Sample records for abdominal wall motion

  1. Elasticity of the living abdominal wall in laparoscopic surgery.

    PubMed

    Song, Chengli; Alijani, Afshin; Frank, Tim; Hanna, George; Cuschieri, Alfred

    2006-01-01

    Laparoscopic surgery requires inflation of the abdominal cavity and this offers a unique opportunity to measure the mechanical properties of the living abdominal wall. We used a motion analysis system to study the abdominal wall motion of 18 patients undergoing laparoscopic surgery, and found that the mean Young's modulus was 27.7+/-4.5 and 21.0+/-3.7 kPa for male and female, respectively. During inflation, the abdominal wall changed from a cylinder to a dome shape. The average expansion in the abdominal wall surface was 20%, and a working space of 1.27 x 10(-3)m(3) was created by expansion, reshaping of the abdominal wall and diaphragmatic movement. For the first time, the elasticity of human abdominal wall was obtained from the patients undergoing laparoscopic surgery, and a 3D simulation model of human abdominal wall has been developed to analyse the motion pattern in laparoscopic surgery. Based on this study, a mechanical abdominal wall lift and a surgical simulator for safe/ergonomic port placements are under development.

  2. Abdominal wall fat pad biopsy

    MedlinePlus

    Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... most common method of taking an abdominal wall fat pad biopsy . The health care provider cleans the ...

  3. Intra-Abdominal Hypertension and Abdominal Compartment Syndrome after Abdominal Wall Reconstruction: Quaternary Syndromes?

    PubMed

    Kirkpatrick, A W; Nickerson, D; Roberts, D J; Rosen, M J; McBeth, P B; Petro, C C; Berrevoet, Frederik; Sugrue, M; Xiao, Jimmy; Ball, C G

    2017-06-01

    Reconstruction with reconstitution of the container function of the abdominal compartment is increasingly being performed in patients with massive ventral hernia previously deemed inoperable. This situation places patients at great risk of severe intra-abdominal hypertension and abdominal compartment syndrome if organ failure ensues. Intra-abdominal hypertension and especially abdominal compartment syndrome may be devastating systemic complications with systematic and progressive organ failure and death. We thus reviewed the pathophysiology and reported clinical experiences with abnormalities of intra-abdominal pressure in the context of abdominal wall reconstruction. Bibliographic databases (1950-2015), websites, textbooks, and the bibliographies of previously recovered articles for reports or data relating to intra-abdominal pressure, intra-abdominal hypertension, and the abdominal compartment syndrome in relation to ventral, incisional, or abdominal hernia repair or abdominal wall reconstruction. Surgeons should thus consider and carefully measure intra-abdominal pressure and its resultant effects on respiratory parameters and function during abdominal wall reconstruction. The intra-abdominal pressure post-operatively will be a result of the new intra-peritoneal volume and the abdominal wall compliance. Strategies surgeons may utilize to ameliorate intra-abdominal pressure rise after abdominal wall reconstruction including temporizing paralysis of the musculature either temporarily or semi-permanently, pre-operative progressive pneumoperitoneum, permanently removing visceral contents, or surgically releasing the musculature to increase the abdominal container volume. In patients without complicating shock and inflammation, and in whom the abdominal wall anatomy has been so functionally adapted to maximize compliance, intra-abdominal hypertension may be transient and tolerable. Intra-abdominal hypertension/abdominal compartment syndrome in the specific setting of

  4. Don't Forget the Abdominal Wall: Imaging Spectrum of Abdominal Wall Injuries after Nonpenetrating Trauma.

    PubMed

    Matalon, Shanna A; Askari, Reza; Gates, Jonathan D; Patel, Ketan; Sodickson, Aaron D; Khurana, Bharti

    2017-01-01

    Abdominal wall injuries occur in nearly one of 10 patients coming to the emergency department after nonpenetrating trauma. Injuries range from minor, such as abdominal wall contusion, to severe, such as abdominal wall rupture with evisceration of abdominal contents. Examples of specific injuries that can be detected at cross-sectional imaging include abdominal muscle strain, tear, or hematoma, including rectus sheath hematoma (RSH); traumatic abdominal wall hernia (TAWH); and Morel-Lavallée lesion (MLL) (closed degloving injury). These injuries are often overlooked clinically because of (a) a lack of findings at physical examination or (b) distraction by more-severe associated injuries. However, these injuries are important to detect because they are highly associated with potentially grave visceral and vascular injuries, such as aortic injury, and because their detection can lead to the diagnosis of these more clinically important grave traumatic injuries. Failure to make a timely diagnosis can result in delayed complications, such as bowel hernia with potential for obstruction or strangulation, or misdiagnosis of an abdominal wall neoplasm. Groin injuries, such as athletic pubalgia, and inferior costochondral injuries should also be considered in patients with abdominal pain after nonpenetrating trauma, because these conditions may manifest with referred abdominal pain and are often included within the field of view at cross-sectional abdominal imaging. Radiologists must recognize and report acute abdominal wall injuries and their associated intra-abdominal pathologic conditions to allow appropriate and timely treatment. © RSNA, 2017.

  5. Abdominal Wall Endometriosis Mimicking Metastases.

    PubMed

    Nambiar, Rakul; Anoop, T M; Mony, Rari P

    2018-06-01

    Abdominal wall lesions can be broadly divided into nontumorous and tumorous conditions. Nontumorous lesions include congenital lesion, abdominal wall hernia, inflammation and infection, vascular lesions, and miscellaneous conditions like hematoma. Tumorous lesions include benign and malignant neoplasms. Here, we report an unusual case of abdominal wall endometriosis mimicking metastases in a patient with breast carcinoma.

  6. Chronic Abdominal Wall Pain.

    PubMed

    Koop, Herbert; Koprdova, Simona; Schürmann, Christine

    2016-01-29

    Chronic abdominal wall pain is a poorly recognized clinical problem despite being an important element in the differential diagnosis of abdominal pain. This review is based on pertinent articles that were retrieved by a selective search in PubMed and EMBASE employing the terms "abdominal wall pain" and "cutaneous nerve entrapment syndrome," as well as on the authors' clinical experience. In 2% to 3% of patients with chronic abdominal pain, the pain arises from the abdominal wall; in patients with previously diagnosed chronic abdominal pain who have no demonstrable pathological abnormality, this likelihood can rise as high as 30% . There have only been a small number of clinical trials of treatment for this condition. The diagnosis is made on clinical grounds, with the aid of Carnett's test. The characteristic clinical feature is strictly localized pain in the anterior abdominal wall, which is often mischaracterized as a "functional" complaint. In one study, injection of local anesthesia combined with steroids into the painful area was found to relieve pain for 4 weeks in 95% of patients. The injection of lidocaine alone brought about improvement in 83-91% of patients. Long-term pain relief ensued after a single lidocaine injection in 20-30% of patients, after repeated injections in 40-50% , and after combined lidocaine and steroid injections in up to 80% . Pain that persists despite these treatments can be treated with surgery (neurectomy). Chronic abdominal wall pain is easily diagnosed on physical examination and can often be rapidly treated. Any physician treating patients with abdominal pain should be aware of this condition. Further comparative treatment trials will be needed before a validated treatment algorithm can be established.

  7. Chronic abdominal wall pain misdiagnosed as functional abdominal pain.

    PubMed

    van Assen, Tijmen; de Jager-Kievit, Jenneke W A J; Scheltinga, Marc R; Roumen, Rudi M H

    2013-01-01

    The abdominal wall is often neglected as a cause of chronic abdominal pain. The aim of this study was to identify chronic abdominal wall pain syndromes, such as anterior cutaneous nerve entrapment syndrome (ACNES), in a patient population diagnosed with functional abdominal pain, including irritable bowel syndrome, using a validated 18-item questionnaire as an identification tool. In this cross-sectional analysis, 4 Dutch primary care practices employing physicians who were unaware of the existence of ACNES were selected. A total of 535 patients ≥18 years old who were registered with a functional abdominal pain diagnosis were approached when they were symptomatic to complete the questionnaire (maximum 18 points). Responders who scored at least the 10-point cutoff value (sensitivity, 0.94; specificity, 0.92) underwent a diagnostic evaluation to establish their final diagnosis. The main outcome was the presence and prevalence of ACNES in a group of symptomatic patients diagnosed with functional abdominal pain. Of 535 patients, 304 (57%) responded; 167 subjects (31%) recently reporting symptoms completed the questionnaire. Of 23 patients who scored above the 10-point cutoff value, 18 were available for a diagnostic evaluation. In half of these subjects (n = 9) functional abdominal pain (including IBS) was confirmed. However, the other 9 patients were suffering from abdominal wall pain syndrome, 6 of whom were diagnosed with ACNES (3.6% prevalence rate of symptomatic subjects; 95% confidence interval, 1.7-7.6), whereas the remaining 3 harbored a painful lipoma, an abdominal herniation, and a painful scar. A clinically relevant portion of patients previously diagnosed with functional abdominal pain syndrome in a primary care environment suffers from an abdominal wall pain syndrome such as ACNES.

  8. Recovery after abdominal wall reconstruction.

    PubMed

    Jensen, Kristian Kiim

    2017-03-01

    Incisional hernia is a common long-term complication to abdominal surgery, occurring in more than 20% of all patients. Some of these hernias become giant and affect patients in several ways. This patient group often experiences pain, decreased perceived body image, and loss of physical function, which results in a need for surgical repair of the giant hernia, known as abdominal wall reconstruction. In the current thesis, patients with a giant hernia were examined to achieve a better understanding of their physical and psychological function before and after abdominal wall reconstruction. Study I was a systematic review of the existing standardized methods for assessing quality of life after incisional hernia repair. After a systematic search in the electronic databases Embase and PubMed, a total of 26 studies using standardized measures for assessment of quality of life after incisional hernia repair were found. The most commonly used questionnaire was the generic Short-Form 36, which assesses overall health-related quality of life, addressing both physical and mental health. The second-most common questionnaire was the Carolinas Comfort Scale, which is a disease specific questionnaire addressing pain, movement limitation and mesh sensation in relation to a current or previous hernia. In total, eight different questionnaires were used at varying time points in the 26 studies. In conclusion, standardization of timing and method of quality of life assessment after incisional hernia repair was lacking. Study II was a case-control study of the effects of an enhanced recovery after surgery pathway for patients undergoing abdominal wall reconstruction for a giant hernia. Sixteen consecutive patients were included prospectively after the implementation of a new enhanced recovery after surgery pathway at the Digestive Disease Center, Bispebjerg Hospital, and compared to a control group of 16 patients included retrospectively in the period immediately prior to the

  9. Management of complex abdominal wall defects associated with penetrating abdominal trauma.

    PubMed

    Arul, G Suren; Sonka, B J; Lundy, J B; Rickard, R F; Jeffery, S L A

    2015-03-01

    The paradigm of Damage Control Surgery (DCS) has radically improved the management of abdominal trauma, but less well described are the options for managing the abdominal wall itself in an austere environment. This article describes a series of patients with complex abdominal wall problems managed at the UK-led Role 3 Medical Treatment Facility (MTF) in Camp Bastion, Afghanistan. Contemporaneous review of a series of patients with complex abdominal wall injuries who presented to the Role 3 MTF between July and November 2012. Five patients with penetrating abdominal trauma associated with significant damage to the abdominal wall were included. All patients were managed using DCS principles, leaving the abdominal wall open at the end of the first procedure. Subsequent management of the abdominal wall was determined by a multidisciplinary team of general and plastic surgeons, intensivists and specialist nurses. The principles of management identified included minimising tissue loss on initial laparotomy by joining adjacent wounds and marginal debridement of dead tissue; contraction of the abdominal wall was minimised by using topical negative pressure dressing and dermal-holding sutures. Definitive closure was timed to allow oedema to settle and sepsis to be controlled. Closure techniques include delayed primary closure with traction sutures, components separation, and mesh closure with skin grafting. A daily multidisciplinary team discussion was invaluable for optimal decision making regarding the most appropriate means of abdominal closure. Dermal-holding sutures were particularly useful in preventing myostatic contraction of the abdominal wall. A simple flow chart was developed to aid decision making in these patients. This flow chart may prove especially useful in a resource-limited environment in which returning months or years later for closure of a large ventral hernia may not be possible. Published by the BMJ Publishing Group Limited. For permission to use

  10. 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. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Compliance of the abdominal wall during laparoscopic insufflation.

    PubMed

    Becker, Chuck; Plymale, Margaret A; Wennergren, John; Totten, Crystal; Stigall, Kyle; Roth, J Scott

    2017-04-01

    To provide adequate workspace between the viscera and abdominal wall, insufflation with carbon dioxide is a common practice in laparoscopic surgeries. An insufflation pressure of 15 mmHg is considered to be safe in patients, but all insufflation pressures create perioperative and postoperative physiologic effects. As a composition of viscoelastic materials, the abdominal wall should distend in a predictable manner given the pressure of the pneumoperitoneum. The purpose of this study was to elucidate the relationship between degree of abdominal distention and the insufflation pressure, with the goal of determining factors which impact the compliance of the abdominal wall. A prospective, IRB-approved study was conducted to video record the abdomens of patients undergoing insufflation prior to a laparoscopic surgery. Photo samples were taken every 5 s, and the strain of the patient's abdomen in the sagittal plane was determined, as well as the insufflator pressure (stress) at bedside. Patients were insufflated to 15 mmHg. The relationship between the stress and strain was determined in each sample, and compliance of the patient's abdominal wall was calculated. Subcutaneous fat thickness and rectus abdominus muscle thickness were obtained from computed tomography scans. Correlations between abdominal wall compliances and subcutaneous fat and muscle content were determined. Twenty-five patients were evaluated. An increased fat thickness in the abdominal wall had a direct exponential relationship with abdominal wall compliance (R 2  = 0.59, p < 0.05). There was no correlation between muscle and fat thickness. All insufflation pressures create perioperative and postoperative complications. The compliance of patients' abdominal body walls differs, and subcutaneous fat thickness has a direct exponential relationship with abdominal wall compliance. Thus, insufflation pressures can be better tailored per the patient. Future studies are needed to demonstrate the

  12. Free-breathing black-blood CINE fast-spin echo imaging for measuring abdominal aortic wall distensibility: a feasibility study

    NASA Astrophysics Data System (ADS)

    Lin, Jyh-Miin; Patterson, Andrew J.; Chao, Tzu-Cheng; Zhu, Chengcheng; Chang, Hing-Chiu; Mendes, Jason; Chung, Hsiao-Wen; Gillard, Jonathan H.; Graves, Martin J.

    2017-05-01

    The paper reports a free-breathing black-blood CINE fast-spin echo (FSE) technique for measuring abdominal aortic wall motion. The free-breathing CINE FSE includes the following MR techniques: (1) variable-density sampling with fast iterative reconstruction; (2) inner-volume imaging; and (3) a blood-suppression preparation pulse. The proposed technique was evaluated in eight healthy subjects. The inner-volume imaging significantly reduced the intraluminal artifacts of respiratory motion (p  =  0.015). The quantitative measurements were a diameter of 16.3  ±  2.8 mm and wall distensibility of 2.0  ±  0.4 mm (12.5  ±  3.4%) and 0.7  ±  0.3 mm (4.1  ±  1.0%) for the anterior and posterior walls, respectively. The cyclic cross-sectional distensibility was 35  ±  15% greater in the systolic phase than in the diastolic phase. In conclusion, we developed a feasible CINE FSE method to measure the motion of the abdominal aortic wall, which will enable clinical scientists to study the elasticity of the abdominal aorta.

  13. 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

  14. Extraskeletal Ewing sarcoma of the abdominal wall

    PubMed Central

    Farhat, L. Ben; Ghariani, B.; Rabeh, A.; Dali, N.; Said, W.; Hendaoui, L.

    2008-01-01

    Abstract Ewing sarcoma is most commonly a bone tumour which has usually extended into the soft tissues at the time of diagnosis. Exceptionally, this tumour can have an extraskeletal origin. Clinical or imaging findings are non-specific and diagnosis is based on histology. We report a case of an extraskeletal Ewing sarcoma developed in the soft tissues of the abdominal wall in a 35-year-old woman who presented a painful abdominal wall tumefaction. Ultrasongraphy and computed tomography showed a large, well-defined soft tissue mass developed in the left anterolateral muscle group of the abdominal wall. Surgical biopsy was performed and an extraskeletal Ewing sarcoma was identified histologically. PMID:18818133

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nakamura, Katsumasa; Shioyama, Yoshiyuki; Nomoto, Satoru

    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-inspirationmore » 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.« less

  16. Medical evacuation for unrecognized abdominal wall pain: a case series.

    PubMed

    Msonda, Hapu T; Laczek, Jeffrey T

    2015-05-01

    Chronic abdominal pain is a frequently encountered complaint in the primary care setting. The abdominal wall is the etiology of this pain in 10 to 30% of all cases of chronic abdominal pain. Abdominal cutaneous nerve entrapment at the lateral border of the rectus abdominis muscle has been attributed as a cause of this pain. In the military health care system, patients with unexplained abdominal pain are often transferred to military treatment facilities via the Military Medical Evacuation (MEDEVAC) system. We present two cases of patients who transferred via MEDEVAC to our facility for evaluation and treatment of chronic abdominal pain. Both patients had previously undergone extensive laboratory evaluation, imaging, and invasive procedures, such as esophagogastroduodenoscopy before transfer. Upon arrival, history and physical examinations suggested an abdominal wall source to their pain, and both patients experienced alleviation of their abdominal wall pain with lidocaine and corticosteroid injection. This case series highlights the need for military physicians to be aware of abdominal wall pain. Early diagnosis of abdominal cutaneous nerve entrapment syndrome by eliciting Carnett's sign will limit symptom chronicity, avoid unnecessary testing, and even prevent medical evacuation. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  17. Abdominal Wall Endometriosis Eleven Years After Cesarean Section: Case Report

    PubMed

    Djaković, Ivka; Vuković, Ante; Bolanča, Ivan; Soljačić Vraneš, Hrvojka; Kuna, Krunoslav

    2017-03-01

    Endometriosis is a common chronic disease characterized by growth of the endometrial gland and stroma outside the uterus. Symptoms affect physical, mental and social well-being. Extrapelvic location of endometriosis is very rare. Abdominal wall endometriosis occurs in 0.03%-2% of women with a previous cesarean section or other abdominopelvic operation. The leading symptoms are abdominal nodular mass, pain and cyclic symptomatology. The number of cesarean sections is increasing and so is the incidence of abdominal wall endometriosis as a potential complication of the procedure. There are cases of malignant transformation of abdominal wall endometriosis. Therefore, it is important to recognize this condition and treat it surgically. We report a case of a 37-year-old woman with abdominal wall endometriosis 11 years after cesarean section. She had low abdominal pain related to menstrual cycle, which intensified at the end of menstrual bleeding. A nodule painful to palpation was found in the medial part of previous Pfannenstiel incision. Ultrasound guided biopsy was performed and the diagnosis of endometriosis confirmed. Surgery is the treatment of choice for abdominal wall endometriosis. Excision with histologically proven free surgical margins of 1 cm is mandatory to prevent recurrence. A wide spectrum of mimicking conditions is the main reason for late diagnosis and treatment of abdominal wall endometriosis. In our case, the symptoms lasted for eight years and had intensified in the last six months prior to surgery.

  18. [Abdominal wall actinomycosis. A report of a case].

    PubMed

    Rojas Pérez-Ezquerra, Beatriz; Guardia-Dodorico, Lorena; Arribas-Marco, Teresa; Ania-Lahuerta, Aldonza; González Ballano, Isabel; Chipana-Salinas, Margot; Carazo-Hernández, Belén

    2015-01-01

    Abdominal wall Actinomycosis is a rare disease associated with the use of intrauterine device and as a complication of abdominal surgery. Diagnosis is difficult because it is unusual and behaves like a malignant neoplasm. A case report is presented of a patient who had used an intrauterine device for four years and developed a stony tumour in the abdominal wall associated with a set of symptoms that, clinically and radiologically, was simulating a peritoneal carcinomatosis associated with paraneoplastic syndrome, even in the course of an exploratory laparotomy. The patient attended our hospital with a two-month history of abdominal pain and symptoms that mimic a paraneoplastic syndrome. The diagnosis of abdominal actinomycosis was suspected by the finding of the microorganism in cervical cytology together with other cultures and Actinomyces negative in pathological studies, confirming the suspicion of a complete cure with empirical treatment with penicillin. Actinomycosis should be considered in patients with pelvic mass or abdominal wall mass that mimics a malignancy. Antibiotic therapy is the first treatment choice and makes a more invasive surgical management unnecessary. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

  19. Wandering ascaris coming out through the abdominal wall.

    PubMed

    Wani, Mohd L; Rather, Ajaz A; Parray, Fazl Q; Ahangar, Abdul G; Bijli, Akram H; Irshad, Ifat; Nayeem-Ul-Hassan; Khan, Tahir S

    2013-06-01

    A rare case of ascaris coming out through the anterior abdominal wall is reported here. A 40-year-old female had undergone dilatation and curettage by a quack. On the second day she presented with presented with features of peritonitis. She was explored. Resection anastomosis of the ileum was done for multiple perforations of the ileum. Patient developed a fistula in the anterior abdominal wall which was draining bile-colored fluid. On the 12(th) postoperative day a 10-cm-long worm was seen coming out through the fistulous tract which was found to be Ascaris lumbricoids. Ascaris lumbricoids can lead to many complications ranging from worm colic to intestinal obstruction, volvulus, peritonitis, pancreatitis, cholangiohepatitis, liver abscess and many more. Worm has been reported to come out through mouth, nostrils, abdominal drains, T-tubes etc. But ascaris coming out through the anterior abdominal wall is very rare hence reported here.

  20. Technical advances for abdominal wall closure after intestinal and multivisceral transplantation.

    PubMed

    Gerlach, Undine A; Pascher, Andreas

    2012-06-01

    Abdominal wall closure after intestinal transplantation (ITX) or multivisceral transplantation (MVTX) is challenging because of the loss of abdominal domain and wall elasticity as a result of previous operations and donor-to-recipient weight and height mismatch. We report on abdominal wall closure management in 30 ITX and MVTX recipients. In 60% of patients (n = 18), a primary abdominal closure (PAC) was achieved, in 40% (n = 12) a staged closure (SAC) was necessary. Patients with PAC had undergone less pretransplant operations and required less posttransplant relaparotomies. They were mainly ITX recipients or more abdominal domain because of a longer intestinal remnant. A literature review revealed different strategies to overcome a failed primary closure. They focus on graft reduction or an enlargement of the abdominal domain. The latter includes temporary coverage with prosthetic materials for SAC. Definite abdominal closure is achieved by skin only closure, or by using acellular dermal matrix, rotational flaps, rectus muscle fascia or abdominal wall grafts. Abdominal wall reconstruction after ITX/MVTX is commonly demanded and can be conducted by different strategies. The technique should be easy to use in a timely manner and should prevent abdominal infections, intestinal fistulation, incisional hernias, and wound dehiscence.

  1. Desmoid Fibromatosis of the Lower Abdominal Wall in Irrua Nigeria

    PubMed Central

    Awe, Oluwafemi Olasupo; Eluehike, Sylvester

    2018-01-01

    Desmoid fibromatosis (desmoid tumors) is rare tumors. It can occur as intra-abdominal, extraabdominal, or abdominal wall tumor depending on the site. The abdominal wall type is usually sporadic, but few have been associated with familial adenomatous polyposis. They are commonly seen in young females who are pregnant with a history of the previous cesarean section scar or within the 1st year of the last childbirth. There is an association between this tumor, presence of estrogen receptors, and abdominal trauma. We present a 29-year-old Nigerian woman with fungating lower abdominal wall tumor. This tumor is rare, a high index of suspicion will be very important in making the diagnosis. PMID:29643736

  2. [Abdominal traumatic evisceration: reconstruction abdominal wall with biologic mesh and negative pressure therapy].

    PubMed

    Jiménez Gómez, M; Betancor Rivera, N; Lima Sánchez, J; Hernández Hernández, J R

    2016-04-10

    Abdominal traumatic evisceration as a result of high energy trauma is uncommon. Once repaired the possible internal damage, an abdominal wall defect of high complexity may exist, whose reconstruction represents a surgical challenge. Politraumatized male with important abdominal muculocutaneous avulsion and evisceration. After initial repair, the patient developed a big eventration in which we use a porcine dermis-derived mesh (Permacol TM ), a safe and effective alternative in abdominal wall repair, thanks to its seamless integration with other tissues, even when exposed. Negative pressure therapy has been used for the management of wound complications after surgical implantation of PermacolTM mesh. We describe our experience with the use of PermacolTM mesh and negative pressure therapy to aid the wound closure after skin necrosis and exposed mesh.

  3. Wandering Ascaris Coming Out Through the Abdominal Wall

    PubMed Central

    Wani, Mohd L; Rather, Ajaz A.; Parray, Fazl Q.; Ahangar, Abdul G.; Bijli, Akram H.; Irshad, Ifat; Nayeem-Ul-Hassan; Khan, Tahir S.

    2013-01-01

    A rare case of ascaris coming out through the anterior abdominal wall is reported here. A 40-year-old female had undergone dilatation and curettage by a quack. On the second day she presented with presented with features of peritonitis. She was explored. Resection anastomosis of the ileum was done for multiple perforations of the ileum. Patient developed a fistula in the anterior abdominal wall which was draining bile-colored fluid. On the 12th postoperative day a 10-cm-long worm was seen coming out through the fistulous tract which was found to be Ascaris lumbricoids. Ascaris lumbricoids can lead to many complications ranging from worm colic to intestinal obstruction, volvulus, peritonitis, pancreatitis, cholangiohepatitis, liver abscess and many more. Worm has been reported to come out through mouth, nostrils, abdominal drains, T-tubes etc. But ascaris coming out through the anterior abdominal wall is very rare hence reported here. PMID:23930192

  4. Smart textile for respiratory monitoring and thoraco-abdominal motion pattern evaluation.

    PubMed

    Massaroni, Carlo; Venanzi, Cecilia; Silvatti, Amanda P; Lo Presti, Daniela; Saccomandi, Paola; Formica, Domenico; Giurazza, Francesco; Caponero, Michele A; Schena, Emiliano

    2018-05-01

    The use of wearable systems for monitoring vital parameters has gained wide popularity in several medical fields. The focus of the present study is the experimental assessment of a smart textile based on 12 fiber Bragg grating sensors for breathing monitoring and thoraco-abdominal motion pattern analysis. The feasibility of the smart textile for monitoring several temporal respiratory parameters (ie, breath-by-breath respiratory period, breathing frequency, duration of inspiratory and expiratory phases), volume variations of the whole chest wall and of its compartments is performed on 8 healthy male volunteers. Values gathered by the textile are compared to the data obtained by a motion analysis system, used as the reference instrument. Good agreement between the 2 systems on both respiratory period (bias of 0.01 seconds), breathing frequency (bias of -0.02 breaths/min) and tidal volume (bias of 0.09 L) values is demonstrated. Smart textile shows good performance in the monitoring of thoraco-abdominal pattern and its variation, as well. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Chronic abdominal wall pain--a diagnostic challenge for the surgeon.

    PubMed

    Lindsetmo, Rolv-Ole; Stulberg, Jonah

    2009-07-01

    Chronic abdominal wall pain (CAWP) occurs in about 30% of all patients presenting with chronic abdominal pain. The authors review the literature identified in a PubMed search regarding the abdominal wall as the origin of chronic abdominal pain. CAWP is frequently misinterpreted as visceral or functional abdominal pain. Misdiagnosis often leads to a variety of investigational procedures and even abdominal operations with negative results. With a simple clinical test (Carnett's test), >90% of patients with CAWP can be recognized, without risk for missing intra-abdominal pathology. The condition can be confirmed when the injection of local anesthetics in the trigger point(s) relieves the pain. A fasciotomy in the anterior abdominal rectus muscle sheath through the nerve foramina of the affected branch of one of the anterior intercostal nerves heals the pain.

  6. [Desmoid tumor of the abdominal wall].

    PubMed

    Jørgensen, H; Henriksen, L O; Medgyesi, S; Waever, E

    1994-02-07

    Four cases of muscle-aponeurotic fibroadenomatosis (desmoid) of the abdominal wall are reported. The etiological factors, the recurrence rate, the treatment and the pre- and postoperative examinations are discussed.

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

    PubMed

    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.

  8. 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

  9. Abdominal Wall Desmoid during Pregnancy: Diagnostic Challenges

    PubMed Central

    Awwad, Johnny; Hammoud, Nadine; Farra, Chantal; Fares, Farah; Abi Saad, George; Ghazeeri, Ghina

    2013-01-01

    Background. Desmoids are benign tumors, with local invasive features and no metastatic potential, which have rarely been described to be pregnancy associated. Case. We described the rapid growth of an anterior abdominal wall mass in a 40-year-old pregnant woman. Due to its close proximity to the enlarged uterus, it was misdiagnosed to be a uterine leiomyoma by ultrasound examination. Final tissue diagnosis and radical resection were done at the time of abdominal delivery. Conclusion. Due to the diagnostic limitations of imaging techniques, desmoids should always be considered when the following manifestations are observed in combination: progressive growth of a solitary abdominal wall mass during pregnancy and well-delineated smooth tumor margins demonstrated by imaging techniques. This case emphasizes the importance of entertaining uncommon medical conditions in the differential diagnosis of seemingly common clinical manifestations. PMID:23346436

  10. 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

  11. Endometrial stromal cell attachment and matrix homeostasis in abdominal wall endometriomas.

    PubMed

    Itoh, Hiroko; Mogami, Haruta; Bou Nemer, Laurice; Word, Larry; Rogers, David; Miller, Rodney; Word, R Ann

    2018-02-01

    How does progesterone alter matrix remodeling in abdominal wall endometriomas compared with normal endometrium? Progesterone may prevent attachment of endometrial cells to the abdominal wall, but does not ameliorate abnormal stromal cell responses of abdominal wall endometriomas. Menstruation is a tightly orchestrated physiologic event in which steroid hormones and inflammatory cells cooperatively initiate shedding of the endometrium. Abdominal wall endometriomas represent a unique form of endometriosis in which endometrial cells inoculate fascia or dermis at the time of obstetrical or gynecologic surgery. Invasion of endometrium into ectopic sites requires matrix metalloproteinases (MMPs) for tissue remodeling but endometrium is not shed externally. Observational study in 14 cases and 19 controls. Tissues and stromal cells isolated from 14 abdominal wall endometriomas were compared with 19 normal cycling endometrium using immunohistochemistry, quantitative PCR, gelatin zymography and cell attachment assays. P values < 0.05 were considered significant and experiments were repeated in at least three different cell preps to provide scientific rigor to the conclusions. The results indicate that MMP2 and MMP9 are not increased by TGFβ1 in endometrioma stromal cells. Although progesterone prevents attachment of endometrioma cells to matrix components of the abdominal wall, it does not ameliorate these abnormal stromal cell responses to TGFβ1. N/A. Endometriomas were collected from women identified pre-operatively. Not all endometriomas were collected. Stromal cells from normal endometrium were from different patients, not women undergoing endometrioma resection. This work provides insight into the mechanisms by which progesterone may prevent abdominal wall endometriomas but, once established, are refractory to progesterone treatment. Tissue acquisition was supported by NIH P01HD087150. Authors have no competing interests. © The Author(s) 2017. Published by Oxford

  12. Abdominal wall dysfunction in adult bladder exstrophy: a treatable but under-recognized problem.

    PubMed

    Manahan, M A; Campbell, K A; Tufaro, A P

    2016-08-01

    Bladder exstrophy is defined by urogenital and skeletal abnormalities with cosmetic and functional deformity of the lower anterior abdominal wall. The primary management objectives have historically been establishment of urinary continence with renal function preservation, reconstruction of functional and cosmetically acceptable external genitalia, and abdominal wall closure of some variety. The literature has focused on the challenges of neonatal approaches to abdominal wall closure; however, there has been a paucity of long-term followup to identify the presence and severity of abdominal wall defects in adulthood. Our goal was to characterize the adult disease and determine effective therapy. A retrospective review of a consecutive series of six patients was performed. We report and characterize the presence of severe abdominal wall dysfunction in these adult exstrophy patients treated as children. We tailored an abdominal wall and pelvic floor reconstruction with long-term success to highlight a need for awareness of the magnitude of the problem and its solvability. The natural history of abdominal wall laxity and the long-term consequences of cloacal exstrophy closure have gone unexplored and unreported. Evaluation of our series facilitates understanding in this complex area and may be valuable for patients who are living limited lives thinking that no solution is available.

  13. Laparoscopic excision of an epidermoid cyst arising from the deep abdominal wall.

    PubMed

    Ishikawa, Hajime; Nakai, Takuya; Ueda, Kazuki; Haji, Seiji; Takeyama, Yoshifumi; Ohyanagi, Harumasa

    2009-10-01

    Epidermoid cysts are the most common type of cutaneous cyst. However, their occurrence in the deep abdominal wall has not yet been reported. Here, we present the case of a 60-year-old woman who developed an epidermoid cyst in the deep abdominal wall, which was resected laparoscopically. The patient presented with right upper quadrant abdominal pain on admission to our hospital. Computed tomography revealed cholecystolithiasis and an incidentally identified well-defined hypoattenuating mass (62 x 47 x 65 mm) in the deep abdominal wall on the left side of the navel. We performed laparoscopic complete resection of the abdominal wall tumor followed by cholecystectomy. The excised specimen was a cyst covered with a smooth thin membrane and contained sludge. Histopathologic examination revealed an epidermoid cyst. This is a very rare case with no previous reports on a similar type of epidermoid cyst.

  14. Genetics Home Reference: abdominal wall defect

    MedlinePlus

    ... are two main types of abdominal wall defects: omphalocele and gastroschisis . Omphalocele is an opening in the center of the ... covering the exposed organs in gastroschisis. Fetuses with omphalocele may grow slowly before birth (intrauterine growth retardation) ...

  15. 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

  16. Chronic abdominal wall pain and ultrasound-guided abdominal cutaneous nerve infiltration: a case series.

    PubMed

    Kanakarajan, Saravanakumar; High, Kristina; Nagaraja, Ravi

    2011-03-01

    Chronic abdominal wall pain occurs in about 10-30% of patients presenting with chronic abdominal pain. Entrapment of abdominal cutaneous nerves at the lateral border of the rectus abdominis muscle has been attributed as a cause of abdominal wall pain. We report our experience of treating such patients using ultrasound-guided abdominal cutaneous nerve infiltration. We conducted a retrospective audit of abdominal cutaneous nerve infiltration performed in the period between September 2008 to August 2009 in our center. All patients had received local anesthetic and steroid injection under ultrasound guidance. The response to the infiltration was evaluated in the post-procedure telephone review as well as in the follow-up clinic. Brief pain inventory (BPI) and numerical rating scale pain scores were collated from two points: the initial outpatient clinic and the follow up clinic up to 5 months following the injection. Nine patients had abdominal cutaneous nerve injections under ultrasound guidance in the period under review. Six patients reported 50% pain relief or more (responders) while three patients did not. Pain and BPI scores showed a decreasing trend in responders. The median duration of follow-up was 12 weeks. Ultrasound can reliably be used for infiltration of the abdominal cutaneous nerves. This will improve the safety as well as diagnostic utility of the procedure. Wiley Periodicals, Inc.

  17. Temporary closure of the abdominal wall by use of silicone rubber sheets after operative repair of ruptured abdominal aortic aneurysms.

    PubMed

    Akers, D L; Fowl, R J; Kempczinski, R F; Davis, K; Hurst, J M; Uhl, S

    1991-07-01

    Management of patients after operative repair of abdominal aortic aneurysms can be further complicated if primary closure of the abdominal wall cannot be technically accomplished or is associated with profound increases in intraabdominal and peak inspiratory pressures. We recently treated five patients with ruptured abdominal aortic aneurysms and one patient with a ruptured thoracoabdominal aneurysm whose abdominal incisions had to be closed with a Dacron reinforced, silicone sheet. All patients were hemodynamically unstable either at admission to the hospital or became so during operation. Four patients required the insertion of a silicone rubber sheet at the primary operation because of massive retroperitoneal hematoma or edema of the bowel wall or both. Incisions in two patients were closed primarily, but the patients required reexploration and secondary closure with silicone rubber sheets because of the development of marked increases in peak inspiratory pressures, intraabdominal pressures, and decreased urinary output. Four of the six patients subsequently underwent successful removal of the silicone rubber sheets with delayed primary closure of the abdominal wall, and two others died before removal. The patient with the ruptured thoracoabdominal aneurysm died on postoperative day 20 because of pulmonary sepsis but had a healed abdominal incision. The three surviving patients have been discharged. A silicone rubber sheet may be necessary for closure of the abdominal wall after repair of ruptured abdominal aortic aneurysm in patients where primary abdominal wall closure is impossible or where it results in compromise in respiratory or renal function.

  18. [The cutaneous groin flap for coverage of a full-thickness abdominal wall defect].

    PubMed

    Doebler, O; Spierer, R

    2010-08-01

    A full-thickness defect of the abdominal wall is rare and may occur as a complication of extended abdominal surgery procedures. We report about a 69-year-old patient who was presented to our department with a full-thickness abdominal wall defect and a fully exposed collagen-mesh for reconstructive wound closure. 13 operations with resections of necrotic parts of the abdominal wall were performed following a complicated intraabdominal infection. After debridement and mesh explantation, closure of the remaining defect of the lower abdominal region was achieved by a cutaneous groin flap. Georg Thieme Verlag KG Stuttgart New York.

  19. 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.

  20. [Gas gangrene of the abdominal wall due to underlying GI pathology: seven cases].

    PubMed

    Monneuse, O; Gruner, L; Barth, X; Malick, P; Timsit, M; Gignoux, B; Tissot, E

    2007-01-01

    Gas gangrene of the abdominal wall is a rare clinical occurrence with high rates of morbidity and mortality. The primary source of the infection is often unknown. To analyze the primary underlying intestinal etiologies and diagnostic approaches of gas gangrene of the abdominal wall, and to highlight specific treatment problems, particularly that of constructing a colostomy exteriorized through a massively infected abdominal wall. Seven cases of abdominal wall gas gangrene due to a gastrointestinal etiology were identified. (Cases arising from proctologic sources or related to recent abdominal surgery were excluded.) During the same period, 39 other patients presenting with abdominal wall gangrene from non-intestinal sources were treated. The etiologies were: perforated sigmoid diverticulitis (n=2), perforated appendicitis (n=1), acute pancreatitis with associated cecal perforation (n=1), and perforated colorectal cancer (n=3). Four of the seven patients died despite treatment (mortality of 57%). The clinical presentations of these seven cases demonstrate that a GI source must be suspected whenever a patient presents with abdominal wall gas gangrene, even when there are no specific GI symptoms. Imaging, particularly with CT scan, is essential both to visualize the extent of tissue necrosis and to reveal underlying primary GI pathology. This optimizes the surgical approach both by allowing for complete debridement and drainage of infected tissue, and by focussing the intervention on correction of the underlying primary GI source of infection.

  1. Fetal anterior abdominal wall defects: prenatal imaging by magnetic resonance imaging.

    PubMed

    Victoria, Teresa; Andronikou, Savvas; Bowen, Diana; Laje, Pablo; Weiss, Dana A; Johnson, Ann M; Peranteau, William H; Canning, Douglas A; Adzick, N Scott

    2018-04-01

    Abdominal wall defects range from the mild umbilical cord hernia to the highly complex limb-body wall syndrome. The most common defects are gastroschisis and omphalocele, and the rarer ones include the exstrophy complex, pentalogy of Cantrell and limb-body wall syndrome. Although all have a common feature of viscera herniation through a defect in the anterior body wall, their imaging features and, more important, postnatal management, differ widely. Correct diagnosis of each entity is imperative in order to achieve appropriate and accurate prenatal counseling and postnatal management. In this paper, we discuss fetal abdominal wall defects and present diagnostic pearls to aid with diagnosis.

  2. [Abdominal wall reconstruction with collagen membrane in an animal model of abdominal hernia. A preliminary report].

    PubMed

    Łukasiewicz, Aleksander; Drewa, Tomasz; Skopińska-Wiśniewska, Joanna; Molski, Stanisław

    2008-01-01

    Abdominal hernia repair is one of the most common surgical procedures. Current data indicate that the best treatment results are achieved with use of synthetic material to reinforce weakened abdominal wall. Prosthetic materials utilized for hernia repair induce adhesions with underlying viscera. They should be therefore separated from them by a layer of peritoneum otherwise adhesions may cause to serious complications such as bowel-skin fistulas. The aim of our work was to determine if implantation of our collagen membrane into abdominal wall defect induce adhesions in rat model of ventral hernia. The collagen film was obtained by acetic acid extraction of rat tail tendons and than casting the soluble fraction onto polyethylene shits. Abdominal wall defect was created in 10 Wistar male rats. Collagen membranes were implanted into the defect using interrupted polypropylene stitches. After 3 months of observation all animals were sacrificed. No adhesions between path structure and bowel developed. In one often rats (10%) adhesion between fixating stitch and omentum was observed. Complete mesothelium lining and vascular ingrowth were microscopically observed within implanted structure. Promising result requires further confirmation in a larger series of animals.

  3. Study of Individual Characteristic Abdominal Wall Thickness Based on Magnetic Anchored Surgical Instruments

    PubMed Central

    Dong, Ding-Hui; Liu, Wen-Yan; Feng, Hai-Bo; Fu, Yi-Li; Huang, Shi; Xiang, Jun-Xi; Lyu, Yi

    2015-01-01

    Background: Magnetic anchored surgical instruments (MASI), relying on magnetic force, can break through the limitations of the single port approach in dexterity. Individual characteristic abdominal wall thickness (ICAWT) deeply influences magnetic force that determines the safety of MASI. The purpose of this study was to research the abdominal wall characteristics in MASI applied environment to find ICAWT, and then construct an artful method to predict ICAWT, resulting in better safety and feasibility for MASI. Methods: For MASI, ICAWT is referred to the thickness of thickest point in the applied environment. We determined ICAWT through finding the thickest point in computed tomography scans. We also investigated the traits of abdominal wall thickness to discover the factor that can be used to predict ICAWT. Results: Abdominal wall at C point in the middle third lumbar vertebra plane (L3) is the thickest during chosen points. Fat layer thickness plays a more important role in abdominal wall thickness than muscle layer thickness. “BMI-ICAWT” curve was obtained based on abdominal wall thickness of C point in L3 plane, and the expression was as follow: f(x) = P1 × x2 + P2 × x + P3, where P1 = 0.03916 (0.01776, 0.06056), P2 = 1.098 (0.03197, 2.164), P3 = −18.52 (−31.64, −5.412), R-square: 0.99. Conclusions: Abdominal wall thickness of C point at L3 could be regarded as ICAWT. BMI could be a reliable predictor of ICAWT. In the light of “BMI-ICAWT” curve, we may conveniently predict ICAWT by BMI, resulting a better safety and feasibility for MASI. PMID:26228215

  4. 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.

  5. Risk Assessment of Abdominal Wall Thickness Measured on Pre-Operative Computerized Tomography for Incisional Surgical Site Infection after Abdominal Surgery.

    PubMed

    Tongyoo, Assanee; Chatthamrak, Putipan; Sriussadaporn, Ekkapak; Limpavitayaporn, Palin; Mingmalairak, Chatchai

    2015-07-01

    The surgical site infection (SSI) is a common complication of abdominal operation. It relates to increased hospital stay, increased healthcare cost, and decreased patient's quality of life. Obesity, usually defined by BMI, is known as one of the risks of SSI. However, the thickness of subcutaneous layers of abdominal wall might be an important local factor affecting the rate of SSI after the abdominal operations. The objective of this study is to assess the importance of the abdominal wall thickness on incisional SSI rate. The subjects of the present study were patients who had undergone major abdominal operations at Thammasat University Hospital between June 2013 and May 2014, and had been investigated with CT scans before their operations. The demographic data and clinical information of these patients were recorded. The thickness ofsubcutaneous fatty tissue from skin down to the most superficial layer of abdominal wall muscle at the surgical site was measured on CT images. The wound infectious complication was reviewed and categorized as superficial and deep incisional SSIfollowing the definition from Centersfor Disease Control and Prevention (CDC) guidelines. The significance ofeach potentialfactors on SSI rates was determined separately with student t-test for quantitative data and χ2-test for categorical data. Then all factors, which had p < 0.10, were included into the multivariate logistic regression analysis and were analyzed with significance at p < 0.05. One hundred and thirty-nine patients were included in this study. They all underwent major abdominal surgery and had had pre-operative CTscans. Post-operative SSI was 25.2% (35/139), superficial and deep types in 27 and 8 patients, respectively. The comparison of abdominal wall thickness between patients with and without infection was significantly different (20.0 ± 8.4 mm and 16.0 ± 7.2 mm, respectively). When the thickness at 20 mm was used as the cut-off value, 43 of 139 patients had abdominal wall

  6. Abdominal wall sinus due to impacting gallstone during laparoscopic cholecystectomy: an unusual complication.

    PubMed

    Pavlidis, T E; Papaziogas, B T; Koutelidakis, I M; Papaziogas, T B

    2002-02-01

    During laparoscopic cholecystectomy, perforation of the gallbladder can occurs in < or = 20% of cases, while gallstone spillage occurs in < or = 6% of cases. In most cases, there are no consequences. Gallstones can be lost in the abdominal wall as well as the abdomen during extraction of the gallbladder. The fate of such lost gallstones, which can lead to the formation of an abscess, an abdominal wall mass, or a persistent sinus, has not been studied adequately. Herein we report the case of a persistent sinus of the abdominal wall after an emergent laparoscopic cholecystectomy in an 82-year-old woman with gangrenous cholecystitis and perforation of the friable wall in association with an empyema of the gallbladder. The culture of the obtained pus was positive for Escherichia coli. After a small leak of dirty fluid from the wound of the epigastric port site of 4 months' duration, surgical exploration under local anesthesia revealed that the sinus was caused by spilled gallstones impacting into the abdominal wall between the posterior sheath and left rectus abdominalis muscle. The removal of the stones resulted in complete healing. Long-term complications after laparoscopic cholecystectomy involving the abdominal wall are rare but important possible consequences that could be avoided.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, Zhoubing; Allen, Wade M.; Baucom, Rebeccah B.

    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,more » 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

  8. Reconstruction of infected abdominal wall defects using latissimus dorsi free flap.

    PubMed

    Kim, Sang Wha; Han, Sang Chul; Hwang, Kyu Tae; Ahn, Byung Kyu; Kim, Jeong Tae; Kim, Youn Hwan

    2013-12-01

    Infected abdominal defects are a challenge to surgeons. In this study, we describe 10 cases in which the latissimus dorsi myocutaneous flap was used for successful reconstruction of abdominal wall defects severely infected with methicillin-resistant Staphylococcus aureus (MRSA). Retrospective review of 10 patients with abdominal wall defects that were reconstructed using the latissimus dorsi myocutaneous flap between 2002 and 2010. All patients had abdominal defects with hernias, combined with MRSA infections. The sizes of the flaps ranged from 120 to 364 cm(2) . The deep inferior epigastric artery was the recipient vessel in nine patients and the internal mammary vessels were used for one patient. There were no complications relating to the flaps, although there were other minor complications including wound dehiscence, haematoma and fluid correction. After reconstruction, there were no signs of infection during follow-up periods, and the patients were satisfied with the final results. Reconstruction using the latissimus dorsi myocutaneous flap, including muscle fascia structures, is a potential treatment option for severely infected large abdominal wall defects. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.

  9. Design and characterisation of a wall motion phantom.

    PubMed

    Dineley, J; Meagher, S; Poepping, T L; McDicken, W N; Hoskins, P R

    2006-09-01

    Arterial wall motion is an essential feature of a healthy cardiovascular system and it is known that wall motion is affected by age and disease. In recent years, methods have been developed for measurement of wall motion with the intention of providing diagnostically useful information. An issue with all of these techniques is the accuracy and variability of both wall motion and derived quantities such as elasticity, which requires the development of suitable test tools. In this paper, a vessel wall phantom is described for use in ultrasound studies of wall motion. The vessel was made from polyvinyl alcohol (PVA) subjected to a freeze-thaw process to form a cryogel (PVA-C). The elastic modulus, acoustic velocity and attenuation coefficient varied from 57 kPa, 1543 m s(-1) and 0.18 dB cm(-1) MHz(-1) for one freeze-thaw cycle to 330 kPa, 1583 m s(-1) and 0.42 dB cm(-1) MHz(-1) for 10 freeze-thaw cycles. Wall motion was effected by the use of pulsatile flow produced from a gear pump. The use of a downstream flow resistor removed gross distortions in the wall motion waveform, possibly by removal of reflected pressure waves. However, a low amplitude 20 Hz oscillation remained, which is unphysiologic and thought to be caused by the vibration of the distended PVA-C vessel.

  10. Intestinal injury mechanisms after blunt abdominal impact.

    PubMed

    Cripps, N P; Cooper, G J

    1997-03-01

    Intestinal injury is frequent after non-penetrating abdominal trauma, particularly after modern, high-energy transfer impacts. Under these circumstances, delay in the diagnosis of perforation is a major contributor to morbidity and mortality. This study establishes patterns of intestinal injury after blunt trauma by non-penetrating projectiles and examines relationships between injury distribution and abdominal wall motion. Projectile impacts of variable momentum were produced in 31 anaesthetised pigs to cause abdominal wall motion of varying magnitude and velocity. No small bowel injury was observed at initial impact velocity of less than 40 m/s despite gross abdominal compression. At higher velocity, injury to the small bowel was frequent, irrespective of the degree of abdominal compression (P = 0.00044). Large bowel injury was observed at all impact velocities and at all degrees of abdominal compression. This study confirms the potential for intestinal injury in high velocity, low momentum impacts which do not greatly compress the abdominal cavity and demonstrates apparent differences in injury mechanisms for the small bowel and colon. Familiarity with injury mechanisms may reduce delays in the diagnosis of intestinal perforation in both military and civilian situations.

  11. Regional cardiac wall motion from gated myocardial perfusion SPECT studies

    NASA Astrophysics Data System (ADS)

    Smith, M. F.; Brigger, P.; Ferrand, S. K.; Dilsizian, V.; Bacharach, S. L.

    1999-06-01

    A method for estimating regional epicardial and endocardial wall motion from gated myocardial perfusion SPECT studies has been developed. The method uses epicardial and endocardial boundaries determined from four long-axis slices at each gate of the cardiac cycle. The epicardial and endocardial wall position at each time gate is computed with respect to stationary reference ellipsoids, and wall motion is measured along lines normal to these ellipsoids. An initial quantitative evaluation of the method was made using the beating heart from the dynamic mathematical cardiac torso (MCAT) phantom, with and without a 1.5-cm FWHM Gaussian blurring filter. Epicardial wall motion was generally well-estimated within a fraction of a 3.56-mm voxel, although apical motion was overestimated with the Gaussian filter. Endocardial wall motion was underestimated by about two voxels with and without the Gaussian filter. The MCAT heart phantom was modified to model hypokinetic and dyskinetic wall motion. The wall motion analysis method enabled this abnormal motion to be differentiated from normal motion. Regional cardiac wall motion also was analyzed for /sup 201/Tl patient studies. Estimated wall motion was consistent with a nuclear medicine physician's visual assessment of motion from gated long-axis slices for male and female study examples. Additional research is required for a comprehensive evaluation of the applicability of the method to patient studies with normal and abnormal wall motion.

  12. 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

  13. Ectodermal Wnt signaling regulates abdominal myogenesis during ventral body wall development.

    PubMed

    Zhang, Lingling; Li, Hanjun; Yu, Jian; Cao, Jingjing; Chen, Huihui; Zhao, Haixia; Zhao, Jianzhi; Yao, Yiyun; Cheng, Huihui; Wang, Lifang; Zhou, Rujiang; Yao, Zhengju; Guo, Xizhi

    2014-03-01

    Defects of the ventral body wall are prevalent birth anomalies marked by deficiencies in body wall closure, hypoplasia of the abdominal musculature and multiple malformations across a gamut of organs. However, the mechanisms underlying ventral body wall defects remain elusive. Here, we investigated the role of Wnt signaling in ventral body wall development by inactivating Wls or β-catenin in murine abdominal ectoderm. The loss of Wls in the ventral epithelium, which blocks the secretion of Wnt proteins, resulted in dysgenesis of ventral musculature and genito-urinary tract during embryonic development. Molecular analyses revealed that the dermis and myogenic differentiation in the underlying mesenchymal progenitor cells was perturbed by the loss of ectodermal Wls. The activity of the Wnt-Pitx2 axis was impaired in the ventral mesenchyme of the mutant body wall, which partially accounted for the defects in ventral musculature formation. In contrast, epithelial depletion of β-catenin or Wnt5a did not resemble the body wall defects in the ectodermal Wls mutant. These findings indicate that ectodermal Wnt signaling instructs the underlying mesodermal specification and abdominal musculature formation during ventral body wall development, adding evidence to the theory that ectoderm-mesenchyme signaling is a potential unifying mechanism for the origin of ventral body wall defects. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Desmoid tumors of the abdominal wall: A case report

    PubMed Central

    Overhaus, Marcus; Decker, Pan; Fischer, Hans Peter; Textor, Hans Jochen; Hirner, Andreas

    2003-01-01

    Background Desmoid tumors are slow growing deep fibromatoses with aggressive infiltration of adjacent tissue but without any metastatic potential. Case Presentation We report on two female patients with desmoid tumor of the abdominal wall who underwent primary resection. Both patients had a history of an earlier abdominal surgery. Preoperative evaluation included abdominal ultrasound, magnetic resonance imaging and computed tomography. The histology in both cases revealed a desmoid tumor. Conclusion Complete surgical resection is the first line management of this tumor entity. PMID:12890284

  15. Rare Abdominal Wall Malformation: Case Report of Umbilical Cord Hernia.

    PubMed

    Gliha, Andro; Car, Andrija; Višnjić, Stjepan; Zupancic, Bozidar; Kondza, Karmen; Petracic, Ivan

    The umbilical cord hernia is the rarest form of abdominal wall malformations, anatomically completely different from gastroschisis and omphalocele. It occurs due to the permanent physiological evisceration of abdominal organs into umbilical celom and persistence of a patent umbilical ring. The umbilical cord hernia is often mistaken for omphalocele and called "small omphalocele". Here we present a case of a female newborn with umbilical cord hernia treated in our Hospital. After preoperative examinations surgery was done on the second day of life. The abdominal wall was closed without tension. The aim of this article is to present the importance of the proper diagnose of these three entities and to stimulate academic community for the answer, is this umbilical cord hernia or small omphalocele.

  16. Effects of non-invasive ventilation and posture on chest wall volumes and motion in patients with amyotrophic lateral sclerosis: a case series

    PubMed Central

    Magalhães, Cristiana M.; Fregonezi, Guilherme A.; Vidigal-Lopes, Mauro; Vieira, Bruna S. P. P.; Vieira, Danielle S. R.; Parreira, Verônica F.

    2016-01-01

    ABSTRACT Background The effects of non-invasive ventilation (NIV) on the breathing pattern and thoracoabdominal motion of patients with amyotrophic lateral sclerosis (ALS) are unknown. Objectives 1) To analyze the influence of NIV on chest wall volumes and motion assessed by optoelectronic plethysmography in ALS patients and 2) to compare these parameters in the supine and sitting positions to those of healthy individuals (without NIV). Method Nine ALS patients were evaluated in the supine position using NIV. In addition, the ALS patients and nine healthy individuals were evaluated in both sitting and supine positions. Statistical analysis was performed using the paired Student t-test or Wilcoxon test and the Student t-test for independent samples or Mann-Whitney U test. Results Chest wall volume increased significantly with NIV, mean volume=0.43 (SD=0.16)L versus 0.57 (SD=0.19)L (p=0.04). No significant changes were observed for the pulmonary rib cage, abdominal rib cage, or abdominal contribution. The index of the shortening velocity of the diaphragmatic muscle, mean=0.15 (SD=0.05)L/s versus 0.21 (SD=0.05)L/s (p<0.01), and abdominal muscles, mean=0.09 (SD=0.02)L/s versus 0.14 (SD=0.06)L/s (p<0.01), increased during NIV. Comparisons between the supine and sitting positions showed similar changes in chest wall motion in both groups. However, the ALS patients presented a significantly lower contribution of the abdomen in the supine position compared with the controls, mean=56 (SD=13) versus 69 (SD=10) (p=0.02). Conclusions NIV improved chest wall volumes without changing the contribution of the chest wall compartment in ALS patients. In the supine position, ALS patients had a lower contribution of the abdomen, which may indicate early diaphragmatic dysfunction. PMID:27556390

  17. Effects of non-invasive ventilation and posture on chest wall volumes and motion in patients with amyotrophic lateral sclerosis: a case series.

    PubMed

    Magalhães, Cristiana M; Fregonezi, Guilherme A; Vidigal-Lopes, Mauro; Vieira, Bruna S P P; Vieira, Danielle S R; Parreira, Verônica F

    2016-01-01

    The effects of non-invasive ventilation (NIV) on the breathing pattern and thoracoabdominal motion of patients with amyotrophic lateral sclerosis (ALS) are unknown. 1) To analyze the influence of NIV on chest wall volumes and motion assessed by optoelectronic plethysmography in ALS patients and 2) to compare these parameters in the supine and sitting positions to those of healthy individuals (without NIV). Nine ALS patients were evaluated in the supine position using NIV. In addition, the ALS patients and nine healthy individuals were evaluated in both sitting and supine positions. Statistical analysis was performed using the paired Student t-test or Wilcoxon test and the Student t-test for independent samples or Mann-Whitney U test. Chest wall volume increased significantly with NIV, mean volume=0.43 (SD=0.16)L versus 0.57 (SD=0.19)L (p=0.04). No significant changes were observed for the pulmonary rib cage, abdominal rib cage, or abdominal contribution. The index of the shortening velocity of the diaphragmatic muscle, mean=0.15 (SD=0.05)L/s versus 0.21 (SD=0.05)L/s (p<0.01), and abdominal muscles, mean=0.09 (SD=0.02)L/s versus 0.14 (SD=0.06)L/s (p<0.01), increased during NIV. Comparisons between the supine and sitting positions showed similar changes in chest wall motion in both groups. However, the ALS patients presented a significantly lower contribution of the abdomen in the supine position compared with the controls, mean=56 (SD=13) versus 69 (SD=10) (p=0.02). NIV improved chest wall volumes without changing the contribution of the chest wall compartment in ALS patients. In the supine position, ALS patients had a lower contribution of the abdomen, which may indicate early diaphragmatic dysfunction.

  18. An evaluation of abdominal wall closure in general surgical and gynecological residents.

    PubMed

    Williams, Z; Williams, S; Easley, H A; Seita, H M; Hope, W W

    2017-12-01

    To evaluate abdominal wall closure knowledge base and technical skills in surgical and OB/GYN residents. Residents consented to participate in a skills laboratory and quiz. The skills portion involved closure of a 10-cm incision on a simulated abdominal wall. Participants were timed, filmed, and graded using a standardized grading system. Thirty surgical and OB/GYN residents participated. All residents reported closing the abdominal wall continuously, 97% preferred slowly absorbing sutures (28/29), 97% preferred taking 1-cm bites (29/30), and 93% spaced bites 1 cm apart (27/29). However, 77% (10/13) of surgery residents identified 4:1 as the ideal suture to wound length ratio; 47% (7/15) of OB/GYN residents believed it to be 2:1, and another 40% (6/15) indicated 3:1 (p < 0.0001). In the simulation, OB/GYN residents used significantly fewer stitches (p = 0.0028), significantly more distance between bites (p < 0.0001), and significantly larger bite size (p < 0.0001) than surgery residents. When graded, there was no significant difference between programs. Despite some knowledge regarding the principles of abdominal wall closure among surgical and OB/GYN residents, more instruction is needed. We identified some differences in knowledge base and techniques for abdominal wall closure among general surgery and OB/GYN residents, which are likely due to differences in educational curriculums.

  19. Clustering Of Left Ventricular Wall Motion Patterns

    NASA Astrophysics Data System (ADS)

    Bjelogrlic, Z.; Jakopin, J.; Gyergyek, L.

    1982-11-01

    A method for detection of wall regions with similar motion was presented. A model based on local direction information was used to measure the left ventricular wall motion from cineangiographic sequence. Three time functions were used to define segmental motion patterns: distance of a ventricular contour segment from the mean contour, the velocity of a segment and its acceleration. Motion patterns were clustered by the UPGMA algorithm and by an algorithm based on K-nearest neighboor classification rule.

  20. Inspiratory flow rate, not type of incentive spirometry device, influences chest wall motion in healthy individuals.

    PubMed

    Chang, Angela T; Palmer, Kerry R; McNaught, Jessie; Thomas, Peter J

    2010-08-01

    This study investigated the effect of flow rates and spirometer type on chest wall motion in healthy individuals. Twenty-one healthy volunteers completed breathing trials to either two times tidal volume (2xV(T)) or inspiratory capacity (IC) at high, low, or natural flow rates, using a volume- or flow-oriented spirometer. The proportions of rib cage movement to tidal volume (%RC/V(T)), chest wall diameters, and perceived level of exertion (RPE) were compared. Low and natural flow rates resulted in significantly lower %RC/V(T) compared to high flow rate trials (p=0.001) at 2xV(T). Low flow trials also resulted in significantly less chest wall motion in the upper anteroposterior direction than high and natural flow rates (p<0.001). At IC, significantly greater movement occurred in the abdominal lateral direction during low flow compared to high and natural flow trials (both p<0.003). RPE was lower for the low flow trials compared to high flow trials at IC and 2xV(T) (p<0.01). In healthy individuals, inspiratory flow (not device type) during incentive spirometry determines the resultant breathing pattern. High flow rates result in greater chest wall motion than low flow rates.

  1. Takedown of enterocutaneous fistula and complex abdominal wall reconstruction.

    PubMed

    Slade, Dominic Alexander James; Carlson, Gordon Lawrence

    2013-10-01

    Key steps in managing patients with enterocutaneous fistulation and an abdominal wall defect include dealing effectively with abdominal sepsis and providing safe and effective nutritional support and skin care, then assessing intestinal and abdominal anatomy, before undertaking reconstructive surgery. The complexity, cost, and morbidity associated with such cases justifies creation of specialized centers in which gastroenterologic, hernia, and plastic surgical expertise, as well as experienced wound and stoma nursing and nutritional and psychological support, can be made available for patients with these challenging problems. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Mesh abdominal wall hernia surgery is safe and effective-the harm New Zealand media has done.

    PubMed

    Kelly, Steven

    2017-10-06

    Patients in New Zealand have now developed a fear of mesh abdominal wall hernia repair due to inaccurate media reporting. This article outlines the extensive literature that confirms abdominal wall mesh hernia repair is safe and effective. The worsening confidence in the transvaginal mesh prolapse repair should not adversely affect the good results of mesh abdominal wall hernia repair. New Zealand general surgeons are well trained in providing modern hernia surgery.

  3. Mechanical behaviour of synthetic surgical meshes: finite element simulation of the herniated abdominal wall.

    PubMed

    Hernández-Gascón, B; Peña, E; Melero, H; Pascual, G; Doblaré, M; Ginebra, M P; Bellón, J M; Calvo, B

    2011-11-01

    The material properties of meshes used in hernia surgery contribute to the overall mechanical behaviour of the repaired abdominal wall. The mechanical response of a surgical mesh has to be defined since the haphazard orientation of an anisotropic mesh can lead to inconsistent surgical outcomes. This study was designed to characterize the mechanical behaviour of three surgical meshes (Surgipro®, Optilene® and Infinit®) and to describe a mechanical constitutive law that accurately reproduces the experimental results. Finally, through finite element simulation, the behaviour of the abdominal wall was modelled before and after surgical mesh implant. Uniaxial loading of mesh samples in two perpendicular directions revealed the isotropic response of Surgipro® and the anisotropic behaviour of Optilene® and Infinit®. A phenomenological constitutive law was used to reproduce the measured experimental curves. To analyze the mechanical effect of the meshes once implanted in the abdomen, finite element simulation of the healthy and partially herniated repaired rabbit abdominal wall served to reproduce wall behaviour before and after mesh implant. In all cases, maximal displacements were lower and maximal principal stresses higher in the implanted abdomen than the intact wall model. Despite the fact that no mesh showed a behaviour that perfectly matched that of abdominal muscle, the Infinit® mesh was able to best comply with the biomechanics of the abdominal wall. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Abdominal wall desmoid tumors: A case report

    PubMed Central

    MA, JIN-HUI; MA, ZHEN-HAI; DONG, XUE-FENG; YIN, HANG; ZHAO, YONG-FU

    2013-01-01

    Desmoid tumors (DTs) are rare lesions that do not possess any metastatic potential. However, they have a strong tendency to invade locally and recur. They constitute 3% of all soft tissue tumors and 0.03% of all neoplasms. Abdominal DTs occur sporadically or are associated with certain familial syndromes, such as familial adenomatous polyposis (FAP). The single form of this neoplasm most frequently occurs in females of reproductive age and during pregnancy. A female patient with a DT of the abdominal wall who had no relevant family history was admitted to hospital. The patient, who presented with a painless mass in the left anterolateral abdomen, had no history of trauma, surgery or childbearing. According to the medical history, physical examination and CT report, the patient was diagnosed with DT. Radical resection of the affected abdominal wall musculature was performed, and the defect was replaced with a polypropylene mesh. The histological diagnosis was of DT. The patient remains in good health and complete remission without any other treatment following surgery. DTs exhibit aggressive growth and have a high rate of recurrence. Surgery is the optimal treatment, and subsequent radiotherapy may decrease the local recurrence rate. Further research into their aetiology is required combined with multicentre clinical trials of new treatments in order to improve management of this disease. This case report provides general knowledge of DT, and may be used as a guidance for diagnosis and treatment. PMID:23833679

  5. Bioprosthetic tissue matrices in complex abdominal wall reconstruction.

    PubMed

    Broyles, Justin M; Abt, Nicholas B; Sacks, Justin M; Butler, Charles E

    2013-12-01

    Complex abdominal defects are difficult problems encountered by surgeons in multiple specialties. Although current evidence supports the primary repair of these defects with mesh reinforcement, it is unclear which mesh is superior for any given clinical scenario. The purpose of this review was to explore the characteristics of and clinical relevance behind bioprosthetic tissue matrices in an effort to better clarify their role in abdominal wall reconstruction. We reviewed the peer-reviewed literature on the use of bioprosthetic mesh in human subjects. Basic science articles and large retrospective and prospective reviews were included in author's analysis. The clinical performance and characteristics of 13 bioprosthetic tissue matrices were evaluated. The majority of the products evaluated perform well in contaminated fields, where the risk of wound-healing difficulties is high. Clinical outcomes, which included infection, reherniation, and bulge formation, were variable, and the majority of the studies had a mean follow-up of less than 24 months. Although bioprosthetic matrix has a multitude of indications within the growing field of abdominal wall reconstruction, the functionality, regenerative capacity, and long-term fate of these products have yet to be fully established. Furthermore, the clinical performance, indications, and contraindications for each type of matrix need to be fully evaluated in long-term outcome studies.

  6. Role of tissue expansion in abdominal wall reconstruction: A systematic evidence-based review.

    PubMed

    Wooten, Kimberly E; Ozturk, Cemile Nurdan; Ozturk, Can; Laub, Peter; Aronoff, Nell; Gurunluoglu, Raffi

    2017-06-01

    Tissue expanders (TEs) can be used to assist primary closure of complicated hernias and large abdominal wall defects. However, there is no consensus regarding the optimal technique, use, or associated risk of TE in abdominal wall reconstruction. A systematic search of PubMed and Embase databases was conducted to identify articles reporting abdominal wall reconstruction with TE techniques. English articles published between 1980 and 2016 were included on the basis of the following inclusion criteria: two-stage TE surgical technique, >3 cases, reporting of postoperative complications, hernia recurrence, and patient-based clinical data. Fourteen studies containing 103 patients (85 adults and 18 children) were identified for analysis. Most patients presented with a skin-grafted ventral hernia (n = 86). The etiology of the hernia was from trauma or prior abdominal surgery. The remaining patients had TE placed before organ transplantation (n = 12) or for congenital abdominal wall defects (n = 5). The location for expander placement was subcutaneous (n = 74), between the internal and external obliques (n = 26), posterior to the rectus sheath (n = 2), and intra-peritoneal (n = 1). Postoperative infections and implant-related problems were the most commonly reported complications after Stage I. The most common complication after Stage II was recurrent hernia, which was observed in 12 patients (11.7%). Five patients with TE died. Complications and mortality were more prevalent in children, immunosuppressed patients, and those with chronic illnesses. Tissue expansion for abdominal wall reconstruction can be successfully used for a variety of carefully selected patients with an acceptable complication and risk profile. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. Characterization of the anisotropic mechanical behavior of human abdominal wall connective tissues.

    PubMed

    Astruc, Laure; De Meulaere, Maurice; Witz, Jean-François; Nováček, Vit; Turquier, Frédéric; Hoc, Thierry; Brieu, Mathias

    2018-06-01

    Abdominal wall sheathing tissues are commonly involved in hernia formation. However, there is very limited work studying mechanics of all tissues from the same donor which prevents a complete understanding of the abdominal wall behavior and the differences in these tissues. The aim of this study was to investigate the differences between the mechanical properties of the linea alba and the anterior and posterior rectus sheaths from a macroscopic point of view. Eight full-thickness human anterior abdominal walls of both genders were collected and longitudinal and transverse samples were harvested from the three sheathing connective tissues. The total of 398 uniaxial tensile tests was conducted and the mechanical characteristics of the behavior (tangent rigidities for small and large deformations) were determined. Statistical comparisons highlighted heterogeneity and non-linearity in behavior of the three tissues under both small and large deformations. High anisotropy was observed under small and large deformations with higher stress in the transverse direction. Variabilities in the mechanical properties of the linea alba according to the gender and location were also identified. Finally, data dispersion correlated with microstructure revealed that macroscopic characterization is not sufficient to fully describe behavior. Microstructure consideration is needed. These results provide a better understanding of the mechanical behavior of the abdominal wall sheathing tissues as well as the directions for microstructure-based constitutive model. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Clinical evaluation of extraperitoneal colostomy without damaging the muscle layer of the abdominal wall.

    PubMed

    Dong, L-R; Zhu, Y-M; Xu, Q; Cao, C-X; Zhang, B-Z

    2012-01-01

    This study investigated whether extraperitoneal colostomy without damaging the muscle layer of the abdominal wall is an improved surgical procedure compared with conventional sigmoid colostomy in patients undergoing abdominoperineal resection. Patients with rectal cancer undergoing abdominoperineal resection were selected and randomly divided into two groups: the study group received extraperitoneal colostomy without damaging the muscle layer of the abdominal wall and the control group received conventional colostomy. Clinical data from both groups were analysed. A total of 128 patients were included: 66 received extraperitoneal colostomy without damaging the muscle layer of the abdominal wall and 62 received conventional colostomy. Significant differences between the two groups were found in relation to colostomy operating time, defaecation sensation, bowel control and overall stoma-related complications. Duration of postoperative hospital stay was also significantly different between the study groups. Extraperitoneal colostomy without damaging the muscle layer of the abdominal wall was found to be an improved procedure compared with conventional sigmoid colostomy in abdominoperineal resection, and may reduce colostomy-related complications, shorten operating time and postoperative hospital stay, and potentially improve patients' quality of life.

  9. [Prophylactics and treatment of postoperative hernias of the lateral abdominal walls using polypropylene endoprosthesis].

    PubMed

    Sukovatykh, B S; Valuĭskaia, N M; Pravednikova, N V; Netiaga, A A; Kas'ianova, M A; Zhukovskiĭ, V A

    2011-01-01

    An analysis of complex examination and treatment of 151 patients after planned and performed surgical interventions on organs of the retroperitoneal space was made. The patients were divided into 4 groups. The first group (of comparison) included 46 patients who were treated by lumbotomy for different diseases of organs of the urinary system. In 35 patients of the second group (prophylactics) the indications were determined and in 20 patients preventive endoprosthesis of the lateral abdominal wall using polypropylene endoprosthesis was fulfilled. Herniotomy with plasty of the lateral abdominal wall using local tissues was fulfilled in 30 patients. Prosthesing hernioplasty of the lateral abdominal wall was fulfilled in 40 patients of the main group. It was found that preventive endoprosthesis of the lateral abdominal wall allowed prevention of progressing anatomo-functional i/isufficiency and the appearance of postoperative hernias. The application of polypropylene endoprosthesis for the treatment of postoperative hernias allows obtaining 36.4% more good results as compared with the control group, 21.7% decreased number of satisfactory results and no recurrent hernias.

  10. Towards the mechanical characterization of abdominal wall by inverse analysis.

    PubMed

    Simón-Allué, R; Calvo, B; Oberai, A A; Barbone, P E

    2017-02-01

    The aim of this study is to characterize the passive mechanical behaviour of abdominal wall in vivo in an animal model using only external cameras and numerical analysis. The main objective lies in defining a methodology that provides in vivo information of a specific patient without altering mechanical properties. It is demonstrated in the mechanical study of abdomen for hernia purposes. Mechanical tests consisted on pneumoperitoneum tests performed on New Zealand rabbits, where inner pressure was varied from 0mmHg to 12mmHg. Changes in the external abdominal surface were recorded and several points were tracked. Based on their coordinates we reconstructed a 3D finite element model of the abdominal wall, considering an incompressible hyperelastic material model defined by two parameters. The spatial distributions of these parameters (shear modulus and non linear parameter) were calculated by inverse analysis, using two different types of regularization: Total Variation Diminishing (TVD) and Tikhonov (H 1 ). After solving the inverse problem, the distribution of the material parameters were obtained along the abdominal surface. Accuracy of the results was evaluated for the last level of pressure. Results revealed a higher value of the shear modulus in a wide stripe along the craneo-caudal direction, associated with the presence of linea alba in conjunction with fascias and rectus abdominis. Non linear parameter distribution was smoother and the location of higher values varied with the regularization type. Both regularizations proved to yield in an accurate predicted displacement field, but H 1 obtained a smoother material parameter distribution while TVD included some discontinuities. The methodology here presented was able to characterize in vivo the passive non linear mechanical response of the abdominal wall. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Morphology of the abdominal wall in the bat, Pteronotus parnellii (Microchiroptera: Mormoopidae): implications for biosonar vocalization.

    PubMed

    Lancaster, W C; Henson, O W

    1995-01-01

    We investigated the structure of the abdominal wall of Pteronotus parnellii and made comparisons with eight other species of Microchiroptera and one megachiropteran. Similar to other mammals, the abdominal wall of bats consists of the three flank muscles laterally and the m. rectus abdominis ventrally. In Microchiroptera, flank muscles are mostly confined to dorsal portions of the wall. The mm. transversus abdominis and obliquus internus abdominis form the bulk of the wall; the m. obliquus externus is poorly developed. Ventrolaterally, a large portion of the wall is a dense, bilaminar aponeurosis, composed of collagen, elastin, and fibroblasts. The thicker, superficial lamina derives from the mm. obliquus internus and transversus abdominis. The deep lamina is a continuation of the transversalis fascia. Collagen fibers of the two fused laminae are oriented orthogonally, resulting in a resilient, composite fabric. Fascicles of the flank muscles are oriented along the margins of the aponeurosis so that their forces appear to be concentrated onto the aponeurosis. We suggest that this system is adapted for the regulation and generation of intra-abdominal pressure. The abdominal wall of Pteropus, the one megachiropteran examined, lacks the derived aponeurosis and is similar to other mammals. We consider the abdominal wall of Microchiroptera to be analogous to the diaphragma, in that it functions in the regulation of pressure within body cavities and facilitates biosonar vocalization.

