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Sample records for crystal vein locator

  1. 21 CFR 880.6970 - Liquid crystal vein locator.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Miscellaneous... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  2. Finger vein recognition based on finger crease location

    Science.gov (United States)

    Lu, Zhiying; Ding, Shumeng; Yin, Jing

    2016-07-01

    Finger vein recognition technology has significant advantages over other methods in terms of accuracy, uniqueness, and stability, and it has wide promising applications in the field of biometric recognition. We propose using finger creases to locate and extract an object region. Then we use linear fitting to overcome the problem of finger rotation in the plane. The method of modular adaptive histogram equalization (MAHE) is presented to enhance image contrast and reduce computational cost. To extract the finger vein features, we use a fusion method, which can obtain clear and distinguishable vein patterns under different conditions. We used the Hausdorff average distance algorithm to examine the recognition performance of the system. The experimental results demonstrate that MAHE can better balance the recognition accuracy and the expenditure of time compared with three other methods. Our resulting equal error rate throughout the total procedure was 3.268% in a database of 153 finger vein images.

  3. Theoretical prediction of gold vein location in deposits originated by a wall magma intrusion

    Science.gov (United States)

    Martin, Pablo; Maass-Artigas, Fernando; Cortés-Vega, Luis

    2016-05-01

    The isotherm time-evolution resulting from the intrusion of a hot dike in a cold rock is analized considering the general case of nonvertical walls. This is applied to the theoretical prediction of the gold veins location due to isothermal evolution. As in previous treatments earth surface effects are considered and the gold veins are determined by the envelope of the isotherms. The locations of the gold veins in the Callao mines of Venezuela are now well predicted. The new treatment is now more elaborated and complex that in the case of vertical walls, performed in previous papers, but it is more adequated to the real cases as the one in El Callao, where the wall is not vertical.

  4. Modal dynamics in hollow-core photonic-crystal fibers with elliptical veins.

    Science.gov (United States)

    Hochman, Amit; Leviatan, Yehuda

    2005-08-08

    Modal characteristics of hollow-core photonic-crystal fibers with elliptical veins are studied by use of a recently proposed numerical method. The dynamic behavior of bandgap guided modes, as the wavelength and aspect ratio are varied, is shown to include zero-crossings of the birefringence, polarization dependent radiation losses, and deformation of the fundamental mode.

  5. Locating and Visualizing Crystals for X-Ray Diffraction Experiments.

    Science.gov (United States)

    Becker, Michael; Kissick, David J; Ogata, Craig M

    2017-01-01

    Macromolecular crystallography has advanced from using macroscopic crystals, which might be >1 mm on a side, to crystals that are essentially invisible to the naked eye, or even under a standard laboratory microscope. As crystallography requires recognizing crystals when they are produced, and then placing them in an X-ray, electron, or neutron beam, this provides challenges, particularly in the case of advanced X-ray sources, where beams have very small cross sections and crystals may be vanishingly small. Methods for visualizing crystals are reviewed here, and examples of different types of cases are presented, including: standard crystals, crystals grown in mesophase, in situ crystallography, and crystals grown for X-ray Free Electron Laser or Micro Electron Diffraction experiments. As most techniques have limitations, it is desirable to have a range of complementary techniques available to identify and locate crystals. Ideally, a given technique should not cause sample damage, but sometimes it is necessary to use techniques where damage can only be minimized. For extreme circumstances, the act of probing location may be coincident with collecting X-ray diffraction data. Future challenges and directions are also discussed.

  6. Location control of crystal grains in excimer laser crystallization of silicon thin films

    Science.gov (United States)

    Kumomi, Hideya

    2003-07-01

    Location of crystal grains in polycrystalline Si thin films formed by excimer-laser crystallization is controlled by manipulating the superlateral-growth phenomenon. The superlateral growth of a single grain occurs preferentially at an artificial site where nanometer-sized crystallites are embedded in the precursory amorphous thin films. Only a part of the crystallites embedded in the site could survive the melting and grow to serve as the seed crystal in the subsequent recrystallization. Such grain-location control provides a basis for two-dimensional control of the grain-boundary location in low-temperature polycrystalline Si thin films, which is essential to the device-to-device uniformity of high-performance thin-film transistors.

  7. Contact force and impedance decrease during ablation depends on catheter location and orientation: insights from pulmonary vein isolation using a contact force-sensing catheter.

    Science.gov (United States)

    Knecht, Sven; Reichlin, Tobias; Pavlovic, Nikola; Schaer, Beat; Osswald, Stefan; Sticherling, Christian; Kühne, Michael

    2015-09-01

    Contact force (CF) sensing during radiofrequency (RF) ablation allows controlling lesion size. The aim of this study was to analyze the impact of catheter tip location and orientation on the association of CF and impedance decrease. We retrospectively analyzed RF applications from 32 patients undergoing catheter ablation for paroxysmal atrial fibrillation using a force-sensing catheter and 3D mapping system. CF, catheter location and orientation relative to the tissue during ablation as well as the absolute impedance decrease during the first 20 s of ablation as a surrogate for lesion effectiveness were analyzed for 791 RF applications. While a higher CF was achieved around the right pulmonary veins (12.5 vs. 11.4 g, p = 0.045), a lower median absolute impedance decrease within the first 20 s was seen around the right veins compared to the left veins (9.3 vs. 10.2 Ω, p = 0.02). With different catheter orientations relative to the tissue, higher CF and impedance decrease was seen when the catheter was orientated parallel or oblique to the tissue (30°-145°) as compared perpendicularly (0-30°) with a median CF of 13.2 vs. 8.0 g (p decrease during the first 20 s of 11 vs. 7 Ω (p decrease in a multivariable linear regression model (p decrease, is not only dependent on the achieved catheter CF but also on catheter orientation and location.

  8. Evidence for fractional crystallization of wadsleyite and ringwoodite from olivine melts in chondrules entrained in shock-melt veins.

    Science.gov (United States)

    Miyahara, Masaaki; El Goresy, Ahmed; Ohtani, Eiji; Nagase, Toshiro; Nishijima, Masahiko; Vashaei, Zahra; Ferroir, Tristan; Gillet, Philippe; Dubrovinsky, Leonid; Simionovici, Alexandre

    2008-06-24

    Peace River is one of the few shocked members of the L-chondrites clan that contains both high-pressure polymorphs of olivine, ringwoodite and wadsleyite, in diverse textures and settings in fragments entrained in shock-melt veins. Among these settings are complete olivine porphyritic chondrules. We encountered few squeezed and flattened olivine porphyritic chondrules entrained in shock-melt veins of this meteorite with novel textures and composition. The former chemically unzoned (Fa(24-26)) olivine porphyritic crystals are heavily flattened and display a concentric intergrowth with Mg-rich wadsleyite of a very narrow compositional range (Fa(6)-Fa(10)) in the core. Wadsleyite core is surrounded by a Mg-poor and chemically stark zoned ringwoodite (Fa(28)-Fa(38)) belt. The wadsleyite-ringwoodite interface denotes a compositional gap of up to 32 mol % fayalite. A transmission electron microscopy study of focused ion beam slices in both regions indicates that the wadsleyite core and ringwoodite belt consist of granoblastic-like intergrowth of polygonal crystallites of both ringwoodite and wadsleyite, with wadsleyite crystallites dominating in the core and ringwoodite crystallites dominating in the belt. Texture and compositions of both high-pressure polymorphs are strongly suggestive of formation by a fractional crystallization of the olivine melt of a narrow composition (Fa(24-26)), starting with Mg-rich wadsleyite followed by the Mg-poor ringwoodite from a shock-induced melt of olivine composition (Fa(24-26)). Our findings could erase the possibility of the resulting unrealistic time scales of the high-pressure regime reported recently from other shocked L-6 chondrites.

  9. Varicose Veins

    Science.gov (United States)

    Varicose veins are swollen, twisted veins that you can see just under the skin. They usually occur in ... of the body. Hemorrhoids are a type of varicose vein. Your veins have one-way valves that help ...

  10. Finding a Cold Needle in a Warm Haystack: Infrared Imaging Applied to Locating Cryocooled Crystals in Loops

    Science.gov (United States)

    Snell, E. H.; vanderWoerd, M. J.; Miller, M. D.; Deacon, A. M.

    2004-01-01

    We demonstrate the use of inbred imaging to locate crystals mounted in cryoloops and cryopreserved in a nitrogen gas stream at 100K. In the home laboratory crystals are clearly seen in the infrared images with light transmitting through the sample while irradiating the crystal from behind, and with illumination from a direction perpendicular to the direction of view. The crystals transmit and reflect infrared radiation differently from the surrounding mother liquor and loop. Because of differences in contrast between crystals and their surrounding mother liquor, it is possible to clearly identify the crystal position. In use at the synchrotron, with robotically mounted crystals the small depth of field of the lens required the recording of multiple images at different focal points. Image processing techniques were then used to produce a clear image of the crystal. The resulting infrared images and intensity profiles show that infrared imaging can be a powerful complement to visual imaging in locating crystals in cryocooled loops.

  11. Spider Veins

    Science.gov (United States)

    ... How to Choose the Best Skin Care Products Spider Veins Treatment Options Learn more about treatment options ... severe venous disease. What you should know about spider veins The exact cause of spider veins is ...

  12. Tourmalines from the siderite-quartz-sulphide hydrothermal veins, Gemeric unit, western Carpathians, Slovakia: crystal chemistry and evolution

    Science.gov (United States)

    Bačík, P.; Uher, P.; Dikej, J.; Puškelová, Ľ.

    2017-03-01

    schorlitic to foititic tourmalines occur in veins located in the meta-rhyolites host, and tourmalines with the highest Mg contents occur in metabasalts.

  13. Lattice location of platinum ions implanted into single crystal zirconia and their annealing behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Cao, D.X. [Royal Melbourne Inst. of Tech., VIC (Australia); Sood, D.K. [Academia Sinica, Shanghai, SH (China). Shanghai Inst. of Nuclear Research; Brown, I.G. [Lawrence Berkeley Lab., CA (United States)

    1993-12-31

    Single crystal samples of (100) oriented cubic zirconia stabilised with 9.5 mol % yttria were implanted with platinum ions, using a metal vapour vacuum arc (MEVVA) high current ion implanter, to a nominal dose of 1x10{sup 17} ions/cm{sup 2}. The implanted samples were annealed isothermally in air ambient at 1200 deg C, from 1-24 hours. Rutherford Backscattering Spectrometry and Channeling (RBSC) of 2 MeV He ions are employed to determine depth distributions of ion damage, Pt ions and substitutionality of Pt ions before and after annealing. The damage behaviour, Pt migration and lattice location are discussed in terms of metastable phase formation and solid solubility considerations. 7 refs., 3 figs.

  14. Finding the Cold Needle in a Warm Haystack: Infrared Imaging Applied to Locating Cryo-cooled Crystals in Loops

    Science.gov (United States)

    Snell, Edward; vanderWoerd, Mark

    2003-01-01

    Thermally imaging the cryocooling processes of crystals has been demonstrated showing the progression of a cold wave through a crystal from the face closest to the origin of the coldstream ending at the point furthest away. During these studies large volume crystals were clearly distinguished from the loop holding them. Large volume crystals, used for neutron studies, were chosen deliberately to enhance the imaging. The different infrared transmission and reflectance properties of the crystal in comparison to the cryo-protectant are thought to be the parameter that produces the contrast making the crystal visible. As an application of the technology to locating crystals, more small crystals of lysozyme and a bFGF/dna complex were cryo-protected and imaged in large loops. The crystals were clearly distinguished from the vitrified solution. In the case of the bFGF/dna complex the illumination had to be carefully manipulated to enable the crystal to be seen in the visible spectrum. These preliminary results will be presented along with advantages and disadvantages of the technique and a discussion of how it might be applied.

  15. Congenital preduodenal portal vein

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Jin; Hwang, Mi Soo; Huh, Young Soo; Park, Bok Hwan [College of Medicine, Youngnam University, Gyeongsan (Korea, Republic of)

    1991-03-15

    Congenital preduodenal portal vein, first reported by Knight in 1921, is an extremely rare congenital anomaly in which the portal vein passes anteriorly to the duodenum rather than posteriorly in its normal location. It is of surgical significance because it may cause difficulties in operations involving the gall bladder, biliary duct, or duodenum. Recently, we experienced 2 cases of preduodenal portal vein. One was found during surgical exploration for the diagnosis and correction of malrotation of the bowels and the other in a 3 day-old male newborn associated with dextrocardia, situs inversus, and duodenal obstruction by diaphragm. We report these 2 cases with a review of the literature.

  16. Varicose vein - noninvasive treatment

    Science.gov (United States)

    Sclerotherapy; Laser therapy - varicose veins; Radiofrequency vein ablation; Endovenous thermal ablation; Ambulatory phlebectomy; Transilluminated power phlebotomy; Endovenous laser ablation; Varicose vein ...

  17. Lattice location of O18 in ion implanted Fe crystals by Rutherford backscattering spectrometry, channeling and nuclear reaction analysis

    Science.gov (United States)

    Vairavel, Mathayan; Sundaravel, Balakrishnan; Panigrahi, Binaykumar

    2016-09-01

    There are contradictory theoretical predictions of lattice location of oxygen interstitial atom at tetrahedral and octahedral interstices in bcc Fe. For validating these predictions, 300 keV O18 ions with fluence of 5 × 1015 ions/cm2 are implanted into bcc Fe single crystals at room temperature and annealed at 400 °C. The Rutherford backscattering spectrometry (RBS) and nuclear reaction analysis (NRA)/channeling measurements are carried out with 850 keV protons. The lattice location of implanted O18 is analysed using the α-particles yield from O18(p,α)N15 nuclear reaction. The tilt angular scans of α-particle yield along and axial directions are performed at room temperature. Lattice location of O18 is found to be at tetrahedral interstitial site by comparing the experimental scan with simulated scans using FLUX7 software.

  18. Varicose vein stripping

    Science.gov (United States)

    ... vein stripping; Venous reflux - vein stripping; Venous ulcer - veins Images Circulatory system References American Family Physician. Management of varicose veins. www.aafp.org/afp/2008/1201/p1289.html . ...

  19. Deep Vein Thrombosis

    Science.gov (United States)

    Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most deep vein ... the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem ...

  20. Hand vein recognition based on orientation of LBP

    Science.gov (United States)

    Bu, Wei; Wu, Xiangqian; Gao, Enying

    2012-06-01

    Vein recognition is becoming an effective method for personal recognition. Vein patterns lie under the skin surface of human body, and hence provide higher reliability than other biometric traits and hard to be damaged or faked. This paper proposes a novel vein feature representation method call orientation of local binary pattern (OLBP) which is an extension of local binary pattern (LBP). OLBP can represent the orientation information of the vein pixel which is an important characteristic of vein patterns. Moreover, the OLBP can also indicate on which side of the vein centerline the pixel locates. The OLBP feature maps are encoded by 4-bit binary values and an orientation distance is developed for efficient feature matching. Based on OLBP feature representation, we construct a hand vein recognition system employing multiple hand vein patterns include palm vein, dorsal vein, and three finger veins (index, middle, and ring finger). The experimental results on a large database demonstrate the effectiveness of the proposed approach.

  1. Location, location, location

    NARCIS (Netherlands)

    Anderson, S.P.; Goeree, J.K.; Ramer, R.

    1997-01-01

    We analyze the canonical location-then-price duopoly game with general log- concave consumer densities. A unique pure-strategy equilibrium to the two-stage game exists if the density is not "too asymmetric" and not "too concave." These criteria are satisfied by many commonly used densities. Equilibr

  2. Evaluation of leg varicose veins by MR venography

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Yoshifumi; Shiraishi, Tomokuni; Taira, Mitsuru [Kansai Medical Univ., Neyagawa, Osaka (Japan). Kohri Hospital; Imamura, Atsushi; Yamada, Hitoshi; Okuno, Masafumi; Kamiyama, Yasuo

    1998-11-01

    Preoperative evaluation was conducted on 30 patients with leg varicose veins by MR venography (MRV), and compared with conventional venography, MR images were performed by the 3D-SMASH Method. Compared with venography, MRV could more clearly demonstrate leg varicose veins with perforating veins than venography. It could detected fine varicose veins more than 2 mm in diameter, and deep veins. Furthermore, 3D observation enables accurate detection of the location of perforating vein. In conclusion, MRV is useful for the diagnosis of leg varicose vein. (author)

  3. Portal Vein Thrombosis

    OpenAIRE

    Hakan Demirci

    2016-01-01

    Portal vein thrombosis is an important cause of presinusoidal portal hypertension. Portal vein thrombosis commonly occurs in patient with cirrhosis, malignancy and prothrombotic states. Patients with acute portal vein thrombosis have immediate onset. Patients with chronic portal vein thrombosis have developed portal hypertension and cavernous portal transformation. Portal vein thrombosis is diagnosed with doppler ultrasound, computed tomography and magnetic resonance imaging. Therapy with low...

  4. Focus on Varicose Veins

    Science.gov (United States)

    ... veins, which are the visible purple or greenish-blue veins that appear in our legs. Spider veins or teleangiectesias are tiny veins that you ... reduce leg swelling and decrease the risk of blood clots. Prescription ... sclerosing solution into spider, reticular or varicose veins. This is a minimally ...

  5. Spider Vein Removal

    Science.gov (United States)

    Spider veins: How are they removed? I have spider veins on my legs. What options are available ... M.D. Several options are available to remove spider veins — thin red lines or weblike networks of ...

  6. Sclerotherapy of Varicose Veins and Spider Veins

    Science.gov (United States)

    ... you as to whether the procedure was a technical success when it is completed. Your interventional radiologist ... Varicose Veins) Phlebectomy of Varicose Veins Contrast Materials Anesthesia Safety Sponsored by Please note RadiologyInfo.org is ...

  7. Vein Problems Related to Varicose Veins

    Science.gov (United States)

    ... telangiectasias. Spider veins involve the capillaries, the smallest blood vessels in the body. Spider veins often appear on the legs and face. They're red or blue and usually look like a spider web or ...

  8. Portal Vein Thrombosis

    Directory of Open Access Journals (Sweden)

    Hakan Demirci

    2016-01-01

    Full Text Available Portal vein thrombosis is an important cause of presinusoidal portal hypertension. Portal vein thrombosis commonly occurs in patient with cirrhosis, malignancy and prothrombotic states. Patients with acute portal vein thrombosis have immediate onset. Patients with chronic portal vein thrombosis have developed portal hypertension and cavernous portal transformation. Portal vein thrombosis is diagnosed with doppler ultrasound, computed tomography and magnetic resonance imaging. Therapy with low molecular weight heparin achieves recanalization in more than half of acute cases.

  9. From vein precipitates to deformation and fluid rock interaction within a SSZ: Insights from the Izu-Bonin-Mariana fore arc

    Science.gov (United States)

    Micheuz, Peter; Quandt, Dennis; Kurz, Walter

    2017-04-01

    International Ocean Discovery Program (IODP) expeditions 352 and 351 drilled through oceanic crust of the Philippine Sea plate. The two study areas are located near the outer Izu-Bonin-Mariana (IBM) fore arc and in the Amami Sankaku Basin. The primary objective was to improve our understanding of supra-subduction zones (SSZ) and the process of subduction initiation. The recovered drill cores during IODP expedition 352 represent approximately 50 Ma old fore arc basalts (FAB) and boninites revealing an entire volcanic sequence of a SSZ. Expedition 351 drilled FAB like oceanic crust similar in age to the FABs of expedition 352. In this study we present data on vein microstructures, geochemical data and isotopic signatures of vein precipitates to give new insights into fluid flow and precipitation processes and deformation within the Izu-Bonin fore arc. Veins formed predominantly as a consequence of hydrofracturing resulting in the occurrence of branched vein systems and brecciated samples. Along these hydrofractures the amount of altered host rock fragments varies and locally alters the host rock completely to zeolites and carbonates. Subordinately extensional veins released after the formation of the host rocks. Cross-cutting relationships of different vein types point to multiple fracturing events subsequently filled with minerals originating from a fluid with isotopic seawater signature. Based on vein precipitates, their morphology and their growth patterns four vein types have been defined. Major vein components are (Mg-) calcite and various zeolites determined by Raman spectra and electron microprobe analyses. Zeolites result from alteration of volcanic glass during interaction with a seawaterlike fluid. Type I veins which are characterized by micritic infill represent neptunian dykes. They predominantly occur in the upper levels of drill cores being the result of an initial volume change subsequently to crystallization of the host rocks. Type II veins are

  10. Portal Vein Thrombosis

    Directory of Open Access Journals (Sweden)

    Ronny Cohen

    2015-01-01

    Full Text Available Portal vein thrombosis (PVT is the blockage or narrowing of the portal vein by a thrombus. It is relatively rare and has been linked with the presence of an underlying liver disease or prothrombotic disorders. We present a case of a young male who presented with vague abdominal symptoms for approximately one week. Imaging revealed the presence of multiple nonocclusive thrombi involving the right portal vein, the splenic vein, and the left renal vein, as well as complete occlusion of the left portal vein and the superior mesenteric vein. We discuss pathogenesis, clinical presentation, and management of both acute and chronic thrombosis. The presence of PVT should be considered as a clue for prothrombotic disorders, liver disease, and other local and general factors that must be carefully investigated. It is hoped that this case report will help increase awareness of the complexity associated with portal vein thrombosis among the medical community.

  11. Genesis of the vein-type tungsten mineralization at Nyakabingo (Rwanda) in the Karagwe-Ankole belt, Central Africa

    Science.gov (United States)

    Dewaele, S.; De Clercq, F.; Hulsbosch, N.; Piessens, K.; Boyce, A.; Burgess, R.; Muchez, Ph.

    2016-02-01

    The vein-type tungsten deposit at Nyakabingo in the central Tungsten belt of Rwanda is located in the eastern flank of the complex Bumbogo anticlinal structure. The host rock is composed of alternating sequences of sandstones, quartzites, and black pyritiferous metapelitic rocks. Two types of W-mineralized quartz veins have been observed: bedding-parallel and quartz veins that are at high angle to the bedding, which are termed crosscutting veins. Both vein types have been interpreted to have been formed in a late stage of a compressional deformation event. Both vein types are associated with small alteration zones, comprising silicification, tourmalinization, and muscovitization. Dating of muscovite crystals at the border of the veins resulted in a maximum age of 992.4 ± 1.5 Ma. This age is within error similar to the ages obtained for the specialized G4 granites (i.e., 986 ± 10 Ma). The W-bearing minerals formed during two different phases. The first phase is characterized by scheelite and massive wolframite, while the second phase is formed by ferberite pseudomorphs after scheelite. These minerals occur late in the evolution of the massive quartz veins, sometimes even in fractures that crosscut the veins. The ore minerals precipitated from a H2O-CO2-CH4-N2-NaCl-(KCl) fluid with low to moderate salinity (0.6-13.8 eq. wt% NaCl), and minimal trapping temperatures between 247 and 344 °C. The quartz veins have been crosscut by sulfide-rich veins. Based on the similar setting, mineralogy, stable isotope, and fluid composition, it is considered that both types of W-mineralized quartz veins formed during the same mineralizing event. Given the overlap in age between the G4 granites and the mineralized quartz veins, and the typical association of the W deposits in Rwanda, but also worldwide, with granite intrusions, W originated from the geochemically specialized G4 granites. Intense water-rock interaction and mixing with metamorphic fluids largely overprinted the

  12. The Crystal Structure of Lipopolysaccharide Binding Protein Reveals the Location of a Frequent Mutation that Impairs Innate Immunity

    NARCIS (Netherlands)

    Eckert, J.K.; Kim, Y. J.; Kim, J.I.; Gurtler, K.; Oh, D.Y.; Sur, S.; Lundvall, L.; Hamann, L.; Ploeg, A. van der; Pickkers, P.; Giamarellos-Bourboulis, E.; Kubarenko, A.V.; Weber, A.N.; Kabesch, M.; Kumpf, O.; An, H.J.; Lee, J.O.; Schumann, R.R.

    2013-01-01

    Lipopolysaccharide (LPS) binding protein (LBP) is an acute-phase protein that initiates an immune response after recognition of bacterial LPS. Here, we report the crystal structure of murine LBP at 2.9 A resolution. Several structural differences were observed between LBP and the related

  13. Confined crystallization of n-hexadecane located inside microcapsules or outside submicrometer silica nanospheres: a comparison study.

    Science.gov (United States)

    Fu, Dongsheng; Su, Yunlan; Gao, Xia; Liu, Yufeng; Wang, Dujin

    2013-05-23

    Crystallization and phase transition behaviors of n-hexadecane (n-C16H34, abbreviated as C16) confined in microcapsules and n-alkane/SiO2 nanosphere composites have been investigated by the combination of differential scanning calorimetry (DSC) and temperature-dependent X-ray diffraction (XRD). As evident from the DSC measurement, the surface freezing phenomenon of C16 is enhanced in both the microcapsules and SiO2 nanosphere composites because the surface-to-volume ratio is dramatically enlarged in both kinds of confinement. It is revealed from the XRD results that the novel solid-solid phase transition is observed only in the microencapsulated C16, which crystallizes into a stable triclinic phase via a mestastable rotator phase (RI). For the C16/SiO2 composite, however, no novel rotator phase emerges during the cooling process, and C16 crystallizes into a stable triclinic phase directly from the liquid state. Heterogeneous nucleation induced by the surface freezing phase is dominant in the microencapsulated sample and contributes to the emergence of the novel rotator phase, whereas heterogeneous nucleation induced by foreign crystallization nuclei dominates the C16/SiO2 composite, leading to phase transition behaviors similar to those of bulk C16.

  14. [Right ovarian vein syndrome].

    Science.gov (United States)

    Arvis, G

    1985-01-01

    Right ovarian vein syndrome is revealed in pregnancy by right lumbar pains, and even by nephritic colics. It results from a congenital malposition of the right ovarian vein, which presses the right ureter on the external iliac artery. Diagnosis is by intravenous urography and retrograde ureteral pyelography. If pain persists despite treatment by analgesics, it may be necessary to place a double-J catheter, and to operate after delivery to ligate the ovarian vein.

  15. Postpartum renal vein thrombosis.

    Science.gov (United States)

    Rubens, D; Sterns, R H; Segal, A J

    1985-01-01

    Renal vein thrombosis in adults is usually a complication of the nephrotic syndrome. Rarely, it has been reported in nonnephrotic women postpartum. The thrombosis may be a complication of the hypercoagulable state associated with both the nephrotic syndrome and pregnancy. Two postpartum patients with renal vein thrombosis and no prior history of renal disease are reported here. Neither patient had heavy proteinuria. In both cases, pyelonephritis was suspected clinically and the diagnosis of renal vein thrombosis was first suggested and confirmed by radiologic examination. Renal vein thrombosis should be considered in women presenting postpartum with flank pain.

  16. Indigenous Carbonaceous Matter and Boron Associated with Halite Crystals in Nakhla

    Science.gov (United States)

    Thomas-Keprta, K. L.; Clemett, S. J.; McKay, D. S.; Gibson, E. K.; Wentworth, S. J.

    2015-01-01

    We report here the observation of indigenous organic matter spatially associated with, and in several cases embedded within, halite crystals located in alteration veins inside the Martian meteorite Nakhla. Further-more, we have also detected enrichments of boron (B) in these halites far in excess of those previously reported in bulk Martian meteorites. Boron in Martian halites has not been detected previously.

