectrics

    SciTech Connect

    Tutuncu, Goknur; Fan, Longlong; Chen, Jun; Xing, Xianran; Jones, Jacob L.

    2014-03-31

    Domain wall motion is known as a major source of extrinsic contributions to the dielectric and piezoelectric properties of ferroelectric materials. In the present work, we report the extent of non-180° domain wall motion during strong and weak electric field amplitudes in situ using time-resolved, high-energy X-ray diffraction in the ferroelectric morphotropic phase boundary composition 0.55Bi(Ni{sub 1/2}Ti{sub 1/2})O{sub 3}–0.45PbTiO{sub 3} (BNT-45PT). After application of strong electric fields, two phases are shown to coexist. In the tetragonal phase of this material, the extent of 90° domain wall motion is significant and the domain alignment is nearly saturated. Weak (subswitching) cyclic electric fields are then also shown to induce domain wall motion. Deaging, or the progressive loss of preferred domain orientation during sequentially increasing field amplitudes, is notably low in these materials, showing that the initial domain alignment is strongly stabilized. Overall, the in situ measurements reveal that domain wall motion significantly impacts the structure and properties of BNT-45PT and reinforces the importance of understanding domain wall motion contributions to the physical properties of ferroelectrics.

  18. Abdominal Dual Energy Imaging

    NASA Astrophysics Data System (ADS)

    Sommer, F. Graham; Brody, William R.; Cassel, Douglas M.; Macovski, Albert

    1981-11-01

    Dual energy scanned projection radiography of the abdomen has been performed using an experimental line-scanned radiographic system. Digital images simultaneously obtained at 85 and 135 kVp are combined, using photoelectric/Compton decomposition algorithms to create images from which selected materials are cancelled. Soft tissue cancellation images have proved most useful in various abdominal imaging applications, largely due to the elimination of obscuring high-contrast bowel gas shadows. These techniques have been successfully applied to intravenous pyelography, oral cholecystography, intravenous abdominal arteriog-raphy and the imaging of renal calculi.

  19. The Acute Abdominal Aorta.

    PubMed

    Mellnick, Vincent M; Heiken, Jay P

    2015-11-01

    Acute disorders of the abdominal aorta are potentially lethal conditions that require prompt evaluation and treatment. Computed tomography (CT) is the primary imaging method for evaluating these conditions because of its availability and speed. Volumetric CT acquisition with multiplanar reconstruction and three-dimensional analysis is now the standard technique for evaluating the aorta. MR imaging may be useful for select applications in stable patients in whom rupture has been excluded. Imaging is indispensable for diagnosis and treatment planning, because management has shifted toward endoluminal repair. Acute abdominal aortic conditions most commonly are complications of aneurysms and atherosclerosis. PMID:26526434

  20. Abdominal Vascular Catastrophes.

    PubMed

    Singh, Manpreet; Koyfman, Alex; Martinez, Joseph P

    2016-05-01

    Abdominal vascular catastrophes are among the most challenging and time sensitive for emergency practitioners to recognize. Mesenteric ischemia remains a highly lethal entity for which the history and physical examination can be misleading. Laboratory tests are often unhelpful, and appropriate imaging must be quickly obtained. A multidisciplinary approach is required to have a positive impact on mortality rates. Ruptured abdominal aortic aneurysm likewise may present in a cryptic fashion. A specific type of ruptured aneurysm, the aortoenteric fistula, often masquerades as the more common routine gastrointestinal bleed. The astute clinician recognizes that this is a more lethal variant of gastrointestinal hemorrhage. PMID:27133247

  1. Abdominal Aortic Aneurysms

    PubMed Central

    Fortner, George; Johansen, Kaj

    1984-01-01

    Aneurysms are common in our increasingly elderly population, and are a major threat to life and limb. Until the advent of vascular reconstructive techniques, aneurysm patients were subject to an overwhelming risk of death from exsanguination. The first successful repair of an abdominal aortic aneurysm using an interposed arterial homograft was reported by Dubost in 1952. A milestone in the evolution of vascular surgery, this event and subsequent diagnostic, operative and prosthetic graft refinements have permitted patients with an unruptured abdominal aortic aneurysm to enjoy a better prognosis than patients with almost any other form of major systemic illness. Images PMID:6702193