  12. Grey Turner's and Cullen's signs induced by spontaneous hemorrhage of the abdominal wall after coughing.

    PubMed

    Fan, Zhe; Zhang, Yingyi

    2017-08-01

    Grey Turner's and Cullen's signs are rare clinical signs, which most appear in patients with severe acute pancreatitis. The present patient complained of abdominal pain after coughing. However, contrast-enhanced CT revealed a hemorrhage of the abdominal wall. Therefore, spontaneous hemorrhage of the abdominal wall was diagnosed. The patient recovered through immobilization and hemostasis therapy. This case report and literature review aims to remind clinicians of manifestations and treatment of spontaneous hemorrhage.

  13. Bioprosthetic Tissue Matrices in Complex Abdominal Wall Reconstruction

    PubMed Central

    Broyles, Justin M.; Abt, Nicholas B.; Sacks, Justin M.

    2013-01-01

    Background: Complex abdominal defects are difficult problems encountered by surgeons in multiple specialties. Although current evidence supports the primary repair of these defects with mesh reinforcement, it is unclear which mesh is superior for any given clinical scenario. The purpose of this review was to explore the characteristics of and clinical relevance behind bioprosthetic tissue matrices in an effort to better clarify their role in abdominal wall reconstruction. Methods: We reviewed the peer-reviewed literature on the use of bioprosthetic mesh in human subjects. Basic science articles and large retrospective and prospective reviews were included in author’s analysis. The clinical performance and characteristics of 13 bioprosthetic tissue matrices were evaluated. Results: The majority of the products evaluated perform well in contaminated fields, where the risk of wound-healing difficulties is high. Clinical outcomes, which included infection, reherniation, and bulge formation, were variable, and the majority of the studies had a mean follow-up of less than 24 months. Conclusions: Although bioprosthetic matrix has a multitude of indications within the growing field of abdominal wall reconstruction, the functionality, regenerative capacity, and long-term fate of these products have yet to be fully established. Furthermore, the clinical performance, indications, and contraindications for each type of matrix need to be fully evaluated in long-term outcome studies. PMID:25289285

  14. Autocalibrating motion-corrected wave-encoding for highly accelerated free-breathing abdominal MRI.

    PubMed

    Chen, Feiyu; Zhang, Tao; Cheng, Joseph Y; Shi, Xinwei; Pauly, John M; Vasanawala, Shreyas S

    2017-11-01

    To develop a motion-robust wave-encoding technique for highly accelerated free-breathing abdominal MRI. A comprehensive 3D wave-encoding-based method was developed to enable fast free-breathing abdominal imaging: (a) auto-calibration for wave-encoding was designed to avoid extra scan for coil sensitivity measurement; (b) intrinsic butterfly navigators were used to track respiratory motion; (c) variable-density sampling was included to enable compressed sensing; (d) golden-angle radial-Cartesian hybrid view-ordering was incorporated to improve motion robustness; and (e) localized rigid motion correction was combined with parallel imaging compressed sensing reconstruction to reconstruct the highly accelerated wave-encoded datasets. The proposed method was tested on six subjects and image quality was compared with standard accelerated Cartesian acquisition both with and without respiratory triggering. Inverse gradient entropy and normalized gradient squared metrics were calculated, testing whether image quality was improved using paired t-tests. For respiratory-triggered scans, wave-encoding significantly reduced residual aliasing and blurring compared with standard Cartesian acquisition (metrics suggesting P < 0.05). For non-respiratory-triggered scans, the proposed method yielded significantly better motion correction compared with standard motion-corrected Cartesian acquisition (metrics suggesting P < 0.01). The proposed methods can reduce motion artifacts and improve overall image quality of highly accelerated free-breathing abdominal MRI. Magn Reson Med 78:1757-1766, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  15. Complicated acute appendicitis presenting as a rapidly progressive soft tissue infection of the abdominal wall: a case report.

    PubMed

    Beerle, Corinne; Gelpke, Hans; Breitenstein, Stefan; Staerkle, Ralph F

    2016-12-01

    We report a case of a rare complication of acute appendicitis with perforation through the abdominal wall. The case points out that an intraabdominal origin should be considered in patients presenting with rapidly spreading soft tissue infections of the trunk. A 58-year-old European woman presented to our hospital with a 1-week history of severe abdominal pain accompanied by rapidly spreading erythema and emphysema of the lower abdomen. On admission, the patient was in septic shock with leukocytosis and elevation of C-reactive protein. Among other diagnoses, necrotizing fasciitis was suspected. Computed tomography showed a large soft tissue infection with air-fluid levels spreading through the lower abdominal wall. During the operation, we found a perforated appendicitis breaking through the fascia and causing a rapidly progressive soft tissue infection of the abdominal wall. Appendicitis was the origin of the soft tissue infection. The abdominal wall was only secondarily involved. Even though perforated appendicitis as an etiology of a rapidly progressive soft tissue infection of the abdominal wall is very rare, it should be considered in the differential diagnosis of abdominal wall cellulitis. The distinction between rapidly spreading subcutaneous infection with abscess formation and early onset of necrotizing fasciitis is often difficult and can be confirmed only by surgical intervention.

  16. Bovine versus porcine acellular dermal matrix for complex abdominal wall reconstruction.

    PubMed

    Clemens, Mark W; Selber, Jesse C; Liu, Jun; Adelman, David M; Baumann, Donald P; Garvey, Patrick B; Butler, Charles E

    2013-01-01

    Abdominal wall reconstruction with bioprosthetic mesh is associated with lower rates of mesh infection, fistula formation, and mesh explantation than reconstruction with synthetic mesh. The authors directly compared commonly used bioprosthetic meshes in terms of clinical outcomes and complications. A database of consecutive patients who underwent abdominal wall reconstruction with porcine or bovine acellular dermal matrix and midline musculofascial closure at their institution between January of 2008 and March of 2011 was reviewed. Surgical outcomes were compared. One hundred twenty patients were identified who underwent a nonbridged, inlay abdominal wall reconstruction with porcine [69 patients (57.5 percent)] or bovine acellular dermal matrix (51 patients (42.5 percent)]. The mean follow-up time was 21.0 ± 9.9 months. The overall complication rate was 36.6 percent; the porcine matrix group had a significantly higher complication rate (44.9 percent) than the bovine matrix group (25.5 percent; p = 0.04) and statistically equivalent surgical complications (29.2 percent versus 21.6 percent; p = 0.34). There were no significant differences in rates of recurrent hernia (2.9 percent versus 3.9 percent; p = 0.99) or bulge (7.2 percent versus 0 percent; p = 0.07). However, the rate of intraoperative adverse events in the porcine matrix group [seven events (10.1 percent)] was significantly higher than that in the bovine matrix group (0 percent; p = 0.02). In patients who undergo complex abdominal wall reconstruction, both bovine and porcine acellular dermal matrix are associated with similar rates of postoperative surgical complications and appear to result in similar outcomes. Porcine acellular dermal matrix may be prone to intraoperative device failure. Therapeutic, III.

  17. Theory of Current-Driven Domain Wall Motion

    NASA Astrophysics Data System (ADS)

    Tatara, Gen

    2004-03-01

    Current-induced motion of a domain wall is studied starting from a microscopic Hamiltonian with an exchange interaction between conduction electrons and spins of the wall [1]. With a key observation that the position X and the angle φ0 the wall magnetization forms with the easy plane are the proper collective coordinates to describe its dynamics, it follows straightforwardly that the electric current affects the wall motion in two different ways, in agreement with Berger's pioneering observations[2]. The first is as a force, or momentum transfer, due to the reflection of conduction electrons. This force is proportional to the charge current j and wall resistivity ρ_w, and hence becomes important in thin walls. The other is as a spin torque or spin transfer[3], which is dominant for thick walls where the spin of conduction electron follows the magnetization adiabatically. The motion of a domain wall under a steady current is studied in two limiting cases. In the adiabatic case, we show that even without a pinning force, there is a threshold spin current, j_s^cr∝ K_⊥λ, below which the wall does not move (K_⊥ and λ being the hard-axis magnetic anisotropy and wall thickness, respectively). Below the threshold, the transferred angular momentum is used to shift φ0 and not to the wall motion. The pinning potential V0 affects j_s^cr only if it is very strong, V0 > K_⊥/α, where α is the damping parameter in the Landau-Lifshits-Gilbert equation. Therefore, the critical current for the adiabatic wall does not suffer very much from weak pinning, which is consistent with experimental observations[4]. The wall velocity after depinning is found to be ∝[(j_s/j_s^cr)^2-1]^1/2. In the case of thin wall, driven by a force ∝ ρw j, the critical current density is given by j^cr∝ V_0/ρ_w. In nanocontacts, this is estimated to be ˜ 10^7[A/m^2]. This small critical current would be advantageous for device application. [1] G.Tatara and H.Kohno, cond-mat/0308464

  18. 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).

  19. The use of ultrasound in the diagnosis of abdominal wall hernias.

    PubMed

    Young, J; Gilbert, A I; Graham, M F

    2007-08-01

    The diagnosis of abdominal wall hernias is not always straightforward and may require additional investigative modalities. Real-time ultrasound is accurate, non-invasive, relatively inexpensive, and readily available. The value of ultrasound as an adjunctive tool in the diagnosis of abdominal wall hernias in both pre-operative and post-operative patients was studied. Retrospective analysis of 200 patients treated at the Hernia Institute of Florida was carried out. In these cases, ultrasound had been used to assist with case management. Patients without previous hernia surgery and those with early and late post-herniorrhaphy complaints were studied. Patients with obvious hernias were excluded. Indications for ultrasound examination included patients with abdominal pain without a palpable hernia, a palpable mass of questionable etiology, and patients with inordinate pain or excessive swelling during the early post-operative period. Patients were treated with surgery or conservative therapy depending on the results of the physical examination and ultrasound studies. Cases in which the ultrasound findings influenced the decision-making process by confirming clinical findings or altering the diagnosis and changing the treatment plan are discussed. Of the 200 patients, 144 complained of pain alone and on physical exam no hernia or mass was palpable. Of these 144 patients with pain alone, 21 had a hernia identified on the US examination and were referred for surgery. The 108 that had a negative ultrasound were treated conservatively with rest, heat, and anti-inflammatory drugs, most often with excellent results. Of the 56 remaining patients who had a mass, with or without pain, 22 had hernias identified by means of ultrasound examination. In the other 34, the etiology of the mass was not a hernia. Abdominal wall ultrasound is a valuable tool in the scheme of management of patients in whom the diagnosis of abdominal wall hernia is unclear. Therapeutic decisions can be

  20. Temporal analysis of regional wall motion from cine cardiac MRI

    NASA Astrophysics Data System (ADS)

    Ratib, Osman M.; Didier, Dominique; Chretien, Anne; Rosset, Antoine; Magnin, Isabelle E.; Ligier, Yves

    1996-04-01

    The purpose of this work is to develop and to evaluate an automatic analysis technique for quantitative assessment of cardiac function from cine MRI and to identify regional alterations in synchronicity based on Fourier analysis of ventricular wall motion (WM). A temporal analysis technique of left ventricular wall displacement was developed for quantitative analysis of temporal delays in wall motion and applied to gated cine 'dark blood' cardiac MRI. This imaging technique allows the user to saturate the blood both above and below the imaging slice simultaneously by using a specially designed rf presaturation pulse. The acquisition parameters are: TR equals 25 - 60 msec, TE equals 5 - 7 msec, 0 equals 25 degrees, slice thickness equals 10 mm, 16 to 32 frames/cycle. Automatic edge detection was used to outline the ventricular cavities on all frames of a cardiac cycle. Two different segmentation techniques were applied to all studies and lead to similar results. Further improvement in edge detection accuracy was achieved by temporal interpolation of individual contours on each image of the cardiac cycle. Radial analysis of the ventricular wall motion was then performed along 64 radii drawn from the center of the ventricular cavity. The first harmonic of the Fourier transform of each radial motion curve is calculated. The phase of the fundamental Fourier component is used as an index of synchrony (delay) of regional wall motion. Results are displayed in color-coded maps of regional alterations in the amplitude and synchrony of wall motion. The temporal delays measured from individual segments are evaluated through a histogram of phase distribution, where the width of the main peak is used as an index of overall synchrony of wall motion. The variability of this technique was validated in 10 normal volunteers and was used to identify regions with asynchronous WM in 15 patients with documented CAD. The standard deviation (SD) of phase distribution measured in short axis

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nakamura, Mitsuhiro; Narita, Yuichiro; Matsuo, Yukinori

    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 onemore » 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.« less

  2. Investigation into the optimal prosthetic material for wound healing of abdominal wall defects

    PubMed Central

    Akcakaya, Adem; Aydogdu, Ibrahim; Citgez, Bulent

    2018-01-01

    The purpose of this experimental study is to investigate and compare the effects of prosthetic materials used for wound healing of abdominal wall hernias. A total of 60 rats were divided into five equal groups: Group I, control subjected to laparotomy; group II, abdominal wall defect 3×2 cm+polypropylene (PP) mesh; group III, abdominal wall defect 3×2 cm+PP mesh+hyaluronate and carboxymethylcellulose (H-CMC; Seprafilm®); group IV, abdominal wall defect 3×2 cm+polytetrafluoroethylene (PTFE; Composix™); and group V, abdominal wall defect 3×2 cm+polyethylene terephthalate (PET; Dacron®). A total of 14 days after the surgery, rats were sacrificed and the meshes with the surrounding tissue were extracted in block. The breaking strength of the mesh from the fascia was recorded. The healing tissue was examined with the index of histopathology and the hydroxyproline value was analyzed using the Switzer method. Both the breaking strength and histopathological index of the wound healing were significantly improved in groups II and III compared with that in groups IV and V (P<0.001). Hydroxyproline values were the highest in group I (P<0.001). There was also a statistically significant difference between groups II and IV, and group V and the other groups (P<0.001). The present findings demonstrated that PP mesh and PP mesh+H-CMC had a superior breaking strength and improved histopathologic indices compared with PTFE and PET. Furthermore, hydroxyproline values were the lowest in the PET group. In conclusion, wound healing was improved in the PP mesh group and the PP mesh+H-CMC group compared with the PTFE and PET groups according to the present study parameters. PMID:29399133

  3. 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.

  4. Outcomes of abdominal wall reconstruction with acellular dermal matrix are not affected by wound contamination.

    PubMed

    Garvey, Patrick B; Martinez, Roberto A; Baumann, Donald P; Liu, Jun; Butler, Charles E

    2014-11-01

    The optimal type of mesh for complex abdominal wall reconstruction has not been elucidated. We hypothesized that AWRs using acellular dermal matrix (ADM) experience low rates of surgical site occurrence (SSO) and surgical site infection, despite increasing degrees of wound contamination. We retrospectively reviewed prospectively collected data from consecutive abdominal wall reconstructions with ADM over a 9-year period. Outcomes of abdominal wall reconstructions were compared between patients with different CDC wound classifications. Univariate and multivariate logistic regression and Cox proportional hazard regression analyses identified potential associations and predictive/protective factors. The 359 patients had a mean follow-up of 28.3 ± 19.0 months. Reconstruction of clean wounds (n = 171) required fewer reoperations than that of combined contaminated (n = 188) wounds (2.3% vs 11.2%; p = 0.001) and trended toward experiencing fewer SSOs (19.9% vs 28.7%, p = 0.052). There were no significant differences between clean and combined contaminated cases in 30-day SSI (8.8% vs 8.0%), hernia recurrence (9.9% vs 10.1%), and mesh removal (1.2% vs 1.1%) rates. Independent predictors of SSO included body mass index ≥30 kg/m(2) (odds ratio [OR] 3.6; p < 0.001), 1 or more comorbidities (OR 2.5; p = 0.008), and defect width ≥15 cm (OR 1.8; p = 0.02). Complex abdominal wall reconstructions using ADM demonstrated similar rates of complications between the different CDC wound classifications. This is in contradistinction to published outcomes for abdominal wall reconstruction using synthetic mesh that show progressively higher complication rates with increasing degrees of contamination. These data support the use of ADM rather than synthetic mesh for complex abdominal wall reconstruction in the setting of wound contamination. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Abdominal Wall Endometriosis: Myofibroblasts as a Possible Evidence of Metaplasia: A Case Report.

    PubMed

    Ibrahim, Mohamed Gamal; Delarue, Eleonore; Abesadze, Elene; Haas, Matthias; Sehouli, Jalid; Chiantera, Vito; Mechsner, Sylvia

    2017-01-01

    In this study, we report about a patient with extra-uterine endometriosis (EM) in the abdominal wall muscle with evident metaplasia based on the abundant alpha smooth muscle actin (ASMA)-expressing myofibroblasts. Laparotomy excision of the abdominal wall EM was done following ultrasonographic evidence of a hypodense swelling in the right rectus abdominis, which was confirmed by MRI. Immunohistochemistry staining for ASMA and collagen I was done, with the results confirming that endometriotic stromal cells expressed both. Anterior abdominal wall endometriosis was suspected because of the patient's history of recurrent EM combined with the cyclic nature of symptoms. MRI is useful in determining the extent of the disease. In case of persisting symptoms even under hormonal treatment, surgical excision is mandatory. The expression of both ASMA and collagen I in and around EM lesions supports the notion of the metaplastic process in the course of disease development. © 2016 S. Karger AG, Basel.

  6. Magnetization reversal in ferromagnetic spirals via domain wall motion

    NASA Astrophysics Data System (ADS)

    Schumm, Ryan D.; Kunz, Andrew

    2016-11-01

    Domain wall dynamics have been investigated in a variety of ferromagnetic nanostructures for potential applications in logic, sensing, and recording. We present a combination of analytic and simulated results describing the reliable field driven motion of a domain wall through the arms of a ferromagnetic spiral nanowire. The spiral geometry is capable of taking advantage of the benefits of both straight and circular wires. Measurements of the in-plane components of the spirals' magnetization can be used to determine the angular location of the domain wall, impacting the magnetoresistive applications dependent on the domain wall location. The spirals' magnetization components are found to depend on the spiral parameters: the initial radius and spacing between spiral arms, along with the domain wall location. The magnetization is independent of the parameters of the rotating field used to move the domain wall, and therefore the model is valid for current induced domain wall motion as well. The speed of the domain wall is found to depend on the frequency of the rotating driving field, and the domain wall speeds can be reliably varied over several orders of magnitude. We further demonstrate a technique capable of injecting multiple domain walls and show the reliable and unidirectional motion of domain walls through the arms of the spiral.

  7. 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

  8. Abdominal wall abscess secondary to spontaneous rupture of pyogenic liver abscess.

    PubMed

    Zizzo, Maurizio; Zaghi, Claudia; Manenti, Antonio; Luppi, Davide; Ugoletti, Lara; Bonilauri, Stefano

    2016-01-01

    Pyogenic liver abscess is a rare cause of hospitalization, related to a mortality rate ranging between 15% and 19%. Treatment of choice is represented by image-guided percutaneous drainage in combination with antibiotic therapy but, in some selected cases, surgical treatment is necessary. In extremely rare cases, spontaneous rupture of liver abscess may occur, free in the peritoneal cavity or in neighboring organs, an event which is generally considered a surgical emergency. A 95-years-old woman was hospitalized with fever, upper abdominal pain, mild dyspepsia and massive swelling of the anterior abdominal wall. Computed tomography revealed an oval mass located in the abdominal wall of 12cm×14cm×7cm, in continuity with an abscess of the left hepatic lobe. Because Proteus mirabilis was detected in both the liver abscess and the abdominal wall abscess, the patient was diagnosed with a ruptured pyogenic liver abscess. After spontaneous drainage to the exterior of the hepato-parietal abscess, she was successfully treated with antibiotics alone. Pyogenic liver abscess is a serious and life-threatening illness. Abscess rupture might occur. Many authors consider this complication a surgical emergency, but the site of abscess rupture changes the clinical history of the disease: in case of free rupture into the peritoneum, emergency surgery is mandatory, while a rupture localized in neighboring tissues or organs can be successfully treated by a combination of systemic antibiotics and fine needle aspiration and/or percutaneous drainage of the abscess. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. [Experience with Clotteau-Prémont's technique in abdominal wall hernias. Preliminary report].

    PubMed

    Soto-Dávalos, Baltazar Alberto; Del Pozzo-Magaña, José Antonio; Luna-Martínez, Javier

    2006-01-01

    Incisional hernias account for at least a third of abdominal wall hernias. There are different techniques of repair that include the use of prosthetic materials, which has lowered the hernia recurrence rate. Nonetheless, its use in case of rejection or infection requires other techniques with local tissue. The use of prosthetic material in a contaminated environment is contraindicated because the risk of infection and recurrence rate is unacceptably high. In order to compare two repair techniques for abdominal wall hernias in terms of complications and recurrence to be used as an alternative for hernia repair in patients with abdominal wall hernias, we conducted, between January 2000 and January 2004, an observational, longitudinal, retrospective, non-randomized matched control case study in patients with abdominal wall hernia. A total of 30 patients were studied and were divided into two groups of 15 patients each. Subjects were matched for sex, age and hernia type (group A, mesh treated and group B, Clotteau-Prémont treated) who had at least a 5-month postoperative follow-up. Complication and recurrence rate was assessed and compared. There were no differences between the two groups in complications or recurrence (p <0.05). The average follow-up time was 18.9 +/- 8 months for group A and 15 +/- 7.9 months for group B. Clotteau-Prémont's technique is a safe and feasible alternative procedure with indications in selected patients.

  10. Abdominal wall Hydatid cyst: A review a literature with a case report.

    PubMed

    Salih, Abdulwahid M; Kakamad, F H; Hammood, Zuhair D; Yasin, Bzhwen; Ahmed, Dilshad M

    2017-01-01

    Hydatid cyst (HC) disease is a serious health problem in endemic areas. It is a parasitic infection that commonly involves liver and lungs while muscular HC is rare. HC of abdominal wall was reported only six times. We reported a 39-year-old male presented with HC of the right loin who was managed surgically with brief literature review. HC should be put in the differential diagnosis of the abdominal wall masses. Its pre-operative diagnosis is important to prevent rupture with subsequent anaphylaxis and recurrence. Surgery is the main modality of treatment. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  11. Catheter enterostomy and patch repair of the abdominal wall for gastroschisis with intestinal atresia: report of a case.

    PubMed

    Ohno, Koichi; Nakamura, Tetsuro; Azuma, Takashi; Yoshida, Tatsuyuki; Yamada, Hiroto; Hayashi, Hiroaki; Masahata, Kazunori

    2009-01-01

    A male infant, weighing 2177 g, was born with the entire intestine protruding through a defect on the right side of the navel. Intestinal atresia, approximately 70 cm from the Treitz ligament, was also confirmed. Primary anastomosis and abdominal wall repair were impossible because of the intestinal dilation and thick peel, as well as the small abdominal cavity. Thus, we initially performed catheter enterostomy with a 14-F balloon catheter and patch repair of the abdominal wall, to enable the baby to be fed. Secondary anastomosis and abdominal wall repair was safely performed when the baby was 106 days old. The combination of catheter enterostomy and patch repair of the abdominal wall does not require dissection of the intestine and it can be safely performed in low-birth-weight babies. It also enables feeding and weight gain, and the overlying skin prevents contamination of the artificial sheet. We recommend this combination for neonates with both gastroschisis and intestinal atresia.

  12. Whole abdominal wall segmentation using augmented active shape models (AASM) with multi-atlas label fusion and level set

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    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.

  13. Use of human and porcine dermal-derived bioprostheses in complex abdominal wall reconstructions: a literature review and case report.

    PubMed

    Baillie, Daniel R; Stawicki, S Peter; Eustance, Nicole; Warsaw, David; Desai, Darius

    2007-05-01

    The goal of abdominal wall reconstruction is to restore and maintain abdominal domain. A PubMed(R) review of the literature (including "old" MEDLINE through February 2007) suggests that bioprosthetic materials are increasingly used to facilitate complex abdominal wall reconstruction. Reported results (eight case reports/series involving 137 patients) are encouraging. The most commonly reported complications are wound seroma (18 patients, 13%), skin dehiscence with graft exposure without herniation (six, 4.4%), superficial and deep wound infections (five, 3.6%), hernia recurrence (four, 2.9%), graft failure with dehiscence (two), hematoma (two), enterocutaneous fistula (one), and flap necrosis (one). Two recent cases are reported herein. In one, a 46-year-old woman required open abdominal management after gastric remnant perforation following a Roux-en-Y gastric bypass procedure. Porcine dermal collagen combined with cutaneous flaps was used for definitive abdominal wall reconstruction. The patient's condition improved postoperatively and she was well 5 months after discharge from the hospital. In the second, a 54-year-old woman underwent repair of an abdominal wall defect following resection of a large leiomyosarcoma. Human acellular dermis combined with myocutaneous flaps was used to reconstruct the abdominal wall defect. The patient's recovery was uncomplicated and 20 weeks following surgery she was doing well with no evidence of recurrence or hernia. The results reported to date and the outcomes presented here suggest that bioprosthetic materials are safe and effective for repair of large abdominal wall defects. Prospective, randomized, controlled studies are needed to compare the safety and efficacy of other reconstructive techniques as well as human and porcine dermal-derived bioprostheses.

  14. Segmental analysis of respiratory liver motion in patients with and without a history of abdominal surgery.

    PubMed

    Shimizu, Yasuhiro; Takamatsu, Shigeyuki; Yamamoto, Kazutaka; Maeda, Yoshikazu; Sasaki, Makoto; Tamamura, Hiroyasu; Bou, Sayuri; Kumano, Tomoyasu; Gabata, Toshifumi

    2018-06-20

    The purpose of this study was to analyze the respiratory motion of each segment of the liver in patients with or without a history of abdominal surgery using four-dimensional computed tomography. In total, 57 patients treated for abdominal tumors using proton beam therapy were enrolled. Eighteen patients had a history of abdominal surgery and 39 did not. The positions of clearly demarcated, high-density regions in the liver were measured as evaluation points with which to quantify the motion of each liver segment according to the Couinaud classification. In total, 218 evaluation points were analyzed. Comparison of differences in the motion of individual liver segments showed that among patients without a history of surgery, the maximum was 29.0 (7.2-42.1) mm in S6 and the minimum was 15.1 (10.6-19.3) mm in S4. Among patients with a history of surgery, the maximum was 28.0 (9.0-37.4) mm in S7 and the minimum was 6.3 (4.1-9.3) mm in S3. The distances and directions of respiratory motion differed for each liver segment, and a history of abdominal surgery reduced the respiratory motion of the liver. It is necessary to selectively use the internal margin setting.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Jaehak; Yoo, Myoung-Woo; Kim, Sang-Koog, E-mail: sangkoog@snu.ac.kr

    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 completemore » 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.« less

  16. Evaluation of a new composite prosthesis for the repair of abdominal wall defects.

    PubMed

    Losi, Paola; Munaò, Antonella; Spiller, Dario; Briganti, Enrica; Martinelli, Ilaria; Scoccianti, Marco; Soldani, Giorgio

    2007-10-01

    The degree of integration of biomaterials used in the repair of abdominal wall defects seems to depend upon the structure of the prosthesis. The present investigation evaluates the behaviour in terms of adhesion formation and integration of a new composite prosthesis that could be employed in this clinical application. Full-thickness abdominal wall defects (7 x 5 cm) were created in 16 anaesthetized New Zealand white rabbits and the prosthesis were placed in direct contact with the visceral peritoneum during the experiment. The defects were repaired with a composite prosthesis or pure polypropylene mesh to establish two study groups (n = 8 each). The composite device was constituted by a polypropylene mesh physically attached to a poly(ether)urethane-polydimethylsiloxane laminar sheet. Animals were sacrificed 7, 14, 21 and 30 days after implant and prosthesis/surrounding tissue specimens subjected to light and electron microscopy. Firm adhesions were detected in the polypropylene implants, while they were not present in the composite implants. The excellent behaviour of the composite prosthesis shown in this study warrants further investigation on its use for the repair of abdominal wall defects when a prosthetic device needs to be placed in contact with the intestinal loops.

  17. Abdominal wall phlebitis due to Prevotella bivia following renal transplantation in a patient with an occluded inferior vena cava.

    PubMed

    Janssen, S; van Donselaar-van der Pant, K A M I; van der Weerd, N C; Develter, W; Bemelman, F J; Grobusch, M P; Idu, M M; Ten Berge, I J M

    2013-02-01

    Pre-existing occlusion of the inferior vena cava may complicate renal transplantation. Suppurative abdominal wall phlebitis following renal transplantation was diagnosed in a patient with pre-existing thrombosis of the inferior vena cava of unknown cause. The phlebitis developed in the subcutaneous collateral veins of the abdominal wall contra-laterally to the renal transplant. Cultures from abdominal wall micro-abscesses yielded Prevotella bivia as the causative agent. This complication has not been described before in the context of renal transplantation. The pathogenesis and management of this serious complication are discussed in this paper.

  18. SU-D-BRA-06: Duodenal Interfraction Motion with Abdominal Compression

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Witztum, A; Holyoake, D; Warren, S

    Purpose: To quantify the effect of abdominal compression on duodenal motion during pancreatic radiotherapy. Methods: Seven patients treated for pancreatic cancer were selected for analysis. Four patients were treated with abdominal compression and three without. The duodenum was contoured by the same physician on each CBCT (five CBCTs for patients with compression, four for non-compression patients). CBCTs were rigidly registered using a soft tissue match and contours were copied to the delivered plans which were all radical (BED > 50 Gy). The distance between the duodenum on the planning CT and each CBCT was quantified by calculating the root meanmore » square (RMS) distance. The DVHs of each abdominal compression patient was converted to an EQD2 DVH (alpha/beta = 10) using an in-house tool and volumes receiving at least 25, 35, 45, and 50 Gy were recorded. Results: The maximum variation in duodenal volumes on the CBCTs for the four abdominal compression patients were 19.1 cm{sup 3} (32.8%), 19.1 cm{sup 3} (20.6%), 19.9 cm{sup 3} (14.3%), and 12.9 cm{sup 3} (27.3%) compared to 15.2 cm{sup 3} (17.6%), 34.7 cm{sup 3} (83.4%), and 56 cm{sup 3} (60.2%) for non-compression patients. The average RMS distance between the duodenum on the planning CT and each CBCT for all abdominal compression patients was 0.3 cm compared to 0.7 cm for non-compressed patients. The largest (and average) difference between the planning CT and CBCTs in volume of duodenum receiving more than 25, 35, 45 and 50 Gy for abdominal compression patients was 11% (5%), 9% (3%), 9% (2%), and 6% (1%). Conclusion: Abdominal compression reduces variation in volume and absolute position of the duodenum throughout treatment. This is seen as an improvement but does not eliminate the need to consider dosimetric effects of motion. Abdominal compression is particularly useful in SBRT when only a few fractions are delivered. Alon Witztum is supported by an MRC/Gray Institute DPhil Studentship. Daniel Holyoake

  19. The effect of vessel material properties and pulsatile wall motion on the fixation of a proximal stent of an endovascular graft.

    PubMed

    Corbett, T J; Molony, D S; Callanan, A; McGloughlin, T M

    2011-01-01

    Migration is a serious failure mechanism associated with endovascular abdominal aortic aneurysm (AAA) repair (EVAR). The effect of vessel material properties and pulsatile wall motion on stent fixation has not been previously investigated. A proximal stent from a commercially available stent graft was implanted into the proximal neck of silicone rubber abdominal aortic aneurysm models of varying proximal neck stiffness (β=25.39 and 20.44). The stent was then dislodged by placing distal force on the stent struts. The peak force to completely dislodge the stent was measured using a loadcell. Dislodgment was performed at ambient pressure with no flow (NF) and during pulsatile flow (PF) at pressures of 120/80 mmHg and 140/100 mmHg to determine if pulsatile wall motions affected the dislodgement force. An imaging analysis was performed at ambient pressure and at pressures of 120 mmHg and 140 mmHg to investigate diameter changes on the model due to the radial force of the stent and internal pressurisation. Stent displacement forces were ~50% higher in the stiffer model (7.16-8.4 N) than in the more compliant model (3.67-4.21 N). The mean displacement force was significantly reduced by 10.95-12.83% from the case of NF to the case of PF at 120/80 mmHg. A further increase in pressure to 140/120 mmHg had no significant effect on the displacement force. The imaging analysis showed that the diameter in the region of the stent was 0.37 mm greater in the less stiff model at all the pressures which could reduce the fixation of the stent. The results suggest that the fixation of passively fixated aortic stents could be comprised in more compliant walls and that pulsatile motions of the wall can reduce the maximum stent fixation. Copyright © 2010 IPEM. Published by Elsevier Ltd. All rights reserved.

  20. 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

  1. Brownian motion and entropic torque driven motion of domain walls in antiferromagnets

    NASA Astrophysics Data System (ADS)

    Yan, Zhengren; Chen, Zhiyuan; Qin, Minghui; Lu, Xubing; Gao, Xingsen; Liu, Junming

    2018-02-01

    We study the spin dynamics in antiferromagnetic nanowire under an applied temperature gradient using micromagnetic simulations on a classical spin model with a uniaxial anisotropy. The entropic torque driven domain-wall motion and the Brownian motion are discussed in detail, and their competition determines the antiferromagnetic wall motion towards the hotter or colder region. Furthermore, the spin dynamics in an antiferromagnet can be well tuned by the anisotropy and the temperature gradient. Thus, this paper not only strengthens the main conclusions obtained in earlier works [Kim et al., Phys. Rev. B 92, 020402(R) (2015), 10.1103/PhysRevB.92.020402; Selzer et al., Phys. Rev. Lett. 117, 107201 (2016), 10.1103/PhysRevLett.117.107201], but more importantly gives the concrete conditions under which these conclusions apply, respectively. Our results may provide useful information on the antiferromagnetic spintronics for future experiments and storage device design.

  2. Dura covered with fibrin glue reduces adhesions in abdominal wall defects.

    PubMed

    Schier, F; Srour, N; Waldschmidt, J

    1991-12-01

    Dura can greatly facilitate the closure of abdominal wall defects. However, a main disadvantage of its use are the adhesions which develop between omentum, bowel and dura and may lead to bowel obstructions. In this study various groups of rats had either the anterior wall replaced by untreated dura or by dura covered with fibrin glue prior to implantation. Adhesions were found in 75% of sham operated rats, 100% after untreated dura implantation and 50% after the implantation of fibrin glue treated dura.

  3. The risk of volvulus in abdominal wall defects.

    PubMed

    Abdelhafeez, Abdelhafeez H; Schultz, Jessica A; Ertl, Allison; Cassidy, Laura D; Wagner, Amy J

    2015-04-01

    Congenital abdominal wall defects are associated with abnormal intestinal rotation and fixation. A Ladd's procedure is not routinely performed in these patients; it is believed intestinal fixation is provided by adhesions that develop post-repair of the defects. However, patients with omphalocele may not have adequately protective postoperative adhesions because of difference in the inflammatory state of the bowel wall and in repair strategy. The aim of this study is to describe the occurrence of midgut volvulus in patients with gastroschisis or omphalocele. A retrospective chart review was performed for all patients managed in a single institution born between 1/1/2000 and 12/31/2008 with a diagnosis of gastroschisis or omphalocele. Patient charts were reviewed through 12/31/2012 for occurrence of midgut volvulus or need for second laparotomy. Of the 206 patients identified with abdominal wall defects, 142 patients (69%) had gastroschisis and 64 patients (31%) had omphalocele. Patients' follow up ranged from 4 years to 13 years. The median gestational age was 36 weeks (26-41 weeks) and the median birth weight was 2.42 kg (0.8-4.87 kg). None of the patients with gastroschisis developed midgut volvulus, however two patients (3%) with omphalocele developed midgut volvulus. No patients with gastroschisis developed midgut volvulus. Therefore, the current practice of not routinely performing a Ladd's procedure is a safe approach during surgical repair of gastroschisis. The two cases of volvulus in patients with omphalocele may be related to less bowel fixation. It is necessary to examine current practice in regards to the need for assessing the risk of volvulus during omphalocele closure and counseling of these patients. This assessment may be achieved via routine examination of the width of the small bowel mesenteric base, whenever feasible; however, the sample size is relatively small to draw any definitive conclusions. Published by Elsevier Inc.

  4. Resterilized mesh in repair of abdominal wall defects in rats.

    PubMed

    Sucullu, Ilker; Akin, Mehmet Levhi; Yitgin, Selahattin; Filiz, Ali Ilker; Kurt, Yavuz

    2008-01-01

    A variety of negative opinions about repeated usage of relatively expensive resterilized synthetic meshes have been considered. It had been stated that resterilized polypropylene meshes inhibits fibroblastic activity, decreases proliferative activity, and increases apoptosis in human fibroblast culture, in vitro. The purpose of this study is the in vivo evaluation of the resterilized mesh repairs of abdominal hernia defects in rat models of incisional hernia by comparing primer repair and original mesh repairs. The rats (n = 22) were separated into three groups. While the abdominal defect was repaired by primary suture in the control group (CG), the defects were repaired by original mesh (OG) or resterilized mesh (RG) in mesh-repaired groups. After 21 days, the rats were evaluated for tissue tensile strengths, tissue hydroxyproline levels, tissue inflammation, fibrosis, and apoptosis. Although the tensile strengths in OG and RG were significantly higher than those of CG (p < .05 and p < .05), there was no significant difference between two groups. The tissue hydroxyproline levels in OG and RG were also higher than those of CG. The difference was not significant between the two groups. The inflammation and fibrosis indexes in OG and RG were significantly higher than those of CG (p < .0001 for both), but there was no difference between groups. While the apoptosis index in OG and RG was also higher than that of CG (p < .0001 for both), there was no significant difference between OG and RG. The usage of resterilized mesh in abdominal wall repair did not reduce the tissue tensile strength, did not affect the tissue hydroxyproline levels, did not decrease the fibrosis, and did not increase the tissue inflammation and apoptosis. In conclusion, usage of resterilized meshes in abdominal wall defects was as safe as sterilized meshes.

  5. 2017 update of the WSES guidelines for emergency repair of complicated abdominal wall hernias.

    PubMed

    Birindelli, Arianna; Sartelli, Massimo; Di Saverio, Salomone; Coccolini, Federico; Ansaloni, Luca; van Ramshorst, Gabrielle H; Campanelli, Giampiero; Khokha, Vladimir; Moore, Ernest E; Peitzman, Andrew; Velmahos, George; Moore, Frederick Alan; Leppaniemi, Ari; Burlew, Clay Cothren; Biffl, Walter L; Koike, Kaoru; Kluger, Yoram; Fraga, Gustavo P; Ordonez, Carlos A; Novello, Matteo; Agresta, Ferdinando; Sakakushev, Boris; Gerych, Igor; Wani, Imtiaz; Kelly, Michael D; Gomes, Carlos Augusto; Faro, Mario Paulo; Tarasconi, Antonio; Demetrashvili, Zaza; Lee, Jae Gil; Vettoretto, Nereo; Guercioni, Gianluca; Persiani, Roberto; Tranà, Cristian; Cui, Yunfeng; Kok, Kenneth Y Y; Ghnnam, Wagih M; Abbas, Ashraf El-Sayed; Sato, Norio; Marwah, Sanjay; Rangarajan, Muthukumaran; Ben-Ishay, Offir; Adesunkanmi, Abdul Rashid K; Lohse, Helmut Alfredo Segovia; Kenig, Jakub; Mandalà, Stefano; Coimbra, Raul; Bhangu, Aneel; Suggett, Nigel; Biondi, Antonio; Portolani, Nazario; Baiocchi, Gianluca; Kirkpatrick, Andrew W; Scibé, Rodolfo; Sugrue, Michael; Chiara, Osvaldo; Catena, Fausto

    2017-01-01

    Emergency repair of complicated abdominal wall hernias may be associated with worsen outcome and a significant rate of postoperative complications. There is no consensus on management of complicated abdominal hernias. The main matter of debate is about the use of mesh in case of intestinal resection and the type of mesh to be used. Wound infection is the most common complication encountered and represents an immense burden especially in the presence of a mesh. The recurrence rate is an important topic that influences the final outcome. A World Society of Emergency Surgery (WSES) Consensus Conference was held in Bergamo in July 2013 with the aim to define 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. In 2016, the guidelines have been revised and updated according to the most recent available literature.

  6. Tension-free repair during extensive radical surgery for cecal cancer with abdominal wall invasion and inguinal lymph node metastasis

    PubMed Central

    Xu, Kaiwu; Chen, Zhihui; Song, Xinming

    2014-01-01

    We report a case of cecal cancer with invasion of the abdominal wall and right inguinal lymph node metastasis. This patient had undergone an appendectomy 2 years previously. He underwent extensive radical right hemicolectomy with anastomosis and tension-free repair of the damaged right lower abdominal wall. The surgery progressed successfully, and the vital signs of the patient were stable (approximately 200 mL blood loss). Postoperative diagnosis revealed moderately to poorly differentiated adenocarcinoma of the cecum with invasion of the abdominal wall and metastasis of the inguinal lymph nodes (pT4bN2bM1, IV4a). The patient has remained well post-surgery. PMID:24855366

  7. Abdominal Wall Defects in Greenland 1989-2015.

    PubMed

    Bugge, Merete; Drachmann, Gitte; Kern, Peder; Budtz-Jørgensen, Esben; Eiberg, Hans; Olsen, Britta; Tommerup, Niels; Nielsen, Inge-Merete

    2017-07-03

    In the last decades, an increasing rate of gastroschisis but not of omphalocele has been reported worldwide. Greenland is the world's largest island, but 80% is covered by an ice cap, it has a small population of around 56,000 peoples (as of 2016). The occurrence of abdominal wall defects has never been investigated in Greenland. The present study is based on data retrieved from three nationwide and two local registries in the Greenlandic health care system over 27 years (1989-2015). We identified 33 infants with abdominal wall defects born in the study time period. All cases were reclassified to 28 cases of gastroschisis, four cases of omphalocele, and there was 1 infant in the indeterminate group. The point prevalence at birth for gastroschisis increased significantly from 8 to 35 (average 10.7) per 10,000 liveborn and -stillborn infants. Mothers below 20 years of age represented 23% of all cases and the prevalence for this group was 17 per 10,000 liveborn and stillborn. Perinatal mortality for infants with gastroschisis was high (18%), and 1 year survival was 71%. For omphalocele, the prevalence varied from 8 to 11 per 10,000 liveborn and stillborn infants. There was no increasing rate in the period, further highlighting an etiological difference between gastroschisis and omphalocele. This study confirms the increasing prevalence of gastroschisis in Greenland in the period from 1989 to 2015. The average was 10.7 per 10,000 liveborn and -stillborn infants and, to the best of our knowledge, this is the highest prevalence ever reported. Birth Defects Research 109:836-842, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Comparison of prosthetic materials for abdominal wall reconstruction in the presence of contamination and infection.

    PubMed Central

    Brown, G L; Richardson, J D; Malangoni, M A; Tobin, G R; Ackerman, D; Polk, H C

    1985-01-01

    Abdominal wall defects resulting from trauma, invasive infection, or hernia present a difficult problem for the surgeon. In order to study the problems associated with the prosthetic materials used for abdominal wall reconstruction, an animal model was used to simulate abdominal wall defects in the presence of peritonitis and invasive infection. One hundred guinea pigs were repaired with either polytetrafluorethylene (PTFE) or polypropylene mesh (PPM). Our experiments included intra-operative contamination with Staphylococcus aureus. We found significantly fewer organisms (p less than 0.05) adherent to the PTFE than to the PPM when antibiotics were administered after surgery, as well as when no antibiotics were given. In the presence of peritonitis, we found no real difference in numbers of intraperitoneal bacteria present whether PTFE or PPM was used. In all instances, the PTFE patches produced fewer adhesions and were more easily removed. From these experiments, it appears that PTFE may be associated with fewer problems than PPM in the presence of contamination and infection. Images FIG. 1. PMID:3159353

  9. An observational study: Effects of tenting of the abdominal wall on peak airway pressure in robotic radical prostatectomy surgery

    PubMed Central

    Kakde, Avinash Sahebarav; Wagh, Harshal D.

    2017-01-01

    Background: Robotic radical prostatectomy (RRP) is associated with various anesthetic challenges due to pneumoperitoneum and deep Trendelenburg position. Tenting of the abdominal wall done in RRP surgery causes decrease in peak airway pressure leading to better ventilation. Herein, we aimed to describe the effects of tenting of the abdominal wall on peak airway pressure in RRP surgery performed in deep Trendelenburg position. Methods: One hundred patients admitted for RRP in Kokilaben Dhirubhai Ambani Hospital of American Society of Anesthesiologists 1 and 2 physical status were included in the study. After undergoing preanesthesia work-up, patients received general anesthesia. Peak airway pressures were recorded after induction of general anesthesia, after insufflation of CO2, after giving Trendelenburg position, and after tenting of the abdominal wall with robotic arms. Results: Mean peak airway pressure recording after induction in supine position was 19.5 ± 2.3 cm of H2O, after insufflation of CO2 in supine position was 26.3 ± 2.6 cm of H2O, after giving steep head low was 34.1 ± 3.4 cm of H2O, and after tenting of the abdominal wall with robotic arms was 29.5 ± 2.5 cm of H2O. P value is highly statistically significant (P = 0.001). Conclusion: Tenting of the abdominal wall during RRP is beneficial as it decreases peak airway pressure and helps in better ventilation and thus reduces the ill effects of raised peak airway pressure and intra-abdominal pressures. PMID:28757826

  10. Giant spigelian hernia due to abdominal wall injury: a case report.

    PubMed

    Topal, Ersun; Kaya, Ekrem; Topal, Naile Bolca; Sahin, Ilker

    2007-02-01

    Spigelian hernia is a rare clinical entity. It is difficult to diagnose due to its location. In this article we report the case of a giant spigelian hernia consequent to abdominal wall injury. The neck of the hernia was 10 cm in diameter. We repaired this hernia with a polypropylene mesh.

  11. Prior Radiotherapy Does Not Affect Abdominal Wall Reconstruction Outcomes: Evidence from Propensity Score Analysis.

    PubMed

    Giordano, Salvatore; Garvey, Patrick B; Baumann, Donald P; Liu, Jun; Butler, Charles E

    2017-03-01

    Prior abdominal wall radiotherapy (XRT) adversely affects wound healing, but data are limited on how prior XRT may affect abdominal wall reconstruction (AWR) outcomes. The purpose of this study was to determine whether prior abdominal wall radiotherapy is associated with a higher incidence of complications following AWR for a hernia or oncologic resection defect. We performed a retrospective study of consecutive patients who underwent complex AWR using acellular dermal matrix (ADM) at a single center. We compared outcomes between patients who underwent prior XRT that directly involved the abdominal wall and those who did not receive XRT. Propensity score match-paired and multivariate analyses were performed. A total of 511 patients (130 [25.4 %] with prior XRT; 381 [74.6 %] without prior XRT) underwent AWR with ADM for repair of a complex hernia or oncologic resection defect. Mean follow-up was 31.4 months, mean XRT dose was 48.9 Gy, and mean time between XRT and reconstruction was 19.2 months. XRT AWR patients underwent more flap reconstructions (14.6 vs. 5.0 %, P < 0.001) but fewer component separations (61.5 vs. 71.4 %; P = 0.036) than non-XRT AWR patients. The two groups had similar rates of hernia recurrence (8.5 vs. 9.4 %; P = 0.737) and surgical site occurrence (25.4 vs. 23.4 %; P = 0.640). In the propensity score-matched subgroups, there were no differences in hernia recurrence, surgical site occurrence, and wound healing complication rates. Prior XRT does not adversely affect outcomes in AWR. However, surgeons should be aware of the higher likelihood of needing a soft tissue flap reconstruction for soft tissue replacement when performing AWR after XRT.

  12. Abdominal wall reconstruction using a combination of free tensor fasciae lata and anterolateral thigh myocutaneous flap: a prospective study in 16 patients.

    PubMed

    Lv, Yang; Cao, Dongsheng; Guo, Fangfang; Qian, Yunliang; Wang, Chen; Wang, Danru

    2015-08-01

    Reconstruction of the abdominal wall continues to be a challenging problem for plastic surgeons. Transposition of well-vascularized flap tissue is the most effective way to repair composite abdominal wall defects. We retrospectively reviewed the treatment of such patients and assessed the reconstructive technique using combination of an inlay of bioprosthetic materials and a united thigh flap. A retrospective review of patients' records in the department was carried out. In total, 16 patients who underwent immediate abdominal wall reconstruction between 2000 and 2013 were identified. Patients' health status, defect sizes, and surgical technique were obtained from medical charts. The immediate reconstruction surgery of the abdominal wall was successful in all patients. One patient with dermatofibrosarcoma protuberans experienced recurrences at the former site. One patient died because of liver metastases at 21 months after surgery. No incisional hernia or infection in this series of patients was observed. Full-thickness, giant defects of the complicated abdominal wall can be repaired successfully with relatively minor complications using this reconstructive technique. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Illustrated review of new imaging techniques in the diagnosis of abdominal wall hernias.

    PubMed

    Toms, A P; Dixon, A K; Murphy, J M; Jamieson, N V

    1999-10-01

    The assessment of abdominal wall hernias has long been a clinical skill that only occasionally required the supplementary radiological assistance of herniography. However, with the advent of cross-sectional imaging, a new range of diagnostic tools is now available to help the clinician in difficult cases. This review explores the ability of computed tomography and magnetic resonance imaging to demonstrate many of the hernias encountered in the anterior abdominal wall. Also discussed is the role of imaging techniques in the management of a variety of hernias. Cross-sectional imaging techniques are being employed with increasing frequency for the assessment of hernias. Although the anatomical detail can usually be delineated clearly, the accuracy of the various methods and their place in the clinical management of hernias has yet to be fully determined.

  14. 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. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  15. Laparoscopic-guided abdominal wall nerve blocks in the pediatric population: a novel technique with comparison to ultrasound-guided blocks and local wound infiltration alone.

    PubMed

    Landmann, Alessandra; Visoiu, Mihaela; Malek, Marcus M

    2018-03-01

    Abdominal wall nerve blocks have been gaining popularity for the treatment of perioperative pain in children. Our aim was to compare a technique of surgeon-performed, laparoscopic abdominal wall nerve blocks to anesthesia-placed, ultrasound-guided abdominal wall nerve blocks and the current standard of local wound infiltration. After institutional review board approval was obtained, a retrospective chart review was performed of pediatric patients treated at a single institution during a 2-year period. Statistics were calculated using analysis of variance with post-hoc Bonferonni t tests for pair-wise comparisons. Included in this study were 380 patients who received ultrasound-guided abdominal wall nerve blocks (n = 125), laparoscopic-guided abdominal wall nerve blocks (n = 88), and local wound infiltration (n = 117). Groups were well matched for age, sex, and weight. There was no significant difference in pain scores within the first 8 hours or narcotic usage between groups. Local wound infiltration demonstrated the shortest overall time required to perform (P < .0001). Patients who received a surgeon-performed abdominal wall nerve block demonstrated a shorter duration of hospital stay when compared to the other groups (P = .02). Our study has demonstrated that laparoscopic-guided abdominal wall nerve blocks show similar efficacy to ultrasound-guided nerve blocks performed by pain management physicians without increasing time in the operating room. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Komine, Takashi, E-mail: komine@mx.ibaraki.ac.jp; Aono, Tomosuke

    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.

  17. Linear motion feed through with thin wall rubber sealing element

    NASA Astrophysics Data System (ADS)

    Mikhailov, V. P.; Deulin, E. A.

    2017-07-01

    The patented linear motion feedthrough is based on elastic thin rubber walls usage being reinforced with analeptic string fixed in the middle part of the walls. The pneumatic or hydro actuators create linear movement of stock. The length of this movement is two times more the rubber wall length. This flexible wall is a sealing element of feedthrough. The main advantage of device is negligible resistance force that is less then mentioned one in sealing bellows that leads to positioning error decreasing. Nevertheless, the thin wall rubber sealing element (TRE) of the feedthrough is the main unreliable element that was the reason of this element longevity research. The theory and experimental results help to create equation for TRE longevity calculation under vacuum or extra high pressure difference action. The equation was used for TRE longevity determination for hydraulic or vacuum equipment realization also as it helps for gas flow being leaking through the cracks in thin walls of rubber sealing element of linear motion feedthrough calculation.

  18. Abdominal wall reinforcement: biologic vs. degradable synthetic devices.

    PubMed

    Gruber-Blum, S; Brand, J; Keibl, C; Fortelny, R H; Redl, H; Mayer, F; Petter-Puchner, A H

    2017-04-01

    New biodegradable synthetic and biologic hernia implants have been promoted for rapid integration and tissue reinforcement in challenging repairs, e.g. at the hiatus or in contaminated wound fields. Interestingly, experimental data to support or falsify this assumption is scarce. Synthetic (BioA ® ) and biologic implants (porcine and bovine collagen matrices Strattice ® and Veritas ® ) have been tested in experimental onlay hernia repair in rats in observation periods of 30 and 60 days. The key outcome parameters were mesh integration and reinforcement of the tissue at the implant site over sutured and sealed defects as well as comparison to native abdominal wall. Macroscopic assessment, biomechanical analysis and histology with haematoxylin/eosin staining, collagen staining and van Willebrand factor staining for detection of neovascularization were performed. BioA ® was well integrated. Although the matrices were already fragmented at 60 days follow-up, hernia sites treated with synthetic scaffolds showed a significantly enhanced tissue deflection and resistance to burst force when compared to the native abdominal wall. In porcine and bovine matrices, tissue integration and shrinkage were significantly inferior to BioA ® . Histology revealed a lack of fibroblast ingrowth through mesh interstices in biologic samples, whereas BioA ® was tightly connected to the underlying tissue by reticular collagen fibres. Strattice ® and Veritas ® yielded reduced tissue integration and significant shrinkage, prohibiting further biomechanical tests. The synthetic BioA ® provides little inherent strength but reticular collagen remodelling led to an augmentation of the scar due to significantly higher burst force resistance in comparison to native tissue.

  19. Evaluation of segmental left ventricular wall motion by equilibrium gated radionuclide ventriculography.

    PubMed

    Van Nostrand, D; Janowitz, W R; Holmes, D R; Cohen, H A

    1979-01-01

    The ability of equilibrium gated radionuclide ventriculography to detect segmental left ventricular (LV) wall motion abnormalities was determined in 26 patients undergoing cardiac catheterization. Multiple gated studies obtained in 30 degrees right anterior oblique and 45 degrees left anterior oblique projections, played back in a movie format, were compared to the corresponding LV ventriculograms. The LV wall in the two projections was divided into eight segments. Each segment was graded as normal, hypokinetic, akinetic, dyskinetic, or indeterminate. Thirteen percent of the segments in the gated images were indeterminate; 24 out of 27 of these were proximal or distal inferior wall segments. There was exact agreement in 86% of the remaining segments. The sensitivity of the radionuclide technique for detecting normal versus any abnormal wall motion was 71%, with a specificity of 99%. Equilibrium gated ventriculography is an excellent noninvasive technique for evaluating segmental LV wall motion. It is least reliable in assessing the proximal inferior wall and interventricular septum.

  20. Rectus sheath block: successful use in the chronic pain management of pediatric abdominal wall pain.

    PubMed

    Skinner, Adam V; Lauder, Gillian R

    2007-12-01

    Seven pediatric patients (aged 11-16 years) with chronic abdominal wall pain are presented who gained significant relief from a rectus sheath block (RSB). We describe the case histories and review the relevant literature for this technique. The etiology of the abdominal wall pain was considered to be abdominal cutaneous nerve entrapment, iatrogenic peripheral nerve injury, myofascial pain syndrome or was unknown. All patients showed significant initial improvement in pain and quality of life. Three patients required only the RSB to enable them to be pain-free and return to normal schooling and physical activities. Two children received complete relief for more than 1 year. In the majority of cases, the procedure was carried out under general anesthesia as a daycase procedure. Local anesthetic and steroids were used. This is the first report of the successful use of this technique in the chronic pain management setting in children.

  1. Mechanical behavior of surgical meshes for abdominal wall repair: In vivo versus biaxial characterization.

    PubMed

    Simón-Allué, R; Ortillés, A; Calvo, B

    2018-06-01

    Despite the widespread use of synthetic meshes in the surgical treatment of the hernia pathology, the election criteria of a suitable mesh for specific patient continues to be uncertain. Thus, in this work, we propose a methodology to determine in advance potential disadvantages on the use of certain meshes based on the patient-specific abdominal geometry and the mechanical features of the certain meshes. To that purpose, we have first characterized the mechanical behavior of four synthetic meshes through biaxial tests. Secondly, two of these meshes were implanted in several New Zealand rabbits with a total defect previously created on the center of the abdominal wall. After the surgical procedure, specimen were subjected to in vivo pneumoperitoneum tests to determine the immediate post-surgical response of those meshes after implanted in a healthy specimen. Experimental performance was recorded by a stereo rig with the aim of obtaining quantitative information about the pressure-displacement relation of the abdominal wall. Finally, following the procedure presented in prior works (Simón-Allué et al., 2015, 2017), a finite element model was reconstructed from the experimental measurements and tests were computationally reproduced for the healthy and herniated cases. Simulations were compared and validated with the in vivo behavior and results were given along the abdominal wall in terms of displacements, stresses and strain. Mechanical characterization of the meshes revealed Surgipro TM as the most rigid implant and Neomesh SuperSoft® as the softer, while other two meshes (Neomesh Soft®, Neopore®) remained in between. These two meshes were employed in the experimental study and resulted in similar effect in the abdominal wall cavity and both were close to the healthy case. Simulations confirmed this result while showed potential objections in the case of the other two meshes, due to high values in stresses or elongation that may led to discomfort in real

  2. Primary fascial closure with biologic mesh reinforcement results in lesser complication and recurrence rates than bridged biologic mesh repair for abdominal wall reconstruction: A propensity score analysis.

    PubMed

    Giordano, Salvatore; Garvey, Patrick B; Baumann, Donald P; Liu, Jun; Butler, Charles E

    2017-02-01

    Previous studies suggest that bridged mesh repair for abdominal wall reconstruction may result in worse outcomes than mesh-reinforced, primary fascial closure, particularly when acellular dermal matrix is used. We compared our outcomes of bridged versus reinforced repair using ADM in abdominal wall reconstruction procedures. This retrospective study included 535 consecutive patients at our cancer center who underwent abdominal wall reconstruction either for an incisional hernia or for abdominal wall defects left after excision of malignancies involving the abdominal wall with underlay mesh. A total of 484 (90%) patients underwent mesh-reinforced abdominal wall reconstruction and 51 (10%) underwent bridged repair abdominal wall reconstruction. Acellular dermal matrix was used, respectively, in 98% of bridged and 96% of reinforced repairs. We compared outcomes between these 2 groups using propensity score analysis for risk-adjustment in multivariate analysis and for 1-to-1 matching. Bridged repairs had a greater hernia recurrence rate (33.3% vs 6.2%, P < .001), a greater overall complication rate (59% vs 30%, P = .001), and worse freedom from hernia recurrence (log-rank P <.001) than reinforced repairs. Bridged repairs also had a greater rate of wound dehiscence (26% vs 14%, P = .034) and mesh exposure (10% vs 1%, P = .003) than mesh-reinforced abdominal wall reconstruction. When the treatment method was adjusted for propensity score in the propensity-score-matched pairs (n = 100), we found that the rates of hernia recurrence (32% vs 6%, P = .002), overall complications (32% vs 6%, P = .002), and freedom from hernia recurrence (68% vs 32%, P = .001) rates were worse after bridged repair. We did not observe differences in wound healing and mesh complications between the 2 groups. In our population of primarily cancer patients at MD Anderson Cancer Center bridged repair for abdominal wall reconstruction is associated with worse outcomes than mesh

  3. Minilaparotomy with a gasless laparoscopic-assisted procedure by abdominal wall lifting for ileorectal anastomosis in patients with slow transit constipation.

    PubMed

    Tomita, Ryouichi; Fujisak, Shigeru

    2009-01-01

    Total colectomy with ileorectal anastomosis (IRA) is the most widely adopted procedure. The aim of this study was to introduce a minimally invasive procedure, i.e., minilaparotomy with laparoscopic-assisted procedure, by abdominal wall lifting for IRA in patients with slow transit constipation (STC). Six STC patients (6 women, aged 40-69 years, mean age 56.3 years) underwent minilaparotomy with gasless laparoscopic-assisted approach by abdominal wall lifting for IRA. The present procedure involved a 7-cm lower abdominal median incision made at the beginning of the operation. 12 mm ports were also placed in the right and left upper abdominal quadrant positions. The upper abdominal wall was lifted by a subcutaneous Kirshner wire. The small wound was pulled upward and/or laterally by retractors (abdominal lifting) and conventional surgical instruments were used through the wound. Occasionally laparoscopic assistance was employed. The terminal ileum with total colon was brought out through the small wound and transected, approximately 5 cm from the ileocecal valve. The colon was also resected at the level of promontrium. Then, IRA was performed in the instruments. The total surgical time was 197.7 +/- 33.9 min and the mean estimated blood loss was 176.8 +/- 42.2 ml. There was no surgical mortality. Post-operative hospitalization was 8.1 +/- 2.1 days. Six months after surgery, they defecated 1.8 +/- 2.1 times daily, have no abdominal distension, pain, and incontinence. The patients also take no laxatives. All subjects were satisfied with this procedure. Minilaparotomy with gasless laparoscopic-assisted IRA by abdominal wall lifting could be a safe and efficient technique in the treatment of STC.

  4. Left hepatic lobe herniation through an incisional anterior abdominal wall hernia and right adrenal myelolipoma: a case report and review of the literature.

    PubMed

    Nuño-Guzmán, Carlos M; Arróniz-Jáuregui, José; Espejo, Ismael; Valle-González, Jesús; Butus, Hernán; Molina-Romo, Alejandro; Orranti-Ortega, Rodrigo I

    2012-01-10

    Herniation of the liver through an anterior abdominal wall hernia defect is rare. To the best of our knowledge, only three cases have been described in the literature. A 70-year-old Mexican woman presented with a one-week history of right upper quadrant abdominal pain, nausea, vomiting, and jaundice to our Department of General Surgery. Her medical history included an open cholecystectomy from 20 years earlier and excessive weight. She presented with jaundice, abdominal distension with a midline surgical scar, right upper quadrant tenderness, and a large midline abdominal wall defect with dullness upon percussion and protrusion of a large, tender, and firm mass. The results of laboratory tests were suggestive of cholestasis. Ultrasound revealed choledocholithiasis. A computed tomography scan showed a protrusion of the left hepatic lobe through the anterior abdominal wall defect and a well-defined, soft tissue density lesion in the right adrenal topography. An endoscopic common bile duct stone extraction was unsuccessful. During surgery, the right adrenal tumor was resected first. The hernia was approached through a median supraumbilical incision; the totality of the left lobe was protruding through the abdominal wall defect, and once the lobe was reduced to its normal position, a common bile duct surgical exploration with multiple stone extraction was performed. Finally, the abdominal wall was reconstructed. Histopathology revealed an adrenal myelolipoma. Six months after the operation, our patient remains in good health. The case of liver herniation through an incisional anterior abdominal wall hernia in this report represents, to the best of our knowledge, the fourth such case reported in the literature. The rarity of this medical entity makes it almost impossible to specifically describe predisposing risk factors for liver herniation. Obesity, the right adrenal myelolipoma mass effect, and the previous abdominal surgery are likely to have contributed to

  5. Gasless laparoscopic surgery plus abdominal wall lifting for giant hiatal hernia-our single-center experience.

    PubMed

    Yu, Jiang-Hong; Wu, Ji-Xiang; Yu, Lei; Li, Jian-Ye

    2016-12-01

    Giant hiatal hernia (GHH) comprises 5% of hiatal hernia and is associated with significant complications. The traditional operative procedure, no matter transthoracic or transabdomen repair of giant hiatal hernia, is characteristic of more invasion and more complications. Although laparoscopic repair as a minimally invasive surgery is accepted, a part of patients can not tolerate pneumoperitoneum because of combination with cardiopulmonary diseases or severe posterior mediastinal and neck emphesema during operation. The aim of this article was to analyze our experience in gasless laparoscopic repair with abdominal wall lifting to treat the giant hiatal hernia. We performed a retrospective review of patients undergoing gasless laparoscopic repair of GHH with abdominal wall lifting from 2012 to 2015 at our institution. The GHH was defined as greater than one-third of the stomach in the chest. Gasless laparoscopic repair of GHH with abdominal wall lifting was attempted in 27 patients. Mean age was 67 years. The results showed that there were no conversions to open surgery and no intraoperative deaths. The mean duration of operation was 100 min (range: 90-130 min). One-side pleura was injured in 4 cases (14.8%). The mean postoperative length of stay was 4 days (range: 3-7 days). Median follow- up was 26 months (range: 6-38 months). Transient dysphagia for solid food occurred in three patients (11.1%), and this symptom disappeared within three months. There was one patient with recurrent hiatal hernia who was reoperated on. Two patients still complained of heartburn three months after surgery. Neither reoperation nor endoscopic treatment due to signs of postoperative esophageal stenosis was required in any patient. Totally, satisfactory outcome was reported in 88.9% patients. It was concluded that the gasless laparoscopic approach with abdominal wall lifting to the repair of GHH is feasible, safe, and effective for the patients who cannot tolerate the pneumoperitoneum.

  6. Segmentation of arterial vessel wall motion to sub-pixel resolution using M-mode ultrasound.

    PubMed

    Fancourt, Craig; Azer, Karim; Ramcharan, Sharmilee L; Bunzel, Michelle; Cambell, Barry R; Sachs, Jeffrey R; Walker, Matthew

    2008-01-01

    We describe a method for segmenting arterial vessel wall motion to sub-pixel resolution, using the returns from M-mode ultrasound. The technique involves measuring the spatial offset between all pairs of scans from their cross-correlation, converting the spatial offsets to relative wall motion through a global optimization, and finally translating from relative to absolute wall motion by interpolation over the M-mode image. The resulting detailed wall distension waveform has the potential to enhance existing vascular biomarkers, such as strain and compliance, as well as enable new ones.

  7. Aggregatibacter actinomycetemcomitans pneumonia with chest and abdominal wall involvement.

    PubMed

    Storms, Iris; van den Brand, Marre; Schneeberger, Peter; van 't Hullenaar, Nico

    2017-04-21

    A 54-year-old man presented with a productive cough, chest pain, fever and weight loss. Initial analysis revealed a palpable chest wall mass and consolidation in the left lower lobe and pleural abnormalities on imaging. At that point no infectious cause or malignancy was identified. Microbiological analysis of a needle biopsy from a newly developed abdominal wall mass revealed growth of Aggregatibacter actinomycetemcomitans The patient was successfully treated with antibiotic therapy for 1 year. Aggregatibacter actinomycetemcomitans is a Gram-negative coccobacillus and is part of the normal oral flora. It is capable of causing infections in humans including periodontitis, soft tissue abscesses and systemic invasive infections, most commonly endocarditis. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. Real-time method for motion-compensated MR thermometry and MRgHIFU treatment in abdominal organs.

    PubMed

    Celicanin, Zarko; Auboiroux, Vincent; Bieri, Oliver; Petrusca, Lorena; Santini, Francesco; Viallon, Magalie; Scheffler, Klaus; Salomir, Rares

    2014-10-01

    Magnetic resonance-guided high-intensity focused ultrasound is considered to be a promising treatment for localized cancer in abdominal organs such as liver, pancreas, or kidney. Abdominal motion, anatomical arrangement, and required sustained sonication are the main challenges. MR acquisition consisted of thermometry performed with segmented gradient-recalled echo echo-planar imaging, and a segment-based one-dimensional MR navigator parallel to the main axis of motion to track the organ motion. This tracking information was used in real-time for: (i) prospective motion correction of MR thermometry and (ii) HIFU focal point position lock-on target. Ex vivo experiments were performed on a sheep liver and a turkey pectoral muscle using a motion demonstrator, while in vivo experiments were conducted on two sheep liver. Prospective motion correction of MR thermometry yielded good signal-to-noise ratio (range, 25 to 35) and low geometric distortion due to the use of segmented EPI. HIFU focal point lock-on target yielded isotropic in-plane thermal build-up. The feasibility of in vivo intercostal liver treatment was demonstrated in sheep. The presented method demonstrated in moving phantoms and breathing sheep accurate motion-compensated MR thermometry and precise HIFU focal point lock-on target using only real-time pencil-beam navigator tracking information, making it applicable without any pretreatment data acquisition or organ motion modeling. Copyright © 2013 Wiley Periodicals, Inc.

  9. The impact of personalized probabilistic wall thickness models on peak wall stress in abdominal aortic aneurysms.

    PubMed

    Biehler, J; Wall, W A

    2018-02-01

    If computational models are ever to be used in high-stakes decision making in clinical practice, the use of personalized models and predictive simulation techniques is a must. This entails rigorous quantification of uncertainties as well as harnessing available patient-specific data to the greatest extent possible. Although researchers are beginning to realize that taking uncertainty in model input parameters into account is a necessity, the predominantly used probabilistic description for these uncertain parameters is based on elementary random variable models. In this work, we set out for a comparison of different probabilistic models for uncertain input parameters using the example of an uncertain wall thickness in finite element models of abdominal aortic aneurysms. We provide the first comparison between a random variable and a random field model for the aortic wall and investigate the impact on the probability distribution of the computed peak wall stress. Moreover, we show that the uncertainty about the prevailing peak wall stress can be reduced if noninvasively available, patient-specific data are harnessed for the construction of the probabilistic wall thickness model. Copyright © 2017 John Wiley & Sons, Ltd.

  10. The Relationship Between Surface Curvature and Abdominal Aortic Aneurysm Wall Stress.

    PubMed

    de Galarreta, Sergio Ruiz; Cazón, Aitor; Antón, Raúl; Finol, Ender A

    2017-08-01

    The maximum diameter (MD) criterion is the most important factor when predicting risk of rupture of abdominal aortic aneurysms (AAAs). An elevated wall stress has also been linked to a high risk of aneurysm rupture, yet is an uncommon clinical practice to compute AAA wall stress. The purpose of this study is to assess whether other characteristics of the AAA geometry are statistically correlated with wall stress. Using in-house segmentation and meshing algorithms, 30 patient-specific AAA models were generated for finite element analysis (FEA). These models were subsequently used to estimate wall stress and maximum diameter and to evaluate the spatial distributions of wall thickness, cross-sectional diameter, mean curvature, and Gaussian curvature. Data analysis consisted of statistical correlations of the aforementioned geometry metrics with wall stress for the 30 AAA inner and outer wall surfaces. In addition, a linear regression analysis was performed with all the AAA wall surfaces to quantify the relationship of the geometric indices with wall stress. These analyses indicated that while all the geometry metrics have statistically significant correlations with wall stress, the local mean curvature (LMC) exhibits the highest average Pearson's correlation coefficient for both inner and outer wall surfaces. The linear regression analysis revealed coefficients of determination for the outer and inner wall surfaces of 0.712 and 0.516, respectively, with LMC having the largest effect on the linear regression equation with wall stress. This work underscores the importance of evaluating AAA mean wall curvature as a potential surrogate for wall stress.

  11. The effect of abdominal wall morphology on ultrasonic pulse distortion. Part II. Simulations.

    PubMed

    Mast, T D; Hinkelman, L M; Orr, M J; Waag, R C

    1998-12-01

    Wavefront propagation through the abdominal wall was simulated using a finite-difference time-domain implementation of the linearized wave propagation equations for a lossless, inhomogeneous, two-dimensional fluid as well as a simplified straight-ray model for a two-dimensional absorbing medium. Scanned images of six human abdominal wall cross sections provided the data for the propagation media in the simulations. The images were mapped into regions of fat, muscle, and connective tissue, each of which was assigned uniform sound speed, density, and absorption values. Propagation was simulated through each whole specimen as well as through each fat layer and muscle layer individually. Wavefronts computed by the finite-difference method contained arrival time, energy level, and wave shape distortion similar to that in measurements. Straight-ray simulations produced arrival time fluctuations similar to measurements but produced much smaller energy level fluctuations. These simulations confirm that both fat and muscle produce significant wavefront distortion and that distortion produced by fat sections differs from that produced by muscle sections. Spatial correlation of distortion with tissue composition suggests that most major arrival time fluctuations are caused by propagation through large-scale inhomogeneities such as fatty regions within muscle layers, while most amplitude and waveform variations are the result of scattering from smaller inhomogeneities such as septa within the subcutaneous fat. Additional finite-difference simulations performed using uniform-layer models of the abdominal wall indicate that wavefront distortion is primarily caused by tissue structures and inhomogeneities rather than by refraction at layer interfaces or by variations in layer thicknesses.

  12. Laparoscopic-assisted management of traumatic abdominal wall hernias in children: case series and a review of the literature.

    PubMed

    Talutis, Stephanie D; Muensterer, Oliver J; Pandya, Samir; McBride, Whitney; Stringel, Gustavo

    2015-03-01

    Traumatic abdominal wall hernia (TAWH) is defined as herniation through a disrupted portion of musculature/fascia without skin penetration or history of prior hernia. In children, TAWH is a rare injury. The objectives of this study were to report our experience with different management strategies of TAWH in children and to determine the utility of laparoscopy. A retrospective chart review of all children treated by pediatric surgery at our institution for TAWH in a 5year interval was performed. Data were collected on mechanism of injury, initial patient presentation, surgical management, and outcomes. We present 5 cases of traumatic abdominal wall hernia; 3 were managed using laparoscopic assistance. One patient was managed nonoperatively. All patients recovered without complications and were asymptomatic on follow up. Traumatic abdominal wall hernias require a high index of suspicion in the cases of blunt abdominal trauma. Laparoscopy is useful mainly as a diagnostic modality, both to evaluate the hernia and associated injuries to intraabdominal structures. Its use may facilitate repair through a smaller incision. Conservative management of TAWH may be appropriate in select cases where there is a low risk of bowel strangulation. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. 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.

  14. 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…

  15. Recommendations for reporting outcome results in abdominal wall repair: results of a Consensus meeting in Palermo, Italy, 28-30 June 2012.