  17. Brittle-viscous deformation of vein quartz under fluid-rich low greenschist facies conditions

    Science.gov (United States)

    Jørgen Kjøll, Hans; Viola, Giulio; Menegon, Luca; Sørensen, Bjørn

    2015-04-01

    A coarse grained, statically crystallized quartz vein with a random CPO, embedded in a phyllonitic matrix, was studied by optical microscopy, SEM imaging and EBSD to gain insights into the processes of strain localization in quartz deformed under low greenschist facies conditions at the frictional-viscous transition. The vein is located in a high strain zone at the front of an imbricate stack of Caledonian age along the northwesternmost edge of the Repparfjord Tectonic Window in northern Norway. The vein was deformed within the Nussirjavrri Fault Zone (NFZ), an out-of-sequence thrust with a phyllonitic core characterized by a ramp-flat-ramp geometry, NNW plunging stretching lineations and top-to-the SSE thrusting kinematics. Deformation conditions are typical of the frictional-viscous transition. The phyllonitic core formed at the expense of metabasalt wherein feldspar broke down to form interconnected layers of fine, synkinematic phyllosilicates. In the mechanically weak framework of the phyllonite, the studied quartz vein acted as a relatively rigid body deforming mainly by coaxial strain. Viscous deformation, related to the development of a mesoscopic pervasive extensional crenulation cleavage, was accommodated within the vein initially by basal slip of suitably oriented quartz crystals, which produced e.g. undulose extinction, extinction bands and bulging grain boundaries. In the case of misoriented quartz crystals, however, glide-accommodated dislocation creep resulted soon inefficient and led to localized dislocation tangling and strain hardening. In response to 1) hardening, 2) progressive increase of fluid pressure within the actively deforming vein and 3) increasing competence contrast between the vein and the surrounding weak, foliated phyllonitic fault core, quartz crystals began to deform frictionally along specific lattice planes oriented optimally with respect to the imposed stress field. Microfaulting generated small volumes of gouge along

  18. [Calcified deep vein thrombosis in a patient with recurrent deep vein thrombosis and sarcoidosis].

    Science.gov (United States)

    Krmek, Dubravka Zupanić; Brajković, Ivana; Bekić, Dinko; Krnić, Antun; Jurković, Petar; Pavlović, Tomislav

    2013-12-01

    In this article, we present a rare case of calcified deep vein thrombosis in a 42-year-old female patient with frequent relapses of pulmonary sarcoidosis since 1995, for which she was on maintenance therapy with corticosteroids and with consequential secondary diabetes. Recent femoral vein thrombosis was diagnosed with color Doppler in 2012. At the same time, calcified occlusive thrombus in vena cava inferior from the level of renal vein to the confluence of hepatic veins was diagnosed on abdominal multi-slice computed tomography (MSCT). Digital subtraction venography (DSV) revealed a well-developed collateral circulation through the paravertebral veins, azygos and hemiazygos vein. There were no risk factors for thrombosis other than sarcoidosis and diabetes. Deep vein thrombosis is rarely described with sarcoidosis, but according to literature reports, it usually appears as a recurrence and simultaneously at multiple locations. According to the current knowledge, we cannot say for sure whether it is a disease with an increased risk of deep vein thrombosis or there is a combination of multiple risk factors present simultaneously.

  19. What Causes Varicose Veins?

    Science.gov (United States)

    ... blood flow, and thin, stretched walls. The middle image shows where varicose veins might appear in a leg. Figure A shows ... blood flow, and thin, stretched walls. The middle image shows where varicose veins might appear in a leg. Older age or ...

  20. Automated detection of periventricular veins on 7 T brain MRI

    Science.gov (United States)

    Kuijf, Hugo J.; Bouvy, Willem H.; Zwanenburg, Jaco J. M.; Viergever, Max A.; Biessels, Geert Jan; Vincken, Koen L.

    2015-03-01

    Cerebral small vessel disease is common in elderly persons and a leading cause of cognitive decline, dementia, and acute stroke. With the introduction of ultra-high field strength 7.0T MRI, it is possible to visualize small vessels in the brain. In this work, a proof-of-principle study is conducted to assess the feasibility of automatically detecting periventricular veins. Periventricular veins are organized in a fan-pattern and drain venous blood from the brain towards the caudate vein of Schlesinger, which is situated along the lateral ventricles. Just outside this vein, a region-of- interest (ROI) through which all periventricular veins must cross is defined. Within this ROI, a combination of the vesselness filter, tubular tracking, and hysteresis thresholding is applied to locate periventricular veins. All detected locations were evaluated by an expert human observer. The results showed a positive predictive value of 88% and a sensitivity of 95% for detecting periventricular veins. The proposed method shows good results in detecting periventricular veins in the brain on 7.0T MR images. Compared to previous works, that only use a 1D or 2D ROI and limited image processing, our work presents a more comprehensive definition of the ROI, advanced image processing techniques to detect periventricular veins, and a quantitative analysis of the performance. The results of this proof-of-principle study are promising and will be used to assess periventricular veins on 7.0T brain MRI.

  1. Umbilical and portal vein calcification following umbilical vein catheterization

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, K.; Fendel, H.; Hartl, M.

    1989-07-01

    Calcifications of the umbilical vein and intrahepatic branches of the portal vein developed in a newborn who had inserted an umbilical vein catheter for 11 days postnatally. The calcified intrahepatic portal veins can still be demonstrated sonographically at the age of three years, whereby these calcifications were no longer detectable radiologically. (orig.).

  2. Quantification of deep medullary veins at 7 T brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kuijf, Hugo J.; Viergever, Max A.; Vincken, Koen L. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Bouvy, Willem H.; Razoux Schultz, Tom B.; Biessels, Geert Jan [University Medical Center Utrecht, Department of Neurology, Brain Center Rudolf Magnus, Utrecht (Netherlands); Zwanenburg, Jaco J.M. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands)

    2016-10-15

    Deep medullary veins support the venous drainage of the brain and may display abnormalities in the context of different cerebrovascular diseases. We present and evaluate a method to automatically detect and quantify deep medullary veins at 7 T. Five participants were scanned twice, to assess the robustness and reproducibility of manual and automated vein detection. Additionally, the method was evaluated on 24 participants to demonstrate its application. Deep medullary veins were assessed within an automatically created region-of-interest around the lateral ventricles, defined such that all veins must intersect it. A combination of vesselness, tubular tracking, and hysteresis thresholding located individual veins, which were quantified by counting and computing (3-D) density maps. Visual assessment was time-consuming (2 h/scan), with an intra-/inter-observer agreement on absolute vein count of ICC = 0.76 and 0.60, respectively. The automated vein detection showed excellent inter-scan reproducibility before (ICC = 0.79) and after (ICC = 0.88) visually censoring false positives. It had a positive predictive value of 71.6 %. Imaging at 7 T allows visualization and quantification of deep medullary veins. The presented method offers fast and reliable automated assessment of deep medullary veins. (orig.)

  3. Deep vein thrombosis.

    Science.gov (United States)

    Bandyopadhyay, Gargi; Roy, Subesha Basu; Haldar, Swaraj; Bhattacharya, Rabindra

    2010-12-01

    Occlusive clot formation in the veins causes venous thrombosis, the site most common in the deep veins of leg, called deep vein thrombosis. The clot can block blood flow and when it breaks off, called an embolism which in turn can damage the vital organs. Venous thrombosis occurs via three mechanisms ie, Virchow's triad. The mechanisms are decreased flow rate of blood, damage to the blood vessel wall and an increased tendency of the blood to clot. There are several factors which can increase a person's risk for deep vein thrombosis. The symptoms of deep vein thrombosis in the legs are pain, swelling and redness of the part. One variety of venous thrombosis is phlegmasia alba dolens where the leg becomes pale and cool. Investigations include Doppler ultrasound examination of the limb, D-dimer blood test, plethysmography of the legs, x-rays to show vein in the affected area (venography). Hospitalisation is necessary in some cases with some risk factors. The mainstream of treatment is with anticoagulants, mostly low molecular weight heparin for 6 months. Deep venous thrombosis is a rising problem. Early diagnosis and treatment is associated with a good prognosis.

  4. Mesenteric vein thrombosis: CT identification

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, A.; Korobkin, M.; Silverman, P.M.; Dunnick, N.R.; Kelvin, F.M.

    1984-07-01

    Superior mesenteric vein thrombosis was identified on computed tomographic scans in six patients. In each case, contrast-enhanced scans showed a high-density superior mesenteric vein wall surrounding a central filling defect. Four fo the six patients had isolated superior mesenteric vein thrombosis. A fifth patient had associated portal vein and splenic vein thrombosis, and the sixth patient had associated portal vein and inferior vena cava thrombosis. One of the six patients had acute ischemic bowel disease. The other five patients did not have acute ischemic bowel symptoms associated with their venous occlusion. This study defines the computed tomographic appearance of mesenteric vein thrombosis.

  5. Aberrant course of the umbilical vein in a newborn with Cornelia de Lange syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Toomayan, Glen A.; Gaca, Ana Maria [Duke University Medical Center, Department of Radiology, Durham, NC (United States)

    2009-04-15

    Congenital anomalies of the umbilical vein are rare. We describe an aberrant course of the umbilical vein discovered by identifying an unusual umbilical venous catheter course on abdominal radiography in a patient with Cornelia de Lange syndrome. The umbilical vein bypassed the liver to insert directly into a right pelvic vein. Use of the lateral abdominal radiograph and sonography were helpful in determining the catheter location after identifying the unusual course of the catheter on the frontal radiograph. (orig.)

  6. Internal vein texture and vein evolution of the epithermal Shila-Paula district, southern Peru

    Science.gov (United States)

    Chauvet, Alain; Bailly, Laurent; André, Anne-Sylvie; Monié, Patrick; Cassard, Daniel; Tajada, Fernando Llosa; Vargas, Juan Rosas; Tuduri, Johann

    2006-07-01

    The epithermal Shila-Paula Au-Ag district is characterized by numerous veins hosted in Tertiary volcanic rocks of the Western Cordillera (southern Peru). Field studies of the ore bodies reveal a systematic association of a main E-W vein with secondary N55-60°W veins—two directions that are also reflected by the orientation of fluid-inclusion planes in quartz crystals of the host rock. In areas where this pattern is not recognized, such as the Apacheta sector, vein emplacement seems to have been guided by regional N40°E and N40°W fractures. Two main vein-filling stages are identified. stage 1 is a quartz-adularia-pyrite-galena-sphalerite-chalcopyrite-electrum-Mn silicate-carbonate assemblage that fills the main E-W veins. stage 2, which contains most of the precious-metal mineralization, is divided into pre-bonanza and bonanza substages. The pre-bonanza substage consists of a quartz-adularia-carbonate assemblage that is observed within the secondary N45-60°W veins, in veinlets that cut the stage 1 assemblage, and in final open-space fillings. The two latter structures are finally filled by the bonanza substage characterized by a Fe-poor sphalerite-chalcopyrite-pyrite-galena-tennantite-tetrahedrite-polybasite-pearceite-electrum assemblage. The ore in the main veins is systematically brecciated, whereas the ore in the secondary veins and geodes is characteristic of open-space crystallization. Microthermometric measurements on sphalerite from both stages and on quartz and calcite from stage 2 indicate a salinity range of 0 to 15.5 wt% NaCl equivalent and homogenization temperatures bracketed between 200 and 330°C. Secondary CO2-, N2- and H2S-bearing fluid inclusions are also identified. The age of vein emplacement, based on 40Ar/39Ar ages obtained on adularia of different veins, is estimated at around 11 Ma, with some overlap between adularia of stage 1 (11.4±0.4 Ma) and of stage 2 (10.8±0.3 Ma). A three-phase tectonic model has been constructed to explain the

  7. The Distant Morphological and Petrological Features of Shock Melt Veins in the Suizhou L6 Condrite

    Energy Technology Data Exchange (ETDEWEB)

    X Xie; Z Sun; M Chen

    2011-12-31

    The morphology and petrology of distinct melt veins in the Suizhou L6 chondrite have been investigated using scanning electron microscopy, electron microprobe analyses, and Raman spectroscopy, synchrotron energy-dispersive diffraction, and transmission electron microscopy. It is found that the melt veins in the Suizhou meteorite morphologically are the simplest, straightest, and thinnest among all shock veins known from meteorites. At first glance, these veins look like fine fractures, but petrologically they are solid melt veins of chondritic composition and consist of fully crystalline materials of two distinct lithological assemblages, with no glassy material remaining. The Suizhou melt veins contain the most abundant high-pressure mineral species when compared with all other veins known in chondrites. Thus, these veins in Suizhou are classified as shock veins. All rock-forming and almost all accessory minerals in the Suizhou shock veins have been transformed to their high-pressure polymorphs, and no fragments of the precursor minerals remain in the veins. Among the 11 high-pressure mineral phases identified in the Suizhou veins, three are new high-pressure minerals, namely, tuite after whitlockite, xieite, and the CF phase after chromite. On the basis of transformation of plagioclase into maskelynite, it is estimated that the Suizhou meteorite experienced shock pressures and shock temperatures up to 22 GPa and 1000 C, respectively. Shearing and friction along shock veins raised the temperature up to 1900-2000 C and the pressure up to 24 GPa within the veins. Hence, phase transition and crystallization of high-pressure minerals took place only in the Suizhou shock veins. Fast cooling of the extremely thin shock veins is regarded as the main reason that up to 11 shock-induced high-pressure mineral phases could be preserved in these veins.

  8. Influence of pH, layer charge location and crystal thickness distribution on U(VI) sorption onto heterogeneous dioctahedral smectite

    Energy Technology Data Exchange (ETDEWEB)

    Guimarães, Vanessa [Instituto de Ciências da Terra – Porto, DGAOT, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal); Geobiotec. Departamento de Geociências da Universidade de Aveiro, Campo Universitário de Santiago, 3810-193 Aveiro (Portugal); Rodríguez-Castellón, Enrique; Algarra, Manuel [Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Málaga. Campus de Teatino s/n, 29071 Málaga (Spain); Rocha, Fernando [Geobiotec. Departamento de Geociências da Universidade de Aveiro, Campo Universitário de Santiago, 3810-193 Aveiro (Portugal); Bobos, Iuliu, E-mail: ibobos@fc.up.pt [Instituto de Ciências da Terra – Porto, DGAOT, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal)

    2016-11-05

    Highlights: • The UO{sub 2}{sup 2+} sorption at pH 4 and 6 on heterogeneous smectite structure. • The cation exchange process is affected by layer charge distribution. • Surface complexation and cation exchange modelling. • New binding energy components identified by X-ray photoelectron spectroscopy. - Abstract: The UO{sub 2}{sup 2+} adsorption on smectite (samples BA1, PS2 and PS3) with a heterogeneous structure was investigated at pH 4 (I = 0.02 M) and pH 6 (I = 0.2 M) in batch experiments, with the aim to evaluate the influence of pH, layer charge location and crystal thickness distribution. Mean crystal thickness distribution of smectite crystallite used in sorption experiments range from 4.8 nm (sample PS2), to 5.1 nm (sample PS3) and, to 7.4 nm (sample BA1). Smaller crystallites have higher total surface area and sorption capacity. Octahedral charge location favor higher sorption capacity. The sorption isotherms of Freundlich, Langmuir and SIPS were used to model the sorption experiments. The surface complexation and cation exchange reactions were modeled using PHREEQC-code to describe the UO{sub 2}{sup 2+} sorption on smectite. The amount of UO{sub 2}{sup 2+} adsorbed on smectite samples decreased significantly at pH 6 and higher ionic strength, where the sorption mechanism was restricted to the edge sites of smectite. Two binding energy components at 380.8 ± 0.3 and 382.2 ± 0.3 eV, assigned to hydrated UO{sub 2}{sup 2+} adsorbed by cation exchange and by inner-sphere complexation on the external sites at pH 4, were identified after the U4f{sub 7/2} peak deconvolution by X-photoelectron spectroscopy. Also, two new binding energy components at 380.3 ± 0.3 and 381.8 ± 0.3 eV assigned to ≡AlOUO{sub 2}{sup +} and ≡SiOUO{sub 2}{sup +} surface species were observed at pH 6.

  9. Deep Vein Thrombosis

    Centers for Disease Control (CDC) Podcasts

    2012-04-05

    This podcast discusses the risk for deep vein thrombosis in long-distance travelers and ways to minimize that risk.  Created: 4/5/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 4/5/2012.

  10. Retinal vein occlusion

    Science.gov (United States)

    ... decrease the risk of retinal vein occlusion. These measures include: Eating a low-fat diet Getting regular exercise Maintaining an ideal weight Not smoking Aspirin or other blood thinners may help prevent blockages in the other eye. Controlling diabetes may ...

  11. The vein collar

    DEFF Research Database (Denmark)

    Lundgren, F; Schroeder, Torben Veith

    2012-01-01

    Randomized studies evaluating the effect of a vein collar at the distal anastomosis of PTFE-grafts show conflicting results. The study of the Joint Vascular Research Group (JVRG) of UK found improved primary patency while the Scandinavian Miller Collar Study (SCAMICOS) found neither any effect...

  12. Deep Vein Thrombosis

    African Journals Online (AJOL)

    OWNER

    Il s'agissait de la main et les recherches en ligne. Des termes ..... Cerrato D, Ariano G, and Fiacchino F : Deep vein ... Surg 1988; 75: 1053–7. 19. Salzman ... Alikhan R, Cohen AT, Combe S, Samama .... Kakkar AK, Williamson RCN. Thrombo.

  13. [Ovarian vein syndrome].

    Science.gov (United States)

    Ferrero Doria, R; Guzmán Valls, P; López Alba, J; Tomás Ros, M; Rico Galiano, J L; Fontana Compiano, L O

    1996-04-01

    The Ovarian Vein Syndrome has been the subject of controversy ever since first described as such by Clark in 1964. This is an uncommon entity within urologic sings and symptoms which appears as a recurrent nephritic colic coinciding with menstruation or during the immediately preceding days. The authors review a clinical case from our Urology Service, including some considerations on the case.

  14. Cucumber vein yellowing virus

    Science.gov (United States)

    Cucurbits are an important crop of temperate, subtropical and tropical regions of the world. Cucumber vein yellowing virus (CVYV) is a major viral pathogen of cucurbits. This chapter provides an overview of the biology of CVYV and the disease it causes....

  15. Squash vein yellowing virus

    Science.gov (United States)

    Cucurbits are an important crop of temperate, subtropical and tropical regions of the world. Squash vein yellowing virus (SqVYV) is a major viral pathogen of cucurbits. This chapter provides an overview of the biology of SqVYV and the disease it causes....

  16. Endovenous treatments for varicose veins

    NARCIS (Netherlands)

    R.R. van den Bos (Renate)

    2011-01-01

    textabstractEndovenous treatment is currently one of the most frequently used methods for treating varicose veins in the Netherlands. Varicose veins are tortuous and enlarged veins due to weakening in the vein’s wall or valves. They are manifestations of chronic venous disease (CVD), which may lead

  17. Substitution mechanisms and location of Co2+ ions in congruent and stoichiometric lithium niobate crystals derived from electron paramagnetic resonance data

    Science.gov (United States)

    Grachev, V. G.; Hansen, K.; Meyer, M.; Kokanyan, E. P.; Malovichko, G. I.

    2017-03-01

    Electron paramagnetic resonance (EPR) spectra and their angular dependencies were measured for Co2+ trace impurities in stoichiometric samples of lithium niobate doped with rhodium. It was found that Co2+ substitutes for Li+ in the dominant axial center (CoLi) and that the principal substitution mechanism in stoichiometric lithium niobate is 4Co2+ ↔ 3Li+  +  Nb5+. The four Co2+ ions can occupy the nearest possible cation sites by occupying a Nb site and its three nearest-neighbor Li sites, creating a trigonal pyramid with C3 symmetry, as well as non-neighboring sites (e.g. a CoNb-CoLi pair at the nearest sites on the C3 axis with two nearby isolated single Co2+ ions substituted for Li+). In congruent crystals and samples with Li content enriched by vapor transport equilibrium treatment the excess charge of the Co2+ centers is compensated by lithium vacancies located rather far from the Co2+ ions for the dominant axial center or in the nearest neighborhood for low-symmetry satellite centers (the Co2+ ↔ 2Li+ substitution mechanism). The use of exact numerical diagonalization of the spin-Hamiltonian matrices explains all the details of the EPR spectra and gives a value for hyperfine interaction A || that is several times smaller than that obtained using perturbation formulae. The refined values of A and g-tensor components can be used as reliable cornerstones for ab initio and cluster calculations.

  18. Varicosity of the pulmonary veins

    Energy Technology Data Exchange (ETDEWEB)

    Leicher-Dueber, A.; Lindner, P.; Schild, H.; Plewe, G.

    1986-04-01

    Varicosity of the pulmonary veins is a rare anomaly of the pulmonary vascular system. The varices do not usually change in size over years, do not cause symptoms and need no therapy. However, raised left atrial pressure can cause increase in the diameter of pulmonary vein varices. A case of lung vein varicosity in the right middle and upper lobe associated with coarctation of the aorta and an anomalous upper-middle lobe vein was observed over a period of 10 years. Increase in left atrial pressure (aortic and relative mitral regurgitation) led to enlargement of the pulmonary veins.

  19. Formation of Archean batholith-hosted gold veins at the Lac Herbin deposit, Val-d'Or district, Canada: Mineralogical and fluid inclusion constraints

    Science.gov (United States)

    Rezeau, Hervé; Moritz, Robert; Beaudoin, Georges

    2017-03-01

    The Lac Herbin deposit consists of a network of mineralized, parallel steep-reverse faults within the synvolcanic Bourlamaque granodiorite batholith at Val-d'Or in the Archean Abitibi greenstone belt. There are two related quartz-tourmaline-carbonate fault-fill vein sets in the faults, which consist of subvertical fault-fill veins associated with subhorizontal veins. The paragenetic sequence is characterized by a main vein filling ore stage including quartz, tourmaline, carbonate, and pyrite-hosted gold, chalcopyrite, tellurides, pyrrhotite, and cubanite inclusions. Most of the gold is located in fractures in deformed pyrite and quartz in equilibrium with chalcopyrite and carbonates, with local pyrrhotite, sphalerite, galena, cobaltite, pyrite, or tellurides. Petrography and microthermometry on quartz from the main vein filling ore stage reveal the presence of three unrelated fluid inclusion types: (1) gold-bearing aqueous-carbonic inclusions arranged in three-dimensional intragranular clusters in quartz crystals responsible for the main vein filling stage, (2) barren high-temperature, aqueous, moderately saline inclusions observed in healed fractures, postdating the aqueous-carbonic inclusions, and considered as a remobilizing agent of earlier precipitated gold in late fractures, and (3) barren low-temperature, aqueous, high saline inclusions in healed fractures, similar to the crustal brines reported throughout the Canadian Shield and considered to be unrelated to the gold mineralization. At the Lac Herbin deposit, the aqueous-carbonic inclusions are interpreted to have formed first and to represent the gold-bearing fluid, which were generated contemporaneous with regional greenschist facies metamorphism. In contrast, the high-temperature aqueous fluid dissolved gold from the main vein filling ore stage transported and reprecipitated it in late fractures during a subsequent local thermal event.

  20. Autogenous Sapheonus Vein Graft Interposition in Arteriovenous Fistula Formation

    Directory of Open Access Journals (Sweden)

    Alper Uzun

    2013-10-01

    Full Text Available Aim: Other techniques are required due to the negative influence of poor superficial venous system calibration (<1.5-2 mm to the long term patency of the arteriovenous fistula which is documented via preoperative Doppler ultrasound examination. The postoperative outcome of 32 patients were compared prospectively whom autologous saphenous vein bridge graft was interposed between brachial artery/high brachial vein and radial artery/basilic vein. Material and Method: Patients were divided into two groups; patients whom radial artery/basilic vein autologous saphenous vein graft interposition was performed were labelled as Group 1 (17 patients while patients whom brachial artery/high brachial vein autologous saphenous vein graft was interpositioned were labelled as Group 2 (15 patients. Patients were followed up for 12 months. Graft related complications were recorded. Primary and secondary patency rate were calculated. Results: Graft infection, edema or ischemia of the hand or arm, congestive heart failure and mortality was not observed. There was not a significant difference in puncture site complications between two groups. Primary patency rate was 76.5% (13 of 17 in Group 1 while it was 93.3% (14 of 15 for Group 2 (p=0,185. Secondary patency rate was 82.4% (14 of 17 in Group1 and 100% (15 of 15 for Group 2 (p=0.093. Primary and secondary patency rate were similar between two groups. Discussion: We sought to compare the complication and patency rate of the proximal (brachial artery/high brachial vein and distal (radial artery/basilic vein located bridge graft interpositions and could not found statistical difference between two groups. It is reasonable to keep proximal regions for further interventions, so radial artery/basilic vein bridge graft interposition can be recommended as the initial option according to our findings.

  1. Retroaortic left renal vein joining the left common iliac vein

    Energy Technology Data Exchange (ETDEWEB)

    Brancatelli, G.; Galia, M.; Finazzo, M.; Sparacia, G.; Pardo, S.; Lagalla, R. [Dept. of Radiology ' ' P. Cignolini' ' , Univ. of Palermo (Italy)

    2000-11-01

    Retroaortic left renal vein joining the left common iliac vein is a rare congenital anomaly in the development of the inferior vena cava. To our knowledge, only one case has been reported in the literature; however, its imaging features have never been described. A 27-year-old male presented with a 1-year history of recurrent right flank pain, dysuria, hematuria, and fever (39 C). Computed tomography and MR venography showed a retroaortic left renal vein joining the left common iliac vein. We present the CT and MR venography findings and discuss their feasibility in showing this congenital anomaly. (orig.)

  2. A RARE CASE OF EXTENSIVE THROMBOSIS OF INFERIOR VENA CAVA, PORTAL VEIN, SPLENIC VEIN AND SUPERIOR MESENTRIC VEIN

    Directory of Open Access Journals (Sweden)

    Giridhar

    2015-03-01

    Full Text Available While the most common presentation of venous thromboembolic disease is deep vein thrombosis (DVT or pulmonary thromboembolism, rarer manifestations are thrombosis of jugular vein, cerebral sinus and inferior vena cava. Here we are presenting a rare case of inferior vena caval thrombosis with multiple thrombus in portal vein, splenic vein and superior mesenteric vein

  3. Cephalic vein aneurysm.

    Science.gov (United States)

    Faraj, Walid; Selmo, Francesca; Hindi, Mia; Haddad, Fadi; Khalil, Ismail

    2007-11-01

    Cephalic vein aneurysms are rare malformations that may develop in any part of the vascular system, and their history, presentation, and management vary depending on their site. The etiology of venous aneurysms remains unclear, although several theories have been elaborated. Venous aneurysms are unusual vascular malformations that occur equally between the sexes and are seen at any age; they can present as either a painful or a painless subcutaneous mass. No serious complications have been reported from upper extremity venous aneurysms. Surgical excision is the definitive management for most of these. The case reported here presented with a painless and mobile, soft, subcutaneous mass that caused only cosmetic concern.

  4. Palm Vein Verification Using Multiple Features and Locality Preserving Projections

    Directory of Open Access Journals (Sweden)

    Ali Mohsin Al-juboori

    2014-01-01

    Full Text Available Biometrics is defined as identifying people by their physiological characteristic, such as iris pattern, fingerprint, and face, or by some aspects of their behavior, such as voice, signature, and gesture. Considerable attention has been drawn on these issues during the last several decades. And many biometric systems for commercial applications have been successfully developed. Recently, the vein pattern biometric becomes increasingly attractive for its uniqueness, stability, and noninvasiveness. A vein pattern is the physical distribution structure of the blood vessels underneath a person’s skin. The palm vein pattern is very ganglion and it shows a huge number of vessels. The attitude of the palm vein vessels stays in the same location for the whole life and its pattern is definitely unique. In our work, the matching filter method is proposed for the palm vein image enhancement. New palm vein features extraction methods, global feature extracted based on wavelet coefficients and locality preserving projections (WLPP, and local feature based on local binary pattern variance and locality preserving projections (LBPV_LPP have been proposed. Finally, the nearest neighbour matching method has been proposed that verified the test palm vein images. The experimental result shows that the EER to the proposed method is 0.1378%.

  5. Preliminary Study for Designing a Novel Vein-Visualizing Device

    Directory of Open Access Journals (Sweden)

    Donghoon Kim

    2017-02-01

    Full Text Available Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms.

  6. Preliminary Study for Designing a Novel Vein-Visualizing Device.

    Science.gov (United States)

    Kim, Donghoon; Kim, Yujin; Yoon, Siyeop; Lee, Deukhee

    2017-02-07

    Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR) light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms.