  2. Does an expanding fetal abdominal mass produce pulmonary hypoplasia?

    PubMed

    Sauer, L; Harrison, M R; Flake, A W; Krummel, T R

    1987-06-01

    Fetal pulmonary hypoplasia has been related to multiple factors. In an effort to define which fetuses may benefit from prenatal intervention to prevent or reverse pulmonary hypoplasia, we studied the relative contribution of an enlarging abdominal mass in the fetus. We produced abdominal masses in fetal rabbits at 24 days gestation by two methods. In one group, a small cylindrical chip of Takasen, (a synthetic polymer that expands to 50 times its size in 1 week; Grobeast, Pop Art Co, Cleveland, OH) was inserted into the peritoneal cavity of the fetal rabbit; in another group, the bladder neck was obstructed with a surgical clip. Amniotic fluid volume was restored at the surgical procedure. Sham-operated littermates served as controls. At cesarean delivery on day 30, fetal lung, liver, and body weights were measured, and the abdominal masses were quantitated by volume displacement of the removed mass or bladder. In both groups large abdominal masses of comparable size were produced. Newborns with the synthetic abdominal mass did not have significant pulmonary hypoplasia, but often had a prune belly deformity of the abdominal wall, whereas newborns with bladder obstruction had significant pulmonary hypoplasia. Liver weight was not significantly affected. We conclude that a fetal abdominal mass does not independently produce pulmonary hypoplasia, possibly because the "mass effect" is relieved by distension of the abdominal wall rather than elevation of the diaphragm; the pulmonary hypoplasia that occurs in bladder outlet obstruction is probably due to the associated oligohydramnios rather than the mass effect of the dilated urinary tract; and prenatal decompression of an abdominal mass or dilated urinary tract is not justified to prevent pulmonary hypoplasia in the absence of oligohydramnios. PMID:3612441

  3. Characteristics of colorectal cancer diagnosed with screening abdominal ultrasonography

    PubMed Central

    TOMIZAWA, MINORU; SHINOZAKI, FUMINOBU; HASEGAWA, RUMIKO; FUGO, KAZUNORI; SHIRAI, YOSHINORI; MOTOYOSHI, YASUFUMI; SUGIYAMA, TAKAO; YAMAMOTO, SHIGENORI; KISHIMOTO, TAKASHI; ISHIGE, NAOKI

    2016-01-01

    Patient records were retrospectively analyzed to elucidate the characteristics of patients with colorectal cancer (CRC) diagnosed with screening abdominal ultrasound (US). Patients diagnosed with CRC using abdominal US [localized irregular wall thickening (W) or a hypoechoic mass with a hyperechoic mass (M)] were enrolled. The patients were subjected to colonoscopy and treated surgically between March, 2010 and January, 2015. A total of 5 men (aged 74.0±0.8 years) and 10 women (aged 73.0±12.0 years) were analyzed. Stratification was analyzed with abdominal US. The threshold value of wall thickness to diagnose CRC was investigated with receiver operating characteristic (ROC) curve analysis. The average wall thickness was 2.8±0.4 mm in the surrounding normal tissue and 12.7±5.2 mm in CRC (one-way analysis of variance, P<0.0001). The wall was significantly thicker in CRC compared with the normal colonic wall. The calculated threshold value was 4.3 mm for the diagnosis of CRC. Stratification was preserved in W, while it was lost in M (Chi-squared test, P=0.0196). The hemoglobin concentration was lower, while the C-reactive protein, carcinoembryonic antigen and carbohydrate antigen 19-9 levels were elevated above normal values. The threshold value was 4.3 mm for the diagnosis of CRC with abdominal US. PMID:27330768

  4. Application of real-time, stroboscopic x-ray diffraction with dynamical mechanical analysis to characterize the motion of ferroelastic domain walls

    NASA Astrophysics Data System (ADS)

    Harrison, Richard J.; Redfern, Simon A. T.; Buckley, Andrew; Salje, Ekhard K. H.