    PubMed

    Muysoms, F E; Deerenberg, E B; Peeters, E; Agresta, F; Berrevoet, F; Campanelli, G; Ceelen, W; Champault, G G; Corcione, F; Cuccurullo, D; DeBeaux, A C; Dietz, U A; Fitzgibbons, R J; Gillion, J F; Hilgers, R-D; Jeekel, J; Kyle-Leinhase, I; Köckerling, F; Mandala, V; Montgomery, A; Morales-Conde, S; Simmermacher, R K J; Schumpelick, V; Smietański, M; Walgenbach, M; Miserez, M

    2013-08-01

    The literature dealing with abdominal wall surgery is often flawed due to lack of adherence to accepted reporting standards and statistical methodology. The EuraHS Working Group (European Registry of Abdominal Wall Hernias) organised a consensus meeting of surgical experts and researchers with an interest in abdominal wall surgery, including a statistician, the editors of the journal Hernia and scientists experienced in meta-analysis. Detailed discussions took place to identify the basic ground rules necessary to improve the quality of research reports related to abdominal wall reconstruction. A list of recommendations was formulated including more general issues on the scientific methodology and statistical approach. Standards and statements are available, each depending on the type of study that is being reported: the CONSORT statement for the Randomised Controlled Trials, the TREND statement for non randomised interventional studies, the STROBE statement for observational studies, the STARLITE statement for literature searches, the MOOSE statement for metaanalyses of observational studies and the PRISMA statement for systematic reviews and meta-analyses. A number of recommendations were made, including the use of previously published standard definitions and classifications relating to hernia variables and treatment; the use of the validated Clavien-Dindo classification to report complications in hernia surgery; the use of "time-to-event analysis" to report data on "freedom-of-recurrence" rather than the use of recurrence rates, because it is more sensitive and accounts for the patients that are lost to follow-up compared with other reporting methods. A set of recommendations for reporting outcome results of abdominal wall surgery was formulated as guidance for researchers. It is anticipated that the use of these recommendations will increase the quality and meaning of abdominal wall surgery research.

  16. 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.

  17. Motion and ranging sensor system for through-the-wall surveillance system

    NASA Astrophysics Data System (ADS)

    Black, Jeffrey D.

    2002-08-01

    A portable Through-the-Wall Surveillance System is being developed for law enforcement, counter-terrorism, and military use. The Motion and Ranging Sensor is a radar that operates in a frequency band that allows for surveillance penetration of most non-metallic walls. Changes in the sensed radar returns are analyzed to detect the human motion that would typically be present during a hostage or barricaded suspect scenario. The system consists of a Sensor Unit, a handheld Remote Display Unit, and an optional laptop computer Command Display Console. All units are battery powered and a wireless link provides command and data communication between units. The Sensor Unit is deployed close to the wall or door through which the surveillance is to occur. After deploying the sensor the operator may move freely as required by the scenario. Up to five Sensor Units may be deployed at a single location. A software upgrade to the Command Display Console is also being developed. This software upgrade will combine the motion detected by multiple Sensor Units and determine and track the location of detected motion in two dimensions.

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

    PubMed Central

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

    2015-01-01

    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

  19. 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.

  20. A novel diagnostic aid for intra-abdominal adhesion detection in cine-MR imaging: Pilot study and initial diagnostic impressions.

    PubMed

    Randall, David; Joosten, Frank; ten Broek, Richard; Gillott, Richard; Bardhan, Karna Dev; Strik, Chema; Prins, Wiesje; van Goor, Harry; Fenner, John

    2017-07-14

    A non-invasive diagnostic technique for abdominal adhesions is not currently available. Capture of abdominal motion due to respiration in cine-MRI has shown promise, but is difficult to interpret. This article explores the value of a complimentary diagnostic aid to facilitate the non-invasive detection of abdominal adhesions using cine-MRI. An image processing technique was developed to quantify the amount of sliding that occurs between the organs of the abdomen and the abdominal wall in sagittal cine-MRI slices. The technique produces a 'sheargram' which depicts the amount of sliding which has occurred over 1-3 respiratory cycles. A retrospective cohort of 52 patients, scanned for suspected adhesions, made 281 cine-MRI sagittal slices available for processing. The resulting sheargrams were reported by two operators and compared to expert clinical judgement of the cine-MRI scans. The sheargram matched clinical judgement in 84% of all sagittal slices and 93-96% of positive adhesions were identified on the sheargram. The sheargram displayed a slight skew towards sensitivity over specificity, with a high positive adhesion detection rate but at the expense of false positives. Good correlation between sheargram and absence/presence of inferred adhesions indicates quantification of sliding motion has potential to aid adhesion detection in cine-MRI. Advances in Knowledge: This is the first attempt to clinically evaluate a novel image processing technique quantifying the sliding motion of the abdominal contents against the abdominal wall. The results of this pilot study reveal its potential as a diagnostic aid for detection of abdominal adhesions.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bossi, Alberto; De Wever, Ivo; Van Limbergen, Erik

    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 2more » 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.« less

  2. Pilot study on objective measurement of abdominal wall strength in patients with ventral incisional hernia.

    PubMed

    Parker, Michael; Goldberg, Ross F; Dinkins, Maryane M; Asbun, Horacio J; Daniel Smith, C; Preissler, Susanne; Bowers, Steven P

    2011-11-01

    Outcomes after ventral incisional hernia (VIH) repair are measured by recurrence rate and subjective measures. No objective metrics evaluate functional outcomes after abdominal wall reconstruction. This study aimed to develop testing of abdominal wall strength (AWS) that could be validated as a useful metric. Data were prospectively collected during 9 months from 35 patients. A total of 10 patients were evaluated before and after VIH repair, for a total of 45 encounters. The patients were tested simultaneously or in succession by two of three examiners. Data were collected for three tests: double leg lowering (DLL), trunk raising (TR), and supine reaching (SR). Raw data were compared and tested for validity, and continuous data were transformed to categorical data. Agreement was measured using the intraclass correlation coefficient (ICC) for DLL and using kappa for the ordinal measures. Simultaneous testing yielded the following interobserver reliability: DLL (0.96 and 0.87), TR (1.00 and 0.95), and SR (0.76). Reproducibility was assessed by consecutive tests, with correlation as follows: DLL (0.81), TR (0.81), and RCH (0.21). Due to poor interobserver reliability for the SR test compared with the DLL and TR tests, the SR test was excluded from calculation of an overall score. Based on raw data distribution from the DLL and TR tests, the DLL data were categorized into 10º increments, allowing construction of a 10-point score. The median AWS score was 5 (interquartile range [IQR], 4-7), and there was agreement within 1 point for 42 of the 45 encounters (93%). The findings from this study demonstrate that the 10-point AWS score may measure AWS in an accurate and reproducible fashion, with potential for objective description of abdominal wall function of VIH patients. This score may help to identify patients suited for abdominal wall reconstruction while measuring progress after VIH repair. Further longitudinal outcomes studies are needed.

  3. Wall shear stress estimation in the aorta: Impact of wall motion, spatiotemporal resolution, and phase noise.

    PubMed

    Zimmermann, Judith; Demedts, Daniel; Mirzaee, Hanieh; Ewert, Peter; Stern, Heiko; Meierhofer, Christian; Menze, Bjoern; Hennemuth, Anja

    2018-04-01

    Wall shear stress (WSS) presents an important parameter for assessing blood flow characteristics and evaluating flow-mediated lesions in the aorta. To investigate the robustness of WSS and oscillatory shear index (OSI) estimation based on 4D flow MRI against vessel wall motion, spatiotemporal resolution, and velocity encoding (VENC). Simulated and prospective. Synthetic 4D flow MRI data of the aorta, simulated using the Lattice-Boltzmann method; in vivo 4D flow MRI data of the aorta from healthy volunteers (n = 11) and patients with congenital heart defects (n = 17). 1.5T; 4D flow MRI with PEAK-GRAPPA acceleration and prospective electrocardiogram triggering. Predicated upon 3D cubic B-splines interpolation of the image velocity field, WSS was estimated in mid-systole, early-diastole, and late-diastole and OSI was derived. We assessed the impact of spatiotemporal resolution and phase noise, and compared results based on tracked-using deformable registration-and static vessel wall location. Bland-Altman analysis to assess WSS/OSI differences; Hausdorff distance (HD) to assess wall motion; and Pearson's correlation coefficient (PCC) to assess correlation of HD with WSS. Synthetic data results show systematic over-/underestimation of WSS when different spatial resolution (mean ± 1.96 SD up to -0.24 ± 0.40 N/m 2 and 0.5 ± 1.38 N/m 2 for 8-fold and 27-fold voxel size, respectively) and VENC-depending phase noise (mean ± 1.96 SD up to 0.31 ± 0.12 N/m 2 and 0.94 ± 0.28 N/m 2 for 2-fold and 4-fold VENC increase, respectively) are given. Neglecting wall motion when defining the vessel wall perturbs WSS estimates to a considerable extent (1.96 SD up to 1.21 N/m 2 ) without systematic over-/underestimation (Bland-Altman mean range -0.06 to 0.05). In addition to sufficient spatial resolution and velocity to noise ratio, accurate tracking of the vessel wall is essential for reliable image-based WSS estimation and should not be

  4. [Case report: Rapidly growing abdominal wall giant desmoid tumour during pregnancy].

    PubMed

    Palacios-Zertuche, Jorge Tadeo; Cardona-Huerta, Servando; Juárez-García, María Luisa; Valdés-Flores, Everardo; Muñoz-Maldonado, Gerardo Enrique

    Desmoid tumours are one of the rarest tumours worldwide, with an estimated yearly incidence of 2-4 new cases per million people. They are soft tissue monoclonal neoplasms that originate from mesenchymal stem cells. It seems that the hormonal and immunological changes occurring during pregnancy may play a role in the severity and course of the disease. The case is presented on 28-year-old female in her fifth week of gestation, in whom an abdominal wall tumour was found attached to left adnexa and uterus while performing a prenatal ultrasound. The patient was followed up under clinical and ultrasonographic surveillance. When she presented with abnormal uterine activity at 38.2 weeks of gestation, she was admitted and obstetrics decided to perform a caesarean section. Tumour biopsy was taken during the procedure. Histopathology reported a desmoid fibromatosis. A contrast enhanced abdominal computed tomography scan was performed, showing a tumour of 26×20.5×18cm, with well-defined borders in contact with the uterus, left adnexa, bladder and abdominal wall, with no evidence of infiltration to adjacent structures. A laparotomy, with tumour resection, hysterectomy and left salpingo-oophorectomy, components separation techniques, polypropylene mesh insertion, and drainage was performed. The final histopathology report was desmoid fibromatosis. There is no evidence of recurrence after 6 months follow-up. Desmoid tumours are locally aggressive and surgical resection with clear margins is the basis for the treatment of this disease, using radiotherapy, chemotherapy and hormone therapy as an adjunct in the treatment. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  5. Functional electrical stimulation to the abdominal wall muscles synchronized with the expiratory flow does not induce muscle fatigue.

    PubMed

    Okuno, Yukako; Takahashi, Ryoichi; Sewa, Yoko; Ohse, Hirotaka; Imura, Shigeyuki; Tomita, Kazuhide

    2017-03-01

    [Purpose] Continuous electrical stimulation of abdominal wall muscles is known to induce mild muscle fatigue. However, it is not clear whether this is also true for functional electrical stimulation delivered only during the expiratory phase of breathing. This study aimed to examine whether or not intermittent electrical stimulation delivered to abdominal wall muscles induces muscle fatigue. [Subjects and Methods] The subjects were nine healthy adults. Abdominal electrical stimulation was applied for 1.5 seconds from the start of expiration and then turned off during inspiration. The electrodes were attached to both sides of the abdomen at the lower margin of the 12th rib. Abdominal electrical stimulation was delivered for 15 minutes with the subject in a seated position. Expiratory flow was measured during stimulus. Trunk flexor torque and electromyography activity were measured to evaluate abdominal muscle fatigue. [Results] The mean stimulation on/off ratio was 1:2.3. The declining rate of abdominal muscle torque was 61.1 ± 19.1% before stimulus and 56.5 ± 20.9% after stimulus, not significantly different. The declining rate of mean power frequency was 47.8 ± 11.7% before stimulus and 47.9 ± 10.2% after stimulus, not significantly different. [Conclusion] It was found that intermittent electrical stimulation to abdominal muscles synchronized with the expiratory would not induce muscle fatigue.

  6. Desmoid Fibromatosis of the Abdominal Wall: Surgical Resection and Reconstruction with Biological Matrix Egis®

    PubMed Central

    Tropea, Saveria; Mocellin, Simone; Stramare, Roberto; Bonavina, Maria Giuseppina; Rossi, Carlo Riccardo; Rastrelli, Marco

    2017-01-01

    Desmoid tumor is a rare monoclonal fibroblast proliferation that is regarded as benign. The clinical management of desmoid tumors is very complex and requires a multidisciplinary approach because of the unpredictable disease course. For those cases localized in the anterior abdominal wall, symptomatic and unresponsive to medical treatment, radical resection and reconstruction with a prosthetic device are indicated. We present here a case of desmoid fibromatosis of the left anterolateral abdominal wall with a marked increase of the mass that required a large excision followed by reconstruction with biological matrix. The fact that it can be incorporated in patient tissue without a fibrotic response and that it can resist future infections, together with a very competetive price, made the new collagen matrix Egis® our first choice. PMID:28413398

  7. Correspondence: Laparoscopic repair of abdominal wall hernia--"How I do it"--synopsis of a seemingly straightforward technique.

    PubMed

    Berney, Christophe R

    2015-08-19

    Abdominal wall hernia repairs are commonly performed worldwide in general surgery. There is still no agreed consensus on the optimal surgical approach. Since the turn of the twenty-first century, minimally invasive techniques have gained in popularity as they combine the advantages of limited abdominal wall dissection, reduced post-operative pain and risk of complications, and shorter hospital stay. Although the added cost incurred by using sophisticated laparoscopic instruments may be quite substantial, it is precisely counterbalanced by an improved morbidity rate, faster discharge home and time to return to work. Laparoscopic abdominal wall hernia repair is often challenging, as it requires good anatomical knowledge, eye-hand coordination and diversified laparoscopic skills. The objective of this article is not to present another set of personal data and to compare it with already published results on this matter, but simply to offer comprehensive guidelines on the practical aspects of this relatively new technique. Some of these steps have already been discussed but most of the time in a scattered way in the surgical literature, while others are the fruit of a personal expertise grasped over the years.

  8. 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

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ge, Jiajia; Santanam, Lakshmi; Noel, Camille

    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 disagreementmore » 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

  10. 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.

  11. Stress adapted embroidered meshes with a graded pattern design for abdominal wall hernia repair

    NASA Astrophysics Data System (ADS)

    Hahn, J.; Bittrich, L.; Breier, A.; Spickenheuer, A.

    2017-10-01

    Abdominal wall hernias are one of the most relevant injuries of the digestive system with 25 million patients in 2013. Surgery is recommended primarily using allogenic non-absorbable wrap-knitted meshes. These meshes have in common that their stress-strain behaviour is not adapted to the anisotropic behaviour of native abdominal wall tissue. The ideal mesh should possess an adequate mechanical behaviour and a suitable porosity at the same time. An alternative fabrication method to wrap-knitting is the embroidery technology with a high flexibility in pattern design and adaption of mechanical properties. In this study, a pattern generator was created for pattern designs consisting of a base and a reinforcement pattern. The embroidered mesh structures demonstrated different structural and mechanical characteristics. Additionally, the investigation of the mechanical properties exhibited an anisotropic mechanical behaviour for the embroidered meshes. As a result, the investigated pattern generator and the embroidery technology allow the production of stress adapted mesh structures that are a promising approach for hernia reconstruction.

  12. Perforator-Guided Drug Injection in the Treatment of Abdominal Wall Pain.

    PubMed

    Weum, Sven; de Weerd, Louis

    2016-07-01

    Pain from the abdominal wall can be caused by nerve entrapment, a condition called abdominal cutaneous nerve entrapment syndrome (ACNES). As an alternative to surgery, ACNES may be treated with injection of local anesthetics, corticosteroids, or botulinum toxin at the point of maximal pain. The point of maximal pain was marked on the abdominal skin. Using color Doppler ultrasound, the corresponding exit point of perforating blood vessels through the anterior fascia of the rectus abdominis muscle was identified. Ultrasound-guided injection of botulinum toxin in close proximity to the perforator's exit point was performed below and above the muscle fascia. The technique was used from 2008 to 2014 on 15 patients in 46 sessions with a total of 128 injections without complications. The injection technique provided safe and accurate administration of the drug in proximity to the affected cutaneous nerves. The effect of botulinum toxin on ACNES is beyond the scope of this article. Perforator-guided injection enables precise drug administration at the location of nerve entrapment in ACNES in contrast to blind injections. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Motion Tracking of the Carotid Artery Wall From Ultrasound Image Sequences: a Nonlinear State-Space Approach.

    PubMed

    Gao, Zhifan; Li, Yanjie; Sun, Yuanyuan; Yang, Jiayuan; Xiong, Huahua; Zhang, Heye; Liu, Xin; Wu, Wanqing; Liang, Dong; Li, Shuo

    2018-01-01

    The motion of the common carotid artery (CCA) wall has been established to be useful in early diagnosis of atherosclerotic disease. However, tracking the CCA wall motion from ultrasound images remains a challenging task. In this paper, a nonlinear state-space approach has been developed to track CCA wall motion from ultrasound sequences. In this approach, a nonlinear state-space equation with a time-variant control signal was constructed from a mathematical model of the dynamics of the CCA wall. Then, the unscented Kalman filter (UKF) was adopted to solve the nonlinear state transfer function in order to evolve the state of the target tissue, which involves estimation of the motion trajectory of the CCA wall from noisy ultrasound images. The performance of this approach has been validated on 30 simulated ultrasound sequences and a real ultrasound dataset of 103 subjects by comparing the motion tracking results obtained in this study to those of three state-of-the-art methods and of the manual tracing method performed by two experienced ultrasound physicians. The experimental results demonstrated that the proposed approach is highly correlated with (intra-class correlation coefficient ≥ 0.9948 for the longitudinal motion and ≥ 0.9966 for the radial motion) and well agrees (the 95% confidence interval width is 0.8871 mm for the longitudinal motion and 0.4159 mm for the radial motion) with the manual tracing method on real data and also exhibits high accuracy on simulated data (0.1161 ~ 0.1260 mm). These results appear to demonstrate the effectiveness of the proposed approach for motion tracking of the CCA wall.

  14. Robust estimation of carotid artery wall motion using the elasticity-based state-space approach.

    PubMed

    Gao, Zhifan; Xiong, Huahua; Liu, Xin; Zhang, Heye; Ghista, Dhanjoo; Wu, Wanqing; Li, Shuo

    2017-04-01

    The dynamics of the carotid artery wall has been recognized as a valuable indicator to evaluate the status of atherosclerotic disease in the preclinical stage. However, it is still a challenge to accurately measure this dynamics from ultrasound images. This paper aims at developing an elasticity-based state-space approach for accurately measuring the two-dimensional motion of the carotid artery wall from the ultrasound imaging sequences. In our approach, we have employed a linear elasticity model of the carotid artery wall, and converted it into the state space equation. Then, the two-dimensional motion of carotid artery wall is computed by solving this state-space approach using the H ∞ filter and the block matching method. In addition, a parameter training strategy is proposed in this study for dealing with the parameter initialization problem. In our experiment, we have also developed an evaluation function to measure the tracking accuracy of the motion of the carotid artery wall by considering the influence of the sizes of the two blocks (acquired by our approach and the manual tracing) containing the same carotid wall tissue and their overlapping degree. Then, we have compared the performance of our approach with the manual traced results drawn by three medical physicians on 37 healthy subjects and 103 unhealthy subjects. The results have showed that our approach was highly correlated (Pearson's correlation coefficient equals 0.9897 for the radial motion and 0.9536 for the longitudinal motion), and agreed well (width the 95% confidence interval is 89.62 µm for the radial motion and 387.26 µm for the longitudinal motion) with the manual tracing method. We also compared our approach to the three kinds of previous methods, including conventional block matching methods, Kalman-based block matching methods and the optical flow. Altogether, we have been able to successfully demonstrate the efficacy of our elasticity-model based state-space approach (EBS) for

  15. Gas gangrene of the abdominal wall due to late-onset enteric fistula after polyester mesh repair of an incisional hernia.

    PubMed

    Moussi, A; Daldoul, S; Bourguiba, B; Othmani, D; Zaouche, A

    2012-04-01

    The occurrence of enteric fistulae after wall repair using a prosthetic mesh is a serious but, fortunately, rare complication. We report the case of a 66-year-old diabetic man who presented with gas gangrene of the abdominal wall due to an intra-abdominal abscess caused by intestinal erosion six years after an incisional hernia repair using a polyester mesh. The aim of this case report is to illustrate the seriousness of enteric fistula after parietal repair using a synthetic material.

  16. Remarkably enhanced current-driven 360° domain wall motion in nanostripe by tuning in-plane biaxial anisotropy.

    PubMed

    Su, Yuanchang; Weng, Lianghao; Dong, Wenjun; Xi, Bin; Xiong, Rui; Hu, Jingguo

    2017-10-17

    By micromagnetic simulations, we study the current-driven 360° domain wall (360DW) motion in ferromagnetic nanostripe with an in-plane biaxial anisotropy. We observe the critical annihilation current of 360° domain wall can be enhanced through such a type of anisotropy, the reason of which is the suppression of out-of-plane magnetic moments generated simultaneously with domain-wall motion. In details, We have found that the domain-wall width is only related to K y  - K x , with K x(y) the anisotropy constant in x(y) direction. Taking domain-wall width into consideration, a prior choice is to keep K y  ≈ K x with large enough K. The mode of domain-wall motion has been investigated as well. The traveling-wave-motion region increases with K, while the average DW velocity is almost unchanged. Another noteworthy feature is that a Walker-breakdown-like motion exists before annihilation. In this region, though domain wall moves with an oscillating behavior, the average velocity does not reduce dramatically, but even rise again for a large K.

  17. Tomodensitometric survey of the distance between thoracic and abdominal vital organs and the wall according to BMI, abdominal diameter and gender: proposition of an indicative chart for the forensic activities.

    PubMed

    Venara, A; Gaudin, A; Lebigot, J; Airagnes, G; Hamel, J F; Jousset, N; Ridereau-Zins, C; Mauillon, D; Rouge-Maillart, C

    2013-06-10

    Forensic doctors are frequently asked by magistrates when dealing principally with knife wounds, about the depth of the blade which may have penetrated the victim's body. Without the use of imaging, it is often difficult to respond to this question, even in an approximate way. Knowledge of the various distances between organs and the skin wall would allow an assessment to be made of the minimum blade length required to obtain the injuries observed. The objective of this study is thus to determine average distances between the vital organs of the thorax and abdomen, and the skin wall, taking into account the person's body mass index (BMI). This is a prospective single-center study, carried out over a 2-month period at University Hospital in Angers. A sample of 200 people was studied. The inclusion criteria were as follows: all patients coming to the radiology department and the emergency department for an abdominal, thoracic or thoraco-abdominal scan with injection. The exclusion criteria included patients presenting a large lymphoma, a large abdominal or retroperitoneal tumor, a tumor in one of the organs targeted by our study and patients presenting ascites. The organs focused on were: the pericardium, pleura, aorta, liver, spleen, kidneys, abdominal aorta and femoral arteries. The shortest distance between the organ and the skin wall was noted. Median distances were calculated according to gender, abdominal diameter and BMI. We associated these values to propose an indicative chart which may be used by doctors in connection with their forensic activities. The problem of the depth of a wound is frequently exposed to the expert. Without a reliable tool, it is difficult to value and a personal interpretation is often done. Even if, in current days, tomodensitometry is frequently done in vivo or after death, measurement can be difficult because of the local conditions. We classified values according to the different factors of fat repartition (BMI, abdominal diameter

  18. Isometric abdominal wall muscle strength assessment in individuals with incisional hernia: a prospective reliability study.

    PubMed

    Jensen, K K; Kjaer, M; Jorgensen, L N

    2016-12-01

    To determine the reliability of measurements obtained by the Good Strength dynamometer, determining isometric abdominal wall and back muscle strength in patients with ventral incisional hernia (VIH) and healthy volunteers with an intact abdominal wall. Ten patients with VIH and ten healthy volunteers with an intact abdominal wall were each examined twice with a 1 week interval. Examination included the assessment of truncal flexion and extension as measured with the Good Strength dynamometer, the completion of the International Physical Activity Questionnaire (IPAQ) and the self-assessment of truncal strength on a visual analogue scale (SATS). The test-retest reliability of truncal flexion and extension was assessed by interclass correlation coefficient (ICC), and Bland and Altman graphs. Finally, correlations between truncal strength, and IPAQ and SATS were examined. Truncal flexion and extension showed excellent test-retest reliability for both patients with VIH (ICC 0.91 and 0.99) and healthy controls (ICC 0.97 and 0.96). Bland and Altman plots showed that no systematic bias was present for neither truncal flexion nor extension when assessing reliability. For patients with VIH, no significant correlations between objective measures of truncal strength and IPAQ or SATS were found. For healthy controls, both truncal flexion (τ 0.58, p = 0.025) and extension (τ 0.58, p = 0.025) correlated significantly with SATS, while no other significant correlation between truncal strength measures and IPAQ was found. The Good Strength dynamometer provided a reliable, low-cost measure of truncal flexion and extension in patients with VIH.

  19. 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.

  20. Comparison of the sonographic features of the abdominal wall muscles and connective tissues in individuals with and without lumbopelvic pain.

    PubMed

    Whittaker, Jackie L; Warner, Martin B; Stokes, Maria

    2013-01-01

    Cross-sectional, case-control study. To measure and compare the resting thickness of the 4 abdominal wall muscles, their associated perimuscular connective tissue (PMCT), and interrecti distance (IRD) in persons with and without lumbopelvic pain (LPP), using ultrasound imaging. The muscles and PMCT of the abdominal wall assist in controlling the spine. Functional deficits of the abdominal wall muscles have been detected in populations with LPP. Investigations of the abdominal wall in those with LPP are primarily concerned with muscle, most commonly the transversus abdominis (TrA) and internal oblique (IO). Because the abdominal wall functions as a unit, all 4 abdominal muscles and their associated connective tissues should be considered concurrently. B-mode ultrasound imaging was used to measure the resting thickness of the rectus abdominis (RA), external oblique, IO, and TrA muscles; the PMCT planes; and IRD in 50 male and female subjects, 25 with and 25 without LPP (mean ± SD age, 36.3 ± 9.4 and 46.6 ± 8.0 years, respectively). Univariate correlation analysis was used to identify covariates. Analyses of covariance (ANCOVAs) and the Kruskal-Wallis test (IRD) were used to compare cohorts (α = .05). The LPP cohort had less total abdominal muscle thickness (LPP mean ± SD, 18.9 ± 3.0 mm; control, 20.3 ± 3.0 mm; ANCOVA adjusted for body mass index, P = .03), thicker PMCT (LPP, 5.5 ± 0.2 mm; control, 4.3 ± 0.2 mm; ANCOVA adjusted for body mass index, P = .007), and wider IRD (LPP, 11.5 ± 2.0 mm; control, 8.4 ± 1.8 mm; Kruskal-Wallis, P = .005). Analysis of individual muscle thickness revealed no difference in the external oblique, IO, and TrA, but a thinner RA in the LPP cohort (LPP mean ± SD, 7.8 ± 1.5 mm; control, 9.1 ± 1.2 mm; ANCOVA adjusted for body mass index, P<.001). To our knowledge, this is the first study to investigate the morphological characteristics of all 4 abdominal muscles and PMCT in individuals with LPP. The results suggest that there

  1. Abdominal wall reconstruction following removal of a chronically infected mid-urethral tape.

    PubMed

    Walker, Helen; Brooker, Thomas; Gelman, Wolf

    2009-10-01

    We report a rare postoperative complication of a mid-urethral tape. The patient presented with a chronic infection resistant to treatment with several weeks of antibiotics, with eventual surgical removal, and the resulting complications of an infected incisional hernia and vesico-cutaneous fistula required reconstruction of the abdominal wall with Permacol and excision of the vesico-cutaneous fistula. We also look briefly at the impact of health tourism on the National Health Service.

  2. Ab initio study of edge effect on relative motion of walls in carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Popov, Andrey M.; Lebedeva, Irina V.; Knizhnik, Andrey A.; Lozovik, Yurii E.; Potapkin, Boris V.

    2013-01-01

    Interwall interaction energies of double-walled nanotubes with long inner and short outer walls are calculated as functions of coordinates describing relative rotation and displacement of the walls using van der Waals corrected density functional theory. The magnitude of corrugation and the shape of the potential energy relief are found to be very sensitive to changes of the shorter wall length at subnanometer scale and atomic structure of the edges if at least one of the walls is chiral. Threshold forces required to start relative motion of the short walls and temperatures at which the transition between diffusive and free motion of the short walls takes place are estimated. The edges are also shown to provide a considerable contribution to the barrier to relative rotation of commensurate nonchiral walls. For such walls, temperatures of orientational melting, i.e., the crossover from rotational diffusion to free relative rotation, are estimated. The possibility to produce nanotube-based bolt/nut pairs and nanobearings is discussed.

  3. Annealing effect on current-driven domain wall motion in Pt/[Co/Ni] wire

    NASA Astrophysics Data System (ADS)

    Furuta, Masaki; Liu, Yang; Sepehri-Amin, Hossein; Hono, Kazuhiro; Zhu, Jian-Gang Jimmy

    2017-09-01

    The annealing effect on the efficiency of current-driven domain wall motion governed by the spin Hall effect in perpendicularly magnetized Pt/[Co/Ni] wires is investigated experimentally. Important physical parameters, such as the Dzyaloshinskii-Moriya Interaction (DMI), spin Hall angle, and perpendicular anisotropy field strength, for the domain wall motion are all characterized at each annealing temperature. It is found that annealing of wires at temperatures over 120 °C causes significant reduction of the domain wall velocity. Energy dispersive X-ray spectroscopy analysis shows pronounced Co diffusion across the Pt/Co interface resulted from annealing at relatively high temperatures. The combined modeling study shows that the reduction of DMI caused by annealing is mostly responsible for the domain wall velocity reduction due to annealing.

  4. The Effects of Modified Wall Squat Exercises on Average Adults’ Deep Abdominal Muscle Thickness and Lumbar Stability

    PubMed Central

    Cho, Misuk

    2013-01-01

    [Purpose] The purpose of this study was to compare the effects of bridge exercises applying the abdominal drawing-in method and modified wall squat exercises on deep abdominal muscle thickness and lumbar stability. [Subjects] A total of 30 subjects were equally divided into an experimental group and a control group. [Methods] The experimental group completed modified wall squat exercises, and the control group performed bridge exercises. Both did so for 30 minutes three times per week over a six-week period. Both groups’ transversus abdominis (Tra), internal oblique (IO), and multifidus muscle thickness were measured using ultrasonography, while their static lumbar stability and dynamic lumbar stability were measured using a pressure biofeedback unit. [Results] A comparison of the pre-intervention and post-intervention measures of the experimental group and the control group was made; the Tra and IO thicknesses were significantly different in both groups. [Conclusion] The modified wall squat exercise and bridge exercise affected the thicknesses of the Tra and the IO muscles. While the bridge exercise requirs space and a mattress to lie on, the modified wall squat exercise can be conveniently performed anytime. PMID:24259831

  5. 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.

  6. [Endoprosthetic replacement with lifting of abdominal wall in treatment of umbilical and postoperative ventral hernias].

    PubMed

    Sukhovatykh, B S; Valuyskaya, N M; Gerasimchuk, E V

    2015-01-01

    The results of complex clinical and ultrasonic investigation of abdominal wall and following surgical treatment in 60 women with umbilical and postoperative large ventral hernias combined with abdomen ptosis were analyzed. Patients were divided into 2 groups with 30 people per group. Endoprosthetic replacement of abdominal wall defect using standard polypropylene prosthesis was applied in the 1st group, endoprosthetic replacement with musculoaponeurotic tissues lifting in hypogastric area using original super lightweight polypropylenepolyvinylidenefluoride prosthesis--in the 2nd group. Polypropylene endoprosthesisconsist of main flap 15×15 cm with roundish edges and additional flap 5×40 cm in the form of wide stripe placed at the lower edge of main flap transversely to its direction. It was revealed increased physical health component in 1.8 times, psychic--in 2.5 times in the 2nd group. Thus number of excellent results increased on 33.3% and amount of satisfactory outcomes reduced on 30%.

  7. Necrotizing Fasciitis of the Abdominal Wall in a Premature Infant: A Case Study.

    PubMed

    Narvey, Michael; Byrne, Paul; Fraser, Debbie

    2017-01-01

    We present a first report of necrotizing fasciitis of the abdominal wall in a 23-day-of-age, former 32-week-gestation premature infant. She was successfully treated with antibiotics without the need for initial debridement. After reviewing the etiology of necrotizing fasciitis, we discuss the unique aspects of this case, including the noninvasive approach to initial treatment, which we consider significantly contributed to her survival.

  8. Abdominal hernias: Radiological features

    PubMed Central

    Lassandro, Francesco; Iasiello, Francesca; Pizza, Nunzia Luisa; Valente, Tullio; Stefano, Maria Luisa Mangoni di Santo; Grassi, Roberto; Muto, Roberto

    2011-01-01

    Abdominal wall hernias are common diseases of the abdomen with a global incidence approximately 4%-5%. They are distinguished in external, diaphragmatic and internal hernias on the basis of their localisation. Groin hernias are the most common with a prevalence of 75%, followed by femoral (15%) and umbilical (8%). There is a higher prevalence in males (M:F, 8:1). Diagnosis is usually made on physical examination. However, clinical diagnosis may be difficult, especially in patients with obesity, pain or abdominal wall scarring. In these cases, abdominal imaging may be the first clue to the correct diagnosis and to confirm suspected complications. Different imaging modalities are used: conventional radiographs or barium studies, ultrasonography and Computed Tomography. Imaging modalities can aid in the differential diagnosis of palpable abdominal wall masses and can help to define hernial contents such as fatty tissue, bowel, other organs or fluid. This work focuses on the main radiological findings of abdominal herniations. PMID:21860678

  9. The effectiveness of a pneumatic compression belt in reducing respiratory motion of abdominal tumors in patients undergoing stereotactic body radiotherapy.

    PubMed

    Lovelock, D Michael; Zatcky, Joan; Goodman, Karyn; Yamada, Yoshiya

    2014-06-01

    Abdominal compression using a pneumatic abdominal compression belt developed in-house has been used to reduce respiratory motion of patients undergoing hypo-fractionated or single fraction stereotactic radio-ablative therapy for abdominal cancers. The clinical objective of belt usage was to reduce the cranial-caudal (CC) respiratory motion of the tumor to 5 mm or less during both CT simulation and treatment. A retrospective analysis was done to determine the effectiveness of the device and associated clinical procedures to reduce the CC respiratory motion of the tumor. 42 patients treated for tumors in the liver (30), adrenal glands (6), pancreas (3) and lymph nodes (3) using high dose hypofractionated radiotherapy between 2004 and the present were eligible for analysis. All patients had 2-3 radiopaque fiducial markers implanted near the tumor prior to simulation, or had clips from prior surgery. Integral to the belt is an inflatable air bladder that is positioned over the abdomen. The pneumatic pressure was set to a level in consultation with the patient. The CC motion was measured fluoroscopically with and without pneumatic pressure. Pneumatic pressure was used at all treatments to reduce to CC motion to that achieved at simulation. The mean CC motion with the belt in place, but no additional air pressure was 11.4 mm with a range of 5-20 mm. With the pressure applied, the mean CC motion was reduced to 4.4 mm with a range of 1-8 mm (P-value < 0.001). The clinical objective of reducing the CC motion of the tumor to a maximum excursion of 5 mm or less was achieved in 93% of cases. The use of a pneumatic compression belt and associated clinical procedures was found to result in a significant and frequently substantial reduction in the CC motion of the tumor.

  10. Reconstruction with latissimus dorsi, external abdominal oblique and cranial sartorius muscle flaps for a large defect of abdominal wall in a dog after surgical removal of infiltrative lipoma

    PubMed Central

    FENG, Yu-Ching; CHEN, Kuan-Sheng; CHANG, Shih-Chieh

    2016-01-01

    This animal was presented with a large-sized infiltrative lipoma in the abdominal wall that had been noted for 4 years. This lipoma was confirmed by histological examination from a previous biopsy, and the infiltrative features were identified by a computerized tomography scan. The surgical removal created a large-sized abdominal defect that was closed by a combination of latissimus dorsi and external abdominal oblique muscle flaps in a pedicle pattern. A small dehiscence at the most distal end of the muscle flap resulted in a small-sized abdominal hernia and was repaired with cranial sartorius muscle flap 14 days after surgery. The dog was in good general health with no signs of tumor recurrence after 18 months of follow-up. PMID:27476526

  11. Evaluation of optical data gained by ARAMIS-measurement of abdominal wall movements for an anisotropic pattern design of stress-adapted hernia meshes produced by embroidery technology

    NASA Astrophysics Data System (ADS)

    Breier, A.; Bittrich, L.; Hahn, J.; Spickenheuer, A.

    2017-10-01

    For the sustainable repair of abdominal wall hernia the application of hernia meshes is required. One reason for the relapse of hernia after surgery is seen in an inadequate adaption of the mechanical properties of the mesh to the movements of the abdominal wall. Differences in the stiffness of the mesh and the abdominal tissue cause tension, friction and stress resulting in a deficient tissue response and subsequently in a recurrence of a hernia, preferentially in the marginal area of the mesh. Embroidery technology enables a targeted influence on the mechanical properties of the generated textile structure by a directed thread deposition. Textile parameters like stitch density, alignment and angle can be changed easily and locally in the embroidery pattern to generate a space-resolved mesh with mechanical properties adapted to the requirement of the surrounding tissue. To determine those requirements the movements of the abdominal wall and the resulting distortions need to be known. This study was conducted to gain optical data of the abdominal wall movements by non-invasive ARAMIS-measurement on 39 test persons to estimate direction and value of the major strains.

  12. Value of gated SPECT in the analysis of regional wall motion of the interventricular septum after coronary artery bypass grafting.

    PubMed

    Giubbini, Raffaele; Rossini, Pierluigi; Bertagna, Francesco; Bosio, Giovanni; Paghera, Barbara; Pizzocaro, Claudio; Canclini, Silvana; Terzi, Arturo; Germano, Guido

    2004-10-01

    The aim of this study was the evaluation of septal wall motion, perfusion and wall thickening after CABG in two groups of consecutive patients, one with grafted left anterior coronary artery and no history of myocardial infarction, and the other with previous anteroseptal myocardial infarction and impaired septal motion before surgery. The issue addressed was the ability of gated SPECT to differentiate between true paradoxical septal motion, characterised by paradoxical wall motion, depressed ejection fraction (EF), poor viability and compromised wall thickening, and pseudo-paradoxical motion, characterised by abnormal wall motion and regional EF but preserved perfusion and wall thickening. One hundred and thirty-two patients with previous anterior myocardial infarction, 82 patients with left anterior descending coronary disease and no history of myocardial infarction and 27 normal subjects underwent rest gated SPECT after 99mTc-sestamibi injection, according to the standard QGS protocol. Quantitative regional EF, regional perfusion, regional wall motion and regional wall thickening were determined using a 20-segment model. Despite the presence of similar regional wall motion impairment in patients with and patients without septal infarction, in terms of regional EF (2.5%+/-3% vs 1.9%+/-4.9% p=NS) and inward septal motion (3+/-4.9 mm vs 2.3+/-6.1 mm p=NS), significant differences were observed in both perfusion (74.7%+/-6.2% vs 63.3%+/-13%, p>0.0001) and regional wall thickening (17.2%+/-7.4% vs 12.6%+/-7.2%, p>0.0001). Gated SPECT with perfusion tracers can reliably differentiate pseudo-paradoxical from true paradoxical septal motion in patients with previous CABG, and it may be the method of choice for evaluating left ventricular performance in this patient population.

  13. Tissue-engineering with muscle fiber fragments improves the strength of a weak abdominal wall in rats.

    PubMed

    Jangö, Hanna; Gräs, Søren; Christensen, Lise; Lose, Gunnar

    2017-02-01

    Alternative approaches to reinforce the native tissue in patients with pelvic organ prolapse (POP) are needed to improve surgical outcome. Our aims were to develop a weakened abdominal wall in a rat model to mimic the weakened vaginal wall in women with POP and then evaluate the regenerative potential of a quickly biodegradable synthetic scaffold, methoxypolyethylene glycol polylactic-co-glycolic acid (MPEG-PLGA), seeded with autologous muscle fiber fragments (MFFs) using this model. In an initial pilot study with 15 animals, significant weakening of the abdominal wall and a feasible technique was established by creating a partial defect with removal of one abdominal muscle layer. Subsequently, 18 rats were evenly divided into three groups: (1) unrepaired partial defect; (2) partial defect repaired with MPEG-PLGA; (3) partial defect repaired with MPEG-PLGA and MFFs labeled with PKH26-fluorescence dye. After 8 weeks, we performed histopathological and immunohistochemical testing, fluorescence analysis, and uniaxial biomechanical testing. Both macroscopically and microscopically, the MPEG-PLGA scaffold was fully degraded, with no signs of an inflammatory or foreign-body response. PKH26-positive cells were found in all animals from the group with added MFFs. Analysis of variance (ANOVA) showed a significant difference between groups with respect to load at failure (p = 0.028), and post hoc testing revealed that the group with MPEG-PLGA and MFFs showed a significantly higher strength than the group with MPEG-PLGA alone (p = 0.034). Tissue-engineering with MFFs seeded on a scaffold of biodegradable MPEG-PLGA might be an interesting adjunct to future POP repair.

  14. What is the evidence for the use of biologic or biosynthetic meshes in abdominal wall reconstruction?

    PubMed

    Köckerling, F; Alam, N N; Antoniou, S A; Daniels, I R; Famiglietti, F; Fortelny, R H; Heiss, M M; Kallinowski, F; Kyle-Leinhase, I; Mayer, F; Miserez, M; Montgomery, A; Morales-Conde, S; Muysoms, F; Narang, S K; Petter-Puchner, A; Reinpold, W; Scheuerlein, H; Smietanski, M; Stechemesser, B; Strey, C; Woeste, G; Smart, N J

    2018-04-01

    Although many surgeons have adopted the use of biologic and biosynthetic meshes in complex abdominal wall hernia repair, others have questioned the use of these products. Criticism is addressed in several review articles on the poor standard of studies reporting on the use of biologic meshes for different abdominal wall repairs. The aim of this consensus review is to conduct an evidence-based analysis of the efficacy of biologic and biosynthetic meshes in predefined clinical situations. A European working group, "BioMesh Study Group", composed of invited surgeons with a special interest in surgical meshes, formulated key questions, and forwarded them for processing in subgroups. In January 2016, a workshop was held in Berlin where the findings were presented, discussed, and voted on for consensus. Findings were set out in writing by the subgroups followed by consensus being reached. For the review, 114 studies and background analyses were used. The cumulative data regarding biologic mesh under contaminated conditions do not support the claim that it is better than synthetic mesh. Biologic mesh use should be avoided when bridging is needed. In inguinal hernia repair biologic and biosynthetic meshes do not have a clear advantage over the synthetic meshes. For prevention of incisional or parastomal hernias, there is no evidence to support the use of biologic/biosynthetic meshes. In complex abdominal wall hernia repairs (incarcerated hernia, parastomal hernia, infected mesh, open abdomen, enterocutaneous fistula, and component separation technique), biologic and biosynthetic meshes do not provide a superior alternative to synthetic meshes. The routine use of biologic and biosynthetic meshes cannot be recommended.

  15. Fractional Brownian motion with a reflecting wall.

    PubMed

    Wada, Alexander H O; Vojta, Thomas

    2018-02-01

    Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. Whereas the mean-square displacement of the particle shows the expected anomalous diffusion behavior 〈x^{2}〉∼t^{α}, the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case α>1, the particles accumulate at the barrier leading to a divergence of the probability density. For subdiffusion α<1, in contrast, the probability density is depleted close to the barrier. We discuss implications of these findings, in particular, for applications that are dominated by rare events.

  16. Fractional Brownian motion with a reflecting wall

    NASA Astrophysics Data System (ADS)

    Wada, Alexander H. O.; Vojta, Thomas

    2018-02-01

    Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. Whereas the mean-square displacement of the particle shows the expected anomalous diffusion behavior ˜tα , the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case α >1 , the particles accumulate at the barrier leading to a divergence of the probability density. For subdiffusion α <1 , in contrast, the probability density is depleted close to the barrier. We discuss implications of these findings, in particular, for applications that are dominated by rare events.

  17. Successful Treatment of Abdominal Cutaneous Entrapment Syndrome Using Ultrasound Guided Injection

    PubMed Central

    Hong, Myong Joo; Seo, Dong Hyuk

    2013-01-01

    There are various origins for chronic abdominal pain. About 10-30% of patients with chronic abdominal pain have abdominal wall pain. Unfortunately, abdominal wall pain is not thought to be the first origin of chronic abdominal pain; therefore, patients usually undergo extensive examinations, including diagnostic laparoscopic surgery. Entrapment of abdominal cutaneous nerves at the muscular foramen of the rectus abdominis is a rare cause of abdominal wall pain. If abdominal wall pain is considered in earlier stage of chronic abdominal pain, unnecessary invasive procedures are not required and patients will reach symptom free condition as soon as the diagnosis is made. Here, we report a case of successful treatment of a patient with abdominal cutaneous nerve entrapment syndrome by ultrasound guided injection therapy. PMID:23862004

  18. Robotic Transversus Abdominis Release (TAR): is it possible to offer minimally invasive surgery for abdominal wall complex defects?

    PubMed

    Amaral, Maria Vitória França DO; Guimarães, José Ricardo; Volpe, Paula; Oliveira, Flávio Malcher Martins DE; Domene, Carlos Eduardo; Roll, Sérgio; Cavazzola, Leandro Totti

    2017-01-01

    We describe the preliminary national experience and the early results of the use of robotic surgery to perform the posterior separation of abdominal wall components by the Transversus Abdominis Release (TAR) technique for the correction of complex defects of the abdominal wall. We performed the procedures between 04/2/2015 and 06/15/2015 and the follow-up time was up to six months, with a minimum of two months. The mean surgical time was five hours and 40 minutes. Two patients required laparoscopic re-intervention, since one developed hernia by peritoneal migration of the mesh and one had mesh extrusion. The procedure proved to be technically feasible, with a still long surgical time. Considering the potential advantages of robotic surgery and those related to TAR and the results obtained when these two techniques are associated, we conclude that they seem to be a good option for the correction of complex abdominal wall defects. RESUMO Descrevemos a experiência preliminar nacional na utilização da cirurgia robótica para realizar a separação posterior de componentes da parede abdominal pela técnica transversus abdominis release (TAR) na correção de defeitos complexos da parede abdominal e seus resultados precoces. As cirurgias foram realizadas entre 02/04/2015 e 15/06/2015 e o tempo de acompanhamento dos resultados foi de até seis meses, com tempo mínimo de dois meses. O tempo cirúrgico médio foi de cinco horas e 40 minutos. Dois pacientes necessitaram reintervenção por laparoscopia, pois um desenvolveu hérnia por migração peritoneal da tela e um teve escape da tela. A cirurgia provou ser factível do ponto de vista técnico, com um tempo cirúrgico ainda elevado. Tendo em vista as vantagens potenciais da cirurgia robótica e aquelas relacionadas ao TAR e os resultados obtidos ao se associar essas duas técnicas, conclui-se que elas parecem ser uma boa opção para a correção de defeitos complexos da parede abdominal.

  19. Minimization of Ohmic losses for domain wall motion in ferromagnetic nanowires

    NASA Astrophysics Data System (ADS)

    Abanov, Artem; Tretiakov, Oleg; Liu, Yang

    2011-03-01

    We study current-induced domain-wall motion in a narrow ferromagnetic wire. We propose a way to move domain walls with a resonant time-dependent current which dramatically decreases the Ohmic losses in the wire and allows driving of the domain wall with higher speed without burning the wire. For any domain wall velocity we find the time-dependence of the current needed to minimize the Ohmic losses. Below a critical domain-wall velocity specified by the parameters of the wire the minimal Ohmic losses are achieved by dc current. Furthermore, we identify the wire parameters for which the losses reduction from its dc value is the most dramatic. This work was supported by the NSF Grant No. 0757992 and Welch Foundation (A-1678).

  20. WE-G-BRD-01: A Data-Driven 4D-MRI Motion Model to Estimate Full Field-Of-View Abdominal Motion From 2D Image Navigators During MR-Linac Treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stemkens, B; Tijssen, RHN; Denis de Senneville, B Denis

    2015-06-15

    Purpose: To estimate full field-of-view abdominal respiratory motion from fast 2D image navigators using a 4D-MRI based motion model. This will allow for radiation dose accumulation mapping during MR-Linac treatment. Methods: Experiments were conducted on a Philips Ingenia 1.5T MRI. First, a retrospectively ordered 4D-MRI was constructed using 3D transient-bSSFP with radial in-plane sampling. Motion fields were calculated through 3D non-rigid registration. From these motion fields a PCA-based abdominal motion model was constructed and used to warp a 3D reference volume to fast 2D cine-MR image navigators that can be used for real-time tracking. To test this procedure, a time-seriesmore » consisting of two interleaved orthogonal slices (sagittal and coronal), positioned on the pancreas or kidneys, were acquired for 1m38s (dynamic scan-time=0.196ms), during normal, shallow, or deep breathing. The coronal slices were used to update the optimal weights for the first two PCA components, in order to warp the 3D reference image and construct a dynamic 4D-MRI time-series. The interleaved sagittal slices served as an independent measure to test the model’s accuracy and fit. Spatial maps of the root-mean-squared error (RMSE) and histograms of the motion differences within the pancreas and kidneys were used to evaluate the method. Results: Cranio-caudal motion was accurately calculated within the pancreas using the model for normal and shallow breathing with an RMSE of 1.6mm and 1.5mm and a histogram median and standard deviation below 0.2 and 1.7mm, respectively. For deep-breathing an underestimation of the inhale amplitude was observed (RMSE=4.1mm). Respiratory-induced antero-posterior and lateral motion were correctly mapped (RMSE=0.6/0.5mm). Kidney motion demonstrated good motion estimation with RMSE-values of 0.95 and 2.4mm for the right and left kidney, respectively. Conclusion: We have demonstrated a method that can calculate dynamic 3D abdominal motion in a large

  1. Impact of isotropic constitutive descriptions on the predicted peak wall stress in abdominal aortic aneurysms.

    PubMed

    Man, V; Polzer, S; Gasser, T C; Novotny, T; Bursa, J

    2018-03-01

    Biomechanics-based assessment of Abdominal Aortic Aneurysm (AAA) rupture risk has gained considerable scientific and clinical momentum. However, computation of peak wall stress (PWS) using state-of-the-art finite element models is time demanding. This study investigates which features of the constitutive description of AAA wall are decisive for achieving acceptable stress predictions in it. Influence of five different isotropic constitutive descriptions of AAA wall is tested; models reflect realistic non-linear, artificially stiff non-linear, or artificially stiff pseudo-linear constitutive descriptions of AAA wall. Influence of the AAA wall model is tested on idealized (n=4) and patient-specific (n=16) AAA geometries. Wall stress computations consider a (hypothetical) load-free configuration and include residual stresses homogenizing the stresses across the wall. Wall stress differences amongst the different descriptions were statistically analyzed. When the qualitatively similar non-linear response of the AAA wall with low initial stiffness and subsequent strain stiffening was taken into consideration, wall stress (and PWS) predictions did not change significantly. Keeping this non-linear feature when using an artificially stiff wall can save up to 30% of the computational time, without significant change in PWS. In contrast, a stiff pseudo-linear elastic model may underestimate the PWS and is not reliable for AAA wall stress computations. Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.

  2. Reconstruction of Abdominal Wall of a Chronically Infected Postoperative Wound with a Rectus Abdominis Myofascial Splitting Flap

    PubMed Central

    Bae, Sung Kyu; Kang, Seok Joo; Kim, Jin Woo; Kim, Young Hwan

    2013-01-01

    Background If a chronically infected abdominal wound develops, complications such as peritonitis and an abdominal wall defect could occur. This could prolong the patient's hospital stay and increase the possibility of re-operation or another infection as well. For this reason, a solution for infection control is necessary. In this study, surgery using a rectus abdominis muscle myofascial splitting flap was performed on an abdominal wall defect. Methods From 2009 to 2012, 5 patients who underwent surgery due to ovarian rupture, cesarean section, or uterine myoma were chosen. In each case, during the first week after operation, the wound showed signs of infection. Surgery was chosen because the wounds did not resolve with dressing. Debridement was performed along the previous operation wound and dissection of the skin was performed to separate the skin and subcutaneous tissue from the attenuated rectus muscle and Scarpa's fascial layers. Once the anterior rectus sheath and muscle were adequately mobilized, the fascia and muscle flap were advanced medially so that the skin defect could be covered for reconstruction. Results Upon 3-week follow-up after a rectus abdominis myofascial splitting flap operation, no major complication occurred. In addition, all of the patients showed satisfaction in terms of function and esthetics at 3 to 6 months post-surgery. Conclusions Using a rectus abdominis myofascial splitting flap has many esthetic and functional benefits over previous methods of abdominal defect treatment, and notably, it enabled infection control by reconstruction using muscle. PMID:23362477

  3. 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

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

    2014-07-01

    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. 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). 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. 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.

  4. Fast Numerical Simulation of Focused Ultrasound Treatments During Respiratory Motion With Discontinuous Motion Boundaries.

    PubMed

    Schwenke, Michael; Georgii, Joachim; Preusser, Tobias

    2017-07-01

    Focused ultrasound (FUS) is rapidly gaining clinical acceptance for several target tissues in the human body. Yet, treating liver targets is not clinically applied due to a high complexity of the procedure (noninvasiveness, target motion, complex anatomy, blood cooling effects, shielding by ribs, and limited image-based monitoring). To reduce the complexity, numerical FUS simulations can be utilized for both treatment planning and execution. These use-cases demand highly accurate and computationally efficient simulations. We propose a numerical method for the simulation of abdominal FUS treatments during respiratory motion of the organs and target. Especially, a novel approach is proposed to simulate the heating during motion by solving Pennes' bioheat equation in a computational reference space, i.e., the equation is mathematically transformed to the reference. The approach allows for motion discontinuities, e.g., the sliding of the liver along the abdominal wall. Implementing the solver completely on the graphics processing unit and combining it with an atlas-based ultrasound simulation approach yields a simulation performance faster than real time (less than 50-s computing time for 100 s of treatment time) on a modern off-the-shelf laptop. The simulation method is incorporated into a treatment planning demonstration application that allows to simulate real patient cases including respiratory motion. The high performance of the presented simulation method opens the door to clinical applications. The methods bear the potential to enable the application of FUS for moving organs.

  5. Minimization of Ohmic Losses for Domain Wall Motion in a Ferromagnetic Nanowire

    NASA Astrophysics Data System (ADS)

    Tretiakov, O. A.; Liu, Y.; Abanov, Ar.

    2010-11-01

    We study current-induced domain-wall motion in a narrow ferromagnetic wire. We propose a way to move domain walls with a resonant time-dependent current which dramatically decreases the Ohmic losses in the wire and allows driving of the domain wall with higher speed without burning the wire. For any domain-wall velocity we find the time dependence of the current needed to minimize the Ohmic losses. Below a critical domain-wall velocity specified by the parameters of the wire the minimal Ohmic losses are achieved by dc current. Furthermore, we identify the wire parameters for which the losses reduction from its dc value is the most dramatic.

  6. Use of Epidural Analgesia as an Adjunct in Elective Abdominal Wall Reconstruction: A Review of 4983 Cases.

    PubMed

    Karamanos, Efstathios; Dream, Sophie; Falvo, Anthony; Schmoekel, Nathan; Siddiqui, Aamir

    2017-01-01

    Use of epidural analgesia in patients undergoing elective abdominal wall reconstruction is common. To assess the impact of epidural analgesia in patients undergoing abdominal wall reconstruction. All patients who underwent elective ventral hernia repair from 2005 to 2014 were retrospectively identified. Patients were divided into two groups by the postoperative use of epidural analgesics as an adjunct analgesic method. Preoperative comorbidities, American Society of Anesthesiologists status, operative findings, postoperative pain management, and venothromboembolic prophylaxis were extracted from the database. Logistic regressions were performed to assess the impact of epidural use. Severity of pain on postoperative days 1 and 2. During the study period, 4983 patients were identified. Of those, 237 patients (4.8%) had an epidural analgesic placed. After adjustment for differences between groups, use of epidural analgesia was associated with significantly lower rates of 30-day presentation to the Emergency Department (adjusted odds ratio [AOR] = 0.53, 95% confidence interval [CI] = 0.32-0.87, adjusted p = 0.01). Use of epidural analgesia resulted in higher odds of abscess development (AOR = 5.89, CI = 2.00-17.34, adjusted p < 0.01) and transfusion requirement (AOR = 2.92, CI = 1.34-6.40, adjusted p < 0.01). Use of epidural analgesia resulted in a significantly lower pain score on postoperative day 1 (3 vs 4, adjusted p < 0.01). Use of epidural analgesia in patients undergoing abdominal wall reconstruction may result in longer hospital stay and higher incidence of complications while having no measurable positive clinical impact on pain control.

  7. 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.

  8. Does quantitative left ventricular regional wall motion change after fibrous tissue resection in endomyocardial fibrosis?

    PubMed

    Salemi, Vera Maria Cury; Fernandes, Fabio; Sirvente, Raquel; Nastari, Luciano; Rosa, Leonardo Vieira; Ferreira, Cristiano A; Pena, José Luiz Barros; Picard, Michael H; Mady, Charles

    2009-01-01

    We compared left ventricular regional wall motion, the global left ventricular ejection fraction, and the New York Heart Association functional class pre- and postoperatively. Endomyocardial fibrosis is characterized by fibrous tissue deposition in the endomyocardium of the apex and/or inflow tract of one or both ventricles. Although left ventricular global systolic function is preserved, patients exhibit wall motion abnormalities in the apical and inferoapical regions. Fibrous tissue resection in New York Heart Association FC III and IV endomyocardial fibrosis patients has been shown to decrease morbidity and mortality. We prospectively studied 30 patients (20 female, 30+/-10 years) before and 5+/-8 months after surgery. The left ventricular ejection fraction was determined using the area-length method. Regional left ventricular motion was measured by the centerline method. Five left ventricular segments were analyzed pre- and postoperatively. Abnormality was expressed in units of standard deviation from the mean motion in a normal reference population. Left ventricular wall motion in the five regions did not differ between pre- and postoperative measurements. Additionally, the left ventricular ejection fraction did not change after surgery (0.45+/-0.13% x 0.43+/-0.12% pre- and postoperatively, respectively). The New York Heart Association functional class improved to class I in 40% and class II in 43% of patients postoperatively (p<0.05). Although endomyocardial fibrosis patients have improved clinical symptoms after surgery, the global left ventricular ejection fraction and regional wall motion in these patients do not change. This finding suggests that other explanations, such as improvements in diastolic function, may be operational.

  9. The stability of steady motion of magnetic domain wall: Role of higher-order spin-orbit torques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    He, Peng-Bin, E-mail: hepengbin@hnu.edu.cn; Yan, Han; Cai, Meng-Qiu

    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 bemore » 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.« less

  10. 4D-CT scans reveal reduced magnitude of respiratory liver motion achieved by different abdominal compression plate positions in patients with intrahepatic tumors undergoing helical tomotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Yong, E-mail: hu.yong@zs-hospital.sh.cn; Zhou,

    Purpose: While abdominal compression (AC) can be used to reduce respiratory liver motion in patients receiving helical tomotherapy for hepatocellular carcinoma, the nature and extent of this effect is not well described. The purpose of this study was to evaluate the changes in magnitude of three-dimensional liver motion with abdominal compression using four-dimensional (4D) computed tomography (CT) images of several plate positions. Methods: From January 2012 to October 2015, 72 patients with intrahepatic carcinoma and divided into four groups underwent 4D-CT scans to assess respiratory liver motion. Of the 72 patients, 19 underwent abdominal compression of the cephalic area betweenmore » the subxiphoid and umbilicus (group A), 16 underwent abdominal compression of the caudal region between the subxiphoid area and the umbilicus (group B), 11 patients underwent abdominal compression of the caudal umbilicus (group C), and 26 patients remained free breathing (group D). 4D-CT images were sorted into ten-image series, according to the respiratory phase from the end inspiration to the end expiration, and then transferred to treatment planning software. All liver contours were drawn by a single physician and confirmed by a second physician. Liver relative coordinates were automatically generated to calculate the liver respiratory motion in different axial directions to compile the 10 ten contours into a single composite image. Differences in respiratory liver motion were assessed with a one-way analysis of variance test of significance. Results: The average respiratory liver motion in the Y axial direction was 4.53 ± 1.16, 7.56 ± 1.30, 9.95 ± 2.32, and 9.53 ± 2.62 mm in groups A, B, C, and D, respectively, with a significant change among the four groups (p < 0.001). Abdominal compression was most effective in group A (compression plate on the subxiphoid area), with liver displacement being 2.53 ± 0.93, 4.53 ± 1.16, and 2.14 ± 0.92 mm on the X-, Y-, and Z

  11. Numerical simulation of microcarrier motion in a rotating wall vessel bioreactor.

    PubMed

    Ju, Zhi-Hao; Liu, Tian-Qing; Ma, Xue-Hu; Cui, Zhan-Feng

    2006-06-01

    To analyze the forces of rotational wall vessel (RWV) bioreactor on small tissue pieces or microcarrier particles and to determine the tracks of microcarrier particles in RWV bioreactor. The motion of the microcarrier in the rotating wall vessel (RWV) bioreactor with both the inner and outer cylinders rotating was modeled by numerical simulation. The continuous trajectory of microcarrier particles, including the possible collision with the wall was obtained. An expression between the minimum rotational speed difference of the inner and outer cylinders and the microcarrier particle or aggregate radius could avoid collisions with either wall. The range of microcarrier radius or tissue size, which could be safely cultured in the RWV bioreactor, in terms of shear stress level, was determined. The model works well in describing the trajectory of a heavier microcarrier particle in rotating wall vessel.

  12. Learning curves in abdominal wall reconstruction with components separation: one step closer toward improving outcomes and reducing complications.

    PubMed

    Hultman, Charles Scott; Clayton, John L; Kittinger, Benjamin J; Tong, Winnie M

    2014-01-01

    Learning curves are characterized by incremental improvement of a process, through repetition and reduction in variability, but can be disrupted with the emergence of new techniques and technologies. Abdominal wall reconstruction continues to evolve, with the introduction of components separation in the 1990s and biologic mesh in the 2000s. As such, attempts at innovation may impact the success of reconstructive outcomes and yield a changing set of complications. The purpose of this project was to describe the paradigm shift that has occurred in abdominal wall reconstruction during the past 10 years, focusing on the incorporation of new materials and methods. We reviewed 150 consecutive patients who underwent abdominal wall reconstruction of midline defects with components separation, from 2000 to 2010. Both univariate and multivariate logistic regression analyses were performed to identify risk factors for complications. Patients were stratified into the following periods: early (2000-2003), middle (2004-2006), and late (2007-2010). From 2000 to 2010, we performed 150 abdominal wall reconstructions with components separation [mean age, 50.2 years; body mass index (BMI), 30.4; size of defect, 357 cm; length of stay, 9.6 days; follow-up, 4.4 years]. Primary fascial closure was performed in 120 patients. Mesh was used in 114 patients in the following locations: overlay (n = 28), inlay (n = 30), underlay (n = 54), and unknown (n = 2). Complications occurred in a bimodal distribution, highest in 2001 (introduction of biologic mesh) and 2008 (conversion from underlay to overlay location). Age, sex, history of smoking, defect size, and length of stay were not associated with incidence of complications. Unadjusted risk factors for seroma (16.8%) were elevated BMI, of previous hernia repairs, use of overlay mesh, and late portion of the learning curve, with logistic regression supporting only late portion of the learning curve [odds ratio (OR), 4.3; 95% confidence interval

  13. Assessment of LVEF using a new 16-segment wall motion score in echocardiography.

    PubMed

    Lebeau, Real; Serri, Karim; Lorenzo, Maria Di; Sauvé, Claude; Le, Van Hoai Viet; Soulières, Vicky; El-Rayes, Malak; Pagé, Maude; Zaïani, Chimène; Garot, Jérôme; Poulin, Frédéric

    2018-06-01

    Simpson biplane method and 3D by transthoracic echocardiography (TTE), radionuclide angiography (RNA) and cardiac magnetic resonance imaging (CMR) are the most accepted techniques for left ventricular ejection fraction (LVEF) assessment. Wall motion score index (WMSI) by TTE is an accepted complement. However, the conversion from WMSI to LVEF is obtained through a regression equation, which may limit its use. In this retrospective study, we aimed to validate a new method to derive LVEF from the wall motion score in 95 patients. The new score consisted of attributing a segmental EF to each LV segment based on the wall motion score and averaging all 16 segmental EF into a global LVEF. This segmental EF score was calculated on TTE in 95 patients, and RNA was used as the reference LVEF method. LVEF using the new segmental EF 15-40-65 score on TTE was compared to the reference methods using linear regression and Bland-Altman analyses. The median LVEF was 45% (interquartile range 32-53%; range from 15 to 65%). Our new segmental EF 15-40-65 score derived on TTE correlated strongly with RNA-LVEF ( r  = 0.97). Overall, the new score resulted in good agreement of LVEF compared to RNA (mean bias 0.61%). The standard deviations (s.d.s) of the distributions of inter-method difference for the comparison of the new score with RNA were 6.2%, indicating good precision. LVEF assessment using segmental EF derived from the wall motion score applied to each of the 16 LV segments has excellent correlation and agreement with a reference method. © 2018 The authors.

  14. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... plaque buildup causes the walls of the abdominal aorta to become weak and bulge outward like a ... treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, is a ...

  15. Kilovoltage imaging of implanted fiducials to monitor intrafraction motion with abdominal compression during stereotactic body radiotherapy for GI tumors

    PubMed Central

    Yorke, Ellen; Xiong, Ying; Han, Qian; Zhang, Pengpeng; Mageras, Gikas; Lovelock, Michael; Pham, Hai; Xiong, Jian-Ping; Goodman, Karyn A.

    2017-01-01

    Purpose/Objective To assess intrafraction respiratory motion using a commercial kilovoltage imaging system for abdominal tumor patients with implanted fiducials and breathing constrained by pneumatic compression during stereotactic body radiotherapy (sbrt). Methods and Materials A pneumatic compression belt limited respiratory motion in 19 patients with radiopaque fiducials in or near their tumor during sbrt for abdominal tumors. Kilovoltage images were acquired at 5–6 sec intervals during treatment using a commercial system. Intrafractional fiducial displacements were measured using in-house software. The dosimetric effect of the observed displacements was calculated for three sessions for each patient. Results Intrafraction displacement patterns varied between patients and between individual treatment sessions. Averaged over 19 patients, 73 sessions, 7.6% of craniocaudal displacements exceeded 0.5 cm and 1.2% exceeded 0.75 cm. The calculated single session dose to 95% of gross tumor volume (GTVD95) differed from planned by an average of −1.2% (−11.1%−4.8%) but only for 4 patients was total 3-session calculated GTVD95 over 3% different from planned Conclusions Our pneumatic compression limited intrafractional abdominal target motion, maintained target position established at setup, and was moderately effective in preserving coverage. Commercially available intrafractional imaging is useful for surveillance but can be made more effective and reliable. PMID:26797539

  16. Non-cross-linked porcine acellular dermal matrices for abdominal wall reconstruction.

    PubMed

    Burns, Nadja K; Jaffari, Mona V; Rios, Carmen N; Mathur, Anshu B; Butler, Charles E

    2010-01-01

    Non-cross-linked porcine acellular dermal matrices have been used clinically for abdominal wall repair; however, their biologic and mechanical properties and propensity to form visceral adhesions have not been studied. The authors hypothesized that their use would result in fewer, weaker visceral adhesions than polypropylene mesh when used to repair ventral hernias and form a strong interface with the surrounding musculofascia. Thirty-four guinea pigs underwent inlay repair of surgically created ventral hernias using polypropylene mesh, porcine acellular dermal matrix, or a composite of the two. The animals were killed at 4 weeks, and the adhesion tenacity grade and surface area of the repair site involved by adhesions were measured. Sections of the repair sites, including the implant-musculofascia interface, underwent histologic analysis and uniaxial mechanical testing. The incidence of bowel adhesions to the repair site was significantly lower with the dermal matrix (8 percent, p < 0.01) and the matrix/mesh combination (0 percent, p < 0.001) than with polypropylene mesh alone (70 percent). The repairs made with the matrix or the matrix/mesh combination, compared with the polypropylene mesh repairs, had significantly lower mean adhesion surface areas [12.8 percent (p < 0.001), 9.2 percent (p < 0.001), and 79.9 percent] and grades [0.6 (p < 0.001), 0.6 (p < 0.001), and 2.9]. The dermal matrix underwent robust cellular and vascular infiltration. The ultimate tensile strength at the implant-musculofascia interface was similar in all groups. Porcine acellular dermal matrix becomes incorporated into the host tissue and causes fewer adhesions to repair sites than does polypropylene mesh, with similar implant-musculofascia interface strength. It also inhibits adhesions to adjacent dermal matrix in the combination repairs. It has distinct advantages over polypropylene mesh for complex abdominal wall repairs, particularly when material placement directly over bowel is

  17. Sporadic extra abdominal wall desmoid-type fibromatosis: surgical resection can be safely limited to a minority of patients.

    PubMed

    Colombo, C; Miceli, R; Le Péchoux, C; Palassini, E; Honoré, C; Stacchiotti, S; Mir, O; Casali, P G; Dômont, J; Fiore, M; Le Cesne, A; Gronchi, A; Bonvalot, S

    2015-01-01

    To analyse the natural history of extra-abdominal wall desmoid-type fibromatosis (DF) and compare outcome in patients who underwent initial surgery with those who did not. All consecutive patients affected by primary sporadic extra-abdominal wall DF observed between January 1992 and December 2012 were included. Patients were divided into surgical (SG) or non-surgical groups (NSG) according to initial treatment. Relapse free survival was calculated for SG, and crude cumulative incidence (CCI) of switching to surgery or other treatments for NSG. 216 patients were identified, 94 in SG (43%), 122 in NSG (57%). A shift towards a more systematic use of a conservative approach (78% of all comers) was observed in the latter years (2006-2012), although a small proportion of patients (28%) had been offered the conservative strategy even in the early period (1992-2005). Median follow-up (FU) was 49 mo. (interquartile (IQ), 20-89 mo.), 76 months for SG and 39 months for NSG. 5-year relapse-free survival (RFS) for SG was 80% (95% confidence interval (CI), 72-89%). For the NSG, 5-year CCI of switching to surgery was 5% (95% CI: 1.7%, 14%), and 51% to other treatments (95% CI: 41%, 65%). 27 (20%) NSG patients underwent spontaneous regression. A non-surgical approach to extra-abdominal wall DF allowed surgery to be avoided in the majority of patients. This approach can be safely proposed and surgery offered as an option in selected cases. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Strain measurement of abdominal aortic aneurysm with real-time 3D ultrasound speckle tracking.

    PubMed

    Bihari, P; Shelke, A; Nwe, T H; Mularczyk, M; Nelson, K; Schmandra, T; Knez, P; Schmitz-Rixen, T

    2013-04-01

    Abdominal aortic aneurysm rupture is caused by mechanical vascular tissue failure. Although mechanical properties within the aneurysm vary, currently available ultrasound methods assess only one cross-sectional segment of the aorta. This study aims to establish real-time 3-dimensional (3D) speckle tracking ultrasound to explore local displacement and strain parameters of the whole abdominal aortic aneurysm. Validation was performed on a silicone aneurysm model, perfused in a pulsatile artificial circulatory system. Wall motion of the silicone model was measured simultaneously with a commercial real-time 3D speckle tracking ultrasound system and either with laser-scan micrometry or with video photogrammetry. After validation, 3D ultrasound data were collected from abdominal aortic aneurysms of five patients and displacement and strain parameters were analysed. Displacement parameters measured in vitro by 3D ultrasound and laser scan micrometer or video analysis were significantly correlated at pulse pressures between 40 and 80 mmHg. Strong local differences in displacement and strain were identified within the aortic aneurysms of patients. Local wall strain of the whole abdominal aortic aneurysm can be analysed in vivo with real-time 3D ultrasound speckle tracking imaging, offering the prospect of individual non-invasive rupture risk analysis of abdominal aortic aneurysms. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  19. Motion of a Spherical Domain Wall and the Large-Scale Structure Formation

    NASA Astrophysics Data System (ADS)

    Yamamoto, K.; Tomita, K.

    1991-11-01

    The evolution of a wall-like structure in the universe is investigated by assuming a simplified model of a domain wall. The domain wall is approximated as a thin spherical shell with domain wall-like matter, which is assumed to interact with dust-like dark matter in an entirely inelastic manner, and its motion in an expanding universe is numerically studied in the general-relativistic treatment. We evaluate the lifetime of the wall, which is defined as the characteristic time for the wall to shrink due to its own tension. It is necessary that this time is not smaller than the cosmic age, in order that the walls avoid the collapse to the present time and play an important role in the structure formation of the universe. It is shown that, in spite of the above interaction, the strong restriction is imposed on the surface density of the domain walls and the allowed values are too small to have any influences on the background model.

  20. In vitro comparison of intra-abdominal hypertension development after different temporary abdominal closure techniques.

    PubMed

    Benninger, Emanuel; Labler, Ludwig; Seifert, Burkhardt; Trentz, Otmar; Menger, Michael D; Meier, Christoph

    2008-01-01

    To compare volume reserve capacity (VRC) and development of intra-abdominal hypertension after different in vitro temporary abdominal closure (TAC) techniques. A model of the abdomen was designed. The abdominal wall was simulated with polychloroprene, a synthetic rubber compound. A lentil-shaped defect of 150 cm(2) was cut into the anterior aspect of the abdominal wall. TAC of this defect was performed by a zipper system (ZS), a bag silo closure (BSC), or a vacuum assisted closure (VAC) with subatmospheric pressures ranging from 0- to 200 mmHg. The model with intact abdominal wall served as reference. The model was filled with water to baseline level. The intra-abdominal pressure was increased in 2 mmHg steps from baseline level (6 mmHg) to 40 mmHg by adding volume to the system according to a standardized protocol. VRC with corresponding intra-abdominal pressure were analyzed and compared for the different TAC techniques. VRC was the highest after BSC at all pressure levels studied (P < 0.05). VAC and ZS resulted in significantly lower VRC compared with BSC and reference (P < 0.05). The magnitude of negative pressure on the VAC did not significantly influence the VRC. In the present in vitro model, BSC demonstrated the highest VRC of all evaluated TAC techniques. Different levels of subatmospheric pressures applied to the VAC did not affect VRC. The results for ZS and VAC indicate that these TAC techniques may increase the risk for recurrent intra-abdominal hypertension and should therefore not be used in high-risk patients during the initial phase after abdominal decompression.

  1. Volume rather than flow incentive spirometry is effective in improving chest wall expansion and abdominal displacement using optoelectronic plethysmography.