  7. Palm vein verification using multiple features and locality preserving projections.

    Science.gov (United States)

    Al-Juboori, Ali Mohsin; Bu, Wei; Wu, Xiangqian; Zhao, Qiushi

    2014-01-01

    Biometrics is defined as identifying people by their physiological characteristic, such as iris pattern, fingerprint, and face, or by some aspects of their behavior, such as voice, signature, and gesture. Considerable attention has been drawn on these issues during the last several decades. And many biometric systems for commercial applications have been successfully developed. Recently, the vein pattern biometric becomes increasingly attractive for its uniqueness, stability, and noninvasiveness. A vein pattern is the physical distribution structure of the blood vessels underneath a person's skin. The palm vein pattern is very ganglion and it shows a huge number of vessels. The attitude of the palm vein vessels stays in the same location for the whole life and its pattern is definitely unique. In our work, the matching filter method is proposed for the palm vein image enhancement. New palm vein features extraction methods, global feature extracted based on wavelet coefficients and locality preserving projections (WLPP), and local feature based on local binary pattern variance and locality preserving projections (LBPV_LPP) have been proposed. Finally, the nearest neighbour matching method has been proposed that verified the test palm vein images. The experimental result shows that the EER to the proposed method is 0.1378%.

  8. Preliminary Study for Designing a Novel Vein-Visualizing Device

    Science.gov (United States)

    Kim, Donghoon; Kim, Yujin; Yoon, Siyeop; Lee, Deukhee

    2017-01-01

    Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR) light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms. PMID:28178227

  9. Image Registration of Cone-Beam Computer Tomography and Preprocedural Computer Tomography Aids in Localization of Adrenal Veins and Decreasing Radiation Dose in Adrenal Vein Sampling

    NARCIS (Netherlands)

    Busser, W.M.H.; Arntz, M.; Jenniskens, S.F.M.; Deinum, J.; Hoogeveen, Y.L.; Lange, F. de; Schultze Kool, L.J.

    2015-01-01

    We assessed whether image registration of cone-beam computed tomography (CT) (CBCT) and contrast-enhanced CT (CE-CT) images indicating the locations of the adrenal veins can aid in increasing the success rate of first-attempts adrenal vein sampling (AVS) and therefore decreasing patient radiation do

  10. Historical Overview of Varicose Vein Surgery

    NARCIS (Netherlands)

    van den Bremer, Jephta; Moll, Frans L.

    2010-01-01

    Varicose veins are as old as Hippocrates. Varicose vein treatments come and go. Surgery for varicose vein disease is one of the commonest elective general surgical procedures. The history of varicose vein surgery has been traced. We note the first descriptions of varicose veins, and we particularly

  11. Anatomical variation of thyroid veins on contrast-enhanced multi-detector row computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, Hayato, E-mail: m04149@yahoo.co.jp [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Yamada, Takayuki; Murakami, Kenji; Hashimoto, Kazuki; Tazawa, Yoko; Kumano, Reiko [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Nakajima, Yasuo [Department of Radiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511 (Japan)

    2015-05-15

    Highlights: • This is the first study to demonstrate the anatomy of thyroid veins on contrasted-enhanced MDCT. • Identifying the thyroid vein on MDCT prior to selective venous sampling of parathyroid hormone provides clinical information to interventional radiologist. • Detecting especially the inferior thyroid veins with individual variability in numbers, locations, and lengths may have an effect on SVS for HPT and decrease the difficulty and time of the procedure. - Abstract: Objective: The objective of this study was to clarify the anatomical variation of thyroid veins into the systemic vein using contrast-enhanced multi-detector row computed tomography (MDCT). Design and methods: : The subjects were 80 patients (34 males and 46 females; mean age, 50.1 years; age range, 15–92 years) with neck diseases who underwent MDCT. The number and location of inflow points of the thyroid veins into the systemic vein, and the length from the junction of bilateral brachiocephalic veins to the orifice of inferior thyroid vein were investigated by reviewing the axial and coronal images. Results: All superior thyroid veins were detected. Right and left middle thyroid veins were identified in 39 and 29 patients, respectively. Right inferior thyroid veins, left inferior thyroid veins, and common trunks were detected in 43, 46, and 39 patients, respectively; in five patients, two left thyroid veins were identified. All left inferior thyroid veins and 34 common trunks flowed into the innominate vein, while right ones had some variations in inflow sites. Mean lengths were 3.01 ± 1.30 cm (range, 0.5–6.19) and 2.04 ± 0.91 cm (0.5–4.4) in the left inferior thyroid vein and common trunk, and 1.96 ± 1.05 cm (0.81–4.8) and 1.65 ± 0.69 cm (0.63–2.94) in the right one flowing into the right internal jugular vein and the innominate vein, respectively. Conclusions: The numbers and orifices of thyroid veins were identified at high rates on contrast-enhanced MDCT. This

  12. Extrahepatic portal vein aneurysm: Two case reports of surgical intervention

    Institute of Scientific and Technical Information of China (English)

    Bi Jin; Yuan Sun; Yi-Qing Li; Yu-Guo Zhao; Chuan-Shan Lai; Xian-Song Feng; Chi-Dan Wan

    2005-01-01

    We report two cases of extrahepatic portal vein aneurysm,and both of them underwent surgical intervention. The first case had a mild pain in right upper quadrant of the abdomen; the second had no obvious symptoms. Physical examination revealed nothing abnormal. Both of them were diagnosed by magnetic resonance imaging angiography (MRA). One of the aneurysms was located at the main portal vein, the other, at the confluence of the superior mesenteric vein and the splenic vein, and these two places are exactly the most common locations of the extrahepatic portal vein aneurysm reported in the literature (30.7% each site). The first case underwent aneurysmorrhaphy and the second case, aneurysm resection with splenectomy. Both of them recovered soon after the operation, and the symptom of the first case was greatly alleviated. During the follow-up of half a year, no complication and adverse effect of surgical intervention was found and the color Doppler ultrasonography revealed no recurrence of the aneurysmal dilation. We suggest that surgical intervention can alleviate the symptom of the extrahepatic portal vein aneurysm and prevent its complications effectively and safely for low risk patients.

  13. phenoVein - A software tool for leaf vein segmentation and analysis

    OpenAIRE

    Bühler, Jonas; Rishmawi, Louai; Pflugfelder, Daniel; Huber, Gregor; Scharr, Hanno; Hülskamp, Martin; Koornneef, Maarten; SCHURR, ULRICH; Jahnke, Siegfried

    2015-01-01

    phenoVein is a software tool dedicated to automated segmenting and analyzing images of leaf veins. It includes comfortable manual correction features. Advanced image filtering automatically emphasizes veins from background and compensates for local brightness inhomogeneities. Phenotypical leaf vein traits being calculated are total vein density, vein lengths and widths and skeleton graph statistics. For determination of vein widths, a model based vein edge estimation approach has been impleme...

  14. Leiomyosarcoma of the renal vein

    Directory of Open Access Journals (Sweden)

    Lemos Gustavo C.

    2003-01-01

    Full Text Available Leiomyosarcoma of the renal vein is a rare tumor of complex diagnosis. We presented a case of renal vein leiomyosarcoma detected in a routine study. The primary treatment was complete surgical removal of the mass. In cases where surgical removal is not possible the prognosis is poor, with high rates of local recurrence and distant spread.

  15. Agenesis of the iliac veins.

    Science.gov (United States)

    Thomas, M L; Posniak, H V

    1984-01-01

    Three case reports of patients with the rare anomaly of agenesis of the iliac veins are presented. It is emphasised that full phlebographic investigation should be carried out in such patients before surgical treatment is considered. It is pointed out that surgical ablation may exacerbate the symptoms of leg swelling and varicose veins for which the patients seek advice.

  16. Infrared imaging of varicose veins

    Science.gov (United States)

    Noordmans, Herke Jan; de Zeeuw, Raymond; Verdaasdonk, Ruud M.; Wittens, Cees H. A.

    2004-06-01

    It has been established that varicose veins are better visualized with infrared photography. As near-infrared films are nowadays hard to get and to develop in the digital world, we investigated the use of digital photography of varicose veins. Topics that are discussed are illumination setup, photography and digital image enhancement and analysis.

  17. 10-Minute Conultation Varicose veins

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    A 55 year old woman presents with a history of tortuous veins on both legs and a related ache towards the end of the day.She finds these veins unsightly and would like to know whether she can have them treated.

  18. Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins.

    Science.gov (United States)

    Baltsavias, Gerasimos; Parthasarathi, Venkatraman; Aydin, Emre; Al Schameri, Rahman A; Roth, Peter; Valavanis, Anton

    2015-04-01

    We reviewed the anatomy and embryology of the bridging and emissary veins aiming to elucidate aspects related to the cranial dural arteriovenous fistulae. Data from relevant articles on the anatomy and embryology of the bridging and emissary veins were identified using one electronic database, supplemented by data from selected reference texts. Persisting fetal pial-arachnoidal veins correspond to the adult bridging veins. Relevant embryologic descriptions are based on the classic scheme of five divisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon). Variation in their exact position and the number of bridging veins is the rule and certain locations, particularly that of the anterior cranial fossa and lower posterior cranial fossa are often neglected in prior descriptions. The distal segment of a bridging vein is part of the dural system and can be primarily involved in cranial dural arteriovenous lesions by constituting the actual site of the shunt. The veins in the lamina cribriformis exhibit a bridging-emissary vein pattern similar to the spinal configuration. The emissary veins connect the dural venous system with the extracranial venous system and are often involved in dural arteriovenous lesions. Cranial dural shunts may develop in three distinct areas of the cranial venous system: the dural sinuses and their interfaces with bridging veins and emissary veins. The exact site of the lesion may dictate the arterial feeders and original venous drainage pattern.

  19. Sagittal vein thrombosis caused by central vein catheter.

    Directory of Open Access Journals (Sweden)

    Feridoun Sabzi

    2015-03-01

    Full Text Available Cerebral venous thrombosis, including thrombosis of cerebral veins and major dural sinuses, is an uncommon disorder in the general population. However, it has a higher frequency among patients younger than 40 years of age, patients with thrombophilia, pregnant patients or those receiving hormonal contraceptive therapy or has foreign body such as catheter in their veins or arterial system. In this case report, we described clinical and radiological findings in a patient with protein C-S deficiency and malposition of central vein catheter.

  20. Central Retinal Vein Occlusion Revealing Coelic Disease

    Directory of Open Access Journals (Sweden)

    Hana ZOUBEIDI

    2016-11-01

    Full Text Available Introduction: Thrombosis has been widely reported in coeliac disease (CD but central retinal vein occlusion (CRVO is rarely described. Case presentation: A 27-year-old woman presented with acute visual loss and was diagnosed with CRVO. Her protein S and protein C levels were low and CD was diagnosed on the basis of endoscopic, immunological and histological results. A gluten-free diet resulted in favourable evolution. Conclusion: CD should be considered in young patients with thrombosis, especially if in an unusual location. Treatment is based on a gluten-free diet.

  1. Vein matching using artificial neural network in vein authentication systems

    Science.gov (United States)

    Noori Hoshyar, Azadeh; Sulaiman, Riza

    2011-10-01

    Personal identification technology as security systems is developing rapidly. Traditional authentication modes like key; password; card are not safe enough because they could be stolen or easily forgotten. Biometric as developed technology has been applied to a wide range of systems. According to different researchers, vein biometric is a good candidate among other biometric traits such as fingerprint, hand geometry, voice, DNA and etc for authentication systems. Vein authentication systems can be designed by different methodologies. All the methodologies consist of matching stage which is too important for final verification of the system. Neural Network is an effective methodology for matching and recognizing individuals in authentication systems. Therefore, this paper explains and implements the Neural Network methodology for finger vein authentication system. Neural Network is trained in Matlab to match the vein features of authentication system. The Network simulation shows the quality of matching as 95% which is a good performance for authentication system matching.

  2. Neonatal renal vein thrombosis.

    Science.gov (United States)

    Brandão, Leonardo R; Simpson, Ewurabena A; Lau, Keith K

    2011-12-01

    Neonatal renal vein thrombosis (RVT) continues to pose significant challenges for pediatric hematologists and nephrologists. The precise mechanism for the onset and propagation of renal thrombosis within the neonatal population is unclear, but there is suggestion that acquired and/or inherited thrombophilia traits may increase the risk for renal thromboembolic disease during the newborn period. This review summarizes the most recent studies of neonatal RVT, examining its most common features, the prevalence of acquired and inherited prothrombotic risk factors among these patients, and evaluates their short and long term renal and thrombotic outcomes as they may relate to these risk factors. Although there is some consensus regarding the management of neonatal RVT, the most recent antithrombotic therapy guidelines for the management of childhood thrombosis do not provide a risk-based algorithm for the acute management of RVT among newborns with hereditary prothrombotic disorders. Whereas neonatal RVT is not a condition associated with a high mortality rate, it is associated with significant morbidity due to renal impairment. Recent evidence to evaluate the effects of heparin-based anticoagulation and thrombolytic therapy on the long term renal function of these patients has yielded conflicting results. Long term cohort studies and randomized trials may be helpful to clarify the impact of acute versus prolonged antithrombotic therapy for reducing the morbidity that is associated with neonatal RVT.

  3. Portal flow into the liver through veins at the site of biliary-enteric anastomosis.

    Science.gov (United States)

    Hashimoto, M; Heianna, J; Yasuda, K; Tate, E; Watarai, J; Shibata, S; Sato, T; Yamamoto, Y

    2005-07-01

    The aim of this study was to establish the role played by jejunal veins in hepatopetal flow after biliary-enteric anastomosis and to evaluate the helical CT features of hepatopetal flow through the anastomosis. We retrospectively analyzed helical CT images of the liver in 31 patients with biliary-enteric anastomosis who underwent hepatic angiography with (n=13) or without (n=18) CT arterial portography within 2 weeks of the CT examination during the last 4 years. Arterial portography showed hepatopetal flow through small vessels located (communicating veins) between the elevated jejunal veins and the intrahepatic portal branches in two (9%) of 22 patients with a normal portal system. Helical CT showed focal parenchymal enhancement around the anastomosis in these two patients. All nine patients with extrahepatic portal vein occlusion (100%) had hepatopetal flow through the anastomosis, and four of the nine had decreased portal flow. CT revealed small communicating veins in two of these four patients. In five patients with normal portal perfusion despite extrahepatic portal vein occlusion, CT detected dilated communicating veins and elevated jejunal veins. The presence of communicating veins and/or focal parenchymal enhancement around the anastomosis indicates hepatopetal flow through the elevated jejunal veins.

  4. Computer-assisted diagnostic tool to quantify the pulmonary veins in sickle cell associated pulmonary hypertension

    Science.gov (United States)

    Jajamovich, Guido H.; Pamulapati, Vivek; Alam, Shoaib; Mehari, Alem; Kato, Gregory J.; Wood, Bradford J.; Linguraru, Marius George

    2012-03-01

    Pulmonary hypertension is a common cause of death among patients with sickle cell disease. This study investigates the use of pulmonary vein analysis to assist the diagnosis of pulmonary hypertension non-invasively with CT-Angiography images. The characterization of the pulmonary veins from CT presents two main challenges. Firstly, the number of pulmonary veins is unknown a priori and secondly, the contrast material is degraded when reaching the pulmonary veins, making the edges of these vessels to appear faint. Each image is first denoised and a fast marching approach is used to segment the left atrium and pulmonary veins. Afterward, a geodesic active contour is employed to isolate the left atrium. A thinning technique is then used to extract the skeleton of the atrium and the veins. The locations of the pulmonary veins ostia are determined by the intersection of the skeleton and the contour of the atrium. The diameters of the pulmonary veins are measured in each vein at fixed distances from the corresponding ostium, and for each distance, the sum of the diameters of all the veins is computed. These indicators are shown to be significantly larger in sickle-cell patients with pulmonary hypertension as compared to controls (p-values < 0.01).

  5. The Role of Pulmonary Veins in Cancer Progression from a Computed Tomography Viewpoint

    Science.gov (United States)

    Chang, Hung; Liao, Tzu-Yao; Wen, Ming-Sheng; Yu, Chih-Teng

    2016-01-01

    Background. We studied the role of pulmonary veins in cancer progression using computed tomography (CT) scans. Methods. We obtained data from 260 patients with pulmonary vein obstruction syndrome (PVOS). We used CT scans to investigate pulmonary lesions in relation to pulmonary veins. We divided the lesions into central and peripheral lesions by their anatomical location: in the lung parenchymal tissue or pulmonary vein; in the superior or inferior pulmonary vein; and by unilateral or bilateral presence in the lungs. Results. Of the 260 PVOS patients, 226 (87%) had central lesions, 231 (89%) had peripheral lesions, and 190 (75%) had mixed central and peripheral lesions. Among the 226 central lesions, 93% had lesions within the superior pulmonary vein, either bilaterally or unilaterally. Among the 231 peripheral lesions, 65% involved bilateral lungs, 70% involved lesions within the inferior pulmonary veins, and 23% had obvious metastatic extensions into the left atrium. All patients exhibited nodules within their pulmonary veins. The predeath status included respiratory failure (40%) and loss of consciousness (60%). Conclusion. CT scans play an important role in following tumor progression within pulmonary veins. Besides respiratory distress, PVOS cancer cells entering centrally can result in cardiac and cerebral events and loss of consciousness or can metastasize peripherally from the pulmonary veins to the lungs.

  6. A Vein Map Biometric System

    Directory of Open Access Journals (Sweden)

    Felix Fuentes

    2013-08-01

    Full Text Available There is increasing demand world-wide, from government agencies and the private sector for cutting-edge biometric security technology that is difficult to breach but userfriendly at the same time. Some of the older tools, such as fingerprint, retina and iris scanning, and facial recognition software have all been found to have flaws and often viewed negatively because of many cultural and hygienic issues associated with them. Comparatively, mapping veins as a human barcode, a new technology, has many advantages over older technologies. Specifically, reproducing a three-dimensional model of a human vein system is impossible to replicate. Vein map technology is distinctive because of its state-of-the-art sensors are only able to recognize vein patterns if hemoglobin is actively flowing through the person

  7. [Surgery of essential varicose veins].

    Science.gov (United States)

    Maraval, M

    1994-03-15

    Idiopathic varicose veins of the lower limbs are a frequent but benign disorder. Surgery is only a moment in the course of the disease. Although not the only treatment of essential varicose veins, surgery by an experienced team performing crossectomy, stripping by intussusception using a stripper, and phlebectomy gives fully satisfactory results, both to patient and to physician, in over 80% of cases. New techniques were recently developed that, at present, have not confirmed early hopes.

  8. Portal Vein Thrombosis in non cirrhotic patients

    NARCIS (Netherlands)

    M.C.W. Spaander (Manon)

    2010-01-01

    textabstractExtrahepatic portal vein thrombosis (EPVT) is the most common cause of portal hypertension in non- cirrhotic patients. EPVT has been defined as an obstruction of the extrahepatic portal vein with or without involvement of the intrahepatic portal veins. Although the portal vein accounts f

  9. Location Privacy

    Science.gov (United States)

    Meng, Xiaofeng; Chen, Jidong

    With rapid development of sensor and wireless mobile devices, it is easy to access mobile users' location information anytime and anywhere. On one hand, LBS is becoming more and more valuable and important. On the other hand, location privacy issues raised by such applications have also gained more attention. However, due to the specificity of location information, traditional privacy-preserving techniques in data publishing cannot be used. In this chapter, we will introduce location privacy, and analyze the challenges of location privacy-preserving, and give a survey of existing work including the system architecture, location anonymity and query processing.

  10. Crack - seal veins - what we learnt since the seminal work of John Ramsay

    Science.gov (United States)

    Urai, Janos L.; Bons, Paul D.

    2017-04-01

    In the nineteen-eighties, John Ramsay and co-workers have laid the basis for much of our current understanding of tectonic veins, by proposing that tectonic veins accrete in many small increments of cracking and sealing, making the link to cyclic stress and fluid pressure cycles and the earthquake cycle, and by proposing that fibrous veins track the opening trajectory, which has created a toolbox to analyse progressive deformation in rocks. They recognised syntaxial and antitaxial veins, which grow depending on the composition of the wall rock and the vein. Following on these seminal contributions, advances in analysing the microstructure and chemical signature in crack-seal veins made a lot of progress, facilitated by the rapid increase in micro analytical tools like cathodeluminescence and EBSD. Initial modelling of crystal growth in crack- seal veins provided an explanation of how crystals become fibrous without being deformed and explained how fibres sometimes do and sometimes don't follow the opening trajectory. This was followed by numerical models of crystal growth to study the development of crystal facets after larger crack increments, and experimental study of the sealing dynamics of syntaxial veins. These models were initially kinematic, using the ELLE microdynamic simulation package, and more recently incorporating the physics of the growing interface using the Phase Field method, which now allows 3D simulation of both syntaxial and antitaxial veins and can simultaneously compute the evolving permeability of the crack using Lattice Boltzmann techniques. Parallel to these developments we developed an understanding of the strength of the vein cement, and, using Discrete Element Techniques, explored the effects of differences of the strength of the vein and its adhesion to the wall rock on fracture patterns in crack-seal systems in changing stress fields. This presentation will review these developments, showing how the ideas of John Ramsay inspired follow

  11. Crystal field analysis of Pm$^{3+}$ (4$^{f4}) and Sm$^{3+}$ (4$^{f5}) and lattice location studies of $^{147}$Nd and $^{147}$Pm in w-AlN

    CERN Document Server

    Vetter, Ulrich; Nijjar, Anmol S; Zandi, Bahram; Öhl, Gregor; Wahl, Ulrich; De Vries, Bart; Hofsäss, Hans; Dietrich, Marc

    2006-01-01

    We report a detailed crystal field analysis of Pm3+ and Sm3+ as well as lattice location studies of 147Pm and 147Nd in 2H-aluminum nitride (w-AlN). The isotopes of mass 147 were produced by nuclear fission and implanted at an energy of 60 keV. The decay chain of interest in this work is 147Nd→147Pm→147Sm (stable). Lattice location studies applying the emission channeling technique were carried out using the β− particles and conversion electrons emitted in the radioactive decay of 147Nd→147Pm. The samples were investigated as implanted, and also they were investigated after annealing to temperatures of 873 K as well as 1373 K. The main fraction of about 60% of both 147Pm as well as 147Nd atoms was located on substitutional Al sites in the AlN lattice; the remainder of the ions were located randomly within the AlN lattice. Following radioactive decay of 147Nd, the cathodoluminescence spectra of Pm3+ and Sm3+ were obtained between 500 nm and 1050 nm at sample temperatures between 12 K and 300 K. High-re...

  12. Minimally invasive treatments for perforator vein insufficiency.

    Science.gov (United States)

    Kuyumcu, Gokhan; Salazar, Gloria Maria; Prabhakar, Anand M; Ganguli, Suvranu

    2016-12-01

    Incompetent superficial veins are the most common cause of lower extremity superficial venous reflux and varicose veins; however, incompetent or insufficient perforator veins are the most common cause of recurrent varicose veins after treatment, often unrecognized. Perforator vein insufficiency can result in pain, skin changes, and skin ulcers, and often merit intervention. Minimally invasive treatments have replaced traditional surgical treatments for incompetent perforator veins. Current minimally invasive treatment options include ultrasound guided sclerotherapy (USGS) and endovascular thermal ablation (EVTA) with either laser or radiofrequency energy sources. Advantages and disadvantages of each modality and knowledge on these treatments are required to adequately address perforator venous disease.

  13. Apoptosis-inducing effect and intracellular location of Vibrio vulnificus cytolysin to human umbilical vein endothelial cell in vitro%创伤弧菌溶细胞素体外诱导人脐静脉内皮细胞凋亡及其在细胞中的定位

    Institute of Scientific and Technical Information of China (English)

    赵金方; 丁威; 赵旭鸿; 陆淼泉; 严杰

    2008-01-01

    Objective To determine the effect of Vibrio vulnificus cytolysin (VVC) inducing ap-optosis in human umbilical vein endothelial cell(HUVEC) and its possible mechanism. Methods The en-tire vvhA gene that encoding VVC from V. vulnificus strain GTC333 was amplified by PCR and sequenced af-ter T-A cloning. E. coli BL21DE3pET-42a-vvhA, a prokaryotic expression system of the vvhA gene, was then con-structed. Ni-NTA affinity chromatography was applied to purify the target recombinant protein rVVC, and SDS-PAGE plus Bio-Rad Agarose Image Analyzor were used to measure the output of rVVC and to determine the purity of rVVC extract. The activity of rVVC dissolving rabbit erythrocytes was detected by hemolysis test. DPNH chromotometry and TphBNa chromotometry were performed to examine the contents of LDH and K+ in the supernatants of rVVC-treated HUVEC cultures, respectively. The effect of rVVC inducing apepto-sis of HUVEC was detected by flow cytometry, rVVC was labeled with FITC and the location of FITC-labe-ling rVVC in HUVEC was observed by laser canfocal microscopy. Results The cloned whA gene had 96.09% and 98.26% similarities of nucleotide and amino acid sequences compared to the corresponding se-quences in GenBank. rVVC, with a dosage of 1 μg/ml, could dissolve rabbit erythrocytes (P0.05).1~100μg/ml的rVVC作用2 h可使HUVEC凋亡.在FITC标记rVVC作用HUVEC 5~240 min内,rVVC逐渐从细胞膜表面向膜内侧和胞浆内移行,作用30 min时多数rVVC进入细胞.结论 rVVC具有溶细胞素活性.VVC可进入HUVEC,诱导细胞凋亡是其损伤HUVEC的主要机制.

  14. Extrahepatic Portal Vein Obstruction and Portal Vein Thrombosis in Special Situations: Need for a New Classification

    Science.gov (United States)

    Wani, Zeeshan A.; Bhat, Riyaz A.; Bhadoria, Ajeet S.; Maiwall, Rakhi

    2015-01-01

    Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized. PMID:26021771

  15. Extrahepatic portal vein obstruction and portal vein thrombosis in special situations: Need for a new classification

    Directory of Open Access Journals (Sweden)

    Zeeshan A Wani

    2015-01-01

    Full Text Available Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized.

  16. Library Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Carnegie Library of Pittsburgh locations including address, coordinates, phone number, square footage, and standard operating hours.

  17. Colloidal gold and silica in mesothermal vein systems

    Science.gov (United States)

    Herrington, R. J.; Wilkinson, J. J.

    1993-06-01

    Some of the textural features of mesothermal gold-quartz veins may be best explained by the initial precipitation of amorphous silica gel (colloid), which subsequently crystallizes to quartz. This can occur in brittle-ductile shear zones where a significant fluid-pressure drop occurs during stick-slip failure. Such a process rapidly supersaturates the hydrothermal fluid with respect to amorphous silica, which precipitates instead of quartz, owing to favorable kinetics. Depressurization also commonly leads to fluid unmixing and destabilization of soluble gold complexes. However, the presence of colloidal silica can stabilize gold colloid, allowing further transport of particulate gold in suspension in the hydrothermal fluid. Silica gel would be highly unstable under mesothermal conditions and would undergo rapid syneresis and crystallization to form quartz; solid impurities would tend to be expelled toward grain boundaries. This model can account for the primary anhedral aggregate textures typical of mesothermal quartz veins, the concentration of gold along grain boundaries and the formation of discrete gold nuggets, and the rare occurrence of low-order silica polymorphs and relict spheroidal structures. The transport of gold in colloidal form may be one reason for the frequently consistent bulk grade distribution in gold-quartz vein systems over many hundreds of metres (in some cases kilometres) of depth. In addition, the formation of charged colloidal particles may help to explain the attraction of gold grains to specific mineral surfaces.

