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Sample records for abdominal wall thickness

  1. 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

  2. The effect of full-thickness abdominal wall burns sustained during childhood on subsequent childbearing ability.

    PubMed

    Kitzmiller, W J; Neale, H W; Warden, G D; Smith, D

    1998-02-01

    The effect of full-thickness burns of the abdomen during childhood on subsequent pregnancy was evaluated. Eight hundred female pediatric patients treated for acute burns during a 14-year period (1975-1989) at the Shriners Burns Institute were reviewed. Through a combination of clinical follow-up, questionnaires, or phone interviews, data were obtained regarding the histories of 31 pregnancies in 19 patients who had required excision and skin grafting of > or = 50% of their abdominal wall during management of their acute burns. These patients sustained a mean burn size of 59.8% total body surface area (TBSA; range, 23-87%) with a mean full-thickness burn of 43.8% TBSA (range, 10-78%). The mean age at the time of burn was 7.6 years (range, 1.5-15 years). Normal rates of vaginal and cesarean section deliveries, prematurity, and infant mortality were observed in these 31 pregnancies. Despite a subjective sensation of increased tension on the scar in 25% of the patients, no interference with these patients carrying a full-term pregnancy directly attributable to the burn scar was identified. Follow-up and examination during the third trimester of pregnancy demonstrated how the burned and unburned portion of the abdominal wall accommodated the enlarged uterus. This review demonstrates that after extensive burns to the abdomen, which have been treated with excision and skin grafting during childhood, the scarred abdominal wall accommodates full-term pregnancy without the need for surgical release. PMID:9495456

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

    SciTech Connect

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

    2010-02-15

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

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

    PubMed

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

    2016-06-01

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

  5. Abdominal wall surgery

    MedlinePlus

    ... tummy tuck. It can range from a simple mini-tummy tuck to more extensive surgery. Abdominal wall ... abdomen. Your abdominal muscles may be tightened also. Mini abdominoplasty is performed when there are areas of ...

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

    PubMed Central

    Kok, Amy Siu Yan

    2016-01-01

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

  7. Comparison of the Changes in Thickness of the Abdominal Wall Muscles of Stroke Patients According to the Duration of Their Illness as Observed Using Ultrasonographic Images

    PubMed Central

    Seo, DongKwon; Lee, SeungWon; Kwon, OhSung

    2013-01-01

    [Purpose] This study was conducted in order to investigate the importance of trunk muscle strength in stroke patients. By comparing the thicknesses of the abdominal wall muscles through ultrasonography, relative to the duration of illness, the results of the objective data were applied. [Methods] Thirty stroke patients were divided into three groups including an acute phase group participating in the study within 1 month after the onset of a stroke (n=10), a subacute phase group participating less than 6 months (n=10) after a stroke, and a chronic phase group participating more than 6 months (n=10) after suffering a stroke. The thicknesses of the transversus abdominis muscles (TrA), internal oblique muscle (IO), and the external oblique muscle (EO) were measured at rest and during abdominal draw-in maneuver (ADIM) in a supine hook-lying position, and their differences were compared. [Results] The results showed that, in comparison of the thicknesses of the paretic and nonparetic sides, the TrA of the subacute phase and chronic phase groups showed significant differences. In addition, the IO of the subacute phase group and the EO of the chronic phase groups also showed significant differences. [Conclusion] According to the duration of illness in stroke patients, the abdominal wall muscles become noticeably infirm and asymmetric. By improving their symmetry, the functions of the trunk muscles can be recovered. PMID:24259861

  8. Comparison of the changes in thickness of the abdominal wall muscles of stroke patients according to the duration of their illness as observed using ultrasonographic images.

    PubMed

    Seo, Dongkwon; Lee, Seungwon; Kwon, Ohsung

    2013-07-01

    [Purpose] This study was conducted in order to investigate the importance of trunk muscle strength in stroke patients. By comparing the thicknesses of the abdominal wall muscles through ultrasonography, relative to the duration of illness, the results of the objective data were applied. [Methods] Thirty stroke patients were divided into three groups including an acute phase group participating in the study within 1 month after the onset of a stroke (n=10), a subacute phase group participating less than 6 months (n=10) after a stroke, and a chronic phase group participating more than 6 months (n=10) after suffering a stroke. The thicknesses of the transversus abdominis muscles (TrA), internal oblique muscle (IO), and the external oblique muscle (EO) were measured at rest and during abdominal draw-in maneuver (ADIM) in a supine hook-lying position, and their differences were compared. [Results] The results showed that, in comparison of the thicknesses of the paretic and nonparetic sides, the TrA of the subacute phase and chronic phase groups showed significant differences. In addition, the IO of the subacute phase group and the EO of the chronic phase groups also showed significant differences. [Conclusion] According to the duration of illness in stroke patients, the abdominal wall muscles become noticeably infirm and asymmetric. By improving their symmetry, the functions of the trunk muscles can be recovered. PMID:24259861

  9. A thick-walled fluid-solid-growth model of abdominal aortic aneurysm evolution: application to a patient-specific geometry.

    PubMed

    Grytsan, Andrii; Watton, Paul N; Holzapfel, Gerhard A

    2015-03-01

    We propose a novel thick-walled fluid-solid-growth (FSG) computational framework for modeling vascular disease evolution. The arterial wall is modeled as a thick-walled nonlinearly elastic cylindrical tube consisting of two layers corresponding to the media-intima and adventitia, where each layer is treated as a fiber-reinforced material with the fibers corresponding to the collagenous component. Blood is modeled as a Newtonian fluid with constant density and viscosity; no slip and no-flux conditions are applied at the arterial wall. Disease progression is simulated by growth and remodeling (G&R) of the load bearing constituents of the wall. Adaptions of the natural reference configurations and mass densities of constituents are driven by deviations of mechanical stimuli from homeostatic levels. We apply the novel framework to model abdominal aortic aneurysm (AAA) evolution. Elastin degradation is initially prescribed to create a perturbation to the geometry which results in a local decrease in wall shear stress (WSS). Subsequent degradation of elastin is driven by low WSS and an aneurysm evolves as the elastin degrades and the collagen adapts. The influence of transmural G&R of constituents on the aneurysm development is analyzed. We observe that elastin and collagen strains evolve to be transmurally heterogeneous and this may facilitate the development of tortuosity. This multiphysics framework provides the basis for exploring the influence of transmural metabolic activity on the progression of vascular disease. PMID:25473877

  10. Reconstruction of disruption of the abdominal wall in burn patients.

    PubMed

    Still, J M; Dimick, A R; Dawson, J; Law, E

    1999-04-01

    Two patients with extensive destruction of the full thickness of the abdominal wall and associated intra-abdominal injuries were encountered. One case resulted from burns to a patient pinned under an automobile in contact with the muffler; the other was injured as a result of penetration of the abdominal wall by a railroad coupling and was also burned in an associated welding accident at the same time. Extensive staged debridement and repair of intra-abdominal injuries in several procedures were required in case 1. Closure was eventually achieved with serial applications of mesh and split-thickness autografting. In case 2, an initial attempt at flap closure failed. Coverage initially was obtained with silicone mesh followed by split-thickness grafting. We report successful management of two of these difficult reconstructive challenges. PMID:10190445

  11. Genetics Home Reference: abdominal wall defect

    MedlinePlus

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

  12. Management of Postoperative Abdominal Wall Pain.

    PubMed

    Sharp, Howard T

    2015-12-01

    Postoperative incisional pain is expected after surgery. However, when a patient is complaining of pain months after surgery, this can be a source of frustration and confusion to the patient and the surgeon. Whether the pain is a result of myofascial pain, incisional hernia, or nerve injury, understanding potential sources of abdominal wall pain can simplify this diagnostic dilemma. This chapter will focus on the diagnosis, treatment, and prevention of postsurgical abdominal wall pain. PMID:26512441

  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. Intraabdominal Challenges Affecting Abdominal Wall Reconstruction

    PubMed Central

    Moffett, Jennifer Movassaghi; Gedalia, Uri; Xue, Amy Shengnan; Heller, Lior

    2012-01-01

    Abdominal wall defects may arise from trauma, infection, and prior abdominal surgeries, such as tumor resections. Although ideally reconstruction should be accomplished as soon as possible to restore the integrity and function of the abdominal wall, it is not always a viable option. A successful reconstruction must take into consideration the local environment of the defect, as well as the global condition of the patient. Therefore, it is imperative that a multidisciplinary team be involved to optimize the patient's care, particularly when a defect is complicated by a wound infection, an abscess, a fistula, or a neoplasm. Our goal in this article is to explore the challenges evoked by each of these special situations, and review the necessary steps for successful management. PMID:23372452

  15. Abdominal wall herniae and their underlying pathology

    PubMed Central

    Upchurch, Emma; Al-Akash, Musallam

    2016-01-01

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

  16. Teratogenic aspects of abdominal wall defects.

    PubMed

    Lindham, S

    1983-08-01

    The article describes two methods used to reveal possible teratogenic factors involved in the aetiology of abdominal wall defects. Forty-six mothers to children with gastroschisis and omphalocele were questioned about heredity, occupation, use of drugs etc. during early pregnancy (case history study). Seventy-four mothers to children with gastroschisis and omphalocele were randomly selected from a national register and their maternal health service record forms were studied and compared with the forms of 144 matched controls (case control study). None of the analyzed factors was found to be of significant teratogenic importance in the aetiology of abdominal wall defects, nor was it possible to explain the increase in the incidence of gastroschisis taking place during the early 70s. PMID:6227161

  17. Turbine airfoil with outer wall thickness indicators

    DOEpatents

    Marra, John J; James, Allister W; Merrill, Gary B

    2013-08-06

    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  18. Abdominal Wall Schwannoma: Case Report and Review of the Literature

    PubMed Central

    Mishra, A.; Hamadto, M.; Azzabi, M.; Elfagieh, M.

    2013-01-01

    A 29-year-old female had presented to surgical outpatient's department complaining of lump in the anterior abdominal wall. Ultrasound and magnetic resonance imaging revealed a solid degenerated tumor in the anterior abdominal wall. It was surgically excised, and histopathology confirmed it to be “ancient” schwannoma. To our knowledge, this is the second reported case of an abdominal wall ancient schwannoma in the medical literature. PMID:23841008

  19. Ultrasonographic evaluation of gallbladder wall thickness in cats.

    PubMed

    Hittmair, K M; Vielgrader, H D; Loupal, G

    2001-01-01

    Ultrasonography of the gallbladder and biliary tract was performed on 42 cats: 22 clinically healthy cats (group A) and 20 cats with hepatobiliary disease and post mortem confirmation of gallbladder abnormalities (group B). The gallbladder wall was visible in 9 of 22 cats in group A and all 20 cats in group B. Additional gallbladder findings in group B included shape anomalies, biliary tract obstruction, wall thickening, polyps, neoplasia, and biliary sludge. Ultrasonographic evaluation of abdominal organs identified pancreatic disease as the predominant pathological cause of extrahepatic biliary obstruction. Hepatic parenchymal involvement was noted with inflammation and thickening of the gallbladder wall. Histologically, gallbladder walls were characterized by mucous gland hyperplasia, inflammation, infiltration, edema, epithelial detachment, and/or neoplasia. Ultrasonographic and histologic gallbladder wall measurements of 20 cats in group B agreed within 0.4 mm and all cats with a gallbladder wall thickness > or =1.0 mm had histopathologic abnormalities of the wall. Serum biochemical analysis revealed elevations of one or more parameters in all cats of group B, but was non-specific for a gallbladder lesion. The results of this study indicate that a visible, echogenic gallbladder wall can be considered a normal variant and is not always associated with hepatobiliary disease. Ultrasonography is accurate in measuring gallbladder wall thickness. Wall thickness greater than 1 mm is accurate in predicting gallbladder disease in cats, while a thickness less than 1 mm cannot rule out mild or chronic inflammation. PMID:11327363

  20. Tensor fascia lata musculocutaneous flap for abdominal wall reconstruction

    SciTech Connect

    Peled, I.J.; Kaplan, H.Y.; Herson, M.; Wexler, M.R.

    1983-08-01

    We report a case of abdominal wall reconstruction following excision of irradiated skin and a ventral hernia. A very large tensor fascia lata musculocutaneous flap was used with good results. The anatomical features of this flap make it an excellent method of abdominal wall reconstruction.

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

    PubMed

    Latifi, Rifat

    2016-04-01

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

  2. Tube-Wall Thickness Detector

    NASA Technical Reports Server (NTRS)

    Kleint, R. E.; Baily, R. D.

    1985-01-01

    Eddy-current measurements detect wear of thin walls (0.01 in) (0.25 mm) in small diameter (0.19 in) (5 mm) heat exchanger tubing. Flexible durable thin rod inserts eddy-current coil into the heatexchanger tube.

  3. Body wall dysplasia: a rare case of abdominal hernia.

    PubMed

    Queizán, A; Rivas, S; Hernández, F; Martínez, L

    2005-05-01

    Malformations of the fetal abdominal wall include a broad spectrum of anomalies, and prenatal sonography provides the possibility of detecting most of them. Omphalocele and gastroschisis are the most common conditions, but there are other rare forms. We describe here a rare case of body wall dysplasia that we called abdominal hernia that appeared upon prenatal sonography as an omphalocele-like defect. PMID:15937837

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

    PubMed Central

    Wilson, Kenneth L.; Rosser, James C.

    2012-01-01

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

  5. Wall thickness measuring method and apparatus

    DOEpatents

    Salzer, Leander J.; Bergren, Donald A.

    1989-01-01

    An apparatus for measuring the wall thickness of a nonmagnetic article having a housing supporting a magnet and a contiguous supporting surface. The tubular article and the housing are releasably secured to the supporting surface and a support member of an optical comparator, respectively. To determine the wall thickness of the article at a selected point, a magnetically responsive ball is positioned within the tubular article over said point and retained therein by means of a magnetic field produced by the magnet. Thereafter, an optical comparator is employed to project a magnified image of the ball on a screen and the wall thickness at the selected point is calculated by using a ball surface measurement taken with the comparator in conjunction with a previously determined base line measurement.

  6. Wall thickness measuring method and apparatus

    DOEpatents

    Salzer, L.J.; Bergren, D.A.

    1987-10-06

    An apparatus for measuring the wall thickness of a nonmagnetic article having a housing supporting a magnet and a contiguous supporting surface. The tubular article and the housing are releasably secured to the supporting surface and a support member of an optical comparator, respectively. To determine the wall thickness of the article at a selected point, a magnetically responsive ball is positioned within the tubular article over said point and retained therein by means of a magnetic field produced by the magnet. Thereafter, an optical comparator is employed to project a magnified image of the ball on a screen and the wall thickness at the selected point is calculated by using a ball surface measurement taken with the comparator in conjunction with a previously determined base line measurement.

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2014-01-01

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

  9. Emergency abdominal wall defects in neonates: saved by distress.

    PubMed

    Fawkner-Corbett, David William; Shepherd, Gregory; Lakhoo, Kokila

    2016-01-01

    This report presents two cases of neonatal patients with abdominal wall defects requiring emergency intervention, a closing gastroschisis and a pedunculated exomphalos with eviscerated liver. Both presented as pre-partum fetal distress and were delivered in a tertiary centre, where they received antenatal care. Coordination in the multidisciplinary team and prompt surgical intervention prevented loss of the eviscerated abdominal contents and prevented mortality in both cases. PMID:27030461

  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. The Pilates Method increases respiratory muscle strength and performance as well as abdominal muscle thickness.

    PubMed

    Giacomini, Mateus Beltrame; da Silva, Antônio Marcos Vargas; Weber, Laura Menezes; Monteiro, Mariane Borba

    2016-04-01

    The aim of this study was to verify the effects of the Pilates Method (PM) training program on the thickness of the abdominal wall muscles, respiratory muscle strength and performance, and lung function. This uncontrolled clinical trial involved 16 sedentary women who were assessed before and after eight weeks of PM training. The thickness of the transversus abdominis (TrA), internal oblique (IO) and external oblique (EO) muscles was assessed. The respiratory muscle strength was assessed by measuring the maximum inspiratory (MIP) and expiratory (MEP) pressure. The lung function and respiratory muscle performance were assessed by spirometry. An increase was found in MIP (p = 0.001), MEP (p = 0.031), maximum voluntary ventilation (p = 0.020) and the TrA (p < 0.001), IO (p = 0.002) and EO (p < 0.001) thickness after the PM program. No alterations in lung function were found. These findings suggest that the PM program promotes abdominal wall muscle hypertrophy and an increase in respiratory muscle strength and performance, preventing weakness in abdominal muscles and dysfunction in ventilatory mechanics, which could favor the appearance of illnesses. PMID:27210841

  12. Reproducibility of airway wall thickness measurements

    NASA Astrophysics Data System (ADS)

    Schmidt, Michael; Kuhnigk, Jan-Martin; Krass, Stefan; Owsijewitsch, Michael; de Hoop, Bartjan; Peitgen, Heinz-Otto

    2010-03-01

    Airway remodeling and accompanying changes in wall thickness are known to be a major symptom of chronic obstructive pulmonary disease (COPD), associated with reduced lung function in diseased individuals. Further investigation of this disease as well as monitoring of disease progression and treatment effect demand for accurate and reproducible assessment of airway wall thickness in CT datasets. With wall thicknesses in the sub-millimeter range, this task remains challenging even with today's high resolution CT datasets. To provide accurate measurements, taking partial volume effects into account is mandatory. The Full-Width-at-Half-Maximum (FWHM) method has been shown to be inappropriate for small airways1,2 and several improved algorithms for objective quantification of airway wall thickness have been proposed.1-8 In this paper, we describe an algorithm based on a closed form solution proposed by Weinheimer et al.7 We locally estimate the lung density parameter required for the closed form solution to account for possible variations of parenchyma density between different lung regions, inspiration states and contrast agent concentrations. The general accuracy of the algorithm is evaluated using basic tubular software and hardware phantoms. Furthermore, we present results on the reproducibility of the algorithm with respect to clinical CT scans, varying reconstruction kernels, and repeated acquisitions, which is crucial for longitudinal observations.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-02-01

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

  15. Ultrasonography and computed tomography of inflammatory abdominal wall lesions

    SciTech Connect

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

    1982-09-01

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

  16. On thick domain walls in general relativity

    NASA Technical Reports Server (NTRS)

    Goetz, Guenter; Noetzold, Dirk

    1989-01-01

    Planar scalar field configurations in general relativity differ considerably from those in flat space. It is shown that static domain walls of finite thickness in curved space-time do not possess a reflection symmetry. At infinity, the space-time tends to the Taub vacuum on one side of the wall and to the Minkowski vacuum (Rindler space-time) on the other. Massive test particles are always accelerated towards the Minkowski side, i.e., domain walls are attractive on the Taub side, but repulsive on the Minkowski side (Taub-vacuum cleaner). It is also proved that the pressure in all directions is always negative. Finally, a brief comment is made concerning the possibility of infinite, i.e., bigger than horizon size, domain walls in our universe. All of the results are independent of the form of the potential V(phi) greater than or equal to 0 of the scalar field phi.

  17. Traumatic abdominal wall hernia in two adults: a case series

    PubMed Central

    2009-01-01

    Introduction Traumatic hernia of the abdominal wall is a rare entity. A large proportion of reported cases are in children with a particular type of injury, i.e. from a handlebar injury. In adults, the presentation can vary substantially and the diagnosis is difficult. We present two cases in adults, with widely varying presentations and management. Case presentations A 40-year-old woman from rural north India presented with a low-velocity blunt injury to the lower abdomen. She was attacked by a bull. She had a clinically evident abdominal fascial disruption with intact skin, and was hemodynamically stable. An emergency mesh repair of the defect was performed, and she recovered well. A 38-year-old man from rural north India presented with blunt trauma to the abdomen following a motor vehicle accident. He was stable, with a central abdominal parietal wall swelling and bruising. A computed tomography scan revealed herniation of bowel loops in the area with minor intra-abdominal injuries. A laparotomy, resection-anastomosis of the ischemic bowel, and primary repair of the defect was performed and he recovered well. Conclusion Following blunt abdominal trauma, particularly high-velocity injuries, a high index of suspicion must be reserved for parietal wall swellings, as missed hernias in this setting have a high risk of strangulation. Computed tomography is the best aid to diagnosis. Management of each case needs to be individualized. PMID:19830187

  18. Delamination failure of thick walled composite cylinders

    NASA Astrophysics Data System (ADS)

    Snyder, B.; Dharmarajan, S.

    Failure criteria based on linear fracture mechanics are shown to account for the delamination failures of the thick-walled composite cylinders whose thermally induced stresses are presently computed. This analytical method is applied to CFRP cylinders, in the cases of both uniform thermal loading and various thermal profiles that are typical of the cooling process following the cure cycle. In the former, both radial and circumferential stresses are maximum; in the latter, axial stresses are maximum for thermal profiles where the largest temperature difference is between the inside and outside walls.

  19. Gas turbine bucket wall thickness control

    DOEpatents

    Stathopoulos, Dimitrios; Xu, Liming; Lewis, Doyle C.

    2002-01-01

    A core for use in casting a turbine bucket including serpentine cooling passages is divided into two pieces including a leading edge core section and a trailing edge core section. Wall thicknesses at the leading edge and the trailing edge of the turbine bucket can be controlled independent of each other by separately positioning the leading edge core section and the trailing edge core section in the casting die. The controlled leading and trailing edge thicknesses can thus be optimized for efficient cooling, resulting in more efficient turbine operation.

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

    PubMed

    Abid, Shazia; El-Hayek, Kevin

    2016-03-01

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

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

    PubMed Central

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

    2009-01-01

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

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

    PubMed

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

    2007-11-01

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

  3. Quantitative anatomical labeling of the anterior abdominal wall

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

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

  4. Clear Cell Adenocarcinoma Arising from Abdominal Wall Endometriosis

    PubMed Central

    Achach, Thouraya; Rammeh, Soumaya; Trabelsi, Amel; Ltaief, Rached; Ben Abdelkrim, Soumaya; Mokni, Moncef; Korbi, Sadok

    2008-01-01

    Endometriosis is a frequent benign disorder. Malignancy arising in extraovarian endometriosis is a rare event. A 49-year-old woman is presented with a large painful abdominal wall mass. She underwent a myomectomy, 20 years before, for uterus leiomyoma. Computed tomography suggested that this was a desmoid tumor and she underwent surgery. Histological examination showed a clear cell adenocarcinoma associated with endometriosis foci. Pelvic ultrasound, computed tomography, and endometrial curettage did not show any malignancy or endometriosis in the uterus and ovaries. Adjuvant chemotherapy was recommended, but the patient was lost to follow up. Six months later, she returned with a recurrence of the abdominal wall mass. She was given chemotherapy and then she was reoperated. PMID:19266089

  5. Gastric Wall Thickness in Sleeve Gastrectomy Patients: Thickness Variation of the Gastric Wall.

    PubMed

    van Rutte, Pim W J; Naagen, Bertus J; Spek, Marinus; Jakimowicz, Jack J; Nienhuijs, Simon W

    2015-11-01

    The sleeve gastrectomy has been accepted as a primary bariatric procedure. One of the most feared complications is staple line leakage. It is important to use the right staple sizes to minimize the risk of leak. Knowledge of gastric thickness is important. The goal of this study was to measure the thickness of the gastric wall after elimination of the gastric folds in the mucosa. An electronic thickness gauge was developed that measured the anterior and posterior wall of the fresh stomach specimen together at 5 points at a pressure based on the finger pressure necessary to flatten the gastric folds. Thirty-three fresh specimens were measured. The mean compression pressure was 714 grams, and no difference was found between the 5 measure points. There was a significant difference in stomach wall thickness. The gastric antrum was more than 1 mm thicker than the fundus. No difference was found between BMI groups <40Kg/m2, 40-50Kg/m2, or >50Kg/m2. No bleeding occurred, leakage occurred in 1 case. There is a significant difference in thickness of the stomach wall between the gastric fundus and the antrum. A pressure 2.5 times lower than applied in prior studies was necessary to achieve full tissue compression. Choosing thinner staple sizes for the gastric fundus might be the optimal technique for compression. However, there are several additional factors that influence the risk of staple line leaks. PMID:26680415

  6. Wall thickness effect on the resistive wall mode stability in toroidal plasmas

    SciTech Connect

    Zheng, L.-J.; Kotschenreuther, M.T.

    2005-07-15

    The effect of finite wall thickness on the stability of n=1 resistive wall modes in toroidal plasmas is investigated. A fusion reactor-relevant configuration is examined. The investigation employs a novel ideal-magnetohydrodynamics adaptive shooting code for axisymmetric plasmas, extended to take into account the wall thickness. Although finite wall thickness generally reduces the growth rate of the resistive wall modes, no contribution to stabilization is found to be made by the portion of the wall that is located beyond the critical position for perfectly conducting wall stabilization. Thus, when the inner side of the wall lies near the critical wall position, the scaling of the growth rate versus wall thickness in the realistic thick-wall calculation is significantly different from that of the usual thin-wall theory. The thin-wall estimate is relevant only when the wall is brought very close to the plasma and is not too thick.

  7. Distribution of Wall Stress in Abdominal Aortic Aneurysm (AAA)

    NASA Astrophysics Data System (ADS)

    Lasheras, Juan

    2005-11-01

    Abdominal aortic aneurysm (AAA) rupture is believed to occur when the mechanical stress acting on the wall exceeds the strength of the wall tissue. Therefore, knowledge of the AAA wall stress distribution could be useful in assessing its risk of rupture. In our research, a finite element analysis was used to determine the wall stresses both in idealized models and in a real clinical model in which the aorta was considered isotropic with nonlinear material properties and was loaded with a given pressure. In the idealized models, both maximum diameter and asymmetry were found to have substantial influence on the distribution of the wall stress. The thrombus inside the AAA was also found to help protecting the walls from high stresses. Using CT scans of the AAA, the actual geometry of the aneurysm was reconstructed and we found that wall tension increases on the flatter surface (typically corresponds to the posterior surface) and at the inflection points of the bulge. In addition to the static analysis, we also performed simulations of the effect of unsteady pressure wave propagation inside the aneurysm.

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

    PubMed

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

    2015-01-01

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

  9. Congenital Abdominal Wall Defects: Staged closure by Dual Mesh

    PubMed Central

    Risby, Kirsten; Jakobsen, Marianne Skytte; Qvist, Niels

    2016-01-01

    Objective: To evaluate the clinical utility of GORE® DUALMESH (GDM) in the staged closure of large congenital abdominal wall defects. Materials and Methods: Data of patients with congenital abdominal wall defects managed with GDM was analyzed for outcome regarding complete fascial closure; mesh related complications; and post-discharge gastrointestinal surgery. Results: GDM was placed in 34 (gastroschisis=27, omphalocele=7) patients during the study period. Complete closure of the fascia was obtained in one patient with omphalocele and in 22 patients with gastroschisis. Mesh related surgical complications were seen in five (15%) children: four had detachment of the mesh and one patient developed abdominal compartment syndrome. Mesh related clinical infection was observed in five children. In hospital mortality occurred in four cases (2 gastroschisis and 2 omphalocele) and was not procedure-related. Of the 30 children discharged, 28 (82%) were still alive. At follow-up, three patients (10%) were operated for a minor ventral hernia and 4 children were operated (laparotomy and adhesionolysis) for adhesive intestinal obstruction. Conclusion: Staged closure with GDM is a safe alternative when primary fascial closure is difficult. PMID:26793594

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

    PubMed Central

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

    2015-01-01

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

  11. Effects of the flexibility of the arterial wall on the wall shear stresses and wall tension in Abdominal Aortic Aneurysms.

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Fernandez, Miguel; Chomaz, Jean-Marc

    2005-11-01

    As an abdominal aortic aneurysm develops, large changes occur in the composition and structure of the arterial wall, which result in its stiffening. So far, most studies, whether experimental or numerical, have been conducted assuming the walls to be rigid. A numerical simulation of the fluid structure interactions is performed in different models of aneurysms in order to analyze the effects that the wall compliance might have on the flow topology. Both symmetric and non-symmetric models of aneurysms are considered, all idealistic in shape. The wall mechanical properties are varied in order to simulate the progressive stiffening of the walls. The spatial and temporal distributions of wall tension are calculated for the different values of the wall elasticity and compared to the results for the rigid walls. In the case of rigid walls, the calculation of the wall shear stresses and pressure compare very well with experimental results.

  12. Post-operative Abdominal Wall Mucormycosis-a Case Series.

    PubMed

    Nain, Prabhdeep Singh; Matta, Harish; Singh, Kuldip; Chhina, Deepinder; Trehan, Munish; Batta, Nishant

    2015-12-01

    Mucormycosis is caused by saprophtytic fungi which cause acute invasive zygomycosis. It clinically presents with necrosis, and on histopathology, acute and chronic infiltrates are seen. It rarely infects a healthy host, but is devastating in an immunocompromised host. We studied five cases with post-operative abdominal wall mucormycosis, three females and two males. Three patients were post-operative while the other two had mucormycosis following trauma and infection was found in sutured wound. All were initially diagnosed as cases of necrotizing fasciitis. Two patients eventually survived after intensive medical therapy and extensive debridements. PMID:26730004

  13. Congenital Anaplastic Rhabdomyosarcoma Presenting As Abdominal Wall Mass

    PubMed Central

    Mondal, Krishnendu; Mandal, Rupali

    2016-01-01

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

  14. Changes in wall shear stresses in abdominal aortic aneurysms with increasing wall stiffness

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Fernandez, Miguel

    2006-11-01

    During the growth of abdominal aortic aneurysms, local changes occur in the composition and structure of the diseased wall, resulting in its stiffening. A numerical simulation of the fluid structure interactions is performed in idealized models of aneurysms using a finite element method. A full coupling of the equations governing the pulsatile blood flow and the deformation of the compliant wall is undertaken. The effect of the progressive stiffening of the wall is analyzed at various stages in the growth of the aneurysm. Increasing the wall stiffness alters the distribution of wall shear stresses and leads to an increase in their magnitude. The wall compliance is shown to have a more pronounced effect on non-axisymmetric aneurysms, which sustain large displacements. The overall movement of the aneurysm models increases the three-dimensionality of the flow.

  15. An abdominal wall simulator for testing suprapubic urinary catheters.

    PubMed

    Coveney, V A; Gröver, D

    2001-08-01

    Urinary catheters (drainage tubes) are in widespread use. The most common type of long-term catheter is the Foley, which is made from natural or synthetic rubber. Foley catheters are passed into the bladder via the urethra or the suprapubic puncture channel (through the abdominal wall). A simulator for the abdominal wall has been developed to simulate aspects of the interaction between it and a suprapubic catheter. The simulator is based on a slab of ultrasoft elastomer with tensionable reinforcing polyamide filaments. The behaviour of the simulator has been compared with data published. A soft membrane (contact pressure) transducer (SMT) was used and novel instrumented 'tongs' for lateral indentation of the puncture track giving indentation stiffness. Slab materials were used with shear moduli of 0.1 and 0.021 MPa. Two filament-tensioning methods were used: by clamping to a winding mechanism and by weights. The combination of the softer slab material and tensioning by weights gave good conformity to physiological data; other combinations did not. PMID:11556670

  16. 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

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

    PubMed

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

    2015-04-15

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

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

    PubMed

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

    1996-03-01

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

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

    PubMed

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

    2016-06-01

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

  20. Biometric estimation of chest wall thickness of females

    SciTech Connect

    Berger, C.D.; Lane, B.H.

    1985-09-01

    Optimal use of whole-body counting data to estimate pulmonary deposition of many of the actinides is dependent upon accurate measurement of the thickness of the chest wall because of severe attenuation of low-energy x rays and photons associated with the decay of these radionuclides. An algorithm for estimation of female chest wall thicknesses, verified by real-time ultrasonic measurements, has been derived based on the correlation of measured chest wall thickness and other common biometric quantities. Use of this algorithm will reduce the error generally associated with estimation of internal actinide deposition previously resulting from assuming an average chest wall thickness for all female subjects.

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

    PubMed

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

    2008-02-01

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

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

    PubMed

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

    2016-02-01

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

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

    PubMed Central

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

    2013-01-01

    Background: The diagnosis of abdominal wall endometrioma (AWE) is often confused with other surgical conditions. Certain factors relating to knowledge of the clinical history of the disease make correct diagnosis and treatment difficult. Aims: To present the clinical findings and ultrasonographic (US) features of AWE with special emphasis on size-related features. Study Design: This study reviewed abdominal wall endometriomas during a 2-year period in the Radiology Department of Sifa University Hospital, Izmir. Methods: Eleven women (mean age 32.6 years) with 12 scar endometriomas (mean diameter 29.2 mm) were consecutively evaluated by US and Colour Doppler examination (CDUS) prior to surgery. Lesions were grouped into large (≥3 cm) and small nodules. Vascularisation was classified as location (central, peripheral and mixed) and severity (absent, moderately vascular and hypervascular). In each patient, the nature of pain (absent, cyclic: associated with menstruation and continuous), historical and clinical data were documented. Four patients underwent Magnetic Resonance Imaging and their findings were presented. Fisher’s exact test, χ2 test for categorical data and the unpaired T-test for continuous variables were used for statistical analysis. Results: In all the women, US of the AWE showed the presence of a solid hypoechoic mass (less echogenic than the surrounding hyperechoic fat) within the abdominal wall. There was a significant correlation between AWE sizes with repeated caesareans and the mean time between the last operation and admission to hospital (p<0.05). Large endometriomas showed increased central vascularity (p<0.05). Cyclic pain was more frequent in small lesions, whereas continuous pain was more commonly found in patients with larger lesions (p<0.05). Conclusion: AWE is often misdiagnosed clinically because endometriosis may occur years after the caesarean section, the pain is often non-cyclic in nature, and there is not always a palpable tender mass. The sonographic and Doppler findings, along with proper correlation with clinical data, may substantially contribute to the correct diagnosis of endometrioma. PMID:25207093

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

    PubMed

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

    2016-05-01

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

  5. 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.

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

    PubMed

    Chen, Shuang

    2015-11-25

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

  7. Myocardium wall thickness transducer and measuring method

    NASA Technical Reports Server (NTRS)

    Feldstein, C.; Lewis, G. W.; Silver, R. H.; Culler, V. H. (Inventor)

    1976-01-01

    A miniature transducer for measuring changes of thickness of the myocardium is described. The device is easily implantable without traumatizing the subject, without affecting the normal muscle behavior, and is removable and implantable at a different muscle location. Operating features of the device are described.

  8. Contribution of the skin, rectus abdominis and their sheaths to the structural response of the abdominal wall ex vivo.

    PubMed

    Tran, D; Mitton, D; Voirin, D; Turquier, F; Beillas, P

    2014-09-22

    A better understanding of the abdominal wall biomechanics could help designing new treatments for incisional hernia. In the current study, an experimental protocol was developed to evaluate the contributions of the abdominal wall components to the structural response of the anterior part of the abdominal wall. The specimens underwent 3 dissections (removal of (1) skin and subcutaneous fat, (2) anterior rectus sheath, (3) rectus abdominis muscles). After each dissection, they were subjected to air pressure up to 3 kPa. Ultrasound images and associated elastographic maps were collected at 0, 2 and 3 kPa in the intact state and strains on the internal surface were calculated using stereo-correlation in all states. Strains on the rectus abdominis and linea alba were analyzed. After the dissection of the anterior sheath of the rectus abdominis, longitudinal strain was found significantly different on the linea alba (5% at 3 kPa) and on the rectus abdominis area (11% at 3 kPa). The current results highlight the importance of the rectus sheath in the structural response of the anterior part of the abdominal wall ex vivo. Geometrical characteristics such as thicknesses and radii of curvature and mechanical properties (shear modulus of the rectus abdominis, e.g. at 0 pressure the average value is 14 kPa) were provided in order to facilitate future modeling efforts. PMID:25065730

  9. Abdominal wall closure after selective aponeurotic incision and undermining.

    PubMed

    Nahas, F X; Ishida, J; Gemperli, R; Ferreira, M C

    1998-12-01

    The tension required to pull the anterior and the posterior rectus sheaths toward the midline was studied in 20 fresh cadavers at two levels: 3 cm above and 2 cm below the umbilicus. The quotient of the force used to mobilize the aponeurotic site to the midline and its resulting displacement was called the traction index. These indices were compared in three situations: (1) prior to any aponeurotic undermining, (2) after the incision of the anterior rectus sheath and the undermining of the rectus muscle from its posterior sheath, and (3) after additionally releasing and undermining the external oblique muscle. A significant decrease in aponeurotic resistance was observed after each dissection. The anterior sheath showed higher resistance to traction compared with the posterior sheath on both levels. No statistical difference was noted in the comparison of the values of the aponeurosis above and below the umbilicus. These results suggest that these procedures are effective in assisting in the closure of abdominal wall defects because these maneuvers decrease substantially the tension required for advancement of the aponeurotic edges. PMID:9869133

  10. Evaluation of Tube Wall Thickness of Feed Water Heater

    NASA Astrophysics Data System (ADS)

    Uchikura, Takahisa; Morisaki, Koichi; Hamada, Seiichi

    With regard to the high pressure (HP) feed water heater of thermal power plant at Tokyo Electric Power Company (TEPCO) sites, inspection of feed water (FW) tubes wall thickness are conducted whenever required such that frequent tube leak occurs. As a standard inspection methodology, FW heater is disassembled during planned outage, tube wall thickness is measured by the ultrasonic pulse techique (UT), then plugs are installed at the both ends of FW tube if its measured wall thickness is found below calculated threshold. However, the root causes of wall thinning of FW tube are various such as erosion and corrosion, based on wall thinning condition, the above threshold is not applied but utilizing the other technically well-grounded evaluation method is sometimes more rational. Therefore, TEPCO classified wall-thinning condition based on inspection data and established technically well-grounded and rational evaluation methodologies of FW tube wall thickness to suite each wall thinning condition. Moreover, with recent improvement of inspection technique, technology enabled faster, larger amount, and more accurate data acquisition, TEPCO has developed the systematized evaluation methodology that can transact data acquisition and evaluation simultaneously. This article introduces the logic of evaluation methods and examined algorithms to make them systematized.

  11. Multifusion-induced wall-super-thick giant multilamellar vesicles.

    PubMed

    Yao, Wei; Qian, Hanqing; Zhang, Jialiang; Wu, Wei; Jiang, Xiqun

    2012-07-18

    A polymeric multivesicular system was created by hydrating a film. This system underwent multifusion events and eventually evolved into giant multilamellar vesicles with extremely thick walls. The semi-permeable wall and large size make these vesicles suitable for encapsulating living cells. PMID:22684038

  12. An analytic description of thick-wall bubbles

    SciTech Connect

    Hong, Jooyoo.

    1992-01-01

    A new approximation scheme to the false-vacuum decay is suggested. In this scheme the bounce solutions can be obtained in an explicit and analytic way even for thick-wall bubbles. The result is compared with Coleman's thin-wall description, which shows that is nicely comprises the result of the latter prescription. Some applications are also discussed.

  13. An analytic description of thick-wall bubbles

    SciTech Connect

    Hong, Jooyoo

    1992-08-01

    A new approximation scheme to the false-vacuum decay is suggested. In this scheme the bounce solutions can be obtained in an explicit and analytic way even for thick-wall bubbles. The result is compared with Coleman`s thin-wall description, which shows that is nicely comprises the result of the latter prescription. Some applications are also discussed.

  14. Effects of inspiratory muscle training on balance ability and abdominal muscle thickness in chronic stroke patients.

    PubMed

    Oh, Dongha; Kim, Gayeong; Lee, Wanhee; Shin, Mary Myong Sook

    2016-01-01

    [Purpose] This study evaluated the effects of inspiratory muscle training on pulmonary function, deep abdominal muscle thickness, and balance ability in stroke patients. [Subjects] Twenty-three stroke patients were randomly allocated to an experimental (n = 11) or control group (n = 12). [Methods] The experimental group received inspiratory muscle training-based abdominal muscle strengthening with conventional physical therapy; the control group received standard abdominal muscle strengthening with conventional physical therapy. Treatment was conducted 20 minutes per day, 3 times per week for 6 weeks. Pulmonary function testing was performed using an electronic spirometer. Deep abdominal muscle thickness was measured by ultrasonography. Balance was measured using the Berg balance scale. [Results] Forced vital capacity, forced expiratory volume in 1 second, deep abdominal muscle thickness, and Berg balance scale scores were significantly improved in the experimental group than in the control group. [Conclusion] Abdominal muscle strengthening accompanied by inspiratory muscle training is recommended to improve pulmonary function in stroke patients, and may also be used as a practical adjunct to conventional physical therapy. PMID:26957739

  15. Effects of inspiratory muscle training on balance ability and abdominal muscle thickness in chronic stroke patients

    PubMed Central

    Oh, Dongha; Kim, Gayeong; Lee, Wanhee; Shin, Mary Myong Sook

    2016-01-01

    [Purpose] This study evaluated the effects of inspiratory muscle training on pulmonary function, deep abdominal muscle thickness, and balance ability in stroke patients. [Subjects] Twenty-three stroke patients were randomly allocated to an experimental (n = 11) or control group (n = 12). [Methods] The experimental group received inspiratory muscle training-based abdominal muscle strengthening with conventional physical therapy; the control group received standard abdominal muscle strengthening with conventional physical therapy. Treatment was conducted 20 minutes per day, 3 times per week for 6 weeks. Pulmonary function testing was performed using an electronic spirometer. Deep abdominal muscle thickness was measured by ultrasonography. Balance was measured using the Berg balance scale. [Results] Forced vital capacity, forced expiratory volume in 1 second, deep abdominal muscle thickness, and Berg balance scale scores were significantly improved in the experimental group than in the control group. [Conclusion] Abdominal muscle strengthening accompanied by inspiratory muscle training is recommended to improve pulmonary function in stroke patients, and may also be used as a practical adjunct to conventional physical therapy. PMID:26957739

  16. The effects of dynamic exercise utilizing PNF patterns on abdominal muscle thickness in healthy adults

    PubMed Central

    Gong, Wontae

    2015-01-01

    [Purpose] The purpose of this study is to examine the effects of dynamic exercise utilizing the PNF (proprioceptor neuromuscular facilitation) patterns accompanied by abdominal drawing-in exercises on abdominal muscle thickness in healthy adults. [Subjects] The total number of subjects was 30;15 were randomly placed in the training group (TG), and the remaining 15 made up the control group (CG). [Methods] The subjects in the TG conducted 3–5 sets of dynamic exercises utilizing the PNF patterns each day, 3 times a week for 6 weeks. The thickness of the abdominal muscles was measured by ultrasonography. [Results] When the TG’s abdominal muscle thickness pre-test and post-test were compared in this study, there was a statistical significance in all of the external obliquus abdominis (Eo), the internal obliquus abdominis (Io), and the transversus abdominis (Tra). [Conclusion] Dynamic exercise utilizing the PNF patterns increased the thickness of the abdominal muscles that are the basis of trunk stabilization. PMID:26180351

  17. Bladder wall thickness mapping for magnetic resonance cystography

    NASA Astrophysics Data System (ADS)

    Zhao, Yang; Liang, Zhengrong; Zhu, Hongbin; Han, Hao; Duan, Chaijie; Yan, Zengmin; Lu, Hongbing; Gu, Xianfeng

    2013-08-01

    Clinical studies have shown evidence that the bladder wall thickness is an effective biomarker for bladder abnormalities. Clinical optical cystoscopy, the current gold standard, cannot show the wall thickness. The use of ultrasound by experts may generate some local thickness information, but the information is limited in field-of-view and is user dependent. Recent advances in magnetic resonance (MR) imaging technologies lead MR-based virtual cystoscopy or MR cystography toward a potential alternative to map the wall thickness for the entire bladder. From a high-resolution structural MR volumetric image of the abdomen, a reasonable segmentation of the inner and outer borders of the bladder wall can be achievable. Starting from here, this paper reviews the limitation of a previous distance field-based approach of measuring the thickness between the two borders and then provides a solution to overcome the limitation by an electric field-based strategy. In addition, this paper further investigates a surface-fitting strategy to minimize the discretization errors on the voxel-like borders and facilitate the thickness mapping on the three-dimensional patient-specific bladder model. The presented thickness calculation and mapping were tested on both phantom and human subject datasets. The results are preliminary but very promising with a noticeable improvement over the previous distance field-based approach.

  18. Occlusion-free Blood Flow Animation with Wall Thickness Visualization.

    PubMed

    Lawonn, Kai; Glaßer, Sylvia; Vilanova, Anna; Preim, Bernhard; Isenberg, Tobias

    2016-01-01

    We present the first visualization tool that combines pathlines from blood flow and wall thickness information. Our method uses illustrative techniques to provide occlusion-free visualization of the flow. We thus offer medical researchers an effective visual analysis tool for aneurysm treatment risk assessment. Such aneurysms bear a high risk of rupture and significant treatment-related risks. Therefore, to get a fully informed decision it is essential to both investigate the vessel morphology and the hemodynamic data. Ongoing research emphasizes the importance of analyzing the wall thickness in risk assessment. Our combination of blood flow visualization and wall thickness representation is a significant improvement for the exploration and analysis of aneurysms. As all presented information is spatially intertwined, occlusion problems occur. We solve these occlusion problems by dynamic cutaway surfaces. We combine this approach with a glyph-based blood flow representation and a visual mapping of wall thickness onto the vessel surface. We developed a GPU-based implementation of our visualizations which facilitates wall thickness analysis through real-time rendering and flexible interactive data exploration mechanisms. We designed our techniques in collaboration with domain experts, and we provide details about the evaluation of the technique and tool. PMID:26529724

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

    PubMed Central

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

    2015-01-01

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

  20. Absolute neutron dosimetry: Effects of ionization chamber wall thickness

    SciTech Connect

    Ten Haken, R.K.; Awschalom, M.; Rosenberg, I.

    1985-01-01

    To assess the effect of ionization chamber wall thickness on absolute neutron absorbed dose determinations, measurements were made of the charge collected by an A-150 tissue-equivalent plastic ionization chamber irradiated by a p(66)Be(49) neutron therapy beam as a function of chamber wall thickness both in air and in four different media: tissue-equivalent solution, water, motor oil, and glycerin. Wall thicknesses ranged from 1 to 31 mm, where isolation of the chamber gas volume from protons originating outside the chamber wall was assured. The in-air measurements compare favorably with earlier buildup measurements performed with an A-150 extrapolation chamber in an A-150 phantom. The in-phantom results may be explained if the effect of charged particles reaching the gas volume from the medium and the wall as well as the differences in neutron attenuation by the wall and the medium displaced by the wall are taken into account. The errors in absolute absorbed dose determination caused by ignoring the above processes are assessed.

  1. Severe cellulitis and abdominal wall emphysema following laparoscopic colonic surgery: A case report.

    PubMed

    Tanaka, Ryo; Kameyama, Hitoshi; Chida, Tadasu; Kanda, Tatsuo; Kano, Yosuke; Ichikawa, Hiroshi; Hanyu, Takaaki; Ishikawa, Takashi; Kosugi, Shin-Ichi; Wakai, Toshifumi

    2015-05-01

    Abdominal wall emphysema is a common complication of laparoscopic surgery. This condition is usually harmless; however, if an infection occurs, it can develop into a serious condition such as necrotizing fasciitis. We report a case of a 51-year-old woman suffering from severe cellulitis that spread from an area of abdominal wall emphysema after laparoscopic surgery for sigmoid colon cancer. Recognizing this complication, early diagnosis, and prompt treatment are cornerstones for successful management of this potentially fatal disease. PMID:25913586

  2. [Meshed implants of polyvinylidene fluoride in treatment of abdominal wall hernias].

    PubMed

    Sedov, V M; Gostevsko?, A A; Tarbaev, S D; Gorelov, A S; Chulkhovin, A B; Nuftullina, G M; Zhukovski?, V A

    2008-01-01

    The authors analyze the results of experimental and clinical investigations for comparative studying a new meshed implant of polyvinylidene fluoride as an endoprosthesis of the anterior abdominal wall with postoperative hernias. It was shown that the polyvinylidene fluoride prosthesis is a good alternative of polypropylene prosthesis. Its physico-chemical properties allow reliable prostheses of the abdominal wall, and its biological compatibility is higher as compared with polypropylene prosthesis. PMID:18522179

  3. Gear-shift lever having variable thickness walls

    SciTech Connect

    Tanaka, T.

    1988-01-03

    A one-piece elongated tubular transmission gear shift lever, is described comprising a tubular connector part at a first end of the gear shift lever, whereby the tubular connector part is adapted to be secured to a pivot means; a spherical part extending from the connector part, the connector part and the spherical part having a first wall thickness; a cylindrical part extending from the spherical part in a direction opposite the tubular connector part, the cylindrical part having a second wall thickness less than the first wall thickness; a tapered part extending from the cylindrical part; and a threaded part extending from the tapered part, the threaded part formed at a second end of the gear shift lever opposite the first end, whereby a gear shift knob may be attached.

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

    PubMed Central

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

    2014-01-01

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

  5. Abdominal wall pain in obese women: frequently missed and easily treated

    PubMed Central

    Mishriki, Yehia Yousri

    2009-01-01

    Chronic abdominal pain is a common symptom with an extensive differential diagnosis. The work-up is frequently costly, yet many patients elude definitive diagnosis. We describe 12 obese women with long-standing abdominal pain, many of whom eluded diagnosis but who met criteria for abdominal wall pain. Each patient underwent a focused history and physical examination which included checking for Carnett’s sign and performing a “pinch test”. All patients had positive Carnett’s sign and pinch tests. An injection of local anaesthetic, with or without corticosteroid, completely relieved the pain within 10 min. Of the six patients seen in follow-up, four remained pain free and two responded to a second injection of local anaesthetic. Abdominal wall pain is an under-appreciated cause of chronic abdominal pain. Diagnosis is often straightforward and treatment with a local injection of anaesthetic is both diagnostic and curative. PMID:21686788

  6. Evaluation of scoring accuracy for airway wall thickness

    NASA Astrophysics Data System (ADS)

    Odry, Benjamin L.; Kiraly, Atilla P.; Novak, Carol L.; Naidich, David P.; Ko, Jane P.; Godoy, Myrna C. B.

    2009-02-01

    Bronchial wall thickening is commonly observed in airway diseases. One method often used to quantitatively evaluate wall thickening in CT images is to estimate the ratio of the bronchial wall to the accompanying artery, or BWA ratio, and then assign a severity score based on the ratio. Assessment by visual inspection is unfortunately limited to airways perpendicular or parallel to the scanning plane. With high-resolution images from multi-detector CT scanners, it becomes possible to assess airways in any orientation. We selected CT scans from 20 patients with mild to severe COPD. A computer system automatically segmented each bronchial tree and measured the bronchial wall thicknesses. Next, neighboring arteries were detected and measured to determine BWA ratios. A score characterizing the extent and severity of wall thickening within each lobe was computed according to recommendations by Sheehan et al [1]. Two experienced radiologists independently scored wall thickening using visual assessment. Spearman's rank correlation showed a non-significant negative correlation (r=-0.1) between the computer and the reader average (p=0.4), while the correlation between readers was significant at r=0.65 (p=0.001). We subsequently identified 24 lobes with high discrepancies between visual and automated scoring. The readers re-examined those lobes and measured wall thickness using electronic calipers on perpendicular cross sections, rather than visual assessment. Using this more objective standard of wall thickness, the reader estimates of wall thickening increased to reach a significant positive correlation with automated scoring of r=0.65 (p=0.001). These results indicate that subjectivity is an important problem with visual evaluation, and that visual inspection may frequently underestimate disease extent and severity. Given that a manual evaluation of all airways is infeasible in routine clinical practice, we argue that automated methods should be developed and utilized.

  7. Stability of resistive wall modes with plasma rotation and thick wall in ITER scenario

    NASA Astrophysics Data System (ADS)

    Zheng, L. J.; Kotschenreuther, M.; Chu, M.; Chance, M.; Turnbull, A.

    2004-11-01

    The rotation effect on resistive wall modes (RWMs) is examined for realistically shaped, high-beta tokamak equilibria, including reactor relevant cases with low mach number M and realistic thick walls. For low M, Stabilization of RWMs arises from unusually thin inertial layers. The investigation employs the newly developed adaptive eigenvalue code (AEGIS: Adaptive EiGenfunction Independent Solution), which describes both low and high n modes and is in good agreement with GATO in the benchmark studies. AEGIS is unique in using adaptive methods to resolve such inertial layers with low mach number rotation. This feature is even more desirable for transport barrier cases. Additionally, ITER and reactors have thick conducting walls ( ˜.5-1 m) which are not well modeled as a thin shell. Such thick walls are considered here, including semi-analytical approximations to account for the toroidally segmented nature of real walls.

  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 was <10 degrees , cranial/caudal or medial/lateral transducer tilting was <10 degrees and 8 degrees , respectively and inward/outward motion was <8 mm. These findings provide guidance on acceptable amounts of transducer motion relative to the pelvis when generating measurements of TrA thickness and bladder base position. Future sonographic studies and clinical assessment investigating these parameters could take these findings into account to improve imaging technique reliability. PMID:19699027

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

    PubMed

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

    2016-02-01

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

  10. Studying the visceral physiology of tadpoles through their naturally transparent abdominal walls

    NASA Astrophysics Data System (ADS)

    Naitoh, T.; Yamashita, M.; Wassersug, R. J.

    2003-10-01

    We propose using anuran tadpoles with naturally transparent abdominal skin to study the visceral physiology of amphibian larvae under microgravity. The transparency of the abdominal wall in certain tadpoles enables one to evaluate the basal physiological state and temporal changes in viscera from their movements without any invasive treatment. In order to validate our experimental design, the intestinal motility and heart rate of Rhacophorus tadpoles were examined as indices of physiological responses to stepwise changes in temperature.

  11. Thick domain walls in AdS black hole spacetimes

    SciTech Connect

    Moderski, Rafal; Rogatko, Marek

    2006-08-15

    Equations of motion for a real self-gravitating scalar field in the background of a black hole with negative cosmological constant were solved numerically. We obtain a sequence of static axisymmetric solutions representing thick domain wall cosmological black hole systems, depending on the mass of black hole, cosmological parameter and the parameter binding black hole mass with the width of the domain wall. For the case of extremal cosmological black hole the expulsion of scalar field from the black hole strongly depends on it.

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

    SciTech Connect

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

    2013-12-15

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

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

    PubMed Central

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

    2013-01-01

    Purpose: The treatment of ventral hernias (VH) has been a challenging problem for medical care. Repair of these hernias is fraught with failure; recurrence rates ranging from 24% to 43% have been reported, even with the use of biocompatible mesh. Currently, computed tomography (CT) is used to guide intervention through expert, but qualitative, clinical judgments, notably, quantitative metrics based on image-processing are not used. The authors propose that image segmentation methods to capture the three-dimensional structure of the abdominal wall and its abnormalities will provide a foundation on which to measure geometric properties of hernias and surrounding tissues and, therefore, to optimize intervention. Methods: In this study with 20 clinically acquired CT scans on postoperative patients, the authors demonstrated a novel approach to geometric classification of the abdominal. The authors’ approach uses a texture analysis based on Gabor filters to extract feature vectors and follows a fuzzy c-means clustering method to estimate voxelwise probability memberships for eight clusters. The memberships estimated from the texture analysis are helpful to identify anatomical structures with inhomogeneous intensities. The membership was used to guide the level set evolution, as well as to derive an initial start close to the abdominal wall. Results: Segmentation results on abdominal walls were both quantitatively and qualitatively validated with surface errors based on manually labeled ground truth. Using texture, mean surface errors for the outer surface of the abdominal wall were less than 2 mm, with 91% of the outer surface less than 5 mm away from the manual tracings; errors were significantly greater (2–5 mm) for methods that did not use the texture. Conclusions: The authors’ approach establishes a baseline for characterizing the abdominal wall for improving VH care. Inherent texture patterns in CT scans are helpful to the tissue classification, and texture analysis can improve the level set segmentation around the abdominal region. PMID:24320512

  14. Noninvasive Stiffness Sensing of Ventricular Wall Based on a Thick-walled Cylinder Model

    NASA Astrophysics Data System (ADS)

    Higashimori, Mitsuru; Ojio, Takeshi; Takeda, Yasuharu; Sakata, Yasushi; Yamamoto, Kazuhiro; Kaneko, Makoto

    This paper discusses a concept of a noninvasive sensing method that can estimate a left ventricular wall stiffness towards a medical diagnosis. Focusing on not only the strain of ventricular wall but also the displacements of epicardium during diastole of heart beat, we propose an index of ventricular wall stiffness based on a thick-walled cylinder model. Applying the proposed method to the echocardiography, we show statistical results where normal and HFpEF (Heart Failure with preserved Ejection Fraction) can be separated towards a medical diagnosis.

  15. Multilayer injection moulding of thick-walled optical plastics parts

    NASA Astrophysics Data System (ADS)

    Hopmann, Ch.; Neuss, A.; Weber, M.; Walach, P.

    2014-05-01

    Optical components are often thick-walled. The cycle time of precise polymer optics with a wall thickness of more than 20 mm exceeds several minutes. The multilayer injection moulding or compression moulding lowers the cycle time and increases the quality of the moulded parts. For the production of multilayer moulded lenses the mould design plays an important role. An innovative mould concept is presented with the possiblity to produce double or triple layer lenses. To ensure the quality and the endurance of multilayer moulded optical components in their applications, the cohesion in the interface is important. Tensile shear tests show the ability of multilayer moulded parts with high cohesion values for optical applications.

  16. Chest wall thickness measurements for enriched uranium: An alternative approach

    SciTech Connect

    Kramer, G.H.; Puscalau, M.

    1994-05-01

    Human Monitoring Laboratory has developed a technique to determine the chest wall thickness of an individual using information from the spectrum produced by internally deposited radionuclides. The technique has been investigated both theoretically and practically using phoswich detectors and the Lawrence Livermore Torso Phantom. The phantom was used with lung sets containing homogeneously distributed 93% enriched uranium, 20% enriched uranium, natural uranium, and {sup 241}Am. It was found that a 3-cm chest wall thickness can be estimated to within 9% when measuring 93% enriched uranium. The technique does not work for the latter two radionuclides because of an insufficient separation in the photon energies and poor resolution of the phoswich detectors. The technique is only of value for activity levels limit. 5 refs., 3 figs., 1 tab.

