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Sample records for abdominal wall thickness

  1. 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

  2. Lateral Abdominal Wall Reconstruction

    PubMed Central

    Baumann, Donald P.; Butler, Charles E.

    2012-01-01

    Lateral abdominal wall (LAW) defects can manifest as a flank hernias, myofascial laxity/bulges, or full-thickness defects. These defects are quite different from those in the anterior abdominal wall defects and the complexity and limited surgical options make repairing the LAW a challenge for the reconstructive surgeon. LAW reconstruction requires an understanding of the anatomy, physiologic forces, and the impact of deinnervation injury to design and perform successful reconstructions of hernia, bulge, and full-thickness defects. Reconstructive strategies must be tailored to address the inguinal ligament, retroperitoneum, chest wall, and diaphragm. Operative technique must focus on stabilization of the LAW to nonyielding points of fixation at the anatomic borders of the LAW far beyond the musculofascial borders of the defect itself. Thus, hernias, bulges, and full-thickness defects are approached in a similar fashion. Mesh reinforcement is uniformly required in lateral abdominal wall reconstruction. Inlay mesh placement with overlying myofascial coverage is preferred as a first-line option as is the case in anterior abdominal wall reconstruction. However, interposition bridging repairs are often performed as the surrounding myofascial tissue precludes a dual layered closure. The decision to place bioprosthetic or prosthetic mesh depends on surgeon preference, patient comorbidities, and clinical factors of the repair. Regardless of mesh type, the overlying soft tissue must provide stable cutaneous coverage and obliteration of dead space. In cases where the fasciocutaneous flaps surrounding the defect are inadequate for closure, regional pedicled flaps or free flaps are recruited to achieve stable soft tissue coverage. PMID:23372458

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

    PubMed Central

    Kok, Amy Siu Yan

    2016-01-01

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

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

    PubMed

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

    2014-05-01

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

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

    PubMed

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

    2014-05-01

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

  6. Congenital lateral abdominal wall hernia.

    PubMed

    Montes-Tapia, Fernando; Cura-Esquivel, Idalia; Gutiérrez, Susana; Rodríguez-Balderrama, Isaías; de la O-Cavazos, Manuel

    2016-08-01

    Congenital abdominal wall defects that are located outside of the anterior wall are extremely rare and difficult to classify because there are no well accepted guidelines. There are two regions outside of the anterior wall: the flank or lateral wall; and the lumbar region. We report the case of a patient with an oval 3 cm-diameter hernia defect located above the anterior axillary line, which affects all layers of the muscular wall. An anorectal malformation consisting of a recto-vestibular fistula was also identified, and chest X-ray showed dextrocardia. The suggested treatment is repair of the defect before 1 year of age. Given that the anomalies described may accompany lateral abdominal wall hernia, it is important to diagnose and treat the associated defects.

  7. Mechanical strength vs. degradation of a biologically-derived surgical mesh over time in a rodent full thickness abdominal wall defect.

    PubMed

    Costa, A; Naranjo, J D; Turner, N J; Swinehart, I T; Kolich, B D; Shaffiey, S A; Londono, R; Keane, T J; Reing, J E; Johnson, S A; Badylak, S F

    2016-11-01

    The use of synthetic surgical mesh materials has been shown to decrease the incidence of hernia recurrence, but can be associated with undesirable effects such as infection, chronic discomfort, and adhesion to viscera. Surgical meshes composed of extracellular matrix (i.e., biologically-derived mesh) are an alternative to synthetic meshes and can reduce some of these undesirable effects but are less frequently used due to greater cost and perceived inadequate strength as the mesh material degrades and is replaced by host tissue. The present study assessed the temporal association between mechanical properties and degradation of biologic mesh composed of urinary bladder matrix (UBM) in a rodent model of full thickness abdominal wall defect. Mesh degradation was evaluated for non-chemically crosslinked scaffolds with the use of (14)C-radiolabeled UBM. UBM biologic mesh was 50% degraded by 26 days and was completely degraded by 90 days. The mechanical properties of the UBM biologic mesh showed a rapid initial decrease in strength and modulus that was not proportionately associated with its degradation as measured by (14)C. The loss of strength and modulus was followed by a gradual increase in these values that was associated with the deposition of new, host derived connective tissue. The strength and modulus values were comparable to or greater than those of the native abdominal wall at all time points. PMID:27619242

  8. A New Rat Model for Orthotopic Abdominal Wall Allotransplantation

    PubMed Central

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

    2014-01-01

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

  9. [FUNCTIONAL PLASTIC OF ANTERIOR ABDOMINAL WALL HERNIAS].

    PubMed

    Grubnik, V V; Parfentyeva, N D; Parfentyev, R S

    2015-07-01

    In order to improve the treatment efficacy of postoperative anterior abdominal wall hernias the method of plastic with restoration of anatomical and physiological properties of the muscles of the anterior abdominal wall was used. After the intervention by the improved method, regardless of the location of the hernia defect yielded promising results for the conservation of anterior abdominal wall muscle function in 75% of cases completely restored functional ability of muscles recti abdomini. PMID:26591212

  10. 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 ...

  11. Tube wall thickness measurement apparatus

    DOEpatents

    Lagasse, Paul R.

    1987-01-01

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and circumference by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  12. Tube wall thickness measurement apparatus

    DOEpatents

    Lagasse, P.R.

    1985-06-21

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and radius by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  13. Acellular dermal matrix in abdominal wall reconstruction.

    PubMed

    Silverman, Ronald P

    2011-09-01

    Abdominal wall reconstruction is a complex and challenging surgical undertaking. While permanent prosthetic mesh is considered the gold standard for minimizing hernia recurrence, placement of synthetic mesh is sometimes imprudent due to contamination or risk of infection. Acellular dermal matrices (ADM) offer an exciting biologic alternative. This article provides a historical perspective on the evolution of complex ventral hernia repair leading up to and including the placement of ADM, an explanation of the biology of ADM as it relates to ventral hernia repair, and a description of the current indications, techniques, benefits, and shortcomings of its use in the abdominal wall.

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

    PubMed

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

    1996-12-01

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

  15. Myxoid Liposarcoma in the Abdominal Wall

    PubMed Central

    Fan, Zhe; Tian, Xiao Feng; Tang, Shun Xiong; Zhang, Ying Yi; Pan, Ji Yong; Wang, Shuang

    2014-01-01

    Abstract A liposarcoma is the most common type of soft tissue sarcoma, and most liposarcomas are malignant. The extremities are the most common site for liposarcomas. There are 5 histologic types of liposarcoma, as follows: well differentiated; myxoid; round cell; pleomorphic; and dedifferentiated. Myxoid liposarcomas (MLSs) represent a subgroup of liposarcomas. There has been no report of MLSs in the abdominal wall. We report a rare case of a MLS of a 43-year-old male who presented with tensile force on the abdominal wall. Computed tomography (CT) found a tumor in abdominal wall. There was no other abnormal symptom and the laboratory testing was also unusual. At last, the tumor was successfully excised, which was diagnosed MLSs in pathology. Following standard principles, after complete excision, the patient received radiotherapy. The patient was followed up for 8 month and no disease recurrence was identified. MLSs are rarely seen in the clinic, irrespective of the presenting signs, but also based on histologic features. The aim of this report was to present the differential diagnosis of an abdominal wall mass, and to remind us of MLSs. PMID:25526446

  16. Solitary fibrous tumor of the abdominal wall.

    PubMed

    Migita, Kazuhiro; Watanabe, Akihiko; Nakagawa, Kenji; Ohyama, Takao; Sekigawa, Susumu

    2009-12-01

    Solitary fibrous tumors (SFTs) are uncommon neoplasms of mesenchymal origin that usually arise from the pleura. SFTs of the abdominal wall are extremely rare, and only 12 cases have been reported in the English language literature. This report presents a new case of SFT of the abdominal wall in a 74-year-old female. Positron emission tomography demonstrated the heterogeneous 18F-fluorodeoxyglucose uptake of the tumor (the maximum standardized uptake value was 2.8). Histologically, the mitotic count was 1 to 2/10 high-power fields. The patient is alive without recurrence at 10 months after undergoing a surgical excision. We discuss the clinicopathological features and differential diagnosis and present a review of the pertinent literature.

  17. Mesh Sutured Repairs of Abdominal Wall Defects

    PubMed Central

    Lanier, Steven T.; Jordan, Sumanas W.; Miller, Kyle R.; Ali, Nada A.; Stock, Stuart R.

    2016-01-01

    Background: A new closure technique is introduced, which uses strips of macroporous polypropylene mesh as a suture for closure of abdominal wall defects due to failures of standard sutures and difficulties with planar meshes. Methods: Strips of macroporous polypropylene mesh of 2 cm width were passed through the abdominal wall and tied as simple interrupted sutures. The surgical technique and surgical outcomes are presented. Results: One hundred and seven patients underwent a mesh sutured abdominal wall closure. Seventy-six patients had preoperative hernias, and the mean hernia width by CT scan for those with scans was 9.1 cm. Forty-nine surgical fields were clean-contaminated, contaminated, or dirty. Five patients had infections within the first 30 days. Only one knot was removed as an office procedure. Mean follow-up at 234 days revealed 4 recurrent hernias. Conclusions: Mesh sutured repairs reliably appose tissue under tension using concepts of force distribution and resistance to suture pull-through. The technique reduces the amount of foreign material required in comparison to sheet meshes, and avoids the shortcomings of monofilament sutures. Mesh sutured closures seem to be tolerant of bacterial contamination with low hernia recurrence rates and have replaced our routine use of mesh sheets and bioprosthetic grafts. PMID:27757361

  18. Abdominal wall fat index in neonates: correlation with birth size.

    PubMed

    Alves, J G; Silva, E; Didier, R; Bandeira, M; Bandeira, F

    2010-06-01

    Low birth weight is associated with obesity in later life and a more central fat distribution has a positive correlation with cardiovascular disease. However, the correlation between visceral adiposity in newborns and birth size is unknown. We measured the visceral adiposity in 118 newborns using the abdominal wall fat index (AFI), ratio between the maximum thickness of preperitoneal and the minimum thickness of subcutaneous fat evaluated by ultrasound. There was a weak negative correlation between AFI and birth weight (r = -0.197; P = 0.033) but not with birth length (r = -0.118; P = 0.201), body mass index (r = -0.138; P = 0.176) and abdominal circumference (r = 0.063; P = 0.497). In conclusion, we suggest that AFI is a useful parameter for evaluating the fat distribution in newborns and that visceral adiposity has a weak negative correlation with birth weight.

  19. 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.

  20. Creating universes with thick walls

    NASA Astrophysics Data System (ADS)

    Ulvestad, Andrew; Albrecht, Andreas

    2012-05-01

    We study the dynamics of a spherically symmetric false vacuum bubble embedded in a true vacuum region separated by a “thick wall”, which is generated by a scalar field in a quartic potential. We study the “Farhi-Guth-Guven” (FGG) quantum tunneling process by constructing numerical solutions relevant to this process. The Arnowitt-Deser-Misner mass of the spacetime is calculated, and we show that there is a lower bound that is a significant fraction of the scalar field mass. We argue that the zero mass solutions used to by some to argue against the physicality of the FGG process are artifacts of the thin wall approximation used in earlier work. We argue that the zero mass solutions should not be used to question the viability of the FGG process.

  1. Restoration of abdominal wall integrity as a salvage procedure in difficult recurrent abdominal wall hernias using a method of wide myofascial release.

    PubMed

    Levine, J P; Karp, N S

    2001-03-01

    The management of primary and recurrent giant incisional hernias remains a complex and frustrating challenge even with multiple alloplastic and autogenous closure options. The purpose of this study was to develop a reconstructive technique of restoring abdominal wall integrity to a subcategory of patients, who have failed initial hernia therapy, by performing superior and lateral myofascial release. Over a 1.5-year period, 10 patients with previously unsuccessful treatment of abdominal wall hernias, using either primary repair or placement of synthetic material, were studied. The patients had either recurrence of the hernia or complications such as infections requiring removal of synthetic material. The hernias were not able to be treated with standard primary closure techniques or synthetic material. The average defect size was 19 x 9 cm. Each patient underwent wide lysis of bowel adhesions releasing the posterior abdominal wall fascia to the posterior axillary line, subcutaneous release of the anterior abdominal wall fascia to a similar level, and complete removal of any synthetic material (if present). The abdominal domain was reestablished by releasing the laterally retracted abdominal wall. The amount of available abdominal wall tissue was increased by wide release of the cephalic abdominal wall fascia overlying the costal margin and the external oblique fascia and muscle laterally. If needed, partial thickness of the internal oblique muscle and its anterior fascia were also released laterally to perform a tension-free primary closure of the defect. All repairs were closed with satisfactory functional and aesthetic results. All alloplastic material was removed. Fascial release was limited so as to close only the hernia defect without tension. No significant release of the rectus sheath and muscle was needed. Good, dynamic muscle function was noted postoperatively. All repairs have remained intact, and no further abdominal wall hernias have been noted on follow-up.

  2. Handlebar Hernia: A Rare Type of Abdominal Wall Hernia

    PubMed Central

    Hassan, Khairi A. F.; Elsharawy, Mohamed A.; Moghazy, Khaled; AlQurain, Abdulaziz

    2008-01-01

    Handlebar hernias are abdominal wall hernias resulting from direct trauma to the anterior abdominal wall. They usually result at weak anatomic locations of the abdominal wall. Such traumatic hernias are rare, requiring a high index of suspicion for a clinical diagnosis. We report the case of a handlebar hernia resulting from an injury sustained during a vehicular injury, and discuss the management of such injuries. PMID:19568493

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

    PubMed

    Ernest Ong, C W; Siow, S L

    2016-04-01

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

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

    PubMed Central

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

    2016-01-01

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

  5. Advanced Gastric Cancer Perforation Mimicking Abdominal Wall Abscess

    PubMed Central

    Cho, Jinbeom; Park, Ilyoung; Lee, Dosang; Sung, Kiyoung; Baek, Jongmin

    2015-01-01

    Surgeons occasionally encounter a patient with a gastric cancer invading an adjacent organ, such as the pancreas, liver, or transverse colon. Although there is no established guideline for treatment of invasive gastric cancer, combined resection with radical gastrectomy is conventionally performed for curative purposes. We recently treated a patient with a large gastric cancer invading the abdominal wall, which was initially diagnosed as a simple abdominal wall abscess. Computed tomography showed that an abscess had formed adjacent to the greater curvature of the stomach. During surgery, we made an incision on the abdominal wall to drain the abscess, and performed curative total gastrectomy with partial excision of the involved abdominal wall. The patient received intensive treatment and wound management postoperatively with no surgery-related adverse events. However, the patient could not receive adjuvant chemotherapy and expired on the 82nd postoperative day. PMID:26468420

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

    PubMed

    Vukšić, Tihomir; Rastović, Pejana; Dragišić, Vedran

    2016-01-01

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

  7. 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.

  8. 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.

  9. Desmoid tumor of the abdominal wall: a case report

    PubMed Central

    2011-01-01

    Introduction Desmoid tumors are rare lesions without any metastatic potential but a strong tendency to invade locally and to recur. These tumors are associated with women of fertile age, especially during and after pregnancy. Case presentation The case of a desmoid tumor of the anterior abdominal wall in a 40-year-old Caucasian man with no relevant family history is presented, describing its appearance on computed tomography and ultrasonography. The patient, who presented with a painless mass in the left anterolateral abdomen, had a history of previous urgent abdominal surgery after a shotgun injury two years earlier. Radical resection of the affected abdominal wall musculature was performed, and the defect was reconstructed with polypropylene mesh. Conclusion The diagnosis of desmoid tumor should be strongly considered even in male patients with an abdominal mass and a history of previous abdominal surgery. The goal of its treatment is complete tumor excision and avoidance of the development of complications such as hernia. PMID:21787413

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

    PubMed

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

    2010-03-01

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

  11. 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.

  12. 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.

  13. 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

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

    PubMed Central

    2013-01-01

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

  15. High accuracy wall thickness loss monitoring

    NASA Astrophysics Data System (ADS)

    Gajdacsi, Attila; Cegla, Frederic

    2014-02-01

    Ultrasonic inspection of wall thickness in pipes is a standard technique applied widely in the petrochemical industry. The potential precision of repeat measurements with permanently installed ultrasonic sensors however significantly surpasses that of handheld sensors as uncertainties associated with coupling fluids and positional offsets are eliminated. With permanently installed sensors the precise evaluation of very small wall loss rates becomes feasible in a matter of hours. The improved accuracy and speed of wall loss rate measurements can be used to evaluate and develop more effective mitigation strategies. This paper presents an overview of factors causing variability in the ultrasonic measurements which are then systematically addressed and an experimental setup with the best achievable stability based on these considerations is presented. In the experimental setup galvanic corrosion is used to induce predictable and very small wall thickness loss. Furthermore, it is shown that the experimental measurements can be used to assess the effect of reduced wall loss that is produced by the injection of corrosion inhibitor. The measurements show an estimated standard deviation of about 20nm, which in turn allows us to evaluate the effect and behaviour of corrosion inhibitors within less than an hour.

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

    PubMed Central

    Wang, Frederick; Buonocore, Samuel; Narayan, Deepak

    2011-01-01

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

  17. 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

  18. Abdominal wall closure after a stomal reversal procedure.

    PubMed

    López-Cano, Manuel; Pereira, José Antonio; Villanueva, Borja; Vallribera, Francesc; Espin, Eloy; Armengol Carrasco, Manuel; Arbós Vía, María Antonia; Feliu, Xavier; Morales-Conde, Salvador

    2014-01-01

    The closure of a temporary stoma involves 2 different surgical procedures: the stoma reversal procedure and the abdominal wall reconstruction of the stoma site. The management of the abdominal wall has different areas that should be analyzed such us how to avoid surgical site infection (SSI), the technique to be used in case of a concomitant hernia at the stoma site or to prevent an incisional hernia in the future, how to deal with the incision when the stoma reversal procedure is performed by laparoscopy and how to close the skin at the stoma site. The aim of this paper is to analyze these aspects in relation to abdominal wall reconstruction during a stoma reversal procedure.

  19. 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

  20. 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.

  1. Gas turbine bucket wall thickness control

    SciTech Connect

    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.

  2. Transversus abdominal plane block as a sole anesthetic technique for abdominal wall hematoma drainage.

    PubMed

    Varela, N; Golvano, M; Monedero, P

    2016-10-01

    Transversus abdominal plane (TAP) block is a known and useful technique, widely used for postoperative pain management of abdominal wall incisions. During the past years, and following the expansion of ultrasound guided techniques, its use has even gained more adepts. It is usually used as an adjuvant technique, primarily in order to control postoperative pain and reduce opioids consumption. We report the case of an 82 years old patient admitted for drainage of a postoperative abdominal wall hematoma after correction of a McBurney incisional hernia. The corrective surgery had gone on without incident, under general anesthesia with laryngeal mask. Two weeks later, the patient came back to our emergency department with a clear hematoma of the abdominal wall. Surgery was decided. A sole local anesthetic technique was achieved, using a TAP block. The block was performed under ultrasound guidance, using a subcostal approach. The surgery went on without complications. Therefore, TAP block offers a hemodynamic stability, appropriate intra-operative anesthesia and post-surgical analgesia of the abdominal wall.

  3. [A Case of Abdominal Wall Hernia Rupture during Bevacizumab Treatment].

    PubMed

    Sugimoto, Satoshi; Miyazaki, Yasuaki; Hirose, Sou; Michiura, Toshiya; Fujita, Shigeo; Yamabe, Kazuo; Miyazaki, Satoru; Nagaoka, Makio

    2015-11-01

    A 78 -year-old man with rectal cancer underwent abdominoperineal resection of the rectum. In the postoperative period, the patient experienced wound infection, leading to an abdominal wall hernia. Two years following surgery, a rise in the serum CEA level was seen. A metastatic tumor was detected in the right lung on chest CT. VATS right lung inferior lobe segmental resection was performed. After lobectomy, the serum CEA level continued to increase. Another metastatic tumor was detected in the right lung on chest CT. Chemotherapy with capecitabine, oxaliplatin, and bevacizumab was commenced. The erosive part of the abdominal wall scar hernia extended during the nine weeks of chemotherapy. The chemotherapy was then discontinued. In the follow-up CT scan, a right pleural recurrence, local recurrence in the pelvis, and a liver metastasis were detected. Chemotherapy was re-introduced 3 years after surgery. The erosive part of the abdominal wall hernia again began to spread with chemotherapy recommencement. Four months after restarting chemotherapy, the hernia ruptured, with a loop of the small intestine protruding out of it. The patient covered this with a sheet of vinyl and was taken by the ambulance to our hospital. The erosive part of the abdominal wall hernia had split by 10 cm, and a loop of the small intestine was protruding. As ischemia of the small intestine was not observed, we replaced it into the abdominal cavity, and performed a temporary suture repair of the hernia sac. Following this, bevacizumab was discontinued, and the erosive part reduced. We performed a radical operation for abdominal wall scar hernia repair 11 weeks after the discontinuation of bevacizumab. PMID:26805294

  4. Traumatic abdominal wall hernia with concealed colonic perforation.

    PubMed

    Pathak, D; Mukherjee, R; Das, P; Pathak, D; Gangopadhyay, A; Das, S

    2016-09-01

    Traumatic abdominal wall hernia (TAWH) is a rare clinical entity in terms of aetiology. It occurs following a blunt abdominal injury with energy high enough to cause disruption of the musculoaponeurotic layer but not the elastic skin layer. It is often associated with underlying intra-abdominal injuries, which can be diagnosed either clinically or radiologically. We report a case of TAWH in a young man with associated large bowel transection, which remained undiagnosed in the preoperative period owing to its masked features. He was managed surgically, with no recurrence to date. Considering the high volume of blunt abdominal trauma cases that present to the accident and emergency department, only few cases of TAWH have been reported in the literature. Confusion still exists regarding the timing and mode of management of this condition. PMID:27241601

  5. Can Abdominal Wall Reconstruction Be Safely Performed Without Drains?

    PubMed

    Ramshaw, Bruce; Dean, Jonathan; Forman, Brandie; Heidel, Eric; Gamenthaler, Andrew; Fabian, Michael

    2016-08-01

    The use of closed suction drains in the abdominal wall is a common practice in abdominal wall reconstruction (AWR) operations. Drains can be a conduit for bacteria and can cause pain and discomfort for patients after surgery. A single hernia program has implemented the principles of clinical quality improvement in an attempt to improve outcomes for hernia patients. An attempt at a process improvement was implemented to eliminate the use of drains in AWR by adapting the technique. A total of 102 patients undergoing AWR were included between 8/11 and 9/15 (49 months). Compared with the group before the attempt at eliminating the use of abdominal wall drains (8/11-9/13), the group of patients after the implementation of the attempted process improvement (9/13-9/15) had less wound and pulmonary complications, a shorter hospital stay, less time in the postanesthesia care unit, and less opioid use in the postanesthesia care unit as well as for the entire hospital stay. In this group of AWR patients, an attempt at process improvement that eliminated the use of drains led to improved outcomes. Abdominal wall drains may be able to be safely eliminated with appropriate technique adaptation for AWR. PMID:27657586

  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. 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 <40 Kg/m2, 40-50 Kg/m2, or >50 Kg/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

  8. [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

  9. Asymptomatic abdominal wall endometrioma 15 years after cesarean section.

    PubMed

    Tica, V I; Tomescu, C L; Tomescu, Aneta; Micu, Luminiţa; Zaher, M; Bafani, S; Beghim, M; Serbănescu, L; Tica, Irina

    2006-01-01

    Abdominal wall endometriosis is rare and its diagnosis is difficult. However, the consequences may be serious, like recurrences or even malignant transformation. We report a rarer case of asymptomatic abdominal wall endometrioma, accidentally found during a surgical procedure for a second cesarean section, in a 39-years old patient, without any relevant history of endometriosis. The tumor was subcutaneous, 3/3 cm in size, located in the left angle of the incision from the 15 years previously performed cesarean section and freely mobile in relation with the skin and the fascia. It was excised, with clear margins (to prevent recurrences), during the procedure. The patient was discharged after five days. The postoperative period and the follow-up at one and three months were uneventful. The pathological examination clarified the diagnosis by revealing an endometrioma with decidual reaction. Such a condition may be, therefore, evoked before an abdominal wall tumor, even without specific symptoms, even in a 39-years old woman and longtime after the possible causal surgery. Pathological examination remains the ultimate diagnostic tool. Relevant prophylactic attitude at the end of the cesarean section may be considered.

  10. Wall thickness design and corrosion management

    SciTech Connect

    Gestel, W.M. van; Guijt, J.

    1994-12-31

    In 1995, Norske Shell will install two 36-in. sweet wet gas pipe lines in the Norwegian sector of the North Sea. The lines cross the Norwegian trench with water depths up to 350 meter. For the last 3.5 km. of the route the pipelines will be laid in a tunnel which will be flooded after construction. The two lines will transport largely untreated well fluids from the Troll field to an onshore processing plant at Kollsness, North of Bergen. From there sales gas will be transported to the continent via the Furopipe and Zeepipe systems. Gas contracts covering 30 years have been concluded with gas utilities on the continent. The maximum wall thickness that could be installed was limited by the capabilities of the present generation of lay barges and pipe mill capacities. The over-thickness, i.e. beyond that what is required for pressure containment and external collapse, is available as corrosion allowance. The paper discusses a novel probabilistic approach to define the corrosion control measures. The corrosion control system is based on the injection of glycol for corrosion mitigation and inspection by ultrasonic internal smart pigs, which in combination with identified fall back options, ensure a minimum 50 year service life.

  11. Current options in the management of complex abdominal wall defects.

    PubMed

    Ghazi, Bahair; Deigni, Olivier; Yezhelyev, Maksym; Losken, Albert

    2011-05-01

    The management of complex abdominal wall defects is challenging and often requires an individualized strategy with additional measures to minimize morbidity and recurrence. We retrospectively reviewed all patients who underwent reconstruction of complex abdominal wall defects at Emory Hospital by the senior author over a 7-year period. Abdominal hernia defects were categorized into primary, secondary, and tertiary hernias; infection; composite tumor defects; and dehiscence. Charts were queried for comorbidities, surgical technique, and outcome measures such as complications and recurrence. A total of 165 patients included in the series, with an average age of 52 years, and an average body mass index of 38 kg/m. Mesh was used in 81.8% of cases, 77% of those (mesh) being acellular dermal matrices (ADM). Component separation was performed in 75 patients (45.4%). The overall complication rate was 23.6% (39/165) including infection, delayed healing, skin necrosis, and fistulae, and was higher in patients with 2 or more comorbidities and those who required synthetic mesh reconstruction. The hernia recurrence or bulge was observed in 20.6% (34/165), and 29.4% of these patients required an additional, equally complex procedure. Hernia recurrence was significantly associated with a history of previous recurrent hernia, and hypertension (P < 0.04 and P = 0.001, respectively). Recurrence was higher in patients with 2 or more comorbidities (26% vs. 14%, P = 0.022). The recurrence rate was similar for synthetic and ADM reconstructions; however, the complication rates were higher when synthetic mesh was used. Attention to surgical technique, optimization of comorbidities, and the increased use of biologic meshes will minimize the need for operative intervention of complications following reconstruction of complex abdominal wall defects. Components separation and ADM have been very useful additions to the surgical management in these high-risk patients.

  12. 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.

  13. 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.

  14. Abdominal fat weight and thickness as predictors of total body fat in broilers.

    PubMed

    Sonaiya, E B

    1985-10-01

    In two experiments broilers of both sexes from two strains were reared to 16 weeks of age to determine how total body fat could be estimated and predicted from some carcase traits. In the first experiment, age, carcase weight and abdominal fat thickness were found to be significant factors in the prediction of total body fat weight estimated from abdominal fat weight. In the second experiment abdominal fat weight was the best predictor of total body fat weight, obtained by ether extraction of the minced whole carcase. Inclusion of abdominal fat weight in the prediction equation after carcase weight and abdominal fat thickness significantly improved the regression. If the carcase cannot be weighed and abdominal fat weight is not available, because of the more laborious nature of its determination, then the measurement of abdominal fat thickness can be useful in predicting the total body fat content.

  15. Gallbladder wall thickness: sonographic accuracy and relation to disease.

    PubMed

    Engel, J M; Deitch, E A; Sikkema, W

    1980-05-01

    A prospective study was performed in two parts after sonographic determination of gallbladder wall thickness in 110 consecutive patients. The first part was designed to evaluate accuracy of sonographic measurements in 40 patients on whom intraoperative measurements of wall thickness were obtained. Second, the significance of wall thickness as an indicator of disease was explored by comparing the 40 surgical patients and 44 controls. Sonography was found to be accurate in determining wall thickness to within 1 mm in 93% of patients and 1.5 mm in 100%. Wall thickness greater than 3.5 mm is highly accurate in predicting disease; however, a wall thickness 3 mm or less does not rule out cholecystitis. PMID:6768264

  16. 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.

  17. Congenital Anaplastic Rhabdomyosarcoma Presenting As Abdominal Wall Mass.

    PubMed

    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

  18. 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.

  19. 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.

  20. 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.

  1. [Hematoma of the abdominal wall as differential diagnosis of cystic pelvic tumor].

    PubMed

    Marroquin-Nisch, J; Grüneberger, A; Hewel, T

    1995-02-01

    In a woman patient aged 80 years under anticoagulation with dicumarol (Marcumar), abdominal pain suddenly occurred which was located on the right side as well as signs of acute bleeding. Preoperative sonography and computer scan showed a large, cystic tumour, most likely originating from the right ovary with infiltration of the abdominal wall. Intraoperative diagnosis was a large haematoma of the abdominal wall and the retroperitoneum penetrating into the free abdomen.

  2. 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.

  3. Reconstruction of full thickness chest wall defects.

    PubMed Central

    Morgan, R F; Edgerton, M T; Wanebo, H J; Daniel, T M; Spotnitz, W D; Kron, I L

    1988-01-01

    Over the last 5 years, 14 patients were treated by wide en bloc resection of chest wall tumors with primary reconstruction. There were nine females and five male patients with an age range of 31-77 years. All patients had a skeletal resection of the chest wall. An average of 3.9 ribs were resected in the patients treated. In three patients a partial sternectomy was carried out in conjunction with the rib resections. Chest wall skeletal defects were reconstructed with Prolene mesh, which was placed under tension. Soft tissue reconstruction utilized selected portions of the latissimus dorsi musculocutaneous territory with fasciocutaneous extensions beyond the muscle itself. Primary healing was obtained in all patients and secondary procedures were not required. The average hospitalization was 23 days. All patients survived the resection and reconstruction and were alive 30 days after operation. In selected patients the preservation of a portion of the innervated muscle in situ or the transfer of the muscle with the preservation of its resting length has maintained the majority of the muscle function. Images Fig. 3A. Fig. 3C. Fig. 3D. Fig. 4A. Fig. 4C. Fig. 4D. Fig. 4E. Fig. 5A. Fig. 5B. Fig. 5D. Fig. 6A. Fig. 6C. Fig. 6D. Fig. 6E. Fig. 6F. Fig. 6G. Fig. 6H. PMID:3389939

  4. Postoperative fistula of the abdominal wall after laparascopic cholecystectomy due to lost gallstones.

    PubMed

    Weiler, H; Grandel, A

    2002-06-01

    Abdominal fistula caused by cholesterol gallstones, which remained in the abdominal wall after laparascopic cholecystectomy: a laparascopic cholecystectomy was performed in a 60-years-old man who was diagnosed as acute necrosing cholecystitis due to cholecystolithiasis. After removal of the gallbladder using an Endocath some gallstones remained in the excision channel of the abdominal wall. Therefore, a fistula developed in the excision channel postoperatively. As the wound healing was disturbed an investigation of the abdominal wall was performed by ultrasound. In the former excision channel several small, oval, formations with high echogenicity and faint ultrasound shadows were detected, corresponding to additional gallstones. After excision of granulation tissue and removal of the cholesterol stones, complete healing of the fistula in the abdominal wall was achieved. PMID:12044854

  5. 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.

  6. Evolution of thick domain walls in de Sitter universe

    NASA Astrophysics Data System (ADS)

    Dolgov, A. D.; Godunov, S. I.; Rudenko, A. S.

    2016-10-01

    We consider thick domain walls in a de Sitter universe following paper by Basu and Vilenkin. However, we are interested not only in stationary solutions found therein, but also investigate the general case of domain wall evolution with time. When the wall thickness parameter, δ0, is smaller than H‑1/√2, where H is the Hubble parameter in de Sitter space-time, then the stationary solutions exist, and initial field configurations tend with time to the stationary ones. However, there are no stationary solutions for δ0 >= H‑1/√2. We have calculated numerically the rate of the wall expansion in this case and have found that the width of the wall grows exponentially fast for δ0 gg H‑1. An explanation for the critical value δ0c = H‑1/√2 is also proposed.

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

    PubMed Central

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

    2016-01-01

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

  8. 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.

  9. [Diagnostics and surgical correction of postoperative myofascial defects of lateral abdominal wall and lumbar region].

    PubMed

    Brekhov, E I; Iurasov, A V; Gribunov, Iu P; Repin, I G; Alekseev, A K; Cherniaeva, N A; Zhitnikov, G V

    2009-01-01

    Myofascial defects of lateral abdominal wall and lumbar region occur chiefly after lumbotomy--the most popular access in urosurgery. Meanwhile lumbotomy remains one of the most traumatic accesses through the lateral abdominal wall. Myofascial defects were diagnosed in 48,9% of operated patients with lumbotomy. Of them true postoperative hernias were found in 35,3%; neuropathic hernias - in 13,6%. Since 2002 the originally developed method of lateral abdominal wall reconstruction had been used for the treatment of such patients. The immediate and long-term results (maximal follow-up period 5 years) showed no hernia recurrence or complications in 26 operated patients.

  10. The effect of resistance exercise direction for hip joint stabilization on lateral abdominal muscle thickness

    PubMed Central

    Jung, Ju-Hyeon; Lee, Sang-Yeol

    2016-01-01

    The aim of this study was to determine the effects of resistance direction in hip joint stabilization exercise on change in lateral abdominal muscle thickness in healthy adults. Twenty-six healthy adults were randomly allocated to either a hip stabilization exercise by hip straight resistance group (n=12) or a hip diagonal resistance group (n=14). The outcome measures included contraction thickness ratio in transversus abdominis (TrA), internal oblique (IO) and external oblique, and TrA lateral slide were assessed during the abdominal drawing-in maneuver by b-mode ultrasound. The researcher measured the abdominal muscle thickness of each participant before the therapist began the intervention and at the moment intervention was applied. There was a significant difference in lateral abdominal muscle thickness between the straight resistance exercise of hip joint group and the diagonal resistance exercise of hip joint group. Significant differences were found between the two groups in the percentage of change of muscle thickness of the TrA (P=0.018) and in the thickness ratio of the TrA (P=0.018). Stability exercise accompanied by diagonal resistance on the hip joint that was applied in this study can induce automatic contraction of the IO and TrA, which provides stability to the lumbar spine. PMID:27807520

  11. 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.

  12. Polarizabilities of an Annular Cut in the Thick Wall.

    NASA Astrophysics Data System (ADS)

    Kurennoy, Sergey S.

    1996-05-01

    The electric and magnetic polarizabilities of an aperture are its important characteristics used in the theory of aperture coupling and diffraction of EM waves. The polarizabilities of the aperture having a form of a ring-shaped cut in the plane wall of an arbitrary thickness are calculated by solving corresponding electrostatic or magnetostatic problems using a combination of analytical, variational and numerical methods. The dependences of the polarizabilities on the aperture parameters and on the wall thickness are presented. The results are applied to estimate the beam coupling impedances of button-type beam position monitors.

  13. 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.

  14. Comparison of abdominal muscle thickness according to feedback method used during abdominal hollowing exercise

    PubMed Central

    Lee, Sangyong; Han, Seulki; Lee, Daehee

    2016-01-01

    [Purpose] This study was intended to examine the most effective feedback method for contracting the musculus transversus abdominis muscle by using basic training, a pressure biofeedback unit, and real-time ultrasonographic imaging during abdominal hollowing exercise training. [Subjects and Methods] The subjects in this study were 30 healthy young students in their twenties. Thirty subjects were divided randomly and equally into the basic training, the pressure biofeedback unit, and real-time ultrasonographic imaging groups. All of the subjects received abdominal hollowing exercise training for 15 minutes. The subjects in the pressure biofeedback unit group were trained by using a pressure biofeedback unit. Those in the real-time ultrasonographic imaging group received training with monitoring of possible contraction of their musculus transversus abdominis muscles on ultrasonography. [Results] In all the three groups, the musculus transversus abdominis became significantly thicker, but more significantly in the real-time ultrasonographic imaging group than in the basic training group. [Conclusion] The feedback method using real-time ultrasonographic imaging may be more effective in thickening the musculus transversus abdominis muscle during exercise than the traditional feedback method with manual contact only. However, it is insufficient in terms of overall qualitative improvement of exercise outcome. PMID:27799683

  15. 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.

  16. Combined Visualization of Wall Thickness and Wall Shear Stress for the Evaluation of Aneurysms.

    PubMed

    Glaßer, Sylvia; Lawonn, Kai; Hoffmann, Thomas; Skalej, Martin; Preim, Bernhard

    2014-12-01

    For an individual rupture risk assessment of aneurysms, the aneurysm's wall morphology and hemodynamics provide valuable information. Hemodynamic information is usually extracted via computational fluid dynamic (CFD) simulation on a previously extracted 3D aneurysm surface mesh or directly measured with 4D phase-contrast magnetic resonance imaging. In contrast, a noninvasive imaging technique that depicts the aneurysm wall in vivo is still not available. Our approach comprises an experiment, where intravascular ultrasound (IVUS) is employed to probe a dissected saccular aneurysm phantom, which we modeled from a porcine kidney artery. Then, we extracted a 3D surface mesh to gain the vessel wall thickness and hemodynamic information from a CFD simulation. Building on this, we developed a framework that depicts the inner and outer aneurysm wall with dedicated information about local thickness via distance ribbons. For both walls, a shading is adapted such that the inner wall as well as its distance to the outer wall is always perceivable. The exploration of the wall is further improved by combining it with hemodynamic information from the CFD simulation. Hence, the visual analysis comprises a brushing and linking concept for individual highlighting of pathologic areas. Also, a surface clustering is integrated to provide an automatic division of different aneurysm parts combined with a risk score depending on wall thickness and hemodynamic information. In general, our approach can be employed for vessel visualization purposes where an inner and outer wall has to be adequately represented. PMID:26356964

  17. 49 CFR 178.33-7 - Wall thickness.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Wall thickness. 178.33-7 Section 178.33-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  18. 49 CFR 178.33-7 - Wall thickness.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Wall thickness. 178.33-7 Section 178.33-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  19. 49 CFR 178.33-7 - Wall thickness.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Wall thickness. 178.33-7 Section 178.33-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  20. 49 CFR 178.33a-7 - Wall thickness.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Wall thickness. 178.33a-7 Section 178.33a-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  1. 49 CFR 178.33a-7 - Wall thickness.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Wall thickness. 178.33a-7 Section 178.33a-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  2. 49 CFR 178.33a-7 - Wall thickness.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Wall thickness. 178.33a-7 Section 178.33a-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  3. 49 CFR 178.33-7 - Wall thickness.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Wall thickness. 178.33-7 Section 178.33-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  4. 49 CFR 178.33a-7 - Wall thickness.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Wall thickness. 178.33a-7 Section 178.33a-7 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for...