  18. Angiosarcoma of common iliac vein

    Science.gov (United States)

    Ibis, Kamuran; Usta, Ufuk; Cosar, Rusen; Ibis, Cem

    2015-01-01

    Angiosarcoma is a rare malignant tumour of endothelial cells. Primary angiosarcoma of venous origin is extremely rare, and has a very poor prognosis. A 63-year-old woman with retroperitoneal mass underwent en bloc resection on a part of iliac vein followed by adjuvant radiotherapy. No recurrence was detected during 3 years of follow-up. PMID:25596292

  19. Clinical studies on inferior right hepatic veins

    Institute of Scientific and Technical Information of China (English)

    Xue Xing; Hong Li; Wei-Guo Liu

    2007-01-01

    BACKGROUND:Many small veins are called accessory, short hepatic veins in addition to the right, middle and left hepatic veins. The size of these veins varied from a pinhole to 1 cm; the size of inferior right hepatic veins (IRHVs) is thicker than that of short hepatic veins or more than 1 cm occasionally. Adults have a higher incidence rate of the IRHV. DATA SOURCES:A literature search of the PubMed database was conducted and research articles were reviewed. RESULTS:The size of IRHVs is related to the size of the right hepatic vein, i.e. the larger the diameter of the right hepatic vein, the smaller the diameter of the IRHVs, and vice versa. The IRHVs are divided into superior, medial and inferior groups, separately named the superior, medial and inferior right hepatic veins according to the position of the IRHV entering the inferior vena cava. The superior right hepatic vein mainly drains the superior part of segmentⅦ, and the medial right hepatic vein drains the middle part of segmentⅦ. A thicker IRHV mainly drains segmentⅥ and the inferior part of segmentⅦ and a thinner IRHV drains the inferior part of segmentⅤ. CONCLUSIONS:The clinical signiifcance of these studies on IRHVs is varied: (1) Hepatic caudate lobe resection could be introduced after study on the veins of that lobe. (2) It is very important to identify the draining region of the IRHV for guiding hepatic segmentectomy. The postero-inferior area of the right lobe can be preserved along with the hypertrophic IRHV even if the entire main right hepatic vein is resected during segmentectomy ofⅦ andⅧwith right hepatic vein resection for patients with primary liver cancer. (3) The ligation of the major hepatic vein for the treatment of juxtahepatic vein injury is recommended because of severe hemorrhagic shock and dififculty in

  20. Common femoral vein reconstruction using internal jugular vein after blast injury.

    Science.gov (United States)

    Holt, Andrew M; West, Charles A; Davis, James A; Gilani, Ramyar; Askenasy, Eric

    2014-10-01

    Common femoral vein traumatic injuries are rare. Surgical management is controversial and by nature case specific. In this report, we present an unusual case of an isolated common femoral vein injury from a gunshot blast repaired with an interposition internal jugular vein bypass. To our knowledge, this is the first reported case of an isolated common femoral vein reconstructed in this manner.

  1. Mineral vein dynamics modelling (FRACS II)

    Energy Technology Data Exchange (ETDEWEB)

    Urai, J.; Virgo, S.; Arndt, M. [RWTH Aachen (Germany); and others

    2016-08-15

    The Mineral Vein Dynamics Modeling group ''FRACS'' started out as a team of 7 research groups in its first phase and continued with a team of 5 research groups at the Universities of Aachen, Tuebingen, Karlsruhe, Mainz and Glasgow during its second phase ''FRACS 11''. The aim of the group was to develop an advanced understanding of the interplay between fracturing, fluid flow and fracture healing with a special emphasis on the comparison of field data and numerical models. Field areas comprised the Oman mountains in Oman (which where already studied in detail in the first phase), a siliciclastic sequence in the Internal Ligurian Units in Italy (closed to Sestri Levante) and cores of Zechstein carbonates from a Lean Gas reservoir in Northern Germany. Numerical models of fracturing, sealing and interaction with fluid that were developed in phase I where expanded in phase 11. They were used to model small scale fracture healing by crystal growth and the resulting influence on flow, medium scale fracture healing and its influence on successive fracturing and healing, as well as large scale dynamic fluid flow through opening and closing fractures and channels as a function of fluid overpressure. The numerical models were compared with structures in the field and we were able to identify first proxies for mechanical vein-hostrock properties and fluid overpressures versus tectonic stresses. Finally we propose a new classification of stylolites based on numerical models and observations in the Zechstein cores and continued to develop a new stress inversion tool to use stylolites to estimate depth of their formation.

  2. Who Is at Risk for Varicose Veins?

    Science.gov (United States)

    ... may raise your risk for varicose veins. The normal wear and tear of aging may cause the valves in your veins to weaken and not work well. Gender Women tend to get varicose veins more often than men. Hormonal changes that occur during puberty, pregnancy, and menopause (or ...

  3. Cephalic veins in coronary artery bypass surgery

    DEFF Research Database (Denmark)

    Licht, P; Jakobsen, Erik; Lerbjerg, G

    1996-01-01

    Various alternative conduits for aortocoronary bypass grafting have been suggested when the saphenous vein quality is inadequate. During a 10-year period we have used the cephalic vein in 39 patients. Eighteen entered an angiographic follow-up study. A total of 31 arm vein grafts were used with 4...

  4. Radiological aspects of portal vein embolization

    NARCIS (Netherlands)

    van Lienden, K.P.

    2012-01-01

    This thesis deals with liver regeneration after portal vein embolization (PVE) or portal vein ligation (PVL). Several aspects of these portal vein occlusion techniques are evaluated in clinical and experimental studies. In addition, the role of dynamic liver function tests and CT-volumetry in risk a

  5. Cephalic veins in coronary artery bypass surgery

    DEFF Research Database (Denmark)

    Licht, P; Jakobsen, Erik; Lerbjerg, G;

    1996-01-01

    Various alternative conduits for aortocoronary bypass grafting have been suggested when the saphenous vein quality is inadequate. During a 10-year period we have used the cephalic vein in 39 patients. Eighteen entered an angiographic follow-up study. A total of 31 arm vein grafts were used with 4...

  6. A New Multimodal Biometric System Based on Finger Vein and Hand Vein Recognition

    OpenAIRE

    Randa Boukhris Trabelsi; Alima Damak Masmoudi; Dorra Sellami Masmoudi

    2013-01-01

    As a reliable and robust biological characteristic, the vein pattern increases more and more the progress in biometric researches. Generally, it was shown that single biometric modality recognition is not able to meet high performances. In this paper, we propose a new multimodal biometric system based on fusion of both hand vein and finger vein modalities. For finger vein recognition, we employ the Monogenic Local Binary Pattern (MLBP), and for hand vein recognitionan Improved Gaussian Matche...

  7. Recurrence of superficial vein thrombosis in patients with varicose veins.

    Science.gov (United States)

    Karathanos, Christos; Spanos, Konstantinos; Saleptsis, Vassileios; Tsezou, Aspasia; Kyriakou, Despina; Giannoukas, Athanasios D

    2016-08-01

    To investigate which factors other than history of superficial vein thrombosis (SVT) are associated with recurrent spontaneous SVT episodes in patients with varicose veins (VVs). Patients with a history of spontaneous SVT and VVs were followed up for a mean period of 55 months. Demographics, comorbidities, and thrombophilia screening test were analyzed. Patients were grouped according to the clinical-etiology-anatomy-pathophysiology classification. A multiple logistic regression analysis with the forward likelihood ratio method was undertaken. Thirteen patients out of 97 had a recurrence SVT episode during the follow-up period. All those patients were identified to have a thrombophilia defect. Protein C and S, antithrombin, and plasminogen deficiencies were more frequently present in patients without recurrence. Gene mutations were present in 38% in the nonrecurrence group and 77% in the recurrence group. After logistic regression analysis, patients with dislipidemia and mutation in prothrombin G20210A (FII) had an increased risk for recurrence by 5.4-fold and 4.6-fold, respectively. No deep vein thrombosis or pulmonary embolism occurred. Dislipidemia and gene mutations of F II are associated with SVT recurrence in patients with VVs. A selection of patients may benefit from anticoagulation in the short term and from VVs intervention in the long term. © The Author(s) 2015.

  8. Local SIFT analysis for hand vein pattern verification

    Science.gov (United States)

    Wang, Yunxin; Wang, Dayong; Liu, Tiegen; Li, Xiuyan

    2009-11-01

    The newly emerging hand vein recognition technology has attracted remarkable attention for its uniqueness, noninvasion, friendliness and high reliability. It is unavoidable to produce small location deviation of human hand in the practical application; however, the existing recognition methods are sensitive to the hand shift or rotation. The test sample is matched with a series of registered images after affine transformation including the shift or rotation by most of researches, this affine transform method can remedy the location deviation to some extent, but the limited range for hand shift and rotation brings users much inconvenience and the computational cost also increases greatly. Aiming at this issue, a hand vein recognition algorithm based on local SIFT (Scale Invariant Feature Transform) analysis is developed in this contribution, which has practical significance due to its translation and rotation invariance. First, the hand vein image is preprocessed to remove the background and reduce image noises, and then SIFT features are extracted to describe the gradient information of hand vein. Many one-to-more matching pairs are produced by the common matching method of SIFT features, thus the matching rule is improved by appending a constrained condition to ensure the one-to-one matching, which is achieved by selecting feature point with the nearest distance as the optimal match. Finally the match ratio of features between the registered and test images is calculated as the similarity measurement to verify the personal identification. The experiment results show that FRR (False Rejection Rate) is only 0.93% when FAR (False Acceptance Rate) is 0.002%, and EER (Equal Error Rate) is low to 0.12%, which demonstrate the proposed approach is valid and effective for hand vein authentication.

  9. Management of varicose veins and venous insufficiency.

    Science.gov (United States)

    Hamdan, Allen

    2012-12-26

    Chronic venous disease, reviewed herein, is manifested by a spectrum of signs and symptoms, including cosmetic spider veins, asymptomatic varicosities, large painful varicose veins, edema, hyperpigmentation and lipodermatosclerosis of skin, and ulceration. However, there is no definitive stepwise progression from spider veins to ulcers and, in fact, severe skin complications of varicose veins, even when extensive, are not guaranteed. Treatment options range from conservative (eg, medications, compression stockings, lifestyle changes) to minimally invasive (eg, sclerotherapy or endoluminal ablation), invasive (surgical techniques), and hybrid (combination of ≥1 therapies). Ms L, a 68-year-old woman with varicose veins, is presented. She has had vein problems over the course of her life. Her varicose veins recurred after initial treatment, and she is now seeking guidance regarding her current treatment options.

  10. [ENDOVENOUS LASER TREATMENT FOR VARICOSE VEINS].

    Science.gov (United States)

    Tezuka, Masahiro; Kanaoka, Yuji; Ohki, Takao

    2015-05-01

    Varicose veins are a common condition attecting approximately 10 million patients in Japan. The main cause of varicose veins is reflux of the saphenous vein, and conventional treatment for several decades was stripping the affected saphenous vein and phlebectomy. Endovenous laser treatment (EVLT) is a less-invasive treatment method in which the saphenous vein is ablated with a laser under local anesthesia. EVLT has been approved by the Japanese Ministry of Health, Labor and Welfare since 2011, and we have performed EVLT on 5,160 legs with saphenous insufficiency with no severe complications including deep vein thrombosis except for one case of arteriovenous fistula. EVLT appears to be a safe, effective treatment option for varicose veins with saphenous insufficiency.

  11. Deep vein thrombosis in pregnancy.

    Science.gov (United States)

    Colman-Brochu, Stephanie

    2004-01-01

    This article provides a review of the incidence, pathophysiology, and treatment of deep vein thrombosis (DVT) in pregnancy, a rare but serious complication of pregnancy. The incidence of DVT in pregnancy varies widely, but it is a leading cause of maternal morbidity in both the United States and the United Kingdom. Risk factors during pregnancy include prolonged bed rest or immobility, pelvic or leg trauma, and obesity. Additional risk factors are preeclampsia, Cesarean section, instrument-assisted delivery, hemorrhage, multiparity, varicose veins, a previous history of a thromboembolic event, and hereditary or acquired thrombophilias such as Factor V Leiden. Heparin is the anticoagulant of choice to treat active thromboembolic disease or to administer for thromboprophylaxis, but low molecular-weight heparin is being used with increasing frequency in the pregnant woman. Perinatal nurses should be aware of the symptoms, diagnostic tools, and treatment options available to manage active thrombosis during pregnancy and in the intrapartum and postpartum periods.

  12. FINGER-VEIN RECOGNITION SYSTEMS

    Directory of Open Access Journals (Sweden)

    A.Haritha Deepthi

    2015-10-01

    Full Text Available As the Person‟s/Organization‟s Private information‟s are becoming very easy to access, the demand for a Simple, Convenient, Efficient, and a highly Securable Authentication System has been increased. In considering these requirements for data Protection, Biometrics, which uses human physiological or behavioral system for personal Identification has been found as a solution for these difficulties. However most of the biometric systems have high complexity in both time and space. So we are going to use a Real time Finger-Vein recognition System for authentication purposes. In this paper we had implemented the Finger Vein Recognition concept using MATLAB R2013a. The features used are Lacunarity Distance, Blanket Dimension distance. This has more accuracy when compared to conventional methods.

  13. Mortality after portal vein embolization

    Science.gov (United States)

    Lee, Eung Chang; Park, Sang-Jae; Han, Sung-Sik; Park, Hyeong Min; Lee, Seung Duk; Kim, Seong Hoon; Lee, In Joon; Kim, Hyun Beom

    2017-01-01

    Abstract Portal vein embolization (PVE) is increasingly performed worldwide to reduce the possibility of liver failure after extended hepatectomy, by inducing future liver remnant (FLR) hypertrophy and atrophy of the liver planned for resection. The procedure is known to be very safe and to have few procedure-related complications. In this study, we described 2 elderly patients with Bismuth–Corlette type IV Klatskin tumor who underwent right trisectional PVE involving the embolization of the right portal vein, the left medial sectional portal branch, and caudate portal vein. Within 1 week after PVE, patients went into sepsis combined with bile leak and died within 1 month. Sepsis can cause acute liver failure in patients with chronic liver disease. In this study, the common patient characteristics other than sepsis, that is, trisectional PVE; chronic alcoholism; aged >65 years; heart-related comorbidity; and elevated serum total bilirubin (TB) level (7.0 mg/dL) at the time of the PVE procedure in 1 patient, and concurrent biliary procedure, that is, percutaneous transhepatic biliary drainage in the other patient might have affected the outcomes of PVE. These cases highlight that PVE is not a safe procedure. Care should be taken to minimize the occurrence of infectious events because sepsis following PVE can cause acute liver failure. Additionally, prior to performing PVE, the extent of PVE, chronic alcohol consumption, age, comorbidity, long-lasting jaundice, concurrent biliary procedure, etc. should be considered for patient safety. PMID:28178122

  14. Using vein fabric and fluid inclusion characteristics as an integrated proxy to constrain the relative timing of non cross-cutting, syn- to late-orogenic quartz vein generations

    Science.gov (United States)

    Jacques, Dominique; Muchez, Philippe; Sintubin, Manuel

    2014-05-01

    Research on ancient fluid systems mainly focuses on veins, because they offer the opportunity to combine macro- and microstructural data with geochemical data to gain insight into the P-T-X conditions present during veining. By applying such an integrated petrographic and microthermometric methodology to syn- to late-orogenic quartz veins in the Palaeozoic High-Ardenne slate belt (Belgium), we were able to define the relative timing and related P-T-X conditions of different quartz vein generations, despite of the absence of any mutual cross-cutting relationships in the field (Jacques et al., 2014). The different quartz vein generations represent the meso-scale brittle accommodation during fold initiation, amplification and locking. The presence of free polycrystal growth in cavities at a midcrustal depth, and fluid-assisted brecciation indicate that veining occurred under overpressured fluid conditions during the orogeny. Significant differences in crystal-plastic deformation microstructures and P-T trapping conditions indicate that the different processes accommodating folding occurred in a progressive manner along a retrograde deformation path. While vein quartz in an extrados vein and in the peripheral part of a lenticular, fault-accommodating vein shows moderate crystal-plastic deformation (e.g. bulging recrystallisation, deformation lamellae, shear bands), crystal-plastic deformation is relatively absent in the vein quartz of a saddle reef and the core of the lenticular vein (i.e. no to minor undulose extinction). Successive veining occurred from peak metamorphic conditions (ca. 300 ° C and 190 MPa), measured in the extrados vein, to lower P-T conditions in the periphery of the lenticular vein (ca. 275 ° C and 180 MPa), the late-orogenic saddle reef (ca. 245 ° C and 160 MPa) and the core of the lenticular vein (ca. 220 ° C and 150 MPa). The relative timing and accompanying decrease in P-T conditions of the different quartz vein generations reflect the

  15. Undivided Retromandibular Vein Continuing As External Jugular Vein With Facial Vein Draining Into It : An Anatomical Variation

    Directory of Open Access Journals (Sweden)

    Shahnaz Choudhary, Ashwani K Sharma, Harbans Singh

    2010-10-01

    Full Text Available Despite the fact that the blueprint of the whole body is unravelled, faultlessly during the growth anddevelopment of an animal; but amazingly variations do occur. During routine dissection of head and neckin a middle aged cadaver in the Post Graduate Department of Anatomy of this medical college, we foundvariation in the formation of external jugular vein on both sides, which was formed by the continuation ofundivided trunk of retromandibular vein. The facial vein and posterior auricular vein were the tributaries ofexternal jugular vein. The sound anatomical knowledge of variations of the veins of head and neck isessential to the success of surgical procedures. The embryological evaluation of the above anomaly wasdone and compared with the available literature which showed that the observed variation was rare

  16. The umbilical and paraumbilical veins of man.

    Science.gov (United States)

    Martin, B F; Tudor, R G

    1980-03-01

    During its transit through the umbilicus structural changes occur in the thick wall of the extra-abdominal segment of the umbilical vein whereby the components of the intra-abdominal segment acquire an essentially longitudinal direction and become arranged in fibro-elastic and fibro-muscular zones. The vein lumen becomes largely obliterated by asymmetrical proliferation of loose subendothelial conective tissue. The latter forms a new inner zone within which a small segment of the lumen persists in an eccentric position. This residual lumen transmits blood to the portal system from paraumbilical and systemic sources, and is retained in the upper part of the vein, even in old age. A similar process of lumen closure is observed in the ductus venosus. In early childhood the lower third of the vein undergoes breakdown, with fatty infiltration, resulting in its complete division into vascular fibro-elastic strands, and in old age some breakdown occurs in the outermost part of the wall of the upper two thirds. The paraumbilical veins are thick-walled and of similar structure to the umbilical vein. Together they constitute an accessory portal system which is confined between the layers of the falciform ligament and is in communication with the veins of the ventral abdominal wall. The constituents form an ascending series, namely, Burow's veins, the umbilical vein, and Sappey's inferior and superior veins. The main channel of Sappey's inferior veins may be the remnant of the right umbilical vein since it communicates with the right rectus sheath and often communicates directly with the portal system within the right lobe of the liver. The results are of significance in relation to clinical usage of the umbilical vein.

  17. Toward an Optimal Position for IVC Filters: Computational Modeling of the Impact of Renal Vein Inflow

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S L; Singer, M A

    2009-07-13

    The purpose of this report is to evaluate the hemodynamic effects of renal vein inflow and filter position on unoccluded and partially occluded IVC filters using three-dimensional computational fluid dynamics. Three-dimensional models of the TrapEase and Gunther Celect IVC filters, spherical thrombi, and an IVC with renal veins were constructed. Hemodynamics of steady-state flow was examined for unoccluded and partially occluded TrapEase and Gunther Celect IVC filters in varying proximity to the renal veins. Flow past the unoccluded filters demonstrated minimal disruption. Natural regions of stagnant/recirculating flow in the IVC are observed superior to the bilateral renal vein inflows, and high flow velocities and elevated shear stresses are observed in the vicinity of renal inflow. Spherical thrombi induce stagnant and/or recirculating flow downstream of the thrombus. Placement of the TrapEase filter in the suprarenal vein position resulted in a large area of low shear stress/stagnant flow within the filter just downstream of thrombus trapped in the upstream trapping position. Filter position with respect to renal vein inflow influences the hemodynamics of filter trapping. Placement of the TrapEase filter in a suprarenal location may be thrombogenic with redundant areas of stagnant/recirculating flow and low shear stress along the caval wall due to the upstream trapping position and the naturally occurring region of stagnant flow from the renal veins. Infrarenal vein placement of IVC filters in a near juxtarenal position with the downstream cone near the renal vein inflow likely confers increased levels of mechanical lysis of trapped thrombi due to increased shear stress from renal vein inflow.

  18. Palm Vein Verification Using Gabor Filter

    Directory of Open Access Journals (Sweden)

    Ali Mohsin Al-Juboori

    2013-01-01

    Full Text Available Palm vein authentication is one of the modern biometric techniques, which employs the vein pattern in the human palm to verify the person. The merits of palm vein on classical biometric (e.g. fingerprint, iris, face are a low risk of falsification, difficulty of duplicated and stability. In this research, a new method is proposed for personal verification based on palm vein features. In the propose method, the palm vein images are firstly enhanced and then the features are extracted by using bank of Gabor filters. Then Fisher Discriminated Analysis (FDA is used to reduce the dimension of the features vectors. For vein pattern verification, this work uses Nearest Neighbors method. The EER of the proposed method is 0.2335%.

  19. Preduodenal portal vein: its surgical significance.

    Science.gov (United States)

    Makey, D A; Bowen, J C

    1978-11-01

    Preduodenal portal vein is a rare anatomical variant which may be one of many anomalies in the neonate with duodenal "atresia." Preduodenal portal vein also may be an occasional finding in an adult undergoing biliary, gastric, or pancreatic surgery. Awareness and recognition of the anomaly are essential for the avoidance of injury during such operations. We report here a symptomless patient whose preduodenal portal vein was discovered at cholecystectomy.

  20. A review of a new Dutch guideline for management of recurrent varicose veins.

    Science.gov (United States)

    Lawson, James A; Toonder, Irwin M

    2016-03-01

    In 2013, the new Dutch guideline for "Venous Pathology" was published. The guideline was a revision and update from the guideline "Diagnostics and Treatment of Varicose Veins" from 2009 and the guideline "Venous Ulcer" from 2005. A guideline for "Deep Venous Pathology" and one for "Compression Therapy" was added to the overall guideline "Venous Pathology." The chapter about treatment of recurrent varicose veins after initial intervention was recently updated in 2015 and is reviewed here. The Dutch term "recidief varices" or the French "récidive de varices" should be used analogous to the English term "recurrent varicose veins." The DCOP Guideline Development Group Neovarices concluded that "recidief" in Dutch actually suggests recurrence after apparent successful treatment and ignores the natural progression of venous disease in its own right. So the group opted to use the term "neovarices." In the Dutch guideline, neovarices is meant to be an all embracing term for recurrent varicose veins caused by technical or tactical failure, evolvement from residual refluxing veins or natural progression of varicose vein disease at different locations of the treated leg after intervention. This report reviews the most important issues in the treatment of varicose vein recurrence, and discusses conclusions and recommendations of the Dutch Neovarices Guideline Committee.

  1. Small hepatic veins Budd-Chiari syndrome.

    Science.gov (United States)

    Riggio, Oliviero; Marzano, Chiara; Papa, Alessia; Pasquale, Chiara; Gasperini, Maria Ludovica; Gigante, Antonietta; Valla, Dominique Charles; Plessier, Aurélie; Amoroso, Antonio

    2014-05-01

    Budd-Chiari syndrome is a rare disorder characterized by hepatic venous outflow obstruction at any level from the small hepatic veins to the atrio-caval junction, in the absence of heart failure or constrictive pericarditis. Various imaging modalities are available for investigating the gross hepatic vascular anatomy but there are rare forms of this disease where the obstruction is limited to the small intrahepatic veins, with normal appearance of the large hepatic veins at imaging. In this cases only a liver biopsy can demonstrate the presence of a small vessels outflow block. We report two cases of small hepatic veins Budd-Chiari syndrome.

  2. Leiomyosarcoma of the external iliac vein.

    Science.gov (United States)

    Fukuda, Wakako; Taniguchi, Satoshi; Fukuda, Ikuo

    2012-06-01

    Leiomyosarcoma of the iliac vein is an uncommon tumor. We report a case of a 63-year-old Japanese woman with leiomyosarcoma of the right external iliac vein. The patient complained of right inguinal pain and swelling. Computed tomography demonstrated a mass surrounding the right external iliac artery and vein. Metastases in the lungs and liver were found. Complete resection of the tumor along with the involved vessels was performed. Polytetrafluoroethylene grafts were used to reconstruct the vessels. Pathological examination revealed leiomyosarcoma of the external iliac vein. Although the prognosis of leiomyosarcoma is poor, en bloc tumor resection is the treatment of choice.

  3. Sonographic Findings in Fetal Renal Vein Thrombosis.

    Science.gov (United States)

    Gerber, Rebecca E; Bromley, Bryann; Benson, Carol B; Frates, Mary C

    2015-08-01

    We present the sonographic findings of fetal renal vein thrombosis in a series of 6 patients. The mean gestational age at diagnosis was 31.2 weeks. Four cases were unilateral, and 2 were bilateral. The most common findings were renal enlargement and intrarenal vascular calcifications, followed by increased renal parenchymal echogenicity. Inferior vena cava thrombosis was found in 4 patients and common iliac vein thrombosis in 2. Fetal renal vein thrombosis is an uncommon diagnosis with characteristic sonographic findings. The presence of these findings should prompt Doppler interrogation of the renal vein and inferior vena cava to confirm the diagnosis.

  4. Brittle–viscous deformation of vein quartz under fluid-rich low greenschist facies conditions

    Directory of Open Access Journals (Sweden)

    H. J. Kjøll

    2015-01-01

    Full Text Available A coarse grained, statically crystallized quartz vein, embedded in a phyllonitic matrix, was studied by EBSD and optical microscopy to gain insights into the processes of strain localization in quartz deformed under low-grade conditions, broadly coincident with the frictional–viscous transition. The vein is from a high strain zone at the front of the Porsa Imbricate Stack in the Paleoproterozoic Repparfjord Tectonic Window in northern Norway. The vein was deformed under lower greenschist facies conditions during deformation along a large out-of-sequence phyllonitic thrust of Caledonian age. The host phyllonite formed at the expense of metabasalt wherein feldspar broke down to form interconnected layers of fine, synkinematic phyllosilicates. In the mechanically weak framework of the phyllonite, the studied quartz vein acted as a relatively rigid body deforming mainly by coaxial strain. Viscous deformation was initially accommodated by basal ⟨a⟩ slip of quartz during the development of a mesoscopic pervasive extensional crenulation cleavage. Under the prevailing boundary conditions, however, dislocation glide-accommodated deformation of quartz resulted inefficient and led to dislocation tangling and strain hardening of the vein. In response to hardening, to the progressive increase of fluid pressure and the increasing competence contrast between the vein and the weak foliated host phyllonite, quartz crystals began to deform frictionally along specific, optimally oriented lattice planes, creating microgouges along microfractures. These were, however, rapidly sealed by nucleation of new grains as transiently over pressured fluids penetrated the deforming system. The new nucleated grains grew initially by solution-precipitation and later by grain boundary migration. Due to the random initial orientation of the vein crystals, strain was accommodated differently in the individual crystals, leading to the development of remarkably different

  5. phenoVein - A tool for leaf vein segmentation and analysis

    OpenAIRE

    Bühler, J.; Rishmawi, L.; Pflugfelder, D.; Huber, G; Scharr, H.; Hülskamp, M; Koornneef, M.; Schurr, U; Jahnke, S.

    2015-01-01

    Precise measurements of leaf vein traits are an important aspect of plant phenotyping for ecological and genetic research. Here, we present a powerful and user-friendly image analysis tool named phenoVein. It is dedicated to automated segmenting and analyzing of leaf veins in images acquired with different imaging modalities (microscope, macrophotography, etc.), including options for comfortable manual correction. Advanced image filtering emphasizes veins from the background and compensates f...

  6. Subclavian vein aneurysm secondary to a benign vessel wall hamartoma

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Patrick [Nationwide Children' s Hospital, Section of Pediatric Interventional Radiology, Columbus, OH (United States); Spaeth, Maya [Nationwide Children' s Hospital, Section of Plastic and Reconstructive Surgery, Columbus, OH (United States); Prasad, Vinay [Nationwide Children' s Hospital, Section of Pediatric Pathology, Columbus, OH (United States); McConnell, Patrick [Nationwide Children' s Hospital, Section of Cardiothoracic Surgery, Columbus, OH (United States)

    2013-11-15

    Venous aneurysms are rare clinical entities, particularly in children, and their presentation and natural history often depend on the anatomical location and underlying etiology. We present a single case of a 12-year-old girl who presented with a palpable right supraclavicular mass. Imaging evaluation with CT, conventional venography, MRI and sonography revealed a large fusiform subclavian vein aneurysm with an unusual, mass-like fibrofatty component incorporated into the vessel wall. The girl ultimately required complete resection of the right subclavian vein with placement of a synthetic interposition graft. This case provides a radiology/pathology correlation of an entity that has not previously been described as well as an example of the utility of multiple imaging modalities to aid diagnosis and preoperative planning. (orig.)