  17. Evaluation of UT Wall Thickness Measurements and Measurement Methodology

    SciTech Connect

    Weier, Dennis R.; Pardini, Allan F.

    2007-10-01

    CH2M HILL has requested that PNNL examine the ultrasonic methodology utilized in the inspection of the Hanford double shell waste tanks. Specifically, PNNL is to evaluate the UT process variability and capability to detect changes in wall thickness and to document the UT operator's techniques and methodology in the determination of the reported minimum and average UT data and how it compares to the raw (unanalyzed) UT data.

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

    PubMed Central

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

    2013-01-01

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

  19. Polymicrobial abdominal wall necrotizing fasciitis after cesarean section.

    PubMed

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

    2012-01-01

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

  20. Mechanical response of human abdominal walls ex vivo: Effect of an incisional hernia and a mesh repair.

    PubMed

    Podwojewski, F; Otténio, M; Beillas, P; Guérin, G; Turquier, F; Mitton, D

    2014-10-01

    The design of meshes for the treatment of incisional hernias could benefit from better knowledge of the mechanical response of the abdominal wall and how this response is affected by the implant. The aim of this study was to characterise the mechanical behaviour of the human abdominal wall. Abdominal walls were tested ex vivo in three states: intact, after creation of a defect simulating an incisional hernia, and after reparation with a mesh implanted intraperitonally. For each state, the abdominal wall was subjected to air pressure loading. Local strain fields were determined using digital image correlation techniques. The strain fields on the internal and external surfaces of the abdominal wall exhibited different patterns. The strain patterns on the internal surface appeared to be related to the underlying anatomy of the abdominal wall. Higher strains were observed along the linea alba than along the perpendicular direction. Under pressure loading, the created incision increased the strain of the abdominal wall compared to the intact state in 5 cases of a total 6. In addition, the mesh repair decreased the strains of the abdominal wall compared to the incised state in 4 cases of 6. These results suggest that the intraperitoneal mesh restores at least partially the mechanical behaviour of the wall and provides quantification of the effects on the strains in various regions. PMID:25051150

  1. Urinary bladder herniation through a caudoventral abdominal wall defect in a mature cat

    PubMed Central

    Neville-Towle, Jack; Sakals, Sherisse

    2015-01-01

    A 16-year-old spayed female domestic shorthair cat with no history of trauma was presented to the Western College of Veterinary Medicine for assessment of urinary incontinence. Diagnostic investigation revealed herniation of the urinary bladder through a caudoventral abdominal wall defect. Clinical signs resolved after surgical reduction of the bladder. PMID:26347198

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

    PubMed

    Kritsaneepaiboon, Supika; Sangkhathat, Surasak; Mitarnun, Winyou

    2015-07-01

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

  3. Abdominal wall Actinomyces abscess associated with an intrauterine device. A case report.

    PubMed

    Pearlman, M; Frantz, A C; Floyd, W S; Faro, S

    1991-05-01

    An abdominal wall Actinomyces abscess occurred in a woman with an intrauterine device. Contributing factors were local trauma, spread from surrounding colonized body sites and symbiotic growth of other anaerobes. The diagnosis was based on the histologic finding of the sulfur granule. Special studies may be needed to distinguish this condition from other, similar ones (Nocardia, botryomycosis). PMID:1829483

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

    PubMed Central

    Kritsaneepaiboon, Supika; Sangkhathat, Surasak; Mitarnun, Winyou

    2015-01-01

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

  5. Functional and morphological evaluation of different polypropylene-mesh modifications for abdominal wall repair.

    PubMed

    Klosterhalfen, B; Klinge, U; Schumpelick, V

    1998-12-01

    Modern surgical hernia repair depends increasingly on synthetic meshes for the reconstruction of the abdominal wall. Despite the undisputed advantages of the polypropylene (PP) meshes currently available (Marlex, Prolene), reports of complications after implantation are increasing. Although, serious complications such as perforation and fistula formation are rare, minor and local complaints such as seromas, misfeelings and a decreased abdominal wall mobility are observed in about one-half of the patients. In regard to the exaggerated strength of the currently available mesh modifications a reduction of the material should improve the integration of the meshes into the artificial abdominal wall. In the present study, the commercially available basic mesh Prolene has been compared to two newly constructed PP-mesh modifications with reduced amounts of PP. The modifications have gradually been adopted to the physiological requirements of abdominal wall stability and mobility by reducing the amount of PP to 64% (E-BLUE) and 24% (variant A) of the Prolene mesh (developed by ETHICON, Norderstedt, Germany). All PP-mesh variants have been implanted in a rat model and studied by 3D-photogrammetry, tensiometry, light- and electron microscopy, as well as morphometry over implantation intervals of 3, 7, 14, 21 and 90 days. The data show that current constructions of PP-meshes are oversized and definitely restrict abdominal wall mobility in the present model. Sufficient stability of the artificial abdominal wall is even guaranteed by PP-mesh modifications with a reduction of PP-quantity to about 25% of the Prolene mesh. The degree of fibrosis directly correlated with abdominal wall restriction, whereas the formation of connective tissue in the interface PP-fibre/host-issue depends on the amount and activity of the inflammatory reaction. The quantity and quality of inflammation, again, directly relies to the amount of PP and to the surface area in contact with the recipient tissues. Altogether, the present study suggests that a modification of the PP-meshes could be helpful to prevent major and minor complications of surgical PP-meshes. PMID:9884036

  6. Haemostatic factors and intraluminal thrombus thickness in abdominal aortic aneurysm. Is secondary fibrinolysis relevant?

    PubMed

    Siennicka, A; Drozdzynska, M; Chelstowski, K; Cnotliwy, M; Jastrzebska, M

    2013-06-01

    Many circulating haemostatic markers have been investigated in relation to the abdominal aortic aneurysm (AAA) size, growth as well as intraluminal thrombus (ILT) size. However, the results of these studies seem to be uncertain and inconsistent. The first aim of the present study was to compare the haemostatic parameters of fibrinolysis and some of thrombotic markers in patients with AAA and controls. We also examined the relationship between those parameters and both maximum aneurysm diameter and intraluminal thrombus thickness. Tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1), fibrinogen (Fb), D-dimer, prothrombin fragments 1 and 2 (F1+2), thromboxane B2 (TXB2) and lipids profile were measured in 36 patients with AAA and 30 controls. The mean maximum aortic diameter in patients with the AAA was 59±12 mm (range 42-100). The mean ILT thickness was 32±10 mm (range 8-56). Among haemostatic factors, t-PA and D-dimer levels, but not PAI-1, were significantly higher in subjects with the AAA. There was a strong positive correlation between thickness of intraluminal thrombus and maximum aneurysm size (r=0.69, p<0.0001), and the negative relationship between t-PA and ILT thickness (r= -0.53, p=0.001) as well as aneurysm diameter (r= -0.38, p=0.023). Higher plasma concentrations of t-PA and D-dimer support the hypothesis that the secondary fibrinolysis plays an important role in the pathogenesis of the aortic abdominal aneurysm formation. In addition, the negative correlation between t-PA plasma level and ILT thickness suggests that thrombotic/fibrinolysis imbalance may favour accelerated formation of intraluminal thrombus and possibly aneurysm progression. PMID:23959729

  7. Terahertz inline wall thickness monitoring system for plastic pipe extrusion

    SciTech Connect

    Hauck, J. E-mail: d.stich@skz.de E-mail: m.bastian@skz.de Stich, D. E-mail: d.stich@skz.de E-mail: m.bastian@skz.de Heidemeyer, P. E-mail: d.stich@skz.de E-mail: m.bastian@skz.de Bastian, M. E-mail: d.stich@skz.de E-mail: m.bastian@skz.de Hochrein, T. E-mail: d.stich@skz.de E-mail: m.bastian@skz.de

    2014-05-15

    Conventional and commercially available inline wall thickness monitoring systems for pipe extrusion are usually based on ultrasonic or x-ray technology. Disadvantages of ultrasonic systems are the usual need of water as a coupling media and the high damping in thick walled or foamed pipes. For x-ray systems special safety requirements have to be taken into account because of the ionizing radiation. The terahertz (THz) technology offers a novel approach to solve these problems. THz waves have many properties which are suitable for the non-destructive testing of plastics. The absorption of electrical isolators is typically very low and the radiation is non-ionizing in comparison to x-rays. Through the electromagnetic origin of the THz waves they can be used for contact free measurements. Foams show a much lower absorption in contrast to acoustic waves. The developed system uses THz pulses which are generated by stimulating photoconductive switches with femtosecond laser pulses. The time of flight of THz pulses can be determined with a resolution in the magnitude of several ten femtoseconds. Hence the thickness of an object like plastic pipes can be determined with a high accuracy by measuring the time delay between two reflections on materials interfaces e.g. at the pipe's inner and outer surface, similar to the ultrasonic technique. Knowing the refractive index of the sample the absolute layer thickness from the transit time difference can be calculated easily. This method in principle also allows the measurement of multilayer systems and the characterization of foamed pipes.

  8. Terahertz inline wall thickness monitoring system for plastic pipe extrusion

    NASA Astrophysics Data System (ADS)

    Hauck, J.; Stich, D.; Heidemeyer, P.; Bastian, M.; Hochrein, T.

    2014-05-01

    Conventional and commercially available inline wall thickness monitoring systems for pipe extrusion are usually based on ultrasonic or x-ray technology. Disadvantages of ultrasonic systems are the usual need of water as a coupling media and the high damping in thick walled or foamed pipes. For x-ray systems special safety requirements have to be taken into account because of the ionizing radiation. The terahertz (THz) technology offers a novel approach to solve these problems. THz waves have many properties which are suitable for the non-destructive testing of plastics. The absorption of electrical isolators is typically very low and the radiation is non-ionizing in comparison to x-rays. Through the electromagnetic origin of the THz waves they can be used for contact free measurements. Foams show a much lower absorption in contrast to acoustic waves. The developed system uses THz pulses which are generated by stimulating photoconductive switches with femtosecond laser pulses. The time of flight of THz pulses can be determined with a resolution in the magnitude of several ten femtoseconds. Hence the thickness of an object like plastic pipes can be determined with a high accuracy by measuring the time delay between two reflections on materials interfaces e.g. at the pipe's inner and outer surface, similar to the ultrasonic technique. Knowing the refractive index of the sample the absolute layer thickness from the transit time difference can be calculated easily. This method in principle also allows the measurement of multilayer systems and the characterization of foamed pipes.

  9. Thick-wall Kevlar 49/Epoxy pressure vessels

    SciTech Connect

    Guess, T.R.

    1984-01-01

    The feasibility of thick-wall composite vessels for very high pressure applications is demonstrated. Prototype vessels, in both spherical and cylindrical geometries, were designed, fabricated and burst tested. It is shown that experimental burst pressures are in excellent agreement with predicted values for burst pressures up to 60 ksi. Each unit consisted of a thin, seamless, copper liner with stainless steel fill stems and a filament-wound Kevlar 49/epoxy outer shell. Analysis of vessel performance accounted for liner thickness and yield strengths, composite thickness, mechanical properties and fiber volume fraction, and stress concentrations caused by the fill stem. Spherical vessels of three different sizes (inside diameters of 2.15 inches, 4.0 inches and 5.3 inches) with either 30 ksi or 60 ksi design burst pressure are discussed. Also, cylindrical vessels with identical liners but of two different composite thicknesses are described. These vessels achieved 50 ksi and 57 ksi burst pressures, respectively. In addition to the design considerations alluded to throughout the paper, the stress state in a thin metal liner during cyclic loading and the life prediction of composite vessels under sustained loading are discussed.

  10. Malignant mesothelioma presenting as a giant chest, abdominal and pelvic wall mass.

    PubMed

    Shao, Zhi-hong; Gao, Xiao-long; Yi, Xiang-hua; Wang, Pei-jun

    2011-01-01

    Malignant mesothelioma (MM) is a relatively rare carcinoma of the mesothelial cells, and it is usually located in the pleural or peritoneal cavity. Here we report on a unique case of MM that developed in the chest, abdominal and pelvic walls in a 77-year-old female patient. CT and MRI revealed mesothelioma that manifested as a giant mass in the right flank and bilateral pelvic walls. The diagnosis was confirmed by the pathology and immunohistochemistry. Though rare, accurate investigation of the radiological features of a body wall MM may help make an exact diagnosis. PMID:22043159

  11. Deep abdominal muscle thickness measured under sitting conditions during different stability tasks.

    PubMed

    Nagai, Hideyuki; Akasaka, Kiyokazu; Otsudo, Takahiro; Sawada, Yutaka; Okubo, Yu

    2016-03-01

    [Purpose] This study was conducted to investigate ultrasonically determined changes in the thickness of the transversus abdominis and internal oblique muscles during different sitting conditions. [Subjects and Methods] Twenty healthy men volunteered to participate in this study. Four different sitting conditions including (A) sitting, (B) sitting with left hip flexion, (C) sitting with an abdominal hollowing maneuver (AHM), and (D) sitting with an AHM and left hip flexion, were used. Subjective exercise difficulty was evaluated. [Results] Transversus abdominis and internal oblique muscle thicknesses significantly differed between conditions, with significantly greater thickness between positions from (A) to (D). Stability of the surface when sitting had no effect on the muscle thickness of the transversus abdominis. By contrast, sitting on an unstable surface caused an increase in muscle thickness of the internal oblique in each condition. The subjects reported progressively increasing difficulty in performing each exercise in a stable position from (A) to (D), while the difficulty in an unstable position was significantly different between (A) and (B), and between (C) and (D). [Conclusion] Our findings suggest that task (B) on a stable surface should be chosen for maximal activation of transversus abdominis without inducing overactivation of the internal oblique muscle. PMID:27134381

  12. Deep abdominal muscle thickness measured under sitting conditions during different stability tasks

    PubMed Central

    Nagai, Hideyuki; Akasaka, Kiyokazu; Otsudo, Takahiro; Sawada, Yutaka; Okubo, Yu

    2016-01-01

    [Purpose] This study was conducted to investigate ultrasonically determined changes in the thickness of the transversus abdominis and internal oblique muscles during different sitting conditions. [Subjects and Methods] Twenty healthy men volunteered to participate in this study. Four different sitting conditions including (A) sitting, (B) sitting with left hip flexion, (C) sitting with an abdominal hollowing maneuver (AHM), and (D) sitting with an AHM and left hip flexion, were used. Subjective exercise difficulty was evaluated. [Results] Transversus abdominis and internal oblique muscle thicknesses significantly differed between conditions, with significantly greater thickness between positions from (A) to (D). Stability of the surface when sitting had no effect on the muscle thickness of the transversus abdominis. By contrast, sitting on an unstable surface caused an increase in muscle thickness of the internal oblique in each condition. The subjects reported progressively increasing difficulty in performing each exercise in a stable position from (A) to (D), while the difficulty in an unstable position was significantly different between (A) and (B), and between (C) and (D). [Conclusion] Our findings suggest that task (B) on a stable surface should be chosen for maximal activation of transversus abdominis without inducing overactivation of the internal oblique muscle.

  13. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  14. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  15. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Nominal wall thickness (t) for steel pipe. 192.109 Section 192.109 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  16. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Nominal wall thickness (t) for steel pipe. 192.109... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.109 Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

  17. 49 CFR 192.109 - Nominal wall thickness (t) for steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Nominal wall thickness (t) for steel pipe. 192.109... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.109 Nominal wall thickness (t) for steel pipe. (a) If the nominal wall thickness for steel pipe is not...

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

    PubMed

    Basile, Francesco; Biondi, Antonio; Donati, Marcello

    2013-01-01

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

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

    PubMed

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

    2013-04-01

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

  20. [A necrotizing fasciitis of an abdominal wall after a cholecystectomy--a case report].

    PubMed

    Jandík, J; Vokůrka, J

    2009-01-01

    The authors present a case review of a patient with a life threatening infectious complication after a routine operation with an accent on urgent diagnosis and treatment. A sepsis with an extensive necrotizing anaerobic infection of the surgical wound with a destruction of abdominal wound developed in 48 hours after a cholecystectomia. The patient status required repeatedly an extensive necrectomy with a hospitalization on an intensive care unit with a necessity of an arteficial pulmonary ventilation and a circulation support. A resulting large defect of an abdominal wall was fully healed by using a vacuum sealing treatment and a dermoepidermal skin graft. PMID:19358467

  1. Lipedema complicated by lymphedema of the abdominal wall and lower limbs.

    PubMed

    Zelikovski, A; Haddad, M; Koren, A; Avrahami, R; Loewinger, J

    2000-06-01

    We describe a 52 year-old woman in whom lymphedema primarily of the abdominal wall was superimposed on lipedema resulting in an abdomen of enormous dimensions with marked impairment of ambulation. Treatment consisted of preoperative compression of the legs by an external pneumatic device (Lympha-Press) followed by excision of the lymphedematous abdominal fat pad in conjunction with "debulking" of the right leg. The patient illustrates the extremes of lipedema complicated by lymphedema and the technical difficulties associated with its management. PMID:10897469

  2. Abdominal fat thickness measurement using Focused Impedance Method (FIM) - phantom study

    NASA Astrophysics Data System (ADS)

    Haowlader, Salahuddin; Baig, Tanveer Noor; Siddique-e Rabbani, K.

    2010-04-01

    Abdominal fat thickness is a risk indicator of heart diseases, diabetes, etc., and its measurement is therefore important from the point of view of preventive care. Tetrapolar electrical impedance measurements (TPIM) could offer a simple and low cost alternative for such measurement compared to conventional techniques using CT scan and MRI, and has been tried by different groups. Focused Impedance Method (FIM) appears attractive as it can give localised information. An intuitive physical model was developed and experimental work was performed on a phantom designed to simulate abdominal subcutaneous fat layer in a body. TPIM measurements were performed with varying electrode separations. For small separations of current and potential electrodes, the measured impedance changed little, but started to decrease sharply beyond a certain separation, eventually diminishing gradually to negligible values. The finding could be explained using the intuitive physical model and gives an important practical information. TPIM and FIM may be useful for measurement of SFL thickness only if the electrode separations are within a certain specific range, and will fail to give reliable results if beyond this range. Further work, both analytical and experimental, are needed to establish this technique on a sound footing.

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-08-01

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2012-01-01

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

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

    PubMed

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

    2012-01-01

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

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

    PubMed Central

    Chong, Vincent; Ram, Rishi

    2015-01-01

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

  9. 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. PMID:19730929

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

    PubMed Central

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

    2015-01-01

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

  11. The logic behind thick, liquid-walled, fusion concepts

    SciTech Connect

    Moir, R.W.

    1994-04-15

    It may be possible to surround the region where fusion reactions are taking place with a neutronically thick liquid blanket which has penetrations that allow only a few tenths of a percent of the neutrons to leak out. Even these neutrons can be attenuated by adding an accurately placed liquid or solid near the target to shadow-shield the beam ports from line-of-sight neutrons. The logic of such designs are discussed and their evolution is described with examples applied to both magnetic and inertial fusion (HYLIFE-II). These designs with liquid protection are self healing when exposed to pulsed loading and have a number of advantages-over the usual designs with solid first walls. For example, the liquid-protected solid components will last the life of the plant, and therefore the capacity factor is estimated to be approximately 10% higher than for the non-liquid-walled blankets, because no blanket replacement shutdowns are required. The component replacement, operations, and maintenance costs might be half the usual value because no blanket change-out costs or accompanying facilities are required. These combined savings might lower the cost of electricity by 20%. Nuclear-grade construction should not be needed, largely because the liquid attenuates neutrons and results in less activation of materials. Upon decommissioning, the reactor materials should qualify for disposal by shallow burial even when constructed of ordinary 304 stainless steel. The need for a high-intensity 14-MeV neutron test facility to develop first-wall materials is avoided or greatly reduced, saving billions of development dollars. Flowing molten Li, the molten salt Flibe (Li{sub 2}BeF{sub 4}), and molten Li{sub l7}Pb{sub 83} have been considered. An advantage of molten salt is that it will not burn and has a low tritium solubility and therefore low tritium inventory.

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

    PubMed Central

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

    2016-01-01

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

  13. 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

  14. Evolution of the wall shear stresses during the progressive enlargement of symmetric abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Salsac, A.-V.; Sparks, S. R.; Chomaz, J.-M.; Lasheras, J. C.

    2006-08-01

    The changes in the evolution of the spatial and temporal distribution of the wall shear stresses (WSS) and gradients of wall shear stresses (GWSS) at different stages of the enlargement of an abdominal aortic aneurysm (AAA) are important in understanding the aetiology and progression of this vascular disease since they affect the wall structural integrity, primarily via the changes induced on the shape, functions and metabolism of the endothelial cells. Particle image velocimetry (PIV) measurements were performed in in vitro aneurysm models, while changing their geometric parameters systematically. It has been shown that, even at the very early stages of the disease, i.e. increase in the diameter ≤ 50%, the flow separates from the wall and a large vortex ring, usually followed by internal shear layers, is created. These lead to the generation of WSS that drastically differ in mean and fluctuating components from the healthy vessel. Inside the AAA, the mean WSS becomes negative along most of the aneurysmal wall and the magnitude of the WSS can be as low as 26% of the value in a healthy abdominal aorta.

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

    PubMed Central

    2012-01-01

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

  16. Relation between abdominal subcutaneous fat tissue thickness and inflammatory markers during pregnancy

    PubMed Central

    Köşüş, Aydın; Turhan, Nilgün

    2014-01-01

    Introduction Subcutaneous abdominal fat thickness (SCFT) is important for predisposition to metabolic and cardiovascular diseases. Our aim was to evaluate maternal SCFT and metabolic changes (such as insulin resistance and high inflammatory markers) during pregnancy. Material and methods A total of 92 pregnant women between 24–28 weeks of gestation were enrolled in the study. The SCFT was measured by ultrasonography and patients were divided into 2 groups according to thickness of maternal SCFT and body mass index (BMI). Groups were compared with each other for oral glucose loading test (OGL) results, and for haematological, biochemical and fetal biometric parameters. Results After analysis of frequency for SCFT, the most appropriate cut-off value for grouping patients was found to be 15 mm for SCFT. In 48 cases SCFT was over 15 mm. High C reactive protein (CRP) was found in 47.9% (23) of cases with SCFT over 15 mm. Serum haemoglobin A1c (HbA1c) level was significantly correlated with SCFT thickness. The most important factors for determination of OGL level were found to be serum HbA1c level, BMI and SCFT. In obese subjects (BMI ≥ 25 kg/m2), levels of inflammatory markers and SCFT thickness were higher. The CRP and γ-glutamyltransferase (GGT) levels were significantly correlated with BMI and SCFT. Conclusions High SCFT during pregnancy is associated with elevated inflammatory marker levels and HbA1c. Pregnant women with thicker SCFT may be susceptible to the development of metabolic complications of pregnancy, such as gestational diabetes mellitus (GDM) and hypertension, as well as risk of future metabolic and cardiovascular disease. PMID:25276159

  17. A rare case of chronic traumatic diaphragmatic hernia requiring complex abdominal wall reconstruction

    PubMed Central

    Pakula, Andrea; Jones, Amber; Syed, Javed; Skinner, Ruby

    2015-01-01

    Introduction Traumatic diaphragmatic hernia is a rare and often under recognized complication of penetrating and blunt trauma. These injuries are often missed or there is a delay in diagnosis which can lead to enlargement of the defect and the development of abdominal or respiratory symptoms. Presentation of case We report a case of an otherwise healthy 37 year old male who was involved in a motor vehicle accident at age twelve. He presented 25 years later with vague lower abdominal symptoms and was found to have a large chronic left sided diaphragmatic hernia involving the majority of his intra-abdominal contents. Repair of the defect with a biologic mesh was undertaken and the patient also required complex abdominal wall reconstruction due to loss of intra-abdominal domain from the chronicity of the hernia. A staged closure of the abdomen was performed first with placement of a Wittmann patch. Medical management of intra-abdominal hypertension was successful and the midline fascia was sequentially approximated at the bedside for three days. The final closure was performed with a component separation and implantation of a fenestrated biologic fetal bovine mesh to reinforce the closure. In addition, a lightweight Ultrapro mesh was placed for additional lateral reinforcement. The patient recovered well and was discharged home. Discussion These injuries are rare and diagnosis is challenging. Mechanism and CT scan characteristics can aid clinicians. Conclusion Blunt diaphragmatic injury is rare and remains a diagnostic challenge. Depending on the chronicity of the injury, repair may require complex surgical decision making. PMID:25623756

  18. Successful MRI-Guided Focused Ultrasound Uterine Fibroid Treatment Despite an Ostomy and Significant Abdominal Wall Scarring.

    PubMed

    Machtinger, Ronit; Tempany, Clare M C; Kanan Roddy, Angela; Fennessy, Fiona M

    2011-01-01

    We present a case of successful magnetic resonance imaging-guided focused ultrasound surgery (MRgFUS) of a uterine fibroid in a patient with extensive anterior abdominal wall surgical scars from two longitudinal laparotomies, a total colectomy and ileostomy. This case demonstrates that MRgFUS can be safely used in patients with an ostomy and significant abdominal wall scarring, but careful pretreatment planning and positioning during treatment is needed. PMID:21647219

  19. Local influence of calcifications on the wall mechanics of abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    de Putter, Sander; van de Vosse, Frans N.; Breeuwer, Marcel; Gerritsen, Frans A.

    2006-03-01

    Finite element wall stress simulations on patient-specific models of abdominal aortic aneurysm (AAA) may provide a better rupture risk predictor than the currently used maximum transverse diameter. Calcifications in the wall of AAA lead to a higher maximum wall stress and thus may lead to an elevated rupture risk. The reported material properties for calcifications and the material properties actually used for simulations show great variation. Previous studies have focused on simplified modelling of the calcification shapes within a realistic aneurysm shape. In this study we use an accurate representation of the calcification geometry and a simplified model for the AAA. The objective of this approach is to investigate the influence of the calcification geometry, the material properties and the modelling approach for the computed peak wall stress. For four realistic calcification shapes from standard clinical CT images of AAA, we performed simulations with three distinct modelling approaches, at five distinct elasticity settings. The results show how peak wall stress is sensitive to the material properties of the calcifications. For relatively elastic calcifications, the results from the different modelling approaches agree. Also, for relatively elastic calcifications the computed wall stress in the tissue surrounding the calcifications shows to be insensitive to the exact calcification geometry. For stiffer calcifications the different modelling approaches and the different geometries lead to significantly different results. We conclude that an important challenge for future research is accurately estimating the material properties and the rupture potential of the AAA wall including calcifications.

  20. [Combined reconstructive hernioplasty for small and middle-size hernia of the abdominal wall].

    PubMed

    Veligotskiĭ, N N; Komarchuk, E V; Veligotskiĭ, A N; Mekhtikhanov, Z S; Gorbulich, A V; Komarchuk, V V

    2013-05-01

    The results of prosthetic hernioplasty, performed in 61 patients for a small- and middle-size abdominal wall hernia (AWH) were analyzed. In a control group in 18 (29.5%) patients the IPOM-procedure was applied and in the main group in 43 (70.5%)--the combined plasty. Complications, which have had occurred in 2 (11.1%) patients of a control group and in 4 (9.3%)--of the main, were cured using conservative methods. While five-year followup the AWH recurrence was not noted. The introduction of the elaborated tactic of treatment, named the combined reconstructive hernioplasty, have permitted to improve the late functional and cosmetic results due to restoration of abdominal linea alba integrity. PMID:23888804

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  3. Repair of Full-Thickness Defects in Alimentary Tract Wall With Patches of Expanded Polytetrafluoroethylene

    PubMed Central

    Oh, Daniel S.; Manning, Melanie M.; Emmanuel, Janson; Broyles, Stuart E.; Stone, H. Harlan

    2002-01-01

    Objectives To test the efficacy of patches of expanded polytetrafluoroethylene (ePTFE) for the repair of full-thickness defects in alimentary tract wall. Summary Background Data A recent report of successful replacement of duodenal wall with patches of ePTFE was met with skepticism and clearly warranted confirmation as well as evaluation in repair of other segments of the abdominal intestinal tract. Methods Defects of 4 cm2 were created in various segments of canine abdominal alimentary tract (stomach, duodenum, small bowel, and colon) as well as in bladder dome. For the duodenum in 13 dogs, three different ePTFE fabrications were used: CVX (cardiovascular), PDX (preclude dura membrane), and DLM (dual mesh plus). In repair of the other areas in six dogs, the PDX patch was used. When the animals were killed, both gross inspection of the parietes and tissue for histologic study became the basis for evaluation. Peritoneal and intraluminal cultures of the specific study viscera were also taken. Results There were no patch failures. Only six significant adhesions were noted in 3 of the 19 dogs. Serosal surface healing was complete without exception by 1 week in all animals. Patches of CVX and PDX had heaping mucosa at the margin of well-sealed patch edges in the study involving duodenum. However, the DLM patch had an undergrowth of mucosa with partial patch separation by 1 week, beginning patch extrusion into gut lumen at 3 weeks, and total separation of patch with complete mucosal repair at 6 weeks. The fate of the PDX patches at 6 weeks in stomach, small bowel, colon, and bladder was identical to what had been observed for the PDX patch in the duodenum. All peritoneal and bladder cultures had no growth, whereas the contents of the alimentary tract grew expected flora. Conclusions These observations suggest that ePTFE may well be an acceptable membrane for at least temporary replacement of full-thickness hollow viscus defects, even in the face of heavy bacterial contamination, and that certain structural configurations of ePTFE may provide a base for increasing absorptive mucosal surface area. PMID:11981217

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

    SciTech Connect

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

    2007-01-01

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

  5. PET/CT demonstration and monitoring of thoracic and abdominal wall mesothelioma.

    PubMed

    Nguyen, Ba D

    2014-01-01

    Mesothelioma is a malignancy arising from the embryonic coelomic mesodermal lining forming the pleura, peritoneum, pericardium, and tunica vaginalis. It is mostly induced by exposure to asbestos. The author presents a 77-year-old woman with an atypical manifestation of epithelioid mesothelioma, which does not follow the expected clinical characteristics of this disease mentioned above. In this case, PET/CT provides useful information concerning the extension of the lesions to thoracic and abdominal walls not fully evaluated by the initial conventional cross-sectional imaging. PET/CT also allows an accurate therapeutic monitoring of the disease. PMID:23510890

  6. Synovial sarcoma of the abdominal wall: Imaging findings and review of the literature.

    PubMed

    de Haas, Robbert J; Bonenkamp, Johannes J; Flucke, Uta E; de Rooy, Jacky W J

    2015-02-01

    Synovial sarcoma is the fourth most common type of soft-tissue sarcoma (following undifferentiated pleomorphic sarcoma, liposarcoma, and rhabdomyosarcoma), and should be considered a high-grade neoplasm with a high number of local recurrences and late metastases. Synovial sarcoma predominantly occurs in adolescents and young adults, and typically arises near the joints of the lower extremity. However, this tumor can also occur at uncommon sites such as the abdominal wall, which is illustrated in this article. Furthermore, we reviewed the available literatures on the clinical, pathological and radiological appearances, as well as the current knowledge concerning treatment options and prognosis. PMID:25926925

  7. Synovial sarcoma of the abdominal wall: Imaging findings and review of the literature

    PubMed Central

    de Haas, Robbert J.; Bonenkamp, Johannes J.; Flucke, Uta E.; de Rooy, Jacky W.J.

    2015-01-01

    Synovial sarcoma is the fourth most common type of soft-tissue sarcoma (following undifferentiated pleomorphic sarcoma, liposarcoma, and rhabdomyosarcoma), and should be considered a high-grade neoplasm with a high number of local recurrences and late metastases. Synovial sarcoma predominantly occurs in adolescents and young adults, and typically arises near the joints of the lower extremity. However, this tumor can also occur at uncommon sites such as the abdominal wall, which is illustrated in this article. Furthermore, we reviewed the available literatures on the clinical, pathological and radiological appearances, as well as the current knowledge concerning treatment options and prognosis. PMID:25926925

  8. A pilot study on bladder wall thickness at different filling stages

    NASA Astrophysics Data System (ADS)

    Zhang, Xi; Liu, Yang; Li, Baojuan; Zhang, Guopeng; Liang, Zhengrong; Lu, Hongbing

    2015-03-01

    The ever-growing death rate and the high recurrence of bladder cancer make the early detection and appropriate followup procedure of bladder cancer attract more attention. Compare to optical cystoscopy, image-based studies have revealed its potentials in non-invasive observations of the abnormities of bladder recently, in which MR imaging turns out to be a better choice for bladder evaluation due to its non-ionizing and high contrast between urine and wall tissue. Recent studies indicate that bladder wall thickness tends to be a good indicator for detecting bladder wall abnormalities. However, it is difficult to quantitatively compare wall thickness of the same subject at different filling stages or among different subjects. In order to explore thickness variations at different bladder filling stages, in this study, we preliminarily investigate the relationship between bladder wall thickness and bladder volume based on a MRI database composed of 40 datasets acquired from 10 subjects at different filling stages, using a pipeline for thickness measurement and analysis proposed in our previous work. The Student's t-test indicated that there was no significant different on wall thickness between the male group and the female group. The Pearson correlation analysis result indicated that negative correlation with a correlation coefficient of -0.8517 existed between the wall thickness and bladder volume, and the correlation was significant(p <0.01). The corresponding linear regression equation was then estimated by the unary linear regression. Compared to the absolute value of wall thickness, the z-score of wall thickness would be more appropriate to reflect the thickness variations. For possible abnormality detection of a bladder based on wall thickness, the intra-subject and inter-subject thickness variation should be considered.

  9. MMP-9, Homocysteine and CRP Circulating Levels Are Associated with Intraluminal Thrombus Thickness of Abdominal Aortic Aneurysms–New Implication of the Old Biomarkers

    PubMed Central

    Wiernicki, Ireneusz; Millo, Barbara; Safranow, Krzysztof; Gorecka-Szyld, Barbara; Gutowski, Piotr

    2011-01-01

    Background: Abdominal aortic aneurysms (AAAs) are characterized by presence of high proteolytic activity, atherosclerotic lesions, extensive transmural inflammation and the presence of variably sized and shaped intraluminal thrombus (ILT). Therefore, we evaluated a possible association between plasma matrix metalloproteinase-9 (MMP-9), homocysteine (Hcy), high-sensitivity C-reactive protein (hsCRP) levels and ILT thickness in patients with AAA. Methods: Plasma concentrations of MMP-9, Hcy and hsCRP were determined and ILT thickness was measured in 71 patients with AAA. They were divided into 2 groups according to ILT thickness: 34 patients with ILT mean thickness ≥ 9 mm and 37 patients with ILT < 9 mm. Results: Plasma MMP-9 and CRP concentrations in patients with thin ILT were significantly higher than in group with thick ILT (medians 610 vs. 485 ng/mL, p = 0.00003, and 7.7 vs. 3.3 mg/L, p < 0.00001, respectively) In contrast, plasma Hcy concentrations in patients with thin ILT were significantly lower than in the group with thick ILT (medians 14.3 vs. 19.2 μmol/L, p < 0.00001). Multiple regression models adjusted for age and AAA diameter showed that thin ILT is an independent predictor of high MMP-9 and CRP concentrations, while thick ILT predicts high Hcy concentrations. Conclusions: Association of higher plasma levels of MMP-9 and CRP with thin ILT may be related to two phenomena: thin thrombi convey more elastolysis-stimulating factors from blood to the AAA wall and thin thrombi convey more factors involved in proteolysis and inflammation from AAA wall to blood. The association of thin ILT with lower plasma Hcy concentrations may be related to the role of Hcy as a prothrombotic marker and needs further research. PMID:21897000

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

    PubMed

    Vural, Birol; Vural, Fisun; Müezzinoglu, Bahar

    2015-09-01

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

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

    PubMed Central

    Vural, Fisun; Müezzinoglu, Bahar

    2015-01-01

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

  12. A simple and inexpensive technique of upper abdominal wall retraction in pediatric liver surgery and transplantation.

    PubMed

    Wang, Shih-Ho; Concejero, Allan M; Chen, Chao-Long; Wang, Chih-Chi; Lin, Chih-Che; Liu, Yeuh-Wei; Yang, Chin-Hsiang; Yong, Chee-Chien

    2008-03-01

    In majority of centers, pediatric liver surgery and transplantation involves a team of four at any given time: the surgeon, the first and second assistants, and the instrument nurse. This creates considerable crowding around both operative field and operating table. Mechanical devices have been occasionally employed to solve this problem, but most table-mounted devices are designed for adult patients. Based on our experience with pediatric living donor liver transplantation, we developed a simple, safe, and inexpensive method of upper abdominal wall retraction to facilitate surgical exposure and avoid over-crowding in the sterile field. The key points of this technique are the use of the Mercedes incision for liver transplantation or right subcostal incision with upper abdominal midline extension for hepatic resection and an adult-designed Kent retractor. A pediatric-designed Kent retractor is expensive, unnecessary, and may even cause complications as rib fractures and nerve paralysis. We used this technique in 142 consecutive pediatric living donor liver transplants and 16 major hepatectomies in children without any complication resulting from the exposure. The presented technique is simple, safe, reliable, and inexpensive. It can be used in pediatric liver surgery, as well as general pediatric upper abdominal operations. PMID:18307663

  13. Nanotube wall thickness dependent magnetization reversal properties of NiFe nanotubes

    NASA Astrophysics Data System (ADS)

    Sharif, R.; Shamaila, S.; Shaheen, F.; Naseem, S.; Chen, J. Y.; Khaleeq-ur-Rahman, M.; Hussain, K.; Han, X. F.

    2013-01-01

    Nanotube wall thickness dependent magnetization properties of NiFe nanotube arrays electrodeposited in polycarbonate membranes are investigated. A systematic variation of nanotube wall thickness (tw) has been investigated. The magnetization reversal properties are strongly influenced by the variation of tw keeping length and external radius constant.

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

    PubMed Central

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

    2013-01-01

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

  15. Symptomatic schwannoma of the abdominal wall: A case report and review of the literature

    PubMed Central

    BALZAROTTI, RUBEN; RONDELLI, FABIO; BARIZZI, JESSICA; CARTOLARI, ROBERTO

    2015-01-01

    Schwannoma is a rare, benign tumor that arises from the nerve sheath. This tumor usually involves the extremities, but can also be found in the head and neck, trunk, pelvis, retroperitoneum, mediastinum and gastrointestinal tract. In numerous cases, the tumors are asymptomatic and are identified incidentally on physical examination or imaging. Occasionally, schwannoma is symptomatic due to compression of surrounding large nerves. In the present study, a 57-year-old female presented to the surgical outpatient’s department due to a well-localized parietal pain in the left lower quadrant. The onset of the pain occurred three years prior to presentation, without apparent cause and in the absence of other symptoms. Ultrasound and a computed tomography scan revealed a small solid tumor in the anterior abdominal wall, which was dimensionally stable over time, but was not noted in a preliminary analysis by a radiologist. The lesion was surgically removed using an anterior surgical approach. Histopathology revealed the tumor to be benign schwannoma. The painful symptoms completely disappeared. To the best of our knowledge, this is the third case of an abdominal wall benign schwannoma in the medical literature, and the first symptomatic case. PMID:25663862

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

    PubMed

    Fechner, R; Schwarz-Wings, D

    2013-06-01

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

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

    PubMed Central

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

    2016-01-01

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

  18. Effects of Antimony and Wall Thickness on Graphite Morphology in Ductile Iron Castings

    NASA Astrophysics Data System (ADS)

    Glavas, Zoran; Strkalj, Anita; Maldini, Kresimir

    2016-05-01

    Effects of Sb additions on the graphite morphology of ductile iron castings in different wall thicknesses (3, 12, 25, 38, 50, 75, and 100 mm) were analyzed in this paper. In the wall thicknesses of 3, 12, and 25 mm, low contents of rare earth (RE) elements showed a beneficial effect on nodule count and nodularity. Nodularity >80 pct and a high nodule count were achieved without the addition of Sb. In the wall thicknesses of 38, 50, 75, and 100 mm, nodularity >80 pct was not achieved without the use of the chill or proper content of Sb. Excess of RE elements was neutralized with the addition of proper amount of Sb to the wall thickness. Addition of 0.01 wt pct Sb (ratio of RE/Sb = 0.34, ratio of RE/SE = 0.105) was sufficient to achieve nodularity >80 pct in the wall thicknesses of 38, 50, 75, and 100 mm.

  19. A Digital Stereomicroscopic Study of the Radicular Wall Thickness of Two-Canal Mandibular Incisors

    PubMed Central

    Khedmat, Sedigheh; Mohamadian, Sohayla; Kharrazifard, Mohamad Javad

    2015-01-01

    Objectives: This study aimed to assess the radicular wall thickness in mandibular incisors with two canals and find the maximum and minimum thickness to prevent root canal treatment (RCT) procedural errors. Materials and Methods: A total of 160 extracted mandibular incisors were selected and radiographed; out of which, 55 had two canals. Three parallel transverse sections were made in each tooth at 1mm below the cementoenamel junction (CEJ), mid-root and 1 millimeter to the apex. Specimens were evaluated under a stereomicroscope and the thickness of radicular walls in each section was determined for the buccal, lingual and proximal surfaces. Data were statistically analyzed using Pearson’s correlation coefficient test. Results: The thickness of radicular wall decreased from the cervical towards the apex. In all three sections (cervical, mid-root and apical), the thickness of lingual wall was significantly greater than the buccal wall. Also, the thickness of buccal and lingual walls was significantly higher than that of the proximal walls. Conclusion: The lingual radicular wall had the highest thickness in two-canal mandibular incisors. Therefore, in these teeth, the lingual canal is a better choice for post placement. PMID:26877738

  20. Method of manufacturing hollow members having uniform wall thickness through use of ablation

    DOEpatents

    Anderson, Paul R.; Downs, Raymond L.; Henderson, Timothy M.

    1982-01-01

    A method of manufacturing a hollow structure of uniform wall thickness comprising the steps of selecting or forming a precursor having one wall surface of desired geometry, treating a portion of the precursor consisting of the one wall surface and a uniform depth of material beneath the wall surface to increase resistance to ablation, and then removing by ablation and discarding the remaining or untreated portion of the precursor.

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

    PubMed

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

    2012-10-01

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

  2. The Effects of Horse Riding Simulation Training on Stroke Patients’ Balance Ability and Abdominal Muscle Thickness Changes

    PubMed Central

    Baek, Il-Hun; Kim, Byeong Jo

    2014-01-01

    [Purpose] The purpose of this study was to assess the effects of horse riding simulation training on changes in balance ability and abdominal muscle thicknesses of stroke patients. [Subjects] Thirty stroke patients with hemiplegia were recruited, and they were randomly assigned to a control or experimental group. [Methods] The experimental group performed horse riding simulation training, whereas the control group performed trunk exercises for 8 weeks. Balance ability was measured using a BioRescue system. The thicknesses of subjects’ external oblique, internal oblique, and transversus abdominis muscles were measured by ultrasonic imaging. [Results] In the experimental group, balance ability was significantly improved after training. Similarly, the thickness of the abdominal muscles on the affected side changed after training in the experimental group, whereas the control group showed no statistically significant changes. [Conclusion] We suggest that horse riding simulation training is more effective than trunk exercises at reducing the center of pressure path length and travel speed and improving the asymmetry of the abdominal muscles of stroke patients. PMID:25202200

  3. The effects of horse riding simulation training on stroke patients' balance ability and abdominal muscle thickness changes.

    PubMed

    Baek, Il-Hun; Kim, Byeong Jo

    2014-08-01

    [Purpose] The purpose of this study was to assess the effects of horse riding simulation training on changes in balance ability and abdominal muscle thicknesses of stroke patients. [Subjects] Thirty stroke patients with hemiplegia were recruited, and they were randomly assigned to a control or experimental group. [Methods] The experimental group performed horse riding simulation training, whereas the control group performed trunk exercises for 8 weeks. Balance ability was measured using a BioRescue system. The thicknesses of subjects' external oblique, internal oblique, and transversus abdominis muscles were measured by ultrasonic imaging. [Results] In the experimental group, balance ability was significantly improved after training. Similarly, the thickness of the abdominal muscles on the affected side changed after training in the experimental group, whereas the control group showed no statistically significant changes. [Conclusion] We suggest that horse riding simulation training is more effective than trunk exercises at reducing the center of pressure path length and travel speed and improving the asymmetry of the abdominal muscles of stroke patients. PMID:25202200

  4. Abdominal wall metastasis following open nephroureterectomy for upper tract urothelial carcinoma in a patient with Lynch syndrome.

    PubMed

    Stewart, Michael John; Guerra, Glen R; Sutherland, Tom R; Elmer, Sandra L

    2016-01-01

    A 74-year-old man developed the rare complication of an abdominal wall metastasis following open nephroureterectomy for upper tract urothelial carcinoma (UTUC). This occurred in the setting of synchronous contralateral ureteric and metachronous colorectal carcinomas. Immunohistochemistry demonstrated loss of the mutS homolog 6 (MSH6) mismatch repair (MMR) protein in the metastatic abdominal wall and colonic lesions, which in conjunction with meeting the Amsterdam II criteria, is strongly suggestive of Lynch syndrome (LS). Surgical resection of the recurrence was performed with clear margins and neither recurrence nor spread during short-term follow-up. PMID:27033297

  5. The Bulging Behavior of Thick-Walled 6063 Aluminum Alloy Tubes Under Double-Sided Pressures

    NASA Astrophysics Data System (ADS)

    Cui, Xiao-Lei; Wang, Xiao-Song; Yuan, Shi-Jian

    2015-05-01

    To make further exploration on the deformation behavior of tube under double-sided pressures, the thick-walled 6063 aluminum alloy tubes with an outer diameter of 65 mm and an average thickness of 7.86 mm have been used to be bulged under the combined action of internal and external pressures. In the experiment, two ends of the thick-walled tubes were fixed using the tooth and groove match. Three levels of external pressure (0 MPa, 40 MPa, and 80 MPa), in conjunction with the internal pressure, were applied on the tube outside and inside simultaneously. The effect of external pressure on the bulging behavior of the thick-walled tubes, such as the limiting expansion ratio, the bulging zone profile, and the thickness distribution, has been investigated. It is shown that the limiting expansion ratio, the bulging zone profile, and the thickness distribution in the homogeneous bulging area are all insensitive to the external pressure. However, the external pressure can make the thick-walled tube achieve a thinner wall at the fracture area. It reveals that the external pressure can only improve the fracture limit of the thick-walled 6063 tubes, but it has very little effect on their homogeneous bulging behavior. It might be because the external pressure can only increase the magnitude of the hydrostatic pressure for the tube but has no effect on the Lode parameter.

  6. Patient-specific left atrial wall-thickness measurement and visualization for radiofrequency ablation

    NASA Astrophysics Data System (ADS)

    Inoue, Jiro; Skanes, Allan C.; White, James A.; Rajchl, Martin; Drangova, Maria

    2014-03-01

    INTRODUCTION: For radiofrequency (RF) catheter ablation of the left atrium, safe and effective dosing of RF energy requires transmural left atrium ablation without injury to extra-cardiac structures. The thickness of the left atrial wall may be a key parameter in determining the appropriate amount of energy to deliver. While left atrial wall-thickness is known to exhibit inter- and intra-patient variation, this is not taken into account in the current clinical workflow. Our goal is to develop a tool for presenting patient-specific left atrial thickness information to the clinician in order to assist in the determination of the proper RF energy dose. METHODS: We use an interactive segmentation method with manual correction to segment the left atrial blood pool and heart wall from contrast-enhanced cardiac CT images. We then create a mesh from the segmented blood pool and determine the wall thickness, on a per-vertex basis, orthogonal to the mesh surface. The thickness measurement is visualized by assigning colors to the vertices of the blood pool mesh. We applied our method to 5 contrast-enhanced cardiac CT images. RESULTS: Left atrial wall-thickness measurements were generally consistent with published thickness ranges. Variations were found to exist between patients, and between regions within each patient. CONCLUSION: It is possible to visually determine areas of thick vs. thin heart wall with high resolution in a patient-specific manner.

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

    PubMed Central

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

    1995-01-01

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

  8. Method and apparatus for determining diameter and wall thickness of minute hollow spherical shells

    DOEpatents

    Steinman, D.A.

    1980-05-30

    Method and apparatus for determining diameter and wall thickness of hollow microspheres or shells wherein terminal velocities of shells traveling in fluid-filled conduits of differing diameters are measured. A wall-effect factor is determined as a ratio of the terminal velocities, and shell outside diameter may then be ascertained as a predetermined empirical function of wall-effect factor. For shells of known outside diameter, wall thickness may then be ascertained as a predetermined empirical function of terminal velocity in either conduit.

  9. Method and apparatus for determining diameter and wall thickness of minute hollow spherical shells

    DOEpatents

    Steinman, David A.

    1982-01-01

    Method and apparatus for determining diameter and wall thickness of hollow microspheres or shells wherein terminal velocities of shells traveling in fluid-filled conduits of differing diameters are measured. A wall-effect factor is determined as a ratio of the terminal velocities, and shell outside diameter may then be ascertained as a predetermined empirical function of wall-effect factor. For shells of known outside diameter, wall thickness may then be ascertained as a predetermined empirical function of terminal velocity in either conduit.

  10. Laparoscopic transabdominal preperitoneal herniorrhaphy using abdominal wall-lifting method under regional anesthesia: a preliminary report.

    PubMed

    Tagaya, N; Kita, J; Kogure, H

    1995-08-01

    This report describes a laparoscopic transabdominal preperitoneal herniorrhaphy of groin hernias using an abdominal wall-lifting method under regional anesthesia as compared with pneumoperitoneum under general anesthesia. The series of studies involved the repair of 20 groin hernias; 7 hernias were direct, 11 were indirect, and 2 were femoral. These included 7 recurrent, 1 incarcerated, and 4 bilateral hernias. There were no intraoperative complications, and both procedures required no conversion to open surgery. There are no significant differences between the two groups in operative time and postoperative hospital stay. The only postoperative complication of our procedure was temporary inguinal pain in 2 cases. The follow-up period ranged from 8 to 17 months. To date, no recurrence has developed. We conclude that our procedure is a safe, technically feasible, and useful method to perform laparoscopic herniorrhaphy for groin hernias. PMID:7579672

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

    PubMed Central

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

    2015-01-01

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

  12. 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

  13. Echinococcus multilocularis infection of the liver presenting as abdominal wall fistula

    PubMed Central

    Juodeikis, Zygimantas; Poskus, Tomas; Seinin, Dmitrij; Strupas, Kestutis

    2014-01-01

    Echinococcus multilocularis causes infection where the most commonly affected organ is the liver, followed by the lung, kidney, bone and the brain. Other sites such as the heart, spleen, pancreas and soft tissues are very rarely affected. Surgical treatment combined with chemotherapy using various technical approaches remains the main therapeutic modality for echinococcal liver disease. To the best of our knowledge there are less than five clinical cases of cutaneous presentation of liver alveolar echinococcosis described. We present a unique case of liver echinococcosis presenting as recurrent abdominal wall fistula and abscess in a 29-year-old man. Diagnosis was based on CT imaging, serological analysis and histological findings from the fistula. Medical treatment with albendazole was initiated and liver resection was performed. The patient has no symptoms and signs of recurrence 1 year after operation, while still on albendazole therapy. This case description highlights the importance of early suspicion and treatment of unusual echinococcosis clinical presentations. PMID:24810453

  14. 49 CFR 179.500-4 - Thickness of wall.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the marked test pressure of the tank, the calculated fiber stress in psi at inner wall of tank multiplied by 3.0 will not exceed the tensile strength of any specimen taken from the tank and tested as... maximum marked test pressure permitted to be marked on the tank shall be made by the formula: P = [10S(D...

  15. 49 CFR 179.500-4 - Thickness of wall.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... pressure equal to 7/10 of the marked test pressure of the tank, the calculated fiber stress in psi at inner wall of tank multiplied by 3.0 will not exceed the tensile strength of any specimen taken from the tank... to determine the maximum marked test pressure permitted to be marked on the tank shall be made by...

  16. 49 CFR 179.500-4 - Thickness of wall.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the marked test pressure of the tank, the calculated fiber stress in psi at inner wall of tank multiplied by 3.0 will not exceed the tensile strength of any specimen taken from the tank and tested as... maximum marked test pressure permitted to be marked on the tank shall be made by the formula: P = [10S(D...

  17. 49 CFR 179.500-4 - Thickness of wall.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the marked test pressure of the tank, the calculated fiber stress in psi at inner wall of tank multiplied by 3.0 will not exceed the tensile strength of any specimen taken from the tank and tested as... maximum marked test pressure permitted to be marked on the tank shall be made by the formula: P = [10S(D...

  18. 49 CFR 179.500-4 - Thickness of wall.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the marked test pressure of the tank, the calculated fiber stress in psi at inner wall of tank multiplied by 3.0 will not exceed the tensile strength of any specimen taken from the tank and tested as... maximum marked test pressure permitted to be marked on the tank shall be made by the formula: P = [10S(D...

  19. Method of controlling the side wall thickness of a turbine nozzle segment for improved cooling

    DOEpatents

    Burdgick, Steven Sebastian (Schenectady, NY)

    2002-01-01

    A gas turbine nozzle segment has outer and inner bands and a vane extending therebetween. Each band has a side wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band has an inturned flange defining with the nozzle wall an undercut region. The outer surface of the side wall is provided with a step prior to welding the cover to the side wall. A thermal barrier coating is applied in the step and, after the cover is welded to the side wall, the side wall is finally machined to a controlled thickness removing all, some or none of the coating.

  20. Deletion of Mesenchymal Glucocorticoid Receptor Attenuates Embryonic Lung Development and Abdominal Wall Closure

    PubMed Central

    Stoner, Shihani; Tuckermann, Jan; Seibel, Markus; Zhou, Hong

    2013-01-01

    As a member of the nuclear hormone receptor superfamily of ligand-activated transcription factors, the glucocorticoid receptor (GR) is essential for normal embryonic development. To date, the role of mesenchymal glucocorticoid signaling during development has not been fully elucidated. In the present study, we investigated the role of the GR during embryogenesis specifically in mesenchymal tissues. To this aim, we crossed GRflox mice with Dermo1-Cre mice to generate GRDermo1 mice, where the GR gene was deleted within mesenchymal cells. Compared to their wild type littermates, GRDermo1 mice displayed severe pulmonary atelectasis, defects in abdominal wall formation resulting in intestinal herniation, abnormal extracellular matrix synthesis in connective tissues and high postnatal lethality. Lungs of GRDermo1 mice failed to progress from the canalicular to saccular stage, as evidenced by the presence of immature air sacs, thickened interstitial mesenchyme and an underdeveloped vascular network between E17.5 and E18.5. Furthermore, myofibroblasts and vascular smooth muscle cells, although present in normal numbers in GRDermo1 animals, were characterized by significantly reduced elastin synthesis, whilst epithelial lining cells of the immature saccules were poorly differentiated. A marked reduction in normal elastin and collagen deposits were also observed in connective tissues adjacent to the umbilical hernia. This study demonstrates that eliminating the GR in cells of the mesenchymal lineage results in marked effects on interstitial fibroblast function, including a significant decrease in elastin synthesis. This results in lung atelectasis and postnatal lethality, as well as additional and hitherto unrecognized developmental defects in abdominal wall formation. In addition, altered glucocorticoid signaling in the mesenchyme attenuates normal lung epithelial differentiation. PMID:23696835

  1. Repair of Abdominal Wall Defects with Biodegradable Laminar Prostheses: Polymeric or Biological?

    PubMed Central

    Pascual, Gemma; Sotomayor, Sandra; Rodríguez, Marta; Pérez-Köhler, Bárbara; Bellón, Juan M.