  5. Significance of preoperative ultrasound measurement of gallbladder wall thickness.

    PubMed

    Majeski, James

    2007-09-01

    Evaluation of patients with signs and symptoms of biliary tract disease usually includes ultrasound assessment of the gallbladder. Does measurement of the thickness of the gallbladder wall yield any significant information to the clinical surgeon? The records of all my patients undergoing cholecystectomy since 1990 were reviewed. The entire series consists of 401 consecutive patients, in whom 388 procedures were completed laparoscopically, with 14 patients requiring conversion to an open cholecystectomy. Each patient's preoperative evaluation included a gallbladder ultrasound, which included measurement of the diameter of the gallbladder wall. The entire series of cholecystectomies was evaluated according to the ultrasound measured diameter of the gallbladder wall. A thin gallbladder wall was less than 3 mm in diameter. A thick gallbladder wall was 3 mm or greater in diameter. Of the 401 consecutive patients who underwent cholecystectomy for symptomatic gallbladder disease, 86 (21.5%) were removed laparoscopically for acalculous disease. Eleven per cent of patients with acalculous cholecystitis had acute cholecystitis and 89 per cent had chronic cholecystitis. Every patient with either a thin or thick gallbladder wall with acalculous cholecystitis had a successful laparoscopic cholecystectomy. Three-hundred fifteen patients had a laparoscopic cholecystectomy for calculous cholecystitis. In patients with calculous cholecystitis, 28.3 per cent had acute cholecystitis and 71.7 per cent had chronic cholecystitis. The gallbladder wall was found to be greater than 3 mm in 38 per cent of patients with acute calculous cholecystitis and greater than 3 mm in 41 per cent of patients with chronic calculous cholecystitis. One-hundred, forty-two patients, out of a series total of 401, had a gallbladder wall thickness greater than 3 mm by preoperative sonography and 14 of these patients (10%) required conversion to an open cholecystectomy. A preoperative gallbladder ultrasound

  6. 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

  7. Reliability of ultrasound thickness measurement of the abdominal muscles during clinical isometric endurance tests.

    PubMed

    ShahAli, Shabnam; Arab, Amir Massoud; Talebian, Saeed; Ebrahimi, Esmaeil; Bahmani, Andia; Karimi, Noureddin; Nabavi, Hoda

    2015-07-01

    The study was designed to evaluate the intra-examiner reliability of ultrasound (US) thickness measurement of abdominal muscles activity when supine lying and during two isometric endurance tests in subjects with and without Low back pain (LBP). A total of 19 women (9 with LBP, 10 without LBP) participated in the study. Within-day reliability of the US thickness measurements at supine lying and the two isometric endurance tests were assessed in all subjects. The intra-class correlation coefficient (ICC) was used to assess the relative reliability of thickness measurement. The standard error of measurement (SEM), minimal detectable change (MDC) and the coefficient of variation (CV) were used to evaluate the absolute reliability. Results indicated high ICC scores (0.73-0.99) and also small SEM and MDC scores for within-day reliability assessment. The Bland-Altman plots of agreement in US measurement of the abdominal muscles during the two isometric endurance tests demonstrated that 95% of the observations fall between the limits of agreement for test and retest measurements. Together the results indicate high intra-tester reliability for the US measurement of the thickness of abdominal muscles in all the positions tested. According to the study's findings, US imaging can be used as a reliable method for assessment of abdominal muscles activity in supine lying and the two isometric endurance tests employed, in participants with and without LBP.

  8. 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

  9. [Approaches to the abdominal cavity and closure of the abdominal wall].

    PubMed

    Dittmar, Y; Rauchfuss, F; Ardelt, M; Settmacher, U

    2011-12-01

    Although minimally invasive approaches to the abdominal cavity are becoming increasingly more important, open surgical techniques are still of essential interest and must be mastered by general and visceral surgeons. The choice of the particular approach depends on the specificity and location of the scheduled procedure. The following article is intended to give an overview on the current literature as well as experiences in the field of open surgical approaches to the abdominal cavity.

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

    PubMed

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

    2002-02-01

    During laparoscopic cholecystectomy, perforation of the gallbladder can occurs in < or = 20% of cases, while gallstone spillage occurs in < or = 6% of cases. In most cases, there are no consequences. Gallstones can be lost in the abdominal wall as well as the abdomen during extraction of the gallbladder. The fate of such lost gallstones, which can lead to the formation of an abscess, an abdominal wall mass, or a persistent sinus, has not been studied adequately. Herein we report the case of a persistent sinus of the abdominal wall after an emergent laparoscopic cholecystectomy in an 82-year-old woman with gangrenous cholecystitis and perforation of the friable wall in association with an empyema of the gallbladder. The culture of the obtained pus was positive for Escherichia coli. After a small leak of dirty fluid from the wound of the epigastric port site of 4 months' duration, surgical exploration under local anesthesia revealed that the sinus was caused by spilled gallstones impacting into the abdominal wall between the posterior sheath and left rectus abdominalis muscle. The removal of the stones resulted in complete healing. Long-term complications after laparoscopic cholecystectomy involving the abdominal wall are rare but important possible consequences that could be avoided. PMID:11967704

  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. [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.

  13. Primary closure of the abdominal wall after "open abdomen" situation.

    PubMed

    Kääriäinen, M; Kuokkanen, H

    2013-01-01

    "Open abdomen" is a strategy used to avoid or treat abdominal compartment syndrome. It has reduced mortality both in trauma and non-trauma abdominal catastrophes but also has created a challenging clinical problem. Traditionally, open abdomen is closed in two phases; primarily with a free skin graft and later with a flap reconstruction. A modern trend is to close the abdomen within the initial hospitalization. This requires multi-professional co-operation. Temporary abdominal closure methods, e.g. negative pressure wound therapy alone or combined with mesh-mediated traction, have been developed to facilitate direct fascial closure. Components separation technique, mesh reinforcement or bridging of the fascial defect with mesh and perforator saving skin undermining can be utilized in the final closure if needed. These techniques can be combined. Choice of the treatment depends on the condition of the patient and size of the fascia and skin defect, and the state of the abdominal contents. In this paper we review the literature on the closure of an open abdomen and present the policy used in our institution in the open abdomen situations.

  14. 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.

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

    PubMed Central

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

    2016-01-01

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

  16. Early changes in wall motion and wall thickness during percutaneous transluminal coronary angioplasty in man.

    PubMed

    Serruys, P W; Jaski, B; Wijns, W; Piscione, F; ten Kate, F; de Feyter, P; van den Brand, M; Hugenholtz, P G

    1986-07-01

    Epicardial wall motion, myocardial wall thickness and segmental wall motion during percutaneous transluminal coronary angioplasty, a situation which resembles the experimental abrupt occlusion of a major coronary artery in the animal laboratory, have been studied in patients undergoing the procedure. Epicardial wall motion was analyzed using biplane cineradiography with frame to frame measurements of distances between pairs of radiopaque epicardial markers, placed at the time of previous cardiac surgery in a patient with a stenosis of a coronary artery bypass graft. Bypass graft occlusion led to early onset of biphasic epicardial late systolic lengthening and early diastolic shortening similar to the regional wall motion abnormality preceding the procedure. Continuous M-mode echocardiogram throughout coronary luminal occlusion, showed a decreased systolic thickening in the septum with a concomitant, prominent notch in early diastole occurring after the seventh beat following occlusion. At the 28th beat, septal systolic motion was absent while only an early diastolic septal motion was observed. Contemporaneously the end-diastolic septal thickness results decreased. Segmental wall motion analysis during ischemia was carried out performing a left ventricular angiogram before, 20 and 50 seconds after the onset of balloon inflation, 5 minutes after completion of the procedure. During the early phase of ischemia, in the ischemic segments, a late systolic lengthening with an early diastolic shortening was observed. We refer to this biphasic motion as the "W" phenomenon which appears to be the early and characteristic change in wall motion and thickness during coronary angioplasty in man.

  17. Thick-wall effects in the theory of resistive wall modes

    SciTech Connect

    Pustovitov, V. D.

    2012-06-15

    Magnetic interaction of the plasma perturbations with the nearby resistive wall is considered as a resistive wall mode (RWM) problem, but with two essential differences from the traditional thin-wall approach. First, the wall is treated as magnetically thick, which means that the skin depth is not assumed larger than the wall thickness. Second, the plasma is allowed to enter the region where the RWM must be deeply unstable without rotation. The latter corresponds to the plasma operation above the no-wall stability limit demonstrated in the DIII-D tokamak [E. J. Strait et al., Phys. Plasmas 11, 2505 (2004)]. It is shown that the rotational stabilization observed in these experiments can be reproduced in this model if the mode is forced to rotate with a frequency above a critical level. The analytical estimates show that this effect (absent in the model based on the thin-wall approximation) is strong at realistic parameters. The model also predicts that the locking of the rotationally stabilized mode gives rise to instability with a growth rate much larger than its thin-wall estimate.

  18. 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

  19. 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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  2. Polymicrobial abdominal wall necrotizing fasciitis after cesarean section.

    PubMed

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

    2012-09-01

    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.

  3. 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.

  4. 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.

  5. Comparison of Abdominal Muscle Thickness with Vaginal Pressure Changes in Healthy Women

    PubMed Central

    Kim, Bo-In; Hwang-Bo, Gak; Kim, Ha-Roo

    2014-01-01

    [Purpose] The purpose of this study was to verify the efficacy of a pelvic floor muscle exercise program by comparing subjects’ muscle thickness with changes in vaginal pressure. [Subjects] Two groups of female participants without a medical history of pelvic floor muscle dysfunction were evaluated. The mean age of Group I was 33.5 years and that of Group II was 49.69 years. [Methods] The participants were instructed to perform a pelvic floor muscle contraction. While measuring the vaginal pressure of the pelvic floor muscle, biofeedback was given on five levels, and the thicknesses of the transversus abdominis, external oblique, and internal oblique muscles were measured with ultrasound. [Results] The thickness of the transversus abdominis muscle was significantly increased at 30 cmH2O in Group I, and at 20 cmH2O in Group II. The thickness of the internal oblique abdominal muscle significantly increased at maximum contraction in Group II. [Conclusion] Different abdominal muscles contracted depending on vaginal pressure. The result may be used to create and implement an exercise program that effectively strengthens the pelvic floor muscles. PMID:24707099

  6. 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...

  7. 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 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...

  8. 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...

  9. 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 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...

  10. 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...

  11. Abdominal wall injuries: rectus abdominis strains, oblique strains, rectus sheath hematoma.

    PubMed

    Johnson, Rob

    2006-04-01

    Abdominal wall injuries are reported to be less common than actually perceived by sports medicine practitioners. National Collegiate Athletic Association injury statistics for 2004-2005 cite a high of 0.71 abdominal muscle injuries per 1000 player-hours in wrestling competition to a low of 0.01 injuries per 1000 player-hours in autumn football practices. British professional soccer clubs reported an incidence of "torso" injuries of up to 7% of all injuries over the course of several seasons. Injury definition is most likely the explanation for this discrepancy. The abdominal wall muscles (rectus abdominis, external and internal obliques, and transverse abdominis) are injured by direct blows to the abdomen or by sudden or repetitive trunk movement, either rotation or flexion/extension. With the exception of the rare rectus sheath hematoma that does not self-tamponade, the treatment for these problems is nonoperative with symptoms guiding rehabilitation and return to play decisions.

  12. QUALITY OF LIFE OF IN PATIENTS SUBMITTED TO ANTERIOR ABDOMINAL WALL LAPAROSCOPIC HERNIOPLASTY

    PubMed Central

    ABDALLA, Ricardo Zugaib; GARCIA, Rodrigo Biscuola; SAID, Danniel Frade; ABDALLA, Beatrice Martinez Zugaib

    2014-01-01

    Background The laparoscopic ventral hernia repair technique made possible surgeries with smaller skin incisions and smaller dissection of the soft tissue around the hernia, therefore with a better wound, a quicker postoperative recovery and a lower complication rate. Aim To evaluate the applicability of a quality of life survey based on the molds of the American Hernia Society, European Hernia Society and Carolinas Equation for Quality of Life, through telephone in patients submitted to laparoscopic hernioplasty by IPOM technique. Methods A retrospective cohort study was made to evaluate the quality of life of 21 patients that underwent anterior abdominal wall laparoscopic hernioplasty by intraperitoneal onlay mesh technique. Questionnaire was applied through telephone. Results Of the 21 patients, 19% felt that the hernia recurred. Also 19% passed through another abdominal wall surgery, and among these, 75% was related to the previously hernia correction. Finally, 81% of patients did not undergo any other abdominal wall surgery. Conclusion It was possible to apply the quality of life questionnary by telephone on patients who underwent an anterior abdominal wall. The results, in its turn, were satisfactory and showed that patients, in general, were satisfied with the surgical procedure. PMID:24676295

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

    PubMed Central

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

    2012-01-01

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

  14. Management of complex abdominal wall defects using acellular porcine dermal collagen.

    PubMed

    Chavarriaga, Luis Felipe; Lin, Edward; Losken, Albert; Cook, Michael W; Jeansonne, Louis O; White, Brent C; Sweeney, John F; Galloway, John R; Davis, S Scott

    2010-01-01

    Multiple techniques have been used for the repair of complex abdominal wall defects after recurrent incisional hernias with varying rates of success. Primary repair has been associated with high recurrence rates, and prosthetic mesh placement is contraindicated in contaminated surgical fields. The development of biologic prostheses has changed the approach to these difficult problems. This study evaluates the management of complex abdominal wall defects using acellular porcine dermal collagen. Between August 2006 and May 2007, 18 patients underwent abdominal wall reconstruction for complex defects with acellular porcine dermal collagen (CollaMend; Bard Inc., Warwick, RI). Patient demographics, preoperative risk factors, previous herniorrhaphy attempts, postoperative complications, recurrences, and long-term results were retrospectively reviewed. Records were reviewed at a mean follow up of 7.3 months; the recurrence rate was 44.4 per cent. A total of 38.9 per cent (seven of 18) developed a postoperative wound complications, including infection in 22.2 per cent (four of 18). All of the patients with infection required prosthesis removal as a result of encapsulation rather than incorporation of the biologic prosthesis. Acellular porcine dermal collagen has the potential for reconstruction of abdominal wall defects with postoperative wound occurrences comparable with other biologic materials. Encapsulation of the material was a major problem in cases with wound infection that required graft removal rather than local wound measures. Hernia recurrence and dehiscence of the graft were problems in noncompromised surgical fields.

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

    PubMed

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

    2011-01-01

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

  16. Strain to failure of pressurized thick wall cylinders

    SciTech Connect

    Priddy, T.G.; Roach, D.P.

    1989-01-01

    The determination of the fully plastic response and pressure limit of a highly pressurized vessel is of considerable importance in design. The plastic-strain response during and following autofrettage operations, in comparison with the limiting strain condition, is of special interest. This paper presents the results of an analysis method for thick wall, high pressure, cylinders where the effective plastic strain distribution through the thickness is the material response variable of primary interest. The limiting value of this effective plastic strain depends on the level of tensile-stress triaxiality which also varies through the thickness. This strain-to-failure criterion is used to predict the complete pressure versus strain response and the maximum pressure for test cylinders. A simple model of effective-stress versus effective plastic strain is employed. This model is quantified by data taken from uniaxial, tension, true-stress-strain curves and from the fracture zone of the tensile specimen. A sample calculation is included and, in a companion paper, a series of burst tubes having properties ranging from brittle to ductile are compared with this analytical method. 21 refs., 5 figs., 2 tabs.

  17. Closure of the abdominal wall with acellular dermal allograft in intestinal transplantation.

    PubMed

    Mangus, R S; Kubal, C A; Tector, A J; Fridell, J A; Klingler, K; Vianna, R M

    2012-12-01

    Loss of abdominal domain is a common problem in intestinal transplantation. Several surgical options are available perioperatively for abdominal wall reconstruction. This study reports the management and complications for intestinal transplant patients with abdominal wall closure either primarily or with foreign material. This single center study reviews the records of intestinal transplant patients between 2004 and 2010. Study outcomes included reoperation for dehiscence, hernia or enterocutaneous fistula. There were 37 of 146 patients (25%) who required implantation of foreign material at transplant. Of these 37, 30 (81%) had implantation of acellular dermal allograft (ADA) and 7 (19%) implantation of another mesh. Perioperative dehiscence was rare with 2/109 (2%) for primary closure, 0/30 (0%) for ADA and 1/7 (14%) for other mesh. There were 12/146 (8%) patients who underwent ventral hernia repair: primary closure 7/109 (6%), ADA 3/30 (10%) and other mesh 2/7 (28%). There were 4/146 (3%) patients who required surgery for enterocutaneous fistulas: 2/109 (2%) primary closure, 1/30 (3%) ADA and 1/7 (14%) synthetic mesh. Abdominal wall reconstruction with ADA biologic mesh provides an expeditious means of performing a tension-free closure of the fascial layer after intestinal transplantation with complications similar to those seen for primary closure.

  18. Use of absorbable mesh as an aid in abdominal wall closure in the emergent setting.

    PubMed

    Buck, J R; Fath, J J; Chung, S K; Sorensen, V J; Horst, H M; Obeid, F N

    1995-08-01

    A surgeon has many options available to aid in the closure of abdominal wall defects in the elective setting. In the emergent setting, active infection or contamination increases the likelihood of infection of permanent prosthetic material and limits the surgical options. In such settings, we have used absorbable mesh (Dexon) as an adjunct to fascial closure until the acute complications resolve. To evaluate the effectiveness of this technique, we reviewed the outcome of such closures in 26 critically ill patients. Between July 1987 and June 1993, 26 patients were identified who had placement of absorbable mesh as part of an emergent laparotomy at a major urban trauma center. Through a retrospective chart review, the incidence of complications and outcome of the closure were tabulated. Seven patients were initially operated on for trauma. Two of the patients had mesh placement at their initial procedure secondary to fascial loss from trauma. The remainder of the patients hd mesh placement during a subsequent laparotomy for complications related to their initial procedure. Indications for these laparotomies included combinations of wound dehiscence, intra-abdominal abscess, anastomotic disruption, and perforation. Mesh placement in patients with intra-abdominal infection created effectively open abdominal wounds that allowed continued abdominal drainage, but required extensive wound care. Despite the absorbable nature of the mesh and often prolonged hospital stay in these ill patients, none of them required reoperation for dehiscence, recurrence of intra-abdominal abscess, or infection of the mesh.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. 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

  20. 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.

  1. 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

  2. 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. PMID:27134381

  3. Effects of bridge exercises with a sling and vibrations on abdominal muscle thickness in healthy adults.

    PubMed

    Gong, Won-tae

    2015-01-01

    In the present study, we aimed to examine the changes in the thickness of the transversus abdominis (TrA) and internal oblique (Io) muscles using ultrasonography in adults who performed bridge exercises with the abdominal drawing-in maneuver and a sling and received micro vibrations. In total, 32 subjects were divided into a therapy (n= 16) and control (n= 16) groups. The therapy group completed nine sets, with four repetitions, of bridge exercises with the sling and received vibrations. The control group completed nine sets, with four repetitions, of bridge exercises with the sling and did not receive vibrations. The thicknesses of the TrA and Io muscles were measured in both groups using ultrasonography before and after therapy. According to the pressure applied to the biofeedback unit, both groups showed significant changes in the thicknesses of the TrA and Io muscles after therapy (P< 0.05). The change in the thickness of the TrA muscle after therapy was significantly different between the 2 groups when the pressures applied at 38, 42, and 46 mmHg (P< 0.05). Moreover, the change in the thickness of the Io muscle did not significantly different between the 2 groups at any of the pressures applied (P> 0.05). These findings indicate that approximately 15 minutes of vibrations during bridge exercises on unstable surfaces with a sling facilitates the activation of the deep trunk muscles and further enhances the activation of the TrA.

  4. 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.

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

    NASA Astrophysics Data System (ADS)

    Moir, R. W.

    1994-04-01

    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 (Li2BeF4), and molten Lil7Pb83 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.

  6. Thick Liquid-Walled, Field-Reversed Configuration

    SciTech Connect

    Moir, R W; Bulmer, R H; Gulec, K; Fogarty, P; Nelson, B; Ohnishi, M; Rensink, M; Rognlien, T D; Santarious, J F; Sze, D K

    2000-09-22

    A thick flowing layer of liquid (e.g., flibe--a molten salt, or Sn{sub 80}Li{sub 20}--a liquid metal) protects the structural walls of the field-reversed configuration (FRC) so that they can last the life of the plant even with intense 14 MeV neutron bombardment from the D-T fusion reaction. The surface temperature of the liquid rises as it passes from the inlet nozzles to the exit or receiver nozzles due to absorption of line and bremsstrahlung radiation, and neutrons. The surface temperature can be reduced by enhancement of convection near the surface to transport hot surface liquid into the cooler interior. This surface temperature must be compatible with a practical heat transport and energy recovery system. The evaporative flux from the wall driven by the surface temperature must also result in an acceptable impurity level in the core plasma. The shielding of the core by the edge plasma is modeled with a 2D transport code for the resulting impurity ions; these ions are either swept out to the distant end tanks, or diffuse to the hot plasma core. An auxiliary plasma between the edge plasma and the liquid wall can further attenuate evaporating flux of atoms and molecules by ionization. The current in this auxiliary plasma might serve as the antenna for the current drive method, which produces a rotating magnetic field. Another method of current drive uses small spheromaks injected along the magnetic fields, which additionally provide fueling along with pellet fueling if necessary.

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

    PubMed Central

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

    2014-01-01

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

  8. The effects of abdominal draw-in maneuver and core exercise on abdominal muscle thickness and Oswestry disability index in subjects with chronic low back pain

    PubMed Central

    Park, Seong-Doo; Yu, Seong-Hun

    2013-01-01

    The purpose of this study was to effects of abdominal draw-in maneuver and core exercise with 4 weeks using the musculoskeletal ultrasonography on muscle thickness and disability in subjects with low back pain. Twenty patients with nonspecific back pain (abdominal draw-in maneuver group: n= 10, core exercise group: n= 10) were recruited in the study. Both group received exercise intervention 3 times a week for 4weeks. The test were based on muscle thickness (transversus abdominis; Tra, internal oblique; IO and external oblique; EO), disability (Oswestry disability index; ODI) measured immediately before and after intervention. The data was measured by SPSS program 12.0 version and analyzed by Paired t-test and Independent t-test. The following results were obtained. The thickness of IO, EO for both group significantly improved except for muscle thickness of Tra. The ODI were significant difference for both groups. As the results of this study, we suggest that it may be effective method to apply to increase for the thickness of Tra, EO using abdominal draw-in maneuver and thickness of IO using core exercise. PMID:24278873

  9. 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

  10. What's new in medical management strategies for raised intra-abdominal pressure: evacuating intra-abdominal contents, improving abdominal wall compliance, pharmacotherapy, and continuous negative extra-abdominal pressure.

    PubMed

    De Keulenaer, Bart; Regli, Adrian; De Laet, Inneke; Roberts, Derek; Malbrain, Manu L N G

    2015-01-01

    In the future, medical management may play an increasingly important role in the prevention and management of intra-abdominal hypertension (IAH). A review of different databases was used (PubMed, MEDLINE and EMBASE) with the search terms 'Intra-abdominal Pressure' (IAP), 'IAH', ' Abdominal Compartment Syndrome' (ACS), 'medical management' and 'non-surgical management'. We also reviewed all papers with the search terms 'IAH', 'IAP' and 'ACS' over the last three years, only extracting those papers which showed a novel approach in the non-surgical management of IAH and ACS.IAH and ACS are associated with increased morbidity and mortality. Non-surgical management is an important treatment option in critically ill patients with raised IAP. There are five medical treatment options to be considered to reduce IAP: 1) improvement of abdominal wall compliance; 2) evacuation of intra-luminal contents; 3) evacuation of abdominal fluid collections; 4) optimisation of fluid administration; and 5) optimisation of systemic and regional perfusion. This paper will review the first three treatment arms of the WSACS algorithm: abdominal wall compliance; evacuation of intra-luminal contents and evacuation of abdominal fluid collections. Emerging medical treatments will be analysed and finally some alternative specific treatments will be assessed. Other treatment options with regard to optimising fluid administration and systemic and regional perfusion will be described elsewhere, and are beyond the scope of this review. Medical management of critically ill patients with raised IAP should be instigated early to prevent further organ dysfunction and to avoid progression to ACS. Many treatment options are available and are often part of routine daily management in the ICU (nasogastric, rectal tube, prokinetics, enema, sedation, body position). Some of the newer treatments are very promising options in specific patient populations with raised IAP. Future studies are warranted to confirm

  11. Use of bovine pericardium graft for abdominal wall reconstruction in contaminated fields

    PubMed Central

    D’Ambra, Luigi; Berti, Stefano; Feleppa, Cosimo; Magistrelli, Prospero; Bonfante, Pierfrancesco; Falco, Emilio

    2012-01-01

    AIM: To employ, in such conditions, a biological graft such as bovine pericardium that offers resistance to infection. METHODS: In our surgical department, from January 2006 to June 2010, 48 patients underwent abdominal wall reconstruction using acellular bovine pericardium; of these 34 patients had a contaminated wound due to diffuse peritonitis (complicated diverticulitis, bowel perforation, intestinal infarction, strangled hernia, etc.) and 14 patients had hernia relapse on infected synthetic mesh. RESULTS: In our series, one patient died of multi-organ failure 3 d after surgery. After placement of the pericardium mesh four cases of hernia relapse occurred. CONCLUSION: Recurrence rate is similar to that of prosthetic mesh repair and the application of acellular bovine pericardium (Tutomesh®, Tutogen Medical Gmbh Germany) is moreover a safe and feasible option that can be employed to manage complicated abdominal wall defects where prosthetic mesh is unsuitable. PMID:22905285

  12. [Laparoscopic treatment of a large trichobezoar in the stomach with gastric perforation and abdominal wall abscess].

    PubMed

    Zaharie, F; Iancu, C; Tanţău, M; Mocan, L; Bartoş, A; Mihăileanu, F; Iancu, D; Tomuş, C; Zaharie, R; Vlad, L

    2010-01-01

    Trichobezoar represents a mass of swallowed hair inside the stomach. Here we report a 17-year-old girl who presented in our department with symptoms of gastric ulcer. Ultrasound examination followed by upper endoscopy revealed a large trichobezoar in the stomach with simultaneous gastric perforation. Laparoscopy also revealed a penetration into the anterior abdominal wall accompanied by abscess at this level. We performed a laparoscopic gastrotomy with trichobezoar extraction and laparoscopic treatment of perforation and abdominal wall abscess. The postoperative evolution was normal and the patient was discharged on the fifth postoperative day. We show that laparoscopic approach may be safely used in the treatment of the large gastric complicated trichobezoar. Several laparoscopic approaches were described for the treatment of tricobezoar and its complications but as far as we know this is the first report of laparoscopic treatment of large tricobezoar and associate gastric perforation.

  13. 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

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

    PubMed Central

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

    2014-01-01

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

  15. 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

  16. 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.

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

    PubMed Central

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

    2016-01-01

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

  18. Value-based Clinical Quality Improvement (CQI) for Patients Undergoing Abdominal Wall Reconstruction.

    PubMed

    Stephan, Bradley; Ramshaw, Bruce; Forman, Brandie

    2015-05-01

    Patients with complex ventral/incisional hernias often undergo an abdominal wall reconstruction (AWR). These operations have a high cost of care and often result in a long hospital stay and high complication rates. Using the principles of clinical quality improvement (CQI), several attempts at process improvement were implemented in one hernia program over a 3-year period. For consecutive cases of patients undergoing abdominal wall reconstruction, process improvement attempts included the use of a long-term resorbable synthetic mesh (TIGR® Resorbable Matrix, Novus Scientific, Uppsala, Sweden) in place of a biologic mesh, the use of the transversus abdominis release approach in place of an open or endoscopic component separation (external oblique release) technique, and the use of a preoperative transversus abdominis plane (TAP) block using a long-acting local anesthetic (Exparel®, Pacira Pharmaceutical, Parsippany, NJ) as a part of perioperative multi-modal pain management and an enhanced recovery program. After over 60 cases, improvement in materials costs and postoperative outcomes were documented. No mesh-related complications occurred and no mesh removal was required. In this real-world, value-based application of CQI, several attempts at process improvement led to decreased costs and improved outcomes for patients who underwent abdominal wall reconstruction for complex ventral/incisional hernias. Value-based CQI could be a tool for improved health care value globally.

  19. 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

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

    PubMed

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

    2013-07-01

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

  1. [Indications and results of preventive endoprosthezing of the abdominal wall during operations on organs of the abdominal cavity and retroperitoneal space].

    PubMed

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

    2011-01-01

    Complex examination and treatment of 120 patients with anatomo-functional insufficiency of the abdominal wall was made after operations on organs of the abdominal cavity and retroperitoneal space. In the 1st group (60 patients) the abdominal wall was sutured by traditional methods. In the 2nd group (60 patients) laparotomy was followed by implantation of polypropylene endoprosthesis by over-aponeurotic method, and suturing of the lateral wall--by sub-aponeurotic method. At the long-term postoperative period the postoperative ventral hernias were formed in 21.6% of patients of the 1st group, in the 2nd group of patients hernias were not detected. Physical component of quality of life of the 2nd group was 1.5 times, and mental component 1.7 times higher than in the 1st group.

  2. Use of computerized tomography of the abdominal wall in the diagnosis of partial post-operative wound dehiscence.

    PubMed Central

    Smith-Behn, J.; Arnold, M.; Might, J.

    1986-01-01

    A patient had occult post-operative partial wound dehiscence which was accurately diagnosed by performing a CT scan of the abdomen. It is suggested that CT scan of the abdominal wall is useful for early diagnosis of occult abdominal wound dehiscence. Images Figure 1 Figure 2 PMID:2946035

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  5. 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.

  6. Three-dimensional collapse and steady flow in thick-walled flexible tubes

    NASA Astrophysics Data System (ADS)

    Marzo, A.; Luo, X. Y.; Bertram, C. D.

    2005-08-01

    Three-dimensional collapse of and steady flow through finite-length elastic tubes are studied numerically. The Navier-Stokes equations coupled with large, nonlinear deformation of the elastic wall are solved by using the finite-element software, FIDAP. Three-dimensional solid elements are used for the elastic wall, allowing us to specify any wall thickness required. Plane-strain results for the cross-sectional shape of thinner-walled tubes are validated by comparison with published numerical data. Three-dimensional results for flow through finite-thickness tubes are in excellent agreement with published numerical results based on thin-shell elements, and are used to show the effects of varying wall thickness. Finally, the computational predictions are compared with experimental pressure area relationships for thick-walled tubes. The simulations confirm a previously neglected experimental finding, that the Young wavespeed can be lower between buckling and osculation for thick tubes than for thinner ones.

  7. Impact of calcifications on patient-specific wall stress analysis of abdominal aortic aneurysms.

    PubMed

    Maier, A; Gee, M W; Reeps, C; Eckstein, H-H; Wall, W A

    2010-10-01

    As a degenerative and inflammatory desease of elderly patients, about 80% of abdominal aortic aneurysms (AAA) show considerable wall calcification. Effect of calcifications on computational wall stress analyses of AAAs has been rarely treated in literature so far. Calcifications are heterogeneously distributed, non-fibrous, stiff plaques which are most commonly found near the luminal surface in between the intima and the media layer of the vessel wall. In this study, we therefore investigate the influence of calcifications as separate AAA constituents on finite element simulation results. Thus, three AAAs are reconstructed with regard to intraluminal thrombus (ILT), calcifications and vessel wall. Each patient-specific AAA is simulated twice, once including all three AAA constituents and once neglecting calcifications as it is still common in literature. Parameters for constitutive modeling of calcifications are thereby taken from experiments performed by the authors, showing that calcifications exhibit an almost linear stress-strain behavior with a Young's modulus E ≥ 40 MPa. Simulation results show that calcifications exhibit significant load-bearing effects and reduce stress in adjacent vessel wall. Average stress within the vessel wall is reduced by 9.7 to 59.2%. For two out of three AAAs, peak wall stress decreases when taking calcifications into consideration (8.9 and 28.9%). For one AAA, simulated peak wall stress increases by 5.5% due to stress peaks near calcification borders. However, such stress singularities due to sudden stiffness jumps are physiologically doubtful. It can further be observed that large calcifications are mostly situated in concavely shaped regions of the AAA wall. We deduce that AAA shape is influenced by existent calcifications, thus crucial errors occur if they are neglected in computational wall stress analyses. A general increase in rupture risk for calcified AAAs is doubted.

  8. Impact of calcifications on patient-specific wall stress analysis of abdominal aortic aneurysms.

    PubMed

    Maier, A; Gee, M W; Reeps, C; Eckstein, H-H; Wall, W A

    2010-10-01

    As a degenerative and inflammatory desease of elderly patients, about 80% of abdominal aortic aneurysms (AAA) show considerable wall calcification. Effect of calcifications on computational wall stress analyses of AAAs has been rarely treated in literature so far. Calcifications are heterogeneously distributed, non-fibrous, stiff plaques which are most commonly found near the luminal surface in between the intima and the media layer of the vessel wall. In this study, we therefore investigate the influence of calcifications as separate AAA constituents on finite element simulation results. Thus, three AAAs are reconstructed with regard to intraluminal thrombus (ILT), calcifications and vessel wall. Each patient-specific AAA is simulated twice, once including all three AAA constituents and once neglecting calcifications as it is still common in literature. Parameters for constitutive modeling of calcifications are thereby taken from experiments performed by the authors, showing that calcifications exhibit an almost linear stress-strain behavior with a Young's modulus E ≥ 40 MPa. Simulation results show that calcifications exhibit significant load-bearing effects and reduce stress in adjacent vessel wall. Average stress within the vessel wall is reduced by 9.7 to 59.2%. For two out of three AAAs, peak wall stress decreases when taking calcifications into consideration (8.9 and 28.9%). For one AAA, simulated peak wall stress increases by 5.5% due to stress peaks near calcification borders. However, such stress singularities due to sudden stiffness jumps are physiologically doubtful. It can further be observed that large calcifications are mostly situated in concavely shaped regions of the AAA wall. We deduce that AAA shape is influenced by existent calcifications, thus crucial errors occur if they are neglected in computational wall stress analyses. A general increase in rupture risk for calcified AAAs is doubted. PMID:20143120

  9. Rejection of Permacol mesh used in abdominal wall repair: a case report.

    PubMed

    Wotton, Franchesca T; Akoh, Jacob A

    2009-09-14

    Permacol mesh has shown promise when used in abdominal wall repair, especially in the presence of a contaminated surgical field. This biomaterial, derived from porcine dermis collagen, has proposed advantages over synthetic materials due to increased biocompatibility and reduced foreign body reaction within human tissues. However, we present a case report describing a patient who displayed rejection to a Permacol mesh when used in the repair of abdominal wound dehiscence following an emergency laparotomy. Review of the English language literature using PubMed and Medline, showed only two previously published cases of explantation of Permacol due to sepsis or wound breakdown. The authors believe this is the first case of severe foreign body reaction leading to rejection of Permacol. Both animal and human studies show conflicting evidence of biocompatibility. There are several reports of successful use of Permacol to repair complex incisional herniae or abdominal walls in the presence of significant contamination. It appears from the literature that Permacol is a promising material, but as we have demonstrated, it has the potential to evoke a foreign body reaction and rejection in certain subjects.

  10. 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.

  11. Assessment of bladder wall thickness in women with overactive bladder

    PubMed Central

    Üçer, Oktay; Gümüş, Bilal; Albaz, Ali Can; Pekindil, Gökhan

    2016-01-01

    Objective To compare bladder wall thickness (BWT) between female patients with overactive bladder (OAB) and aged-matched healthy controls. Material and methods Thirty-six female patients with OAB and 31 healthy women were enrolled in the present prospective observational study. Qmax and Qave were measured by using uroflowmetry in all of the women in the patient and control groups, and also maximum bladder capacity (MBC), post- void residual urine (PVRU), prevoiding and postvoiding BWT were measured by using transabdominal ultrasound. Lower urinary tract symptoms of the participants were assessed by using Overactive Bladder Version-8 (OAB-V8) and International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF). All of the data were statistically compared between the patient and control groups. In the patient group, the relationships between parameters were evaluated correlation analysis. Results The mean age of the patients and controls were similar (respectively, 45.58±12.35 and 44.21±11.60 years (p=0.68). The mean pre- and post-voiding BWT, OAB-V8 and ICIQ-SF scores of the patients were significantly higher than the controls. In the patient group, the moderate positive correlations between BWT with Qmax (p=0.02) and Qave (p=0.02) were found. Conclusion This study showed that the BWTs of the female patients with OAB are higher than those of healthy women. Further studies should investigate the changes in BWT of patients with OAB after treatment of OAB. PMID:27274895

  12. Abdominal obesity is an independent risk factor for increased carotid intima- media thickness in obese children.

    PubMed

    Hacihamdioğlu, Bülent; Okutan, Vedat; Yozgat, Yilmaz; Yildirim, Düzgün; Kocaoğlu, Murat; Lenk, Mustafa Koray; Ozcan, Okan

    2011-01-01

    We aimed in this study to investigate carotid intima-media thickness (IMT) in obese children and evaluate the relationship of IMT to various cardiovascular risk factors. One-hundred four obese children (9.3 +/- 2.5 years) and 30 healthy age-matched control subjects were enrolled in the study. All children were assessed for fasting levels of glucose, insulin, lipid profile, skinfold thickness (SFT), waist circumference (WC), and blood pressure (BP). Insulin resistance was estimated by the homeostasis model assessment (HOMA) index. Carotid IMT measurements and non-alcoholic fatty liver disease (NAFLD) were diagnosed with ultrasonographic findings. IMT was significantly higher in obese children compared to controls (0.49 +/- 0.05 vs. 0.40 +/- 0.02 mm, p < 0.001). Significant positive correlations were found between increased carotid IMT and body fat percentage (BFP), body mass index (BMI), age, height, systolic BP, WC, SFT, triglyceride and insulin levels, and insulin resistance index. In a linear logistic regression analysis, the only parameter affecting the increase in carotid IMT was WC (beta: 0.589, p < 0.001). Furthermore, IMT was increased significantly in obese children with NAFLD when compared to obese children without NAFLD (0.54 +/- 0.04 vs. 0.48 +/- 0.05 mm, p < 0.001). Children with abdominal obesity are at increased risk for atherosclerosis, and WC can be used to determine the atherosclerosis risk in obese children.