    PubMed

    Paisani, Denise de Moraes; Lunardi, Adriana Claudia; da Silva, Cibele Cristine Berto Marques; Porras, Desiderio Cano; Tanaka, Clarice; Carvalho, Celso Ricardo Fernandes

    2013-08-01

    Incentive spirometers are widely used in clinical practice and classified as flow-oriented (FIS) and volume-oriented (VIS). Until recently the respiratory inductive plethysmography used to evaluate the effects of incentive spirometry on chest wall mechanics presented limitations, which may explain why the impact of VIS and FIS remains poorly known. To compare the effects of VIS and FIS on thoracoabdominal mechanics and respiratory muscle activity in healthy volunteers. This cross-sectional trial assessed 20 subjects (12 female, ages 20-40 years, body mass index 20-30 kg/m(2)). All subjects performed 8 quiet breaths and 8 deep breaths with FIS and VIS, in a randomized order. We measured thoracoabdominal chest wall, upper and lower rib-cage, and abdominal volumes with optoelectronic plethysmography, and the muscle activity of the sternocleidomastoid and superior and inferior intercostal muscles with electromyography. VIS increased chest wall volume more than did FIS (P = .007) and induced a larger increase in the upper and lower rib-cages and abdomen (156%, 91%, and 151%, respectively, P < .001). By contrast, FIS induced more activity in the accessory muscles of respiration than did VIS (P < .001). VIS promotes a greater increase in chest wall volume, with a larger abdominal contribution and lower respiratory muscle activity, than does FIS in healthy adults.

  2. Is prophylactic embolization of the hepatic falciform artery needed before radioembolization in patients with 99mTc-MAA accumulation in the anterior abdominal wall?

    PubMed

    Ahmadzadehfar, Hojjat; Möhlenbruch, Markus; Sabet, Amir; Meyer, Carsten; Muckle, Marianne; Haslerud, Torjan; Wilhelm, Kai; Schild, Hans Heinz; Biersack, Hans Jürgen; Ezziddin, Samer

    2011-08-01

    While influx of chemoembolic agents into the hepatic falciform artery (HFA) from the hepatic artery can cause supraumbilical skin rash, epigastric pain and even skin necrosis, the significance of a patent HFA in patients undergoing radioembolization is not completely clear. Furthermore, the presence of tracer in the anterior abdominal wall seen in (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) images, which is generally performed prior to radioembolization, has been described as a sign of a patent HFA. The aim of this retrospective study was to evaluate the incidence and consequences of (99m)Tc-MAA accumulation in the anterior abdominal wall, indicating a patent HFA, in patients undergoing radioembolization of liver tumours. A total of 224 diagnostic hepatic angiograms combined with (99m)Tc-MAA SPECT/CT were acquired in 192 patients with different types of cancer, of whom 142 were treated with a total of 214 radioembolization procedures. All patients received a whole-body scan, and planar and SPECT/CT scans of the abdomen. Only patients with extrahepatic (99m)Tc-MAA accumulation in the anterior abdominal wall were included in this study. Posttreatment bremsstrahlung SPECT/CT and follow-up results for at least 3 months served as reference standards. Tracer accumulation in the anterior abdominal wall was present in pretreatment (99m)Tc-MAA SPECT/CT images of 18 patients (9.3%). The HFA was found and embolized by radiologists before treatment in one patient. In the remaining patients radioembolization was performed without any modification in the treatment plan despite the previously mentioned extrahepatic accumulation. Only one patient experienced abdominal muscle pain above the navel, which started 24 h after treatment and lasted for 48 h without any skin changes. The remaining patients did not experience any relevant side effects during the follow-up period. Side effects after radioembolization in patients with tracer accumulation in the anterior abdominal

  3. Wall stress reduction in abdominal aortic aneurysms as a result of polymeric endoaortic paving.

    PubMed

    Ashton, John H; Ayyalasomayajula, Avinash; Simon, Bruce R; Vande Geest, Jonathan P

    2011-06-01

    Polymeric endoaortic paving (PEAP) may improve endovascular repair of abdominal aortic aneurysms (AAA) since it has the potential to treat patients with complex AAA geometries while reducing the incidence of migration and endoleak. Polycaprolactone (PCL)/polyurethane (PU) blends are proposed as PEAP materials due to their range of mechanical properties, thermoformability, and resistance to biodegradation. In this study, the reduction in AAA wall stress that can be achieved using PEAP was estimated and compared to that resulting from stent-grafts. This was accomplished by mechanically modeling the anisotropic response of PCL/PU blends and implementing these results into finite element model (FEM) simulations. We found that at the maximum diameter of the AAA, the 50/50 and 10/90 PCL/PU blends reduced wall stress by 99 and 98%, respectively, while a stent-graft reduced wall stress by 99%. Our results also show that wall stress reduction increases with increasing PEAP thickness and PCL content in the blend ratio. These results indicate that PEAP can reduce AAA wall stress as effectively as a stent-graft. As such, we propose that PEAP may provide an improved treatment alternative for AAA, since many of the limitations of stent-grafts have the potential to be solved using this approach.

  4. Clostridial Gas Gangrene of the Abdominal Wall After Laparoscopic Cholecystectomy: A Case Report and Review.

    PubMed

    Harmsen, Annelieke M K; van Tol, Erik; Giannakopoulos, Georgios F; de Brauw, L Maurits

    2016-08-01

    Clostridial gas gangrene is a rare, yet severe, complication after laparoscopic cholecystectomy. We present a case report of a 48-year-old man with obesity, coronary artery disease, and diabetes, who developed clostridial gas gangrene of the abdominal wall after an uncomplicated laparoscopic cholecystectomy. Although the diagnosis was missed initially, successful radical surgical debridement was performed and the patient survived. Pathogenesis, symptoms, prognostic factors, and the best treatment are discussed.

  5. Changes in sitting posture induce multiplanar changes in chest wall shape and motion with breathing.

    PubMed

    Lee, Linda-Joy; Chang, Angela T; Coppieters, Michel W; Hodges, Paul W

    2010-03-31

    This study examined the effect of sitting posture on regional chest wall shape in three dimensions, chest wall motion (measured with electromagnetic motion analysis system), and relative contributions of the ribcage and abdomen to tidal volume (%RC/V(t)) (measured with inductance plethysmography) in 7 healthy volunteers. In seven seated postures, increased dead space breathing automatically increased V(t) (to 1.5 V(t)) to match volume between conditions and study the effects of posture independent of volume changes. %RC/V(t) (p<0.05), chest wall shape (p<0.05) and motion during breathing differed between postures. Compared to a reference posture, movement at the 9th rib lateral diameter increased in the thoracolumbar extension posture (p<0.008). In slumped posture movement at the AP diameters at T1 and axilla increased (p<0.00001). Rotation postures decreased movement in the lateral diameter at the axilla (p<0.0007). The data show that single plane changes in sitting posture alter three-dimensional ribcage configuration and chest wall kinematics during breathing, while maintaining constant respiratory function. Copyright 2010 Elsevier B.V. All rights reserved.

  6. Influence of left ventricular hypertrophy and geometry on diagnostic accuracy of wall motion and perfusion magnetic resonance during dobutamine stress.

    PubMed

    Gebker, Rolf; Mirelis, Jesus G; Jahnke, Cosima; Hucko, Thomas; Manka, Robert; Hamdan, Ashraf; Schnackenburg, Bernhard; Fleck, Eckart; Paetsch, Ingo

    2010-09-01

    The purpose of this study was to determine the influence of left ventricular (LV) hypertrophy and geometry on the diagnostic accuracy of wall motion and additional perfusion imaging during high-dose dobutamine/atropine stress magnetic resonance for the detection of coronary artery disease. Combined dobutamine stress magnetic resonance (DSMR)-wall motion and DSMR-perfusion imaging was performed in a single session in 187 patients scheduled for invasive coronary angiography. Patients were classified into 4 categories on the basis of LV mass (normal, ≤ 81 g/m(2) in men and ≤ 62 g/m(2) in women) and relative wall thickness (RWT) (normal, <0.45) as follows: normal geometry (normal mass, normal RWT), concentric remodeling (normal mass, increased RWT), concentric hypertrophy (increased mass, increased RWT), and eccentric hypertrophy (increased mass, normal RWT). Wall motion and perfusion images were interpreted sequentially, with observers blinded to other data. Significant coronary artery disease was defined as ≥ 70% stenosis. In patients with increased LV concentricity (defined by an RWT ≥ 0.45), sensitivity and accuracy of DSMR-wall motion were significantly reduced (63% and 73%, respectively; P<0.05) compared with patients without increased LV concentricity (90% and 88%, respectively; P<0.05). Although accuracy of DSMR-perfusion was higher than that of DSMR-wall motion in patients with concentric hypertrophy (82% versus 71%; P < 0.05), accuracy of DSMR-wall motion was superior to DSMR-perfusion (90% versus 85%; P < 0.05) in patients with eccentric hypertrophy. The accuracy of DSMR-wall motion is influenced by LV geometry. In patients with concentric remodeling and concentric hypertrophy, additional first-pass perfusion imaging during high-dose dobutamine stress improves the diagnostic accuracy for the detection of coronary artery disease.

  7. Ultrasound imaging transducer motion during clinical maneuvers: respiration, active straight leg raise test and abdominal drawing in.

    PubMed

    Whittaker, Jackie L; Warner, Martin B; Stokes, Maria J

    2010-08-01

    Clinical use of ultrasound imaging by physiotherapists is increasing; however, the clinical setting may be problematic due to variability inherent in the environment. As transducer motion interferes with accurate measurement, this study aimed to measure handheld transducer motion, relative to the pelvis, during a clinical simulation involving typical maneuvers employed in a physiotherapy assessment of the lumbopelvic region. Transducer motion about three axes and through one plane was measured (Vicon, Oxford, UK) on 12 participants during three clinical maneuvers at four abdominal imaging sites. Data were grouped and means used to determine discrepancies in transducer and pelvic motion for each imaging site/maneuver combination. None of the conditions produced large transducer motions relative to the pelvis and all findings were within previously established guidelines for acceptable amounts of transducer motion. These findings suggest that an ultrasound transducer can be held relatively stationary in a clinical setting, for the maneuvers tested. Copyright 2010 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  8. Spin-orbit-torque-induced magnetic domain wall motion in Ta/CoFe nanowires with sloped perpendicular magnetic anisotropy.

    PubMed

    Zhang, Yue; Luo, Shijiang; Yang, Xiaofei; Yang, Chang

    2017-05-17

    In materials with the gradient of magnetic anisotropy, spin-orbit-torque-induced magnetization behaviour has attracted attention because of its intriguing scientific principle and potential application. Most of the magnetization behaviours microscopically originate from magnetic domain wall motion, which can be precisely depicted using the standard cooperative coordinate method (CCM). However, the domain wall motion in materials with the gradient of magnetic anisotropy using the CCM remains lack of investigation. In this paper, by adopting CCM, we established a set of equations to quantitatively depict the spin-orbit-torque-induced motion of domain walls in a Ta/CoFe nanotrack with weak Dzyaloshinskii-Moriya interaction and magnetic anisotropy gradient. The equations were solved numerically, and the solutions are similar to those of a micromagnetic simulation. The results indicate that the enhanced anisotropy along the track acts as a barrier to inhibit the motion of the domain wall. In contrast, the domain wall can be pushed to move in a direction with reduced anisotropy, with the velocity being accelerated by more than twice compared with that for the constant anisotropy case. This substantial velocity manipulation by anisotropy engineering is important in designing novel magnetic information devices with high reading speeds.

  9. Atelectasis after free rectus transfer and abdominal wall reconstruction.

    PubMed

    Lo, Jamie O; Weber, Stephen M; Andersen, Peter E; Gross, Neil D; Gosselin, Marc; Wax, Mark K

    2008-10-01

    Atelectasis is commonly encountered in patients undergoing rectus abdominus tissue transfer. Primary closure of the anterior rectus sheath may contribute to this process. Augmentation of the closure with mesh may decrease the incidence of Atelectasis. In this retrospective review 32 patients with preoperative and postoperative augmentation were compared to 23 who had primary closure of the anterior rectus sheath. Augmentation consisted of acellular dermis (25) or mesh (7). Postoperative atelectasis was radiographically detected in: 91% (n=29) of augmented patients versus 83% (n=19) of primary closure patients. Major atelectasis in 41% (n=13) of augmented patients versus 61% (n=14) of primary closure patients p<.05. The incidence of atelectasis was independent of skin flap size and operative times. The use of acellular dermis or mesh to augment the abdominal wall appears to reduce the high incidence of postoperative atelectasis following rectus-free flap harvest. Copyright (c) 2008 Wiley Periodicals, Inc. Head Neck 2008.

  10. The risk of midgut volvulus in patients with abdominal wall defects: A multi-institutional study.

    PubMed

    Fawley, Jason A; Abdelhafeez, Abdelhafeez H; Schultz, Jessica A; Ertl, Allison; Cassidy, Laura D; Peter, Shawn St; Wagner, Amy J

    2017-01-01

    The management of malrotation in patients with congenital abdominal wall defects has varied among surgeons. We were interested in investigating the risk of midgut volvulus in patients with gastroschisis and omphalocele to help determine if these patients may benefit from undergoing a Ladd procedure. A retrospective chart review was performed for all patients managed at three institutions born between 1/1/2000 and 12/31/2008 with a diagnosis of gastroschisis or omphalocele. Patient charts were reviewed through 12/31/2012 for occurrence of midgut volvulus or need for second laparotomy. Of the 414 patients identified with abdominal wall defects, 299 patients (72%) had gastroschisis, and 115 patients (28%) had omphalocele. The mean gestational age at birth was 36.1±2.3weeks, and the mean birth weight was 2.57±0.7kg. There were a total of 8 (1.9%) cases of midgut volvulus: 3 (1.0%) patients with gastroschisis compared to 5 patients (4.4%) with omphalocele (p=0.04). Patients with omphalocele have a greater risk of developing midgut volvulus, and a Ladd procedure should be considered during definitive repair to mitigate these risks. III; retrospective comparative study. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Kilovoltage Imaging of Implanted Fiducials to Monitor Intrafraction Motion With Abdominal Compression During Stereotactic Body Radiation Therapy for Gastrointestinal Tumors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yorke, Ellen, E-mail: yorke@mskcc.org; Xiong, Ying; Han, Qian

    2016-07-01

    Purpose: To assess intrafraction respiratory motion using a commercial kilovoltage imaging system for abdominal tumor patients with implanted fiducials and breathing constrained by pneumatic compression during stereotactic body radiation therapy (SBRT). Methods and Materials: A pneumatic compression belt limited respiratory motion in 19 patients with radiopaque fiducials in or near their tumor during SBRT for abdominal tumors. Kilovoltage images were acquired at 5- to 6-second intervals during treatment using a commercial system. Intrafractional fiducial displacements were measured using in-house software. The dosimetric effect of the observed displacements was calculated for 3 sessions for each patient. Results: Intrafraction displacement patterns variedmore » between patients and between individual treatment sessions. Averaged over 19 patients, 73 sessions, 7.6% of craniocaudal displacements exceeded 0.5 cm, and 1.2% exceeded 0.75 cm. The calculated single-session dose to 95% of gross tumor volume differed from planned by an average of −1.2% (range, −11.1% to 4.8%) but only for 4 patients was the total 3-session calculated dose to 95% of gross tumor volume more than 3% different from planned. Conclusions: Our pneumatic compression limited intrafractional abdominal target motion, maintained target position established at setup, and was moderately effective in preserving coverage. Commercially available intrafractional imaging is useful for surveillance but can be made more effective and reliable.« less

  12. Kilovoltage Imaging of Implanted Fiducials to Monitor Intrafraction Motion With Abdominal Compression During Stereotactic Body Radiation Therapy for Gastrointestinal Tumors.

    PubMed

    Yorke, Ellen; Xiong, Ying; Han, Qian; Zhang, Pengpeng; Mageras, Gikas; Lovelock, Michael; Pham, Hai; Xiong, Jian-Ping; Goodman, Karyn A

    2016-07-01

    To assess intrafraction respiratory motion using a commercial kilovoltage imaging system for abdominal tumor patients with implanted fiducials and breathing constrained by pneumatic compression during stereotactic body radiation therapy (SBRT). A pneumatic compression belt limited respiratory motion in 19 patients with radiopaque fiducials in or near their tumor during SBRT for abdominal tumors. Kilovoltage images were acquired at 5- to 6-second intervals during treatment using a commercial system. Intrafractional fiducial displacements were measured using in-house software. The dosimetric effect of the observed displacements was calculated for 3 sessions for each patient. Intrafraction displacement patterns varied between patients and between individual treatment sessions. Averaged over 19 patients, 73 sessions, 7.6% of craniocaudal displacements exceeded 0.5 cm, and 1.2% exceeded 0.75 cm. The calculated single-session dose to 95% of gross tumor volume differed from planned by an average of -1.2% (range, -11.1% to 4.8%) but only for 4 patients was the total 3-session calculated dose to 95% of gross tumor volume more than 3% different from planned. Our pneumatic compression limited intrafractional abdominal target motion, maintained target position established at setup, and was moderately effective in preserving coverage. Commercially available intrafractional imaging is useful for surveillance but can be made more effective and reliable. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. 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

  14. 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.

  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.

  16. Feasibility of wall stress analysis of abdominal aortic aneurysms using three-dimensional ultrasound.

    PubMed

    Kok, Annette M; Nguyen, V Lai; Speelman, Lambert; Brands, Peter J; Schurink, Geert-Willem H; van de Vosse, Frans N; Lopata, Richard G P

    2015-05-01

    Abdominal aortic aneurysms (AAAs) are local dilations that can lead to a fatal hemorrhage when ruptured. Wall stress analysis of AAAs is a novel tool that has proven high potential to improve risk stratification. Currently, wall stress analysis of AAAs is based on computed tomography (CT) and magnetic resonance imaging; however, three-dimensional (3D) ultrasound (US) has great advantages over CT and magnetic resonance imaging in terms of costs, speed, and lack of radiation. In this study, the feasibility of 3D US as input for wall stress analysis is investigated. Second, 3D US-based wall stress analysis was compared with CT-based results. The 3D US and CT data were acquired in 12 patients (diameter, 35-90 mm). US data were segmented manually and compared with automatically acquired CT geometries by calculating the similarity index and Hausdorff distance. Wall stresses were simulated at P = 140 mm Hg and compared between both modalities. The similarity index of US vs CT was 0.75 to 0.91 (n = 12), with a median Hausdorff distance ranging from 4.8 to 13.9 mm, with the higher values found at the proximal and distal sides of the AAA. Wall stresses were in accordance with literature, and a good agreement was found between US- and CT-based median stresses and interquartile stresses, which was confirmed by Bland-Altman and regression analysis (n = 8). Wall stresses based on US were typically higher (+23%), caused by geometric irregularities due to the registration of several 3D volumes and manual segmentation. In future work, an automated US registration and segmentation approach is the essential point of improvement before pursuing large-scale patient studies. This study is a first step toward US-based wall stress analysis, which would be the modality of choice to monitor wall stress development over time because no ionizing radiation and contrast material are involved. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  17. Traumatic abdominal hernia complicated by necrotizing fasciitis.

    PubMed

    Martínez-Pérez, Aleix; Garrigós-Ortega, Gonzalo; Gómez-Abril, Segundo Ángel; Martí-Martínez, Eva; Torres-Sánchez, Teresa

    2014-11-01

    Necrotizing fasciitis is a critical illness involving skin and soft tissues, which may develop after blunt abdominal trauma causing abdominal wall hernia and representing a great challenge for physicians. A 52-year-old man was brought to the emergency department after a road accident, presenting blunt abdominal trauma with a large non-reducible mass in the lower-right abdomen. A first, CT showed abdominal hernia without signs of complication. Three hours after ICU admission, he developed hemodynamic instability. Therefore, a new CT scan was requested, showing signs of hernia complication. He was moved to the operating room where a complete transversal section of an ileal loop was identified. Five hours after surgery, he presented a new episode of hemodynamic instability with signs of skin and soft tissue infection. Due to the high clinical suspicion of necrotizing fasciitis development, wide debridement was performed. Following traumatic abdominal wall hernia (TAWH), patients can present unsuspected injuries in abdominal organs. Helical CT can be falsely negative in the early moments, leading to misdiagnosis. Necrotizing fasciitis is a potentially fatal infection and, consequently, resuscitation measures, wide-spectrum antibiotics, and early surgical debridement are required. This type of fasciitis can develop after blunt abdominal trauma following wall hernia without skin disruption.

  18. [Vesico-cutaneous fistula revealing abdominal wall malakoplakia accompanied by Boeck's sarcoidosis].

    PubMed

    Knausz, József; Lipták, József; Andrásovszky, Zsolt; Baranyay, Ferenc

    2010-02-07

    Malakoplakia is an acquired granulomatous disorder first described by Michaelis and Gutmann in 1902. The pathogenesis of malakoplakia is hardly known, but it thought to be secondary to an acquired bactericidal defect in macrophages occurring mostly in immunosuppressed patients. 63-year-old female patient had been treated with methylprednisolone for ten years, because of pulmonary sarcoidosis. For six month, recurrent abdominal abscess and vesico-cutaneous fistula developed. Histological examination proved malakoplakia, and Escherichia coli was detected in the abscess cavity. Hematoxyline eosin staining, periodic acid-Schiff, Berlin-blue and Kossa reactions were performed. Microscopically malakoplakia consists of mainly macrophages, known as von Hansemann cells with scattered targetoid intracytoplasmic inclusions known as Michaelis-Gutmann bodies. In our presented case, after urological-surgical intervention and antibiotic therapy, the patient became free from complaints and symptoms. Malakoplakia has been described in numerous anatomic locations, mainly in the urogenital tract. Malakoplakia may be complicated with fistulas in different locations: vesico-coccygeal, rectoprostatic, anorectal fistulas have been were reported in the literature, while 6 cases of malakoplakia with Boeck's sarcoidosis are published. In the presented case sarcoidosis and the 10-year immunosuppressive treatment with methylprednisolone might have been in the background of abdominal wall malakoplakia, complicated by vesico-cutaneous fistula. The patient was successfully treated with surgery and the followed antibiotic therapy.

  19. Anaesthetic injection versus ischemic compression for the pain relief of abdominal wall trigger points in women with chronic pelvic pain.

    PubMed

    Montenegro, Mary L L S; Braz, Carolina A; Rosa-e-Silva, Julio C; Candido-dos-Reis, Francisco J; Nogueira, Antonio A; Poli-Neto, Omero B

    2015-12-01

    Chronic pelvic pain is a common condition among women, and 10 to 30 % of causes originate from the abdominal wall, and are associated with trigger points. Although little is known about their pathophysiology, variable methods have been practiced clinically. The purpose of this study was to evaluate the efficacy of local anaesthetic injections versus ischemic compression via physical therapy for pain relief of abdominal wall trigger points in women with chronic pelvic pain. We conducted a parallel group randomized trial including 30 women with chronic pelvic pain with abdominal wall trigger points. Subjects were randomly assigned to one of two intervention groups. One group received an injection of 2 mL 0.5 % lidocaine without a vasoconstrictor into a trigger point. In the other group, ischemic compression via physical therapy was administered at the trigger points three times, with each session lasting for 60 s, and a rest period of 30 s between applications. Both treatments were administered during one weekly session for four weeks. Our primary outcomes were satisfactory clinical response rates and percentages of pain relief. Our secondary outcomes are pain threshold and tolerance at the trigger points. All subjects were evaluated at baseline and 1, 4, and 12 weeks after the interventions. The study was conducted at a tertiary hospital that was associated with a university providing assistance predominantly to working class women who were treated by the public health system. Clinical response rates and pain relief were significantly better at 1, 4, and 12 weeks for those receiving local anaesthetic injections than ischemic compression via physical therapy. The pain relief of women treated with local anaesthetic injections progressively improved at 1, 4, and 12 weeks after intervention. In contrast, women treated with ischemic compression did not show considerable changes in pain relief after intervention. In the local anaesthetic injection group, pain threshold

  20. Lymphedema of the Transplanted Kidney and Abdominal Wall with Ipsilateral Pleural Effusion Following Kidney Biopsy in a Patient Treated with Sirolimus: A Case Report and Review of the Literature

    PubMed Central

    Rashid-Farokhi, Farin; Afshar, Hale

    2017-01-01

    Patient: Female, 32 Final Diagnosis: Sirolimus induced congestion of kidney and overlying abdominal wall Symptoms: Abdominal pain • abdominal swelling • dyspnea Medication: — Clinical Procedure: Improvement of symptoms with drug withdrawal Specialty: Nephrology Objective: Adverse events of drug therapy Background: Sirolimus is a mammalian target of rapamycin (mTOR) inhibitor, which is used in immunosuppressive treatment regimens in organ transplant recipients. Although mTOR inhibitors are well tolerated, their adverse effects have been reported. Sirolimus treatment in transplant recipients has been reported to be associated with lymphedema of the skin and subcutaneous tissues, and with pleural effusion, but edema of internal organs and organomegaly have not been previously reported. A case is presented lymphedema of the transplanted kidney and abdominal wall with ipsilateral pleural effusion following kidney biopsy in a patient treated with sirolimus. Case Report: A 32-year-old woman with a history of end-stage renal disease of unknown etiology had undergone right renal transplantation from an unrelated living donor, eight years previously. She was referred to our hospital with dyspnea, localized abdominal pain, and swelling of the transplanted kidney. The symptoms appeared following a kidney biopsy and the replacement of cyclosporin with sirolimus four months previously. On examination, she had localized swelling of the abdominal wall overlying the transplanted kidney, and a right pleural effusion. Hydronephrosis and nephrotic syndrome were excluded as causes of kidney enlargement. Following the withdrawal of sirolimus therapy her symptoms resolved within three months. Conclusions: A case is described of lymphedema of the transplanted kidney and abdominal wall with ipsilateral pleural effusion following kidney biopsy attributed to her change in anti-rejection therapy to sirolimus. This case report should raise awareness of this unusual complication of

  1. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Mechanisms of postprandial abdominal bloating and distension in functional dyspepsia.

    PubMed

    Burri, Emanuel; Barba, Elizabeth; Huaman, Jose Walter; Cisternas, Daniel; Accarino, Anna; Soldevilla, Alfredo; Malagelada, Juan-R; Azpiroz, Fernando

    2014-03-01

    Patients with irritable bowel syndrome and abdominal bloating exhibit abnormal responses of the abdominal wall to colonic gas loads. We hypothesised that in patients with postprandial bloating, ingestion of a meal triggers comparable abdominal wall dyssynergia. Our aim was to characterise abdominal accommodation to a meal in patients with postprandial bloating. A test meal (0.8 kcal/ml nutrients plus 27 g/litre polyethylenglycol 4000) was administered at 50 ml/min as long as tolerated in 10 patients with postprandial bloating (fulfilling Rome III criteria for postprandial distress syndrome) and 12 healthy subjects, while electromyographic (EMG) responses of the anterior wall (upper and lower rectus, external and internal oblique via bipolar surface electrodes) and the diaphragm (via six ring electrodes over an oesophageal tube in the hiatus) were measured. Means +/- SD were calculated. Healthy subjects tolerated a meal volume of 913±308 ml; normal abdominal wall accommodation to the meal consisted of diaphragmatic relaxation (EMG activity decreased by 15±6%) and a compensatory contraction (25±9% increase) of the upper abdominal wall muscles (upper rectus and external oblique), with no changes in the lower anterior muscles (lower rectus and internal oblique). Patients tolerated lower volume loads (604±310 ml; p=0.030 vs healthy subjects) and developed a paradoxical response, that is, diaphragmatic contraction (14±3% EMG increment; p<0.01 vs healthy subjects) and upper anterior wall relaxation (9±4% inhibition; p<0.01 vs healthy subjects). In functional dyspepsia, postprandial abdominal distension is produced by an abnormal viscerosomatic response to meal ingestion that alters normal abdominal accommodation.

  3. Coordination Between Ribs Motion and Thoracoabdominal Volumes in Swimmers During Respiratory Maneuvers

    PubMed Central

    Sarro, Karine J.; Silvatti, Amanda P.; Barros, Ricardo M. L.

    2008-01-01

    This work aimed to verify if swimmers present better chest wall coordination during breathing than healthy non-athletes analyzing the correlation between ribs motion and the variation of thoracoabdominal volumes. The results of two up-to-date methods based on videogrammetry were correlated in this study. The first one measured the volumes of 4 separate compartments of the chest wall (superior thorax, inferior thorax, superior abdomen and inferior abdomen) as a function of time. The second calculated the rotation angle of the 2nd to the 10th ribs around the quasi-transversal axis also in function of time. The chest wall was represented by 53 markers, attached to the ribs, vertebrae, thorax and abdomen of 15 male swimmers and of 15 non- athletes. A kinematical analysis system equipped with 6 digital video cameras (60Hz) was used to obtain the 3D coordinates of the markers. Correlating the curves of ribs rotation angles with the curves of the separate volumes, swimmers presented higher values than non-athletes when the superior and inferior abdomen were considered and the highest correlation values were found in swimmers for the inferior thorax. These results suggest a better coordination between ribs motion and thoracoabdominal volumes in swimmers, indicating the prevalent and coordinated action of the diaphragm and abdominal muscles to inflate and deflate the chest wall. The results further suggest that swimming practice leads to the formation of an optimized breathing pattern and can partially explain the higher lung volumes found in these athletes reported in literature. Key pointsThe study revealed that swimmers present higher correlation between the ribs motion and the variation of abdominal volumes than non-swimmers, suggesting that swimming practice might lead to the formation of an optimized breathing pattern, increasing the coordination between the thoracoabdominal volumes and the ribs motion.No previous work was found in the literature reporting this

  4. Short-term effect of volume recruitment-derecruitment manoeuvre on chest-wall motion in Duchenne muscular dystrophy.

    PubMed

    Meric, Henri; Falaize, Line; Pradon, Didier; Lacombe, Matthieu; Petitjean, Michel; Orlikowski, David; Prigent, Hélène; Lofaso, Frédéric

    2017-05-01

    Because progressive respiratory muscle weakness leads to decreased chest-wall motion with eventual ribcage stiffening, the purpose was to compare vital capacity (VC) and contributions of chest-wall compartments before and after volume recruitment-derecruitment manoeuvres (VRDM) in Duchenne muscular dystrophy (DMD). We studied nine patients with DMD and VC lower than 30% of predicted. VRDM was performed using 15 insufflations-exsufflations of +30 to -30 cmH 2 O. VC and three-dimensional chest-wall motion were measured, as well as oxygen saturation, transcutaneous partial pressure of carbon dioxide and the rapid shallow breathing index (respiratory rate/tidal volume) before (baseline) and immediately and 1 hour after VRDM. VC increased significantly immediately after VRDM (108% ± 7% of baseline, p = 0.018) but returned to baseline within 1 hour, and the rapid shallow breathing index increased significantly. The non-dominant side systematically increased immediately after VRDM ( p = 0.0077), and in the six patients with abnormal breathing asymmetry (difference >10% of VC) at baseline, this asymmetry was corrected immediately and/or 1 hour after VRDM. VRDM improved VC and reduced chest-wall motion asymmetry, but this beneficial effect waned rapidly with respiratory muscle fatigue, suggesting that VRDM may need to be repeated during the day to produce lasting benefits.

  5. Processive motions of MreB micro-filaments coordinate cell wall growth

    NASA Astrophysics Data System (ADS)

    Garner, Ethan

    2012-02-01

    Rod-shaped bacteria elongate by the action of cell-wall synthesis complexes linked to underlying dynamic MreB filaments, but how these proteins function to allow continued elongation as a rod remains unknown. To understand how the movement of these filaments relates to cell wall synthesis, we characterized the dynamics of MreB and the cell wall elongation machinery using high-resolution particle tracking in Bacillus subtilis. We found that both MreB and the elongation machinery move in linear paths across the cell, moving at similar rates (˜20nm / second) and angles to the cell body, suggesting they function as single complexes. These proteins move circumferentially around the cell, principally perpendicular to its length. We find that the motions of these complexes are independent, as they can pause and reverse,and also as nearby complexes move independently in both directions across one surface of the cell. Inhibition of cell wall synthesis with antibiotics or depletions in the cell wall synthesis machinery blocked MreB movement, suggesting that the cell wall synthetic machinery is the motor in this system. We propose that bacteria elongate by the uncoordinated, circumferential movements of synthetic complexes that span the plasma membrane and insert radial hoops of new peptidoglycan during their transit.

  6. Histopathological analysis of cellular localization of cathepsins in abdominal aortic aneurysm wall.

    PubMed

    Lohoefer, Fabian; Reeps, Christian; Lipp, Christina; Rudelius, Martina; Zimmermann, Alexander; Ockert, Stefan; Eckstein, Hans-Henning; Pelisek, Jaroslav

    2012-08-01

    An important feature of abdominal aortic aneurysm (AAA) is the destruction of vessel wall, especially elastin and collagen. Besides matrix metalloproteinases, cathepsins are the most potent elastolytic enzymes. The expression of cathepsins with known elastolytic and collagenolytic activities in the individual cells within AAA has not yet been determined. The vessel wall of 32 AAA patients and 10 organ donors was analysed by immunohistochemistry for expression of cathepsins B, D, K, L and S, and cystatin C in all cells localized within AAA. Luminal endothelial cells (ECs) of AAA were positive for cathepsin D and partially for cathepsins B, K and S. Endothelial cells of the neovessels and smooth muscle cells in the media were positive for all cathepsins tested, especially for cathepsin B. In the inflammatory infiltrate all cathepsins were expressed in the following pattern: B > D = S > K = L. Macrophages showed the highest staining intensity for all cathepsins. Furthermore, weak overall expression of cystatin C was observed in all the cells localized in the AAA with the exception of the ECs. There is markedly increased expression of the various cathepsins within the AAA wall compared to healthy aorta. Our data are broadly consistent with a role for cathepsins in AAA; and demonstrate expression of cathepsins D, B and S in phagocytic cells in the inflammatory infiltrate; and also may reveal a role for cathepsin B in lymphocytes. © 2012 The Authors. International Journal of Experimental Pathology © 2012 International Journal of Experimental Pathology.

  7. Microwave fields driven domain wall motions in antiferromagnetic nanowires

    NASA Astrophysics Data System (ADS)

    Chen, Z. Y.; Yan, Z. R.; Zhang, Y. L.; Qin, M. H.; Fan, Z.; Lu, X. B.; Gao, X. S.; Liu, J.-M.

    2018-06-01

    In this work, we study the microwave field driven domain wall (DW) motion in an antiferromagnetic nanowire, using the numerical calculations based on a classical Heisenberg spin model with the biaxial magnetic anisotropy. We show that a proper combination of a static magnetic field plus an oscillating field perpendicular to the nanowire axis is sufficient to drive the DW propagation along the nanowire. More importantly, the drift velocity at the resonance frequency is comparable to that induced by temperature gradients, suggesting that microwave field can be a very promising tool to control DW motions in antiferromagnetic nanostructures. The dependences of resonance frequency and drift velocity on the static and oscillating fields, the axial anisotropy, and the damping constant are discussed in details. Furthermore, the optimal orientations of the field are also numerically determined and explained. This work provides useful information for the spin dynamics in antiferromagnetic nanostructures for spintronics applications.

  8. [Abdominal catastrophe--abdominal wall defect associated with gastrointestinal fistula--strategy of therapy].

    PubMed

    Chobola, M; Sobotka, L; Ferko, A; Oberreiter, M; Kaska, M; Motycka, V; Páral, J; Mottl, R

    2010-11-01

    Wound dehiscence complicated by gastrointestinal (GI) fistula to belong ,,abdominal catastrophe". Therapy is prolonged and connected with high morbidity and mortality rate. In the period from October 2006 to July 2009 we performed 12 reconstructive surgical procedures on gastrointestinal tract in patients with abdominal catastrophe. Treatment of 12 consecutive patients (9 men, 3 women) was managed according to a standardize protocol. The protocol consists of treatment of septic complications, optimisation of nutritional state, special wound procedures, diagnosis of gastrointestinal fistulas and GI tract, timing of surgical procedures, reconstruction of GI tract and postoperative care. Reconstructive surgery of GI tract was successful on 11 patients. One patient developed recurrence of early GI fistula. In four patients we let open abdomen to heal per secundam. We observed no deaths after operation. With regard to complex character of therapy of abdominal catastrophe there is a need of multidisciplinary approach. Considering long-lasting and expensive therapy there is logical step to concentrate these patients into special centres which are experienced, equipped and their staff is trained in treatment of such a seriously impaired patients.

  9. Correlation between the viscoelastic heterogeneity and the domain wall motion of Fe-based metallic glass

    NASA Astrophysics Data System (ADS)

    Ouyang, S.; Song, L. J.; Liu, Y. H.; Huo, J. T.; Wang, J. Q.; Xu, W.; Li, J. L.; Wang, C. T.; Wang, X. M.; Li, R. W.

    2018-06-01

    The soft magnetic properties of Fe-based metallic glasses are reduced significantly by external and residual stresses, e.g., the susceptibility decreases and coercivity increases, which limits their application severely. Unraveling the micromechanism of how the stress influences the soft magnetic properties is of great help for enhancing the performance of Fe-based metallic glasses. In this work, we investigate the effect of viscoelastic heterogeneity on the motion of magnetic domain wall surrounding nanoindentations. Compared to the matrix, dissipation of the viscoelastic heterogeneity increases toward the nanoindentation. Meanwhile, the motion of domain wall under external magnetic field becomes more difficult toward the nanoindentations. A correlation between the viscoelastic dissipation and the moving ability of magnetic domain walls is observed, which can be well fitted using magnetoelastic coupling theory. This suggests that manipulating the microscale viscoelastic heterogeneity is probably a helpful strategy for enhancing the soft magnetic properties of metallic glasses.

  10. Challenges in the repair of large abdominal wall hernias in Nigeria: review of available options in resource limited environments.

    PubMed

    Ezeome, E R; Nwajiobi, C E

    2010-06-01

    To evaluate the challenges and outcome of management of large abdominal wall hernias in a resource limited environment and highlight the options available to surgeons in similar conditions. A review of prospectively collected data on large abdominal wall hernias managed between 2003 and 2009. University of Nigeria Teaching Hospital, Enugu, Nigeria and surrounding hospitals. Patients with hernias more than 4 cm in their largest diameter, patients with closely sited multiple hernias or failed previous repairs and in whom the surgeon considers direct repair inappropriate. Demographics of patients with large hernias, methods of hernia repair, recurrences, early and late complications following the repair. There were 41 patients, comprising 28 females and 13 males with ages 14 - 73 years. Most (53.7%) were incisional hernias. Gynecological surgeries (66.7%) were the most common initiating surgeries. Fifteen of the patients (36.6%) have had failed previous repairs, 41.5% were obese, five patients presented with intestinal obstruction. Thirty nine of the hernias were repaired with prolene mesh, one with composite mesh and one by danning technique. Most of the patients had extra peritoneal mesh placement. Three patients needed ventilator support. After a mean follow up of 18.6 months, there was a single failed repair. Two post op deaths were related to respiratory distress. There were 12 wound infection and 8 superficial wound dehiscence, all of which except one resolved with dressing. One reoperation was done following mesh infection and extrusion. Large abdominal wall hernia repair in resource limited environments present several challenges with wound infection and respiratory distress being the most notable. Surgeons who embark on it in these environments must be prepared t o secure the proper tissue replacement materials and have adequate ventilation support.

  11. Assessment of dyssynchronous wall motion during acute myocardial ischemia using velocity vector imaging.

    PubMed

    Masuda, Kasumi; Asanuma, Toshihiko; Taniguchi, Asuka; Uranishi, Ayumi; Ishikura, Fuminobu; Beppu, Shintaro

    2008-03-01

    The purpose of this study was to investigate the diagnostic value of velocity vector imaging (VVI) for detecting acute myocardial ischemia and whether VVI can accurately demonstrate the spatial extent of ischemic risk area. Using a tracking algorithm, VVI can display velocity vectors of regional wall motion overlaid onto the B-mode image and allows the quantitative assessment of myocardial mechanics. However, its efficacy for diagnosing myocardial ischemia has not been evaluated. In 18 dogs with flow-limiting stenosis and/or total occlusion of the coronary artery, peak systolic radial velocity (V(SYS)), radial velocity at mitral valve opening (V(MVO)), peak systolic radial strain, and the percent change in wall thickening (%WT) were measured in the normal and risk areas and compared to those at baseline. Sensitivity and specificity for detecting the stenosis and occlusion were analyzed in each parameter. The area of inward velocity vectors at mitral valve opening (MVO) detected by VVI was compared to the risk area derived from real-time myocardial contrast echocardiography (MCE). Twelve image clips were randomly selected from the baseline, stenosis, and occlusions to determine the intra- and inter-observer agreement for the VVI parameters. The left circumflex coronary flow was reduced by 44.3 +/- 9.0% during stenosis and completely interrupted during occlusion. During coronary artery occlusion, inward motion at MVO was observed in the risk area. Percent WT, peak systolic radial strain, V(SYS), and V(MVO) changed significantly from values at baseline. During stenosis, %WT, peak systolic radial strain, and V(SYS) did not differ from those at baseline; however, V(MVO) was significantly increased (-0.12 +/- 0.60 cm/s vs. -0.96 +/- 0.55 cm/s, p = 0.015). Sensitivity and specificity of V(MVO) for detecting ischemia were superior to those of other parameters. The spatial extent of inward velocity vectors at MVO correlated well with that of the risk area derived from MCE

  12. Dynamic radionuclide determination of regional left ventricular wall motion using a new digital imaging device

    NASA Technical Reports Server (NTRS)

    Steele, P.; Kirch, D.

    1975-01-01

    In 47 men with arteriographically defined coronary artery disease comparative studies of left ventricular ejection fraction and segmental wall motion were made with radionuclide data obtained from the image intensifier camera computer system and with contrast cineventriculography. The radionuclide data was digitized and the images corresponding to left ventricular end-diastole and end-systole were identified from the left ventricular time-activity curve. The left ventricular end-diastolic and end-systolic images were subtracted to form a silhouette difference image which described wall motion of the anterior and inferior left ventricular segments. The image intensifier camera allows manipulation of dynamically acquired radionuclide data because of the high count rate and consequently improved resolution of the left ventricular image.

  13. Perforated peptic ulcer associated with abdominal compartment syndrome.

    PubMed

    Lynn, Jiun-Jen; Weng, Yi-Ming; Weng, Chia-Sui

    2008-11-01

    Abdominal compartment syndrome (ACS) is defined as an increased intra-abdominal pressure with adverse physiologic consequences. Abdominal compartment syndrome caused by perforated peptic ulcer is rare owing to early diagnosis and management. Delayed recognition of perforated peptic ulcer with pneumoperitoneum, bowel distension, and decreased abdominal wall compliance can make up a vicious circle and lead to ACS. We report a case of perforated peptic ulcer associated with ACS. A 74-year-old man with old stroke and dementia history was found to have distended abdomen, edema of bilateral legs, and cyanosis. Laboratory tests revealed deterioration of liver and kidney function. Abdominal compartment syndrome was suspected, and image study was arranged to find the cause. The study showed pneumoperitoneum, contrast stasis in heart with decreased caliber of vessels below the abdominal aortic level, and diffuse lymphedema at the abdominal walls. Emergent laparotomy was performed. Perforated peptic ulcer was noted and the gastrorrhaphy was done. The symptoms, and liver and kidney function improved right after emergent operation.

  14. Spatio-temporal characteristics of large scale motions in a turbulent boundary layer from direct wall shear stress measurement

    NASA Astrophysics Data System (ADS)

    Pabon, Rommel; Barnard, Casey; Ukeiley, Lawrence; Sheplak, Mark

    2016-11-01

    Particle image velocimetry (PIV) and fluctuating wall shear stress experiments were performed on a flat plate turbulent boundary layer (TBL) under zero pressure gradient conditions. The fluctuating wall shear stress was measured using a microelectromechanical 1mm × 1mm floating element capacitive shear stress sensor (CSSS) developed at the University of Florida. The experiments elucidated the imprint of the organized motions in a TBL on the wall shear stress through its direct measurement. Spatial autocorrelation of the streamwise velocity from the PIV snapshots revealed large scale motions that scale on the order of boundary layer thickness. However, the captured inclination angle was lower than that determined using the classic method by means of wall shear stress and hot-wire anemometry (HWA) temporal cross-correlations and a frozen field hypothesis using a convection velocity. The current study suggests the large size of these motions begins to degrade the applicability of the frozen field hypothesis for the time resolved HWA experiments. The simultaneous PIV and CSSS measurements are also used for spatial reconstruction of the velocity field during conditionally sampled intense wall shear stress events. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1315138.

  15. Motion and volumetric change as demonstrated by 4DCT: The effects of abdominal compression on the GTV, lungs, and heart in lung cancer patients.

    PubMed

    Rasheed, Abdullah; Jabbour, Salma K; Rosenberg, Stephen; Patel, Ajay; Goyal, Sharad; Haffty, Bruce G; Yue, Ning J; Khan, Alvin

    2016-01-01

    Lung tumors move during respiration, complicating radiation therapy. The abdominal compression plate (ACP) is thought to reduce respiratory motion. This study quantifies ACP efficacy on respiratory-induced motion by using 4-dimensional computed tomography to evaluate volume and displacement changes of the heart, lungs, and tumor with and without ACP. Lung cancer patients (n = 17) received 4-dimensional computed tomography simulations (10 computed tomography scans from 0% to 90% breathing phases) with and without ACP under maximally tolerated diaphragmatic pressure. Gross tumor volume (GTV), heart, and lungs were contoured in treatment planning software for each phase. Structures were exported for analysis. For each phase, with and without ACP, tumor and organ absolute centroid range of motion and volume were calculated. ACP did not significantly affect GTV, heart, or lung motion on the sample as a whole, but instead demonstrated patient-specific results. ACP reduced GTV motion in 3 (17.6%; 3 upper lobe tumors) by 2.9 mm (P < .01), increased motion in 5 (29.4%; 3 upper lobe tumors, 1 middle lobe, 1 lower lobe) by 1.9 mm (P < .03), and did not significantly change 9. Of the 3 patients exhibiting significantly decreased GTV motion, GTV, heart, and lung range of motion was 7.4 mm, 11.8 mm, and 11.9 mm, respectively, without compression and 4.5 mm, 8.4 mm, and 10.9 mm, respectively, with compression. Averaged across the sample, ACP did not exhibit any axis-specific effect. ACP efficacy was patient-specific, possibly because of pre-existing factors including chronic obstructive pulmonary disease severity, chest wall elasticity, tumor location, and patient comfort. Tumor lobe location does not predetermine compression efficacy; therefore, patients should be simulated with and without ACP, regardless of tumor location. GTV motion seems most important in determining suitability for compression. Alternative motion control should be considered in patients not benefited by

  16. [A commonly seen cause of abdominal pain: abdominal cutaneous nerve entrapment syndrome].

    PubMed

    Solmaz, Ilker; Talay, Mustafa; Tekindur, Şükrü; Kurt, Ercan

    2012-01-01

    Although abdominal cutaneous nerve entrapment syndrome (ACNES) is accepted as a rare condition, it is a syndrome that should be diagnosed more commonly when the clinical signs cannot explain the cause of abdominal pain. Abdominal pain is commonly considered by physicians to be based on intra-abdominal causes. Consequently, redundant tests and consultations are requested for these patients, and unnecessary surgical procedures may be applied. Patients with this type of pain are consulted to many clinics, and because their definitive diagnoses cannot be achieved, they are assessed as psychiatric patients. Actually, a common cause of abdominal wall pain is nerve entrapment on the lateral edge of the rectus abdominis muscle. In this paper, we would like to share information about the diagnosis and treatment of a patient who, prior to presenting to us, had applied to different clinics for chronic abdominal pain and had undergone many tests and consultations; abdominal surgery was eventually decided.

  17. Spinmotive force due to domain wall motion in high field regime

    NASA Astrophysics Data System (ADS)

    Ieda, Jun'ichi; Yamane, Yuta; Maekawa, Sadamichi

    2012-02-01

    Spinmotive force associated with a moving vortex domain wall is investigated numerically. Dynamics of magnetization textures such as a domain wall exerts a non-conservative spin-force on conduction electrons [1], offering a new concept of magnetic devices [2]. This spinmotive force in permalloy nanowires has been detected by voltage measurement [3] where magnitude of the signal is limited less than 500 nV. Theoretically it is suggested that the spinmotive force signal increases as a function of external magnetic fields. At higher magnetic fields, however, the wall propagation mode becomes rather chaotic involving transformations of the wall structure and it remains to be seen how the spinmotive force appears. Numerical simulations show that the spinmotive force scales with the field even in a field range where the wall motion is no longer associated coherent precession. This feature has been tested in a recent experiment [4]. Further enhancement of the spinmotive force is explored by designing ferromagnetic nanostructures [5] and materials. [1] S. Barnes and S. Maekawa, PRL (2007). [2] S. Barnes, J. Ieda, and S. Maekawa, APL (2006). [3] S. A. Yang et al., PRL (2009). [4] M. Hayashi, J. Ieda et al., submitted. [5] Y. Yamane, J. Ieda et al., APEX (2011).

  18. Abdomino-phrenic dyssynergia in patients with abdominal bloating and distension.

    PubMed

    Villoria, Albert; Azpiroz, Fernando; Burri, Emanuel; Cisternas, Daniel; Soldevilla, Alfredo; Malagelada, Juan-R

    2011-05-01

    The abdomen normally accommodates intra-abdominal volume increments. Patients complaining of abdominal distension exhibit abnormal accommodation of colonic gas loads (defective contraction and excessive protrusion of the anterior wall). However, abdominal imaging demonstrated diaphragmatic descent during spontaneous episodes of bloating in patients with functional gut disorders. We aimed to establish the role of the diaphragm in abdominal distension. In 20 patients complaining of abdominal bloating and 15 healthy subjects, we increased the volume of the abdominal cavity with a colonic gas load, while measuring abdominal girth and electromyographic activity of the anterior abdominal muscles and of the diaphragm. In healthy subjects, the colonic gas load increased girth, relaxed the diaphragm, and increased anterior wall tone. With the same gas load, patients developed significantly more abdominal distension; this was associated with paradoxical contraction of the diaphragm and relaxation of the internal oblique muscle. In this experimental provocation model, abnormal accommodation of the diaphragm is involved in abdominal distension.

  19. Abdominal Pain Syndrome

    MedlinePlus

    ... blood clots to the lungs) Abdominal or chest wall pain: Shingles (herpes zoster infection) Costochondritis (inflammation of ... or tumors), fat (evidence of impaired digestion and absorption of food), and the presence of germs. X- ...

  20. Evaluation of kidney motion and target localization in abdominal SBRT patients

    PubMed Central

    Sonier, Marcus; Chu, William; Lalani, Nafisha; Erler, Darby; Cheung, Patrick

    2016-01-01

    The purpose of this study was to evaluate bilateral kidney and target translational/rotational intrafraction motion during stereotactic body radiation therapy treatment delivery of primary renal cell carcinoma and oligometastatic adrenal lesions for patients immobilized in the Elekta BodyFIX system. Bilateral kidney motion was assessed at midplane for 30 patients immobilized in a full‐body dual‐vacuum‐cushion system with two patients immobilized via abdominal compression. Intrafraction motion was assessed for 15 patients using kilovoltage cone‐beam computed tomography (kV‐CBCT) datasets (n=151) correlated to the planning CT. Patient positioning was corrected for translational and rotational misalignments using a robotic couch in six degrees of freedom if setup errors exceeded 1 mm and 1°. Absolute bilateral kidney motion between inhale and exhale 4D CT imaging phases for left–right (LR), superior–inferior (SI), and anterior–posterior (AP) directions was 1.51±1.00mm,8.10±4.33mm, and 3.08±2.11mm, respectively. Residual setup error determined across CBCT type (pretreatment, intrafraction, and post‐treatment) for x (LR), y (SI), and z (AP) translations was 0.63±0.74mm,1.08±1.38mm, and 0.70±1.00mm; while for x (pitch), y (roll), and z (yaw) rotations was 0.24±0.39°,0.19±0.34°, and 0.26±0.43°, respectively. Targets were localized to within 2.1 mm and 0.8° 95% of the time. The frequency of misalignments in the y direction was significant (p<0.05) when compared to the x and z directions with no significant difference in translations between IMRT and VMAT. This technique is robust using BodyFIX for patient immobilization and reproducible localization of kidney and adrenal targets and daily CBCT image guidance for correction of positional errors to maintain treatment accuracy. PACS number(s): 87.55.‐x, 87.56.‐v, 87.56.Da PMID:27929514

  1. Aortic Wall Inflammation Predicts Abdominal Aortic Aneurysm Expansion, Rupture, and Need for Surgical Repair.

    PubMed

    2017-08-29

    Ultrasmall superparamagnetic particles of iron oxide (USPIO) detect cellular inflammation on magnetic resonance imaging (MRI). In patients with abdominal aortic aneurysm, we assessed whether USPIO-enhanced MRI can predict aneurysm growth rates and clinical outcomes. In a prospective multicenter open-label cohort study, 342 patients with abdominal aortic aneurysm (diameter ≥40 mm) were classified by the presence of USPIO enhancement and were monitored with serial ultrasound and clinical follow-up for ≥2 years. The primary end point was the composite of aneurysm rupture or repair. Participants (85% male, 73.1±7.2 years) had a baseline aneurysm diameter of 49.6±7.7 mm, and USPIO enhancement was identified in 146 (42.7%) participants, absent in 191 (55.8%), and indeterminant in 5 (1.5%). During follow-up (1005±280 days), 17 (5.0%) abdominal aortic aneurysm ruptures, 126 (36.8%) abdominal aortic aneurysm repairs, and 48 (14.0%) deaths occurred. Compared with those without uptake, patients with USPIO enhancement have increased rates of aneurysm expansion (3.1±2.5 versus 2.5±2.4 mm/year, P =0.0424), although this was not independent of current smoking habit ( P =0.1993). Patients with USPIO enhancement had higher rates of aneurysm rupture or repair (47.3% versus 35.6%; 95% confidence intervals, 1.1-22.2; P =0.0308). This finding was similar for each component of rupture (6.8% versus 3.7%, P =0.1857) or repair (41.8% versus 32.5%, P =0.0782). USPIO enhancement was associated with reduced event-free survival for aneurysm rupture or repair ( P =0.0275), all-cause mortality ( P =0.0635), and aneurysm-related mortality ( P =0.0590). Baseline abdominal aortic aneurysm diameter ( P <0.0001) and current smoking habit ( P =0.0446) also predicted the primary outcome, and the addition of USPIO enhancement to the multivariate model did not improve event prediction (c-statistic, 0.7935-0.7936). USPIO-enhanced MRI is a novel approach to the identification of aortic wall

  2. Aortic Wall Inflammation Predicts Abdominal Aortic Aneurysm Expansion, Rupture, and Need for Surgical Repair

    PubMed Central

    2017-01-01

    identification of aortic wall cellular inflammation in patients with abdominal aortic aneurysms and predicts the rate of aneurysm growth and clinical outcome. However, it does not provide independent prediction of aneurysm expansion or clinical outcomes in a model incorporating known clinical risk factors. Clinical Trial Registration: URL: http://www.isrctn.com. Unique identifier: ISRCTN76413758. PMID:28720724

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eccles, Cynthia L.; Patel, Ritesh; Simeonov, Anna K.

    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 30-60more » 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.« less

  4. A rare case of severe third degree friction burns and large Morel-Lavallee lesion of the abdominal wall.

    PubMed

    Brown, Darnell J; Lu, Kuo Jung G; Chang, Kristina; Levin, Jennifer; Schulz, John T; Goverman, Jeremy

    2018-01-01

    Morel-Lavallee lesions (MLLs) are rare internal degloving injuries typically caused by blunt traumatic injuries and most commonly occur around the hips and in association with pelvic or acetabular fractures. MLL is often overlooked in the setting of poly-trauma; therefore, clinicians must maintain a high degree of suspicion and be familiar with the management of such injuries, especially in obese poly-trauma patients. We present a 30-year-old female pedestrian struck by a motor vehicle who sustained multiple long bone fractures, a mesenteric hematoma, and full-thickness abdominal skin friction burn which masked a significant underlying abdominal MLL. The internal degloving caused significant devascularization of the overlying soft tissue and skin which required surgical drainage of hematoma, abdominal wall reconstruction with tangential excision, allografting, negative pressure wound therapy, and ultimately autografting. MLL is a rare, often overlooked, internal degloving injury. Surgeons must maintain a high index of suspicion when dealing with third degree friction burns as they may mask underlying injuries such as MLL, and a delay in diagnosis can lead to increased morbidity.

  5. [Differential diagnosis of abdominal pain].

    PubMed

    Frei, Pascal

    2015-09-02

    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.

  6. Pseudotumors after primary abdominal lipectomy as a new sequela in patients with abdominal apron.

    PubMed

    Dragu, Adrian; Bach, Alexander D; Polykandriotis, Elias; Kneser, Ulrich; Horch, Raymund E

    2009-11-01

    Malnutrition and overweight is a common problem in modern societies. Primary abdominal lipectomy is a standard surgical tool in patients with these problems. However, unknown secondary problems result from recent advances in obesity surgery. Plication of the anterior musculoaponeurotic wall is a widely and commonly used operative technique during abdominoplasty. Many different plication techniques have been published. So far no common standard and long-term effectiveness is proven. In addition, there is no sufficient literature dealing with the postoperative risks of plication of the musculoaponeurotic wall. Four patients with development of pseudotumors were reviewed. All four patients received 12 months in advance a primary abdominal lipectomy including a vertical plication of the musculoaponeurotic wall. All four patients were females with mean age of 61 years and mean body mass index (BMI) of 37 kg/m(2). All four patients had developed a pseudotumor of the abdomen as a long-term complication more than 12 months after primary abdominal lipectomy including a vertical plication of the anterior rectus sheath. One should be aware of the potential long-term risk of secondary postoperative hematoma formation, with or without partial necrosis of the anterior rectus sheath after vertical plication of the anterior musculoaponeurotic wall. Viewed clinically and radiologically, such sequelas may appear as pseudotumor like masses and require immediate revision.

  7. Carbon nanotubes as VEGF carriers to improve the early vascularization of porcine small intestinal submucosa in abdominal wall defect repair

    PubMed Central

    Liu, Zhengni; Feng, Xueyi; Wang, Huichun; Ma, Jun; Liu, Wei; Cui, Daxiang; Gu, Yan; Tang, Rui

    2014-01-01

    Insufficient early vascularization in biological meshes, resulting in limited host tissue incorporation, is thought to be the primary cause for the failure of abdominal wall defect repair after implantation. The sustained release of exogenous angiogenic factors from a biocompatible nanomaterial might be a way to overcome this limitation. In the study reported here, multiwalled carbon nanotubes (MWNT) were functionalized by plasma polymerization to deliver vascular endothelial growth factor165 (VEGF165). The novel VEGF165-controlled released system was incorporated into porcine small intestinal submucosa (PSIS) to construct a composite scaffold. Scaffolds incorporating varying amounts of VEGF165-loaded functionalized MWNT were characterized in vitro. At 5 weight percent MWNT, the scaffolds exhibited optimal properties and were implanted in rats to repair abdominal wall defects. PSIS scaffolds incorporating VEGF165-loaded MWNT (VEGF–MWNT–PSIS) contributed to early vascularization from 2–12 weeks postimplantation and obtained more effective collagen deposition and exhibited improved tensile strength at 24 weeks postimplantation compared to PSIS or PSIS scaffolds, incorporating MWNT without VEGF165 loading (MWNT–PSIS). PMID:24648727

  8. How useful is abdominal ultrasonography in dogs with diarrhoea?

    PubMed

    Mapletoft, E K; Allenspach, K; Lamb, C R

    2018-01-01

    To assess the utility of abdominal ultrasonography in the diagnostic work-up of dogs with diarrhoea. Retrospective cross-sectional study based on a referral population of dogs with diarrhoea. Associations between the clinical signs, use of abdominal ultrasonography, results of abdominal ultrasonography and subsequent work-up were examined. The utility of abdominal ultrasonography was scored as high, moderate, none or counterproductive based on review of medical records. Medical records of 269 dogs were reviewed, of which 149 (55%) had abdominal ultrasonography. The most frequent result was no ultrasonographic abnormalities affecting the intestine in 65 (44%) dogs. Ultrasonography results were associated with subsequent work-up as follows: (1) no detected abnormalities and dietary trial; (2) focal thickening of the intestinal wall, loss of intestinal wall layers or enlarged abdominal lymph nodes and ultrasound-guided fine-needle aspirates; (3) diffuse thickening of the intestinal wall or hyperechoic striations in the small intestinal mucosa and endoscopy; and (4) small intestinal foreign body and coeliotomy. Abdominal ultrasonography was considered to be diagnostic without further testing in only four (3%) dogs: two had a portosystemic shunt identified ultrasonographically, one had a linear foreign body and one had a perforated pyloric ulcer. Abdominal ultrasonography had moderate utility in 56 (38%) dogs and no utility in 79 (53%) dogs. Abdominal ultrasonography was considered counterproductive in 10 (7%) dogs because results were either falsely negative or falsely positive. These results should prompt clinicians to reconsider routine use of abdominal ultrasonography in dogs with diarrhoea. © 2017 British Small Animal Veterinary Association.

  9. Simulation of Oscillatory Domain Wall Motion Driven by Spin Waves in Nanostrip with Perpendicular Magnetic Anisotropy

    NASA Astrophysics Data System (ADS)

    Lee, Shang Fan; Chang, Liang Juan; Spintronics Laboratory Team

    2014-03-01

    We numerically investigate the spin waves (SW) induced domain wall (DW) oscillatory motion in a nanostrip with perpendicular magnetic anisotropy by means of micromagnetic simulation. SW carries spin angular momentum and can interact with DWs via Spin Transfer Torque (STT). Propagating SW can drive a DW motion depending on the in-plane tilt angle φ of the wall magnetization. We calculate the instantaneous velocity of DWs as a function of φwith different SW frequency f. We find that the DW motion under propagating SW depends not only on the frequencies f, but also on the in-plane tilt angle φ. The nanostrip considered is 50 nm wide and 4000 nm long. A DW at the center is subjected to a SW source 500 nm apart on the left with amplitude in the transverse direction and varying frequency f. The motions of the DW induced by the SW are accompanied by in-plane rotation of magnetization of DW. Once rotated by 90 degrees, the DW shows a backward motion towards the SW source. The oscillatory amplitude and frequency of the DW motion is analyzed. A phase diagram will be presented. This study provides new perspectives for the control and manipulation of DW in a nanostrip. Financial supports by Academia Sinica and National Science Council are acknowledged

  10. Characterization of the mechanical behavior and pathophysiological state of abdominal aortic aneurysms based on 4D ultrasound strain imaging

    NASA Astrophysics Data System (ADS)

    Wittek, Andreas; Blase, Christopher; Derwich, Wojciech; Schmitz-Rixen, Thomas; Fritzen, Claus-Peter

    2017-06-01

    Abdominal aortic aneurysms (AAA) are a degenerative disease of the human aortic wall that may lead to weakening and eventually rupture of the wall with high mortality rates. Since the currently established criterion for surgical or endovascular treatment of the disease is imprecise in the individual case and treatment is not free of complications, the need for additional patient-individual biomarkers for short-term AAA rupture risk as basis for improved clinical decision making. Time resolved 3D ultrasound combined with speckle tracking algorithms is a novel non-invasive medical imaging technique that provides full-field displacement and strain measurements of aortic and aneurysmal wall motion. This is patient-individual information that has not been used so far to assess wall strength and rupture risk. The current study uses simple statistical indices of the heterogeneous spatial distribution of in-plane strain components as biomarkers for the pathological state of the aortic and aneurysmal wall. The pathophysiological rationale behind this approach are the known changes in microstructural composition of the aortic wall with progression of AAA development that results in increased stiffening and heterogeneity of the walls mechanical properties and in decreased wall strength. In a comparative analysis of the aortic wall motion of young volunteers without known cardiovascular diseases, aged arteriosclerotic patients without AAA, and AAA patients, mean values of all in-plane strain components were significantly reduced, and the heterogeneity of circumferential strain was significantly increased in the AAA group compared to both other groups. The capacity of the proposed method to differentiate between wall motion of aged, arteriosclerotic patients and AAA patients is a promising step towards a new method for in vivo assessment of AAA wall strength or stratification of AAA rupture risk as basis for improved clinical decision making on surgical or endovascular

  11. Primary undifferentiated small round cell sarcoma of the deep abdominal wall with a novel variant of t(10;19) CIC-DUX4 gene fusion.

    PubMed

    Tsukamoto, Yoshitane; Futani, Hiroyuki; Yoshiya, Shinichi; Watanabe, Takahiro; Kihara, Takako; Matsuo, Shohei; Hirota, Seiichi

    2017-10-01

    We experienced a 38-year-old Japanese male with t(10;19) CIC-DUX4 -positive undifferentiated small round cell sarcoma in the deep abdominal wall. Three months before his first visit to our hospital, he noticed a mass in his right abdominal wall. Computed tomography on admission revealed a solid abdominal tumor 70×53mm in size and multiple small tumors in both lungs. The biopsy of the abdominal tumor revealed undifferentiated small round cell sarcoma, suggestive of Ewing sarcoma. Under the clinical diagnosis of Ewing-like sarcoma of the abdominal wall with multiple lung metastases, several cycles of ICE (ifosfamide, carboplatin and etoposide) therapy were performed. After the chemotherapy, the lung metastases disappeared, while the primary lesion rapidly grew. Additional VDC (vincristine, doxorubicin and cyclophosphamide) therapy was carried out without apparent effect. Although the surgical removal of the primary lesion was done, peritoneal dissemination and a huge metastatic liver tumor appeared thereafter. The patient died of disease progression two months after the surgery. The total clinical course was approximately one year, showing that the tumor was extremely aggressive. The tumor cells of the surgical specimen were positive for CD99, WT1, calretinin, INI1, ERG and Fli1 by immunohistochemistry. Fusion gene analyses using the frozen surgical material revealed negativity for EWSR1-Fli1, EWSR1-ERG and t(4;19) CIC-DUX4 fusions, but positivity for t(10;19) CIC-DUX4 fusion. Thus, we made a final pathological diagnosis of t(10;19) CIC-DUX4-positive undifferentiated small round cell sarcoma. To our knowledge, this is the 13th case of t(10;19) CIC-DUX4 undifferentiated small round cell sarcoma with precise clinicopathological information. Especially in our case, two types of t(10;19) CIC-DUX4 fusion transcripts were observed, both of which are in-frame and novel. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. Abdominal MR imaging in children: motion compensation, sequence optimization, and protocol organization.

    PubMed

    Chavhan, Govind B; Babyn, Paul S; Vasanawala, Shreyas S

    2013-05-01

    Familiarity with basic sequence properties and their trade-offs is necessary for radiologists performing abdominal magnetic resonance (MR) imaging. Acquiring diagnostic-quality MR images in the pediatric abdomen is challenging due to motion, inability to breath hold, varying patient size, and artifacts. Motion-compensation techniques (eg, respiratory gating, signal averaging, suppression of signal from moving tissue, swapping phase- and frequency-encoding directions, use of faster sequences with breath holding, parallel imaging, and radial k-space filling) can improve image quality. Each of these techniques is more suitable for use with certain sequences and acquisition planes and in specific situations and age groups. Different T1- and T2-weighted sequences work better in different age groups and with differing acquisition planes and have specific advantages and disadvantages. Dynamic imaging should be performed differently in younger children than in older children. In younger children, the sequence and the timing of dynamic phases need to be adjusted. Different sequences work better in smaller children and in older children because of differing breath-holding ability, breathing patterns, field of view, and use of sedation. Hence, specific protocols should be maintained for younger children and older children. Combining longer-higher-resolution sequences and faster-lower-resolution sequences helps acquire diagnostic-quality images in a reasonable time. © RSNA, 2013.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ikeda, Osamu, E-mail: osamu-3643ik@do9.enjoy.ne.jp; Tamura, Yoshitaka; Nakasone, Yutaka

    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.

  14. Controlled motion of domain walls in submicron amorphous wires

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ţibu, Mihai; Lostun, Mihaela; Rotărescu, Cristian

    Results on the control of the domain wall displacement in cylindrical Fe{sub 77.5}Si{sub 7.5}B{sub 15} 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 firstmore » 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.« less

  15. Quantification of the relative contribution of the different right ventricular wall motion components to right ventricular ejection fraction: the ReVISION method.

    PubMed

    Lakatos, Bálint; Tősér, Zoltán; Tokodi, Márton; Doronina, Alexandra; Kosztin, Annamária; Muraru, Denisa; Badano, Luigi P; Kovács, Attila; Merkely, Béla

    2017-03-27

    Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction's ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.

  16. Energy-efficient writing scheme for magnetic domain-wall motion memory

    NASA Astrophysics Data System (ADS)

    Kim, Kab-Jin; Yoshimura, Yoko; Ham, Woo Seung; Ernst, Rick; Hirata, Yuushou; Li, Tian; Kim, Sanghoon; Moriyama, Takahiro; Nakatani, Yoshinobu; Ono, Teruo

    2017-04-01

    We present an energy-efficient magnetic domain-writing scheme for domain wall (DW) motion-based memory devices. A cross-shaped nanowire is employed to inject a domain into the nanowire through current-induced DW propagation. The energy required for injecting the magnetic domain is more than one order of magnitude lower than that for the conventional field-based writing scheme. The proposed scheme is beneficial for device miniaturization because the threshold current for DW propagation scales with the device size, which cannot be achieved in the conventional field-based technique.

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

    DOEpatents

    Armstrong, William D [Laramie, WY; Naughton, Jonathan [Laramie, WY; Lindberg, William R [Laramie, WY

    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.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muller, A., E-mail: arnaud.muller@chu-lyon.fr; Petrusca, L.; Auboiroux, V.

    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,more » 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.« less

  19. Abdominal organ motion during inhalation and exhalation breath-holds: pancreatic motion at different lung volumes compared.

    PubMed

    Lens, Eelco; Gurney-Champion, Oliver J; Tekelenburg, Daniël R; van Kesteren, Zdenko; Parkes, Michael J; van Tienhoven, Geertjan; Nederveen, Aart J; van der Horst, Astrid; Bel, Arjan

    2016-11-01

    Contrary to what is commonly assumed, organs continue to move during breath-holding. We investigated the influence of lung volume on motion magnitude during breath-holding and changes in velocity over the duration of breath-holding. Sixteen healthy subjects performed 60-second inhalation breath-holds in room-air, with lung volumes of ∼100% and ∼70% of the inspiratory capacity, and exhalation breath-holds, with lung volumes of ∼30% and ∼0% of the inspiratory capacity. During breath-holding, we obtained dynamic single-slice magnetic-resonance images with a time-resolution of 0.6s. We used 2-dimensional image correlation to obtain the diaphragmatic and pancreatic velocity and displacement during breath-holding. Organ velocity was largest in the inferior-superior direction and was greatest during the first 10s of breath-holding, with diaphragm velocities of 0.41mm/s, 0.29mm/s, 0.16mm/s and 0.15mm/s during BH 100% , BH 70% , BH 30% and BH 0% , respectively. Organ motion magnitudes were larger during inhalation breath-holds (diaphragm moved 9.8 and 9.0mm during BH 100% and BH 70% , respectively) than during exhalation breath-holds (5.6 and 4.3mm during BH 30% and BH 0% , respectively). Using exhalation breath-holds rather than inhalation breath-holds and delaying irradiation until after the first 10s of breath-holding may be advantageous for irradiation of abdominal tumors. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Observation of hohlraum-wall motion with spectrally selective x-ray imaging at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Izumi, N.; Meezan, N. B.; Divol, L.; Hall, G. N.; Barrios, M. A.; Jones, O.; Landen, O. L.; Kroll, J. J.; Vonhof, S. A.; Nikroo, A.; Jaquez, J.; Bailey, C. G.; Hardy, C. M.; Ehrlich, R. B.; Town, R. P. J.; Bradley, D. K.; Hinkel, D. E.; Moody, J. D.

    2016-11-01

    The high fuel capsule compression required for indirect drive inertial confinement fusion requires careful control of the X-ray drive symmetry throughout the laser pulse. When the outer cone beams strike the hohlraum wall, the plasma ablated off the hohlraum wall expands into the hohlraum and can alter both the outer and inner cone beam propagations and hence the X-ray drive symmetry especially at the final stage of the drive pulse. To quantitatively understand the wall motion, we developed a new experimental technique which visualizes the expansion and stagnation of the hohlraum wall plasma. Details of the experiment and the technique of spectrally selective x-ray imaging are discussed.

  1. Observation of hohlraum-wall motion with spectrally selective x-ray imaging at the National Ignition Facility.

    PubMed

    Izumi, N; Meezan, N B; Divol, L; Hall, G N; Barrios, M A; Jones, O; Landen, O L; Kroll, J J; Vonhof, S A; Nikroo, A; Jaquez, J; Bailey, C G; Hardy, C M; Ehrlich, R B; Town, R P J; Bradley, D K; Hinkel, D E; Moody, J D

    2016-11-01

    The high fuel capsule compression required for indirect drive inertial confinement fusion requires careful control of the X-ray drive symmetry throughout the laser pulse. When the outer cone beams strike the hohlraum wall, the plasma ablated off the hohlraum wall expands into the hohlraum and can alter both the outer and inner cone beam propagations and hence the X-ray drive symmetry especially at the final stage of the drive pulse. To quantitatively understand the wall motion, we developed a new experimental technique which visualizes the expansion and stagnation of the hohlraum wall plasma. Details of the experiment and the technique of spectrally selective x-ray imaging are discussed.

  2. 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

  3. 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.

  4. Elasticity mapping of murine abdominal organs in vivo using Harmonic Motion Imaging (HMI)

    PubMed Central

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

    2016-01-01

    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 tests. HMI was able to provide 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. HMI displacement 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 providing a crucial tool to understand pathologies affecting organ elasticity. PMID:27401609

  5. 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

    2016-08-07

    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.

  6. An oblique muscle hematoma as a rare cause of severe abdominal pain: a case report.

    PubMed

    Shimodaira, Masanori; Kitano, Tomohiro; Kibata, Minoru; Shirahata, Kumiko

    2013-01-18

    Abdominal wall hematomas are an uncommon cause of acute abdominal pain and are often misdiagnosed. They are more common in elderly individuals, particularly in those under anticoagulant therapy. Most abdominal wall hematomas occur in the rectus sheath, and hematomas within the oblique muscle are very rare and are poorly described in the literature. Here we report the case of an oblique muscle hematoma in a middle-aged patient who was not under anticoagulant therapy. A 42-year-old Japanese man presented with a painful, enlarging, lateral abdominal wall mass, which appeared after playing baseball. Abdominal computed tomography and ultrasonography showed a large soft tissue mass located in the patient's left internal oblique muscle. A diagnosis of a lateral oblique muscle hematoma was made and the patient was treated conservatively. Physicians should consider an oblique muscle hematoma during the initial differential diagnosis of pain in the lateral abdominal wall even in the absence of anticoagulant therapy or trauma.

  7. Respiratory motion correction for free-breathing 3D abdominal MRI using CNN-based image registration: a feasibility study.