  7. Subclavian vein aneurysm secondary to a benign vessel wall hamartoma.

    Science.gov (United States)

    Warren, Patrick; Spaeth, Maya; Prasad, Vinay; McConnell, Patrick

    2013-11-01

    Venous aneurysms are rare clinical entities, particularly in children, and their presentation and natural history often depend on the anatomical location and underlying etiology. We present a single case of a 12-year-old girl who presented with a palpable right supraclavicular mass. Imaging evaluation with CT, conventional venography, MRI and sonography revealed a large fusiform subclavian vein aneurysm with an unusual, mass-like fibrofatty component incorporated into the vessel wall. The girl ultimately required complete resection of the right subclavian vein with placement of a synthetic interposition graft. This case provides a radiology/pathology correlation of an entity that has not previously been described as well as an example of the utility of multiple imaging modalities to aid diagnosis and preoperative planning.

  8. Subclavian artery to internal jugular vein fistula following percutaneous internal jugular vein catheterization.

    Science.gov (United States)

    Merino-Angulo, J; Cortazar, J L; Saez-Garmendia, F; Montejo, M

    1984-01-01

    The percutaneous internal jugular vein approach is now a commonly performed procedure for central venous catheterization. Iatrogenic arteriovenous fistulae are a very infrequent complication. We report an asymptomatic subclavian artery to internal jugular vein fistula following two percutaneous internal jugular vein catheterization attempts.

  9. Transfected Early Growth Response Gene-1 DNA Enzyme Prevents Stenosis and Occlusion of Autogenous Vein Graft In Vivo

    Directory of Open Access Journals (Sweden)

    Chengwei Liu

    2013-01-01

    Full Text Available The aim of this study was to detect the inhibitory action of the early growth response gene-1 DNA enzyme (EDRz as a carrying agent by liposomes on vascular smooth muscle cell proliferation and intimal hyperplasia. An autogenous vein graft model was established. EDRz was transfected to the graft vein. The vein graft samples were obtained on each time point after surgery. The expression of the EDRz transfected in the vein graft was detected using a fluorescent microscope. Early growth response gene-1 (Egr-1 mRNA was measured using reverse transcription-PCR and in situ hybridization. And the protein expression of Egr-1 was detected by using western blot and immunohistochemistry analyses. EDRz was located at the media of the vein graft from 2 to 24 h, 7 h after grafting. The Egr-1 protein was mainly located in the medial VSMCs, monocytes, and endothelium cells during the early phase of the vein graft. The degree of VSMC proliferation and thickness of intima were obviously relieved compared with the no-gene therapy group. EDRz can reduce Egr-1 expression in autogenous vein grafts, effectively restrain VSMC proliferation and intimal hyperplasia, and prevent vascular stenosis and occlusion after vein graft.

  10. Leaf vein length per unit area is not intrinsically dependent on image magnification: avoiding measurement artifacts for accuracy and precision.

    Science.gov (United States)

    Sack, Lawren; Caringella, Marissa; Scoffoni, Christine; Mason, Chase; Rawls, Michael; Markesteijn, Lars; Poorter, Lourens

    2014-10-01

    Leaf vein length per unit leaf area (VLA; also known as vein density) is an important determinant of water and sugar transport, photosynthetic function, and biomechanical support. A range of software methods are in use to visualize and measure vein systems in cleared leaf images; typically, users locate veins by digital tracing, but recent articles introduced software by which users can locate veins using thresholding (i.e. based on the contrasting of veins in the image). Based on the use of this method, a recent study argued against the existence of a fixed VLA value for a given leaf, proposing instead that VLA increases with the magnification of the image due to intrinsic properties of the vein system, and recommended that future measurements use a common, low image magnification for measurements. We tested these claims with new measurements using the software LEAFGUI in comparison with digital tracing using ImageJ software. We found that the apparent increase of VLA with magnification was an artifact of (1) using low-quality and low-magnification images and (2) errors in the algorithms of LEAFGUI. Given the use of images of sufficient magnification and quality, and analysis with error-free software, the VLA can be measured precisely and accurately. These findings point to important principles for improving the quantity and quality of important information gathered from leaf vein systems.

  11. The sentinel vein: an important reference point for surgery in the temporal region.

    Science.gov (United States)

    Trinei, F A; Januszkiewicz, J; Nahai, F

    1998-01-01

    An intimate knowledge of the anatomy of the face is essential to the aesthetic surgeon. It is this knowledge that ultimately improves results and minimizes complications. The major morbidity associated with brow lifts is trauma to the temporal branch of the facial nerve. The general course of this nerve has been well documented, but exact details are still lacking. This anatomic study was designed to further elucidate its path. Dissections were performed on each side of 10 fresh cadaver heads. These dissections revealed a consistent relationship between the temporal branch of the facial nerve and the sentinel vein. The sentinel vein is reliably located and preoperatively easily defines the "zone of caution", enabling the surgeon to operate rapidly and with confidence until the zone is reached, at which time the dissection is slower as the vein is approached. In the patient in whom the sentinel vein is not easily visualized externally, it may be identified through fixed skeletal landmarks.

  12. Renal infarction in a patient with pulmonary vein thrombosis after left upper lobectomy.

    Science.gov (United States)

    Manabe, Shun; Oshima, Yasuko; Nakano, Marie; Fujii, Teruhiro; Maehara, Takamitsu; Nitta, Kosaku; Hatano, Michiyasu

    2014-05-01

    A 43-year-old male experienced renal infarction (RI) following left upper lobectomy for lung cancer. The patient complained of acute-onset severe left flank pain on the 14th postoperative day. A contrast-enhanced computed tomography (CT) of the abdomen revealed RI by a large wedge-shaped defect in the left kidney. A chest CT scan located the thrombus in the stump (a blind-ended vessel) of the left superior pulmonary vein. Therefore, thromboembolic RI caused by pulmonary vein thrombosis was suspected. Anticoagulation therapy was initiated with heparin and warfarin to treat RI and to prevent further embolic episodes. Two months later, pulmonary vein thrombosis had resolved without the appearance of additional peripheral infarction. This case emphasizes the need to consider thrombus in the stump of the pulmonary vein as a cause of RI.

  13. Generating and analyzing synthetic finger vein images

    NARCIS (Netherlands)

    Hillerström, Fieke; Kumar, Ajay; Veldhuis, Raymond

    2014-01-01

    Abstract: The finger-vein biometric offers higher degree of security, personal privacy and strong anti-spoofing capabilities than most other biometric modalities employed today. Emerging privacy concerns with the database acquisition and lack of availability of large scale finger-vein database have

  14. PORTAL VEIN THROMBOSIS-ULTRASOUND IMAGING

    Directory of Open Access Journals (Sweden)

    Trajkovska Meri

    2016-07-01

    Full Text Available Portal venous system, apart from the main portal vein, includes its tributaries: superior and inferior mesenteric vein, as well as splenic vein, so the term portal venous thrombosis encompasses a broad spectrum of pathological conditions. Usually, one or more causative factors can be recognized, either local endothelial/ flow disturbances, or systemic inherited /acquired conditions. Portal vein thrombosis can be associated with benign or malignant disorders. Weather we are speaking about acute or chronic thrombosis, the clinical presentation is different. Acute thrombosis can be presented in a wide range, from mild abdominal discomfort to a state of intestinal ischemia and life-threatening infarction. Chronic thrombosis is usually recognized when variceal bleeding or other symptoms of portal hypertension express. Fast and accurate diagnosis sometimes is a life-saving procedure, especially in acute vascular alterations. Recently, due to the improvement of imaging procedures the number of patients with diagnosed portal vein thrombosis is increasingly growing. With a negative predictive value of 98% color Doppler ultrasound is considered as imaging modality of choice in detecting portal vein thrombosis. Based on large studies it is presumed that overall risk of getting portal vein thrombosis during lifetime is 1% in general population, but much bigger 5%-15% in cirrhotic patients. Existence of specific ultrasound criteria, if fulfilled, has ensured that diagnosis of portal vein thrombosis is fast and non-invasive. Procedure is convenient for the patient and healthcare providers, and above all, allows prompt treatment preventing further deterioration.

  15. Endovenous laser therapy for varicose veins

    NARCIS (Netherlands)

    Disselhoff, B.C.V.M.

    2008-01-01

    This thesis describes the technique of endovenous laser ablation and the outcome of various series of patients with varicose veins due to reflux in the great saphenous vein, treated by endovenous laser ablation or cryostripping in a single-centre study. This study has shown clear advantages of endov

  16. Vein of foramen caecum: imaging findings.

    Science.gov (United States)

    Tutar, Onur; Kandemirli, Sedat Giray; Yildirim, Duzgun; Memis, Emine Sebnem; Bakan, Selim

    2016-07-01

    Vein of foramen caecum has been classically described as a vein that connects nasal mucosa to the superior sagittal sinus in classic anatomy textbooks. However, its existence is controversial in literature. Herein, we demonstrated computed tomography and contrast enhanced magnetic resonance imaging findings of a tubular vascular structure extending to nasal mucosa and superior sagittal sinus.

  17. Improving the management of varicose veins.

    Science.gov (United States)

    Onida, Sarah; Lane, Tristan R A; Davies, Alun H

    2013-01-01

    Up to 30% of the UK population are affected by varicose veins. They are a manifestation of increased venous pressure in the lower limb caused by impaired venous return. Primary varicosities result from poor drainage from the superficial to the deep venous system. Secondary varicosities arise as a result of underlying pathology impeding venous drainage, such as deep venous thrombosis or increased intra-abdominal pressure caused by a mass, pregnancy or obesity. Patients with bleeding varicose veins should be referred to a vascular service immediately. Referral is also indicated in the following cases: symptomatic primary or recurrent varicose veins; lower limb skin changes thought to be caused by chronic venous insufficiency; superficial vein thrombosis and suspected venous incompetence; a venous leg ulcer or healed venous leg ulcer. Imaging is crucial in the assessment of the superficial and deep venous system to enable assessment of venous competence. The gold standard imaging technique is colour duplex ultrasonography. Duplex ultrasound should be used to confirm the diagnosis of varicose veins and the extent of truncal reflux, and to plan treatment for patients with suspected primary or recurrent varicose veins. Superficial vein ligation, phlebectomy and stripping have been the mainstay of treatment. In recent years, new techniques have been developed that are minimally invasive, enabling treatment of superficial venous incompetence with reduced morbidity. NICE recommends that endothermal ablation, in the form of radiofrequency or laser treatment, should be offered as treatment for patients with confirmed varicose veins and truncal reflux.

  18. Retinal vein occlusion: pathophysiology and treatment options

    OpenAIRE

    Niral Karia

    2010-01-01

    Niral KariaDepartment of Ophthalmology, Southend Hospital, Prittlewell Chase, Westcliff on Sea, Essex, United KingdomAbstract: This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms.Keywords: central, hemispheric, branch, retinal vein occlusion, visual loss

  19. Assessment and management of patients with varicose veins.

    Science.gov (United States)

    Allen, Louise

    Varicose veins are enlarged superficial veins found in the legs. This article explores the anatomy and physiology of the venous system to assist nurses to assess, manage and treat patients with varicose veins.

  20. Meso- and microscale vein structures in fore-arc basalts and boninites related to post-magmatic tectonic deformation in the outer Izu-Bonin-Mariana fore arc system: preliminary results from IODP Expedition 352

    Science.gov (United States)

    Quandt, Dennis; Micheuz, Peter; Kurz, Walter

    2016-04-01

    The International Ocean Discovery Program (IODP) Expedition 352 aimed to drill through the entire volcanic sequence of the Izu-Bonin-Mariana fore arc. Two drill sites are situated on the outer fore arc composed of fore arc basalts (FAB) whereas two more sites are located on the upper trench slope penetrating the younger boninites. First results from IODP Expedition 352 and preliminary post-cruise data suggest that FAB were generated by decompression melting during near-trench sea-floor spreading, and that fluids from the subducting slab were not involved in their genesis. Subduction zone fluids involved in boninite genesis appear to have been derived from progressively higher temperatures and pressures over time as the subducting slab thermally matured. Structures within the drill cores combined with borehole and site survey seismic data indicate that tectonic deformation in the outer Izu-Bonin-Mariana fore arc is mainly post-magmatic associated with the development of syn-tectonic sedimentary basins. Within the magmatic basement deformation was accommodated by shear along cataclastic fault zones and the formation of tension fractures, shear fractures and hybrid (tension and shear) fractures. Veins form by mineral filling of tension or hybrid fractures and show no or limited observable macroscale displacement along the fracture plane. (Low Mg-) Calcite and/or various types of zeolite are the major vein constituents, where the latter are considered to be alteration products of basaltic glass. Micrite contents vary significantly and are related to neptunian dikes. In boninites calcite develops mainly blocky shapes but veins with fibrous and stretched crystals also occur in places indicating antitaxial as well as ataxial growth, respectively. In FAB calcite forms consistently blocky crystals without any microscopic identifiable growth direction suggesting precipitation from a highly supersaturated fluid under dropping fluid pressure conditions. However, fluid pressure

  1. The value of ultrasonography in the diagnosis of portal vein thrombosis by umbilical venous catheterization

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwang Keun; Kim, Young Tong; Kim, Il Young [Chonan Hospital, Soonchunhyang University, Chonan (Korea, Republic of)

    2000-12-15

    To evaluate the usefulness of ultrasonography for diagnosis of portal vein thrombosis (PVT) associated with the umbilical venous catheterization (UVC). We reviewed the abnormal ultrasonography of 54 patients with UVC. We observed echogenic thrombus in the portal vein by ultrasonography which has a 5-10 MHz linear transducer. We evaluated the frequency of PVT, the relationship between PVT and duration of UVC, and the location of catheter tip (Group I (n=41): above the diaphragm, Group II (n=9): between the diaphragm and the liver, Group III (n=4): below the liver), the location of thrombus on US, and the change of PVT on the follow-up ultrasonography. PVT was identified in the 7 neonates (13%) among the 54 neonates with UVC. The frequency of PVT was 5% on group I, 45% on group II and 25% on group III. The 6 cases among the 7 cases(86%) of PVT were localized to the umbilical portion of the left portal vein, and there were completely resolved (n=4) or regressed (n=1) on the follow-up ultrasonography(n=5). Remaining one case of PVT was located in the right, left, and main portal veins with collateral formation, and cavernous transformation occurred on the follow-up. Most PVTs by UVC are localized to the umbilical portion of left portal vein. Ultrasonography is a useful modality to diagnose PVT by UVC.

  2. [Ultrasonic guided cannulation of the axillary vein in intensive care patients].

    Science.gov (United States)

    Schregel, W; Höer, H; Radtke, J; Cunitz, G

    1994-10-01

    Cannulation of the axillary vein is claimed to be an effective and relatively safe access to the central venous (CV) system [2, 4, 5, 8]. However, anatomical landmarks recommended for venous location (Muskulus pectoralis minor, processus coracoideus) are probably hard to identify in the majority of intensive care (ICU) patients. This investigation evaluated unidirectional 8 MHz Doppler ultrasound (US) in locating the axillary vein. Success rates and complications of this CV access in ICU patients is analysed. METHODS. The experimental design was approved by the local ethical committee (RUB). In 50 patients from our ICU cannulation of the axillary vein was attempted; all were in need of a CV line. Other CV puncture sites (except for the subclavian vein) were associated with contraindications. Patients were placed in a 15 degrees Trendelenburg position (15 exceptions); the arm was abducted to 45 degrees [5, 8]. The course of the axillary vein was located by Doppler US and marked on the skin with a felt pen. Prior to puncture, US intensity was judged by a score ranging from 0 to 4. After skin desinfection, sterile draping, and local anaesthesia, puncture of the axillary vein was attempted. The puncture kit LeaderCath 11,515 (Vygon, Aachen, FRG) was used. When venous blood could be aspirated, the Seldinger guidewire was inserted and the definite catheter placed. The experimental design allowed up to ten punctures, slightly modified in angle and direction of the needle, if puncture of the axillary vein or guide-wire placement failed. The cannulation attempt was classified as unsuccessful in the following cases: malposition, axillary vein not encountered by the puncture needle, guide-wire placement unsuccessful, or if identification and cannulation of the vein lasted more than 20 min. The puncture attempts were evaluated in respect to success rate, time, relation of US intensity to puncture attempts and CV pressure, complications, and malposition. RESULTS. Of the 50

  3. Multidetector-Row CT Findings of a Preduodenal Portal Vein Associated with Polysplenic Syndrome in an Adult: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hyun; Lee, Su Lim; Ku, Young Mi; Chun, Chang Woo [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Uijeongbu (Korea, Republic of)

    2012-03-15

    Preduodenal portal vein (PDPV) is a rare developmental anomaly in which the portal vein runs at the ventral side of the duodenum instead of at an intrapancreatic location. Understanding of this anomaly is of considerable surgical importance, because it may cause unintended portal vein injury during operations involving the gall bladder or duodenum. We recently experienced PDPV associated with polysplenia syndrome in a 49-year-old male patient who complained of persistent epigastric pain. CT portal venography with thin slab maximal intensity projection and volume rendering demonstrated the unique feature of convex anastomosis between the L-shaped mesenterico-portal vein and mesenterico-splenic vein in the mid abdomen. We report here the Multidetector-row CT findings of a rare case of PDPV.

  4. Extracorporeal shock waves as curative therapy for varicose veins?

    Directory of Open Access Journals (Sweden)

    Fiorenzo Angehrn

    2008-03-01

    Full Text Available Fiorenzo Angehrn1, Christoph Kuhn1, Ortrud Sonnabend2, Axel Voss31Klinik Piano, Biel, Switzerland; 2Pathodiagnostics, Herisau, Switzerland; 3SwiTech Medical AG, Kreuzlingen, SwitzerlandAbstract: In this prospective design study the effects of low-energy partially focused extracorporeal generated shock waves (ESW onto a subcutaneous located varicose vein – left vena saphena magna (VSM – are investigated. The treatment consisted of 4 ESW applications within 21 days. The varicose VSM of both sides were removed by surgery, and samples analyzed comparing the treated and untreated by means of histopathology. No damage to the treated varicose vein in particular and no mechanical destruction to the varicose vein’s wall could be demonstrated. However, an induction of neo-collagenogenesis was observed. The thickness of the varicose vein’s wall increased. Optimization of critical application parameters by investigating a larger number of patients may turn ESW into a non-invasive curative varicose treatment.Keywords: curative therapy, extra-cellular matrix (ECM, histopathologic changes of varicose veins, extracorporeal shock wave (ESW, progenitor cells

  5. Analysis of the hand vein pattern for people recognition

    Science.gov (United States)

    Castro-Ortega, R.; Toxqui-Quitl, C.; Cristóbal, G.; Marcos, J. Victor; Padilla-Vivanco, A.; Hurtado Pérez, R.

    2015-09-01

    The shape of the hand vascular pattern contains useful and unique features that can be used for identifying and authenticating people, with applications in access control, medicine and financial services. In this work, an optical system for the image acquisition of the hand vascular pattern is implemented. It consists of a CCD camera with sensitivity in the IR and a light source with emission in the 880 nm. The IR radiation interacts with the desoxyhemoglobin, hemoglobin and water present in the blood of the veins, making possible to see the vein pattern underneath skin. The segmentation of the Region Of Interest (ROI) is achieved using geometrical moments locating the centroid of an image. For enhancement of the vein pattern we use the technique of Histogram Equalization and Contrast Limited Adaptive Histogram Equalization (CLAHE). In order to remove unnecessary information such as body hair and skinfolds, a low pass filter is implemented. A method based on geometric moments is used to obtain the invariant descriptors of the input images. The classification task is achieved using Artificial Neural Networks (ANN) and K-Nearest Neighbors (K-nn) algorithms. Experimental results using our database show a percentage of correct classification, higher of 86.36% with ANN for 912 images of 38 people with 12 versions each one.

  6. Central Retinal Vein Occlusion Associated with Ulcerative Colitis.

    Science.gov (United States)

    Seo, Yuri; Kim, Min; Kim, Jin Hyoung; Park, Jae Jun; Lee, Sung Chul

    2016-12-01

    To report a case of central retinal vein occlusion without macular edema associated with ulcerative colitis and its novel treatment with intravitreal dexamethasone. A 40-year-old man with ulcerative colitis presented with sudden visual disturbances. An initial fundus examination showed subtle yellow-to-white patches within the inner retina of the right eye superotemporal to the fovea. There were intraretinal hemorrhages and cotton-wool spots within the superior vascular arcade and nasal to the optic disc. Despite initiation of systemic corticosteroids, 2 weeks later there was an increase in retinal hemorrhages, formation of cotton wool spots, and development of optic disc swelling in the right eye. The patient was eventually diagnosed with nonischemic central retinal vein occlusion associated with ulcerative colitis. He received sustained-release intravitreal dexamethasone, which led to the resolution of retinal hemorrhage, optic disc swelling, and cotton-wool spots. Three months after the injection, retinal hemorrhages were not detectable. However, ocular coherence imaging showed marked thinning of the inner retina at the locations that were previously hyper-reflective. Central retinal vein occlusion is an uncommon ophthalmologic manifestation associated with ulcerative colitis. Injection of intravitreal dexamethasone could be a viable treatment option in these patients even without the presence of macular edema.

  7. Gold grade distribution within an epithermal quartz vein system, Kestanelik, NW Turkey: implications for gold exploration

    Science.gov (United States)

    Gulyuz, Nilay; Shipton, Zoe; Gulyuz, Erhan; Lord, Richard; Kaymakci, Nuretdin; Kuscu, İlkay

    2017-04-01

    -hosted veins host the majority of gold mineralization (94.39%). While there is almost no correlation between the true vein thickness and the gold grade, 77.65% of high gold grades are located where the veins bend along dip. These results suggest that multiple gold precipitation mechanisms may have been active and boiling mechanism responsible for gold precipitation along the structural pathways was more effective than possible fluid-rock interaction or throttling mechanisms which will precipitate gold at adjacent alteration zones around the pathways at Kestanelik. In addition, specific structural locations such as vein bends are favorable for gold precipitation. This study emphasizes that structural architecture of the veins is one of the key controls on the location of high gold grades. In addition, adding structural data collection and mapping specific structural locations such as bends to the exploration program could permit the key locations of high gold grade to be identified faster, and to focus further drilling and assays.

  8. Radiological features of azygous vein aneurysm.

    Science.gov (United States)

    Choudhary, Arabinda Kumar; Moore, Michael

    2014-04-01

    Mediastinal masses are most commonly associated with malignancy. Azygous vein aneurysm is a very rare differential diagnosis of mediastinal mass. We report here three cases of azygous vein aneurysm including children and adult patients. In the pediatric patient it was further complicated by thrombosis and secondary pulmonary embolism. We describe the radiological features on CXR, MRI, CT, PET-CT, US and angiogram and their differential diagnosis. Imaging findings of continuity with azygous vein, layering of contrast medium on enhanced CT and dynamic MRA showing filling of the mass at the same time as the azygous vein without prior enhancement will be strongly suggestive of azygous vein aneurysm with transtracheal ultrasound being the definitive test in these patients. It is important to keep a vascular origin mass in the differential diagnosis of mediastinal masses. Also, in young healthy patients with pulmonary embolism, a vascular etiology such as azygous vein aneurysm should be carefully evaluated. This article will help the clinicians to learn about the imaging features of azygous vein aneurysm on different imaging modalities.

  9. Portal vein gas in emergency surgery

    Directory of Open Access Journals (Sweden)

    Mahmood Hind

    2008-07-01

    Full Text Available Abstract Background Portal vein gas is an ominous radiological sign, which indicates a serious gastrointestinal problem in the majority of patients. Many causes have been identified and the most important was bowel ischemia and mesenteric vascular accident. The presentation of patients is varied and the diagnosis of the underlying problem depends mainly on the radiological findings and clinical signs. The aim of this article is to show the clinical importance of portal vein gas and its management in emergency surgery. Methods A computerised search was made of the Medline for publications discussing portal vein gas through March 2008. Sixty articles were identified and selected for this review because of their relevance. These articles cover a period from 1975–2008. Results Two hundreds and seventy-five patients with gas in the portal venous system were reported. The commonest cause for portal vein gas was bowel ischemia and mesenteric vascular pathology (61.44%. This was followed by inflammation of the gastrointestinal tract (16.26%, obstruction and dilatation (9.03%, sepsis (6.6%, iatrogenic injury and trauma (3.01% and cancer (1.8%. Idiopathic portal vein gas was also reported (1.8%. Conclusion Portal vein gas is a diagnostic sign, which indicates a serious intra-abdominal pathology requiring emergency surgery in the majority of patients. Portal vein gas due to simple and benign cause can be treated conservatively. Correlation between clinical and diagnostic findings is important to set the management plan.

  10. Global search demand for varicose vein information on the internet.

    Science.gov (United States)

    El-Sheikha, Joseph

    2015-09-01

    Changes in internet search trends can provide healthcare professionals detailed information on prevalence of disease and symptoms. Chronic venous disease, more commonly known as varicose veins, is a common symptomatic disease among the adult population. This study aims to measure the change in global search demand for varicose vein information using Google over the past 8 years. The Google Trends instrument was used to measure the change in demand for the use of the local name for varicose veins in several countries across the world between January 2006 and December 2012. The measurements were normalised onto a scale relative to the largest volume of search requests received during a designated time and geographical location. Comparison of national levels of private healthcare and healthcare spending per capita to search demand was also undertaken using Organisation for Economic Co-operation and development economic measurements. Global interest has increased significantly, with linear regression demonstrating a 3.72% year-on-year increase in demand over the 8-year time period (r(2 )= 0.385, p demand significantly increased in the northern hemisphere (p demand compared to cooler winter months (demand (r(2 )= 0.120 p = 0.306). Healthcare spending per capita did not relate to search demand (r(2 )= 0.450 p = 0.077). There is increasing demand for information about varicose veins on the internet, especially during the warmer months of the year. Online search demand does not appear to be related to healthcare spending. © The Author(s) 2014.

  11. Valsalva and gravitational variability of the internal jugular vein and common femoral vein: Ultrasound assessment

    Energy Technology Data Exchange (ETDEWEB)

    Beddy, P. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland)]. E-mail: pbeddy@eircom.net; Geoghegan, T. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland); Ramesh, N. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland); Buckley, O. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland); O' Brien, J. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland); Colville, J. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland); Torreggiani, W.C. [Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24 (Ireland)

    2006-05-15

    Purpose: Central venous cannulation via the common femoral vein is an important starting point for many interventions. The purpose of this study was to determine the optimum conditions for cannulation of the femoral vein and to compare these with the relative changes in the internal jugular vein. Methods: High-resolution 2D ultrasound was utilised to determine variability of the calibre of the femoral and internal jugular veins in 10 healthy subjects. Venous diameter was assessed during the Valsalva manoeuvre and in different degrees of the Trendelenburg position. Results: The Valsalva manoeuvre significantly increased the size of the femoral and internal jugular veins. There was a relatively greater increase in femoral vein diameter when compared with the internal jugular vein of 40 and 29%, respectively. Changes in body inclination (Trendelenburg position) did not significantly alter the luminal diameter of the femoral vein. However, it significantly increased internal jugular vein diameter. Conclusions: Femoral vein cannulation is augmented by the Valsalva manoeuvre but not significantly altered by the gravitational position of the subject.

  12. Crack-seal microstructure evolution in bi-mineralic quartz-chlorite veins in shales and siltstones from the RWTH-1 well, Aachen, Germany

    Science.gov (United States)

    Becker, Stephan; Hilgers, Christoph; Kukla, Peter A.; Urai, Janos L.