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

    PubMed

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

    2011-01-01

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

  14. The influence of intraluminal thrombus on noninvasive abdominal aortic aneurysm wall distensibility measurement.

    PubMed

    Metaxa, Eleni; Kontopodis, Nikolaos; Vavourakis, Vasileios; Tzirakis, Konstantinos; Ioannou, Christos V; Papaharilaou, Yannis

    2015-04-01

    Abdominal aortic aneurysm wall distensibility can be estimated by measuring pulse pressure and the corresponding sac volume change, which can be obtained by measuring wall displacement. This approach, however, may introduce error if the role of thrombus in assisting the wall in bearing the pulse pressure loading is neglected. Our aim was to introduce a methodology for evaluating and potentially correcting this error in estimating distensibility. Electrocardiogram-gated computed tomography images of eleven patients were obtained, and the volume change between diastole and systole was measured. Using finite element procedures, we determined the equivalent pulse pressure loading that should be applied to the wall of a model where thrombus was digitally removed, to yield the same sac volumetric increase caused by applying the luminal pulse pressure to the model with thrombus. The equivalent instead of the measured pulse pressure was used in the distensibility expression. For a relative volumetric thrombus deposition (V ILT) of 50 %, a 62 % distensibility underestimation resulted when thrombus role was neglected. A strong linear correlation was observed between distensibility underestimation and V ILT. To assess the potential value of noninvasive wall distensibility measurement in rupture risk stratification, the role of thrombus on wall loading should be further investigated. PMID:25548097

  15. [Gastrointestinal stromal tumor of the abdominal wall. An unusual localization of a rare tumor].

    PubMed

    Thalheimer, A; Meyer, D; Gattenlöhner, S; Timmermann, W; Thiede, A

    2004-07-01

    Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. We describe here for the first time a patient with a huge GIST of the abdominal wall without any relation to the gastrointestinal tract, omentum, or mesentery. With regard to the size of 24 cm and a low mitotic index, this GIST is considered an intermediate risk for metastasis. Radical surgical resection was performed with negative pathologic resection margins. The classic immunohistochemical phenotype of the tumor described facilitates the differential diagnosis to exclude abdominal desmoid tumor and solitary fibrous tumor (SFT). In the case of metastasis, therapeutic nihilism no longer seems justified with the availability of imatinib, a tyrosine kinase inhibitor, which shows encouraging results in the therapy of metastatic GIST.

  16. 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.

  17. 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

  18. Fluid-Structure Simulations of a Ruptured Intracranial Aneurysm: Constant versus Patient-Specific Wall Thickness

    PubMed Central

    Hoffmann, T.; Beuing, O.; Jachau, K.; Thévenin, D.; Janiga, G.; Berg, P.

    2016-01-01

    Computational Fluid Dynamics is intensively used to deepen the understanding of aneurysm growth and rupture in order to support physicians during therapy planning. However, numerous studies considering only the hemodynamics within the vessel lumen found no satisfactory criteria for rupture risk assessment. To improve available simulation models, the rigid vessel wall assumption has been discarded in this work and patient-specific wall thickness is considered within the simulation. For this purpose, a ruptured intracranial aneurysm was prepared ex vivo, followed by the acquisition of local wall thickness using μCT. The segmented inner and outer vessel surfaces served as solid domain for the fluid-structure interaction (FSI) simulation. To compare wall stress distributions within the aneurysm wall and at the rupture site, FSI computations are repeated in a virtual model using a constant wall thickness approach. Although the wall stresses obtained by the two approaches—when averaged over the complete aneurysm sac—are in very good agreement, strong differences occur in their distribution. Accounting for the real wall thickness distribution, the rupture site exhibits much higher stress values compared to the configuration with constant wall thickness. The study reveals the importance of geometry reconstruction and accurate description of wall thickness in FSI simulations. PMID:27721898

  19. Reducing Effective Liquid Wall Thickness in a HYLIFE-II Fusion Breeder

    NASA Astrophysics Data System (ADS)

    Übeyli, Mustafa

    2004-09-01

    One of the major inertial fusion energy reactor designs is HYLIFE-II which uses protective flowing liquid wall between fusion plasma and solid first wall. The most attractive aspect of this reactor is that protective liquid wall eliminates the frequent replacement of the first wall structure during reactor lifetime. Liquid wall thickness must be at least the thickness required for supplying sufficient tritium for the deuterium-tritium (DT) driver and satisfying radiation damage on the first wall below the limits. Reducing this thickness results less pumping power requirements and cost of electricity. In this study, investigation on potential of utilizing refractory alloys (W-5Re, TZM and Nb-1Zr) as first wall to reduce effective liquid wall thickness in HYLIFE-II reactor using liquid wall of Flibe + 10 mol % UF4 mixture. Neutron transport calculations were carried out with the help of the SCALE4.3 system by solving the Boltzmann transport equation with the XSDRNPM code in 238 neutron groups and a S8-P3 approximation. Numerical results showed that using W-5Re or TZM as first wall was effective in decreasing liquid wall thickness in contrast to Nb-1Zr.

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

    NASA Astrophysics Data System (ADS)

    Glavas, Zoran; Strkalj, Anita; Maldini, Kresimir

    2016-08-01

    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.

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

    PubMed

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

    2007-05-01

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

  2. 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.

  3. [Late metastases of cutaneous malignant melanoma on the abdominal wall to the small and large bowel].

    PubMed

    Füredi, Gábor; Altorjay, Aron; Varga, István; Illés, Iván; Kovács, Csaba; Békefi, Péter; Molnár, Anna

    2005-08-01

    We describe the case of a 56 years old man, who was operated on with abdominal wall skin malignant melanoma 5 years ago. He received postoperative DTIC + Intron A treatment. Five years later he presented with complaints of epigastric pain, melena, hematochezia, anorexia and fatigue. Upper gastrointestinal tract endoscopy showed a tumour mass in the duodeno-jejunal flexure and colonoscopy showed a tumour in the large bowel. Histology verified anaplastic carcinoma. The patient was operated on. We found metastases in the small and the large bowel The patient underwent resection of the jejunum and right hemicolectomy. We describe the different types of metastases of malignant melanomas symptoms, therapies and prognosis.

  4. Heavy Metal Bioaccumulation in an Atypical Primitive Neuroectodermal Tumor of the Abdominal Wall.

    PubMed

    Roncati, Luca; Gatti, Antonietta Morena; Capitani, Federico; Barbolini, Giuseppe; Maiorana, Antonio; Palmieri, Beniamino

    2015-01-01

    Heavy metals are able to interfere with the function of vital cellular components. Besides in trace heavy metals, which are essential at low concentration for humans, there are heavy metals with a well-known toxic and oncogenic potential. In this study, for the first time in literature, we report the unique adulthood case of an atypical primitive neuroectodermal tumor of the abdominal wall, diagnosed by histology and immunohistochemistry, with the molecular hybridization support. The neoplasia occurred in a patient chronically exposed to a transdermal delivery of heavy metal salts (aluminum and bismuth), whose intracellular bioaccumulation has been revealed by elemental microanalysis.

  5. 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

  6. [Assessment of velocity of deformation of abdominal aorta wall with the help of the multivox working station].

    PubMed

    Sandrikov, V A; Fisenko, E P; Gavrilov, A V; Lozhkevich, A A; Platova, E N; Arkhipov, I V

    2013-01-01

    Most frequent cause of abnormalities of elastic properties of walls of abdominal aorta is development of atherosclerosis resulting in replacement of elastin by simpler fibrillar proteins and collagen. This subsequently leads to dilation of the aorta and formation of aneurism. Increase of collagen content in the aortic wall correlates with growth of aneurism dimensions. Main method of treatment of aneurisms is implantation of abdominal aortic prosthesis. Detailed preoperative assessment of functional state of the aortic wall is necessary in preoperative period but none of modern imaging instrumental methods including ultrasound study allows to realize this assessment. In this article we present first experience of assessment of aortic wall deformation velocity analyzing results of ultrasound study with the help of the Multivox working station in 36 patients 16 of whom were operated because of aneurism of abdominal aorta. PMID:24654437

  7. [Reconstruction of an abdominal wall defect with a superior epigastric perforator propeller flap: case report].

    PubMed

    Lepivert, J-C; Alet, J-M; Michot, A; Pélissier, P; Pinsolle, V

    2014-10-01

    Perforators flaps take a special place in reconstructive surgery. These flaps can be dissected and turned as a propeller blade on its pedicule axis. We report the case of a 54-year-old man presenting a recurrence of a dermatofibrosarcoma in the right hypochondrium. Tumor resection caused a large abdominal wall defect taking the anterior aponeurosis of the rectus abdominis. An angioscanner was realized in preoperative to locate the perforators of the deep superior epigastric artery. We realized a propeller flap based on a perforator of the left superior epigastric artery who allowed to cover the wall defect. We set up a patch of Vicryl® to reconstruct the aponeurosis plan at the same operative time. We didn't note any necrosis and complete healing occurred in 2 weeks. The margins were healthy. The cosmetic result and the low morbidity make this flap a good therapeutic option. This flap seems reliable, arteries perforators are constant with good diameter.

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

    PubMed Central

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

    2000-01-01

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

  9. 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.

  10. Impact of exercise training on arterial wall thickness in humans

    PubMed Central

    Thijssen, Dick H. J.; Cable, N. Timothy; Green, Daniel J.

    2011-01-01

    Thickening of the carotid artery wall has been adopted as a surrogate marker of pre-clinical atherosclerosis, which is strongly related to increased cardiovascular risk. The cardioprotective effects of exercise training, including direct effects on vascular function and lumen dimension, have been consistently reported in asymptomatic subjects and those with cardiovascular risk factors and diseases. In the present review, we summarize evidence pertaining to the impact of exercise and physical activity on arterial wall remodelling of the carotid artery and peripheral arteries in the upper and lower limbs. We consider the potential role of exercise intensity, duration and modality in the context of putative mechanisms involved in wall remodelling, including haemodynamic forces. Finally, we discuss the impact of exercise training in terms of primary prevention of wall thickening in healthy subjects and remodelling of arteries in subjects with existing cardiovascular disease and risk factors. PMID:22150253

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  12. 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.

  13. 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

  14. Energy dependent chest wall thickness equations for male lung monitoring with germanium detectors.

    PubMed

    Broggio, D; Lechaftois, X; Abline, O; Fleury, B; Vial, A; Corrèze, P; Franck, D; Merzoug, V

    2014-03-01

    The thickness and fat fraction of the chest wall are important parameters for in vivo lung monitoring. They have been measured from ultrasonic images on 374 male workers of the French nuclear industry using four measurement locations, as dictated by the size and position of the germanium detectors used for monitoring. The plastic muscle equivalent chest wall thickness (PMECWT) and the plastic 50% muscle-50% adipose equivalent chest wall thickness (X5050) have been calculated for each worker at 17, 59.5, and 185.7 keV, respectively. Multi-linear regression models have been tested to predict PMECWT and X5050 as a function of anthropometric measurements. Finally, it was considered whether the average chest wall thickness could be used instead of the material equivalent chest wall thickness. It was found that the mean chest wall thickness was (27 ± 5) mm and the mean fat fraction was (25 ± 8)%. The best and more convenient model for material equivalent chest wall thickness is a linear function of the body mass index. Depending on the energy, the standard errors of estimate for this model range between 3.2-3.4 mm for PMECWT and between 3.2-3.7 mm for X5050. At 59.5 and 185.7 keV, it was determined, to an excellent approximation, that the fat fraction and consideration of an equivalent material are unnecessary, contrary to the case at 17 keV.

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

    PubMed

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

    2014-12-01

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

  16. 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

  17. Pain pressure threshold algometry of the abdominal wall in healthy women

    PubMed Central

    Montenegro, M.L.L.S.; Braz, C.A.; Mateus-Vasconcelos, E.L.; Rosa-e-Silva, J.C.; Candido-dos-Reis, F.J.; Nogueira, A.A.; Poli-Neto, O.B.

    2012-01-01

    The objective of this study was to determine the inter- and intra-examiner reliability of pain pressure threshold algometry at various points of the abdominal wall of healthy women. Twenty-one healthy women in menacme with a mean age of 28 ± 5.4 years (range: 19-39 years) were included. All volunteers had regular menstrual cycles (27-33 days) and were right-handed and, to the best of our knowledge, none were taking medications at the time of testing. Women with a diagnosis of depression, anxiety or other mood disturbances were excluded. Women with previous abdominal surgery, any pain condition or any evidence of inflammation, hypertension, smoking, alcoholism, or inflammatory disease were also excluded. Pain perception thresholds were assessed with a pressure algometer with digital traction and compression and a measuring capacity for 5 kg. All points were localized by palpation and marked with a felt-tipped pen and each individual was evaluated over a period of 2 days in two consecutive sessions, each session consisting of a set of 14 point measurements repeated twice by two examiners in random sequence. There was no statistically significant difference in the mean pain threshold obtained by the two examiners on 2 diferent days (examiner A: P = 1.00; examiner B: P = 0.75; Wilcoxon matched pairs test). There was excellent/good agreement between examiners for all days and all points. Our results have established baseline values to which future researchers will be able to refer. They show that pressure algometry is a reliable measure for pain perception in the abdominal wall of healthy women. PMID:22527127

  18. 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.

  19. 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.

  20. 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.

  1. 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.

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

    DOEpatents

    Burdgick, Steven Sebastian

    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.

  3. 49 CFR 179.500-4 - Thickness of wall.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS... wall of tank multiplied by 3.0 will not exceed the tensile strength of any specimen taken from the tank....0 Where: U = Tensile strength of that specimen which shows the lower tensile strength of the...

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

    PubMed

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

    2009-11-01

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

  5. Clad vent set cup open end (closure weld zone) wall-thickness study

    SciTech Connect

    Ulrich, G.B.; Sherrill, M.W.

    1994-09-01

    The wall thickness at the open end of Clad Vent Set (CVS) cups is a very important parameter for maintaining control of the fueled CVS closure weld process. Ideally, the wall thickness in the closure weld zone should be constant. The DOP-26 iridium alloy is very difficult to machine; therefore, key dimensional features are established during the two-draw warm-forming operation. Unfortunately, anisotropy in the forming blanks produces four ears at the open end of each cup. Formation of these ears produces axial and circumferential variations in wall thickness. The cup certification requirement is that the wall thickness in the closure weld zone, defined as the 2.5-mm band at the open end of a cup, measure from 0.63 to 0.73 mm. The wall thickness certification data for the open end of the CVS cups have been statistically evaluated. These data show that the cups recently produced for the Cassini mission have well-controlled open-end wall thicknesses.

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. Automatic electrical stimulation of abdominal wall muscles increases tidal volume and cough peak flow in tetraplegia.

    PubMed

    Gollee, H; Hunt, K J; Allan, D B; Fraser, M H; McLean, A N

    2008-01-01

    Paralysis of the respiratory muscles in people with tetraplegia affects their ability to breathe and contributes to respiratory complications. Surface functional electrical stimulation (FES) of abdominal wall muscles can be used to increase tidal volume (V_{T}) and improve cough peak flow (CPF) in tetraplegic subjects who are able to breathe spontaneously. This study aims to evaluate the feasibility and effectiveness of a novel abdominal FES system which generates stimulation automatically, synchronised with the subjects' voluntary breathing activity. Four subjects with complete tetraplegia (C4-C6), breathing spontaneously, were recruited. The automatic stimulation system ensured that consistent stimulation was achieved. We compared spirometry during unassisted and FES-assisted quiet breathing and coughing, and measured the effect of stimulation on end-tidal CO_2 (EtCO_2) during quiet breathing. The system dependably recognised spontaneous respiratory effort, stimulating appropriately, and was well tolerated by patients. Significant increases in V_T during quiet breathing (range 0.05-0.23 L) and in CPF (range 0.04-0.49 L/s) were observed. Respiratory rate during quiet breathing decreased in all subjects when stimulated, whereas minute ventilation increased by 1.05-2.07 L/min. The changes in EtCO_2 were inconclusive. The automatic stimulation system augmented spontaneous breathing and coughing in tetraplegic patients and may provide a potential means of respiratory support for tetraplegic patients with reduced respiratory capacity.

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

    PubMed

    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.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2015-01-01

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

  14. 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

  15. Morphological and Mechanical Characteristics of the Reconstructed Rat Abdominal Wall Following use of a Wet Electrospun Biodegradable Polyurethane Elastomer Scaffold

    PubMed Central

    Hashizume, Ryotaro; Fujimoto, Kazuro L.; Hong, Yi; Amoroso, Nicholas J.; Tobita, Kimimasa; Miki, Toshio; Keller, Bradley B.; Sacks, Michael S.; Wagner, William R.

    2011-01-01

    Although a variety of materials are currently used for abdominal wall repair, general complications encountered include herniation, infection, and mechanical mismatch with native tissue. An approach wherein a degradable synthetic material is ultimately replaced by tissue mechanically approximating the native state could obviate these complications. We report here on the generation of biodegradable scaffolds for abdominal wall replacement using a wet electrospinning technique in which fibers of a biodegradable elastomer, poly(ester urethane)urea (PEUU), were concurrently deposited with electrosprayed serum-based culture medium. Wet electrospun PEUU (wet ePEUU) was found to exhibit markedly different mechanical behavior and to possess an altered microstructure relative to dry processed ePEUU. In a rat model for abdominal wall replacement, wet ePEUU scaffolds (1 × 2.5 cm) provided a healing result that developed toward approximating physiologic mechanical behavior at 8 wks. An extensive cellular infiltrate possessing contractile smooth muscle markers was observed together with extensive extracellular matrix (collagens, elastin) elaboration. Control implants of dry ePEUU and expanded polytetrafluoroethylene did not experience substantial cellular infiltration and did not take on the native mechanical anisotropy of the rat abdominal wall. These results illustrate the markedly different in vivo behavior observed with this newly reported wet electrospinning process, offering a potentially useful refinement of an increasingly common biomaterial processing technique. PMID:20138661

  16. Laser Ultrasonic Thickness Measurements of Very Thick Walls at High Temperatures

    SciTech Connect

    Kruger, S. E.; Lord, M.; Monchalin, J.-P.

    2006-03-06

    Laser-ultrasonics presents many advantages compared to conventional ultrasonics, but is, generally, considered as less sensitive. As a consequence, laser-ultrasonics should not be adequate for ultrasonic measurements in coarse microstructure materials or measurements of large thicknesses. However, since the generated waves extend to very low frequencies, measurements in such conditions can be successfully performed if a photorefractive interferometer sensitive also to these low frequencies and properly balanced is used for detection. This is demonstrated by measurements of thicknesses up to 100 mm (4'') for various steel grades and at temperatures up to 1250 deg. C.

  17. 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

  18. [A case of fixing an anastomotic site to the abdominal wall out of the abdominal cavity for a small intestinal perforation during chemotherapy].

    PubMed

    Takahashi, Kazutaka; Harano, Masao; Kato, Takuya; Yoshida, Kazuhiro; Sato, Daisuke; Choda, Yasuhiro; Tokumoto, Noriaki; Kanazawa, Takashi; Matsukawa, Hiroyoshi; Ojima, Yasutomo; Idani, Hitoshi; Shiozaki, Shigehiro; Okajima, Masazumi; Ninomiya, Motoki

    2014-11-01

    A 53-year-old man presented with a continuous high fever and was diagnosed with diffuse large B-cell lymphoma with metastasis to the lung, spleen, and mesenterium. He was treated with cyclophosphamide and prednisolone followed by administration of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) chemotherapy 20 days later. Two days after initiation of CHOP therapy, the patient complained of severe abdominal pain. Perforative peritonitis was diagnosed using abdominal computed tomography. A perforation of the small intestine approximately 160 cm distal to the Treitz ligament was uncovered during emergency laparotomy. The risk of leakage was considered too high for anastomosis of the small intestine to be performed. Further, construction of an intestinal stoma could result in a high-output syndrome that could lead to difficulty in resuming chemotherapy. Based on these considerations, we fixed the anastomotic region to the abdominal wall using a technique similar to construction of an intestinal stoma. Post-operative anastomotic leakage did not occur. Nine days later, a perineal hernia was noted near the anastomotic site and a second operation was performed. The anastomotic site was placed back into the abdominal cavity during this operation. CHOP therapy was resumed 16 days after the first operation.

  19. [Morphology of tissue reactions around implants after combined surgical repair of the abdominal wall].

    PubMed

    Vostrikov, O V; Zotov, V A; Nikitenko, E V

    2004-01-01

    Tissue reactions to titanium-nickelide and polypropylen and caprone implants used in surgical treatment of anterior aldomen wall hernias were studied in experiment. Digital density of leukocytes, fibroblasts, vessels, thickness of the capsule were studied. Pronounced inflammatory reaction was observed on day 3 which attenuated on day 14 in case of titanium nickelide and on day 30-60 in case of polypropylene and caprone. Fibroplastic processes start in the first group after 7 days while in the second group only after 30 days of the experiment. Thickness of the capsule around titanium-nickelide was 2-3 times less than around polypropylene and caprone. Thus, titanium-nickelide material is biologically more inert than caprone and polypropylen which are widely used in surgery of hernias. PMID:15154379

  20. 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.

  1. 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

  2. 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.

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

    PubMed

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

    2016-06-01

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

  4. Dependence of Thermal Conductivity on Thickness in Single-Walled Carbon Nanotube Films.

    PubMed

    Lee, Kyung-Min; Shrestha, Ramesh; Dangol, Ashesh; Chang, Won Seok; Coker, Zachary; Choi, Tae-Youl

    2016-01-01

    Herein, we report experimentally dependence of thermal conductivity on thickness of single walled carbon nanotubes (SWNTs) thin films; the measurements are based on the micropipette thermal sensor technique. Accurate and well resolved measurements of thermal conductivity made by the micropipette sensor showed a correlated behavior of thickness and thermal conductivity of CNT films that thermal conductivity decreased as thickness increased. The thickness dependence is explained by reduction of mean free path (MFP), which is induced by more intertubular junctions in more dense-packed carbon nanotube (CNT) networks; the thicker SWCNT films were revealed to have higher density. PMID:27398564

  5. 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.

  6. 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.

  7. 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.

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

    Hemingway, A; Herrington, L; Blower, A

    2003-01-01

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

  10. [Effect of wall thickness of left ventricle on 201Tl myocardial SPECT images: myocardial phantom study].

    PubMed

    Koto, M; Namura, H; Kawase, O; Yamasaki, K; Kono, M

    1996-07-01

    201Tl myocardial SPECT is known for better sensitivity, specificity, and accuracy than planar images in detecting coronary artery disease and diagnosing myocardial viability. SPECT images are also superior to planar images in diagnostic sensitivity and anatomical orientation. However, as limitation of the spatial resolution of the machine, we often encounter poor SPECT plower image quality in patients with decreased wall thickness. To test the accuracy of SPECT images in patients with marked thinning of the left ventricular wall, as occurs in dilated cardiomyopathy, we performed a experimental study using myocardial phantom with 7 mm wall thickness. Tomographic image of the phantom images were rather heterogeneous, though no artificial defect was located. Dilated cardiomyopathy is thought to be characterized by patchy defects in the left ventricle. Careful attention should be given to elucidating myocardial perfusion in patients with a thin left ventricle wall, as there are technical limitations in addition to clinical features.

  11. [Quality of life after operations in the abdominal and retroperitoneal cavities: the influence of the abdominal wall anatomic-functional insufficiency].

    PubMed

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

    2009-01-01

    120 patients with abdominal wall anatomic-functional insufficiency were examined and treated. All patients were divided in 2 similar groups 60 patients each. Patients of the first group had traditional laparotomy wound closure, whereas patients of the second group overcame polypropylene mesh implantation. 21.6% of patients from the first group revealed postoperative ventral hernias at follow-up, none of the second group faced such a problem. Physical component of the quality of live was 3.2 times, and psychological component - 2,6 times higher in patients of the second group.

  12. Enhancing cell-free layer thickness by bypass channels in a wall.

    PubMed

    Saadatmand, M; Shimogonya, Y; Yamaguchi, T; Ishikawa, T

    2016-07-26

    When blood flows near a wall, red blood cells (RBCs) drift away from the wall and a cell-free layer (CFL) is formed adjacent to the wall. Controlling the CFL thickness is important for preventing adhesion of cells in the design of biomedical devices. In this study, a novel wall configuration with stenoses and bypass channels is proposed to increase the CFL thickness. We found that the presence of bypass channels modified the spatial distribution of cells and substantially increased the CFL downstream of the stenosis. A single-bypass geometry with 5% hematocrit (Hct) blood flow showed a 1.7μm increase in CFL thickness compared to without the bypass. In the case of three bypass channels, a 3μm increase in CFL thickness was observed. The CFL enhancement was observed up to 10% Hct, but no significant enhancement of CFL was indicated for 20% Hct blood flow. The mechanism of the CFL enhancement was investigated using a numerical simulation of the flow field. The results showed that the distance between each streamline and the corner of the stenosis compared with size of RBC was important parameter in regulating CFL thickness. These results show the potential of the proposed mechanism to prevent adhesion of cells to biomedical devices. PMID:26803337

  13. Rib fracture patterns predict thoracic chest wall and abdominal solid organ injury.

    PubMed

    Al-Hassani, Ammar; Abdulrahman, Husham; Afifi, Ibrahim; Almadani, Ammar; Al-Den, Ahmed; Al-Kuwari, Abdulaziz; Recicar, John; Nabir, Syed; Maull, Kimball I

    2010-08-01

    Blunt trauma patients with rib fractures were studied to determine whether the number of rib fractures or their patterns were more predictive of abdominal solid organ injury and/or other thoracic trauma. Rib fractures were characterized as upper zone (ribs 1 to 4), midzone (ribs 5 to 8), and lower zone (ribs 9 to 12). Findings of sternal and scapular fractures, pulmonary contusions, and solid organ injures (liver, spleen, kidney) were characterized by the total number and predominant zone of ribs fractured. There were 296 men and 14 women. There were 38 patients with scapular fracture and 19 patients with sternal fractures. There were 90 patients with 116 solid organ injuries: liver (n = 42), kidney (n = 27), and spleen (n = 47). Lower rib fractures, whether zone-limited or overlapping, were highly predictive of solid organ injury when compared with upper and midzones. Scapular and sternal fractures were more common with upper zone fractures and pulmonary contusions increased with the number of fractured ribs. Multiple rib fractures involving the lower ribs have a high association with solid organ injury, 51 per cent in this series. The increasing number of rib fractures enhanced the likelihood of other chest wall and pulmonary injuries but did not affect the incidence of solid organ injury. PMID:20726423

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

    PubMed

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

    2016-08-01

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

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

    PubMed

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

    2016-08-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  18. Application of "cinch/tie" technique to robotic-assisted nephropexy for posterior abdominal wall fixation.

    PubMed

    Castle, Scott M; Karnjanawanichkul, Watid; Leveillee, Raymond J

    2012-06-01

    Nephropexy remains standard for symptomatic nephroptosis, and several minimally-invasive techniques have been described. Triangulation sutures placed between the abdominal wall and the renal capsule are often difficult to tie tightly due to the confined working space. We propose a technique modification to fixate the kidney utilizing the da Vinci Surgical System robot and Lapra-Ty absorbable suture clips. Four female patients with symptomatic nephroptosis diagnosed via kidney hypermobility demonstrated on intravenous urography (IVU) underwent robotic-assisted laparoscopic nephropexy (RALNP) from February 2008 to April 2010. After complete mobilization and stripping of perirenal fat, several 0 Vicryl sutures were placed in a "figure of eight" fashion and tied loosely. Subsequently we utilized a Lapra-Ty to tighten the stitch serially and fixate the kidney. The mean age was 46 years (43-52); one patient underwent simultaneous pyeloplasty and one underwent partial nephrectomy in the ipsilateral kidney. There were no intraoperative complications and two postoperative complications, both Clavien grade I. All patients were asymptomatic postoperatively at a mean follow-up of 9.2 months (1-28), and had no evidence of kidney hypermobility on upright IVU or diuretic renal scintigraphy (RS) scan at 6 weeks postoperatively. RALNP is a viable option in the treatment of symptomatic nephroptosis. Secure placement of several "pexing" sutures helps to ensure appropriate security of these itinerant kidneys. Our technique modification corrects kidney hypermobility while improving symptoms related to nephroptosis. PMID:27628279

  19. 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

  20. 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.

  1. Pancreatic pseudocysts presenting as thick-walled renal and perinephric cysts.

    PubMed

    Lilienfeld, R M; Lande, A

    1976-02-01

    Posterior extension of a pancreatic pseudocyst should be considered in the differential diagnosis of a thick-walled renal or perinephric cyst seen on infusion pyelography with tomography. Opacification of the wall of a pancreatic pseudocyst by this technique has not been reported previously and lack of knowledge of this possibility can lead to mistaken diagnosis and the possibility of an unnecessary exploratory operation, particularly when angiography is inconclusive and a gastrointestinal series is negative or equivocal. The mechanism of opacification of the wall of a pancreatic pseudocyst is discussed. Parasitization of the renal capsular arteries by a pancreatic pseudocyst can further compound the difficulty of diagnosis.

  2. 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.

  3. A Comparison of Vaginal Pressures and Abdominal Muscle Thickness According to Childbirth Delivery Method during the Valsalva Maneuver

    PubMed Central

    Kim, Haroo; Kak, Hwang-Bo; Kim, Boin

    2014-01-01

    [Purpose] The purpose of this study was to compare the effect of childbirth delivery method on vaginal pressure and abdominal thickness during the Valsalva maneuver (VAL). [Subjects] Thirty healthy female volunteers (26–39 years of age) were selected for this research. Their delivery histories were: nulliparous 10, vaginal delivery 10, and Cesarean delivery 10. None of the participants had a history of incontinence. [Methods] In the crook-lying position, a perineometer probe was inserted into the vagina and the transducer was placed transversely on the right side of the body during the Valsalva maneuver. [Results] There were significant differences in the thickness of the transverses abdominis (TrA) between in all the groups rest and the Valsalva maneuver, and there were significant differences in the internus oblique (IO) in the nulliparous group. During the Valsalva maneuver, there were significant differences in the TrA between the nulliparous group and the vaginal delivery group, and there were significant differences in the IO between the nulliparous delivery group and the vaginal delivery group, and between the nulliparous group and the Cesarean section group. Delivery history changed vaginal pressure, and there were significant differences between the nulliparous group and the vaginal delivery group, and between the nulliparous group and the Cesarean delivery group. [Conclusion] Pregnancy and delivery method may affect pelvic floor and abdominal muscles during the Valsalva maneuver. PMID:24707104

  4. Fatigue life improvement of an autofrettage thick-walled pressure vessel with an external groove

    NASA Astrophysics Data System (ADS)

    Koh, Seung K.; Stephens, Ralph I.

    1992-01-01

    This report presents an investigation into a fatigue life improvement of an autofrettaged thick-walled pressure vessel with an external groove subjected to pulsating internal pressure, along with mean strain and mean stress effects on strain-controlled low cycle fatigue behavior. Linear elastic stress analysis of an autofrettaged thick-walled pressure vessel with an external groove is done using a finite element method. Autofrettage loading is performed using a thermal loading analogy. Change of external groove geometry is made using a quasi-optimization technique and finite element method to achieve longer fatigue life by relieving the stress concentration at the groove root. Surface treatment using shot peening is employed to produce compressive residual stresses at the vulnerable surface of the groove root to counteract the high tensile stresses. An evaluation of the fatigue life of an autofrettaged thick-walled pressure vessel with an external groove is done through a series of simulation fatigue tests using C-shaped specimens taken from the thick-walled pressure vessel.

  5. Wall-Thickness Dependence of Cooling-Induced Deformation of Polystyrene Spherical Shells

    SciTech Connect

    Endo, T.; Kobayashi, N.; Goto, K.; Yasuda, M.; Fujima, Y.

    2003-05-15

    Experiments on the wall-thickness dependence of the cooling-induced deformation (CID) of polystyrene (PS) spherical shells were carried out. For the experiments, the PS shells were fabricated by the density-matched emulsion method using the hand-shaken microencapsulation technique. The number-averaged and weight-averaged molecular weights of the PS were M{sub n} 1.1 x 10{sup 5} and M{sub w} = 4.0 x 10{sup 5}, respectively. The diameter of the PS shells was {approx}400-550 {mu}m. To investigate the wall-thickness dependence of the CID, the wall thickness of the PS shells was varied between 5 and 60 {mu}m. In the experiments, the PS shells were cooled by using liquid nitrogen, and their images were captured at 0 and -190 deg. C. For the investigation of the CID, two shapes of each shell that were measured at 0 and -190 deg. C were compared. The thinner PS shells showed larger CID. The maximum deformation was almost 1% of the outer radius when the shell aspect ratio (outer radius)/(wall thickness) was higher than 20. The repeatability of the CID was studied, and the results implied that residual stress in the PS shells had an influence on the CID.

  6. Automatic Thickness and Volume Estimation of Sprayed Concrete on Anchored Retaining Walls from Terrestrial LIDAR Data

    NASA Astrophysics Data System (ADS)

    Martínez-Sánchez, J.; Puente, I.; GonzálezJorge, H.; Riveiro, B.; Arias, P.

    2016-06-01

    When ground conditions are weak, particularly in free formed tunnel linings or retaining walls, sprayed concrete can be applied on the exposed surfaces immediately after excavation for shotcreting rock outcrops. In these situations, shotcrete is normally applied conjointly with rock bolts and mesh, thereby supporting the loose material that causes many of the small ground falls. On the other hand, contractors want to determine the thickness and volume of sprayed concrete for both technical and economic reasons: to guarantee their structural strength but also, to not deliver excess material that they will not be paid for. In this paper, we first introduce a terrestrial LiDAR-based method for the automatic detection of rock bolts, as typically used in anchored retaining walls. These ground support elements are segmented based on their geometry and they will serve as control points for the co-registration of two successive scans, before and after shotcreting. Then we compare both point clouds to estimate the sprayed concrete thickness and the expending volume on the wall. This novel methodology is demonstrated on repeated scan data from a retaining wall in the city of Vigo (Spain), resulting in a rock bolts detection rate of 91%, that permits to obtain a detailed information of the thickness and calculate a total volume of 3597 litres of concrete. These results have verified the effectiveness of the developed approach by increasing productivity and improving previous empirical proposals for real time thickness estimation.

  7. 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…

  8. 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.

  9. Intrathoracic Desmoid Tumor Presenting as Multiple Lung Nodules 13 Years after Previous Resection of Abdominal Wall Desmoid Tumor.

    PubMed

    Koo, Gun Woo; Chung, Sung Jun; Kwak, Joo Hee; Oh, Chang Kyo; Park, Dong Won; Kwak, Hyeon Jung; Moon, Ji-Yong; Kim, Sang-Heon; Sohn, Jang Won; Yoon, Ho Joo; Shin, Dong Ho; Park, Sung Soo; Oh, Young-Ha; Pyo, Ju Yeon; Kim, Tae-Hyung

    2015-07-01

    Desmoid tumors are rare soft tissue tumors considered to have locally infiltrative features without distant metastasis until now. Although they are most commonly intraabdominal, very few cases have extra-abdominal locations. The origin of intrathoracic desmoid tumors is predominantly the chest wall with occasional involvement of pleura. True intrathoracic primary desmoid tumors with no involvement of the chest wall or pleura are extremely rare. We recently experienced a case of true intrathoracic desmoid tumor presenting as multiple lung nodules at 13 years after resection of a previous intraabdominal desmoid tumor.

  10. Room temperature synthesis of indium tin oxide nanotubes with high precision wall thickness by electroless deposition.

    PubMed

    Boehme, Mario; Ionescu, Emanuel; Fu, Ganhua; Ensinger, Wolfgang

    2011-01-01

    Conductive nanotubes consisting of indium tin oxide (ITO) were fabricated by electroless deposition using ion track etched polycarbonate templates. To produce nanotubes (NTs) with thin walls and small surface roughness, the tubes were generated by a multi-step procedure under aqueous conditions. The approach reported below yields open end nanotubes with well defined outer diameter and wall thickness. In the past, zinc oxide films were mostly preferred and were synthesized using electroless deposition based on aqueous solutions. All these methods previously developed, are not adaptable in the case of ITO nanotubes, even with modifications. In the present work, therefore, we investigated the necessary conditions for the growth of ITO-NTs to achieve a wall thickness of around 10 nm. In addition, the effects of pH and reductive concentrations for the formation of ITO-NTs are also discussed.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. Wall energy and wall thickness of exchange-coupled rare-earth transition-metal triple layer stacks

    SciTech Connect

    Raasch, D.; Mathieu, C.

    1997-08-01

    The room-temperature wall energy {sigma}{sub w}=4.0{times}10{sup {minus}3}J/m{sup 2} of an exchange-coupled Tb{sub 19.6}Fe{sub 74.7}Co{sub 5.7}/Dy{sub 28.5}Fe{sub 43.2}Co{sub 28.3} double layer stack can be reduced by introducing a soft magnetic intermediate layer in between both layers exhibiting a significantly smaller anisotropy compared to Tb{endash}FeCo and Dy{endash}FeCo. {sigma}{sub w} will decrease linearly with increasing intermediate layer thickness, d{sub IL}, until the wall is completely located within the intermediate layer for d{sub IL}{ge}d{sub w}, where d{sub w} denotes the wall thickness. Thus, d{sub w} can be obtained from the plot {sigma}{sub w} versus d{sub IL}. We determined {sigma}{sub w} and d{sub w} on Gd{endash}FeCo intermediate layers with different anisotropy behavior (perpendicular and in-plane easy axis) and compared the results with data obtained from Brillouin light-scattering measurements, where exchange stiffness, A, and uniaxial anisotropy, K{sub u}, could be determined. With the knowledge of A and K{sub u}, wall energy and thickness were calculated and showed an excellent agreement with the magnetic measurements. A ten times smaller perpendicular anisotropy of Gd{sub 28.1}Fe{sub 71.9} in comparison to Tb{endash}FeCo and Dy{endash}FeCo resulted in a much smaller {sigma}{sub w}=1.1{times}10{sup {minus}3}J/m{sup 2} and d{sub w}=24nm at 300 K. A Gd{sub 34.1}Fe{sub 61.4}Co{sub 4.5} with in-plane anisotropy at room temperature showed a further reduced {sigma}{sub w}=0.3{times}10{sup {minus}3}J/m{sup 2} and d{sub w}=17nm. The smaller wall energy was a result of a different wall structure compared to perpendicular layers. {copyright} {ital 1997 American Institute of Physics.}

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

    PubMed Central

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

    2015-01-01

    Key Clinical Message 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

  17. 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.