    PubMed

    Lv, Jun; Yang, Ming; Zhang, Jue; Wang, Xiaoying

    2018-02-01

    Free-breathing abdomen imaging requires non-rigid motion registration of unavoidable respiratory motion in three-dimensional undersampled data sets. In this work, we introduce an image registration method based on the convolutional neural network (CNN) to obtain motion-free abdominal images throughout the respiratory cycle. Abdominal data were acquired from 10 volunteers using a 1.5 T MRI system. The respiratory signal was extracted from the central-space spokes, and the acquired data were reordered in three bins according to the corresponding breathing signal. Retrospective image reconstruction of the three near-motion free respiratory phases was performed using non-Cartesian iterative SENSE reconstruction. Then, we trained a CNN to analyse the spatial transform among the different bins. This network could generate the displacement vector field and be applied to perform registration on unseen image pairs. To demonstrate the feasibility of this registration method, we compared the performance of three different registration approaches for accurate image fusion of three bins: non-motion corrected (NMC), local affine registration method (LREG) and CNN. Visualization of coronal images indicated that LREG had caused broken blood vessels, while the vessels of the CNN were sharper and more consecutive. As shown in the sagittal view, compared to NMC and CNN, distorted and blurred liver contours were caused by LREG. At the same time, zoom-in axial images presented that the vessels were delineated more clearly by CNN than LREG. The statistical results of the signal-to-noise ratio, visual score, vessel sharpness and registration time over all volunteers were compared among the NMC, LREG and CNN approaches. The SNR indicated that the CNN acquired the best image quality (207.42 ± 96.73), which was better than NMC (116.67 ± 44.70) and LREG (187.93 ± 96.68). The image visual score agreed with SNR, marking CNN (3.85 ± 0.12) as the best, followed by LREG (3.43 ± 0

  8. Effect of exercise on hemodynamic conditions in the abdominal aorta.

    PubMed

    Taylor, C A; Hughes, T J; Zarins, C K

    1999-06-01

    The beneficial effect of exercise in the retardation of the progression of cardiovascular disease is hypothesized to be caused, at least in part, by the elimination of adverse hemodynamic conditions, including flow recirculation and low wall shear stress. In vitro and in vivo investigations have provided qualitative and limited quantitative information on flow patterns in the abdominal aorta and on the effect of exercise on the elimination of adverse hemodynamic conditions. We used computational fluid mechanics methods to examine the effects of simulated exercise on hemodynamic conditions in an idealized model of the human abdominal aorta. A three-dimensional computer model of a healthy human abdominal aorta was created to simulate pulsatile aortic blood flow under conditions of rest and graded exercise. Flow velocity patterns and wall shear stress were computed in the lesion-prone infrarenal aorta, and the effects of exercise were determined. A recirculation zone was observed to form along the posterior wall of the aorta immediately distal to the renal vessels under resting conditions. Low time-averaged wall shear stress was present in this location, along the posterior wall opposite the superior mesenteric artery and along the anterior wall between the superior and inferior mesenteric arteries. Shear stress temporal oscillations, as measured with an oscillatory shear index, were elevated in these regions. Under simulated light exercise conditions, a region of low wall shear stress and high oscillatory shear index remained along the posterior wall immediately distal to the renal arteries. Under simulated moderate exercise conditions, all the regions of low wall shear stress and high oscillatory shear index were eliminated. This numeric investigation provided detailed quantitative data on the effect of exercise on hemodynamic conditions in the abdominal aorta. Our results indicated that moderate levels of lower limb exercise are necessary to eliminate the flow

  9. Passive mechanical properties of rat abdominal wall muscles suggest an important role of the extracellular connective tissue matrix.

    PubMed

    Brown, Stephen H M; Carr, John Austin; Ward, Samuel R; Lieber, Richard L

    2012-08-01

    Abdominal wall muscles have a unique morphology suggesting a complex role in generating and transferring force to the spinal column. Studying passive mechanical properties of these muscles may provide insights into their ability to transfer force among structures. Biopsies from rectus abdominis (RA), external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) were harvested from male Sprague-Dawley rats, and single muscle fibers and fiber bundles (4-8 fibers ensheathed in their connective tissue matrix) were isolated and mechanically stretched in a passive state. Slack sarcomere lengths were measured and elastic moduli were calculated from stress-strain data. Titin molecular mass was also measured from single muscle fibers. No significant differences were found among the four abdominal wall muscles in terms of slack sarcomere length or elastic modulus. Interestingly, across all four muscles, slack sarcomere lengths were quite long in individual muscle fibers (>2.4 µm), and demonstrated a significantly longer slack length in comparison to fiber bundles (p < 0.0001). Also, the extracellular connective tissue matrix provided a stiffening effect and enhanced the resistance to lengthening at long muscle lengths. Titin molecular mass was significantly less in TrA compared to each of the other three muscles (p < 0.0009), but this difference did not correspond to hypothesized differences in stiffness. Copyright © 2012 Orthopaedic Research Society.

  10. The effects of temperature on the lattice barrier for twin wall motion

    NASA Astrophysics Data System (ADS)

    Zreihan, Noam; Faran, Eilon; Shilo, Doron

    2015-07-01

    The sideways motion of twin walls in ferroic materials requires overcoming an intrinsic energy barrier that originates from the periodicity of the crystal structure. Here, we measure the temperature dependence of the lattice barrier in a ferromagnetic Ni-Mn-Ga crystal using the pulsed magnetic field method. Our results reveal a monotonic decrease in the lattice barrier with increasing temperature. Yet, the barrier does not vanish as the temperature approaches the temperature of the martensite to austenite transformation. These findings enable the formulation of an analytical expression that correlates the lattice barrier to the physical properties of the twin wall, such as its thickness and the associated transformation strain. The derived relation provides a good quantitative description of the data measured in Ni-Mn-Ga.

  11. Observation of hohlraum-wall motion with spectrally selective x-ray imaging at the National Ignition Facility

    DOE PAGES

    Izumi, N.; Meezan, N. B.; Divol, L.; ...

    2016-08-12

    The high fuel capsule compression required for indirect drive inertial confinement fusion (ICF) requires careful control of the X-raydrive symmetry throughout the laser pulse. When the outer cone beams strike the hohlraum wall, the plasma ablated off the hohlraum wall expands into the hohlraum and can alter both the outer and inner cone beam propagation and hencethe X-raydrive symmetry especially at thefinal stage of the drive pulse. In order to quantitatively understand the wall motion, we developed a new experimental technique which visualizes the expansion and stagnation of the hohlraum wall plasma. Finally, we discuss details of the experiment andmore » the technique of spectrally selectivex-ray imaging.« less

  12. Observation of hohlraum-wall motion with spectrally selective x-ray imaging at the National Ignition Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Izumi, N., E-mail: izumi2@llnl.gov; Meezan, N. B.; Divol, L.

    The high fuel capsule compression required for indirect drive inertial confinement fusion requires careful control of the X-ray drive symmetry throughout the laser pulse. When the outer cone beams strike the hohlraum wall, the plasma ablated off the hohlraum wall expands into the hohlraum and can alter both the outer and inner cone beam propagations and hence the X-ray drive symmetry especially at the final stage of the drive pulse. To quantitatively understand the wall motion, we developed a new experimental technique which visualizes the expansion and stagnation of the hohlraum wall plasma. Details of the experiment and the techniquemore » of spectrally selective x-ray imaging are discussed.« less

  13. Observation of hohlraum-wall motion with spectrally selective x-ray imaging at the National Ignition Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Izumi, N.; Meezan, N. B.; Divol, L.

    The high fuel capsule compression required for indirect drive inertial confinement fusion (ICF) requires careful control of the X-raydrive symmetry throughout the laser pulse. When the outer cone beams strike the hohlraum wall, the plasma ablated off the hohlraum wall expands into the hohlraum and can alter both the outer and inner cone beam propagation and hencethe X-raydrive symmetry especially at thefinal stage of the drive pulse. In order to quantitatively understand the wall motion, we developed a new experimental technique which visualizes the expansion and stagnation of the hohlraum wall plasma. Finally, we discuss details of the experiment andmore » the technique of spectrally selectivex-ray imaging.« less

  14. Effect of spin transfer torque on domain wall motion regimes in [Co/Ni] superlattice wires

    NASA Astrophysics Data System (ADS)

    Le Gall, S.; Vernier, N.; Montaigne, F.; Thiaville, A.; Sampaio, J.; Ravelosona, D.; Mangin, S.; Andrieu, S.; Hauet, T.

    2017-05-01

    The combined effect of magnetic field and current on domain wall motion is investigated in epitaxial [Co/Ni] microwires. Both thermally activated and flow regimes are found to be strongly affected by current. All experimental data can be understood by taking into account both adiabatic and nonadiabatic components of the spin transfer torque, the parameters of which are extracted. In the precessional flow regime, it is shown that the domain wall can move in the electron flow direction against a strong applied field, as previously observed. In addition, for a large range of applied magnetic field and injected current, a stochastic domain wall displacement after each pulse is observed. Two-dimensional micromagnetic simulations, including some disorder, show a random fluctuation of the domain wall position that qualitatively matches the experimental results.

  15. Necrotizing Fasciitis of Thoracic and Abdominal Wall with Emphysematous Pyelonephritis and Retroperitoneal Abscess

    PubMed Central

    Khaladkar, Sanjay Mhalasakant; Jain, Kunaal Mahesh; Kuber, Rajesh; Gandage, Sidappa

    2018-01-01

    Emphysematous pyelonephritis is a life-threatening severe form of pyelonephritis usually occurring in patients with diabetes mellitus with or without obstructive uropathies in whom there is necrotizing infection leading to the gas production of an unclear mechanism involving the renal parenchyma and the collecting system. Necrotizing fasciitis is characterized by progressive necrosis of fat and fascia due to deep-seated infection of subcutaneous tissue. It has a fulminant course with considerable mortality. Diabetes Mellitus is a common predisposing factor. The combined occurrence of emphysematous pyelonephritis and necrotizing fasciitis is extremely unusual. Early recognition and management is mandatory to avoid mortality. We report a case of a 53-year-old female, a known case of Type II diabetes mellitus, who presented with necrotizing fasciitis of thoracic and abdominal wall with emphysematous pyelonephritis in the left kidney with a retroperitoneal abscess. PMID:29541493

  16. A systematic review of synthetic and biologic materials for abdominal wall reinforcement in contaminated fields.

    PubMed

    Lee, Lawrence; Mata, Juan; Landry, Tara; Khwaja, Kosar A; Vassiliou, Melina C; Fried, Gerald M; Feldman, Liane S

    2014-09-01

    Guidelines recommend the use of bioprosthetics for abdominal wall reinforcement in contaminated fields, but the evidence supporting the use of biologic over synthetic non-absorbable prosthetics for this indication is poor. Therefore, the objective was to perform a systematic review of outcomes after synthetic non-absorbable and biologic prosthetics for ventral hernia repair or prophylaxis in contaminated fields. The systematic literature search identified all articles published up to 2013 that reported outcomes after abdominal wall reinforcement using synthetic non-absorbable or biologic prosthetics in contaminated fields. Studies were included if they included at least 10 cases (excluding inguinal and parastomal hernias). Quality assessment was performed using the MINORS instrument. The main outcomes measures were the incidence of wound infection and hernia at follow-up. Weighted pooled proportions were calculated using a random effects model. A total of 32 studies met the inclusion criteria and were included for synthesis. Mean sample size was 41.4 (range 10-190), and duration of follow-up was >1 year in 72 % of studies. Overall quality was low (mean 6.2, range 1-12). Pooled wound infection rates were 31.6 % (95 % CI 14.5-48.7) with biologic and 6.4 % (95 % CI 3.4-9.4) with synthetic non-absorbable prosthetics in clean-contaminated cases, with similar hernia rates. In contaminated and/or dirty fields, wound infection rates were similar, but pooled hernia rates were 27.2 % (95 % CI 9.5-44.9) with biologic and 3.2 % (95 % CI 0.0-11.0) with synthetic non-absorbable. Other outcomes were comparable. The available evidence is limited, but does not support the superiority of biologic over synthetic non-absorbable prosthetics in contaminated fields.

  17. SU-D-207A-06: Pediatric Abdominal Organ Motion Quantified Via a Novel 4D MRI Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Uh, J; Krasin, MJ; Lucas, JT

    Purpose: To develop a 4D MRI method for assessing respiration-induced abdominal organ motion in children receiving radiation therapy. Methods: A 4D MRI using internal image-based respiratory surrogate has been developed and implemented on a clinical scanner (1.5T Siemens Avanto). Ten patients (younger group: N=6, 2–5 years, anesthetized; older group: N=4, 11–15 years) with neuroblastoma, Wilm’s tumor rhabdomyosarcoma, or desmoplastic small round cell tumor received free breathing 4D MRI scans for treatment planning. Coronal image slices of the entire abdomen were retrospectively constructed in 10 respiratory phases. A B-spline deformable registration (Metz et al. 2011) was performed on 4D datasets tomore » automatically derive motion trajectories of selected anatomical landmarks, including the dome and the center of the liver, and the superior edges of kidneys and spleen. The extents of the motion in three dimensions (anteroposterior, AP; mediolateral, ML; superoinferior, SI) and the correlations between organ motion trajectories were quantified. Results: The 4D MRI scans were successfully performed in <20 minutes for all patients without the use of any external device. Organ motion extents were larger in adolescents (kidneys: 3–13 mm SI, liver and spleen: 6–18 mm SI) than in younger children (kidneys:<3mm in all directions; liver and spleen: 1–8 mm SI, 1–5 mm ML and AP). The magnitude of respiratory motion in some adolescents may warrant special motion management. Motion trajectories were not synchronized across selected anatomical landmarks, particularly in the ML and AP directions, indicating inter- and intra-organ variations of the respiratory-induced motion. Conclusion: The developed 4D MRI acquisition and motion analysis methods provide a non-ionizing, non-invasive approach to automatically measure the organ motion trajectory in the pediatric abdomen. It is useful for defining ITV and PRV, monitoring changes in target motion patterns during

  18. Use of the temporal median and trimmed mean mitigates effects of respiratory motion in multiple-acquisition abdominal diffusion imaging.

    PubMed

    Jerome, N P; Orton, M R; d'Arcy, J A; Feiweier, T; Tunariu, N; Koh, D-M; Leach, M O; Collins, D J

    2015-01-21

    Respiratory motion commonly confounds abdominal diffusion-weighted magnetic resonance imaging, where averaging of successive samples at different parts of the respiratory cycle, performed in the scanner, manifests the motion as blurring of tissue boundaries and structural features and can introduce bias into calculated diffusion metrics. Storing multiple averages separately allows processing using metrics other than the mean; in this prospective volunteer study, median and trimmed mean values of signal intensity for each voxel over repeated averages and diffusion-weighting directions are shown to give images with sharper tissue boundaries and structural features for moving tissues, while not compromising non-moving structures. Expert visual scoring of derived diffusion maps is significantly higher for the median than for the mean, with modest improvement from the trimmed mean. Diffusion metrics derived from mono- and bi-exponential diffusion models are comparable for non-moving structures, demonstrating a lack of introduced bias from using the median. The use of the median is a simple and computationally inexpensive alternative to complex and expensive registration algorithms, requiring only additional data storage (and no additional scanning time) while returning visually superior images that will facilitate the appropriate placement of regions-of-interest when analysing abdominal diffusion-weighted magnetic resonance images, for assessment of disease characteristics and treatment response.

  19. Use of the temporal median and trimmed mean mitigates effects of respiratory motion in multiple-acquisition abdominal diffusion imaging

    NASA Astrophysics Data System (ADS)

    Jerome, N. P.; Orton, M. R.; d'Arcy, J. A.; Feiweier, T.; Tunariu, N.; Koh, D.-M.; Leach, M. O.; Collins, D. J.

    2015-01-01

    Respiratory motion commonly confounds abdominal diffusion-weighted magnetic resonance imaging, where averaging of successive samples at different parts of the respiratory cycle, performed in the scanner, manifests the motion as blurring of tissue boundaries and structural features and can introduce bias into calculated diffusion metrics. Storing multiple averages separately allows processing using metrics other than the mean; in this prospective volunteer study, median and trimmed mean values of signal intensity for each voxel over repeated averages and diffusion-weighting directions are shown to give images with sharper tissue boundaries and structural features for moving tissues, while not compromising non-moving structures. Expert visual scoring of derived diffusion maps is significantly higher for the median than for the mean, with modest improvement from the trimmed mean. Diffusion metrics derived from mono- and bi-exponential diffusion models are comparable for non-moving structures, demonstrating a lack of introduced bias from using the median. The use of the median is a simple and computationally inexpensive alternative to complex and expensive registration algorithms, requiring only additional data storage (and no additional scanning time) while returning visually superior images that will facilitate the appropriate placement of regions-of-interest when analysing abdominal diffusion-weighted magnetic resonance images, for assessment of disease characteristics and treatment response.

  20. In vitro fertilization surrogate pregnancy in a patient who underwent radical hysterectomy followed by ovarian transposition, lower abdominal wall radiotherapy, and chemotherapy.

    PubMed

    Steigrad, Stephen; Hacker, Neville F; Kolb, Bradford

    2005-05-01

    To describe an IVF surrogate pregnancy from a patient who had a radical hysterectomy followed by excision of a laparoscopic port site implantation with ovarian transposition followed by abdominal wall irradiation and chemotherapy, which resulted in premature ovarian failure from which there was partial recovery. Case report. Tertiary referral university women's hospital in Sydney, Australia and private reproductive medicine clinic in California. A 34-year-old woman who underwent laparoscopy for pelvic pain, shortly afterward followed by radical hysterectomy and pelvic lymph node dissection, who subsequently developed a laparoscopic port site recurrence, which was excised in association with ovarian transposition before abdominal wall irradiation and chemotherapy. Modified IVF treatment, transabdominal oocyte retrieval, embryo cryopreservation in Australia, and transfer to a surrogate mother in the United States. Pregnancy. Miscarriage in the second cycle and a twin pregnancy in the fourth cycle. This is the first case report of ovarian stimulation and oocyte retrieval performed on transposed ovaries after a patient developed premature ovarian failure after radiotherapy and chemotherapy with subsequent partial ovarian recovery.

  1. Management of enterocutaneous fistulas and problem stomas with silicone casting of the abdominal wall defect.

    PubMed

    Streza, G A; Laing, B J; Gilsdorf, R B

    1977-12-01

    Silicone casting of abdominal wall defects around enteric fistulas in six patients and problem stomas in three patients proved to be an effective means of controlling the output of the fistulas, reducing wound care time, and reducing or eliminating parenteral nutrition needs. Outpatient management was possible in seven of the nine patients. It is observed that the wounds healed rapidly with this method of fistula control. Epithelialization occurred more rapidly than expected. This method of management may tend to make the fistulas remain open longer than by other means of care, but the significant increase in patient comfort, the financial savings, and the relative safety warrant continued utilization and observation of this method of management.

  2. Abdominothoracic mechanisms of functional abdominal distension and correction by biofeedback.

    PubMed

    Barba, Elizabeth; Burri, Emanuel; Accarino, Anna; Cisternas, Daniel; Quiroga, Sergi; Monclus, Eva; Navazo, Isabel; Malagelada, Juan-R; Azpiroz, Fernando

    2015-04-01

    In patients with functional gut disorders, abdominal distension has been associated with descent of the diaphragm and protrusion of the anterior abdominal wall. We investigated mechanisms of abdominal distension in these patients. We performed a prospective study of 45 patients (42 women, 24-71 years old) with functional intestinal disorders (27 with irritable bowel syndrome with constipation, 15 with functional bloating, and 3 with irritable bowel syndrome with alternating bowel habits) and discrete episodes of visible abdominal distension. Subjects were assessed by abdominothoracic computed tomography (n = 39) and electromyography (EMG) of the abdominothoracic wall (n = 32) during basal conditions (without abdominal distension) and during episodes of severe abdominal distension. Fifteen patients received a median of 2 sessions (range, 1-3 sessions) of EMG-guided, respiratory-targeted biofeedback treatment; 11 received 1 control session before treatment. Episodes of abdominal distension were associated with diaphragm contraction (19% ± 3% increase in EMG score and 12 ± 2 mm descent; P < .001 vs basal values) and intercostal contraction (14% ± 3% increase in EMG scores and 6 ± 1 mm increase in thoracic antero-posterior diameter; P < .001 vs basal values). They were also associated with increases in lung volume (501 ± 93 mL; P < .001 vs basal value) and anterior abdominal wall protrusion (32 ± 3 mm increase in girth; P < .001 vs basal). Biofeedback treatment, but not control sessions, reduced the activity of the intercostal muscles (by 19% ± 2%) and the diaphragm (by 18% ± 4%), activated the internal oblique muscles (by 52% ± 13%), and reduced girth (by 25 ± 3 mm) (P ≤ .009 vs pretreatment for all). In patients with functional gut disorders, abdominal distension is a behavioral response that involves activity of the abdominothoracic wall. This distension can be reduced with EMG-guided, respiratory-targeted biofeedback therapy. Copyright © 2015 AGA

  3. Verification of an optimized stimulation point on the abdominal wall for transcutaneous neuromuscular electrical stimulation for activation of deep lumbar stabilizing muscles.

    PubMed

    Baek, Seung Ok; Cho, Hee Kyung; Jung, Gil Su; Son, Su Min; Cho, Yun Woo; Ahn, Sang Ho

    2014-09-01

    Transcutaneous neuromuscular electrical stimulation (NMES) can stimulate contractions in deep lumbar stabilizing muscles. An optimal protocol has not been devised for the activation of these muscles by NMES, and information is lacking regarding an optimal stimulation point on the abdominal wall. The goal was to determine a single optimized stimulation point on the abdominal wall for transcutaneous NMES for the activation of deep lumbar stabilizing muscles. Ultrasound images of the spinal stabilizing muscles were captured during NMES at three sites on the lateral abdominal wall. After an optimal location for the placement of the electrodes was determined, changes in the thickness of the lumbar multifidus (LM) were measured during NMES. Three stimulation points were investigated using 20 healthy physically active male volunteers. A reference point R, 1 cm superior to the iliac crest along the midaxillary line, was used. Three study points were used: stimulation point S1 was located 2 cm superior and 2 cm medial to the anterior superior iliac spine, stimulation point S3 was 2 cm below the lowest rib along the same sagittal plane as S1, and stimulation point S2 was midway between S1 and S3. Sessions were conducted stimulating at S1, S2, or S3 using R for reference. Real-time ultrasound imaging (RUSI) of the abdominal muscles was captured during each stimulation session. In addition, RUSI images were captured of the LM during stimulation at S1. Thickness, as measured by RUSI, of the transverse abdominis (TrA), obliquus internus, and obliquus externus was greater during NMES than at rest for all three study points (p<.05). Transverse abdominis was significantly stimulated more by NMES at S1 than at the other points (p<.05). The LM thickness was also significantly greater during NMES at S1 than at rest (p<.05). Neuromuscular electrical stimulation at S1 optimally activated deep spinal stabilizing muscles, TrA and LM, as evidenced by RUSI. The authors recommend this

  4. [Evaluation of echocardiographic left ventricular wall motion analysis supported by internet picture viewing system].

    PubMed

    Hirano, Yutaka; Ikuta, Shin-Ichiro; Nakano, Manabu; Akiyama, Seita; Nakamura, Hajime; Nasu, Masataka; Saito, Futoshi; Nakagawa, Junichi; Matsuzaki, Masashi; Miyazaki, Shunichi

    2007-02-01

    Assessment of deterioration of regional wall motion by echocardiography is not only subjective but also features difficulties with interobserver agreement. Progress in digital communication technology has made it possible to send video images from a distant location via the Internet. The possibility of evaluating left ventricular wall motion using video images sent via the Internet to distant institutions was evaluated. Twenty-two subjects were randomly selected. Four sets of video images (parasternal long-axis view, parasternal short-axis view, apical four-chamber view, and apical two-chamber view) were taken for one cardiac cycle. The images were sent via the Internet to two institutions (observer C in facility A and observers D and E in facility B) for evaluation. Great care was taken to prevent disclosure of patient information to these observers. Parasternal long-axis images were divided into four segments, and the parasternal short-axis view, apical four-chamber view, and apical two-chamber view were divided into six segments. One of the following assessments, normokinesis, hypokinesis, akinesis, or dyskinesis, was assigned to each segment. The interobserver rates of agreement in judgments between observers C and D, observers C and E, and intraobserver agreement rate (for observer D) were calculated. The rate of interobserver agreement was 85.7% (394/460 segments; Kappa = 0.65) between observers C and D, 76.7% (353/460 segments; Kappa = 0.39) between observers D and E, and 76.3% (351/460 segments; Kappa = 0.36)between observers C and E, and intraobserver agreement was 94.3% (434/460; Kappa = 0.86). Segments of difference judgments between observers C and D were normokinesis-hypokinesis; 62.1%, hypokinesis-akinesis; 33.3%, akinesis-dyskinesis; 3.0%, and normokinesis-akinesis; 1.5%. Wall motion can be evaluated at remote institutions via the Internet.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsang, Derek S.; Voncken, Francine E.M.; Tse, Regina V.

    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 bymore » 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.« less

  6. Abdominal Wall Reconstruction with Concomitant Ostomy-Associated Hernia Repair: Outcomes and Propensity Score Analysis.

    PubMed

    Mericli, Alexander F; Garvey, Patrick B; Giordano, Salvatore; Liu, Jun; Baumann, Donald P; Butler, Charles E

    2017-03-01

    The optimal strategy for abdominal wall reconstruction in the presence of a stomal-site hernia is unclear. We hypothesized that the rate of ventral hernia recurrence in patients undergoing a combined ventral hernia repair and stomal-site herniorraphy would not differ clinically from the ventral hernia recurrence rate in patients undergoing an isolated ventral hernia repair. We also hypothesized that bridged ventral hernia repairs result in worse outcomes compared with reinforced repairs, regardless of stomal hernia. We retrospectively reviewed prospectively collected data from consecutive abdominal wall reconstructions performed with acellular dermal matrix (ADM) at a single center between 2000 and 2015. We compared patients who underwent a ventral hernia repair alone (AWR) and those who underwent both a ventral hernia repair and ostomy-associated herniorraphy (AWR+O). We conducted a propensity score matched analysis to compare the outcomes between the 2 groups. Multivariable Cox proportional hazards and logistic regression models were used to study associations between potential predictive or protective reconstructive strategies and surgical outcomes. We included 499 patients (median follow-up 27.2 months; interquartile range [IQR] 12.4 to 46.6 months), 118 AWR+O and 381 AWR. After propensity score matching, 91 pairs were obtained. Ventral hernia recurrence was not statistically associated with ostomy-associated herniorraphy (adjusted hazard ratio [HR] 0.7; 95% CI 0.3 to 1.5; p = 0.34). However, the AWR+O group experienced a significantly higher percentage of surgical site occurrences (34.1%) than the AWR group (18.7%; adjusted odds ratio 2.3; 95% CI 1.4 to 3.7; p < 0.001). In the AWR group, there were significantly fewer ventral hernia recurrences when the repair was reinforced compared with bridged (5.3% vs 38.5%; p < 0.001). There was no statistically significant difference in ventral hernia recurrence between the AWR and AWR+O groups. Bridging was associated

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ai, J. H.; Miao, B. F.; Sun, L.

    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 nonadiabaticmore » 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.« less

  8. Abdominal elephantiasis: a case report.

    PubMed

    Hanna, Dominique; Cloutier, Richard; Lapointe, Roch; Desgagné, Antoine

    2004-01-01

    Elephantiasis is a well-known condition in dermatology usually affecting the legs and external genitalia. It is characterized by chronic inflammation and obstruction of the lymphatic channels and by hypertrophy of the skin and subcutaneous tissues. The etiology is either idiopathic or caused by a variety of conditions such as chronic filarial disease, leprosy, leishmaniasis, and chronic recurrent cellulites. Elephantiasis of the abdominal wall is very rare. A complete review of the English and French literature showed only two cases reported in 1966 and 1973, respectively. We report a third case of abdominal elephantiasis and we briefly review this entity. We present the case of a 51-year-old woman who had progressively developed an enormous pediculated abdominal mass hanging down her knees. The skin was thickened, hyperpigmented, and fissured. She had a history of multiple abdominal cellulites. She underwent an abdominal lipectomy. Histopathology of the specimen confirmed the diagnosis of abdominal elephantiasis. Abdominal elephantiasis is a rare disease that represents end-stage failure of lymph drainage. Lipectomy should be considered in the management of this condition.

  9. Steady motion of skyrmions and domains walls under diffusive spin torques

    NASA Astrophysics Data System (ADS)

    Elías, Ricardo Gabriel; Vidal-Silva, Nicolas; Manchon, Aurélien

    2017-03-01

    We explore the role of the spin diffusion of conducting electrons in two-dimensional magnetic textures (domain walls and skyrmions) with spatial variation of the order of the spin precession length λex. The effect of diffusion reflects in four additional torques that are third order in spatial derivatives of magnetization and bilinear in λex and in the nonadiabatic parameter β'. In order to study the dynamics of the solitons when these diffusive torques are present, we derive the Thiele equation in the limit of steady motion and we compare the results with the nondiffusive limit. When considering a homogenous current these torques increase the longitudinal velocity of transverse domain walls of width Δ by a factor (λex/Δ)2(α/3), α being the magnetic damping constant. In the case of single skyrmions with core radius r0these new contributions tend to increase the Magnus effect in an amount proportional to (λex/r0) 2(1 +2 α β') .

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Y; Shi, F; Tian, Z

    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 motionmore » 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

  11. Ultrasonographic abdominal anatomy of healthy captive caracals (Caracal caracal).

    PubMed

    Makungu, Modesta; du Plessis, Wencke M; Barrows, Michelle; Koeppel, Katja N; Groenewald, Hermanus B

    2012-09-01

    Abdominal ultrasonography was performed in six adult captive caracals (Caracal caracal) to describe the normal abdominal ultrasonographic anatomy. Consistently, the splenic parenchyma was hyperechoic to the liver and kidneys. The relative echogenicity of the right kidney's cortex was inconsistent to the liver. The gall bladder was prominent in five animals and surrounded by a clearly visualized thin, smooth, regular echogenic wall. The wall thickness of the duodenum measured significantly greater compared with that of the jejunum and colon. The duodenum had a significantly thicker mucosal layer compared with that of the stomach. Such knowledge of the normal abdominal ultrasonographic anatomy of individual species is important for accurate diagnosis and interpretation of routine health examinations.

  12. Operative correction of abdominal rectus diastasis (ARD) reduces pain and improves abdominal wall muscle strength: A randomized, prospective trial comparing retromuscular mesh repair to double-row, self-retaining sutures.

    PubMed

    Emanuelsson, Peter; Gunnarsson, Ulf; Dahlstrand, Ursula; Strigård, Karin; Stark, Birgit

    2016-11-01

    The primary aim of this prospective, randomized, clinical, 2-armed trial was to evaluate the risk for recurrence using 2 different operative techniques for repair of abdominal rectus diastasis. Secondary aims were comparison of pain, abdominal muscle strength, and quality of life and to compare those outcomes to a control group receiving physical training only. Eighty-six patients were enrolled. Twenty-nine patients were allocated to retromuscular polypropylene mesh and 27 to double-row plication with Quill technology. Thirty-two patients participated in a 3-month training program. Diastasis was evaluated with computed tomography scan and clinically. Pain was assessed using the ventral hernia pain questionnaire, a quality-of-life survey, SF-36, and abdominal muscle strength using the Biodex System-4. One early recurrence occurred in the Quill group, 2 encapsulated seromas in the mesh group, and 3 in the suture group. Significant improvements in perceived pain, the ventral hernia pain questionnaire, and quality of life appeared at the 1-year follow-up with no difference between the 2 operative groups. Significant muscular improvement was obtained in all groups (Biodex System-4). Patient perceived gain in muscle strength assessed with a visual analog scale improved similarly in both operative groups. This improvement was significantly greater than that seen in the training group. Patients in the training group still experienced bodily pain at follow-up. There was no difference between the Quill technique and retromuscular mesh in the effect on abdominal wall stability, with a similar complication rate 1 year after operation. An operation improves functional ability and quality of life. Training strengthens the abdominal muscles, but patients still experience discomfort and pain. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. 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.

  14. Coupled, circumferential motions of the cell wall synthesis machinery and MreB filaments in B. subtilis.

    PubMed

    Garner, Ethan C; Bernard, Remi; Wang, Wenqin; Zhuang, Xiaowei; Rudner, David Z; Mitchison, Tim

    2011-07-08

    Rod-shaped bacteria elongate by the action of cell wall synthesis complexes linked to underlying dynamic MreB filaments. To understand how the movements of these filaments relate to cell wall synthesis, we characterized the dynamics of MreB and the cell wall elongation machinery using high-precision particle tracking in Bacillus subtilis. We found that MreB and the elongation machinery moved circumferentially around the cell, perpendicular to its length, with nearby synthesis complexes and MreB filaments moving independently in both directions. Inhibition of cell wall synthesis by various methods blocked the movement of MreB. Thus, bacteria elongate by the uncoordinated, circumferential movements of synthetic complexes that insert radial hoops of new peptidoglycan during their transit, possibly driving the motion of the underlying MreB filaments.

  15. Marker-less respiratory motion modeling using the Microsoft Kinect for Windows

    NASA Astrophysics Data System (ADS)

    Tahavori, F.; Alnowami, M.; Wells, K.

    2014-03-01

    Patient respiratory motion is a major problem during external beam radiotherapy of the thoracic and abdominal regions due to the associated organ and target motion. In addition, such motion introduces uncertainty in both radiotherapy planning and delivery and may potentially vary between the planning and delivery sessions. The aim of this work is to examine subject-specific external respiratory motion and its associated drift from an assumed average cycle which is the basis for many respiratory motion compensated applications including radiotherapy treatment planning and delivery. External respiratory motion data were acquired from a group of 20 volunteers using a marker-less 3D depth camera, Kinect for Windows. The anterior surface encompassing thoracic and abdominal regions were subject to principal component analysis (PCA) to investigate dominant variations. The first principal component typically describes more than 70% of the motion data variance in the thoracic and abdominal surfaces. Across all of the subjects used in this study, 58% of subjects demonstrate largely abdominal breathing and 33% exhibited largely thoracic dominated breathing. In most cases there is observable drift in respiratory motion during the 300s capture period, which is visually demonstrated using Kernel Density Estimation. This study demonstrates that for this cohort of apparently healthy volunteers, there is significant respiratory motion drift in most cases, in terms of amplitude and relative displacement between the thoracic and abdominal respiratory components. This has implications for the development of effective motion compensation methodology.

  16. Lymphedema of the Transplanted Kidney and Abdominal Wall with Ipsilateral Pleural Effusion Following Kidney Biopsy in a Patient Treated with Sirolimus: A Case Report and Review of the Literature.

    PubMed

    Rashid-Farokhi, Farin; Afshar, Haleh

    2017-12-22

    BACKGROUND Sirolimus is a mammalian target of rapamycin (mTOR) inhibitor, which is used in immunosuppressive treatment regimens in organ transplant recipients. Although mTOR inhibitors are well tolerated, their adverse effects have been reported. Sirolimus treatment in transplant recipients has been reported to be associated with lymphedema of the skin and subcutaneous tissues, and with pleural effusion, but edema of internal organs and organomegaly have not been previously reported. A case is presented lymphedema of the transplanted kidney and abdominal wall with ipsilateral pleural effusion following kidney biopsy in a patient treated with sirolimus. CASE REPORT A 32-year-old woman with a history of end-stage renal disease of unknown etiology had undergone right renal transplantation from an unrelated living donor, eight years previously. She was referred to our hospital with dyspnea, localized abdominal pain, and swelling of the transplanted kidney. The symptoms appeared following a kidney biopsy and the replacement of cyclosporin with sirolimus four months previously. On examination, she had localized swelling of the abdominal wall overlying the transplanted kidney, and a right pleural effusion. Hydronephrosis and nephrotic syndrome were excluded as causes of kidney enlargement. Following the withdrawal of sirolimus therapy her symptoms resolved within three months. CONCLUSIONS A case is described of lymphedema of the transplanted kidney and abdominal wall with ipsilateral pleural effusion following kidney biopsy attributed to her change in anti-rejection therapy to sirolimus. This case report should raise awareness of this unusual complication of sirolimus anti-rejection therapy and its possible effects on the lymphatic system.

  17. Concurrent Respiratory Motion Correction of Abdominal PET and DCE-MRI using a Compressed Sensing Approach.

    PubMed

    Fuin, Niccolo; Catalano, Onofrio Antonio; Scipioni, Michele; Canjels, Lisanne P W; Izquierdo, David; Pedemonte, Stefano; Catana, Ciprian

    2018-01-25

    Purpose: We present an approach for concurrent reconstruction of respiratory motion compensated abdominal DCE-MRI and PET data in an integrated PET/MR scanner. The MR and PET reconstructions share the same motion vector fields (MVFs) derived from radial MR data; the approach is robust to changes in respiratory pattern and do not increase the total acquisition time. Methods: PET and DCE-MRI data of 12 oncological patients were simultaneously acquired for 6 minutes on an integrated PET/MR system after administration of 18 F-FDG and gadoterate meglumine. Golden-angle radial MR data were continuously acquired simultaneously with PET data and sorted into multiple motion phases based on a respiratory signal derived directly from the radial MR data. The resulting multidimensional dataset was reconstructed using a compressed sensing approach that exploits sparsity among respiratory phases. MVFs obtained using the full 6-minute (MC_6-min) and only the last 1 minute (MC_1-min) of data were incorporated into the PET reconstruction to obtain motion-corrected PET images and in an MR iterative reconstruction algorithm to produce a series of motion-corrected DCE-MRI images (moco_GRASP). The motion-correction methods (MC_6-min and MC_1-min) were evaluated by qualitative analysis of the MR images and quantitative analysis of maximum and mean standardized uptake values (SUV max , SUVmean), contrast, signal-to-noise ratio (SNR) and lesion volume in the PET images. Results: Motion corrected MC_6-min PET images demonstrated 30%, 23%, 34% and 18% increases in average SUV max , SUVmean, contrast and SNR, and an average 40% reduction in lesion volume with respect to the non-motion-corrected PET images. The changes in these figures of merit were smaller but still substantial for the MC_1-min protocol: 19%, 10%, 15% and 9% increases in average SUV max , SUVmean, contrast and SNR; and a 28% reduction in lesion volume. Moco_GRASP images were deemed of acceptable or better diagnostic image

  18. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Polypropylene-based composite mesh versus standard polypropylene mesh in the reconstruction of complicated large abdominal wall hernias: a prospective randomized study.

    PubMed

    Kassem, M I; El-Haddad, H M

    2016-10-01

    To compare polypropylene mesh positioned onlay supported by omentum and/or peritoneum versus inlay implantation of polypropylene-based composite mesh in patients with complicated wide-defect ventral hernias. This was a prospective randomized study carried out on 60 patients presenting with complicated large ventral hernia in the period from January 2012 to January 2016 in the department of Gastrointestinal Surgery unit and Surgical Emergency of the Main Alexandria University Hospital, Egypt. Large hernia had an abdominal wall defect that could not be closed. Patients were divided into two groups of 30 patients according to the type of mesh used to deal with the large abdominal wall defect. The study included 38 women (63.3 %) and 22 men (37.7 %); their mean age was 46.5 years (range, 25-70). Complicated incisional hernia was the commonest presentation (56.7 %).The operative and mesh fixation times were longer in the polypropylene group. Seven wound infections and two recurrences were encountered in the propylene group. Mean follow-up was 28.7 months (2-48 months). Composite mesh provided, in one session, satisfactory results in patients with complicated large ventral hernia. The procedure is safe and effective in lowering operative time with a trend of low wound complication and recurrence rates.

  20. Light effects in the atomic-motion-induced Ramsey narrowing of dark resonances in wall-coated cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Breschi, E.; Schori, C.; Di Domenico, G.

    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 ofmore » 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.« less

  1. Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction.

    PubMed

    Fujino, Takayuki; Ishii, Yoshinao; Takeuchi, Toshiharu; Hirasawa, Kunihiko; Tateda, Kunihiko; Kikuchi, Kenjiro; Hasebe, Naoyuki

    2003-09-01

    The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-beta-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The insulin resistance (IR), estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion.

  2. The influence of computational assumptions on analysing abdominal aortic aneurysm haemodynamics.

    PubMed

    Ene, Florentina; Delassus, Patrick; Morris, Liam

    2014-08-01

    The variation in computational assumptions for analysing abdominal aortic aneurysm haemodynamics can influence the desired output results and computational cost. Such assumptions for abdominal aortic aneurysm modelling include static/transient pressures, steady/transient flows and rigid/compliant walls. Six computational methods and these various assumptions were simulated and compared within a realistic abdominal aortic aneurysm model with and without intraluminal thrombus. A full transient fluid-structure interaction was required to analyse the flow patterns within the compliant abdominal aortic aneurysms models. Rigid wall computational fluid dynamics overestimates the velocity magnitude by as much as 40%-65% and the wall shear stress by 30%-50%. These differences were attributed to the deforming walls which reduced the outlet volumetric flow rate for the transient fluid-structure interaction during the majority of the systolic phase. Static finite element analysis accurately approximates the deformations and von Mises stresses when compared with transient fluid-structure interaction. Simplifying the modelling complexity reduces the computational cost significantly. In conclusion, the deformation and von Mises stress can be approximately found by static finite element analysis, while for compliant models a full transient fluid-structure interaction analysis is required for acquiring the fluid flow phenomenon. © IMechE 2014.

  3. Strain-encoded cardiac MRI as an adjunct for dobutamine stress testing: incremental value to conventional wall motion analysis.

    PubMed

    Korosoglou, Grigorios; Lossnitzer, Dirk; Schellberg, Dieter; Lewien, Antje; Wochele, Angela; Schaeufele, Tim; Neizel, Mirja; Steen, Henning; Giannitsis, Evangelos; Katus, Hugo A; Osman, Nael F

    2009-03-01

    High-dose dobutamine stress MRI is safe and feasible for the diagnosis of coronary artery disease (CAD) in humans. However, the assessment of cine scans relies on the visual interpretation of regional wall motion, which is subjective. Recently, strain-encoded MRI (SENC) has been proposed for the direct color-coded visualization of myocardial strain. The purpose of our study was to compare the diagnostic value of SENC with that provided by conventional wall motion analysis for the detection of inducible ischemia during dobutamine stress MRI. Stress-induced ischemia was assessed by wall motion analysis and by SENC in 101 patients with suspected or known CAD and in 17 healthy volunteers who underwent dobutamine stress MRI in a clinical 1.5-T scanner. Quantitative coronary angiography deemed as the standard reference for the presence or absence of significant CAD (> or =50% diameter stenosis). On a coronary vessel level, SENC detected inducible ischemia in 86 of 101 versus 71 of 101 diseased coronary vessels (P<0.01 versus cine) and showed normal strain response in 189 of 202 versus 194 of 202 vessels with <50% stenosis (P=NS versus cine). On a patient level, SENC detected inducible ischemia in 63 of 64 versus 55 of 64 patients with CAD (P<0.05 versus cine) and showed normal strain response in 32 of 37 versus 34 of 37 patients without CAD (P=NS versus cine). Quantification analysis demonstrated a significant correlation between strain rate reserve and coronary artery stenosis severity (r(2)=0.56, P<0.001), and a cutoff value of strain rate reserve of 1.64 was deemed as a highly accurate marker for the detection of > or =50% stenosis (area under the curve, 0.96; SE, 0.01; 95% CI, 0.94 to 0.98; P<0.001). The direct color-coded visualization of strain on MR images is a useful adjunct for dobutamine stress MRI, which provides incremental value for the detection of CAD compared with conventional wall motion readings on cine images.

  4. Role of spin diffusion in current-induced domain wall motion for disordered ferromagnets

    NASA Astrophysics Data System (ADS)

    Akosa, Collins Ashu; Kim, Won-Seok; Bisig, André; Kläui, Mathias; Lee, Kyung-Jin; Manchon, Aurélien

    2015-03-01

    Current-induced spin transfer torque and magnetization dynamics in the presence of spin diffusion in disordered magnetic textures is studied theoretically. We demonstrate using tight-binding calculations that weak, spin-conserving impurity scattering dramatically enhances the nonadiabaticity. To further explore this mechanism, a phenomenological drift-diffusion model for incoherent spin transport is investigated. We show that incoherent spin diffusion indeed produces an additional spatially dependent torque of the form ˜∇2[m ×(u .∇ ) m ] +ξ ∇2[(u .∇ ) m ] , where m is the local magnetization direction, u is the direction of injected current, and ξ is a parameter characterizing the spin dynamics (precession, dephasing, and spin-flip). This torque, which scales as the inverse square of the domain wall width, only weakly enhances the longitudinal velocity of a transverse domain wall but significantly enhances the transverse velocity of vortex walls. The spatial-dependent spin transfer torque uncovered in this study is expected to have significant impact on the current-driven motion of abrupt two-dimensional textures such as vortices, skyrmions, and merons.

  5. Simultaneous Assessment of Myocardial Perfusion, Wall Motion, and Deformation during Myocardial Contrast Echocardiography: A Feasibility Study.

    PubMed

    Zoppellaro, Giacomo; Venneri, Lucia; Khattar, Rajdeep S; Li, Wei; Senior, Roxy

    2016-06-01

    Ultrasound contrast agents may be used for the assessment of regional wall motion and myocardial perfusion, but are generally considered not suitable for deformation analysis. The aim of our study was to assess the feasibility of deformation imaging on contrast-enhanced images using a novel methodology. We prospectively enrolled 40 patients who underwent stress echocardiography with continuous intravenous infusion of SonoVue for the assessment of myocardial perfusion imaging with flash replenishment technique. We compared longitudinal strain (Lε) values, assessed with a vendor-independent software (2D CPA), on 68 resting contrast-enhanced and 68 resting noncontrast recordings. Strain analysis on contrast recordings was evaluated in the first cardiac cycles after the flash. Tracking of contrast images was deemed feasible in all subjects and in all views. Contrast administration improved image quality and increased the number of segments used for deformation analysis. Lε of noncontrast and contrast-enhanced images were statistically different (-18.8 ± 4.5% and -22.8 ± 5.4%, respectively; P < 0.001), but their correlation was good (ICC 0.65, 95%CI 0.42-0.78). Patients with resting wall-motion abnormalities showed lower Lε values on contrast recordings (-18.6 ± 6.0% vs. -24.2 ± 5.5%, respectively; P < 0.01). Intra-operator and inter-operator reproducibility was good for both noncontrast and contrast images with no statistical differences. Our study shows that deformation analysis on postflash contrast-enhanced images is feasible and reproducible. Therefore, it would be possible to perform a simultaneous evaluation of wall-motion abnormalities, volumes, ejection fraction, perfusion defects, and cardiac deformation on the same contrast recording. © 2016, Wiley Periodicals, Inc.

  6. Intraperitoneal onlay mesh reinforcement of the abdominal wall: a new surgical option for treatment of anterior cutaneous nerve entrapment syndrome-a retrospective cohort analysis of 30 consecutive patients.

    PubMed

    Stirler, Vincent M A; Raymakers, Johan T F J; Rakic, Srdjan

    2016-07-01

    The aim of the study was to introduce a new surgical treatment for anterior cutaneous nerve entrapment syndrome, a frequently unrecognised disorder in the general population responsible for chronic abdominal wall pain with limited treatment options to date. We hypothesised that intraperitoneal onlay mesh reinforcement could dissipate excessive increases in intra-abdominal pressure and prevent entrapment of the neurovascular bundle. Retrospective cohort analysis was performed between September 2002 and March 2014. All consecutive patients diagnosed with anterior cutaneous nerve entrapment syndrome refractory to conservative treatment (n = 30) underwent laparoscopic intraperitoneal onlay mesh reinforcement of the painful area in the abdominal wall. Planned follow-up took place at 2, 6 and 12 weeks after surgery and at time of analysis (March 2015). Primary outcome was patients' satisfaction after treatment at short and long term (last follow-up) using a verbal rating score as measurement (1 = I am very satisfied; I never experience pain, 2 = I am satisfied; I occasionally experience some pain, 3 = I have improved but experience pain on a regular basis, 4 = I have had no result on this treatment, 5 = my pain is worse after treatment). Scores 1 and 2 were classified as success, and scores 4 and 5 as failure of the treatment. Thirty patients underwent laparoscopic intraperitoneal onlay mesh reinforcement. None were lost to follow-up (mean 54 ± 44 months, range 12-122, median 38). Short- and long-term success rates were 90 and 71 %, respectfully. Intraperitoneal onlay mesh reinforcement of the abdominal wall seems to be a promising option for the treatment of intractable anterior cutaneous nerve entrapment syndrome.

  7. Technical Note: Intrafractional changes in time lag relationship between anterior-posterior external and superior-inferior internal motion signals in abdominal tumor sites.

    PubMed

    Regmi, Rajesh; Lovelock, D Michael; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D; Goodman, Karyn A; Wu, Abraham J; Mageras, Gig S

    2015-06-01

    To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. 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. 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. 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.

  8. 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

  9. Prognostic value of high-dose dobutamine stress magnetic resonance imaging in 1,493 consecutive patients: assessment of myocardial wall motion and perfusion.

    PubMed

    Korosoglou, Grigorios; Elhmidi, Yacine; Steen, Henning; Schellberg, Dieter; Riedle, Nina; Ahrens, Johannes; Lehrke, Stephanie; Merten, Constanze; Lossnitzer, Dirk; Radeleff, Jannis; Zugck, Christian; Giannitsis, Evangelos; Katus, Hugo A

    2010-10-05

    This study sought to determine the prognostic value of wall motion and perfusion assessment during high-dose dobutamine stress (DS) cardiac magnetic resonance imaging (MRI) in a large patient cohort. DS-MRI offers the possibility to integrate myocardial perfusion and wall motion analysis in a single examination for the detection of coronary artery disease (CAD). A total of 1,493 consecutive patients with suspected or known CAD underwent DS-MRI, using a standard protocol in a 1.5-T magnetic resonance scanner. Wall motion and perfusion were assessed at baseline and during stress, and outcome data including cardiac death, nonfatal myocardial infarction ("hard events"), and "late" revascularization performed >90 days after the MR scans were collected during a 2 ± 1 year follow-up period. Fifty-three hard events, including 14 cardiac deaths and 39 nonfatal infarctions, occurred during the follow-up period, whereas 85 patients underwent "late" revascularization. Using multivariable regression analysis, an abnormal result for wall motion or perfusion during stress yielded the strongest independent prognostic value for both hard events and late revascularization, clearly surpassing that of clinical and baseline magnetic resonance parameters (for wall motion: adjusted hazard ratio [HR] of 5.9 [95% confidence interval (CI): 2.5 to 13.6] for hard events and of 3.1 [95% CI: 1.7 to 5.6] for late revascularization, and for perfusion: adjusted HR of 5.4 [95% CI: 2.3 to 12.9] for hard events and of 6.2 [95% CI: 3.3 to 11.3] for late revascularization, p < 0.001 for all). DS-MRI can accurately identify patients who are at increased risk for cardiac death and myocardial infarction, separating them from those with normal findings, who have very low risk for future cardiac events. (Prognostic Value of High Dose Dobutamine Stress Magnetic Resonance Imaging; NCT00837005). Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. Comparison between spin-orbit torques measured by domain-wall motions and harmonic measurements

    NASA Astrophysics Data System (ADS)

    Kim, Joo-Sung; Nam, Yune-Seok; Kim, Dae-Yun; Park, Yong-Keun; Park, Min-Ho; Choe, Sug-Bong

    2018-05-01

    Here we report the comparison of the spin torque efficiencies measured by three different experimental schemes for Pt/Co/X stacks with material X (= Pt, Ta, Ti, Al, Au, Pd, and Ru. 7 materials). The first two spin torque efficiencies ɛDW (1 ) and ɛDW (2 ) are quantified by the measurement of spin-torque-induced effective field for domain-wall depinning and creeping motions, respectively. The last one—longitudinal spin torque efficiency ɛL—is measured by harmonic signal measurement of the magnetization rotation with uniform magnetization configuration. The results confirm that, for all measured Pt/Co/X stacks, ɛDW (1 ) and ɛDW (2 ) are exactly consistent to each other and these two efficiencies are roughly proportional to ɛL with proportionality constant π/2, which comes from the integration over the domain-wall configuration.

  11. Comparison of method using phase-sensitive motion estimator with speckle tracking method and application to measurement of arterial wall motion

    NASA Astrophysics Data System (ADS)

    Miyajo, Akira; Hasegawa, Hideyuki

    2018-07-01

    At present, the speckle tracking method is widely used as a two- or three-dimensional (2D or 3D) motion estimator for the measurement of cardiovascular dynamics. However, this method requires high-level interpolation of a function, which evaluates the similarity between ultrasonic echo signals in two frames, to estimate a subsample small displacement in high-frame-rate ultrasound, which results in a high computational cost. To overcome this problem, a 2D motion estimator using the 2D Fourier transform, which does not require any interpolation process, was proposed by our group. In this study, we compared the accuracies of the speckle tracking method and our method using a 2D motion estimator, and applied the proposed method to the measurement of motion of a human carotid arterial wall. The bias error and standard deviation in the lateral velocity estimates obtained by the proposed method were 0.048 and 0.282 mm/s, respectively, which were significantly better than those (‑0.366 and 1.169 mm/s) obtained by the speckle tracking method. The calculation time of the proposed phase-sensitive method was 97% shorter than the speckle tracking method. Furthermore, the in vivo experimental results showed that a characteristic change in velocity around the carotid bifurcation could be detected by the proposed method.

  12. Domain wall and interphase boundary motion in (1-x)Bi(Mg 0.5 Ti 0.5 )O 3 –xPbTiO 3 near the morphotropic phase boundary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tutuncu, Goknur; Chen, Jun; Fan, Longlong

    Electric field-induced changes in the domain wall motion of (1-x)Bi(Mg 0.5Ti 0.5)O 3–xPbTiO 3 (BMT-xPT) near the morphotropic phase boundary (MPB) where x = 0.37 (BMT-37PT) and x =0.38 (BMT-38PT), are studied by means of synchrotron x-ray diffraction. Through Rietveld analysis and profile fitting, a mixture of coexisting monoclinic (Cm) and tetragonal (P4mm) phases is identified at room temperature. Extrinsic contributions to the property coefficients are evident from electric-field-induced domain wall motion in both the tetragonal and monoclinic phases, as well as through the interphase boundary motion between the two phases. Domain wall motion in the tetragonal and monoclinic phasesmore » for BMT-37PT is larger than that of BMT-38PT, possibly due to this composition's closer proximity to the MPB. Increased interphase boundary motion was also observed in BMT-37PT. Lattice strain, which is a function of both intrinsic piezoelectric strain and elastic interactions of the grains (the latter originating from domain wall and interphase boundary motion), is similar for the respective tetragonal and monoclinic phases.« less

  13. Tissue Doppler Imaging in the evaluation of abdominal aortic pulsatility: a useful tool for the neonatologist.

    PubMed

    Valerio, Enrico; Grison, Alessandra; Capretta, Anna; Golin, Rosanna; Ferrarese, Paola; Bellettato, Massimo

    2017-03-01

    Sonographic cardiac evaluation of newborns with suspected aortic coarctation (AoC) should tend to demonstrate a good phasic and pulsatile flow and the absence of pressure gradient along a normally conformed aortic arch from the modified left parasternal and suprasternal echocardiographic views; these findings, however, may not necessarily rule out a more distal coarctation in the descending aorta. For this reason, the sonographic exam of newborns with suspected AoC should always include a Doppler evaluation of abdominal aortic blood flow from the subcostal view. Occasionally, however, a clearly pulsatile Doppler flow trace in abdominal aorta may be difficult to obtain due to the bad insonation angle existing between the probe and the vessel. In such suboptimal ultrasonic alignment situation, the use of Tissue Doppler Imaging instead of classic Doppler flow imaging may reveal a preserved aortic pulsatility by sampling the aortic wall motion induced by normal flow. We propose to take advantage of the TDI pattern as a surrogate of a normal pulsatile Doppler flow trace in abdominal aorta when the latter is difficult to obtain due to malalignment with the insonated vessel.

  14. Changes in dynamic embryonic heart wall motion in response to outflow tract banding measured using video densitometry

    NASA Astrophysics Data System (ADS)

    Stovall, Stephanie; Midgett, Madeline; Thornburg, Kent; Rugonyi, Sandra

    2016-11-01

    Abnormal blood flow during early cardiovascular development has been identified as a key factor in the pathogenesis of congenital heart disease; however, the mechanisms by which altered hemodynamics induce cardiac malformations are poorly understood. This study used outflow tract (OFT) banding to model increased afterload, pressure, and blood flow velocities at tubular stages of heart development and characterized the immediate changes in cardiac wall motion due to banding in chicken embryo models with light microscopy-based video densitometry. Optical videos were used to acquire two-dimensional heart image sequences over the cardiac cycle, from which intensity data were extracted along the heart centerline at several locations in the heart ventricle and OFT. While no changes were observed in the synchronous contraction of the ventricle with banding, the peristaltic-like wall motion in the OFT was significantly affected. Our data provide valuable insight into early cardiac biomechanics and its characterization using a simple light microscopy-based imaging modality.

  15. Improvement of mesh recolonization in abdominal wall reconstruction with adipose vs. bone marrow mesenchymal stem cells in a rodent model.

    PubMed

    van Steenberghe, M; Schubert, T; Guiot, Y; Goebbels, R M; Gianello, P

    2017-08-01

    Reconstruction of muscle defects remains a challenge. Our work assessed the potential of an engineered construct made of a human acellular collagen matrix (HACM) seeded with porcine mesenchymal stem cells (MSCs) to reconstruct abdominal wall muscle defects in a rodent model. This study compared 2 sources of MSCs (bone-marrow, BMSCs, and adipose, ASCs) in vitro and in vivo for parietal defect reconstruction. Cellular viability and growth factor release (VEGF, FGF-Beta, HGF, IGF-1, TGF-Beta) were investigated under normoxic/hypoxic culture conditions. Processed and recellularized HACMs were mechanically assessed. The construct was tested in vivo in full thickness abdominal wall defect treated with HACM alone vs. HACM+ASCs or BMSCs (n=14). Tissue remodeling was studied at day 30 for neo-angiogenesis and muscular reconstruction. A significantly lower secretion of IGF was observed with ASCs vs. BMSCs under hypoxic conditions (-97.6%, p<0.005) whereas significantly higher VEGF/FGF secretions were found with ASCs (+92%, p<0.001 and +72%, p<0.05, respectively). Processing and recellularization did not impair the mechanical properties of the HACM. In vivo, angiogenesis and muscle healing were significantly improved by the HACM+ASCs in comparison to BMSCs (p<0.05) at day 30. A composite graft made of an HACM seeded with ASCs can improve muscle repair by specific growth factor release in hypoxic conditions and by in vivo remodeling (neo-angiogenesis/graft integration) while maintaining mechanical properties. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Selecting criteria for the right prosthesis in defect of the abdominal wall surgery.

    PubMed

    Mohamed, H; Ion, D; Serban, M B; Ciurea, M

    2009-01-01

    The article is debating a theme of great interest for the defect of the abdominal wall surgery--the use of biocompatible prosthesis. The surgeon is often confused by the avalanche of offers made by the mesh producers, making it mandatory for him to know very well the behavior of these alloplastic structures in the tissue environment. From this point of view, we have discussed both the physicochemical properties and the histological reaction brought by the most common type of meshes: polypropylene, polyethylene - tereftalat, polytetrafluorideethylene. This presentation brings out the minimal but mandatory criteria for any mesh to be accepted, but also the criteria that need to be taken into consideration when we try to improve the qualities of the mesh closer to the desideratum of the "ideal mesh". The main conclusion of this review is that we have to change the myth of the "ideal mesh" with "the right chosen mesh", that based on its chemical, physical, structural and biological qualities will adapt perfectly first to the patient's needs and second to the surgeon's needs.

  17. Port site endometrioma: a rare cause of abdominal wall pain following laparoscopic surgery.

    PubMed

    Siddiqui, Zohaib A; Husain, Fahd; Siddiqui, Zain; Siddiqui, Midhat

    2017-06-18

    Endometriomas are a rare cause of abdominal wall pain. We report a case of a port site endometrioma presenting with an umbilical swelling. The patient underwent a laparoscopy for pelvic endometriosis 6 months previously and presented with a swelling around her umbilical port site scar associated with cyclical pain during menses. Ultrasound scan reported a well-defined lesion in the umbilicus and MRI scanning excluded other pathology. As she was symptomatic, she underwent an exploration of the scar and excision of the endometrioma with resolution of her symptoms. Precautions should be taken to reduce the risk of endometrial seeding during laparoscopic surgery. All tissues should be removed in an appropriate retrieval bag and the pneumoperitoneum should be deflated completely before removing ports to reduce the chimney effect of tissue being forced through the port site. The diagnosis should be considered in all women of reproductive age presenting with a painful port site scar. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Predicting adverse neonatal outcomes in fetuses with abdominal wall defects using prenatal risk factors.

    PubMed

    Nicholas, Sara S; Stamilio, David M; Dicke, Jeffery M; Gray, Diana L; Macones, George A; Odibo, Anthony O

    2009-10-01

    The aim of this study was to determine whether prenatal variables can predict adverse neonatal outcomes in fetuses with abdominal wall defects. A retrospective cohort study that used ultrasound and neonatal records for all cases of gastroschisis and omphalocele seen over a 16-year period. Cases with adverse neonatal outcomes were compared with noncases for multiple candidate predictive factors. Univariable and multivariable statistical methods were used to develop the prediction models, and effectiveness was evaluated using the area under the receiver operating characteristic curve. Of 80 fetuses with gastroschisis, 29 (36%) had the composite adverse outcome, compared with 15 of 33 (47%) live neonates with omphalocele. Intrauterine growth restriction was the only significant variable in gastroschisis, whereas exteriorized liver was the only predictor in omphalocele. The areas under the curve for the prediction models with gastroschisis and omphalocele are 0.67 and 0.74, respectively. Intrauterine growth restriction and exteriorization of the liver are significant predictors of adverse neonatal outcome with gastroschisis and omphalocele.

  19. 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.

  20. Evaluation of the levels of metalloproteinsase-2 in patients with abdominal aneurysm and abdominal hernias.

    PubMed

    Antoszewska, Magdalena

    2013-05-01

    Abdominal aortic aneurysms and abdominal hernias become an important health problems of our times. Abdominal aortic aneurysm and its rupture is one of the most dangerous fact in vascular surgery. There are some theories pointing to a multifactoral genesis of these kinds of diseases, all of them assume the attenuation of abdominal fascia and abdominal aortic wall. The density and continuity of these structures depend on collagen and elastic fibers structure. Reducing the strength of the fibers may be due to changes in the extracellular matrix (ECM) by the proteolytic enzymes-matrix metalloproteinases (MMPs) that degrade extracellular matrix proteins. These enzymes play an important role in the development of many disease: malignant tumors (colon, breast, lung, pancreas), cardiovascular disease (myocardial infarction, ischemia-reperfusion injury), connective tissue diseases (Ehler-Danlos Syndrome, Marfan's Syndrome), complications of diabetes (retinopathy, nephropathy). One of the most important is matrix metalloproteinase-2 (MMP-2). The aim of the study was an estimation of the MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia, and in patients with only abdominal aortic aneurysm. The study involved 88 patients aged 42 to 89 years, including 75 men and 13 women. Patients were divided into two groups: patients with abdominal aortic aneurysm and primary abdominal hernia (45 persons, representing 51.1% of all group) and patients with only abdominal aortic aneurysm (43 persons, representing 48,9% of all group). It was a statistically significant increase in MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia compared to patients with only abdominal aortic aneurysm. It was a statistically significant increase in the prevalence of POCHP in patients with only abdominal aortic aneurysm compared to patients with abdominal aortic aneurysm and primary abdominal hernia. Statistically significant

  1. Skeletal muscle derived stem cells microintegrated into a biodegradable elastomer for reconstruction of the abdominal wall.

    PubMed

    Takanari, Keisuke; Hashizume, Ryotaro; Hong, Yi; Amoroso, Nicholas J; Yoshizumi, Tomo; Gharaibeh, Burhan; Yoshida, Osamu; Nonaka, Kazuhiro; Sato, Hideyoshi; Huard, Johnny; Wagner, William R

    2017-01-01

    A variety of techniques have been applied to generate tissue engineered constructs, where cells are combined with degradable scaffolds followed by a period of in vitro culture or direct implantation. In the current study, a cellularized scaffold was generated by concurrent deposition of electrospun biodegradable elastomer (poly(ester urethane)urea, PEUU) and electrosprayed culture medium + skeletal muscle-derived stem cells (MDSCs) or electrosprayed culture medium alone as a control. MDSCs were obtained from green fluorescent protein (GFP) transgenic rats. The created scaffolds were implanted into allogenic strain-matched rats to replace a full thickness abdominal wall defect. Both control and MDSC-integrated scaffolds showed extensive cellular infiltration at 4 and 8 wk. The number of blood vessels was higher, the area of residual scaffold was lower, number of multinucleated giant cells was lower and area of connective tissue was lower in MDSC-integrated scaffolds (p < 0.05). GFP + cells co-stained positive for VEGF. Bi-axial mechanical properties of the MDSC-microintegrated constructs better approximated the anisotropic behavior of the native abdominal wall. GFP + cells were observed throughout the scaffold at ∼5% of the cell population at 4 and 8 wk. RNA expression at 4 wk showed higher expression of early myogenic marker Pax7, and b-FGF in the MDSC group. Also, higher expression of myogenin and VEGF were seen in the MDSC group at both 4 and 8 wk time points. The paracrine effect of donor cells on host cells likely contributed to the differences found in vivo between the groups. This approach for the rapid creation of highly-cellularized constructs with soft tissue like mechanics offers an attractive methodology to impart cell-derived bioactivity into scaffolds providing mechanical support during the healing process and might find application in a variety of settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Qualitative and quantitative evaluation of rigid and deformable motion correction algorithms using dual-energy CT images in view of application to CT perfusion measurements in abdominal organs affected by breathing motion

    PubMed Central

    Skornitzke, S; Fritz, F; Klauss, M; Pahn, G; Hansen, J; Hirsch, J; Grenacher, L; Kauczor, H-U

    2015-01-01

    Objective: To compare six different scenarios for correcting for breathing motion in abdominal dual-energy CT (DECT) perfusion measurements. Methods: Rigid [RRComm(80 kVp)] and non-rigid [NRComm(80 kVp)] registration of commercially available CT perfusion software, custom non-rigid registration [NRCustom(80 kVp], demons algorithm) and a control group [CG(80 kVp)] without motion correction were evaluated using 80 kVp images. Additionally, NRCustom was applied to dual-energy (DE)-blended [NRCustom(DE)] and virtual non-contrast [NRCustom(VNC)] images, yielding six evaluated scenarios. After motion correction, perfusion maps were calculated using a combined maximum slope/Patlak model. For qualitative evaluation, three blinded radiologists independently rated motion correction quality and resulting perfusion maps on a four-point scale (4 = best, 1 = worst). For quantitative evaluation, relative changes in metric values, R2 and residuals of perfusion model fits were calculated. Results: For motion-corrected images, mean ratings differed significantly [NRCustom(80 kVp) and NRCustom(DE), 3.3; NRComm(80 kVp), 3.1; NRCustom(VNC), 2.9; RRComm(80 kVp), 2.7; CG(80 kVp), 2.7; all p < 0.05], except when comparing NRCustom(80 kVp) with NRCustom(DE) and RRComm(80 kVp) with CG(80 kVp). NRCustom(80 kVp) and NRCustom(DE) achieved the highest reduction in metric values [NRCustom(80 kVp), 48.5%; NRCustom(DE), 45.6%; NRComm(80 kVp), 29.2%; NRCustom(VNC), 22.8%; RRComm(80 kVp), 0.6%; CG(80 kVp), 0%]. Regarding perfusion maps, NRCustom(80 kVp) and NRCustom(DE) were rated highest [NRCustom(80 kVp), 3.1; NRCustom(DE), 3.0; NRComm(80 kVp), 2.8; NRCustom(VNC), 2.6; CG(80 kVp), 2.5; RRComm(80 kVp), 2.4] and had significantly higher R2 and lower residuals. Correlation between qualitative and quantitative evaluation was low to moderate. Conclusion: Non-rigid motion correction improves spatial alignment of the target region and fit of CT

  3. Suprascarpal fat pad thickness may predict venous drainage patterns in abdominal wall flaps.

    PubMed

    Bast, John; Pitcher, Austin A; Small, Kevin; Otterburn, David M

    2016-02-01

    Abdominal wall flaps are routinely used in reconstructive procedures. In some patients inadequate venous drainage from the deep vein may cause fat necrosis or flap failure. Occasionally the superficial inferior epigastric vessels (SIEV) are of sufficient size to allow for microvascular revascularization. This study looked at the ratio of the sub- and suprascarpal fat layers, the number of deep system perforators, and SIEV diameter to determine any correlation of the fat topography and SIEV. 50 abdominal/pelvic CT angiograms (100 hemiabdomens) were examined in women aged 34-70 years for number of perforators, SIEV diameter, and fat pad thickness above and below Scarpa's fascia. Data was analyzed using multivariate model. The average suprascarpal and subscarpal layers were 18.6 ± 11.5 mm and 6.2 ± 7.2 mm thick, respectively. The average SIEV diameter was 2.06 ± 0.81 mm and the average number of perforators was 2.09 ± 1.03 per hemiabdomen. Hemiabdomens with suprascarpal thickness>23 mm had greater SIEV diameter [2.69 mm vs. 1.8 mm (P < 0.0001)] The fat layer thickness did not correlate with the number of perforators. Neither subscarpal fat thickness nor suprascarpal-to-subscarpal fat layer thickness correlated significantly with SIEV caliber or number of perforators in multivariate model. Suprascarpal fat pad thicker than 23 mm had larger SIEVs irrespective of the number of deep system perforators. This may indicate a cohort of patients at risk of venous congestion from poor venous drainage if only the deep system is revascularized. We recommend harvesting the SIEV in patients with suprascarpal fat pad >23 mm to aid in superficial drainage. © 2015 Wiley Periodicals, Inc.

  4. Treatment by ultrasound-guided local infiltration in adhesion-related abdominal pain and intractable hiccups: A case report.

    PubMed

    Zhu, Dan; Gu, Zhi-Yong; Lin, Chia-Shiang; Nie, Fa-Chuan; Cui, Jian

    2018-04-01

    Abdominal pain and hiccups secondary to intra-abdominal adhesion are surgical complications that are often treated by painkillers and secondary surgeries with an unsatisfactory therapeutic effect. This study presents a new treatment method that uses ultrasound-guided local infiltration in peritoneal and abdominal wall adhesions in patients with hiccups and abdominal pain. A 62-year-old patient presented to our hospital with a history of intractable hiccups and abdominal pain for 30 years. Her abdominal examination revealed a scar with an approximate length of 10 cm on the abdominal umbilical plane; pressing the right scar area could simultaneously induce abdominal pain and hiccups. Intraperitoneal computed tomography examination clearly demonstrated that the bowel had no obvious expansion. Ultrasonographic examination found that peritoneal motility below the normal peritoneal adhesion regions was significantly slower than in the normal regions. The diagnosis of chronic postoperative pain syndrome was clear. The symptoms were significantly alleviated by a successful treatment with ultrasound-guided local infiltration in the peritoneal and abdominal wall scar adhesions. After 3 stages of hospitalization and 1 year of follow-up, the patient's abdominal wall pain was relieved by approximately 80% and hiccups were relieved by approximately 70%. The above treatment is a useful option for managing abdominal adhesion and accompanying pain or hiccups resulting from abdominal surgery. This method could ease the psychological and economic burden of patients and improve their quality of life.

  5. A Relation Between Near-Wall Particle-Hemodynamics and Onset of Thrombus Formation in Abdominal Aortic Aneurysms

    PubMed Central

    Basciano, C.; Kleinstreuer, C.; Hyun, S.; Finol, E. A.

    2014-01-01

    A novel computational particle-hemodynamics analysis of key criteria for the onset of an intraluminal thrombus (ILT) in a patient-specific abdominal aortic aneurysm (AAA) is presented. The focus is on enhanced platelet and white blood cell residence times as well as their elevated surface-shear loads in near-wall regions of the AAA sac. The generalized results support the hypothesis that a patient's AAA geometry and associated particle-hemodynamics have the potential to entrap activated blood particles, which will play a role in the onset of ILT. Although the ILT history of only a single patient was considered, the modeling and simulation methodology provided allow for the development of an efficient computational tool to predict the onset of ILT formation in complex patient-specific cases. PMID:21373952

  6. Magnetic guidance versus manual control: comparison of radiofrequency lesion dimensions and evaluation of the effect of heart wall motion in a myocardial phantom.

    PubMed

    Bhaskaran, Abhishek; Barry, M A Tony; Al Raisi, Sara I; Chik, William; Nguyen, Doan Trang; Pouliopoulos, Jim; Nalliah, Chrishan; Hendricks, Roger; Thomas, Stuart; McEwan, Alistair L; Kovoor, Pramesh; Thiagalingam, Aravinda

    2015-10-01

    Magnetic navigation system (MNS) ablation was suspected to be less effective and unstable in highly mobile cardiac regions compared to radiofrequency (RF) ablations with manual control (MC). The aim of the study was to compare the (1) lesion size and (2) stability of MNS versus MC during irrigated RF ablation with and without simulated mechanical heart wall motion. In a previously validated myocardial phantom, the performance of Navistar RMT Thermocool catheter (Biosense Webster, CA, USA) guided with MNS was compared to manually controlled Navistar irrigated Thermocool catheter (Biosense Webster, CA, USA). The lesion dimensions were compared with the catheter in inferior and superior orientation, with and without 6-mm simulated wall motion. All ablations were performed with 40 W power and 30 ml/ min irrigation for 60 s. A total of 60 ablations were performed. The mean lesion volumes with MNS and MC were 57.5 ± 7.1 and 58.1 ± 7.1 mm(3), respectively, in the inferior catheter orientation (n = 23, p = 0.6), 62.8 ± 9.9 and 64.6 ± 7.6 mm(3), respectively, in the superior catheter orientation (n = 16, p = 0.9). With 6-mm simulated wall motion, the mean lesion volumes with MNS and MC were 60.2 ± 2.7 and 42.8 ± 8.4 mm(3), respectively, in the inferior catheter orientation (n = 11, p = <0.01*), 74.1 ± 5.8 and 54.2 ± 3.7 mm(3), respectively, in the superior catheter orientation (n = 10, p = <0.01*). During 6-mm simulated wall motion, the MC catheter and MNS catheter moved 5.2 ± 0.1 and 0 mm, respectively, in inferior orientation and 5.5 ± 0.1 and 0 mm, respectively, in the superior orientation on the ablation surface. The lesion dimensions were larger with MNS compared to MC in the presence of simulated wall motion, consistent with greater catheter stability. However, similar lesion dimensions were observed in the stationary model.