    2012-01-01

    Introduction Biological and synthetic laminar absorbable prostheses are available for the repair of hernia defects in the abdominal wall. They share the important feature of being gradually degraded in the host, resulting in place the formation of a neotissue. This study was designed to assess the host tissue’s incorporation of collagen bioprostheses and a synthetic absorbable prosthesis. Methods Partial defects were created in the abdominal walls of 72 New Zealand rabbits and repaired using collagen bioprostheses Tutomesh® and Strattice® or a synthetic prosthesis Bio-A®. Specimens were collected for light microscopy, collagens gene and protein expression, macrophage response and biomechanical resistance at 14, 30, 90 and 180 days post-implantation. Results Tutomesh® and Bio-A® were gradually infiltrated by the host tissue and almost completely degraded by 180 days post-implantation. In contrast, Strattice® exhibited material encapsulation, no prosthetic degradation and low cell infiltration at earlier timepoints, whereas at later study time, collagen deposition could be observed within the mesh. In the short term, Bio-A® exhibited higher level of collagen 1 and 3 mRNA expression compared with the two other biological prostheses, which exhibited two peaks of higher expression at 14 and 90 days. The expression of collagen III was homogeneous throughout the study and collagen I deposition was more evident in Strattice®. Macrophage response decreased over time in biomeshes. However, in the synthetic mesh remained high and homogeneous until 90 days. The biomechanical analysis demonstrated the progressively increasing tensile strength of all biomaterials. Conclusions The tissue infiltration of laminar absorbable prostheses is affected by the structure and composition of the mesh. The synthetic prosthesis exhibited a distinct pattern of tissue incorporation and a greater macrophage response than did the biological prostheses. Of all of the laminar, absorbable biomaterials that were tested in this study, Strattice® demonstrated the optimal levels of integration and degradation. PMID:23285119

  2. Forces and deformations of the abdominal wall--a mechanical and geometrical approach to the linea alba.

    PubMed

    Förstemann, T; Trzewik, J; Holste, J; Batke, B; Konerding, M A; Wolloscheck, T; Hartung, C

    2011-02-24

    Force-elongation responses of the human abdominal wall in the linea alba region were determined by tensile tests in which the linea alba was seen to exhibit a nonlinear elastic, anisotropic behavior as is frequently observed in soft biological tissues. In addition, the geometry of the abdominal wall was determined, based on MRI data. The geometry can be specified by principal radii of curvature in longitudinal of approximately 470 mm and in the transverse direction of about 200 mm. The determined radii agree with values found in other studies. Mechanical stresses, deformations and abdominal pressures for load cases above 6% elongation can be related using Laplace's formula and our constitutive and geometrical findings. Results from uni- and biaxial tensile tests can thus be compared using this model. Calculations confirm that abdominal pressures of approximately 20 kPa correspond to related biaxial forces of about 3.4N/mm in the transverse and 1.5 N/mm in the longitudinal direction. Young's moduli can be calculated with respect to the uniaxial as well as the biaxial loading. At these physiological loadings, a compliance ratio of about 2:1 between the longitudinal and transversal directions is found. Young's moduli of about 50 kPa occur in transversal direction and of about 20 kPa in longitudinal direction at transverse and longitudinal strains both in the order of 6%. These findings coincide with results from other investigations in which the properties of the abdominal wall have been examined. PMID:21130459

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

    PubMed Central

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

    2010-01-01

    Study Design Cadaveric analysis of human abdominal muscle architecture. Objective To quantify the architectural properties of rectus abdominis (RA), external oblique (EO), internal oblique (IO) and transverse abdominis (TrA), and model mechanical function in light of these new data. Summary of Background Data Knowledge of muscle architecture provides the structural basis for predicting muscle function. Abdominal muscles greatly affect spine loading, stability, injury prevention and rehabilitation; however, their architectural properties are unknown. Methods Abdominal muscles from eleven elderly human cadavers were removed intact, separated into regions and micro-dissected for quantification of physiological cross-sectional area (PCSA), fascicle length and sarcomere length. From these data, sarcomere operating length ranges were calculated. Results IO had the largest PCSA and RA the smallest, and would thus generate the largest and smallest isometric forces, respectively. RA had the longest fascicle length, followed by EO, and would thus be capable of generating force over the widest range of lengths. Measured sarcomere lengths, in the post-mortem neutral spine posture, were significantly longer in RA and EO (3.29±0.07 and 3.18±0.11 μm) compared to IO and TrA (2.61±0.06 and 2.58±0.05 μm) (p < 0.0001). Biomechanical modeling predicted that RA, EO and TrA act at optimal force-generating length in the mid-range of lumbar spine flexion, where IO can generate approximately 90% of its maximum force. Conclusions These data provide clinically relevant insights into the ability of the abdominal wall muscles to generate force and change length throughout the lumbar spine range of motion. This will impact the understanding of potential postures in which the force-generating and spine stabilizing ability of these muscles become compromised, which can guide exercise/rehabilitation development and prescription. Future work should explore the mechanical interactions among these muscles and their relationship to spine health and function. PMID:21325932

  4. Real-time velocimetry for evaluation of change in thickness of arterial wall.

    PubMed

    Kanai, H; Koiwa, Y

    2000-03-01

    We previously developed a new method, namely, the phased tracking method, for accurately tracking the movement of the heart wall and arterial wall based on both the phase and magnitude of the demodulated signals to determine the instantaneous position of an object. By this method, the local change in wall thickness during one heartbeat can be determined. We have now developed a real-time system for measuring change in thickness of the myocardium and arterial wall. In this system, four high-speed digital signal processing (DSP) chips are employed for obtaining the initially developed method in real time. The tracking results for both sides of the wall are superimposed on the M (motion)-mode image in the workstation, and the thickness changes of the arterial wall are displayed in real time. Using this system, reported herein, velocity signals of the arterial wall with amplitudes less than several micrometers can be successfully detected in real time with sufficient reproducibility. The elasticity of the arterial wall is evaluated by referring to the blood pressure. In in vivo experiments, the rapid response of the change in wall thickness of the carotid artery to the dose of nitroglycerine (NTG) is evaluated for a young healthy subject and a young smoker. This new real-time system offers potential for quantitative diagnosis of early-stage atherosclerosis by the transient evaluation of the rapid response of the cardiovascular system to physiological stress. PMID:10829692

  5. Mitigating the effects of surface morphology changes during ultrasonic wall thickness monitoring

    NASA Astrophysics Data System (ADS)

    Cegla, Frederic; Gajdacsi, Attila

    2016-02-01

    Ultrasonic wall thickness monitoring using permanently installed sensors has become a tool to monitor pipe wall thicknesses online and during plant operation. The repeatability of measurements with permanently installed transducers is excellent and can be in the nanometer range. It has, however, also been shown that the measured wall thickness is dependent on surface morphology and that when there are changes in surface morphology the monitored thickness trends can be affected. With an adaptive cross correlation approach, this effect can be successfully muted. However, under some surface morphology change conditions, this can also lead to inaccuracies. Here, an approach to detect when surface morphology changes can influence trend accuracies is presented. This method requires the combination of measurements from several sensors that independently sample an area where the same wall loss mechanism is assumed to occur. Simulation results for the effectiveness of the technique are presented.

  6. A microfluidic device approach to generate hollow alginate microfibers with controlled wall thickness and inner diameter

    NASA Astrophysics Data System (ADS)

    Pham, Uyen H. T.; Hanif, Madiha; Asthana, Amit; Iqbal, Samir M.

    2015-06-01

    Alginate is a natural polymer with inherent biocompatibility. A simple polydimethylsiloxane (PDMS) microfluidic device based self-assembled fabrication of alginate hollow microfibers is presented. The inner diameter as well as wall thickness of the microfibers were controlled effortlessly, by altering core and sheath flow rates in the microfluidic channels. The gelation/cross-linking occured while the solutions were ejected. The microfibers were generated spontaneously, extruding out of the outlet microchannel. It was observed that the outer diameter was independent of the flow rates, while the internal diameter and wall thickness of the hollow fibers were found to be functions of the core and sheath flow rates. At a constant sheath flow, with increasing core flow rates, the internal diameters increased and the wall thicknesses decreased. At a fixed core flow, when sheath flow rate increased, the internal diameters decreased and the wall thickness increased. The immobilization of enzymes in such hollow microfibers can be a potential application as microbioreactors.

  7. What We Know About Management of Traumatic Abdominal Wall Hernia: Review of the Literature and Case Report

    PubMed Central

    Hamidian Jahromi, Alireza; Skweres, Justin; Sangster, Guillermo; Johnson, Lester; Samra, Navdeep

    2015-01-01

    Traumatic abdominal wall hernia (TAWH) is an uncommon form of hernia caused by blunt traumatic disruption of the abdominal wall musculature/fascia and abdominal organ herniation. Diagnosis of TAWH is challenging and requires a high level of suspicion. This form of hernia seems to be underrepresented in the English-language medical literature. There is currently no consensus on the optimal management for TAWH. In this article, we discuss the management of a 36-year-old motorcycle driver who was involved in a road traffic accident. On evaluation at our trauma center, he was found to have TAWH. Diagnostic criteria, imaging modalities and different management options for TAWH will be discussed. PMID:25692423

  8. The study on ``load relief`` mechanism of multiple cracks in thick-wall cylinder

    SciTech Connect

    Zhang, Y.H.; Huang, Z.Z.; Tan, Y.; Chen, L.Y.; Pan, B.Z.

    1995-11-01

    In this paper, the stress field on a given cross section in a thick-wall cylinder with single or multiple cracks is analyzed by means of 3-D photoelastic. Based on the study of the effect of crack on stress field, the concept of ``Additional Bending Moment`` is presented and the expression for non-dimensional ABM, M, is derived. The ``load relief`` mechanism of multiple cracks in a thick-wall cylinder is studied.

  9. Serial Clinical Examinations of 100 Patients Treated for Anterior Abdominal Wall Stab Wounds: A Cross Sectional Study

    PubMed Central

    Herfatkar, Mohammad Rasool; Mobayen, Mohammad Reza; Karimian, Mehdi; Rahmanzade, Fariba; Baghernejad Monavar Gilani, Sadaf; Baghi, Iraj

    2015-01-01

    Background: The current approach in stab wounds of the anterior abdominal wall is still unclear. Objectives: The goal of this study was to evaluate serial clinical examinations of patients with abdominal wall stab wounds referred to Poursina Hospital in Rasht. Patients and Methods: In a cross sectional study, 100 cases with stab wounds to the anterior abdominal wall were examined serially (admission time, 4, 8, 12, and 24 hours) after wound exploration. Serial hemoglobin test was performed every 8 hours. Laparotomy was performed in cases who were not hemodynamically stable or who showed symptoms of peritonitis. The results were analyzed with SPSS software version 21. Results: Ninety-one men (91%) and 9 women (9%) with mean age of 27 10.7 years were included. Coexisting injuries were prevalent in 12 cases. The duration of hospitalization was 1 day in 31%, 2 days in 30%, 3 - 4 days in 32% and more than 5 days in 7%. Late laparotomy was performed 12 hours after admission in 8% of patients due to peritonitis. There was visceral damage in these cases. No mortality occurred. The cost and duration of hospitalization was significantly higher in cases with coexisting injuries and those who underwent laparotomy. Conclusions: It seems serial clinical examinations are safe and decrease the cost and duration of hospitalization in stable patients with anterior abdominal wall stab wounds. PMID:26839861

  10. 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. PMID:26880884

  11. 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

  12. Modified Phased Tracking Method for Measurement of Change in Thickness of Arterial Wall

    NASA Astrophysics Data System (ADS)

    Hasegawa, Hideyuki; Kanai, Hiroshi; Koiwa, Yoshiro

    2002-05-01

    In this study, the change in thickness of the arterial wall caused by the heartbeat was measured by the phased tracking method [IEEE Trans. UFFC. 43 (1996) 791] for noninvasive assessment of the regional elasticity of the arterial wall. In the phased tracking method, the change in thickness of the arterial wall is obtained from the difference between displacements of two points set along an ultrasonic beam. The displacement during the pulse repetition interval is determined by the phase of the complex correlation between the quadrature modulated ultrasonic waves. For suppressing noise components, the complex correlation function is spatially averaged in the region, which corresponds to the ultrasonic wavelength. However, spatial averaging of displacements is not desirable for measurement of the change in thickness, because the change in thickness is caused by the spatial inhomogeneity of displacements. In this paper, the phased tracking method was modified for direct estimation of the change in thickness without spatial averaging of displacements.

  13. Post-cast EDM method for reducing the thickness of a turbine nozzle wall

    DOEpatents

    Jones, Raymond Joseph; Bojappa, Parvangada Ganapathy; Kirkpatrick, Francis Lawrence; Schotsch, Margaret Jones; Rajan, Rajiv; Wei, Bin

    2002-01-01

    A post-cast EDM process is used to remove material from the interior surface of a nozzle vane cavity of a turbine. A thin electrode is passed through the cavity between opposite ends of the nozzle vane and displaced along the interior nozzle wall to remove the material along a predetermined path, thus reducing the thickness of the wall between the cavity and the external surface of the nozzle. In another form, an EDM process employing a profile as an electrode is disposed in the cavity and advanced against the wall to remove material from the wall until the final wall thickness is achieved, with the interior wall surface being complementary to the profile surface.

  14. Prevalence and histopathological finding of thin-walled and thick-walled Sarcocysts in slaughtered cattle of Karaj abattoir, Iran.

    PubMed

    Nourollahi-Fard, Saeid R; Kheirandish, Reza; Sattari, Saeid

    2015-06-01

    Sarcocystosis is a zoonotic disease caused by Sarcocystis spp. with obligatory two host life cycle generally alternating between an herbivorous intermediate host and a carnivorous definitive host. Some species of this coccidian parasite can cause considerable morbidity and mortality in cattle. The present study was set to investigate the prevalence of Sarcocystis spp. and type of cyst wall in slaughtered cattle of Karaj abattoir, Iran. For this purpose 125 cattle (88 males and 37 females) were investigated for the presence of macroscopic and microscopic Sarcocystis cysts in muscular tissues. No macroscopic Sarcocystis cysts were found in any of the samples. In light microscopy, 121 out of 125 cattle (96.8 %) had thin-walled cysts of Sarcocystis cruzi, while 43 out of them (34.4 %) had thick-walled Sarcocystis cyst. In this survey, the most infected tissue was esophagus and heart and the less was diaphragm. Thin-walled cysts (S. cruzi) mostly found in heart and skeletal muscle showed the less. However, thick-walled cyst (S. hominis or S. hirsuta) mostly were detected in diaphragm, heart muscle showed no thick-walled cyst. No significant relation was observed between age and sex and the rate of infection. The results showed that Sarcocystis cyst is prevalent in cattle in the North part of Iran and the evaluation of infection potential can be useful when considering control programs. PMID:26064016

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

    PubMed

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

    2016-06-01

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

  16. 3-D segmentation and quantitative analysis of inner and outer walls of thrombotic abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

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

    2008-03-01

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

  17. Tntraoperative vesical pressure measurements as a guide in the closure of abdominal wall defects.

    PubMed

    Rizzo, A; Davis, P C; Hamm, C R; Powell, R W

    1996-03-01

    Increased intra-abdominal pressure represents a difficult problem when closing abdominal wall defects (AWD) and can cause renal insufficiency and vascular injury to the intestine with the development of necrotizing enterocolitis. Urinary bladder pressure measurements have been shown to accurately reflect intra-abdominal pressure in animal models. This study compares outcomes with and without vesical pressure measurements in AWD. Since its description in 1987, these vesical pressure measurements have guided the closure of AWDs. A pressure of <20 cm H2O allows closure by primary fascial, skin, or staged prosthetic closure. All charts of patients who underwent AWD closure from 1981 to 1993 were reviewed and data collected including type of defect and closure, gestational age, weight, age at operation, fluid requirements and urinary outputs, ventilator requirements, days to first and total feeding, total parenteral nutrition (TPN) days, hospital days, hospital charges, morbidity, and mortality. Results were analyzed by paired or unpaired Student's t test or Fisher's exact test. Twenty-seven infants did not receive vesical pressure measurements, whereas 13 did. No significant differences occurred in the parameters recorded in these two diverse groups. When gastroschisis patients only were compared, a significant decrease in intravenous fluid requirements in the vesical measurement group occurred on postoperative Day 2 (155.3+/- 37.5 versus 109.6 +/- 34.3; P = 0.016), and a significant decrease in urinary output occurred on postoperative Day 3 (4.2 +/- 112 versus 3.1+/- 1.1; P=0.044). Ventilator support, TPN days, and oral feeding data were all lower in the vesical measurement group but did not reach statistical significance. Hospital days and hospital changes showed a trend to lower values in the measured group (P values 0.052 and 0.095, respectively). Intraoperative vesical pressure measurements represent a simple, safe, effective method to guide the closing of AWD and result in less capillary leak and more prompt diuresis, and may result in significantly less morbidity, mortality, and cost. PMID:8607577

  18. Developing a new methodology to characterize in vivo the passive mechanical behavior of abdominal wall on an animal model.

    PubMed

    Simón-Allué, R; Montiel, J M M; Bellón, J M; Calvo, B

    2015-11-01

    The most common surgical repair of abdominal wall hernia goes through implanting a mesh that substitutes the abdominal muscle/fascia while it is healing. To reduce the risk of relapse or possible complications, this mesh needs to mimic the mechanical behavior of the muscle/fascia, which nowadays is not fully determined. The aim of this work is to develop a methodology to characterize in vivo the passive mechanical behavior of the abdominal wall. For that, New Zealand rabbits were subjected to pneumoperitoneum tests, taking the inner pressure from 0 mmHg to 12 mmHg, values similar to those used in human laparoscopies. Animals treated were divided into two groups: healthy and herniated animals with a surgical mesh (polypropylene Surgipro(TM) Covidien) previously implanted. All experiments were recorded by a stereo rig composed of two synchronized cameras. During the postprocessing of the images, several points over the abdominal surface were tracked and their coordinates extracted for different levels of internal pressure. Starting from that, a three dimensional model of the abdominal wall was reconstructed. Pressure-displacement curves, radii of curvature and strain fields were also analysed. During the experiments, animals tissue mostly deformed during the first levels of pressure, showing the noticeable hyperelastic passive behavior of abdominal muscles. Comparison between healthy and herniated specimen displayed a strong stiffening for herniated animals in the zone where the high density mesh was situated. Cameras were able to discern this change, so this method can be used to measure the possible effect of other meshes. PMID:26209832

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  1. Chest wall thickness measurements: The alternative approach extended for {sup 241}Am

    SciTech Connect

    Kramer, G.H.; Burns, L.C.

    1997-02-01

    The Human Monitoring Laboratory has extended the technique of determining the chest wall thickness of an individual using information from the spectrum produced by internally deposited radionuclides. The technique has been investigated both theoretically and practically using germanium detectors and the Lawrence Livermore Torso Phantom. The phantom was used with a lung set containing homogeneously distributed {sup 241}Am. Chest wall thicknesses were varied by using a series of muscle equivalent overlay plates that gave a range of 1.6 cm to 3.9 cm thickness. It was found that a 3-cm chest wall thickness can be estimated to within 18%. Using a spectral addition technique 1 kBq was estimated to be the {open_quotes}practical{close_quotes} lower limit of activity for this method. 7 refs., 2 figs., 3 tabs.

  2. Chest wall thickness measurements of the LLNL and JAERI torso phantoms for germanium detector counting

    SciTech Connect

    Kramer, G.H.; Hauck, B.M.

    1997-11-01

    The Lawrence Livermore National Laboratory and Japanese Atomic Energy Research Institute torso phantoms were developed to calibrate lung counting systems that are used to estimate plutonium and other radionuclides deposited in the lung. Originally, low energy photon counting systems consisted of phoswich detectors. The average chest wall thicknesses and individual measurement points of the Lawrence Livermore National Laboratory phantom and its overlay plates in the regions covered by these detectors were provided by the manufacturer. Germanium detectors are of a different size and are placed in different locations on the phantom so that the manufacturer`s data are no longer applicable for the locations of the germanium detectors on the phantom. The Human Monitoring Laboratory has re-evaluated the chest wall thickness of both the Lawrence Livermore National Laboratory and Japanese Atomic Energy Research Institute phantoms and their overlay plates for its germanium lung counting system. The measurements were made in the upper right, lower right, upper left, and lower left positions on the phantom`s torso plate above the lungs. The effective chest wall thicknesses (17 keV) for the Lawrence Livermore National Laboratory torso plate are 1.46 cm, 1.43 cm, 1.66 cm, 1.48 cm, respectively. The manufacturer`s quoted average effective chest wall thickness for a pair of phoswich detectors is 1.63 cm. The measured effective chest wall thicknesses (17 keV) for the JAERI`s torso plate are 1.76 cm, 2.15 cm, 1.79 cm, 2.15 cm, respectively. The manufacturer`s quoted average chest wall thickness for an unspecified region of the chest is 1.50 cm. This paper presents effective chest wall thickness data for the phantoms with and without their overlay plates at 17 keV, 60 keV, 200 keV and 1,500 keV. 13 refs., 2 figs., 4 tabs.

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

    PubMed Central

    Baliga, Mithra

    2016-01-01

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

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

    PubMed

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

    2015-09-01

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

  5. A case of the vacuum phenomenon as a mechanism of gas production in the abdominal wall.

    PubMed

    Mishima, Kentaro; Omori, Kazuhiko; Ohsaka, Hiromichi; Takeda, Jun; Ishikawa, Kouhei; Obinata, Mariko; Oode, Yasumasa; Sugita, Manabu; Yanagawa, Youichi

    2015-06-01

    A 40-year-old man experienced a collision with a car while driving a motorcycle in which the car was in the opposite lane and made a right turn. The patient was thrown approximately 10 m from the point of collision and, as he exhibited a consciousness disturbance, was transferred to our department. He had a score of 13 on the Glasgow Coma Scale with sinus tachycardia on arrival. He showed guarding of the abdomen. A pan scan disclosed traumatic subarachnoid hemorrhage, intraventricular hemorrhage, fractures of the atlas, thoracic spine, sternum and left femur, and gas in the abdomen located just in front of the stomach. As the gas in the abdomen was initially judged to be free air, the patient underwent emergency laparotomy. However, no signs of perforation or injury were detected throughout the entire digestive tract. The accumulation of minute gas (vacuum phenomenon) occurs as traumatic impact. As representative mimics of free air were not observed during surgery in the present case, we believe that the traumatic impact to the patient's abdomen as a result of the collision caused the accumulation of gas in the abdominal wall due to vacuum phenomenon. Physicians should be aware of this clinical entity to accurately recognize the mechanism of gas formation in patients showing negative laparotomy findings for gas in the abdomen. This unique case adds additional information regarding the documented etiologies of mimics of pneumoperitoneum. PMID:25600235

  6. 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

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

    PubMed

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

    2012-01-01

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

  8. Surface plasmon and photonic mode propagation in gold nanotubes with varying wall thickness

    SciTech Connect

    Kohl, Jesse; Fireman, Micha; O'Carroll, Deirdre M.

    2011-12-15

    Gold nanotube arrays are synthesized with a range of wall thicknesses (15 to >140 nm) and inner diameters of {approx}200 nm using a hard-template method. A red spectral shift (>0.39 eV) with decreasing wall thickness is observed in dark-field spectra of nanotube arrays and single nanowire/nanotube heterostructures. Finite-difference-time-domain simulations show that nanotubes in this size regime support propagating surface plasmon modes as well as surface plasmon ring resonances at visible wavelengths (the latter is observed only for excitation directions normal to the nanotube long axis with transverse polarization). The energy of the surface plasmon modes decreases with decreasing wall thickness and is attributed to an increase in mode coupling between propagating modes in the nanotube core and outer surface and the circumference dependence of ring resonances. Surface plasmon mode propagation lengths for thicker-walled tubes increase by a factor of {approx}2 at longer wavelengths (>700 nm), where ohmic losses in the metal are low, but thinner-walled tubes (30 nm) exhibit a more significant increase in surface plasmon propagation length (by a factor of more than four) at longer wavelengths. Additionally, nanotubes in this size regime support a photonic mode in their core, which does not change in energy with changing wall thickness. However, photonic mode propagation length is found to decrease for optically thin walls. Finally, correlations are made between the experimentally observed changes in dark-field spectra and the changes in surface plasmon mode properties observed in simulations for the various gold nanotube wall thicknesses and excitation conditions.

  9. Multimodal optical measurement in vitro of surface deformations and wall thickness of the pressurized aortic arch.

    PubMed

    Genovese, Katia; Humphrey, Jay D

    2015-04-01

    Computational modeling of arterial mechanics continues to progress, even to the point of allowing the study of complex regions such as the aortic arch. Nevertheless, most prior studies assign homogeneous and isotropic material properties and constant wall thickness even when implementing patient-specific luminal geometries obtained from medical imaging. These assumptions are not due to computational limitations, but rather to the lack of spatially dense sets of experimental data that describe regional variations in mechanical properties and wall thickness in such complex arterial regions. In this work, we addressed technical challenges associated with in vitro measurement of overall geometry, full-field surface deformations, and regional wall thickness of the porcine aortic arch in its native anatomical configuration. Specifically, we combined two digital image correlation-based approaches, standard and panoramic, to track surface geometry and finite deformations during pressurization, with a 360-deg fringe projection system to contour the outer and inner geometry. The latter provided, for the first time, information on heterogeneous distributions of wall thickness of the arch and associated branches in the unloaded state. Results showed that mechanical responses vary significantly with orientation and location (e.g., less extensible in the circumferential direction and with increasing distance from the heart) and that the arch exhibits a nearly linear increase in pressure-induced strain up to 40%, consistent with other findings on proximal porcine aortas. Thickness measurements revealed strong regional differences, thus emphasizing the need to include nonuniform thicknesses in theoretical and computational studies of complex arterial geometries. PMID:25867620

  10. Multimodal optical measurement in vitro of surface deformations and wall thickness of the pressurized aortic arch

    NASA Astrophysics Data System (ADS)

    Genovese, Katia; Humphrey, Jay D.

    2015-04-01

    Computational modeling of arterial mechanics continues to progress, even to the point of allowing the study of complex regions such as the aortic arch. Nevertheless, most prior studies assign homogeneous and isotropic material properties and constant wall thickness even when implementing patient-specific luminal geometries obtained from medical imaging. These assumptions are not due to computational limitations, but rather to the lack of spatially dense sets of experimental data that describe regional variations in mechanical properties and wall thickness in such complex arterial regions. In this work, we addressed technical challenges associated with in vitro measurement of overall geometry, full-field surface deformations, and regional wall thickness of the porcine aortic arch in its native anatomical configuration. Specifically, we combined two digital image correlation-based approaches, standard and panoramic, to track surface geometry and finite deformations during pressurization, with a 360-deg fringe projection system to contour the outer and inner geometry. The latter provided, for the first time, information on heterogeneous distributions of wall thickness of the arch and associated branches in the unloaded state. Results showed that mechanical responses vary significantly with orientation and location (e.g., less extensible in the circumferential direction and with increasing distance from the heart) and that the arch exhibits a nearly linear increase in pressure-induced strain up to 40%, consistent with other findings on proximal porcine aortas. Thickness measurements revealed strong regional differences, thus emphasizing the need to include nonuniform thicknesses in theoretical and computational studies of complex arterial geometries.

  11. Study of Intrusion Bending for Steel Tubes with Thin Wall Thickness

    NASA Astrophysics Data System (ADS)

    Naoi, Hisashi; Kitakami, Naoki; Mizumura, Masaaki; Kuriyama, Yukihisa

    2008-06-01

    In regard to light-weight structural members for automobiles, attention to hydroforming has been increasing. Intrusion-bending method is well suited to the preliminary bending of hydroformed structural members of automobiles, because straight tubes can be bent into three-dimensional forms by this new method. However, in the case of tubes with a thin wall thickness, wrinkling remains a problem. In this report, application of intrusion bending method to tubes with extremely low ratios of wall thickness to outer diameter (from 1.2 to 1.9%), and whose steel grades are SSPDX, SAFC440R, and SAFC590T was investigated. A summary of this study is as follows. Effects of steel grades and wall thickness ratios on wrinkle formation, eccentricity, and ovality are studied. Relationships between wrinkle generation and gyro movement are investigated.

  12. Use of a pre-expanded "propeller" deep inferior epigastric perforator (DIEP) flap for a large abdominal wall defect.

    PubMed

    Cheng, Angela; Saint-Cyr, Michel

    2013-06-01

    Large abdominal wall soft tissue defects are traditionally reconstructed using loco-regional flaps and/or tissue expanders. Pedicled perforator flaps offer similar tissue coverage with minimal donor site morbidity and do not require microsurgical skills. The deep inferior epigastric perforator (DIEP) flap has become increasingly popular for breast reconstruction and offers abundant soft tissue while permitting primary donor site closure. To minimize operative sessions, recovery time, donor site morbidity, and avoid microsurgery, we combined tissue expansion with a "propeller" flap design and report this first case of a pre-expanded pedicled perforator flap based on the DIEP to address a large abdominal wall defect due to a burn injury. PMID:23031631

  13. Patient-specific models of wall stress in abdominal aortic aneurysm: a comparison between MR and CT

    NASA Astrophysics Data System (ADS)

    de Putter, Sander; Breeuwer, Marcel; van de Vosse, Frans N.; Kose, Ursula; Gerritsen, Frans A.

    2006-03-01

    Finite element method based patient-specific wall stress in abdominal aortic aneurysm (AAA) may provide a more accurate rupture risk predictor than the currently used maximum transverse diameter. In this study, we have investigated the sensitivity of the wall stress in AAA with respect to geometrical variations. We have acquired MR and CT images for four patients with AAA. Three individual users have delineated the AAA vessel wall contours on the image slices. These contours were used to generate synthetic feature images for a deformable model based segmentation method. We investigated the reproducibility and the influence of the user variability on the wall stress. For sufficiently smooth models of the AAA wall, the peak wall stress is reproducible for three out of the four AAA geometries. The 0.99 percentiles of the wall stress show excellent reproducibility for all four AAAs. The variations induced by user variability are larger than the errors caused by the segmentation variability. The influence of the user variability appears to be similar for MR and CT. We conclude that the peak wall stress in AAA is sensitive to small geometrical variations. To increase reproducibility it appears to be best not to allow too much geometrical detail in the simulations. This could be achieved either by using a sufficiently smooth geometry representation or by using a more robust statistical parameter derived from the wall stress distribution.

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

    PubMed

    Gasymov, E M

    2005-01-01

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

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

    SciTech Connect

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

    2010-06-15

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

  16. Efficacy of antimicrobial triclosan-coated polyglactin 910 (Vicryl* Plus) suture for closure of the abdominal wall after colorectal surgery.

    PubMed

    Rasić, Zarko; Schwarz, Dragan; Adam, Visnja Nesek; Sever, Marko; Lojo, Nermin; Rasić, Domagoj; Matejić, Tomislav

    2011-06-01

    This study compared Triclosan coated polyglactin 910 (Vicryl* Plus) with polyglactin 910 (Vicryl*) on abdominal wall healing in colorectal surgery patients. 184 patients with colorectal cancer were included in the study. In 91, the abdominal wall was closed with the Vicryl* Plus, and in 93 patients with Vicryl*. Demographic characteristics, biochemical inflammatory parameters, wound appearance, length of hospital stay, postoperative wound complications and post-incisional hernia were recorded. In the Vicryl* Plus group there was a shorter hospital stay (13.2 +/- 1.3 days; 21.4 +/- 2.8 respectively). In the Vicryl* Plus group inflammatory parameters decreased to normal within the first week whereas in the Vicryl* group remained increased. In the Vicryl* Plus group four patients had a wound discharge, seven had inflammatory reactions to the skin sutures. One dehiscence was noticed. In the Vicryl* group 12 patients had an SSI, 14 patients had inflammatory reactions to the skin sutures and 7 patients had a wound dehiscence. Closure of the abdominal wall using Vicryl* Plus decreases postoperative wound complications, length of hospital stay and is associated with a more rapid return of inflammatory markers to normal. PMID:21755716

  17. High Reproducibility of Adhesion Formation in Rat with Meso-Stitch Approximation of Injured Cecum and Abdominal Wall

    PubMed Central

    Poehnert, Daniel; Abbas, Mahmoud; Kreipe, Hans-Heinrich; Klempnauer, Juergen; Winny, Markus

    2015-01-01

    Objective: Peritoneal adhesions following surgery are a common, serious pathology with severe complications. Appropriate animal adhesion models are essential for the assessment of adhesion preventing medical devices. This study introduces a variation of an established rat model in which highest degree adhesions are induced with excellent reproducibility (OPAM = optimized peritoneal adhesion model). Thus, this model seems to be eligible to study effects of adhesion preventing devices. Methods: 24 Lewis male rats were divided into four groups (OPAM, WSFX, sham-OPAM, sham-WSFX). The OPAM technique comprised cecal abrasion, creation of an abdominal wall defect plus approximation of injured areas by a suture, which was compared to a setting of lesions without suture fixation (WSFX). All rats were sacrificed at day 7. Macroscopic and histopathological evaluations were performed. Results were statistically analyzed using ANOVA and Dunnett's test. Results: In OPAM rats macroscopic analyses revealed a 90% incidence adhesion of cecum to the abdominal wall, all adhesions imposing as complete agglutination. In WSFX animals incidence of adhesions formation was 75%, while in both sham groups there were no adhesions at all. Histology showed the structure of adhesions with merged smooth muscle of colon and skeletal muscle of abdominal wall in all cases. Conclusion: OPAM technique provides adhesions of injured areas with a better probability than with conventional methods. All OPAM adhesions impressed as highest degree adhesions, i.e. agglutination. Due to high reproducibility in incidence and extend of adhesion formation, the OPAM is recommended for testing of adhesion prevention medical devices. PMID:25552912

  18. An exact solution for a thick domain wall in general relativity

    NASA Technical Reports Server (NTRS)

    Goetz, Guenter; Noetzold, Dirk

    1989-01-01

    An exact solution of the Einstein equations for a static, planar domain wall with finite thickness is presented. At infinity, density and pressure vanish and the space-time tends to the Minkowski vacuum on one side of the wall and to the Taub vacuum on the other side. A surprising feature of this solution is that the density and pressure distribution are symmetric about the central plane of the wall whereas the space-time metric and therefore also the gravitational field experienced by a test particle is asymmetric.

  19. Thermal Marangoni instability of a thin film flowing down a thick wall deformed in the backside

    NASA Astrophysics Data System (ADS)

    Dávalos-Orozco, L. A.

    2016-05-01

    The nonlinear instability of a thin liquid film flowing down a heated thick wall with deformations in the backside is investigated. Here it is assumed that the wall deformations are sinusoidal in space. Time dependent perturbations are imposed at the origin of the free surface of the film. It is found that the wall deformations have an important influence on the flow instability. Moreover, it is shown that the free surface has a large amplitude spatial response to the backside deformations of the wall. This response increases its amplitude considerably when decreasing the wall spatial wavelength down to the wavelength of the time dependent perturbations. At that point, numerical analysis reveals that the time dependent perturbations in some cases are almost impossible to observe on the free surface response. However, in other cases, their interaction produces large amplitude nonlinear wave modulations.

  20. Imaging vessel wall biology to predict outcome in abdominal aortic aneurysm

    PubMed Central

    Golestani, Reza; Razavian, Mahmoud; Nie, Lei; Zhang, Jiasheng; Jung, Jae-Joon; Ye, Yunpeng; de Roo, Michelle; Hilgerink, Koen; Liu, Chi; Robinson, Simon P.; Sadeghi, Mehran M.

    2014-01-01

    Background Abdominal aortic aneurysm (AAA) rupture risk is currently determined based on size and symptoms. This approach does not address the rupture risk associated with small aneurysms. Given the role of matrix metalloproteinases (MMPs) in AAA weakening and rupture, we investigated the potential of MMP-targeted imaging for detection of aneurysm biology and prediction of outcome in a mouse model of AAA with spontaneous rupture. Methods and Results Fifteen week-old mice (n=66) were infused with angiotensin II for four weeks to induce AAA. Saline-infused mice (n=16) served as control. The surviving animals underwent in vivo MMP-targeted microSPECT/CT imaging, using RP805, a 99mTc-labeled MMP-specific tracer, followed by ex vivo planar imaging, morphometry and gene expression analysis. RP805 uptake in suprarenal aorta on microSPECT images was significantly higher in animals with AAA, as compared with angiotensin II-infused animals without AAA or control animals. CD68 expression and MMP activity were increased in AAA and significant correlations were noted between RP805 uptake and CD68 expression or MMP activity, but not aortic diameter. A group of angiotensin II-infused animals (n=24) were imaged at 1 week and were followed for an additional three weeks. RP805 uptake in suprarenal aorta at 1 week was significantly higher in mice that later developed rupture/AAA. Furthermore, tracer uptake at 1 week correlated with aortic diameter at 4 weeks. Conclusions MMP-targeted imaging reflects vessel wall inflammation and can predict future aortic expansion or rupture in murine AAA. If confirmed in humans, this may provide a new paradigm for AAA risk stratification. PMID:25550400

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

    PubMed

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

    2015-04-01

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

  2. A successful early gore-tex reconstruction of an abdominal wall defect in a neonate with Cantrell pentalogy: a case report and literature review.

    PubMed

    Divkovic, Dalibor; Kvolik, Slavica; Sipl, Mirna; Sego, Krunoslav; Puseljic, Silvija; Rakipovic-Stojanovic, Andreja; Kovacic, Borna

    2015-01-01

    A surgical technique, materials used for abdominal wall reconstruction, and postoperative care are important for patient outcomes. We report the first case of neonate with Cantrell's pentalogy surviving early reconstruction of abdominal, diaphragmal and pericardial defects. Several recent investigations suggest that intraabdominal pressure monitoring may improve outcomes in this patient category. PMID:25678967

  3. Magnet Fall inside a Conductive Pipe: Motion and the Role of the Pipe Wall Thickness

    ERIC Educational Resources Information Center

    Donoso, G.; Ladera, C. L.; Martin, P.

    2009-01-01

    Theoretical models and experimental results are presented for the retarded fall of a strong magnet inside a vertical conductive non-magnetic tube. Predictions and experimental results are in good agreement modelling the magnet as a simple magnetic dipole. The effect of varying the pipe wall thickness on the retarding magnetic drag is studied for

  4. Boll wall thickness in four cotton species and susceptibility to stink bug feeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae), adults can introduce pathogens into cotton bolls while feeding. Stylet penetration estimates of southern green stink bugs are known, and knowledge of boll wall thickness in cotton species may aid in determining susceptibility...

  5. Magnet Fall inside a Conductive Pipe: Motion and the Role of the Pipe Wall Thickness

    ERIC Educational Resources Information Center

    Donoso, G.; Ladera, C. L.; Martin, P.

    2009-01-01

    Theoretical models and experimental results are presented for the retarded fall of a strong magnet inside a vertical conductive non-magnetic tube. Predictions and experimental results are in good agreement modelling the magnet as a simple magnetic dipole. The effect of varying the pipe wall thickness on the retarding magnetic drag is studied for…

  6. Delayed primary closure of contaminated abdominal wall defects with non-crosslinked porcine acellular dermal matrix compared with conventional staged repair: a retrospective study

    PubMed Central

    2014-01-01

    Introduction Synthetic mesh has been used traditionally to repair abdominal wall defects, but its use is limited in the case of bacterial contamination. New biological materials are now being used successfully for delayed primary closure of contaminated abdominal wall defects. The costs of biological materials may prevent surgeons from using them. We compared the conventional staged repair of contaminated abdominal wall defects with a single-stage procedure using a non-crosslinked porcine acellular dermal matrix. Methods A total of 14 cases with Grade 3 contaminated abdominal wall defects underwent delayed primary closure of the abdomen using a non-crosslinked porcine acellular dermal matrix (Strattice Reconstructive Tissue Matrix, LifeCell Corp., Branchburg, NJ, USA). The results were compared with a group of 14 patients who had received conventional treatment for the repair of contaminated abdominal wall defects comprising a staged repair during two separate hospital admissions employing synthetic mesh. Treatment modalities, outcomes, and costs were compared. Results In all cases treated with delayed primary closure employing non-crosslinked porcine acellular dermal matrix, there were no complications related to its use. Two patients died due to unrelated events. Although treatment costs were estimated to be similar in the two groups, the patients treated with porcine acellular dermal matrix spent less time as an inpatient than those receiving conventional two-stage repair. Conclusions Delayed primary closure of contaminated abdominal wall defects using a non-crosslinked porcine acellular dermal matrix may be a suitable alternative to conventional staged repair. In our patients, it resulted in early restoration of abdominal wall function and shorter hospitalization. The costs for treating contaminated abdominal wall defects using porcine acellular dermal matrix during a single hospital admission were not higher than costs for conventional two-stage repair. Further randomized studies are needed to expand upon these findings. PMID:25015374

  7. Repair of Abdominal Wall Defects In Vitro and In Vivo Using VEGF Sustained-Release Multi-Walled Carbon Nanotubes (MWNT) Composite Scaffolds

    PubMed Central

    Yang, Jianjun; Liu, Zhengni; Peng, Zhiyou; Tang, Rui; Gu, Yan

    2013-01-01

    Objective Porcine acellular dermal matrices (ADM) have been widely used in experimental and clinical research for abdominal wall repair. Compared to porcine small intestinal submucosa (SIS), the effect of these matrices on the regenerative capacity of blood vessels is still not ideal. Multi-walled carbon nanotubes (MWNTs) can more effectively transport VEGF to cells or tissues because of their large specific surface area and interior cavity. In this study, we explored the safety and efficacy of implanted VEGF-loaded MWNT composite scaffolds in vitro and vivo to repair abdominal wall defects. Materials and Methods VEGF-loaded MWNTs were prepared by a modified plasma polymerization treatment. Four composite scaffolds were evaluated for cytotoxicity, proliferation, and release dynamics. We created 3 cm4 cm abdominal wall defects in 43 Sprague-Dawley rats. After implantation times of 2, 4, 8, and 12 weeks, the scaffolds and the surrounding tissues were collected and examined by gross inspection, biomechanical testing, and histological examination. Results A 510 nm poly(lactic-co-glycolic acid) (PLGA) film was evenly distributed on MWNTs. The 3% MWNT composite group showed lower cytotoxicity and appropriate release performance, and it was thus tested in vivo. In rats with the 3% composite implanted, host cells were prevented from migrating to the ADM at 2 weeks, vascularization was established more rapidly at 12 weeks, and the values for both the maximum load and the elastic modulus were significantly lower than in the ADM-alone group (p<0.01). Histological staining revealed that the MWNT was still not completely eliminated 12 weeks after implantation. Conclusion MWNTs were able to carry VEGF to cells or tissues, and the 3% MWNT composite material showed lower cytotoxicity and had an appropriate release performance, which prompted faster vascularization of the ADM than other scaffolds. Nevertheless, the MWNTs induced harmful effects that should be carefully considered in biomedical studies. PMID:23717603

  8. Real-time dielectric-film thickness measurement system for plasma processing chamber wall monitoring

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Yong; Chung, Chin-Wook

    2015-12-01

    An in-situ real-time processing chamber wall monitoring system was developed. In order to measure the thickness of the dielectric film, two frequencies of small sinusoidal voltage (˜1 V) signals were applied to an electrically floated planar type probe, which is positioned at chamber wall surface, and the amplitudes of the currents and the phase differences between the voltage and current were measured. By using an equivalent sheath circuit model including a sheath capacitance, the dielectric thickness can be obtained. Experiments were performed in various plasma condition, and reliable dielectric film thickness was obtained regardless of the plasma properties. In addition, availability in commercial chamber for plasma enhanced chemical vapor deposition was verified. This study is expected to contribute to the control of etching and deposition processes and optimization of periodic maintenance in semiconductor manufacturing process.

  9. Real-time dielectric-film thickness measurement system for plasma processing chamber wall monitoring.

    PubMed

    Kim, Jin-Yong; Chung, Chin-Wook

    2015-12-01

    An in-situ real-time processing chamber wall monitoring system was developed. In order to measure the thickness of the dielectric film, two frequencies of small sinusoidal voltage (∼1 V) signals were applied to an electrically floated planar type probe, which is positioned at chamber wall surface, and the amplitudes of the currents and the phase differences between the voltage and current were measured. By using an equivalent sheath circuit model including a sheath capacitance, the dielectric thickness can be obtained. Experiments were performed in various plasma condition, and reliable dielectric film thickness was obtained regardless of the plasma properties. In addition, availability in commercial chamber for plasma enhanced chemical vapor deposition was verified. This study is expected to contribute to the control of etching and deposition processes and optimization of periodic maintenance in semiconductor manufacturing process. PMID:26724022

  10. Chest wall thickness measurements and the dosimetric implications for male workers in the uranium industry.

    PubMed

    Kramer, G H; Hauck, B M; Allen, S A

    2001-01-01

    The Human Monitoring Laboratory has measured the chest wall thickness and adipose mass fraction of a group of workers at a Canadian uranium refinery, a conversion plant, and a fuel fabrication site using ultrasound. A site-specific biometric equation has been developed for these workers, who seem to be somewhat larger than other workers reported in the literature. Chest wall thickness is a very important modifier on lung counting efficiency and these data have been put into the perspective of the impending Canadian dose limits that will reduce the limit of occupationally exposed workers to 100 mSv in a 5-y period with a maximum of 50 mSv in any one year. The sensitivity of the germanium and phoswich based lung counting systems have been compared. Over a range of chest wall thickness of 1.6 cm to 6.0 cm and using a 30-min counting time, the achievable MDA's lie in the range of 6.7 mg to 19.1 mg or 6.7 mg to 30 mg with a two-phoswich-detector array or a germanium lung counting system, respectively. Depending on chest wall thickness, these achievable MDA's are close to, or exceed, the predicted amounts of natural uranium that will remain in the lung (absorption type M and S) after an intake equivalent to the Annual Limit on Intake that corresponds to 20 mSv. Neither system is sufficiently sensitive to detect an intake of Type S natural uranium in a worker with a chest wall thickness that corresponds to the average (3.73 cm) if it occurred more than 7 d prior to the lung count. PMID:11204122

  11. Effect of wall thickness on measurement of dose for high energy neutrons.

    PubMed

    Perez-Nunez, Delia; Braby, Leslie A

    2010-01-01

    Neutrons produced from the interaction between galactic cosmic rays and spacecraft materials are responsible for a very important portion of the dose received by astronauts. The neutron energy spectrum depends on the incident charged particle spectrum and the scattering environment but generally extends to beyond 100 MeV. Tissue-equivalent proportional counters (TEPC) are used to measure the dose during the space mission, but their weight and size are very important factors for their design and construction. To achieve ideal neutron dosimetry, the wall thickness should be at least the range of a proton having the maximum energy of the neutrons to be monitored. This proton range is 0.1 cm for 10 MeV neutrons and 7.6 cm for 100 MeV neutrons. A 7.6 cm wall thickness TEPC would provide charged particle equilibrium (CPE) for neutrons up to 100 MeV, but for space applications it would not be reasonable in terms of weight and size. In order to estimate the errors in measured dose due to absence of CPE, MCNPX simulations of energy deposited by 10 MeV and 100 MeV neutrons in sites with wall thickness between 0.1 cm and 8.5 cm were performed. The results for 100 MeV neutrons show that energy deposition per incident neutron approaches a plateau as the wall thickness approaches 7.6 cm. For the 10 MeV neutrons, energy deposition per incident neutron decreases as the wall thickness increases above 0.1 cm due to attenuation. PMID:19959949

  12. Quantification of esophageal wall thickness in CT using atlas-based segmentation technique

    NASA Astrophysics Data System (ADS)

    Wang, Jiahui; Kang, Min Kyu; Kligerman, Seth; Lu, Wei

    2015-03-01

    Esophageal wall thickness is an important predictor of esophageal cancer response to therapy. In this study, we developed a computerized pipeline for quantification of esophageal wall thickness using computerized tomography (CT). We first segmented the esophagus using a multi-atlas-based segmentation scheme. The esophagus in each atlas CT was manually segmented to create a label map. Using image registration, all of the atlases were aligned to the imaging space of the target CT. The deformation field from the registration was applied to the label maps to warp them to the target space. A weighted majority-voting label fusion was employed to create the segmentation of esophagus. Finally, we excluded the lumen from the esophagus using a threshold of -600 HU and measured the esophageal wall thickness. The developed method was tested on a dataset of 30 CT scans, including 15 esophageal cancer patients and 15 normal controls. The mean Dice similarity coefficient (DSC) and mean absolute distance (MAD) between the segmented esophagus and the reference standard were employed to evaluate the segmentation results. Our method achieved a mean Dice coefficient of 65.55 ± 10.48% and mean MAD of 1.40 ± 1.31 mm for all the cases. The mean esophageal wall thickness of cancer patients and normal controls was 6.35 ± 1.19 mm and 6.03 ± 0.51 mm, respectively. We conclude that the proposed method can perform quantitative analysis of esophageal wall thickness and would be useful for tumor detection and tumor response evaluation of esophageal cancer.

  13. Detection of Cardiac Function Abnormality from MRI Images Using Normalized Wall Thickness Temporal Patterns

    PubMed Central

    Wael, Mai; Fahmy, Ahmed S.

    2016-01-01

    Purpose. To develop a method for identifying abnormal myocardial function based on studying the normalized wall motion pattern during the cardiac cycle. Methods. The temporal pattern of the normalized myocardial wall thickness is used as a feature vector to assess the cardiac wall motion abnormality. Principal component analysis is used to reduce the feature dimensionality and the maximum likelihood method is used to differentiate between normal and abnormal features. The proposed method was applied on a dataset of 27 cases from normal subjects and patients. Results. The developed method achieved 81.5%, 85%, and 88.5% accuracy for identifying abnormal contractility in the basal, midventricular, and apical slices, respectively. Conclusions. A novel feature vector, namely, the normalized wall thickness, has been introduced for detecting myocardial regional wall motion abnormality. The proposed method provides assessment of the regional myocardial contractility for each cardiac segment and slice; therefore, it could be a valuable tool for automatic and fast determination of regional wall motion abnormality from conventional cine MRI images. PMID:27034648

  14. Effects of the Transient Blood Flow-Wall Interaction on the Wall Stress Distribution in Abdominal Aortic Aneurysm (AAA)

    NASA Astrophysics Data System (ADS)

    Tang, Rubing; Geindreau, Christian; Lasheras, Juan

    2006-11-01

    Our static finite element analysis (FEA) of both idealized and real clinical models has shown that the maximum diameter and asymmetry have substantial influence on the AAA wall stress distribution. The thrombus inside the AAA was also found to reduce the magnitude of the wall stresses. To achieve a better understanding of the wall stress distribution in real AAAs, a dynamic FEA was also performed. We considered models, both symmetric and non-symmetric, in which the aorta is assumed isotropic with nonlinear material properties. For the limiting case of rigid walls, the evolution of the flow pattern and the wall shear stresses due to fluid flow at different stages of cardiac cycle predicted by our simulations are compared with experimental results obtained in in-vitro models. A good agreement is found between both results. Finally, we have extended the analysis to the physiologically correct case of deformable walls and characterized the transient effects on the wall stresses.

  15. Distribution of ice thickness and subglacial topography of the "Chinese Wall" around Kunlun Station, East Antarctica

    NASA Astrophysics Data System (ADS)

    Cui, Xiang-Bin; Sun, Bo; Su, Xiao-Gang; Guo, Jing-Xue

    2016-03-01

    As fundamental parameters of the Antarctic Ice Sheet, ice thickness and subglacial topography are critical factors for studying the basal conditions and mass balance in Antarctica. During CHINARE 24 (the 24th Chinese National Antarctic Research Expedition, 2007/08), the research team used a deep ice-penetrating radar system to measure the ice thickness and subglacial topography of the "Chinese Wall" around Kunlun Station, East Antarctica. Preliminary results show that the ice thickness varies mostly from 1600 m to 2800 m along the "Chinese Wall", with the thickest ice being 3444 m, and the thinnest ice 1255 m. The average bedrock elevation is 1722 m, while the minimum is just 604 m. Compared with the northern side of the ice divide, the ice thickness is a little greater and the subglacial topography lower on the southern side, which is also characterized by four deep valleys. We found no basal freeze-on ice in the Gamburtsev Subglacial Mountains area, subglacial lakes, or water bodies along the "Chinese Wall". Ice thickness and subglacial topography data extracted from the Bedmap 2 database along the "Chinese Wall" are consistent with our results, but their resolution and accuracy are very limited in areas where the bedrock fluctuates intensely. The distribution of ice thickness and subglacial topography detected by ice-penetrating radar clarifies the features of the ice sheet in this "inaccessible" region. These results will help to advance the study of ice sheet dynamics and the determination of future locations of the GSM's geological and deep ice core drilling sites in the Dome A region.

  16. Effective Wall Thickness of Single-Walled Carbon Nanotubes for Multi-Scale Analysis: The Problem and a Possible Solution

    NASA Astrophysics Data System (ADS)

    Zhang, L. C.; Wang, C. Y.

    Continuum mechanics models have been used to characterize the mechanical behaviour of carbon nanotubes, but their validity down to the nanometer scale has not been fully verified. A typical example is the effective wall thickness of single-walled carbon nanotubes (SWCNTs), which has not been well defined after years of effort. This paper proposes a sufficient condition for determining the effective wall thickness h and Young's modulus E of an SWCNT using in-plane stiffness, K in-plane, torsion stiffness, D torsion, bending stiffness, D bending, and off-plane torsion stiffness, K torsion, as the independent elastic constants of a continuum model. The paper concludes that when the Vodenitcharova-Zhang's necessary condition and D bending/K in-plane = D torsion/K torsion are satisfied, the intersect of D bending and K in-plane curves in the E-h plane will determine a unique h, and in turn, leads to a defined E. For SWCNT (10, 10), h≈ 0.1 nmandE≈3.5TPa.

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

    PubMed Central

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

    2015-01-01

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

  18. Unusual aetiology of abdominal wall abscess: cholecystocutaneous fistula presenting 20 years after open subtotal cholecystectomy.

    PubMed

    Maynard, William; McGlone, Emma Rose; Deguara, Jean

    2016-01-01

    A 68-year-old woman presented to the emergency department, with an abscess in the right upper anterior abdominal wall. She had a medical history of an open cholecystectomy 20 years prior, diabetes, obesity and a laparotomy for perforated sigmoid diverticular disease complicated by a large parastomal hernia. CT revealed this subcutaneous abscess to track intra-abdominally through the liver and communicate with the gallbladder fossa. The abscess was incised and drained. The wound initially drained pus, and then bile. Magnetic resonance cholangiopancreatogram (MRCP) demonstrated a remnant gallbladder containing 2 gallstones, a cholecystocutaneous fistula, portal vein thrombosis and cavernous transformation of the bile duct. The patient improved and was discharged. The patient's case history and imaging were discussed with the tertiary referral centre, in a multidisciplinary team. After an extensive and balanced discussion, the patient declined a completion cholecystectomy and continues to have occasional discharge from the fistula in her right upper quadrant. PMID:27033283

  19. Bladder wall thickness in the assessment of neurogenic bladder: a translational discussion of current clinical applications

    PubMed Central

    Sturm, Renea M.

    2016-01-01

    The prospective trial by Kim et al. “Can Bladder Wall Thickness Predict Videourodynamic Findings in Children with Spina Bifida?” published in Journal of Urology investigated the measurement of bladder wall thickness (BWT) as a non-invasive assessment tool for lower urinary tract changes in neurogenic bladder (NGB). In this study, no significant association was observed between BWT and high-risk urodynamic parameters. This editorial discusses the basic science of bladder wall thickening as well as prior studies relating wall thickness to clinical parameters. Although Kim et al. provide a unique literature contribution in terms of assessment of BWT at defined percent cystometric capacity, specific aspects of study methodology and population may have contributed to a lack of correlation with high-risk urodynamic findings. The application of non-invasive modalities to lower urinary tract assessment of NGB remains a promising and relevant area of future research to prevent progression to end stage lower urinary tract changes for all individuals with spina bifida. PMID:26889485

  20. Bladder wall thickness in the assessment of neurogenic bladder: a translational discussion of current clinical applications.

    PubMed

    Sturm, Renea M; Cheng, Earl Y

    2016-01-01

    The prospective trial by Kim et al. "Can Bladder Wall Thickness Predict Videourodynamic Findings in Children with Spina Bifida?" published in Journal of Urology investigated the measurement of bladder wall thickness (BWT) as a non-invasive assessment tool for lower urinary tract changes in neurogenic bladder (NGB). In this study, no significant association was observed between BWT and high-risk urodynamic parameters. This editorial discusses the basic science of bladder wall thickening as well as prior studies relating wall thickness to clinical parameters. Although Kim et al. provide a unique literature contribution in terms of assessment of BWT at defined percent cystometric capacity, specific aspects of study methodology and population may have contributed to a lack of correlation with high-risk urodynamic findings. The application of non-invasive modalities to lower urinary tract assessment of NGB remains a promising and relevant area of future research to prevent progression to end stage lower urinary tract changes for all individuals with spina bifida. PMID:26889485

  1. The effect of fig wall thickness in Ficus erecta var. beecheyana on parasitism

    NASA Astrophysics Data System (ADS)

    Tzeng, Hsy-Yu; Ou, Chern-Hsiung; Lu, Fu-Yuan; Bain, Anthony; Chou, Lien-Siang; Kjellberg, Finn

    2014-05-01

    Fig wasp communities constitute a model system to analyse determinants of community complexity and to investigate how biological interaction networks are maintained. It has been suggested for monoecious figs, that fig pollinating wasps avoid ovipositing in flowers located close to the fig wall because of strong parasitic pressure by wasps ovipositing through the fig wall. This behaviour could help explain why mainly seeds are produced in flowers located close to the fig wall, thus stabilizing the fig-pollinating wasp mutualism. In this contribution we explore, for dioecious figs, whether ovipositor length of parasitic species may really be limiting. In dioecious figs, functionally male figs produce pollinating wasps and pollen while female figs produce only seeds, facilitating selection of traits favouring pollinator reproduction in male figs. We show in Ficus erecta that fig walls are thicker in male figs than in female figs. Male figs presenting thick walls, thicker than the length of the parasites' ovipositors, went unparasitized while male figs presenting thinner walls were systematically parasitized. Hence, in F. erecta, ovipositor length of the parasites is limiting access to some figs. However, we also show that in another dioecious species, Ficus formosana, presenting thin walled male figs, no fig is protected against oviposition by its two parasites. Hence in dioecious as well as in monoecious figs, in some Ficus species, ovipositors of the parasites are limiting access to ovules, while in other Ficus species all ovules are exposed to parasitism.

  2. Physical modeling of friction conditions on the wall thickness variation during sheet hydroforming

    NASA Astrophysics Data System (ADS)

    Li, Feng; Xu, Peng; Zhang, Xinlong; Liu, Qiang

    2015-05-01

    In order to research the influence of friction conditions on the sheet metal deformation behavior under the fluid pressure, the experimental method that can test the relationship between fluid pressure and wall thickness was proposed in this paper. The theoretical model about the quantitative variation relationship between fluid pressure and wall thickness together with the theoretical model about the quantitative variation relationship between friction coefficient and wall thickness, was obtained by theoretical derivation. At the same time, it could be concluded that friction contact region close to the tensile end was easier to satisfy the plastic yield criterion. Therefore, the plastic deformation initially occurred at this area and fracture emerged on account of excessive reduction of the sheet thickness. Simulation analysis with 304 stainless steel was carried out. The result indicated that the capacity of sheet uniform deformation decreased with the increasing of the friction coefficient. When the friction coefficient increased from 0.08 to 0.20, the uniform elongation decreased by 32%. But when other conditions were kept unchanged, the greater the fluid pressure was, the thinner the sheet would be. Experiments indicated that the necking and fracture appeared in the gauge length near the tensile end with different lubricants. And these provided a theoretical basis for the process and device design of sheet metal hydroforming.

  3. Sex-Related Differences of Cortical Thickness in Patients with Chronic Abdominal Pain

    PubMed Central

    Jiang, Zhiguo; Dinov, Ivo D.; Labus, Jennifer; Shi, Yonggang; Zamanyan, Alen; Gupta, Arpana; Ashe-McNalley, Cody; Hong, Jui-Yang; Tillisch, Kirsten; Toga, Arthur W.; Mayer, Emeran A.