  18. Abdominal hollowing and lateral abdominal wall muscles' activity in both healthy men & women: An ultrasonic assessment in supine and standing positions.

    PubMed

    Manshadi, Farideh Dehghan; Parnianpour, Mohamad; Sarrafzadeh, Javad; Azghani, Mahmood Reza; Kazemnejad, Anooshirvan

    2011-01-01

    The objective of this study was to investigate the effects of Abdominal Hollowing (AH) maneuver on External Oblique (EO), Internal Oblique (IO) and Transversus Abdominis (TrA) muscles in both healthy men and women during the two postures of supine and upright standing. The study was conducted on 43 asymptomatic volunteers (22 males and 21 females) aged 19-44 (27.8±6.4) years. Rehabilitative Ultrasonic Imaging (RUSI) was simultaneously performed to measure muscle thickness in both rest and during AH maneuvers while activation of the TrA during AH was controlled by Pressure Biofeedback (PBF) device. Mixed-model ANOVA with repeated measures design, and Pearson correlation tests were used to analyze the data. Muscle thickness of all muscles was significantly higher for male subjects (F>6.2, p<0.017). The interaction effect of gender and muscle status was significant only for IO (F=7.458, p=0.009) indicating that AH maneuver increased the thickness of IO in men. Interaction effect of posture and muscle status on muscular thickness indicated that changing position only affects the resting thickness of TrA (F=5.617, p=0.023). Standing posture significantly affected the TrA contraction ratio (t=3.122, p=0.003) and TrA preferential activation ratio (t=2.76, p=0.008). There was no relationship between age and muscle thickness (r=0.262, p=0.09). The PBF has been introduced as a clinical and available device for monitoring TrA activity, while RUSI showed that both TrA and IO muscles had activated after AH maneuver. We recommend performing further investigations using electromyography and RUSI simultaneously at more functional postures such as upright standing.

  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. 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.

  1. Alveolar Antral Artery: Does its Diameter Correlate with Maxillary lateral wall Thickness in Dentate Patients?

    PubMed Central

    Rahpeyma, Amin; Khajehahmadi, Saeedeh; Amini, Parvin

    2014-01-01

    Introduction: Knowledge of the presence of the alveolar antral artery in the lateral maxillary sinus wall is essential for surgeons who operate in this region. The purpose of this study was to investigate the correlation between alveolar antral artery diameter and lateral maxillary bony wall thickness in dentate patients. Materials and Methods: Thirty five Cone-Beam Computed Tomography (CBCT) scans from 35 dentate patients were selected in coronal sections in three locations; second premolar (P2), first molar (M1), and second molar (M2). The presence of the alveolar antral artery in each situation was determined and the bone thickness in the region of alveolar antral artery was measured perpendicular to the lateral wall of the maxilla. Results: The alveolar antral artery was present in 67.1% CBCTs. The difference between the alveolar antral artery diameter was only significant in the first and second molar area (P=0.039).There were significant differences between bone thickness in three locations, with the thickest bone in the first molar area followed by the second molar and second premolar, respectively. The correlation coefficient showed that there is a positive correlation between bone thickness and alveolar antral artery diameter. Conclusion: This study showed that the thicker the bones in dentate patients, the greater the chance of interference with the large caliber intra-osseous alveolar antral artery. PMID:25009806

  2. 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 cm×4 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 5–10 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

  3. 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.

  4. High Power Laser Beam Welding of Thick-walled Ferromagnetic Steels with Electromagnetic Weld Pool Support

    NASA Astrophysics Data System (ADS)

    Fritzsche, André; Avilov, Vjaceslav; Gumenyuk, Andrey; Hilgenberg, Kai; Rethmeier, Michael

    The development of modern high power laser systems allows single pass welding of thick-walled components with minimal distortion. Besides the high demands on the joint preparation, the hydrostatic pressure in the melt pool increases with higher plate thicknesses. Reaching or exceeding the Laplace pressure, drop-out or melt sagging are caused. A contactless electromagnetic weld support system was used for laser beam welding of thick ferromagnetic steel plates compensating these effects. An oscillating magnetic field induces eddy currents in the weld pool which generate Lorentz forces counteracting the gravity forces. Hysteresis effects of ferromagnetic steels are considered as well as the loss of magnetization in zones exceeding the Curie temperature. These phenomena reduce the effective Lorentz forces within the weld pool. The successful compensation of the hydrostatic pressure was demonstrated on up to 20 mm thick plates of duplex and mild steel by a variation of the electromagnetic power level and the oscillation frequency.

  5. A novel method for endoscopic perforation management by using abdominal exploration and full-thickness sutured closure

    PubMed Central

    Kumar, Nitin; Thompson, Christopher C.

    2016-01-01

    Background Perforation of the GI tract during endoscopy can result in significant morbidity and mortality. Early recognition and immediate management of endoscopic perforation are essential to optimize outcome. Larger perforations, defects with complex geometry, and those complicated by leakage of luminal contents have traditionally required surgical management. Objective To assess the feasibility of a new method for managing complex perforations that incorporates abdominal exploration and endoscopic sutured closure. Design Case series. Setting Tertiary care center. Patients Two patients with large, complicated perforations and peritoneal contamination. Interventions Endoscopic exploration of abdomen with angiocatheter placement under direct visualization, management of leaked luminal contents, and full-thickness sutured defect closure. Results Endoscopic abdominal exploration through the perforation site allowed safe placement of an angiocatheter for management of pneumoperitoneum, inspection for injury that may warrant surgical management, and removal of leaked luminal contents. Endoscopic sutured closure allowed safe and robust perforation management. Repair of gastrojejunal anastomotic perforation required 2 sutures and 63 minutes. Repair of gastric perforation required 4 sutures and 48 minutes. Patients had successful endoscopic defect closure confirmed by an upper GI series and were discharged 1 day later. Limitations Report of a new method in 2 patients performed at tertiary care center. Conclusions We demonstrate successful management of complex perforations with peritoneal contamination by incorporating endoscopic exploration and sutured closure with standard treatment measures. Traditional practice would have directed these patients to surgical management, which introduces additional morbidity and cost. A means for safe and broad implementation of these techniques should be evaluated. PMID:24721517

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

    PubMed Central

    2012-01-01

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

  7. Sensitivity of dual-wall structures under hypervelocity impact to multi-layer thermal insulation thickness and placement

    NASA Technical Reports Server (NTRS)

    Schonberg, William P.

    1993-01-01

    Results are presented from an experimental study in which Al dual-wall structures were tested, under various high-speed impact conditions, with a view to the effect of multilayer insulation thickness and location on perforation resistance. Attention is given to comparisons of the damage sustained by dual-wall systems with multilayer insulation blankets of various thicknesses and at various locations within the dual-wall system, under comparable impact loading conditions. The placement of the insulation has a significant effect on the ballistic limit of the dual-wall structures considered, while reducing insulation thickness by as much as a third did not.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. Increased arterial wall stiffness and thickness in medium-sized arteries in patients with insulin-dependent diabetes mellitus.

    PubMed

    Christensen, T; Neubauer, B

    1988-01-01

    By means of ultrasonography, arterial wall stiffness, arterial wall thickness, and the elastic modulus of the common femoral artery were estimated in a group of 19 young insulin-dependent diabetics. The ultrasound technique for determination of these parameters is described as well as the echo-anatomy of the arterial wall. In accordance with a previous investigation a significant rise in arterial wall stiffness was found. Furthermore, there was a highly significant correlation between the stiffness and the thickness of the arterial wall. The elastic modulus also correlated to the stiffness. It is concluded that the diabetic macroangiopathy is characterized by an increased stiffness of the arterial wall caused by increased thickness as well as by progressive alterations of the elastic characteristics of the wall tissue. Possible pathogenetic reasons are discussed.

  14. Influence of surrounding wall thickness on the fatigue resistance of molars restored with ceramic inlay.

    PubMed

    Shibata, Shizuma; Gondo, Renata; Araújo, Élito; Mello Roesler, Carlos Rodrigo de; Baratieri, Luiz Narciso

    2014-01-01

    The purpose of this study was to evaluate the influence of buccal and lingual wall thickness on the fatigue resistance of molars restored with CAD/CAM ceramic inlays. Forty human third molars were selected and divided into 4 groups, according to the remaining surrounding wall thickness chosen for inlay preparation (n=10): G1, 2.0 mm; G2, 1.5 mm; G3, 1.0 mm; G4, 0.5 mm. All inlays were made from feldspathic ceramic blocks by a CAD/CAM system, and cemented adhesively. After 1 week stored in distilled water at 37 °C, the specimens were subjected to fatigue testing under the following protocol: 5Hz; pre-load of 200 N for 5,000 cycles, followed by increasing loads of 400, 600, 800, 1000, 1200 and 1400 N for 30,000 cycles each. The specimens were cycled until failure or completion of 185,000 cycles. The survival rate of the groups was compared using the Kaplan-Meier survival curves (p>0.05). All specimens withstood the fatigue protocol (185,000 cycles), representing a 100% survival rate. The Kaplan-Meier survival curves showed no difference between groups. It can be concluded that the remaining tooth wall thickness did not influence the fatigue resistance of molars restored with CAD/CAM ceramic inlays.

  15. Quantum confinement of crystalline silicon nanotubes with nonuniform wall thickness: Implication to modulation doping

    NASA Astrophysics Data System (ADS)

    Yan, Binghai; Zhou, Gang; Zeng, Xiao Cheng; Wu, Jian; Gu, Bing-Lin; Duan, Wenhui

    2007-09-01

    First-principles calculations of crystalline silicon nanotubes (SiNTs) show that nonuniformity in wall thickness can cause sizable variation in the band gap as well as notable shift in the optical absorption spectrum. A unique quantum confinement behavior is observed: the electronic wave functions of the valence band maximum and conduction band minimum are due mainly to atoms located in the thicker side of the tube wall. This is advantageous to spatially separate the doping impurities from the conducting channel in doped SiNTs. Practically, the performance of the SiNT-based transistors may be substantially improved by selective p /n doping in the thinner side of the tube wall in the spirit of modulation doping.

  16. Polarizabilities of an annular cut in the wall of an arbitrary thickness

    NASA Astrophysics Data System (ADS)

    Kurennoy, S. S.

    1996-07-01

    The electric and magnetic polarizabilities of an aperture are its important characteristics in the theory of aperture coupling and diffraction of EM waves. The beam coupling impedances due to a small discontinuity on the chamber wall of an accelerator can also be expressed in terms of the polarizabilities of the discontinuity. The polarizabilities are geometrical factors which can be found by solving a static (electric or magnetic) problem. However, they are known in an explicit analytical form only for a few simple-shaped discontinuities, such as an elliptic hole in a thin wall. In the present paper the polarizabilities of a ring-shaped cut in the wall of an arbitrary thickness are studied using a combination of analytical, variational and numerical methods. The results are applied to estimate the coupling impedances of button-type beam position monitors.

  17. Carotid wall stress calculated with continuous intima-media thickness assessment using B-mode ultrasound

    NASA Astrophysics Data System (ADS)

    Pascaner, A. F.; Craiem, D.; Casciaro, M. E.; Danielo, R.; Graf, S.; Guevara, E.

    2016-04-01

    Cardiovascular risk is normally assessed using clinical risk factors but it can be refined using non-invasive infra-clinical markers. Intima-Media Thickness (IMT) is recognized as an early indicator of cardiovascular disease. Carotid Wall Stress (CWS) can be calculated using arterial pressure and carotid size (diameter and IMT). Generally, IMT is measured during diastole when it reaches its maximum value. However, it changes during the cardiac cycle and a time-dependant waveform can be obtained using B-mode ultrasound images. In this work we calculated CWS considering three different approaches for IMT assessment: (i) constant IMT (standard diastolic value), (ii) estimated IMT from diameter waveform (assuming a constant cross-sectional wall area) and (iii) continuously measured IMT. Our results showed that maximum wall stress depends on the IMT estimation method. Systolic CWS progressively increased using the three approaches (p<0.024). We conclude that maximum CWS is highly dependent on wall thickness and accurate IMT measures during systole should be encouraged.

  18. 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.

  19. Association Between the Lateral Wall Thickness of the Maxillary Sinus and the Dental Status: Cone Beam Computed Tomography Evaluation

    PubMed Central

    Khajehahmadi, Saeedeh; Rahpeyma, Amin; Hoseini Zarch, Seyed Hosein

    2014-01-01

    Background: Assessment of the lateral wall thickness of the maxillary sinus is very important in decision making for many surgical interventions. The association between the thickness of the lateral wall of the maxillary sinus and the dental status is not well identified. Objectives: To compare the thickness of the lateral wall of the maxillary sinus in individuals with and without teeth to determine if extraction of the teeth can lead to a significant reduction in the thickness of the maxillary sinus lateral wall or not. Patients and Methods: In a retrospective study on fifty patients with an edentulous space, the thickness of the lateral wall of the maxillary sinus,one centimeter above the sinus floor in the second premolar (P2), first molar (M1) and second molar (M2) areas was determined by cone beam computed tomography scans(CBCTs) and a digital ruler in Romexis F software (Planmeca Romexis 2.4.2.R) and it was compared with values measured in fifty dentated individuals. Three way analysis of variance was applied for comparison after confirmation of the normal distribution of data. Results: The mean of the wall thickness in each of these points was lower in patients with edentulous spaces; however it was not significant. There was no association between gender and the thickness of the lateral wall of the maxillary sinus, but location was associated with different thicknesses. Conclusions: The differences in the thickness based on the location and dental status necessitates assessment of the wall thickness of the maxillary sinus in addition to the current evaluation of bone thickness between the sinus floor and the edentulous crest before maxillary sinus surgery. PMID:24693302

  20. [Effect of jiang-zhi jian-fei yao on gastro-intestinal movement and adipose cell of abdominal wall].

    PubMed

    Jin, H M; Jiao, D H

    1994-04-01

    Jiang-Zhi Jian-Fei Yao (JZJFY), an obesity-reducing drug, its active principle is the refined Rhubarb, the mechanism of its obesity-reducing effect was studied. JZJFY was injected intragastrically. The results showed that there was no significant increased of body weight, but a reduction of food intake, prolongation of stomach evacuation time, acceleration of intestinal movement 6 days after medication in rats. Meanwhile the adipose cells in abdominal wall were varied in size, and with Sudan III stain the color of adipose cells was light. Authors suggest that the obesity-reducing effect of JZJFY was relevant to above-mentioned changes.

  1. Determination of right ventricular wall thickness in systole and diastole. Echocardiographic and necropsy correlation in 32 patients.

    PubMed Central

    Prakash, R

    1978-01-01

    To show that right ventricular wall thickness (RVWT) measurements can be made with precision by echocardiography, we correlated these measurements with those obtained at necropsy in 32 terminal patients. The correlation between the echocardiographic diastolic right ventricular wall thickness (mean 4.0 +/- 1.62 mm) and the necropsy measurement (mean 4.3 +/- 1.52 mm) was good (r = 0.83) in all 32 patients with normal or increased right ventricular wall thickness at necropsy. In 19 patients without necropsy evidence of right ventricular hypertrophy (RVWT less than or equal to 4 mm), the mean diastole and systolic right ventricular wall thickness were 3.0 +/- 0.92 mm and 5.1 +/- 1.64 mm, respectively. In 13 patients with necropsy evidence of right ventricular hypertrophy (RVWT greater than or equal to 5 mm), the mean diastolic and systolic right ventricular wall thicknesses were 5.3 +/- 1.56mm and 8.2 +/- 1.88 mm, respectively. We conclude that technically satisfactory echocardiograms of the right ventricular wall thicknesses. Echocardiography can reliably estimate the diastolic wall thickness and may be helpful in the evaluation of right ventricular hypertrophy. Images PMID:718765

  2. 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

  3. 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

  4. Out-of-Plane Bending of Beam-Wall Joints Based on Elastic Medium Thick Plate Theory

    NASA Astrophysics Data System (ADS)

    Zhifei, Shi; Shuling, Yang

    2011-01-01

    The out-of-plane response of beam-wall joints is studied in the present paper. The governing equations of shear walls obtained by using the orthotropic elastic medium thick plate theory are solved. Additionally, different reinforcing ratios for shear walls in different directions are considered. It is also found that reinforced shear walls can be simplified as isotropic walls no matter whether the reinforcing ratio in both directions is the same or not for most engineering structures. In view of this, the out-of-plane response of beam-wall joints is investigated based on the isotropic medium thick plate theory and the effects of geometrical parameters of the joints on the responses of the shear walls are discussed in detail. For further simplification, the equivalent frame model is introduced and a very simple formula to determine the equivalent width is suggested for practical applications.

  5. Continued research on the strain to failure of thick-walled cylinders subjected to internal pressure

    SciTech Connect

    Roach, D.P.; Priddy, T.G.

    1990-01-01

    The determination of the fully plastic response and pressure limit of a pressure vessel is of considerable importance in design. In-house experience in weapon development, new aerospace applications and autofrettage operations all require in-depth knowledge of the strength of high pressure containment structures. This paper presents additional results to support the strain-to-failure analysis of thick-walled cylindrical vessels. Both aluminum and steel, with material properties ranging from ductile to brittle, were tested at stress levels through plastic and strain hardening ranges to fracture. From these tests, the pressure-expansion and through thickness yielding characteristics were determined for these specimens. The critical effective plastic strain depends on the level of tensile stress triaxiality which varies through the wall thickness. It is shown that the proposed strain-to-failure criterion is based on this triaxiality of stress in the critical region and can be used to predict the complete pressure versus strain relations and maximum pressure for the test cylinders. 17 refs., 12 figs.

  6. 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

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

    PubMed

    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).

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

    PubMed

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

    2012-08-01

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

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

    SciTech Connect

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

    2007-05-01

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

  10. Impaired Gallbladder Motility and Increased Gallbladder Wall Thickness in Patients with Nonalcoholic Fatty Liver Disease

    PubMed Central

    Colak, Yasar; Bozbey, Gulcin; Erim, Tolga; Caklili, Ozge Telci; Ulasoglu, Celal; Senates, Ebubekir; Mutlu, Hasan Huseyin; Mesci, Banu; Doğan, Mehmet Sait; Tasan, Guralp; Enc, Feruze Yilmaz; Tuncer, Ilyas

    2016-01-01

    Background/Aims Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease worldwide. Along with the increase in the incidence of NAFLD and associated obesity, an increase in gallbladder disease (GD) has been noted. This has led to the identification of a new disease entity called fatty GD. There is a gap in the literature on the dynamics of gallbladder function in patients with NAFLD. Methods An observational case-control study, a total of 50 patients with biopsy proven NAFLD without gallbladder stone/sludge and 38 healthy comparison subjects were enrolled. Fasting, postprandial gallbladder volumes (PGV), gallbladder ejection fraction (GEF), and fasting gallbladder wall thickness (FGWT) were measured by real-time 2-dimensional ultrasonography. Results Fasting gallbladder wall thickness, fasting gallbladder volumes and PGV were significantly higher in patients with NAFLD than control subjects (P < 0.001, P = 0.006, and P < 0.001, respectively). Gallbladder ejection fraction was significantly lower in the NAFLD group than the controls (P = 0.008). The presence of NAFLD was an independent predictor for GEF, PGV, and FGWT. Also, steatosis grade was an independent predictor for GEF, and GEF was significantly lower in the nonalcoholic steatohepatitis (NASH) subgroup than the controls. Conclusions Gallbladder dysfunction and increase in gallbladder wall thickness exists in asymptomatic (without stone/sludge and related symptoms) patients with NAFLD and are useful in identifying fatty GD. Measurement of these variables in NAFLD patients may be useful in identifying those at higher risk for GD. PMID:26932908

  11. 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.

  12. The importance of ultrasonographic measurement of peritoneal wall thickness in pediatric chronic peritoneal dialysis patients.

    PubMed

    Yavaşcan, Önder; Aksu, Nejat; Alparslan, Caner; Sarıtaş, Serdar; Elmas, Cengiz Han; Eraslan, Ali Nihat; Duman, Soner; Mir, Sevgi

    2015-04-01

    Loss of peritoneal function due to peritoneal fibrosing syndrome (PFS) is a major factor leading to treatment failure in chronic peritoneal dialysis (PD) patients. Although the precise biologic mechanisms responsible for these changes have not been defined, the general assumption is that alterations in peritoneal function are related to structural changes in the peritoneal membrane. Studies of the peritoneal membrane by non-invasive ultrasonography (US) in chronic PD patients are limited. The aim of the present study is to assess the relationship between functional parameters of peritoneum and peritoneal thickness measured by US in children treated by chronic PD. We recruited two groups of patients: 23 subjects (13 females, 10 males) on chronic PD (patient group) and 26 (7 females, 19 males) on predialysis out-patient follow-up (creatinine clearance: 20-60 mL/min/1.73 m(2)) (control group). Age, sex, weight, height, body mass index (BMI), chronic PD duration, episodes of peritonitis and the results of peritoneal equilibration test (PET) were recorded. Hemoglobin (Hb), blood pressure (BP), left ventricular mass index (LVMI) and renal osteodystrophy (ROD) parameters were also obtained. The thickness of the parietal peritoneum was measured by trans-abdominal US in all children. Statistical analyses were performed by using Student's t and Pearson's correlation tests. Mean peritoneal thickness in chronic PD patients (1028.26 ± 157.26 μm) was significantly higher than control patients (786.52 ± 132.33). Mean peritoneal thickness was significantly correlated with mean body height (R(2) = 0.93, p < 0.05), BMI (R(2) = 0.25, p < 0.05), chronic PD duration (R(2) = 0.64, p < 0.05), episodes of peritonitis (R(2) = 0.93, p < 0.05), D/Pcreatinine (R(2) = 0.76, p < 0.05) and D4/D0glucose (R(2) = 0.81, p < 0.05). No correlation was found between peritoneal thickness and Hb, BP, LVMI and ROD parameters. In conclusion

  13. The importance of ultrasonographic measurement of peritoneal wall thickness in pediatric chronic peritoneal dialysis patients.

    PubMed

    Yavaşcan, Önder; Aksu, Nejat; Alparslan, Caner; Sarıtaş, Serdar; Elmas, Cengiz Han; Eraslan, Ali Nihat; Duman, Soner; Mir, Sevgi

    2015-04-01

    Loss of peritoneal function due to peritoneal fibrosing syndrome (PFS) is a major factor leading to treatment failure in chronic peritoneal dialysis (PD) patients. Although the precise biologic mechanisms responsible for these changes have not been defined, the general assumption is that alterations in peritoneal function are related to structural changes in the peritoneal membrane. Studies of the peritoneal membrane by non-invasive ultrasonography (US) in chronic PD patients are limited. The aim of the present study is to assess the relationship between functional parameters of peritoneum and peritoneal thickness measured by US in children treated by chronic PD. We recruited two groups of patients: 23 subjects (13 females, 10 males) on chronic PD (patient group) and 26 (7 females, 19 males) on predialysis out-patient follow-up (creatinine clearance: 20-60 mL/min/1.73 m(2)) (control group). Age, sex, weight, height, body mass index (BMI), chronic PD duration, episodes of peritonitis and the results of peritoneal equilibration test (PET) were recorded. Hemoglobin (Hb), blood pressure (BP), left ventricular mass index (LVMI) and renal osteodystrophy (ROD) parameters were also obtained. The thickness of the parietal peritoneum was measured by trans-abdominal US in all children. Statistical analyses were performed by using Student's t and Pearson's correlation tests. Mean peritoneal thickness in chronic PD patients (1028.26 ± 157.26 μm) was significantly higher than control patients (786.52 ± 132.33). Mean peritoneal thickness was significantly correlated with mean body height (R(2) = 0.93, p < 0.05), BMI (R(2) = 0.25, p < 0.05), chronic PD duration (R(2) = 0.64, p < 0.05), episodes of peritonitis (R(2) = 0.93, p < 0.05), D/Pcreatinine (R(2) = 0.76, p < 0.05) and D4/D0glucose (R(2) = 0.81, p < 0.05). No correlation was found between peritoneal thickness and Hb, BP, LVMI and ROD parameters. In conclusion

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

    PubMed

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

    2015-09-28

    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.

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

    PubMed

    Suleiman, Nergis Nina; Sandberg, Lars Johan Marcus

    2016-07-01

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

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

    PubMed Central

    Suleiman, Nergis Nina

    2016-01-01

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

  17. Effect of subcooling and wall thickness on pool boiling from downward-facing curved surfaces in water

    SciTech Connect

    El-Genk, M.S.; Glebov, A.G.

    1995-09-01

    Quenching experiments were performed to investigate the effects of water subcooling and wall thickness on pool boiling from a downward-facing curved surface. Experiments used three copper sections of the same diameter (50.8 mm) and surface radius (148 mm), but different thickness (12.8, 20 and 30 mm). Local and average pool boiling curves were obtained at saturation and 5 K, 10 K, and 14 K subcooling. Water subcooling increased the maximum heat flux, but decreased the corresponding wall superheat. The minimum film boiling heat flux and the corresponding wall superheat, however, increased with increased subcooling. The maximum and minimum film boiling heat fluxes were independent of wall thickness above 20 mm and Biot Number > 0.8, indicating that boiling curves for the 20 and 30 thick sections were representative of quasi steady-state, but not those for the 12.8 mm thick section. When compared with that for a flat surface section of the same thickness, the data for the 12.8 mm thick section showed significant increases in both the maximum heat flux (from 0.21 to 0.41 MW/m{sup 2}) and the minimum film boiling heat flux (from 2 to 13 kW/m{sup 2}) and about 11.5 K and 60 K increase in the corresponding wall superheats, respectively.

  18. Quantitative Analysis of Intraventricular Dyssynchrony Using Wall Thickness by Multidetector Computed Tomography

    PubMed Central

    Truong, Quynh A.; Singh, Jagmeet P.; Cannon, Christopher P.; Sarwar, Ammar; Nasir, Khurram; Auricchio, Angelo; Faletra, Francesco F.; Sorgente, Antonio; Conca, Cristina; Moccetti, Tiziano; Handschumacher, Mark; Brady, Thomas J.; Hoffmann, Udo

    2009-01-01

    OBJECTIVES We sought to determine the feasibility of cardiac computed tomography (CT) to detect significant differences in the extent of left ventricular dyssynchrony in heart failure (HF) patients with wide QRS, HF patients with narrow QRS, and age-matched controls. BACKGROUND The degree of mechanical dyssynchrony has been suggested as a predictor of response to cardiac resynchronization therapy. There have been no published reports of dyssynchrony assessment with the use of CT. METHODS Thirty-eight subjects underwent electrocardiogram-gated contrast-enhanced 64-slice multidetector CT. The left ventricular endocardial and epicardial boundaries were delineated from short-axis images reconstructed at 10% phase increments of the cardiac cycle. Global and segmental CT dyssynchrony metrics that used changes in wall thickness, wall motion, and volume over time were assessed for reproducibility. We defined a global metric using changes in wall thickness as the dyssynchrony index (DI). RESULTS The DI was the most reproducible metric (interobserver and intraobserver intraclass correlation coefficients ≥0.94, p < 0.0001) and was used to determine differences between the 3 groups: HF-wide QRS group (ejection fraction [EF] 22 ± 8%, QRS 163 ± 28 ms), HF-narrow QRS (EF 26 ± 7%, QRS 96 ± 11 ms), and age-matched control subjects (EF 64 ± 5%, QRS 87 ± 9 ms). Mean DI was significantly different between the 3 groups (HF-wide QRS: 152 ± 44 ms, HF-narrow QRS: 121 ± 58 ms, and control subjects: 65 ± 12 ms; p < 0.0001) and greater in the HF-wide QRS (p < 0.0001) and HF-narrow QRS (p = 0.005) groups compared with control subjects. We found that DI had a good correlation with 2-dimensional (r = 0.65, p = 0.012) and 3-dimensional (r = 0.68, p = 0.008) echocardiographic dyssynchrony. CONCLUSIONS Quantitative assessment of global CT-derived DI, based on changes in wall thickness over time, is highly reproducible and renders significant differences between subjects most likely to

  19. An Approach for Patient-Specific Multi-domain Vascular Mesh Generation Featuring Spatially Varying Wall Thickness Modeling

    PubMed Central

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

    2015-01-01

    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 robust by handling 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; 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

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

    PubMed

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

    1996-03-01

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

  1. Effects of selective exercise for the deep abdominal muscles and lumbar stabilization exercise on the thickness of the transversus abdominis and postural maintenance

    PubMed Central

    Lee, Jung-seok; Kim, Tae-ho; Kim, Da-yeon; Shim, Jae-ho; Lim, Jin-yong

    2015-01-01

    [Purpose] The purpose of this study was to examine the effects of selective exercise for the deep abdominal muscles (SEDA) and lumbar stabilization exercise (LSE) on the thickness of the transversus abdominis and postural maintenance on an unstable base of support. [Subjects and Methods] The subjects of this study were 20 male and 10 female adults in their 20s without lumbar pain. They were equally and randomly assigned to a SEDA group and a LSE group. The thickness of the transversus abdominis was measured using ultrasound imaging during rest and drawing-in. The thickness of the transversus abdominis was measured when subjects raised their right and left legs while lying on a Swiss ball. [Results] Initially, there were no differences between the two groups. After the intervention, significant differences were observed in all parameters. A significant interaction between group and period was not found for any parameters. [Conclusion] In conclusion, both SEDA and LSE thickened the transversus abdominis, which is a deep abdominal muscle, thereby adjusting posture, and stabilizing the trunk. These exercises increased the thickness of the deep abdominal muscles. They are important exercises for improving the stability of athletes or patients who need postural adjustment. PMID:25729169

  2. Effects of selective exercise for the deep abdominal muscles and lumbar stabilization exercise on the thickness of the transversus abdominis and postural maintenance.

    PubMed

    Lee, Jung-Seok; Kim, Tae-Ho; Kim, Da-Yeon; Shim, Jae-Ho; Lim, Jin-Yong

    2015-02-01

    [Purpose] The purpose of this study was to examine the effects of selective exercise for the deep abdominal muscles (SEDA) and lumbar stabilization exercise (LSE) on the thickness of the transversus abdominis and postural maintenance on an unstable base of support. [Subjects and Methods] The subjects of this study were 20 male and 10 female adults in their 20s without lumbar pain. They were equally and randomly assigned to a SEDA group and a LSE group. The thickness of the transversus abdominis was measured using ultrasound imaging during rest and drawing-in. The thickness of the transversus abdominis was measured when subjects raised their right and left legs while lying on a Swiss ball. [Results] Initially, there were no differences between the two groups. After the intervention, significant differences were observed in all parameters. A significant interaction between group and period was not found for any parameters. [Conclusion] In conclusion, both SEDA and LSE thickened the transversus abdominis, which is a deep abdominal muscle, thereby adjusting posture, and stabilizing the trunk. These exercises increased the thickness of the deep abdominal muscles. They are important exercises for improving the stability of athletes or patients who need postural adjustment.

  3. On the Opening of Thick Walled Elastic Tubes: A Fluid-Structure Model for Acid Reflux

    NASA Astrophysics Data System (ADS)

    Ghosh, Sudip; Kahrilas, Peter

    2005-11-01

    A coupled fluid-structure mathematical model was developed to quantify rapid opening of thick-walled elastic tubes, a phenomenon underlying biological flows such as gastroesophageal reflux disease (GERD). The wall was modeled using non-linear finite deformation theory to predict space-time radial distention of an axisymmetric tube with luminal fluid flow. Anisotropic azimuthal and longitudinal muscle-induced stresses were incorporated, and interstitial material properties were assumed isotropic and linearly elastic. Fluid flow was modeled using lubrication theory with inertial correction. Opening and flow were driven by a specified inflow pressure and zero pressure gradient was specified at outflow. No-slip and surface force balance were applied at the fluid-wall interface. Viscoelasticity was modeled with ad hoc damping and the evolution of the tube geometry was predicted at mid-layer. A potentially important discovery was made when applied to studies of initiation of opening with GERD: while material stiffness is of minor consequence, small changes in resting lumen distension (˜2 mm diameter) may be a sensitive distinguishing feature of the disease.

  4. 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

  5. [A case of Paragonimiasis westermani with pleural effusion eight months after migrating subcutaneous induration of the abdominal wall].

    PubMed

    Mizuki, M; Mitoh, K; Miyazaki, E; Tsuda, T

    1992-06-01

    Patients with Paragonimiasis westermani show a typical ring form or nodular shadow on chest X-ray, cough, sputum, and hemosputum. Recently, case reports of Paragonimiasis westermani, accompanied by pneumothorax and pleural effusion, as for Paragonimiasis miyazakii, have been increasing. Paragonimus westermani often causes an ectopic infection in various organs such as the peritoneal cavity, pleural cavity, pericardium, liver, adrenal gland and brain. Cutaneous paragonimiasis is considered one of the typical forms of ectopic infection in its earlier phase, but a few unexpected cases of cutaneous Paragonimiasis westermani have also been reported. A 68-year old man, who had never eaten fresh-water crab or raw sliced meat of wild boar, noticed subcutaneous induration of the abdominal wall. The induration had been gradually moving upwards and to the right from the infraumbilical region for over 20 days, and then disappeared at the right upper lateral abdominal wall. Eight months later, he developed severe pain in the right lower chest, and a chest X-ray showed right pleural effusion. Laboratory examinations revealed eosinophilia (WBC 3940/mm3, eosinophil 9%), elevated ESR, and an elevated serum total IgE level (5517 IU/ml). Ouchterlony's double diffusion test performed with the patient's serum in agarose showed strong bands toward Paragonimus westermani antigen, compared to Paragonimus miyazakii antigen. Immunoelectrophoresis with the patient's serum showed specific bands toward Paragonimus westermani antigen. This patient was finally diagnosed as having Paragonimiasis westermani infection, and he responded to praziquantel administration. The clinical course of this patient appears to be rare in cases of Paragonimiasis westermani infection. The clinical course of this case resembled some cases of Paragonimiasis miyazakii infection.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. 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.

  7. The soft tissue response to contaminated and cleaned titanium surfaces using CO2 laser, citric acid and hydrogen peroxide. An experimental study in the rat abdominal wall.

    PubMed

    Mouhyi, J; Sennerby, L; Van Reck, J

    2000-04-01

    The soft tissue response to clinically retrieved and decontaminated cover screws was evaluated in a rat model. The cover screws were cleaned by using citric acid, sterile water, hydrogen peroxide and CO2 laser alone or with a combination of these. In addition, decontaminated but not cleaned and unused cover screws were used as negative and positive controls, respectively. After cleaning the cover screws were implanted in the abdominal wall of the rat for 6 weeks. The thickness of the fibrous capsule and the number of macrophages within the capsule were measured by means of light microscopical morphometry. As compared to the negative control, CO2 laser on dry surface, CO2 laser + hydrogen peroxide and the positive control had statistically significant thinner fibrous capsules. As compared to the positive, only laser alone resulted in a similar tissue response. It is concluded that CO2 laser used alone or in combination with hydrogen peroxide may be used clinically for sufficient decontamination of titanium surfaces.

  8. Subcutaneous Splenosis of the Abdominal Wall: Report of a Case and Review of the Literature

    PubMed Central

    Papakonstantinou, Evangelia; Kalles, Vasileios; Papapanagiotou, Ioannis; Piperos, Theodoros; Karakaxas, Dimitrios; Bonatsos, Vasileios; Tsoumakas, Konstantinos; Orfanos, Filotheos; Mariolis-Sapsakos, Theodoros

    2013-01-01

    Splenosis is a common benign condition that occurs after splenic rupture via trauma or surgery. The mechanism behind splenic cell autotransplantation begins with the splenic rupture, either from trauma or surgical removal. Splenosis is usually found incidentally and, unless symptomatic, surgical therapy is not indicated. Subcutaneous splenosis is an extremely rare form of splenosis, mostly observed in abdominal surgical scars. We report a case of subcutaneous splenosis, as well as a comprehensive review of the literature. In our case, a 43-year-old woman who had splenectomy after traumatic splenic rupture at the age of 7 years old presented for plastic reconstruction of her postoperative scar. Upon surgery, two asymptomatic subcutaneous nodules were incidentally discovered. The presence of splenic tissue was confirmed by the histological study. The nodules were not excised, as the patient was not symptomatic. PMID:23401837

  9. 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.

  10. Experiments on fracture toughness of thick-wall cylinder for modes I, II, III

    SciTech Connect

    Saegusa, T.; Urabe, N.; Ito, C.; Shirai, K.; Kosaki, A.

    1999-07-01

    There have been few data on fracture toughness for Mode 2 and 3 as compared with those for Mode 1. Experimental data on fracture toughness of plates made of ductile cast iron (ASTM A874-89) and forged steel (ASME SA350 LF5 C1.1) were obtained at a temperature range from 77K to 293K for Mode 1, 2 and 3. The results showed: J{sub IC} < J{sub IIC} < J{sub IIIC}, and K{sub IC} < K{sub IIC} K{sub IIIC}. Integrity of a thick-wall cylinder with artificial flaw was demonstrated against brittle fracture at 233K for Mode 1, 2 and 3, which is one of the design requirements of containers shipping radioactive materials.

  11. Residual stress effect on fatigue crack growth in thick wall cylinders

    SciTech Connect

    Kiciak, A.; Glinka, G.; Burns, D.J.