    2004-02-01

    The dynamic response of ferroelastic twins to an alternating stress has been studied in situ at high temperature using a stroboscopic x-ray diffractometer and combined dynamical mechanical analyzer (XRD-DMA). The XRD-DMA is designed to allow x-ray rocking curves to be collected while the sample is undergoing simultaneous dynamical mechanical analysis in three-point-bend geometry. The detection of diffracted x-rays is synchronized with the applied load, so that rocking curves corresponding to different parts of the dynamic load cycle can be obtained separately. The technique is applied to single-crystal LaAlO3, which undergoes a cubic to rhombohedral phase transition at 550 °C, leading to the generation of characteristic "chevron" twins. The rocking-curve topology is calculated as a function of crystal orientation for each chevron type. Systematic changes in the rocking curves during heating and cooling under dynamic load demonstrate a clear preference for chevrons containing {100}pc walls perpendicular to the sample surface and {110}pc walls oriented at 45° to the sample surface. These domain walls are oriented favorably with respect to the applied stress (i.e., they separate domains with contrasting components of spontaneous strain parallel to the sample length). Below 200 °C, the superelastic strain is accommodated by rapid advancement/retraction of vertical {100}pc needle domains, with little effect on the dynamic rocking curves. Above 200 °C, a dynamic shift in peak position between rocking curves measured at the maximum and minimum applied loads is detected. The onset of a dynamic response correlates with the loss of the {100}pc needle domains and the transformation of the microstructure to 45° {110}pc walls. Superelastic strain is then accommodated by domain wall displacement/rotation, causing the wall to sweep back and forth across the x-ray beam and diffraction to occur from alternate domains at the maximum and minimum points of the stress cycle. A

  5. Abdominal closure using nonabsorbable mesh after massive resuscitation prevents abdominal compartment syndrome and gastrointestinal fistula.

    PubMed

    Ciresi, D L; Cali, R F; Senagore, A J

    1999-08-01

    Patients who receive high-volume resuscitation after massive abdominopelvic trauma, or emergent repair of a ruptured abdominal aortic aneurysm (RAAA), are at a significant risk for postoperative abdominal compartment syndrome (ACS). Absorbable prosthetic closure of the abdominal wall has been recommended as a means of managing ACS. However, use of absorbable prosthetic has been associated with very high rates of intestinal fistula formation and ventral hernia formation. The purpose of this study was to retrospectively review our experience with the use of nonabsorbable prosthetic abdominal closures in patients with documented ACS or at high risk for ACS. All patients managed by this technique from July 1995 through July 1997 after repair of ruptured abdominal aortic aneurysm or massive abdominopelvic trauma were evaluated. A total of 18 patients were identified: 15 primary prosthetic placements (Gore-Tex patch, 12; Marlex mesh, 2; and silastic mesh, 1) and 3 delayed prosthetic placements for ACS (Gore-Tex, 1 and Marlex, 2). The mortality rate was 22 percent (4 of 18) and resulted from multisystem organ failure (2 patients), cardiac arrest 1 hour postoperatively (1 patient), and severe closed head injury (1 patient). Secondary closure and prosthetic removal was possible in 16 of 18 patients, including the 2 patients who died of multisystem organ failure within the same hospitalization. Delayed abdominal closure at a subsequent admission was performed in two cases. This same patient developed an enterocutaneous fistula 2 months after discharge. Importantly, only 1 of 18 closed in this manner developed ACS requiring reoperation. The results indicate that use of a nonabsorbable prosthetic, particularly with Gore-Tex, is efficacious in the prevention of postoperative ACS in high-risk patients, while it enhances the possibility for delayed abdominal closure and minimizes the risk of gastrointestinal fistulization associated with other techniques. PMID:10432080