    2013-01-01

    Background & Aims Regional reductions in gray matter (GM) have been reported in several chronic somatic and visceral pain conditions, including irritable bowel syndrome (IBS) and chronic pancreatitis. Reported GM reductions include insular and anterior cingulate cortices, even though subregions are generally not specified. The majority of published studies suffer from limited sample size, heterogeneity of populations, and lack of analyses for sex differences. We aimed to characterize regional changes in cortical thickness (CT) in a large number of well phenotyped IBS patients, taking into account the role of sex related differences. Methods Cortical GM thickness was determined in 266 subjects (90 IBS [70 predominantly premenopausal female] and 176 healthy controls (HC) [155 predominantly premenopausal female]) using the Laboratory of Neuro Imaging (LONI) Pipeline. A combined region of interest (ROI) and whole brain approach was used to detect any sub-regional and vertex-level differences after removing effects of age and total GM volume. Correlation analyses were performed on behavioral data. Results While IBS as a group did not show significant differences in CT compared to HCs, sex related differences were observed both within the IBS and the HC groups. When female IBS patients were compared to female HCs, whole brain analysis showed significant CT increase in somatosensory and primary motor cortex, as well as CT decrease in bilateral subgenual anterior cingulate cortex (sgACC). The ROI analysis showed significant regional CT decrease in bilateral subregions of insular cortex, while CT decrease in cingulate was limited to left sgACC, accounting for the effect of age and GM volume. Several measures of IBS symptom severity showed significant correlation with CT changes in female IBS patients. Conclusions Significant, sex related differences in CT are present in both HCs and in IBS patients. The biphasic neuroplastic changes in female IBS patients are related to symptom severity. PMID:24040118

  4. Elastic analysis of heterogeneous thick-walled spherical pressure vessels with parabolic varying properties

    NASA Astrophysics Data System (ADS)

    Karami, Keyhan; Abedi, Majid; Zamani Nejad, Mohammad; Lotfian, Mohammad Hassan

    2012-12-01

    On the basis of plane elasticity theory (PET), the displacement and stress components in a thick-walled spherical pressure vessels made of heterogeneous materials subjected to internal and external pressure is developed. The mechanical properties except the Poisson's ratio are assumed to obey the parabolic variations throughout the thickness. Effect of material inhomogeneity on the elastic deformations and stresses is investigated. The analytical solutions and the solutions carried out through the FEM have a good agreement. The values used in this study are arbitrary chosen to demonstrate the effect of inhomogeneity on displacements, and stresses distributions.

  5. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output.

    PubMed

    Smerup, Morten; Damkjær, Mads; Brøndum, Emil; Baandrup, Ulrik T; Kristiansen, Steen Buus; Nygaard, Hans; Funder, Jonas; Aalkjær, Christian; Sauer, Cathrine; Buchanan, Rasmus; Bertelsen, Mads Frost; Østergaard, Kristine; Grøndahl, Carsten; Candy, Geoffrey; Hasenkam, J Michael; Secher, Niels H; Bie, Peter; Wang, Tobias

    2016-02-01

    Giraffes - the tallest extant animals on Earth - are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. Arterial pressure may exceed 300 mmHg and has historically been attributed to an exceptionally large heart. Recently, this has been refuted by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It thus remains unexplained how the normal-sized giraffe heart generates such massive arterial pressures. We hypothesized that giraffe hearts have a small intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic pressures to calculate left ventricular wall stress. Cardiac output was also determined by inert gas rebreathing to provide an additional and independent estimate of stroke volume. Echocardiography and inert gas-rebreathing yielded similar cardiac outputs of 16.1±2.5 and 16.4±1.4 l min(-1), respectively. End-diastolic and end-systolic volumes were 521±61 ml and 228±42 ml, respectively, yielding an ejection fraction of 56±4% and a stroke volume of 0.59 ml kg(-1). Left ventricular circumferential wall stress was 7.83±1.76 kPa. We conclude that, relative to body mass, a small left ventricular cavity and a low stroke volume characterizes the giraffe heart. The adaptations result in typical mammalian left ventricular wall tensions, but produce a lowered cardiac output. PMID:26643090

  6. Enhanced film thickness for Nel wall in soft magnetic film by introducing strong magnetocrystalline anisotropy

    NASA Astrophysics Data System (ADS)

    Xu, Fei; Wang, Tao; Ma, Tianyong; Wang, Ying; Zhu, Shimeng; Li, Fashen

    2016-01-01

    This study investigated the magnetic domain walls in a single-layer soft magnetic film with strong magnetocrystalline anisotropy energy. The soft magnetic film is composed of a highly c-axis-oriented hcp-Co81Ir19 alloy with strong negative magnetocrystalline anisotropy. The domain structure of the soft Co81Ir19 films with thickness ranging from 50230?nm in a demagnetization state was observed through magnetic force microscopy and Lorentz transmission electron microscopy. Results reveal that the critical transition thickness at which the domain wall changes from Nel type to Bloch type is about 138?nm, which is much larger than the critical value of traditional Fe- and Co-based soft magnetic films with negligible magnetocrystalline anisotropy. Theoretical calculation was also performed and the calculated result agrees well with experimental data.

  7. Simulation on the Effect of Bottle Wall Thickness Distribution using Blow Moulding Technique

    NASA Astrophysics Data System (ADS)

    Suraya, S.; Azman, M. D.; Fatchurrohman, N.; Jaafar, A. A.; Yusoff, A. R.

    2016-02-01

    The aims of this study are to assess the deformation behavior of a polymeric material during a blow moulding process. Transient computations of two dimensional model of a PP bottle were performed using ANSYS Polyflow computer code to predict the wall thickness distribution at four different parison's diameter; 8mm, 10mm, 18mm, and 20mm. Effects on the final wall thickness diameter and time step are studied. The simulated data shows that the inflation performance degrades with increasing parison diameter. It is concluded that the blow moulding process using 10mm parison successfully meet the product processing requirements. Factors that contribute to the variation in deformation behaviour of the plastic during the manufacturing process are discussed.

  8. A thermoelastic transversely isotropic thick walled cylinder/disk application: An analytical solution and study

    NASA Technical Reports Server (NTRS)

    Arnold, S. M.

    1989-01-01

    A continuum theory is utilized to represent the thermoelastic behavior of a thick walled composite cylinder that can be idealized as transversely isotropic. A multiaxial statement of the constitutive theory employed is presented, as well as the out of the plane of isotropy, plane stress, and plane strain reductions. The derived analytical solution presented is valid for a cylindrical tube or thin disk with a concentric hole, subjected to internal and/or external pressure and a general radial temperature distribution. A specific problem examined is that of a thick walled cylinder subjected to an internal and external pressure loading and a linear radial temperature distribution. The results are expressed in nondimensional form and the effects on the response behavior are examined for various material properties, fiber orientation and types of loadings.

  9. Giant Cutaneous Leiomyosarcoma Originating From the Abdominal Wall: A Case Report

    PubMed Central

    Eken, Huseyin; Karagul, Servet; Topgül, Koray; Yoruker, Savaş; Ozen, Necati; Gun, Seda; Balci, Mecdi Gurhan; Somuncu, Erkan; Cimen, Orhan; Soyturk, Mehmet; Karavas, Erdal

    2016-01-01

    Patient: Male, 44 Final Diagnosis: Cutaneous Leiomyosarcoma Symptoms: Abdominal mass Medication: — Clinical Procedure: Surgery Specialty: Surgery Objective: Rare disease Background: Leiomyosarcoma, a rare type of tumor, accounts for 5–10% of all soft tissue tumors. Case Report: A 44-year-old male patient was admitted to the emergency service of our medical faculty with the complaints of fatigue and abdominal mass. Conclusions: The pathology result was leiomyosarcoma. Leiomyosarcoma of the skin is rare and our case is the largest such lesion reported in the literature. PMID:26787636

  10. Increased wall thickness using ultrasonography is associated with inflammation in an animal model of experimental colitis

    PubMed Central

    Lied, Gülen Arslan; Milde, Anne Marita; Nylund, Kim; Mujic, Maja; Grimstad, Tore; Hausken, Trygve; Gilja, Odd Helge

    2012-01-01

    Experimentally induced colitis is used in animals to investigate pathophysiological mechanisms in inflammatory bowel disease. When following disease course and treatment effects, it should be possible to perform repeated measurements without harming the animals. This pilot study was performed to investigate whether transabdominal ultrasound using a clinical scanner could be used on rats to demonstrate bowel inflammation in an experimental colitis model. Colitis was induced by either 5% dextran sodium sulfate (DSS) in drinking water for 7 days or a single dose of intracolonic trinitrobenzene sulfonic acid (TNBS). Using ultrasonography, wall thickness of distal colon, cecum, and small bowel was recorded prior to and after DSS, and prior to, 2, and 7 days after TNBS. Blood (tumor necrosis factor [TNF]-alpha) and fecal samples (HemoFEC occult blood) were taken from each group on the same days as sonography. Thereafter, rats were killed and specimens for histology were taken. Wall thickness of distal colon, not of cecum or small bowel, increased significantly after 7 days of DSS, and wall thickness of both distal colon and small bowel increased on day 2 and 7 after TNBS. TNF-alpha increased after 7 days in the latter group only. There was a significant correlation between ultrasonographic measurements and combined histology score of distal colon in the DSS group. HemoFEC was also positive in accordance with sonographic and histological features. Increased intestinal wall thickness in response to both DSS- and TNBS-induced colitis was able to be visualized by transabdominal sonography. Moreover, ultrasound findings, occult blood sampling, and histological findings supported each other, indicating that ultrasonography can be used to assess inflammation in a rat experimental model. PMID:23055765

  11. Chest wall thickness measurements of the LLNL phantom for small area germanium detector counting.

    PubMed

    Kramer, G H; Lee, T Y; Chang, S Y

    2000-08-01

    The Lawrence Livermore National Laboratory (LLNL) phantom was developed to calibrate lung counting systems that are used to estimate plutonium and other low energy photon emitting radionuclides deposited in the lung. Originally, low energy photon counting systems consisted of sodium iodide or phoswich detectors, but they have been largely replaced by smaller germanium detector arrays. The average chest wall thicknesses of the LLNL phantom's torso plate and its overlay plates provided by the manufacturer refer to the regions covered by phoswich detectors; however, germanium detectors are of a different size and are placed in different locations on the phantom's torso plate. Previous work has shown that the manufacturer's data were not applicable for large area germanium detectors. The lung counting system at the Korea Atomic Energy Institute (KAERI) is a small area germanium detector array. Although the detectors are placed within the phoswich circles, only about 25% of the area is covered by the detectors. The LLNL phantom at KAERI has been examined to determine if the manufacturer's data are valid or if new chest wall thickness values must be determined. This paper presents chest wall thickness data for the LLNL phantom with and without its B-series overlay plates at 17 keV, 60 keV, 200 keV, and 1,500 keV and shows that these values are different from the manufacturer's values. PMID:10910393

  12. A role of 18F-fluorodeoxyglucose positron emission/computed tomography in a strategy for abdominal wall metastasis of colorectal mucinous adenocarcinoma developed after laparoscopic surgery

    PubMed Central

    2011-01-01

    Metastasis to the abdominal wall including port sites after laparoscopic surgery for colorectal cancer is rare. Resection of metastatic lesions may lead to greater survival benefit if the abdominal wall metastasis is the only manifestation of recurrent disease. A 57-year-old man, who underwent laparoscopic surgery for advanced mucinous adenocarcinoma of the cecum 6 years prior, developed a nodule in the surgical wound at the lower right abdomen. Although tumor markers were within normal limits, the metastasis to the abdominal wall and abdominal cavity from the previous cecal cancer was suspected. An abdominal computed tomography scan did not provide detective evidence of metastasis. 18F-fluorodeoxyglucose positron emission/computed tomography (18F-FDG PET/CT) was therefore performed, which demonstrated increased 18F-fluorodeoxyglucose uptake (maximum standardized uptake value: 3.1) in the small abdominal wall nodule alone. Histopathological examination of the resected nodule confirmed the diagnosis of metastatic mucinous adenocarcinoma. Prognosis of intestinal mucinous adenocarcinoma is reported to be poorer than that of non-mucinous adenocarcinoma. In conclusion, this case suggests an important role of 18F-FDG PET/CT in early diagnosis and decision-making regarding therapy for recurrent disease in cases where a firm diagnosis of recurrent colorectal cancer is difficult to make. PMID:21352607

  13. Abdominopelvic actinomycosis in three different locations with invasion of the abdominal wall and ureteric obstruction: An uncommon presentation

    PubMed Central

    Galata, Christian L.; Vogelmann, Roger; Gaiser, Timo; Post, Stefan; Horisberger, Karoline

    2015-01-01

    Introduction Actinomycosis is a rare chronic infectious disease caused by Gram-positive anaerobic bacteria that normally colonize the bronchial system and gastrointestinal tract in humans. The most common diseases associated with actinomycosis are orocervicofacial, thoracic and abdominal infections involving Actinomyces israelii. Due to its rarity, its various clinical presentations and often-infiltrative characteristics in radiological imaging, it can easily be mistaken for other clinical conditions, including malignancy. Presentation of case We present an uncommon case of extended abdominopelvic actinomycosis with infiltrative lesions in multiple locations, including an abscess in the abdominal wall and ureteric obstruction, which underwent successful surgical and subsequent long-term antibiotic therapy. Discussion To our knowledge, such a combination of different sites of manifestation has not yet been reported for actinomycosis in the presence of an IUD. Possible differential diagnoses included diverticulitis with covered perforation, pelvic inflammatory disease, tuberculosis and inflammatory bowel disease. The possibility of a malignant process required radical resection. As in most cases of actinomycosis, diagnosis could not be established with certainty until postoperative pathology investigation. Conclusion A rare actinomyceal infection should be considered in patients with a non-specific pelvic mass and atypical abdominal presentations, especially if a previous history of IUD usage is known. PMID:26001364

  14. Abdominal wall hernia and aortic injury secondary to blunt trauma: Case report and review of the literature

    PubMed Central

    Ballard, David H.; Kaskas, Nadine M.; Hamidian Jahromi, Alireza; Skweres, Justin; Youssef, Asser M.

    2014-01-01

    INTRODUCTION Traumatic abdominal wall hernia (TAWH) and traumatic abdominal aortic injury (TAAI) are two uncommon complications secondary to blunt trauma. In both TAWH and TAAI, reported cases are often associated with poly-trauma. TAWH may be initially missed if more pressing issues are identified during the patient's primary survey. TAAI may be an incidental finding on imaging or, if severe, a cause of an acute abdomen and hemodynamic abnormality. PRESENTATION OF CASE A 54-year-old white male suffered a TAWH and TAAI (pseudoaneurysm) due to severe blunt trauma. TAWH was apparent on physical exam and the TAAI was suspected on computed tomography (CT). The patient's TAWH was managed with a series of abdominal explorations and the TAAI was repaired with endovascular stenting. DISCUSSION TAWH and TAAI are commonly due to severe blunt trauma from motor vehicle collisions. Diagnosis is made through physical exam, imaging studies, or surgical exploration. A variety of surgical techniques achieve technical success. CONCLUSION The patient with blunt trauma to the abdomen is at risk for TAWH and TAAI, which are often associated with other injuries. Investigations should include thorough clinical exam through secondary survey and radiologic imaging in the hemodynamically normal patient. PMID:25437685

  15. Detection of colonic polyp candidates with level set-based thickness mapping over the colon wall

    NASA Astrophysics Data System (ADS)

    Han, Hao; Li, Lihong; Duan, Chaijie; Zhao, Yang; Wang, Huafeng; Liang, Zhengrong

    2015-03-01

    Further improvement of computer-aided detection (CADe) of colonic polyps is vital to advance computed tomographic colonography (CTC) toward a screening modality, where the detection of flat polyps is especially challenging because limited image features can be extracted from flat polyps, and the traditional geometric features-based CADe methods usually fail to detect such polyps. In this paper, we present a novel pipeline to automatically detect initial polyp candidates (IPCs), especially flat polyps, from CTC images. First, the colon wall mucosa was extracted via a partial volume segmentation approach as a volumetric layer, where the inner border of colon wall can be obtained by shrinking the volumetric layer using level set based adaptive convolution. Then the outer border of colon wall (or the colon wall serosa) was segmented via a combined implementation of geodesic active contour and Mumford-Shah functional in a coarse-to-fine manner. Finally, the wall thickness was estimated along a unique path between the segmented inner and outer borders with consideration of the volumetric layers and was mapped onto a patient-specific three-dimensional (3D) colon wall model. The IPC detection results can usually be better visualized in a 2D image flattened from the 3D model, where abnormalities were detected by Z-score transformation of the thickness values. The proposed IPC detection approach was validated on 11 patients with 22 CTC scans, and each scan has at least one flat poly annotation. The above presented novel pipeline was effective to detect some flat polyps that were missed by our CADe system while keeping false detections in a relative low level. This preliminary study indicates that the presented pipeline can be incorporated into an existing CADe system to enhance the polyp detection power, especially for flat polyps.

  16. Blood Vessel Matrix Seeded with Cells: A Better Alternative for Abdominal Wall Reconstruction—A Long-Term Study

    PubMed Central

    Jundziłł, Arkadiusz; Nazarewski, Łukasz; Kotela, Andrzej; Kloskowski, Tomasz; Skopińska-Wisniewska, Joanna; Łukasiewicz, Aleksander; Nazarewski, Sławomir; Kotela, Ireneusz; Pokrywczyńska, Marta; Marszałek, Andrzej; Drewa, Tomasz

    2015-01-01

    Purpose. The aim of this study was to present abdominal wall reconstruction using a porcine vascular graft seeded with MSC (mesenchymal stem cells) on rat model. Material and Methods. Abdominal wall defect was prepared in 21 Wistar rats. Acellular porcine-vascular grafts taken from aorta and prepared with Triton X were used. 14 aortic grafts were implanted in place, of which 7 grafts were seeded with rat MSC cells (Group I), and 7 were acellular grafts (Group II). As a control, 7 standard polypropylene meshes were used for defect augmentation (Group III). The assessment method was performed by HE and CD31 staining after 6 months. The mechanical properties have been investigated by Zwick&Roell Z0.5. Results. The strongest angiogenesis and lowest inflammatory response were observed in Group I. Average capillaries density was 2.75, 0.75, and 1.53 and inflammatory effect was 0.29, 1.39, and 2.72 for Groups I, II, and III, respectively. The means of mechanical properties were 12.74 ± 1.48, 7.27 ± 1.56, and 14.4 ± 3.7 N/cm in Groups I and II and control, respectively. Conclusions. Cell-seeded grafts have better mechanical properties than acellular grafts but worse than polypropylene mesh. Cells improved mechanical and physiological properties of decellularized natural scaffolds. PMID:25705696

  17. 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

  18. The intricate role of mast cell proteases and the annexin A1-FPR1 system in abdominal wall endometriosis.

    PubMed

    Paula, Rubens; Oliani, Antonio H; Vaz-Oliani, Denise C M; D'Ávila, Solange C G P; Oliani, Sonia M; Gil, Cristiane D

    2015-02-01

    Endometriosis is a continuous and progressive disease with a poorly understood aetiology, pathophysiology and natural history. This study evaluated the histological differences between eutopic and ectopic endometria (abdominal wall endometriosis) and the expression of mast cell proteases (tryptase and chymase), annexin A1 (ANXA1) and formyl peptide receptor 1 (FPR1). Ectopic endometrium from 18 women with abdominal wall endometriosis and eutopic endometrium from 10 women without endometriosis were obtained. The endometrial samples were analysed by histopathology, immunohistochemistry and ultrastructural immunogold labeling to determine mast cell heterogeneity (tryptase and chymase positive cells) and the expression levels of ANXA1 and FPR1. Histopathological analysis of the endometriotic lesions showed a glandular pattern of mixed differentiation and an undifferentiated morphology with a significant influx of inflammatory cells and a change in mast cell heterogeneity, as evidenced by a significant increase in the number of chymase-positive cells and endogenous chymase expression. The undifferentiated glandular pattern of endometriotic lesions was positively associated with a marked increase and co-localization of ANXA1 and FPR1 in the epithelial cells. In conclusion, the co-upregulated expression of mast cell chymase and ANXA1-FPR1 system in ectopic endometrium suggests their involvement in the development of endometriotic lesions. PMID:25201101

  19. [Dynamics of cytokine profile in patients with postoperative hernias the abdominal wall in prosthesis with polytetrafluoroethylene and polyvinylidene fluoride application].

    PubMed

    Ivanov, S V; Ivanov, I S; Mamedov, R A; Katunina, T P; Tsukanov, A V

    2012-07-01

    The results of experimental and clinical studies for the comparative evaluation of implants used in herniology of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) are presented. Experimental investigations conducted on 200 mice, which in the anterior abdominal wall mesh prosthesis implanted. All animals, regardless of the type of implanted prosthesis, deduced from the experiment at 10, 30 th and 60 th day. Histological investigation of the submissions received. The clinical part is based on an analysis of surgical treatment results of postoperative abdominal wall hernia (POGBS) in 121 patients during the period from 2003 to 2011 patients were divided into 2 groups. The control group included 73 patients who were operated during the period 2005-2007, used PTFE graft "Ecoflon", in the main - 48 patients who from 2008 to 2011 the prosthesis was implanted PVDF - "Uniflex" firm "Linteks". In each group, selected patients whom have examined the profile of cytokines. The results of the studies found that both the material cause marked inflammatory reaction with a characteristic stepwise increased levels of proinflammatory and antiinflammatory cytokines, the dynamics of cytokines indicative of a less pronounced local inflammatory reaction to the prosthesis from the PVDF. In the application of the implant "Uniflex" a lower incidence of exudative complications in comparison with that when using the prosthesis "Ecoflon" it is preferable in clinical use. PMID:23033777

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

    PubMed

    Liu, D L; Waag, R C

    1997-02-01

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

  1. Accurate measurement of respiratory airway wall thickness in CT images using a signal restoration technique

    NASA Astrophysics Data System (ADS)

    Park, Sang Joon; Kim, Tae Jung; Kim, Kwang Gi; Lee, Sang Ho; Goo, Jin Mo; Kim, Jong Hyo

    2008-03-01

    Airway wall thickness (AWT) is an important bio-marker for evaluation of pulmonary diseases such as chronic bronchitis, bronchiectasis. While an image-based analysis of the airway tree can provide precise and valuable airway size information, quantitative measurement of AWT in Multidetector-Row Computed Tomography (MDCT) images involves various sources of error and uncertainty. So we have developed an accurate AWT measurement technique for small airways with three-dimensional (3-D) approach. To evaluate performance of these techniques, we used a set of acryl tube phantom was made to mimic small airways to have three different sizes of wall diameter (4.20, 1.79, 1.24 mm) and wall thickness (1.84, 1.22, 0.67 mm). The phantom was imaged with MDCT using standard reconstruction kernel (Sensation 16, Siemens, Erlangen). The pixel size was 0.488 mm × 0.488 mm × 0.75 mm in x, y, and z direction respectively. The images were magnified in 5 times using cubic B-spline interpolation, and line profiles were obtained for each tube. To recover faithful line profile from the blurred images, the line profiles were deconvolved with a point spread kernel of the MDCT which was estimated using the ideal tube profile and image line profile. The inner diameter, outer diameter, and wall thickness of each tube were obtained with full-width-half-maximum (FWHM) method for the line profiles before and after deconvolution processing. Results show that significant improvement was achieved over the conventional FWHM method in the measurement of AWT.

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

    PubMed

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

    2016-02-01

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

  3. Growth and Remodeling in a Thick-Walled Artery Model: Effects of Spatial Variations in Wall Constituents

    PubMed Central

    Alford, Patrick W.; Humphrey, Jay D.; Taber, Larry A.

    2008-01-01

    A mathematical model is presented for growth and remodeling of arteries. The model is a thick-walled tube composed of a constrained mixture of smooth muscle cells, elastin and collagen. Material properties and radial and axial distributions of each constituent are prescribed according to previously published data. The analysis includes stress-dependent growth and contractility of the muscle and turnover of collagen fibers. Simulations were conducted for homeostatic conditions and for the temporal response following sudden hypertension. Numerical pressure-radius relations and opening angles (residual stress) show reasonable agreement with published experimental results. In particular, for realistic material and structural properties, the model predicts measured variations in opening angles along the length of the aorta with reasonable accuracy. These results provide a better understanding of the determinants of residual stress in arteries and could lend insight into the importance of constituent distributions in both natural and tissue-engineered blood vessels. PMID:17786493

  4. Inverse Transient Analysis for Classification of Wall Thickness Variations in Pipelines

    PubMed Central

    Tuck, Jeffrey; Lee, Pedro

    2013-01-01

    Analysis of transient fluid pressure signals has been investigated as an alternative method of fault detection in pipeline systems and has shown promise in both laboratory and field trials. The advantage of the method is that it can potentially provide a fast and cost effective means of locating faults such as leaks, blockages and pipeline wall degradation within a pipeline while the system remains fully operational. The only requirement is that high speed pressure sensors are placed in contact with the fluid. Further development of the method requires detailed numerical models and enhanced understanding of transient flow within a pipeline where variations in pipeline condition and geometry occur. One such variation commonly encountered is the degradation or thinning of pipe walls, which can increase the susceptible of a pipeline to leak development. This paper aims to improve transient-based fault detection methods by investigating how changes in pipe wall thickness will affect the transient behaviour of a system; this is done through the analysis of laboratory experiments. The laboratory experiments are carried out on a stainless steel pipeline of constant outside diameter, into which a pipe section of variable wall thickness is inserted. In order to detect the location and severity of these changes in wall conditions within the laboratory system an inverse transient analysis procedure is employed which considers independent variations in wavespeed and diameter. Inverse transient analyses are carried out using a genetic algorithm optimisation routine to match the response from a one-dimensional method of characteristics transient model to the experimental time domain pressure responses. The accuracy of the detection technique is evaluated and benefits associated with various simplifying assumptions and simulation run times are investigated. It is found that for the case investigated, changes in the wavespeed and nominal diameter of the pipeline are both important to the accuracy of the inverse analysis procedure and can be used to differentiate the observed transient behaviour caused by changes in wall thickness from that caused by other known faults such as leaks. Further application of the method to real pipelines is discussed.

  5. High resolution measurement of translucent plastic wall thicknesses by computerized tomography and neural networks.

    PubMed

    Hemminger, T L; Farrell, R E

    1997-06-01

    Today there is a great deal of interest in the field of plastics design. Several methods can be employed to create plastic products such as injection molding, compression and transfer molding, and blow molding. This paper is concerned with blow molding which is a procedure employed to create hollow plastic containers such as those used to contain liquids and solids in the wholesale and retail markets. An important aspect of blow molding is the measurement of the wall thickness of semi-liquid plastic before the molding procedure has been initiated. Minimization of waste is rapidly becoming a critical consideration within the plastics community due to the cost of raw polymers. Unfortunately, it is also an extremely difficult task to measure the thickness considering the high temperatures and elasticity of the polymers in question. This paper presents initial research on a non-invasive approach for wall thickness measurements of semi-liquid plastics through the utilization of computerized tomography and neural networks. The work described here is based on simulations and on modeling data obtained through experimental means. This technique can be extended to other fields of research as well, such as those related to the development of glass and ceramic products. PMID:9427105

  6. Ultraviolet and infrared studies of the single-walled and multi-walled carbon nanotube films with different thickness

    NASA Astrophysics Data System (ADS)

    Abouelsayed, A.; Eisa, Wael H.; Dawy, M.; Shabaka, A.

    2016-02-01

    Ultraviolet and infrared transmission measurements on an unoriented single-wall (SWCNTs) and multi-wall (MWCNTs) carbon nanotubes films were performed over a frequency range 190-2500 nm for the four different films. A clear change in the fine structure of the infrared spectrum for different films. The higher-energy optical absorption bands, which correspond to transitions across the Van Hove singularities, are not observed in the measured frequency range in the case of MWCNTs films. The broad excitation in the low-energy range below 0.025 eV (Drude peak (EM0)) are attributed to the contributions from metallic carriers localized in a finite length. This Drude peak (EM0) at low-energies is decreased in in case of MWCNTs, which suggests a progressive transition of metallic tubes to insulating state. The unoriented MWCNTs films have an average thickness of about 200-400 nm. The scanning electron microscope pictures of the SWCNTs and the MWCNTs films illustrate the morphological differences between the four studied samples. The volume fraction of the carbon nanotubes in all films appears to be the same, although there is a difference for particles other than nanotubes in the films.

  7. A hybrid method for airway segmentation and automated measurement of bronchial wall thickness on CT.

    PubMed

    Xu, Ziyue; Bagci, Ulas; Foster, Brent; Mansoor, Awais; Udupa, Jayaram K; Mollura, Daniel J

    2015-08-01

    Inflammatory and infectious lung diseases commonly involve bronchial airway structures and morphology, and these abnormalities are often analyzed non-invasively through high resolution computed tomography (CT) scans. Assessing airway wall surfaces and the lumen are of great importance for diagnosing pulmonary diseases. However, obtaining high accuracy from a complete 3-D airway tree structure can be quite challenging. The airway tree structure has spiculated shapes with multiple branches and bifurcation points as opposed to solid single organ or tumor segmentation tasks in other applications, hence, it is complex for manual segmentation as compared with other tasks. For computerized methods, a fundamental challenge in airway tree segmentation is the highly variable intensity levels in the lumen area, which often causes a segmentation method to leak into adjacent lung parenchyma through blurred airway walls or soft boundaries. Moreover, outer wall definition can be difficult due to similar intensities of the airway walls and nearby structures such as vessels. In this paper, we propose a computational framework to accurately quantify airways through (i) a novel hybrid approach for precise segmentation of the lumen, and (ii) two novel methods (a spatially constrained Markov random walk method (pseudo 3-D) and a relative fuzzy connectedness method (3-D)) to estimate the airway wall thickness. We evaluate the performance of our proposed methods in comparison with mostly used algorithms using human chest CT images. Our results demonstrate that, on publicly available data sets and using standard evaluation criteria, the proposed airway segmentation method is accurate and efficient as compared with the state-of-the-art methods, and the airway wall estimation algorithms identified the inner and outer airway surfaces more accurately than the most widely applied methods, namely full width at half maximum and phase congruency. PMID:26026778

  8. Injection-moulded models of major and minor arteries: the variability of model wall thickness owing to casting technique.

    PubMed

    O'Brien, T; Morris, L; O'Donnell, M; Walsh, M; McGloughlin, T

    2005-09-01

    Cardiovascular disease of major and minor arteries is a common cause of death in Western society. The wall mechanics and haemodynamics within the arteries are considered to be important factors in the disease formation process. This paper is concerned with the development of an efficient computer-integrated technique to manufacture idealized and realistic models of diseased major and minor arteries from radiological images and to address the issue of model wall thickness variability. Variations in wall thickness from the original computer models to the final castings are quantified using a CCD camera. The results found that wall thickness variation from the major and minor idealized artery models to design specification were insignificant, up to a maximum of 16 per cent. In realistic models, however, differences were up to 23 per cent in the major arterial models and 58 per cent in the minor arterial models, but the wall thickness variability remained within the limits of previously reported wall thickness results. It is concluded that the described injection moulding procedure yields idealized and realistic castings suitable for use in experimental investigations, with idealized models giving better agreement with design. Wall thickness is variable and should be assessed after the models are manufactured. PMID:16225154

  9. Influence of remaining dentin wall thickness on the fracture strength of endodontically treated tooth

    PubMed Central

    Haralur, Satheesh B.; Al-Qahtani, Ali Saad; Al-Qarni, Marie Mohammed; Al-Homrany, Rami Mohammed; Aboalkhair, Ayyob Ehsan

    2016-01-01

    Background: Remaining dentin wall thickness may influence the fracture resistance of tooth. Aims: To investigate the effect of various coronal dentin wall widths on the fracture strength of root canal treated teeth. Materials and Methods: Fifty recently extracted single canal mandibular premolars were used for the study. Ten unrestored teeth were used as control (Group 1); remaining teeth were root canal treated and divided into four groups (n = 10). The Groups 2a, 2b and 3a, 3b were having 2.5 mm, 1.5 mm remaining dentin with and without post, respectively. The samples fracture resistance was tested under the universal testing machine. The data were analyzed with one-way ANOVA and post-hoc Tukey test for comparative evaluation. Results: The mean fracture strength observed in Group 1 was (29.75 Mpa) followed by Group 2a (28.97 Mpa), Group 2b (27.70 Mpa), Group 3a (23.39 Mpa), and Group 3b (16.38 Mpa). There was no statistically significant difference between control and Groups 2a and 2b with P > 0.05. The post contributed significantly for fracture resistance in Group 3a. Conclusion: The endodontic post is not required in root canal treated teeth >2.5 mm coronal dentin wall width while the post is essential for a tooth with <1.5 mm dentin wall width to improve fracture resistance. PMID:26957796

  10. Numerical study of turbulent natural convection in a cube having finite thickness heat-conducting walls

    NASA Astrophysics Data System (ADS)

    Sheremet, Mikhail A.; Miroshnichenko, Igor V.

    2015-11-01

    Three-dimensional transient natural convection in a cubic enclosure having finite thickness solid walls subject to opposing and horizontal temperature gradient has been investigated by a finite volume method. The turbulent flow considered into the volume is described mathematically by the 3D Reynolds averaged Navier-Stokes equations using the standard k-ɛ model with wall functions, including the energy equation. The velocity and temperature distributions were calculated at fixed Prandtl number, Pr = 0.7 and different values of the Rayleigh number, thermal conductivity ratio and dimensionless time. Three-dimensional velocity and temperature fields, temperature profiles at middle cross-sections and average Nusselt numbers have been presented. It has been found that an insertion of the third coordinate for the conjugate problem leads to a decrease in the average Nusselt number by 5.8 % in conditions of a stationary heat transfer mode.

  11. Failure prediction method for hydro forming simulation of thick walled tubes

    NASA Astrophysics Data System (ADS)

    Kolleck, Ralf; Auer, Peter; Auer, Gerfried

    2011-05-01

    The industrial production of thick walled hydro formed steel parts is a process difficult to control. In particular the prevention of cracks in the production of these parts is very important. It is of utmost importance to have a virtual tool to predict forming results. Standard methods for the simulation of hydro formed parts base upon processes using a shell element formulation and implement a forming limit curve (FLC) for crack prediction. But the forming limit curve is limited to the case of linear strain paths. The initial FLC is no longer valid in the case of nonlinear strain paths. Because of the geometric specifications of the investigated parts—thick walls, compact dimensions, high strains—and the known limitations of the forming limit curve—which don't accord to the hydro forming process— these standard simulation methods are not applicable for the present investigations. A new approach to simulate thick walled hydro formed parts is the use of a volume element formulation in combination with a more complex failure criterion, which gives information about the risk of ductile normal fracture and ductile shear fractures with nonlinear strain paths. The onset of necking must be predicted directly by the volume elements. The aim of this work is to implement the failure criteria in a hydroforming simulation and to compare the results of the simulation with real cracked test parts. The commercial FEM code PamStamp 2G is used as a solver and a comprehensive fracture model is applied. This fracture model distinguishes between two mechanisms responsible for ductile fracture. One is the void growth and coalescence (ductile normal fracture) and the other one is the shear failure model (ductile shear fracture).

  12. Genetic variation in NCAM1 contributes to left ventricular wall thickness in hypertensive families

    PubMed Central

    Arnett, Donna K.; Meyers, Kristin J.; Devereux, Richard B.; Tiwari, Hemant K.; Gu, Charles C.; Vaughan, Laura K.; Perry, Rodney T.; Patki, Amit; Claas, Steven A.; Sun, Yan V.; Broeckel, Ulrich; Kardia, Sharon L.

    2012-01-01

    Rationale Left ventricular (LV) mass and related phenotypes are heritable, important predictors of cardiovascular disease, particularly in hypertensive individuals. Objective Identify genetic predictors of echocardiographic phenotypes in hypertensive families. Methods & Results A multi-stage genome-wide association study (GWAS) was conducted in hypertensive-ascertained African American families (HyperGEN, Stage I; GENOA, Stage II); findings were replicated in HyperGEN Caucasian families (Stage III). Echocardiograms were collected using a common protocol, and participants were genotyped with the Affymetrix Genome-Wide Human SNP 6.0 Array. In Stages I and II, 1258 and 989 African Americans, and Stage III 1316 Caucasians, were analyzed using mixed models adjusted for ancestry. Phenotypes included LV mass, LV internal dimension (LVID), wall thicknesses (posterior (PWT) and intraventricular septum (IVST)), and relative wall thickness (RWT). In Stage I, 5 single nucleotide polymorphisms (SNP) had P≤10−6. In Stage II, one SNP (rs1436109; NCAM1 intron 1) replicated with the same phenotype (PWT, P=0.025) in addition to RWT (P=0.032). In Stage III, rs1436109 was associated with RWT (P=5.47×10−4) and LVID (P=1.86×10−4). Fisher’s combined P-value for all stages was RWT=3.80×10−9, PWT=3.12×10−7, IVST=8.69×10−7, LV mass=2.52×10−3, and LVID=4.80×10−4. Conclusions This GWAS conducted in hypertensive families identified a variant in NCAM1 associated with LV wall thickness and RWT. NCAM is upregulated during the remodeling period of hypertrophy to heart failure in Dahl salt-sensitive rats. Our initial screening in hypertensive African-Americans may have provided the context for this novel locus. PMID:21212386

  13. The Carter-Thomason Needle Suture Passer to Correct Cannula-Induced Defects and Vascular Injuries in the Abdominal Wall During Laparoscopy

    PubMed

    Ortega

    1996-08-01

    Postoperative omental and bowel entrapment secondary to incisional hernias and life-threatening hemorrhage secondary to anterior abdominal wall bleeding may occur during cannula placement. The Carter-Thomason needle suture passer was used to correct 20 fascial and peritoneal cannula defects and 7 severe anterior abdominal wall bleeders. The procedure was performed quickly and successfully in all instances. The instrument provides a safe, rapid, easy, and cost-effective way to correct complications secondary to the creation of surgical ports during laparoscopic surgery. PMID:9074205

  14. Assessment of the abdominal wall function after pedicled TRAM flap surgery for breast reconstruction: Use of modified mesh repair for the donor defect

    PubMed Central

    Cyriac, Chacko; Sharma, Ramesh Kumar; Singh, Gurpreet

    2010-01-01

    Background: The pedicled TRAM flap has been a workhorse of autologous breast reconstruction for decades. However, there has been a rising concern about the abdominal wall donor site morbidity with the use of conventional TRAM flap. This has generally been cited as one of the main reasons for resorting to “abdominal wall friendly” techniques. This study has been undertaken to assess the abdominal wall function in patients with pedicled TRAM flap breast reconstruction. The entire width of the muscle and the overlying wide disk of anterior rectus sheath were harvested with the TRAM flap in all our patients and the anterior rectus sheath defect was repaired by a Proline mesh. Materials and Methods: Abdominal wall function was studied in 21 patients who underwent simultaneous primary unipedicled TRAM flap reconstruction after mastectomy for cancer. In all the patients, the abdominal wall defect was repaired using wide sheet of Proline mesh both as inlay and onlay. The assessment tools included straight and rotational curl ups and a subjective questionnaire. The abdominal wall was also examined for any asymmetry, bulge, or hernia. The minimal follow-up was 6 months postoperative. The objective results were compared with normal unoperated volunteers. Results and Conclusions: The harvesting the TRAM flap certainly results in changes to the anterior abdominal wall that can express themselves to a variable degree. A relatively high incidence of asymptomatic asymmetry of the abdomen was seen. There was total absence of hernia in our series even after a mean follow-up period of 15.5 months. A few patients were only able to partially initiate the sit up movement and suffered an important loss of strength. In most patients, synergists took over the functional movement but as the load increased, flexion and rotation performances decreased. The lack of correlation between exercise tests and the results of the questionnaire suggests that this statistically significant impairment was functionally not important. The patients encountered little or no difficulty in theis day-to-day activities. Our modification of use of a wide mesh as inlay and onlay repair minimizes the donor site morbidity. This also avoids maneuvers meant for primary closure of the rectus sheath defects, which can result in distortion of umbilicus. Therefore, in conclusion, the unipedicled TRAM flap should be regarded as a valuable option in breast reconstruction provided careful repair of the abdominal wall defect is undertaken using Proline mesh. PMID:21217974

  15. IFE thick liquid wall chamber dynamics: Governing mechanisms andmodeling and experimental capabilities

    SciTech Connect

    Raffray, A.R.; Meier, W.; Abdel-Khalik, S.; Bonazza, R.; Calderoni, P.; Debonnel, C.S.; Dragojlovic, Z.; El-Guebaly, L.; Haynes,D.; Latkowski, J.; Olson, C.; Peterson, P.F.; Reyes, S.; Sharpe, P.; Tillack, M.S.; Zaghloul, M.

    2005-01-24

    For thick liquid wall concepts, it is important to understand the different mechanisms affecting the chamber dynamics and the state of the chamber prior to each shot a compared with requirements from the driver and target. These include ablation mechanisms, vapor transport and control, possible aerosol formation, as well as protective jet behavior. This paper was motivated by a town meeting on this subject which helped identify the major issues, assess the latest results, review the capabilities of existing modeling and experimental facilities with respect to addressing remaining issues, and helping guide future analysis and R&D efforts; the paper covers these exact points.

  16. Effect of pipe wall thickness on the heat fusion quality of polyethylene saddle joints. Task report, January-July 1992

    SciTech Connect

    Pimputkar, S.M.; Stets, J.A.

    1995-07-01

    Identical saddle fittings are used on polyethylene gas distribution pipe of the same diameter but different wall thickness. The objective of this study was to determine the effect of pipe wall thickness on saddle fusion integrity. Several saddle joints were made at the manufacturers` recommended conditions, while only the wall thickness was varied. When making most of the joints, thermocouples were used to determine the temperatures at 10 saddle and pipe locations during heating. The saddle joints were also cut into test specimens and subjected to shear impact testing in order to determine the strength of the joints. There was no measurable effect of pipe wall thickness on saddle fusion quality (defined by the average shear impact energy of each joint).

  17. Effect of bladder wall thickness on miniature pneumatic artificial muscle performance.

    PubMed

    Pillsbury, Thomas E; Kothera, Curt S; Wereley, Norman M

    2015-10-01

    Pneumatic artificial muscles (PAMs) are actuators known for their high power to weight ratio, natural compliance and light weight. Due to these advantages, PAMs have been used for orthotic devices and robotic limbs. Small scale PAMs have the same advantages, as well as requiring greatly reduced volumes with potential application to prostheses and small scale robotics. The bladder of a PAM affects common actuator performance metrics, specifically: blocked force, free contraction, hysteresis, and dead-band pressure. This paper investigates the effect that bladder thickness has on static actuation performance of small scale PAMs. Miniature PAMs were fabricated with a range of bladder thicknesses to quantify the change in common actuator performance metrics specifically: blocked force, free contraction, and dead-band pressure. These PAMs were then experimentally characterized in quasi-static conditions, where results showed that increasing bladder wall thickness decreases blocked force and free contraction, while dead-band pressure increases. A nonlinear model was then applied to determine the structure of the stress-strain relationship that enables accurate modeling and the minimum number of terms. Two nonlinear models are compared and the identified parameters are analyzed to study the effect of the bladder thickness on the model. PMID:26414160

  18. Comparison of polypropylene and polyethylene terephthalate (Dacron) meshes for abdominal wall hernia repair: a chemical and morphological study.

    PubMed

    Bracco, P; Brunella, V; Trossarelli, L; Coda, A; Botto-Micca, F

    2005-03-01

    For the first time, by scanning electron microscopy (SEM), polypropylene (PP) excised meshes (ethylene oxide sterilized) for abdominal wall hernia repair have been shown to be greatly damaged physically, independently of the implantation time, while the polyethylene terephthalate (PET), or Dacron, ones (gamma radiation sterilized), did not undergo alterations due to the sterilization process and were not damaged, even after long implantation periods. Fourier-Transform Infrared Spectroscopy (FTIR) study of PP and PET excised meshes, as well as of their extracts with cyclohexane, has shown the presence of species, such as squalene, palmitic and stearic acid, in some cases, cholesterol, transferred from the surrounding tissues to the polymer during the implantation period. In the case of PP meshes, these small organic molecules would reduce physical and mechanical properties of the material. A hypothesis is presented to account for the better behavior (not in the clinical sense) of PET meshes. PMID:15365886

  19. 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

  20. 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

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

    PubMed

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

    2015-08-01

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

  2. On what controls the spacing of spontaneous adiabatic shear bands in collapsing thick-walled cylinders

    NASA Astrophysics Data System (ADS)

    Lovinger, Zev; Rosenberg, Zvi; Rittel, Daniel

    2015-09-01

    Shear bands formation in collapsing thick walled cylinders occurs in a spontaneous manner. The advantage of examining spontaneous, as opposed to forced shear localization, is that it highlights the inherent susceptibility of the material to adiabatic shear banding without prescribed geometrical constraints. The Thick-Walled Cylinder technique (TWC) provides a controllable and repeatable technique to create and study multiple adiabatic shear bands. The technique, reported in the literature uses an explosive cylinder to create the driving force, collapsing the cylindrical sample. Recently, we developed an electro-magnetic set-up using a pulsed current generator to provide the collapsing force, replacing the use of explosives. Using this platform we examined the shear band evolution at different stages of formation in 7 metallic alloys, spanning a wide range of strength and failure properties. We examined the number of shear bands and spacing between them for the different materials to try and figure out what controls these parameters. The examination of the different materials enabled us to better comprehend the mechanisms which control the spatial distribution of multiple shear bands in this geometry. The results of these tests are discussed and compared to explosively driven collapsing TWC results in the literature and to existing analytical models for spontaneous adiabatic shear localization.

  3. Bi-stable characteristics of thick-walled domes with applications to soft material snapping

    NASA Astrophysics Data System (ADS)

    Madhukar, Amit

    2015-03-01

    Bi-stable structures can exhibit interesting mechanical properties which makes them the focus of research in the field of extreme mechanics. Fast transitions can occur between equilibrium states with very little actuation force. One such bi-stable structure is the thick-walled dome. In this work, we apply finite element techniques to examine the stability of such spherical, thick-walled domes undergoing large deformation. We apply the following methods to two structures: a single-layered system as well as bi-layered colloidal microparticles which actuate through pH driven mismatched swelling. The presence of a metastable state is identified by the energy characteristics alone. Monotonically increasing energy represents a mono-stable structure. Bi-stability occurs when we achieve a local energy minimum at some non-zero displacement. Of more interest is the region near the transition of these states where we find a so called pseudo-bi-stable state where small perturbations results in fast transition from the elevated energy state, or snapping. We use our simulations to map out the critical geometric parameters that govern this behavior in order to design a dome to snap. Experimental results are used to validate the simulation results.

  4. Electromagnetic acoustic transducers for wall thickness applications in the petrochemical industry

    NASA Astrophysics Data System (ADS)

    Edwards, C.; Dixon, S.; Widdowson, A.; Palmer, S. B.

    2000-05-01

    Electromagnetic acoustic transducers (EMATs) are now becoming widely used in the field, for example for boiler tube wall thickness surveys in Power Generation plant. In general EMATs work efficiently on steel components with a surface oxide layer, where the oxides can be residual mill scale from the steel manufacturing process due to in-service growth in boilers or chemical processing plant. Very often these oxides have rough surfaces and have to be removed prior to conventional ultrasonic inspection. This can be both time consuming and costly, in addition the removal of the protective oxide layer accelerates the future wall lose rate of the pipe or vessel. As well as the Power Generation application, EMATs can also be used for ultrasonic inspection of petrochemical tubulars without having to remove oxides giving the same associated benefits. This paper presents results obtained from laboratory trials of EMAT thickness monitoring of petrochemical plant pipe samples and real EMAT surveys carried out on-site on refinery plant. In parallel with the practical application of EMATs we are studying the underlying physics of operation with the aim of predicting the EMAT performance for steels with and without oxide layers.

  5. Suitability of Pharmacokinetic Models for Dynamic Contrast-Enhanced MRI of Abdominal Aortic Aneurysm Vessel Wall: A Comparison

    PubMed Central

    Nguyen, V. Lai; Kooi, M. Eline; Backes, Walter H.; van Hoof, Raf H. M.; Saris, Anne E. C. M.; Wishaupt, Mirthe C. J.; Hellenthal, Femke A. M. V. I.; van der Geest, Rob J.; Kessels, Alfons G. H.; Schurink, Geert Willem H.; Leiner, Tim

    2013-01-01

    Purpose Increased microvascularization of the abdominal aortic aneurysm (AAA) vessel wall has been related to AAA progression and rupture. The aim of this study was to compare the suitability of three pharmacokinetic models to describe AAA vessel wall enhancement using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Materials and Methods Patients with AAA underwent DCE-MRI at 1.5 Tesla. The volume transfer constant (Ktrans), which reflects microvascular flow, permeability and surface area, was calculated by fitting the blood and aneurysm vessel wall gadolinium concentration curves. The relative fit errors, parameter uncertainties and parameter reproducibilities for the Patlak, Tofts and Extended Tofts model were compared to find the most suitable model. Scan-rescan reproducibility was assessed using the interclass correlation coefficient and coefficient of variation (CV). Further, the relationship between Ktrans and AAA size was investigated. Results DCE-MRI examinations from thirty-nine patients (mean age±SD: 72±6 years; M/F: 35/4) with an mean AAA maximal diameter of 49±6 mm could be included for pharmacokinetic analysis. Relative fit uncertainties for Ktrans based on the Patlak model (17%) were significantly lower compared to the Tofts (37%) and Extended Tofts model (42%) (p<0.001). Ktrans scan-rescan reproducibility for the Patlak model (ICC = 0.61 and CV = 22%) was comparable with the Tofts (ICC = 0.61, CV = 23%) and Extended Tofts model (ICC = 0.76, CV = 22%). Ktrans was positively correlated with maximal AAA diameter (Spearman’s ρ = 0.38, p = 0.02) using the Patlak model. Conclusion Using the presented imaging protocol, the Patlak model is most suited to describe DCE-MRI data of the AAA vessel wall with good Ktrans scan-rescan reproducibility. PMID:24098370

  6. Optimization of Cone Wall Thickness to Reduce High Energy Electron Generation for Fast-Ignition Scheme

    NASA Astrophysics Data System (ADS)

    Kojima, Sadaoki; Zhe, Zhang; Sawada, Hiroshi; Firex Team

    2015-11-01

    In Fast Ignition Inertial Confinement Fusion, optimization of relativistic electron beam (REB) accelerated by a high-intensity laser pulse is critical for the efficient core heating. The high-energy tail of the electron spectrum is generated by the laser interaction with a long-scale-length plasma and does not efficiently couple to a fuel core. In the cone-in-shell scheme, long-scale-length plasmas can be produced inside the cone by the pedestal of a high-intensity laser, radiation heating of the inner cone wall and shock wave from an implosion core. We have investigated a relation between the presence of pre-plasma inside the cone and the REB energy distribution using the Gekko XII and 2kJ-PW LFEX laser at the Institute of Laser Engineering. The condition of an inner cone wall was monitored using VISAR and SOP systems on a cone-in-shell implosion. The generation of the REB was measured with an electron energy analyzer and a hard x-ray spectrometer on a separate shot by injecting the LFEX laser in an imploded target. The result shows the strong correlation between the preheat and high-energy tail generation. Optimization of cone-wall thickness for the fast-ignition will be discussed. This work is supported by NIFS, MEXT/JSPS KAKENHI Grant and JSPS Fellows (Grant Number 14J06592).

  7. An approach for patient-specific multi-domain vascular mesh generation featuring spatially varying wall thickness modeling.

    PubMed

    Raut, Samarth S; Liu, Peng; Finol, Ender A

    2015-07-16

    In this work, we present a computationally efficient image-derived volume mesh generation approach for vasculatures that implements spatially varying patient-specific wall thickness with a novel inward extrusion of the wall surface mesh. Multi-domain vascular meshes with arbitrary numbers, locations, and patterns of both iliac bifurcations and thrombi can be obtained without the need to specify features or landmark points as input. In addition, the mesh output is coordinate-frame independent and independent of the image grid resolution with high dimensional accuracy and mesh quality, devoid of errors typically found in off-the-shelf image-based model generation workflows. The absence of deformable template models or Cartesian grid-based methods enables the present approach to be sufficiently robust to handle aneurysmatic geometries with highly irregular shapes, arterial branches nearly parallel to the image plane, and variable wall thickness. The assessment of the methodology was based on i) estimation of the surface reconstruction accuracy, ii) validation of the output mesh using an aneurysm phantom, and iii) benchmarking the volume mesh quality against other frameworks. For the phantom image dataset (pixel size 0.105 mm; slice spacing 0.7 mm; and mean wall thickness 1.401±0.120 mm), the average wall thickness in the mesh was 1.459±0.123 mm. The absolute error in average wall thickness was 0.060±0.036 mm, or about 8.6% of the largest image grid spacing (0.7 mm) and 4.36% of the actual mean wall thickness. Mesh quality metrics and the ability to reproduce regional variations of wall thickness were found superior to similar alternative frameworks. PMID:25976018

  8. Airway wall thickness is increased in COPD patients with bronchodilator responsiveness

    PubMed Central

    2014-01-01

    Rationale Bronchodilator responsiveness (BDR) is a common but variable phenomenon in COPD. The CT characteristics of airway dimensions that differentiate COPD subjects with BDR from those without BDR have not been well described. We aimed to assess airway dimensions in COPD subjects with and without BDR. Methods We analyzed subjects with GOLD 1–4 disease in the COPDGene® study who had CT airway analysis. We divided patients into two groups: BDR + (post bronchodilator ΔFEV1 ≥ 10%) and BDR-(post bronchodilator ΔFEV1 < 10%). The mean wall area percent (WA%) of six segmental bronchi in each subject was quantified using VIDA. Using 3D SLICER, airway wall thickness was also expressed as the square root wall area of an airway of 10 mm (Pi10) and 15 mm (Pi15) diameter. %Emphysema and %gas trapping were also calculated. Results 2355 subjects in the BDR-group and 1306 in the BDR + group formed our analysis. The BDR + group had a greater Pi10, Pi15, and mean segmental WA% compared to the BDR-group. In multivariate logistic regression using gender, race, current smoking, history of asthma, %emphysema, %gas trapping, %predicted FEV1, and %predicted FVC, airway wall measures remained independent predictors of BDR. Using a threshold change in FEV1 ≥ 15% and FEV1 ≥ 12% and 200 mL to divide patients into groups, the results were similar. Conclusion BDR in COPD is independently associated with CT evidence of airway pathology. This study provides us with greater evidence of changes in lung structure that correlate with physiologic manifestations of airflow obstruction in COPD. PMID:25248436

  9. Changes in the wall shear stresses (WSS) during the enlargement of Abdominal Aortic Aneurysms (AAA)

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Sparks, Steven R.; Chomaz, Jean-Marc; Lasheras, Juan C.

    2004-11-01

    The changes in the evolution of the spatial and temporal distribution of the WSS and gradients of WSS at different stages of the enlargement of AAAs are important to understand the etiology and progression of this vascular disease, since they affect the wall structural integrity, primarily via the changes induced on the shape, functions and metabolism of the endothelial cells. PIV measurements were performed in aneurysm models, while changing systematically their geometric parameters. We show that, even at very early stages of the disease (dilatation > 30%), the flow separates from the wall and the formation of a large vortex ring followed by internal shear layers leads to the generation of WSS that drastically differ from the healthy vessel. Inside the AAA, the mean WSS decreases to zero and the magnitude of the WSS can be as low as 26% of the value in a healthy vessel. Two regions with distinct patterns of WSS were identified. The region of flow detachment, with oscillatory WSS of very low mean, and the region of flow reattachment, located distally, where large, negative WSS and sustained gradients of WSS are produced as a result of the impact of the vortex ring on the wall.

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

    PubMed Central

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

    2013-01-01

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

  11. A method of computing the transient temperature of thick walls from arbitrary variation of adiabatic-wall temperature and heat-transfer coefficient

    NASA Technical Reports Server (NTRS)

    Hill, P R

    1958-01-01

    A method of calculating the temperature of thick walls has been developed in which the time series and the response to a unit triangle variation of surface temperature concepts are used, together with essentially standard formulas for transient temperature and heat flow into thick walls. The method can be used without knowledge of the mathematical tools of its development. The method is particularly suitable for determining the wall temperature in one-dimensional thermal problems in aeronautics where there is a continuous variation of the heat-transfer coefficient and adiabatic-wall temperature. The method also offers a convenient means for solving the inverse problem of determining the heat-flow history when temperature history is known.

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

    PubMed

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

    2010-01-01

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

  13. Residual stress analysis in forming process of filament wound thick-walled CFRP pipes

    SciTech Connect

    Kondo, Toshimi; Sekine, Hideki; Nakano, Kunio

    1995-11-01

    Residual stress analysis for the cracking phenomenon of filament would thick-walled CFRP pipes, which frequently occurs in the forming process of curing and thermal cycling through the course of the wet filament winding, was made from both the experimental and theoretical points of view. A simple analytical model to study the cracking in the CFRP pipes was proposed. The pipes are multilayered and reinforced in the axial and circumferential directions alternatively by carbon fibers. Taking account of the anisotropy of mechanical and thermal properties including the shrinkage strain, which depend considerably on the temperature, the residual stresses in the CFRP pipes were elucidated in the forming process, particularly, in cooling of the cure process.

  14. Facilitating protein crystal cryoprotection in thick-walled plastic capillaries by high-pressure cryocooling

    PubMed Central

    Chen, Yi-Fan; Tate, Mark W.; Gruner, Sol M.