    1995-11-01

    Recently derived weight functions for a single, semi-elliptical, longitudinal crack in a thick wall cylinder with the diameter ratio D{sub 0}/D{sub i} = 2, have been used to analyze fatigue crack propagation in autofrettaged and non-autofrettaged, pressurized cylinders. Two levels of autofrettage, 30 and 60%, have been considered. The influences of the level of autofrettage, surface crack closure, and different sets of parameters of crack closure, and different sets of parameters of crack propagation relation have been investigated. The development of cracks has been compared to the experimental results. The results of analyses confirm beneficial influence of autofrettage. It has been shown that the discrepancies between the observed and calculated crack developments cannot be ascribed to the influence of surface crack closure. The comparison of the experiments and predictions unveils the need for an additional series of experiments.

  12. Preferred propagation patterns of axial surface cracks in thick-walled cylinders

    SciTech Connect

    Perez, E.H.; Kendall, D.P.

    1996-12-01

    Semi-elliptical axial surface cracks, growing due to cyclic pressure loading in thick-walled cylinders undergo significant shape change during the propagation process. These growing cracks change their shapes such that they approach and follow preferred propagation patterns (PPPs). These PPPs depend on the diameter ratio of the cylinder and on the fatigue crack propagation constant, ``m`` in the Paris equation. The objective of this paper is to show the crack shape variation during fatigue crack growth using linear elastic fracture mechanics. It is shown that a crack whose initial shape does not agree with this preferred propagation pattern will grow such that its shape converges to the preferred pattern. The results of this study also show the effect of autofrettage on the PPPs and the final shape of the cracks at breakthrough.

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

    PubMed Central

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

    2014-01-01

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

  14. Helium ion microscopy based wall thickness and surface roughness analysis of polymer foams obtained from high internal phase emulsion.

    PubMed

    Rodenburg, C; Viswanathan, P; Jepson, M A E; Liu, X; Battaglia, G

    2014-04-01

    Due to their wide range of applications, porous polymers obtained from high internal phase emulsions have been widely studied using scanning electron microscopy. However, due to their lack of electrical conductivity, quantitative information of wall thicknesses and surface roughness, which are of particular interest to tissue engineering, has not been obtained. Here, Helium Ion Microscopy is used to examine uncoated polymer foams and some very strong but unexpected contrast is observed, the origin of which is established here. Based on this analysis, a method for the measurement of wall thickness variations and wall roughness measurements has been developed, based on the modeling of Helium ion transmission. The results presented here indicate that within the walls of the void structure there exist small features with height variations of ~30 nm and wall thickness variations from ~100 nm to larger 340 nm in regions surrounding interconnecting windows within the structure. The suggested imaging method is applicable to other porous carbon based structures with wall thicknesses in the range of 40-340 nm.

  15. Autosomal genome-wide linkage analysis to identify loci for gallbladder wall thickness in Mexican Americans.

    PubMed

    Samudrala, Narahari; Farook, Vidya S; Dodd, Gerald D; Puppala, Sobha; Schneider, Jennifer; Fowler, Sharon; Granato, Richard; Dyer, Thomas D; Arya, Rector; Almasy, Laura; Jenkinson, Christopher P; Diehl, Andrew K; Blangero, John; Duggirala, Ravindranath

    2008-02-01

    The significance of gallbladder wall thickness (GBWT) in regard to gallbladder disease (GBD) is not completely understood. Thickening of the gallbladder wall has been observed in patients with acute calculous and acalculous cholecystitis and chronic cholecystitis. However, various pathologic processes, such as gallbladder cancer and nonbiliary disorders such as liver cirrhosis and viral hepatitis, could also cause thickening of the gallbladder wall. To date, there is no report available on the genetic factors influencing GBWT. Therefore we sought to estimate the heritability (h2) of GBWT and to perform a genome-wide search to identify the susceptibility genes for GBWT, using data from the San Antonio Family Diabetes/Gallbladder Study (SAFDGS), a family study of Mexican Americans. GBWT was measured by ultrasound. After adjusting for the significant effects of age, sex, GBD (i.e., asymptomatic gallstones), metabolic syndrome, and duration of type 2 diabetes (T2DM), GBWT was found to be under significant and appreciable additive genetic influences (h2 +/- SE = 0.38 +/- 0.09, P < 0.0001). The strongest evidence for linkage occurred between markers D11S912 and D11S968 on chromosome 11q24-q25 (LOD = 2.7), where we have already shown suggestive evidence for linkage of GBD (LOD = 2.7) in a subset of our SAFDGS data. Potential evidence for linkage occurred at markers D1S1728 (1p31.1; LOD = 1.4) and D16S748 (16p13.1; LOD = 1.4), respectively. In conclusion, our study provides suggestive evidence for linkage of GBWT on chromosome 11q in Mexican Americans, and future tasks of mapping susceptibility gene(s) for GBD and its related traits, such as GBWT, in this chromosomal region can be fruitful. PMID:18505042

  16. 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.

  17. 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

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

    PubMed

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

    2012-03-01

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

  19. Early imaging of integration response to polypropylene mesh in abdominal wall by environmental scanning electron microscopy: comparison of two placement techniques and correlation with tensiometric studies.

    PubMed

    Ferrando, J M; Vidal, J; Armengol, M; Huguet, P; Gil, J; Manero, J M; Planell, J A; Segarra, A; Schwartz, S; Arbos, M A

    2001-07-01

    The repair of incisional hernias has taken advantage of the strength provided by prosthetic mesh grafts, but the best position for inserting the materials has not been conclusively established. Environmental scanning electron microscopy (ESEM) provides imaging of biologic samples with minimal manipulation. We used ESEM for early imaging of the integration response to polypropylene meshes placed in two anatomic positions in the abdominal wall and correlated results with tensiometric studies. Two macroporous polypropylene prostheses were implanted in a rat model--one on the abdominal aponeurotic layer and one on the peritoneal surface--without creating a wall defect. Studies were performed over implantation intervals of 7, 15, and 30 days in strips obtained from the polypropylene fiber-receptor repair tissue interface. Microscopic appearance, tensile strength, percent elongation, and stiffness were evaluated. Meshes implanted on the abdominal aponeurotic layer showed better early tissue incorporation (higher collagen deposition, capillary density, cell accumulation) and increased tensile strength, reflecting tighter anchorage to the abdominal wall. The percent elongation increased from day 7 to day 30 after implantation, mainly in the deep stratum. The ESEM images correlated well with biomechanical results, indicating the potential of this technique as a powerful, effective tool for use in wound-healing studies.

  20. 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.

  1. 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.

  2. Utilization of a global data grid repository in CAD assessment of carotid wall thickness

    NASA Astrophysics Data System (ADS)

    Gutierrez, Marco A.; Lee, Jasper; Zhou, Zheng; Pilon, Paulo E.; Lage, Silvia G.

    2007-03-01

    A CAD method of calculating wall thickness of carotid vessels addresses the time-consuming issue of using B-mode ultrasound as well as inter- and intra-observer variability in results. Upon selection of a region-of-interest and filtering of a series of ultrasound carotid images, the CAD is able to measure the geometry of the lumen and plaque surfaces using a least-square fitting of the active contours during systole and diastole. To evaluate the approach, ultrasound image sequences from 30 patients were submitted to the procedure. The images were stored on an international data grid repository that consists of three international sites: Image Processing and Informatics (IPI) Laboratory at University of Southern California, USA; InCor (Heart Institute) at Sao Paulo, Brazil, and Hong Kong Polytechnic University, Hong Kong. The three chosen sites are connected with high speed international networks including the Internet2, and the Brazilian National Research and Education Network (RNP2). The Data Grid was used to store, backup, and share the ultrasound images and analysis results, which provided a large-scale and a virtual data system. In order to study the variability between the automatic and manual definition of artery boundaries, the pooled mean and the standard deviation for the difference between measurements of lumen diameter were computed. The coefficient of variation and correlation were also calculated. For the studied population the difference between manual and automatic measurement of the lumen diameter (LD) and intima-media-thickness (IMT) were 0.12 +/-0.10 and 0.09+/- 0.06, respectively.

  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. 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

  5. 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.

  6. Dynamic Response of a Pulse-Heated, Thick-Walled, Hollow Sphere: Validation of Code Numerics

    SciTech Connect

    Canaan, R.E.

    2000-01-19

    Volumetric pulse heating of a thick-walled hollow sphere is numerically investigated. The primary objective is to validate a variety of LLNL 30 hydrocodes for modeling the dynamic behavior of fissile/fissionable metals subject to rapid ''fission-heating'' transients. The 30 codes tested include both DYNA3D and NIKE3D, as well as the ''ASCI'' code, ALE3D. The codes are compared ''head-to-head'' and are benchmarked against a 1D finite difference solution to the problem that is derived from basic principles. Three pulse-heating transients are examined with full-width-half-maximum pulse durations of 41{micro}s, 85{micro}s, and 140{micro}s, respectively. These three transients produce a significant range of dynamic responses in the thermo-elastic regime. We present results for dynamic radial displacements and stresses for each pulse, and also discuss which code features/options worked best for these types of calculations. In general, the code results are in excellent agreement for the simple system considered. Validation of code numerics in simple systems is a key first step toward future application of the codes in more complicated geometries (U).

  7. Effects of physical conditioning on the heart size and wall thickness of college women.

    PubMed

    Rubal, B J; Al-Muhailani, A R; Rosentswieg, J

    1987-10-01

    M-mode echocardiograms were obtained from 40 sedentary college women, 8 sprinters, 6 distance runners, 10 swimmers, 9 basketball players, 8 dancers, and 10 sedentary men (ages 19 to 31 yr). Treadmill stress tests were performed by all groups except the basketball players. The aerobic capacities of the athletes were 30 to 48% greater (P less than 0.05) than the sedentary subjects. The athletes exhibited trends toward higher than average left ventricular (LV) end-diastolic dimensions (7 to 25%), LV end-diastolic volumes (12 to 53%), stroke volume (13 to 52%), LV mass (11 to 42%), and left atrial dimensions (6 to 31%) when data were standardized for body surface area. A correlation (r = 0.323, P less than 0.05) was noted between LV mass index and maximal oxygen uptake when data were pooled. Ten sedentary women and ten age-matched sedentary men were endurance-conditioned by 10 wk of running. Both sexes increased maximal oxygen uptake approximately 20% (P less than 0.05) and exhibited similar changes in LV wall thickness, end-diastolic dimension, end-diastolic volume, and mass. These changes regressed within 10 wk after the termination of conditioning. This study suggests that women athletes exhibit cardiac morphologic features which resemble that reported for their male counterparts and that the cardiac response of sedentary men and women to modest levels of endurance conditioning is similar.

  8. 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.

  9. Wall thickness measurement using resonant phenomena of circumferential Lamb waves generated by plural transducer elements located evenly on girth

    NASA Astrophysics Data System (ADS)

    Nishino, Hideo; Iwata, Kodai; Ishikawa, Masashi

    2016-07-01

    We present a novel method of measuring the pipe wall thickness using the resonance of the circumferential (C-) Lamb wave generated by a piezoelectric ring-shaped sensor (PS). The PS is a special device for an axially propagating torsional wave; however, the C-Lamb waves are generated simultaneously as spurious signals owing to the structure of the PS. Particularly under resonant conditions, the C-Lamb waves are dominantly generated, distorting the axially propagating wave. In this method, these troublesome spurious signals are used effectively for the measurement of the wall thickness under the PS location that is a dead zone of the PS itself. The method can compensate for its drawback, namely, the dead zone problem, without using additional instruments. In this study, the mechanisms of the generation and resonance of the C-Lamb waves were first explained. Secondly, the principle of the wall thickness estimation utilizing the resonance of the C-Lamb waves was proposed. Finally, experimental verifications were carried out. The estimated wall thicknesses agreed very well (maximum 1.5% error) with those measured by a micrometer caliper under suitable resonant conditions.

  10. Optimum heating of thick-walled pressure components assuming a quasi-steady state of temperature distribution

    NASA Astrophysics Data System (ADS)

    Dzierwa, Piotr; Trojan, Marcin; Taler, Dawid; Kamińska, Katarzyna; Taler, Jan

    2016-08-01

    As a result of the development of wind farms, the gas — steam blocks, which shall quickly ensure energy supply in case the wind velocity is too low, are introduced to the energy system. To shorten the start-up time of the gas — steam and conventional blocks, the structure of the basic components of the blocks are changed, e.g. by reducing the diameter of the boiler, the thickness of its wall is also reduced. The attempts were also made to revise the currently binding TRD 301 regulations, replacing them by the EN 12952-3 European Standard, to reduce the allowable heating and cooling rates of thick walled boiler components. The basic assumption, on which the boiler regulations allowing to calculate the allowable temperature change rates of pressure components were based, was the quasi — steady state of the temperature field in the simple shaped component, such as a slab, cylindrical or spherical wall.

  11. 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.

  12. 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

  13. Surgery for Abdominal Wall Pain Caused by Cutaneous Nerve Entrapment in Children-A Single Institution Experience in the Last 5 Years

    PubMed Central

    Žganjer, Mirko; Bojić, Davor; Bumči, Igor

    2013-01-01

    Background Chronic abdominal pain (CAP) is a serious medical condition which needs to be approached with great attention. Chronic abdominal pain may be caused by entrapment of cutaneous branches of intercostal nerves (ACNES). Objectives The aim of this study is the surgery for abdominal wall pain which caused by cutaneous nerve entrapment in children during last 5 years. Materials and Methods In all children with ACNES, we tried conservative treatment with anesthetic and steroid injections. In children who were refractory to conservative treatment, we received surgical procedure like sectioning the entrapped nerve to obtain relief. Results In 12 pediatric patients with chronic abdominal pain, we diagnosed ACNES. Each presented with abdominal pain and a positive Carnett sign. Local nerve blocks using anesthetic and steroid injections are the treatment. In all patients, we tried with local nerve block. In 3 patients, pain improvement occurs in the few minutes, and they were without pain after 5 days. In other 4 patients required a reinjection for pain recurrence. In one patients pain was gone. The maximum reinjection was 3. In other 5 patients, we did operative treatment like sectioning the entrapped nerve. Conclusions Some children with CAP have ACNES. In all children with ACNES, we recommended local nerve blocks. If the local block in 3 times is not helping, neurectomy of the peripheral nerve is method of choice. PMID:23682329

  14. 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

  15. Reproducibility of Gadolinium Enhancement Patterns and Wall Thickness in Hypertrophic Cardiomyopathy

    PubMed Central

    Rodriguez-Granillo, Gaston A.; Deviggiano, Alejandro; Capunay, Carlos; Zan, Macarena C. De; Carrascosa, Patricia

    2016-01-01

    Background Reproducibility data of the extent and patterns of late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM) is limited. Objective To explore the reproducibility of regional wall thickness (WT), LGE extent, and LGE patterns in patients with HCM assessed with cardiac magnetic resonance (CMR). Methods The extent of LGE was assessed by the number of segments with LGE, and by the total LV mass with LGE (% LGE); and the pattern of LGE-CMR was defined for each segment. Results A total of 42 patients (672 segments) with HCM constituted the study population. The mean WT measurements showed a mean difference between observers of -0.62 ± 1.0 mm (6.1%), with limits of agreement of 1.36 mm; -2.60 mm and intraclass correlation coefficient (ICC) of 0.95 (95% CI 0.93-0.96). Maximum WT measurements showed a mean difference between observers of -0.19 ± 0.8 mm (0.9%), with limits of agreement of 1.32 mm; -1.70 mm, and an ICC of 0.95 (95% CI 0.91-0.98). The % LGE showed a mean difference between observers of -1.17 ± 1.2 % (21%), with limits of agreement of 1.16%; -3.49%, and an ICC of 0.94 (95% CI 0.88-0.97). The mean difference between observers regarding the number of segments with LGE was -0.40 ± 0.45 segments (11%), with limits of agreement of 0.50 segments; -1.31 segments, and an ICC of 0.97 (95% CI 0.94-0.99). Conclusions The number of segments with LGE might be more reproducible than the percent of the LV mass with LGE. PMID:27305110

  16. Westernization of lifestyle markedly increases carotid intima-media wall thickness (IMT) in Japanese people.

    PubMed

    Watanabe, Hiroshi; Yamane, Kiminori; Fujikawa, Rumi; Okubo, Masamichi; Egusa, Genshi; Kohno, Nobuoki

    2003-01-01

    To illustrate the impact of westernization of lifestyle on the development of pre-clinical atherosclerosis in Japanese people, we compared risk factors for atherosclerosis such as serum lipids, blood pressure, BMI, insulin resistance, and smoking habits between non-diabetic native Japanese and non-diabetic Japanese Americans. Two hundred and twenty two non-diabetic Japanese Americans living in Hawaii and 271 non-diabetic Japanese living in Hiroshima, Japan were studied. Carotid intima-media wall thickness (IMT) was measured in all subjects by one physician. For all measurements the same ultrasound instrumentation was used. Although no significant differences were seen in serum total cholesterol (TC), triglycerides, or LDL-cholesterol (LDL-C) levels between the two groups in the 1998 study, previous to 1998 these three parameters were significantly higher in Japanese Americans than native Japanese in our study which has spanned the past 20 years. IMT was significantly greater in Japanese Americans than native Japanese (1.20+/-0.03 mm vs. 0.98+/-0.03 mm, (mean+/-S.E.) respectively; P<0.0001). Moreover Japanese Americans reach an IMT of 1.1 mm at age 50, whereas the native Japanese reach this value at age 70. These observations indicate more rapid atherosclerosis progression in Japanese Americans. Based on our IMT measurements, the status and the estimated progression of atherosclerosis in Japanese Americans is increased. Since IMT is a validated endpoint for assessment of atherosclerotic disease risk, it can be concluded that Japanese Americans are at increased risk for cardiovascular disease.

  17. Pressure-induced wall thickness variations in multi-layered wall of a pollen tube and Fourier decomposition of growth oscillations.

    PubMed

    Pietruszka, Mariusz; Haduch-Sendecka, Aleksandra

    2015-04-01

    The augmented growth equation introduced by Ortega is solved for the apical portion of the pollen tube as an oscillating volume, which we approach in the framework of a two-fluid model in which the two fluids represent the constant pressure and the fluctuating features of the system. Based on routine Fourier analysis, we calculate the energy spectrum of the oscillating pollen tube, and discuss the resonant frequency problem of growth rate oscillations. We also outline a descriptive model for cell wall thickness fluctuations associated with small, yet regular variations (~ 0.01 MPa) observed in turgor pressure. We propose that pressure changes must lead to the sliding of wall layers, indirectly resulting in a wave of polarization of interlayer bonds. We conclude that pollen tube wall thickness may oscillate due to local variations in cell wall properties and relaxation processes. These oscillations become evident because of low amplitude/high frequency pressure fluctuations δP being superimposed on turgor pressure P. We also show that experimentally determined turgor pressure oscillates in a strict periodical manner. A solitary frequency f0 ≈ 0.066 Hz of these (~ 0.01 MPa in magnitude) oscillations for lily pollen tubes was established by the discrete Fourier transform and Lorentz fit.

  18. 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.

  19. Optical coherence tomography-based scanning system for shape determination, wall thickness mapping, and inner inspection of glass containers.

    PubMed

    Morel, Eneas Nicolás; Gutierrez, Marina Verónica; Miranda, Hernán Miguel; Sambrano, Edgardo Luis; Torga, Jorge Román

    2013-03-20

    In this work we present a method that enables simultaneous measurement of shape and wall parameters of glass containers. The system is based on the optical coherence tomography technique, employing the spectral domain configuration. The data were obtained by measuring the spatial coordinates of a sequence of points in a predefined region of a sample that includes points on the surface and in the interior of the material. Dimensional parameters, thickness mapping, and tomography studies of the interior of the sample walls can be obtained from these measurements. PMID:23518719

  20. Finite-element modelling of low-temperature autofrettage of thick-walled tubes of the austenitic stainless steel AISI 304 L: Part II. Thick-walled tube with cross-bore

    NASA Astrophysics Data System (ADS)

    Feng, H.; Donth, B.; Mughrabi, H.

    1998-01-01

    In part I, the autofrettage of a smooth thick-walled tube of the austenitic stainless steel AISI 304 L was studied by finite-element (FE) modelling. It was shown that low- temperature autofrettage is more efficient than autofrettage at room temperature, since it produces a larger beneficial compressive residual tangential (hoop) stress at the inner bore of the tube and hence permits a more significant enhancement of the fatigue resistance against pulsating internal pressure. The objective of the present study (part II) was to investigate the technically more relevant case of a thick-walled tube with a cross-bore made of the same steel. For this purpose, three-dimensional FE calculations were performed in order to characterize the influences of the autofrettage pressure and temperature on the stress and strain changes, in particular at the site of the cross-bore, also taking into account the effects of work hardening and reverse yielding. The results indicate that low-temperature autofrettage can also be applied advantageously in the case of thick-walled tubes with a cross-bore by virtue of the significantly larger residual compressive stresses, compared to room temperature autofrettage. From the quantitative FE calculations, the optimal combination of autofrettage temperature and pressure were concluded to lie in the range of 0965-0393/6/1/007/img1 to 0965-0393/6/1/007/img2, respectively. The calculated results were found to be in fair agreement with the measured values.

  1. 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

  2. Abdominal wall surgery

    MedlinePlus

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

  3. [Inconsistency between voltage of the electrocardiogram and the left ventricular wall thickness. diagnostic key in cardiac amyloidosis].

    PubMed

    Contreras, A; Beacon, E; Brenna, Eduardo J; Parisi, Gustavo R; Chamale, Roberto A; Gilardi, F; Bürguesser, M V; Salomone, O

    2013-01-01

    Restrictive cardiomyopathy is the least common form of cardiomyopathy, and the disease that most often cause it, is the system amyloidosis. We present a 62-year-old with a history of heart failure, which in its assessment highlights the discrepancy between the low voltage ventricular complexes in the electrocardiogram and the severity of left ventricular wall thickness on echocardiography. This discrepancy was the source of suspicion and subsequent confirmation of systemic amyloidosis with cardiac involvement.

  4. Stoichiometry, Length, and Wall Thickness Optimization of TiO2 Nanotube Array for Efficient Alcohol Sensing.

    PubMed

    Hazra, A; Bhowmik, B; Dutta, K; Chattopadhyay, P P; Bhattacharyya, P

    2015-05-13

    The present study concerns development of an efficient alcohol sensor by controlling the stoichiometry, length, and wall thickness of electrochemically grown TiO2 nanotube array for its use as the sensing layer. Judicious variation of H2O content (0, 2, 10 and 100% by volume) in the mixed electrolyte comprising ethylene glycol and NH4F resulted into the desired variation of stoichiometry. The sensor study was performed within the temperature range of 27 to 250 °C for detecting the alcohols in the concentration range of 10-1000 ppm. The nanotubes grown with the electrolyte containing 2 vol % H2O offered the maximum response magnitude. For this stoichiometry, variation of corresponding length (1.25-2.4 μm) and wall thickness (19.8-9 nm) of the nanotubes was achieved by varying the anodization time (4-16 h) and temperatures (42-87 °C), respectively. While the variation of length influenced the sensing parameters insignificantly, the best response magnitude was achieved for ∼13 nm wall thickness. The underlying sensing mechanism was correlated with the experimental findings on the basis of structural parameters of the nanotubes.

  5. 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.

  6. Riser Difference Evaluation from Ultrasonic Wall Thickness Inspection of Thirteen Double-Shell Tanks

    SciTech Connect

    Weier, Dennis R.; Pardini, Allan F.

    2010-03-15

    PNNL has performed an analysis of ultrasonic thickness measurements taken on Hanford's double-shell tanks (DSTs) approximately eight years apart. The analysis was performed to determine whether significant differences exist between ultrasonic thickness measurements made in two opposite risers in Hanford DSTs that have been examined twice.

  7. 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

  8. Evaluation of a canine small intestinal submucosal xenograft and polypropylene mesh as bioscaffolds in an abdominal full-thickness resection model of growing rats

    PubMed Central

    Lee, A-Jin; Lee, Sung-Ho; Chung, Wook-Hun; Kim, Dae-Hyun; Chung, Dai-Jung; Do, Sun Hee

    2013-01-01

    We evaluated the biological scaffold properties of canine small intestinal submucosa (SIS) compared to a those of polypropylene mesh in growing rats with full-thickness abdominal defects. SIS is used to repair musculoskeletal tissue while promoting cell migration and supporting tissue regeneration. Polypropylene mesh is a non-resorbable synthetic material that can endure mechanical tension. Canine SIS was obtained from donor German shepherds, and its porous collagen fiber structure was identified using scanning electron microscopy (SEM). A 2.50-cm2 section of canine SIS (SIS group) or mesh (mesh group) was implanted in Sprague-Dawley rats. At 1, 2, 4, 12, and 24 weeks after surgery, the implants were histopathologically examined and tensile load was tested. One month after surgery, CD68+ macrophage numbers in the SIS group were increased, but the number of CD8+ T cells in this group declined more rapidly than that in rats treated with the mesh. In the SIS group, few adhesions and well-developed autologous abdominal muscle infiltration into the SIS collagen fibers were observed. No significant differences in the tensile load test results were found between the SIS and mesh groups at 24 weeks. Canine SIS may therefore be a suitable replacement for artificial biological scaffolds in small animals. PMID:23628657

  9. Does mechanical massage of the abdominal wall after colectomy reduce postoperative pain and shorten the duration of ileus? Results of a randomized study.

    PubMed

    Le Blanc-Louvry, Isabelle; Costaglioli, Bruno; Boulon, Catherine; Leroi, Anne-Marie; Ducrotte, Philippe

    2002-01-01

    The aim of this study was to determine the effectiveness of mechanical abdominal massage on postoperative pain and ileus after colectomy. We hypothesized that parietal abdominal stimulation could counteract induced pain and postoperative ileus, through common spinal-sensitive pathways, with nociceptive visceral messages. After preoperative randomization, 25 patients (age 52 +/- 5 years) underwent active mechanical massage by intermittent negative pressure on the abdominal wall resulting in aspiration (Cellu M50 device, LPG, Valence, France), and 25 patients (age 60 +/- 6 years) did not receive active mechanical massage (placebo group). Massage sessions began the first day after colectomy and were performed daily until the seventh postoperative day. In the active-massage group, amplitude and frequency were used, which have been shown to be effective in reducing muscular pain, whereas in the placebo group, ineffective parameters were used. Visual analogue scale (VAS) pain scores, doses of analgesics (propacetamol), and delay between surgery and the time to first passage of flatus were assessed. Types and dosages of the anesthetic drugs and the duration of the surgical procedure did not differ between groups. From the second and third postoperative days, respectively, VAS pain scores (P < 0.001) and doses of analgesics (P < 0.05) were significantly lower in patients receiving active massage compared to the placebo group. Time to first passage of flatus was also significantly shorter in the active-massage group (1.8 +/- 0.3 days vs. 3.6 +/- 0.4 days, P < 0.01). No adverse effects were observed. These results suggest that mechanical massage of the abdominal wall may decrease postoperative pain and ileus after colectomy. PMID:11986017

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Space- and time-resolved resistive measurements of liquid metal wall thickness

    NASA Astrophysics Data System (ADS)

    Mirhoseini, S. M. H.; Volpe, F. A.

    2016-11-01

    In a fusion reactor internally coated with liquid metal, it will be important to diagnose the thickness of the liquid at various locations in the vessel, as a function of time, and possibly respond to counteract undesired bulging or depletion. The electrical conductance between electrodes immersed in the liquid metal can be used as a simple proxy for the local thickness. Here a matrix of electrodes is shown to provide spatially and temporally resolved measurements of liquid metal thickness in the absence of plasma. First a theory is developed for m × n electrodes, and then it is experimentally demonstrated for 3 × 1 electrodes, as the liquid stands still or is agitated by means of a shaker. The experiments were carried out with Galinstan, but are easily extended to lithium or other liquid metals.

  15. 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.

  16. Automatic airway wall segmentation and thickness measurement for long-range optical coherence tomography images

    NASA Astrophysics Data System (ADS)

    Qi, Li; Huang, Shenghai; Heidari, Andrew E.; Dai, Cuixia; Zhu, Jiang; Zhang, Xuping; Chen, Zhongping

    2016-03-01

    We present an automatic segmentation method for 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 were extracted using a graph-theory-based dynamic programming algorithm. The algorithm was tested with pig airway OCT images acquired with a custom built long range endoscopic OCT system. The performance of the algorithm was demonstrated by cross-validation between auto and manual segmentation experiments. Quantitative thicknesses changes in the mucosal layers are obtained automatically for smoke inhalation injury experiments.

  17. Safety Analysis Using Lebesgue Strain Measure of Thick-Walled Cylinder for Functionally Graded Material under Internal and External Pressure

    PubMed Central

    Aggarwal, A. K.; Sharma, Richa; Sharma, Sanjeev

    2013-01-01

    Safety analysis has been done for thick-walled circular cylinder under internal and external pressure using transition theory which is based on the concept of generalized principal Lebesgue strain measure. Results have been analyzed theoretically and discussed numerically. From the analysis, it can be concluded that circular cylinder made of functionally graded material is on the safer side of the design as compared to homogeneous cylinder with internal and external pressure, which leads to the idea of “stress saving” that minimizes the possibility of fracture of cylinder. PMID:24089605

  18. A temperature correlation for the radiation resistance of a thick-walled circular duct exhausting a hot gas

    NASA Technical Reports Server (NTRS)

    Mahan, J. R.; Cline, J. G.; Jones, J. D.

    1984-01-01

    It is often useful to know the radiation impedance of an unflanged but thick-walled circular duct exhausting a hot gas into relatively cold surroundings. The reactive component is shown to be insensitive to temperature, but the resistive component is shown to be temperature dependent. A temperature correlation is developed permitting prediction of the radiation resistance from a knowledge of the temperature difference between the ambient air and the gas flowing from the duct, and a physical basis for this correlation is presented.

  19. Safety analysis using Lebesgue strain measure of thick-walled cylinder for functionally graded material under internal and external pressure.

    PubMed

    Aggarwal, A K; Sharma, Richa; Sharma, Sanjeev

    2013-01-01

    Safety analysis has been done for thick-walled circular cylinder under internal and external pressure using transition theory which is based on the concept of generalized principal Lebesgue strain measure. Results have been analyzed theoretically and discussed numerically. From the analysis, it can be concluded that circular cylinder made of functionally graded material is on the safer side of the design as compared to homogeneous cylinder with internal and external pressure, which leads to the idea of "stress saving" that minimizes the possibility of fracture of cylinder.

  20. Safety analysis using Lebesgue strain measure of thick-walled cylinder for functionally graded material under internal and external pressure.

    PubMed

    Aggarwal, A K; Sharma, Richa; Sharma, Sanjeev

    2013-01-01

    Safety analysis has been done for thick-walled circular cylinder under internal and external pressure using transition theory which is based on the concept of generalized principal Lebesgue strain measure. Results have been analyzed theoretically and discussed numerically. From the analysis, it can be concluded that circular cylinder made of functionally graded material is on the safer side of the design as compared to homogeneous cylinder with internal and external pressure, which leads to the idea of "stress saving" that minimizes the possibility of fracture of cylinder. PMID:24089605

  1. The use of flow perfusion culture and subcutaneous implantation with fibroblast-seeded PLLA-collagen 3D scaffolds for abdominal wall repair.

    PubMed

    Pu, Fanrong; Rhodes, Nicholas P; Bayon, Yves; Chen, Rui; Brans, Gerben; Benne, Remco; Hunt, John A

    2010-05-01

    Highly cellularised 3D-tissue constructs designed to repair large, complex abdominal wall defects were prepared using poly (lactic acid) (PLLA)-collagen scaffolds in vitro using a flow perfusion bioreactor. The PLLA-collagen scaffolds had a unique structure consisting of a collagen sponge formed within the pores of a mechanically stable knitted mesh of PLLA. The effect of the flow perfusion bioreactor culturing conditions was investigated in vitro for 0, 7, 14 and 28 days on scaffolds seeded with dermal fibroblasts. The cultured constructs were subsequently studied subcutaneously (SC) in an in vivo animal model. The results of in vitro studies demonstrated that the perfusion system facilitated increased cell proliferation and homogenous distribution in the PLLA-collagen scaffolds compared to static conditions. A highly cellularised 3D-tissue construct was formed by 7 days incubation under perfusion conditions, with increased cellularity by the 28 day time point. The in vivo model demonstrated that implanting constructs with high cellularity resulted in exceptional cell stabilisation, with the survival of implanted cells and expression of the phenotypically-relevant extracellular matrix proteins collagen types I and III, studied by fluorescence in situ hybridisation (FISH) and immunohistochemistry. The implantation of this porous PPLA-collagen scaffold seeded with dermal fibroblasts following in vitro maturation using a flow perfusion bioreactor system suggests a significant advance over current state-of-the-art procedures for the reconstruction of large, complex abdominal wall tissue defects. PMID:20219244

  2. The hypertrophy of the lateral abdominal wall and quadratus lumborum is sport-specific: an MRI segmental study in professional tennis and soccer players.

    PubMed

    Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A; Dorado, Cecilia

    2013-03-01

    The aim was to determine the volume and degree of asymmetry of quadratus lumborum (QL), obliques, and transversus abdominis; the last two considered conjointly (OT), in tennis and soccer players. The volume of QL and OT was determined using magnetic resonance imaging in professional tennis and soccer players, and in non-active controls (n = 8, 14, and 6, respectively). In tennis players the hypertrophy of OT was limited to proximal segments (cephalic segments), while in soccer players it was similar along longitudinal axis. In tennis players the hypertrophy was asymmetric (18% greater volume in the non-dominant than in the dominant OT, p = 0.001), while in soccer players and controls both sides had similar volumes (p > 0.05). In controls, the non-dominant QL was 15% greater than that of the dominant (p = 0.049). Tennis and soccer players had similar volumes in both sides of QL. Tennis alters the dominant-to-non-dominant balance in the muscle volume of the lateral abdominal wall. In tennis the hypertrophy is limited to proximal segments and is greater in the non-dominant side. Soccer, however, is associated to a symmetric hypertrophy of the lateral abdominal wall. Tennis and soccer elicit an asymmetric hypertrophy of QL.

  3. 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

    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

  4. 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.

  5. 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.

  6. Collapse Pressure Analysis of Transversely Isotropic Thick-Walled Cylinder Using Lebesgue Strain Measure and Transition Theory

    PubMed Central

    Aggarwal, A. K.; Sharma, Richa; Sharma, Sanjeev

    2014-01-01

    The objective of this paper is to provide guidance for the design of the thick-walled cylinder made up of transversely isotropic material so that collapse of cylinder due to influence of internal and external pressure can be avoided. The concept of transition theory based on Lebesgue strain measure has been used to simplify the constitutive equations. Results have been analyzed theoretically and discussed numerically. From this analysis, it has been concluded that, under the influence of internal and external pressure, circular cylinder made up of transversely isotropic material (beryl) is on the safer side of the design as compared to the cylinders made up of isotropic material (steel). This is because of the reason that percentage increase in effective pressure required for initial yielding to become fully plastic is high for beryl as compared to steel which leads to the idea of “stress saving” that reduces the possibility of collapse of thick-walled cylinder due to internal and external pressure. PMID:24523632

  7. FRAM isotopic analysis of uranium in thick-walled containers using high energy gamma rays and planar HPGe detectors.

    SciTech Connect

    Sampson, Thomas E.; Hypes, P. A.; Vo, Duc T.

    2002-01-01

    We describe the use of the Los Alamos FRAM isotopic analysis software to make the first reported measurements on thick-walled UF{sub 6} cylinders using small planar HPGe detectors of the type in common use at the IAEA. Heretofore, planar detector isotopic analysis measurements on uranium have used the 100-keV region and can be defeated by 10 mm of steel absorber. The analysis of planar detector measurements through 13-16 mm of steel shows that FRAM can successfully carry out these measurements and analysis in the 120-1024 keV energy range, a range previously thought to be the sole province of more efficient coaxial detectors. This paper describes the measurement conditions and results and also compares the results to other FRAM measurements with coaxial HPGe detectors. The technique of gamma-ray isotopic analysis of arbitrary samples is desirable for measuring the isotopic composition of uranium in UF{sub 6} cylinders because it does not require calibration with standards or knowledge of the cylinder wall thickness. The International Atomic Energy Agency (IAEA) uses the MGAU (Multi Group Analysis Uranium) uranium isotopic analysis software with planar high purity germanium (HPGe) detectors to measure the isotopic composition of uranium. Measurements on UF{sub 6} cylinders with 13-16-mm thick steel walls are usually unsuccessful because of the strong absorption of the 89-100 keV gamma rays and x-rays that MGAU requires for the measurement. This paper describes the use of the Los Alamos FRAM isotopic analysis software to make these measurements on UF{sub 6} cylinders. Uranium measurements with FRAM typically cover the energy range from 120-1001 keV and can easily be made through the walls of UF{sub 6} cylinders. While these measurements are usually performed with efficient coaxial HPGe detectors, this paper reports the first successful measurements using small planar HPGe detectors of the type in common use at the IAEA.

  8. [Surgical treatment of the defects of the lumbar-lateral region of the abdominal wall in elderly and senile patients].

    PubMed

    Vorovs'kyĭ, O O

    2012-12-01

    The results of surgical treatment of 44 patients with defects in the lumbar-lateral abdomen. Age of patients ranged from 60 to 78 years. Causes defects in 32 (72.7%) patients were hernia after surgical interventions on the urinary system using lumbotomic accesses; in 4 (9.1%)--hernias, in 2 (4.5%)--eventration after applying troakar lateral openings during laparoscopic surgery; in 2 (4.5%)--hernias, in 2 (4.5%)--eventration, and in 2 (4.5%)--evisceration through aperture after removing drains for drainage of the abdominal cavity. To prevent the development of the proposed method of drainage of the abdominal cavity during laparoscopic operations (patent for useful model No 51170 from 12.07.10). Autotransplantation own tissues justified by the size of the defect W1. If there is a defect larger aloplastyc shown by the method of sub lay in the proposed original method.