  6. TU-F-17A-04: Respiratory Phase-Resolved 3D MRI with Isotropic High Spatial Resolution: Determination of the Average Breathing Motion Pattern for Abdominal Radiotherapy Planning

    SciTech Connect

    Deng, Z; Pang, J; Yang, W; Yue, Y; Tuli, R; Fraass, B; Li, D; Fan, Z

    2014-06-15

    Purpose: To develop a retrospective 4D-MRI technique (respiratory phase-resolved 3D-MRI) for providing an accurate assessment of tumor motion secondary to respiration. Methods: A 3D projection reconstruction (PR) sequence with self-gating (SG) was developed for 4D-MRI on a 3.0T MRI scanner. The respiration-induced shift of the imaging target was recorded by SG signals acquired in the superior-inferior direction every 15 radial projections (i.e. temporal resolution 98 ms). A total of 73000 radial projections obtained in 8-min were retrospectively sorted into 10 time-domain evenly distributed respiratory phases based on the SG information. Ten 3D image sets were then reconstructed offline. The technique was validated on a motion phantom (gadolinium-doped water-filled box, frequency of 10 and 18 cycles/min) and humans (4 healthy and 2 patients with liver tumors). Imaging protocol included 8-min 4D-MRI followed by 1-min 2D-realtime (498 ms/frame) MRI as a reference. Results: The multiphase 3D image sets with isotropic high spatial resolution (1.56 mm) permits flexible image reformatting and visualization. No intra-phase motion-induced blurring was observed. Comparing to 2D-realtime, 4D-MRI yielded similar motion range (phantom: 10.46 vs. 11.27 mm; healthy subject: 25.20 vs. 17.9 mm; patient: 11.38 vs. 9.30 mm), reasonable displacement difference averaged over the 10 phases (0.74mm; 3.63mm; 1.65mm), and excellent cross-correlation (0.98; 0.96; 0.94) between the two displacement series. Conclusion: Our preliminary study has demonstrated that the 4D-MRI technique can provide high-quality respiratory phase-resolved 3D images that feature: a) isotropic high spatial resolution, b) a fixed scan time of 8 minutes, c) an accurate estimate of average motion pattern, and d) minimal intra-phase motion artifact. This approach has the potential to become a viable alternative solution to assess the impact of breathing on tumor motion and determine appropriate treatment margins

  7. Abdominal Pain, Long-Term

    MedlinePlus

    MENU Return to Web version Abdominal Pain, Long-term See complete list of charts. Ongoing or recurrent abdominal pain, also called chronic pain, may be difficult to diagnose, causing frustration for ...

  8. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) ... final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final recommendation statement applies to adults ages ...

  9. Lymphangiogenesis and Angiogenesis in Abdominal Aortic Aneurysm

    PubMed Central

    Sano, Masaki; Sasaki, Takeshi; Hirakawa, Satoshi; Sakabe, Junichi; Ogawa, Mikako; Baba, Satoshi; Zaima, Nobuhiro; Tanaka, Hiroki; Inuzuka, Kazunori; Yamamoto, Naoto; Setou, Mitsutoshi; Sato, Kohji; Konno, Hiroyuki; Unno, Naoki

    2014-01-01

    The pathogenesis of abdominal aortic aneurysm (AAA) is characterized to be inflammation-associated degeneration of vascular wall. Neovascularization is regularly found in human AAA and considered to play critical roles in the development and rupture of AAA. However, little is known about lymphangiogenesis in AAA. The purpose of this study was to demonstrate both angiogenesis and lymphangiogenesis in AAA. Abdominal aortic tissue was harvested either from autopsy (control group) and during open-repair surgery for AAA (AAA group). Adventitial lymphatic vasa vasorum was observed in both groups, but seemed to be no significant morphological changes in AAA. Immunohistochemical studies identified infiltration of lymphatic vessel endothelial hyaluronan receptor (LYVE) −1, vascular endothelial growth factor (VEGF)-C, and matrix metalloproteinase (MMP)-9-positive macrophages and podoplanin and Prox-1-positive microvessels in the intima/media in AAA wall, where hypoxia-inducible factors (HIF)-1α was expressed. VEGF-C and MMP-9 were not expressed in macrophages infiltrating in the adventitia. Intraoperative indocyanine green fluorescence lymphography revealed lymph stasis in intima/medial in AAA. Fluorescence microscopy of the collected samples also confirmed the accumulation of lymph in the intima/media but not in adventitia. These results demonstrate that infiltration of macrophages in intima/media is associated with lymphangiogenesis and angiogenesis in AAA. Lymph-drainage appeared to be insufficient in the AAA wall. PMID:24651519