    2009-01-01

    Many steps in the X-ray crystallographic solution of protein structures have been automated. However, the harvesting and cryocooling of crystals still rely primarily on manual handling, frequently with consequent mechanical damage. An attractive alternative is to grow crystals directly inside robust plastic capillaries that may be cryocooled and mounted on the beamline goniometer. In this case, it is still desirable to devise a way to cryoprotect the crystals, which is difficult owing to the poor thermal conductivity of thick plastic capillary walls and the large thermal mass of the capillary and internal mother liquor. A method is described to circumvent these difficulties. It is shown that high-pressure cryocooling substantially reduced the minimal concentrations of cryoprotectants required to cryocool water inside capillaries without formation of ice crystals. The minimal concentrations of PEG 200, PEG 400 and glycerol necessary for complete vitrification under pressure cryocooling were determined. PMID:19529790

  15. Facilitating protein crystal cryoprotection in thick-walled plastic capillaries by high-pressure cryocooling.

    PubMed

    Chen, Yi-Fan; Tate, Mark W; Gruner, Sol M

    2009-06-01

    Many steps in the X-ray crystallographic solution of protein structures have been automated. However, the harvesting and cryocooling of crystals still rely primarily on manual handling, frequently with consequent mechanical damage. An attractive alternative is to grow crystals directly inside robust plastic capillaries that may be cryocooled and mounted on the beamline goniometer. In this case, it is still desirable to devise a way to cryoprotect the crystals, which is difficult owing to the poor thermal conductivity of thick plastic capillary walls and the large thermal mass of the capillary and internal mother liquor. A method is described to circumvent these difficulties. It is shown that high-pressure cryocooling substantially reduced the minimal concentrations of cryoprotectants required to cryocool water inside capillaries without formation of ice crystals. The minimal concentrations of PEG 200, PEG 400 and glycerol necessary for complete vitrification under pressure cryocooling were determined. PMID:19529790

  16. Validation of semiautomated and locally resolved aortic wall thickness measurements from computed tomography

    PubMed Central

    Shang, Eric K.; Lai, Eric; Pouch, Alison M.; Hinmon, Robin; Gorman, Robert C.; Gorman, Joseph H.; Sehgal, Chandra M.; Ferrari, Giovanni; Bavaria, Joseph E.; Jackson, Benjamin M.

    2014-01-01

    Objective Aortic wall thickness (AWT) is important for anatomic description and biomechanical modeling of aneurysmal disease. However, no validated, noninvasive method for measuring AWT exists. We hypothesized that semiautomated image segmentation algorithms applied to computed tomography angiography (CTA) can accurately measure AWT. Methods Aortic samples from 10 patients undergoing open thoracoabdominal aneurysm repair were taken from sites of the proximal or distal anastomosis, or both, yielding 13 samples. Aortic specimens were fixed in formalin, embedded in paraffin, and sectioned. After staining with hematoxylin and eosin and Masson’s trichrome, sections were digitally scanned and measured. Patients’ preoperative CTA Digital Imaging and Communications in Medicine (DICOM; National Electrical Manufacturers Association, Rosslyn, Va) images were segmented into luminal, inner arterial, and outer arterial surfaces with custom algorithms using active contours, isoline contour detection, and texture analysis. AWT values derived from image data were compared with measurements of corresponding pathologic specimens. Results AWT determined by CTA averaged 2.33 ± 0.66 mm (range, 1.52–3.55 mm), and the AWT of pathologic specimens averaged 2.36 ± 0.75 mm (range, 1.51–4.16 mm). The percentage difference between pathologic specimens and CTA-determined AWT was 9.5% ± 4.1% (range, 1.8%–16.7%). The correlation between image-based measurements and pathologic measurements was high (R = 0.935). The 95% limits of agreement computed by Bland-Altman analysis fell within the range of −0.42 and 0.42 mm. Conclusions Semiautomated analysis of CTA images can be used to accurately measure regional and patient-specific AWT, as validated using pathologic ex vivo human aortic specimens. Descriptions and reconstructions of aortic aneurysms that incorporate locally resolved wall thickness are feasible and may improve future attempts at biomechanical analyses. PMID:24388698

  17. Left Ventricular Relative Wall Thickness Versus Left Ventricular Mass Index in Non-Cardioembolic Stroke Patients

    PubMed Central

    Hashem, M-Sherif; Kalashyan, Hayrapet; Choy, Jonathan; Chiew, Soon K.; Shawki, Abdel-Hakim; Dawood, Ahmed H.; Becher, Harald

    2015-01-01

    Abstract In non-cardioembolic stroke patients, the cardiac manifestations of high blood pressure are of particular interest. Emerging data suggest that echocardiographically determined left ventricular hypertrophy is independently associated with risk of ischemic stroke. The primary objective of this study was to evaluate the frequency of different patterns of left ventricular (LV) remodeling and hypertrophy in a group of consecutive patients admitted with non-cardioembolic stroke or transient ischemic attack (TIA). In particular, we were interested in how often the relative wall thickness (RWT) was abnormal in patients with normal LV mass index (LVMI). As both abnormal RWT and LVMI indicate altered LV remodeling, the secondary objective of this research was to study whether a significant number of patients would be missing the diagnosis of LV remodeling if the RWT is not measured. All patients were referred within 48 hours after a stroke or a TIA for a clinically indicated transthoracic echocardiogram. The echocardiographic findings of consecutive patients with non-cardioembolic stroke or TIA were analyzed. All necessary measurements were performed in 368 patients, who were enrolled in the study. Mean age was 63.7 ± 12.5 years, 64.4% men. Concentric remodeling carried the highest frequency, 49.2%, followed by concentric hypertrophy, 30.7%, normal pattern, 15.5%, and eccentric hypertrophy, 4.1%. The frequency of abnormal left ventricular RWT (80.4%) was significantly higher than that of abnormal LVMI (35.3%), (McNemar P < 0.05). In this group of non-cardioembolic stroke patients, abnormal LV remodeling as assessed by relative wall thickness is very frequent. As RWT was often found without increased LV mass, the abnormal left ventricular geometry may be missed if RWT is not measured or reported. PMID:25997067

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

    PubMed Central

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

    2016-01-01

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

  19. A more realistic thermal shock analysis of a radially multicracked thick-walled cylinder

    NASA Astrophysics Data System (ADS)

    Perl, M.; Ashkenazi, A.

    1992-07-01

    Presently available analyses of multicracking of thick-walled cylinders due to an internal thermal shock, model the shock by a temperature step-change at the cylinder bore, yielding a considerably overestimated temperature field through the cylinder's wall. In the present work a more realistic thermal shock model is employed assuming convection boundary conditions at both the inner and the outer cylinder surfaces. Transient mode I stress intensity factors (SIF), resulting from the thermal shock during the firing process in a typical gun barrel, are evaluated for large arrays of radial cracks emanating from the bore surface of the cylinder. The transient thermal analysis as well as the computation of the SIFs is performed via the finite element method. Once the thermal problem is solved, SIFs at various time steps are calculated for numerous crack arrays (2-1024) and for a wide range of relevant crack lengths. The present analysis emphasizes the importance of using the proper thermal shock model by showing that the previously available results are nonconservative, and exemplifies the favorable effect of the above thermal shock on the effective SIF prevailing at the tips of these cracks.

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

    PubMed

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

    2015-12-01

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

  1. Time-dependent creep stress redistribution analysis of thick-walled functionally graded spheres

    NASA Astrophysics Data System (ADS)

    Loghman, A.; Ghorbanpour Arani, A.; Aleayoub, S. M. A.

    2011-11-01

    Time-dependent creep stress redistribution analysis of thick-walled spheres made of functionally graded material (FGM) subjected to an internal pressure and a uniform temperature field is performed using the method of successive elastic solution. The material creep and mechanical properties through the radial graded direction are assumed to obey a simple power-law variation. Total strains are assumed to be the sum of elastic, thermal and creep strains. Creep strains are time, temperature and stress dependent. Using the equations of equilibrium, compatibility and stress-strain relations a differential equation, containing creep strains, for radial stress are obtained. Ignoring creep strains, a closed-form solution for initial thermoelastic stresses at zero time is presented. It has been found that the material in-homogeneity parameter β has a substantial effect on thermoelastic stresses. From thermoelastic analysis the material identified by β=2 in which a more uniform shear stress distribution occurs throughout the thickness of the FGM sphere is selected for time-dependent stress redistribution analysis. Using the Prandtl-Reuss relations and Norton's creep constitutive model, history of stresses and strains are obtained. It has been found that radial stress redistributions are not significant, however, major redistributions occur for circumferential and effective stresses. It has also been concluded that stresses and strains are changing with time at a decreasing rate so that there is a saturation condition beyond which not much change occurs. Indeed after 50 years the solution approaches the steady-state condition.

  2. Lateral abdominal muscle size at rest and during abdominal drawing-in manoeuvre in healthy adolescents.

    PubMed

    Linek, Pawel; Saulicz, Edward; Wolny, Tomasz; Myśliwiec, Andrzej; Kokosz, Mirosław

    2015-02-01

    Lateral abdominal wall muscles in children and adolescents have not been characterised to date. In the present report, we examined the reliability of the ultrasound measurement and thickness of the oblique external muscle (OE), oblique internal muscle (OI) and transverse abdominal muscle (TrA) at rest and during abdominal drawing-in manoeuvre (ADIM) on both sides of the body in healthy adolescents. We also determined possible differences between boys and girls and defined any factors-such as body mass, height and BMI-that may affect the thickness of the abdominal muscles. B-mode ultrasound was used to assess OE, OI and TrA on both sides of the body in the supine position. Ultrasound measurements at rest and during ADIM were reliable in this age group (ICC3,3 > 0.92). OI was always the thickest and TrA the thinnest muscle on both sides of the body. In this group, an identical pattern of the contribution of the individual muscles to the structure of the lateral abdominal wall (OI > OE > TrA) was observed. At rest and during ADIM, no statistically significant side-to-side differences were demonstrated in either gender. The body mass constitutes between 30% and <50% of the thickness differences in all muscles under examination at rest and during ADIM. The structure of lateral abdominal wall in adolescents is similar to that of adults. During ADIM, the abdominal muscles in adolescents react similarly to those in adults. This study provided extensive information regarding the structure of the lateral abdominal wall in healthy adolescents. PMID:25088309

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

    PubMed Central

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

    2016-01-01

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

  4. Reconstruction of large-size abdominal wall defect using biodegradable poly-p-dioxanone mesh: an experimental canine study

    PubMed Central

    2014-01-01

    Background Reconstruction of large-size abdominal wall defect (AWDs) is a huge challenge faced in current surgical practice. In this study, we aimed to evaluate the effectiveness and safety of biodegradable poly-p-dioxanone (PDO) mesh for reconstructing large-size AWDs in an experimental canine model. Methods Eighteen experimental canines were randomly and equally divided into three groups, namely, a PDO group, a Marlex group and a control group (n = 6 each). Following the creation of a 6 cm 5.5 cm AWD, PDO mesh and Marlex mesh were used to reconstruct the defect in the PDO and Marlex groups, respectively. The defect was closed using relaxation sutures alone in the control group. Animals were killed 24 weeks after surgery, and reconstruction outcomes were evaluated using radiography, histology and biomechanical testing. Results All animals except those in the control group survived the experiment. The PDO group showed no wound dehiscence, herniation or infection, whereas the animals in the Marlex group exhibited marked foreign body reactions. The PDO group had less intraabdominal adhesion than the Marlex group. As shown by radiography, histology and biomechanical testing, PDO mesh exhibited complete degradation and favorable biochemical strength at 24 weeks postsurgery. Conclusions PDO mesh implantation is an effective, safe treatment modality for reconstructing large-size AWDs. PMID:24625138

  5. Abdominal actinomycosis mimicking acute appendicitis.

    PubMed

    Conrad, Robert Joseph; Riela, Steven; Patel, Ravi; Misra, Subhasis

    2015-01-01

    A 52-year-old Hispanic woman presented to the emergency department, reporting worsening sharp lower right quadrant abdominal pain for 3 days. CT of the abdomen and pelvis showed evidence of inflammation in the peritoneal soft tissues adjacent to an enlarged and thick-walled appendix, an appendicolith, no abscess formation and a slightly thickened caecum consistent with acute appendicitis. During laparoscopic appendectomy, the caecum was noted to be firm, raising suspicion of malignancy. Surgical oncology team was consulted and open laparotomy with right hemicolectomy was performed. Pathology reported that the ileocaecal mass was not a malignancy but was, rather, actinomycosis. The patient was discharged after 10 days of intravenous antibiotics in the hospital, with the diagnosis of abdominal actinomycosis. Although the original clinical and radiological findings in this case were highly suggestive of acute appendicitis, abdominal actinomycosis should be in the differential for right lower quadrant pain as it may be treated non-operatively. PMID:26611488

  6. Reconstruction of full-thickness chest wall defects using rectus abdominis musculocutaneous flap: A report of fifteen cases

    SciTech Connect

    Miyamoto, Y.; Hattori, T.; Niimoto, M.; Toge, T. )

    1986-02-01

    In 15 patients chest walls were excised because of recurrent breast cancer, radiation ulcer, or rib tumor. In most cases the full-thickness defect of the chest wall was about 10 x 10 cm. Reconstruction was performed using only a rectus abdominis musculocutaneous flap. No patient developed circulation problems in the flap or severe flail chest, and we had successful results in all our cases. These results show that the rectus abdominis musculocutaneous flap is quite effective and safe to use in the reconstruction of chest wall defects.

  7. Herpes zoster-induced trunk muscle paresis presenting with abdominal wall pseudohernia, scoliosis, and gait disturbance and its rehabilitation: a case report.

    PubMed

    Tashiro, Syoichi; Akaboshi, Kazuto; Kobayashi, Yukiko; Mori, Toshiki; Nagata, Masaaki; Liu, Meigen

    2010-02-01

    Herpes zoster (HZ)-induced abdominal wall pseudohernia has been frequently reported, but there has been no report describing HZ-induced trunk muscle paresis leading to functional problems. We describe a 73-year-old man with T12 and L1 segmental paresis caused by HZ presenting with abdominal wall pseudohernia, scoliosis, and standing and gait disturbance who responded well to a systematic rehabilitation approach. He first noticed a right abdominal bulge in the 6th postherpetic week, which was gradually accompanied by right convex thoracolumbar scoliosis, pain, and standing and gait disturbance in the 12th week. Needle electromyography revealed abnormal spontaneous activities at rest in the right T12 myotomal muscles, and motor unit recruitment was markedly decreased. We arranged an outpatient rehabilitation program consisting of using a soft thoracolumbosacral orthosis for pain relief and trunk stability, muscle reeducation of the paretic abdominal muscles, strengthening of the disused trunk and extremity muscles, and gait exercise. Based on electromyographic findings, we instructed him in an effective method of muscle reeducation. After 4 months of rehabilitation, he showed marked improvement and became an outdoor ambulator. We suggest that electromyography is a useful tool to evaluate clinical status and devise an effective rehabilitation program in patients with HZ trunk paresis. PMID:20159140

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

    PubMed Central

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

    2015-01-01

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

  9. Transcatheter coil embolization of the inferior epigastric artery in a huge abdominal wall hematoma caused by paracentesis in a patient with liver cirrhosis

    PubMed Central

    Park, Yun Ji; Lee, Sang Yeon; Kim, Seong Hun; Kim, In Hee; Kim, Sang Wook

    2011-01-01

    Therapeutic paracentesis is considered to be a relatively safe procedure and is performed commonly for the control of massive ascites in patients with liver cirrhosis. The commonest puncture site, approximately 4 or 5 cm medial of left anterior superior iliac spine, can be located across the route of the inferior epigastric artery, which is one of the sites of potential massive bleeding. In a 46-year-old woman with liver cirrhosis and refractory ascites, a huge abdominal wall hematoma developed after therapeutic paracentesis. The patient was not stabilized by conservative treatment, and inferior epigastric artery injury was confirmed on angiography. Angiographic coil embolization of the inferior epigastric artery was conducted, after which the bleeding ceased and the hematoma stopped growing. This case indicates that physicians performing paracentesis should be aware of the possibility of inferior epigastric artery injury and consider early angiographic coil embolization when a life-threatening abdominal wall hematoma develops. PMID:22102392

  10. A new possibility of melt cooling in extrusion dies to prevent sagging-effects in thick-walled pipes

    NASA Astrophysics Data System (ADS)

    te Heesen, O.; Wortberg, J.

    2014-05-01

    One challenge in the extrusion process of thick-walled pipes is the cooling of the product. Besides the output of the extruder, the line speed is also limited by the efficiency of the cooling line. The cooling time increases according to the wall thickness of the pipe under otherwise equal process conditions. State of the art is the cooling of the outer surface in water tanks or spray-cool-tanks. In addition to that, it is possible to cool the inner surface by air that is sucked through the pipe. Despite these technologies it is problematic to cool down thick walled-products with the right speed. Especially thick-walled pipes show problems by cooling the layers in the middle of the wall. On the one hand an intensive cooling of the outer and inner surface of the pipe entail the formation of shrink holes in the middle of the pipe wall. On the other hand without a quick cooling the melt flow in circumferential direction because of the gravity takes place (sagging-effect). Because of this reason in the presented paper new possibilities of melt cooling in extrusion dies to prevent sagging-effects are given. An aimed cooling of the inbound melt layers inside the extrusion die could prevent the effect of melt flow in circumferential direction after the extrusion die, allows the specification of a specific temperature profile over the radius of the pipe wall and helps to reduce the melt temperature for rising mass throughputs and screw driving speeds of the extruder. It is also thinkable to influence the crystallization process and thereby the mechanical properties of the end-product by an aimed cooling of the inner pipe layers.

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

    PubMed Central

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

    2016-01-01

    Background and aims The clinical results of the vertical “vest-over-pants” Mayo repair were evaluated, and the risk factors for incisional hernia recurrence were studied. The purpose of this study is to point out the importance of reducing pre and post operative risk factors in the incisional hernia repair process in order to achieve a physiologically normal abdominal wall. Methods Twenty patients diagnosed with incisional hernia underwent an abdominal reconstruction procedure using the Mayo (Paletot) technique at Bichat Claude Bernard Hospital between 2005 and 2015. All procedures were performed by a single surgeon and all patients were pre-operatively prepared, identifying all coexisting conditions and treating them accordingly before undergoing surgery. Results All patients underwent at least one surgical operation before the hernia repair procedure and a quarter had experienced at least three, prior to this one. Nine patients had a body mass index of >30 kg/m2. Additional risk factors and comorbidities included obesity in 45%, diabetes mellitus in 10%, smoking in 55%, and high blood pressure in 40%. Hernia defect width was from 3 cm (25% F) to 15 cm (5% M) of which nine patients (45%) had a 10 cm defect. Most of the patients had an average hospitalization of 7 days. The patients were carefully monitored and were called on periodic consultations after 3, 6, and 12 months from the moment of the procedure. Patient feedback regarding hernia recurrence and complaints about the scar were noted. Physical examination is essential in determining the hernia recurrence therefore the scar was examined for any abnormalities that may have occurred, which was defined as any palpable or detected fascial defect located within seven centimeters of the hernia repair. Post-operative complications: seroma formation, wound hematoma, superficial and deep wound infection, recurrences and chronic pain were followed and no complications were registered during the follow-up period. Conclusions Reducing the risk factors to a minimum prior to surgery will increase the success of the incisional hernia repair and generate a positive impact on the patient’s quality of life. The lofty goal of significant weight loss prior to elective hernia has shown to be the key factor in using the Mayo technique for incisional hernia repair. This study demonstrates that the Mayo repair technique is a suitable and trustworthy alternative for repairing incisional hernias with very good results. It’s costs are minimal and it can be easily reproduced, even by less experienced surgeons. PMID:27004034

  12. Bobbin-Tool Friction-Stir Welding of Thick-Walled Aluminum Alloy Pressure Vessels

    SciTech Connect

    Dalder, E C; Pastrnak, J W; Engel, J; Forrest, R S; Kokko, E; Ternan, K M; Waldron, D

    2007-06-06

    It was desired to assemble thick-walled Al alloy 2219 pressure vessels by bobbin-tool friction-stir welding. To develop the welding-process, mechanical-property, and fitness-for-service information to support this effort, extensive friction-stir welding-parameter studies were conducted on 2.5 cm. and 3.8 cm. thick 2219 Al alloy plate. Starting conditions of the plate were the fully-heat-treated (-T62) and in the annealed (-O) conditions. The former condition was chosen with the intent of using the welds in either the 'as welded' condition or after a simple low-temperature aging treatment. Since preliminary stress-analyses showed that stresses in and near the welds would probably exceed the yield-strength of both 'as welded' and welded and aged weld-joints, a post-weld solution-treatment, quenching, and aging treatment was also examined. Once a suitable set of welding and post-weld heat-treatment parameters was established, the project divided into two parts. The first part concentrated on developing the necessary process information to be able to make defect-free friction-stir welds in 3.8 cm. thick Al alloy 2219 in the form of circumferential welds that would join two hemispherical forgings with a 102 cm. inside diameter. This necessitated going to a bobbin-tool welding-technique to simplify the tooling needed to react the large forces generated in friction-stir welding. The bobbin-tool technique was demonstrated on both flat-plates and plates that were bent to the curvature of the actual vessel. An additional issue was termination of the weld, i.e. closing out the hole left at the end of the weld by withdrawal of the friction-stir welding tool. This was accomplished by friction-plug welding a slightly-oversized Al alloy 2219 plug into the termination-hole, followed by machining the plug flush with both the inside and outside surfaces of the vessel. The second part of the project involved demonstrating that the welds were fit for the intended service. This involved determining the room-temperature tensile and elastic-plastic fracture-toughness properties of the bobbin-tool friction-stir welds after a post-weld solution-treatment, quenching, and aging heat-treatment. These mechanical properties were used to conduct fracture-mechanics analyses to determine critical flaw sizes. Phased-array and conventional ultrasonic non-destructive examination was used to demonstrate that no flaws that match or exceed the calculated critical flaw-sizes exist in or near the friction-stir welds.

  13. The interaction of moderately strong shock waves with thick perforated walls of low porosity

    NASA Technical Reports Server (NTRS)

    Grant, D. J.

    1972-01-01

    A theoretical prediction is given of the flow through thick perforated walls of low porosity resulting from the impingement of a moderately strong traveling shock wave. The model was a flat plate positioned normal to the direction of the flow. Holes bored in the plate parallel to the direction of the flow provided nominal hole length-to-diameter ratios of 10:1 and an axial porosity of 25 percent of the flow channel cross section. The flow field behind the reflected shock wave was assumed to behave as a reservoir producing a quasi-steady duct flow through the model. Rayleigh and Fanno duct flow theoretical computations for each of three possible auxiliary wave patterns that can be associated with the transmitted shock (to satisfy contact surface compatibility) were used to provide bounding solutions as an alternative to the more complex influence coefficients method. Qualitative and quantitative behavior was verified in a 1.5- by 2.0-in. helium shock tube. High speed Schlieren photography, piezoelectric pressure-time histories, and electronic-counter wave speed measurements were used to assess the extent of correlation with the theoretical flow models. Reduced data indicated the adequacy of the bounding theory approach to predict wave phenomena and quantitative response.

  14. Modeling Periodic Adiabatic Shear Bands Evolution in a 304L Stainless Steel Thick-Walled Cylinder

    NASA Astrophysics Data System (ADS)

    Liu, Mingtao; Hu, Haibo; Fan, Cheng; Tang, Tiegang

    2015-06-01

    The self-organization of multiple shear bands in a 304L stainless steel thick-walled cylinder (TWC) was numerically studied. The microstructures of material lead to the non-uniform distribution of local yield stress, which plays a key role in the formation of spontaneous shear localization. We introduced a probability factor satisfied Gauss distribution into the macroscopic constitutive relationship to describe the non-uniformity of local yield stress. Using the probability factor, the initiation and propagation of multiple shear bands in TWC were numerically replicated in our 2D FEM simulation. Experimental results in the literature indicate that the machined surface at the internal boundary of a 304L stainless steel cylinder provides a work-hardened layer (about 20 μm) which has significantly different microstructures from base material. The work-hardened layer leads to the phenomenon that most shear bands are in clockwise or counterclockwise direction. In our simulation, periodic oriented perturbations were applied to describe the grain orientation in the work-hardened layer, and the spiral pattern of shear bands was successfully replicated.

  15. Chest wall thickness measurements and the dosimetric implications for male workers in the south Korean uranium industry.

    PubMed

    Kramer, G H; Lee, T Y; Lee, J I; Chang, S Y

    2001-01-01

    Using ultrasound techniques, the Human Monitoring Laboratory has measured chest wall thicknesses of a group of male workers at the Korea Atomic Energy Research Institute. A site-specific biometric equation has been developed for these workers, who are somewhat smaller than other workers reported in the literature. Chest wall thickness is an important modifier on lung counting efficiency. These data have been put into the perspective of the ICRP recommended dose limits for occupationally exposed workers: 100 mSv in a 5-year period with a maximum of 50 mSv in any one year. For measured chest wall thicknesses of 1.9 cm to 4.1 cm and a 30 min counting time, the achievable MDAs for natural uranium in the KAERI lung counter vary from 6.6 mg to 13.2 mg. These values are close to, or even exceed, the predicted amounts of natural uranium that will remain in the lung (absorption type M and S) after an intake equal to the Annual Limit on Intake corresponding to a committed dose of 20 mSv. This paper shows that the KAERI lung counter probably cannot detect an intake of Type S natural uranium in a worker with a chest wall thickness equal to the average value (2.7 cm) under routine counting conditions. PMID:11468802

  16. Computer-aided detection of bladder tumors based on the thickness mapping of bladder wall in MR images

    NASA Astrophysics Data System (ADS)

    Zhu, Hongbin; Duan, Chaijie; Jiang, Ruirui; Li, Lihong; Fan, Yi; Yu, Xiaokang; Zeng, Wei; Gu, Xianfeng; Liang, Zhengrong

    2010-03-01

    Bladder cancer is reported to be the fifth leading cause of cancer deaths in the United States. Recent advances in medical imaging technologies, such as magnetic resonance (MR) imaging, make virtual cystoscopy a potential alternative with advantages as being a safe and non-invasive method for evaluation of the entire bladder and detection of abnormalities. To help reducing the interpretation time and reading fatigue of the readers or radiologists, we introduce a computer-aided detection scheme based on the thickness mapping of the bladder wall since locally-thickened bladder wall often appears around tumors. In the thickness mapping method, the path used to measure the thickness can be determined without any ambiguity by tracing the gradient direction of the potential field between the inner and outer borders of the bladder wall. The thickness mapping of the three-dimensional inner border surface of the bladder is then flattened to a twodimensional (2D) gray image with conformal mapping method. In the 2D flattened image, a blob detector is applied to detect the abnormalities, which are actually the thickened bladder wall indicating bladder lesions. Such scheme was tested on two MR datasets, one from a healthy volunteer and the other from a patient with a tumor. The result is preliminary, but very promising with 100% detection sensitivity at 7 FPs per case.

  17. SMAD3 deficiency promotes vessel wall remodeling, collagen fiber reorganization and leukocyte infiltration in an inflammatory abdominal aortic aneurysm mouse model

    PubMed Central

    Dai, Xiaohua; Shen, Jianbin; Priyanka Annam, Neeraja; Jiang, Hong; Levi, Edi; Schworer, Charles M.; Tromp, Gerard; Arora, Anandita; Higgins, Mary; Wang, Xiao-Fan; Yang, Maozhou; Li, Hui J.; Zhang, Kezhong; Kuivaniemi, Helena; Li, Li

    2015-01-01

    TGF-β signaling plays critical roles in the pathogenesis of aneurysms; however, it is still unclear whether its role is protective or destructive. In this study, we investigate the role of SMAD3 in the pathogenesis of calcium chloride (CaCl2)-induced abdominal aortic aneurysms (AAA) in Smad3−/−, Smad3+/− and Smad3+/+ mice. We find that loss of SMAD3 drastically increases wall thickening of the abdominal aorta. Histological analyses show significant vessel wall remodeling with elastic fiber fragmentation. Remarkably, under polarized light, collagen fibers in the hyperplastic adventitia of Smad3−/− mice show extensive reorganization accompanied by loosely packed thin and radial collagen fibers. The expressions of matrix metalloproteinases including MMP2, MMP9, and MMP12 and infiltration of macrophage/T cells are drastically enhanced in the vascular wall of Smad3−/− mice. We also observe marked increase of NF-κB and ERK1/2 signaling as well as the expression of nuclear Smad2, Smad4 and TGF-β1 in the vessel wall of Smad3−/− mice. In addition, we find that SMAD3 expression is reduced in the dedifferentiated medial smooth muscle-like cells of human AAA patients. These findings provide direct in vivo evidence to support the essential roles of SMAD3 in protecting vessel wall integrity and suppressing inflammation in the pathogenesis of AAAs. PMID:25985281

  18. Abdominal sepsis managed by leaving abdomen open.

    PubMed

    Duff, J H; Moffat, J

    1981-10-01

    Intra-abdominal sepsis and necrotizing infection of the abdominal wall are usually fatal unless adequate drainage and wide debridement are possible. To follow these principles, we managed 18 seriously ill patients with abdominal sepsis by leaving the abdomen completely open. All except two of the patients had severe intra-abdominal sepsis. Eight patients had full-thickness wound infections and intra-abdominal infections refractory to the usual surgical drainage techniques. Two had necrotizing wound infections only. In 12 an upper abdominal incision was managed open, and in six the open incision was lower. As part of the initiating illness, there were eight small bowel and six colon fistulas. They were managed by colostomy in five patients and ileostomy in two. More than one organism was cultured in all patients and 12 of 18 had a positive blood culture. Respiratory failure made mechanical ventilation necessary in 13 patients for an average of 44 days. Previous adhesions, usually present, or an intact greater omentum, were necessary to prevent bowel evisceration, but three patients required paralysis and mechanical ventilation until adhesions became strong enough to prevent evisceration. There were seven deaths (39%), six caused by continuing sepsis and one from hemorrhage. In those surviving, granulation tissue grew over omentum or bowel loops to eventually seal the abdominal cavity. The late management was split-skin grafting in five and secondary closure in two. Four healed by second intention. We conclude that leaving the abdomen completely open facilitates the widest possible drainage, uncompromising debridement of the abdominal wall, and is compatible with good recovery. The ultimate result in survivors is acceptable. This technique is preferable to closing an abdominal wall of questionable viability in the face of intraperitoneal sepsis. PMID:6456563

  19. Left anterior descending coronary artery wall thickness measured by high-frequency transthoracic and epicardial echocardiography includes adventitia.

    PubMed

    Gradus-Pizlo, Irmina; Bigelow, Brian; Mahomed, Yousuf; Sawada, Stephen G; Rieger, Karen; Feigenbaum, Harvey

    2003-01-01

    High-frequency, 2-dimensional transthoracic echocardiography (HR-2DTTE) measurements of the left anterior descending (LAD) coronary artery wall thickness are larger than measurements obtained by intravascular ultrasound. We hypothesize that this difference is due to inclusion of the third vascular layer, which may represent adventitia by HR-2DTTE, and that this layer must be increasing in thickness with the development of atherosclerosis. We evaluated the contribution of this third layer to the wall thickness of the normal and atherosclerotic LAD artery imaged by HR-2DTTE using high-frequency epicardial echocardiography (HFEE) as the reference standard. Eighteen patients (10 men, mean age 62 years), 13 with coronary atherosclerosis and 5 with normal coronary arteries, referred for open-heart surgery, underwent preoperative HR-2DTTE evaluation of the LAD artery (SONOS 5500; 3- to 8-MHz transducer) and intraoperative HFEE of the LAD artery (SONOS 5500; 6- to 15-MHz transducer). Wall thickness was greater in patients with coronary atherosclerosis than in those with normal coronary arteries by both HR-2DTTE (1.9 +/- 0.3 vs 1.0 +/- 0.1 mm, p = <0.001) and HFEE (1.8 +/- 0.2 vs 1.0 +/- 0.2 mm, p = <0.001). On HFEE, the average intima plus media thickness was greater in patients with coronary atherosclerosis than in those with normal coronary arteries (0.78 +/- 0.3 vs 0.34 +/- 0.1 mm, p = 0.005). The average thickness of adventitia was also greater in patients with coronary atherosclerosis than in those with normal coronary arteries (0.92 +/- 0.2 vs 0.54 +/- 0.2 mm, p = 0.0005). HR-2DTTE and HFEE measurements of the wall thickness correlated well (r = 0.83 [reader 1], p <0.001; r = 0.61 [reader 2], p <0.01). A third vascular layer, which likely included adventitia, represents a significant portion of the LAD wall thickness imaged by HR-2DTTE and HFEE, and it significantly increases in thickness with the development of atherosclerosis. PMID:12505567

  20. The uncertainty in the activity estimate from a lung count due to the variability in chest wall thickness profile.

    PubMed

    Kramer, G H; Crowley, P; Burns, L C

    2000-06-01

    Calibration of a lung counter requires the use of a realistic torso phantom. The depth profile of both torso phantoms' (LLNL and JAERI) chest plate covers is fixed and assumed to be equivalent to a person's chest wall; however, ultrasound measurements of humans have shown this to be an approximation. When the depth profile of a calibration phantom is different from that of a subject, then a systematic uncertainty will be introduced into the activity estimate. Monte Carlo simulation has shown that changes in the depth profile of the chest wall thickness affect the counting efficiency. Ultrasound measurements have suggested that the coefficient of variation in the depth profile of the chest wall thickness lies between 13% and 26% for male workers; therefore, the added uncertainty to an activity estimate will be an over or underestimate of about a factor of 1.07 resulting from the different depth profile. The factor will be somewhat higher for females, probably about 1.2 at the extreme. These additional uncertainties resulting from depth profile differences are small compared with other uncertainties commonly encountered in lung counting: detector positioning, deposition patterns of the activity, measurement of the chest wall thickness, etc. PMID:10832936

  1. Measurement of three-dimensional normal vectors, principal curvatures, and wall thickness of the heart using cine-MRI

    NASA Astrophysics Data System (ADS)

    Coghlan, Leslie; Singleton, H. R.; Dell'Italia, L. J.; Linderholm, C. E.; Pohost, G. M.

    1995-05-01

    We have developed a method for measuring the detailed in vivo three dimensional geometry of the left and right ventricles using cine-magnetic resonance imaging. From data in the form of digitized short axis outlines, the normal vectors, principal curvatures and directions, and wall thickness were computed. The method was evaluated on simulated ellipsoids and on human MRI data. Measurements of normal vectors and of wall thickness were very accurate in simulated data and appeared appropriate in patient data. On simulated data, measurements of the principal curvature k1 (corresponding approximately to the short axis direction of the left ventricle) and of principal directions were quite accurate, but measurements of the other principal curvature (k2) were less accurate. The reasons behind this are considered. We expect improvements in the accuracy with thinner slices and improved representation of the surface data. Gradient echo images were acquired from 8 dogs with a 1.5T system (Philips Gyroscan) at baseline and four months after closed chest experimentally produced mitral regurgitation (MR). The product (k1 + k2) X wall thickness averaged over all slices at end-diastole was significantly lower after surgery (n equals 8, p < 0.005). These geometry changes were consistent with the expected increase in wall stress after MR.

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

    PubMed Central

    2014-01-01

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

  3. Sarcocystis sinensis is the most prevalent thick-walled Sarcocystis species in beef on sale for consumers in Germany.

    PubMed

    Moré, G; Pantchev, A; Skuballa, J; Langenmayer, M C; Maksimov, P; Conraths, F J; Venturini, M C; Schares, G

    2014-06-01

    Bovines are intermediate hosts of Sarcocystis cruzi, Sarcocystis hirsuta, and Sarcocystis hominis, which use canids, felids, or primates as definitive hosts, respectively. Cattle represent also intermediate hosts of Sarcocystis sinensis, but the definitive hosts of this parasite are not yet known. Sarcocystosis in cattle is frequently asymptomatic. The infection is characterized by the presence of thin-walled (S. cruzi) or thick-walled muscle cysts or sarcocysts (S. hominis, S. sinensis, and S. hirsuta). Recent reports suggest high prevalence of the zoonotic S. hominis in beef in Europe. We therefore aimed at differentiating Sarcocystis spp. in beef offered to consumers in Germany using molecular and microscopical methods, focusing on those species producing thick-walled sarcocysts. A total of 257 beef samples were obtained from different butcheries and supermarkets in Germany and processed by conventional and multiplex real-time PCR. In addition, 130 of these samples were processed by light microscopy and in 24.6% thick-walled cysts were detected. Transmission electron microscopical analysis of six of these samples revealed an ultrastructural cyst wall pattern compatible with S. sinensis in five samples and with S. hominis in one sample. PCR-amplified 18S ribosomal DNA (rDNA) fragments of 28 individual thick-walled cysts were sequenced, and sequence identities of ≥98% with S. sinensis (n = 22), S. hominis (n = 5) and S. hirsuta (n = 1) were observed. Moreover, nine Sarcocystis sp. 18S rDNA full length gene sequences were obtained, five of S. sinensis, three of S. hominis, and one of S. hirsuta. Out of all samples (n = 257), 174 (67.7%) tested positive by conventional PCR and 179 (69.6%) by multiplex real-time PCR for Sarcocystis spp. Regarding individual species, 134 (52%), 95 (37%), 17 (6.6%), and 16 (6.2%) were positive for S. cruzi, S. sinensis, S. hirsuta, and S. hominis, respectively. In conclusion, S. sinensis is the most prevalent thick-walled Sarcocystis species in beef offered for consumption in Germany. Further studies are needed to identify the final host of S. sinensis as well as the potential role of this protozoan as a differential diagnosis to the zoonotic species S. hominis. PMID:24700022

  4. Biometric estimation of chest wall thickness of female radiation workers as an aid in in-vivo detection of the actinides

    SciTech Connect

    Lane, B.H.; Berger, C.D.

    1983-01-01

    An equation was derived to estimate female chest wall thickness from a series of biometric measurements. This technique will result in improved performance for actinide detection in females by accounting for variations in chest wall thickness in derivation of calibration factors.

  5. Necrotizing fasciitis: literature review of contemporary strategies for diagnosing and management with three case reports: torso, abdominal wall, upper and lower limbs

    PubMed Central

    2011-01-01

    Necrotizing fasciitis (NF) is an uncommon soft tissue infection, usually caused by toxin-producing virulent bacteria. It is characterized by widespread fascial necrosis primarily caused by Streptococcus hemolyticus. Shortly after the onset of the disease, patients become colonized with their own aerobic and anaerobic microflora from the gastrointestinal and/or urogenital tracts. Early diagnosis with aggressive multidisciplinary treatment is mandatory. We describe three clinical cases with NF. The first is a 69 years old man with diabetes mellitus type II, who presented with NF on the posterior chest wall, shoulder and arm. He was admitted to the intensive care unit (ICU) with a clinical picture of severe sepsis. Outpatient treatment and early surgical debridement of the affected zones (inside 3 hours after admittance) and critical care therapy were performed. The second case is of a 63 years old paraplegic man with diabetes mellitus type I. Pressure sores and perineal abscesses progressed to Fournier's gangrene of the perineum and scrotum. He had NF of the anterior abdominal wall and the right thigh. Outpatient treatment and early surgical debridement of the affected zones (inside 6 hour after admittance) and critical care therapy were performed. The third patient was a 56 year old man who had NF of the anterior abdominal wall, flank and retroperitoneal space. He had an operation of the direct inguinal hernia, which was complicated with a bowel perforation and secondary peritonitis. After establishing the diagnosis of NF of the abdominal wall and retroperitoneal space (RS), he was transferred to the ICU. There he first received intensive care therapy, after which emergency surgical debridement of the abdominal wall, left colectomy, and extensive debridement of the RS were done (72 hours after operation of inquinal hernia). On average, 4 serial debridements were performed in each patient. The median of serial debridement in all three cases was four times. Other intensive care therapy with a combination of antibiotics and adjuvant hyperbaric oxygen therapy (HBOT) was applied during the treatment. After stabilization of soft tissue wounds and the formation of fresh granulation tissue, soft tissue defect were reconstructed using simple to complex reconstructive methods. PMID:22196774

  6. Enhanced film thickness for Néel wall in soft magnetic film by introducing strong magnetocrystalline anisotropy

    PubMed Central

    Xu, Fei; Wang, Tao; Ma, Tianyong; Wang, Ying; Zhu, Shimeng; Li, Fashen

    2016-01-01

    This study investigated the magnetic domain walls in a single-layer soft magnetic film with strong magnetocrystalline anisotropy energy. The soft magnetic film is composed of a highly c-axis-oriented hcp-Co81Ir19 alloy with strong negative magnetocrystalline anisotropy. The domain structure of the soft Co81Ir19 films with thickness ranging from 50–230 nm in a demagnetization state was observed through magnetic force microscopy and Lorentz transmission electron microscopy. Results reveal that the critical transition thickness at which the domain wall changes from Néel type to Bloch type is about 138 nm, which is much larger than the critical value of traditional Fe- and Co-based soft magnetic films with negligible magnetocrystalline anisotropy. Theoretical calculation was also performed and the calculated result agrees well with experimental data. PMID:26821614

  7. Model and numerical simulation for the evolution of residual wall thickness in Water-Assisted Injection Molding

    NASA Astrophysics Data System (ADS)

    Li, Qian; Cao, Wei; Zhang, Shixun; Shen, Changyu

    2010-06-01

    The motion of water-melt interface confined in horizontal circular tubes during Water-Assisted Injection Molding (WAIM) has been studied both theoretically and experimentally. Of particular interest is the determination of residual melt film thickness on the walls. The reduced governing equations for viscous compressible non-Newtonian polymer melt during the second penetration in WAIM were established using dimensionless method. A formula used to calculate the second penetrating velocity was derived based on mathematical inference and mechanical principle. Experiments was conducted to measure the displacement of the water-melt interface as a function of the melt temperature, water pressure. The experimental results indicate the first penetration theory is not accurate in predicting residual wall thickness and the combined first and second penetration theories can improve the accuracy significantly.

  8. Enhanced film thickness for Néel wall in soft magnetic film by introducing strong magnetocrystalline anisotropy.

    PubMed

    Xu, Fei; Wang, Tao; Ma, Tianyong; Wang, Ying; Zhu, Shimeng; Li, Fashen

    2016-01-01

    This study investigated the magnetic domain walls in a single-layer soft magnetic film with strong magnetocrystalline anisotropy energy. The soft magnetic film is composed of a highly c-axis-oriented hcp-Co81Ir19 alloy with strong negative magnetocrystalline anisotropy. The domain structure of the soft Co81Ir19 films with thickness ranging from 50-230 nm in a demagnetization state was observed through magnetic force microscopy and Lorentz transmission electron microscopy. Results reveal that the critical transition thickness at which the domain wall changes from Néel type to Bloch type is about 138 nm, which is much larger than the critical value of traditional Fe- and Co-based soft magnetic films with negligible magnetocrystalline anisotropy. Theoretical calculation was also performed and the calculated result agrees well with experimental data. PMID:26821614

  9. Using The Descending Aortic Wall Thickness Measured In Transesophageal Echocardiography As A Risk Marker For Aortic Dissection

    PubMed Central

    Fanari, Zaher; Hammami, Sumaya; Hammami, Muhammad Baraa; Hammami, Safa; Eze-Nliam, Chete; Weintraub, William S.

    2015-01-01

    Objective The aim of this study is to estimate whether aortic wall thickness is increased in patients with Aortic dissection (AD) compared to low risk control group and can be used in addition to aortic diameter as a risk marker of AD. Background AD occurs due to pathologies that may increase thickness of the aortic wall. Transesophageal echocardiography (TEE) has the ability to visualize both the thoracic aortic wall and lumen. Aortic diameter has been used to predict aortic dissection and timing of surgery, but it is not always predictive of that risk. Methods In 48 patients with AD who underwent TEE were examined retrospectively and compared to 48 control patients with patent foramen ovale (PFO). We measured aortic diameter at different levels, intimal/medial thickness (IMT) and complete wall thickness (CMT). Demographic data and cardiovascular risk factors were reviewed. The data was analyzed using ANOVA and student t test. Results (AD) patients were older [mean age 66 AD vs. 51 PFO], had more hypertension, diabetes, hyperlipidemia and Coronary artery disease. Both IMT and CMT in the descending aorta were increased in AD group [(1.85 vs. 1.43 mm; P=0.03 and 2.93 vs. 2.46 mm; p=0.01). As expected the diameter of ascending aorta was also greater in AD (4.61 vs. 2.92 cm; P=0.004). Conclusions CMT and IMT in the descending aorta detected by TEE is greater in patients with AD when compared to control and may add prognostic data to that of aortic diameter. PMID:25984293

  10. Dimensionless analysis of valveless pumping in a thick-wall elastic tube: Application to the tubular embryonic heart.

    PubMed

    Kozlovsky, Pavel; Rosenfeld, Moshe; Jaffa, Ariel J; Elad, David

    2015-06-25

    The physical mechanism that drives blood flow in the valveless tubular embryonic heart is still debatable whether it is peristaltic flow or valveless dynamic suction. Previous studies of valveless pumping were concerned with either the role of the excitation parameters or the mechanisms that generate the unidirectional outflow. In this study, a dimensionless one-dimensional (1D) analysis of the valveless pumping due to local excitation at an asymmetric longitudinal location was performed for non-uniform thick-wall elastic tubes, including tubes with local bulging and tapering. A general tube law that accounts for wall thicknesses was implemented for describing the physically realistic dynamics of the tube and the two-step MacCormack algorithm was utilized for the numerical analysis. A comprehensive analysis was conducted to explore the affecting roles of the system (e.g., tube geometry) and the working (e.g., Strouhal number and flow friction parameter) parameters on the net outflow of the pump. The maximal positive net outflow in all the tested cases always occurred when the natural Strouhal number was about π. Flow reversals were observed only for relatively low friction parameters. A local bulging at the site of excitation and thick walls contributed to larger outflows, while tube tapering reduced the net outflow. PMID:25835790

  11. Shear flow over a plane wall with an axisymmetric cavity or a circular orifice of finite thickness

    NASA Astrophysics Data System (ADS)

    Pozrikidis, C.

    1994-01-01

    Shear flow over a plane wall that contains an axisymmetric depression or pore is studied using a new boundary integral method which is suitable for computing three-dimensional Stokes flow within axisymmetric domains. Numerical results are presented for cavities in the shape of a section of a sphere or a circular cylinder of finite length, and for a family of pores or orifices with finite thickness. The results illustrate the distribution of shear stresses over the plane wall and inside the cavities or pores. It is found that in most cases, the distribution of shear stresses over the plane wall, around the depressions, is well approximated with that for flow over an orifice of infinitesimal thickness for which an exact solution is available. The kinematic structure of the flow is discussed with reference to eddy formation and three-dimensional flow reversal. It is shown that the thickness of a circular orifice or depth of a pore play an important role in determining the kinematical structure of the flow underneath the orifice in the lower half-space.

  12. Omental infarction and its mimics: imaging features of acute abdominal conditions presenting with fat stranding greater than the degree of bowel wall thickening.

    PubMed

    Tonerini, Michele; Calcagni, Francesca; Lorenzi, Silvia; Scalise, Paola; Grigolini, Alessandro; Bemi, Pietro

    2015-08-01

    The segmental omental infarction is a rare self-limited disorder presenting with aspecific clinical symptoms that may mimic several acute abdominal conditions. Therefore, a correct noninvasive diagnosis is important because treatment approaches range from monitoring to surgery. As omental infarction results in an important fat stranding that is much greater than the degree of bowel wall thickening, it suggests a narrower differential diagnosis: appendicitis, diverticulitis, epiploic appendagitis, and mesenteric panniculitis. In this pictorial essay, we point out the importance of imaging in identifying this typical sign allowing alternate diagnoses such as segmental omental infarction that can be conservatively managed. PMID:25725796

  13. Extracorporeal bypass preserved composite anterior thigh free flap (periosteo-musculo-fascio-cutaneous) for hemipelvectomy reconstruction: utilizing the periosteal component for abdominal wall fascial reconstruction.

    PubMed

    Newsome, R Edward; Warner, Meredith A; Wilson, Scott C; Sabeeh, Vasif N; Jansen, David A; McKee, Paul R

    2005-03-01

    We present a case of a right external hemipelvectomy for chondroblastic osteosarcoma originating from the right ilium and reconstruction with salvage parts; cardiopulmonary bypass preserved anterior thigh free flap. The resection required sacrifice of the right common iliac artery and vein and the entire right gluteus maximus muscle. The first stage of the procedure was a high above-knee amputation on the ipsilateral leg. The amputated extremity was placed on extracorporeal bypass utilizing the common femoral artery and vein. This technique, previously unreported, supported the successful utilization of the anterior thigh free flap for both soft tissue and abdominal wall facial reconstruction. PMID:15725844

  14. Recombinant human bone morphogenetic protein 2-induced heterotopic ossification of the retroperitoneum, psoas muscle, pelvis and abdominal wall following lumbar spinal fusion.

    PubMed

    Shah, Raj K; Moncayo, Valeria M; Smitson, Robert D; Pierre-Jerome, Claude; Terk, Michael R

    2010-05-01

    A 45-year-old man presented with vertebral collapse at L5 as an initial manifestation of multiple myeloma and underwent spinal fusion surgery using recombinant human bone morphogenetic protein-2 (rhBMP-2). Subsequent computed tomography (CT) scans and X-rays revealed heterotopic ossification of the left psoas muscle, pelvis, and anterior abdominal wall. While the occurrence of heterotopic ossification has previously been reported when rhBMP-2 has been used for spinal fusion surgery, this case demonstrates that it can occur to a much greater degree than previously seen. PMID:20162273

  15. Diffusion capacity and CT measures of emphysema and airway wall thickness – relation to arterial oxygen tension in COPD patients

    PubMed Central

    Saure, Eirunn Waatevik; Bakke, Per Sigvald; Eagan, Tomas Mikal Lind; Aanerud, Marianne; Jensen, Robert Leroy; Grydeland, Thomas Blix; Johannessen, Ane; Nilsen, Roy Miodini; Thorsen, Einar; Hardie, Jon Andrew

    2016-01-01

    Background Decreased diffusing capacity of the lung for carbon monoxide (DLCO) is associated with emphysema. DLCO is also related to decreased arterial oxygen tension (PaO2), but there are limited data on associations between PaO2 and computed tomography (CT) derived measures of emphysema and airway wall thickness. Objective To examine whether CT measures of emphysema and airway wall thickness are associated with level of arterial oxygen tension beyond that provided by measurements of diffusion capacity and spirometry. Methods The study sample consisted of 271 smoking or ex-smoking COPD patients from the Bergen COPD Cohort Study examined in 2007–2008. Emphysema was assessed as percent of low-attenuation areas<−950 Hounsfield units (%LAA), and airway wall thickness as standardised measure at an internal perimeter of 10 mm (AWT-Pi10). Multiple linear regression models were fitted with PaO2 as the outcome variable, and %LAA, AWT-Pi10, DLCO and carbon monoxide transfer coefficient (KCO) as main explanatory variables. The models were adjusted for sex, age, smoking status, and haemoglobin concentration, as well as forced expiratory volume in one second (FEV1). Results Sixty two per cent of the subjects were men, mean (SD) age was 64 (7) years, mean (SD) FEV1 in percent predicted was 50 (15)%, and mean PaO2 (SD) was 9.3 (1.1) kPa. The adjusted regression coefficient (CI) for PaO2 was –0.32 (−0.04–(−0.019)) per 10% increase in %LAA (p<0.01). When diffusion capacity and FEV1 were added to the model, respectively, the association lost its statistical significance. No relationship between airway wall thickness and PaO2 was found. Conclusion CT assessment of airway wall thickness is not associated with arterial oxygen tension in COPD patients. Emphysema score measured by chest CT, is related to decreased PaO2, but cannot replace measurements of diffusion capacity in the clinical evaluation of hypoxaemia. PMID:27178139

  16. Recommendations for protecting against failure by brittle fracture: Category II and III ferritic steel shipping containers with wall thickness greater than four inches

    SciTech Connect

    Schwartz, M.W.; Fischer, L.E.

    1996-08-01

    This report provides criteria for selecting ferritic steels that would prevent brittle fracture in Category II and III shipping containers with wall thickness greater than 4 inches. These methods are extensions of those previously used for Category II and III containers less than 4 inches thick and Category I containers more than 4 inches thick.

  17. Ultrasound-Derived Abdominal Muscle Thickness Better Detects Metabolic Syndrome Risk in Obese Patients than Skeletal Muscle Index Measured by Dual-Energy X-Ray Absorptiometry

    PubMed Central

    Ido, Ayumi; Nakayama, Yuki; Ishii, Kojiro; Iemitsu, Motoyuki; Sato, Koji; Fujimoto, Masahiro; Kurihara, Toshiyuki; Hamaoka, Takafumi; Satoh-Asahara, Noriko; Sanada, Kiyoshi

    2015-01-01

    Sarcopenia has never been diagnosed based on site-specific muscle loss, and little is known about the relationship between site-specific muscle loss and metabolic syndrome (MetS) risk factors. To this end, this cross-sectional study aimed to investigate the relationship between site-specific muscle size and MetS risk factors. Subjects were 38 obese men and women aged 40–82 years. Total body fat and lean body mass were assessed by whole-body dual-energy X-ray absorptiometry (DXA) scan. Muscle thickness (MTH) was measured using B-mode ultrasound scanning in six body regions. Subjects were classified into general obesity (GO) and sarcopenic obesity (SO) groups using the threshold values of one standard deviation below the sex-specific means of either MTH or skeletal muscle index (SMI) measured by DXA. MetS risk score was acquired by standardizing and summing the following continuously distributed variables: visceral fat area, mean blood pressure, HbA1c, and serum triglyceride / high density lipoprotein cholesterol, to obtain the Z-score. Multiple regression analysis revealed that the MetS risk score was independently associated with abdominal MTH in all subjects, but not with MTH in other muscle regions, including the thigh. Although HbA1c and the number of MetS risk factors in the SO group were significantly higher than those in the GO group, there were no significant differences between GO and SO groups as defined by SMI. Ultrasound-derived abdominal MTH would allow a better assessment of sarcopenia in obese patients and can be used as an alternative to the conventionally-used SMI measured by DXA. PMID:26700167

  18. Automatic airway wall segmentation and thickness measurement for long-range optical coherence tomography images.

    PubMed

    Qi, Li; Huang, Shenghai; Heidari, Andrew E; Dai, Cuixia; Zhu, Jiang; Zhang, Xuping; Chen, Zhongping

    2015-12-28

    We present an automatic segmentation method for the delineation and quantitative thickness measurement of multiple layers in endoscopic airway optical coherence tomography (OCT) images. The boundaries of the mucosa and the sub-mucosa layers are accurately extracted using a graph-theory-based dynamic programming algorithm. The algorithm was tested with sheep airway OCT images. Quantitative thicknesses of the mucosal layers are obtained automatically for smoke inhalation injury experiments. PMID:26832057

  19. A Review of Thermal Conductivity of Polymer Matrix Syntactic Foams—Effect of Hollow Particle Wall Thickness and Volume Fraction

    NASA Astrophysics Data System (ADS)

    Gupta, Nikhil; Pinisetty, Dinesh

    2013-02-01

    Hollow-particle-filled composites called syntactic foams are lightweight particulate composites that are useful in weight-sensitive applications such as aerospace and marine structures. Extensive literature is now available on the mechanical properties of syntactic foams. The upcoming applications for syntactic foams in aerospace structures require understanding of their thermal properties, such as the thermal conductivity. The present review article summarizes the available experimental results and theoretical models related to the thermal conductivity of syntactic foams. Experimental results are available for only a few compositions of syntactic foams. Basic understating of the relationship between thermal conductivity of syntactic foams and the material parameters, such as hollow particle volume fraction and wall thickness, is not available through experimental results at this point. Four theoretical models are tested with the experimental data and found to provide close predictions. These models are used to conduct parametric studies. It is observed that the thermal conductivity of syntactic foams decreases as the volume fraction of thin-walled particles is increased. An inverse relationship is observed for thick-walled, hollow-particle-filled syntactic foams. These models can help in designing syntactic foams with required thermal conductivity.

  20. Measure Guideline: Incorporating Thick Layers of Exterior Rigid Insulation on Walls

    SciTech Connect

    Lstiburek, Joseph; Baker, Peter

    2015-04-01

    This measure guideline provides information about the design and construction of wall assemblies that use layers of rigid exterior insulation thicker than 1-½ inches and that require a secondary cladding attachment location exterior to the insulation. The guideline is separated into several distinct sections that cover: fundamental building science principles relating to the use of exterior insulation on wall assemblies; design principles for tailoring this use to the specific project goals and requirements; and construction detailing to increase understanding about implementing the various design elements.

  1. Measure Guideline. Incorporating Thick Layers of Exterior Rigid Insulation on Walls

    SciTech Connect

    Lstiburek, Joseph; Baker, Peter

    2015-04-09

    This measure guideline, written by the U.S. Department of Energy’s Building America team Building Science Corporation, provides information about the design and construction of wall assemblies that use layers of rigid exterior insulation thicker than 1-½ in. and that require a secondary cladding attachment location exterior to the insulation. The guideline is separated into several distinct sections that cover: (1) fundamental building science principles relating to the use of exterior insulation on wall assemblies; (2) design principles for tailoring this use to the specific project goals and requirements; and (3) construction detailing to increase understanding about implementing the various design elements.

  2. Abdominal Adhesions

    MedlinePlus

    ... tissue that can form between abdominal tissues and organs. [ Top ] What is the abdominal cavity? The abdominal cavity is the internal area of ... tissues and organs. Abdominal adhesions cause tissues and organs in the abdominal cavity to stick together. Abdominal surgery is the most ...

  3. Abdominal Adhesions

    MedlinePlus

    ... body moves. However, abdominal adhesions cause tissues and organs in the abdominal cavity to stick together. What is the abdominal cavity? ... tissues and organs. Abdominal adhesions cause tissues and organs in the abdominal cavity to stick together. • Abdominal surgery is the most ...

  4. The gender-specific chest wall thickness prediction equations for routine measurements of {sup 239}Pu and {sup 241}Am within the lungs using HPGE detectors

    SciTech Connect

    Vickers, L.R.