  9. 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

  10. Characteristics of colorectal cancer diagnosed with screening abdominal ultrasonography

    PubMed Central

    TOMIZAWA, MINORU; SHINOZAKI, FUMINOBU; HASEGAWA, RUMIKO; FUGO, KAZUNORI; SHIRAI, YOSHINORI; MOTOYOSHI, YASUFUMI; SUGIYAMA, TAKAO; YAMAMOTO, SHIGENORI; KISHIMOTO, TAKASHI; ISHIGE, NAOKI

    2016-01-01

    Patient records were retrospectively analyzed to elucidate the characteristics of patients with colorectal cancer (CRC) diagnosed with screening abdominal ultrasound (US). Patients diagnosed with CRC using abdominal US [localized irregular wall thickening (W) or a hypoechoic mass with a hyperechoic mass (M)] were enrolled. The patients were subjected to colonoscopy and treated surgically between March, 2010 and January, 2015. A total of 5 men (aged 74.0±0.8 years) and 10 women (aged 73.0±12.0 years) were analyzed. Stratification was analyzed with abdominal US. The threshold value of wall thickness to diagnose CRC was investigated with receiver operating characteristic (ROC) curve analysis. The average wall thickness was 2.8±0.4 mm in the surrounding normal tissue and 12.7±5.2 mm in CRC (one-way analysis of variance, P<0.0001). The wall was significantly thicker in CRC compared with the normal colonic wall. The calculated threshold value was 4.3 mm for the diagnosis of CRC. Stratification was preserved in W, while it was lost in M (Chi-squared test, P=0.0196). The hemoglobin concentration was lower, while the C-reactive protein, carcinoembryonic antigen and carbohydrate antigen 19-9 levels were elevated above normal values. The threshold value was 4.3 mm for the diagnosis of CRC with abdominal US. PMID:27330768

  11. Abdominal tap

    MedlinePlus

    Peritoneal tap; Paracentesis; Ascites - abdominal tap; Cirrhosis - abdominal tap; Malignant ascites - abdominal tap ... abdominal cavity ( most often cancer of the ovaries ) Cirrhosis of the liver Damaged bowel Heart disease Infection ...

  12. Analysis of abdominal wounds made by surgical trocars using functional luminal imaging probe (FLIP) technology.

    PubMed

    McMahon, Barry P; O'Donovan, Deidre; Liao, Donghua; Zhao, Jingbo; Schiretz, Rich; Heninrich, Russell; Gregersen, Hans

    2008-09-01

    The aim was to use a novel functional luminal imaging probe for evaluation of wound defects and tissue damage resulting from the use of trocars. Following general anesthesia of 4 adult pigs, 6 different trocars were randomly inserted at preselected locations in the porcine abdominal wall. The functional luminal imaging probe was used to profile the trocar holes during bag distension from 8 axial cross-sectional area measurements. The cross-sectional areas and pressure in the bag were recorded and exported to Matlab for analysis and data display. Geometric profiles were generated, and the minimum cross-sectional area and hole length (abdominal wall thickness) were used as endpoints. Successful distensions were made in all cases. The slope of the contours increased away from the narrowest point of the hole. The slope increased more rapidly toward the inner abdominal wall than toward the outer wall. The slope of the linear trend lines for the cross-sectional area-pressure relation represents the compliance at the narrowest point in the wall. The hole length (abdominal wall thickness) could be obtained at different cross-sectional area cutoff points. A cutoff point of 300 mm(2) gave good results when compared to the length of the hole measured after the tissue was excised. This technique represents a new and straightforward way to evaluate the effects of trocars on the abdominal wall. It may also prove useful in comparing techniques and technology from different manufacturers. PMID:18757380

  13. Strength-toughness requirements for thick-walled high pressure vessels

    NASA Astrophysics Data System (ADS)

    Kapp, Joseph A.

    1992-05-01

    The strength and toughness requirements of materials used in high pressure vessels has been the subject of some discussion in the meetings of the Materials Task Group of the Special Working Group - High Pressure Vessels. A fracture mechanics analysis has been performed to theoretically establish the required toughness for a high pressure vessel. The analysis is based on the validity requirement for plane-strain fracture of fracture toughness test specimens. This means that at fracture, the crack length, uncracked ligament, and vessel length must each be greater than fifty times the crack tip plastic zone since for brittle fracture to occur. For high pressure piping applications, the limiting physical dimension is the uncracked ligament, since it can be assumed that the other dimensions are always greater than fifty times the crack tip plastic zone. To perform the fracture mechanics analysis, several parameters must be known, including vessel dimensions, material strength, degree of autofrettage, and design pressure. Remarkably, the results of the analysis show that the effects of radius ratio, pressure, and degree of autofrettage can be ignored when establishing strength and toughness requirements for design code purposes. The only parameters that enter into the calculation are yield strength, toughness and vessel thickness. The final results can easily be represented as a graph of yield strength against toughness on which several curves, one for each vessel thickness, are plotted.

  14. 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.

  15. Application of Internal Fusible Chills in Thick-Walled Castings Made of EN-GJS with an Optimized Microstructure

    NASA Astrophysics Data System (ADS)

    Krupa, Wojciech; Tonn, Babette

    2011-01-01

    The degeneration of graphite in thick-walled components made of ductile iron due to slower solidification affects the mechanical properties and is unacceptable for all safety-relevant components. The inoculation of the melt no longer leads to a fine microstructure. After exceeding the critical solidification time, degenerated shapes of graphite are to be expected. The external cooling with a chill-mould does not eliminate graphite degeneration in the thermal centres. The positive effect of these chills is also limited by the wall thickness. The aim of this study was to increase the heat dissipation of the melt by positioning the internal fusible chills in the thermal centre of the mould cavity. This should lead to accelerated solidification. The plate-shaped chills were placed in the middle of rectangular samples. The solidification processes were first simulated with Magmasoft in order to optimize the size and shape of the fusible chills and to thus guarantee a complete dissolving of the chills. A reduction in the solidification time of approximately 15% was achieved. In the experiments thick-walled samples were cast with and without internal fusible chills and compared. Areas with degenerated graphite, including chunky graphite, were found in the centres of the cast samples without internal cooling. Placing fusible chills in castings increased the number of graphite spheroids in the microstructure and exhibited no graphite degeneration. A homogenous microstructure was developed—no residues of the chills were found. Differences in microstructure and mechanical properties between the edges and centres of the casting could be nullified. The optimized graphite morphology of the casting with internal cooling led to an increase in tensile strength in the thermal centre of about 30 MPa (8%). This process was successfully implemented in an industrial environment. Blocks out of EN-GJS-400 for use in hydraulic engineering with a total weight of eight tonnes were cast in

  16. 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.

  17. The use of thick-walled hollow cylinder creep tests for evaluating flow criteria for rock salt

    SciTech Connect

    Morgan, H.S.; Wawersik, W.R.

    1990-01-01

    Finite element simulations of two laboratory creep tests on thick-walled hollow cylinders of rock salt are evaluated to determine if such bench-scale experiments can be used to establish applicability of either von Mises or Tresca stress measures and associated flow conditions. In the tests, the cylinders were loaded axially and pressurized both internally and externally to produce stress fields similar to those found around underground excavations in rock salt. Several different loading stages were used in each test. The simulations show that for each of two creep models studied, quite different deformations of the cylinders are predicted with the Mises and Tresca flow criteria, especially if friction between the cylinders and axial loading platens is ignored. When friction is included in the simulations, the differences in deformation are changed but are sill clearly distinguishable. 10 refs., 10 figs.

  18. Fracture behavior of shallow cracks in full-thickness clad beams from an RPV wall section

    SciTech Connect

    Keeney, J.A.; Bass, B.R.; McAfee, W.J.

    1995-04-01

    A testing program is described that utilizes full-thickness clad beam specimens to quantify fracture toughness for shallow cracks in weld material for which metallurgical conditions are prototypic of those found in reactor pressure vessels (RPVs). The beam specimens are fabricated from an RPV shell segment that includes weld, plate and clad material. Metallurgical factors potentially influencing fracture toughness for shallow cracks in the beam specimens include material gradients and material inhomogeneities in welded regions. The shallow-crack clad beam specimens showed a significant loss of constraint similar to that of other shallow-crack single-edge notch bend (SENB) specimens. The stress-based Dodds-Anderson scaling model appears to be effective in adjusting the test data to account for in-plane loss of constraint for uniaxially tested beams, but cannot predict the observed effects of out-of-plane biaxial loading on shallow-crack fracture toughness. A strain-based dual-parameter fracture toughness correlation (based on plastic zone width) performed acceptably when applied to the uniaxial and biaxial shallow-crack fracture toughness data.

  19. Application of the new Section XI, A-3000 method for stress intensity factor calculation to thick-walled pressure vessels

    SciTech Connect

    Kendall, D.P.

    1996-12-01

    The ASME Boiler and Pressure Vessel Code, Section XI, Appendix A, Article A-3000 has been recently revised to include a more accurate method for calculating stress intensity factors. It is based on fitting the distribution of the stress normal to the plane of the crack in the uncracked body, over the depth of the crack, with a cubic equation. The coefficients of this equation are used with correction factors given in the code to calculate the stress intensity factors at the deepest point of the crack and near the free surface. Correction factors are given for a range of values of relative crack depth and crack shape. In a pressurized thick-walled cylinder the stresses of interest are the tangential stresses due to internal pressure as given by the Lame Equations, plus the effect of the pressure in the crack. This paper shows that the Lame stresses, as a function of distance from the inner surface, can be accurately fitted with a simple set of cubic equations over the full wall thickness for a wide range of diameter ratios. The coefficients of these equations, combined with the correction factors, are used to calculate stress intensity factors for a range of diameter ratios and at both the deepest point of the crack and near the free surface. The results are compared with stress intensity factors calculated using the linearized stress method proposed by Kendall and Perez. The effect of the plastic zone correction given in the new method is reported. The stress intensity factors due to autofrettage residual stresses calculated by the new method are also reported.

  20. 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

  1. 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.

  2. Photovoltaic response of carbon nanotube-silicon heterojunctions: effect of nanotube film thickness and number of walls.

    PubMed

    Castrucci, P; Del Gobbo, S; Camilli, L; Scarselli, M; Casciardi, S; Tombolini, F; Convertino, A; Fortunato, G; De Crescenzi, M

    2011-10-01

    We report on the multiwall carbon nanotube application as energy conversion material to fabricate thin film solar cells, with nanotubes acting as photogeneration sites as well as charge separators, collectors and carrier transporters. The device consists of a semitransparent thin film of nanotubes coating a n-type crystalline silicon substrate. Under illumination electron-hole (e-h) pairs, generated in the nanotubes and in the silicon substrate underneath, are split and charges are transported through the nanotubes (electrons) and the n-Si (holes). We found that a suitable thickness of the nanotube thin film, high density of Schottky junctions between nanotubes and n-Si and lowest number of nanotube walls are all fundamental parameters to improve the device incident photon to electron conversion efficiency. Multiwall carbon nanotubes have been synthesized by chemical vapour deposition in an ultra high vacuum chamber by evaporating a given amount of iron at room temperature and then exposing the substrate kept at 800 degrees C at acetylene gas. The amount of deposited iron is found to directly affect the nanotube size distribution (inner and outer diameter) and therefore the number of walls of the nanotubes.

  3. A Cyclooxygenase-2 Inhibitor Reduces Vascular Wall Thickness and Ameliorates Cognitive Impairment in a Cerebral Small Vessel Diseases Rat Model.

    PubMed

    Tang, Jie; Xiao, Weizhong; Li, Qinghua; Deng, Qiuqiong; Chu, Xinquan; Chen, Yang; Pan, Danhong; Fu, Jianhui

    2015-01-01

    Cerebral small vessel disease (CSVD) is a group of diseases that originate from changes in cerebral small vessels and that cause many conditions, such as cognitive impairment. However, there is no effective therapy for these diseases. Recent studies have suggested that inflammation is associated with this disease. Cyclooxygenase-2 (cox-2) is an inflammatory mediator; however, whether a cox-2 inhibitor could protect against the CSVD progression remains unknown. In the present study, stroke-prone spontaneously hypertensive rats (SHRsp) were used as a model of CSVD, and Sprague Dawley (SD) rats served as the control. SHRsp were treated with the cox-2 inhibitor celecoxib or vehicle. The Morris water maze test was performed, and vascular morphometry and the expression of collagen I and fibronectin were examined in cerebral small vessels and cerebral tissue. The results revealed that thickened small veesel walls, increased expression of collagen I and fibronectin and impaired cognitive function in SHRsp compared with SD rats. Additionally, celecoxib significantly down-regulated the expression of collagen I and fibronectin, attenuated the increase in vascular wall thickness and ameliorates the cognitive impairment. Our study indicated that this cox-2 inhibitor may serve as a promising candidate for the pharmacological intervention of CSVD. PMID:26159203

  4. Effect of material properties on the strain to failure of thick-walled cylinders subjected to internal pressure

    SciTech Connect

    Roach, D.P.; Priddy, T.G. )

    1994-05-01

    The determination of the fully plastic response and pressure limit of a pressure vessel is of considerable importance in design, especially in autofrettage considerations. This paper presents the results of an experimental study which measured the maximum internal pressure which can be applied to thick-walled cylindrical vessels. Both aluminum and steel, with material properties ranging from ductile to brittle, were tested at stress levels through plastic and strain hardening ranges to fracture. From these tests, the pressure-expansion and through-thickness yielding characteristics were determined for these specimens. It is shown that a strain-to-failure criterion, based on the triaxiality of stress in the critical region, can be used to predict the complete pressure versus strain relations and maximum pressure for these cylinders. A simple tension-true stress-strain relation of the material is employed to analytically predict the response of the cylinder into the plastic regime. Finally, simplified theoretical and empirical formulas for bursting pressures are checked against the experimental results.

  5. 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

  6. Importance of head diameter, clearance, and cup wall thickness in elastohydrodynamic lubrication analysis of metal-on-metal hip resurfacing prostheses.

    PubMed

    Liu, Feng; Jin, Zhongmin; Roberts, P; Grigoris, P

    2006-08-01

    The main design features of metal-on-metal (MOM) hip resurfacing prostheses in promoting elastohydrodynamic lubrication were investigated in the present study, including the femoral head diameter, the clearance, and the cup wall thickness. Simplified conceptual models were developed, based on equivalent uniform wall thicknesses for both the cup and the head as well as the support materials representing bone and cement, and subsequently used for elastohydrodynamic lubrication analysis. Both typical first- and second-generation MOM hip resurfacing prostheses with different clearances and cup wall thicknesses were considered with a fixed large bearing diameter of 50 mm, as well as a 28 mm diameter MOM total hip replacement bearing for the purpose of comparison. The importance of the head diameter and the clearance in promoting elastohydrodynamic lubrication was confirmed. Furthermore, it was also predicted that a relatively thin acetabular cup in the more recently introduced second-generation MOM hip resurfacing prostheses would be capable of improving elastohydrodynamic lubrication even further.

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

    PubMed

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

    2012-09-01

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

  8. Numerical study of the coupling of two identification methods - thermal and electromagnetic - for the reconstruction of inclusions in thick walls

    NASA Astrophysics Data System (ADS)

    Le Touz, Nicolas; Dumoulin, Jean; Soldovieri, Francesco

    2016-04-01

    In this numerical study we present an approach allowing introducing a priori information in an identification method of internal thermal properties field for a thick wall using infrared thermography measurements. This method is based on a coupling with an electromagnetic reconstructing method which data are obtained from measurements of Ground Penetrating Radar (GPR) ([1], [2]). This new method aims at improving the accuracy of reconstructions performed by using only the thermal reconstruction method under quasi-periodic natural solicitation ([3], [4]). Indeed, these thermal reconstructions, without a priori information, have the disadvantage of being performed on the entire studied wall. Through the intake of information from GPR, it becomes possible to focus on the internal zones that may contain defects. These areas are obtained by defining subdomains around remarkable points identified with the GPR reconstruction and considered as belonging to a discontinuity. For thermal reconstruction without providing a priori information, we need to minimize a functional equal to a quadratic residue issued from the difference between the measurements and the results of the direct model. By defining search fields around these potential defects, and thus by forcing the thermal parameters further thereof, we provide information to the data to reconstruct. The minimization of the functional is then modified through the contribution of these constraints. We do not seek only to minimize a residue, but to minimize the overall residue and constraints, what changes the direction followed by the optimization algorithm in the space of thermal parameters to reconstruct. Providing a priori information may then allow to obtain reconstruction with higher residues but whose thermal parameters are better estimated, whether for locating potential defects or for the reconstructed values of these parameters. In particular, it is the case for air defects or more generally for defects having a

  9. Finite-element modelling of low-temperature autofrettage of thick-walled tubes of the austenitic stainless steel AISI 304 L: Part I. Smooth thick-walled tubes

    NASA Astrophysics Data System (ADS)

    Feng, H.; Mughrabi, H.; Donth, B.

    1998-01-01

    The stresses and strains introduced by low-temperature autofrettage of smooth thick-walled tubes made of the austenitic stainless steel AISI 304 L were modelled by the finite-element (FE) method. The objective was to show that low-temperature autofrettage is much more efficient than autofrettage at room temperature in enhancing the fatigue resistance by introducing a higher beneficial tangential (hoop) residual compressive stress at the inner part of the tube. Attention was paid to the influences of the autofrettage temperature and pressure, the work hardening and the reverse yielding on the residual stress components and on the total strain components of the tube. The FE calculations confirmed that more beneficial residual stress patterns can be attained by autofrettage at low rather than at room temperature. From the quantitative calculations, the optimal autofrettage temperature and pressure of the tube were concluded to be about 0965-0393/6/1/006/img1 and 4000 bar, respectively. The results of the calculations were shown to be in good agreement with recently measured data.

  10. 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

  11. 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.

  12. Experimental and numerical study of fatigue crack propagation in a thick-walled cylinder under cyclic hoop stress

    NASA Astrophysics Data System (ADS)

    Salam, I.; Malik, M. A.; Abid, M.; Farooque, M.

    2014-06-01

    In present work, after finding the anisotropy resulting in dissimilar properties in different orientations of a thick-walled cylinder, experimental and numerical study was performed to reveal the fatigue crack growth behavior of the cylinder under cyclic hoop stress. Fatigue crack growth experiments were conducted on middle tension M(T) samples prepared in an orientation to simulate the hoop stress on the cylinder. The tests were conducted under constant amplitude loading at R ratio 0.1. The fatigue crack growth data was compiled and applied to simulate and predict the crack growth process using two dimensional parametric finite element technique. The fatigue crack propagation was simulated, based on linear elastic fracture mechanics and stress intensity factor determination. Both the experimental and numerical results of crack growth data, at stress levels of 10 to 40 per cent of the yield stress of the material, were found in close agreement. The disparity observed was concluded in the range of statistical scatter in the experimental data. The crack growth rate and the fatigue life of the samples obtained from the experiments and the simulation were also in good agreement at all the stress levels analyzed.

  13. Effect of reducing field of view on multi-detector quantitative computed tomography parameters of airway wall thickness in asthma

    PubMed Central

    Sheshadri, Ajay; Rodriguez, Alfonso; Chen, Ryan; Kozlowski, James; Burgdorf, Dana; Koch, Tammy; Tarsi, Jaime; Schutz, Rebecca; Wilson, Brad; Schechtman, Kenneth; Leader, Joseph K.; Hoffman, Eric A.; Castro, Mario; Fain, Sean B.; Gierada, David S.

    2015-01-01

    Objective We reduced the CT-reconstructed field of view (FOV), increasing pixel density across airway structures and reducing partial volume effects, to determine whether this would improve accuracy of airway wall thickness quantification. Methods We performed CT imaging on a lung phantom and 29 subjects. Images were reconstructed at 30, 15, and 10 cm FOV using a medium-smooth kernel. Cross-sectional airway dimensions were compared at each FOV with repeated-measures analysis of variance. Results Phantom measurements were more accurate when FOV decreased from 30 to 15 cm (p<0.05). Decreasing FOV further to 10 cm did not significantly improve accuracy. Human airway measurements similarly decreased by decreasing FOV (p<0.001). Percent changes in all measurements when reducing FOV from 30 to 15 cm were less than 3%. Conclusions Airway measurements at 30 cm FOV are near the limits of CT resolution using a medium-smooth kernel. Reducing reconstructed FOV would minimally increase sensitivity to detect differences in airway dimensions. PMID:25938213

  14. Influence of thick-walled cylinders length on the residual stresses generated during the single-cycle mandrelling

    NASA Astrophysics Data System (ADS)

    Skvortsov, V. F.; Boznak, A. O.; Kim, A. B.; Arlyapov, A. Yu

    2015-09-01

    The paper presents methodology and results of experimental study by Sachs method the effect of length of mandrelled thick-walled cylinders made of steel grade 50 (0.5% C) with 5 mm diameter hole, outer diameter of 15 and 25 mm on residual stresses. Based on the review of studies, it was noted that this effect may be both due to uneven process of mandrelling along the cylinder length and due to zero axial residual stresses on its faces. It was found that the length of cylinders has the strongest influence on axial residual stresses. With allowances between 0.9 and 7.1% and length reduction from 40 to 10 mm, the largest absolute value of axial residual stresses decreases from 210 to 50 MPa. It was noted that when the outer diameter of cylinders is 15 mm their length significantly influence on both hoop and radial residual stresses. With the above-mentioned decrease in cylinders length, absolute values of hoop and radial residual stresses in the region adjacent to the hole, depending on the mandrelling allowance, increase (from -135 to -205 MPa and from -45 to 55 MPa respectively, when allowance is 7.1%), decrease (from -315 to -235 MPa and from -135 to -95 MPa respectively, when allowance is 0.9%) and remain almost unchanged (when allowance is 3.4%). Impact of length on these stresses is weak when the outer diameter of cylinders is 25 mm.

  15. 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.

  16. 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

  17. Associations of coronary heart disease with common carotid artery near and far wall intima-media thickness (IMT): the Multi-Ethnic Study of Atherosclerosis

    PubMed Central

    Polak, Joseph F.; Szklo, Moyses; O’Leary, Daniel H

    2015-01-01

    Background Intima-media thickness (IMT) measured on ultrasound images of the common carotid artery (CCA) is associated with cardiovascular risk factors and events. Based on the physics of ultrasound, CCA far wall IMT measurements are favored over near wall measurements but this theoretical advantage is not well studied. Methods We studied 6606 members of the Multi-Ethnic Study of Atherosclerosis (MESA), a longitudinal cohort study (mean age 62.1 years; 52.7% female) who had near wall and far wall CCA IMT measurements. Multivariable linear regression models were used to estimate model goodness-of-fit of Framingham risk factors (FRF) with near wall IMT, far wall IMT, and combined mean IMT. Multivariable Cox proportional hazards models were used to estimate hazard ratios for incident coronary heart disease (CHD) events for each IMT variable. Change in Harrell’s C-statistic was used to compare the incremental value of each IMT variable when added to FRF. Results Mean IMT had the strongest association with risk factors (R2 = 0.31), followed by the near wall (R2 = 0.26) and far wall IMT (R2 = 0.22). Far wall IMT improved the prediction of coronary artery disease events over the FRF (change in C-statistic of 0.012; 95% confidence intervals: 0.006, 0.017; p < 0.001) as did mean IMT (p = 0.004) but near wall IMT did not. Conclusions Far wall CCA IMT showed the strongest association with incident CHD whereas mean IMT had the strongest associations with risk factors. This difference might affect the selection of appropriate IMT variables in different studies. PMID:25944425

  18. 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.

  19. ENDOSCOPIC FULL THICKNESS BIOPSY OF THE GASTRIC WALL WITH DEFECT CLOSURE USING AN ENDOSCOPIC SUTURING DEVICE: SURVIVAL PORCINE STUDY

    PubMed Central

    Rajan, E; Gostout, CJ; Bonin, E Aimore; Moran, EA; Locke, GR; Szarka, LA; Talley, NJ; Deters, JL; Miller, CA; Knipschield, MA; Lurken, MS; Stoltz, GJ; Bernard, CE; Grover, M; Farrugia, G

    2013-01-01

    Background The pathogenesis of several common gastric motility diseases and functional gastrointestinal disorders remains essentially unexplained. Gastric wall biopsies that include the muscularis propria to evaluate the enteric nervous system, interstitial cells of Cajal and immune cells can provide important insights to our understanding of the etiology of these disorders. Objectives To determine 1. Technical feasibility, reproducibility and safety of performing a full thickness gastric biopsy (FTGB) using a submucosal endoscopy with mucosal flap (SEMF) technique; 2. Technical feasibility, reproducibility and safety of tissue closure using an endoscopic suturing device; 3. Ability to identify myenteric ganglia in resected specimens; 4. Long-term safety. Design Single center, pre-clinical survival study. Setting Animal research laboratory – Developmental Endoscopy Unit. Subjects Twelve domestic pigs. Interventions Animals underwent a SEMF procedure with gastric muscularis propria resection. The resultant offset mucosal entry site was closed using an endoscopic suturing device. Animals were survived for 2 weeks. Main Outcome Measurements 1. Technical feasibility, reproducibility and safety of the procedure 2. Clinical course of the animals 3. Histological and immunochemical evaluation of the resected specimen to determine if myenteric ganglia were present in the sample. Results FTGB was achieved using the SEMF technique in all 12 animals. The offset mucosal entry site was successfully closed using the suturing device in all animals. Mean resected tissue size was 11 mm. Mean total procedure time was 61 mins with 2–4 interrupted sutures placed per animal. Histology showed musclaris propria and serosa confirming full thickness resections in all animals. Myenteric ganglia were visualized in 11/12 animals. The clinical course was uneventful. Repeat endoscopy and necropsy at 2 weeks showed absence of ulceration at either the mucosal entry sites or overlying the more

  20. 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

  1. 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

  2. Anterior vaginal wall repair

    MedlinePlus

    ... your health care provider may have you learn pelvic floor muscle exercises ( Kegel exercises ), use estrogen cream in ... GM. Anatomic defects of the abdominal wall and pelvic floor: abdominal and inguinal hernias, cystocele, urethrocele, enterocele, rectocele, ...

  3. High vancomycin MICs within the susceptible range in Staphylococcus aureus bacteraemia isolates are associated with increased cell wall thickness and reduced intracellular killing by human phagocytes.

    PubMed

    Falcón, Rocío; Martínez, Alba; Albert, Eliseo; Madrid, Silvia; Oltra, Rosa; Giménez, Estela; Soriano, Mario; Vinuesa, Víctor; Gozalbo, Daniel; Gil, María Luisa; Navarro, David

    2016-05-01

    Vancomycin minimum inhibitory concentrations (MICs) at the upper end of the susceptible range for Staphylococcus aureus have been associated with poor clinical outcomes of bloodstream infections. We tested the hypothesis that high vancomycin MICs in S. aureus bacteraemia isolates are associated with increased cell wall thickness and suboptimal bacterial internalisation or lysis by human phagocytes. In total, 95 isolates were evaluated. Original vancomycin MICs were determined by Etest. The susceptibility of S. aureus isolates to killing by phagocytes was assessed in a human whole blood assay. Internalisation of bacterial cells by phagocytes was investigated by flow cytometry. Cell wall thickness was evaluated by transmission electron microscopy. Genotypic analysis of S. aureus isolates was performed using a DNA microarray system. Vancomycin MICs were significantly higher (P=0.006) in isolates that were killed suboptimally (killing index <60%) compared with those killed efficiently (killing index >70%) and tended to correlate inversely (P=0.08) with the killing indices. Isolates in both killing groups were internalised by human neutrophils and monocytes with comparable efficiency. The cell wall was significantly thicker (P=0.03) in isolates in the low killing group. No genotypic differences were found between the isolates in both killing groups. In summary, high vancomycin MICs in S. aureus bacteraemia isolates were associated with increased cell wall thickness and reduced intracellular killing by phagocytes. PMID:27056298

  4. Accurate method for measurement of pipe wall thickness using a circumferential guided wave generated and detected by a pair of noncontact transducers

    NASA Astrophysics Data System (ADS)

    Nishino, H.; Taniguchi, Y.; Yoshida, K.

    2012-05-01

    A noncontact method of an accurate estimation of a pipe wall thickness using a circumferential (C-) Lamb wave is presented. The C-Lamb waves circling along the circumference of pipes are transmitted and received by the critical angle method using a pair of noncontact air-coupled ultrasonic transducers. For the accurate estimation of a pipe wall thickness, the accurate measurement of the angular wave number that changes minutely owing to the thickness must be achieved. To achieve the accurate measurement, a large number of tone-burst cycles are used so as to superpose the C-Lamb wave on itself along its circumferential orbit. In this setting, the amplitude of the superposed region changes considerably with the angular wave number, from which the wall thickness can be estimated. This paper presents the principle of the method and experimental verifications. As results of the experimental verifications, it was confirmed that the maximum error between the estimates and the theoretical model was less than 10 micrometers.

  5. Contribution of CT quantified emphysema, air trapping and airway wall thickness on pulmonary function in male smokers with and without COPD.

    PubMed

    Mohamed Hoesein, Firdaus A A; de Jong, Pim A; Lammers, Jan-Willem J; Mali, Willem P Th M; Mets, Onno M; Schmidt, Michael; de Koning, Harry J; Aalst, Carlijn van der; Oudkerk, Matthijs; Vliegenthart, Rozemarijn; Ginneken, Bram van; van Rikxoort, Eva M; Zanen, Pieter

    2014-09-01

    Emphysema, airway wall thickening and air trapping are associated with chronic obstructive pulmonary disease (COPD). All three can be quantified by computed tomography (CT) of the chest. The goal of the current study is to determine the relative contribution of CT derived parameters on spirometry, lung volume and lung diffusion testing. Emphysema, airway wall thickening and air trapping were quantified automatically on CT in 1,138 male smokers with and without COPD. Emphysema was quantified by the percentage of voxels below -950 Hounsfield Units (HU), airway wall thickness by the square root of wall area for a theoretical airway with 10 mm lumen perimeter (Pi10) and air trapping by the ratio of mean lung density at expiration and inspiration (E/I-ratio). Spirometry, residual volume to total lung capacity (RV/TLC) and diffusion capacity (Kco) were obtained. Standardized regression coefficients (β) were used to analyze the relative contribution of CT changes to pulmonary function measures. The independent contribution of the three CT measures differed per lung function parameter. For the FEV1 airway wall thickness was the most contributing structural lung change (β = -0.46), while for the FEV1/FVC this was emphysema (β = -0.55). For the residual volume (RV) air trapping was most contributing (β = -0.35). Lung diffusion capacity was most influenced by emphysema (β = -0.42). In a cohort of smokers with and without COPD the effect of different CT changes varies per lung function measure and therefore emphysema, airway wall thickness and air trapping need to be taken in account.

  6. Management of voluminous abdominal incisional hernia.

    PubMed

    Bouillot, J-L; Poghosyan, T; Pogoshian, T; Corigliano, N; Canard, G; Veyrie, N

    2012-10-01

    Incisional hernia is one of the classic complications after abdominal surgery. The chronic, gradual increase in size of some of these hernias is such that the hernia ring widens to a point where there is a loss of substance in the abdominal wall, herniated organs can become incarcerated or strangulated while poor abdominal motility can alter respiratory function. The surgical treatment of small (<5 cm) incisional hernias is safe and straightforward, by either laparotomy or laparoscopy. For large hernias, surgical repair is often difficult. After reintegration of herniated viscera into the abdominal cavity, the abdominal wall defect must be closed anatomically in order to restore the function to the abdominal wall. Prosthetic reinforcement of the abdominal wall is mandatory for long-term successful repair. There are multiple techniques for prosthetic hernia repair, but placement of Dacron mesh in the retromuscular plane is our preference. PMID:23137643

  7. Precise Measurement of Pipe Wall Thickness in Noncontact Manner Using a Circumferential Lamb Wave Generated and Detected by a Pair of Air-Coupled Transducers

    NASA Astrophysics Data System (ADS)

    Nishino, Hideo; Asano, Tadashi; Taniguchi, Yuta; Yoshida, Kenichi; Ogawa, Hitoshi; Takahashi, Masakazu; Ogura, Yukio

    2011-07-01

    In this paper, we present a novel method of accurately estimating pipe wall thickness by detecting the minute difference in the angular wave number of a circumferential (C-) Lamb wave. A C-Lamb wave circling along a circumference of a pipe is transmitted and received by a pair of noncontact air-coupled ultrasonic transducers. For the accurate detection of the angular wave number, a large number of tone-burst cycles are used so as to superpose the C-Lamb wave on itself along its circumferential orbit. In this setting, the amplitude of the superposed region changes considerably with the angular wave number, from which the wall thickness can be estimated. This method is very useful to monitor the integrity of piping in high-temperature environments because of its noncontact nature. The principle of the method and experimental verification are shown.

  8. Reduction of Influence of Decrease in Signal-to-Noise Ratio in Measurement of Change in Thickness of Arterial Wall Due to Heartbeat

    NASA Astrophysics Data System (ADS)

    Hasegawa, Hideyuki; Kanai, Hiroshi; Hoshimiya, Nozomu; Koiwa, Yoshiro

    2000-05-01

    To diagnose early-stage atherosclerosis, for the local evaluation of the elasticity of the arterial wall it is necessary to increase the spatial resolution in the axial direction of the artery to several millimeters, which corresponds to the size of the lesion on the surface of the arterial wall. For this purpose, we previously proposed a method for measuring the small change in thickness of the arterial wall during the cardiac cycle [H. Kanai ηl.: IEEE Trans. UFFC 43 (1996) 791, H. Kanai ηl.: IEEE Trans. UFFC 44 (1997) 752 and H. Hasegawa ηl.: Electron. Lett. 33 (1997) 340]. The change in thickness cannot be measured from conventional B-mode or M-mode images because of its small amplitude of less than 100 micrometers. Though the change in thickness is useful for in vivo assessment of the local elasticity of the arterial wall, in some cases successful measurements based on only two consecutive echos fail because of the low signal-to-noise ratio (SNR) of the echos. To realize the practical use of the proposed method, this problem must be overcome. In this paper, we propose a method that is more robust in the presence of noise. In this method, more than two echos are employed to estimate their phase shift for reducing the influence of low SNR. Simulations provide an optimal value of the estimation period for each SNR. By evaluating the SNR of in vivo experimental data, the optimal estimation period is determined. In in vivo experiments using an optimal estimation period of 20 ms, the change in thickness can be measured with good reproducibility even in the case of a low SNR of 28 dB.

  9. Short-axis epicardial volume change is a measure of cardiac left ventricular short-axis function, which is independent of myocardial wall thickness.

    PubMed

    Ugander, Martin; Carlsson, Marcus; Arheden, Håkan

    2010-02-01

    Fractional shortening (FS) by echocardiography is considered to represent the short-axis contribution to the stroke volume (SV), also called short-axis function. However, FS is mathematically coupled to the amount of myocardium, since it rearranges during atrioventricular plane displacement (AVPD). The SV is the sum of the volumes generated by 1) reduction in outer volume of the heart, and 2) inner AVPD. The long-axis contribution to the SV is generated by AVPD, and thus the short-axis contribution is the remaining outer volume change of the heart, which should be unrelated to myocardial wall thickness. We hypothesized that both endocardial and midwall shortening indexed to SV are dependent on myocardial wall thickness, whereas epicardial volume change (EVC) indexed to SV is not. Twelve healthy volunteers (normals), 12 athletes, and 12 patients with dilated cardiomyopathy (ejection fraction < 30%) underwent cine cardiac magnetic resonance imaging. Left ventricular long-axis function was measured as the portion of the SV, in milliliters, generated by AVPD. EVC was defined as SV minus long-axis function. Endocardial and midwall shortening were measured in a midventricular short-axis slice. Endocardial shortening/SV and midwall shortening/SV both varied in relation to end-diastolic myocardial wall thickness (R(2) = 0.16, P = 0.008 and R(2) = 0.14, P = 0.012, respectively), whereas EVC/SV did not (R(2) = 0.00, P = 0.37). FS is dependent on myocardial wall thickness, whereas EVC is not and therefore represents true short-axis function. This is not surprising considering that FS is mainly caused by rearrangement of myocardium secondary to long-axis function. FS is therefore not synonymous with short-axis function.

  10. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Ziaja, K; Sedlak, L; Urbanek, T; Kostyra, J; Ludyga, T

    2000-01-01

    The reported incidence of inflammatory abdominal aortic aneurysm (IAAA) is from 2% to 14% of patients with abdominal aortic aneurysm and the etiology of this disease is still discussed--according to the literature several pathogenic theories have been proposed. From 1992 to 1997 32 patients with IAAA were operated on. The patients were mostly symptomatic--abdominal pain was present in 68.75% cases, back pain in 31.25%, fever in 12.5% and weight loss in 6.25% of the operated patients. In all the patients ultrasound examination was performed, in 4 patients CT and in 3 cases urography. All the patients were operated on and characteristic signs of inflammatory abdominal aortic aneurysm like: thickened aortic wall, perianeurysmal infiltration or retroperitoneal fibrosis with involvement of retroperitoneal structures were found. In all cases surgery was performed using transperitoneal approach; in three cases intraoperatively contiguous abdominal organs were injured, which was connected with their involvement into periaortic inflammation. In 4 cases clamping of the aorta was done at the level of the diaphragmatic hiatus. 3 patients (9.37%) died (one patient with ruptured abdominal aortic aneurysm). Authors present diagnostic procedures and the differences in the surgical tactic, emphasizing the necessity of the surgical therapy in patients with inflammatory abdominal aortic aneurysm.

  11. [Abdominal approaches and drainages of the abdominal cavity].

    PubMed

    Hagel, C; Schilling, M

    2006-04-01

    Appropriate access to the abdominal cavity is the first and crucial step for successful abdominal surgical intervention. In planning the incision, several variables have to be considered, such as anatomy of the abdominal wall, localization of the target organ, and individual conditions (previous incisions, minimal access surgery, etc). Medial laparotomy is the preferred incision for emergency cases and ill-defined pathologies, allowing access and hence exploration to all quadrants. Transverse laparotomies give superior access to the dorsal and right aspects of the liver and cause less pain in patients unfit for regional anesthetic procedures. Draining of the abdominal cavity is used after various resective and reconstructive procedures, but there is little evidence for its use in a number of operations such as gastric, hepatic, and colorectal resections. Advantages and disadvantages of different abdominal wall incisions and drainages are discussed.

  12. Thickness estimation of the subcutaneous fat using coaxial probe.

    PubMed

    Ramezani, Mohammad Hossein; Nadimi, Esmaeil S

    2016-03-01

    In this Letter, a non-invasive method for thickness estimation of the subcutaneous fat layer of abdominal wall is presented by using a coaxial probe. Fat layer has the highest impact on the averaged attenuation parameter of the abdominal wall due to its high thickness and low permittivity. The abdominal wall is modelled as a multi-layer medium and an analytical model for the probe is derived by calculation of its aperture admittance facing to this multi-layer medium. The performance of this model is then validated by a numerical simulation using finite-difference-time-domain (FDTD) analysis. Simulation results show the high impact of the probe dimension and fat layer thickness on the sensitivity of the measured permittivity. The authors further investigate this sensitivity by statistical analysis of the permittivity variations. Finally, measuring in different locations relative to the body surface is presented as a solution to estimate the fat layer thickness in the presence of uncertainty of model parameters.