  10. Evaluation of a Kalman-based block matching method to assess the bi-dimensional motion of the carotid artery wall in B-mode ultrasound sequences.

    PubMed

    Zahnd, Guillaume; Orkisz, Maciej; Sérusclat, André; Moulin, Philippe; Vray, Didier

    2013-07-01

    We aim at investigating arterial diseases at early stage, by assessing the longitudinal (i.e. in the same direction as the blood flow) motion of the intima-media complex. This recently evidenced phenomenon has been shown to provide relevant and complementary information about vascular health. Our method assesses the longitudinal and radial motion from clinical in vivo B-mode ultrasound sequences. To estimate the trajectory of a selected point during the cardiac cycle, we introduce a block matching method that involves a temporal update of the reference block using a pixel-wise Kalman filter. The filter uses the initial gray-level of the pixel as control signal to avoid divergence due to cumulating errors. The block and search-window sizes are adapted to the tissue of interest. The method was evaluated on image sequences of the common carotid artery, acquired in 57 healthy volunteers and in 25 patients at high cardiovascular risk. Reference trajectories were generated for each sequence by averaging the tracings performed by three observers. Six different computerized techniques were also compared to our method. With a pixel size of 30 μm, the average absolute motion estimation errors were 84 ± 107 μm and 20 ± 19 μm for the longitudinal and radial directions, respectively. This accuracy was of the same order of magnitude as the inter- and intra-observers variability, and smaller than for the other methods. The estimated longitudinal motion amplitude was significantly reduced in at-risk patients compared with healthy volunteers (408 ± 281 μm vs. 643 ± 274 μm, p<0.0001). Our method can constitute a reliable and time-saving technique to investigate the arterial stiffness in clinical studies, in the objective to detect early-stage atherosclerosis. PMID:23612497

  11. Abdominal actinomycosis with multiple myeloma: A case report

    PubMed Central

    ERCOLAK, VEHBI; PAYDAS, SEMRA; ERGIN, MELEK; ATES, BERNA T.; DUMAN, BERNA B.; GUNALDI, MERAL; AFSAR, CIGDEM U.

    2014-01-01

    Actinomycosis is a chronic suppurative infection, for which immune suppression is a predisposing factor. In unusual cases, this disease may present as an abdominal wall involvement simulating a soft tissue tumor as seen in the present case. The presented patient had no signs of trauma or surgical approach and the pathology was considered to be a primary abdominal wall actinomycosis. Preoperative diagnosis is difficult due to the nonspecific nature of clinical presentation, radiographic and laboratory findings. Surgery combined with antibiotic treatment is a curative approach for this relatively rare infection. Surgeons must be aware of this disease in order to ensure correct diagnosis and to prevent performing any unnecessary procedures. The present study describes a case of abdominal actinomycosis with multiple myeloma, together with a review of important points related to this disease. PMID:25202429

  12. Indication of Probe-Axis Angle by Extracting Wall Motion of Heart to Assist in Obtaining Long- and Short-Axis Views on Echocardiography

    NASA Astrophysics Data System (ADS)

    Masuda, K.; Matsuura, H.; Takahashi, R.