    1996-03-01

    The current chest wall thickness prediction equation is not applicable to use in routine lung counting measurements for detection of low energy photons (17-60 keV) within the lungs of male and female subjects. The current chest wall thickness prediction equation was derived for the NaI-CsI {open_quotes}phoswich{close_quotes} detection system, which is not the routine detection system in use; the subject position was supine, which is not the routine position; the equation did not account for the intercostal tissue thicknesses of muscle and adipose which significantly attenuate low energy photons (17-60 keV); it was derived from male subjects only and is used to predict the chest wall thickness of female subjects for whom it is not applicable. The current chest wall thickness prediction equation yields unacceptable percent errors in the HPGe detection efficiency calibration for {sup 239}Pu and {sup 241}Am (17- and 59.5-keV photons, respectively) relative to the gender-specific HPGe chest wall thickness prediction equations of this paper (+284% to -73% for {sup 239}Pu; +42% to -39% for {sup 241}Am). As a result, use of the current chest wall thickness prediction equation yields unacceptable percent errors (proportional in magnitude to the percent errors in the detection efficiency calibration) in the calculation of the minimum detectable activity (Bq) or in an initial assessment of a radioactive contamination exposure detected by a routine lung count measurement. 17 refs., 6 figs., 12 tabs.

  5. Ureteral wall thickness at the impacted ureteral stone site: a critical predictor for success rates after SWL.

    PubMed

    Sarica, Kemal; Kafkasli, Alper; Yazici, Özgür; Çetinel, Ali Cihangir; Demirkol, Mehmet Kutlu; Tuncer, Murat; Şahin, Cahit; Eryildirim, Bilal

    2015-02-01

    The aim of the study was to determine the possible predictive value of certain patient- and stone-related factors on the stone-free rates and auxiliary procedures after extracorporeal shock wave lithotripsy in patients with impacted proximal ureteral calculi. A total of 111 patients (86 male, 25 females M/F: 3.44/1) with impacted proximal ureteral stones treated with shock wave lithotripsy were evaluated. Cases were retrieved from a departmental shock wave lithotripsy database. Variables analyzed included BMI of the case, diameter of proximal ureter and renal pelvis, stone size and Hounsfield unit, ureteral wall thickness at the impacted stone site. Stone-free status on follow-up imaging at 3 months was considered a successful outcome. All patients had a single impacted proximal ureteral stone. While the mean age of the cases was 46 ± 13 years (range 26-79 years), mean stone size was 8.95 mm (5.3-15.1 mm). Following shock wave lithotripsy although 87 patients (78.4%) were completely stone-free at 3-month follow-up visit, 24 (21.6%) cases had residual fragments requiring further repeat procedures. Prediction of the final outcome of SWL in patients with impacted proximal ureteral stones is a challenging issue and our data did clearly indicate a highly significant relationship between ureteral wall thickness and the success rates of shock wave lithotripsy particularly in cases requiring additional procedures. Of all the evaluated stone- and patient-related factors, only ureteral wall thickness at the impacted stone site independently predicted shock wave lithotripsy success. PMID:25417717

  6. Abdominal Compartment Hypertension and Abdominal Compartment Syndrome.

    PubMed

    Maluso, Patrick; Olson, Jody; Sarani, Babak

    2016-04-01

    Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare but potentially morbid diagnoses. Clinical index of suspicion for these disorders should be raised following massive resuscitation, abdominal wall reconstruction/injury, and in those with space-occupying disorders in the abdomen. Gold standard for diagnosis involves measurement of bladder pressure, with a pressure greater than 12 mm Hg being consistent with IAH and greater than 25 mm Hg being consistent with ACS. Decompressive laparotomy is definitive therapy but paracentesis can be equally therapeutic in properly selected patients. Left untreated, ACS can lead to multisystem organ failure and death. PMID:27016163

  7. Thermoelastic Analysis of a Functionally Graded Rotating Thick-Walled Tube Subjected to Mechanical and Thermal Loads

    NASA Astrophysics Data System (ADS)

    Xin, Libiao; Yang, Shengyou; Ma, Baoyu; Dui, Guansuo

    2015-11-01

    A thermoelastic solution for the functionally graded rotating thick-walled tube subjected to axisymmetric mechanical and thermal loads is given in terms of volume fractions of constituents. We assume that the tube consists of two linear elastic constituents and the volume fraction of one phase is a power function varied in the radial direction. By using the assumption of a uniform strain field within the representative volume element, the theoretical solutions of the displacement and the stresses are presented. Based on the relation of the volume average stresses of constituents and the macroscopic stresses of the composite material in micromechanics, the present method can avoid the assumption of the distribution regularities of unknown overall material parameters appeared in existing papers, such as Young's modulus, thermal expansion coefficient, thermal conductivity, and density. The effects of the angular velocity, the volume fraction, the ratio of two thermal expansion coefficients, the ratio of two thermal conductivities, and the ratio of two densities on the displacement and stresses are systematically studied, which should help structural engineers and material scientists optimally design thick-walled tube comprised inhomogeneous materials.

  8. Instrumented thick-walled tube method for measuring thermal pressure in fluids and isotropic stresses in thermosetting resins

    NASA Astrophysics Data System (ADS)

    Merzlyakov, Mikhail; Simon, Sindee L.; McKenna, Gregory B.

    2005-06-01

    We have developed a method for measuring the thermal pressure coefficient and cure-induced and thermally induced stresses based on an instrumented thick-walled tube vessel. The device has been demonstrated at pressures up to 330 MPa and temperatures to 300 °C. The method uses a sealed stainless steel thick-walled tube to impose three-dimensional isotropic constraints. The tube is instrumented with strain gauges in hoop and in axial directions and can be used in open or closed configurations. By making measurements of the isotropic stresses as a function of temperature, the method allows determination of the thermal pressure coefficient in both the glassy and rubbery (or liquid) states. The method also can be used to measure isotropic stress development in thermosetting resins during cure and subsequent thermal cycling. Experimental results are presented for sucrose benzoate, di-2-ethylhexylsebacate, and an epoxy resin. The current report shows that the method provides reliable estimates for the thermal pressure coefficient. The thermal pressure coefficient is determined with resolution on the order of 10kPa/K. Among advantages of the method is that the tubes are reusable, even when measurements are made for cure response of thermosetting resins.

  9. Does reduced myocardial efficiency in systemic hypertensive-hypertrophy correlate with increased left-ventricular wall thickness?

    PubMed

    Han, June-Chiew; Barrett, Carolyn J; Taberner, Andrew J; Loiselle, Denis S

    2015-08-01

    Elevated systemic blood pressure, and the attendant development of pathologic left ventricular (LV) hypertrophy, ultimately culminates in heart failure and death. In clinical studies, a reduction of myocardial efficiency has been implicated in systemic hypertensive-hypertrophy. However, it is uncertain whether reduced efficiency correlates with LV wall thickness. Hence, we performed experiments on isolated working hearts of spontaneously hypertensive rats (SHRs)-a widely-used experimental model of human hypertensive-hypertrophy. We contrasted their mechanoenergetic performance with that of Wistar controls at two ages: Adult (9 months) and Aged (post-18 months). The use of animal hearts allowed us to perform experiments over a wide range of afterloads. We found that mechanoenergetic performance (coronary and aortic flows, work output and oxygen consumption) declined with age. The peak efficiency of the Adult SHR was essentially similar to that of Control, but that for the Aged SHR was lower, compared with that of age-matched Wistar rats. All variables, including peak efficiency, obtained from the failing Aged SHR hearts (which also developed right ventricular hypertrophy), were greatly reduced. Our data reveal that peak efficiency of the Aged SHR, upon transitioning from compensated hypertrophy to failure, diminishes sharply, arising from compromised flows-both aortic and coronary. We further show that the reduction of myocardial efficiency in hypertensive-hypertrophy does not correlate with LV wall thickness, but instead is inversely correlated with whole-heart mass. The latter relation may serve as a prognostic and diagnostic tool in the clinical setting. PMID:25787044

  10. Thick growing multilayer nanobrick wall thin films: super gas barrier with very few layers.

    PubMed

    Guin, Tyler; Krecker, Michelle; Hagen, David Austin; Grunlan, Jaime C

    2014-06-24

    Recent work with multilayer nanocoatings composed of polyelectrolytes and clay has demonstrated the ability to prepare super gas barrier layers from water that rival inorganic CVD-based films (e.g., SiOx). In an effort to reduce the number of layers required to achieve a very low oxygen transmission rate (OTR (<0.01 cc/m(2)·day·atm)) in these nanocoatings, buffered cationic chitosan (CH) and vermiculite clay (VMT) were deposited using layer-by-layer (LbL) assembly. Buffering the chitosan solution and its rinse with 50 mM Trizma base increased the thickness of these films by an order of magnitude. The OTR of a 1.6-μm-thick, six-bilayer film was 0.009 cc/m(2)·day·atm, making this the best gas barrier reported for such a small number of layers. This simple modification to the LbL process could likely be applied more universally to produce films with the desired properties much more quickly. PMID:24914613

  11. SU-C-BRA-04: Use of Esophageal Wall Thickness in Evaluation of the Response to Chemoradiation Therapy for Esophageal Cancer

    SciTech Connect

    Wang, J; Kligerman, S; Lu, W; Kang, M

    2015-06-15

    Purpose: To quantitatively evaluate the esophageal cancer response to chemoradiation therapy (CRT) by measuring the esophageal wall thickness in CT. Method: Two datasets were used in this study. The first dataset is composed of CT scans of 15 esophageal cancer patients and 15 normal controls. The second dataset is composed of 20 esophageal cancer patients who underwent PET/CT scans before (Pre-CRT) and after CRT (Post-CRT). We first segmented the esophagus using a multi-atlas-based algorithm. The esophageal wall thickness was then computed, on each slice, as the equivalent circle radius of the segmented esophagus excluding the lumen. To evaluate the changes of wall thickness, we computed the standard deviation (SD), coefficient of variation (COV, SD/Mean), and flatness [(Max–Min)/Mean] of wall thickness along the entire esophagus. Results: For the first dataset, the mean wall thickness of cancer patients and normal controls were 6.35 mm and 6.03 mm, respectively. The mean SD, COV, and flatness of the wall thickness were 2.59, 0.21, and 1.27 for the cancer patients and 1.99, 0.16, and 1.13 for normal controls. Statistically significant differences (p < 0.05) were identified in SD and flatness. For the second dataset, the mean wall thickness of pre-CRT and post-CRT patients was 7.13 mm and 6.84 mm, respectively. The mean SD, COV, and flatness were 1.81, 0.26, and 1.06 for pre-CRT and 1.69, 0.26, and 1.06 for post-CRT. Statistically significant difference was not identified for these measurements. Current results are based on the entire esophagus. We believe significant differences between pre- and post-CRT scans could be obtained, if we conduct the measurements at tumor sites. Conclusion: Results show thicker wall thickness in pre-CRT scans and differences in wall thickness changes between normal and abnormal esophagus. This demonstrated the potential of esophageal wall thickness as a marker in the tumor CRT response evaluation. This work was supported in part by the National Cancer Institute Grant R01CA172638.

  12. Effect of internal defects in steel on the quality of welded thick-walled equipment

    SciTech Connect

    Polikarpov, M.I.; Kirilenko, E.I.; Lamzin, A.G.; Markov, S.G.; Medinskaya, I.P.; Sukharev, L.G.

    1983-09-01

    The ultrasonic inspection of sheet steel showed the presence of internal defects whose origins were believed to be caused by the failure of the linear nonmetallic inclusions or of the boundaries between the inclusions and the metal with the formation of porosity. Tests were conducted with sulphur prints to determine the level of metal contamination with nonmetallic inclusions, and chemical nonhomgenity was discovered. It was concluded that the significant level of metal contamination with nonmetallic inclusions and the consequent low capability to deform in the thickness direction resulted in the formation of defects like stepped cracks and concentration cracks during the manufacture of the shells. Two methods to correct and repair the shells are introduced: deposition of metal by manual arc welding to fill the defective zones removed earlier, and replacement of a part of the shell or sheet. This technology ensures repairs of high quality.

  13. Displacements and strains in thick-walled composite rings subjected to external pressure using moire interferometry

    NASA Astrophysics Data System (ADS)

    Gascoigne, Harold E.; Abdallah, Mohamed G.

    1991-12-01

    Through the utilization of moire interferometry, in-plane displacements and strains are determined in the radial cross-section of a laminated graphite-epoxy ring subjected to external hydrostatic pressure containing isolated wrinkled (wavy) ply regions. Wrinkled plies arising during manufacturing often occur in thick cylindrical composite sections and their presence raises questions as to their influence on structural integrity. The determination of strains in these anomalous wavy regions will provide valuable information by which these questions will be answered. A specially developed test apparatus which produces the external pressure loading on ring specimens is described. Displacements and strains are presented for two regions of a laminated, cross-ply graphite-epoxy ring--one region is relatively free of wrinkles while the other region contains an isolated, approximately symmetrical group of wavy plies. The marked effect of wavy plies on the distribution of strain in this ring is clearly demonstrated.

  14. In a dynamic lifting task, the relationship between cross-sectional abdominal muscle thickness and the corresponding muscle activity is affected by the combined use of a weightlifting belt and the Valsalva maneuver.

    PubMed

    Blanchard, Trevor W; Smith, Camille; Grenier, Sylvain G

    2016-06-01

    It has been shown that under isometric conditions, as the activity of the abdominal muscles increases, the thicknesses of the muscles also increase. The purpose of this experiment was to determine whether change in muscle thickness could be used as a measure of muscle activity during a deadlift as well as determining the effect of a weightlifting belt and/or the Valsalva maneuver on the muscle thicknesses. The Transversus Abdominis (TrA) and Internal Obliques (IO) muscles were analyzed at rest and during a deadlift. Muscle thickness was measured using ultrasound imaging and muscle activity was simultaneously recorded using electromyography. Each subject performed deadlift under normal conditions, while performing the Valsalva maneuver, while wearing a weightlifting belt and while both utilizing the belt and the Valsalva maneuver. There was no relationship between change in muscle thickness and muscle activity for both the TrA and IO (R(2)<0.13 for all conditions). However it was found that the Valsalva maneuver increased abdominal muscle thickness whereas the belt limited muscle expansion; each with an increase in activity. These results indicate that ultrasound cannot be used to measure muscle activity for a deadlift and that the belt affects how the IO and TrA function together. PMID:27093137

  15. The impact of transcatheter aortic valve implantation on left ventricular performance and wall thickness – single-centre experience

    PubMed Central

    Szymański, Piotr; Dąbrowski, Maciej; Zakrzewski, Dariusz; Michałek, Piotr; Orłowska-Baranowska, Ewa; El-Hassan, Kamal; Chmielak, Zbigniew; Witkowski, Adam; Hryniewiecki, Tomasz

    2015-01-01

    Introduction Transcatheter aortic valve implantation (TAVI) is a treatment alternative for the elderly population with severe symptomatic aortic stenosis (AS) at high risk for surgical aortic valve replacement (SAVR). Aim To assess the impact of TAVI on echocardiographic parameters of left ventricular (LV) performance and wall thickness in patients subjected to the procedure in a single-centre between 2009 and 2013. Material and methods The initial group consisted of 170 consecutive patients with severe AS unsuitable for SAVR. Logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 21.73 ±12.42% and mean age was 79.9 ±7.5 years. Results The TAVI was performed in 167 (98.2%) patients. Mean aortic gradient decreased significantly more rapidly after the procedure (from 58.6 ±16.7 mm Hg to 11.9 ±4.9 mm Hg, p < 0.001). The LV ejection fraction (LVEF) significantly increased in both short-term and long-term follow-up (57 ±14% vs. 59 ±13%, p < 0.001 and 56 ±14% vs. 60 ±12%, p < 0.001, respectively). Significant regression of interventricular septum diameter at end-diastole (IVSDD) and end-diastolic posterior wall thickness (EDPWth) was noted in early (15.0 ±2.4 mm vs. 14.5 ±2.3 mm, p < 0.001 and 12.7 ±2.1 mm vs. 12.4 ±1.9 mm, p < 0.028, respectively) and late post-TAVI period (15.1 ±2.5 mm to 14.3 ±2.5 mm, p < 0.001 and 12.8 ±2.0 mm to 12.4 ±1.9 mm, p < 0.007, respectively). Significant paravalvular leak (PL) was noted in 21 (13.1%) patients immediately after TAVI and in 13 (9.6%) patients in follow-up (p < 0.001). Moderate or severe mitral regurgitation (msMR) was seen in 24 (14.9%) patients from the initial group and in 19 (11.8%) patients after TAVI (p < 0.001). Conclusions The TAVI had an immediate beneficial effect on LVEF, LV walls thickness, and the incidence of msMR. The results of the procedure are comparable with those described in other centres. PMID:25848369

  16. Environmentally-controlled fracture of an overstrained A723 steel thick-walled cylinder

    NASA Astrophysics Data System (ADS)

    Underwood, J. H.; Olmstead, V. J.; Askew, J. C.; Kapusta, A. A.; Young, G. A.

    1992-08-01

    A through-wall, 1.7 m long crack grew suddenly from a notch in a 285 mm outer diameter (OD) of an A723 steel overstrained tube that was undergoing plating operations with no externally applied loads. The fracture mechanics tests and analyses and the fractography performed to characterize the cracking are described. The tube had a yield strength of 1200 MPa, fracture toughness of 150 MPavm, and a tensile residual stress at the OD of about 600 MPa. The composition was typical of an air-melt A723 steel, and the electropolishing bath, consisting of sulfuric and phosphoric acids, was held at 54 C. The bolt-loaded test for the threshold stress intensity factor for environmentally controlled cracking described by Wei and Novak was used here with two significant modifications. Some tests included only a notch with the radius matching that of the tube, and a new expression for K in terms of crack-mouth displacement was developed and used. Scanning electron microscope fractography and energy dispersive x ray spectra were used to identify crack mechanisms. Results of the study include: (1) a measured threshold of hydrogen stress cracking for the material/environment below 20 MPavm; (2) da/dt versus K behavior typical of classic environmental control; and (3) an improved K/v expression for the bolt-loaded specimen and associated criteria for determining plane-strain test conditions in relation to the Irwin plastic zone.

  17. Abdominal pain

    MedlinePlus

    Stomach pain; Pain - abdomen; Belly ache; Abdominal cramps; Bellyache; Stomachache ... bad abdominal pain if you have gas or stomach cramps due to viral gastroenteritis . However, life-threatening ...

  18. Quantum confinement effect in Bi anti-dot thin films with tailored pore wall widths and thicknesses

    SciTech Connect

    Park, Y.; Hirose, Y.; Fukumura, T.; Hasegawa, T.; Nakao, S.; Xu, J.

    2014-01-13

    We investigated quantum confinement effects in Bi anti-dot thin films grown on anodized aluminium oxide templates. The pore wall widths (w{sub Bi}) and thickness (t) of the films were tailored to have values longer or shorter than Fermi wavelength of Bi (λ{sub F} = ∼40 nm). Magnetoresistance measurements revealed a well-defined weak antilocalization effect below 10 K. Coherence lengths (L{sub ϕ}) as functions of temperature were derived from the magnetoresistance vs field curves by assuming the Hikami-Larkin-Nagaoka model. The anti-dot thin film with w{sub Bi} and t smaller than λ{sub F} showed low dimensional electronic behavior at low temperatures where L{sub ϕ}(T) exceed w{sub Bi} or t.

  19. Uncertainty induced by chest wall thickness assessment methods on lung activity estimation for plutonium and americium: a large population-based study.

    PubMed

    Broggio, D; Lechaftois, X; Franck, D

    2015-03-01

    In vivo lung counting aims at assessing the retained activity in the lungs. The calibration factor relating the measured counts to the worker's specific retained lung activity can be obtained by several means and strongly depends on the chest wall thickness. Here we compare, for 374 male nuclear workers, the activity assessed with a reference protocol, where the material equivalent chest wall thickness is known from ultrasound measurements, with two other protocols. The counting system is an array of four germanium detectors.It is found that non site-specific equations for the assessment of the chest wall thickness induce large biases in the assessment of activity. For plutonium isotopes or (241)Am the proportion of workers for whom the retained activity is within ± 10% of the reference one is smaller than 10%.The use of site-specific equations raises this proportion to 20% and 58% for plutonium and (241)Am, respectively.Finally, for the studied population, when site-specific equations are used for the chest wall thickness, the standard uncertainties for the lung activity are 42% and 12.5%, for plutonium and (241)Am, respectively. Due to the relatively large size of the studied population, these values are a relatively robust estimate of the uncertainties due to the assessment of the chest wall thickness for the current practice at this site. PMID:25517347

  20. The heart's fibre alignment assessed by comparing two digitizing systems. Methodological investigation into the inclination angle towards wall thickness.

    PubMed

    Lunkenheimer, P P; Redmann, K; Dietl, K H; Cryer, C; Richter, K D; Whimster, W F; Niederer, P

    1997-04-01

    Myocardial contractile pathways which are not aligned strictly parallel to the heart's epicardial surface, give rise to forces which also act in the ventricular dilating direction. We developed a method which allows us to assess any fibre orientation in the three-dimensional myocardial weave. Decollagenized hearts were prepared by peeling-off fibre strands, following their main fibre orientation down to near the endocardium. In the subepicardium the strands followed a course more or less parallel to the epicardium, whereas from the mid-wall on they tended to dive progressively deeper into the wall. The preparation displays more or less rugged surfaces rather than smooth layers. The grooves and crests on the exposed surfaces were sequentially digitized by two methods: (1) Using a magnet tablet (3 Draw Digitizer System, Polhemus, Cochester VTO 5446, USA) on a dilated pig heart we manually followed the crests using a stylus, handling each groove and crest as an individual contractile pathway. (2) A constricted cow heart was digitized using a contact-free optical system (opto TOP, Dr. Breuckmann, Meersburg, Germany), which is based on the principle of imaging triangulation. Using specially developed software the inclination angles of selected crests and grooves with respect to the epicardial surface were calculated. The two digitizing methods yield comparable results. We found a depth- and side-specific weave component inclined to the epi-endocardial direction. This oblique netting component was more pronounced in the inner 1/3 of the wall than in the subepicardium. The inclination angle probably increases with increasing wall thickness during the ejection period. Manual digitizing is an easy and fast method which delivers consistent results comparable with those obtained by the cumbersome high resolution optical method. The rationales for the assessment of transmural fibre inclination are (1) the putative existence of dilating forces inherent in the myocardial weave and (2) the possible overproportional increase in the oblique transmural weave component during myocardial hypertrophy, which would entail a reduction in efficiency of ventricular performance in terms of haemodynamic work. PMID:9134620

  1. Increased airway reactivity in human RSV bronchiolitis in the guinea pig is not due to increased wall thickness.

    PubMed

    Robinson, P J; Hegele, R G; Schellenberg, R R

    1996-10-01

    Bronchiolitis due to the respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection in the first year of life. It has been suggested that RSV infection may cause subsequent asthma, but a mechanism for this relationship has not been demonstrated. Studies examining the presence of airway reactivity in infants with RSV bronchiolitis are limited by our inability to administer provocative agents such as histamine to such ill infants. This makes a small animal model of this condition a useful tool in which to investigate the pathophysiology of RSV bronchiolitis. We, therefore, evaluated airway responsiveness in vivo and airway morphometric changes in 20 guinea pigs infected by instilling 4,000 plaque-forming units of human RSV virus onto the nasal mucosa under halothane anaesthesia, while 20 control animals received an equivalent volume of sterile cell culture medium. Six days following instillation, 10 infected animals and 10 controls underwent measurements of pulmonary resistance (RL) following increasing doses of inhaled acetylcholine (Ach). These guinea pigs were then sacrificed and the lung and heart removed en bloc for morphometric studies. There were no differences in baseline RL between infected and control groups. At Ach concentrations of 15 and 50 mg/mL, RSV-infected animals had higher RL values than controls (P < 0.05). Fourteen days following RSV instillation no differences in Ach responses were detected in the 10 infected and 10 control animals studied. To determine whether the increase in airway reactivity 6 days after RSV instillation was associated with changes in airway wall morphometry, 125 airways (69 infected, 56 control) were studied. Analysis of wall area, wall area internal to the smooth muscle, or smooth muscle area standardized by the internal perimeter of the airway showed no significant differences between the infected and control airways. These results demonstrated that airway hyperresponsiveness correlated with previously reported histologic changes of acute bronchiolitis 6 days after guinea pigs were infected with human RSV, but neither hyperresponsiveness nor histological changes persisted following resolution of the primary infection. The increased airway reactivity and the previously observed histological changes seen at day 6 following infection was not due to increased airway wall thickness. PMID:8905885

  2. Recurrent incisional hernia, enterocutaneous fistula and loss of the substance of the abdominal wall: plastic with organic prosthesis, skin graft and VAC therapy. Clinical case.

    PubMed

    Nicodemi, Sara; Corelli, Sergio; Sacchi, Marco; Ricciardi, Edoardo; Costantino, Annarita; Di Legge, Pietro; Ceci, Francesco; Cipriani, Benedetta; Martellucci, Annunziata; Santilli, Mario; Orsini, Silvia; Tudisco, Antonella; Stagnitti, Franco

    2015-01-01

    Surgical wounds dehiscence is a serious post-operatory complication, with an incidence between 0.4% and 3.5%. Mortality is more than 45%. Complex wounds treatment may require a multidisciplinary management. VAC Therapy could be an alternative treatment regarding complex wound. VAC therapy has been recently introduced on skin's graft tissue management reducing skin graft rejection. The use of biological prosthesis has been tested in a contaminated field, better than synthetic meshes, which often need to be removed. The Permacol is more resistant to degradation by proteases due to its cross-links. Surgery is still considered the best treatment for digestive fistula. A 58 years old obese woman come to our attention, she was operated for an abdominal hernia. She had a post-operatory entero-cutaneous fistula. She was submitted to bowel resection, the anastomosis has been tailored and the hernia of the abdominal wall has been repaired with biological mesh for managing such condition. She had a wound dehiscence with loss of substance and the exposure of the biological prosthesis, nearly 20 cm diameter. She was treated first with antibiotic therapy and simple medications. In addiction, antibiotic therapy was necessary late associated to 7 months with advanced medications allowed a small reduction's defect. Because of its, treatment went on for two more months using VAC therapy. Antibiotic's therapy was finally suspended. The VAC therapy allowed the reduction of the gap, between skin and subcutaneous tissue, and the defect's size preparing a suitable ground for the skin graft. The graft, managed with the vac therapy, was necessary to complete the healing process. PMID:25953007

  3. Open repair of large abdominal wall hernias with and without components separation; an analysis from the ACS-NSQIP database

    PubMed Central

    Desai, Nirav K.; Leitman, I. Michael; Mills, Christopher; Lavarias, Valentina; Lucido, David L.; Karpeh, Martin S.

    2016-01-01

    Background Components separation technique emerged several years ago as a novel procedure to improve durability of repair for ventral abdominal hernias. Almost twenty-five years since its initial description, little comprehensive risk adjusted data exists on the morbidity of this procedure. This study is the largest analysis to date of short-term outcomes for these cases. Methods The ACS-NSQIP database identified open ventral or incisional hernia repairs with components separation from 2005 to 2012. A data set of cohorts without this technique, matched for preoperative risk factors and operative characteristics, was developed for comparison. A comprehensive risk-adjusted analysis of outcomes and morbidity was performed. Results A total of 68,439 patients underwent open ventral hernia repair during the study period (2245 with components separation performed (3.3%) and 66,194 without). In comparison with risk-adjusted controls, use of components separation increased operative duration (additional 83 min), length of stay (6.4 days vs. 3.8 days, p < 0.001), return to the OR rate (5.9% vs. 3.6%, p < 0.001), and 30-day morbidity (10.1% vs. 7.6%, p < 0.001) with no increase in mortality (0.0% in each group). Conclusions Components separation technique for large incisional hernias significantly increases length of stay and postoperative morbidity. Novel strategies to improve short-term outcomes are needed with continued use of this technique. PMID:27158489

  4. It is Highly Unlikely that the Development of an Abdominal Wall Hernia can be Attributable to a Single Strenuous Event

    PubMed Central

    Samir, Pathak; Poston, Graeme J

    2006-01-01

    INTRODUCTION There is a commonly held belief that the development of a hernia can be attributed to a single strenuous or traumatic event. Hence, many litigants are successful in compensation claims, causing mounting financial burdens on employers, the courts, insurance companies and the tax-payer. However, there is very little scientific evidence to support this assertion. The aim of this study was to ascertain whether there was any causal link in this process. PATIENTS AND METHODS A total of 133 new patients with 135 abdominal herniae of all varieties (115 inguinal, 3 femoral, 9 umbilical, 4 incisional, and 4 ventral or epigastric), of which 25 were recurrent received structured questionnaires on arrival in the surgical clinic. These questionnaires covered all possible aetiological factors for hernia development (type of work, COAD, smoking, pregnancy, obesity, chronic bladder outflow obstruction, previous surgery including appendicectomy), in addition to any possible attribution to a single strenuous or traumatic event. We then reviewed the GP records in the surgery of all patients who answered positively to the latter possible cause. RESULTS In the study group, 119 (89%) reported a gradual onset of symptoms. Of the 15 (12 male, 3 female; 11%) who believed that their hernia might be related to a single strenuous or traumatic event, 5 had no other aetiological factors. However, not one of the 15 was found to have contemporaneous forensic medical evidence to support their possible claim. CONCLUSIONS We conclude that we are unable to find any clinical evidence to support the hypothesis that a hernia might develop as the result of one single strenuous or traumatic event. While we accept that this mechanism might still possibly occur, we believe that, at best, it is extremely uncommon. If a medical expert is preparing a report on such a case in a claim for personal injury, then they have a duty to the court to examine carefully all the contemporaneous medical records. If no clinical evidence exists to support the claim, then they have a duty to the court not to support the plaintiff's claim. PMID:16551411

  5. 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-constructive remodeling of an abdominal wall repair site with synthetic mesh reinforcement is most likely to occur. PMID:24442681

  6. Analysis of the Effect of Osteon Diameter on the Potential Relationship of Osteocyte Lacuna Density and Osteon Wall Thickness

    PubMed Central

    Skedros, John G.; Clark, Gunnar C.; Sorenson, Scott M.; Taylor, Kevin W.; Qiu, Shijing

    2011-01-01

    An important hypothesis is that the degree of infilling of secondary osteons (Haversian systems) is controlled by the inhibitory effect of osteocytes on osteoblasts, which might be mediated by sclerostin (a glycoprotein produced by osteocytes). Consequently, this inhibition could be proportional to cell number: relatively greater repression is exerted by progressively greater osteocyte density (increased osteocytes correlate with thinner osteon walls). This hypothesis has been examined, but only weakly supported, in sheep ulnae. We looked for this inverse relationship between osteon wall thickness (On.W.Th) and osteocyte lacuna density (Ot.Lc.N/B.Ar) in small and large osteons in human ribs, calcanei of sheep, deer, elk, and horses, and radii and third metacarpals of horses. Analyses involved: (1) all osteons, (2) smaller osteons, either ≤150μm diameter or ≤ the mean diameter, and (3) larger osteons (>mean diameter). Significant, but weak, correlations between Ot.Lc.N/B.Ar and On.W.Th/On.Dm (On.Dm = osteon diameter) were found when considering all osteons in limb bones (r values −0.16 to −0.40, p<0.01; resembling previous results in sheep ulnae: r= −0.39, p<0.0001). In larger osteons, these relationships were either not significant (five/seven bone types) or very weak (two/seven bone types). In ribs, a negative relationship was only found in smaller osteons (r= −0.228, p<0.01); this inverse relationship in smaller osteons did not occur in elk calcanei. These results do not provide clear or consistent support for the hypothesized inverse relationship. However, correlation analyses may fail to detect osteocyte-based repression of infilling if the signal is spatially non-uniform (e.g., increased near the central canal). PMID:21809466

  7. Left ventricular wall thickness in patients with hypertrophic cardiomyopathy: a comparison between cardiac magnetic resonance imaging and echocardiography.

    PubMed

    Corona-Villalobos, Celia P; Sorensen, Lars L; Pozios, Iraklis; Chu, Linda; Eng, John; Abraham, Maria Roselle; Abraham, Theodore P; Kamel, Ihab R; Zimmerman, Stefan L

    2016-06-01

    We assessed whether cardiac MRI (CMR) and echocardiography (echo) have significant differences measuring left ventricular (LV) wall thickness (WT) in hypertrophic cardiomyopathy (HCM) as performed in the clinical routine. Retrospectively identified, clinically diagnosed HCM patients with interventricular-septal (IVS) pattern hypertrophy who underwent CMR and echo within the same day were included. Left Ventricular WT was measured by CMR in two planes and compared to both echo and contrast echo (cecho). 72 subjects, mean age 50.7 ± 16.2 years, 68 % males. Interventricular septal WT by echo and CMR planes showed good to excellent correlation. However, measurements of the postero-lateral wall showed poor correlation. Bland-Altman plots showed greater maximal IVS WT by echo compared to CMR measurement [SAX = 1.7 mm (-5.8, 9.3); LVOT = 1.1 mm (-5.6, 7.8)]. Differences were smaller between cecho and CMR [SAX = 0.8 mm (-9.2, 10.8); LVOT = -0.2 mm (-10.0, 9.6)]. Severity of WT by quartiles showed greater differences between echo and SAX CMR WT compared to cecho. Echocardiography typically measures greater WT than CMR, with the largest differences in moderate to severe hypertrophy. Contrast echocardiography more closely approximates CMR measurements of WT. These findings have potential clinical implications for risk stratification of subjects with HCM. PMID:26896038

  8. Welding for testability: An approach aimed at improving the ultrasonic testing of thick-walled austenitic and dissimilar metal welds

    NASA Astrophysics Data System (ADS)

    Wagner, Sabine; Dugan, Sandra; Barth, Martin; Schubert, Frank; Köhler, Bernd

    2014-02-01

    Austenitic and dissimilar welds in thick walled components show a coarse grained, dendritic microstructure. Therefore, ultrasonic testing has to deal with beam refraction, scattering and mode conversion effects. As a result, the testing techniques typically applied for isotropic materials yield dissatisfying results. Most approaches for improvement of ultrasonic testing have been based on modeling and improved knowledge of the complex wave propagation phenomena. In this paper, we discuss an alternative approach: is it possible to use a modified welding technology which eliminates the cause of the UT complications, i.e. the large-grained structure of the weld seams? Various modification parameters were tested, including: TIG current pulsing, additional DC and AC magnetic fields, and also additional external vibrations during welding. For all welds produced under different conditions, the grain structure of the weld seam was characterized by optical and GIUM microstructure visualizations on cross sections, wave field propagation measurements, and ultrasonic tests of correct detectability of flaws. The mechanical properties of the welds were also tested.

  9. Welding for testability: An approach aimed at improving the ultrasonic testing of thick-walled austenitic and dissimilar metal welds

    SciTech Connect

    Wagner, Sabine; Dugan, Sandra; Barth, Martin; Schubert, Frank; Köhler, Bernd

    2014-02-18

    Austenitic and dissimilar welds in thick walled components show a coarse grained, dendritic microstructure. Therefore, ultrasonic testing has to deal with beam refraction, scattering and mode conversion effects. As a result, the testing techniques typically applied for isotropic materials yield dissatisfying results. Most approaches for improvement of ultrasonic testing have been based on modeling and improved knowledge of the complex wave propagation phenomena. In this paper, we discuss an alternative approach: is it possible to use a modified welding technology which eliminates the cause of the UT complications, i.e. the large-grained structure of the weld seams? Various modification parameters were tested, including: TIG current pulsing, additional DC and AC magnetic fields, and also additional external vibrations during welding. For all welds produced under different conditions, the grain structure of the weld seam was characterized by optical and GIUM microstructure visualizations on cross sections, wave field propagation measurements, and ultrasonic tests of correct detectability of flaws. The mechanical properties of the welds were also tested.

  10. Mechanical Performance and Failure Mechanism of Thick-walled Composite Connecting Rods Fabricated by Resin Transfer Molding Technique

    NASA Astrophysics Data System (ADS)

    Liu, Gang; Luo, Chuyang; Zhang, Daijun; Li, Xueqin; Qu, Peng; Sun, Xiaochen; Jia, Yuxi; Yi, Xiaosu

    2015-08-01

    A resin transfer molding technique was used to fabricate thick-walled composite connecting rods, and then the mechanical performance of the connecting rod was studied experimentally, at the same time the stress and failure index distributions were simulated numerically. The experimental results show that under a tensile load, the connecting rod first cracks near the vertex of the triangle areas at the two ends, and then the damage propagates along the interface between the main bearing beam and the triangle area as well as along the round angle of the triangle area. Whereas under a compressive load, the delamination primarily occurs at the corner of the U-shaped flange, and the final destruction is caused by the fracture of fibers in the main bearing beam. The simulated results reveal that the tensile failure is originated from the delamination at the round angle transition areas of the T-joints, and the failure strength is determined by the interlaminar strength. Whereas the compressive failure is caused by the fracture of fibers in the main bearing beam, and the failure strength of the structure is determined by the longitudinal compressive strength of the composite material. The simulated results are basically consistent with the experimental results. Hence the mechanical performance and failure mechanism of the complicated composite structure are revealed in great detail through the coupling of the two kinds of research methods, which is helpful for the optimal design of composite structures.

  11. Failure Analysis of Weld Cracking in a Thick-Walled 2.25Cr-1Mo Steel Pressure Vessel

    NASA Astrophysics Data System (ADS)

    Lei, Xiaowei; Niu, Jing; Zhang, Jianxun; Fu, Anqing; Feng, Yaorong

    2014-04-01

    A crack in thick-walled 2.25Cr-1Mo steel pressure vessel girth weld was found during manufacturing. To investigate the cause of failure, optical microscopy, scanning electron microscopy, energy dispersive spectrometer, transmission electron microscopy, and microhardness tester were used in this study. According to test results, the fracture is classified as reheat cracking with multiple origins. The cracking occurred during surfacing or final post-weld heat treatment process. Coarse-grains in the weld and bulk-carbides precipitated along grain boundaries induced by multiple heating are main causes of the fracture from material aspect, while high level of the hoop stress component and excess localized deformation in stress relief procedure are mechanical aspect causes of the cracking. The fracture surfaces present major intergranular feature with a small fraction of transgranular morphologies. Large numbers of M3C and M23C6 carbides particles were found on the fracture surface, these carbides mainly precipitated on prior austenite-grain boundaries, columnar-grain boundaries, and sub-grain boundaries. Additionally, several proposals were also offered to reduce weld cracking of 2.25Cr-1Mo steel pressure vessels.

  12. A tale of two neglected systems—structure and function of the thin- and thick-walled sieve tubes in monocotyledonous leaves

    PubMed Central

    Botha, C. E. J.

    2013-01-01

    There is a large body of information relating to the ontogeny, development and the vasculature of eudicotyledonous leaves. However, there is less information available concerning the vascular anatomy of monocotyledonous leaves. This is surprising, given that there are two uniquely different phloem systems present in large groups such as grasses and sedges. Monocotyledonous leaves contain marginal, large, intermediate, and small longitudinal veins that are interconnected by numerous transverse veins. The longitudinal veins contain two metaphloem sieve tube types, which, based upon their ontogeny and position within the phloem, are termed early (thin-walled) and late (thick-walled) sieve tubes. Early metaphloem comprises sieve tubes, companion cells and vascular parenchyma (VP) cells, whilst the late metaphloem, contains thick-walled sieve tubes (TSTs) that lack companion cells. TSTs are generally adjacent to, or no more than one cell removed from the metaxylem. Unlike thin-walled sieve tube (ST) -companion cell complexes, TSTs are connected to parenchyma by pore-plasmodesma units and are generally symplasmically isolated from the STs. This paper addresses key structural and functional differences between thin- and thick-walled sieve tubes and explores the unique advantages of alternate transport strategies that this 5–7 million years old dual system may offer. It would seem that these two systems may enhance, add to, or play a significant role in increasing the efficiency of solute retrieval as well as of assimilate transfer. PMID:23964280

  13. Human coronary plaque wall thickness correlated positively with flow shear stress and negatively with plaque wall stress: an IVUS-based fluid-structure interaction multi-patient study

    PubMed Central

    2014-01-01

    Background Atherosclerotic plaque progression and rupture are believed to be associated with mechanical stress conditions. In this paper, patient-specific in vivo intravascular ultrasound (IVUS) coronary plaque image data were used to construct computational models with fluid-structure interaction (FSI) and cyclic bending to investigate correlations between plaque wall thickness and both flow shear stress and plaque wall stress conditions. Methods IVUS data were acquired from 10 patients after voluntary informed consent. The X-ray angiogram was obtained prior to the pullback of the IVUS catheter to determine the location of the coronary artery stenosis, vessel curvature and cardiac motion. Cyclic bending was specified in the model representing the effect by heart contraction. 3D anisotropic FSI models were constructed and solved to obtain flow shear stress (FSS) and plaque wall stress (PWS) values. FSS and PWS values were obtained for statistical analysis. Correlations with p < 0.05 were deemed significant. Results Nine out of the 10 patients showed positive correlation between wall thickness and flow shear stress. The mean Pearson correlation r-value was 0.278 ± 0.181. Similarly, 9 out of the 10 patients showed negative correlation between wall thickness and plaque wall stress. The mean Pearson correlation r-value was -0.530 ± 0.210. Conclusion Our results showed that plaque vessel wall thickness correlated positively with FSS and negatively with PWS. The patient-specific IVUS-based modeling approach has the potential to be used to investigate and identify possible mechanisms governing plaque progression and rupture and assist in diagnosis and intervention procedures. This represents a new direction of research. Further investigations using more patient follow-up data are warranted. PMID:24669780

  14. Influence of radiation dose and reconstruction algorithm in MDCT assessment of airway wall thickness: A phantom study

    SciTech Connect

    Gomez-Cardona, Daniel; Nagle, Scott K.; Li, Ke; Chen, Guang-Hong; Robinson, Terry E.

    2015-10-15

    Purpose: Wall thickness (WT) is an airway feature of great interest for the assessment of morphological changes in the lung parenchyma. Multidetector computed tomography (MDCT) has recently been used to evaluate airway WT, but the potential risk of radiation-induced carcinogenesis—particularly in younger patients—might limit a wider use of this imaging method in clinical practice. The recent commercial implementation of the statistical model-based iterative reconstruction (MBIR) algorithm, instead of the conventional filtered back projection (FBP) algorithm, has enabled considerable radiation dose reduction in many other clinical applications of MDCT. The purpose of this work was to study the impact of radiation dose and MBIR in the MDCT assessment of airway WT. Methods: An airway phantom was scanned using a clinical MDCT system (Discovery CT750 HD, GE Healthcare) at 4 kV levels and 5 mAs levels. Both FBP and a commercial implementation of MBIR (Veo{sup TM}, GE Healthcare) were used to reconstruct CT images of the airways. For each kV–mAs combination and each reconstruction algorithm, the contrast-to-noise ratio (CNR) of the airways was measured, and the WT of each airway was measured and compared with the nominal value; the relative bias and the angular standard deviation in the measured WT were calculated. For each airway and reconstruction algorithm, the overall performance of WT quantification across all of the 20 kV–mAs combinations was quantified by the sum of squares (SSQs) of the difference between the measured and nominal WT values. Finally, the particular kV–mAs combination and reconstruction algorithm that minimized radiation dose while still achieving a reference WT quantification accuracy level was chosen as the optimal acquisition and reconstruction settings. Results: The wall thicknesses of seven airways of different sizes were analyzed in the study. Compared with FBP, MBIR improved the CNR of the airways, particularly at low radiation dose levels. For FBP, the relative bias and the angular standard deviation of the measured WT increased steeply with decreasing radiation dose. Except for the smallest airway, MBIR enabled significant reduction in both the relative bias and angular standard deviation of the WT, particularly at low radiation dose levels; the SSQ was reduced by 50%–96% by using MBIR. The optimal reconstruction algorithm was found to be MBIR for the seven airways being assessed, and the combined use of MBIR and optimal kV–mAs selection resulted in a radiation dose reduction of 37%–83% compared with a reference scan protocol with a dose level of 1 mGy. Conclusions: The quantification accuracy of airway WT is strongly influenced by radiation dose and reconstruction algorithm. The MBIR algorithm potentially allows the desired WT quantification accuracy to be achieved with reduced radiation dose, which may enable a wider clinical use of MDCT for the assessment of airway WT, particularly for younger patients who may be more sensitive to exposures with ionizing radiation.

  15. Method and apparatus to produce and maintain a thick, flowing, liquid lithium first wall for toroidal magnetic confinement DT fusion reactors

    DOEpatents

    Woolley, Robert D.

    2002-01-01

    A system for forming a thick flowing liquid metal, in this case lithium, layer on the inside wall of a toroid containing the plasma of a deuterium-tritium fusion reactor. The presence of the liquid metal layer or first wall serves to prevent neutron damage to the walls of the toroid. A poloidal current in the liquid metal layer is oriented so that it flows in the same direction as the current in a series of external magnets used to confine the plasma. This current alignment results in the liquid metal being forced against the wall of the toroid. After the liquid metal exits the toroid it is pumped to a heat extraction and power conversion device prior to being reentering the toroid.

  16. Plastic Response of Tracheids in Pinus pinaster in a Water-Limited Environment: Adjusting Lumen Size instead of Wall Thickness

    PubMed Central

    Carvalho, Ana; Nabais, Cristina; Vieira, Joana; Rossi, Sergio; Campelo, Filipe

    2015-01-01

    The formation of wood results from cambial activity and its anatomical properties reflect the variability of environmental conditions during the growing season. Recently, it was found that wood density variations in conifers growing under cold-limited environment result from the adjustment of cell wall thickness (CWT) to temperature. Additionally, it is known that intra-annual density fluctuations (IADFs) are formed in response to precipitation after the summer drought. Although IADFs are frequent in Mediterranean conifers no study has yet been conducted to determine if these structures result from the adjustment of lumen diameter (LD) or CWT to soil water availability. Our main objective is to investigate the intra-ring variation of wood anatomical features (LD and CWT) in Pinus pinaster Ait. growing under a water-limited environment. We compared the tracheidograms of LD and CWT for the years 2010–2013 in P. pinaster growing in the west coast of Portugal. Our results suggest a close association between LD and soil moisture content along the growing season, reinforcing the role of water availability in determining tracheid size. Compared with CWT, LD showed a higher intra- and inter-annual variability suggesting its strong adjustment value to variations in water availability. The formation of a latewood IADF appears to be predisposed by higher rates of cell production in spring and triggered by early autumn precipitation. Our findings reinforce the crucial role of water availability on cambial activity and wood formation in Mediterranean conifers, and emphasize the high plasticity of wood anatomical features under Mediterranean climate. PMID:26305893

  17. Race and gender differences in the association of Lp(a) with carotid artery wall thickness. The Atherosclerosis Risk in Communities (ARIC) Study.

    PubMed

    Schreiner, P J; Heiss, G; Tyroler, H A; Morrisett, J D; Davis, C E; Smith, R

    1996-03-01

    The association of lipoprotein(a) [Lp(a)] with preclinical atherosclerotic disease is not well established in any race group, particularly African Americans. This report examined the association of Lp(a) with preclinical extracranial carotid atherosclerosis in middle-aged black and white participants in the Atherosclerosis Risk in Communities (ARIC) Study. Study participants (15 124: 2417 black women, 1522 black men, 5907 white women, and 5278 white men) who were 45 to 64 years old at baseline were examined during the period 1987 to 1989. Carotid intimal-medial far-wall thickness was determined by B-mode ultrasonography and expressed as the overall wall thickness mean at six sites to approximate atherosclerosis in the carotid system. Lp(a) was measured as its total protein component, Lp(a) protein, by a double-antibody ELISA for apolipoprotein(a) detection. Mean Lp(a) protein levels were higher in blacks than whites (169.1 and 147.0 microgram/mL in black women and black men, respectively, compared with 86.6 and 75.1 micrograms/mL in white women and white men). Mean carotid wall thickness (in millimeters) varied by race and gender: 0.798 in white men, 0.779 in black men, 0.718 in black women and 0.695 in white women. Multivariable-adjusted Lp(a) protein was independently associated with wall thickness (in millimeters) in white men and black men; among women, however, this association appeared to be stronger when smoking and diabetes were present. A 100-microgram/mL difference in Lp(a) protein was associated with 0.049- and 0.043-mm higher wall thickness values in black men and white men, respectively. Among white women who smoked, the difference in wall thickness was 0.051 mm compared with 0.032 mm for former/never smokers and 0.21 mm in black female diabetics compared with 0.031 mm in black female nondiabetics. These results suggest that Lp(a) is associated with preclinical carotid atherosclerosis in both blacks and whites, but that this association may be affected by the presence of other cardiovascular risk factors, particularly in women. PMID:8630675

  18. Abdominal Assessment.

    PubMed

    Fritz, Deborah; Weilitz, Pamela Becker

    2016-03-01

    Abdominal pain is one of the most common complaints by patients, and assessment of abdominal pain and associated symptoms can be challenging for home healthcare providers. Reasons for abdominal pain are related to inflammation, organ distention, and ischemia. The history and physical examination are important to narrow the source of acute or chronic problems, identify immediate interventions, and when necessary, facilitate emergency department care. PMID:26925941

  19. Relationship between airway wall thickness assessed by high-resolution computed tomography and lung function in patients with asthma and chronic obstructive pulmonary disease.

    PubMed

    Kosciuch, J; Krenke, R; Gorska, K; Zukowska, M; Maskey-Warzechowska, M; Chazan, R

    2009-11-01

    Airway remodeling in asthma and chronic obstructive pulmonary disease (COPD) results in thickening of bronchial walls and may affect lung function. In the present study we set out to evaluate the relationship between small airway wall thickness and the lung function parameters in patients with asthma and COPD. The study was performed in 10 patients with asthma (4M/6F, the mean age 37+/-13 yr) and 12 patients with COPD (7M/5F, the mean age 57+/-9 yr) with stable, mild to moderate disease. The study group characteristics were based on clinical assessment and lung function testing (spirometry, body plethysmography, methacholine challenge test). All patients underwent chest high resolution computerized tomography with small bronchi (external diameter 1-5 mm) cross section measurements at five selected lung levels. The following parameters were measured in end-inspiratory scans: external (D) and internal (L) diameters, wall area (WA), percentage of the wall area (WA%), wall thickness (WT), and WT/D ratio (BWT). We found no significant correlations between airway wall thickness and spirometric parameters in either group. In the asthma group, the relationships between WA% and BWT, on the one side, and postbronchodilator residual volume, on the other, were noted (r=0.72; P<0.05 and r=0.72; P<0.05, respectively). In the COPD group, WA% related with airway resistance (r=0.72; P<0.05). The correlations between WA% and PC(20) (r=-0.61; P<0.05) and BWT and PC(20) (r=-0.72; P<0.05) were found in the COPD group. There was also a relationship between WA% and airway resistance (Raw) (r=0.72; P<0.05) and BWT and Raw (r=0.45; P=0.1). The number of pack-years correlated with WA and WT in COPD patients. In conclusion, the study shows that the thickening of airway wall in asthma is reflected by an increase in the indices of air trapping and in COPD this thickening results in a higher airway resistance and responsiveness. In COPD, the thickening of airway wall also is related to exposure to tobacco smoke. PMID:20134043

  20. As human pial arteries (internal diameter 200-1000 microm) get smaller, their wall thickness and capacity to develop tension relative to their diameter increase.

    PubMed

    Bevan, J A; Dodge, J; Walters, C L; Wellman, T; Bevan, R D

    1999-01-01

    Pial arteries play a key role in the regulation of human cerebral blood flow. However, many of the features and mechanisms that regulate the tone and diameters of these vessels cannot be studied in situ. One approach is to study in vitro segments of arteries obtained during neurosurgical procedures. The ratios of arterial media thickness to lumen diameter and of the capacity to develop wall force to lumen diameter have important functional consequences and are known to change in disease. Experiments were carried out on pial arteries from normotensive humans to determine the way in which these parameters vary with vessel size. Vessel dimensions--media thickness and lumen diameter were derived from fixed sections using quantitative morphometry. Wall force was measured using a resistance artery myograph. The ratio of media thickness to lumen diameter and of maximum tension developed to lumen diameter both increased as vessel diameter decreased. These ratios do not change over the age range of 15-75 years. These findings show that although in vivo intralumenal pressure falls as human pial arteries become smaller, their media thickness and capacity to develop tone increase. PMID:10503931

  1. 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.

  2. Interfacial heat transfer in squeeze casting of magnesium alloy AM60 with variation of applied pressures and casting wall-thicknesses

    NASA Astrophysics Data System (ADS)

    Zhang, Xuezhi; Fang, Li; Sun, Zhizhong; Hu, Henry; Nie, Xueyuan; Tjong, Jimi

    2015-12-01

    The heat transfer coefficient at the casting-die interface is the most important factor on the solidification process. With the 75-ton hydraulic press machine and P20 steel die mold, 5-step castings of magnesium alloy AM60 with different wall-thicknesses (3, 5, 8, 12, 20 mm) were poured under various hydraulic pressures (30, 60, and 90 MPa) using an indirect squeeze casting process. Thermal histories throughout the die wall and the casting surface have been recorded by fine type-K thermocouples. The in-cavity local pressures measured by pressure transducers were explored at the casting-die interfaces of 5 steps. The casting-die interfacial heat transfer coefficients (IHTC) initially reached a maximum peak value followed by a gradually decline to the lower level. Similar characteristics of IHTC peak values can be observed at the applied pressures of 30, 60 and 90 MPa. With the applied pressure of 90 MPa, the peak IHTC values from steps 1 to 5 varied from 5623 to 10,649 W/m2 K. As the applied hydraulic pressure increased, the IHTC peak value of each step was increased accordingly. The wall thickness also affected IHTC peak values significantly. The peak IHTC value and heat flux increased as the step became thicker. The empirical equations relating the IHTCs to the local pressures and the solidification temperature at the casting surface were developed based on the multivariate linear and polynomial regression.

  3. Reconstruction option of abdominal wounds with large tissue defects

    PubMed Central

    2014-01-01

    Background Abdominal wall defects result from trauma, abdominal wall tumors, necrotizing infections or complications of previous abdominal surgeries. Apart from cosmetics, abdominal wall defects have strong negative functional impact on the patients. Many different techniques exist for abdominal wall repair. Most problematic and troublesome are defects, where major part of abdominal wall had to be resected and tissue for transfer or reconstruction is absent. Case presentation Authors of the article present operative technique, in which reconstruction of abdominal wall was managed by composite polypropylene mesh with absorbable collagen film, creation of granulation tissue with use of NPWT (negative pressure wound therapy), and subsequent split skin grafting. Three patients with massive abdominal wall defect were successfully managed and abdominal wall reconstruction was performed by mentioned technique. Functional and cosmetic effect is acceptable and patients have good postoperative quality of life. Conclusions Patients with giant abdominal defects can benefit from described technique. It serves as the only option, with which abdominal wall is fully reconstructed without need for the secondary intervention. PMID:25103782

  4. Abdominal sounds

    MedlinePlus

    ... blood flow. For example, blood clots can cause mesenteric artery occlusion . Mechanical bowel obstruction is caused by ... abdominal distention ? Do you have excessive or absent gas (flatus) ? Have you noticed any bleeding from the ...

  5. Development of a Versatile Laser-Ultrasonic System and Application to the Online Measurement for Process Control of Wall Thickness and Eccentricity of Seamless Tubes

    SciTech Connect

    Robert V. Kolarik II

    2002-10-23

    A system for the online, non-contact measurement of wall thickness in steel seamless mechanical tubing has been developed and demonstrated at a tubing production line at the Timken Company in Canton, Ohio. The system utilizes laser-generation of ultrasound and laser-detection of time of flight with interferometry, laser-doppler velocimetry and pyrometry, all with fiber coupling. Accuracy (<1% error) and precision (1.5%) are at targeted levels. Cost and energy savings have exceeded estimates. The system has shown good reliability in measuring over 200,000 tubes in its first six months of deployment.

  6. Acute incarcerated external abdominal hernia

    PubMed Central

    Yang, Xue-Fei

    2014-01-01

    External abdominal hernia occurs when abdominal organs or tissues leave their normal anatomic site and protrude outside the skin through the congenital or acquired weakness, defects or holes on the abdominal wall, including inguinal hernia, umbilical hernia, femoral hernia and so on. Acute incarcerated hernia is a common surgical emergency. With advances in minimally invasive devices and techniques, the diagnosis and treatment have witnessed major changes, such as the use of laparoscopic surgery in some cases to achieve minimally invasive treatment. However, strict adherence to the indications and contraindications is still required. PMID:25489584

  7. Analysis of transient heat flow to thick-walled plates and cylinders. [to determine gas heat transfer coefficient

    NASA Technical Reports Server (NTRS)

    Powell, W. B.

    1973-01-01

    A methodology is described for the analysis of a transient temperature measurement made in a flat or curved plate subjected to convective heat transfer, such that the surface heat flux, the hot-gas temperture, and the gas heat transfer coefficient can be determined. It is shown that if the transient temperature measurement is made at a particular point located nearly midway in the thickness of the plate there is an important simplification in the data analysis process, in that the factor relating the surface heat flux to the measured rate of rise of temperature becomes invariant for a Fourier Number above 0.60 and for all values of the Biot Number. Parameters are derived, tabulated, and plotted which enable straightforward determination of the surface heat flux, the hot-gas temperature, of the plate, the rate of rise of temperature, the plate thickness and curvature, and the mean thermal properties of the plate material at the test temperature.

  8. Fibrolipomas masquerading as abdominal hernias

    PubMed Central

    Watson, Hannah Isabella; Saunders, Andrew John

    2013-01-01

    A 15-year-old Caucasian girl presented to her general practitioner with a tender, irreducible mass in the paraumbilical region. On examination, two small masses could be felt. She was referred to general surgery. Ultrasound imaging and MRI were unremarkable. However, clinical suspicion suggested multiple areas of abdominal wall herniation. The patient was admitted for elective surgery to exclude herniation. At operation, three subcutaneous masses were found but with no evidence of abdominal wall herniation. Histopathology results from the specimens showed mature adipose tissue mixed with fibrous deposits. There was no evidence of malignancy. A diagnosis of fibrolipoma was given. PMID:24343803

  9. Development of an in vivo tissue-engineered vascular graft with designed wall thickness (biotube type C) based on a novel caged mold.