  13. Thickness estimation of the subcutaneous fat using coaxial probe.

    PubMed

    Ramezani, Mohammad Hossein; Nadimi, Esmaeil S

    2016-03-01

    In this Letter, a non-invasive method for thickness estimation of the subcutaneous fat layer of abdominal wall is presented by using a coaxial probe. Fat layer has the highest impact on the averaged attenuation parameter of the abdominal wall due to its high thickness and low permittivity. The abdominal wall is modelled as a multi-layer medium and an analytical model for the probe is derived by calculation of its aperture admittance facing to this multi-layer medium. The performance of this model is then validated by a numerical simulation using finite-difference-time-domain (FDTD) analysis. Simulation results show the high impact of the probe dimension and fat layer thickness on the sensitivity of the measured permittivity. The authors further investigate this sensitivity by statistical analysis of the permittivity variations. Finally, measuring in different locations relative to the body surface is presented as a solution to estimate the fat layer thickness in the presence of uncertainty of model parameters. PMID:27222737

  14. 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.

  15. 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

    2016-10-01

    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.

  16. Laparoscopic excision of intra-abdominal paragonimiasis.

    PubMed

    Kim, Jun-Young; Kang, Chang-Moo; Choi, Gi-Hong; Yang, Woo-Ick; Sim, Seo-Bo; Kwon, Ji-Eun; Kim, Kyung-Sik; Choi, Jin-Sub; Lee, Woo-Jung; Kim, Byong-Ro

    2007-12-01

    Lung fluke, Paragonimus westermani of Paragonimus species usually are accompanied by a persistent cough, hemoptysis, and chest pain. Extrapulmonary paragonimiasis caused by ectopic parasites in aberrant locations such as the abdominal wall, abdominal organs, and brain has been reported and the most commonly involved extrapulmonary organ is the brain. We present a case of 56-year-old male patient with intra-abdominal paragonimiasis who underwent laparoscopic excision of abdominal granuloma caused by parasite infection. An intra-abdominal mass associated with eosinophilia might be related to parasite infection. A laparoscopic approach is the most appropriate treatment modality in such benign abdominal pathology.

  17. 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.

  18. Effects of cross-linking, capsule wall thickness, and compound hydrophobicity on aroma release from complex coacervate microcapsules.

    PubMed

    Leclercq, Segolene; Milo, Christian; Reineccius, Gary A

    2009-02-25

    Microcapsules were produced by complex coacervation with a gelatin-gum acacia wall and medium-chain-triglyceride core. Dry capsules were partially rehydrated and then loaded with model aroma compounds covering a range of volatility, hydrophobicity, and molecular structure. An experimental design was prepared to evaluate the effects of cross-linking, wall/core ratio, and volatile load level on aroma release from capsules in a hot, aqueous environment. The real-time release on rehydration was measured by monitoring the headspace of a vessel containing the capsules to proton transfer reaction mass spectrometry (PTR-MS). Data collected showed no effects of cross-linking or wall/core ratio on volatile release in hot water for any of the volatiles studied. When comparing real-time release of the prepared coacervates to a spray-dried equivalent, there was no difference in the release from hot water but the release was slower when coacervates were added to ambient-temperature water. We found volatile release to be primarily determined by compound partition coefficients (oil/water and water/air) and temperature.

  19. Gold-Based Cubic Nanoboxes with Well-Defined Openings at the Corners and Ultrathin Walls Less Than Two Nanometers Thick.

    PubMed

    Sun, Xiaojun; Kim, Junki; Gilroy, Kyle D; Liu, Jingyue; König, Tobias A F; Qin, Dong

    2016-08-23

    We report a facile synthesis of Au-based cubic nanoboxes as small as 20 nm for the outer edge length, together with well-defined openings at the corners and walls fewer than 10 atomic layers (or <2 nm) in thickness. The success relies on the selective formation of Ag2O at the corners of Ag nanocubes, followed by the conformal deposition of Au on the side faces in a layer-by-layer fashion. When six atomic layers of Au are formed on the side faces to generate Ag@Au6L core-shell nanocubes, we can selectively remove the Ag2O patches at the corner sites using a weak acid, making it possible to further remove the Ag core by H2O2 etching without breaking the ultrathin Au shell. This synthetic approach works well for Ag nanocubes of 38 and 18 nm in edge length, and the wall thickness of the nanoboxes can be controlled down to 2 nm. The resultant Au nanoboxes exhibit strong plasmonic absorption in the near-infrared region, consistent with computational simulations. PMID:27458731

  20. Ordered hexagonal mesoporous aluminosilicates synthesized using zeolite as precursor and the wall-thickness tuned by pH control

    NASA Astrophysics Data System (ADS)

    Wang, Chunlei; Zhu, Guangshang; Shang, Tiecun; Cai, Xiaohui; Liu, Chengzhan; Li, Nan; Wei, Yuhong; Li, Jian; Zhang, Weiwei; Qiu, Shilun

    2005-07-01

    High aluminium content mesoporous aluminosilicates MAS-X1 and MAS-X3 have been successfully synthesized using zeolite FAU-X as precursors and triblock copolymer pluronic P123 as structure directing agent. Samples have been characterized by XRD, TEM, nitrogen adsorption/desorption, 27Al MAS NMR, and ICP element analysis techniques. The salt, NaCl, which was introduced by dissolving the zeolite FAU-X, played an important role in the synthesis of high order sample. The secondary growth of the wall was considered to occur after the pH value had been increased up to five.

  1. Augmentation of Left Ventricular Wall Thickness With Alginate Hydrogel Implants Improves Left Ventricular Function and Prevents Progressive Remodeling in Dogs With Chronic Heart Failure

    PubMed Central

    Sabbah, Hani N.; Wang, Mengjun; Gupta, Ramesh C.; Rastogi, Sharad; Ilsar, Itamar; Sabbah, Michael S.; Kohli, Smita; Helgerson, Sam; Lee, Randall J.

    2013-01-01

    Objectives The study tested the hypothesis that augmentation of the left ventricular (LV) wall thickness with direct intramyocardial injections of alginate hydrogel implants (AHI) reduces LV cavity size, restores LV shape, and improves LV function in dogs with heart failure (HF). Background Progressive LV dysfunction, enlargement, and chamber sphericity are features of HF associated with increased mortality and morbidity. Methods Studies were performed in 14 dogs with HF produced by intracoronary microembolizations (LV ejection fraction [EF] <30%). Dogs were randomized to AHI treatment (n = 8) or to sham-operated control (n = 6). During an open-chest procedure, dogs received either intramyocardial injections of 0.25 to 0.35 ml of alginate hydrogel (Algisyl-LVR, LoneStar Heart, Inc., Laguna Hills, California) or saline. Seven injections were made ∼1.0 to 1.5 cm apart (total volume 1.8 to 2.1 ml) along the circumference of the LV free wall halfway between the apex and base starting from the anteroseptal groove and ending at the posteroseptal groove. Hemodynamic and ventriculographic measurements were made before treatment (PRE) and repeated post-surgery for up to 17 weeks (POST). Results Compared to control, AHI significantly reduced LV end-diastolic and end-systolic volumes and improved LV sphericity. AHI treatment significantly increased EF (26 ± 0.4% at PRE to 31 ± 0.4% at POST; p < 0.05) compared to the decreased EF seen in control dogs (27 ± 0.3% at PRE to 24 ± 1.3% at POST; p < 0.05). AHI treatment was well tolerated and was not associated with increased LV diastolic stiffness. Conclusions In HF dogs, circumferential augmentation of LV wall thickness with AHI improves LV structure and function. The results support continued development of AHI for the treatment of patients with advanced HF. PMID:23998003

  2. Direct measurement of wall slip and slip layer thickness of non-Brownian hard-sphere suspensions in rectangular channel flows

    NASA Astrophysics Data System (ADS)

    Jesinghausen, Steffen; Weiffen, Rene; Schmid, Hans-Joachim

    2016-09-01

    Wall slip is a long-known phenomenon in the field of rheology. Nevertheless, the origin and the evolution are not completely clear yet. Regarding suspensions, the effect becomes even more complicated, because different mechanisms like pure slip or slip due to particle migration have to be taken into account. Furthermore, suspensions themselves show many flow anomalies and the isolation of slip is complicated. In order to develop working physical models, further insight is necessary. In this work, we measured experimentally the wall slip velocities of different highly filled suspensions in a rectangular slit die directly with respect to the particle concentration and the particle size. The slip velocities were obtained using a particle image velocimetry (PIV) system. The suspensions consisting of a castor oil-cinnamon oil blend and PMMA particles were matched in terms of refractive indexes to appear transparent. Hereby, possible optical path lengths larger than 15 mm were achieved. The slip velocities were found to be in a quadratic relation to the wall shear stress. Furthermore, the overall flow rate as well as the particle concentration has a direct influence on the slip. Concerning the shear stress, there seem to be two regions of slip with different physical characteristics. Furthermore, we estimated the slip layer thickness directly from the velocity profiles and propose a new interpretation. The PIV technique is used to investigate the viscosity and implicit the concentration profile in the slit die. It is shown that the particle migration process is quite fast.

  3. 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.

  4. Effect of alpha lipoic acid co-administration on structural and immunohistochemical changes in subcutaneous tissue of anterior abdominal wall of adult male albino rat in response to polypropylene mesh implantation

    PubMed Central

    Mazroa, Shireen A; Asker, Samar A; Asker, Waleed; Abd Ellatif, Mohamed

    2015-01-01

    Polypropylene mesh is commonly used in the treatment of abdominal hernia. Different approaches were addressed to improve their tissue integration and consequently reduce long-term complications. This study aimed to investigate the effect of alpha-lipoic acid (ALA) co-administration on structural and immunohistochemical (IHC) changes in the subcutaneous tissues of the anterior abdominal wall of the adult rat in response to polypropylene mesh implantation. Forty adult male albino rats were divided into: group I (control), group II (receiving ALA), group III (polypropylene mesh implantation) and group IV (mesh implantation + ALA co-administration). After 4 weeks, subcutaneous tissue samples were prepared for light microscopy and IHC study of CD34 as a marker for angiogenesis. In groups I and II rats, positive CD34 expression was demonstrated by IHC reaction, localized to endothelial cells lining small blood vessels. Group III showed an excess inflammatory reaction, deposition of both regular and irregularly arranged collagen fibres around mesh pores and few elastic fibres. CD34-positive was detected not only in cells lining small blood vessels but also in other cells scattered in the connective tissue indicating angiogenesis. In group IV, ALA co-administration resulted in less inflammatory reaction, regular collagen deposition, enhanced elastic fibres synthesis and a significant increase in CD34-positive cells and small blood vessels reflecting improved angiogenesis. ALA co-administration with polypropylene mesh implantation controlled the inflammatory reaction, helped regular collagen deposition, enhanced elastic fibres synthesis and improved angiogenesis in the subcutaneous tissue of anterior abdominal wall of adult albino rats, suggesting a possible role of ALA in optimizing mesh integration in subcutaneous tissue. PMID:25891652

  5. Effect of alpha lipoic acid co-administration on structural and immunohistochemical changes in subcutaneous tissue of anterior abdominal wall of adult male albino rat in response to polypropylene mesh implantation.

    PubMed

    Mazroa, Shireen A; Asker, Samar A; Asker, Waleed; Abd Ellatif, Mohamed

    2015-06-01

    Polypropylene mesh is commonly used in the treatment of abdominal hernia. Different approaches were addressed to improve their tissue integration and consequently reduce long-term complications. This study aimed to investigate the effect of alpha-lipoic acid (ALA) co-administration on structural and immunohistochemical (IHC) changes in the subcutaneous tissues of the anterior abdominal wall of the adult rat in response to polypropylene mesh implantation. Forty adult male albino rats were divided into: group I (control), group II (receiving ALA), group III (polypropylene mesh implantation) and group IV (mesh implantation + ALA co-administration). After 4 weeks, subcutaneous tissue samples were prepared for light microscopy and IHC study of CD34 as a marker for angiogenesis. In groups I and II rats, positive CD34 expression was demonstrated by IHC reaction, localized to endothelial cells lining small blood vessels. Group III showed an excess inflammatory reaction, deposition of both regular and irregularly arranged collagen fibres around mesh pores and few elastic fibres. CD34-positive was detected not only in cells lining small blood vessels but also in other cells scattered in the connective tissue indicating angiogenesis. In group IV, ALA co-administration resulted in less inflammatory reaction, regular collagen deposition, enhanced elastic fibres synthesis and a significant increase in CD34-positive cells and small blood vessels reflecting improved angiogenesis. ALA co-administration with polypropylene mesh implantation controlled the inflammatory reaction, helped regular collagen deposition, enhanced elastic fibres synthesis and improved angiogenesis in the subcutaneous tissue of anterior abdominal wall of adult albino rats, suggesting a possible role of ALA in optimizing mesh integration in subcutaneous tissue.

  6. Abdominal Pain

    MedlinePlus

    ... can help the overall situation for the child. Teaching kids self-hypnosis [8] or guided imagery [8a] ... related topics? Functional Abdominal Pain (English, French or Spanish)—from The North American Society for Pediatric Gastroenterology, ...

  7. Abdominal pain

    MedlinePlus

    Stomach pain; Pain - abdomen; Belly ache; Abdominal cramps; Bellyache; Stomachache ... Almost everyone has pain in the abdomen at some point. Most of the time, it is not serious. How bad your pain is ...

  8. A non-destructive experimental investigation of elastic plastic interfaces of autofrettaged thick-walled cylindrical aluminium high pressure vessels

    NASA Astrophysics Data System (ADS)

    Ma, Yanling; Zhang, Shu Yan; Goodway, Chris; Done, Robert; Evans, Beth; Kirichek, Oleg; Bowden, Zoë

    2012-09-01

    Positions of elastic plastic interfaces play a vital role in safe design and safe use of high pressure vessels. The ENGIN-X neutron diffractometer at the ISIS facility was used to measure the residual strain profiles in a series of aluminium vessels which had been subjected to different pressure levels. The positions of elastic plastic interfaces of the autofrettaged pressure vessels were identified. The results revealed that the residual strain magnitude and the depth of the plastic region will increase with increasing autofrettage pressure level. When autofrettage pressure produces an elastic-plastic boundary at a greater depth than the geometric mean position of the vessel wall, reverse yielding will occur, hence the loss of the vessels' elastic ability to its subsequent loading. The neutron experimental results agreed well with both the suggestions from existing literatures and the results from FE simulations.

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 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

  15. Novel synthesis of thick wall coatings of titania supported Bi poisoned Pd catalysts and application in selective hydrogenation of acetylene alcohols in capillary microreactors.

    PubMed

    Cherkasov, Nikolay; Ibhadon, Alex O; Rebrov, Evgeny V

    2015-04-21

    Catalysis in microreactors allows reactions to be performed in a very small volume, reducing the environmental problems and greatly intensifying the processes through easy pressure control and the elimination of heat- and mass-transfer limitations. In this study, we report a novel method for the controlled synthesis of micrometre-thick mesoporous TiO2 catalytic coatings on the walls of long channels (>1 m) of capillary microreactors in a single deposition step. The method uses elevated temperature and introduces a convenient control parameter of the deposition rate (displacement speed controlled by a stepper motor), which allows deposition from concentrated and viscous sols without channel clogging. A capillary microreactor wall-coated with titania supported Bi-poisoned Pd catalyst was obtained using the method and used for the semihydrogenation of 2-methyl-3-butyn-2-ol providing 93 ± 1.5% alkene yield for 100 h without deactivation. Although the coating method was applied only for TiO2 deposition, it is nonetheless suitable for the deposition of volatile sols. PMID:25749619

  16. The relationship between wall tension, lamellar thickness, and intercellular junctions in the fetal and adult aorta: its relevance to the pathology of dissecting aneurysm.

    PubMed

    Berry, C L; Sosa-Melgarejo, J A; Greenwald, S E

    1993-01-01

    It is known that the distribution of stress and strain in the vessel wall is not uniform. We believe that this explains the location of the plane of dissection in dissecting aneurysms of large elastic arteries. We have investigated the effects of non-uniformity of stress and strain on the thickness of each elastic lamella and on the distribution of intercellular junctions in the media of developing and adult rats, to seek evidence to support this hypothesis. Intercellular junctions were identified by transmission electron microscopy of whole wall sections. A morphometric study of elastic tissue distribution was made on an image analysis computer. Differences were analysed using one-way analysis of variance. There are between six and eight elastic lamellae in the aorta of rats. In the fetus, only the internal elastic lamella is complete; the others were not fully formed by term. In the adult, the inner five elastic lamellae were thicker than the remaining two or three, and smooth muscle cells in the thicker lamellar units had more cell-cell contacts of all types examined. These data support the concept of a difference in stress-resisting properties of the aortic wall on the junctions between the inner two-thirds and the outer third of the media. The findings indicate that, as proposed in theoretical models the innermost lamellae support the high tension. In the adult aorta, the structure is modified to enhance the capacity to resist stress in the internal two-thirds of the media.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8433211

  17. Abdominal Sepsis.

    PubMed

    De Waele, Jan J

    2016-08-01

    Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy. PMID:27363829

  18. Abdominal aortic aneurysm: from clinical imaging to realistic replicas.

    PubMed

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

    2014-01-01

    The goal of this work is to develop a framework for manufacturing nonuniform wall thickness replicas of abdominal aortic aneurysms (AAAs). The methodology was based on the use of computed tomography (CT) images for virtual modeling, additive manufacturing for the initial physical replica, and a vacuum casting process and range of polyurethane resins for the final rubberlike phantom. The average wall thickness of the resulting AAA phantom was compared with the average thickness of the corresponding patient-specific virtual model, obtaining an average dimensional mismatch of 180 μm (11.14%). The material characterization of the artery was determined from uniaxial tensile tests as various combinations of polyurethane resins were chosen due to their similarity with ex vivo AAA mechanical behavior in the physiological stress configuration. The proposed methodology yields AAA phantoms with nonuniform wall thickness using a fast and low-cost process. These replicas may be used in benchtop experiments to validate deformations obtained with numerical simulations using finite element analysis, or to validate optical methods developed to image ex vivo arterial deformations during pressure-inflation testing.

  19. 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: ...

  20. [Differential surgical treatment of victims with damage to the small and large intestines in a closed abdominal injury combined, depending on the prediction of traumatic disease course and morphological changes of the intestinal wall].

    PubMed

    Zaruts'kyĭ, Ia L; Denysenko, V M; Khomenko, I P; Levkivskyĭ, R H

    2013-08-01

    Use of differentiated surgical approach to the management of surgical treatment, depending on the degree of violation of systemic hemodynamics, the timing and volume of surgical procedures, depending on the prognosis of traumatic disease course of cardiac index, interventions in the small and large intestine depending on morphological changes of the intestinal wall by cardiac and stroke indexes, put method extra-enteric anastomosis in patients with damage to the small intestine and colon combined with closed abdominal injury permitted to reduce the rate of postoperative complications from 22.2 to 10.1%, mortality at 2.1 times in shock period (from 19.3 to 9.2%) and the overall mortality from 33.3 to 21.1%.

  1. Abdominal Aortic Aneurysms: Treatments

    MedlinePlus

    ... information Membership Directory (SIR login) Interventional Radiology Abdominal Aortic Aneurysms Interventional Radiologists Treat Abdominal Aneurysms Nonsurgically Interventional radiologists ...

  2. Myocardial wall-thickness transducer

    NASA Technical Reports Server (NTRS)

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

    1976-01-01

    Device consists of highly compliant circular beam attached to piezoresistive strain gage and barbed needle. Radial deflection of myocardium is measured with minimal disturbance of normal heart functions.

  3. 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

  4. 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.

  5. Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index.

    PubMed

    Polzer, Stanislav; Gasser, T Christian

    2015-12-01

    A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach. PMID:26631334

  6. Retrospective analysis of a VACM (vacuum-assisted closure and mesh-mediated fascial traction) treatment manual for temporary abdominal wall closure - results of 58 consecutive patients.

    PubMed

    Beltzer, Christian; Eisenächer, Alexander; Badendieck, Steffen; Doll, Dietrich; Küper, Markus; Lenz, Stefan; Krapohl, Björn Dirk

    2016-01-01

    Einleitung: Das optimale Behandlungskonzept eines temporären Bauchdeckenverschlusses (temporary abdominal closure, TAC) bei kritisch kranken viszeralchirurgischen Patienten mit offenem Abdomen („open abdomen“, OA) ist weiterhin unklar. Durch eine VACM-Therapie (vacuum-assisted closure and mesh-mediated fascial traction) scheinen sich gegenüber anderen Verfahren des TAC höhere Faszienverschlussraten (delayed primary fascial closure rate, FCR) realisieren zu lassen. Material und Methoden: Patienten unserer Klinik (n=58), welche in den Jahren 2005 bis 2008 mittels eines VAC/VACM-Behandlungsmanuals behandelt wurden, wurden retrospektiv analysiert. Ergebnisse: Die FCR aller Patienten betrug insgesamt 48,3% (95%-Konfidenzintervall: 34,95–61,78). Bei Patienten, bei denen im Verlauf ein Vicryl-Netz auf Faszienebene implantiert wurde (VACM-Therapie), konnte eine FCR von 61,3% realisiert werden. Die Letalität der mittels VACM therapierten Patienten betrug 45,2% (95%-KI: 27,32–63,97).Schlussfolgerung: Die Ergebnisse der eigenen Untersuchung bestätigen bisherige Studienergebnisse, die eine akzeptable FCR bei non-trauma-Patienten durch Anwendung der VACM-Therapie zeigen konnten. Die VACM-Therapie scheint aktuell Therapiekonzept der ersten Wahl bei Patienten mit OA und Indikation zum TAC zu sein.

  7. Retrospective analysis of a VACM (vacuum-assisted closure and mesh-mediated fascial traction) treatment manual for temporary abdominal wall closure – results of 58 consecutive patients

    PubMed Central

    Beltzer, Christian; Eisenächer, Alexander; Badendieck, Steffen; Doll, Dietrich; Küper, Markus; Lenz, Stefan; Krapohl, Björn Dirk

    2016-01-01

    Introduction: The optimal treatment concept for temporary abdominal closure (TAC) in critically ill visceral surgery patients with open abdomen (OA) continues to be unclear. The VACM (vacuum-assisted closure and mesh-mediated fascial traction) therapy seems to permit higher delayed primary fascial closure rates (FCR) than other TAC procedures. Material and methods: Patients of our clinic (n=58) who were treated by application of a VAC/VACM treatment manual in the period from 2005 to 2008 were retrospectively analysed. Results: The overall FCR of all patients was 48.3% (95% confidence interval: 34.95–61.78). An FCR of 61.3% was achieved in patients who had a vicryl mesh implanted at the fascial level (VACM therapy) in the course of treatment. Mortality among patients treated with VACM therapy was 45.2% (95% CI: 27.32–63.97). Conclusions: The results of our own study confirm the results of previous studies which showed an acceptable FCR among non-trauma patients who were treated with VACM therapy. VACM therapy currently appears to be the treatment regime of choice for patients with OA requiring TAC. PMID:27547691

  8. [Morphological and functional parameters of the left ventricle (mass, wall thickness and end-systolic stress) in school children with different levels of blood pressure, at rest and during maximal exercise].

    PubMed

    Muñoz, S; Soltero, I; Onorato, E; Pietri, C; Zambrano, F

    1990-01-01

    Echocardiographically determined left ventricular mass, diastolic septal and posterior wall thickness and end-systolic wall stress, as well as electrocardiographic indexes of left ventricular enlargement (Sokolow-Lyon index and Romhilt-Estes score) and of left atrial enlargement (P terminal index) were correlated with resting and exercise systolic and diastolic blood pressures, and with several parameters of body size (weight, height, body surface area, Quetelet index), in 130 school children (61 boys, 69 girls) 6 to 15 years of age. Parameters of body size had a positive correlation both with systolic and diastolic blood pressures and with parameters of left ventricular size. Thus, the latter were adjusted for body surface area, for correlation with blood pressure. Left ventricular mass and diastolic septal and posterior wall thickness had a very poor correlation with resting and exercise diastolic blood pressures. Left ventricular mass and diastolic posterior wall thickness had a significantly higher correlation with peak exercise systolic blood pressure than with resting systolic blood pressure. End-systolic wall stress had a positive correlation with resting diastolic and systolic blood pressures. Electrocardiographic parameters of left ventricular and left atrial enlargement had a very poor correlation with resting and exercise blood pressure. Our findings suggest that early in life left ventricular mass and wall thickness are more closely related to maximal systolic blood pressure during physical exercise than to blood pressure in basal conditions. The electrocardiogram is an insensitive method to detect early modifications of left ventricular size in relation to different levels of blood pressure. The echocardiogram is the method of choice for this purpose.

  9. 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.

  10. 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

  11. Investigating the effect of tamsulosin on the measurement of bladder wall thickness and International Prostate Symptom Score in benign prostatic hyperplasia

    PubMed Central

    Eghbali, Kamyar; Shayegan, Mohammad Reza; Kianoush, Sina

    2013-01-01

    Introduction: According to previous studies, aging, gender, bladder volume and pathological states, such as bladder outflow obstruction, affect bladder wall thickness (BWT). The aim of this study was to evaluate the correlation between BWT and the International Prostatic Symptom Score (IPSS) in patients with benign prostatic hyperplasia (BPH) before and after tamsulosin treatment. Methods: In this study, 60 BPH patients were included. After obtaining informed consent, data were gathered using questionnaires to determine IPSS. After that, prostate-specific antigen was measured and a clinical examination, including a digital rectal examination, was performed for all patients. BWT was determined by transabdominal ultrasound. Finally, all patients were treated with tamsulosin (0.4 mg/day) for 2 months. After completing treatment, the IPSS and BWT were measured again and compared with the initial findings. Results: In total, 44 patients completed treatment. Patients aged 61.7 ± 9.2 years old. The mean ± standard deviation of IPSS and BWT were 14.6 ± 5.0 and 5.36 ± 1.28 mm before treatment, while they significantly (p < 0.0001) decreased to 8.2 ± 4.7 and 4.69 ± 1.23 mm, respectively, after treatment. Chi-square test showed that the decrease in BWT was significantly correlated with the improvement in IPSS (p = 0.002; r = 0.449). Conclusion: After treatment with tamsulosin, patients experienced a reduction in their BWT which was significantly correlated with improvement in their IPSS. We conclude that transabdominal evaluation of BWT could be included in the follow-up assessment in BPH. PMID:23766833

  12. 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

  13. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  14. [The abdominal drop flap].

    PubMed

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

    2015-08-01

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

  15. 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.

  16. An Experimental and Numerical Comparison of the Rupture Locations of an Abdominal Aortic Aneurysm

    PubMed Central

    Doyle, Barry J.; Corbett, Timothy J.; Callanan, Anthony; Walsh, Michael T.; Vorp, David A.; McGloughlin, Timothy M.

    2009-01-01

    Purpose: To identify the rupture locations of idealized physical models of abdominal aortic aneurysm (AAA) using an in-vitro setup and to compare the findings to those predicted numerically. Methods: Five idealized AAAs were manufactured using Sylgard 184 silicone rubber, which had been mechanically characterized from tensile tests, tear tests, and finite element analysis. The models were then inflated to the point of rupture and recorded using a high-speed camera. Numerical modeling attempted to confirm these rupture locations. Regional variations in wall thickness of the silicone models was also quantified and applied to numerical models. Results: Four of the 5 models tested ruptured at inflection points in the proximal and distal regions of the aneurysm sac and not at regions of maximum diameter. These findings agree with high stress regions computed numerically. Wall stress appears to be independent of wall thickness, with high stress occurring at regions of inflection regardless of wall thickness variations. Conclusion: According to these experimental and numerical findings, AAAs experience higher stresses at regions of inflection compared to regions of maximum diameter. Ruptures of the idealized silicone models occurred predominantly at the inflection points, as numerically predicted. Regions of inflection can be easily identified from basic 3-dimensional reconstruction; as ruptures appear to occur at inflection points, these findings may provide a useful insight into the clinical significance of inflection regions. This approach will be applied to patient-specific models in a future study. PMID:19642790

  17. 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

  18. Relationship between preoperative magnetic resonance imaging and surgical findings: aneurysm wall thickness on high-resolution T1-weighted imaging and contact with surrounding tissue on steady-state free precession imaging.

    PubMed

    Tenjin, Hiroshi; Tanigawa, Seisuke; Takadou, Michiko; Ogawa, Takahiro; Mandai, Ayako; Nanto, Masataka; Osaka, Yasuhiko; Nakahara, Yoshikazu; Umeda, Masahiro; Higuchi, Toshihiro

    2013-01-01

    This study evaluated the aneurysm wall thickness by high-resolution T1-weighted imaging and the contact between the aneurysm and surrounding tissue by steady-state free precession (SSFP) imaging. The surgical findings were prospectively compared with these preoperative magnetic resonance (MR) imaging findings in 35 consecutive patients with 37 unruptured cerebral aneurysms (UCAs). The aneurysm wall was not visible in 13 UCAs, but was visible in 23. Subarachnoid space between the aneurysm and surrounding tissue was visible in 16 UCAs, a visible layer of cerebrospinal fluid (CSF) between the aneurysm and surrounding tissue in 12, and no visible layer in 7. MR imaging predicted the surgical findings in 29 UCAs (78%), showed different findings in six UCAs (16%), and two (5%) could not be evaluated due to insufficient quality of preoperative MR images. Among the UCAs with different findings, five UCAs had a partially thin wall even though high-resolution T1-weighted imaging had shown a visible wall, and one UCA showed less contact with the surrounding tissue even though the SSFP imaging had shown no visible CSF layer. In conclusion, high-resolution T1-weighted imaging and SSFP imaging provided significant additional preoperative information regarding UCAs and the surrounding tissue.

  19. Understanding noninguinal abdominal hernias in the athlete.

    PubMed

    Cabry, Robert J; Thorell, Erik; Heck, Keith; Hong, Eugene; Berkson, David

    2014-01-01

    Abdominal hernias are common with over 20 million hernia repairs performed worldwide. Inguinal hernias are the most common type of hernia. Inguinal and sports hernia have been discussed at length in recent literature, and therefore, they will not be addressed in this article. The noninguinal hernias are much less common but do occur, and knowledge of these hernias is important when assessing the athlete with abdominal pain. Approximately 25% of abdominal wall hernias are noninguinal, and new data show the order of frequency as umbilical, epigastric, incisional, femoral, and all others (i.e., Spigelian, obturator, traumatic). Return-to-play guidelines need to be tailored to the athlete and the needs of their sport. Using guidelines similar to abdominal strain injuries can be a starting point for the treatment plan. Laparoscopic repair is becoming more popular because of safety and efficacy, and it may lead to a more rapid return to play. PMID:24614421

  20. Magnetic Surgical Instruments for Robotic Abdominal Surgery.

    PubMed

    Leong, Florence; Garbin, Nicolo; Natali, Christian Di; Mohammadi, Alireza; Thiruchelvam, Dhan; Oetomo, Denny; Valdastri, Pietro

    2016-01-01

    This review looks at the implementation of magnetic-based approaches in surgical instruments for abdominal surgeries. As abdominal surgical techniques advance toward minimizing surgical trauma, surgical instruments are enhanced to support such an objective through the exploration of magnetic-based systems. With this design approach, surgical devices are given the capabilities to be fully inserted intraabdominally to achieve access to all abdominal quadrants, without the conventional rigid link connection with the external unit. The variety of intraabdominal surgical devices are anchored, guided, and actuated by external units, with power and torque transmitted across the abdominal wall through magnetic linkage. This addresses many constraints encountered by conventional laparoscopic tools, such as loss of triangulation, fulcrum effect, and loss/lack of dexterity for surgical tasks. Design requirements of clinical considerations to aid the successful development of magnetic surgical instruments, are also discussed.

  1. 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.

  2. 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.

  3. 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

  4. Abdominal cerebrospinal fluid pseudocysts.

    PubMed

    Erşahin, Y; Mutluer, S; Tekeli, G

    1996-12-01

    Abdominal cerebrospinal fluid pseudocyst in an infrequent complication of ventriculoperitoneal (VP) shunts. We reviewed ten patients with abdominal pseudocyst. There were five girls and five boys, aged between 4 months and 14 years. The number of shunt procedures prior to the presentation varied between one and five. Only one patient had had a previous shunt infection. No patients had undergone prior abdominal surgery other than VP shunting. The time from the last shunting procedure to the development of abdominal pseudocyst ranged from 3 weeks to 5 years. Presenting symptoms and signs were mainly related to abdominal complaints in all patients. Three patients also had signs of shunt malfunction. The diagnosis was made by ultrasound in all patients. Shunt infection was determined in six patients. Repositioning if the peritoneal catheter seemed to have a higher rate of recurrence. The diagnosis of abdominal pseudocyst should be considered in VP-shunted patients presenting with abdominal complaints.

  5. 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

  6. 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.

  7. Pleuropulmonary and abdominal paragonimiasis: CT and ultrasound findings

    PubMed Central

    Shim, S S; Kim, Y; Lee, J K; Lee, J H; Song, D E

    2012-01-01

    Objectives The purpose of this study was to review radiological images of patients with Paragonimus westermani (PW) that simultaneously involved the chest and abdomen. Methods Our study included four patients with serologically and histopathologically confirmed paragonimiasis. Abdomen CT (n=3) and chest CT (n=3) scans were available, and abdominal wall ultrasonography was performed in all patients. We retrospectively reviewed the clinical, radiological and histopathological findings of these patients. Results The most common abdominal CT findings were ascites and intraperitoneal or abdominal wall nodules. Low-attenuated serpentine lesions of the liver were another common and relatively specific feature. Conclusion Radiologists should consider the possibility of PW when these abdominal CT findings are noted, especially with pleural effusion or subpleural nodules in patients with initial abdominal symptoms. PMID:22457403

  8. Laparoscopic Bullet Removal in a Penetrating Abdominal Gunshot

    PubMed Central

    Koulas, Spyridon; Tsimoyiannis, Ioannis

    2016-01-01

    Penetrating abdominal trauma has been traditionally treated by exploratory laparotomy. Nowadays laparoscopy has become an accepted practice in hemodynamically stable patient without signs of peritonitis. We report a case of a lower anterior abdominal gunshot patient treated laparoscopically. A 32-year-old male presented to the Emergency Department with complaint of gunshot penetrating injury at left lower anterior abdominal wall. The patient had no symptoms or obvious bleeding and was vitally stable. On examination we identified 1 cm diameter entry wound at the left lower abdominal wall. The imaging studies showed the bullet in the peritoneal cavity but no injured intraperitoneal and retroperitoneal viscera. We decided to remove the bullet laparoscopically. Twenty-four hours after the intervention the patient was discharged. The decision for managing gunshot patients should be based on clinical and diagnostic findings. Anterior abdominal injuries in a stable patient without other health problems can be managed laparoscopically. PMID:27525150

  9. Laparoscopic Bullet Removal in a Penetrating Abdominal Gunshot.

    PubMed

    Stefanou, Christos; Zikos, Nicolaos; Pappas-Gogos, George; Koulas, Spyridon; Tsimoyiannis, Ioannis

    2016-01-01

    Penetrating abdominal trauma has been traditionally treated by exploratory laparotomy. Nowadays laparoscopy has become an accepted practice in hemodynamically stable patient without signs of peritonitis. We report a case of a lower anterior abdominal gunshot patient treated laparoscopically. A 32-year-old male presented to the Emergency Department with complaint of gunshot penetrating injury at left lower anterior abdominal wall. The patient had no symptoms or obvious bleeding and was vitally stable. On examination we identified 1 cm diameter entry wound at the left lower abdominal wall. The imaging studies showed the bullet in the peritoneal cavity but no injured intraperitoneal and retroperitoneal viscera. We decided to remove the bullet laparoscopically. Twenty-four hours after the intervention the patient was discharged. The decision for managing gunshot patients should be based on clinical and diagnostic findings. Anterior abdominal injuries in a stable patient without other health problems can be managed laparoscopically. PMID:27525150

  10. Identification of rupture locations in patient-specific abdominal aortic aneurysms using experimental and computational techniques.

    PubMed

    Doyle, Barry J; Cloonan, Aidan J; Walsh, Michael T; Vorp, David A; McGloughlin, Timothy M

    2010-05-01

    In the event of abdominal aortic aneurysm (AAA) rupture, the outcome is often death. This paper aims to experimentally identify the rupture locations of in vitro AAA models and validate these rupture sites using finite element analysis (FEA). Silicone rubber AAA models were manufactured using two different materials (Sylgard 160 and Sylgard 170, Dow Corning) and imaged using computed tomography (CT). Experimental models were inflated until rupture with high speed photography used to capture the site of rupture. 3D reconstructions from CT scans and subsequent FEA of these models enabled the wall stress and wall thickness to be determined for each of the geometries. Experimental models ruptured at regions of inflection, not at regions of maximum diameter. Rupture pressures (mean+/-SD) for the Sylgard 160 and Sylgard 170 models were 650.6+/-195.1mmHg and 410.7+/-159.9mmHg, respectively. Computational models accurately predicted the locations of rupture. Peak wall stress for the Sylgard 160 and Sylgard 170 models was 2.15+/-0.26MPa at an internal pressure of 650mmHg and 1.69+/-0.38MPa at an internal pressure of 410mmHg, respectively. Mean wall thickness of all models was 2.19+/-0.40mm, with a mean wall thickness at the location of rupture of 1.85+/-0.33 and 1.71+/-0.29mm for the Sylgard 160 and Sylgard 170 materials, respectively. Rupture occurred at the location of peak stress in 80% (16/20) of cases and at high stress regions but not peak stress in 10% (2/20) of cases. 10% (2/20) of models had defects in the AAA wall which moved the rupture location away from regions of elevated stress. The results presented may further contribute to the understanding of AAA biomechanics and ultimately AAA rupture prediction.