    2011-04-01

    In core samples from the deep geothermal well RWTH-1 we studied Variscan quartz-chlorite veins formed by crack-seal processes in siliciclastics at the brittle to ductile transition. These sheared veins are common in sections of the well, which are interpreted as Variscan thrust zones based on image logs and seismic data. Microstructures interpreted to reflect different stages in the evolution of such crack-seal veins suggest the veins started in microcracks sealed by quartz and chlorite, to veinlets crossing multiple grains, and bundles of veinlets evolving by progressive localization into low-angle extensional shear veins and high-angle dilational jog veins. In the sheared veins, chlorite and quartz ribbons show evidence for crack-seal and simultaneous ductile shearing during vein evolution, forming peculiar fin-shaped microstructures in quartz ribbons. In high-angle dilational jogs fibrous crystals of quartz and chlorite point to multiple crack-seal events with simultaneous growth of two different mineral phases. This is interpreted to be the basic microstructural process in the veins. We extend earlier models of polycrystal growth in fractures and present a series of 2D simulations of the kinematics of crystal growth in these bi-mineralic veins for both localized and non-localized cracking. Results are compared with the observed microstructures. We show that when the relative growth rates of the two mineral phases are different, serrated grain boundaries evolve. The similarities between observation and model suggest that the assumption of our model is valid, although many second order processes require a more detailed study. We propose that the principles observed here can be applied to other bi-mineralic crack-seal veins.

  13. CORRELATION OF MICROVASCULAR STRUCTURES ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY WITH VISUAL ACUITY IN RETINAL VEIN OCCLUSION.

    Science.gov (United States)

    Kang, Joon-Won; Yoo, Romi; Jo, Youn Hye; Kim, Hyung Chan

    2017-09-01

    To analyze the correlation of superficial and deep capillary plexuses using optical coherence tomography (OCT) angiography with visual acuity in eyes with retinal vein occlusion (RVO). We retrospectively reviewed the medical records of 33 patients with retinal vein occlusion (RVO; branch retinal vein occlusion in 21 patients, central retinal vein occlusion in 12 patients) and included 33 healthy subjects as a control group, who were evaluated by OCT angiography. The OCT angiography was performed on a 3 mm × 3-mm region centered on the fovea and parafoveal area. The foveal avascular zone (FAZ), and foveal and parafoveal vascular density (VD) in superficial and deep vascular plexuses were analyzed using OCT angiography. The area of superficial and deep FAZ in eyes with RVO were larger than those in fellow eyes and control eyes (P = 0.034, P = 0.018). The superficial and deep parafoveal VDs in eyes with RVO were significantly lower than those in fellow eyes and control eyes (P = 0.001, Pretinal vein occlusion (85.7%) showed a high concordance rate with respect to the location of branch retinal vein occlusion and the lowest parafoveal VD area. The multivariate analysis showed that the deep parafoveal VD was associated with best-corrected visual acuity. The OCT angiography allows to detect FAZ enlargement, increased parafoveal capillary nonperfusion, and decreased parafoveal VD in eyes with RVO. The area of superficial FAZ and the parafoveal VD are correlated with best-corrected visual acuity in eyes with RVO.

  14. Ventriculoatrial shunting via the azygos vein.

    Science.gov (United States)

    Balasubramaniam, C; DuBois, J J; Laurent, J P; Pokorny, W J; Harberg, F J; Cheek, W R

    1990-06-01

    The treatment of hydrocephalus has evolved through many stages but the "cure" is still elusive. It is not unusual for the neurosurgeon to find that the commonly used routes for catheter placement or sites for drainage of cerebrospinal fluid (CSF) cannot be employed. The azygos vein was used to gain access to the right atrium when the CSF could not be drained into the peritoneal cavity, nor could the neck veins be used to place the catheter into the right atrium. The azygos vein is a convenient and safe route to reach the right atrium in selected patients.

  15. Portal Decompression Using the Inferior Mesenteric Vein

    Directory of Open Access Journals (Sweden)

    Paolo Gorini

    1998-01-01

    Full Text Available We report five patients with variceal hemorrhage, in three cases secondary to diffuse thrombosis of the portal, superior mesenteric and splenic veins. Mesenteric angiography demonstrated patency of the inferior mesenteric vein (IMV in each, and successful portal decompression by anastomosis of the IMV to the left renal vein (n=4 or the inferior vena cava (n=1 was accomplished. Bleeding was permanently controlled: four patients have survived from one to eight years post-operatively. Because shunt procedures utilizing the IMV are technically straightforward, subtotally decompress the portal system and avoid the right upper quadrant, they may be advantageous in certain clinical settings.

  16. [FEATURES LIVER TRANSPLANTATION IN PORTAL VEIN THROMBOSIS].

    Science.gov (United States)

    Abbasov, P A

    2015-07-01

    In 2012 - 2013 years in 265 patients for liver transplantation was performed, including in 224 (84.5%)--from a living donor, in 41 (15.5%)--from the dead body. Using a Foley catheter to stop bleeding, and the imposition of vascular sutures during endovenectomy in portal vein thrombosis (PVT) and its possible damage under all conditions. In particular, PVT IV degree (Grade IV) in order to restore blood flow in the graft using the left gastric and renal vein is an alternative, if they are cryopreserved vein may be suitably used.

  17. Varicose veins--Who should be referred?

    Science.gov (United States)

    Onida, Sarah; Davies, Alun H; Franklin, Ian

    2015-11-01

    Varicose veins are a common, progressive condition in the UK, with significant negative effects on patients' quality of life. Despite their prevalence, access to secondary care for the assessment and treatment of varicose veins can be variable throughout the country.The National Institute of Health and Care Excellence guidelines developed in 2013 provide evidence-based guidance on the referral, assessment, and management of the patient with venous disease.In this article, we review the development of the guidelines for the management of varicose veins over the last 15 years, highlighting the latest changes in referral criteria.

  18. Numerical simulation of endovenous laser treatment of the incompetent great saphenous vein with external air cooling.

    Science.gov (United States)

    Marqa, Mohamad Feras; Mordon, Serge; Hernández-Osma, Esteban; Trelles, Mario; Betrouni, Nacim

    2013-05-01

    Endovenous laser treatment (ELT) has been proposed as an alternative in the treatment of reflux of the great saphenous vein. Before the procedure, peri-saphenous subcutaneous tumescent saline solution infiltration is usually performed. However, diffusion of this tumescent fluid is rapidly observed and can potentially reduce the efficacy as a heat sink. External skin cooling with cold air was proposed as an alternative solution. The objective of this study is to compare endovenous laser treatment without and with air cooling by realistic numerical simulations. An optical-thermal damage model was formulated and implemented using finite element modeling. The general model simulated light distribution using the diffusion approximation of the transport theory, temperature rise using the bioheat equation, and laser-induced injury using the Arrhenius damage model. Parameters, used in clinical procedures, were considered: power, 15 W; pulse duration, 1 s; fiber pull back, 3-mm increments every second; cold air applied in continuous mode during ELT; and no tumescent anesthesia. Simulations were performed for vein locations at 5, 10, and 15 mm in depth, with and without air cooling. For a vein located at 15 mm in depth, no significant difference was observed with and without cooling. For a vein located at 10 mm in depth, surface temperature increase up to 45 °C is observed without cooling. For a vein located at 5 mm, without cooling, temperature increase leads to irreversible damage of dermis and epidermis. Conversely, with air cooling, surface temperature reaches a maximum of 38 °C in accordance with recordings performed on patients. ELT of the incompetent great saphenous vein with external air cooling system is a promising therapy technique. Use of cold air on the skin continuously flowing in the area of laser shot decreased significantly the heat extent and the thermal damage in the perivenous tissues and the skin.

  19. Septic thrombophlebitis of the inferior mesenteric vein and associated mesenteric abscess complicating sigmoid diverticulitis: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Seong Jae; Lee, Hae Kyung; Yi, Beom Ha; Lee, Min Hee; Hong, Hyun Sook [Dept. of Radiology, Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of)

    2013-07-15

    Thrombophlebitis occurs secondarily to inflammatory conditions of adjacent organs, and radiologic finding is essential for diagnosis. However, because of the rarity on clinical cases that involve the inferior mesenteric vein, many radiologists are unfamiliar with its location and appearance. We experience a case of septic thrombophlebitis with abscess complication sigmoid diverticulitis. CT scans reveals a low density thrombus and air in the inferior mesenteric vein, combining with perivascular fat infiltration, and focal wall defects with abscess formation. After surgical treatment, the abscess was not visible in the follow-up CT scans. Septic thrombophlebitis of the inferior mesenteric vein, although being a rare disease, should be diagnosed on CT according to the given unique location, the appearance of inflamed vein and the adjacent descending mesocolon.

  20. VeinPLUS: A Transillumination and Reflection-based Hand Vein Database

    OpenAIRE

    Gruschina, Alexander

    2015-01-01

    This paper gives a short summary of work related to the creation of a department-hosted hand vein database. After the introducing section, special properties of the hand vein acquisition are explained, followed by a comparison table, which shows key differences to existing well-known hand vein databases. At the end, the ROI extraction process is described and sample images and ROIs are presented.

  1. [Retinal vein occlusion in a young patient].

    Science.gov (United States)

    Zemba, Mihail; Ochinciuc, Uliana; Sarbu, Laura; Avram, Corina; Camburu, Raluca; Stamate, Alina

    2013-01-01

    We present a case report of a 27 years old pacient with central retinal vein occlussion and macular edema. The pacient has a significant reduction of the macular aedema with complete recovery of vision after the treatment.

  2. Vein of Galen Malformation: Outcome after Embolization

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2003-12-01

    Full Text Available The neurodevelopmental outcome after endovascular treatment of vein of Galen malformation (VOGM in 27 patients seen between 1983 and 2002 was assessed by chart review and parental questionnaires at the University of California, San Francisco.

  3. Efficacy of varicose vein surgery with preservation of the great safenous vein

    Directory of Open Access Journals (Sweden)

    Bernardo Cunha Senra Barros

    2015-04-01

    Full Text Available OBJECTIVE: To evaluate the efficacy of surgical treatment of varicose veins with preservation of the great saphenous vein. METHODS: We conducted a prospective study of 15 female patients between 25 and 55 years of age with clinical, etiologic, anatomic and pathophysiologic (CEAP classification 2, 3 and 4. The patients underwent surgical treatment of primary varicose veins with great saphenous vein (GSV preservation. Doppler ultrasonography exams were carried out in the first and third months postoperatively. The form of clinical severity of venous disease, Venous Clinical Severity Score (VCSS was completed before and after surgery. We excluded patients with history of deep vein thrombosis, smoking or postoperatively use of elastic stockings or phlebotonics. RESULTS: All patients had improved VCSS (p <0.001 and reduction in the diameter of the great saphenous vein (p <0.001. There was a relationship between VCSS and the GSV caliber, as well as with preoperative CEAP. There was improvement in CEAP class in nine patients when compared with the preoperative period (p <0.001. CONCLUSION: The varicose vein surgery with preservation of the great saphenous vein had beneficial effects to the GSV itself, with decreasing caliber, and to the symptoms when the vein had maximum caliber of 7.5 mm, correlating directly with the CEAP. The decrease in GSV caliber, even without complete abolition of reflux, leads to clinical improvement by decreasing the reflux volume.

  4. Isolated inferior mesenteric portal hypertension with giant inferior mesenteric vein and anomalous inferior mesenteric vein insertion

    Directory of Open Access Journals (Sweden)

    G Raghavendra Prasad

    2013-01-01

    Full Text Available Extrahepatic portal hypertension is not an uncommon disease in childhood, but isolated inferior mesenteric portal varices and lower gastrointestinal (GI bleed have not been reported till date. A 4-year-old girl presented with lower GI bleed. Surgical exploration revealed extrahepatic portal vein obstruction with giant inferior mesenteric vein and colonic varices. Inferior mesenteric vein was joining the superior mesenteric vein. The child was treated successfully with inferior mesenteric - inferior vena caval anastomosis. The child was relieved of GI bleed during the follow-up.

  5. CT in thrombosed dilated posterior epidural vein

    Energy Technology Data Exchange (ETDEWEB)

    Bammatter, S.; Schnyder, P.; Preux, J. de

    1987-05-01

    The authors report a case of thrombosis of the distal end of an enlarged right posterior epidural vein. The patient had a markedly narrow lumbar canal due to L5 spondylolisthesis. The dilated vein and the thrombosis were displayed by computed tomography but remained unrecognized until surgery. Pathogenesis of this condition is discussed. A review of the English, French and German literature revealed no prior radiological reports of a similar condition.

  6. Primary leiomyosarcoma of the innominate vein.

    Science.gov (United States)

    Illuminati, Giulio; Miraldi, Fabio; Mazzesi, Giuseppe; D'urso, Antonio; Ceccanei, Gianluca; Bezzi, Marcello

    2007-01-01

    Primary venous leiomyosarcoma is rare. We report the case of a primary leiomyosarcoma of the left innominate vein, with neoplastic thrombus extending into the left jugular and subclavian veins. The tumor was curatively resected en bloc with anterior mediastinal and laterocervical lymphatics, through a median sternotomy prolonged into left cervicotomy. Primary venous sarcomas may be associated with prolonged survival in individual cases, with curative resection recommended as the standard treatment, in the absence of distant spread.

  7. The umbilical and paraumbilical veins of man.

    OpenAIRE

    Martin, B F; Tudor, R G

    1980-01-01

    During its transit through the umbilicus structural changes occur in the thick wall of the extra-abdominal segment of the umbilical vein whereby the components of the intra-abdominal segment acquire an essentially longitudinal direction and become arranged in fibro-elastic and fibro-muscular zones. The vein lumen becomes largely obliterated by asymmetrical proliferation of loose subendothelial conective tissue. The latter forms a new inner zone within which a small segment of the lumen persis...

  8. Branch Retinal Vein Occlusion and Its Management

    Institute of Scientific and Technical Information of China (English)

    Desmond; Archer

    1992-01-01

    The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the...

  9. Endovascular treatment of iliac vein compression syndrome

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-you; LI Xiao-qiang; QIAN Ai-min; SANG Hong-fei; RONG Jian-jie; ZHU Li-wei

    2011-01-01

    Background Iliac vein compression syndrome (IVCS),the symptomatic compression of the left common iliac vein between the right common iliac artery and the vertebrae,is not an uncommon condition.The aim of this research was to retrospectively evaluate long-term outcome and the significance of endovascular treatment in patients with left IVCS.Methods Between January 1997 and September 2008,296 patients received interventional therapy in the left common iliac vein.In the second stage,170 cases underwent saphenous vein high ligation and stripping.Two hundred and thirty-one cases were followed up over a period of 6 to 120 months (average 46 months) and evaluated for symptom improvement with color ultrasound and ascending venography.Results The stenotic or occlusive segments of the left iliac vein were successfully dilated in 285 cases,of whom 272 received stent implantation therapy.Most of the patients achieved satisfactory results on discharge.During the follow-up period,varicose veins were alleviated in 98.7% of the patients,and leg swelling disappeared or was obviously relieved in 84% of cases.About 85% of leg ulcers completely healed.The total patency rate was 91.7% as evaluated with color ultrasound and 91.5% with ascending venography.Conclusions Endovascular treatment of IVCS provides effective symptomatic improvement and good long-term patency in most patients.

  10. Portal vein thrombosis in children and adolescents.

    Science.gov (United States)

    Schettino, Graziela C M; Fagundes, Eleonora D T; Roquete, Mariza L V; Ferreira, Alexandre R; Penna, Francisco J

    2006-01-01

    To review the literature on portal vein thrombosis in children and adolescents, focusing on its diagnosis, complications and treatment. The medical literature of the past 10 years was reviewed using the PubMed and MEDLINE search engines, with major focus on portal vein thrombosis and its clinical outcomes. The following keywords or expressions were used for the web search: portal vein thrombosis, extra-hepatic portal vein obstruction, prognosis, children, portal hypertension, esophagogastric varices. Additionally, we also reviewed the articles cited in the references of the initially selected papers, as well as relevant textbooks. Portal vein thrombosis is one of the most common causes of portal hypertension among children. The initial clinical manifestation is characterized either by episodes of upper gastrointestinal bleeding or by splenomegaly on routine clinical examination. The major complications include upper gastrointestinal bleeding, hypersplenism secondary to splenomegaly, growth retardation, and portal biliopathy. The diagnosis is made by abdominal Doppler ultrasonography. Treatment is targeted at the complications and includes primary and secondary prophylaxis against upper gastrointestinal bleeding (which results from the rupture of esophageal varices), and portosystemic shunting in selected cases. Portal vein thrombosis is one of the major triggers of upper gastrointestinal bleeding in children. Bleeding episodes have a remarkable effect on the quality of life of affected patients. Thus, appropriate diagnosis and treatment are needed in order to reduce morbidity and mortality.

  11. Veins improve fracture toughness of insect wings.

    Directory of Open Access Journals (Sweden)

    Jan-Henning Dirks

    Full Text Available During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m. However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm. This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species.

  12. Additive manufacturing of micrometric crystallization vessels and single crystals

    Science.gov (United States)

    Halevi, Oded; Jiang, Hui; Kloc, Christian; Magdassi, Shlomo

    2016-11-01

    We present an all-additive manufacturing method that is performed at mild conditions, for the formation of organic single crystals at specific locations, without any photolithography prefabrication process. The method is composed of two steps; inkjet printing of a confinement frame, composed of a water soluble electrolyte. Then, an organic semiconductor solution is printed within the confinement to form a nucleus at a specific location, followed by additional printing, which led to the growth of a single crystal. The specific geometry of the confinement enables control of the specific locations of the single crystals, while separating the nucleation and crystal growth processes. By this method, we printed single crystals of perylene, which are suitable for the formation of OFETs. Moreover, since this method is based on a simple and controllable wet deposition process, it enables formation of arrays of single crystals at specific locations, which is a prerequisite for mass production of active organic elements on flexible substrates.

  13. Scattering removal for finger-vein image restoration.

    Science.gov (United States)

    Yang, Jinfeng; Zhang, Ben; Shi, Yihua

    2012-01-01

    Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of finger-vein image degradation, a biological optical model (BOM) specific to finger-vein imaging is proposed according to the principle of light propagation in biological tissues. Based on BOM, the light scattering component is sensibly estimated and properly removed for finger-vein image restoration. Finally, experimental results demonstrate that the proposed method is powerful in enhancing the finger-vein image contrast and in improving the finger-vein image matching accuracy.

  14. Variations in the anatomical relationship between the common carotid artery and the internal jugular vein

    Science.gov (United States)

    García, Alberto; Bustamante, Luis; Castillo, José Luis; Sebastián Martínez, Juan

    2015-01-01

    Introduction: The internal jugular vein locates anterior or anterolateral to the common carotid artery in two-thirds of the subjects studied by ultrasound when the head is in a rotated position. Aim: To identify variables associated with the anterior location of the internal jugular vein. Methods: Ultrasound examinations were performed with the patients in the supine position, with the head rotated to the opposite side. The proximal third of the neck was visualized transversely with a 7.5-mHz transducer. The relationship between the vessels was described in accordance with the proportion of the artery overlapped by the vein. Univariate comparisons and a multivariate analysis of potential variables that may affect the anatomic relationships were performed. Results: Seventy-eight patients were included, 44 of whom were men. The patients' ages ranged from 17 to 90 years (median 64.0, interquartile range 41-73). The right and left sides were studied 75 and 73 times, respectively. The vein was located lateral to the artery in 24.3% (95%CI= 17.4-32.2) of the studies, anterolateral in 33.8% (95%CI= 26.2-41.4) and anterior in 41.9% (95%CI= 33.9-49.8). The multivariate analysis identified age group (OR= 3.7, 95% CI 2.1-6.4) and, less significantly, the left side (OR= 1.7, 95%CI= 0.8-3.5) and male gender (OR= 1.2, 95%CI= 0.6-2.7) as variables associated with the anterior position of the vein. Conclusión: The anterior position of the internal jugular vein relative to the common carotid artery increases gradually with age. Additionally, left-sided localization and male sex further increased the probability of an anterior position. PMID:26309339

  15. Scattering Removal for Finger-Vein Image Restoration

    OpenAIRE

    Jinfeng Yang; Ben Zhang; Yihua Shi

    2012-01-01

    Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of f...

  16. An effective preprocessing method for finger vein recognition

    Science.gov (United States)

    Peng, JiaLiang; Li, Qiong; Wang, Ning; Abd El-Latif, Ahmed A.; Niu, Xiamu

    2013-07-01

    The image preprocessing plays an important role in finger vein recognition system. However, previous preprocessing schemes remind weakness to be resolved for the high finger vein recongtion performance. In this paper, we propose a new finger vein preprocessing that includes finger region localization, alignment, finger vein ROI segmentation and enhancement. The experimental results show that the proposed scheme is capable of enhancing the quality of finger vein image effectively and reliably.

  17. Gonadal vein tumor thrombosis due to renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Hamidreza Haghighatkhah

    2015-01-01

    Full Text Available Renal cell carcinoma (RCC had a tendency to extend into the renal vein and inferior vena cava, while extension into the gonadal vein has been rarely reported. Gonadal vein tumor thrombosis appears as an enhancing filling defect within the dilated gonadal vein anterior to the psoas muscle and shows an enhancement pattern identical to that of the original tumor. The possibility of gonadal vein thrombosis should be kept in mind when looking at an imaging study of patients with RCC

  18. Augmented reality based real-time subcutaneous vein imaging system

    OpenAIRE

    Ai, Danni; Yang, Jian; Fan, Jingfan; Zhao, Yitian; Song, Xianzheng; Shen, Jianbing; Shao, Ling; Wang, Yongtian

    2016-01-01

    A novel 3D reconstruction and fast imaging system for subcutaneous veins by augmented reality is presented. The study was performed to reduce the failure rate and time required in intravenous injection by providing augmented vein structures that back-project superimposed veins on the skin surface of the hand. Images of the subcutaneous vein are captured by two industrial cameras with extra reflective near-infrared lights. The veins are then segmented by a multiple-feature clustering method. V...

  19. Leaf vein segmentation using Odd Gabor filters and morphological operations

    OpenAIRE

    Katyal, Vini; Aviral

    2012-01-01

    Leaf vein forms the basis of leaf characterization and classification. Different species have different leaf vein patterns. It is seen that leaf vein segmentation will help in maintaining a record of all the leaves according to their specific pattern of veins thus provide an effective way to retrieve and store information regarding various plant species in database as well as provide an effective means to characterize plants on the basis of leaf vein structure which is unique for every specie...

  20. Nutcracker Syndrome Complicated by Left Renal Vein Thrombosis

    Directory of Open Access Journals (Sweden)

    Faouzi Mallat

    2013-01-01

    Full Text Available Isolated renal vein thrombosis is a rare entity. We present a patient whose complaint of flank pain led to the diagnosis of a renal vein thrombosis. In this case, abdominal computed tomography angiography was helpful in diagnosing the nutcracker syndrome complicated by the renal vein thrombosis. Anticoagulation was started and three weeks later, CTA showed complete disappearance of the renal vein thrombosis. To treat the Nutcracker syndrome, we proposed left renal vein transposition that the patient consented to.

  1. Nutcracker syndrome complicated by left renal vein thrombosis.

    Science.gov (United States)

    Mallat, Faouzi; Hmida, Wissem; Jaidane, Mehdi; Mama, Nadia; Mosbah, Faouzi

    2013-01-01

    Isolated renal vein thrombosis is a rare entity. We present a patient whose complaint of flank pain led to the diagnosis of a renal vein thrombosis. In this case, abdominal computed tomography angiography was helpful in diagnosing the nutcracker syndrome complicated by the renal vein thrombosis. Anticoagulation was started and three weeks later, CTA showed complete disappearance of the renal vein thrombosis. To treat the Nutcracker syndrome, we proposed left renal vein transposition that the patient consented to.

  2. Gonadal vein tumor thrombosis due to renal cell carcinoma.

    Science.gov (United States)

    Haghighatkhah, Hamidreza; Karimi, Mohammad Ali; Taheri, Morteza Sanei

    2015-01-01

    Renal cell carcinoma (RCC) had a tendency to extend into the renal vein and inferior vena cava, while extension into the gonadal vein has been rarely reported. Gonadal vein tumor thrombosis appears as an enhancing filling defect within the dilated gonadal vein anterior to the psoas muscle and shows an enhancement pattern identical to that of the original tumor. The possibility of gonadal vein thrombosis should be kept in mind when looking at an imaging study of patients with RCC.

  3. Corrosion cast study of the canine hepatic veins.

    Science.gov (United States)

    Uršič, M; Vrecl, M; Fazarinc, G

    2014-11-01

    This study presents a detailed description of the distribution, diameters and drainage patterns of hepatic veins on the basis of the corrosion cast analysis in 18 dogs. We classified the hepatic veins in three main groups: the right hepatic veins of the caudate process and right lateral liver lobe, the middle hepatic veins of the right medial and quadrate lobes and the left hepatic veins of both left liver lobes and the papillary process. The corrosion cast study showed that the number of the veins in the Nomina Anatomica Veterinaria and most anatomical textbooks is underestimated. The number of various-sized hepatic veins of the right liver division ranged from 3 to 5 and included 1 to 4 veins from the caudate process and 2 to 4 veins from the right lateral liver lobe. Generally, in all corrosion casts, one middle-sized vein from the right part of the right medial lobe, which emptied separately in the caudal vena cava, was established. The other vein was a large-sized vein from the remainder of the central division, which frequently joined the common left hepatic vein from the left liver lobes. The common left hepatic vein was the largest of all the aforementioned hepatic veins.

  4. [Saccular aneurysm of the azygos vein in a patient with azygos accessory fissure].

    Science.gov (United States)

    Córdoba Rovira, S M; Guedea Martin, A; Salvador Adell, I; Elias Artiga, J

    2015-01-01

    The saccular aneurysm of the azygos vein is an extremely rare condition, which when located in the path of an accesory pulmonary fissure, becomes a diagnostic challenge because it can be mistaken for tumors arising from the accesory pleura, like solitary fibrous tumor of the pleura or mesothelioma. The diagnosis should ideally be done by non-invasive methods such as CT or MR angiographic technique in multiple phases, thus avoiding unnecessary surgical intervention. This case is exceptional because, to our knowledge, it is the first to report both concomitant clinical situations, an aneurysm of the azygos vein in the pathway of its accessory fissure.

  5. Physiological interpretations of radiographic findings on malformations of small veins: seriality of cisterns, communications to systemic veins and relationship to muscles

    Science.gov (United States)

    Morita, Nobuo; Terada, Tomoaki; Sato, Morio; Sonomura, Tetsuo

    2014-01-01

    Objectives To re-evaluate the fluoroscopic findings of venous malformation by cine mode cisternography. Methods Using direct injection cine-cisternography, we studied 49 venous malformation lesions in the head and neck of 30 patients who were scheduled to undergo ethanol sclerotherapy. The diameter of definitively measurable 46 lesions was 21.7 ± 10.5 mm (mean ± SD, range: 6.0–48.0 mm). The injection was continued until the draining veins were clearly observed. Outflow communications between cisterns and systemic veins were classified into Type 1, no visible drainage; Type 2, draining into a normal venous system; and Type 3, with abnormally ectatic draining veins. The topological relationships of the lesions to surrounding structures were addressed using computed tomography, magnetic resonance imaging or ultrasonogram. Treatment results were evaluated. Results The direct injection cine-cisternography showed the typical ‘bunch of grapes’ pattern, and revealed serial cisternal, followed by the appearance of outflow/draining veins in all lesions. There were no Type 1, 47 Type 2 and two Type 2 outflow pattern. Satellite lesions emerged via the communicating veins in six lesions. Of the all 49 lesions, 48 were located in or on the muscle fascia. Sclerotherapy was safely completed in all Type 2 lesions with satisfactory results, but for the Type 3 lesions treatment was limited to be partial to avoid complications. Conclusions The present study suggested that communications from venous malformation to the systemic vein are fluoroscopically confirmable. These radiographic findings were thought explainable in relation to developmental nature or facilitating process of venous malformation. PMID:23223003

  6. Veining Failure and Hydraulic Fracturing in Shales

    Science.gov (United States)

    Mighani, S.; Sondergeld, C. H.; Rai, C. S.