  7. Interfraction variation in lung tumor position with abdominal compression during stereotactic body radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mampuya, Wambaka Ange; Nakamura, Mitsuhiro; Matsuo, Yukinori

    2013-09-15

    Purpose: To assess the effect of abdominal compression on the interfraction variation in tumor position in lung stereotactic body radiotherapy (SBRT) using cone-beam computed tomography (CBCT) in a larger series of patients with large tumor motion amplitude.Methods: Thirty patients with lung tumor motion exceeding 8 mm who underwent SBRT were included in this study. After translational and rotational initial setup error was corrected based on bone anatomy, CBCT images were acquired for each fraction. The residual interfraction variation was defined as the difference between the centroid position of the visualized target in three dimensions derived from CBCT scans and thosemore » derived from averaged intensity projection images. The authors compared the magnitude of the interfraction variation in tumor position between patients treated with [n= 16 (76 fractions)] and without [n= 14 (76 fractions)] abdominal compression.Results: The mean ± standard deviation (SD) of the motion amplitude in the longitudinal direction before abdominal compression was 19.9 ± 7.3 (range, 10–40) mm and was significantly (p < 0.01) reduced to 12.4 ± 5.8 (range, 5–30) mm with compression. The greatest variance of the interfraction variation with abdominal compression was observed in the longitudinal direction, with a mean ± SD of 0.79 ± 3.05 mm, compared to −0.60 ± 2.10 mm without abdominal compression. The absolute values of the 95th percentile of the interfraction variation for one side in each direction were 3.97/6.21 mm (posterior/anterior), 4.16/3.76 mm (caudal/cranial), and 2.90/2.32 mm (right/left) without abdominal compression, and 2.14/5.03 mm (posterior/anterior), 3.93/9.23 mm (caudal/cranial), and 2.37/5.45 mm (right/left) with abdominal compression. An absolute interfraction variation greater than 5 mm was observed in six (9.2%) fractions without and 13 (17.1%) fractions with abdominal compression.Conclusions: Abdominal compression was effective for reducing the

  8. The internal-external respiratory motion correlation is unaffected by audiovisual biofeedback.

    PubMed

    Steel, Harry; Pollock, Sean; Lee, Danny; Keall, Paul; Kim, Taeho

    2014-03-01

    This study evaluated if an audiovisual (AV) biofeedback causes variation in the level of external and internal correlation due to its interactive intervention in natural breathing. The internal (diaphragm) and external (abdominal wall) respiratory motion signals of 15 healthy human subjects under AV biofeedback and free breathing (FB) were analyzed and measures of correlation and regularity taken. Regularity metrics (root mean square error and spectral power dispersion metric) were obtained and the correlation between these metrics and the internal and external correlation was investigated. For FB and AV biofeedback assisted breathing the mean correlations found between internal and external respiratory motion were 0.96±0.02 and 0.96±0.03, respectively. This means there is no evidence to suggest (p-value=0.88) any difference in the correlation between internal and external respiratory motion with the use of AV biofeedback. Our results confirmed the hypothesis that the internal-external correlation with AV biofeedback is the same as for free breathing. Should this correlation be maintained for patients, AV biofeedback can be implemented in the clinic with confidence as regularity improvements using AV biofeedback with an external signal will be reflected in increased internal motion regularity.

  9. Anterior Cutaneous Nerve Entrapment Syndrome in a Pediatric Patient Previously Diagnosed With Functional Abdominal Pain: A Case Report.

    PubMed

    DiGiusto, Matthew; Suleman, M-Irfan

    2018-03-23

    Chronic abdominal pain is common in children and adolescents but challenging to diagnose, because practitioners may be concerned about missing serious occult disease. Abdominal wall pain is an often ignored etiology for chronic abdominal pain. Anterior cutaneous nerve entrapment syndrome causes abdominal wall pain but is frequently overlooked. Correctly diagnosing patients with anterior cutaneous nerve entrapment syndrome is important because nerve block interventions are highly successful in the remittance of pain. Here, we present the case of a pediatric patient who received a diagnosis of functional abdominal pain but experienced pain remittance after receiving a trigger-point injection and transverse abdominis plane block.

  10. A novel nonoperative approach to abdominal compartment syndrome after abdominal wall reconstruction.

    PubMed

    Hasan, Zeenat R; Sorensen, G Brent

    2013-01-01

    Intraabdominal hypertension and abdominal compartment syndrome have been increasingly recognized as significant causes of morbidity and mortality in both medical and surgical patients. The gold standard remains surgical intervention; however, nonoperative approaches have been investigated less. Here, we describe the successful treatment of a severe acute case by intubation, nasogastric decompression, and paralysis--a novel approach not previously described in the literature. After the patient underwent laparoscopic bilateral component separation and repair of a large recurrent ventral hernia with a 20 30-cm Strattice mesh (LifeCell Corp, Branchburg, NJ), acute renal failure developed within 12 hours postoperatively, and was associated with oliguria, hyperkalemia, and elevated peak airway and bladder pressures. The patient was treated nonoperatively with intubation, nasogastric tube decompression, and paralysis with a vecuronium drip. Rapid reversal was seen, avoiding further surgery. Within 2 hours after intubation and paralysis, our patient's urine output improved dramatically with an initial diuresis of approximately 1 L, his bladder pressures decreased, and within 12 hours his creatinine level had normalized. Although surgical intervention has traditionally been thought of as the most effective--and thus the gold standard--for abdominal compartment syndrome, this preliminary experience demonstrates nonoperative management as highly efficacious, with the added benefit of decreased morbidity. Therefore, nonoperative management could be considered first-line therapy, with laparotomy reserved for refractory cases only. This suggests a more complex pathology than the traditional teaching of congestion and edema alone.

  11. The role of intraluminal thrombus on oxygen transport in abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Madhavan, Sudharsan; Cherry Kemmerling, Erica

    2017-11-01

    Abdominal aortic aneurysm is ranked as the 13th leading cause of death in the United States. The presence of intraluminal thrombus is thought to cause hypoxia in the vessel wall eventually aggravating the condition. Our work investigates oxygen transport and consumption in a patient-specific model of an abdominal aortic aneurysm. The model includes intraluminal thrombus and consists of the abdominal aorta, renal arteries, and iliac arteries. Oxygen transport to and within the aortic wall layer was modeled, accounting for oxygen consumption and diffusion. Flow and transport in the lumen layer were modeled using coupled Navier-Stokes and scalar transport equations. The thrombus layer was assumed to be biomechanically inactive but permeable to oxygen transport in accordance with previously-measured diffusion coefficients. Plots of oxygen concentration through the layers illustrating reduced oxygen supply to the vessel walls in parts of the model that include thrombus will be presented.

  12. 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

    2016-07-05

    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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. The effect of TISSEEL fibrin sealant on seroma formation following complex abdominal wall hernia repair: a single institutional review and derived cost analysis.

    PubMed

    Azoury, S C; Rodriguez-Unda, N; Soares, K C; Hicks, C W; Baltodano, P A; Poruk, K E; Hu, Q L; Cooney, C M; Cornell, P; Burce, K; Eckhauser, F E

    2015-12-01

    The authors evaluated the ability of a fibrin sealant (TISSEEL™: Baxter Healthcare Corp, Deerfield, IL, USA) to reduce the incidence of post-operative seroma following abdominal wall hernia repair. We performed a 4-year retrospective review of patients undergoing abdominal wall hernia repair, with and without TISSEEL, by a single surgeon (FEE) at The Johns Hopkins Hospital. Demographics, surgical risk factors, operative data and 30-day outcomes, including wound complications and related interventions, were compared. The quantity and cost of Tisseel per case was reviewed. A total of 250 patients were evaluated: 127 in the TISSEEL group and 123 in the non-TISSEEL control group. The average age for both groups was 56.6 years (P = 0.97). The majority of patients were female (TISSEEL 52.8%, non-TISSEEL 56.1%, P = 0.59) and ASA Class III (TISSEEL 56.7%, non-TISSEEL 58.5%, P = 0.40). There was no difference in the average defect size for both groups (TISSEEL 217 ± 187.6 cm(2), non-TISSEEL 161.3 ± 141.5 cm(2), P = 0.36). Surgical site occurrences occurred in 18.1% of the TISSEEL and 13% of the non-TISSEEL group (P = 0.27). There was a trend towards an increased incidence of seroma in the TISSEEL group (TISSEEL 11%, non-TISSEEL 4.9%, P = 0.07). A total of $124,472.50 was spent on TISSEEL, at an average cost of $995.78 per case. In the largest study to date, TISSEEL™ application offered no advantage for the reduction of post-operative seroma formation following complex abdominal hernia repair. Moreover, the use of this sealant was associated with significant costs.

  14. The hypertrophy of the lateral abdominal wall and quadratus lumborum is sport-specific: an MRI segmental study in professional tennis and soccer players.

    PubMed

    Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A; Dorado, Cecilia

    2013-03-01

    The aim was to determine the volume and degree of asymmetry of quadratus lumborum (QL), obliques, and transversus abdominis; the last two considered conjointly (OT), in tennis and soccer players. The volume of QL and OT was determined using magnetic resonance imaging in professional tennis and soccer players, and in non-active controls (n = 8, 14, and 6, respectively). In tennis players the hypertrophy of OT was limited to proximal segments (cephalic segments), while in soccer players it was similar along longitudinal axis. In tennis players the hypertrophy was asymmetric (18% greater volume in the non-dominant than in the dominant OT, p = 0.001), while in soccer players and controls both sides had similar volumes (p > 0.05). In controls, the non-dominant QL was 15% greater than that of the dominant (p = 0.049). Tennis and soccer players had similar volumes in both sides of QL. Tennis alters the dominant-to-non-dominant balance in the muscle volume of the lateral abdominal wall. In tennis the hypertrophy is limited to proximal segments and is greater in the non-dominant side. Soccer, however, is associated to a symmetric hypertrophy of the lateral abdominal wall. Tennis and soccer elicit an asymmetric hypertrophy of QL.

  15. Efficacy of transversus abdominis plane block with liposomal bupivacaine during open abdominal wall reconstruction.

    PubMed

    Fayezizadeh, Mojtaba; Majumder, Arnab; Neupane, Ruel; Elliott, Heidi L; Novitsky, Yuri W

    2016-09-01

    Transversus abdominis plane block (TAPb) is an analgesic adjunct used for abdominal surgical procedures. Liposomal bupivacaine (LB) demonstrates prolonged analgesic effects, up to 72 hours. We evaluated the analgesic efficacy of TAPb using LB for patients undergoing open abdominal wall reconstruction (AWR). Fifty patients undergoing AWR with TAPb using LB (TAP-group) were compared with a matched historical cohort undergoing AWR without TAPb (control group). Outcome measures included postoperative utilization of morphine equivalents, numerical rating scale pain scores, time to oral narcotics, and length of stay (LOS). Cohorts were matched demographically. No complications were associated with TAPb or LB. TAP-group evidenced significantly reduced narcotic requirements on operative day (9.5 mg vs 16.5 mg, P = .004), postoperative day (POD) 1 (26.7 mg vs 39.5 mg, P = .01) and POD2 (29.6 mg vs 40.7 mg, P = .047) and pain scores on operative day (5.1 vs 7.0, P <.001), POD1 (4.2 vs 5.5, P = .002), and POD2 (3.9 vs 4.8, P = .04). In addition, TAP-group demonstrated significantly shorter time to oral narcotics (2.7 days vs 4.0 days, P <.001) and median LOS (5.2 days vs 6.8 days, P = .004). TAPb with LB demonstrated significant reductions in narcotic consumption and improved pain control. TAPb allowed for earlier discontinuation of intravenous narcotics and shorter LOS. Intraoperative TAPb with LB appears to be an effective adjunct for perioperative analgesia in patients undergoing open AWR. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. On the effect of computed tomography resolution to distinguish between abdominal aortic aneurysm wall tissue and calcification: A proof of concept.

    PubMed

    Barrett, H E; Cunnane, E M; O Brien, J M; Moloney, M A; Kavanagh, E G; Walsh, M T

    2017-10-01

    The purpose of this study is to determine the optimal target CT spatial resolution for accurately imaging abdominal aortic aneurysm (AAA) wall characteristics, distinguishing between tissue and calcification components, for an accurate assessment of rupture risk. Ruptured and non-ruptured AAA-wall samples were acquired from eight patients undergoing open surgical aneurysm repair upon institutional review board approval and informed consent was obtained from all patients. Physical measurements of AAA-wall cross-section were made using scanning electron microscopy. Samples were scanned using high resolution micro-CT scanning. A resolution range of 15.5-155μm was used to quantify the influence of decreasing resolution on wall area measurements, in terms of tissue and calcification. A statistical comparison between the reference resolution (15.5μm) and multi-detector CT resolution (744μm) was also made. Electron microscopy examination of ruptured AAAs revealed extremely thin outer tissue structure <200μm in radial distribution which is supporting the aneurysm wall along with large areas of adjacent medial calcifications far greater in area than the tissue layer. The spatial resolution of 155μm is a significant predictor of the reference AAA-wall tissue and calcification area measurements (r=0.850; p<0.001; r=0.999; p<0.001 respectively). The tissue and calcification area at 155μm is correct within 8.8%±1.86 and 26.13%±9.40 respectively with sensitivity of 87.17% when compared to the reference. The inclusion of AAA-wall measurements, through the use of high resolution-CT will elucidate the variations in AAA-wall tissue and calcification distributions across the wall which may help to leverage an improved assessment of AAA rupture risk. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. A magnetic resonance imaging investigation of the transversus abdominis muscle during drawing-in of the abdominal wall in elite Australian Football League players with and without low back pain.

    PubMed

    Hides, Julie A; Boughen, Carly L; Stanton, Warren R; Strudwick, Mark W; Wilson, Stephen J

    2010-01-01

    Single-blinded quasi-experimental study. To investigate the ability of elite football players with and without low back pain (LBP) to voluntarily draw-in the abdominal wall. While there has been considerable debate regarding the contribution of the transversus abdominis (TrA) muscle to control the lumbar spine and pelvis, there is evidence that retraining motor control of the deep trunk muscles is commensurate with decreases in LBP. Magnetic resonance imaging (MRI) has been used to assess the TrA muscle during the draw-in maneuver, with the contraction of the TrA muscle reducing the circumference of the trunk. Impairments in performance of the draw-in maneuver have been shown in people with LBP. Forty-three elite players from a team in the Australian Football League were allocated to 3 groups: those with "no LBP," "a history of LBP but no current LBP," or "current LBP." MRI was used to image the cross-sectional area (CSA) of the trunk at the level of the L3-4 disc at the start and end of the draw-in maneuver. There was a significant decrease in the CSA of the trunk with the performance of the draw-in maneuver (P<.001). Subjects in the "no LBP" group were better able to "draw-in" the abdominal wall than subjects with current LBP (P = .015). This study provides evidence of an altered ability to draw-in the abdominal wall in footballers with current LBP. Retraining contraction of the TrA muscle may constitute one part of an exercise-therapy approach for athletes with current LBP.

  18. Strain-Encoded Cardiac Magnetic Resonance Imaging as an Adjunct for Dobutamine Stress Testing. Incremental Value to Conventional Wall Motion Analysis

    PubMed Central

    Korosoglou, Grigorios; Lossnitzer, Dirk; Schellberg, Dieter; Lewien, Antje; Wochele, Angela; Schaeufele, Tim; Neizel, Mirja; Steen, Henning; Giannitsis, Evangelos; Katus, Hugo A.; Osman, Nael F.

    2009-01-01

    Background High-dose dobutamine stress magnetic resonance imaging (DS-MRI) is safe and feasible for the diagnosis of coronary artery disease (CAD) in humans. However, the assessment of cine scans relies on the visual interpretation of regional wall motion, which is subjective. Recently, Strain-Encoded MRI (SENC) has been proposed for the direct color-coded visualization of myocardial strain. The purpose of our study was to compare the diagnostic value of SENC to that provided by conventional wall motion analysis for the detection of inducible ischemia during DS-MRI. Methods and Results Stress induced ischemia was assessed by wall motion analysis and by SENC in 101 patients with suspected or known CAD and in 17 healthy volunteers who underwent DS-MRI in a clinical 1.5T scanner. Quantitative coronary angiography deemed as the standard reference for the presence or absence of significant CAD (≥50% diameter stenosis). On a coronary vessel level, SENC detected inducible ischemia in 86/101 versus 71/101 diseased coronary vessels (p<0.01 versus cine), and showed normal strain response in 189/202 versus 194/202 vessels with <50% stenosis (p=NS versus cine). On a patient level, SENC detected inducible ischemia in 63/64 versus 55/64 patients with CAD (p<0.05 versus cine), and showed normal strain response in 32/37 versus 34/37 patients without CAD (p=NS versus cine).Quantification analysis demonstrated a significant correlation between strain rate reserve (SRreserve) and coronary artery stenosis severity (r²=0.56, p<0.001), and a cut-off value of SRreserve=1.64 deemed as a highly accurate marker for the detection of stenosis≥50% (AUC=0.96, SE=0.01, 95% CI = 0.94–0.98, p<0.001). Conclusions The direct color-coded visualization of strain on MR-images is a useful adjunct for DS-MRI, which provides incremental value for the detection of CAD compared to conventional wall motion readings on cine images. PMID:19808579

  19. 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.

  20. Temporal Fourier analysis applied to equilibrium radionuclide cineangiography. Importance in the study of global and regional left ventricular wall motion.

    PubMed

    Cardot, J C; Berthout, P; Verdenet, J; Bidet, A; Faivre, R; Bassand, J P; Bidet, R; Maurat, J P

    1982-01-01

    Regional and global left ventricular wall motion was assessed in 120 patients using radionuclide cineangiography (RCA) and contrast angiography. Functional imaging procedures based on a temporal Fourier analysis of dynamic image sequences were applied to the study of cardiac contractility. Two images were constructed by taking the phase and amplitude values of the first harmonic in the Fourier transform for each pixel. These two images aided in determining the perimeter of the left ventricle to calculate the global ejection fraction. Regional left ventricular wall motion was studied by analyzing the phase value and by examining the distribution histogram of these values. The accuracy of global ejection fraction calculation was improved by the Fourier technique. This technique increased the sensitivity of RCA for determining segmental abnormalities especially in the left anterior oblique view (LAO).

  1. Optimizing working space in laparoscopy: CT measurement of the effect of pre-stretching of the abdominal wall in a porcine model.

    PubMed

    Vlot, John; Wijnen, René; Stolker, Robert Jan; Bax, Klaas N

    2014-03-01

    Determinants of working space in minimal access surgery have not been well studied. Using computed tomography (CT) to measure volumes and linear dimensions, we are studying the effect of a number of determinants of CO2 working space in a porcine laparoscopy model. Here we report the effects of pre-stretching of the abdominal wall. Earlier we had noted an increase in CO2 pneumoperitoneum volume at repeat insufflation with an intra-abdominal pressure (IAP) of 5 mmHg after previous stepwise insufflation up to an IAP of 15 mmHg. We reviewed the data of this serendipity group; data of 16 pigs were available. In a new group of eight pigs, we also explored this effect at repeat IAPs of 10 and 15 mmHg. Volumes and linear dimensions of the CO2 pneumoperitoneum were measured on reconstructed CT images and compared between the initial and repeat insufflation runs. Previous stepwise insufflation of the abdomen with CO2 up to 15 mmHg significantly (p < 0.01) increased subsequent working-space volume at a repeat IAP of 5 mmHg by 21 %, 7 % at a repeat IAP of 10 mmHg and 3 % at a repeat IAP of 15 mmHg. The external anteroposterior diameter significantly (p < 0.01) increased by 0.5 cm (14 %) at repeat 5 mmHg. Other linear dimensions showed a much smaller change. There was no statistically significant correlation between the duration of the insufflation run and the volume increase after pre-stretching at all IAP levels. Pre-stretching of the abdominal wall allows for the same surgical-field exposure at lower IAPs, reducing the negative effects of prolonged high-pressure CO2 pneumoperitoneum on the cardiorespiratory system and microcirculation. Pre-stretching has important scientific consequences in studies addressing ways of increasing working space in that its effect may confound the possible effects of other interventions aimed at increasing working space.

  2. Frequency of Inverted Electrocardiographic T Waves (Cerebral T Waves) in Patients With Acute Strokes and Their Relation to Left Ventricular Wall Motion Abnormalities.

    PubMed

    Stone, Jeremy; Mor-Avi, Victor; Ardelt, Agnieszka; Lang, Roberto M

    2018-01-01

    Transient, symmetric, and deep inverted electrocardiogram (ECG) T waves in the setting of stroke, commonly referred to as cerebral T waves, are rare, and the underlying mechanism is unclear. Our study aimed to test the hypothesis that cerebral T waves are associated with transient cardiac dysfunction. This retrospective study included 800 patients admitted with the primary diagnosis of hemorrhagic or ischemic stroke. ECGs were examined for cerebral T waves, defined as T-wave inversion of ≥5 mm depth in ≥4 contiguous precordial leads. Echocardiograms of those meeting these criteria were examined for the presence of left ventricular (LV) wall motion abnormalities. Follow-up evaluation included both ECG and echocardiogram. Of the 800 patients, 17 had cerebral T waves on ECG (2.1%). All 17 patients had ischemic strokes, of which 11 were in the middle cerebral artery distribution (65%), and 2 were cerebellar (12%), whereas the remaining 4 involved other locations. Follow-up ECG showed resolution of the T-wave changes in all 17 patients. Of these patients, 14 (82%) had normal wall motion, and 3 had transient wall motion abnormalities (18%). Two of these patients had Takotsubo-like cardiomyopathy with apical ballooning, and the third had globally reduced LV function. Coronary angiography showed no significant disease to explain the LV dysfunction. In summary, in our cohort of patients with acute stroke, cerebral T waves were rare and occurred only in ischemic stroke. Eighteen percent of patients with cerebral T waves had significant transient wall motion abnormalities. Patients with stroke with cerebral T waves, especially in those with ischemic strokes, should be assessed for cardiac dysfunction. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Oscillatory dependence of current driven domain wall motion on current pulse length

    NASA Astrophysics Data System (ADS)

    Thomas, Luc

    2007-03-01

    The motion of domain walls (DW) in magnetic nanowires driven by spin torque from spin-polarized current is of considerable interest. Most previous work has considered the effect of dc or ˜microsecond long current pulses. Here, we show that the dynamics of DWs driven by nanosecond-long current pulses is unexpectedly complex. In particular, we show that the current driven motion of a DW, confined to a pinning site in a permalloy nanowire, exhibits an oscillatory dependence on the current pulse length with a period of just a few nanoseconds [1]. This behavior can be understood within a surprisingly straightforward one dimensional analytical model of the DW's motion. When a current pulse is applied, the DW's position oscillates within the pinning potential out of phase with the DW's out-of-plane magnetization, where the latter acts like the DW's momentum. Thus, the current driven motion of the DW is akin to a harmonic oscillator, whose frequency is determined by the ``mass'' of the DW and where the restoring force is related to the slope of the pinning potential. Remarkably, when the current pulse is turned off during phases of the DW motion when it has enough momentum, the amplitude of the oscillations can be amplified such that the DW exits the pinning potential well after the pulse is turned off. This oscillatory depinning occurs for currents smaller than the dc threshold current, and, moreover, the DW moves against the electron flow, opposite to the propagation direction above the dc threshold. These effects can be further amplified by using trains of current pulses whose lengths and separations are matched to the DW's oscillation period. In this way, we have demonstrated a five fold reduction in the threshold current required to move a DW out of a pinning site, making this effect potentially important for technological applications. [1] L. Thomas, M. Hayashi, X. Jiang, R. Moriya, C. Rettner and S.S.P. Parkin, Nature 443, 197 (2006).

  4. SU-E-J-48: Development of An Abdominal Compression Device for Respiratory Correlated Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, T; Kang, S; Kim, D

    Purpose: The aim of this study is to develop the abdominal compression device which could control pressure level according to the abdominal respiratory motion and evaluate its feasibility. Methods: In this study, we focused on developing the abdominal compression device which could control pressure level at any point of time so the developed device is possible to use a variety of purpose (gating technique or respiratory training system) while maintaining the merit of the existing commercial device. The compression device (air pad form) was designed to be able to compress the front and side of abdomen and the pressure levelmore » of the abdomen is controlled by air flow. Pressure level of abdomen (air flow) was determined using correlation data between external abdominal motion and respiratory volume signal measured by spirometer. In order to verify the feasibility of the device, it was necessary to confirm the correlation between the abdominal respiratory motion and respiratory volume signal and cooperation with respiratory training system also checked. Results: In the previous study, we could find that the correlation coefficient ratio between diaphragm and respiratory volume signal measured by spirometer was 0.95. In this study, we confirmed the correlation between the respiratory volume signal and the external abdominal motion measured by belt-transducer (correlation coefficient ratio was 0.92) and used the correlated respiratory volume data as an abdominal pressure level. It was possible to control the pressure level with negligible time delay and respiratory volume data based guiding waveforms could be properly inserted into the respiratory training system. Conclusion: Through this feasibility study, we confirmed the correlation between the respiratory volume signal and the external abdominal motion. Also initial assessment of the device and its compatibility with the respiratory training system were verified. Further study on application in respiratory

  5. Aging near the wall in colloidal glasses

    NASA Astrophysics Data System (ADS)

    Cao, Cong; Huang, Xinru; Weeks, Eric

    In a colloidal glass system, particles move slower as sample ages. In addition, their motions may be affected by their local structure, and this structure will be different near a wall. We examine how the aging process near a wall differs from that in the bulk of the sample. In particular, we use a confocal microscope to observe 3D motion in a bidisperse colloidal glass sample. We find that flat walls induce the particles to organize into layers. The aging process behaves differently near the boundary, especially within the first three layers. Particle motion near the wall is noticeably slower but also changes less dramatically with age. We compare and contrast aging seen in samples with flat and rough walls.

  6. Brownian motion as a new probe of wettability.

    PubMed

    Mo, Jianyong; Simha, Akarsh; Raizen, Mark G

    2017-04-07

    Understanding wettability is crucial for optimizing oil recovery, semiconductor manufacturing, pharmaceutical industry, and electrowetting. In this letter, we study the effects of wettability on Brownian motion. We consider the cases of a sphere in an unbounded fluid medium, as well as a sphere placed in the vicinity of a plane wall. For the first case, we show the effects of wettability on the statistical properties of the particles' motion, such as velocity autocorrelation, velocity, and thermal force power spectra over a large range of time scales. We also propose a new method to measure wettability based on the particles' Brownian motion. In addition, we compare the boundary effects on Brownian motion imposed by both no-slip and perfect-slip flat walls. We emphasize the surprising boundary effects on Brownian motion imposed by a perfect-slip wall in the parallel direction, such as a higher particle mobility parallel to a perfect flat wall compared to that in the absence of the wall, as well as compared to a particle near a no-slip flat wall.

  7. Abdominal stab wound protocol: prospective study documents applicability for widespread use.

    PubMed

    Rosemurgy, A S; Albrink, M H; Olson, S M; Sherman, H; Albertini, J; Kramer, R; Camps, M; Reiss, A

    1995-02-01

    Traditionally, stab wounds violating the abdominal wall fascia led to exploratory celiotomy that was often nontherapeutic. In an attempt to limit the number of nontherapeutic celiotomies (NTC), we devised a protocol to prospectively study stab wounds violating the anterior abdominal wall fascia. Through protocol, abdominal stab wounds were explored in stable adults. If the anterior fascia was violated, paracentesis and, if necessary, peritoneal lavage was undertaken in the absence of previous abdominal surgery. If evisceration was noted, it was reduced and the patient lavaged. Fascial penetration was noted in 72 patients. 46 patients underwent celiotomy: because of shock/peritonitis in 8 (2 NTC), fascial penetration with a history of previous celiotomy in 7 (5 NTC), positive paracentesis in 20 (5 NTC), or positive lavage in 10 (4 NTC). One patient underwent late celiotomy without ill-effect after a negative lavage because she subsequently developed fever and localized peritonitis (ice pick injury to cecum). Eleven patients had evisceration; nine underwent celiotomy. Patients with abdominal stab wounds can be selectively managed safely. More than one-third with fascial penetration, some with evisceration, avoided exploration. Only one patient underwent delayed celiotomy and did so without detriment. Nontherapeutic celiotomy rates were highest in patients with previous abdominal surgery who, thereby, could not undergo paracentesis/lavage; excluding these patients, the nontherapeutic celiotomy rate was 17% (11/65) for those with fascial penetration.

  8. Neurolytic transversus abdominal plane block with alcohol for long-term malignancy related pain control.

    PubMed

    Hung, Joseph C; Azam, Nyla; Puttanniah, Vinay; Malhotra, Vivek; Gulati, Amitabh

    2014-01-01

    There have been several case reports in the literature of neurolytic transversus abdominis plane (TAP) blocks being used for malignant abdominal wall pain. However, most used phenol as a neurolytic agent. We found only a single case report by Sakamoto using alcohol for TAP neurolysis. Unfortunately this patient passed away only 5 days after performance of the block. We attempt to extend upon the existing literature by describing neurolytic TAP blockade outcomes using alcohol on 3 cancer patients with metastatic disease to the abdominal wall. Two of our 3 patients had colorectal cancer invading the abdominal musculature. The third patient had a metastatic neuroendocrine nodule in the left rectus muscle. In our case series, all 3 patients had sustained and significant (greater than 50%) relief of abdominal wall pain after performing TAP neurolysis using alcohol. Ultrasound guidance was used for all blocks. The concentration of alcohol used varied from 33% to 77% between patients. Duration of relief lasted between 17 days and 6 months. Opioid use either decreased or remained relatively stable for prolonged periods of time after neurolysis. Other than one patient with transient post-procedure pain related to alcohol injection, there were no significant complications. Addition of a depo steroid for diagnostic TAP blockade prior to neurolysis did not appear to extend or provide additional analgesia. Based on our observations, TAP neurolysis using alcohol also offers a feasible option for long-term control of malignant abdominal wall pain. Further investigation is needed to determine if alcohol offers any significant advantage compared with phenol.

  9. Changes in the frequencies of abdominal wall hernias and the preferences for their repair: a multicenter national study from Turkey.

    PubMed

    Seker, Gaye; Kulacoglu, Hakan; Öztuna, Derya; Topgül, Koray; Akyol, Cihangir; Çakmak, Atıl; Karateke, Faruk; Özdoğan, Mehmet; Ersoy, Eren; Gürer, Ahmet; Zerbaliyev, Elbrus; Seker, Duray; Yorgancı, Kaya; Pergel, Ahmet; Aydın, Ibrahim; Ensari, Cemal; Bilecik, Tuna; Kahraman, İzzettin; Reis, Erhan; Kalaycı, Murat; Canda, Aras Emre; Demirağ, Alp; Kesicioğlu, Tuğrul; Malazgirt, Zafer; Gündoğdu, Haldun; Terzi, Cem

    2014-01-01

    Abdominal wall hernias are a common problem in the general population. A Western estimate reveals that the lifetime risk of developing a hernia is about 2%. As a result, hernia repairs likely comprise the most frequent general surgery operations. More than 20 million hernias are estimated to be repaired every year around the world. Numerous repair techniques have been described to date however tension-free mesh repairs are widely used today because of their low hernia recurrence rates. Nevertheless, there are some ongoing debates regarding the ideal approach (open or laparoscopic), the ideal anesthesia (general, local, or regional), and the ideal mesh (standard polypropylene or newer meshes).

  10. Twisted intra-abdominal cyst in a neonate: a surprise revelation.

    PubMed

    Mohamed, Ferzine; Telugu, Ramesh Babu; Karl, Immanuel Sampath

    2017-08-08

    We, herein, present a male neonate with an antenatally detected intra-abdominal cyst who presented at 18 days of life at which time, the ultrasound revealed a 5×4 cm cyst. Since he was asymptomatic, we planned to repeat the ultrasound a month later and operate if the cyst showed no regression. However, a week later, he presented with an acute abdomen, irritable cry and a repeat ultrasound showing a larger (8×6 cm) cystic mass with debris within. He was taken up for an emergency laparotomy. Intraoperatively, the cyst was found arising from the left lateral abdominal wall free from all structures with a twisted pedicle. Histopathology surprisingly revealed seminiferous tubules within the cyst wall with the vas deferens, thus confirming the diagnosis of a torsion of intra-abdominal testis. Hence, we emphasise the importance of examining for an undescended testis when dealing with a male neonate presenting with a cystic intra-abdominal mass. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Sci-Fri PM: Radiation Therapy, Planning, Imaging, and Special Techniques - 11: Quantification of chest wall motion during deep inspiration breast hold treatments using cine EPID images and a physics based algorithm

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alpuche Aviles, Jorge E.; VanBeek, Timothy

    Purpose: This work presents an algorithm used to quantify intra-fraction motion for patients treated using deep inspiration breath hold (DIBH). The algorithm quantifies the position of the chest wall in breast tangent fields using electronic portal images. Methods: The algorithm assumes that image profiles, taken along a direction perpendicular to the medial border of the field, follow a monotonically and smooth decreasing function. This assumption is invalid in the presence of lung and can be used to calculate chest wall position. The algorithm was validated by determining the position of the chest wall for varying field edge positions in portalmore » images of a thoracic phantom. The algorithm was used to quantify intra-fraction motion in cine images for 7 patients treated with DIBH. Results: Phantom results show that changes in the distance between chest wall and field edge were accurate within 0.1 mm on average. For a fixed field edge, the algorithm calculates the position of the chest wall with a 0.2 mm standard deviation. Intra-fraction motion for DIBH patients was within 1 mm 91.4% of the time and within 1.5 mm 97.9% of the time. The maximum intra-fraction motion was 3.0 mm. Conclusions: A physics based algorithm was developed and can be used to quantify the position of chest wall irradiated in tangent portal images with an accuracy of 0.1 mm and precision of 0.6 mm. Intra-fraction motion for patients treated with DIBH at our clinic is less than 3 mm.« less

  12. Local Nanomechanical Motion In Single Cells.

    NASA Astrophysics Data System (ADS)

    Pelling, Andrew; Gimzewski, James

    2004-03-01

    We present new evidence that the nanoscale motion of the cell wall of Saccharomyces cerevisiae exhibits local bionanomechanical motion at characteristic frequencies and which is not caused by random or Brownian processes. This motion is measured with the AFM tip which acts as a nanomechanical sensor, permitting the motion of the cell wall to be recorded as a function of time, applied force, etc. We present persuasive evidence which shows that the local nanomechanical motion is characteristic of metabolic processes taking place inside the cell. This is demonstrated by clear differences between living cells and living cells treated with a metabolic inhibitor. This inhibitor specifically targets cytochrome oxidase inside the mitochondria and inhibits ATP production. The cells observed in this study display characteristic local cell wall motion with amplitudes between 1 and 3 nm and frequencies between 500 and 1700 Hz. The motion is temperature dependant which also suggests the mechanism for the observed motion has biological origins. In addition to a stringent series of control experiments we also discuss local measurements of the cell's mechanical properties and their influence on the observed bionanomechanical motion.

  13. Fourier Transform Infrared Spectroscopic Imaging-Derived Collagen Content and Maturity Correlates with Stress in the Aortic Wall of Abdominal Aortic Aneurysm Patients.

    PubMed

    Cheheltani, Rabee; Pichamuthu, Joseph E; Rao, Jayashree; Weinbaum, Justin S; Kiani, Mohammad F; Vorp, David A; Pleshko, Nancy

    2017-03-01

    Abdominal aortic aneurysm (AAA) is a degenerative disease of the aorta characterized by severe disruption of the structural integrity of the aortic wall and its major molecular constituents. From the early stages of disease, elastin in the aorta becomes highly degraded and is replaced by collagen. Questions persist as to the contribution of collagen content, quality and maturity to the potential for rupture. Here, using our recently developed Fourier transform infrared imaging spectroscopy (FT-IRIS) method, we quantified collagen content and maturity in the wall of AAA tissues in pairs of specimens with different wall stresses. CT scans of AAAs from 12 patients were used to create finite element models to estimate stress in different regions of tissue. Each patient underwent elective repair of the AAA, and two segments of the AAA tissues from anatomic regions more proximal or distal with different wall stresses were evaluated by histology and FT-IRIS after excision. For each patient, collagen content was generally greater in the tissue location with lower wall stress, which corresponded to the more distal anatomic regions. The wall stress/collagen ratio was greater in the higher stress region compared to the lower stress region (1.01 ± 1.09 vs. 0.55 ± 0.084, p = 0.02). The higher stress region also corresponded to the location with reduced intraluminal thrombus thickness. Further, collagen maturity tended to decrease with increased collagen content (p = 0.068, R = 0.38). Together, these results suggest that an increase in less mature collagen content in AAA patients does not effectively compensate for the loss of elastin in the aortic wall, and results in a reduced capability to endure wall stresses.

  14. A dual-Kinect approach to determine torso surface motion for respiratory motion correction in PET

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Heß, Mirco, E-mail: mirco.hess@uni-muenster.de; Büther, Florian; Dawood, Mohammad

    2015-05-15

    Purpose: Respiratory gating is commonly used to reduce blurring effects and attenuation correction artifacts in positron emission tomography (PET). Established clinically available methods that employ body-attached hardware for acquiring respiration signals rely on the assumption that external surface motion and internal organ motion are well correlated. In this paper, the authors present a markerless method comprising two Microsoft Kinects for determining the motion on the whole torso surface and aim to demonstrate its validity and usefulness—including the potential to study the external/internal correlation and to provide useful information for more advanced correction approaches. Methods: The data of two Kinects aremore » used to calculate 3D representations of a patient’s torso surface with high spatial coverage. Motion signals can be obtained for any position by tracking the mean distance to a virtual camera with a view perpendicular to the surrounding surface. The authors have conducted validation experiments including volunteers and a moving high-precision platform to verify the method’s suitability for providing meaningful data. In addition, the authors employed it during clinical {sup 18}F-FDG-PET scans and exemplarily analyzed the acquired data of ten cancer patients. External signals of abdominal and thoracic regions as well as data-driven signals were used for gating and compared with respect to detected displacement of present lesions. Additionally, the authors quantified signal similarities and time shifts by analyzing cross-correlation sequences. Results: The authors’ results suggest a Kinect depth resolution of approximately 1 mm at 75 cm distance. Accordingly, valid signals could be obtained for surface movements with small amplitudes in the range of only few millimeters. In this small sample of ten patients, the abdominal signals were better suited for gating the PET data than the thoracic signals and the correlation of data

  15. On the prediction of monocyte deposition in abdominal aortic aneurysms using computational fluid dynamics.

    PubMed

    Hardman, David; Doyle, Barry J; Semple, Scott I K; Richards, Jennifer M J; Newby, David E; Easson, William J; Hoskins, Peter R

    2013-10-01

    In abdominal aortic aneurysm disease, the aortic wall is exposed to intense biological activity involving inflammation and matrix metalloproteinase-mediated degradation of the extracellular matrix. These processes are orchestrated by monocytes and rather than affecting the aorta uniformly, damage and weaken focal areas of the wall leaving it vulnerable to rupture. This study attempts to model numerically the deposition of monocytes using large eddy simulation, discrete phase modelling and near-wall particle residence time. The model was first applied to idealised aneurysms and then to three patient-specific lumen geometries using three-component inlet velocities derived from phase-contrast magnetic resonance imaging. The use of a novel, variable wall shear stress-limiter based on previous experimental data significantly improved the results. Simulations identified a critical diameter (1.8 times the inlet diameter) beyond which significant monocyte deposition is expected to occur. Monocyte adhesion occurred proximally in smaller abdominal aortic aneurysms and distally as the sac expands. The near-wall particle residence time observed in each of the patient-specific models was markedly different. Discrete hotspots of monocyte residence time were detected, suggesting that the monocyte infiltration responsible for the breakdown of the abdominal aortic aneurysm wall occurs heterogeneously. Peak monocyte residence time was found to increase with aneurysm sac size. Further work addressing certain limitations is needed in a larger cohort to determine clinical significance.

  16. A Case of Pediatric Abdominal Wall Reconstruction: Components Separation within the Austere War Environment

    PubMed Central

    Sabino, Jennifer; Kumar, Anand

    2014-01-01

    Summary: Reconstructive surgeons supporting military operations are required to definitively treat severe pediatric abdominal injuries in austere environments. The safety and efficacy of using a components separation technique to treat large ventral hernias in pediatric patients in this setting remains understudied. Components separation technique was required to achieve definitive closure in a 12-month-old pediatric patient in Kandahar, Afghanistan. Her course was complicated by an anastomotic leak after small bowel resection. Her abdominal was successfully reopened, the leak repaired, and closed primarily without incident on postinjury day 9. Abdominal trauma with a large ventral hernia requiring components separation is extremely rare. A pediatric patient treated with components separation demonstrated minimal complications, avoidance of abdominal compartment syndrome, and no mortality. PMID:25426363

  17. 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.

  18. Open and Laparo-Endoscopic Repair of Incarcerated Abdominal Wall Hernias by the Use of Biological and Biosynthetic Meshes.

    PubMed

    Fortelny, René H; Hofmann, Anna; May, Christopher; Köckerling, Ferdinand

    2016-01-01

    Although recently published guidelines recommend against the use of synthetic non-absorbable materials in cases of potentially contaminated or contaminated surgical fields due to the increased risk of infection (1, 2), the use of bio-prosthetic meshes for abdominal wall or ventral hernia repair is still controversially discussed in such cases. Bio-prosthetic meshes have been recommended due to less susceptibility for infection and the decreased risk of subsequent mesh explantation. The purpose of this review is to elucidate if there are any indications for the use of biological and biosynthetic meshes in incarcerated abdominal wall hernias based on the recently published literature. A literature search of the Medline database using the PubMed search engine, using the keywords returned 486 articles up to June 2015. The full text of 486 articles was assessed and 13 relevant papers were identified including 5 retrospective case cohort studies, 2 case-controlled studies, and 6 case series. The results of Franklin et al. (3-5) included the highest number of biological mesh repairs (Surgisis(®)) by laparoscopic IPOM in infected fields, which demonstrated a very low incidence of infection and recurrence (0.7 and 5.2%). Han et al. (6) reported in his retrospective study, the highest number of treated patients due to incarcerated hernias by open approach using acellular dermal matrix (ADM(®)) with very low rate of infection as well as recurrences (1.6 and 15.9%). Both studies achieved acceptable outcome in a follow-up of at least 3.5 years compared to the use of synthetic mesh in this high-risk population (7). Currently, there is a very limited evidence for the use of biological and biosynthetic meshes in strangulated hernias in either open or laparo-endoscopic repair. Finally, there is an urgent need to start with randomized controlled comparative trials as well as to support registries with data to achieve more knowledge for tailored indication for the use of

  19. What Do We Know About Component Separation Techniques for Abdominal Wall Hernia Repair?

    PubMed

    Scheuerlein, Hubert; Thiessen, Andreas; Schug-Pass, Christine; Köckerling, Ferdinand

    2018-01-01

    The component separation technique (CST) was introduced to abdominal wall reconstruction to treat large, complex hernias. It is very difficult to compare the published findings because of the vast number of technical modifications to CST as well as the heterogeneity of the patient population operated on with this technique. The main focus of the literature search conducted up to August 2017 in Medline and PubMed was on publications reporting comparative findings as well as on systematic reviews in order to formulate statements regarding the various CSTs. CST without mesh should no longer be performed because of too high recurrence rates. Open anterior CST has too high a surgical site occurrence rate and henceforth should only be conducted as endoscopic and perforator sparing anterior CST. Open posterior CST and posterior CST with transversus abdominis release (TAR) produce better results than open anterior CST. To date, no significant differences have been found between endoscopic anterior, perforator sparing anterior CST and posterior CST with transversus abdominis release. Robot-assisted posterior CST with TAR is the latest, very promising alternative. The systematic use of biologic meshes cannot be recommended for CST. CST should always be performed with mesh as endoscopic or perforator sparing anterior or posterior CST. Robot-assisted posterior CST with TAR is the latest development.

  20. 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

  1. A Rare Case of Giant Basal Cell Carcinoma of the Abdominal Wall: Excision and Immediate Reconstruction with a Pedicled Deep Inferior Epigastric Artery Perforator (DIEP) Flap.

    PubMed

    Di Lorenzo, Sara; Zabbia, Giovanni; Corradino, Bartolo; Tripoli, Massimiliano; Pirrello, Roberto; Cordova, Adriana

    2017-12-04

    BACKGROUND Basal cell carcinoma (BCC) greater than 5 cm in diameter is called giant basal cell carcinoma (GBCC), or super giant basal cell carcinoma if it has a diameter larger than 20 cm. Giant BCC only accounts for 0.5% of BCCs and super giant BCC is exceedingly rare. On account of their rarity, there are no established guidelines for GBCC treatment. CASE REPORT We describe a peculiar case of an 82-year-old woman with a GBCC carcinoma of the lower abdominal wall. The tumor was surgically removed with ipsilateral inguinal lymph nodes and the abdominal wall was reconstructed immediately with a pedicled deep inferior epigastric artery perforator (DIEP) flap. CONCLUSIONS Treatment of giant basal cell carcinoma is often difficult, especially in elderly patients with poor general health and multiple pathologies. The pedicled DIEP flap is rotated to cover the loss of substance without tension, and it is easy to harvest and transfer. This flap allowed a good result without local or systemic complication. We present this report as a reminder of the occasional occurrence of extremely aggressive BCCs. We believe that, especially for rare tumors like these, it is very useful for the entire scientific community to publish these cases and the therapeutic strategies used to treat them.

  2. Repair of Postoperative Abdominal Hernia in a Child with Congenital Omphalocele Using Porcine Dermal Matrix

    PubMed Central

    Mylona, E.; Tsakalidis, C.; Spyridakis, I.; Mitsiakos, G.; Karagianni, P.

    2016-01-01

    Introduction. Incisional hernias are a common complication appearing after abdominal wall defects reconstruction, with omphalocele and gastroschisis being the most common etiologies in children. Abdominal closure of these defects represents a real challenge for pediatric surgeons with many surgical techniques and various prosthetic materials being used for this purpose. Case Report. We present a case of repair of a postoperative ventral hernia occurring after congenital omphalocele reconstruction in a three-and-a-half-year-old child using an acellular, sterile, porcine dermal mesh. Conclusion. Non-cross-linked acellular porcine dermal matrix is an appropriate mesh used for the reconstruction of abdominal wall defects and their postoperative complications like large ventral hernias with success and preventing their recurrence. PMID:27110247

  3. Repair of Postoperative Abdominal Hernia in a Child with Congenital Omphalocele Using Porcine Dermal Matrix.

    PubMed

    Lambropoulos, V; Mylona, E; Mouravas, V; Tsakalidis, C; Spyridakis, I; Mitsiakos, G; Karagianni, P

    2016-01-01

    Introduction. Incisional hernias are a common complication appearing after abdominal wall defects reconstruction, with omphalocele and gastroschisis being the most common etiologies in children. Abdominal closure of these defects represents a real challenge for pediatric surgeons with many surgical techniques and various prosthetic materials being used for this purpose. Case Report. We present a case of repair of a postoperative ventral hernia occurring after congenital omphalocele reconstruction in a three-and-a-half-year-old child using an acellular, sterile, porcine dermal mesh. Conclusion. Non-cross-linked acellular porcine dermal matrix is an appropriate mesh used for the reconstruction of abdominal wall defects and their postoperative complications like large ventral hernias with success and preventing their recurrence.

  4. Evaluation of left ventricular wall motion and function in patients with previous myocardial infarction by three-dimensional 99mTc-HSAD multigated cardiac pool imaging.

    PubMed

    Yamazaki, J; Naitou, K; Ishida, S; Uno, N; Saisho, K; Munakata, T; Morishita, T; Takano, M; Yabe, Y

    1997-05-01

    To evaluate left ventricular (LV) wall motion stereoscopically from all directions and to calculate the LV volume by three-dimensional (3D) imaging. 99mTc-DTPA human serum albumin-multigated cardiac pool-single photon emission computed tomography (99mTc-MUGA-SPECT) was performed. A new data processing program was developed with the Application Visualization System-Medical Viewer (AVS-MV) based on images obtained from 99mTc-MUGA-SPECT. In patients with previous myocardial infarction, LV function and LV wall motion were evaluated by 3D-99mTc-MUGA imaging. The LV end-diastolic volume (LVEDV) and end-systolic volume (LVESV) were obtained from 3D-99mTc-MUGA images by the surface rendering method, and the left ventricular ejection fraction (LVEF) was calculated at thresholds of 35% (T1), 40% (T2), 45% (T3), and 50% (T4). There was a strong correlation between the LV volume calculated by 3D-99mTc-MUGA imaging at a threshold of 40% and that determined by contrast left ventriculography (LVEDV: 194.7 +/- 36.0 ml vs. 198.7 +/- 39.1 ml, r = 0.791, p < 0.001; LVESV: 91.6 +/- 44.5 ml vs. 93.3 +/- 41.3 ml, r = 0.953, p < 0.001), respectively. When compared with the LVEF data obtained by left ventriculography, significant correlations were found for 3D images reconstructed at each threshold (T1: r = 0.966; T2: r = 0.962; T3: r = 0.958; and T4: r = 0.955). In addition, when LV wall motion obtained by 3D-99mTc-MUGA imaging (LAT and LAO views) was compared with the results obtained by left ventriculography (RAO and LAO views), there was good agreement. 3D-99mTc-MUGA imaging was superior in allowing evaluation of LV wall motion in all directions and in assessment of LV function, since data acquisition and image reconstruction could be done within a short time with the three-detector imaging system and AVS-MV. This method appears to be very useful for the observation of both LV wall motion and LV function in patients with ischemic heart disease, because it is a noninvasive examination.

  5. Comparison of Quantitative Wall Motion Analysis and Strain For Detection Of Coronary Stenosis With Three-Dimensional Dobutamine Stress Echocardiography

    PubMed Central

    Parker, Katherine M.; Clark, Alexander P.; Goodman, Norman C.; Glover, David K.; Holmes, Jeffrey W.

    2015-01-01

    Background Quantitative analysis of wall motion from three-dimensional (3D) dobutamine stress echocardiography (DSE) could provide additional diagnostic information not available from qualitative analysis. In this study we compare the effectiveness of 3D fractional shortening (3DFS), a measure of wall motion computed from 3D echocardiography (3DE), to strain and strain rate measured with sonomicrometry for detecting critical stenoses during DSE. Methods Eleven open-chest dogs underwent DSE both with and without a critical stenosis. 3DFS was measured from 3DE images acquired at peak stress. 3DFS was normalized by subtracting average 3DFS during control peak stress (Δ3DFS). Strains in the perfusion defect (PD) were measured from sonomicrometry, and PD size and location were measured with microspheres. Results A Δ3DFS abnormality indicated the presence of a critical stenosis with high sensitivity and specificity (88% and 100%, respectively), and Δ3DFS abnormality size correlated with PD size (R2=0.54). The sensitivity and specificity for Δ3DFS was similar to that for area strain (88%, 100%) and circumferential strain and strain rate (88%, 92% and 88%, 86%, respectively), while longitudinal strain and strain rate were less specific. Δ3DFS correlated significantly with both coronary flow reserve (R2=0.71) and PD size (R2=0.97), while area strain correlated with PD size only (R2=0.67), and other measures were not significantly correlated with flow reserve or PD size. Conclusion Quantitative wall motion analysis using Δ3DFS is effective for detecting critical stenoses during DSE, performing similarly to 3D strain, and provides potentially useful information on the size and location of a perfusion defect. PMID:24815588

  6. Changes in the Frequencies of Abdominal Wall Hernias and the Preferences for Their Repair: A Multicenter National Study From Turkey

    PubMed Central

    Şeker, Gaye; Kulacoglu, Hakan; Öztuna, Derya; Topgül, Koray; Akyol, Cihangir; Çakmak, Atıl; Karateke, Faruk; Özdoğan, Mehmet; Ersoy, Eren; Gürer, Ahmet; Zerbaliyev, Elbrus; Seker, Duray; Yorgancı, Kaya; Pergel, Ahmet; Aydın, İbrahim; Ensari, Cemal; Bilecik, Tuna; Kahraman, İzzettin; Reis, Erhan; Kalaycı, Murat; Canda, Aras Emre; Demirağ, Alp; Kesicioğlu, Tuğrul; Malazgirt, Zafer; Gündoğdu, Haldun; Terzi, Cem

    2014-01-01

    Abdominal wall hernias are a common problem in the general population. A Western estimate reveals that the lifetime risk of developing a hernia is about 2%.1–3 As a result, hernia repairs likely comprise the most frequent general surgery operations. More than 20 million hernias are estimated to be repaired every year around the world.4 Numerous repair techniques have been described to date however tension-free mesh repairs are widely used today because of their low hernia recurrence rates. Nevertheless, there are some ongoing debates regarding the ideal approach (open or laparoscopic),5,6 the ideal anesthesia (general, local, or regional),7,8 and the ideal mesh (standard polypropylene or newer meshes).9,10 PMID:25216417

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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 moremore » 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

  8. Tissue factor levels and the fibrinolytic system in thin and thick intraluminal thrombus and underlying walls of abdominal aortic aneurysms.

    PubMed

    Siennicka, Aldona; Zuchowski, Marta; Kaczmarczyk, Mariusz; Cnotliwy, Miłosław; Clark, Jeremy Simon; Jastrzębska, Maria

    2018-03-20

    The hemostatic system cooperates with proteolytic degradation in processes allowing abdominal aortic aneurysm (AAA) formation. In previous studies, it has been suggested that aneurysm rupture depends on intraluminal thrombus (ILT) thickness, which varies across each individual aneurysm. We hypothesized that hemostatic components differentially accumulate in AAA tissue in relation to ILT thickness. Thick (A1) and thin (B1) segments of ILTs and aneurysm wall sections A (adjacent to A1) and B (adjacent to B1) from one aneurysm sac were taken from 35 patients undergoing elective repair. Factor levels were measured using enzyme-linked immunosorbent assay of protein extract. Tissue factor (TF) activities were significantly higher in thinner segments of AAA (B1 vs A1, P = .003; B vs A, P < .001; B vs A1, P < .001; B vs B1, P = .001). Significantly higher tissue plasminogen activator was found in thick thrombus-covered wall segments (A) than in B, A1, and B1 (P = .015, P < .001, and P < .001, respectively). Plasminogen concentrations were highest in ILT. Concentrations of α 2 -antiplasmin in thin ILT adjacent walls (B) were higher compared with wall (A) adjacent to thick ILT (P = .021) and thick ILT (A1; P < .001). Significant correlations between levels of different factors were mostly found in thick ILT (A1). However, no correlations were found at B sites, except for a correlation between plasmin and TF activities (r = 0.55; P = .004). These results suggest that higher TF activities are present in thinner AAA regions. These parameters and local fibrinolysis may be part of the processes leading to destruction of the aneurysm wall. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  9. Distance-from-the-wall scaling of turbulent motions in wall-bounded flows

    NASA Astrophysics Data System (ADS)

    Baidya, R.; Philip, J.; Hutchins, N.; Monty, J. P.; Marusic, I.

    2017-02-01

    An assessment of self-similarity in the inertial sublayer is presented by considering the wall-normal velocity, in addition to the streamwise velocity component. The novelty of the current work lies in the inclusion of the second velocity component, made possible by carefully conducted subminiature ×-probe experiments to minimise the errors in measuring the wall-normal velocity. We show that not all turbulent stress quantities approach the self-similar asymptotic state at an equal rate as the Reynolds number is increased, with the Reynolds shear stress approaching faster than the streamwise normal stress. These trends are explained by the contributions from attached eddies. Furthermore, the Reynolds shear stress cospectra, through its scaling with the distance from the wall, are used to assess the wall-normal limits where self-similarity applies within the wall-bounded flow. The results are found to be consistent with the recent prediction from the work of Wei et al. ["Properties of the mean momentum balance in turbulent boundary layer, pipe and channel flows," J. Fluid Mech. 522, 303-327 (2005)], Klewicki ["Reynolds number dependence, scaling, and dynamics of turbulent boundary layers," J. Fluids Eng. 132, 094001 (2010)], and others that the self-similar region starts and ends at z+˜O (√{δ+}) and O (δ+) , respectively. Below the self-similar region, empirical evidence suggests that eddies responsible for turbulent stresses begin to exhibit distance-from-the-wall scaling at a fixed z+ location; however, they are distorted by viscous forces, which remain a leading order contribution in the mean momentum balance in the region z+≲O (√{δ+}) , and thus result in a departure from self-similarity.

  10. Computed Tomography (CT) Imaging of Injuries from Blunt Abdominal Trauma: A Pictorial Essay.

    PubMed

    Hassan, Radhiana; Abd Aziz, Azian

    2010-04-01

    Blunt abdominal trauma can cause multiple internal injuries. However, these injuries are often difficult to accurately evaluate, particularly in the presence of more obvious external injuries. Computed tomography (CT) imaging is currently used to assess clinically stable patients with blunt abdominal trauma. CT can provide a rapid and accurate appraisal of the abdominal viscera, retroperitoneum and abdominal wall, as well as a limited assessment of the lower thoracic region and bony pelvis. This paper presents examples of various injuries in trauma patients depicted in abdominal CT images. We hope these images provide a resource for radiologists, surgeons and medical officers, as well as a learning tool for medical students.

  11. Comparison of spirometry and abdominal height as four-dimensional computed tomography metrics in lung

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lu Wei; Low, Daniel A.; Parikh, Parag J.

    2005-07-15

    An important consideration in four-dimensional CT scanning is the selection of a breathing metric for sorting the CT data and modeling internal motion. This study compared two noninvasive breathing metrics, spirometry and abdominal height, against internal air content, used as a surrogate for internal motion. Both metrics were shown to be accurate, but the spirometry showed a stronger and more reproducible relationship than the abdominal height in the lung. The abdominal height was known to be affected by sensor placement and patient positioning while the spirometer exhibited signal drift. By combining these two, a normalization of the drift-free metric tomore » tidal volume may be generated and the overall metric precision may be improved.« less

  12. Giant fibrosarcoma prostuberans of abodominal wall: management problems in resources-constrained country.

    PubMed

    Chukwuanukwu, T O G; Anyanwu, S N C

    2009-09-01

    Abdominal wall sarcomas represent less than 1% of adult malignancies. Dermatofibrosarcoma protuberans can grow to very large sizes and the recommended resection 2-3 cm from the macroscopic tumour margin can produce very large full thickness defects of the abdominal wall. Reconstruction of such defects can be quite challenging in resource constrained areas where patients present late with giant lesions. To highlight the presentation and management challenges faced by the surgical oncologist and reconstructive surgeon in a resource constrained country when faced with giant Dermatofibrosarcoma protuberans of the abdominal wall. Prospective study of patients with abdominal wall soft tissue sarcoma presenting to the authors. Cases of giant dermatofibrosarcoma protuberns who underwent surgery were analysed. Seven cases managed over an eight year period (January 2000 to December 2007). Age ranged from 27-70 yrs with slight female preponderance 1.5:1 F:M. Three presented with recurrent fungating masses. Only one could be reconstructed with prolene mesh. One recurrence was noted during the period under study. Poverty, ignorance and lack of necessary working tools are major challenges faced by the surgical oncologist and reconstructive surgeon in resource constrained areas and pose a major obstacle to the control of cancer in these areas.

  13. Development of real time abdominal compression force monitoring and visual biofeedback system

    NASA Astrophysics Data System (ADS)

    Kim, Tae-Ho; Kim, Siyong; Kim, Dong-Su; Kang, Seong-Hee; Cho, Min-Seok; Kim, Kyeong-Hyeon; Shin, Dong-Seok; Suh, Tae-Suk

    2018-03-01

    In this study, we developed and evaluated a system that could monitor abdominal compression force (ACF) in real time and provide a surrogating signal, even under abdominal compression. The system could also provide visual-biofeedback (VBF). The real-time ACF monitoring system developed consists of an abdominal compression device, an ACF monitoring unit and a control system including an in-house ACF management program. We anticipated that ACF variation information caused by respiratory abdominal motion could be used as a respiratory surrogate signal. Four volunteers participated in this test to obtain correlation coefficients between ACF variation and tidal volumes. A simulation study with another group of six volunteers was performed to evaluate the feasibility of the proposed system. In the simulation, we investigated the reproducibility of the compression setup and proposed a further enhanced shallow breathing (ESB) technique using VBF by intentionally reducing the amplitude of the breathing range under abdominal compression. The correlation coefficient between the ACF variation caused by the respiratory abdominal motion and the tidal volume signal for each volunteer was evaluated and R 2 values ranged from 0.79 to 0.84. The ACF variation was similar to a respiratory pattern and slight variations of ACF ranges were observed among sessions. About 73-77% average ACF control rate (i.e. compliance) over five trials was observed in all volunteer subjects except one (64%) when there was no VBF. The targeted ACF range was intentionally reduced to achieve ESB for VBF simulation. With VBF, in spite of the reduced target range, overall ACF control rate improved by about 20% in all volunteers except one (4%), demonstrating the effectiveness of VBF. The developed monitoring system could help reduce the inter-fraction ACF set up error and the intra fraction ACF variation. With the capability of providing a real time surrogating signal and VBF under compression, it could

  14. Current induced domain wall motion and tilting in Pt/Co/Ta structures with perpendicular magnetic anisotropy in the presence of the Dyzaloshinskii–Moriya interaction

    NASA Astrophysics Data System (ADS)

    Yun, Jijun; Li, Dong; Cui, Baoshan; Guo, Xiaobin; Wu, Kai; Zhang, Xu; Wang, Yupei; Mao, Jian; Zuo, Yalu; Xi, Li

    2018-04-01

    Current induced domain wall motion (CIDWM) was studied in Pt/Co/Ta structures with perpendicular magnetic anisotropy and the Dyzaloshinskii–Moriya interaction (DMI) by the spin-orbit torque (SOT). We measured the strength of DMI and SOT efficiency in Pt/Co/Ta with the variation of the thickness of Ta using a current induced hysteresis loop shift method. The results indicate that the DMI stabilizes a chiral Néel-type domain wall (DW), and the DW motion can be driven by the enhanced large SOT generated from Pt and Ta with opposite signs of spin Hall angle in Pt/Co/Ta stacks. The CIDWM velocity, which is 104 times larger than the field driven DW velocity, obeys a creep law, and reaches around tens of meters per second with current density of ~106 A cm‑2. We also found that the Joule heating accompanied with current also accelerates the DW motion. Meanwhile, a domain wall tilting was observed, which increases with current density increasing. These results can be explained by the spin Hall effect generated from both heavy metals Pt and Ta, inherent DMI, and the current accompanying Joule heating effect. Our results could provide some new designing prospects to move multiple DWs by SOT for achieving racetrack memories.

  15. Assessment of Tissue Perfusion Following Conventional Liposuction of Perforator-Based Abdominal Flaps

    PubMed Central

    Saçak, Bülent; Yalçın, Doğuş; Pilancı, Özgür; Tuncer, Fatma Betül; Çelebiler, Özhan

    2017-01-01

    Background The effect of liposuction on the perforators of the lower abdominal wall has been investigated in several studies. There are controversial results in the literature that have primarily demonstrated the number and patency of the perforators. The aim of this study was to determine the effect of liposuction on the perfusion of perforator-based abdominal flaps using a combined laser–Doppler spectrophotometer (O2C, Oxygen to See, LEA Medizintechnik). Methods Nine female patients undergoing classical abdominoplasty were included in the study. Perforators and the perfusion zones of the deep inferior epigastric artery flap were marked on the patient's abdominal wall. Flap perfusion was quantitatively assessed by measuring blood flow, velocity, capillary oxygen saturation, and relative amount of hemoglobin for each zone preoperatively, after tumescent solution infiltration, following elevation of the flap on a single perforator, and after deep and superficial liposuction, respectively. Results The measurements taken after elevation of the flap were not significantly different than measurements taken after the liposuction procedures. Conclusions The liposuction procedure does not significantly alter the perfusion of perforator-based abdominal flaps in the early period. The abdominal tissue discarded in a classic abdominoplasty operation can be raised as a perforator flap and has been demonstrated to be a unique model for clinical research. PMID:28352599

  16. Domain wall and interphase boundary motion in (1−x)Bi(Mg{sub 0.5}Ti{sub 0.5})O{sub 3}–xPbTiO{sub 3} near the morphotropic phase boundary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tutuncu, Goknur; Chen, Jun; Fan, Longlong

    Electric field-induced changes in the domain wall motion of (1−x)Bi(Mg{sub 0.5}Ti{sub 0.5})O{sub 3}–xPbTiO{sub 3} (BMT-xPT) near the morphotropic phase boundary (MPB) where x = 0.37 (BMT-37PT) and x = 0.38 (BMT-38PT), are studied by means of synchrotron x-ray diffraction. Through Rietveld analysis and profile fitting, a mixture of coexisting monoclinic (Cm) and tetragonal (P4mm) phases is identified at room temperature. Extrinsic contributions to the property coefficients are evident from electric-field-induced domain wall motion in both the tetragonal and monoclinic phases, as well as through the interphase boundary motion between the two phases. Domain wall motion in the tetragonal and monoclinic phases for BMT-37PT ismore » larger than that of BMT-38PT, possibly due to this composition's closer proximity to the MPB. Increased interphase boundary motion was also observed in BMT-37PT. Lattice strain, which is a function of both intrinsic piezoelectric strain and elastic interactions of the grains (the latter originating from domain wall and interphase boundary motion), is similar for the respective tetragonal and monoclinic phases.« less

  17. Evaluation of deformable image registration and a motion model in CT images with limited features.

    PubMed

    Liu, F; Hu, Y; Zhang, Q; Kincaid, R; Goodman, K A; Mageras, G S

    2012-05-07

    Deformable image registration (DIR) is increasingly used in radiotherapy applications and provides the basis for a previously described model of patient-specific respiratory motion. We examine the accuracy of a DIR algorithm and a motion model with respiration-correlated CT (RCCT) images of software phantom with known displacement fields, physical deformable abdominal phantom with implanted fiducials in the liver and small liver structures in patient images. The motion model is derived from a principal component analysis that relates volumetric deformations with the motion of the diaphragm or fiducials in the RCCT. Patient data analysis compares DIR with rigid registration as ground truth: the mean ± standard deviation 3D discrepancy of liver structure centroid positions is 2.0 ± 2.2 mm. DIR discrepancy in the software phantom is 3.8 ± 2.0 mm in lung and 3.7 ± 1.8 mm in abdomen; discrepancies near the chest wall are larger than indicated by image feature matching. Marker's 3D discrepancy in the physical phantom is 3.6 ± 2.8 mm. The results indicate that visible features in the images are important for guiding the DIR algorithm. Motion model accuracy is comparable to DIR, indicating that two principal components are sufficient to describe DIR-derived deformation in these datasets.

  18. Percutaneous debridement and washout of walled-off abdominal abscess and necrosis using flexible endoscopy: a large single-center experience.

    PubMed

    Mathers, Bradley; Moyer, Matthew; Mathew, Abraham; Dye, Charles; Levenick, John; Gusani, Niraj; Dougherty-Hamod, Brandy; McGarrity, Thomas

    2016-01-01

    Direct percutaneous endoscopic necrosectomy has been described as a minimally invasive intervention for the debridement of walled-off pancreatic necrosis (WOPN). In this retrospective cohort study, we aimed to confirm these findings in a US referral center and evaluate the clinical value of this modality in the treatment of pancreatic necrosis as well as other types of intra-abdominal fluid collections and necrosis. Twelve consecutive patients with WOPN or other abdominal abscess requiring debridement and washout underwent computed tomography (CT)-guided drainage catheter placement. Each patient then underwent direct percutaneous endoscopic necrosectomy and washout with repeat debridement performed until complete. Drains were then removed once output fell below 30 mL/day and imaging confirmed resolution. The primary endpoints were time to clinical resolution and sustained resolution at 1-year follow up.  Ten patients were treated for WOPN, one for necrotic hepatic abscesses, and one for omental necrosis. The median time to intervention was 85 days with an average of 2.3 necrosectomies performed. Complete removal of drains was accomplished in 11 patients (92 %). The median time to resolution was 57 days. No serious adverse events occurred; however, one patient developed pancreaticocutaneous fistulas. Ten patients completed 1-year surveillance of which none required drain replacement. No patients required surgery or repeat endoscopy. This series supports the premise that direct percutaneous endoscopic necrosectomy is a safe and effective intervention for intra-abdominal fluid collections and necrosis in appropriately selected patients. Our study demonstrates a high clinical success rate with minimal adverse events. This modality offers several potential advantages over surgical and transgastric approaches including use of improved accessibility, an excellent safety profile, and requirement for only deep or moderate sedation.

  19. Satisfaction and perceived quality of life results in patients operated on for primary hernia of the abdominal wall.

    PubMed

    de Miguel-Ibáñez, Ricardo; Nahban-Al Saied, Saif Adeen; Alonso-Vallejo, Javier; Escribano Sotos, Francisco

    2015-12-01

    Outpatient surgery is currently the standard procedure in 60-70% of the most prevalent surgical procedures. Minimally invasive models in health care have improved basic aspects such as postoperative pain and hospital stay, but there are few publications related to perceived quality shown by patients, such as the need for informal care at home or delay before surgery. The aim of the study was to determine the global satisfaction perceived by patients undergoing abdominal wall hernia repair. An ad hoc split questionnaire has been completed on satisfaction after a week and postoperative quality a month after intervention by 203 patients operated on for abdominal hernia in a year. Variables included postoperative pain, need for informal care, surgical delay, information supplied, professional management and overall satisfaction. A total of 48.28% of patients needed informal care at home. They were largely attended by women, wives or daughters, for a few days. In 45.81% they were discharged on the same day, and 53.2% in less than 72 h. Overall satisfaction in the program of day surgery and short hospital stay was 94.6%. The overall process of satisfaction was not related to age, sex or educational level of patients, while there was an inverse relationship between satisfaction and days of hospitalization and days of pain that required analgesia at home. Copyright © 2014 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. 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.

  1. The effects of nicotine administration on the pathophysiology of rat aortic wall.

    PubMed

    Kugo, H; Zaima, N; Tanaka, H; Urano, T; Unno, N; Moriyama, T

    2017-01-01

    Abdominal aortic aneurysm (AAA) is the progressive dilation of the abdominal aorta. Nicotine is reported to be associated with the development and rupture of AAA, but the pathological effects of nicotine on normal rat aorta have not been determined. We investigated pathological changes in the aortic wall of rats caused by the administration of nicotine. Nicotine administration weakened the vascular wall, increased gelatinolytic activity and promoted the destruction of elastin and collagen in the rat abdominal aorta. There were no differences in the areas positive for matrix metalloproteinase (MMP)-2 and MMP-9 between the control and nicotine treated groups. The areas positive for MMP-12 in the nicotine group were significantly greater than for the control group. Gelatinolytic activity in the aortic wall was increased significantly in the nicotine group. Our findings suggest that MMP-12 is sensitive to nicotine exposure in rats.

  2. [Tongue, trachea, abdominal wall, uterus, and penis allografts. More details on some other clinical applications of vascularized composite tissue allotransplantation].

    PubMed

    Petit, F

    2007-10-01

    The first hand and face allografts opened a new era in medicine history: a time when allotransplantation and reconstructive surgery coupled their principles. Their success and their development made composite tissue allotransplantation (CTA) a clinical reality for our speciality. Although still recent and limited, experience from this new surgical practice will widen with feedback from the first clinical cases and with experience gained from more clinical cases, more anatomical areas, more type of allografts, more surgical techniques, more immunosuppressive regimens. Tongue, trachea, abdominal wall, uterus, penis allotransplantations have been performed, contemporarily. Whatever the future and the benefits for the selected patients might have been, reports from these - un- and misknown - cases contribute to a better knowledge of CTA, its therapeutic potential, its limits, its challenges.

  3. Large-scale influences in near-wall turbulence.

    PubMed

    Hutchins, Nicholas; Marusic, Ivan

    2007-03-15

    Hot-wire data acquired in a high Reynolds number facility are used to illustrate the need for adequate scale separation when considering the coherent structure in wall-bounded turbulence. It is found that a large-scale motion in the log region becomes increasingly comparable in energy to the near-wall cycle as the Reynolds number increases. Through decomposition of fluctuating velocity signals, it is shown that this large-scale motion has a distinct modulating influence on the small-scale energy (akin to amplitude modulation). Reassessment of DNS data, in light of these results, shows similar trends, with the rate and intensity of production due to the near-wall cycle subject to a modulating influence from the largest-scale motions.

  4. Driving chiral domain walls in antiferromagnets using rotating magnetic fields

    NASA Astrophysics Data System (ADS)

    Pan, Keming; Xing, Lingdi; Yuan, H. Y.; Wang, Weiwei

    2018-05-01

    We show theoretically and numerically that an antiferromagnetic domain wall can be moved by a rotating magnetic field in the presence of Dzyaloshinskii-Moriya interaction (DMI). Two motion modes are found: rigid domain wall motion at low frequency (corresponding to the perfect frequency synchronization) and the oscillating motion at high frequency. In the full synchronized region, the steady velocity of the domain wall is universal, in the sense that it depends only on the frequency of the rotating field and the ratio between DMI strength and exchange constant. The domain wall velocity is independent of the Gilbert damping and the rotating field strength. Moreover, a rotating field in megahertz is sufficient to move the antiferromagnetic domain wall.

  5. Abdominal perforation after rupture of a diamond-studded wire: a case report.

    PubMed

    Schmelzle, Moritz; Matthaei, Hanno; Tustas, Roy Y; Schmitt, Marcus; Müller-Mattheis, Volker; Linhart, Wolfgang; Eisenberger, Claus F; Knoefel, Wolfram T; Esch, Jan Schulte Am

    2008-11-13

    There are numerous cases of abdominal injuries due to bullets. Abdominal injuries due to bullets are a diagnostic and therapeutic challenge. Here, an unusual case of an abdominal perforation caused by a metal projectile, lead to confusion in the interpretation of the preoperative computer tomography. We present an unusual case of a 32-year-old male worker who sustained a "shot" to the left upper abdominal quadrant, as a result of a work-related accident. The projectile derived from a special wire that tore during operation. One chain element happened to accelerate towards the patients belly and perforated the abdominal wall. Computer tomography located the radiopaque projectile to the cortex of the left kidney and showed a lesion of the tail of the pancreas. The presence of intraperitoneal free air suggested a gastrointestinal perforation. Immediate open exploration of the peritoneal cavity and the retroperitoneal space revealed perforating lesions of the anterior and posterior gastric wall, as well as the pancreatic tail. The projectile was finally retrieved in the upper pole of the left kidney. The patient had a good clinical course subsequent to surgery and was discharged in good general condition. This case represents a rare form of a retained bullet injury and corroborates the need of sufficient measures of worker-protection in area of diamond-studded wire cutting devices.

  6. Sci-Fri PM: Radiation Therapy, Planning, Imaging, and Special Techniques - 04: Assessment of intra-fraction motion during lung SABR VMAT using a custom abdominal compression device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hyde, Derek; Robinson, Mark; Araujo, Cynthia

    2016-08-15

    Purpose: Lung SABR patients are treated using Volumetrically Modulated Arc Therapy (VMAT), utilizing 2 arcs with Conebeam CT (CBCT) image-guidance prior to each arc. Intra-fraction imaging can prolong treatment time (up to 20%), and the aim of this study is to determine if it is necessary. Methods: We utilize an in-house abdominal compression device to minimize respiratory motion, 4DCT to define the ITV, a 5 mm PTV margin and a 2–3 mm PRV margin. We treated 23 patients with VMAT, fifteen were treated to 48 Gy in 4 fractions, while eight were treated with up to 60 Gy in 8more » fractions. Intrafraction motion was assessed by the translational errors recorded for the second CBCT. Results: There was no significant difference (t-test, p=0.93) in the intra-fraction motion between the patients treated with 4 and 8 fractions, or between the absolute translations in each direction (ANOVA, p=0.17). All 124 intra-fraction CBCT images were analysed and 95% remained localized within the 5 mm PTV margin The mean magnitude of the vector displacement was 1.8 mm. Conclusions: For patients localized with an abdominal compression device, the intrafraction CBCT image may not be necessary, if it is only the tumor coverage that is of concern, as the patients are typically well within the 5 mm PTV margin. On the other hand, if there is a structure with a smaller PRV margin, an intrafraction CBCT is recommended to ensure that the dose limit for the organ at risk is not exceeded.« less

  7. [Gallbladder contractility in children with functional abdominal pain or irritable bowel syndrome].