  11. Cardiopulmonary monitoring in intra-abdominal hypertension.

    PubMed

    Malbrain, Manu L N G; Ameloot, Koen; Gillebert, Carl; Cheatham, Michael L

    2011-07-01

    Cardiopulmonary dysfunction and failure are commonly encountered in the patient with intra-abdominal hypertension (IAH) or abdominal compartment syndrome. Accurate assessment and optimization of preload, contractility, and afterload in conjunction with appropriate goal-directed resuscitation and assessment of fluid responsiveness are essential to restore end-organ perfusion. In patients with IAH, the traditional "barometric" preload indicators such as pulmonary artery occlusion pressure and central venous pressure are erroneously increased. Volumetric monitoring techniques have been proven to be superior in directing the appropriate resuscitation together with targeted abdominal perfusion pressure. If such limitations are not recognized, misinterpretation of the patient's cardiac status is likely, resulting in inappropriate and potentially detrimental therapy. IAH also markedly affects the mechanical properties of the chest wall and consequently also the respiratory function. Altered mechanical properties of the chest wall may limit ventilation, influence the work of breathing, affect the interaction between the respiratory muscles, hasten the development of respiratory failure, and interfere with gas exchange. Pulmonary monitoring is important to understand the relationships between intra-abdominal pressure and chest wall mechanics and the impact of IAH on ventilator-induced lung injury, lung distention, recruitment, and lung edema. PMID:21944448

  12. The effect of age on the distensibility of the abdominal aorta of man.

    PubMed

    Newman, D L; Lallemand, R C

    1978-08-01

    The variation with age in distensibility and the dimensions of the abdominal aorta at the bifurcation have been measured in 43 fresh human cadavers. The age range was from birth to 69 years, both sexes being represented. Patients with vascular disease were excluded. Barium sulfate infused into the aorta through an iliac artery enabled the change in diameter to be measured from a roentgenogram with change in pressure. Incremental strain value could thus be calculated. Strain value increased from 0.02 at birth to a maximum at the end of the first decade of life and then decreased to less than 0.01 by the age of 70 years. Aortas in the age group of four to 11 years showed less stiffness with increasing pressure than at other ages. Variations of strain with age correlate with alterations in the ratio of aortic wall collagen to elastin in the young. An increase in the thickness of the wall and an atheroma, in response to prolonged hemodynamic stress, account for increased stiffness in the older age groups. Other age and disease factors may play a part, but further work is required in man to examine the role of relative wall thickness, elastic modulus and alteration in wall structure in determining the variation of aortic distensibility with age reported herein.

  13. Longitudinal displacement of the carotid wall and cardiovascular risk factors: associations with aging, adiposity, blood pressure and periodontal disease independent of cross-sectional distensibility and intima-media thickness.

    PubMed

    Zahnd, Guillaume; Vray, Didier; Sérusclat, André; Alibay, Djhianne; Bartold, Mark; Brown, Alex; Durand, Marion; Jamieson, Lisa M; Kapellas, Kostas; Maple-Brown, Louise J; O'Dea, Kerin; Moulin, Philippe; Celermajer, David S; Skilton, Michael R

    2012-10-01

    The recently discovered longitudinal displacement of the common carotid arterial wall (i.e., the motion along the same plane as the blood flow), may be associated with incident cardiovascular events and represents a novel and relevant clinical information. At present, there have only been a few studies that have been conducted to investigate this longitudinal movement. We propose here a method to assess noninvasively the wall bi-dimensional (two-dimensional [2-D], cross-sectional and longitudinal) motion and present an original approach that combines a robust speckle tracking scheme to guidance by minimal path contours segmentation. Our method is well suited to large clinical population studies as it does not necessitate strong imaging prerequisites. The aim of this study is to describe the association between the longitudinal displacement of the carotid arterial wall and cardiovascular risk factors, among which periodontal disease. Some 126 Indigenous Australians with periodontal disease, an emerging risk factor, and 27 healthy age- and sex-matched non-indigenous control subjects had high-resolution ultrasound scans of the common carotid artery. Carotid intima-media thickness and arterial wall 2-D motion were then assessed using our method in ultrasound B-mode sequences. Carotid longitudinal displacement was markedly lower in the periodontal disease group than the control group (geometric mean (IQR): 0.15 mm (0.13) vs. 0.42 mm (0.30), respectively; p < 0.0001), independent of cardiovascular risk factors, cross-sectional distensibility and carotid intima-media thickness (p < 0.0001). A multivariable model indicated that the strongest correlates of carotid longitudinal displacement in adults with periodontal disease were age (β-coefficient = -.235, p = .03), waist (β-coefficient = -.357, p = 0.001), and pulse pressure (β-coefficient = .175, p = 0.07), independent of other cardiovascular risk factors, cross-sectional distensibility and pulse wave velocity. Carotid

  14. [Treatment of thoracic and abdominal cavity perforation complicated by Henoch-Schonlein purpura nephritis in a patient with high-voltage electric burn].

    PubMed

    Zhang, Wei; Xie, Wei-guo; Min, Wei-xiong; Wang, De-yun; Zhang, Jia; Wan, Shi-yong

    2013-10-01

    A 55-year-old male patient suffered from severe high-voltage electric burn with an area of 20%TBSA full-thickness injury. The injury involved the distal end of left upper limb, right trunk, and whole abdominal wall. Fracture of the 7th-10th ribs was found in the right side of chest, with perforation of abdominal cavity, and bilateral pleural effusion was found. Part of the small intestine was necrotic and exposed. At the early stage, xeno-acellular dermal matrix was grafted after debridement of abdominal wound; peritoneal lavage was performed; negative pressure drainage was performed in orificium fistula of intestine for promoting the adhesion between perforated intestine and abdominal scar. Two orificium fistulas formed after closure of abdominal granulation wound by autologous skin grafting. Eschar of chest wall and denatured ribs were retained. The risk of infection of thoracic cavity was decreased by promoting the adhesion between lung tissue and chest wall. During the treatment, the patient was diagnosed with Henoch-Schonlein purpura nephritis by renal biopsy, with the symptoms of purpura in the lower limbs, heavy proteinuria, severe hypoalbuminemia, edema, etc. After control of kidney damage by immunosuppressive treatment instead of glucocorticoid, alleviation of the levels of proteinuria and blood albumin, free latissimus dorsi myocutaneous flap was excised to repair chest wall, and free skin graft was excised to repair intestinal fistula. After all the wounds were successfully covered, the patient was treated with glucocorticoid combined with immunosuppressants for more than 1 year. The patient was followed up for 3 years, and his renal function was completely recovered with satisfactory clinical outcome.

  15. Abdominal aortic aneurysm.

    PubMed

    Keisler, Brian; Carter, Chuck

    2015-04-15

    Abdominal aortic aneurysm refers to abdominal aortic dilation of 3.0 cm or greater. The main risk factors are age older than 65 years, male sex, and smoking history. Other risk factors include a family history of abdominal aortic aneurysm, coronary artery disease, hypertension, peripheral artery disease, and previous myocardial infarction. Diagnosis may be made by physical examination, an incidental finding on imaging, or ultrasonography. The U.S. Preventive Services Task Force released updated recommendations for abdominal aortic aneurysm screening in 2014. Men 65 to 75 years of age with a history of smoking should undergo one-time screening with ultrasonography based on evidence that screening will improve abdominal aortic aneurysm-related mortality in this population. Men in this age group without a history of smoking may benefit if they have other risk factors (e.g., family history of abdominal aortic aneurysm, other vascular aneurysms, coronary artery disease). There is inconclusive evidence to recommend screening for abdominal aortic aneurysm in women 65 to 75 years of age with a smoking history. Women without a smoking history should not undergo screening because the harms likely outweigh the benefits. Persons who have a stable abdominal aortic aneurysm should undergo regular surveillance or operative intervention depending on aneurysm size. Surgical intervention by open or endovascular repair is the primary option and is typically reserved for aneurysms 5.5 cm in diameter or greater. There are limited options for medical treatment beyond risk factor modification. Ruptured abdominal aortic aneurysm is a medical emergency presenting with hypotension, shooting abdominal or back pain, and a pulsatile abdominal mass. It is associated with high prehospitalization mortality. Emergent surgical intervention is indicated for a rupture but has a high operative mortality rate. PMID:25884861

  16. 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.

  17. [Abdominal compartment syndrome].

    PubMed

    Pottecher, T; Segura, P; Launoy, A

    2001-04-01

    French physicians dealing with abdominal emergencies are not very familiar with the abdominal compartment syndrome (ACS). Increased abdominal pressure has deleterious consequences on local (intestine, liver, kidney) circulation, leading to death in the absence of correct treatment. Abdominal trauma and ruptured aortic aneurism are the main causes of ACS. Clinical presentation may be misleading: respiratory failure, oliguria or circulatory symptoms are often predominant. Abdominal palpation is inefficient for evaluating intra-abdominal pressure (IAP); only measurement of cystic pressure allows precise evaluation of IAP. Abdominal decompression is the treatment of choice. It must be performed as soon as IAP exceeds 25 mmHg. The procedure may be risky with a high incidence of severe complications when ischaemic territories are reperfused. Recent data underline the importance of compensation of hypovolemia before decompression. Abdominal closure may necessitate various techniques (aponevrotomy, Bogota bags, etc.). At any rate, IAP must remain low at the end of the procedure. In case of suspicion of ACS, early measurement of IAP is mandatory. If pressure is over 25 mmHg, a decompressive procedure must be initiated. PMID:11340703

  18. [Semeiotics of abdominal tuberculosis].

    PubMed

    Guseĭnov, G K; Ramazanova, A M; Guseĭnov, A G

    1984-01-01

    Examination of 119 patients with abdominal tuberculosis permitted the description of the characteristic semiotics of the illness. Today the patients with abdominal tuberculosis are mainly women of child-bearing age with a long-term tuberculosis catamnesis and intoxication, with a history of tuberculosis of different sites, those suffering from tuberculosis or its sequels at present (64%), those with pains (94%), discomfort or swelling of the abdomen (79%), malfunction of the gastrointestinal tract (65%), weight loss (86%), malnutrition (72%), anemia (63%), not infrequently with inflammatory induration (43%) or ascites in the abdominal cavity (39%). In addition to this characteristic semiotics, the patients with abdominal tuberculosis may demonstrate the most different and unexpected symptoms up to acute abdomen (23%). To make differential diagnosis of abdominal tuberculosis, one has often to resort to diagnostic laparotomy, laparoscopy, Koch's test and to trial therapy.

  19. 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

  20. 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.

  1. [What do general, abdominal and vascular surgeons need to know on plastic surgery - aspects of plastic surgery in the field of general, abdominal and vascular surgery].

    PubMed

    Damert, H G; Altmann, S; Stübs, P; Infanger, M; Meyer, F

    2015-02-01

    There is overlap between general, abdominal and vascular surgery on one hand and plastic surgery on the other hand, e.g., in hernia surgery, in particular, recurrent hernia, reconstruction of the abdominal wall or defect closure after abdominal or vascular surgery. Bariatric operations involve both special fields too. Plastic surgeons sometimes use skin and muscle compartments of the abdominal wall for reconstruction at other regions of the body. This article aims to i) give an overview about functional, anatomic and clinical aspects as well as the potential of surgical interventions in plastic surgery. General/abdominal/vascular surgeons can benefit from this in their surgical planning and competent execution of their own surgical interventions with limited morbidity/lethality and an optimal, in particular, functional as well as aesthetic outcome, ii) support the interdisciplinary work of general/abdominal/vascular and plastic surgery, and iii) provide a better understanding of plastic surgery and its profile of surgical interventions and options.

  2. Ultrasound evaluation of abdominal masses in Ethiopian child patients.

    PubMed

    Kebede, Assefa Getachew; Nigussie, Yared

    2011-07-01

    The aim of this study was to assess the pattern of abdominal masses and evaluate the value of ultrasound in paediatric abdominal masses. We used a cross-sectional study of abdominal masses in children attending a university teaching hospital. The common abdominal masses were: Wilms' tumour, 12 (14.8%); lymphoma, 11 (13.6%); appendiceal mass/abscess, 11 (13.6%); neuroblastoma, 7 (8.6%); TB, 6 (7.4%); hydronephrosis, 5 (6.2%); abdominal wall abscess, 6 (7.4%); hydatidcyst, 4 (4.9%); mesenteric cyst, 3 (3.7%); and intussusceptions, 3 (3.7%). Identification of a purely cystic mass was suggestive of benign lesion (odds ratio [OR] = 118, P = 0.0001) and masses found in the <5 years age group tend to be malignant (OR = 2.77). The most common sites of origin were kidneys, retroperitoneal extra renal and gastrointestinal tract. The overall diagnostic accuracy of ultrasound was 88.9%.

  3. 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 ...

  4. Thick-walled carbon composite multifunctional structures

    NASA Astrophysics Data System (ADS)

    Haake, John M.; Jacobs, Jack H.; McIlroy, Bruce E.

    1997-06-01

    Satellite programs are moving in the direction of smaller and lighter structures. Technological advances have permitted more sophisticated equipment to be consolidated into compact spaces. Micro-satellites, between 10 and 100 kg, will incorporate micro-electric devices into the lay-up of the satellite structure. These structures will be designed to carry load, provide thermal control, enhance damping, and include integrated passive electronics. These multifunctional structures offer lighter weight, reduced volume, and a 'smarter' overall package for incorporation of sensors, electronics, fiber optics, powered appendages or active components. McDonnell Douglas Corporation (MDC) has applied technology from the synthesis and processing of intelligent cost effective structures (SPICES) and independent research and development (IRAD) programs to the modular instrument support system (MISS) for multifunctional space structures and micro-satellites. The SPICES program was funded by the Defense Advanced Research Projects Agency (DARPA) to develop affordable manufacturing processes for smart materials to be used in vibration control, and the MISS program was funded by NASA-Langley. The MISS program was conceived to develop concepts and techniques to make connections between different multifunctional structures. MDA fabricated a trapezoidal carbon composite structure out of IM7/977-3 tape prepreg. Flex circuits, thermal and optical conduits were embedded to realize a utility modular connector. These provide electrical, thermal, optical and mechanical connections between micro- satellite components. A quick disconnect mount was also developed to accommodate a variety of devices such as solar arrays, power sources, thermal transfer and vibration control modules.

  5. Abdominal emergencies in pediatrics.

    PubMed

    Coca Robinot, D; Liébana de Rojas, C; Aguirre Pascual, E

    2016-05-01

    Abdominal symptoms are among the most common reasons for pediatric emergency department visits, and abdominal pain is the most frequently reported symptom. Thorough history taking and physical examination can often reach the correct diagnosis. Knowing the abdominal conditions that are most common in each age group can help radiologists narrow the differential diagnosis. When imaging tests are indicated, ultrasonography is usually the first-line technique, enabling the diagnosis or adding relevant information with the well-known advantages of this technique. Nowadays, plain-film X-ray studies are reserved for cases in which perforation, bowel obstruction, or foreign body ingestion is suspected. It is also important to remember that abdominal pain can also occur secondary to basal pneumonia. CT is reserved for specific indications and in individual cases, for example, in patients with high clinical suspicion of abdominal disease and inconclusive findings at ultrasonography. We review some of the most common conditions in pediatric emergencies, the different imaging tests indicated in each case, and the imaging signs in each condition.

  6. 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.

  7. An investigation of the reproducibility of ultrasound measures of abdominal muscle activation in patients with chronic non-specific low back pain

    PubMed Central

    Maher, Chris G.; Latimer, Jane; Hodges, Paul W.; Shirley, Debra

    2009-01-01

    Ultrasound (US) measures are used by clinicians and researchers to evaluate improvements in activity of the abdominal muscles in patients with low back pain. Studies evaluating the reproducibility of these US measures provide some information; however, little is known about the reproducibility of these US measures over time in patients with low back pain. The objectives of this study were to estimate the reproducibility of ultrasound measurements of automatic activation of the lateral abdominal wall muscles using a leg force task in patients with chronic low back pain. Thirty-five participants from an existing randomised, blinded, placebo-controlled trial participated in the study. A reproducibility analysis was undertaken from all patients using data collected at baseline and after treatment. The reproducibility of measurements of thickness, muscle activation (thickness changes) and muscle improvement/deterioration after intervention (differences in thickness changes from single images made before and after treatment) was analysed. The reproducibility of static images (thickness) was excellent (ICC2,1 = 0.97, 95% CI = 0.96–0.97, standard error of the measurement (SEM) = 0.04 cm, smallest detectable change (SDC) = 0.11 cm), the reproducibility of thickness changes was moderate (ICC2,1 = 0.72, 95% CI 0.65–0.76, SEM = 15%, SDC 41%), while the reproducibility of differences in thickness changes from single images with statistical adjustment for duplicate measures was poor (ICC2,1 = 0.44, 95% CI 0.33–0.58, SEM = 21%, SDC = 66.5%). Improvements in the testing protocol must be performed in order to enhance reproducibility of US as an outcome measure for abdominal muscle activation. PMID:19415347

  8. Abdominal Compartment Syndrome Secondary to Chronic Constipation

    PubMed Central

    Flageole, Helene; Ouahed, Jodie; Walton, J. Mark; Yousef, Yasmin

    2011-01-01

    Abdominal compartment syndrome (ACS) is defined as an elevated intraabdominal pressure with evidence of organ dysfunction. The majority of published reports of ACS are in neonates with abdominal wall defects and in adults following trauma or burns, but it is poorly described in children. We describe the unusual presentation of an 11-year-old boy with a long history of chronic constipation who developed acute ACS requiring resuscitative measures and emergent disimpaction. He presented with a 2-week history of increasing abdominal pain, nausea, diminished appetite and longstanding encopresis. On exam, he was emaciated with a massively distended abdomen with a palpable fecaloma. Abdominal XR confirmed these findings. Within 24 hours of presentation, he became tachycardic and oliguric with orthostatic hypotension. Following two enemas, he acutely deteriorated with severe hypotension, marked tachycardia, acute respiratory distress, and a declining mental status. Endotracheal intubation, fluid boluses, and vasopressors were commenced, followed by emergent surgical fecal disimpaction. This resulted in rapid improvement in vital signs. He has been thoroughly investigated and no other condition apart from functional constipation has been identified. Although ACS secondary to constipation is extremely unusual, this case illustrates the need to actively treat constipation and what can happen if it is not. PMID:22606517

  9. [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.

  10. The Acute Abdominal Aorta.

    PubMed

    Mellnick, Vincent M; Heiken, Jay P

    2015-11-01

    Acute disorders of the abdominal aorta are potentially lethal conditions that require prompt evaluation and treatment. Computed tomography (CT) is the primary imaging method for evaluating these conditions because of its availability and speed. Volumetric CT acquisition with multiplanar reconstruction and three-dimensional analysis is now the standard technique for evaluating the aorta. MR imaging may be useful for select applications in stable patients in whom rupture has been excluded. Imaging is indispensable for diagnosis and treatment planning, because management has shifted toward endoluminal repair. Acute abdominal aortic conditions most commonly are complications of aneurysms and atherosclerosis. PMID:26526434

  11. Evaluation of Clinical Outcomes after Abdominal Rectopexy and Delorme’s Procedure for Rectal Prolapse: A Prospective Study

    PubMed Central

    Makineni, Hemanth; Rai, B.K. Shivprasad

    2014-01-01

    Background: Complete rectal prolapse is characterized by protrusion of full thickness rectal wall through the anal orifice. Despite its rarity more than 100 surgical procedures have been described and there are no good evidence based recommendations for selection of a surgical procedure. This study was conducted to evaluate the clinical outcomes of commonly used procedures for rectal prolapse at our hospital. Materials and Methods: Twenty seven patients presenting with complete rectal prolapse between May 2011 to May 2013 were included in this prospective study. Patients underwent either Abdominal rectopexy or Delorme’s procedure after evaluation, based on clinical judgment of experienced surgeons. Patient characteristics, complications, post-operative length of hospitalization and clinical outcomes were assessed. Patients were followed up for a mean duration of 14 months. Results: Seventeen patients underwent Abdominal rectopexy (Posterior mesh rectopexy), ten patients underwent Delorme’s procedure. No postoperative mortalities or major complications were noted. Post operative morbidity (minor) was 17% in Abdominal rectopexy group and 10% in Delormes group 0%. Incontinence improved in all six patients (100%) in rectopexy group, four patients (80%) in Delorme’s procedure group. Two patients (11%) in rectopexy group reported increase in constipation post operatively. There was one recurrence in Delorme’s procedure group with no recurrences in Abdominal rectopexy group. Conclusion: The treatment of rectal prolapse should be individualized to achieve best results. Abdominal rectopexy can be safely applied in most of patients with minimal post operative increase in constipation and recurrence by using posterior mesh rectopexy technique. Delorme’s procedure can be performed with minimal morbidity and shorter hospital stay and good functional results with acceptable recurrence rate. Delorme’s can be considered as an alternative to rectopexy not only in

  12. 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

  13. Predictive factors of abdominal compartment syndrome in neonatal age.

    PubMed

    Schierz, Ingrid Anne Mandy; Giuffrè, Mario; Piro, Ettore; Ortolano, Rita; Siracusa, Fortunato; Pinello, Giuseppa; La Placa, Simona; Corsello, Giovanni

    2014-01-01

    In the pediatric population, abdominal compartment syndrome (ACS) is a known complication of abdominal wall defect repair. However, there are only few reports on ACS in newborns and only a proposal of critical intra-abdominal pressure value (IAP) in term newborns, absent in preterm newborns. Although the prevalent clinical sign is tense abdominal distension, it may be difficult to distinguish ACS from pathologies that will not require decompression. The purpose of this study was to identify predictors for ACS and therefore morbidity or mortality indicators. We reviewed newborns presenting with tense abdominal distension and end organ failure. Anamnestic, clinical, laboratory, and instrumental investigations were analyzed to extrapolate predictors. Outcomes were compared with a control group. The incidence of ACS in our neonatal intensive care unit was 5% in the overall population of babies, 16% in tracheal-ventilated newborns, and 57% in infants with abdominal wall defects. We found that, with onset of acidosis or high gastric residuals, the lactate values will be predictive for mortality. We can also suggest paying particular attention to high lactate values just at the onset of distension, in infants with more advanced gestational age, with previously surgical repair, to determine early surgical intervention independently of a specific IAP measurement.

  14. Precise measurement of micro bubble resonator thickness by internal aerostatic pressure sensing.

    PubMed

    Lu, Qijing; Liao, Jie; Liu, Sheng; Wu, Xiang; Liu, Liying; Xu, Lei

    2016-09-01

    We develop a new, simple and non-destructive method to precisely measure the thickness of thin wall micro bubble resonators (MBRs) by using internal aerostatic pressure sensing. Measurement error of 1% at a bubble wall thickness of 2 μm is achieved. This method is applicable to both thin wall and thick wall MBR with high measurement accuracy. PMID:27607689

  15. Precise measurement of micro bubble resonator thickness by internal aerostatic pressure sensing.

    PubMed

    Lu, Qijing; Liao, Jie; Liu, Sheng; Wu, Xiang; Liu, Liying; Xu, Lei

    2016-09-01

    We develop a new, simple and non-destructive method to precisely measure the thickness of thin wall micro bubble resonators (MBRs) by using internal aerostatic pressure sensing. Measurement error of 1% at a bubble wall thickness of 2 μm is achieved. This method is applicable to both thin wall and thick wall MBR with high measurement accuracy.

  16. Anti-TNF-Alpha-Adalimumab Therapy Is Associated with Persistent Improvement of Endothelial Function without Progression of Carotid Intima-Media Wall Thickness in Patients with Rheumatoid Arthritis Refractory to Conventional Therapy

    PubMed Central

    Gonzalez-Juanatey, Carlos; Vazquez-Rodriguez, Tomas R.; Miranda-Filloy, Jose A.; Gomez-Acebo, Ines; Testa, Ana; Garcia-Porrua, Carlos; Sanchez-Andrade, Amalia; Llorca, Javier; González-Gay, Miguel A.

    2012-01-01

    To determine whether treatment with the anti-TNF-alpha blocker adalimumab yields persistent improvement of endothelial function and prevents from morphological progression of subclinical atherosclerosis in patients with rheumatoid arthritis (RA) refractory to conventional therapy, a series of 34 consecutive RA patients, attending hospital outpatient clinics and who were switched from disease modifying antirheumatic drug therapy to anti-TNF-alpha-adalimumab treatment because of severe disease, were assessed by ultrasonography techniques before the onset of adalimumab therapy (at day 0) and then at day 14 and at month 12. Values of flow-mediated endothelium-dependent vasodilatation at day 14 and at month 12 were significantly higher (mean ± standard deviation (SD): 6.1 ± 3.9%; median: 5.7% at day 14, and mean ± SD: 7.4 ± 2.8%; median: 6.9% at month 12) than those obtained at day 0 (mean: 4.5 ± 4.0%; median: 3.6%; P = 0.03 and P < 0.001, resp.). Endothelium-independent vasodilatation results did not significantly change compared with those obtained at day 0. No significant differences were observed when carotid artery intima-media wall thickness values obtained at month 12 (mean ± SD: 0.69 ± 0.21 mm) were compared with those found at day 0 (0.65 ± 0.16 mm) (P = 0.3). In conclusion, anti-TNF-alpha-adalimumab therapy has beneficial effects on the development of the subclinical atherosclerosis disease in RA. PMID:22899879

  17. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) ... final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final recommendation statement applies to adults ages ...

  18. Abdominal Pain, Long-Term

    MedlinePlus

    MENU Return to Web version Abdominal Pain, Long-term See complete list of charts. Ongoing or recurrent abdominal pain, also called chronic pain, may be difficult to diagnose, causing frustration for ...

  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. Mouse bladder wall injection.

    PubMed

    Fu, Chi-Ling; Apelo, Charity A; Torres, Baldemar; Thai, Kim H; Hsieh, Michael H

    2011-07-12

    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.

  1. 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.

  2. Abdominal SPECT imaging

    SciTech Connect

    Van Heertum, R.L.; Brunetti, J.C.; Yudd, A.P.

    1987-07-01

    Over the past several years, abdominal single photon emission computed tomography (SPECT) imaging has evolved from a research tool to an important clinical imaging modality that is helpful in the diagnostic assessment of a wide variety of disorders involving the abdominal viscera. Although liver-spleen imaging is the most popular of the abdominal SPECT procedures, blood pool imaging is becoming much more widely utilized for the evaluation of cavernous hemangiomas of the liver as well as other vascular abnormalities in the abdomen. Adjunctive indium leukocyte and gallium SPECT studies are also proving to be of value in the assessment of a variety of infectious and neoplastic diseases. As more experience is acquired in this area, SPECT should become the primary imaging modality for both gallium and indium white blood cells in many institutions. Renal SPECT, on the other hand, has only recently been used as a clinical imaging modality for the assessment of such parameters as renal depth and volume. The exact role of renal SPECT as a clinical tool is, therefore, yet to be determined. 79 references.

  3. Abdominal emergencies during pregnancy.

    PubMed

    Bouyou, J; Gaujoux, S; Marcellin, L; Leconte, M; Goffinet, F; Chapron, C; Dousset, B

    2015-12-01

    Abdominal emergencies during pregnancy (excluding obstetrical emergencies) occur in one out of 500-700 pregnancies and may involve gastrointestinal, gynecologic, urologic, vascular and traumatic etiologies; surgery is necessary in 0.2-2% of cases. Since these emergencies are relatively rare, patients should be referred to specialized centers where surgical, obstetrical and neonatal cares are available, particularly because surgical intervention increases the risk of premature labor. Clinical presentations may be atypical and misleading because of pregnancy-associated anatomical and physiologic alterations, which often result in diagnostic uncertainty and therapeutic delay with increased risks of maternal and infant morbidity. The most common abdominal emergencies are acute appendicitis (best treated by laparoscopic appendectomy), acute calculous cholecystitis (best treated by laparoscopic cholecystectomy from the first trimester through the early part of the third trimester) and intestinal obstruction (where medical treatment is the first-line approach, just as in the non-pregnant patient). Acute pancreatitis is rare, usually resulting from trans-ampullary passage of gallstones; it usually resolves with medical treatment but an elevated risk of recurrent episodes justifies laparoscopic cholecystectomy in the 2nd trimester and endoscopic sphincterotomy in the 3rd trimester. The aim of the present work is to review pregnancy-induced anatomical and physiological modifications, to describe the main abdominal emergencies during pregnancy, their specific features and their diagnostic and therapeutic management.

  4. [Value and sensitivity of abdominal ultrasound in preoperative histologic diagnosis before laparoscopic cholecystectomy].

    PubMed

    Hoffmann, C; Trebing, G; Meyer, L; Scheele, J

    1998-01-01

    In a retrospective study we compared the findings of our abdominal ultra-sound diagnostic of the gallbladder and the common bile duct with the results ot preoperative ERCP, intraoperative findings and the histological results. The test parameters were the size of the gallbladder, the number and the size of biliary calculi, the thickness and the constitution of the wall of the gallbladder and the consecutive grade of inflammation, the wideness of the common bile duct and the suspicion of a choledocholithiasis, respectively. In acute cholecystitis we performed laparoscopic cholecystectomy within 24 hours, in symtomatic cholecystolithiasis without cholecystitis an elective laparoscopic cholecystectomy. If there was suspicion of a choledocholithiasis we performed a preoperative ERCP. Altogether we had correct findings of the common bile duct in our ultrasound diagnostic in 133 of 136 cases (97.8%), only in 3 of 136 cases (2.2%) we had false negative ultrasound findings. With a generous indication to ERCP caused by anamnestic and/or laboratory findings the obstruction of the bile duct could be diagnosted and eliminated in 2 of these 3 cases preoperatively. In all cases of bile duct dilatation (7 mm and more) we found an obstruction of the common bile duct. Our results demonstrate that abdominal ultrasound is a high-efficiency method in the preoperative diagnostic of gallbladder and common bile duct stones.

  5. 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.

  6. Infected abdominal aortic aneurysm due to Morganella morganii: CT findings.

    PubMed

    Kwon, Oh Young; Lee, Jong Seok; Choi, Han Sung; Hong, Hoon Pyo; Ko, Young Gwan

    2011-02-01

    An infected aortic aneurysm, or mycotic aneurysm, is a rare arterial dilatation due to destruction of the infected vessel wall. Common pathogens resulting in an infected aortic aneurysm are Salmonella and Clostridium species, as well as Staphylococcus aureus; Morganella morganii, on the other hand, is very rare. An infected abdominal aortic aneurysm has tendencies to grow rapidly and to rupture. The mortality rate is high in patients undergoing emergent surgical intervention. We report the case of a 65-year-old man who presented with an infected abdominal aortic aneurysm caused by M. morganii. A high index of suspicion and imaging tests are necessary in order to diagnose an infected aortic aneurysm.

  7. Ultrasound in the diagnosis of palpable abdominal masses in children.

    PubMed

    Annuar, Z; Sakijan, A S; Annuar, N; Kooi, G H

    1990-12-01

    Ultrasound examinations were done to evaluate clinically palpable abdominal masses in 125 children. The examinations were normal in 21 patients. In 15 patients, the clinically palpable masses were actually anterior abdominal wall abscesses or hematomas. Final diagnosis was available in 87 of 89 patients with intraabdominal masses detected on ultrasound. The majority (71%) were retroperitoneal masses where two-thirds were of renal origin. Ultrasound diagnosis was correct in 68 patients (78%). All cases of hydronephrosis were correctly diagnosed based on characteristic ultrasound appearances. Correct diagnoses of all cases of adrenal hematoma, psoas abscess, liver hematoma, liver abscess and one case of liver metastases were achieved with correlation of relevant clinical information.

  8. Leaking mycotic abdominal aortic aneurysm.

    PubMed

    Sing, T M; Young, N; O'Rourke, I C; Tomlinson, P

    1994-11-01

    A case of leaking mycotic abdominal aortic aneurysm is reported, with a brief review of the literature. A 58 year old female presented with shoulder and abdominal pain associated with diarrhoea, vomiting and fever with leucocytosis. Computed tomography of the abdomen showed pooling of contrast in the retroperitoneum anterior to a non-dilated abdominal aorta. There was considerable retroperitoneal blood accumulating in a mass-like lesion in the right lower abdomen and pelvis obstructing the right renal collecting system. Laparotomy revealed a 4 cm diameter saccular aneurysm of the abdominal aorta, with a 1 cm diameter neck. Culture of the thrombus grew Streptococcus pyogenes. PMID:7993259

  9. Hypnosis for functional abdominal pain.

    PubMed

    Gottsegen, David

    2011-07-01

    Chronic abdominal pain is a common pediatric condition affecting 20% of the pediatric population worldwide. Most children with this disorder are found to have no specific organic etiology and are given the diagnosis of functional abdominal pain. Well-designed clinical trials have found hypnotherapy and guided imagery to be the most efficacious treatments for this condition. Hypnotic techniques used for other somatic symptoms are easily adaptable for use with functional abdominal pain. The author discusses 2 contrasting hypnotic approaches to functional abdominal pain and provides implications for further research. These approaches may provide new insights into this common and complex disorder. PMID:21922712

  10. 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.

  11. 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)

  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. Role of tissue expanders in patients with loss of abdominal domain awaiting intestinal transplantation.

    PubMed

    Watson, Melissa J; Kundu, Neilendu; Coppa, Christopher; Djohan, Risal; Hashimoto, Koji; Eghtesad, Bijan; Fujiki, Masato; Diago Uso, Teresa; Gandhi, Namita; Nassar, Ahmed; Abu-Elmagd, Kareem; Quintini, Cristiano

    2013-12-01

    Abdominal closure is a complex surgical problem in intestinal transplant recipients with loss of abdominal domain, as graft exposure results in profound morbidity. Although intraoperative coverage techniques have been described, this is the first report of preoperative abdominal wall augmentation using tissue expanders in patients awaiting intestinal transplantation. We report on five patients who received a total of twelve tissue expanders as a means to increase abdominal surface area. Each patient had a compromised abdominal wall (multiple prior operations, enterocutaneous fistulae, subcutaneous abscesses, stomas) with loss of domain and was identified as high risk for an open abdomen post-transplant. Cross-sectional imaging and dimensional analysis were performed to quantify the effect of the expanders on total abdominal and intraperitoneal cavity volumes. The overall mean increase in total abdominal volume was 958 cm(3) with a mean expander volume of 896.5 cc. Two expanders were removed in the first patient due to infection, but after protocol modification, there were no further infections. Three patients eventually underwent small bowel transplantation with complete graft coverage. In our preliminary experience, abdominal tissue expander placement is a safe, feasible, and well-tolerated method to increase subcutaneous domain and facilitate graft coverage in patients undergoing intestinal transplantation. PMID:24118196

  14. Great Walls.

    ERIC Educational Resources Information Center

    Blackburn, Steve; Moore, Tim

    1996-01-01

    Explains why installing a well-designed indoor climbing wall can draw new users to an athletic facility. Climbing-wall design elements and gear are discussed and a checklist for working with contractors is provided.(GR)

  15. 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.

  16. Penetrating abdominal trauma.

    PubMed

    Henneman, P L

    1989-08-01

    The management of patients with penetrating abdominal trauma is outlined in Figure 1. Patients with hemodynamic instability, evisceration, significant gastrointestinal bleeding, peritoneal signs, gunshot wounds with peritoneal violation, and type 2 and 3 shotgun wounds should undergo emergency laparotomy. The initial ED management of these patients includes airway management, monitoring of cardiac rhythm and vital signs, history, physical examination, and placement of intravenous lines. Blood should be obtained for initial hematocrit, type and cross-matching, electrolytes, and an alcohol level or drug screen as needed. Initial resuscitation should utilize crystalloid fluid replacement. If more than 2 liters of crystalloid are needed to stabilize an adult (less in a child), blood should be given. Group O Rh-negative packed red blood cells should be immediately available for a patient in impending arrest or massive hemorrhage. Type-specific blood should be available within 15 minutes. A patient with penetrating thoracic and high abdominal trauma should receive a portable chest x-ray, and a hemo- or pneumothorax should be treated with tube thoracostomy. An unstable patient with clinical signs consistent with a pneumothorax, however, should receive a tube thoracostomy prior to obtaining roentgenographic confirmation. If time permits, a nasogastric tube and Foley catheter should be placed, and the urine evaluated for blood (these procedures can be performed in the operating room). If kidney involvement is suspected because of hematuria or penetrating trauma in the area of a kidney or ureter in a patient requiring surgery, a single-shot IVP should be performed either in the ED or the operating room. An ECG is important in patients with possible cardiac involvement and in patients over the age of 40 going to the operating room. Tetanus status should be updated, and appropriate antibiotics covering bowel flora should be given. Operative management should rarely be delayed

  17. Solitary fibrous tumors arising in abdominal wall hernia sacs.

    PubMed

    Lee, J R; Hancock, S M; Martindale, R G

    2001-06-01

    Solitary fibrous tumor (SFT) of the peritoneum is an unusual spindle-cell neoplasm. SFT was originally described in the pleura; however it is now diagnosed in multiple extrathoracic sites. Most believe that the tumor is of mesenchymal origin and should be classified as a variant of fibroma. SFT of the pleura and peritoneum have also been called fibrous mesothelioma, and the cell of origin is felt to be a pluripotential submesothelial mesenchymal cell. Primary tumors arising in hernia sacs are rare, and we report on two patients with hernia SFT. The first is a 67-year-old man who had a diffusely thickened distal left inguinal hernia sac. Within the sac was copious myxoid material mimicking pseudomyxoma peritonei. Herniorrhaphy and orchiectomy were performed. The second is a 44-year-old woman with a midepigastric mass attached to a ventral hernia. Wide local excision was performed. Both tumors demonstrated plump spindle cells, one with myxoid background and the other with keloidal collagen. Calretinin immunostaining was positive in both tumors, whereas CD34 was negative. This suggests tumor origin from a submesothial pluripotential cell that maintains potential for mesothelial differentiation. Surgical excision is the treatment of choice with the degree of resectability being a powerful predictor of outcome.

  18. Abdominal aortic feminism.

    PubMed

    Mortimer, Alice Emily

    2014-11-14

    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.

  19. [Radiofrequency ablation of an unresectable abdominal tumor].

    PubMed

    Sézeur, Alain; Fritsch, Sylvie; Louvet, Christophe; Kujas, Albert; Mosnier, Henri; Talbot, Jean-Noël; Grimberg, Sylvie

    2003-02-01

    Remnant malignant tissue is left behind after conventional surgery for an unresectable intraperitoneal malignant tumor. Standard radiotherapy or chemotherapy rarely enables good tumor control. We report the case of a 74-year-old man who developed a local recurrence of a sigmoid tumor located 5 to 6 cm from the anus. The tumor was fixed to the pelvic wall and could not be totally eradicated with conventional surgery. Preoperative peroperative assessment confirmed the absence of metastatic spread. Radiotherapy could not be performed due to risk of bowel injury. Peroperative radiofrequency ablation was followed by surgical colorectal resection without restoration of intestinal continuity, leaving only tumor tissue destroyed by radiofrequency. No adjuvant treatment was proposed because of intolerance to chemotherapy. Clinical assessment and thoracic and abdominal CT scan confirmed the absence of recurrence 26 months after radiofrequency ablation. Serum markers remained normal.

  20. 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.