    2014-12-01

    During the hydraulic fracturing, the pressurized fluid creates new fractures and reactivates existing natural fractures forming a highly conductive Stimulated Reservoir Volume (SRV) around the borehole. We extend the previous work on Lyons sandstone and pyrophyllite to anisotropic shale from the Wolfcamp formation. We divide the rock anisotropy into two groups: a) conventional and b) unconventional (shaly) anisotropy. X-ray Computed Tomography (CT), compressional velocity anisotropy, and SEM analysis are used to identify three causes of anisotropy: bedding planes, clay lamination, and calcite veins. Calcite vein is a subsequently filled with calcite bonded weakly to the matrix. Velocity anisotropy and visual observations demonstrate the calcite filled veins to be mostly subparallel to the fabric direction. Brazilian tests are carried out to observe the fracture initiation and propagation under tension. High speed photography (frame rate 300,000 frame/sec) was used to capture the failure. Strain gauges and Acoustic Emission (AE) sensors recorded the deformation leading up to and during failure. SEM imaging and surface profilometry were employed to study the post-failure fracture system and failed surface topology. Fracture permeability was measured as a function of effective stress. Brazilian tests on small disks containing a centered single vein revealed the shear strength of the veins. We interpret the strain data and number, frequency, and amplitude of AE events which are correlated well with the observed fracture process zone, surface roughness, and permeability. The unpropped fracture has enhanced permeability by two orders of magnitude. The observed anisotropic tensile failure seems to have a universal trend with a minimum strength occurring at 15o orientation with respect to the loading axis. The veins at 15o orientation with respect to the loading axis were easily activated at 30% of the original failure load. The measured strength of the vein is as low as 6

  7. A new approach for sclera vein recognition

    Science.gov (United States)

    Thomas, N. L.; Du, Yingzi; Zhou, Zhi

    2010-04-01

    The vein structure in the sclera is stable over time, unique to each person, and well suited for human identification. A few researchers have performed sclera vein pattern recognition and reported promising initial results. Sclera recognition poses several challenges: the vein structure moves and deforms with the movement of the eye; images of sclera patterns are often defocused and/or saturated; and, most importantly, the vein structure in the sclera is multi-layered and has complex non-linear deformation. In this paper, we proposed a new method for sclera recognition: First, we developed a color-based sclera region estimation scheme for sclera segmentation. Second, we designed a Gabor wavelet-based sclera pattern enhancement method, and an adaptive thresholding method to emphasize and binarize the sclera vein patterns. Third, we proposed a line descriptor-based feature extraction, registration, and matching method that is illumination-, scale-, orientation-, and deformation-invariant, and can mitigate the multi-layered deformation effects exhibited in the sclera and tolerate segmentation error. It is empirically verified using the UBIRIS database that the proposed method can perform accurate sclera recognition.

  8. Optimization of subcutaneous vein contrast enhancement

    Science.gov (United States)

    Zeman, Herbert D.; Lovhoiden, Gunnar; Deshmukh, Harshal

    2000-05-01

    A technique for enhancing the contrast of subcutaneous veins has been demonstrated. This techniques uses a near IR light source and one or more IR sensitive CCD TV cameras to produce a contrast enhanced image of the subcutaneous veins. This video image of the veins is projected back onto the patient's skin using a n LCD video projector. The use of an IR transmitting filter in front of the video cameras prevents any positive feedback from the visible light from the video projector from causing instabilities in the projected image. The demonstration contrast enhancing illuminator has been tested on adults and children, both Caucasian and African-American, and it enhances veins quite well in all cases. The most difficult cases are those where significant deposits of subcutaneous fat are present which make the veins invisible under normal room illumination. Recent attempts to see through fat using different IR wavelength bands and both linearly and circularly polarized light were unsuccessful. The key to seeing through fat turns out to be a very diffuse source of RI light. Results on adult and pediatric subjects are shown with this new IR light source.

  9. Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy – Case report

    Science.gov (United States)

    Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B.

    2014-01-01

    62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. Conclusion The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival. PMID:25568802

  10. Analysis of Rare Earth Elements (REE) in vein quartz and quartz-sandstone host rock in the Zhelannoe high purity quartz deposit, Russia

    Science.gov (United States)

    Zemskova, Marina; Prokofiev, Vsevolod; Bychkov, Andrey

    2015-04-01

    The Zhelannoe high purity quartz deposit is located on the western slope of the Polar Urals. It is one of the largest deposits of vein quartz and rock crystal in Russia. Most of the mineralization is hosted within a single horizon of very firm quartz-sandstone, where plastic deformation did not occur almost entirely. All tectonic stress was released by the development of numerous thrust faults of different scales. Cavities formed during this process were later filled with quartz and rock crystal. In order to obtain more details on conditions under which mineralization took place, analysis of trace element contents in vein quartz and host rocks, and the micro-thermometric study of fluid inclusions in quartz have been carried out. The trace element composition of vein quartz and of the host rock has been determined by ICP-MS. The results have shown that concentrations of most of the 46 studied elements in quartz are two orders of magnitude lower than in chondrite, and more than three orders of magnitude lower than in the upper crust. Even though Pb and Li have the highest concentrations in quartz samples, levels are only nearly comparable in chondrite, and substantially lower in the upper crust. At the same time, negative anomalies of Pb and Li concentrations in the host rock may indicate the removal of these elements during vein quartz formation. Contents of most REEs are two orders of magnitude lower than in chondrite, and three orders of magnitude lower than in the host rock. Generally, the patterns of REE distribution in vein quartz and the host rock express a clear correlation; confirming the genetic link between vein quartz and quartz-sandstone host rock. However, the process of quartz recrystallization led to an intense decrease of REEs content, and of all other impurities, which consequently influenced industrial value of the Zhelannoe deposit. As a result of the micro-thermometric study of fluid inclusions in quartz, the following physical

  11. [The "crystals" in the sugar beet (Beta vulgaris L.) leaves].

    Science.gov (United States)

    Semenova, G A; Romanova, A K

    2011-01-01

    Crystal containing cells widely distributed in plant tissues, though the origin of the crystals and their functions are still opened to question. Membrane vesicles in beet leaves are visible in electronic microscope. They originate in cytoplasm and penetrate into vacuole by pinocytosis with participation of tonoplast. In light microscope, vesicles are luminous likewise crystals in crystal cells. Such vesicles-"crystals" fulfill crystal cells also. The content of vesicles-"crystals" are electronic transparent at every path of leaf development. It was proposed that distinct vesicles-"crystals" in cytoplasm and vacuole and mass of them in crystal cells, vein bundles, and epidermal cells--all of them are lytic compartments. Later, obviously, true crystals are formed.

  12. Crystals in crystals

    DEFF Research Database (Denmark)

    Christensen, Claus H.; Schmidt, I.; Carlsson, A.;

    2005-01-01

    A major factor governing the performance of catalytically active particles supported on a zeolite carrier is the degree of dispersion. It is shown that the introduction of noncrystallographic mesopores into zeolite single crystals (silicalite-1, ZSM-5) may increase the degree of particle dispersion...... of the zeolite particles, particularly after thermal treatment. When using mesoporous zeolites, the particles were evenly distributed throughout the mesopore system of the zeolitic support, even after calcination, leading to nanocrystals within mesoporous zeolite single crystals....

  13. The placement of an implantable chemoport via the external jugular vein as a primary route

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Moon Sang; Shin, Byung Seok [Chungnam National University Hospital, Daejeon (Korea, Republic of); Park, Mi Hyun [Taejon Veterans Hospital, Daejeon (Korea, Republic of)

    2008-03-15

    To evaluate the usefulness and safety of the placement of an implantable chemoport via external jugular vein as a primary route for chemotherapy. Between January 2006 and June 2007, a total of 108 implantable chemoports were placed on 325 patients for chemotherapy via the external jugular vein as a primary route. We placed a 9.6 F single lumen chemoport using a surgical procedure (n = 89) and an interventional procedure (n = 19), and evaluated the duration of catheterization days and treatment complications. An implantable chemoport was successfully installed in all cases. Furthermore, the duration of catheterization ranged from 2 to 461 days (mean: 187 days, total catheter days: 21,994). In addition, a total of 85 chemoports were removed due to complications (n = 7) and termination of chemotherapy (n 78). A transient pulmonary air embolism occurring during a procedure was observed in one case. No pneumothorax or catheter malpositions were observed in the study subjects. Two chemoports were removed two days after implantation due to persistent tachycardia. In addition, five late complications occurred, which resulted in catheter occlusion (3 cases) (3%, 0.14/1000 catheter day) and infection in (2 cases) (2%, 0.09/1000 Catheter days). Lastly, no symptoms were attributed to a central vein thrombosis. The results of this study suggest that the implantation of chemoports via the external jugular vein is a safe procedure. Moreover, the selection of the external jugular vein as a primary route is useful in determining chemoport insertion locations.

  14. Image Registration of Cone-Beam Computer Tomography and Preprocedural Computer Tomography Aids in Localization of Adrenal Veins and Decreasing Radiation Dose in Adrenal Vein Sampling

    Energy Technology Data Exchange (ETDEWEB)

    Busser, Wendy M. H., E-mail: wendy.busser@radboudumc.nl; Arntz, Mark J.; Jenniskens, Sjoerd F. M. [Radboud University Medical Center, Department of Radiology, Section of Interventional Radiology (Netherlands); Deinum, Jaap [Radboud University Medical Center, Department of General Internal Medicine (Netherlands); Hoogeveen, Yvonne L.; Lange, Frank de; Schultze Kool, Leo J. [Radboud University Medical Center, Department of Radiology, Section of Interventional Radiology (Netherlands)

    2015-08-15

    PurposeWe assessed whether image registration of cone-beam computed tomography (CT) (CBCT) and contrast-enhanced CT (CE-CT) images indicating the locations of the adrenal veins can aid in increasing the success rate of first-attempts adrenal vein sampling (AVS) and therefore decreasing patient radiation dose.Materials and Methods CBCT scans were acquired in the interventional suite (Philips Allura Xper FD20) and rigidly registered to the vertebra in previously acquired CE-CT. Adrenal vein locations were marked on the CT image and superimposed with live fluoroscopy and digital-subtraction angiography (DSA) to guide the AVS. Seventeen first attempts at AVS were performed with image registration and retrospectively compared with 15 first attempts without image registration performed earlier by the same 2 interventional radiologists. First-attempt AVS was considered successful when both adrenal vein samples showed representative cortisol levels. Sampling time, dose-area product (DAP), number of DSA runs, fluoroscopy time, and skin dose were recorded.ResultsWithout image registration, the first attempt at sampling was successful in 8 of 15 procedures indicating a success rate of 53.3 %. This increased to 76.5 % (13 of 17) by adding CBCT and CE-CT image registration to AVS procedures (p = 0.266). DAP values (p = 0.001) and DSA runs (p = 0.026) decreased significantly by adding image registration guidance. Sampling and fluoroscopy times and skin dose showed no significant changes.ConclusionGuidance based on registration of CBCT and previously acquired diagnostic CE-CT can aid in enhancing localization of the adrenal veins thereby increasing the success rate of first-attempt AVS with a significant decrease in the number of used DSA runs and, consequently, radiation dose required.

  15. MRI manifestations of enlarged superior ophthalmic vein

    Institute of Scientific and Technical Information of China (English)

    WEI Rui-li; MA Xiao-ye; CAI Ji-ping; ZHU Huang

    2002-01-01

    Objective:To assess MRI in the evaluation of enlarged superior ophthalmic vein (SOV). Methods: MRI manifestations and etiology of forty-six patients with enlarged SOV were analyzed. Results: SOV enlargement was noted to occur in carotid-cavernous fistula, ophthalmic Graves'disease, Tolosa-Hunt syndrome, inflammation at the apex of the orbit, orbital pseudotumor and thrombosis of cavernous sinus. The dilated vein appeared as signal void tubular shadows on both T1 and T2 weighted images. The diameter of the enlarged vein was 3.5-6.0 mm. Extraocular muscle enlargement, orbital pathologies, enlarged carotid cavernous sinus etc were also revealed by MRI. Conclusion: The dilated SOV may be well demonstrated by MRI. The etiological diagnosis of enlarged SOV can be made in combination with the associated findings.

  16. Pathogenesis of varicose veins - lessons from biomechanics.

    Science.gov (United States)

    Pfisterer, Larissa; König, Gerd; Hecker, Markus; Korff, Thomas

    2014-03-01

    The development of varicose veins or chronic venous insufficiency is preceded by and associated with the pathophysiological remodelling of the venous wall. Recent work suggests that an increase in venous filling pressure is sufficient to promote varicose remodelling of veins by augmenting wall stress and activating venous endothelial and smooth muscle cells. In line with this, known risk factors such as prolonged standing or an obesity-induced increase in venous filling pressure may contribute to varicosis. This review focuses on biomechanically mediated mechanisms such as an increase in wall stress caused by venous hypertension or alterations in blood flow, which may be involved in the onset of varicose vein development. Finally, possible therapeutic options to counteract or delay the progress of this venous disease are discussed.

  17. Left ventricular pacing lead positioning in the target vein of the coronary sinus: description of a challenging case.

    Science.gov (United States)

    Frattini, Folco; Rordorf, Roberto; Angoli, Luigi; Pentimalli, Francesco; Vicentini, Alessandro; Petracci, Barbara; Magrini, Giulia; Landolina, Maurizio

    2008-04-01

    The optimal left ventricular pacing location for cardiac resynchronization therapy should be individualized according to the site of maximal mechanical delay. However, the presence of vein stenosis or kinking in coronary sinus (CS) anatomy could hamper lead implantation in the target vessel. We describe the case of a patient with dilated cardiomyopathy and a dual-chamber pacemaker referred for upgrading to a biventricular device owing to New York Heart Association III heart failure symptoms. Tissue Doppler analysis before implantation showed that the area of maximum activation delay was located in the posterolateral region of the left ventricle. Insertion of the lead into a posterolateral vein of the CS by means of the standard over-the-wire approach was unsuccessful due to the presence of a stenosis at the ostium of the vein. Lead placement in an anterior vein of the CS was unsatisfactory owing to a poor local delay from QRS onset. After balloon vein angioplasty, the pacing lead passed through the stenotic tract at the ostium of the target vein and was successfully positioned in the posterolateral region. Three months after pacemaker implantation, echocardiography showed an important reduction in the indexes of both inter- and intraventricular asynchrony and a significant left ventricular reverse remodeling.

  18. Vein versus tragal perichondrium in stapedotomy.

    Science.gov (United States)

    Schmerber, Sébastien; Cuisnier, Olivier; Charachon, Robert; Lavieille, Jean-Pierre

    2004-09-01

    To assess, in otosclerosis surgery, whether the vein or the tragal perichondrium in stapedotomy with interposition yields the better long-term hearing outcome. A retrospective chart review of prospectively collected audiometric data of 452 ears. Academic tertiary otology-neurotology referral center. Four hundred fifty-two stapedotomies with interposition were performed in 412 patients (bilateral in 40 patients) by the senior author (R.C.) between 1987 and 1998. A tragal perichondrium graft was used in 314 cases and a vein graft was used in 138 cases as sealing material of the oval window. Audiometric data were recorded at 4 months, at 1 year, and at 3 years after surgery after American Academy of Otolaryngology-Head and Neck Surgery guidelines, except for thresholds at 3 kHz, which were not available and which were replaced with those at 4 kHz. There were no significant intergroup differences in initial or late postoperative hearing outcome with regard to change in the pure-tone average bone conduction and air-bone gaps, or sensorineural hearing loss. Ears treated with a vein graft showed statistically better postoperative 2-kHz air-bone gap closure (p =0.0157), but the pure-tone average air-bone gap difference was not significant. Postoperative air-bone gap closure to within 10 dB was achieved in 91% of cases in the vein group and in 76% of cases in the perichondrium group. Specific study of the bone conduction level at 4 kHz showed a sensorineural hearing loss greater than 10 dB in 8% of cases in the vein group and in 11% of cases in the perichondrium group. One case of complete sensorineural hearing loss was observed with a tragal perichondrium graft (0.22%). These results suggest that the vein should be preferred to the tragal perichondrium in stapedotomy with interposition.

  19. Duplicated Ižnternal Juguler Vein

    Directory of Open Access Journals (Sweden)

    Ahmet Kirbas

    2014-03-01

    Full Text Available    Duplicated internal juguler vein (DIJV is a rare anomaly and reported incidence is 0.4 % in the literature. A 45-year-old female patient was referred to our hospital because of non pulsatile neck swelling. The magnetic resonance image (MRI showed left IJVs divided at the angles of the mandible running anterior to the common carotid artery until anterior mediastinal level. Clinicians should be aware of the rare possibility of duplicated IJVs in patients presenting with neck swelling. The development of imaging technics have revealed more cases of duplicated internal juguler vein.

  20. Deep vein thrombosis: a clinical review

    Directory of Open Access Journals (Sweden)

    Kesieme EB

    2011-04-01

    Full Text Available Emeka Kesieme1, Chinenye Kesieme2, Nze Jebbin3, Eshiobo Irekpita1, Andrew Dongo11Department of Surgery, Irrua Specialist Teaching Hospital, Irrua, Nigeria; 2Department of Paediatrics, Irrua Specialist Teaching Hospital, Irrua, Nigeria; 3Department of Surgery, University of Port Harcourt Teaching Hospital, Port-Harcourt, NigeriaBackground: Deep vein thrombosis (DVT is the formation of blood clots (thrombi in the deep veins. It commonly affects the deep leg veins (such as the calf veins, femoral vein, or popliteal vein or the deep veins of the pelvis. It is a potentially dangerous condition that can lead to preventable morbidity and mortality.Aim: To present an update on the causes and management of DVT.Methods: A review of publications obtained from Medline search, medical libraries, and Google.Results: DVT affects 0.1% of persons per year. It is predominantly a disease of the elderly and has a slight male preponderance. The approach to making a diagnosis currently involves an algorithm combining pretest probability, D-dimer testing, and compression ultrasonography. This will guide further investigations if necessary. Prophylaxis is both mechanical and pharmacological. The goals of treatment are to prevent extension of thrombi, pulmonary embolism, recurrence of thrombi, and the development of complications such as pulmonary hypertension and post-thrombotic syndrome.Conclusion: DVT is a potentially dangerous condition with a myriad of risk factors. Prophylaxis is very important and can be mechanical and pharmacological. The mainstay of treatment is anticoagulant therapy. Low-molecular-weight heparin, unfractionated heparin, and vitamin K antagonists have been the treatment of choice. Currently anticoagulants specifically targeting components of the common pathway have been recommended for prophylaxis. These include fondaparinux, a selective indirect factor Xa inhibitor and the new oral selective direct thrombin inhibitors (dabigatran and selective

  1. Renal actinomycosis with concomitant renal vein thrombosis.

    Science.gov (United States)

    Chang, Dong-Suk; Jang, Won Ik; Jung, Ji Yoon; Chung, Sarah; Choi, Dae Eun; Na, Ki-Ryang; Lee, Kang Wook; Shin, Yong-Tai

    2012-02-01

    Renal actinomycosis is a rare infection caused by fungi of the genus Actinomyces. A 74-year-old male was admitted to our hospital because of gross hematuria with urinary symptoms and intermittent chills. Computed tomography of the abdomen showed thrombosis in the left renal vein and diffuse, heterogeneous enlargement of the left kidney. After nephrectomy, sulfur granules with chronic suppurative inflammation were seen microscopically, and the histopathological diagnosis was renal actinomycosis. Our case is the first report of renal actinomycosis with renal vein thrombosis.

  2. Portal vein thrombosis in patients with cirrhosis

    DEFF Research Database (Denmark)

    von Köckritz, Leona; De Gottardi, Andrea; Trebicka, Jonel

    2017-01-01

    Portal vein thrombosis (PVT) is frequent in patients with liver cirrhosis and possible severe complications such as mesenteric ischemia are rare, but can be life-threatening. However, different aspects of clinical relevance, diagnosis and management of PVT are still areas of uncertainty and inves......Portal vein thrombosis (PVT) is frequent in patients with liver cirrhosis and possible severe complications such as mesenteric ischemia are rare, but can be life-threatening. However, different aspects of clinical relevance, diagnosis and management of PVT are still areas of uncertainty...

  3. Postpartum Ovarian Vein Thrombophlebitis with Staphylococcal Bacteremia

    Science.gov (United States)

    Parino, Eduardo; Mulinaris, Eric; Saccomano, Edgardo; Gallo, Juan Cruz; Kohan, Gabriel

    2015-01-01

    A 34-year-old female patient presented with fever and right flank pain ten days after uncomplicated vaginal delivery. CT examination revealed right ovarian vein thrombosis and methicillin-resistant Staphylococcus aureus (MRSA) was isolated from blood cultures. No other source of bacteremia was found. Antibiotic therapy and anticoagulation with enoxaparin were instituted. Fourteen days after admission, she was discharged in good condition. Although a very uncommon complication after spontaneous vaginal delivery, septic ovarian vein thrombophlebitis should be suspected in cases of persistent puerperal fever when other diagnostic possibilities have been excluded. PMID:26221549

  4. Image Quality Enhancement Using the Direction and Thickness of Vein Lines for Finger-Vein Recognition

    Directory of Open Access Journals (Sweden)

    Young Ho Park

    2012-10-01

    Full Text Available On the basis of the increased emphasis placed on the protection of privacy, biometric recognition systems using physical or behavioural characteristics such as fingerprints, facial characteristics, iris and finger-vein patterns or the voice have been introduced in applications including door access control, personal certification, Internet banking and ATM machines. Among these, finger-vein recognition is advantageous in that it involves the use of inexpensive and small devices that are difficult to counterfeit. In general, finger-vein recognition systems capture images by using near infrared (NIR illumination in conjunction with a camera. However, such systems can face operational difficulties, since the scattering of light from the skin can make capturing a clear image difficult. To solve this problem, we proposed new image quality enhancement method that measures the direction and thickness of vein lines. This effort represents novel research in four respects. First, since vein lines are detected in input images based on eight directional profiles of a grey image instead of binarized images, the detection error owing to the non-uniform illumination of the finger area can be reduced. Second, our method adaptively determines a Gabor filter for the optimal direction and width on the basis of the estimated direction and thickness of a detected vein line. Third, by applying this optimized Gabor filter, a clear vein image can be obtained. Finally, the further processing of the morphological operation is applied in the Gabor filtered image and the resulting image is combined with the original one, through which finger-vein image of a higher quality is obtained. Experimental results from application of our proposed image enhancement method show that the equal error rate (EER of finger-vein recognition decreases to approximately 0.4% in the case of a local binary pattern-based recognition and to approximately 0.3% in the case of a wavelet transform

  5. The Use Of The VEINES-QOL/Sym Questionnaire In Patients Operated For Varicose Veins

    Directory of Open Access Journals (Sweden)

    Migdalski Łukasz

    2015-10-01

    Full Text Available Venous insufficiency is a common, chronic disease that affects nearly half of the population in highly developed countries. The vast majority of affected patients suffer from varicose veins (VV. Recently, the priority in medicine has been patient satisfaction with treatment and high quality of life. Therefore, disease-specific questionnaires that measure quality of life have been developed. One of these is VEINES-QOL/Sym with two subscales that assess quality of life and disease symptoms. To date, it has been used to examine patients with venous ulcers and thrombosis. No data are available concerning the use of VEINES to assess patients after VV surgery.

  6. An unusual case: right proximal ureteral compression by the ovarian vein and distal ureteral compression by the external iliac vein

    Directory of Open Access Journals (Sweden)

    Halil Ibrahim Serin

    2015-12-01

    Full Text Available A 32-years old woman presented to the emergency room of Bozok University Research Hospital with right renal colic. Multidetector computed tomography (MDCT showed compression of the proximal ureter by the right ovarian vein and compression of the right distal ureter by the right external iliac vein. To the best of our knowledge, right proximal ureteral compression by the ovarian vein together with distal ureteral compression by the external iliac vein have not been reported in the literature. Ovarian vein and external iliac vein compression should be considered in patients presenting to the emergency room with renal colic or low back pain and a dilated collecting system.

  7. Epithelioid hemangioendothelioma of right innominate vein mimics a teratoma

    Science.gov (United States)

    Wan, Qi; Zhou, Jiaxuan; Yu, Yudong; Sun, Qingyu; Bao, Yingying; Lei, Qiang; Zou, Qiao; Deng, Yingshi; Li, Xinchun

    2017-01-01

    Abstract Rational: Epithelioid hemangioendothelioma (EHE) is a rare neoplasm commonly known to arise from the soft tissue, lung, and liver. EHE arising from right innominate vein (RIV) has scarcely been reported in English literature. Patient concerns: Herein, we present a rare case of EHE of RIV in a 51-year-old woman with right-lower chest pain for 4 days. Computed tomography of the chest revealed a spherical mass with calcification and fatty foci located in the anterior mediastinum, thus a presumptive diagnosis of teratoma was made. Diagnoses, interventions, and outcomes: Video-assisted thoracoscopic explorations and resection of mediastinal tumor were then performed. The pathological examination showed that the tumor was EHE. Postoperative radiotherapy was delivered to the patient. Pulmonary metastases were found by chest CT a year after surgery. Lessons: A diagnosis of EHE might be considered, when a mediastinal tumor closely related to veins showing intratumoral calcification and obvious enhancement, despite the presence of a clear boundary and visible fat content. PMID:28248868

  8. Relations of Facial Nerve With Retromandibular Vein in Human Fetuses.

    Science.gov (United States)

    Elvan, Özlem; Gilan, Yağmurhan; Beger, Orhan; Bobuş, Alev; Tezer, Mesut; Aktekin, Mustafa

    2017-06-01

    The relationship of facial nerve (FN) and its branches with the retromandibular vein (RMV) has been described in adults, whereas there is no data in the literature regarding this relationship in fetuses. The study was conducted to evaluate the anatomic relationships of these structures on 61 hemi-faces of fetuses with a mean age of 26.5 ± 4.9 weeks with no visible facial abnormalities. The FN trunk was identified at its emergence at the stylomastoid foramen. It was traced till its ramification within the parotid gland. In 46 sides, FN trunk ramified before crossing RMV and ran lateral to it, while in 8 sides FN trunk ramified on the lateral aspect of the RMV. In 3 sides, FN trunk ramified after crossing the RMV at its medial aspect. In only 1 side, FN trunk trifurcated as superior, middle, and inferior divisions and RMV lied anterior to FN trunk, lateral to superior division, medial to middle and inferior divisions. In 2 sides, FN trunk bifurcated as superior and inferior divisions. Retromandibular vein was located anterior to FN trunk, medial to superior division, lateral to inferior division in both of them. In 1 side, RMV ran medial to almost all branches, except the cervical branch of FN. Variability in the relationship of FN and RMV in fetuses as presented in this study is thought to be crucial in surgical procedures particularly in early childhood.

  9. Crystal science fundamentals

    OpenAIRE

    Ramachandran, V.; Halfpenny, PJ; Roberts, KJ

    2017-01-01

    The fundamentals of crystal science notably crystallography, crystal chemistry, crystal defects, crystal morphology and the surface chemistry of crystals are introduced with particular emphasis on organic crystals.

  10. Endovascular Radiofrequency Ablation for Varicose Veins

    Science.gov (United States)

    2011-01-01

    Executive Summary Objective The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and cost–effectiveness of endovascular radiofrequency ablation (RFA) for the treatment of primary symptomatic varicose veins. Background The Ontario Health Technology Advisory Committee (OHTAC) met on August 26th, 2010 to review the safety, effectiveness, durability, and cost-effectiveness of RFA for the treatment of primary symptomatic varicose veins based on an evidence-based review by the Medical Advisory Secretariat (MAS). Clinical Condition Varicose veins (VV) are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins). Symptoms typically affect the lower extremities and include (but are not limited to): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad

  11. Pressure Transducer Locations

    Data.gov (United States)

    National Aeronautics and Space Administration — Files are located here, defining the locations of the pressure transducers on the HIRENASD model. These locations also correspond to the locations that analysts...

  12. Varicose Veins: Role of Mechanotransduction of Venous Hypertension

    Science.gov (United States)

    Atta, Hussein M.