    PubMed

    Iwańczak, Franciszek; Siedlecka-Dawidko, Jolanta; Iwanczak, Barbara

    2013-07-01

    III Rome Criteria of functional gastrointestinal disorders in children, distinguished the disturbances with abdominal pain, to which irritable bowel syndrome, functional abdominal pains, functional dyspepsia and abdominal migraine were included. THE AIM OF THE STUDY was sonographic assessment of the gallbladder and its contractility in functional abdominal pain and irritable bowel syndrome in children. The study comprised 96 children aged 6 to 18 years, 59 girls and 37 boys. Depending on diagnosis, the children were divided into three groups. 38 children with functional abdominal pain constituted the first group, 26 children with irritable bowel syndrome were included to the second group, the third group consisted of 32 healthy children (control group). Diagnosis of functional abdominal pain and irritable bowel syndrome was made based on the III Rome Criteria. In irritable bowel syndrome both forms with diarrhea (13) and with constipation (13) were observed. Anatomy and contractility of the gallbladder were assessed by ultrasound examination. The presence of septum, wall thickness, thick bile, vesicle volume in fasting state and 30th and 60th minute after test meal were taken into consideration. Test meal comprised about 15% of caloric requirement of moderate metabolism. Children with bile stones and organic diseases were excluded from the study. Thickened vesicle wall and thick bile were present more frequently in children with irritable bowel syndrome and functional abdominal pain than in control group (p < 0.02). Fasting vesicle volume was significantly greater in children with functional abdominal pain than in irritable bowel syndrome and control group (p = 0.003, p = 0.05). Vesicle contractility after test meal was greatest in children with functional abdominal pain. Evaluation of diminished (smaller than 30%) and enlarged (greater then 80%) gallbladder contractility at 30th and 60th minute after test meal demonstrated disturbances of contractility in children

  8. Depinning of the transverse domain wall trapped at magnetic impurities patterned in planar nanowires: Control of the wall motion using low-intensity and short-duration current pulses

    NASA Astrophysics Data System (ADS)

    Paixão, E. L. M.; Toscano, D.; Gomes, J. C. S.; Monteiro, M. G.; Sato, F.; Leonel, S. A.; Coura, P. Z.

    2018-04-01

    Understanding and controlling of domain wall motion in magnetic nanowires is extremely important for the development and production of many spintronic devices. It is well known that notches are able to pin domain walls, but their pinning potential strength are too strong and it demands high-intensity current pulses to achieve wall depinning in magnetic nanowires. However, traps of pinning can be also originated from magnetic impurities, consisting of located variations of the nanowire's magnetic properties, such as exchange stiffness constant, saturation magnetization, anisotropy constant, damping parameter, and so on. In this work, we have performed micromagnetic simulations to investigate the depinning mechanism of a transverse domain wall (TDW) trapped at an artificial magnetic defect using spin-polarized current pulses. In order to create pinning traps, a simplified magnetic impurity model, only based on a local reduction of the exchange stiffness constant, have been considered. In order to provide a background for experimental studies, we have varied the parameter related to the pinning potential strength of the magnetic impurity. By adjusting the pinning potential of magnetic impurities and choosing simultaneously a suitable current pulse, we have found that it is possible to obtain domain wall depinning by applying low-intensity and short-duration current pulses. Furthermore, it was considered a planar magnetic nanowire containing a linear distribution of equally-spaced magnetic impurities and we have demonstrated the position control of a single TDW by applying sequential current pulses; that means the wall movement from an impurity to another.

  9. Effect of Emodin on Preventing Postoperative Intra-Abdominal Adhesion Formation.

    PubMed

    Wei, Guangbing; Wu, Yunhua; Gao, Qi; Zhou, Cancan; Wang, Kai; Shen, Cong; Wang, Guanghui; Wang, Kang; Sun, Xuejun; Li, Xuqi

    2017-01-01

    Postoperative intra-abdominal adhesions are a major complication after abdominal surgery. Although various methods have been used to prevent and treat adhesions, the effects have not been satisfactory. Emodin, a naturally occurring anthraquinone derivative and an active ingredient in traditional Chinese herbs, exhibits a variety of pharmacological effects. In our study, we demonstrated the effect of emodin treatment on preventing postoperative adhesion formation. A total of 48 rats were divided into six groups. Abdominal adhesions were created by abrasion of the cecum and its opposite abdominal wall. In the experimental groups, the rats were administered daily oral doses of emodin. On the seventh day after operation, the rats were euthanized, and blood and pathological specimens were collected. Abdominal adhesion formation was evaluated by necropsy, pathology, immunohistochemistry, Western blot, and enzyme-linked immunosorbent assay analyses. Abdominal adhesions were markedly reduced by emodin treatment. Compared with the control group, collagen deposition was reduced and the peritoneal mesothelial completeness rate was higher in the emodin-treated groups. Emodin had anti-inflammatory effects, reduced oxidative stress, and promoted the movement of the intestinal tract ( P < 0.05). Emodin significantly reduced intra-abdominal adhesion formation in a rat model.

  10. Abdominal wall integrity after open abdomen: long-term results of vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM).

    PubMed

    Willms, A; Schaaf, S; Schwab, R; Richardsen, I; Bieler, D; Wagner, B; Güsgen, C

    2016-12-01

    The open abdomen has become a standard technique in the management of critically ill patients undergoing surgery for severe intra-abdominal conditions. Negative pressure and mesh-mediated fascial traction are commonly used and achieve low fistula rates and high fascial closure rates. In this study, long-term results of a standardised treatment approach are presented. Fifty-five patients who underwent OA management for different indications at our institution from 2006 to 2013 were enrolled. All patients were treated under a standardised algorithm that uses a combination of vacuum-assisted wound closure and mesh-mediated fascial traction. Structured follow-up assessments were offered to patients and included a medical history, a clinical examination and abdominal ultrasonography. The data obtained were statistically analysed. The fascial closure rate was 74 % in an intention-to-treat analysis and 89 % in a per-protocol analysis. The fistula rate was 1.8 %. Thirty-four patients attended follow-up. The median follow-up was 46 months (range 12-88 months). Incisional hernias developed in 35 %. Patients with hernias needed more operative procedures (10.3 vs 3.4, p = 0.03) than patients without hernia formation. A Patient Observer Scar Assessment Scale (POSAS) of 31.1 was calculated. Patients with symptomatic hernias (NAS of 2-10) had a significantly lower mean POSAS score (p = 0.04). Vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) seem to result in low complication rates and high fascial closure rates. Abdominal wall reconstruction, which is a challenging and complex procedure and causes considerable patient discomfort, can thus be avoided in the majority of cases. Available results are based on studies involving only a small number of cases. Multi-centre studies and registry-based data are therefore needed to validate these findings.

  11. Low-Grade Myxofibrosarcoma of the Rectus Abdominus Muscle Infiltrating into Abdominal Cavity: A Case Report.

    PubMed

    Nomura, Tadashi; Sakakibara, Shunsuke; Moriwaki, Aya; Kawamoto, Teruya; Suzuki, Satoshi; Ishimura, Takeshi; Hashikawa, Kazunobu; Terashi, Hiroto

    2017-01-01

    Objective: Myxofibrosarcoma (MFS) is a relatively rare tumor that is histologically characterized by myxoid stroma and spindle cell proliferation. This tumor most commonly arises as a slow growing, enlarging painless mass in the extremities of elderly patients. Methods: We report a case of a primary, low-grade MFS in the rectus abdominis muscle infiltrating the abdominal cavity of a 75-year-old man. Results: The patient underwent a wide excision of the right abdominal wall mass with a 3-cm surgical margin from the scar due to a biopsy. The tumor infiltrated the urinary bladder, peritoneum, and external iliac vessels. Twenty-six months after the initial operation, he had recurrences in his abdominal wall, urinary bladder, and right iliac vessels. Conclusions: To our knowledge, primary MFS of the muscle in the abdomen has not been documented previously. Although this case was histopathologically classified as a low-grade tumor, it infiltrated the abdominal cavity. The tumor is suspected to have penetrated the abdominal cavity below the linea arcuata, which lacks the posterior sheath of the rectus abdominis muscle; from there, it could easily spread without being blocked by any biological barriers.

  12. Assessment of abdominal muscle function using the Biodex System-4. Validity and reliability in healthy volunteers and patients with giant ventral hernia.

    PubMed

    Gunnarsson, U; Johansson, M; Strigård, K

    2011-08-01

    The decrease in recurrence rates in ventral hernia surgery have led to a redirection of focus towards other important patient-related endpoints. One such endpoint is abdominal wall function. The aim of the present study was to evaluate the reliability and external validity of abdominal wall strength measurement using the Biodex System-4 with a back abdomen unit. Ten healthy volunteers and ten patients with ventral hernias exceeding 10 cm were recruited. Test-retest reliability, both with and without girdle, was evaluated by comparison of measurements at two test occasions 1 week apart. Reliability was calculated by the interclass correlation coefficients (ICC) method. Validity was evaluated by correlation with the well-established International Physical Activity Questionnaire (IPAQ) and a self-assessment of abdominal wall strength. One person in the healthy group was excluded after the first test due to neck problems following minor trauma. The reliability was excellent (>0.75), with ICC values between 0.92 and 0.97 for the different modalities tested. No differences were seen between testing with and without a girdle. Validity was also excellent both when calculated as correlation to self-assessment of abdominal wall strength, and to IPAQ, giving Kendall tau values of 0.51 and 0.47, respectively, and corresponding P values of 0.002 and 0.004. Measurement of abdominal muscle function using the Biodex System-4 is a reliable and valid method to assess this important patient-related endpoint. Further investigations will be made to explore the potential of this technique in the evaluation of the results of ventral hernia surgery, and to compare muscle function after different abdominal wall reconstruction techniques.

  13. [Abdomen specific bioelectrical impedance analysis (BIA) methods for evaluation of abdominal fat distribution].

    PubMed

    Ida, Midori; Hirata, Masakazu; Hosoda, Kiminori; Nakao, Kazuwa

    2013-02-01

    Two novel bioelectrical impedance analysis (BIA) methods have been developed recently for evaluation of intra-abdominal fat accumulation. Both methods use electrodes that are placed on abdominal wall and allow evaluation of intra-abdominal fat area (IAFA) easily without radiation exposure. Of these, "abdominal BIA" method measures impedance distribution along abdominal anterior-posterior axis, and IAFA by BIA method(BIA-IAFA) is calculated from waist circumference and the voltage occurring at the flank. Dual BIA method measures impedance of trunk and body surface at the abdominal level and calculates BIA-IAFA from transverse and antero-posterior diameters of the abdomen and the impedance of trunk and abdominal surface. BIA-IAFA by these two BIA methods correlated well with IAFA measured by abdominal CT (CT-IAFA) with correlatipn coefficient of 0.88 (n = 91, p < 0.0001) for the former, and 0.861 (n = 469, p < 0.01) for the latter. These new BIA methods are useful for evaluating abdominal adiposity in clinical study and routine clinical practice of metabolic syndrome and obesity.

  14. 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.

  15. Motion of a Janus particle very near a wall

    NASA Astrophysics Data System (ADS)

    Rashidi, Aidin; Wirth, Christopher L.

    2017-12-01

    This article describes the simulated Brownian motion of a sphere comprising hemispheres of unequal zeta potential (i.e., "Janus" particle) very near a wall. The simulation tool was developed and used to assist in the methodology development for applying Total Internal Reflection Microscopy (TIRM) to anisotropic particles. Simulations of the trajectory of a Janus sphere with cap density matching that of the base particle very near a boundary were used to construct 3D potential energy landscapes that were subsequently used to infer particle and solution properties, as would be done in a TIRM measurement. Results showed that the potential energy landscape of a Janus sphere has a transition region at the location of the boundary between the two Janus halves, which depended on the relative zeta potential magnitude. The potential energy landscape was fit to accurately obtain the zeta potential of each hemisphere, particle size, minimum potential energy position and electrolyte concentration, or Debye length. We also determined the appropriate orientation bin size and regimes over which the potential energy landscape should be fit to obtain system properties. Our simulations showed that an experiment may require more than 106 observations to obtain a suitable potential energy landscape as a consequence of the multivariable nature of observations for an anisotropic particle. These results illustrate important considerations for conducting TIRM for anisotropic particles.

  16. A Rare Case of Giant Basal Cell Carcinoma of the Abdominal Wall: Excision and Immediate Reconstruction with a Pedicled Deep Inferior Epigastric Artery Perforator (DIEP) Flap

    PubMed Central

    Di Lorenzo, Sara; Zabbia, Giovanni; Corradino, Bartolo; Tripoli, Massimiliano; Pirrello, Roberto; Cordova, Adriana

    2017-01-01

    Patient: Female, 82 Final Diagnosis: Giant basal cell carcinoma Symptoms: Anemia Medication: — Clinical Procedure: — Specialty: Plastic Surgery Objective: Rare disease Background: Basal cell carcinoma (BCC) greater than 5 cm in diameter is called giant basal cell carcinoma (GBCC), or super giant basal cell carcinoma if it has a diameter larger than 20 cm. Giant BCC only accounts for 0.5% of BCCs and super giant BCC is exceedingly rare. On account of their rarity, there are no established guidelines for GBCC treatment. Case Report: We describe a peculiar case of an 82-year-old woman with a GBCC carcinoma of the lower abdominal wall. The tumor was surgically removed with ipsilateral inguinal lymph nodes and the abdominal wall was reconstructed immediately with a pedicled deep inferior epigastric artery perforator (DIEP) flap. Conclusions: Treatment of giant basal cell carcinoma is often difficult, especially in elderly patients with poor general health and multiple pathologies. The pedicled DIEP flap is rotated to cover the loss of substance without tension, and it is easy to harvest and transfer. This flap allowed a good result without local or systemic complication. We present this report as a reminder of the occasional occurrence of extremely aggressive BCCs. We believe that, especially for rare tumors like these, it is very useful for the entire scientific community to publish these cases and the therapeutic strategies used to treat them. PMID:29199268

  17. Preincisional intraparietal Augmentin in abdominal operations.

    PubMed Central

    Pollock, A. V.; Evans, M.; Smith, G. M.

    1989-01-01

    A total of 624 consecutive eligible patients undergoing abdominal operations received a single preoperative dose of amoxycillin/clavulanic acid (1.2 g Augmentin) for the prophylaxis of surgical wound infection. They were randomised to have the antibiotic injected intravenously at induction of anaesthesia (n = 328) or infiltrated subcutaneously along the line of the proposed incision (n = 296). The incidence of wound infections was considerably lower in the group given the antibiotic into the abdominal wall (8.4% compared with 15.9%--chi 2 = 7.90, P = 0.005). No significant differences were found in the incidence of other major or minor infective or non-infective postoperative complications between the groups. It is concluded that preincisional intraparietal injection is more effective than intravenous injection of Augmentin for the prophylaxis of surgical wound infection. PMID:2523210

  18. Noninvasive detection of coronary artery wall thickening with age in healthy subjects using high resolution MRI with beat-to-beat respiratory motion correction.

    PubMed

    Scott, Andrew D; Keegan, Jennifer; Mohiaddin, Raad H; Firmin, David N

    2011-10-01

    To demonstrate coronary artery wall thickening with age in a small healthy cohort using a highly efficient, reliable, and reproducible high-resolution MR technique. A 3D cross-sectional MR vessel wall images (0.7 × 0.7 × 3 mm resolution) with retrospective beat-to-beat respiratory motion correction (B2B-RMC) were obtained in the proximal right coronary artery of 21 healthy subjects (age, 22-62 years) with no known cardiovascular disease. Lumen and outer wall (lumen + vessel wall) areas were measured in one central slice from each subject and average wall thickness and wall area/outer wall area ratio (W/OW) calculated. Imaging was successful in 18 (86%) subjects with average respiratory efficiency 99.3 ± 1.7%. Coronary vessel wall thickness and W/OW significantly correlate with subject age, increasing by 0.088 mm and 0.031 per decade respectively (R = 0.53, P = 0.024 and R = 0.48, P = 0.046). No relationship was found between lumen area and vessel wall thickness (P = NS), but outer wall area increased significantly with vessel wall thickness at 19 mm(2) per mm (P = 0.046). This is consistent with outward vessel wall remodeling. Despite the small size of our healthy cohort, using high-resolution MR imaging and B2B-RMC, we have demonstrated increasing coronary vessel wall thickness and W/OW with age. The results obtained are consistent with outward vessel wall remodeling. Copyright © 2011 Wiley-Liss, Inc.

  19. Effect of Emodin on Preventing Postoperative Intra-Abdominal Adhesion Formation

    PubMed Central

    Wei, Guangbing; Zhou, Cancan; Wang, Guanghui; Wang, Kang

    2017-01-01

    Background Postoperative intra-abdominal adhesions are a major complication after abdominal surgery. Although various methods have been used to prevent and treat adhesions, the effects have not been satisfactory. Emodin, a naturally occurring anthraquinone derivative and an active ingredient in traditional Chinese herbs, exhibits a variety of pharmacological effects. In our study, we demonstrated the effect of emodin treatment on preventing postoperative adhesion formation. Materials and Methods A total of 48 rats were divided into six groups. Abdominal adhesions were created by abrasion of the cecum and its opposite abdominal wall. In the experimental groups, the rats were administered daily oral doses of emodin. On the seventh day after operation, the rats were euthanized, and blood and pathological specimens were collected. Abdominal adhesion formation was evaluated by necropsy, pathology, immunohistochemistry, Western blot, and enzyme-linked immunosorbent assay analyses. Results Abdominal adhesions were markedly reduced by emodin treatment. Compared with the control group, collagen deposition was reduced and the peritoneal mesothelial completeness rate was higher in the emodin-treated groups. Emodin had anti-inflammatory effects, reduced oxidative stress, and promoted the movement of the intestinal tract (P < 0.05). Conclusion Emodin significantly reduced intra-abdominal adhesion formation in a rat model. PMID:28831292

  20. Novel Assessment of Renal Motion in Children as Measured via Four-Dimensional Computed Tomography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pai Panandiker, Atmaram S., E-mail: atmaram.pai-panandiker@stjude.org; Sharma, Shelly; Naik, Mihir H.

    Objectives: Abdominal intensity-modulated radiation therapy and proton therapy require quantification of target and organ motion to optimize localization and treatment. Although addressed in adults, there is no available literature on this issue in pediatric patients. We assessed physiologic renal motion in pediatric patients. Methods and Materials: Twenty free-breathing pediatric patients at a median age of 8 years (range, 2-18 years) with intra-abdominal tumors underwent computed tomography simulation and four-dimensional computed tomography acquisition (slice thickness, 3 mm). Kidneys and diaphragms were contoured during eight phases of respiration to estimate center-of-mass motion. We quantified center of kidney mass mobility vectors in threemore » dimensions: anteroposterior (AP), mediolateral (ML), and superoinferior (SI). Results: Kidney motion decreases linearly with decreasing age and height. The 95% confidence interval for the averaged minima and maxima of renal motion in children younger than 9 years was 5-9 mm in the ML direction, 4-11 mm in the AP direction, and 12-25 mm in the SI dimension for both kidneys. In children older than 9 years, the same confidence interval reveals a widening range of motion that was 5-16 mm in the ML direction, 6-17 mm in the AP direction, and 21-52 mm in the SI direction. Although not statistically significant, renal motion correlated with diaphragm motion in older patients. The correlation between diaphragm motion and body mass index was borderline (r = 0.52, p = 0.0816) in younger patients. Conclusions: Renal motion is age and height dependent. Measuring diaphragmatic motion alone does not reliably quantify pediatric renal motion. Renal motion in young children ranges from 5 to 25 mm in orientation-specific directions. The vectors of motion range from 5 to 52 mm in older children. These preliminary data represent novel analyses of pediatric intra-abdominal organ motion.« less

  1. Cone-Beam Computed Tomography Internal Motion Tracking Should Be Used to Validate 4-Dimensional Computed Tomography for Abdominal Radiation Therapy Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rankine, Leith; Wan, Hanlin; Parikh, Parag

    Purpose: To demonstrate that fiducial tracking during pretreatment Cone-Beam CT (CBCT) can accurately measure tumor motion and that this method should be used to validate 4-dimensional CT (4DCT) margins before each treatment fraction. Methods and Materials: For 31 patients with abdominal tumors and implanted fiducial markers, tumor motion was measured daily with CBCT and fluoroscopy for 202 treatment fractions. Fiducial tracking and maximum-likelihood algorithms extracted 3-dimensional fiducial trajectories from CBCT projections. The daily internal margin (IM) (ie, range of fiducial motion) was calculated for CBCT and fluoroscopy as the 5th-95th percentiles of displacement in each cardinal direction. The planning IMmore » from simulation 4DCT (IM{sub 4DCT}) was considered adequate when within ±1.2 mm (anterior–posterior, left–right) and ±3 mm (superior–inferior) of the daily measured IM. We validated CBCT fiducial tracking as an accurate predictive measure of intrafraction motion by comparing the daily measured IM{sub CBCT} with the daily IM measured by pretreatment fluoroscopy (IM{sub pre-fluoro}); these were compared with pre- and posttreatment fluoroscopy (IM{sub fluoro}) to identify those patients who could benefit from imaging during treatment. Results: Four-dimensional CT could not accurately predict intrafractional tumor motion for ≥80% of fractions in 94% (IM{sub CBCT}), 97% (IM{sub pre-fluoro}), and 100% (IM{sub fluoro}) of patients. The IM{sub CBCT} was significantly closer to IM{sub pre-fluoro} than IM{sub 4DCT} (P<.01). For patients with median treatment time t < 7.5 minutes, IM{sub CBCT} was in agreement with IM{sub fluoro} for 93% of fractions (superior–inferior), compared with 63% for the t > 7.5 minutes group, demonstrating the need for patient-specific intratreatment imaging. Conclusions: Tumor motion determined from 4DCT simulation does not accurately predict the daily motion observed on CBCT or fluoroscopy. Cone-beam CT

  2. Swimming trajectories of a three-sphere microswimmer near a wall

    NASA Astrophysics Data System (ADS)

    Daddi-Moussa-Ider, Abdallah; Lisicki, Maciej; Hoell, Christian; Löwen, Hartmut

    2018-04-01

    The hydrodynamic flow field generated by self-propelled active particles and swimming microorganisms is strongly altered by the presence of nearby boundaries in a viscous flow. Using a simple model three-linked sphere swimmer, we show that the swimming trajectories near a no-slip wall reveal various scenarios of motion depending on the initial orientation and the distance separating the swimmer from the wall. We find that the swimmer can either be trapped by the wall, completely escape, or perform an oscillatory gliding motion at a constant mean height above the wall. Using a far-field approximation, we find that, at leading order, the wall-induced correction has a source-dipolar or quadrupolar flow structure where the translational and angular velocities of the swimmer decay as inverse third and fourth powers with distance from the wall, respectively. The resulting equations of motion for the trajectories and the relevant order parameters fully characterize the transition between the states and allow for an accurate description of the swimming behavior near a wall. We demonstrate that the transition between the trapping and oscillatory gliding states is first order discontinuous, whereas the transition between the trapping and escaping states is continuous, characterized by non-trivial scaling exponents of the order parameters. In order to model the circular motion of flagellated bacteria near solid interfaces, we further assume that the spheres can undergo rotational motion around the swimming axis. We show that the general three-dimensional motion can be mapped onto a quasi-two-dimensional representational model by an appropriate redefinition of the order parameters governing the transition between the swimming states.

  3. The Effect of Ethanol Extract of Rose (Rosa damascena) on Intra-abdominal Adhesions After Laparotomy in Rats.

    PubMed

    Karimi, Mehrdad; Yazdan Asadi, Sayyed; Parsaei, Pouya; Rafieian-Kopaei, Mahmoud; Ghaheri, Hafez; Ezzati, Sareh

    2016-05-01

    Abdominal adhesions are pathological connections in peritoneal surfaces that are created after abdominal surgery. The aim of this study was to evaluate the inhibitory effect of Rosa damascena extract on adhesions, considering the antioxidant properties of rose. Thirty healthy rats were divided into 3 groups: rats treated by 1% (A) and 5% (B) of R. damascena extract and the con- trol group (C). After administering anesthesia, the abdominal wall was opened and 3 shallow incisions (2 cm) were made on the right wall, and a 2 × 2 piece of peritoneal surface was removed on the left side of the abdominal wall. Then 3 mL of 1% (A) and 5% (B) R. damascena extract was administered into the abdominal cavity. The control group (C) received 3 mL of distilled water. The abdominal cavity was sutured, and a second laparotomy was carried out 14 days later to the created adhesions according to the Canbaz scale, and a histopathologic examination was also performed. All data was analyzed by SPSS volume 16 (Chicago, IL); P less than 0.05 was considered statistically significant. The amount of adhesion in group A was significantly lower than that of group C, 1.4 ± 1.265 versus 3 ± 0.816, (P = 0.007). The histological investigation also showed significant differences in the se- verity of fibrosis (P = 0.029) and inflammation (P = 0.009) between groups A and C; all rats in group B (5%) were found dead. This study indicated the use of R. damascena at a 1% level resulted in a remarkable decrease of intra-abdominal adhesions after laparotomy in rats. Further studies are necessary on this extract and its derivatives for treatment of such diseases in the human model.

  4. Cost identification of abdominal aortic aneurysm imaging by using time and motion analyses.

    PubMed

    Rubin, G D; Armerding, M D; Dake, M D; Napel, S

    2000-04-01

    To compare the costs of performing helical computed tomographic (CT) angiography with three-dimensional rendering versus intraarterial digital subtraction angiography (DSA) for preoperative imaging of abdominal aortic aneurysms (AAAs). A single observer determined the variable direct costs of performing nine intraarterial DSA and 10 CT angiographic examinations in age- and general health-matched patients with AAA by using time and motion analyses. All personnel directly involved in the cases were tracked, and the involvement times were recorded to the nearest minute. All material items used during the procedures were recorded. The cost of labor was determined from personnel reimbursement data, and the cost of materials, from vendor pricing. The variable direct costs of laboratory tests and using the ambulatory treatment unit for postprocedural monitoring, as well as all fixed direct costs, were assessed from hospital accounting records. The total costs were determined for each procedure and compared by using the Student t test and calculating the CIs. The mean total direct cost of intraarterial DSA (+/- SD) was $1,052 +/- 71, and that of CT angiography was $300 +/- 30, which are significantly different (P < 4.1 x 10(-11)). With 95% confidence, intraarterial DSA cost 3.2-3.7 times more than CT angiography for the assessment of AAA. Assuming equal diagnostic utility and procedure-related morbidity, institutions may have substantial cost savings whenever CT angiography can replace intraarterial DSA for imaging AAAs.

  5. Characterization of the Test Section Walls at the 14- by 22-Foot Subsonic Tunnel

    NASA Technical Reports Server (NTRS)

    Lunsford, Charles B.; Graves, Sharon S.

    2003-01-01

    The test section walls of the NASA Langley Research Center 14- by 22-Foot Subsonic Tunnel are known to move under thermal and pressure loads. Videogrammetry was used to measure wall motion during the summer of 2002. In addition, a laser distancemeter was used to measure the relative distance between the test section walls at a single point. Distancemeter and videogrammetry results were consistent. Data were analyzed as a function of temperature and pressure to determine their effects on wall motion. Data were collected between 50 and 100 F, 0 and 0.315 Mach, and dynamic pressures of 0 and 120 psf. The overall motion of each wall was found to be less than 0.25 in. and less than facility personnel anticipated. The results show how motion depends on the temperature and pressure inside the test section as well is the position of the boundary layer vane. The repeatability of the measurements was +/-0.06 in. This report describes the methods used to record the motion of the test section walls and the results of the data analysis. Future facility plans include the development of a suitable wall restraint system and the determination of the effects of the wall motion on tunnel calibration.

  6. 3-D simulation of hanging wall effect at dam site

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Xu, Y.

    2017-12-01

    Hanging wall effect is one of the near fault effects. This paper focuses on the difference of the ground motions on the hanging wall side between the footwall side of the fault at dam site considering the key factors, such as actual topography, the rupture process. For this purpose, 3-D ground motions are numerically simulated by the spectrum element method (SEM), which takes into account the physical mechanism of generation and propagation of seismic waves. With the SEM model of 548 million DOFs, excitation and propagation of seismic waves are simulated to compare the difference between the ground motion on the hanging wall side and that on the footwall side. Take Dagangshan region located in China as an example, several seismogenic finite faults with different dip angle are simulated to investigate the hanging wall effect. Furthermore, by comparing the ground motions of the receiving points, the influence of several factors on hanging wall effect is investigated, such as the dip of the fault and the fault type (strike slip fault or dip-slip fault). The peak acceleration on the hanging wall side is obviously larger than those on the footwall side, which numerically evidences the hanging wall effect. Besides, the simulation shows that only when the dip is less than 70° does the hanging wall effect deserve attention.

  7. The Influence of a Pfannenstiel Scar on Venous Anatomy of the Lower Abdominal Wall and Implications for Deep Inferior Epigastric Artery Perforator Flap Breast Reconstruction.

    PubMed

    Kim, So Young; Lee, Kyeong-Tae; Mun, Goo-Hyun

    2017-03-01

    A Pfannenstiel incision involves the obstruction of superficial venous pathways and functional diversion of flow through alternative pathways and adjacent vessels. This study investigated the effect of a prior Pfannenstiel incision on venous anatomy of the lower abdominal wall; specifically, the superficial inferior epigastric vein (SIEV), using computed tomographic angiography. A case-control study was performed of 50 patients with Pfannenstiel scars and 50 age-matched, body mass index-matched control patients without Pfannenstiel scars. The authors compared the number of direct/indirect and total communications between the SIEV and deep inferior epigastric artery perforator (DIEP) venae comitantes, midline crossover, and other SIEV-related anatomical changes by using computed tomographic angiography. Flap-related clinical outcomes and donor-site-related complications were also assessed. The median number of direct and total communications between the SIEV and DIEP venae comitantes in the study group was greater than in the control group. The percentage of SIEVs having more than two branching patterns per hemiabdomen was significantly higher in the study group than in the control group. The study group also showed a significantly lower rate of fat necrosis compared with the control group (p = 0.03). The rate of donor-site seroma was significantly higher in the study group. This study suggests that the presence of a Pfannenstiel scar may promote the development of direct and total communications between the SIEV and DIEP venae comitantes and branching within the SIEV in the lower abdominal wall, which may facilitate venous drainage of adipose tissue in DIEP flap breast reconstruction. Risk, II.

  8. Non-rigid Motion Correction in 3D Using Autofocusing with Localized Linear Translations

    PubMed Central

    Cheng, Joseph Y.; Alley, Marcus T.; Cunningham, Charles H.; Vasanawala, Shreyas S.; Pauly, John M.; Lustig, Michael

    2012-01-01

    MR scans are sensitive to motion effects due to the scan duration. To properly suppress artifacts from non-rigid body motion, complex models with elements such as translation, rotation, shear, and scaling have been incorporated into the reconstruction pipeline. However, these techniques are computationally intensive and difficult to implement for online reconstruction. On a sufficiently small spatial scale, the different types of motion can be well-approximated as simple linear translations. This formulation allows for a practical autofocusing algorithm that locally minimizes a given motion metric – more specifically, the proposed localized gradient-entropy metric. To reduce the vast search space for an optimal solution, possible motion paths are limited to the motion measured from multi-channel navigator data. The novel navigation strategy is based on the so-called “Butterfly” navigators which are modifications to the spin-warp sequence that provide intrinsic translational motion information with negligible overhead. With a 32-channel abdominal coil, sufficient number of motion measurements were found to approximate possible linear motion paths for every image voxel. The correction scheme was applied to free-breathing abdominal patient studies. In these scans, a reduction in artifacts from complex, non-rigid motion was observed. PMID:22307933

  9. Prevention of intra-abdominal adhesion by bi-layer electrospun membrane.

    PubMed

    Jiang, Shichao; Wang, Wei; Yan, Hede; Fan, Cunyi

    2013-06-04

    The aim of this study was to compare the anti-adhesion efficacy of a bi-layer electrospun fibrous membrane consisting of hyaluronic acid-loaded poly(ε-caprolactone) (PCL) fibrous membrane as the inner layer and PCL fibrous membrane as the outer layer with a single-layer PCL electrospun fibrous membrane in a rat cecum abrasion model. The rat model utilized a cecal abrasion and abdominal wall insult surgical protocol. The bi-layer and PCL membranes were applied between the cecum and the abdominal wall, respectively. Control animals did not receive any treatment. After postoperative day 14, a visual semiquantitative grading scale was used to grade the extent of adhesion. Histological analysis was performed to reveal the features of adhesion tissues. Bi-layer membrane treated animals showed significantly lower adhesion scores than control animals (p < 0.05) and a lower adhesion score compared with the PCL membrane. Histological analysis of the bi-layer membrane treated rat rarely demonstrated tissue adhesion while that of the PCL membrane treated rat and control rat showed loose and dense adhesion tissues, respectively. Bi-layer membrane can efficiently prevent adhesion formation in abdominal cavity and showed a significantly decreased adhesion tissue formation compared with the control.

  10. An MRI-compatible platform for one-dimensional motion management studies in MRI.

    PubMed

    Nofiele, Joris; Yuan, Qing; Kazem, Mohammad; Tatebe, Ken; Torres, Quinn; Sawant, Amit; Pedrosa, Ivan; Chopra, Rajiv

    2016-08-01

    Abdominal MRI remains challenging because of respiratory motion. Motion compensation strategies are difficult to compare clinically because of the variability across human subjects. The goal of this study was to evaluate a programmable system for one-dimensional motion management MRI research. A system comprised of a programmable motorized linear stage and computer was assembled and tested in the MRI environment. Tests of the mutual interference between the platform and a whole-body MRI were performed. Organ trajectories generated from a high-temporal resolution scan of a healthy volunteer were used in phantom tests to evaluate the effects of motion on image quality and quantitative MRI measurements. No interference between the motion platform and the MRI was observed, and reliable motion could be produced across a wide range of imaging conditions. Motion-related artifacts commensurate with motion amplitude, frequency, and waveform were observed. T2 measurement of a kidney lesion in an abdominal phantom showed that its value decreased by 67% with physiologic motion, but could be partially recovered with navigator-based motion-compensation. The motion platform can produce reliable linear motion within a whole-body MRI. The system can serve as a foundation for a research platform to investigate and develop motion management approaches for MRI. Magn Reson Med 76:702-712, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  11. Dominance of free wall radial motion in global right ventricular function of heart transplant recipients.

    PubMed

    Lakatos, Bálint Károly; Tokodi, Márton; Assabiny, Alexandra; Tősér, Zoltán; Kosztin, Annamária; Doronina, Alexandra; Rácz, Kristóf; Koritsánszky, Kinga Bianka; Berzsenyi, Viktor; Németh, Endre; Sax, Balázs; Kovács, Attila; Merkely, Béla

    2018-03-01

    Assessment of right ventricular (RV) function using conventional echocardiography might be inadequate as the radial motion of the RV free wall is often neglected. Our aim was to quantify the longitudinal and the radial components of RV function using three-dimensional (3D) echocardiography in heart transplant (HTX) recipients. Fifty-one HTX patients in stable cardiovascular condition without history of relevant rejection episode or chronic allograft vasculopathy and 30 healthy volunteers were enrolled. RV end-diastolic (EDV) volume and total ejection fraction (TEF) were measured by 3D echocardiography. Furthermore, we quantified longitudinal (LEF) and radial ejection fraction (REF) by decomposing the motion of the RV using the ReVISION method. RV EDV did not differ between groups (HTX vs control; 96 ± 27 vs 97 ± 2 mL). In HTX patients, TEF was lower, however, tricuspid annular plane systolic excursion (TAPSE) decreased to a greater extent (TEF: 47 ± 7 vs 54 ± 4% [-13%], TAPSE: 11 ± 5 vs 21 ± 4 mm [-48%], P < .0001). In HTX patients, REF/TEF ratio was significantly higher compared to LEF/TEF (REF/TEF vs LEF/TEF: 0.58 ± 0.10 vs 0.27 ± 0.08, P < .0001), while in controls the REF/TEF and LEF/TEF ratio was similar (0.45 ± 0.07 vs 0.47 ± 0.07). Current results confirm the superiority of radial motion in determining RV function in HTX patients. Parameters incorporating the radial motion are recommended to assess RV function in HTX recipients. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Implanting intra-abdominal radiotransmitters with external whip antennas in ducks

    USGS Publications Warehouse

    Korschgen, C.E.; Kenow, K.P.; Gendron-Fitzpatrick, A.; Green, W.L.; Dein, F.J.

    1996-01-01

    We developed and evaluated a surgical procedure for implanting intra-abdominal radiotransmitters with external whip antennas in captive mallards (Anas platyrhynchos). Transmitters were implanted in the abdominal cavity and the antennas exited through the caudal abdominal wall and skin. Birds with implanted transmitters developed mild to moderate localized air sac reactions. These reactions involved adhesions of the right anterior abdominal air sac to the liver with contractions around the transmitters and antenna catheters. The adhesions were reinforced by a proliferation of connective tissue and lined by multinucleated giant cells (foreign body reaction). Casual observation indicated that neither behavior nor activity of the birds was altered by the histological reaction to the transmitter implant. No increase in systemic lesions (particularly liver or kidney) could be correlated with the histological reactions. Our evaluations indicate that the procedure is a reliable method for radiomarking ducks and the technique has been successfully used in 2 field studies.

  13. Temporary abdominal closure with zipper-mesh device for management of intra-abdominal sepsis.

    PubMed

    Utiyama, Edivaldo Massazo; Pflug, Adriano Ribeiro Meyer; Damous, Sérgio Henrique Bastos; Rodrigues, Adilson Costa; Montero, Edna Frasson de Souza; Birolini, Claudio Augusto Vianna

    2015-01-01

    to present our experience with scheduled reoperations in 15 patients with intra-abdominal sepsis. we have applied a more effective technique consisting of temporary abdominal closure with a nylon mesh sheet containing a zipper. We performed reoperations in the operating room under general anesthesia at an average interval of 84 hours. The revision consisted of debridement of necrotic material and vigorous lavage of the involved peritoneal area. The mean age of patients was 38.7 years (range, 15 to 72 years); 11 patients were male, and four were female. forty percent of infections were due to necrotizing pancreatitis. Sixty percent were due to perforation of the intestinal viscus secondary to inflammation, vascular occlusion or trauma. We performed a total of 48 reoperations, an average of 3.2 surgeries per patient. The mesh-zipper device was left in place for an average of 13 days. An intestinal ostomy was present adjacent to the zipper in four patients and did not present a problem for patient management. Mortality was 26.6%. No fistulas resulted from this technique. When intra-abdominal disease was under control, the mesh-zipper device was removed, and the fascia was closed in all patients. In three patients, the wound was closed primarily, and in 12 it was allowed to close by secondary intent. Two patients developed hernia; one was incisional and one was in the drain incision. the planned reoperation for manual lavage and debridement of the abdomen through a nylon mesh-zipper combination was rapid, simple, and well-tolerated. It permitted effective management of severe septic peritonitis, easy wound care and primary closure of the abdominal wall.

  14. The association between Chance fractures and intra-abdominal injuries revisited: a multicenter review.

    PubMed

    Tyroch, Alan H; McGuire, Emmett L; McLean, Susan F; Kozar, Rosemary A; Gates, Keith A; Kaups, Krista L; Cook, Charles; Cowgill, Sarah M; Griswold, John A; Sue, Larry A; Craun, Michael L; Price, Jan

    2005-05-01

    The association between Chance fractures and intra-abdominal injuries is reported to be as high as 89 per cent. Because prior studies were small series or case reports, we conducted a multicenter review to learn the true association between Chance fractures and intra-abdominal injuries as well as diagnostic trends. Trauma registry data, medical records, and radiology reports from 7 trauma centers were used to characterize 79 trauma patients with Chance fractures. Initial methods of abdominal assessment were computed tomography (CT) scan (79%), clinical examination (16%), and diagnostic peritoneal lavage (DPL) (5%). Twenty-six (33%) patients had intraabdominal injuries of which hollow viscus injuries predominated (22%). Twenty patients (25%) underwent laparotomy. The presence of an abdominal wall contusion and automobile restraint use were highly predictive of intra-abdominal injury and the need for laparotomy. The association between a Chance fracture and intra-abdominal injury is not as high as previously reported. CT scan has become the primary modality to assess the abdominal cavity of patients with Chance fractures, whereas the role of DPL has diminished.

  15. Experimental Study of Short-Time Brownian Motion

    NASA Astrophysics Data System (ADS)

    Mo, Jianyong; Simha, Akarsh; Riegler, David; Raizen, Mark

    2015-03-01

    We report our progress on the study of short-time Brownian motion of optically-trapped microspheres. In earlier work, we observed the instantaneous velocity of microspheres in gas and in liquid, verifying a prediction by Albert Einstein from 1907. We now report a more accurate test of the energy equipartition theorem for a particle in liquid. We also observe boundary effects on Brownian motion in liquid by setting a wall near the trapped particle, which changes the dynamics of the motion. We find that the velocity autocorrelation of the particle decreases faster as the particle gets closer to the wall.

  16. 18F-FDG uptake assessed by PET/CT in abdominal aortic aneurysms is associated with cellular and molecular alterations prefacing wall deterioration and rupture.

    PubMed

    Courtois, Audrey; Nusgens, Betty V; Hustinx, Roland; Namur, Gauthier; Gomez, Pierre; Somja, Joan; Defraigne, Jean-Olivier; Delvenne, Philippe; Michel, Jean-Baptiste; Colige, Alain C; Sakalihasan, Natzi

    2013-10-01

    Rupture of abdominal aortic aneurysms (AAAs) leads to a significant morbidity and mortality in aging populations, and its prediction would be most beneficial to public health. Spots positive for uptake of (18)F-FDG detected by PET are found in 12% of AAA patients (PET+), who are most often symptomatic and at high rupture risk. Comparing the (18)F-FDG-positive site with a negative site from the same aneurysm and with samples collected from AAA patients with no (18)F-FDG uptake should allow the discrimination of biologic alterations that would help in identifying markers predictive of rupture. Biopsies of the AAA wall were obtained from patients with no (18)F-FDG uptake (PET0, n = 10) and from PET+ patients (n = 8), both at the site positive for uptake and at a distant negative site of the aneurysmal wall. Samples were analyzed by immunohistochemistry, quantitative real-time polymerase chain reaction, and zymography. The sites of the aneurysmal wall with a positive (18)F-FDG uptake were characterized by a strikingly increased number of adventitial inflammatory cells, highly proliferative, and by a drastic reduction of smooth muscle cells (SMCs) in the media as compared with their negative counterpart and with the PET0 wall. The expression of a series of genes involved in the maintenance and remodeling of the wall was significantly modified in the negative sites of PET+, compared with the PET0 wall, suggesting a systemic alteration of the aneurysmal wall. Furthermore, a striking increase of several matrix metalloproteinases (MMPs), notably the MMP1 and MMP13 collagenases, was observed in the positive sites, mainly in the adventitia. Moreover, PET+ patients were characterized by a higher circulating C-reactive protein. Positive (18)F-FDG uptake in the aneurysmal wall is associated with an active inflammatory process characterized by a dense infiltrate of proliferating leukocytes in the adventitia and an increased circulating C-reactive protein. Moreover, a loss of SMC

  17. Propeller flap reconstruction of abdominal defects: review of the literature and case report.

    PubMed

    Scaglioni, Mario F; Giuseppe, Alberto Di; Chang, Edward I

    2015-01-01

    The abdominal wall is perfused anteriorly by the superior and deep epigastric vessels with a smaller contribution from the superficial system. The lateral abdominal wall is perfused predominantly from perforators arising from the intercostal vessels. Reconstruction of soft tissue defects involving the abdomen presents a difficult challenge for reconstructive surgeons. Pedicle perforator propeller flaps can be used to reconstruct defects of the abdomen, and here we present a thorough review of the literature as well as a case illustrating the perforasome propeller flap concept. A patient underwent resection for dermatofibrosarcoma protuberans resulting in a large defect of the epigastric soft tissue. A propeller flap was designed based on a perforator arising from the superior deep epigastric vessels and was rotated 90° into the defect allowing primary closure of the donor site. The patient healed uneventfully and was without recurrent disease 37 months following reconstruction. Perforator propeller flaps can be used successfully in reconstruction of abdominal defects and should be incorporated into the armamentarium of reconstructive microsurgeons already facile with perforator dissections. © 2014 Wiley Periodicals, Inc.

  18. Long-Term Outcomes after Abdominal Wall Reconstruction with Acellular Dermal Matrix.

    PubMed

    Garvey, Patrick B; Giordano, Salvatore A; Baumann, Donald P; Liu, Jun; Butler, Charles E

    2017-03-01

    Long-term outcomes data for hernia recurrence rates after abdominal wall reconstruction (AWR) with acellular dermal matrix (ADM) are lacking. The aim of this study was to assess the long-term durability of AWR using ADM. We studied patients who underwent AWR with ADM at a single center in 2005 to 2015 with a minimum follow-up of 36 months. Hernia recurrence was the primary end point and surgical site occurrence (SSO) was a secondary end point. The recurrence-free survival curves were estimated by Kaplan-Meier product limit method. Univariate and multivariable Cox proportional hazards regression models and logistic regression models were used to evaluate the associations of risk factors at surgery with subsequent risks for hernia recurrence and SSO, respectively. A total of 512 patients underwent AWR with ADM. After excluding those with follow-up less than 36 months, 191 patients were included, with a median follow-up of 52.9 months (range 36 to 104 months). Twenty-six of 191 patients had a hernia recurrence documented in the study. The cumulative recurrence rates were 11.5% at 3 years and 14.6% by 5 years. Factors significantly predictive of hernia recurrence developing included bridged repair, wound skin dehiscence, use of human cadaveric ADM, and coronary disease; component separation was protective. In a subset analysis excluding bridged repairs and human cadaveric ADM patients, cumulative hernia recurrence rates were 6.4% by 3 years and 8.3% by 5 years. The crude rate of SSO was 25.1% (48 of 191). Factors significantly predictive of the incidence of SSO included at least 1 comorbidity, BMI ≥30 kg/m 2 , and defect width >15 cm. Use of ADM for AWR was associated with 11.5% and 14.6% hernia recurrence rates at 3- and 5-years follow-up, respectively. Avoiding bridged repairs and human cadaveric ADM can improve long-term AWR outcomes using ADM. Copyright © 2016 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Correlation between spin structure oscillations and domain wall velocities

    PubMed Central

    Bisig, André; Stärk, Martin; Mawass, Mohamad-Assaad; Moutafis, Christoforos; Rhensius, Jan; Heidler, Jakoba; Büttner, Felix; Noske, Matthias; Weigand, Markus; Eisebitt, Stefan; Tyliszczak, Tolek; Van Waeyenberge, Bartel; Stoll, Hermann; Schütz, Gisela; Kläui, Mathias

    2013-01-01

    Magnetic sensing and logic devices based on the motion of magnetic domain walls rely on the precise and deterministic control of the position and the velocity of individual magnetic domain walls in curved nanowires. Varying domain wall velocities have been predicted to result from intrinsic effects such as oscillating domain wall spin structure transformations and extrinsic pinning due to imperfections. Here we use direct dynamic imaging of the nanoscale spin structure that allows us for the first time to directly check these predictions. We find a new regime of oscillating domain wall motion even below the Walker breakdown correlated with periodic spin structure changes. We show that the extrinsic pinning from imperfections in the nanowire only affects slow domain walls and we identify the magnetostatic energy, which scales with the domain wall velocity, as the energy reservoir for the domain wall to overcome the local pinning potential landscape. PMID:23978905

  20. Time-evolving of very large-scale motions in a turbulent channel flow

    NASA Astrophysics Data System (ADS)

    Hwang, Jinyul; Lee, Jin; Sung, Hyung Jin; Zaki, Tamer A.

    2014-11-01

    Direct numerical simulation (DNS) data of a turbulent channel flow at Reτ = 930 was scrutinized to investigate the formation of very large-scale motions (VLSMs) by merging of two large-scale motions (LSMs), aligned in the streamwise direction. We mainly focused on the supportive motions by the near-wall streaks during the merging of the outer LSMs. From visualization of the instantaneous flow fields, several low-speed streaks in the near-wall region were collected in the spanwise direction, when LSMs were concatenated in the outer region. The magnitude of the streamwise velocity fluctuations in the streaks was intensified during the spanwise merging of the near-wall streaks. Conditionally-averaged velocity fields around the merging of the outer LSMs showed that the intensified near-wall motions were induced by the outer LSMs and extended over the near-wall regions. The intense near-wall motions influence the formation of the outer low-speed regions as well as the reduction of the convection velocity of the downstream LSMs. The interaction between the near-wall and the outer motions is the essential origin of the different convection velocities of the upstream and downstream LSMs for the formation process of VLSMs by merging. This work was supported by the Creative Research Initiatives (No. 2014-001493) program of the National Research Foundation of Korea (MSIP) and partially supported by KISTI under the Strategic Supercomputing Support Program.

  1. 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.

  2. 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. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Virtual modeling of robot-assisted manipulations in abdominal surgery.

    PubMed

    Berelavichus, Stanislav V; Karmazanovsky, Grigory G; Shirokov, Vadim S; Kubyshkin, Valeriy A; Kriger, Andrey G; Kondratyev, Evgeny V; Zakharova, Olga P

    2012-06-27

    To determine the effectiveness of using multidetector computed tomography (MDCT) data in preoperative planning of robot-assisted surgery. Fourteen patients indicated for surgery underwent MDCT using 64 and 256-slice MDCT. Before the examination, a specially constructed navigation net was placed on the patient's anterior abdominal wall. Processing of MDCT data was performed on a Brilliance Workspace 4 (Philips). Virtual vectors that imitate robotic and assistant ports were placed on the anterior abdominal wall of the 3D model of the patient, considering the individual anatomy of the patient and the technical capabilities of robotic arms. Sites for location of the ports were directed by projection on the roentgen-positive tags of the navigation net. There were no complications observed during surgery or in the post-operative period. We were able to reduce robotic arm interference during surgery. The surgical area was optimal for robotic and assistant manipulators without any need for reinstallation of the trocars. This method allows modeling of the main steps in robot-assisted intervention, optimizing operation of the manipulator and lowering the risk of injuries to internal organs.

  4. Effects of abdominal pressure on venous return: abdominal vascular zone conditions.

    PubMed

    Takata, M; Wise, R A; Robotham, J L

    1990-12-01

    The effects of changes in abdominal pressure (Pab) on inferior vena cava (IVC) venous return were analyzed using a model of the IVC circulation based on a concept of abdominal vascular zone conditions analogous to pulmonary vascular zone conditions. We hypothesized that an increase in Pab would increase IVC venous return when the IVC pressure at the level of the diaphragm (Pivc) exceeds the sum of Pab and the critical closing transmural pressure (Pc), i.e., zone 3 conditions, but reduce IVC venous return when Pivc is below the sum of Pab and Pc, i.e., zone 2 conditions. The validity of the model was tested in 12 canine experiments with an open-chest IVC bypass. An increase in Pab produced by phrenic stimulation increased the IVC venous return when Pivc-Pab was positive but decreased the IVC venous return when Pivc - Pab was negative. The value of Pivc - Pab that separated net increases from decreases in venous return was 1.00 +/- 0.72 (SE) mmHg (n = 6). An increase in Pivc did not influence the femoral venous pressure when Pivc was lower than the sum of Pab and a constant, 0.96 +/- 0.70 mmHg (n = 6), consistent with presence of a waterfall. These results agreed closely with the predictions of the model and its computer simulation. The abdominal venous compartment appears to function with changes in Pab either as a capacitor in zone 3 conditions or as a collapsible Starling resistor with little wall tone in zone 2 conditions.

  5. Skyrmion domain wall collision and domain wall-gated skyrmion logic

    NASA Astrophysics Data System (ADS)

    Xing, Xiangjun; Pong, Philip W. T.; Zhou, Yan

    2016-08-01

    Skyrmions and domain walls are significant spin textures of great technological relevance to magnetic memory and logic applications, where they can be used as carriers of information. The unique topology of skyrmions makes them display emergent dynamical properties as compared with domain walls. Some studies have demonstrated that the two topologically inequivalent magnetic objects could be interconverted by using cleverly designed geometric structures. Here, we numerically address the skyrmion domain wall collision in a magnetic racetrack by introducing relative motion between the two objects based on a specially designed junction. An electric current serves as the driving force that moves a skyrmion toward a trapped domain wall pair. We see different types of collision dynamics depending on the driving parameters. Most importantly, the modulation of skyrmion transport using domain walls is realized in this system, allowing a set of domain wall-gated logical NOT, NAND, and NOR gates to be constructed. This work provides a skyrmion-based spin-logic architecture that is fully compatible with racetrack memories.

  6. Image-Guided Abdominal Surgery and Therapy Delivery

    PubMed Central

    Galloway, Robert L.; Herrell, S. Duke; Miga, Michael I.

    2013-01-01

    Image-Guided Surgery has become the standard of care in intracranial neurosurgery providing more exact resections while minimizing damage to healthy tissue. Moving that process to abdominal organs presents additional challenges in the form of image segmentation, image to physical space registration, organ motion and deformation. In this paper, we present methodologies and results for addressing these challenges in two specific organs: the liver and the kidney. PMID:25077012

  7. Current induced domain wall motion in antiferromagnetically coupled (Co70Fe30/Pd) multilayer nanowires

    NASA Astrophysics Data System (ADS)

    Meng, Zhaoliang; He, Shikun; Huang, Lisen; Qiu, Jinjun; Zhou, Tiejun; Panagopoulos, Christos; Han, Guchang; Teo, Kie-Leong

    2016-10-01

    We investigate the current induced domain wall (DW) motion in the ultrathin CoFe/Pd multilayer based synthetically antiferromagnetic (SAF) structure nanowires by anomalous Hall effect measurement. The threshold current density (Jth) for the DW displacement decreases and the DW velocity (v) increases accordingly with the exchange coupling Jex between the top and bottom ferromagnetic CoFe/Pd multilayers. The lowest Jth = 9.3 × 1010 A/m2 and a maximum v = 150 m/s with J = 1.5 × 1012 A/m2 are achieved due to the exchange coupling torque (ECT) generated in the SAF structure. The strength of ECT is dependent on both of Jex and the strong spin-orbit torque mainly generated by Ta layer.

  8. Induced transducer orientation during ultrasound imaging: effects on abdominal muscle thickness and bladder position.

    PubMed

    Whittaker, Jackie L; Warner, Martin B; Stokes, Maria J

    2009-11-01

    The use of ultrasound imaging (USI) by physiotherapists to assess muscle behavior in clinical settings is increasing. However, there is relatively little evidence of whether the clinical environment is conducive to valid and reliable measurements. Accurate USI measurements depend on maintaining a relatively stationary transducer position, because motion may distort the image and lead to erroneous conclusions. This would seem particularly important during dynamic studies typical of a physiotherapy assessment. What is not known is how much transducer motion can occur before error is introduced. The aim of this study is to shed some light on this question. Eight healthy volunteers (19 to 52 y) participated. USI images were taken of the lateral abdominal wall (LAW) and bladder base (midline suprapubic) at various manually induced transducer orientations (approximately -10 to 10 degrees about 3 axes of rotation), which were quantified by a digital optical motion capture system. Measurements of transversus abdominis (TrA) thickness and bladder base position (cranial /caudal and anterior/posterior) were calculated. Repeated measures analysis of variance was performed to determine if the measurements obtained at the induced transducer orientations were statistically different (p<0.05) from an image corresponding to a reference or starting transducer orientation. Motion analysis data corresponding to measurements that did not differ from reference image measurements were summarized to provide a range of acceptable transducer motion (relative to the pelvis) for clockwise (CW)/counter-clockwise (CCW) rotation, cranial/caudal tilting, medial/lateral tilting and inward/outward displacement. There were no significant changes in TrA thickness measurements if CW/CCW transducer motion was <9 degrees and cranial/caudal or medial/lateral transducer tilting was <5 degrees . Further, there were no significant changes in measurements of bladder base position if CW/CCW transducer motion

  9. An integrated model-based software for FUS in moving abdominal organs.

    PubMed

    Schwenke, Michael; Strehlow, Jan; Haase, Sabrina; Jenne, Juergen; Tanner, Christine; Langø, Thomas; Loeve, Arjo J; Karakitsios, Ioannis; Xiao, Xu; Levy, Yoav; Sat, Giora; Bezzi, Mario; Braunewell, Stefan; Guenther, Matthias; Melzer, Andreas; Preusser, Tobias

    2015-05-01

    Focused ultrasound surgery (FUS) is a non-invasive method for tissue ablation that has the potential for complete and controlled local tumour destruction with minimal side effects. The treatment of abdominal organs such as the liver, however, requires particular technological support in order to enable a safe, efficient and effective treatment. As FUS is applied from outside the patient's body, suitable imaging methods, such as magnetic resonance imaging or diagnostic ultrasound, are needed to guide and track the procedure. To facilitate an efficient FUS procedure in the liver, the organ motion during breathing and the partial occlusion by the rib cage need to be taken into account in real time, demanding a continuous patient-specific adaptation of the treatment configuration. Modelling the patient's respiratory motion and combining this with tracking data improves the accuracy of motion predictions. Modelling and simulation of the FUS effects within the body allows the use of treatment planning and has the potential to be used within therapy to increase knowledge about the patient status. This article describes integrated model-based software for patient-specific modelling and prediction for FUS treatments of moving abdominal organs.

  10. Biomechanical and histologic evaluation of two application forms of surgical glue for mesh fixation to the abdominal wall.

    PubMed

    Ortillés, Á; Pascual, G; Peña, E; Rodríguez, M; Pérez-Köhler, B; Mesa-Ciller, C; Calvo, B; Bellón, J M

    2017-11-01

    The use of an adhesive for mesh fixation in hernia repair reduces chronic pain and minimizes tissue damage in the patient. This study was designed to assess the adhesive properties of a medium-chain (n-butyl) cyanoacrylate glue applied as drops or as a spray in a biomechanical and histologic study. Both forms of glue application were compared to the use of simple-loose or continuous-running polypropylene sutures for mesh fixation. Eighteen adult New Zealand White rabbits were used. For mechanical tests in an ex vivo and in vivo study, patches of polypropylene mesh were fixed to an excised fragment of healthy abdominal tissue or used to repair a partial abdominal wall defect in the rabbit respectively. Depending on the fixation method used, four groups of 12 implants each or 10 implants each respectively for the ex vivo and in vivo studies were established: Glue-Drops, Glue-Spray, Suture-Simple and Suture-Continuous. Biomechanical resistance in the ex vivo implants was tested five minutes after mesh fixation. In vivo implants for biomechanical and histologic assessment were collected at 14 days postimplant. In the ex vivo study, the continuous suture implants showed the highest failure sample tension, while the implants fixed with glue showed lower failure sample tension values. However, the simple and continuous suture implants returned the highest stretch values. In the in vivo implants, failure sample tension values were similar among groups while the implants fixed with a continuous running suture had the higher stretch values, and the glue-fixed implants the lower stretch values. All meshes showed good tissue integration within the host tissue regardless of the fixation method used. Our histologic study revealed the generation of a denser, more mature repair tissue when the cyanoacrylate glue was applied as a spray rather than as drops. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. MO-FG-CAMPUS-JeP3-04: Feasibility Study of Real-Time Ultrasound Monitoring for Abdominal Stereotactic Body Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Su, Lin; Kien Ng, Sook; Zhang, Ying

    Purpose: Ultrasound is ideal for real-time monitoring in radiotherapy with high soft tissue contrast, non-ionization, portability, and cost effectiveness. Few studies investigated clinical application of real-time ultrasound monitoring for abdominal stereotactic body radiation therapy (SBRT). This study aims to demonstrate the feasibility of real-time monitoring of 3D target motion using 4D ultrasound. Methods: An ultrasound probe holding system was designed to allow clinician to freely move and lock ultrasound probe. For phantom study, an abdominal ultrasound phantom was secured on a 2D programmable respiratory motion stage. One side of the stage was elevated than another side to generate 3D motion.more » The motion stage made periodic breath-hold movement. Phantom movement tracked by infrared camera was considered as ground truth. For volunteer study three healthy subjects underwent the same setup for abdominal SBRT with active breath control (ABC). 4D ultrasound B-mode images were acquired for both phantom and volunteers for real-time monitoring. 10 breath-hold cycles were monitored for each experiment. For phantom, the target motion tracked by ultrasound was compared with motion tracked by infrared camera. For healthy volunteers, the reproducibility of ABC breath-hold was evaluated. Results: Volunteer study showed the ultrasound system fitted well to the clinical SBRT setup. The reproducibility for 10 breath-holds is less than 2 mm in three directions for all three volunteers. For phantom study the motion between inspiration and expiration captured by camera (ground truth) is 2.35±0.02 mm, 1.28±0.04 mm, 8.85±0.03 mm in LR, AP, SI directly, respectively. The motion monitored by ultrasound is 2.21±0.07 mm, 1.32±0.12mm, 9.10±0.08mm, respectively. The motion monitoring error in any direction is less than 0.5 mm. Conclusion: The volunteer study proved the clinical feasibility of real-time ultrasound monitoring for abdominal SBRT. The phantom and volunteer

  12. Mechanics, Mechanobiology, and Modeling of Human Abdominal Aorta and Aneurysms

    PubMed Central

    Humphrey, J.D.; Holzapfel, G.A.

    2011-01-01

    Biomechanical factors play fundamental roles in the natural history of abdominal aortic aneurysms (AAAs) and their responses to treatment. Advances during the past two decades have increased our understanding of the mechanics and biology of the human abdominal aorta and AAAs, yet there remains a pressing need for considerable new data and resulting patient-specific computational models that can better describe the current status of a lesion and better predict the evolution of lesion geometry, composition, and material properties and thereby improve interventional planning. In this paper, we briefly review data on the structure and function of the human abdominal aorta and aneurysmal wall, past models of the mechanics, and recent growth and remodeling models. We conclude by identifying open problems that we hope will motivate studies to improve our computational modeling and thus general understanding of AAAs. PMID:22189249

  13. Predictive Factors in the Outcome of Surgical Repair of Abdominal Rectus Diastasis.

    PubMed

    Strigård, Karin; Clay, Leonard; Stark, Birgit; Gunnarsson, Ulf

    2016-05-01

    The aim of this study was to define the indicators predicting improved abdominal wall function after surgical repair of abdominal rectus diastasis (ARD). Preoperative subjective assessment quantified by the validated Ventral Hernia Pain Questionnaire (VHPQ) was related to relative postoperative functional improvement in abdominal muscle strength. Fifty-seven patients undergoing surgery for ARD completed the VHPQ before surgery. Preoperative pain assessment results were compared with the relative improvement in muscle strength measured with the BioDex system 4. There was a correlation between the relative improvement in muscle strength measured by the BioDex System 4 for flexion at 30 degrees (P = 0.046) and 60 degrees per second (P = 0.004) and the preoperative question, "Do you find it painful to sit for more than 30 minutes?" There was also a correlation between BioDex improvement for flexion at 30 degrees (P = 0.022) and for isometric work load (P = 0.038) and the preoperative question, "Has abdominal pain limited your ability to perform sports activities?" The VHPQ responses also formed a pattern with a fairly good correlation between other BioDex modalities (with the exception of extension at 60 degrees per second) and the response to the question regarding complaints when performing sports. Postoperative visual analog scale ratings of abdominal wall stability correlated to the questions regarding complaints when sitting (P = 0.040) and standing (P = 0.047). No other correlation was seen. VHPQ ratings concerning pain while being seated for more than 30 minutes and pain limiting the ability to perform sports are promising indicators in the identification of patients likely to benefit from surgical correction of their ARD.

  14. Abdominal Adhesions

    MedlinePlus

    ... Clearinghouse What are abdominal adhesions? Abdominal adhesions are bands of fibrous tissue that can form between abdominal ... Esophagus Stomach Large intestine Adhesion Abdominal adhesions are bands of fibrous tissue that can form between abdominal ...

  15. Abdominal Pain

    MedlinePlus

    ... and Recurrent or Functional Abdominal Pain (RAP or FAP) What is abdominal pain? Abdominal pain , or stomachache, ... recurrent abdominal pain (RAP) or functional abdominal pain (FAP)? If your health care provider has ruled out ...

  16. Development of the ventral body wall in the human embryo

    PubMed Central

    Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Köhler, S Eleonore; Lamers, Wouter H

    2015-01-01

    Migratory failure of somitic cells is the commonest explanation for ventral body wall defects. However, the embryo increases ∼ 25-fold in volume in the period that the ventral body wall forms, so that differential growth may, instead, account for the observed changes in topography. Human embryos between 4 and 10 weeks of development were studied, using amira® reconstruction and cinema 4D® remodeling software for visualization. Initially, vertebrae and ribs had formed medially, and primordia of sternum and hypaxial flank muscle primordium laterally in the body wall at Carnegie Stage (CS)15 (5.5 weeks). The next week, ribs and muscle primordium expanded in ventrolateral direction only. At CS18 (6.5 weeks), separate intercostal and abdominal wall muscles differentiated, and ribs, sterna, and muscles began to expand ventromedially and caudally, with the bilateral sternal bars fusing in the midline after CS20 (7 weeks) and the rectus muscles reaching the umbilicus at CS23 (8 weeks). The near-constant absolute distance between both rectus muscles and approximately fivefold decline of this distance relative to body circumference between 6 and 10 weeks identified dorsoventral growth in the dorsal body wall as determinant of the ‘closure’ of the ventral body wall. Concomitant with the straightening of the embryonic body axis after the 6th week, the abdominal muscles expanded ventrally and caudally to form the infraumbilical body wall. Our data, therefore, show that the ventral body wall is formed by differential dorsoventral growth in the dorsal part of the body. PMID:26467243

  17. Comparison between collective coordinate models for domain wall motion in PMA nanostrips in the presence of the Dzyaloshinskii-Moriya interaction

    NASA Astrophysics Data System (ADS)

    Vandermeulen, J.; Nasseri, S. A.; Van de Wiele, B.; Durin, G.; Van Waeyenberge, B.; Dupré, L.

    2018-03-01

    Lagrangian-based collective coordinate models for magnetic domain wall (DW) motion rely on an ansatz for the DW profile and a Lagrangian approach to describe the DW motion in terms of a set of time-dependent collective coordinates: the DW position, the DW magnetization angle, the DW width and the DW tilting angle. Another approach was recently used to derive similar equations of motion by averaging the Landau-Lifshitz-Gilbert equation without any ansatz, and identifying the relevant collective coordinates afterwards. In this paper, we use an updated version of the semi-analytical equations to compare the Lagrangian-based collective coordinate models with micromagnetic simulations for field- and STT-driven (spin-transfer torque-driven) DW motion in Pt/CoFe/MgO and Pt/Co/AlOx nanostrips. Through this comparison, we assess the accuracy of the different models, and provide insight into the deviations of the models from simulations. It is found that the lack of terms related to DW asymmetry in the Lagrangian-based collective coordinate models significantly contributes to the discrepancy between the predictions of the most accurate Lagrangian-based model and the micromagnetic simulations in the field-driven case. This is in contrast to the STT-driven case where the DW remains symmetric.

  18. Scrub typhus associated hepatic dysfunction and abdominal CT findings

    PubMed Central

    Park, Man Je; Lee, Hyoun Soo; Shim, Sang Goon; Kim, So Hee

    2015-01-01

    Objective: This retrospective study investigated abnormal hepatic dysfunction and abdominal computed tomography (CT) findings in scrub typhus. Methods: Three hundred forty nine adult patients were diagnosed with scrub typhus. Ninety four underwent abdominal CT. The CT images were reviewed by the attending radiologist. Patient data of history, symptoms, signs, and results of laboratory tests were collected from the electronic medical records. Results: In 349 patients with scrub typhus, elevation of aspartate aminotransferase (78.5%) and alanine aminotransferase (63.0%) were dominant compared to alkaline phosphatase (27.2%) and total bilirubin (16.1%). Abdominal CT findings of 94 patients were, in descending order of frequency, enlarged lymph node (53.2%), inhomogeneous enhancement of liver (47.9%), splenomegaly (46.8%), ascites (28.7%), low attenuation of periportal areas (27.7%), gallbladder wall thickening (17.0%), and splenic infarct (6.4%). Also, the level of aspartate aminotransferase tended to be elevated according to the number of CT findings (P= 0.028) Conclusions: We found that abdominal CT manifestations of scrub typhus with elevated aminotransferases were varied and not specific. However, knowledge of these findings may evoke the recognition of scrub typhus by clinicians in endemic areas. PMID:26101478

  19. Ultrasound in the diagnosis of palpable abdominal masses in children.

    PubMed

    Annuar, Z; Sakijan, A S; Annuar, N; Kooi, G H

    1990-12-01

    Ultrasound examinations were done to evaluate clinically palpable abdominal masses in 125 children. The examinations were normal in 21 patients. In 15 patients, the clinically palpable masses were actually anterior abdominal wall abscesses or hematomas. Final diagnosis was available in 87 of 89 patients with intraabdominal masses detected on ultrasound. The majority (71%) were retroperitoneal masses where two-thirds were of renal origin. Ultrasound diagnosis was correct in 68 patients (78%). All cases of hydronephrosis were correctly diagnosed based on characteristic ultrasound appearances. Correct diagnoses of all cases of adrenal hematoma, psoas abscess, liver hematoma, liver abscess and one case of liver metastases were achieved with correlation of relevant clinical information.

  20. Activation amplitude and temporal synchrony among back extensor and abdominal muscles during a controlled transfer task: comparison of men and women.

    PubMed

    Hubley-Kozey, Cheryl L; Butler, Heather L; Kozey, John W

    2012-08-01

    Muscle synergies are important for spinal stability, but few studies examine temporal responses of spinal muscles to dynamic perturbations. This study examined activation amplitudes and temporal synergies among compartments of the back extensor and among abdominal wall muscles in response to dynamic bidirectional moments of force. We further examined whether responses were different between men and women. 19 women and 18 men performed a controlled transfer task. Surface electromyograms from bilateral sites over 6 back extensor compartments and 6 abdominal wall muscle sites were analyzed using principal component analysis. Key features were extracted from the measured electromyographic waveforms capturing amplitude and temporal variations among muscle sites. Three features explained 97% of the variance. Scores for each feature were computed for each measured waveform and analysis of variance found significant (p<.05) muscle main effects and a sex by muscle interaction. For the back extensors, post hoc analysis revealed that upper and more medial sites were recruited to higher amplitudes, medial sites responded to flexion moments, and the more lateral sites responded to lateral flexion moments. Women had more differences among muscle sites than men for the lateral flexion moment feature. For the abdominal wall muscles the oblique muscles responded with synergies related to fiber orientation, with women having higher amplitudes and more responsiveness to the lateral flexion moment than men. Synergies between the abdominal and back extensor sites as the moment demands change are discussed. These findings illustrate differential activation among erector spinae compartments and abdominal wall muscle sites supporting a highly organized pattern of response to bidirectional external moments with asynchronies more apparent in women. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Factors Predictive of Improved Abdominal Ultrasound Visualization after Oral Administration of Simethicone.

    PubMed

    Marsico, Maria; Gabbani, Tommaso; Casseri, Tommaso; Biagini, Maria Rosa

    2016-11-01

    Ultrasonography is a non-invasive, accurate and low-cost technique used to study the upper abdomen, but it has reduced reliability in the study of the pancreas and retroperitoneum. Simethicone is a well-known emulsifying agent that has been used to improve ultrasonographic visualization. The aim of this study was to identify anthropometric parameters that are able to predict a good response to simethicone in improving ultrasonographic visualization of abdominal structures. One hundred twenty-seven patients were recruited. After basal examination, their anthropometric parameters were collected. Patients with an incomplete upper abdominal examination because of gastrointestinal gas have greater body mass index, waist circumference and abdominal wall thickness. In our study, the best anthropometric parameter for identifying patients with poor visualization at abdominal ultrasound examination is waist circumference. Using a cutoff of 84 cm, we can identify patients with poor visibility at abdominal ultrasound examination (group B) with a sensitivity of 90%. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  2. A two-system, single-analysis, fluid-structure interaction technique for modelling abdominal aortic aneurysms.

    PubMed

    Kelly, S C; O'Rourke, M J

    2010-01-01

    This work reports on the implementation and validation of a two-system, single-analysis, fluid-structure interaction (FSI) technique that uses the finite volume (FV) method for performing simulations on abdominal aortic aneurysm (AAA) geometries. This FSI technique, which was implemented in OpenFOAM, included fluid and solid mesh motion and incorporated a non-linear material model to represent AAA tissue. Fully implicit coupling was implemented, ensuring that both the fluid and solid domains reached convergence within each time step. The fluid and solid parts of the FSI code were validated independently through comparison with experimental data, before performing a complete FSI simulation on an idealized AAA geometry. Results from the FSI simulation showed that a vortex formed at the proximal end of the aneurysm during systolic acceleration, and moved towards the distal end of the aneurysm during diastole. Wall shear stress (WSS) values were found to peak at both the proximal and distal ends of the aneurysm and remain low along the centre of the aneurysm. The maximum von Mises stress in the aneurysm wall was found to be 408kPa, and this occurred at the proximal end of the aneurysm, while the maximum displacement of 2.31 mm occurred in the centre of the aneurysm. These results were found to be consistent with results from other FSI studies in the literature.

  3. Meta-analysis of peak wall stress in ruptured, symptomatic and intact abdominal aortic aneurysms.

    PubMed

    Khosla, S; Morris, D R; Moxon, J V; Walker, P J; Gasser, T C; Golledge, J

    2014-10-01

    Abdominal aortic aneurysm (AAA) is an important cause of sudden death; however, there are currently incomplete means to predict the risk of AAA rupture. AAA peak wall stress (PWS) can be estimated using finite element analysis (FEA) methods from computed tomography (CT) scans. The question is whether AAA PWS can predict AAA rupture. The aim of this systematic review was to compare PWS in patients with ruptured and intact AAA. The MEDLINE database was searched on 25 May 2013. Case-control studies assessing PWS in asymptomatic intact, and acutely symptomatic or ruptured AAA from CT scans using FEA were included. Data were extracted independently. A random-effects model was used to calculate standard mean differences (SMDs) for PWS measurements. Nine studies assessing 348 individuals were identified and used in the meta-analysis. Results from 204 asymptomatic intact and 144 symptomatic or ruptured AAAs showed that PWS was significantly greater in the symptomatic/ ruptured AAAs compared with the asymptomatic intact AAAs (SMD 0·95, 95 per cent confidence interval 0·71 to 1·18; P < 0·001). The findings remained significant after adjustment for mean systolic blood pressure, standardized at 120 mmHg (SMD 0·68, 0·39 to 0·96; P < 0·001). Minimal heterogeneity between studies was noted (I(2)  = 0 per cent). This study suggests that PWS is greater in symptomatic or ruptured AAA than in asymptomatic intact AAA. © 2014 BJS Society Ltd. Published by John Wiley & Sons Ltd.