    We have developed an algorithm to find standard cross sections of the heart from successive echograms. We first divided an echogram into small spatial regions to detect the typical motion of the mitral valve by analyzing the brightness variation and correlation coefficient among the regions. Furthermore, combining this technique with the optical flow method, we elucidated the region velocity of the left ventricle after centering the valve on echogram. By analyzing symmetry among specified regions, we distinguished the short-axis view of heart from the others.

  13. Steady flow in abdominal aortic aneurysm models.

    PubMed

    Budwig, R; Elger, D; Hooper, H; Slippy, J

    1993-11-01

    Steady flow in abdominal aortic aneurysm models has been examined for four aneurysm sizes over Reynolds numbers from 500 to 2600. The Reynolds number is based on entrance tube diameter, and the inlet condition is fully developed flow. Experimental and numerical methods have been used to determine: (i) the overall features of the flow, (ii) the stresses on the aneurysm walls in laminar flow, and (iii) the onset and characteristics of turbulent flow. The laminar flow field is characterized by a jet of fluid (passing directly through the aneurysm) surrounded by a recirculating vortex. The wall shear stress magnitude in the recirculation zone is about ten times less than in the entrance tube. Both wall shear stress and wall normal stress profiles exhibit large magnitude peaks near the reattachment point at the distal end of the aneurysm. The onset of turbulence in the model is intermittent for 2000 < Re < 2500. The results demonstrate that a slug of turbulence in the entrance tube grows much more rapidly in the aneurysm than in a corresponding length of uniform cross section pipe. When turbulence is present in the aneurysm the recirculation zone breaks down and the wall shear stress returns to a magnitude comparable to that in the entrance tube. PMID:8309237

  14. The dynamics of domain walls and strings

    NASA Technical Reports Server (NTRS)

    Gregory, Ruth; Haws, David; Garfinkle, David

    1989-01-01

    The leading order finite-width corrections to the equation of motion describing the motion of a domain wall are derived. The regime in which this equation of motion is invalid is discussed. Spherically and cylindrically symmetric solutions to this equation of motion are found. A misconception that has arisen in recent years regarding the rigidity (or otherwise) of cosmic strings is also clarified.

  15. Abdominal breathing manoeuvre reduces passive drag acting on gliding swimmers.

    PubMed

    Maruyama, Yusuke; Yanai, Toshimasa

    2015-01-01

    The purpose of this study was to test the hypothesis that the passive drag acting on a gliding swimmer is reduced if the swimmer adopts an abdominal breathing manoeuvre (expanding the abdominal wall) rather than chest breathing manoeuvre (expanding the rib cage). Eleven male participants participated in this study. A specialised towing machine was used to tow each participant with tension set at various magnitudes and to record time series data of towing velocity. Participants were asked to inhale air by expanding the abdominal wall or the rib cage and to maintain the same body configuration throughout gliding. The steady-state velocity was measured and the coefficient of drag was calculated for each towing trial to compare between the breathing manoeuvres. The results showed that the towing velocity was increased by 0.02 m/s with a towing force of 34.3 N and by 0.06 m/s with a towing force of 98.1 N. The coefficient of drag was reduced by 5% with the abdominal breathing manoeuvre, which was found to be statistically significant (p < 0.05). These results indicate that adopting the abdominal breathing manoeuvre during gliding reduces the passive drag and the hypothesis was supported. PMID:26715235

  16. Analysis of abdominal wounds made by surgical trocars using functional luminal imaging probe (FLIP) technology.

    PubMed

    McMahon, Barry P; O'Donovan, Deidre; Liao, Donghua; Zhao, Jingbo; Schiretz, Rich; Heninrich, Russell; Gregersen, Hans