    PubMed

    Furukoshi, Maya; Moriwaki, Takeshi; Nakayama, Yasuhide

    2016-03-01

    Small-diameter biotube vascular grafts developed by in-body tissue architecture had high patency at implantation into rabbit carotid arteries or rat abdominal aortas. However, the thin walls (34 ± 14 μm) of the original biotubes made their implantation difficult into areas with low blood flow volumes or low blood pressure due to insufficient mechanical strength to maintain luminal shape. In this study, caged molds with several windows were designed to prepare more robust biotubes. The molds were assembled with silicone tubes (external diameter 2 mm) and cylindrical covers (outer diameter 7 mm) with 12 linear windows (1 × 9 mm). After the molds were embedded into beagle dorsal subcutaneous pouches for 4 weeks, type C (cage) biotubes were obtained by completely extracting the surrounding connective tissues from the molds and removing the molds. The biotube walls (778 ± 31 μm) were formed at the aperture (width 1 mm) between the silicone rods and the covers by connective cell migration through the windows of the covers. Excellent mechanical properties (external pressure resistance, approximately 4 times higher than beagle native femoral arteries; burst strength, approximately 2 times higher than original biotubes) were obtained. In the acute phase of implantation of the biotubes into beagle femoral arteries, perfect patency was obtained with little stenosis and no aneurysmal dilation. The type C biotubes may be useful for implantation into peripheral arteries or veins in addition to aortas. PMID:26265146

  10. Analysis of thermal residual stress in a thick-walled ring of Duralcan-base Al-SiC functionally graded material

    SciTech Connect

    Fukui, Yasuyoshi; Watanabe, Yoshimi

    1996-12-01

    A ring-cutting test and an elastic theory were applied to evaluate the macroscopic residual stress in a thick-walled ring made of Al-SiC functionally graded material (FGM). The FGM ring specimens, with outer diameter 90 mm, radial thickness approximately 8.4 to 10 mm, and width 30 mm, were fabricated by the centrifugal casting method from an ingot of Duralcan F3D.20S of Al-20 vol pct SiC master composite. Because of a difference in centrifugal forces of SiC particles and of molten aluminum alloy, the rings had a graded composition of SiC particles in the radial direction. The volume fractions of SiC particles in each ring specimen varied in the range of 0 to 43 vol pct from the inner to the outer surface of the ring, depending on the applied mold spin speed. A ring diametral compression test was performed to validate an analytical formula based on the curved beam theory that can account for the graded properties of the material. Excellent agreement between the theory that can account for the graded properties of the material. Excellent agreement between the theory and the experiment was found. The residual stress was found to be generated by a cooling of {Delta}T = 140 K, which was from half the melting point corresponding stress-free condition to the ambient temperature. The hoop residual stresses in the FGM ring varied in the range of {minus}50 to +35 MPa and from tension at the inner surface to compression at the outer space because of the graded composition. With an increase in wall thickness and/or composition gradation, the residual stresses were found to increase.

  11. Abdominal thrusts

    MedlinePlus

    ... call 911 . If the person loses consciousness, start CPR . If you are not comfortable performing abdominal thrusts, ... American Red Cross. First Aid/CPR/AED Participant's Manual. 2nd ... Red Cross; 2014. Berg RA, Hemphill R, Abella BS, et al. Part 5: ...

  12. Abdominal cocoon.

    PubMed

    Katz, Christian B S; Diggory, Robert T; Samee, Abdus

    2014-01-01

    Intestinal obstruction secondary to cocoon formation is not common. We report a case of a patient who had presented with abdominal pain and distension accompanied by vomiting. Investigations, laparotomy and histology together revealed primary peritoneal carcinoma as the cause of the patient's symptoms. PMID:24682136

  13. Abdominal cocoon

    PubMed Central

    Katz, Christian B S; Diggory, Robert T; Samee, Abdus

    2014-01-01

    Intestinal obstruction secondary to cocoon formation is not common. We report a case of a patient who had presented with abdominal pain and distension accompanied by vomiting. Investigations, laparotomy and histology together revealed primary peritoneal carcinoma as the cause of the patient's symptoms. PMID:24682136

  14. The analysis of time-dependent creep in FGPM thick walled sphere under electro-magneto-thermo-mechanical loadings

    NASA Astrophysics Data System (ADS)

    Loghman, A.; Moradi, M.

    2013-08-01

    Time-dependent creep response of a smart sphere made of functionally graded piezoelectric material (FGPM) is investigated. The vessel is subjected to an internal pressure, a uniform temperature field, an electric potential and a uniform magnetic field. Under such a loading condition initial elastic stresses are locked in the vessel at zero time. Due to high temperature, creep evolution causes stress redistribution in the sphere which is followed by electric potential redistribution across the thickness of the sphere. History of radial stresses is always reflected by history of electric potential which can be used for condition monitoring of the smart sphere. From the initial elastic stresses it has been found that imposing an electric potential decreases effective stresses. It has also been concluded from history of electric potential that electric potential redistribution is decreasing due to creep evolution and therefore this is followed by increasing effective stresses.

  15. Estimation of PSD Shifts for High-Resolution Metrology of Thickness Micro-Changes with Possible Applications in Vessel Walls and Biological Membrane Characterization

    PubMed Central

    Ramos, Antonio; Bazán, Ivonne; Negreira, Carlos; Brum, Javier; Gómez, Tomás; Calás, Héctor; Ruiz, Abelardo; de la Rosa, José Manuel

    2012-01-01

    Achieving accurate measurements of inflammation levels in tissues or thickness changes in biological membranes (e.g., amniotic sac, parietal pleura) and thin biological walls (e.g., blood vessels) from outside the human body, is a promising research line in the medical area. It would provide a technical basis to study the options for early diagnosis of some serious diseases such as hypertension, atherosclerosis or tuberculosis. Nevertheless, achieving the aim of non-invasive measurement of those scarcely-accessible parameters on patient internal tissues, currently presents many difficulties. The use of high-frequency ultrasonic transducer systems appears to offer a possible solution. Previous studies using conventional ultrasonic imaging have shown this, but the spatial resolution was not sufficient so as to permit a thickness evaluation with clinical significance, which requires an accuracy of a few microns. In this paper a broadband ultrasonic technique, that was recently developed by the authors to address other non-invasive medical detection problems (by integrating a piezoelectric transducer into a spectral measuring system), is extended to our new objective; the aim is its application to the thickness measurement of sub-millimeter membranes or layers made of materials similar to some biological tissues (phantoms). The modeling and design rules of such a transducer system are described, and various methods of estimating overtones location in the power spectral density (PSD) are quantitatively assessed with transducer signals acquired using piezoelectric systems and also generated from a multi-echo model. Their effects on the potential resolution of the proposed thickness measuring tool, and their capability to provide accuracies around the micron are studied in detail. Comparisons are made with typical tools for extracting spatial parameters in laminar samples from echo-waveforms acquired with ultrasonic transducers. Results of this advanced measurement spectral tool are found to improve the performance of typical cross-correlation methods and provide reliable and high-resolution estimations. PMID:23202216

  16. Steam-assisted crystallization of TPA{sup +}-exchanged MCM-41 type mesoporous materials with thick pore walls

    SciTech Connect

    Chen, Hong Li; Zhang, Kun; Wang, Yi Meng

    2012-07-15

    Highlights: ► Mesoporous Ti-containing silica with thicker pore walls was synthesized. ► Ion-exchange and steam-assisted crystallization led to MCM-41/MFI composite. ► The introduction of Ti inhibited the formation of separated MFI particles. ► Lower temperature favored retaining mesoporous characteristics and morphology. -- Abstract: Hierarchical MCM-41/MFI composites were synthesized through ion-exchange of as-made MCM-41 type mesoporous materials with tetrapropylammonium bromide and subsequent steam-assisted recrystallization. The obtained samples were characterized by powder X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis, FT-IR, {sup 1}H–{sup 13}C CP/MAS and nitrogen adsorption–desorption. The XRD patterns show that the MCM-41/MFI composite possesses both ordered MCM-41 phase and zeolite MFI phase. SEM and TEM images indicate that the recrystallized materials retained the mesoporous characteristics and the morphology of as-made mesoporous materials without the formation of bulky zeolite, quite different from the mechanical mixture of MCM-41 and MFI structured zeolite. Among others, lower recrystallization temperature and the introduction of the titanium to the parent materials are beneficial to preserve the mesoporous structure during the recrystallization process.

  17. Abdominal Aortic Aneurysms: Treatments

    MedlinePlus

    ... information Membership Directory (SIR login) Interventional Radiology Abdominal Aortic Aneurysms Interventional Radiologists Treat Abdominal Aneurysms Nonsurgically Interventional radiologists ...

  18. Extremal states of energy of a double-layered thick-walled tube - application to residually stressed arteries.

    PubMed

    Waffenschmidt, Tobias; Menzel, Andreas

    2014-01-01

    Various biological tissues are designed to optimally support external loads for complex geometries and mechanobiological structures. This results in complex microstructures of such materials. The design of, for instance, (healthy) arteries, which are in the focus of this work, is characterised by a residually stressed fibre-reinforced multi-layered composite with highly non-linear elastic response. The complex interaction of material properties with the geometry and residual stress effects enables the optimal support under different blood pressures, respectively blood flow, within the vessel. The fibres reinforcing the arterial wall, as well as residual stresses present in the vessel, strongly influence its overall behaviour and performance. Turn-over and remodelling processes of the collagenous fibres occurring in the respective layers - either resulting from natural growth phenomena or from artificially induced changes in loading condition such as stent deployment - support the optimisation of the multi-layered composite structure of arteries for the particular loading conditions present in the artery. Within this contribution, the overall energetic properties of an artery are discussed by means of the inflation, bending and extension of a double-layered cylindrical tube. Different states of residual stresses and different fibre orientations are considered so that, for instance, representative fibre angles that result in extremal states of the total potential energy can be identified. In view of turn-over and remodelling processes, these orientations are considered to constitute preferred directions of fibre alignment. In summary, the main goal of this work is to calculate optimal material, structural and loading parameters by concepts of energy-minimisation. Several numerical studies show that the obtained values - such as the fibre orientations, the residual axial stretch and the opening angle - are in good agreement with respective physiological parameters reported in the literature. PMID:23845915

  19. [Abdominal pain].

    PubMed

    Beer, D; Bettschart, V

    2001-01-01

    The doctor on duty conducting home visits is frequently asked to care for patients with non-traumatic severe abdominal pain. For this reason, visiting doctors should be able to recognize tell-tale alarm signs, evaluate ailments that call for surgical referral to--particularly those that require emergency surgery--and, if necessary, perform simple paraclinical exams at the patient's bedside. In the case of intense abdominal pain requiring a rapid and effective "analgesia", the doctor should be able to administer an opiate, without of the surgical unit impairing the judgement. When hospitalisation or referral for surgery is not necessary, a re-evaluation at 12 to 36 hours later should be offered. PMID:11234707

  20. A new multichannel time reversal focusing method for circumferential Lamb waves and its applications for defect detection in thick-walled pipe with large-diameter.

    PubMed

    Liu, Zenghua; Xu, Qinglong; Gong, Yu; He, Cunfu; Wu, Bin

    2014-09-01

    This paper proposes a new multichannel time reversal focusing (MTRF) method for circumferential Lamb waves which is based on modified time reversal algorithm and applies this method for detecting different kinds of defects in thick-walled pipe with large-diameter. The principle of time reversal of circumferential Lamb waves in pipe is presented along with the influence from multiple guided wave modes and propagation paths. Experimental study is carried out in a thick-walled and large-diameter pipe with three artificial defects, namely two axial notches on its inner and outer surface respectively, and a corrosion-like defect on its outer surface. By using the proposed MTRF method, the multichannel signals focus at the defects, leading to the amplitude improvement of the defect scattered signal. Besides, another energy focus arises in the direct signal due to the partial compensation of dispersion and multimode of circumferential Lamb waves, alongside the multichannel focusing, during MTRF process. By taking the direct focus as a time base, accurate defect localization is implemented. Secondly, a new phenomenon is exhibited in this paper that defect scattered wave packet appears just before the right boundary of truncation window after time reversal, and to which two feasible explanations are given. Moreover, this phenomenon can be used as the theoretical basis in the determination of defect scattered waves in time reversal response signal. At last, in order to detect defects without prior knowing their exact position, a large-range truncation window is used in the proposed method. As a result, the experimental operation of MTRF method is simplified and defect detection and localization are well accomplished. PMID:24877582

  1. Automated airway evaluation system for multi-slice computed tomography using airway lumen diameter, airway wall thickness and broncho-arterial ratio

    NASA Astrophysics Data System (ADS)

    Odry, Benjamin L.; Kiraly, Atilla P.; Novak, Carol L.; Naidich, David P.; Lerallut, Jean-Francois

    2006-03-01

    Pulmonary diseases such as bronchiectasis, asthma, and emphysema are characterized by abnormalities in airway dimensions. Multi-slice computed tomography (MSCT) has become one of the primary means to depict these abnormalities, as the availability of high-resolution near-isotropic data makes it possible to evaluate airways at oblique angles to the scanner plane. However, currently, clinical evaluation of airways is typically limited to subjective visual inspection only: systematic evaluation of the airways to take advantage of high-resolution data has not proved practical without automation. We present an automated method to quantitatively evaluate airway lumen diameter, wall thickness and broncho-arterial ratios. In addition, our method provides 3D visualization of these values, graphically illustrating the location and extent of disease. Our algorithm begins by automatic airway segmentation to extract paths to the distal airways, and to create a map of airway diameters. Normally, airway diameters decrease as paths progress distally; failure to taper indicates abnormal dilatation. Our approach monitors airway lumen diameters along each airway path in order to detect abnormal profiles, allowing even subtle degrees of pathologic dilatation to be identified. Our method also systematically computes the broncho-arterial ratio at every terminal branch of the tree model, as a ratio above 1 indicates potentially abnormal bronchial dilatation. Finally, the airway wall thickness is computed at corresponding locations. These measurements are used to highlight abnormal branches for closer inspection, and can be summed to compute a quantitative global score for the entire airway tree, allowing reproducible longitudinal assessment of disease severity. Preliminary tests on patients diagnosed with bronchiectasis demonstrated rapid identification of lack of tapering, which also was confirmed by corresponding demonstration of elevated broncho-arterial ratios.

  2. Abdominal trauma by ostrich

    PubMed Central

    Usurelu, Sergiu; Bettencourt, Vanessa; Melo, Gina

    2015-01-01

    Introduction Ostriches typically avoid humans in the wild, since they correctly assess humans as potential predators, and, if approached, often run away. However, ostriches may turn aggressive rather than run when threatened, especially when cornered, and may also attack when they feel the need to defend their offspring or territories. Presentation of case A 71-year-old male patient presented with intra abdominal injury sustained from being kicked in the abdominal wall by an ostrich. During laparotomy, were found free peritoneal effusion and perforation of the small intestine. Discussion The clinical history and physical examination are extremely important for diagnostic and therapeutic decision making. CT-scan is the most accurate exam for making diagnosis. Surgery is the treatment of choice, and is always indicated when there is injury to the hollow viscera. In general it is possible to suture the defect. Conclusion In cases of blunt abdominal trauma by animals is necessary to have a low threshold of suspicion for acute abdomen. PMID:25685344

  3. Unexpected multiple intra-abdominal injuries after projectile fragmentation: report of three cases.

    PubMed

    Unlü, Aytekin; Petrone, Patrizio; Karşıdağ, Tamer; Asensio, Juan A

    2012-11-01

    Explosives create and energize particles that act as projectiles prone to further fragmentation or create other secondary missiles in the body. These fragments may result in secondary injuries. This has been repeatedly described in the orthopedic and neurosurgical literature. We report the same process for abdominal injuries after fascial penetration in the military setting. This is an observational case series study. Local wound exploration as a standard approach was performed in conscious patients who sustained abdominal wall injuries. Patients with negative physical examination were excluded from the study. An intraperitoneal injury was assumed in those with a full-thickness fascial defect, and laparotomy was performed. Twenty patients met the study eligibility criteria. Of those 20 patients, 12 had negative wound exploration and were excluded from the study, while abdominal organ injuries were found in eight (40%) patients. During laparotomy, projectile-induced injuries in a sprayed distribution were found in three (38%) of these patients. These injuries were far from the predictable trajectory and in the absence of bone fragmentation. The overall mean number of peritoneal defects was 1.7, and a mean 6.8 intra-abdominal injuries for each peritoneal defect were found when through-and-through injuries were excluded.Despite a single peritoneal defect, there may be multiple intraperitoneal injuries due to further fragmentation of the projectile. Under mass casualties, wound exploration with a full-thickness fascial defect could serve as an indicator of possible intra-abdominal injuries, and consequently indicate exploratory laparotomy. PMID:23588915

  4. Abdominal rigidity

    MedlinePlus

    Causes can include: Abscess inside the abdomen Appendicitis Cholecystitis caused by gallstones Hole that develops through the entire wall of the stomach, small intestine, large bowel, or gallbladder ( gastrointestinal perforation ) Injury ...

  5. Abdominal exploration in captive collared peccaries (Tayassu tajacu) by ultrasonography.

    PubMed

    Peixoto, G C X; Oliveira, I R S; Alves, N D; Oliveira, M F; Silva, A R

    2012-08-01

    This study determines the morphology and ultrasound features of the abdominal organs in male, nestling and healthy collared peccaries. The bladder wall is hyperechogenic, with a thickness of 0.2 ± 0.08 cm. The kidneys present a well-defined cortex, medulla and pelvis, and the dimensions are 2.56 ± 0.3 × 4.6 ± 0.8 cm for the left and 2.51 ± 0.4 × 4.86 ± 1.1 cm for the right kidney. The spleen has a uniform echotexture over its entire surface. The largest dimensions of the liver are 2.0 ± 0.57 cm for the left lobe and 1.42 ± 0.66 cm for the caudate lobe. The liver presents a homogeneous echotexture in the majority of cases, but sometimes some hyperechoic spots are present. The stomach wall has a thickness of 0.42 ± 0.28 cm. The bowel loops show alternate hyperechoic and hypoechoic layers with a uniform diameter and a wall thickness of 0.19 ± 0.07 cm. PMID:22220558

  6. Effects of the changes in the wall shear stresses (WSS) acting on endothelial cells (EC) during the enlargement of Abdominal Aortic Aneurysms (AAA)

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie

    2005-03-01

    The changes in the spatial and temporal distribution of the WSS and gradients of WSS during the enlargement of AAAs are important to understand the etiology and progression of this vascular disease, since they affect the wall structural integrity, primarily via the changes induced on the shape, functions and metabolism of the endothelial cells. PIV measurements were performed in aneurysm models, while changing systematically their size and geometry. Two regions with distinct patterns of WSS were identified. The region of flow detachment extends over the proximal half and is characterized by oscillatory WSS of very low mean. The region of flow reattachment, located distally, is dominated by large, negative WSS and sustained gradients of WSS that result from the impact of the vortex ring on the wall. Cultured EC were subjected to these two types of stimuli in vitro. The permeability of the endothelium was found to be largely increased in the flow detachment region. Endothelium cell-cell adhesion, proliferation and apoptosis were also affected by the high gradients of WSS.

  7. Development of a Versatile Laser Ultrasonic System and Application to On-Line Measurement for Process Control of Wall Thickness and Eccentrictiy of Steel Seamless Mechanical Tubing

    SciTech Connect

    Kisner, R.A.; Kercel, S.W.; Damiano, B.; Bingham, P.R.; Gee, T.F.; Tucker, R.W.; Moore, M.R.; Hileman, M.; Emery, M.; Lenarduzzi, R.; Hardy, J.E.; Weaver, K.; Crutcher, R.; Kolarik, R.V., II; Vandervaart, R.H.

    2002-04-24

    Researchers at the Timken Company conceived a project to develop an on-line instrument for wall thickness measurement of steel seamless mechanical tubing based on laser ultrasonic technology. The instrument, which has been installed and tested at a piercing mill, provides data on tube eccentricity and concentricity. Such measurements permit fine-tuning of manufacturing processes to eliminate excess material in the tube wall and therefore provide a more precisely dimensioned product for their customers. The resulting process energy savings are substantial, as is lowered environmental burden. The expected savings are $85.8 million per year in seamless mechanical tube piercing alone. Applied across the industry, this measurement has a potential of reducing energy consumption by 6 x 10{sup 12} BTU per year, greenhouse gas emissions by 0.3 million metric tons carbon equivalent per year, and toxic waste by 0.255 million pounds per year. The principal technical contributors to the project were the Timken Company, Industrial Materials Institute (IMI, a contractor to Timken), and Oak Ridge National Laboratory (ORNL). Timken provided mill access as well as process and metallurgical understanding. Timken researchers had previously developed fundamental ultrasonic analysis methods on which this project is based. IMI developed and fabricated the laser ultrasonic generation and receiver systems. ORNL developed Bayesian and wavelet based real-time signal processing, spread-spectrum wireless communication, and explored feature extraction and pattern recognition methods. The resulting instrument has successfully measured production tubes at one of Timken's piercing mills. This report concentrates on ORNL's contribution through the CRADA mechanism. The three components of ORNL's contribution were met with mixed success. The real-time signal-processing task accomplished its goal of improvement in detecting time of flight information with a minimum of false data. The signal processing algorithm development resulted in a combination of processing steps that can be set to generate no spoofs from noise, while simultaneously missing fewer than 10% of good trials. The algorithm leads to a 95% probability that the estimate of time of flight is good to within 4 time bins or fewer for laser excitations above 30 mJ for the first two echoes of the signal. Receiver Operating Characteristic (ROC) curves for the algorithm indicate that the algorithm is very robust against errors for excitations above at 35 mJ and above, tolerable at 30 mJ and unacceptable below 30 mJ.

  8. Drought-induced increase in water-use efficiency reduces secondary tree growth and tracheid wall thickness in a Mediterranean conifer.

    PubMed

    Olano, José Miguel; Linares, Juan Carlos; García-Cervigón, Ana I; Arzac, Alberto; Delgado, Antonio; Rozas, Vicente

    2014-09-01

    In order to understand the impact of drought and intrinsic water-use efficiency (iWUE) on tree growth, we evaluated the relative importance of direct and indirect effects of water availability on secondary growth and xylem anatomy of Juniperus thurifera, a Mediterranean anisohydric conifer. Dendrochronological techniques, quantitative xylem anatomy, and (13)C/(12)C isotopic ratio were combined to develop standardized chronologies for iWUE, BAI (basal area increment), and anatomical variables on a 40-year-long annually resolved series for 20 trees. We tested the relationship between iWUE and secondary growth at short-term (annual) and long-term (decadal) temporal scales to evaluate whether gains in iWUE may lead to increases in secondary growth. We obtained a positive long-term correlation between iWUE and BAI, simultaneously with a negative short-term correlation between them. Furthermore, BAI and iWUE were correlated with anatomical traits related to carbon sink or storage (tracheid wall thickness and ray parenchyma amount), but no significant correlation with conductive traits (tracheid lumen) was found. Water availability during the growing season significantly modulated tree growth at the xylem level, where growth rates and wood anatomical traits were affected by June precipitation. Our results are consistent with a drought-induced limitation of tree growth response to rising CO2, despite the trend of rising iWUE being maintained. We also remark the usefulness of exploring this relationship at different temporal scales to fully understand the actual links between iWUE and secondary growth dynamics. PMID:24958369

  9. 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. PMID:9135238

  10. CT of abdominal tuberculosis

    SciTech Connect

    Epstein, B.M.; Mann, J.H.

    1982-11-01

    Intraabdominal tuberculosis (TB) presents with a wide variety of clinical and radiologic features. Besides the reported computed tomographic (CT) finding of high-density ascites in tuberculous peritonitis, this report describes additional CT features highly suggestive of abdominal tuberculosis in eight cases: (1) irregular soft-tissue densities in the omental area; (2) low-density masses surrounded by thick solid rims; (3) a disorganized appearance of soft-tissue densities, fluid, and bowel loops forming a poorly defined mass; (4) low-density lymph nodes with a multilocular appearance after intravenous contrast administration; and (5) possibly high-density ascites. The differential diagnosis of these features include lymphoma, various forms of peritonitis, peritoneal carcinomatosis, and peritoneal mesothelioma. It is important that the CT features of intraabdominal tuberculosis be recognized in order that laparotomy be avoided and less invasive procedures (e.g., laparoscopy, biopsy, or a trial of antituberculous therapy) be instituted.

  11. Multiple bowel perforation and necrotising fasciitis secondary to abdominal liposuction in a patient with bilateral lumbar hernia

    PubMed Central

    Dellière, Vincent; Bertheuil, N.; Harnois, Y.; Thiénot, S.; Gérard, M.; Robert, M.; Watier, E.

    2014-01-01

    We present a rare complication of abdominal liposuction: bowel perforation and necrotizing fasciitis. Because of bilateral lumbar hernia, a 56-year-old woman had caecum and descending colon perforation during lipoplasty. She had septic shock syndrome at her admission. The authors treated this complex wound with several debridement, omental flap, NPWT and split-thickness skin graft. The incidence of abdominal wall perforation with visceral injury is 14 in 100,000 liposuctions performed. There are only 12 cases of bowel perforation in literature but this complication is probably underestimated. Prompt surgical debridement is absolutely mandatory in this life threatening scenario. Lumbar hernia is very rare and should be ruled out before every abdominal liposuction clinically or with imaging modalities. PMID:25593436

  12. Assessing abdominal aorta narrowing using computational fluid dynamics.

    PubMed

    Al-Rawi, Mohammad; Al-Jumaily, Ahmed M

    2016-05-01

    This paper investigates the effect of developing arterial blockage at the abdominal aorta on the blood pressure waves at an externally accessible location suitable for invasive measurements such as the brachial and the femoral arteries. Arterial blockages are created surgically within the abdominal aorta of healthy Wistar rats to create narrowing resemblance conditions. Blood pressure is measured using a catheter inserted into the right femoral artery. Measurements are taken at the baseline healthy condition as well as at four different severities (20, 50, 80 and 100 %) of arterial blockage. In vivo and in vitro measurements of the lumen diameter and wall thickness are taken using magnetic resonance imaging and microscopic techniques, respectively. These data are used to validate a 3D computational fluid dynamics model which is developed to generalize the outcomes of this work and to determine the arterial stress and strain under the blockage conditions. This work indicates that an arterial blockage in excess of 20 % of the lumen diameter significantly influences the pressure wave and reduces the systolic blood pressure at the right femoral artery. High wall shear stresses and low circumferential strains are also generated at the blockage site. PMID:26319006

  13. Abdominal aortic aneurysm

    MedlinePlus

    ... blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ... High blood pressure Male gender Genetic factors An abdominal aortic aneurysm is most often seen in males over age ...

  14. The Effects of Neuromuscular Electrical Stimulation Training on Abdominal Strength, Endurance, and Selected Anthropometric Measures

    PubMed Central

    Porcari, John P.; Miller, Jennifer; Cornwell, Kelly; Foster, Carl; Gibson, Mark; McLean, Karen; Kernozek, Tom

    2005-01-01

    We studied the effects of self-administered neuromuscular electrical stimulation (NMES) on changes in strength, endurance, selected anthropometric measures, and subject’s perceived shape and satisfaction of the abdominal wall. Twenty-four adults (experimental group) stimulated their abdominals 5 days per week (20-40 minutes per session) for 8 weeks and refrained from engaging in any additional exercise during the study. A control group (N=16) refrained from exercising the abdominals or engaging in any other exercise training during the study. Subjects were tested at the beginning, mid-point, and end of the study. Isometric strength of the abdominal muscles was tested using a isokinetic dynamometer, endurance was measured using the ACSM curl-up test, abdominal circumference was measured using a steel tape measure, and body shape and satisfaction were assessed via questionnaire. The stimulation group had a 58% increase in abdominal strength, whereas the control group did not change. The stimulation group also had a 100% increase in abdominal endurance versus a 28% increase in the control group. Waist circumference decreased by of 3.5 cm in the stimulation group compared to no significant change in the control group. All 24 subjects in the stimulation group felt that their midsections were more “toned” and “firmed” and 13/24 (54%) felt that their posture had improved as a result of the stimulation. None of the control group subjects reported changes in these parameters. There were no significant differences in body weight, BMI, or skinfold thickness over the course of the study in either group. NMES, as used in the current study, resulted in significant improvements in the muscular strength and endurance of the abdominal region, as well as subject’s perceived shape and satisfaction of the mid-section. Key Points Electrical muscle stimulation (EMS) was effective in increasing muscle strength and endurance All subjects perceived their abdominal muscles to be firmer and more toned as a result of EMS Abdominal and waist girth was also significantly reduced, despite no changes in body weight or subcutaneous fat PMID:24431963

  15. Component Separation for Complex Abdominal Wall Reconstruction

    MedlinePlus Videos and Cool Tools

    ... is that we are actually here for the prep and drape of these cases. We help them with that. The prep has to be pretty wide; all the way ... down to the pubis is where we'll prep them, and that just gives us room to ...

  16. Merkel cell carcinoma of the abdominal wall

    PubMed Central

    Gaopande, Vandana L.; Joshi, Avinash R.; Khandeparkar, Siddhi G. S.; Deshmukh, Sanjay D.

    2015-01-01

    Merkel cell carcinoma also known as neuroendocrine carcinoma of the skin is a very rare skin tumor. It commonly presents in the old age and the common sites are head, neck and extremities. The diagnosis requires histopathological examination with immunohistochemical correlation. We report a case of Merkel cell carcinoma stage IIIB with bilateral inguinal lymphadenopathy that on FNAB showed metastatic deposits of the tumor. PMID:26225333

  17. Fermion localization on thick branes

    SciTech Connect

    Melfo, Alejandra; Pantoja, Nelson; Tempo, Jose David

    2006-02-15

    We consider chiral fermion confinement in scalar thick branes, which are known to localize gravity, coupled through a Yukawa term. The conditions for the confinement and their behavior in the thin-wall limit are found for various different BPS branes, including double walls and branes interpolating between different AdS{sub 5} spacetimes. We show that only one massless chiral mode is localized in all these walls, whenever the wall thickness is keep finite. We also show that, independently of wall's thickness, chiral fermionic modes cannot be localized in dS{sub 4} walls embedded in a M{sub 5} spacetime. Finally, massive fermions in double wall spacetimes are also investigated. We find that, besides the massless chiral mode localization, these double walls support quasilocalized massive modes of both chiralities.

  18. Effect of ratio of wall boundary layer thickness to jet diameter on mixing of a normal hydrogen jet in a supersonic stream

    NASA Technical Reports Server (NTRS)

    Mcclinton, C. R.

    1974-01-01

    A preliminary experimental program was conducted to determine the effect of the ratio of the free-stream boundary-layer thickness to jet diameter on the secondary jet penetration and mixing rate. Tests were conducted on a flat plate in a Mach number 4.05 airflow with sonic injection of hydrogen normal to the free-stream direction from circular underexpanded injectors. The ratio of boundary-layer thickness to jet diameter ranged from 1.25 to 6.5. Previous correlations of mixing performance were modified to account for the effect of the ratio of boundary-layer thickness to jet diameter.

  19. Abdominal Circulatory Interactions.

    PubMed

    Dagar, Gaurav; Taneja, Amit; Nanchal, Rahul S

    2016-04-01

    The abdominal compartment is separated from the thoracic compartment by the diaphragm. Under normal circumstances, a large portion of the venous return crosses the splanchnic and nonsplanchnic abdominal regions before entering the thorax and the right side of the heart. Mechanical ventilation may affect abdominal venous return independent of its interactions at the thoracic level. Changes in pressure in the intra-abdominal compartment may have important implications for organ function within the thorax, particularly if there is a sustained rise in intra-abdominal pressure. It is important to understand the consequences of abdominal pressure changes on respiratory and circulatory physiology. This article elucidates important abdominal-respiratory-circulatory interactions and their clinical effects. PMID:27016167

  20. Influence of Selective Biochemical and Morphological Agents on Natural History of Aneurysm of Abdominal Aorta Development

    PubMed Central

    Wołoszko, Tomasz; Skórski, Maciej; Kwasiborski, Przemysław; Kmin, Ewelina; Gałązka, Zbigniew; Pogorzelski, Ryszard

    2016-01-01

    Background The development of abdominal aortic aneurysm (AAA) is probably influenced by many factors. The role of some of these factors, such as intraluminal thrombus (ILT) or cystatin C serum levels, remains controversial. Proving their influence could have therapeutic implications for some patients with AAA. Associations between the rate of increase in diameter of an aneurysm and ILT, as well as other factors, including biochemical factors (C-Reactive Protein – CRP, cystatin C), age, sex, and comorbidities, could predict disease progression in individual patients. Material/Methods Seventy patients with small AAA were included into the study. The patients were followed using ultrasound and CT imaging. We evaluated aneurysm dimensions and aneurysm wall thickness, as well as ILT and its dimensions, aneurysm wall morphology, CRP, and cystatin C. Results We observed significant growth of AAA and thinning of aneurysmal wall. Aneurysms over 4 cm grew significantly faster in the second year of observation. ILT grew together with AAA size. Age, sex, smoking, dyslipidemias, or controlled arterial hypertension had no influence on aneurysm progression rate. Changes in serum of CRP concentration did not reach statistical significance, but cystatin C levels did. Conclusions Presence and size of ILT, wall thickness, and cystatin C levels may be considered in prediction of AAA progression. ILT might exert a protective influence on the risk of aneurysm rupture. However, larger aneurysms containing larger thrombi grow faster and their walls undergo more rapid degradation, which in turn increases the risk of rupture. This matter requires further studies. PMID:26859744

  1. Influence of Selective Biochemical and Morphological Agents on Natural History of Aneurysm of Abdominal Aorta Development.

    PubMed

    Wo?oszko, Tomasz; Skrski, Maciej; Kwasiborski, Przemys?aw; Kmin, Ewelina; Ga??zka, Zbigniew; Pogorzelski, Ryszard

    2016-01-01

    BACKGROUND The development of abdominal aortic aneurysm (AAA) is probably influenced by many factors. The role of some of these factors, such as intraluminal thrombus (ILT) or cystatin C serum levels, remains controversial. Proving their influence could have therapeutic implications for some patients with AAA. Associations between the rate of increase in diameter of an aneurysm and ILT, as well as other factors, including biochemical factors (C-Reactive Protein - CRP, cystatin C), age, sex, and comorbidities, could predict disease progression in individual patients. MATERIAL AND METHODS Seventy patients with small AAA were included into the study. The patients were followed using ultrasound and CT imaging. We evaluated aneurysm dimensions and aneurysm wall thickness, as well as ILT and its dimensions, aneurysm wall morphology, CRP, and cystatin C. RESULTS We observed significant growth of AAA and thinning of aneurysmal wall. Aneurysms over 4 cm grew significantly faster in the second year of observation. ILT grew together with AAA size. Age, sex, smoking, dyslipidemias, or controlled arterial hypertension had no influence on aneurysm progression rate. Changes in serum of CRP concentration did not reach statistical significance, but cystatin C levels did. CONCLUSIONS Presence and size of ILT, wall thickness, and cystatin C levels may be considered in prediction of AAA progression. ILT might exert a protective influence on the risk of aneurysm rupture. However, larger aneurysms containing larger thrombi grow faster and their walls undergo more rapid degradation, which in turn increases the risk of rupture. This matter requires further studies. PMID:26859744

  2. Effect of open-label infusion of an apoA-I-containing particle (CER-001) on RCT and artery wall thickness in patients with FHA[S

    PubMed Central

    Kootte, Ruud S.; Smits, Loek P.; van der Valk, Fleur M.; Dasseux, Jean-Louis; Keyserling, Constance H.; Barbaras, Ronald; Paolini, John F.; Santos, Raul D.; van Dijk, Theo H.; Dallinga-van Thie, Geesje M.; Nederveen, Aart J.; Mulder, Willem J. M.; Hovingh, G. Kees; Kastelein, John J. P.; Groen, Albert K.; Stroes, Erik S.

    2015-01-01

    Reverse cholesterol transport (RCT) contributes to the anti-atherogenic effects of HDL. Patients with the orphan disease, familial hypoalphalipoproteinemia (FHA), are characterized by decreased tissue cholesterol removal and an increased atherogenic burden. We performed an open-label uncontrolled proof-of-concept study to evaluate the effect of infusions with a human apoA-I-containing HDL-mimetic particle (CER-001) on RCT and the arterial vessel wall in FHA. Subjects received 20 infusions of CER-001 (8 mg/kg) during 6 months. Efficacy was assessed by measuring (apo)lipoproteins, plasma-mediated cellular cholesterol efflux, fecal sterol excretion (FSE), and carotid artery wall dimension by MRI and artery wall inflammation by 18F-fluorodeoxyglucose-positron emission tomography/computed tomography scans. We included seven FHA patients: HDL-cholesterol (HDL-c), 13.8 [1.8–29.1] mg/dl; apoA-I, 28.7 [7.9–59.1] mg/dl. Following nine infusions in 1 month, apoA-I and HDL-c increased directly after infusion by 27.0 and 16.1 mg/dl (P = 0.018). CER-001 induced a 44% relative increase (P = 0.018) in in vitro cellular cholesterol efflux with a trend toward increased FSE (P = 0.068). After nine infusions of CER-001, carotid mean vessel wall area decreased compared with baseline from 25.0 to 22.8 mm2 (P = 0.043) and target-to-background ratio from 2.04 to 1.81 (P = 0.046). In FHA-subjects, CER-001 stimulates cholesterol mobilization and reduces artery wall dimension and inflammation, supporting further evaluation of CER-001 in FHA patients. PMID:25561459

  3. The effects of neuromuscular electrical stimulation training on abdominal strength, endurance, and selected anthropometric measures.

    PubMed

    Porcari, John P; Miller, Jennifer; Cornwell, Kelly; Foster, Carl; Gibson, Mark; McLean, Karen; Kernozek, Tom

    2005-03-01

    We studied the effects of self-administered neuromuscular electrical stimulation (NMES) on changes in strength, endurance, selected anthropometric measures, and subject's perceived shape and satisfaction of the abdominal wall. Twenty-four adults (experimental group) stimulated their abdominals 5 days per week (20-40 minutes per session) for 8 weeks and refrained from engaging in any additional exercise during the study. A control group (N=16) refrained from exercising the abdominals or engaging in any other exercise training during the study. Subjects were tested at the beginning, mid-point, and end of the study. Isometric strength of the abdominal muscles was tested using a isokinetic dynamometer, endurance was measured using the ACSM curl-up test, abdominal circumference was measured using a steel tape measure, and body shape and satisfaction were assessed via questionnaire. The stimulation group had a 58% increase in abdominal strength, whereas the control group did not change. The stimulation group also had a 100% increase in abdominal endurance versus a 28% increase in the control group. Waist circumference decreased by of 3.5 cm in the stimulation group compared to no significant change in the control group. All 24 subjects in the stimulation group felt that their midsections were more "toned" and "firmed" and 13/24 (54%) felt that their posture had improved as a result of the stimulation. None of the control group subjects reported changes in these parameters. There were no significant differences in body weight, BMI, or skinfold thickness over the course of the study in either group. NMES, as used in the current study, resulted in significant improvements in the muscular strength and endurance of the abdominal region, as well as subject's perceived shape and satisfaction of the mid-section. Key PointsElectrical muscle stimulation (EMS) was effective in increasing muscle strength and enduranceAll subjects perceived their abdominal muscles to be firmer and more toned as a result of EMSAbdominal and waist girth was also significantly reduced, despite no changes in body weight or subcutaneous fat. PMID:24431963

  4. CT of abdominal tuberculosis.

    PubMed

    Epstein, B M; Mann, J H

    1982-11-01

    Intraabdominal tuberculosis (TB) presents with a wide variety of clinical and radiologic features. Besides the reported computed tomographic (CT) finding of high-density ascites in tuberculous peritonitis, this report describes additional CT features highly suggestive of abdominal tuberculosis in eight cases: (1)irregular soft-tissue densities in the omental area; (2) low-density masses surrounded by thick solid rims; (3) a disorganized appearance of soft-tissue densities, fluid, and bowel loops forming a disorganized appearance of soft-tissue densities, fluid, and bowel loops forming a poorly defined mass; (4) low-density lymph nodes with a multilocular appearance after intravenous contrast administration; and (5) possibly high-density ascites. The differential diagnosis of these features include lymphoma, various forms of peritonitis, peritoneal carcinomatosis, and peritoneal mesothelioma. It is important that the CT features of intraabdominal tuberculosis be recognized in order that laparotomy be avoided and less invasive procedures (e.g., laparoscopy, biopsy, or a trail of antituberculous therapy) be instituted. PMID:6981966

  5. Effects of D-4F on Vasodilation and Vessel Wall Thickness in Hypercholesterolemic LDL Receptor Null and LDL receptor/ApoA-I Double Knockout Mice on Western Diet

    PubMed Central

    Ou, Jingsong; Wang, Jingli; Xu, Hao; Ou, Zhijun; Sorci-Thomas, Mary G.; Jones, Deron W.; Signorino, Paul; Densmore, John C.; Kaul, Sushma; Oldham, Keith T.; Pritchard, Kirkwood A.

    2005-01-01

    Previously we showed L-4F, a novel apolipoprotein A-I (apoA-I) mimetic, improved vasodilation in two dissimilar models of vascular disease; hypercholesterolemic low-density lipoprotein (LDL) receptor null (Ldlr −/−) mice and transgenic sickle cell disease mice. Here we determine the mechanisms by which D-4F improves vasodilation and arterial wall thickness in hypercholesterolemic Ldlr −/− mice and Ldlr −/−/apoA-I null (apoA-I −/−), double knockout mice. Ldlr −/− and Ldlr −/−/apoA-I −/− mice were fed western diet (WD) ± D-4F. Oral D-4F restored endothelium- and eNOS-dependent vasodilation in direct relationship to duration of treatments and reduced wall thickness in as little as 2 weeks in vessels with pre-existing disease in Ldlr −/− mice. D-4F had no effect on total or HDL cholesterol concentrations but reduced proinflammatory HDL levels. D-4F had no effect on plasma myeloperoxidase (MPO) concentrations but reduced MPO association with apoA-I as well as 3-nitrotyrosine in apoA-I. D-4F increased endothelium- and eNOS-dependent vasodilation in Ldlr −/−/apoA-I −/− mice but did not reduce wall thickness as it had in Ldlr −/− mice. Vascular endothelial cells were treated with 22-hydroxycholesterol (22-OHC) ± L-4F. 22-OHC decreased nitric oxide (•NO) and increased superoxide anion (O2 •−) production and increased ABCA-1 and collagen expression. L-4F restored •NO and O2 •− balance, had little effect on ABCA-1 expression but reduced collagen expression. These data demonstrate that although D-4F restores vascular endothelial cell and eNOS function to increase vasodilation, HDL containing apoA-I, or at least some critical concentration of the anti-atherogenic lipoprotein, is required for D-4F to decrease vessel wall thickness. PMID:16224061

  6. Laparotomy for blunt abdominal trauma-some uncommon indications

    PubMed Central

    Dharap, Satish B.; Noronha, Jarin; Kumar, Vineet

    2016-01-01

    Trauma laparotomy after blunt abdominal trauma is conventionally indicated for patients with features of hemodynamic instability and peritonitis to achieve control of hemorrhage and control of spillage. In addition, surgery is clearly indicated for the repair of posttraumatic diaphragmatic injury with herniation. Some other indications for laparotomy have been presented and discussed. Five patients with blunt abdominal injury who underwent laparotomy for nonroutine indications have been presented. These patients were hemodynamically stable and had no overt signs of peritonitis. Three patients had solid organ (spleen, kidney) infarction due to posttraumatic occlusion of the blood supply. One patient had mesenteric tear with internal herniation of bowel loops causing intestinal obstruction. One patient underwent surgery for traumatic abdominal wall hernia. In addition to standard indications for surgery in blunt abdominal trauma, laparotomy may be needed for vascular thrombosis of end arteries supplying solid organs, internal or external herniation through a mesenteric tear or anterior abdominal wall musculature, respectively. PMID:26957824

  7. Secondary reconstruction with a transverse colon covered with a pectoralis major muscle flap and split thickness skin grafts for an esophageal defect and wide skin defects of the anterior chest wall.

    PubMed

    Sadanaga, Noriaki; Morinaga, Keigo; Matsuura, Hiroshi

    2015-12-01

    Necrosis of a reconstructed organ after esophagectomy is a rare postoperative complication. However, in case this complication develops, severe infectious complications can occur, and subsequent surgical reconstruction is quite complicated. To treat esophageal conduit necrosis after esophageal reconstruction with the terminal ileum and ascending colon, we reconstructed the esophagus using a transverse colon, which was covered with a pectoralis major muscle flap to reinforce the anastomotic site. In addition, split thickness skin grafts were applied to the wide skin defect to cover the reconstructed organs at the antesternal route. Widely extended split thickness skin grafts can adhere to the reconstructed organs without excessive tension. Therefore, this method enabled successful treatment of an esophageal defect and wide skin defects of the anterior chest wall. PMID:26943390

  8. Effect of rectal distension on abdominal girth.

    PubMed

    Marino, B; Ogliari, C; Basilisco, G

    2004-08-01

    It has been postulated that a viscerosomatic reflex activated by gut distension and inhibiting abdominal wall muscle tone may be one of the mechanisms underlying functional abdominal distension. Any demonstration of such a reflex has to take into account the fact that gut distension may increase abdominal girth as a result of volume displacement. As biomechanical and sensory rectal responses vary at different rates of rectal distension, we hypothesized that different rates of rectal distension might reveal different changes in abdominal girth. Abdominal girth was continuously recorded in 14 healthy subjects using a previously validated extensometer. The rectal distensions were made in a randomized order at rates of 100 mL min(-1) or 10 mL min(-1) up to 150 mL, and sham distensions were used as controls. An increase in abdominal girth was observed at the end of both distensions (P

  9. Abdominal aortic aneurysm in giant cell arteritis

    PubMed Central

    Kwon, Hyunwook; Han, Youngjin; Son, Da Hye; Cho, Yong-Pil

    2015-01-01

    Aortic complications of giant cell arteritis are a rare cause of abdominal aortic aneurysm. Here, we describe a case of a ruptured aortic aneurysm in a patient with giant call arteritis (GCA) who was preoperatively suspected of having an infectious aortic aneurysm. Intraoperative inspection revealed infectious granulation tissue on the anterior wall of the abdominal aorta. GCA was finally confirmed by pathological diagnosis. Our findings suggest that the surgical and postoperative treatment of nonatheromatous aortic aneurysm should be based on accurate diagnosis. PMID:26448922

  10. CT diagnosis of ruptured abdominal aortic aneurysm

    SciTech Connect

    Rosen, A.; Korobkin, M.; Silverman, P.M.; Moore, A.V. Jr.; Dunnick, N.R.

    1984-08-01

    Abdominal computed tomography was performed in six patients with suspected ruptured abdominal aortic aneurysm but in whom an alternate clinical diagnosis was seriously considered. In each patient, a large aortic aneurysm was demonstrated in association with a retroperitoneal accumulation of high-density blood. The retroperitoneal blood was primarily confined to the extracapsular perinephric space. In four of the six patients, a focal area of the aortic wall was indistinct on the side of the retroperitoneal hemorrhage at the presumed site of rupture. Five of the six patients underwent emergency surgery, which confirmed the site of aneurysm, presence of rupture and the location of fresh retroperitoneal blood.

  11. Continuous Processing of Multi-Walled Carbon Nanotube-Studded Carbon Fiber Tapes for Enhanced Through-Thickness Thermal Diffusivity Composites.

    PubMed

    Craddock, John D; Qian, Dali; Lester, Catherine; Matthews, JohnJ; Mansfield, J Patrick W; Foedinger, Richard; Weisenberger, Matthew C

    2015-09-01

    Carbon fiber reinforced polymer (CFRP) composites offer advantages over traditional metallic structures, particularly specific strength and stiffness, but at much reduced thermal conductivity. Moreover, fiber-to-fiber heat conduction in the composite transverse directions is significantly lower. When these structures contain electronics (heat generators), shortfalls in heat transport can be problematic. Here we report the achievement of a continuous, reel-to-reel process for growing short multiwalled carbon nanotubes (MWCNT) on the surfaces of spread-tow carbon fiber tapes. These tapes were subsequently prepregged with an epoxy matrix, and laid up into multi-ply laminate panels, cured and tested for through-thickness thermal diffusivity. The results showed up to a 57% increase in through thickness thermal diffusivity compared to the baseline composite with no MWCNT. PMID:26716256

  12. Wall surveyor project report

    SciTech Connect

    Mullenhoff, D.J.; Johnston, B.C.; Azevedo, S.G.

    1996-02-22

    A report is made on the demonstration of a first-generation Wall Surveyor that is capable of surveying the interior and thickness of a stone, brick, or cement wall. LLNL`s Micropower Impulse Radar is used, based on emitting and detecting very low amplitude and short microwave impulses (MIR rangefinder). Six test walls were used. While the demonstrator MIR Wall Surveyor is not fieldable yet, it has successfully scanned the test walls and produced real-time images identifying the walls. It is planned to optimize and package the evaluation wall surveyor into a hand held unit.

  13. K-wire assisted split-thickness skin graft harvesting from the anterior trunk.

    PubMed

    Yontar, Yalcin; Coruh, Atilla; Severcan, Mehmet

    2016-02-01

    Split thickness skin graft (STSG) harvesting from the anterior chest and abdominal wall skin is quite a difficult process. The main reason for the difficulty to perform this process is the unsuitable anatomic characteristics of the anterior trunk, such as irregular wavy-like surface over the ribs and lax abdominal wall skin resulting in collapse due to lack of adequate underneath supporting structures when a downward force is applied by the skin graft dermatome. Lower extremity and especially the thigh are generally chosen as the donor site where the STSGs are easily harvested from. However, extensive lower extremity burns, with or without other region burns, preclude harvesting auto STSGs from this invaluable anatomic site. We harvested K-wire assisted STSGs from the anterior chest and abdominal wall skin of 7 patients with lower extremity burns and also a patient that sustained motor vehicle collision. We encountered no problems in any of our patients both intra and postoperatively by using K-wire assisted STSG harvesting. All of the STSGs donor sites healed uneventfully without complications. In our opinion, K-wire assisted STSG harvesting must always be in the tool-box of any surgeon who deals with extensive burns with or without lower extremity burns and extensive traumas of lower extremities. PMID:26608017

  14. Recurrent Abdominal Pain

    ERIC Educational Resources Information Center

    Banez, Gerard A.; Gallagher, Heather M.

    2006-01-01

    The purpose of this article is to provide an empirically informed but clinically oriented overview of behavioral treatment of recurrent abdominal pain. The epidemiology and scope of recurrent abdominal pain are presented. Referral process and procedures are discussed, and standardized approaches to assessment are summarized. Treatment protocols…

  15. [Abdominal pregnancy, institutional experience].

    PubMed

    Bonfante Ramírez, E; Bolaños Ancona, R; Simón Pereyra, L; Juárez García, L; García-Benitez, C Q

    1998-07-01

    Abdominal pregnancy is a rare entity, which has been classified as primary or secondary by Studiford criteria. A retrospective study, between January 1989 and December 1994, realized at Instituto Nacional de Perinatología, found 35,080 pregnancies, from which 149 happened to be ectopic, and 6 of them were abdominal. All patients belonged to a low income society class, age between 24 and 35 years, and average of gestations in 2.6. Gestational age varied from 15 weeks to 32.2 weeks having only one delivery at term with satisfactory postnatal evolution. One patient had a recurrent abdominal pregnancy, with genital Tb as a conditional factor. Time of hospitalization varied from 4 to 5 days, and no further patient complications were reported. Fetal loss was estimated in 83.4%. Abdominal pregnancy is often the sequence of a tubarian ectopic pregnancy an when present, it has a very high maternal mortality reported in world literature, not found in this study. The stated frequency of abdominal pregnancy is from 1 of each 3372, up to 1 in every 10,200 deliveries, reporting in the study 1 abdominal pregnancy in 5846 deliveries. The study had two characteristic entities one, the recurrence and two, the delivery at term of one newborn. Abdominal pregnancy accounts for 4% of all ectopic pregnancies. Clinical findings in abdominal pregnancies are pain, transvaginal bleeding and amenorrea, being the cardinal signs of ectopic pregnancy. PMID:9737070

  16. Axial prestretch and circumferential distensibility in biomechanics of abdominal aorta.

    PubMed

    Horný, Lukáš; Netušil, Marek; Voňavková, Tereza

    2014-08-01

    Elastic arteries are significantly prestretched in an axial direction. This property minimises axial deformations during pressure cycle. Ageing-induced changes in arterial biomechanics, among others, are manifested via a marked decrease in the prestretch. Although this fact is well known, little attention has been paid to the effect of decreased prestretch on mechanical response. Our study presents the results of an analytical simulation of the inflation-extension behaviour of the human abdominal aorta treated as nonlinear, anisotropic, prestrained thin-walled as well as thick-walled tube with closed ends. The constitutive parameters and geometries for 17 aortas adopted from the literature were supplemented with initial axial prestretches obtained from the statistics of 365 autopsy measurements. For each aorta, the inflation-extension response was calculated three times, with the expected value of the initial prestretch and with the upper and lower confidence limit of the initial prestretch derived from the statistics. This approach enabled age-related trends to be evaluated bearing in mind the uncertainty in the prestretch. Despite significantly decreased longitudinal prestretch with age, the biomechanical response of human abdominal aorta changes substantially depending on the initial axial stretch was used. In particular, substituting the upper limit of initial prestretch gave mechanical responses which can be characterised by (1) low variation in axial stretch and (2) high circumferential distensibility during pressurisation, in contrast to the responses obtained for their weakly prestretched counterparts. The simulation also suggested the significant effect of the axial prestretch on the variation of axial stress in the pressure cycle. Finally, the obtained results are in accordance with the hypothesis that circumferential-to-axial stiffness ratio is the quantity relatively constant within this cycle. PMID:24136338

  17. Liquid Wall Chambers

    SciTech Connect

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  18. Primary intra-abdominal synovial sarcoma.

    PubMed

    Wang, Yzu-Jen; Wen, Shi-Chi; Chien, Shang-Tao; Sheu, Jin-Wen; Hsuea, Chao-Wen; Feng, Nan-Hsiung

    2006-10-01

    We report a case of primary intra-abdominal synovial sarcoma of the omentum in a 66-year-old man hospitalized for intermittent abdominal fullness for 1-2 months and tenesmus for 2 weeks. The patient had a palpable mass that was solid, hard and with well-defined thickness within his abdomen. A huge heterogeneous mass lesion over the middle abdomen that started from S2, S3 of the liver to the transverse colon was shown on abdominal computed tomography. The major cell types of the tissue mass were confirmed to be spindle and epithelial cells, which was consistent with biphasic synovial sarcoma according to pathologic and immunohistochemical findings. PMID:17098675

  19. Prediction of Residual Stress Distributions in Welded Sections of P92 Pipes with Small Diameter and Thick Wall based on 3D Finite Element Simulation

    NASA Astrophysics Data System (ADS)

    Wang, Xiaowei; Gong, Jianming; Zhao, Yanping; Wang, Yanfei

    2015-05-01

    This study used ABAQUS finite element (FE) software to investigate the residual stress distributions of P92 welded pipes in both the as-weld and post weld heat treated (PWHT) condition. Sequential coupling quasi-static thermo-mechanical in conjunction with moving double ellipsoidal heat source and an element add/remove technique to simulate deposition of new weld material, are combined in the 3D FE analysis. To validate the simulation results, the residual stresses in axial direction at the surface of pipe were measured by X-ray diffraction technique and compared with the results of FE analysis. Detailed characteristic distributions of the residual stresses are discussed. Results show that the FE model can predict the residual stress distributions satisfactorily. Highest residual stresses on the outer surface are found in the last weld bead to be deposited. And the highest tensile residual stress for the full welded section take place in heat affected zone (HAZ) near the middle thickness. Larger residual sstress can be found around the welding start point along the pipe circumference. Comparison of heat treated specimen and untreated specimen illustrates that PWHT has a strong effect on the residual stress field.

  20. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  1. Abdominal x-ray

    MedlinePlus

    An abdominal x-ray is an imaging test to look at organs and structures in the abdomen. Organs include the spleen, stomach, and intestines. When the test is done to look at the bladder and kidney structures, ...

  2. Abdominal exploration - series (image)

    MedlinePlus

    ... surgical exploration of the abdomen, also called an exploratory laparotomy, may be recommended when there is abdominal ... blunt trauma"). Diseases that may be discovered by exploratory laparotomy include: inflammation of the appendix (acute appendicitis) ...

  3. [Influences of chest deformation by upper abdominal retractor on respiratory system impedance during abdominal surgery].

    PubMed

    Oka, T; Ozawa, Y; Sato, J

    1999-02-01

    The present study was carried out to clarify the effects of chest deformation by upper abdominal retractor on respiratory system impedance during abdominal surgery. We measured the impedances of respiratory system (RS), lung, and chest wall (CW) in nine anesthetized paralyzed subjects employing a pseudorandom noise forced volume oscillation technique. These measurements were performed before and after the lifting chest wall by upper abdominal retractor. The effects of chest deformation was significant on the impedances of RS, lung, while no discernible effect was found in CW impedance. Lifting chest wall decreased RS resistance which was totally accounted for by the decrease in lung resistance, whereas the lifting did not affect reactance in either RS or lung. The mathematical modeling showed the significant lifting effect on the resistance of the parenchyma. In conclusion, change in RS mechanics produced by chest deformation by upper abdominal retractor is dominated in lung but not in CW. Among the lung mechanical components, parenchyma is the primary site of the lifting effect. PMID:10087819

  4. Gradient Echo MRI Characterization of Development of Atherosclerosis in the Abdominal Aorta in Watanabe Heritable Hyperlipidemic Rabbits

    SciTech Connect

    Wang, Yi-Xiang J. Kuribayashi, Hideto; Wagberg, Maria; Holmes, Andrew P.; Tessier, Jean J.; Waterton, John C.