  4. [The etiological aspects of acute abdominal pain in children].

    PubMed

    Dinu, C A; Moraru, D

    2011-01-01

    The study of the etiological aspects of acute abdominal pain in children, in order to perceive the clinical-etiological correlations and the disorders distribution related to age, gender and the origin of the patients. The criteria for including patients were age (between 0 and 18 years) and the presence of acute abdominal pain before or during the consultation with the physician. The research on acute abdominal pain in children was performed on the level of the Surgery and Pediatrics II clinical departments of the "Sf. Ioan" Children's Emergency Clinical Hospital in Galati, between 01.01.2009 - 01.01.2011. The clinical study performed on the patients registered in the studied groups focused on the identification, the evaluation of the symptoms of acute abdominal pain in children, diagnosing and treating it. The criteria for excluding patients were an age older than 18 years or the absence of acute abdominal pain as a symptom before or during the examination. The statistical analysis used the descriptive and analytical methods. The data was centralized and statistically processed in M.S.EXCEL and S.P.S.S. databases. The patients with acute abdominal pain represent a percentage of 92.9% (2358 cases) of the total number of patients who suffer from abdominal pain (N=2537). The highest frequency of cases is represented by acute appendicitis (1056 cases - 44.8%). In the 5-18 years age group, acute appendicitis, mesenteric lymphadenitis, ovarian follicular cysts, acute pyelenophritis and salpingitis are predominant. In the 0-4 years age group gastroenteritis, acute pharyngitis, reactive hepatitis and lower digestive bleeding are predominant. In females, acute appendicitis, gastroenteritis, gastroduodenitis and cystitis are predominant, whereas in males, peritonitis, sepsis through E. coli, the contusion of the abdominal wall and acute pharyngitis are predominant.

  5. Coexistence of bounded and unbounded motions in a bouncing ball model

    NASA Astrophysics Data System (ADS)

    Marò, Stefano

    2013-05-01

    We consider the model describing the vertical motion of a ball falling with constant acceleration on a wall and elastically reflected. The wall is supposed to move in the vertical direction according to a given periodic function f. We apply the Aubry-Mather theory to the generating function in order to prove the existence of bounded motions with prescribed mean time between the bounces. As the existence of unbounded motions is known, it is possible to find a class of functions f that allow both bounded and unbounded motions.

  6. [Abdominal bloating: an up-to-date].

    PubMed

    Ducrotté, P

    2009-10-01

    Bloating is a common symptom, especially in women. In the clinical practice, it remains a therapeutic challenge. Since recently, its pathophysiology is better understood: an impaired transit of gas (particularly in the small bowel) or a visceral hypersensitivity leading to the induction of an abdominal discomfort despite a normal volume of gas are two of the main causes, far more frequent than an excessive production of gas. Moreover, bloating can be related to abnormal viscera-somatic reflexes promoting both an abdomino-phrenic dyssynergia and the relaxation of the muscles of the abdominal wall. From a therapeutic point of view, the efficacy of the gas absorbants remains to be more documented. Besides the treatment of a constipation and the avoidance of nutrients either highly fermentable or rich in fructose, other therapeutic options include prokinetics and drugs acting on visceral sensitivity. Probiotics are another promising option. In some centers, a non pharmacological therapeutic approach, mainly based on hypnosis, is discussed.

  7. Aortic dissection simulation models for clinical support: fluid-structure interaction vs. rigid wall models.

    PubMed

    Alimohammadi, Mona; Sherwood, Joseph M; Karimpour, Morad; Agu, Obiekezie; Balabani, Stavroula; Díaz-Zuccarini, Vanessa

    2015-04-15

    The management and prognosis of aortic dissection (AD) is often challenging and the use of personalised computational models is being explored as a tool to improve clinical outcome. Including vessel wall motion in such simulations can provide more realistic and potentially accurate results, but requires significant additional computational resources, as well as expertise. With clinical translation as the final aim, trade-offs between complexity, speed and accuracy are inevitable. The present study explores whether modelling wall motion is worth the additional expense in the case of AD, by carrying out fluid-structure interaction (FSI) simulations based on a sample patient case. Patient-specific anatomical details were extracted from computed tomography images to provide the fluid domain, from which the vessel wall was extrapolated. Two-way fluid-structure interaction simulations were performed, with coupled Windkessel boundary conditions and hyperelastic wall properties. The blood was modelled using the Carreau-Yasuda viscosity model and turbulence was accounted for via a shear stress transport model. A simulation without wall motion (rigid wall) was carried out for comparison purposes. The displacement of the vessel wall was comparable to reports from imaging studies in terms of intimal flap motion and contraction of the true lumen. Analysis of the haemodynamics around the proximal and distal false lumen in the FSI model showed complex flow structures caused by the expansion and contraction of the vessel wall. These flow patterns led to significantly different predictions of wall shear stress, particularly its oscillatory component, which were not captured by the rigid wall model. Through comparison with imaging data, the results of the present study indicate that the fluid-structure interaction methodology employed herein is appropriate for simulations of aortic dissection. Regions of high wall shear stress were not significantly altered by the wall motion

  8. Adventitial adipogenic degeneration is an unidentified contributor to aortic wall weakening in the abdominal aortic aneurysm.

    PubMed

    Doderer, Stefan A; Gäbel, Gabor; Kokje, Vivianne B C; Northoff, Bernd H; Holdt, Lesca M; Hamming, Jaap F; Lindeman, Jan H N

    2018-06-01

    The processes driving human abdominal aortic aneurysm (AAA) progression are not fully understood. Although antiinflammatory and proteolytic strategies effectively quench aneurysm progression in preclinical models, so far all clinical interventions failed. These observations hint at an incomplete understanding of the processes involved in AAA progression and rupture. Interestingly, strong clinical and molecular associations exist between popliteal artery aneurysms (PAAs) and AAAs; however, PAAs have an extremely low propensity to rupture. We thus reasoned that differences between these aneurysms may provide clues toward (auxiliary) processes involved in AAA-related wall debilitation. A better understanding of the pathophysiologic processes driving AAA growth can contribute to pharmaceutical treatments in the future. Aneurysmal wall samples were collected during open elective and emergency repair. Control perirenal aorta was obtained during kidney transplantation, and reference popliteal tissue obtained from the anatomy department. This study incorporates various techniques including (immuno)histochemistry, Western Blot, quantitative polymerase chain reaction, microarray, and cell culture. Histologic evaluation of AAAs, PAAs, and control aorta shows extensive medial (PAA) and transmural fibrosis (AAA), and reveals abundant adventitial adipocytes aggregates as an exclusive phenomenon of AAAs (P < .001). Quantitative polymerase chain reaction, immunohistochemistry, Western blotting, and microarray analysis showed enrichment of adipogenic mediators (C/EBP family P = .027; KLF5 P < .000; and peroxisome proliferator activated receptor-γ, P = .032) in AAA tissue. In vitro differentiation tests indicated a sharply increased adipogenic potential of AAA adventitial mesenchymal cells (P < .0001). Observed enrichment of adipocyte-related genes and pathways in ruptured AAA (P < .0003) supports an association between the extent of fatty degeneration and rupture. This

  9. Actinomycotic abscess of the anterior abdominal wall: a case report and literature review.

    PubMed

    Pitot, D; De Moor, V; Demetter, P; Place, S; Gelin, M; El Nakadi, I

    2008-01-01

    Actinomycosis is a rare, chronic, suppurative, pseudotumoral illness caused by an anaerobic gram positive organism usually Actinomyces israelii which can mimick a tumoral pathology leading to a mutilating surgical resection. We report a case of abdominal actinomycosis and a literature review.

  10. Motion management within two respiratory-gating windows: feasibility study of dual quasi-breath-hold technique in gated medical procedures

    NASA Astrophysics Data System (ADS)

    Kim, Taeho; Kim, Siyong; Park, Yang-Kyun; Youn, Kaylin K.; Keall, Paul; Lee, Rena

    2014-11-01

    A dual quasi-breath-hold (DQBH) technique is proposed for respiratory motion management (a hybrid technique combining breathing-guidance with breath-hold task in the middle). The aim of this study is to test a hypothesis that the DQBH biofeedback system improves both the capability of motion management and delivery efficiency. Fifteen healthy human subjects were recruited for two respiratory motion measurements (free breathing and DQBH biofeedback breathing for 15 min). In this study, the DQBH biofeedback system utilized the abdominal position obtained using an real-time position management (RPM) system (Varian Medical Systems, Palo Alto, USA) to audio-visually guide a human subject for 4 s breath-hold at EOI and 90% EOE (EOE90%) to improve delivery efficiency. We investigated the residual respiratory motion and the delivery efficiency (duty-cycle) of abdominal displacement within the gating window. The improvement of the abdominal motion reproducibility was evaluated in terms of cycle-to-cycle displacement variability, respiratory period and baseline drift. The DQBH biofeedback system improved the abdominal motion management capability compared to that with free breathing. With a phase based gating (mean ± std: 55  ±  5%), the averaged root mean square error (RMSE) of the abdominal displacement in the dual-gating windows decreased from 2.26 mm of free breathing to 1.16 mm of DQBH biofeedback (p-value = 0.007). The averaged RMSE of abdominal displacement over the entire respiratory cycles reduced from 2.23 mm of free breathing to 1.39 mm of DQBH biofeedback breathing in the dual-gating windows (p-value = 0.028). The averaged baseline drift dropped from 0.9 mm min-1 with free breathing to 0.09 mm min-1 with DQBH biofeedback (p-value = 0.048). The averaged duty-cycle with an 1 mm width of displacement bound increased from 15% of free breathing to 26% of DQBH biofeedback (p-value = 0.003). The study demonstrated that the DQBH biofeedback

  11. Abdominal tap

    MedlinePlus

    Peritoneal tap; Paracentesis; Ascites - abdominal tap; Cirrhosis - abdominal tap; Malignant ascites - abdominal tap ... abdominal cavity ( most often cancer of the ovaries ) Cirrhosis of the liver Damaged bowel Heart disease Infection ...

  12. Staged abdominal re-operation for abdominal trauma.

    PubMed

    Taviloglu, Korhan

    2003-07-01

    To review the current developments in staged abdominal re-operation for abdominal trauma. To overview the steps of damage control laparotomy. The ever increasing importance of the resuscitation phase with current intensive care unit (ICU) support techniques should be emphasized. General surgeons should be familiar to staged abdominal re-operation for abdominal trauma and collaborate with ICU teams, interventional radiologists and several other specialties to overcome this entity.

  13. Ultrasonographic characteristics of the abdominal esophagus and cardia in dogs.

    PubMed

    Gory, Guillaume; Rault, Delphine N; Gatel, Laure; Dally, Claire; Belli, Patrick; Couturier, Laurent; Cauvin, Eddy

    2014-01-01

    Differential diagnoses for regurgitation and vomiting in dogs include diseases of the gastroesophageal junction. The purpose of this cross-sectional study was to describe ultrasonographic characteristics of the abdominal esophagus and gastric cardia in normal dogs and dogs with clinical disease involving this region. A total of 126 dogs with no clinical signs of gastrointestinal disease and six dogs with clinical diseases involving the gastroesophageal junction were included. For seven euthanized dogs, ultrasonographic features were also compared with gross pathology and histopathology. Cardial and abdominal esophageal wall thicknesses were measured ultrasonographically for all normal dogs and effects of weight, sex, age, and stomach filling were tested. Five layers could be identified in normal esophageal and cardial walls. The inner esophageal layer was echogenic, corresponding to the cornified mucosa and glandular portion of the submucosa. The cardia was characterized by a thick muscularis, and a transitional zone between echogenic esophageal and hypoechoic gastric mucosal layers. Mean (±SD) cardial wall thicknesses for normal dogs were 7.6 mm (±1.6), 9.7 mm (±1.8), 10.8 mm (±1.6), 13.3 mm (±2.5) for dogs in the <10 kg, 10-19.9 kg, 20-29.9 kg and ≥30 kg weight groups, respectively. Mean (±SD) esophageal wall thicknesses were: 4.1 mm (±0.6), 5.1 mm (±1.3), 5.6 mm (±1), and 6.4 mm (±1.1) for the same weight groups, respectively. Measurements of wall thickness were significantly correlated with dog weight group. Ultrasonography assisted diagnosis in all six clinically affected dogs. Findings supported the use of transabdominal ultrasonography as a diagnostic test for dogs with suspected gastroesophageal disease. © 2014 American College of Veterinary Radiology.

  14. PREFACE: Domain wall dynamics in nanostructures Domain wall dynamics in nanostructures

    NASA Astrophysics Data System (ADS)

    Marrows, C. H.; Meier, G.

    2012-01-01

    forms of ordered phases such as antiferromagnetism and ferroelectricity. We would like to thank the scientists from all over the world who happily agreed to contribute their latest results to this special issue, and the Journal of Physics: Condensed Matter staff for their help, patience and professionalism. In such a fast-moving field it is not possible to give a definitive account, and this special issue can be no more than a snapshot of the current state of knowledge regarding this topic. Nevertheless, we hope that this collection of papers is a useful resource for experienced workers in the field, forms a useful introduction to researchers early in their careers and inspires others in related areas of nanotechnology to enter into the study of domain dynamics in nanostructures. Domain wall dynamics in nanostructures contents Temperature estimation in a ferromagnetic Fe-Ni nanowire involving a current-driven domain wall motionA Yamaguchi, A Hirohata, T Ono and H Miyajima Magnetization reversal in magnetic nanostripes via Bloch wall formation M Zeisberger and R Mattheis Magnetic soft x-ray microscopy of the domain wall depinning process in permalloy magnetic nanowiresMi-Young Im, Lars Bocklage, Guido Meier and Peter Fischer Domain wall propagation in meso- and nanoscale ferroelectrics R G P McQuaid, M McMillen, L-W Chang, A Gruverman and J M Gregg Transverse and vortex domain wall structure in magnetic nanowires with uniaxial in-plane anisotropyM T Bryan, S Bance, J Dean, T Schrefl and D A Allwood The stochastic nature of the domain wall motion along high perpendicular anisotropy strips with surface roughness Eduardo Martinez Temperature-dependent dynamics of stochastic domain-wall depinning in nanowiresClemens Wuth, Peter Lendecke and Guido Meier Controlled pinning and depinning of domain walls in nanowires with perpendicular magnetic anisotropyTheo Gerhardt, André Drews and Guido Meier The interaction of transverse domain wallsBenjamin Krüger The increase of the

  15. Effect of thoracic epidural anesthesia combined with general anesthesia on segmental wall motion assessed by transesophageal echocardiography.

    PubMed

    Saada, M; Catoire, P; Bonnet, F; Delaunay, L; Gormezano, G; Macquin-Mavier, I; Brun, P

    1992-09-01

    Patients scheduled for vascular surgery are considered at risk for perioperative cardiac complications. Choice of anesthetic in such patients is guided by a desire not to adversely affect myocardial function. On the basis of data from laboratory studies, thoracic epidural anesthesia (TEA) has been advocated to prevent myocardial ischemia. The aim of this study was to assess whether TEA combined with general anesthesia has any effect on segmental wall motion (SWM) monitored by transesophageal echocardiography in these patients. Patients received alfentanil, midazolam, vecuronium, and 50% N2O in oxygen, and ventilation was controlled after orotracheal intubation; 12.5 mL of 2% lidocaine HCl was injected through an epidural catheter placed at T6-7 or T7-8. Hemodynamic measurements and transesophageal echocardiographic recordings were obtained before and 10, 20, 30, 40, and 60 min after lidocaine injection. Segmental wall motion was graded a posteriori by two independent experts on a predetermined scale (from 1 = normal to 5 = dyskinesia). A decrease greater than or equal to 2 grades was considered an SWM abnormality indicative of ischemia. Thoracic epidural anesthesia induced a decrease in systemic arterial blood pressure, heart rate, and cardiac index. The SWM score decreased slightly from 1.34 +/- 0.68 to 1.27 +/- 0.64 (mean +/- SD) (at 10 and 20 min, respectively) (P less than 0.05). Patients were a posteriori analyzed according to whether they had documented coronary artery disease or not. The SWM score before TEA was significantly higher in patients with documented coronary artery disease (1.51 +/- 0.88 vs 1.17 +/- 0.51, respectively; P less than 0.05) and did not change significantly after TEA.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Metabolic Syndrome is Associated With Higher Wall Motion Score and Larger Infarct Size After Acute Myocardial Infarction

    PubMed Central

    Hajsadeghi, Shokoufeh; Chitsazan, Mitra; Chitsazan, Mandana; Haghjoo, Majid; Babaali, Nima; Norouzzadeh, Zahra; Mohsenian, Maryam

    2015-01-01

    Background: Infarct size is an important surrogate end point for early and late mortality after acute myocardial infarction. Despite the high prevalence of metabolic syndrome in patients with atherosclerotic diseases, adequate data are still lacking regarding the extent of myocardial necrosis after acute myocardial infarction in these patients. Objectives: In the present study we aimed to compare myocardial infarction size in patients with metabolic syndrome to those without metabolic syndrome using peak CK-MB and cardiac troponin I (cTnI) at 72 hours after the onset of symptoms. Patients and Methods: One-hundred patients with metabolic syndrome (group I) and 100 control subjects without metabolic syndrome (group II) who experienced acute myocardial infarction were included in the study. Diagnosis of metabolic syndrome was based on the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) guidelines published in 2001. Myocardial infarction size was compared between the two groups of patients using peak CK-MB and cTnI level in 72 hours after the onset of symptoms. Results: Peak CK-MB and cTnI in 72 hours were found to be significantly higher in patients with metabolic syndrome compared with control subjects (both P < 0.001). Patients with metabolic syndrome also had markedly higher wall motion abnormality at 72 hours after the onset of symptoms as assessed by echocardiographically-derived Wall Motion Score Index (WMSI) (P < 0.001). Moreover, statistically significant relationships were found between WMSI and peak CK-MB and also cTnI at 72 hours (Spearman's rho = 0.56, P < 0.001 and Spearman's rho = 0.5, P < 0.001; respectively). However, association between WMSI and left ventricular ejection fraction was insignificant (Spearman's rho = -0.05, P = 0.46). Conclusions: We showed that patients with metabolic syndrome have larger infarct size compared to control subjects. PMID:25789257

  17. Domain wall kinetics of lithium niobate single crystals near the hexagonal corner

    NASA Astrophysics Data System (ADS)

    Choi, Ju Won; Ko, Do-Kyeong; Yu, Nan Ei; Kitamura, Kenji; Ro, Jung Hoon

    2015-03-01

    A mesospheric approach based on a simple microscopic 2D Ising model in a hexagonal lattice plane is proposed to explain macroscopic "asymmetric in-out domain wall motion" observation in the (0001) plane of MgO-doped stoichiometric lithium niobate. Under application of an electric field that was higher than the conventional coercive field (Ec) to the ferroelectric crystal, a natural hexagonal domain was obtained with walls that were parallel to the Y-axis of the crystal. When a fraction of the coercive field of around 0.1Ec is applied in the reverse direction, this hexagonal domain is shrunk (moved inward) from the corner site into a shape with a corner angle of around 150° and 15° wall slopes to the Y-axis. A flipped electric field of 0.15Ec is then applied to recover the natural hexagonal shape, and the 150° corner shape changes into a flat wall with 30° slope (moved outward). The differences in corner domain shapes between inward and outward domain motion were analyzed theoretically in terms of corner and wall site energies, which are described using the domain corner angle and wall slope with respect to the crystal Y-axis, respectively. In the inward domain wall motion case, the energy levels of the evolving 150° domain corner and 15° slope walls are most competitive, and could co-exist. In the outward case, the energy levels of corners with angles >180° are highly stable when compared with the possible domain walls; only a flat wall with 30° slope to the Y-axis is possible during outward motion.

  18. SU-F-T-121: Abdominal Compression Effectively Reduces the Interplay Effect and Enables Pencil Beam Scanning Proton Therapy of Liver Tumors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Souris, K; University of Pennsylvania, Philadelphia, PA; Glick, A

    Purpose: To study if abdominal compression can reduce breathing motion and mitigate interplay effect in pencil beam scanning proton therapy (PBSPT) treatment of liver tumors in order to better spare healthy liver volumes compared with photon therapy. Methods: Ten patients, six having large tumors initially treated with IMRT and four having small tumors treated with SBRT, were replanned for PBSPT. ITV and beam-specific PTVs based on 4D-CT were used to ensure target coverage in PBSPT. The use of an abdominal compression belt and volumetric repainting was investigated to mitigate the interplay effect between breathing motion and PBSPT dynamic delivery. Anmore » in-house Matlab script has been developed to simulate this interplay effect. The dose is computed on each phase individually by sorting all spots according to their simulated delivery timing. The final dose distribution is then obtained by accumulating all dose maps to a reference phase. Results: For equivalent target coverage PBSPT reduced average healthy liver dose by 9.5% of the prescription dose compared with IMRT/SBRT. Abdominal compression of 113.2±42.2 mmHg was effective for all 10 patients and reduced average motion by 2.25 mm. As a result, the average ITV volume decreased from 128.2% to 123.1% of CTV volume. Similarly, the average beam-specific PTV volume decreased from 193.2% to 183.3%. For 8 of the 10 patients, the average motion was reduced below 5 mm, and up to 3 repainting were sufficient to mitigate interplay. For the other two patients with larger residual motion, 4–5 repainting were needed. Conclusion: We recommend evaluation of the 4DCT motion histogram following simulation and the interplay effect following treatment planning in order to personalize the use of compression and volumetric repainting for each patient. Abdominal compression enables safe and more effective PBS treatment of liver tumors by reduction of motion and interplay effect. Kevin Souris is supported by IBA and Televie

  19. Abdominal actinomycosis masquerading as an omental tumor in a 12-year-old female.

    PubMed

    Hirayama, Yutaka; Iinuma, Yasushi; Hashizume, Naoki; Yoshida, Motomu; Iida, Hisataka; Shibuya, Hiroyuki; Naito, Shinichi; Nitta, Koju

    2013-02-01

    We herein report a case of abdominal actinomycosis in a 12-year-old girl in whom an omental primary tumor was suspected before surgery. The patient began to experience intermittent lower left abdominal pain. Abdominal computed tomography (CT) scans were inconclusive at this time, but 6 months later, CT and magnetic resonance imaging (MRI) examinations showed a 7-cm, tumor-like lesion in the left abdominal cavity; malignancy could not be ruled out. The tumor, which originated in the omentum and adhered strongly to the left abdominal wall, was resected along with approximately 90 % of the omentum, the peritoneum in contact with the mass, and the posterior layer of the rectus abdominal sheath, under suspicion of a malignant tumor. However, omental actinomycosis was the final pathological diagnosis. The patient's antibiotic treatment was changed to a penicillin-series oral antibiotic to prevent recurrence of the actinomycosis. The patient was discharged from our hospital 16 days after the first surgery, but she developed three episodes of ileus; the first two required surgery. The patient has had no further recurrences of actinomycosis or postoperative ileus 20 months after discharge.

  20. The impact of a massive transfusion protocol (1:1:1) on major hepatic injuries: does it increase abdominal wall closure rates?

    PubMed

    Ball, Chad G; Dente, Christopher J; Shaz, Beth; Wyrzykowski, Amy D; Nicholas, Jeffrey M; Kirkpatrick, Andrew W; Feliciano, David V

    2013-10-01

    Massive transfusion protocols (MTPs) using high plasma and platelet ratios for exsanguinating trauma patients are increasingly popular. Major liver injuries often require massive resuscitations and immediate hemorrhage control. Current published literature describes outcomes among patients with mixed patterns of injury. We sought to identify the effects of an MTP on patients with major liver trauma. Patients with grade 3, 4 or 5 liver injuries who required a massive blood component transfusion were analyzed. We compared patients with high plasma:red blood cell:platelet ratio (1:1:1) transfusions (2007-2009) with patients injured before the creation of an institutional MTP (2005-2007). Among 60 patients with major hepatic injuries, 35 (58%) underwent resuscitation after the implementation of an MTP. Patient and injury characteristics were similar between cohorts. Implementation of the MTP significantly improved plasma: red blood cell:platelet ratios and decreased crystalloid fluid resuscitation (p = 0.026). Rapid improvement in early acidosis and coagulopathy was superior with an MTP (p = 0.009). More patients in the MTP group also underwent primary abdominal fascial closure during their hospital stay (p = 0.021). This was most evident with grade 4 injuries (89% vs. 14%). The mean time to fascial closure was 4.2 days. The overall survival rate for all major liver injuries was not affected by an MTP (p = 0.61). The implementation of a formal MTP using high plasma and platelet ratios resulted in a substantial increase in abdominal wall approximation. This occurred concurrently to a decrease in the delivered volume of crystalloid fluid.

  1. Vestibular system and neural correlates of motion sickness

    NASA Technical Reports Server (NTRS)

    Miller, Alan D.

    1986-01-01

    Initial studies re-examine the role of certain central nervous system structures in the production of vestibular-induced vomiting and vomiting in general. All experiments were conducted using cats. Since these studies demonstrated that the essential role of various central structures in vestibular-induced vomiting is only poorly understood, efforts were re-directed to study the control of the effector muscles (diaphragm and abdominal muscles) that produce the pressure changes responsible for vomiting, with the goal of determining how this control mechanism is engaged during motion sickness. Experiments were conducted to localize the motoneurons that innervate the individual abdominal muscles and the portion of the diaphragm that surrounds the esophagus. A central question regarding respiratory muscle control during vomiting is whether these muscles are activated via the same brain stem pre-motor neurons that provide descending respiratory drive and/or by other descending input(s). In other experiments, the use of a combination of pitch and roll motions to produce motion sickness in unrestrained cats was evaluated. This stimulus combination can produce vomiting in only the most susceptible cats and is thus not as provacative a stimulus for cats as vertical linear acceleration.

  2. Rotational Motion of Axisymmetric Marangoni Swimmers

    NASA Astrophysics Data System (ADS)

    Rothstein, Jonathan; Uvanovic, Nick

    2017-11-01

    A series of experiments will be presented investigating the motion of millimeter-sized particles on the surface of water. The particles were partially coated with ethanol and carefully placed on a water interface in a series of Petri dishes with different diameters. High speed particle motion was driven by strong surface tension gradients as the ethanol slowly diffuses from the particles into the water resulting in a Marangoni flow. The velocity and acceleration of the particles where measured. In addition to straight line motion, the presence of the bounding walls of the circular Petri dish was found to induce an asymmetric, rotational motion of the axisymmetric Marangoni swimmers. The rotation rate and radius of curvature was found to be a function of the size of the Petri dish and the curvature of the air-water interface near the edge of the dish. For large Petri dishes or small particles, rotation motion was observed far from the bounding walls. In these cases, the symmetry break appears to be the result of the onset of votex shedding. Finally, multiple spherical particles were observed to undergo assembly driven by capillary forces followed by explosive disassembly.

  3. SU-F-BRB-01: How Effective Is Abdominal Compression at Reducing Lung Motion? An Analysis Using Deformable Image Registration Within Different Sub-Regions of the Lung

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paradiso, D; Pearce, A; Leszczynski, K

    2015-06-15

    Purpose: To investigate the effectiveness of employing abdominal compression (AC) in reducing motion for the target region and sub-regions of the lung as part of the planning process for radiation therapy. Methods: Fourteen patients with early lung cancer were scanned with 4DCT and it was determined that target motion exceeded our institutional limit of > 8 mm motion and received a repeat 4DCT with AC. For each 4DCT, deformable image registration (DIR) was used to map the max inhale to the max exhale phase to determine the deformation vector fields (DVF). DIR was performed with Morphons and Demons algorithms. Themore » mean DVF was used to represent that sub-region for each patient. The magnitudes of the mean DVF were quantified for the target and 12 sub-regions in the AP, LR SI directions. The sub-regions were contoured on each lung as (add prefix R or L for lung): Upper-Anterior (UA), Upper-Posterior (UP), Mid-Anterior (MA), Mid-Posterior (MP), Lower-Anterior (LA) and Lower-Posterior (LP). Results: The min/max SI motion for the target on the uncompressed 4DCT was 8mm/24.5 mm. The magnitude of decrease in SI was greatest in the RLP region (3.7±4.0mm) followed by target region (3.3±2.2mm) and finally the LLP region (3.0±3.5mm). The magnitude of decrease in 3D vector followed the same trend; RLP (3.5±2.2mm) then GTV (3.5±2.6mm) then LLP (2.7±3.8mm). 79% of the cases had a SI decrease of >12.5%, 43% had a SI decrease of >25% and 21% had a SI decrease of >50% as compared to the motion on the uncompressed 4DCT. Conclusion: AC is useful in reducing motion with the largest decreases observed in the lower posterior regions of the lungs. However, it should be noted that AC will not greatly decrease motion for all cases as 21% of cases did not reduce SI motion more than 12.5% of initial motion.« less

  4. Translational Response of Toe-Restrained Retaining Walls to Earthquake Ground Motions Using CorpsWallSlip (CWSlip)

    DTIC Science & Technology

    2007-06-01

    corresponding software developed for the translational response of rock- founded retaining walls buttressed at their toe by a reinforced concrete slab...by a Reinforced Concrete Slab ...........................................................................................................32 2.1...2.5 New translational analysis model of a wall retaining a partially submerged backfill and buttressed by a reinforced concrete slab

  5. Fluid, solid and fluid-structure interaction simulations on patient-based abdominal aortic aneurysm models.

    PubMed

    Kelly, Sinead; O'Rourke, Malachy

    2012-04-01

    This article describes the use of fluid, solid and fluid-structure interaction simulations on three patient-based abdominal aortic aneurysm geometries. All simulations were carried out using OpenFOAM, which uses the finite volume method to solve both fluid and solid equations. Initially a fluid-only simulation was carried out on a single patient-based geometry and results from this simulation were compared with experimental results. There was good qualitative and quantitative agreement between the experimental and numerical results, suggesting that OpenFOAM is capable of predicting the main features of unsteady flow through a complex patient-based abdominal aortic aneurysm geometry. The intraluminal thrombus and arterial wall were then included, and solid stress and fluid-structure interaction simulations were performed on this, and two other patient-based abdominal aortic aneurysm geometries. It was found that the solid stress simulations resulted in an under-estimation of the maximum stress by up to 5.9% when compared with the fluid-structure interaction simulations. In the fluid-structure interaction simulations, flow induced pressure within the aneurysm was found to be up to 4.8% higher than the value of peak systolic pressure imposed in the solid stress simulations, which is likely to be the cause of the variation in the stress results. In comparing the results from the initial fluid-only simulation with results from the fluid-structure interaction simulation on the same patient, it was found that wall shear stress values varied by up to 35% between the two simulation methods. It was concluded that solid stress simulations are adequate to predict the maximum stress in an aneurysm wall, while fluid-structure interaction simulations should be performed if accurate prediction of the fluid wall shear stress is necessary. Therefore, the decision to perform fluid-structure interaction simulations should be based on the particular variables of interest in a given

  6. Histology and Biaxial Mechanical Behavior of Abdominal Aortic Aneurysm Tissue Samples.

    PubMed

    Pancheri, Francesco Q; Peattie, Robert A; Reddy, Nithin D; Ahamed, Touhid; Lin, Wenjian; Ouellette, Timothy D; Iafrati, Mark D; Luis Dorfmann, A

    2017-03-01

    Abdominal aortic aneurysms (AAAs) represent permanent, localized dilations of the abdominal aorta that can be life-threatening if progressing to rupture. Evaluation of risk of rupture depends on understanding the mechanical behavior of patient AAA walls. In this project, a series of patient AAA wall tissue samples have been evaluated through a combined anamnestic, mechanical, and histopathologic approach. Mechanical properties of the samples have been characterized using a novel, strain-controlled, planar biaxial testing protocol emulating the in vivo deformation of the aorta. Histologically, the tissue ultrastructure was highly disrupted. All samples showed pronounced mechanical stiffening with stretch and were notably anisotropic, with greater stiffness in the circumferential than the axial direction. However, there were significant intrapatient variations in wall stiffness and stress. In biaxial tests in which the longitudinal stretch was held constant at 1.1 as the circumferential stretch was extended to 1.1, the maximum average circumferential stress was 330 ± 70 kPa, while the maximum average axial stress was 190 ± 30 kPa. A constitutive model considering the wall as anisotropic with two preferred directions fit the measured data well. No statistically significant differences in tissue mechanical properties were found based on patient gender, age, maximum bulge diameter, height, weight, body mass index, or smoking history. Although a larger patient cohort is merited to confirm these conclusions, the project provides new insight into the relationships between patient natural history, histopathology, and mechanical behavior that may be useful in the development of accurate methods for rupture risk evaluation.

  7. Broadband boundary effects on Brownian motion.

    PubMed

    Mo, Jianyong; Simha, Akarsh; Raizen, Mark G

    2015-12-01

    Brownian motion of particles in confined fluids is important for many applications, yet the effects of the boundary over a wide range of time scales are still not well understood. We report high-bandwidth, comprehensive measurements of Brownian motion of an optically trapped micrometer-sized silica sphere in water near an approximately flat wall. At short distances we observe anisotropic Brownian motion with respect to the wall. We find that surface confinement not only occurs in the long time scale diffusive regime but also in the short time scale ballistic regime, and the velocity autocorrelation function of the Brownian particle decays faster than that of a particle in bulk fluid. Furthermore, at low frequencies the thermal force loses its color due to the reflected flow from the no-slip boundary. The power spectrum of the thermal force on the particle near a no-slip boundary becomes flat at low frequencies. This detailed understanding of boundary effects on Brownian motion opens a door to developing a 3D microscope using particles as remote sensors.

  8. The Economic Impact of Closed-Incision Negative-Pressure Therapy in High-Risk Abdominal Incisions: A Cost-Utility Analysis.

    PubMed

    Chopra, Karan; Gowda, Arvind U; Morrow, Chris; Holton, Luther; Singh, Devinder P

    2016-04-01

    Complex abdominal wall reconstruction is beset by postoperative complications. A recent meta-analysis comparing the use of closed-incision negative-pressure therapy to standard dressings found a statistically significant reduction in surgical-site infection. The use of closed-incision negative-pressure therapy is gaining acceptance in this population; however, the economic impact of this innovative dressing remains unknown. In this study, a cost-utility analysis was performed assessing closed-incision negative-pressure therapy and standard dressings following closure of abdominal incisions in high-risk patients. Cost-utility methodology involved reviewing literature related to closed-incision negative-pressure therapy in abdominal wall surgery, obtaining utility estimates to calculate quality-adjusted life-year scores for successful surgery and surgery complicated by surgical-site infection, summing costs using Medicare Current Procedural Terminology codes, and creating a decision tree illuminating the most cost-effective dressing strategy. One-way sensitivity analysis was performed to assess the robustness of the results. The aforementioned meta-analysis comparing closed-incision negative-pressure therapy to standard dressings included a subset of five studies assessing abdominal wall surgery in 829 patients (260 closed-incision negative-pressure therapy and 569 standard dressings). Decision tree analysis revealed an estimated savings of $1546.52 and a gain of 0.0024 quality-adjusted life-year with closed-incision negative-pressure therapy compared with standard dressings; therefore, closed-incision negative-pressure therapy is a dominant treatment strategy. One-way sensitivity analysis revealed that closed-incision negative-pressure therapy is a cost-effective option when the surgical-site infection rate is greater than 16.39 percent. The use of closed-incision negative-pressure therapy is cost-saving following closure of abdominal incisions in high-risk patients.

  9. A numerical framework for studying the biomechanical behavior of abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Jalalahmadi, Golnaz; Linte, Cristian; Helguera, María.

    2017-03-01

    Abdominal aortic aneurysm (AAA) is known as a leading cause of death in the United States. AAA is an abnormal dilation of the aorta, which usually occurs below the renal arteries and causes an expansion at least 1.5 times its normal diameter. It has been shown that biomechanical parameters of the aortic tissue coupled with a set of specific geometric parameters characterizing the vessel expansion, affect the risk of aneurysm rupture. Here, we developed a numerical framework that incorporates both biomechanical and geometrical factors to study the behavior of abdominal aortic aneurysm. Our workflow enables the extraction of the aneurysm geometry from both clinical quality, as well as low-resolution MR images. We used a two-parameter, hyper-elastic, isotropic, incompressible material to model the vessel tissue. Our numerical model was tested using both synthetic and mouse data and we evaluated the effects of the geometrical and biomechanical properties on the developed peak wall stress. In addition, we performed several parameter sensitivity studies to investigate the effect of different factors affecting the AAA and its behavior and rupture. Lastly, relationships between different geometrical and biomechanical parameters and peak wall stress were determined. These studies help us better understand vessel tissue response to various loading, geometry and biomechanics conditions, and we plan to further correlate these findings with the pathophysiological conditions from a patient population diagnosed with abdominal aortic aneurysms.

  10. CFD modelling of abdominal aortic aneurysm on hemodynamic loads using a realistic geometry with CT.

    PubMed

    Soudah, Eduardo; Ng, E Y K; Loong, T H; Bordone, Maurizio; Pua, Uei; Narayanan, Sriram

    2013-01-01

    The objective of this study is to find a correlation between the abdominal aortic aneurysm (AAA) geometric parameters, wall stress shear (WSS), abdominal flow patterns, intraluminal thrombus (ILT), and AAA arterial wall rupture using computational fluid dynamics (CFD). Real AAA 3D models were created by three-dimensional (3D) reconstruction of in vivo acquired computed tomography (CT) images from 5 patients. Based on 3D AAA models, high quality volume meshes were created using an optimal tetrahedral aspect ratio for the whole domain. In order to quantify the WSS and the recirculation inside the AAA, a 3D CFD using finite elements analysis was used. The CFD computation was performed assuming that the arterial wall is rigid and the blood is considered a homogeneous Newtonian fluid with a density of 1050 kg/m(3) and a kinematic viscosity of 4 × 10(-3) Pa·s. Parallelization procedures were used in order to increase the performance of the CFD calculations. A relation between AAA geometric parameters (asymmetry index ( β ), saccular index ( γ ), deformation diameter ratio ( χ ), and tortuosity index ( ε )) and hemodynamic loads was observed, and it could be used as a potential predictor of AAA arterial wall rupture and potential ILT formation.

  11. Hospital readmission following open, single-stage, elective abdominal wall reconstructions using acellular dermal matrix affects long-term hernia recurrence rate.

    PubMed

    Giordano, Salvatore A; Garvey, Patrick B; Baumann, Donald P; Liu, Jun; Butler, Charles E

    2018-02-05

    We evaluated the incidence of and the risk factors for readmission in patients who underwent abdominal wall reconstruction (AWR) using acellular dermal matrix (ADM) and assess whether readmission affects AWR long-term outcomes. A retrospective, single-center study of patients underwent AWR with ADM was conducted. The primary outcome was the incidence of unplanned readmission within 30 days after the initial discharge post-AWR. Secondary outcomes were surgical site occurrence (SSO) and hernia recurrence at follow-up. Of 452 patients (mean age, 59 years; mean follow-up, 35 months), 29 (6.4%) were readmitted within 30 days. Most readmissions were due to SSO (44.8%) or wound infections (12.8%). The hernia recurrence rate was significantly higher in readmitted patients (17.2% vs 9.9%; P = 0.044). Wider defects, prolonged operative time, and coronary artery disease were independent predictors of readmission. Readmission is associated with hernia recurrence on long-term follow-up. SSO is the most common cause for readmission. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Laparoscopic cholecystectomy using abdominal wall retraction. Hemodynamics and gas exchange, a comparison with conventional pneumoperitoneum.

    PubMed

    Meijer, D W; Rademaker, B P; Schlooz, S; Bemelman, W A; de Wit, L T; Bannenberg, J J; Stijnen, T; Gouma, D F

    1997-06-01

    Disadvantages related to CO2 pneumoperitoneum have led to development of the abdominal wall retractor (AWR), a device designed to facilitate laparoscopic surgery without conventional pneumoperitoneum (15 mmHg CO2). We investigated the effects of the AWR on hemodynamics and gas exchange in humans. We also investigated whether the use of an AWR imposed extra technical difficulties for the surgeon. A pilot study revealed that cholecystectomy without low-pressure pneumoperitoneum was technically impossible. A prospective randomized controlled trial: Twenty patients undergoing laparoscopic cholecystectomy were randomly allocated into group 1: AWR with low-pressure pneumoperitoneum (5 mmHg), or group 2: conventional pneumoperitoneum (15 mmHg). Surgery using the AWR lasted longer, 72 +/- 16 min (mean +/- SD) vs 50 +/- 18 min compared with standard laparoscopic cholecystectomy. There were no differences between the groups with respect to hemodynamic parameters, although a small reduction of the cardiac output was observed using conventional pneumoperitoneum (from 3.9 +/- 0.7 to 3. 2 +/- 1.1 l/min) and an increase during AWR (from 4.2 +/- 0.9 to 5.2 +/- 1.5 l/min). Peak inspiratory pressures were significantly higher during conventional pneumoperitoneum compared to AWR. A slight decrease in pH accompanied by an increase in CO2 developed during pneumoperitoneum and during the use of the AWR. In both groups arterial PO2 decreased. The results indicate that the view was impaired during use of the AWR and therefore its use was difficult and time-consuming. Possible advantages of this devices' effects on hemodynamics and ventilatory parameters could not be confirmed in this study.

  13. Corrections to the thin wall approximation in general relativity

    NASA Technical Reports Server (NTRS)

    Garfinkle, David; Gregory, Ruth

    1989-01-01

    The question is considered whether the thin wall formalism of Israel applies to the gravitating domain walls of a lambda phi(exp 4) theory. The coupled Einstein-scalar equations that describe the thick gravitating wall are expanded in powers of the thickness of the wall. The solutions of the zeroth order equations reproduce the results of the usual Israel thin wall approximation for domain walls. The solutions of the first order equations provide corrections to the expressions for the stress-energy of the wall and to the Israel thin wall equations. The modified thin wall equations are then used to treat the motion of spherical and planar domain walls.

  14. Transversus abdominal plane (TAP) block for postoperative pain management: a review.

    PubMed

    Jakobsson, Jan; Wickerts, Liselott; Forsberg, Sune; Ledin, Gustaf

    2015-01-01

    Transversus abdominal plane (TAP) block has a long history and there is currently extensive clinical experience around TAP blocks. The aim of this review is to provide a summary of the present evidence on the effects of TAP block and to provide suggestions for further studies. There are several approaches to performing abdominal wall blocks, with the rapid implementation of ultrasound-guided technique facilitating a major difference in TAP block performance. During surgery, an abdominal wall block may also be applied by the surgeon from inside the abdominal cavity. Today, there are more than 11 meta-analyses providing a compiled evidence base around the effects of TAP block. These analyses include different procedures, different techniques of TAP block administration and, importantly, they compare the TAP block with a variety of alternative analgesic regimes. The effects of TAP block during laparoscopic cholecystectomy seem to be equivalent to local infiltration analgesia and also seem to be beneficial during laparoscopic colon resection. The effects of TAP are more pronounced when it is provided prior to surgery and these effects are local anaesthesia dose-dependent. TAP block seems an interesting alternative in patients with, for example, severe obesity where epidural or spinal anaesthesia/analgesia is technically difficult and/or poses a risk. There is an obvious need for further high-quality studies comparing TAP block prior to surgery with local infiltration analgesia, single-shot spinal analgesia, and epidural analgesia. These studies should be procedure-specific and the effects should be evaluated, both regarding short-term pain and analgesic requirement and also including the effects on postoperative nausea and vomiting, recovery of bowel function, ambulation, discharge, and protracted recovery outcomes (assessed by e.g., postoperative quality of recovery scale).

  15. Negative pressure wound therapy with instillation, a cost-effective treatment for abdominal mesh exposure.

    PubMed

    Deleyto, E; García-Ruano, A; González-López, J R

    2018-04-01

    Negative pressure wound therapy with instillation (NPWTi) has been proved to be a safe and effective treatment option for abdominal wall wound dehiscence with mesh exposure. Our aim in this study is to examine whether it is also cost-effective. We performed a retrospective cohort study with 45 patients treated for postoperative abdominal wall wound dehiscence and exposed mesh: 34 were treated with conventional wound therapy (CWT) and 11 with NPWTi. We carried out a cost analysis for each treatment group using the Diagnosis-related group (DRG) system and a second evaluation using the calculated costs "per hospital stay". The differences between NPWTi and CWT were calculated with both evaluation systems. Comparative analysis was performed using the Mann-Whitney U test. Mean costs using the DRG estimation were 29,613.71€ for the CWT group and 15,093.37€ for the NPWTi group, and according to the calculated expenses "per hospital stay", 17,322.88€ for the CWT group and 15,284.22€ for the NPWTi group. NPWTi showed a reduction in the total expense of treatment, related to a reduction in episodes of hospitalization and number of surgeries required to achieve wound closure. However, differences were not statistically significant in our sample. NPWTi proves to be an efficient treatment option for abdominal wall wound dehiscence with mesh exposure, compared to CWT. More trials aimed to optimize treatment protocols will lead to an additional increase in NPWTi efficiency. In addition, to generalize our results, further studies with larger samples would be necessary.

  16. Sensing of minute airflow motions near walls using pappus-type nature-inspired sensors

    PubMed Central

    Mikulich, Vladimir

    2017-01-01

    This work describes the development and use of pappus-like structures as sensitive sensors to detect minute air-flow motions. We made such sensors from pappi taken from nature-grown seed, whose filiform hairs’ length-scale is suitable for the study of large-scale turbulent convection flows. The stem with the pappus on top is fixated on an elastic membrane on the wall and tilts under wind-load proportional to the velocity magnitude in direction of the wind, similar as the biological sensory hairs found in spiders, however herein the sensory hair has multiple filiform protrusions at the tip. As the sensor response is proportional to the drag on the tip and a low mass ensures a larger bandwidth, lightweight pappus structures similar as those found in nature with documented large drag are useful to improve the response of artificial sensors. The pappus of a Dandelion represents such a structure which has evolved to maximize wind-driven dispersion, therefore it is used herein as the head of our sensor. Because of its multiple hairs arranged radially around the stem it generates uniform drag for all wind directions. While still being permeable to the flow, the hundreds of individual hairs on the tip of the sensor head maximize the drag and minimize influence of pressure gradients or shear-induced lift forces on the sensor response as they occur in non-permeable protrusions. In addition, the flow disturbance by the sensor itself is limited. The optical recording of the head-motion allows continuously remote-distance monitoring of the flow fluctuations in direction and magnitude. Application is shown for the measurement of a reference flow under isothermal conditions to detect the early occurrence of instabilities. PMID:28658272

  17. Fluid-structure interaction in abdominal aortic aneurysms: Structural and geometrical considerations

    NASA Astrophysics Data System (ADS)

    Mesri, Yaser; Niazmand, Hamid; Deyranlou, Amin; Sadeghi, Mahmood Reza

    2015-08-01

    Rupture of the abdominal aortic aneurysm (AAA) is the result of the relatively complex interaction of blood hemodynamics and material behavior of arterial walls. In the present study, the cumulative effects of physiological parameters such as the directional growth, arterial wall properties (isotropy and anisotropy), iliac bifurcation and arterial wall thickness on prediction of wall stress in fully coupled fluid-structure interaction (FSI) analysis of five idealized AAA models have been investigated. In particular, the numerical model considers the heterogeneity of arterial wall and the iliac bifurcation, which allows the study of the geometric asymmetry due to the growth of the aneurysm into different directions. Results demonstrate that the blood pulsatile nature is responsible for emerging a time-dependent recirculation zone inside the aneurysm, which directly affects the stress distribution in aneurismal wall. Therefore, aneurysm deviation from the arterial axis, especially, in the lateral direction increases the wall stress in a relatively nonlinear fashion. Among the models analyzed in this investigation, the anisotropic material model that considers the wall thickness variations, greatly affects the wall stress values, while the stress distributions are less affected as compared to the uniform wall thickness models. In this regard, it is confirmed that wall stress predictions are more influenced by the appropriate structural model than the geometrical considerations such as the level of asymmetry and its curvature, growth direction and its extent.

  18. Simultaneous Prosthetic Mesh Abdominal Wall Reconstruction with Abdominoplasty for Ventral Hernia and Severe Rectus Diastasis Repairs

    PubMed Central

    Cheesborough, Jennifer E.

    2015-01-01

    Background: Standard abdominoplasty rectus plication techniques may not suffice for severe cases of rectus diastasis. In the authors’ experience, prosthetic mesh facilitates the repair of severe rectus diastasis with or without concomitant ventral hernias. Methods: A retrospective review of all abdominal wall surgery patients treated in the past 8 years by the senior author (G.A.D.) was performed. Patients with abdominoplasty and either rectus diastasis repair with mesh or a combined ventral hernia repair were analyzed. Results: Thirty-two patients, 29 women and three men, underwent mesh-reinforced midline repair with horizontal or vertical abdominoplasty. Patient characteristics included the following: mean age, 53 years; mean body mass index, 26 kg/m2; average width of diastasis or hernia, 6.7 cm; and average surgery time, 151 minutes. There were no surgical-site infections and two surgical-site occurrences—two seromas treated with drainage in the office. After an average of 471 days’ follow-up, none of the patients had recurrence of a bulge or a hernia. Conclusions: For patients with significant rectus diastasis, with or without concomitant hernias, the described mesh repair is both safe and durable. Although this operation requires additional dissection and placement of prosthetic mesh in the retrorectus plane, it may be safely combined with standard horizontal or vertical abdominoplasty skin excision techniques to provide an aesthetically pleasing overall result. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV. PMID:25539311

  19. [Abdominal trauma].

    PubMed

    Sido, B; Grenacher, L; Friess, H; Büchler, M W

    2005-09-01

    Blunt abdominal trauma is much more frequent than penetrating abdominal trauma in Europe. As a consequence of improved quality of computed tomography, even complex liver injuries are increasingly being treated conservatively. However, missed hollow viscus injuries still remain a problem, as they considerably increase mortality in multiply injured patients. Laparoscopy decreases the rate of unnecessary laparotomies in perforating abdominal trauma and helps to diagnose injuries of solid organs and the diaphragm. However, the sensitivity in detecting hollow viscus injuries is low and the role of laparoscopy in blunt abdominal injury has not been defined. If intra-abdominal bleeding is difficult to control in hemodynamically unstable patients, damage control surgery with packing of the liver, total splenectomy, and provisional closure of hollow viscus injuries is of importance. Definitive surgical treatment follows hemodynamic stabilization and restoration of hemostasis. Injuries of the duodenum and pancreas after blunt abdominal trauma are often associated with other intra-abdominal injuries and the treatment depends on their location and severity.

  20. Stereotactic body radiation therapy for abdominal oligometastases: a biological and clinical review

    PubMed Central

    2012-01-01

    Advances in imaging and biological targeting have led to the development of stereotactic body radiation therapy (SBRT) as an alternative treatment of extracranial oligometastases. New radiobiological concepts, such as ceramide-induced endothelial apoptosis after hypofractionated high-dose SBRT, and the identification of patients with oligometastatic disease by microRNA expression may yet lead to further developments. Key factors in SBRT are delivery of a high dose per fraction, proper patient positioning, target localisation, and management of breathing–related motion. Our review addresses the radiation doses and schedules used to treat liver, abdominal lymph node (LN) and adrenal gland oligometastases and treatment outcomes. Reported local control (LC) rates for liver and abdominal LN oligometastases are high (median 2-year actuarial LC: 61 -100% for liver oligometastases; 4-year actuarial LC: 68% in a study of abdominal LN oligometastases). Early toxicity is low-to-moderate; late adverse effects are rare. SBRT of adrenal gland oligometastases shows promising results in the case of isolated lesions. In conclusion, properly conducted SBRT procedures are a safe and effective treatment option for abdominal oligometastases. PMID:22852764

  1. Comparison of lateral abdominal muscle thickness between weightlifters and matched controls.

    PubMed

    Sitilertpisan, Patraporn; Pirunsan, Ubon; Puangmali, Aatit; Ratanapinunchai, Jonjin; Kiatwattanacharoen, Suchart; Neamin, Hudsaleark; Laskin, James J

    2011-11-01

    To compare lateral abdominal muscle thickness between weightlifters and matched controls. A case control study design. University laboratory. 16 female Thai national weightlifters and 16 matched controls participated in this study. Ultrasound imaging with a 12-MHz linear array was used to measure the resting thickness of transversus abdominis (TrA), internal oblique (IO) and total thickness (Total) of lateral abdominal muscle (LAM) on the right side of abdominal wall. The absolute muscle thickness and the relative contribution of each muscle to the total thickness were determined. Weightlifters had significantly thicker absolute TrA and IO muscles than matched controls (p < 0.01). Further, the relative thickness of the IO was significantly greater in weightlifters than matched controls (p < 0.05). The findings of this study suggest that routine Olympic style weight training among female weightlifters appears to result in preferential hypertrophy or adaptation of the IO muscle. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Motion tracing system for ultrasound guided HIFU

    NASA Astrophysics Data System (ADS)

    Xiao, Xu; Jiang, Tingyi; Corner, George; Huang, Zhihong

    2017-03-01

    One main limitation in HIFU treatment is the abdominal movement in liver and kidney caused by respiration. The study has set up a tracking model which mainly compromises of a target carrying box and a motion driving balloon. A real-time B-mode ultrasound guidance method suitable for tracking of the abdominal organ motion in 2D was established and tested. For the setup, the phantoms mimicking moving organs are carefully prepared with agar surrounding round-shaped egg-white as the target of focused ultrasound ablation. Physiological phantoms and animal tissues are driven moving reciprocally along the main axial direction of the ultrasound image probe with slightly motion perpendicular to the axial direction. The moving speed and range could be adjusted by controlling the inflation and deflation speed and amount of the balloon driven by a medical ventilator. A 6-DOF robotic arm was used to position the focused ultrasound transducer. The overall system was trying to estimate to simulate the actual movement caused by human respiration. HIFU ablation experiments using phantoms and animal organs were conducted to test the tracking effect. Ultrasound strain elastography was used to post estimate the efficiency of the tracking algorithms and system. In moving state, the axial size of the lesion (perpendicular to the movement direction) are averagely 4mm, which is one third larger than the lesion got when the target was not moving. This presents the possibility of developing a low-cost real-time method of tracking organ motion during HIFU treatment in liver or kidney.

  3. RLC model of visco-elastic properties of the chest wall

    NASA Astrophysics Data System (ADS)

    Aliverti, Andrea; Ferrigno, Giancarlo

    1996-04-01

    The quantification of the visco-elastic properties (resistance (R), inertia (L) and compliance (C)) of the different chest wall compartments (pulmonary rib cage,diaphragmatic rib cage and abdomen) is important to study the status of the passive components of the respiratory system, particularly in selected pathologies. Applying the viscoelastic-electrical analogy to the chest wall, we used an identification method in order to estimate the R, L and C parameters of the different parts of the chest, basing on different models; the input and output measured data were constituted by the volume variations of the different chest wall compartments and by the nasal pressure during controlled intermittent positive pressure ventilation by nasal mask, while the parameters of the system (R, L and C of the different compartments) were to be estimated. Volumes were measured with a new method, recently validated, based on an opto-electronic motion analyzer, able to compute with high accuracy and null invasivity the absolute values and the time variations of the volumes of each of the three compartments. The estimation of the R, L and C parameters has been based on a least-squared criterion, and the minimization has been based on a robustified iterative Gauss-Newton algorithm. The validation of the estimation procedure (fitting) has ben performed computing the percentage root mean square value of the error between the output real data and the output estimated data. The method has been applied to 2 healthy subjects. Also preliminary results have been obtained from 20 subjects affected by neuromuscular diseases (Duchenne Muscular Dystrophy (DMD) and Spinal Muscle Atrophy (SMA)). The results show that: (a) the best-fitting electrical models of the respiratory system are made up by one or three parallel RLC branches supplied by a voltage generator (so considering inertial properties, particularly in the abdominal compartment, and not considering patient/machine connection); (b) there

  4. Spin Hall driven domain wall motion in magnetic bilayers coupled by a magnetic oxide interlayer

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Furuta, Masaki; Zhu, Jian-Gang Jimmy

    2018-05-01

    mCell, previously proposed by our group, is a four-terminal magnetoresistive device with isolated write- and read-paths for all-spin logic and memory applications. A mCell requires an electric-insulating magnetic layer to couple the spin Hall driven write-path to the magnetic free layer of the read-path. Both paths are magnetic layers with perpendicular anisotropy and their perpendicularly oriented magnetization needs to be maintained with this insertion layer. We have developed a magnetic oxide (FeOx) insertion layer to serve for these purposes. We show that the FeOx insertion layer provides sufficient magnetic coupling between adjacent perpendicular magnetic layers. Resistance measurement shows that this magnetic oxide layer can act as an electric-insulating layer. In addition, spin Hall driven domain wall motion in magnetic bi-layers coupled by the FeOx insertion layer is significantly enhanced compared to that in magnetic single layer; it also requires low voltage threshold that poses possibility for power-efficient device applications.

  5. Optical pathology study of human abdominal aorta tissues using confocal micro resonance Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Liu, Cheng-hui; Boydston-White, Susie; Wang, Wubao; Sordillo, Laura A.; Shi, Lingyan; Weisberg, Arel; Tomaselli, Vincent P.; Sordillo, Peter P.; Alfano, Robert R.

    2016-03-01

    Resonance Raman (RR) spectroscopic technique has a high potential for label-free and in-situ detection of biomedical lesions in vivo. This study evaluates the ability of RR spectroscopy method as an optical histopathology tool to detect the atherosclerotic plaque states of abdominal aorta in vitro. This part demonstrates the RR spectral molecular fingerprint features from different sites of the atherosclerotic abdominal aortic wall tissues. Total 57 sites of five pieces aortic samples in intimal and adventitial wall from an autopsy specimen were examined using confocal micro Raman system of WITec 300R with excitation wavelength of 532nm. The preliminary RR spectral biomarkers of molecular fingerprints indicated that typical calcified atherosclerotic plaque (RR peak at 964cm-1) tissue; fibrolipid plaque (RR peaks at 1007, 1161, 1517 and 2888cm-1) tissue, lipid pool with the fatty precipitation cholesterol) with collagen type I (RR peaks at 864, 1452, 1658, 2888 and 2948cm-1) in the soft tissue were observed and investigated.

  6. Is the great attractor really a great wall

    NASA Technical Reports Server (NTRS)

    Stebbins, Albert; Turner, Michael S.

    1988-01-01

    Some of the cosmological consequences are discussed of a late time phase transition which produces light domain walls. The observed peculiar velocity field of the Universe and the observed isotropy of the microwave background radiation severely constrain the wall surface density in such a scenario. The most interesting consequence of such a phase transition is the possibility that the local, coherent streaming motion reported by the Seven Samurai could be explained by the repulsive effect of a relic domain wall with the Hubble volume (the Great Wall).

  7. Isolated endometriosis on the rectus abdominis muscle in women without a history of abdominal surgery: a rare and intriguing finding.

    PubMed

    Granese, Roberta; Cucinella, Gaspare; Barresi, Valeria; Navarra, Giuseppe; Candiani, Massimo; Triolo, Onofrio

    2009-01-01

    We report 2 rare cases of endometriosis on the rectus abdominal muscle diagnosed incidentally during an operation for inguinal hernia repair in women with no surgical history. Two women sought medical attention for a mass found in the pubic abdominal wall. Only 1 woman reported occasional pain. At physical examination in both women, an ovoid swelling in the right pubic area was felt. One woman experienced pain on palpation, and one reported slight discomfort. Ultrasonography demonstrated a heterogeneous hypoechogenic formation with indistinct edges; diagnosis was difficult. Routine clinical and instrumental (pelvic ultrasonography) gynecologic examination in both patients performed shortly before hospitalization had not revealed any macroscopic focus of endometriosis in the pelvic region. At surgery, a lesion consistent with the diagnosis of endometriosis was found, which was confirmed at histologic analysis. These cases could represent the consolidation of different theories of endometriosis diffusion. We suggest including endometriosis in the differential diagnosis of a symptomatic mass in the abdominal wall in women with and without a surgical history.

  8. 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

  9. Current-controlled unidirectional edge-meron motion

    NASA Astrophysics Data System (ADS)

    Xing, Xiangjun; Pong, Philip W. T.; Zhou, Yan

    2016-11-01

    In order to address many of the challenges and bottlenecks currently experienced by traditional charge-based technologies, various alternatives are being actively explored to provide potential solutions of device miniaturization and scaling in the post-Moore's-law era. Amongst these alternatives, spintronic physics and devices have recently attracted rapidly increasing interest by exploiting the additional degree of electrons-spin. For example, magnetic domain-wall racetrack-memory and logic devices have been realized via manipulating domain-wall motion. As compared to domain-wall-based devices, magnetic skyrmions have the advantages of ultrasmall size (typically 5-100 nm in diameter), facile current-driven motion, topological stability, and peculiar emergent electrodynamics, promising for next-generation electronics applications in the post-Moore's-law regime. Here, a magnetic meron device, which behaves similarly to a PN-junction diode, is demonstrated for the first time, by tailoring the current-controlled unidirectional motion of edge-merons (i.e., fractional skyrmions) in a nanotrack with interfacial Dzyaloshinskii-Moriya interaction. The working principles of the meron device, theoretically predicted from the Thiele equation for topological magnetic objects, are further verified using micromagnetic simulations. The present study has revealed the topology-independent transport property of different magnetic objects and is expected to open the vista toward integrated composite circuitry (with unified data storage and processing) based on a single magnetic chip, as the meron device can be used, either as a building block to develop complex logic components or as a signal controller to interconnect skyrmion, domain-wall, and even spin-wave devices.

  10. Towards remote assessment and screening of acute abdominal pain using only a smartphone with native accelerometers.

    PubMed

    Myers, David R; Weiss, Alexander; Rollins, Margo R; Lam, Wilbur A

    2017-10-06

    Smartphone-based telehealth holds the promise of shifting healthcare from the clinic to the home, but the inability for clinicians to conduct remote palpation, or touching, a key component of the physical exam, remains a major limitation. This is exemplified in the assessment of acute abdominal pain, in which a physician's palpation determines if a patient's pain is life-threatening requiring emergency intervention/surgery or due to some less-urgent cause. In a step towards virtual physical examinations, we developed and report for the first time a "touch-capable" mHealth technology that enables a patient's own hands to serve as remote surrogates for the physician's in the screening of acute abdominal pain. Leveraging only a smartphone with its native accelerometers, our system guides a patient through an exact probing motion that precisely matches the palpation motion set by the physician. An integrated feedback algorithm, with 95% sensitivity and specificity, enabled 81% of tested patients to match a physician abdominal palpation curve with <20% error after 6 attempts. Overall, this work addresses a key issue in telehealth that will vastly improve its capabilities and adoption worldwide.

  11. Schematic construction of flanged nanobearings from double-walled carbon nanotubes.

    PubMed

    Shenai, Prathamesh Mahesh; Zhao, Yang

    2010-08-01

    The performance of nanobearings constructed from double walled carbon nanotubes is considered to be crucially dependent on the initial rotational speed. Wearless rotation ceases for a nanobearing operating beyond a certain angular velocity. We propose a new design of nanobearings by manipulation of double walled carbon nanotubes leading to a flanged structure which possesses a built-in hindrance to the intertube oscillation without obstructing rotational motion. Through blocking the possible leakage path for rotational kinetic energy to the intertube oscillatory motion, the flanged bearing lowers its dissipative tendency when set into motion. Using molecular dynamics, it is shown that on account of its distinctive structure, the flanged bearing has superior operating characteristics and a broader working domain.

  12. Management of intra-abdominal hypertension and abdominal compartment syndrome: a review

    PubMed Central

    2014-01-01

    Patients in the intensive care unit (ICU) are at risk of developing of intra abdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Aim: This review seeks to define IAH and ACS, identify the aetiology and presentation of IAH and ACS, identify IAP measurement techniques, identify current management and discuss the implications of IAH and ACS for nursing practice. A search of the electronic databases was supervised by a health librarian. The electronic data bases Cumulative Index of Nursing and Allied Health Literature (CINAHL); Medline, EMBASE, and the World Wide Web was undertaken from 1996- January 2011 using MeSH and key words which included but not limited to: abdominal compartment syndrome, intra -abdominal hypertension, intra-abdominal pressure in adult populations met the search criteria and were reviewed by three authors using a critical appraisal tool. Data derived from the retrieved material are discussed under the following themes: (1) etiology of intra-abdominal hypertension; (2) strategies for measuring intra-abdominal pressure (3) the manifestation of abdominal compartment syndrome; and (4) the importance of nursing assessment, observation and interventions. Intra-abdominal pressure (IAP) and abdominal compartment syndrome (ACS) have the potential to alter organ perfusion and compromise organ function. PMID:24499574

  13. Real-time correction of beamforming time delay errors in abdominal ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Rigby, K. W.

    2000-04-01

    The speed of sound varies with tissue type, yet commercial ultrasound imagers assume a constant sound speed. Sound speed variation in abdominal fat and muscle layers is widely believed to be largely responsible for poor contrast and resolution in some patients. The simplest model of the abdominal wall assumes that it adds a spatially varying time delay to the ultrasound wavefront. The adequacy of this model is controversial. We describe an adaptive imaging system consisting of a GE LOGIQ 700 imager connected to a multi- processor computer. Arrival time errors for each beamforming channel, estimated by correlating each channel signal with the beamsummed signal, are used to correct the imager's beamforming time delays at the acoustic frame rate. A multi- row transducer provides two-dimensional sampling of arrival time errors. We observe significant improvement in abdominal images of healthy male volunteers: increased contrast of blood vessels, increased visibility of the renal capsule, and increased brightness of the liver.

  14. Advanced age does not affect abdominal wall reconstruction outcomes using acellular dermal matrix: A comparative study using propensity score analysis.

    PubMed

    Giordano, Salvatore; Schaverien, Mark; Garvey, Patrick B; Baumann, Donald P; Liu, Jun; Butler, Charles E

    2017-06-01

    We hypothesized that elderly patients (≥65 years) experience worse outcomes following abdominal wall reconstruction (AWR) for hernia or oncologic resection. We included all consecutive patients who underwent complex AWR using acellular dermal matrix (ADM) between 2005 and 2015. Propensity score analysis was performed for risk adjustment in multivariable analysis and for one-to-one matching. The primary outcome was hernia recurrence; the secondary outcomes included surgical site occurrence (SSO) and bulging. Mean follow-up for the 511 patients was 31.4 months; 184 (36%) patients were elderly. The elderly and non-elderly groups had similar rates of hernia recurrence (7.6% vs 10.1%, respectively; p = 0.43) and SSO (24.5% vs 23.5%, respectively; p = 0.82). Bulging occurred significantly more often in elderly patients (6.5% vs 2.8%, respectively; p = 0.04). After adjustment through the propensity score, which included 130 pairs, these results persisted. Contrary to our hypothesis, elderly patients did not have worse outcomes in AWR with ADM. Surgeons should not deny elderly patients AWR solely because of their age. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Myosonographic study of abdominal wall dynamics to assess donor site morbidity after microsurgical breast reconstruction with a DIEP or an ms-2 TRAM flap.

    PubMed

    Seidenstuecker, K; Legler, U; Munder, B; Andree, C; Mahajan, A; Witzel, C

    2016-05-01

    Currently, autologous breast reconstruction with a free tissue transfer from the lower abdomen is considered to be a safe method that provides a stable long-term solution. The DIEP-flap and the ms-2-TRAM-flap reconstructions have helped reduce donor site morbidity. In order to assess the potential differences between these techniques, we carried out myosonographic evaluations that assessed the muscle dynamics pre- and post-operatively. In addition to investigating the properties of the rectus abdominis muscle post-operatively, this prospective study also allowed us to analyse the muscle preoperatively and to investigate the prospects for harvesting a DIEP-flap as opposed to a TRAM-flap. Sixty patients underwent breast reconstruction with 71 (11 bilateral) free abdominal wall flaps (DIEP-: n = 48; ms-2-TRAM-flap: n = 23). Myosonographic examinations were performed preoperatively and at 3 and 6 months post-operatively. The thickness of the muscle at relaxation and maximum contraction and the difference between the muscle thickness measured at the two states were measured. A general-linear-model (GLM) was used for statistical analysis. The main variable was the surgical method, and the co-variables included BMI and patient age. The decision on whether to harvest a DIEP- or ms-2-TRAM-flap was made intra-operatively and based on the dominant perforator. It shows that the patients who underwent breast reconstruction with a DIEP-flap had significantly better muscle function (p < 0.05) in the follow-up. In addition, the analysis revealed that better muscle function before surgery made it more likely that a patient would undergo a DIEP-flap-reconstruction successfully. Patient age also had a highly significant effect on muscle recovery (p < 0.0005). This prospective study used a dynamic ultrasound evaluation of the abdominal wall and showed that the DIEP-flap significantly reduces donor site morbidity compared to the ms-2-TRAM-flap. The study also showed that good

  16. The predictive value of 201Tl rest-redistribution and 18F-fluorodeoxyglucose SPECT for wall motion recovery after recent reperfused myocardial infarction.

    PubMed

    González, Patricio; Massardo, Teresa; Coll, Claudia; Humeres, Pamela; Sierralta, Paulina; Jofré, M Josefina; Yovanovich, Jorge; Aramburu, Ivonne; Brugère, Solange; Chamorro, Hernán

    2004-04-01

    201Tl and 18F-FDG are useful for acute myocardial infarction (MI) assessment. The goal of this study was to compare their predictive value for wall motion recovery in the culprit area after a recent reperfused MI using SPECT technique. Forty-one patients (mean age: 56 +/- 12 years) were included, 81% of them male; all were studied within 1-24 days post MI. They underwent angioplasty in 27 cases (12 primary); bypass grafting in 10 cases and successful thrombolysis in 4. SPECT 201Tl injected at rest and redistribution (R-R) and also 18F-FDG, were performed on different days. Processed tomograms were interpreted blinded to clinical or angiographic data. Segmental wall motion assessed with echocardiography at baseline was compared with the 3 month follow up. Sensitivity [Confidence Interval] for 201Tl R-R was 74.6% [60.5-84.5], for FDG it was 82.1% [70.8-90.4]; specificities were 73% [64.3-80.5] and 54.8% [45.6-63.7], respectively. 18F-FDG tended to be more sensitive than 201Tl R-R, but the latter was more specific (p < 0.0004). Both 201Tl RR and 18F-FDG presented high negative predictive value (p: ns). In recent MI, SPECT 201Tl R-R is a valuable and widely available technique for viability detection, with similar sensitivity and significant better specificity than SPECT 18F-FDG.

  17. Wall-motion tracking in fetal echocardiography-Influence of frame rate on longitudinal strain analysis assessed by two-dimensional speckle tracking.

    PubMed

    Enzensberger, Christian; Achterberg, Friederike; Graupner, Oliver; Wolter, Aline; Herrmann, Johannes; Axt-Fliedner, Roland

    2017-06-01

    Frame rates (FR) used for strain analysis assessed by speckle tracking in fetal echocardiography show a considerable variation. The aim of this study was to investigate the influence of the FR on strain analysis in 2D speckle tracking. Fetal echocardiography was performed prospectively on a Toshiba Aplio 500 system and a Toshiba Artida system, respectively. Based on an apical or basal four-chamber view of the fetal heart, cine loops were stored with a FR of 30 fps (Aplio 500) and 60 fps (Artida/Aplio 500). For both groups (30fps and 60fps), global and segmental longitudinal peak systolic strain (LPSS) values of both, left (LV) and right ventricle (RV), were assessed by 2D wall-motion tracking. A total of 101 fetuses, distributed to three study groups, were included. The mean gestational age was 25.2±5.0 weeks. Mean global LPSS values for RV in the 30 fps group and in the 60 fps group were -16.07% and -16.47%, respectively. Mean global LPSS values for LV in the 30 fps group and in the 60 fps group were -17.54% and -17.06%, respectively. Comparing global and segmental LPSS values of both, the RV and LV, did not show any statistically significant differences within the two groups. Performance of myocardial 2D strain analysis by wall-motion tracking was feasible with 30 and 60 fps. Obtained global and segmental LPSS values of both ventricles were relatively independent from acquisition rate. © 2017, Wiley Periodicals, Inc.

  18. How to push a block along a wall

    NASA Technical Reports Server (NTRS)

    Mason, Matthew T.

    1989-01-01

    Some robot tasks require manipulation of objects that may be touching other fixed objects. The effects of friction and kinematic constraint must be anticipated, and may even be exploited to accomplish the task. An example task, a dynamic analysis, and appropriate effector motions are presented. The goal is to move a rectangular block along a wall, so that one side of the block maintains contact with the wall. Two solutions that push the block along the wall are discussed.

  19. Abdominal cysticercosis in a rhesus macaque (Macaca mulatta).

    PubMed

    Hobbs, Theodore R; Colgin, Lois M A; Maginnis, Gwendalyn M; Lewis, Anne D

    2003-10-01

    A mid-abdominal mass was discovered during routine physical examination of a rhesus macaque (Macaca mulatta). Further diagnostics and exploratory laparotomy were performed, revealing a fluid-filled cyst attached to the caudal free margin of the greater omentum. Formation and pulsatile movement of white-colored circumferential bands within the wall of the cyst were observed during surgery. The cyst was removed and later was dissected. The discovery of a single invaginated scolex identified the cyst as a cysticercus. The location and characteristics of the cysticercus were consistent with the larval form of Taenia hydatigena.

  20. [Minilaparoscopy in penetrating abdominal trauma emergency room procedure with local anesthesia].

    PubMed

    Ariel, Peralta; Sebastián, Vélez; Sergio, Locicero; Nicolini, Francisco Florez

    2007-01-01

    There are a number of unnecessary laparotomies in penetrating trauma, with a non worthless percentage of complications. When the peritoneal injury is identified, surgical exploration of the abdomen should be evaluated. Evaluate the penetration of the peritoneum, using a diagnose method with direct vision. Hospital de Urgencias de Córdoba. Trauma Hospital. To evidence peritoneum trespassing, laparoscopy was performed with local anaesthesia in patients with penetrating abdominal trauma without signs of abdominal injury in the imaging methods and doubts in the physical examination, in a prospective setting. Patient with penetrating abdominal trauma, treated between May 2004 to January 2005, with doubtful diagnose of peritoneal violation. Under sedation and local anaesthesia, a 5 millimetres laparoscope with 90 degrees vision was placed at umbilicus. The anterior abdominal wall, flanks and diaphragm were exanimate, looking for the peritoneal wound or free fluid. Laparotomy could be avoided in four patients. In the four remaining, laparoscopy or conventional surgery was performed. Two presented hollow viscera injury, one hemoperitoneo and the other, minimum liver damage. There were not complications in both groups. The average hospital stay of the first group was 13 hours. In selected patients, the minilaparoscopy is useful in decreased the percentage of unnecessary laparotomies and general anaesthesia, and its complications.