    2008-09-01

    The aim was to use a novel functional luminal imaging probe for evaluation of wound defects and tissue damage resulting from the use of trocars. Following general anesthesia of 4 adult pigs, 6 different trocars were randomly inserted at preselected locations in the porcine abdominal wall. The functional luminal imaging probe was used to profile the trocar holes during bag distension from 8 axial cross-sectional area measurements. The cross-sectional areas and pressure in the bag were recorded and exported to Matlab for analysis and data display. Geometric profiles were generated, and the minimum cross-sectional area and hole length (abdominal wall thickness) were used as endpoints. Successful distensions were made in all cases. The slope of the contours increased away from the narrowest point of the hole. The slope increased more rapidly toward the inner abdominal wall than toward the outer wall. The slope of the linear trend lines for the cross-sectional area-pressure relation represents the compliance at the narrowest point in the wall. The hole length (abdominal wall thickness) could be obtained at different cross-sectional area cutoff points. A cutoff point of 300 mm(2) gave good results when compared to the length of the hole measured after the tissue was excised. This technique represents a new and straightforward way to evaluate the effects of trocars on the abdominal wall. It may also prove useful in comparing techniques and technology from different manufacturers. PMID:18757380

  17. Abdominal imaging: An introduction

    SciTech Connect

    Frick, M.P.; Feinberg, S.B.

    1986-01-01

    This nine-chapter book gives an overview of the integrated approach to abdominal imaging. Chapter 1 provides an introduction to the physics used in medical imaging; chapter 2 is on the selection of imaging modalities. These are followed by four chapters that deal, respectively, with plain radiography, computed tomographic scanning, sonography, and nuclear imaging, as applied to the abdomen. Two chapters then cover contrast material-enhanced studies of the gastrointestinal (GI) tract: one focusing on technical considerations; the other, on radiologic study of disease processes. The final chapter is a brief account of different interventional procedures.

  18. Lower Abdominal Pain.

    PubMed

    Carlberg, David J; Lee, Stephen D; Dubin, Jeffrey S

    2016-05-01

    Although most frequently presenting with lower abdominal pain, appendicitis, colitis, and diverticulitis can cause pain throughout the abdomen and can cause peritoneal and retroperitoneal symptoms. Evaluation and management of lower intestinal disease requires a nuanced approach by the emergency physician, sometimes requiring computed tomography, ultrasonography, MRI, layered imaging, shared decision making, serial examination, and/or close follow-up. Once a presumed or confirmed diagnosis is made, appropriate treatment is initiated, and may include surgery, antibiotics, and/or steroids. Appendicitis patients should be admitted. Diverticulitis and inflammatory bowel disease can frequently be managed on an outpatient basis, but may require admission and surgical consultation. PMID:27133242

  19. Hypnosis for functional abdominal pain.

    PubMed

    Gottsegen, David

    2011-07-01

    Chronic abdominal pain is a common pediatric condition affecting 20% of the pediatric population worldwide. Most children with this disorder are found to have no specific organic etiology and are given the diagnosis of functional abdominal pain. Well-designed clinical trials have found hypnotherapy and guided imagery to be the most efficacious treatments for this condition. Hypnotic techniques used for other somatic symptoms are easily adaptable for use with functional abdominal pain. The author discusses 2 contrasting hypnotic approaches to functional abdominal pain and provides implications for further research. These approaches may provide new insights into this common and complex disorder. PMID:21922712

  20. Combined vesical and abdominal endometriosis following abdominal hysterotomy and tubal ligation.

    PubMed

    Dhall, K; Bhatia, K; Sharma, S K

    1980-09-01

    The article reports on the case of a 29 year old patient who developed abdominal endometriosis 4 years after having had hysterotomy and tubal ligation. About a month after the excision of the endometrial tissue she was examined for suprapubic pains, strangury, and frequency of micturition. A nodule was found in the deepest part of the abdominal wall and the patient was treated for 6 months, without success, with medroxyprogesterone acetate. A subsequent laparotomy showed bladder endometriosis, obviously still an endometrial implant at the time of hysterotomy, which was missed at the time of the first excision. Total hysterectomy was carried out and the patient recovered successfully. Bladder endometriosis is the most common site of involvement among urinary tract endometriosis. The peculiarity of the case presented here is in the total absence of hematuria, and in the fact that pains had no relation with the menstrual cycle. Hormonal therapy is often ineffective, and surgery often the only advisable form of treatment. PMID:12311304