    2006-08-15

    Purpose. The Watanabe Heritable Hyperlipidemic (WHHL) rabbit provides an important model of spontaneous atherosclerosis. With a strain of WHHL rabbits which do not develop abdominal aorta lumen stenosis even with advanced atherosclerosis, we studied the MRI-histology correlation, and the natural progression of atherosclerosis in the abdominal aorta. In addition, intra-reader segmentation repeatability and scan-rescan reproducibility were assessed. Methods. Two batches of female WHHL rabbits were used. The first batch of 6 rabbits was scanned at 20 weeks old. A second batch of 17 rabbits was scanned at 50 weeks old and then randomly divided into two subgroups: 8 were killed for histologic investigation; 9 were kept alive for follow-up, with repeat scanning a week later to assess scan-rescan reproducibility, and again at 73 weeks old to assess disease progression. MR images were acquired at 4.7 T using a chemical shift selective fat suppression gradient echo with a saturation band suppressing blood signal within the aortic lumen. Five slices per animal were acquired, centered around the renal artery region of the abdominal aorta, with in-plane resolution of 0.195 mm and slice thickness of 3 mm. Results. The coefficient of variation for intra-reader reproducibility for aortic wall thickness measurements was 2.5% for repeat segmentations of the same scans on the same day, but segmentations of these same scans made 8 months later showed a systematic change, suggesting that intra-reader bias as well as increased variability could compromise assessments made over time. Comparative analyses were therefore performed in one postprocessing session. The coefficient of variation for scan-rescan reproducibility for aortic wall thickness was 5.5% for nine pairs of scans acquired a week apart and segmented on the same day. Good MRI-histology correlation was obtained. The MRI-measured mean aortic wall thickness of animals at 20 weeks of age was 76% that of animals at 50 weeks of age (p < 0.001). There was a small increase in aortic wall thickness between 50 and 73 weeks of age, but this was not significant (p > 0.05). The corresponding differences in lumen cross-sectional areas at 20, 50, and 73 weeks of age were not significant. These results were consistent with in-house historical histology data on this strain of rabbits. Conclusions. High-resolution gradient echo MRI can follow disease progression in the WHHL rabbit spontaneous atherosclerosis disease model.

  5. Abdominal compartment syndrome (ACS) in a severely burned patient.

    PubMed

    Kollias, S; Stampolidis, N; Kourakos, P; Mantzari, E; Koupidis, S; Tsaousi, S; Dimitrouli, A; Atiyeh, B; Castana, O

    2015-03-31

    Abdominal compartment syndrome (ACS) occurs when increasing intra abdominal-pressure (IAP) reduces blood flow to abdominal organs. This results in impairment of pulmonary, cardiovascular, renal, hepatic, central nervous system and gastro-intestinal (gi) function, causing multiple organ dysfunction syndrome and death. The significant prognostic value of elevated intra-abdominal pressure has prompted many intensive care units to adopt measurement of this physiologic parameter as a routine vital sign in patients at risk. ACS generally occurs in patients who are critically ill due to any of a wide variety of medical and surgical conditions. it has been recently described as a rare complication of burn injury. it is fundamental to: 1) recognize IAP and ACS; 2) resuscitate effectively; and 3) prevent the development IAP-induced end-organ dysfunction and failure. We present our recent experience with one patient suffering from ACS secondary to burn injury and the physiologic results of abdominal wall escharotomy. PMID:26668555

  6. Abdominal compartment syndrome (ACS) in a severely burned patient

    PubMed Central

    kollias, S.; Stampolidis, N.; kourakos, P.; Mantzari, E.; Koupidis, S.; Tsaousi, S.; Dimitrouli, A.; Atiyeh, B.; Castana, O.

    2015-01-01

    Summary Abdominal compartment syndrome (ACS) occurs when increasing intra abdominal-pressure (IAP) reduces blood flow to abdominal organs. This results in impairment of pulmonary, cardiovascular, renal, hepatic, central nervous system and gastro-intestinal (gi) function, causing multiple organ dysfunction syndrome and death. The significant prognostic value of elevated intra-abdominal pressure has prompted many intensive care units to adopt measurement of this physiologic parameter as a routine vital sign in patients at risk. ACS generally occurs in patients who are critically ill due to any of a wide variety of medical and surgical conditions. it has been recently described as a rare complication of burn injury. it is fundamental to: 1) recognize IAP and ACS; 2) resuscitate effectively; and 3) prevent the development IAP-induced end-organ dysfunction and failure. We present our recent experience with one patient suffering from ACS secondary to burn injury and the physiologic results of abdominal wall escharotomy. PMID:26668555

  7. Appendicitis following blunt abdominal trauma.

    PubMed

    Ramesh, G; Ho, P W; Ng, K L; Jegan, T

    2002-03-01

    A young boy presented with history of abdominal trauma. History and initial clinical findings suggested a soft tissue injury. Due to increasing abdominal pain and fever, we proceeded with an exploratory laparotomy with a diagnosis of intra-abdominal injury, at which we found a perforated appendix. Appendicitis following blunt abdominal trauma needs high index of suspicion. PMID:14569731

  8. [Interest in several surgeries for serious abdominal trauma].

    PubMed

    Chosidow, D; Lesurtel, M; Sauvat, F; Paugam, C; Johanet, H; Marmuse, J P; Benhamou, G

    2000-01-01

    Abbreviated laparotomy and planned reoperation(s) is a new concept in severely injured patients with multivisceral failure by hemorrhagic shock, coagulopathy and hypothermia. The aim of an abbreviated laparotomy is to control hemorrhage, prevent digestive contamination and close the abdominal wall without tension. After a delay for reanimation during 24 to 96 hours, discovery of unknown lesions and anatomic reconstruction will be possible through planned reoperation in better conditions. Emergency reoperation for hemorrhage and abdominal hyperpression severely worsens prognosis. PMID:10921187

  9. Resolvin D1 and Lipoxin A4 Improve Alveolarization and Normalize Septal Wall Thickness in a Neonatal Murine Model of Hyperoxia-Induced Lung Injury

    PubMed Central

    Martin, Camilia R.; Zaman, Munir M.; Gilkey, Calvin; Salguero, Maria V.; Hasturk, Hatice; Kantarci, Alpdogan; Van Dyke, Thomas E.; Freedman, Steven D.

    2014-01-01

    Background The critical fatty acids Docosahexaenoic Acid (DHA) and Arachidonic Acid (AA) decline in preterm infants within the first postnatal week and are associated with neonatal morbidities, including bronchopulmonary dysplasia (BPD). DHA and AA are precursors to downstream metabolites that terminate the inflammatory response. We hypothesized that treatment with Resolvin D1 and/or Lipoxin A4 would prevent lung injury in a murine model of BPD. Objective To determine the effect of Resolvin D1 and/or Lipoxin A4 on hyperoxia-induced lung injury. Methods C57/BL6 pups were randomized at birth to Room Air, Hyperoxia (>90% oxygen), Hyperoxia + Resolvin D1, Hyperoxia + Lipoxin A4, or Hyperoxia + Resolvin D1/Lipoxin A4. Resolvin D1 and/or Lipoxin A4 (2 ng/g) were given IP on days 0, 3, 6, and 9. On day 10, mice were sacrificed and lungs collected for morphometric analyses including Mean Linear Intercept (MLI), Radial Alveolar Count (RAC), and Septal Thickness (ST); RT-PCR analyses of biomarkers of lung development and inflammation; and ELISA for TGFβ1 and TGFβ2. Result The increased ST observed with hyperoxia exposure was normalized by both Resolvin D1 and Lipoxin A4; while, hyperoxia-induced alveolar simplification was attenuated by Lipoxin A4. Relative to hyperoxia, Resolvin D1 reduced the gene expression of CXCL2 (2.9 fold), TIMP1 (6.7 fold), and PPARγ (4.8 fold). Treatment with Lipoxin A4 also led to a reduction of CXCL2 (2.4 fold) while selectively increasing TGFβ2 (2.1 fold) and Smad3 (1.58 fold). Conclusion The histologic and biochemical changes seen in hyperoxia-induced lung injury in this murine model can be reversed by the addition of DHA and AA fatty acid downstream metabolites that terminate the inflammatory pathways and modulate growth factors. These fatty acids or their metabolites may be novel therapies to prevent or treat lung injury in preterm infants. PMID:24892762

  10. Measuring Thicknesses of Wastewater Films

    NASA Technical Reports Server (NTRS)

    Schubert, F. H.; Davenport, R. J.

    1987-01-01

    Sensor determines when thickness of film of electrically conductive wastewater on rotating evaporator drum exceeds preset value. Sensor simple electrical probe that makes contact with liquid surface. Made of materials resistant to chemicals in liquid. Mounted on shaft in rotating cylinder, liquid-thickness sensor extends toward cylinder wall so tip almost touches. Sensor body accommodates probe measuring temperature of evaporated water in cylinder.

  11. Measuring wall erosion

    SciTech Connect

    Dicks, L.W.R.

    1989-10-10

    This patent describes a method for measuring decreasing thickness of the refractory lining of a high pressure, high temperature, water cooled reactor wall during operation of the reactor. It comprises: inserting a pulse-echo ultrasonic probe, which will erode at substantially the same rate as the refractory lining, into an opening in the wall of the reactor to the internal face of the refractory lining; measuring the pulse-echo signal of the probe over time so that there is an initial measure of the pulse-echo signal for the initial thickness of the lining and a current measure of the pulse-echo signal for the current thickness of the lining; calculating the thickness of the lining of the wall from the thickness measured at the initial time and the thickness measured at the current time; measuring at least one of; a temperature gradient which occurs in the probe over the time of operation; and a sound velocity change as a function of the temperature; adjusting the calculated thickness of the lining of the wall; and providing an adjusted calculated thickness of the lining of the wall.

  12. [Abdominal actinomycosis: four cases].

    PubMed

    Ghannouchi Jaafoura, N; Kaabia, N; Khalifa, M; Ben Jazia, I; Hachfi, W; Braham, A; Letaief, A; Bahri, F

    2008-12-01

    The abdominal actinomycosis (AA) is a rare and often unrecognised suppurative chronic illness. It is caused by an anaerobic Gram positive bacteria, Actinomyces israelii. Abdominal actinomycosis is responsible for pseudotumoral syndrome often leading, to a large and mutilating surgery whereas a prolonged treatment by antibiotics would have permitted to cure the disease. The diagnosis is obtained generally from anatomopathologic exam. We report four cases of abdominal actinomycosis being revealed by a pseudotumoral syndrome. The diagnosis was only made after surgery. In spite of an active treatment by antibiotics during several months, two of our patients had a relapse of the infectious process. These four observations confirm the diagnostic and therapeutic difficulties previously reported by other authors. PMID:19180833

  13. Abdominal Vascular Catastrophes.

    PubMed

    Singh, Manpreet; Koyfman, Alex; Martinez, Joseph P

    2016-05-01

    Abdominal vascular catastrophes are among the most challenging and time sensitive for emergency practitioners to recognize. Mesenteric ischemia remains a highly lethal entity for which the history and physical examination can be misleading. Laboratory tests are often unhelpful, and appropriate imaging must be quickly obtained. A multidisciplinary approach is required to have a positive impact on mortality rates. Ruptured abdominal aortic aneurysm likewise may present in a cryptic fashion. A specific type of ruptured aneurysm, the aortoenteric fistula, often masquerades as the more common routine gastrointestinal bleed. The astute clinician recognizes that this is a more lethal variant of gastrointestinal hemorrhage. PMID:27133247

  14. The Relationship of Abdominal Muscles Balance and Body Balance

    PubMed Central

    Seo, Dong-Kwon; Kim, Ji-Seon; Lee, Dong-Yeop; Kwon, Oh-Sung; Lee, Sang-Sook; Kim, Jee-Hee

    2013-01-01

    This study aimed to identify what impact the thickness differences between the leftside and rightside transversus abdominis (TrA), internal obliquus (IO) and external obliquus (EO) have on balance ability in the abdominal drawing-in maneuver (ADIM) and resting postures. [Subjects and Methods] In this study, 41 young adults were asked to adopt a resting posture and to perform ADIM. The thicknesses of the abdominal muscles (TrA, IO, EO) were measured using ultrasound imaging, Then balance ability was measured, so that a comparative analysis could be carried out. [Results] According to the results, the thicknesses of TrA and IO very significantly increased when ADIM was performed. The changes in thickness of the muscles on the left and right sides showed no significant correlations with balance ability. [Conclusion] According to the study results, the difference in thickness between the left and right side muscles in a normal person is small (symmetric), and the differences in the thickness of TrA and IO on the left and right side reduced when the ADIM, which is a re-education method for abdominal muscles was performed. Therefore, we consider that the ADIM should be used in future clinical trials to induce symmetric contraction of the abdominal muscles. Also, the correlation results of muscle balance and body balance can be used as empirical data. PMID:24259848

  15. The relationship of abdominal muscles balance and body balance.

    PubMed

    Seo, Dong-Kwon; Kim, Ji-Seon; Lee, Dong-Yeop; Kwon, Oh-Sung; Lee, Sang-Sook; Kim, Jee-Hee

    2013-07-01

    This study aimed to identify what impact the thickness differences between the leftside and rightside transversus abdominis (TrA), internal obliquus (IO) and external obliquus (EO) have on balance ability in the abdominal drawing-in maneuver (ADIM) and resting postures. [Subjects and Methods] In this study, 41 young adults were asked to adopt a resting posture and to perform ADIM. The thicknesses of the abdominal muscles (TrA, IO, EO) were measured using ultrasound imaging, Then balance ability was measured, so that a comparative analysis could be carried out. [Results] According to the results, the thicknesses of TrA and IO very significantly increased when ADIM was performed. The changes in thickness of the muscles on the left and right sides showed no significant correlations with balance ability. [Conclusion] According to the study results, the difference in thickness between the left and right side muscles in a normal person is small (symmetric), and the differences in the thickness of TrA and IO on the left and right side reduced when the ADIM, which is a re-education method for abdominal muscles was performed. Therefore, we consider that the ADIM should be used in future clinical trials to induce symmetric contraction of the abdominal muscles. Also, the correlation results of muscle balance and body balance can be used as empirical data. PMID:24259848

  16. Thin Wall Iron Castings

    SciTech Connect

    J.F. Cuttino; D.M. Stefanescu; T.S. Piwonka

    2001-10-31

    Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

  17. In vivo performance of antibiotic embedded electrospun PCL membranes for prevention of abdominal adhesions.

    PubMed

    Bölgen, N; Vargel, I; Korkusuz, P; Menceloğlu, Y Z; Pişkin, E

    2007-05-01

    The aim of this study was to prepare nonwoven materials from poly(epsilon-caprolactone) (PCL) and their antibiotic containing forms by electrospinning, so as to prevent postsurgery induced abdominal adhesions in rats. epsilon-Caprolactone was first polymerized by ring-opening polymerization, and then it was processed into matrices composed of nanofibers by electrospinning. A model antibiotic (Biteral) was embedded within a group of PCL membranes. In the rat model, defects on the abdominal walls in the peritoneum were made to induce adhesion. The plain or antibiotic embedded PCL membranes were implanted on the right side of the abdominal wall. No membrane implantation was made on the left side of the abdominal wall that served as control. Macroscopical and histological evaluations showed that using these barriers reduces the extent, type, and tenacity of adhesion. The antibiotic embedded membranes significantly eliminated postsurgery abdominal adhesions, and also improved healing. PMID:17041925

  18. LATERAL ABDOMINAL MUSCLE SYMMETRY IN COLLEGIATE SINGLE-SIDED ROWERS

    PubMed Central

    Gill, Norman W.; Mason, Beth E.; Gerber, J. Parry

    2012-01-01

    Purpose/Background: Although side to side symmetry of lateral abdominal muscle thickness has been established in healthy individuals, it is unknown whether abdominal muscle symmetry exists in athletes with asymmetrical physiological demands, such as those of single-sided rowers. The purpose of this study was to examine the oarside versus the non-oarside lateral abdominal musculature thickness in collegiate single-sided rowers, as measured by ultrasound imaging (USI). Methods: The study was a prospective, cross-sectional, observational design. Thirty collegiate crew team members (17 males, 13 females, age 19.8±1.2 years) characterized as single-sided rowers participated. Resting muscle thickness measurements of the transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) muscles were obtained via USI. Comparisons of absolute and relative muscle thickness between oarside and non-oarside were performed using paired t-tests. Potential differences based on gender, rowing experience, and history of low back pain were investigated using mixed model analysis of variance. Results: There were no clinically significant differences in absolute or relative thickness of the TrA, IO or EO on the oarside versus the non-oarside. There were no significant side to side differences in the relative muscle thickness of the TrA, IO or EO based on gender, rowing experience, or history of low back pain. Conclusions: In this sample of single-sided rowing athletes, no clinically significant side to side differences in lateral abdominal muscle thickness were observed. Despite the asymmetrical functional demands of single-sided rowers in this study, thickness of the lateral abdominal muscles was symmetric. Level of Evidence: 4 PMID:22319677

  19. Intra-abdominal sepsis.

    PubMed

    Holliday, R L

    1976-01-01

    Intra-abdominal sepsis remains one of the major challenges to the surgeon. With a proper appreciation of the bacteriology and pathophysiology involved and an awareness of new diagnostic and therapeutic modalities, hopefully, mortality and morbidity rates can be reduced. PMID:1048948

  20. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final recommendation ...

  1. JAMA Patient Page: Abdominal Hernia

    MedlinePlus

    ... The Journal of the American Medical Association Abdominal Hernia Common abdominal hernias A HERNIA DEVELOPS WHEN A WEAKNESS THAT FORMS IN THE ... through it. Among the most common are umbilical hernias that occur at the navel and inguinal hernias ...

  2. A Rapidly Growing Abdominal Mass: Desmoid Tumor in Pregnancy

    PubMed Central

    Leon, Mateo G.; Moussa, Hind N.; Movahedian, Malahat; Viteri, Oscar A.; Longo, Monica; Sibai, Baha M.

    2014-01-01

    Background Desmoid tumors are benign soft tissue tumors that locally invade adjacent tissue. There is a paucity of reports describing the rapid growth of these tumors during pregnancy. Case A giant desmoid tumor arising from the left abdominal wall of a young female patient with rapid growth during pregnancy is described. Preoperative evaluation included ultrasonography and magnetic resonance imaging. Decision made by a multidisciplinary team was not to intervene before birth, and abdominal delivery at term was accomplished. Conclusion Desmoid tumors should be part of the differential diagnosis in an abdominal wall tumor of rapid growth during pregnancy. Future studies are needed for better understanding of the pathogenesis, diagnosis, and treatment of desmoid tumors in pregnant women. PMID:26199790

  3. Abdominal actinomycosis with multiple myeloma: A case report

    PubMed Central

    ERCOLAK, VEHBI; PAYDAS, SEMRA; ERGIN, MELEK; ATES, BERNA T.; DUMAN, BERNA B.; GUNALDI, MERAL; AFSAR, CIGDEM U.

    2014-01-01

    Actinomycosis is a chronic suppurative infection, for which immune suppression is a predisposing factor. In unusual cases, this disease may present as an abdominal wall involvement simulating a soft tissue tumor as seen in the present case. The presented patient had no signs of trauma or surgical approach and the pathology was considered to be a primary abdominal wall actinomycosis. Preoperative diagnosis is difficult due to the nonspecific nature of clinical presentation, radiographic and laboratory findings. Surgery combined with antibiotic treatment is a curative approach for this relatively rare infection. Surgeons must be aware of this disease in order to ensure correct diagnosis and to prevent performing any unnecessary procedures. The present study describes a case of abdominal actinomycosis with multiple myeloma, together with a review of important points related to this disease. PMID:25202429

  4. Localizing gravity on exotic thick 3-branes

    SciTech Connect

    Castillo-Felisola, Oscar; Melfo, Alejandra; Pantoja, Nelson; Ramirez, Alba

    2004-11-15

    We consider localization of gravity on thick branes with a nontrivial structure. Double walls that generalize the thick Randall-Sundrum solution, and asymmetric walls that arise from a Z{sub 2} symmetric scalar potential, are considered. We present a new asymmetric solution: a thick brane interpolating between two AdS{sub 5} spacetimes with different cosmological constants, which can be derived from a 'fake supergravity' superpotential, and show that it is possible to confine gravity on such branes.

  5. Thoraco-abdominal Ectopia Cordis in Southwest Cameroon

    PubMed Central

    Chishugi, John B; Franke, Trixy J

    2014-01-01

    Ectopia cordis is a rare congenital defect where the heart is completely displaced outside the chest wall. Cantrell's pentalogy is an embryologic anomaly with five classic midline deficiencies often associated with ectopia cordis. Here we present a case of thoraco-abdominal ectopia cordis, brief literature review, and possible implications for changes in antenatal care. PMID:25404984

  6. Thoraco-abdominal ectopia cordis in southwest Cameroon.

    PubMed

    Chishugi, John B; Franke, Trixy J

    2014-01-01

    Ectopia cordis is a rare congenital defect where the heart is completely displaced outside the chest wall. Cantrell's pentalogy is an embryologic anomaly with five classic midline deficiencies often associated with ectopia cordis. Here we present a case of thoraco-abdominal ectopia cordis, brief literature review, and possible implications for changes in antenatal care. PMID:25404984

  7. A longitudinal comparison of hemodynamics and intraluminal thrombus deposition in abdominal aortic aneurysms

    PubMed Central

    Arzani, Amirhossein; Suh, Ga-Young; Dalman, Ronald L.

    2014-01-01

    Abdominal aortic aneurysm (AAA) is often accompanied by in traluminal thrombus (ILT), which complicates AAA progression and risk of rupture. Patient-specific computational fluid dynamics modeling of 10 small human AAA was performed to investigate relations between hemodynamics and ILT progression. The patients were imaged using magnetic resonance twice in a 2- to 3-yr interval. Wall content data were obtained by a planar T1-weighted fast spin echo black-blood scan, which enabled quantification of thrombus thickness at midaneurysm location during baseline and followup. Computational simulations with patient-specific geometry and boundary conditions were performed to quantify the hemodynamic parameters of time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and mean exposure time at baseline. Spatially resolved quantifications of the change in ILT thickness were compared with the different hemodynamic parameters. Regions of low OSI had the strongest correlation with ILT growth and demonstrated a statistically significant correlation coefficient. Prominent regions of high OSI (>0.4) and low TAWSS (<1 dyn/cm2) did not appear to coincide with locations of thrombus deposition. PMID:25326533

  8. The Abdominal Circulatory Pump

    PubMed Central

    Aliverti, Andrea; Bovio, Dario; Fullin, Irene; Dellacà, Raffaele L.; Lo Mauro, Antonella; Pedotti, Antonio; Macklem, Peter T.

    2009-01-01

    Blood in the splanchnic vasculature can be transferred to the extremities. We quantified such blood shifts in normal subjects by measuring trunk volume by optoelectronic plethysmography, simultaneously with changes in body volume by whole body plethysmography during contractions of the diaphragm and abdominal muscles. Trunk volume changes with blood shifts, but body volume does not so that the blood volume shifted between trunk and extremities (Vbs) is the difference between changes in trunk and body volume. This is so because both trunk and body volume change identically with breathing and gas expansion or compression. During tidal breathing Vbs was 50–75 ml with an ejection fraction of 4–6% and an output of 750–1500 ml/min. Step increases in abdominal pressure resulted in rapid emptying presumably from the liver with a time constant of 0.61±0.1SE sec. followed by slower flow from non-hepatic viscera. The filling time constant was 0.57±0.09SE sec. Splanchnic emptying shifted up to 650 ml blood. With emptying, the increased hepatic vein flow increases the blood pressure at its entry into the inferior vena cava (IVC) and abolishes the pressure gradient producing flow between the femoral vein and the IVC inducing blood pooling in the legs. The findings are important for exercise because the larger the Vbs the greater the perfusion of locomotor muscles. During asystolic cardiac arrest we calculate that appropriate timing of abdominal compression could produce an output of 6 L/min. so that the abdominal circulatory pump might act as an auxiliary heart. PMID:19440240

  9. Novel 3D ultrasound image-based biomarkers based on a feature selection from a 2D standardized vessel wall thickness map: a tool for sensitive assessment of therapies for carotid atherosclerosis

    NASA Astrophysics Data System (ADS)

    Chiu, Bernard; Li, Bing; Chow, Tommy W. S.

    2013-09-01

    With the advent of new therapies and management strategies for carotid atherosclerosis, there is a parallel need for measurement tools or biomarkers to evaluate the efficacy of these new strategies. 3D ultrasound has been shown to provide reproducible measurements of plaque area/volume and vessel wall volume. However, since carotid atherosclerosis is a focal disease that predominantly occurs at bifurcations, biomarkers based on local plaque change may be more sensitive than global volumetric measurements in demonstrating efficacy of new therapies. The ultimate goal of this paper is to develop a biomarker that is based on the local distribution of vessel-wall-plus-plaque thickness change (VWT-Change) that has occurred during the course of a clinical study. To allow comparison between different treatment groups, the VWT-Change distribution of each subject must first be mapped to a standardized domain. In this study, we developed a technique to map the 3D VWT-Change distribution to a 2D standardized template. We then applied a feature selection technique to identify regions on the 2D standardized map on which subjects in different treatment groups exhibit greater difference in VWT-Change. The proposed algorithm was applied to analyse the VWT-Change of 20 subjects in a placebo-controlled study of the effect of atorvastatin (Lipitor). The average VWT-Change for each subject was computed (i) over all points in the 2D map and (ii) over feature points only. For the average computed over all points, 97 subjects per group would be required to detect an effect size of 25% that of atorvastatin in a six-month study. The sample size is reduced to 25 subjects if the average were computed over feature points only. The introduction of this sensitive quantification technique for carotid atherosclerosis progression/regression would allow many proof-of-principle studies to be performed before a more costly and longer study involving a larger population is held to confirm the treatment efficacy.

  10. Superconducting magnetoresistance effect observed in Co/Nb/Co trilayers under a parallel magnetic field: The importance of matching the width of magnetic domain walls of the Co layers with the thickness of the Nb interlayer

    NASA Astrophysics Data System (ADS)

    Aristomenopoulou, E.; Stamopoulos, D.

    2015-08-01

    Magnetoresistance effects observed in ferromagnet/superconductor (FM/SC) hybrids, FM/SC bilayers (BLs) and FM/SC/FM trilayers (TLs), have attracted much interest. Here, we focus on the stray-fields-based superconducting magnetoresistance effect (sMRE) observed in Co(dCo)/Nb(dNb)/Co(dCo) TLs with sufficiently thick Co outer layers so that out-of-plane magnetic domains (MDs) and MDs walls (MDWs) emerge all over their surface when subjected to a parallel external magnetic field, Hex, equal to the coercive field, Hc. To explore the conditions necessary for maximization of the sMRE, we focus on the different kinds of the stray dipolar fields, Hdip, that emerge at the interior of the out-of-plane MDs and at the boundaries of MDWs; these have a different inherent tendency to create straight and semi-loop vortices, respectively. In the recent literature, the creation of straight and semi-loop vortices has been addressed at some extent both theoretically [Laiho et al., Phys. Rev. B 67, 144522 (2003)] and experimentally [Bobba et al., Phys. Rev. B 89, 214502 (2014)] for the case of FM/SC BLs. Here, we address these issues in FM/SC/FM TLs in connection to the sMRE. Specifically, we focus on an experimental finding reported recently [D. Stamopoulos and E. Aristomenopoulou, J. Appl. Phys. 116, 233908 (2014)]; strong magnetostatic coupling of the FM outer layers is accompanied by an intense sMRE in TLs in which the thickness of the SC interlayer, dSC, matches the width of MDWs, DMDWs. To investigate this finding, we employ simulations-modeling and energy-considerations and propose two quantitative criteria that facilitate the creation of straight vortices over semi-loop ones. The first focuses on the maximization of the stray Hdip that occur at the interior of the out-of-plane MDs. The second enables the estimation of a crossover between the preferable creation of one kind of vortices over the other. Both criteria respond well, when tested against experimental results. These generic criteria on the interference between dSC and DMDWs can assist the design of cryogenic devices based on FM/SC/FM TLs.

  11. Abdominal breathing manoeuvre reduces passive drag acting on gliding swimmers.

    PubMed

    Maruyama, Yusuke; Yanai, Toshimasa

    2015-01-01

    The purpose of this study was to test the hypothesis that the passive drag acting on a gliding swimmer is reduced if the swimmer adopts an abdominal breathing manoeuvre (expanding the abdominal wall) rather than chest breathing manoeuvre (expanding the rib cage). Eleven male participants participated in this study. A specialised towing machine was used to tow each participant with tension set at various magnitudes and to record time series data of towing velocity. Participants were asked to inhale air by expanding the abdominal wall or the rib cage and to maintain the same body configuration throughout gliding. The steady-state velocity was measured and the coefficient of drag was calculated for each towing trial to compare between the breathing manoeuvres. The results showed that the towing velocity was increased by 0.02 m/s with a towing force of 34.3 N and by 0.06 m/s with a towing force of 98.1 N. The coefficient of drag was reduced by 5% with the abdominal breathing manoeuvre, which was found to be statistically significant (p < 0.05). These results indicate that adopting the abdominal breathing manoeuvre during gliding reduces the passive drag and the hypothesis was supported. PMID:26715235

  12. Abdominal imaging: An introduction

    SciTech Connect

    Frick, M.P.; Feinberg, S.B.

    1986-01-01

    This nine-chapter book gives an overview of the integrated approach to abdominal imaging. Chapter 1 provides an introduction to the physics used in medical imaging; chapter 2 is on the selection of imaging modalities. These are followed by four chapters that deal, respectively, with plain radiography, computed tomographic scanning, sonography, and nuclear imaging, as applied to the abdomen. Two chapters then cover contrast material-enhanced studies of the gastrointestinal (GI) tract: one focusing on technical considerations; the other, on radiologic study of disease processes. The final chapter is a brief account of different interventional procedures.

  13. Abdominal Superficial Subcutaneous Fat

    PubMed Central

    Golan, Rachel; Shelef, Ilan; Rudich, Assaf; Gepner, Yftach; Shemesh, Elad; Chassidim, Yoash; Harman-Boehm, Ilana; Henkin, Yaakov; Schwarzfuchs, Dan; Ben Avraham, Sivan; Witkow, Shula; Liberty, Idit F.; Tangi-Rosental, Osnat; Sarusi, Benjamin; Stampfer, Meir J.; Shai, Iris

    2012-01-01

    OBJECTIVE Unlike visceral adipose tissue (VAT), the association between subcutaneous adipose tissue (SAT) and obesity-related morbidity is controversial. In patients with type 2 diabetes, we assessed whether this variability can be explained by a putative favorable, distinct association between abdominal superficial SAT (SSAT) (absolute amount or its proportion) and cardiometabolic parameters. RESEARCH DESIGN AND METHODS We performed abdominal magnetic resonance imaging (MRI) in 73 patients with diabetes (mean age 58 years, 83% were men) and cross-sectionally analyzed fat distribution at S1-L5, L5-L4, and L3-L2 levels. Patients completed food frequency questionnaires, and subgroups had 24-h ambulatory blood pressure monitoring and 24-h ambulatory electrocardiography. RESULTS Women had higher %SSAT (37 vs. 23% in men; P < 0.001) despite a similar mean waist circumference. Fasting plasma glucose (P = 0.046) and HbA1c (P = 0.006) were both lower with increased tertile of absolute SSAT. In regression models adjusted for age, waist circumference, and classes of medical treatments used in this patient population, increased %SSAT was significantly associated with decreased HbA1c (β = −0.317; P = 0.013), decreased daytime ambulatory blood pressure (β = −0.426; P = 0.008), and increased HDL cholesterol (β = 0.257; P = 0.042). In contrast, increased percent of deep SAT (DSAT) was associated with increased HbA1c (β = 0.266; P = 0.040) and poorer heart rate variability parameters (P = 0.030). Although total fat and energy intake were not correlated with fat tissue distribution, increased intake of trans fat tended to be associated with total SAT (r = 0.228; P = 0.05) and DSAT (r = 0.20; P = 0.093), but not with SSAT. CONCLUSIONS Abdominal SAT is composed of two subdepots that associate differently with cardiometabolic parameters. Higher absolute and relative distribution of fat in abdominal SSAT may signify beneficial cardiometabolic effects in patients with type 2 diabetes. PMID:22344612

  14. Functional abdominal bloating.

    PubMed

    Sullivan, S N

    1994-07-01

    Ten to 25% of healthy persons have bloating at some time or other. It is very common in those with the irritable bowel syndrome, constipation, or anorexia nervosa. Although the cause of functional bloating remains unknown, old explanations such as a low diaphragm, exaggerated lumbar lordosis, and psychiatric problems have been disproved. New suggestions on its etiology include recent weight gain, weak abdominal muscles, and retained fluid in loops of small intestine. No treatment is of proven benefit, but treatment by weight loss, exercise, and prokinetics should be studied. PMID:7930428

  15. Recurrent abdominal pain.

    PubMed

    Stickler, G B; Murphy, D B

    1979-05-01

    A long-term follow-up study (minimum of five years) of 161 children with recurrent abdominal pain disclosed that three had organic disease and that was missed--inflammatory bowel disease. Anorexia nervosa developed in one patient. Three fourths of the patients recovered from the initial symptom; most recovered within a few weeks; but some patients continued to have complaints for a number of years. Approximately 20% of patients underwent additional surgical or medical treatments of doubtful necessity. In 18% of patients, other psychosomatic symptoms developed. PMID:433872

  16. Lower Abdominal Pain.

    PubMed

    Carlberg, David J; Lee, Stephen D; Dubin, Jeffrey S

    2016-05-01

    Although most frequently presenting with lower abdominal pain, appendicitis, colitis, and diverticulitis can cause pain throughout the abdomen and can cause peritoneal and retroperitoneal symptoms. Evaluation and management of lower intestinal disease requires a nuanced approach by the emergency physician, sometimes requiring computed tomography, ultrasonography, MRI, layered imaging, shared decision making, serial examination, and/or close follow-up. Once a presumed or confirmed diagnosis is made, appropriate treatment is initiated, and may include surgery, antibiotics, and/or steroids. Appendicitis patients should be admitted. Diverticulitis and inflammatory bowel disease can frequently be managed on an outpatient basis, but may require admission and surgical consultation. PMID:27133242

  17. Mouse bladder wall injection.

    PubMed

    Fu, Chi-Ling; Apelo, Charity A; Torres, Baldemar; Thai, Kim H; Hsieh, Michael H

    2011-01-01

    Mouse bladder wall injection is a useful technique to orthotopically study bladder phenomena, including stem cell, smooth muscle, and cancer biology. Before starting injections, the surgical area must be cleaned with soap and water and antiseptic solution. Surgical equipment must be sterilized before use and between each animal. Each mouse is placed under inhaled isoflurane anesthesia (2-5% for induction, 1-3% for maintenance) and its bladder exposed by making a midline abdominal incision with scissors. If the bladder is full, it is partially decompressed by gentle squeezing between two fingers. The cell suspension of interest is intramurally injected into the wall of the bladder dome using a 29 or 30 gauge needle and 1 cc or smaller syringe. The wound is then closed using wound clips and the mouse allowed to recover on a warming pad. Bladder wall injection is a delicate microsurgical technique that can be mastered with practice. PMID:21775962

  18. Biochemomechanics of intraluminal thrombus in abdominal aortic aneurysms.

    PubMed

    Wilson, J S; Virag, L; Di Achille, P; Karsaj, I; Humphrey, J D

    2013-02-01

    Most computational models of abdominal aortic aneurysms address either the hemodynamics within the lesion or the mechanics of the wall. More recently, however, some models have appropriately begun to account for the evolving mechanics of the wall in response to the changing hemodynamic loads. Collectively, this large body of work has provided tremendous insight into this life-threatening condition and has provided important guidance for current research. Nevertheless, there has yet to be a comprehensive model that addresses the mechanobiology, biochemistry, and biomechanics of thrombus-laden abdominal aortic aneurysms. That is, there is a pressing need to include effects of the hemodynamics on both the development of the nearly ubiquitous intraluminal thrombus and the evolving mechanics of the wall, which depends in part on biochemical effects of the adjacent thrombus. Indeed, there is increasing evidence that intraluminal thrombus in abdominal aortic aneurysms is biologically active and should not be treated as homogeneous inert material. In this review paper, we bring together diverse findings from the literature to encourage next generation models that account for the biochemomechanics of growth and remodeling in patient-specific, thrombus-laden abdominal aortic aneurysms. PMID:23445056

  19. Moisture Research - Optimizing Wall Assemblies

    SciTech Connect

    Arena, Lois; Mantha, Pallavi

    2013-05-01

    In this project, the Consortium for Advanced Residential Buildings (CARB) team evaluated several different configurations of wall assemblies to determine the accuracy of moisture modeling and make recommendations to ensure durable, efficient assemblies. WUFI and THERM were used to model the hygrothermal and heat transfer characteristics of these walls. Wall assemblies evaluated included code minimum walls using spray foam insulation and fiberglass batts, high R-value walls at least 12 in. thick (R-40 and R-60 assemblies), and brick walls with interior insulation.

  20. [Pathophysiology of abdominal pain].

    PubMed

    Curatolo, Michele

    2011-08-01

    Abdominal pain can be induced by stimulation of visceral nociceptors. Activation of nociceptors usually requires previous sensitization by pathological events, such as inflammation, ischemia or acidosis. Although abdominal pain can obviously be caused by pathology of a visceral structure, clinicians frequently observe that such a pathology explains only part of the pain complaints. Occasionally, there is lack of objective signs of visceral lesions. There is clear evidence that pain states are associated with profound changes of the central processing of the sensory input. The main consequences of such alterations for patients are twofold: 1) a central sensitization, i.e. an increased excitability of the central nervous system; 2) an alteration of the endogenous pain modulation, which under normal conditions inhibits the processing of nociceptive signals in the central nervous system. Both phenomena lead to a spread of pain to other body regions and an amplification of the pain perception. The interactions between visceral pathology and alterations of the central pain processes represent an at least partial explanation for the discrepancy between objective signs of peripheral lesions and severity of the symptoms. Today, both central hypersensitivity and alteration in endogenous pain modulation can be measured in clinical practice. This information can be used to provide the patients with an explanatory model for their pain. Furthermore, first data suggest that alterations in central pain processing may represent negative prognostic factors. A better understanding of the individual pathophysiology may allow in the future the development of individual therapeutic strategies. PMID:21796591

  1. How I Manage Abdominal Injuries.

    ERIC Educational Resources Information Center

    Haycock, Christine E.

    1986-01-01

    In sports, abdominal injuries occur most frequently in cycling, horseback riding, and skiing. Most involve children, not adults. Any athlete sustaining a severe blow to the abdomen should be examined. Guidelines are provided for recognizing and treating injuries to the abdominal muscles, kidneys, spleen, and liver. (Author/MT)

  2. Abdominal aortic aneurysm repair - open

    MedlinePlus

    Open abdominal aortic aneurysm repair is surgery to fix a widened part in your aorta. This is called an aneurysm. The ... Open surgery to repair an abdominal aortic aneurysm is sometimes ... is bleeding inside your body from the aneurysm. You may have an ...

  3. Adventitial Vasa Vasorum Arteriosclerosis in Abdominal Aortic Aneurysm

    PubMed Central

    Sasaki, Takeshi; Hayasaka, Takahiro; Goto-Inoue, Naoko; Onoue, Kenji; Ikegami, Koji; Morita, Yoshifumi; Yamamoto, Naoto; Mano, Yuuki; Sano, Masaki; Saito, Takaaki; Sato, Kohji; Konno, Hiroyuki; Setou, Mitsutoshi; Unno, Naoki

    2013-01-01

    Abdominal aortic aneurysm (AAA) is a common disease among elderly individuals. However, the precise pathophysiology of AAA remains unknown. In AAA, an intraluminal thrombus prevents luminal perfusion of oxygen, allowing only the adventitial vaso vasorum (VV) to deliver oxygen and nutrients to the aortic wall. In this study, we examined changes in the adventitial VV wall in AAA to clarify the histopathological mechanisms underlying AAA. We found marked intimal hyperplasia of the adventitial VV in the AAA sac; further, immunohistological studies revealed proliferation of smooth muscle cells, which caused luminal stenosis of the VV. We also found decreased HemeB signals in the aortic wall of the sac as compared with those in the aortic wall of the neck region in AAA. The stenosis of adventitial VV in the AAA sac and the malperfusion of the aortic wall observed in the present study are new aspects of AAA pathology that are expected to enhance our understanding of this disease. PMID:23460850

  4. Ultrasonic thickness measuring and imaging system and method

    DOEpatents

    Bylenok, Paul J.; Patmos, William M.; Wagner, Thomas A.; Martin, Francis H.

    1992-01-01

    An ultrasonic thickness measuring and imaging system uses an ultrasonic fsed beam probe for measuring thickness of an object, such as a wall of a tube, a computer for controlling movement of the probe in a scanning pattern within the tube and processing an analog signal produced by the probe which is proportional to the tube wall thickness in the scanning pattern, and a line scan recorder for producing a record of the tube wall thicknesses measured by the probe in the scanning pattern. The probe is moved in the scanning pattern to sequentially scan circumferentially the interior tube wall at spaced apart adjacent axial locations. The computer processes the analog signal by converting it to a digital signal and then quantifies the digital signal into a multiplicity of thickness points with each falling in one of a plurality of thickness ranges corresponding to one of a plurality of shades of grey. From the multiplicity of quantified thickness points, a line scan recorder connected to the computer generates a pictorial map of tube wall thicknesses with each quantified thickness point thus being obtained from a minute area, e.g. 0.010 inch by 0.010 inch, of tube wall and representing one pixel of the pictorial map. In the pictorial map of tube wall thicknesses, the pixels represent different wall thicknesses having different shades of grey.

  5. Ultrasonic thickness measuring and imaging system and method

    DOEpatents

    Bylenok, Paul J.; Patmos, William M.; Wagner, Thomas A.; Martin, Francis H.

    1992-08-04

    An ultrasonic thickness measuring and imaging system uses an ultrasonic fsed beam probe for measuring thickness of an object, such as a wall of a tube, a computer for controlling movement of the probe in a scanning pattern within the tube and processing an analog signal produced by the probe which is proportional to the tube wall thickness in the scanning pattern, and a line scan recorder for producing a record of the tube wall thicknesses measured by the probe in the scanning pattern. The probe is moved in the scanning pattern to sequentially scan circumferentially the interior tube wall at spaced apart adjacent axial locations. The computer processes the analog signal by converting it to a digital signal and then quantifies the digital signal into a multiplicity of thickness points with each falling in one of a plurality of thickness ranges corresponding to one of a plurality of shades of grey. From the multiplicity of quantified thickness points, a line scan recorder connected to the computer generates a pictorial map of tube wall thicknesses with each quantified thickness point thus being obtained from a minute area, e.g. 0.010 inch by 0.010 inch, of tube wall and representing one pixel of the pictorial map. In the pictorial map of tube wall thicknesses, the pixels represent different wall thicknesses having different shades of grey.

  6. 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.

  7. Hyperthermia in the treatment of recurrent abdominal desmoid tumor.

    PubMed

    Ishikawa, Hiroto; Hirakawa, Hiroaki; Takahashi, Kenjiro; Kawashima, Yusuke; Yoshida, Takeshi; Isobe, Taro; Matono, Satoru; Kawahara, Ryuichi; Hisaka, Toru; Horiuchi, Hiroyuki; Nakayama, Masamichi; Okabe, Yoshinobu; Yamatsu, Yoshiyasu; Yano, Hirohisa; Akagi, Yoshito

    2014-11-01

    The most suitable management of recurrent abdominal desmoid tumor is still unclear. A case of recurrent huge abdominal desmoid tumor successfully treated by hyperthermia therapy is described. A 63-year-old man was operated upon for desmoid tumor in the retroperitoneum involving pancreas, posterior wall of the stomach and transverse mesocolon in 2007. In 2008, the tumor recurred and could not be resected because of the patient refused the operation. Several therapies using tamoxifen, anastrozole, imatinib mesylate and radiotherapy were all ineffective. The tumor grew bigger and bigger during a treatment period. Finally, hyperthermia treatment was applied to the tumor. The size of the recurrent desmoid tumor reduced 75% by hyperthermia treatment for 46-month. Base on this experience, we recommend hyperthermia as the treatment for patients with recurrent abdominal desmoid tumor that several therapeutic strategies did not achieve a remarkable response. PMID:25731565

  8. MIR wall surveyor

    SciTech Connect

    Lehman, S K

    1998-08-01

    This report addresses the problem of determining the layer thickness of a wall probed with a monostatic, hand-held implementation of Lawrence Livermore National Laboratory's Micropower Impulse Radar (MIR). Our goal is to locate the layers of the wall, and measure its overall thickness. The physical constraints require the device to be held fixed or swept rapidly over the wall. Thus an insufficient amount of backscattered data are collected to use diffraction tomographic [3] techniques to form images. The problem is therefore one of determining the wall layers from a set of time series reflection data. We develop two channel signal processing algorithms to determine the location of the layers of a wall, using as inputs the time series returned from the wall and the incident pulse. We study the problem using a finite difference time domain (FDTD) computer code to simulate the electromagnetic propagation within and scattering from a wall probed with five pulses. We use the results to develop and test signal processing procedures for locating the individual layers. We study two classes of algorithms: a deconvolution approach to determine a layered impulse response, and a correlation approach. After testing the algorithms on the FDTD results, we down-select to a suitable method.

  9. Abdominal aortic aneurysm demonstrated on renal scintigraphy.

    PubMed

    Phisitkul, Sorot; Brian, Susan; Rakvit, Ariwan; Jenkins, Leigh A; Bohannon, W Todd; Harris, Jennifer; Tsikouris, James; Silva, Michael B; Meyerrose, Gary E

    2003-08-01

    A 74-year-old hypertensive woman presented with abdominal discomfort and a pulsatile abdominal mass. Anterior abdominal angiography during cardiac blood pool, and renal scintigraphic imaging demonstrated a large abdominal aortic aneurysm. 1, 2 Before endovascular repair with an aortoiliac endograft, the abdominal aneurysm measured 7.5 x 7.0 cm on abdominal computed tomography. This study demonstrates that a suspected abdominal aortic aneurysm can be confirmed using the addition of anterior abdominal imaging with normal posterior imaging at the time of renal scintigraphy. PMID:12897671

  10. Pulsatile blood flow in Abdominal Aortic Aneurysms

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Lasheras, Juan C.; Singel, Soeren; Varga, Chris

    2001-11-01

    We discuss the results of combined in-vitro laboratory measurements and clinical observations aimed at determining the effect that the unsteady wall shear stresses and the pressure may have on the growth and eventual rupturing of an Abdominal Aortic Aneurysm (AAA), a permanent bulging-like dilatation occurring near the aortic bifurcation. In recent years, new non-invasive techniques, such as stenting, have been used to treat these AAAs. However, the development of these implants, aimed at stopping the growth of the aneurysm, has been hampered by the lack of understanding of the effect that the hemodynamic forces have on the growth mechanism. Since current in-vivo measuring techniques lack the precision and the necessary resolution, we have performed measurements of the pressure and shear stresses in laboratory models. The models of the AAA were obtained from high resolution three-dimensional CAT/SCANS performed in patients at early stages of the disease. Preliminary DPIV measurements show that the pulsatile blood flow discharging into the cavity of the aneurysm leads to large spikes of pressure and wall shear stresses near and around its distal end, indicating a possible correlation between the regions of high wall shear stresses and the observed location of the growth of the aneurysm.

  11. Abdominal aortic feminism.

    PubMed

    Mortimer, Alice Emily

    2014-01-01

    A 79-year-old woman presented to a private medical practice 2 years previously for an elective ultrasound screening scan. This imaging provided the evidence for a diagnosis of an abdominal aortic aneurysm (AAA) to be made. Despite having a number of recognised risk factors for an AAA, her general practitioner at the time did not follow the guidance set out by the private medical professional, that is, to refer the patient to a vascular specialist to be entered into a surveillance programme and surgically evaluated. The patient became symptomatic with her AAA, was admitted to hospital and found to have a tender, symptomatic, 6 cm leaking AAA. She consented for an emergency open AAA repair within a few hours of being admitted to hospital, despite the 50% perioperative mortality risk. The patient spent 4 days in intensive care where she recovered well. She was discharged after a 12 day hospital stay but unfortunately passed away shortly after her discharge from a previously undiagnosed gastric cancer. PMID:25398912

  12. Estimation of prenatal aorta intima-media thickness in ultrasound examination

    NASA Astrophysics Data System (ADS)

    Veronese, Elisa; Poletti, Enea; Cosmi, Erich; Grisan, Enrico

    2012-03-01

    Prenatal events such as intrauterine growth restriction have been shown to be associated with an increased thickness of abdominal aorta in the fetus. Therefore the measurement of abdominal aortic intima-media thickness (aIMT) has been recently considered a sensitive marker of artherosclerosis risk. To date measure of aortic diameter and of aIMT has been performed manually on US fetal images, thus being susceptible to intra- and inter- operator variability. This work introduces an automatic algorithm that identifies abdominal aorta and estimates its diameter and aIMT from videos recorded during routine third trimester ultrasonographic fetal biometry. Firstly, in each frame, the algorithm locates and segments the region corresponding to aorta by means of an active contour driven by two different external forces: a static vector field convolution force and a dynamic pressure force. Then, in each frame, the mean diameter of the vessel is computed, to reconstruct the cardiac cycle: in fact, we expect the diameter to have a sinusoidal trend, according to the heart rate. From the obtained sinusoid, we identify the frames corresponding to the end diastole and to the end systole. Finally, in these frames we assess the aIMT. According to its definition, we consider as aIMT the distance between the leading edge of the blood-intima interface, and the leading edge of the media-adventitia interface on the far wall of the vessel. The correlation between end-diastole and end-systole aIMT automatic and manual measures is 0.90 and 0.84 respectively.

  13. Determination of the layer-specific distributed collagen fibre orientations in human thoracic and abdominal aortas and common iliac arteries

    PubMed Central

    Schriefl, Andreas J.; Zeindlinger, Georg; Pierce, David M.; Regitnig, Peter; Holzapfel, Gerhard A.

    2012-01-01

    The established method of polarized microscopy in combination with a universal stage is used to determine the layer-specific distributed collagen fibre orientations in 11 human non-atherosclerotic thoracic and abdominal aortas and common iliac arteries (63 ± 15.3 years, mean ± s.d.). A dispersion model is used to quantify over 37 000 recorded fibre angles from tissue samples. The study resulted in distinct fibre families, fibre directions, dispersion and thickness data for each layer and all vessels investigated. Two fibre families were present for the intima, media and adventitia in the aortas, with often a third and sometimes a fourth family in the intima in the respective axial and circumferential directions. In all aortas, the two families were almost symmetrically arranged with respect to the cylinder axis, closer to the axial direction in the adventitia, closer to the circumferential direction in the media and in between in the intima. The same trend was found for the intima and adventitia of the common iliac arteries; however, there was only one preferred fibre alignment present in the media. In all locations and layers, the observed fibre orientations were always in the tangential plane of the walls, with no radial components and very small dispersion through the wall thickness. A wider range of in-plane fibre orientations was present in the intima than in the media and adventitia. The mean total wall thickness for the aortas and the common iliac artery was 1.39 and 1.05 mm, respectively. For the aortas, a slight thickening of the intima and a thinning of the media in increasingly distal regions were observed. A clear intimal thickening was present distal to the branching of the celiac arteries. All data, except for the media of the common iliac arteries, showed two prominent collagen fibre families for all layers so that two-fibre family models seem most appropriate. PMID:22171063

  14. Incentive spirometry after abdominal surgery.

    PubMed

    Davis, Suja P

    Patients face various possible complications after abdominal surgery. This article examines best practice in guiding and teaching them how to use an incentive spirometer to facilitate recovery and prevent respiratory complications. PMID:22866486

  15. Understanding the pathogenesis of abdominal aortic aneurysms

    PubMed Central

    Kuivaniemi, Helena; Ryer, Evan J.; Elmore, James R.; Tromp, Gerard

    2016-01-01

    Summary An aortic aneurysm is a dilatation in which the aortic diameter is ≥ 3.0 cm. If left untreated, the aortic wall continues to weaken and becomes unable to withstand the forces of the luminal blood pressure resulting in progressive dilatation and rupture, a catastrophic event associated with a mortality of 50 – 80%. Smoking and positive family history are important risk factors for the development of abdominal aortic aneurysms (AAA). Several genetic risk factors have also been identified. On the histological level, visible hallmarks of AAA pathogenesis include inflammation, smooth muscle cell apoptosis, extracellular matrix degradation, and oxidative stress. We expect that large genetic, genomic, epigenetic, proteomic and metabolomic studies will be undertaken by international consortia to identify additional risk factors and biomarkers, and to enhance our understanding of the pathobiology of AAA. Collaboration between different research groups will be important in overcoming the challenges to develop pharmacological treatments for AAA. PMID:26308600

  16. Extra-abdominal periosteal desmoid tumor of the third toe.

    PubMed

    Saleem, Omar; Sayres, Stephanie; O'Malley, Martin

    2013-09-01

    Extra-abdominal periosteal desmoid tumors are uncommon nonmetastatic tumors of the extremities with a propensity for local recurrence. Lesions in the distal extremities are rare; a majority of extra-abdominal lesions occur in more proximal portions of the upper and lower extremities. This article reports a patient with an extra-abdominal periosteal desmoid tumor in the toe. A 37-year-old woman had a mass in her left third distal phalanx that was originally noted 3 years prior to presenting to the authors' institution. She reported the mass expanded during pregnancy. The toe was red and elongated and had expanded to approximately the same size as her great toe. The plantar aspect of the toe was thick and callused, and the toenail was slightly elevated. Marginal excision with retention of the nail was performed without complication. The mass was determined to be an extra-abdominal periosteal desmoid tumor and was successfully removed without recurrence. To date, the patient remains asymptomatic, with no pain and complete sensation in her third toe. Although extra-abdominal periosteal desmoid tumors have been identified in the extremities, to the authors' knowledge none have been reported as far distal as the toe. Identifying this lesion in the distal extremity will allow a hasty diagnosis and treatment in future cases of similar presentation. Knowledge of the existence of this type of tumor in the distal extremity may also assist in narrowing differential diagnoses. PMID:24025015

  17. Microwave background distortions from domain walls

    NASA Technical Reports Server (NTRS)

    Goetz, Guenter; Noetzold, Dirk

    1990-01-01

    Domain walls arising in a cosmic phase transition after decoupling were recently proposed as seeds for the formation of large scale structure. The distortion induced in the microwave background radiation is calculated in dependence of the wall thickness, surface density, scalar field potential, cosmic redshift and the velocity of the wall. It was found that the maximal redshift distortion for both spherical and planar walls is of the order pi G sigma H(sup -1)(sub 0), where sigma is the surface energy density and H(sup -1)(sub 0) the Hubble parameter. It was also found that, for a wall thickness smaller than the horizon, walls can be treated as infinitely thin, i.e., the redshift distortion is independent of the wall thickness and the specific form of the scalar potential. For planar walls moving with a Lorentz-factor gamma the redshift distortion is enhanced by gamma cubed.

  18. Abdominal pain and faeculent vomiting in a 64-year-old woman.

    PubMed

    Winters, Leigha; Krell, Robert W; Machado-Aranda, David

    2016-01-01

    A 64-year-old woman with a previous right colectomy presented with severe epigastric abdominal pain and nausea of several weeks' duration, which then escalated to projectile faeculent emesis. During her clinical course, she remained afebrile with normal vital signs. Physical examination revealed abdominal distension, moderate tenderness in the bilateral upper quadrants and provoked voluntary abdominal wall guarding. Haematology and laboratory chemistries were only notable for a mild (14.6 K/μL) leucocytosis. Acute abdominal plain radiological series revealed dilated small bowel loops and possible pneumoperitoneum. Abdominal CT demonstrated a mechanical small bowel obstruction and no extraluminal air. An exploratory laparotomy was performed, revealing an obstructing enterolith related to actively inflamed jejunal diverticulitis (complicated JD). This case report aims to describe the non-specific presentation of a poorly understood disease entity that presents a diagnostic and therapeutic challenge for the medical community. PMID:26729826

  19. Significance of bacterial flora in abdominal irradiation-induced inhibition of lung metastases

    SciTech Connect

    Matsumoto, T.; Ando, K.; Koike, S.

    1988-06-01

    We have previously reported that abdominal irradiation prior to i.v. injection of syngeneic tumor cells reduced metastases in lung. Our report described an investigation of the significance of intestinal organisms in the radiation effect. We found that eliminating intestinal organisms with antibiotics totally abolished the radiation effect. Monoassociation of germ-free mice revealed that the radiation effect was observable only for Enterobacter cloacae, never for Streptococcus faecium, Bifidobacterium adlesentis, or Escherichia coli. After abdominal irradiation of regular mice, E. cloacae multiplied in cecal contents, adhered to mucous membranes, invaded the cecal wall, and translocated to mesenteric lymph nodes. Intravenous administration of E. cloacae in place of abdominal irradiation inhibited metastases. E. cloacae-monoassociated mice developed fewer metastases than germ-free mice, and the reduction was further enhanced by abdominal irradiation. We concluded that abdominal irradiation caused the invasion of E. cloacae from the mucous membrane of the intestine and inhibited formation of lung metastases.

  20. Abdominal emergencies in the geriatric patient

    PubMed Central

    2014-01-01

    Abdominal pain is one of the most frequent reasons that elderly people visit the emergency department (ED). In this article, we review the deadliest causes of abdominal pain in this population, including mesenteric ischemia, abdominal aortic aneurysm, and appendicitis and potentially lethal non-abdominal causes. We also highlight the pitfalls in diagnosing, or rather misdiagnosing, these clinical entities. PMID:25635203