    2012-01-01

    Varicose veins affect approximately one-third of the adult population and result in significant psychological, physical, and financial burden. Nevertheless, the molecular pathogenesis of varicose vein formation remains unidentified. Venous hypertension exerted on veins of the lower extremity is considered the principal factor in varicose vein formation. The role of mechanotransduction of the high venous pressure in the pathogenesis of varicose vein formation has not been adequately investigated despite a good progress in understanding the mechanomolecular mechanisms involved in transduction of high blood pressure in the arterial wall. Understanding the nature of the mechanical forces, the mechanosensors and mechanotransducers in the vein wall, and the downstream signaling pathways will provide new molecular targets for the prevention and treatment of varicose veins. This paper summarized the current understanding of mechano-molecular pathways involved in transduction of hemodynamic forces induced by blood pressure and tries to relate this information to setting of venous hypertension in varicose veins. PMID:22489273

  13. Varicose Veins: Role of Mechanotransduction of Venous Hypertension

    Directory of Open Access Journals (Sweden)

    Hussein M. Atta

    2012-01-01

    Full Text Available Varicose veins affect approximately one-third of the adult population and result in significant psychological, physical, and financial burden. Nevertheless, the molecular pathogenesis of varicose vein formation remains unidentified. Venous hypertension exerted on veins of the lower extremity is considered the principal factor in varicose vein formation. The role of mechanotransduction of the high venous pressure in the pathogenesis of varicose vein formation has not been adequately investigated despite a good progress in understanding the mechanomolecular mechanisms involved in transduction of high blood pressure in the arterial wall. Understanding the nature of the mechanical forces, the mechanosensors and mechanotransducers in the vein wall, and the downstream signaling pathways will provide new molecular targets for the prevention and treatment of varicose veins. This paper summarized the current understanding of mechano-molecular pathways involved in transduction of hemodynamic forces induced by blood pressure and tries to relate this information to setting of venous hypertension in varicose veins.

  14. Brain vein disorders in newborn infants

    NARCIS (Netherlands)

    Raets, Marlou; Dudink, Jeroen; Raybaud, Charles; Ramenghi, Luca; Lequin, Maarten; Govaert, Paul

    2015-01-01

    The brain veins of infants are in a complex phase of remodelling in the perinatal period. Magnetic resonance venography and susceptibility-weighted imaging, together with high-resolution Doppler ultrasound, have provided new tools to aid study of venous developmental anatomy and disease. This review

  15. Endovascular vein harvest: systemic carbon dioxide absorption.

    Science.gov (United States)

    Maslow, Andrew M; Schwartz, Carl S; Bert, Arthur; Hurlburt, Peter; Gough, Jeffrey; Stearns, Gary; Singh, Arun K

    2006-06-01

    Endovascular vein harvest (EDVH) requires CO(2) insufflation to expand the subcutaneous space, allowing visualization and dissection of the saphenous vein. The purpose of this study was to assess the extent of CO(2) absorption during EDVH. Prospective observational study. Single tertiary care hospital. Sixty patients (30 EDVH and 30 open-vein harvest) undergoing isolated coronary artery bypass graft surgery. Hemodynamic, procedural, and laboratory data were collected prior to (baseline), during, and at it the conclusion (final) of vein harvesting. Data were also collected during cardiopulmonary bypass (CPB). Data were compared by using t tests, analysis of variance, and correlation statistics when needed. There were significant increases in arterial CO(2) (PaCO(2), 35%) and decreases in pH (1.35%) during EDVH. These were associated with increases in heart rate, mean blood pressure, and cardiac output. Within the EDVH group, greater elevations (>10 mmHg) in PaCO2 were more likely during difficult harvest procedures, and these patients exhibited greater increase in heart rate. Elevated CO(2) persisted during CPB, requiring higher systemic gas flows and greater use of phenylephrine to maintain desired hemodynamics. EDVH was associated with systemic absorption of CO(2). Greater absorption was more likely in difficult procedures and was associated with greater hemodynamic changes requiring medical therapy.

  16. Puzzles in practice: splenic vein thrombosis.

    Science.gov (United States)

    McIntyre, Brittany; Marsh, Melanie; Walden, Jeffrey

    2016-06-01

    This report details a 58-year-old gentleman who presented to his outpatient primary care physician's clinic several times over four weeks for ongoing epigastric pain radiating into his left flank, dry heaving, and constipation. He was presumed to have gastritis at each visit and prescribed escalating doses of proton pump inhibitors. Due to the unrelenting pain, he eventually was admitted to the hospital and diagnosed with splenic vein thrombosis after computed tomography imaging of the abdomen. Our literature search revealed that pancreatic pathology is overwhelmingly the contributing factor to splenic vein thrombosis. Our patient had prominent collateral vasculature, suggesting that his splenic vein thrombosis was chronic in nature and likely the cause of his ongoing abdominal pain. Splenic vein thrombosis is an uncommon cause of abdominal pain, but one that should be included in the treating physician's differential diagnoses when abdominal pain is ongoing despite medical therapy. Although he had no evidence of initial findings on radiography, our patient was eventually diagnosed with biopsy-proven pancreatic cancer. Our case report demonstrates how patients presenting with persistent or worsening abdominal pain despite the use of proton pump inhibitors or other acid reducing agents and potential 'red flag' findings such as decreased appetite and weight loss should be worked up for other potential sources of abdominal pathology.

  17. A RARE VARIATION OF GREAT SAPHENOUS VEIN

    Directory of Open Access Journals (Sweden)

    Nakhate Manisha

    2014-11-01

    Full Text Available The venous system is more complex and variable than arterial system due to its frequent anatomical variations. This paper discusses the anatomy of the great saphenous vein and its variation observed in a male cadaver of around 60 years old.

  18. RETINAL VEIN OCCLUSIONS - A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Ramadevi

    2015-11-01

    Full Text Available Retinal vein occlusion is the most common retinal occlusive disorder encountered by opthalmologists and is usually associated with a variable amount of visual loss.The study was conducted over a period of 22 months, we performed a combined analysis of risk factors, clinical presentation, management and complication of these 51 patients

  19. Risk factors of thrombosis in abdominal veins

    Institute of Scientific and Technical Information of China (English)

    Amit Kumar Durra; Ashok Chacko; Biju George; Joseph Anjilivelil Joseph; Sukesh Chandran Nair; Vikram Mathews

    2008-01-01

    AIM: To estimate the prevalence of inherited and acquired thrombophilic risk factors in patients with abdominal venous thrombosis and to compare the risk factor profiles between Budd-Chiari syndromes (BCS) and splanchnic vein thrombosis (SVT).METHODS: In this retrospective study, 36 patients with abdominal venous thrombosis were studied.The patients were divided into Budd-Chiari group (hepatic vein, IVC thrombosis) and splanchnic venous thrombosis group (portal, splenic, superior mesenteric veins) based on the veins involved. Hereditary and acquired thrombophilic risk factors were evaluated in all patients.RESULTS: Twenty patients had SVT, 14 had BCS,and 2 had mixed venous thrombosis. Ten patients (28%) had hereditary and 10 patients (28%) acquired thrombophilic risk factors. The acquired risk factors were significantly more common in the SVT group (SVT vs BCS:45% vs 7%,x2=5.7,P=0.02) while hereditary risk factors did not show significant differences between the two groups (SVT vs BCS: 25%vs 36%, x2=0.46,P=0.7). Multiple risk factors were present in one (7%) patient with BCS and in 3 patients (15%) with SVT. No risk factors were identified in 57% of patients with BCS and in 45% of patients with SVT.CONCLUSION: Hereditary and acquired risk factors play an important role in the etiopathogenesis of abdominal venous thrombosis. Acquired risk factors are significantly more common in SVT patients while hereditary factors are similar in both groups.

  20. Gene Variants Associated With Deep Vein Thrombosis

    NARCIS (Netherlands)

    Bezemer, Irene D.; Bare, Lance A.; Doggen, Carine J.M.; Arellano, Andre R.; Tong, Carmen; Rowland, Charles M.; Catanese, Joseph; Young, Bradford A.; Reitsma, Pieter H.; Devlin, James J.; Rosendaal, Frits R.

    2008-01-01

    Context The genetic causes of deep vein thrombosis (DVT) are not fully understood. Objective To identify single-nucleotide polymorphisms (SNPs) associated with DVT. Design, Setting, and Patients We used 3 case-control studies of first DVT. A total of 19 682 gene-centric SNPs were genotyped in 44

  1. Small saphenous vein: where does reflux go?

    Directory of Open Access Journals (Sweden)

    Guillermo Gustavo Rossi

    2013-06-01

    Full Text Available BACKGROUND: The anatomy of small saphenous vein (SSV is very variable because of its complex embryological origin. SSV incompetence often causes reflux that goes to the perforating veins, sometimes not respecting the anatomical course. OBJECTIVE: To analyze differences in reflux direction and reentry in the SSV. METHODS: In this prospective, observational study, 60 lower limbs with SSV incompetence of 43 patients were assessed using a color Doppler ultrasound protocol. RESULTS: Reentry variations were grouped into four types and subtypes. Percentage results were: Type A, perforating veins on the medial side = 25/60 cases (41.66%; subtypes: Cockett, Sherman, paratibial and vertex; Type B, lateral malleolus and perforating veins on the lateral side (fibular 17-26 cm = 15/60 cases (25%; subtypes: fibular and malleolus; Type C, two branches = 19/60 cases (31.66%; subtypes: gastrocnemius and Cockett, gastrocnemius and malleolus, and/or fibular, Cockett and malleolus, Cockett-vertex and fibular; Type D, reflux in the superficial system = 1/60 cases (1.66%. CONCLUSION: On most of the lower limbs assessed, reflux did not follow the classical anatomic course. Our findings demonstrated a high degree of variation in reflux/reentry, but no SSV anatomical variations. Reflux seems to, either look for the most accessible anatomical connection for reentry or be originated in the distal area and then reach the SSV.

  2. Evaluation of left renal vein entrapment using multidetector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Poyraz, Ahmet K.; Onur, Mehmet R. [Dept. of Radiology, Firat Univ. School of Medicine, Elazig (Turkey)], e-mail: akursadpoyraz@yahoo.com.tr; Firdolas, Fatih [Dept. of Urology, Firat Univ. School of Medicine, Elazig (Turkey); Kocakoc, Ercan [Dept. of Radiology, Bezmialem Vakif Univ., School of Medicine, Istanbul (Turkey)

    2013-03-15

    Background: Nutcracker syndrome, also called left renal vein entrapment syndrome, is a cause of non-glomerular hematuria with difficulties in diagnosis. Multidetector computed tomography (MDCT) is a powerful tool to prevent unnecessary diagnostic procedures. Purpose: To retrospectively determine the prevalence of nutcracker phenomenon and nutcracker syndrome seen in MDCT in consecutive patients. Material and Methods: The institutional review board approved the study and waived the requirement for informed consent. Abdominal contrast-enhanced MDCT scans were reviewed from 1000 consecutive patients. MDCT scan assessment included renal vein diameter measurements and evaluation for the presence of anterior or posterior left renal vein entrapment. Electronic medical records and urine analysis reports of patients with left renal vein entrapment were reviewed. Student's t test was used to assess differences in renal vein diameter in patients with left renal vein entrapment. Results: Left renal vein entrapment was observed in 10.9% (109), retroaortic left renal vein in 6.5% (65), entrapment of left renal vein between superior mesenteric artery and aorta in 4.1% (41), and circumaortic left renal vein in 0.3% (3) of patients. Mean diameters of right (8.8 {+-} 1.9 mm) and unentrapped left (8.9 {+-} 1.8 mm) renal veins were not significantly different (P = 0.1). The mean diameter of anterior entrapped left renal veins (10.3 {+-} 2 mm) was significantly greater (P = 0.04) than contralateral renal veins (8.6 {+-} 2.1 mm) in their widest portion. In 8.8% of patients with the left renal vein entrapment, urine analysis showed isomorphic hematuria or proteinuria with no other known cause. Varicocele and pelvic congestion were seen in 5.5% of patients with the left renal vein entrapment. Conclusion: Left renal vein entrapment is not a rare entity and renal nutcracker phenomenon might be underdiagnosed.

  3. 双程腔内倍频激光器的谐波晶体腔内位置的理论研究%The Theory Research on the Location of a Frequency Doubling Crystal in a Double-pass Intracavity Frequency Doubling Laser

    Institute of Scientific and Technical Information of China (English)

    程一斌

    2000-01-01

    In this paper, the location of a frequency doubling crystal in a double-pass intra cavity frequency doubling and plano- concave confignration' s laser whose output was inone direc tion was analyzed in theory, and the formula of the suitable space between the frequency doubling crystal and the fiat mirror was obtained.%从理论上分析了平-凹腔结构的双程谐波、单方向输出的腔内谐波激光器的谐 波晶体腔内位置的选择,获得了谐波晶体与全反射镜的合理间距的解析式。

  4. Image Quality Enhancement Using the Direction and Thickness of Vein Lines for Finger-Vein Recognition

    OpenAIRE

    Young Ho Park; Kang Ryoung Park

    2012-01-01

    On the basis of the increased emphasis placed on the protection of privacy, biometric recognition systems using physical or behavioural characteristics such as fingerprints, facial characteristics, iris and finger‐vein patterns or the voice have been introduced in applications including door access control, personal certification, Internet banking and ATM machines. Among these, finger‐vein recognition is advantageous in that it involves the use of inexpensive and small devices that are diffic...

  5. Adventitial cystic disease of the common femoral vein presenting as deep vein thrombosis

    Directory of Open Access Journals (Sweden)

    Young-Kyun Kim

    2016-07-01

    Full Text Available Adventitial cystic disease of the common femoral vein is a rare condition. We herein report the case of a 50-year-old woman who presented with painless swelling in her left lower leg that resembled deep vein thrombosis. She underwent femoral exploration and excision of the cystic wall. The presentation, investigation, treatment, and pathology of this condition are discussed with a literature review.

  6. Coarse muscovite veins and alteration deep in the Yerington batholith, Nevada: insights into fluid exsolution in the roots of porphyry copper systems

    Science.gov (United States)

    Runyon, Simone E.; Steele-MacInnis, Matthew; Seedorff, Eric; Lecumberri-Sanchez, Pilar; Mazdab, Frank K.

    2017-04-01

    Veins and pervasive wall-rock alteration composed of coarse muscovite±quartz±pyrite are documented for the first time in a porphyritic granite at Luhr Hill in the Yerington District, Nevada. Coarse muscovite at Luhr Hill occurs at paleodepths of 6-7 km in the roots of a porphyry copper system and crops out on the scale of tens to hundreds of meters, surrounded by rock that is unaltered or variably altered to sodic-calcic assemblages. Coarse muscovite veins exhibit a consistent orientation, subvertical and N-S striking, which structurally restores to subhorizontal at the time of formation. Along strike, coarse muscovite veins swell from distal, millimeter-thick muscovite-only veinlets to proximal, centimeter-thick quartz-sulfide-bearing muscovite veins. Crosscutting relationships between coarse muscovite veins, pegmatite dikes, and sodic-calcic veins indicate that muscovite veins are late-stage magmatic-hydrothermal features predating final solidification of the Luhr Hill porphyritic granite. Fluid inclusions in the muscovite-quartz veins are high-density aqueous inclusions of 3-9 wt% NaCl eq. and alteration differs in texture, composition, and process of formation from sericite at shallower levels of the hydrothermal system. Although the definition of greisen is controversial, we suggest that coarse muscovite alteration is more similar to alteration in greisen-type Sn-W-Mo districts worldwide than to sericitic alteration at higher levels of porphyry copper systems. The fluids that form coarse muscovite veins and alteration in the roots of porphyry copper systems are distinct from fluids that formed copper ore or widespread, shallower, acidic alteration. We propose that this style of veins and alteration at Luhr Hill represents degassing of moderate volumes of overpressured hydrothermal fluid during late crystallization of deep levels of the Yerington batholith.

  7. Successful correction of unroofed coronary sinus with pulmonary vein stenosis.

    Science.gov (United States)

    Li, Yang; An, Qi; Zhang, Eryong

    2012-07-01

    We present a case of an infant with an unroofed coronary sinus associated with a persistent left superior vena cava draining into the left atrium, right superior pulmonary vein stenosis, an atretic left superior pulmonary vein and a double-outlet right ventricle. For pulmonary vein stenosis and atresia, we used a sutureless technique with an autologous pericardial patch to create a neoatrium.

  8. Stable Isotopic Composition for Hydrothermal Vein Deposits, Southeastern Korea

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@The southeast of Korea has attracted considerable attention in the geologic community because of its extensive igneous activity and associated mineralizations from the Late Cretaceous to the Early Tertiary (Cu, Pb-Zn, W-Mo, Bi and Au-Ag hydrothermal-vein deposits, porphyry, skarn and altered clay deposits). The southeast of Korea is composed of Cretaceous sedimentary Gyeongsan basin, volcanic and plutonic rocks. Most of the mines are either closed or incapable of producing more ores because of their poor reserves. The south of the Gyeongsang basin is famous for its hydrothermal altered clay deposits associated with volcanism. In order to locate more metal resources, many researches have been conducted into the gold-silver mineralization within hydrothermai-altered deposits in the past several years. The age of plutonism ranges from 112 Ma to 44 Ma, and that of volcanism from 74 Ma to 47 Ma.

  9. Neoproterozoic Cana Brava chrysotile deposit (Goiás, Brazil): Geology and geochemistry of chrysotile vein formation

    Science.gov (United States)

    Biondi, João Carlos

    2014-01-01

    The Cana Brava chrysotile asbestos deposit of Goiás, Brazil, contains approximately 150 Mt of ore with an average of 3.5 wt.% of cross-fiber chrysotile and lies in the differentiated, mafic-ultramafic Neoproterozoic Cana Brava complex. This complex was formed at approximately 0.79 Ga and metamorphosed at 0.77 to 0.76 and 0.63 Ga. The 0.77 to 0.76 Ga metamorphic event was a high-grade one that transformed the mafic and ultramafic rocks into meta-peridotites and meta-pyroxenites. The low-grade 0.63 Ga metamorphism allowed the formation of black, red and brown serpentinite, graphitic, magnesite-rich talc serpentinite, and rodingite, which became folded and foliated. At the end of the 0.63 Ga metamorphism, black serpentinites were oxidized to form red serpentinites, the main type of serpentinite that outcrops today at the Cana Brava mineralized region. Post-metamorphic fluids reactivated the process of serpentinization, thereby generating massive green serpentinite from the red. Green formed on the most fractured zones, and double red and green reaction rims formed on the sides of the veins located outside the green serpentinite zones. This process did not cause significant variation in the volume of the rocks and resulted in a strongly reducing system thanks to the loss of Fe2O3 and iron and the subsequent crystallization of magnetite within veinlets and altered rocks. Low angle shear, developed under brittle conditions, caused hydraulic fracturing and the generation of oversaturated, oxidizing fluids that crystallized the cross-fiber chrysotile inside open fractures. Very densely fractured zones with fractures filled with cross-fiber chrysotile constitute the ore that is mined at present.

  10. Balloon occlusion versus wedged hepatic venography using iodinated contrast for targeting the portal vein during TIPS.

    Science.gov (United States)

    Caporossi, J-M; Vidal, V; Jacquier, A; Reyre, A; Flavian, A; Muller, C; Gaubert, J-Y; Bartoli, J-M; Moulin, G; Varoquaux, A

    2015-04-01

    To assess the efficacy, safety and gain in procedure time of the technique of balloon occlusion hepatic venography with iodinated contrast used to target the portal vein during TIPS. The technique is assessed versus wedged hepatic venography. Fifty-eight TIPS were prospectively included. The portal vein was located in 30 cases by the wedged hepatic venography (group 1) and in 28 cases by balloon occlusion hepatic venography (group 2). To compare both techniques a "portogram quality" score was defined using a 5 points scale. The time required to achieve portal puncture was also recorded. The complications of both procedures were assessed and classified in groups as intrahepatic hematoma or intraperitoneal hemorrhage. The right portal vein was visualized in a significantly higher number of patients using balloon than with wedged retrograde venography 71.3% (20/28) versus 13.3% (4/30) respectively (P=0.002). The quality score for the portogram was significantly higher for balloon hepatic venography 2.21 than for wedged hepatic venography 1.07 (P=0.002). The mean time required to puncture the portal vein was significantly shorter when the right branch of the portal vein was visualized 21 min versus 33.5 min (P=0.046). We recorded one intrahepatic hematoma (3.3%) and 4 intraperitoneal hemorrhage (13.3%) secondary to wedged hepatic venography. There were no complications with balloon occlusion hepatic venography (P=0.053). The use of balloon occlusion hepatic venography improves the quality of the retrograde portal venography to target the portal vein and decreases procedure time. The balloon technique is also burdened with fewer complications than the standard wedged hepatic venography. Copyright © 2014 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  11. Primary varicose veins: Frequency, clinical significance and surgical treatment

    Directory of Open Access Journals (Sweden)

    Vasić Dragan M.

    2004-01-01

    Full Text Available INTRODUCTION According to the definition of the World Health Organization, varicose veins represent abnormally enlarged superficial veins having baggy or cylindrical shape. The most frequent cause of primary varicose veins is the insufficiency of long saphenous vein (LSV, but especially the basin of its connection with femoral vein and perforating veins. OBJECTIVE The objectives of these investigations were: the determination of insufficiency incidence of SSV in cases of LSV insufficiency; the establishment of association of insufficiency of perforating veins of the basin of LSV and SSV; the study of the results of surgical treatment of insufficiency and varicosity of both short and long saphenous veins. METHODS In this study, 100 patients (66 women and 34 men, average age 52.1 years, with clinical symptoms showing the insufficiency and varicosity of long saphenous vein with no change of deep vein system were examined. Ultrasonographic examinations were made using Color Doppler probes - 7.5 and 3.75 MHz (Toshiba Corevison SSA 350 A; the development of incompetence of long saphenous vein (LSV and short saphenous vein (SSV at the level of the junction as well as other incompetent valves were examined. The reflux was defined as a retrograde flow of the duration longer than 0.5 seconds. RESULTS The insufficiency of short saphenous vein was determined by ultrasonographic examination in 34%, while the insufficiency of perforating veins in 80% of patients. 40% of patients were operated (33.3% of females, and 52.9% of males. The most frequent indications for surgical treatment of superficial veins insufficiency were: strong varicosities, clear symptoms and signs, superficial thrombophlebitis and conditions after superficial thrombophlebitis. Surgical treatment was applied in 16% of patients due to recurrence in the basin of long saphenous vein, and in 6% of cases because of the recurrence in the basin of short saphenous vein. Data analysis failed to

  12. [Pelvic vein thrombosis with elevated D-dimer level and normal ultrasound scan of the femoral vein].

    Science.gov (United States)

    Stenberg, Morten Roos; Tveskov, Claus

    2014-01-13

    A 17-year-old female presented with an isolated pelvic vein thrombosis (PVT) which was not visualised at the first compression ultrasound scan of the femoral vein. Isolated PVT should be suspected when the patient demonstrates the possible symptoms of a deep vein thrombosis with unilateral leg swelling extending to the groin and a negative compression ultrasound scan of the femoral vein. Supplemental ultrasound scan with Doppler flow, computed tomography or magnetic resonance venography are alternative diagnostic modalities if PVT is suspected.

  13. Treatment of recurrent varicose veins of the great saphenous vein by conventional surgery and endovenous laser ablation.

    NARCIS (Netherlands)

    Groenendael, L. van; Vliet, J.A. van der; Flinkenflogel, L.; Roovers, E.A.; Sterkenburg, S.M. van; Reijnen, M.M.P.J.

    2009-01-01

    OBJECTIVE: Varicose vein recurrence of the great saphenous vein (GSV) is a common, costly, and complex problem. The aim of the study was to assess feasibility of endovenous laser ablation (EVLA) in recurrent varicose veins of the GSV and to compare this technique with conventional surgical reinterve

  14. Giant Splenorenal Shunt in a Young Patient with Autoimmune Hepatitis/Primary Biliary Cholangitis Overlap Syndrome and Portal Vein Thrombosis

    Directory of Open Access Journals (Sweden)

    F. Chegai

    2017-01-01

    Full Text Available We present a case of giant Splenorenal Shunt (SRS associated with portal vein thrombosis in a 37-year-old woman with a twelve-year history of autoimmune hepatitis/primary biliary cholangitis overlap syndrome. At the moment of the CT examination laboratory tests showed creatinine 1.5 mg/dl, bilirubin 1.5 mg/dl, INR 3, and Na 145 mmol/l and the Model End-Stage Liver Disease score was 24. Extensive calcified thrombosis causing complete occlusion of the portal vein lumen and partially occluding the origin of the superior mesenteric vein was present and a small calcified thrombus in the Splenic Vein lumen was also evident. SRS was located among the spleen hilum and the left kidney with a maximum diameter of 3.25 cm and was associated with dilatation of left renal vein and inferior vena cava. After a multidisciplinary evaluation the patient was put on the Regional Liver Transplant waiting list and liver transplantation was performed successfully. Although portal vein thrombosis and SRS are common occurrences in cirrhotic patients, the impact in the natural history of the disease is still unclear. Careful management and accurate imaging protocols are essential in the evaluation of those patients.

  15. Primary leiomyosarcoma of saphenous vein presenting as deep venous thrombosis.

    Science.gov (United States)

    Fremed, Daniel I; Faries, Peter L; Schanzer, Harry R; Marin, Michael L; Ting, Windsor

    2014-12-01

    Only a small number of venous leiomyosarcomas have been previously reported. Of these tumors, those of saphenous origin comprise a minority of cases. A 59-year-old man presented with symptoms of deep vein thrombosis and was eventually diagnosed with primary leiomyosarcoma of great saphenous vein origin. The tumor was treated with primary resection and femoral vein reconstruction with autologous patch. Although extremely rare, saphenous leiomyosarcoma can present as deep vein thrombosis. Vascular tumors should be included in the differential diagnosis of atypical extremity swelling refractory to conventional deep vein thrombosis management.

  16. Safety and efficacy of cryopreserved homologous veins for venous reconstruction in pancreatoduodenectomy.

    Science.gov (United States)

    Yamamoto, Masaki; Akamatsu, Nobuhisa; Aoki, Taku; Sakamoto, Yoshihiro; Tamura, Sumihito; Hasegawa, Kiyoshi; Kokudo, Norihiro

    2017-02-01

    There are several techniques for reconstructing the portal vein-superior mesenteric vein during pancreatoduodenectomy. The aim of the present study was to present our results with portal vein-superior mesenteric vein reconstruction using cryopreserved homologous veins during pancreatoduodenectomy for patients with pancreatic head cancer. Patients who underwent pancreatoduodenectomy for pancreatic head cancer were reviewed retrospectively. In patients with portal vein-superior mesenteric vein resection, the detailed method of reconstruction and clinical outcomes were reviewed. Clinical characteristics, patient survival, and portal vein-superior mesenteric vein patency were compared between those with and without homologous vein grafts. Factors affecting the patency of reconstructed veins were assessed by univariate analysis. Among 144 patients undergoing pancreatoduodenectomy, portal vein-superior mesenteric vein resection was performed in 36 patients (25%); 18 (50%) underwent reconstruction with homologous veins, and the other 18 (50%) underwent reconstruction without homologous veins. The extent of portal vein-superior mesenteric vein involvement, operative time, duration of clamping of portal vein-superior mesenteric vein, intraoperative blood loss, and length of the venous resection were greater (P ≤ .013 each) in those with homologous vein grafts. There was no significant difference in postoperative morbidity/mortality, patient survival, or portal vein-superior mesenteric vein patency. The 1- and 2-year overall patency of portal vein-superior mesenteric vein was 76% and 71%, respectively, while the 2-year patencies were 67% and 67% in those with homologous veins and 87% and 73% in those without homologous veins without difference between the groups. Circumferential resection and pathologic portal vein-superior mesenteric vein involvement were associated with the patency of the reconstructed vein (P = .002 and P = .028, resp). Use of homologous venous

  17. A novel multiscale topo-morphometric approach for separating arteries and veins via pulmonary CT imaging

    Science.gov (United States)

    Saha, Punam K.; Gao, Zhiyun; Alford, Sara; Sonka, Milan; Hoffman, Eric

    2009-02-01

    Distinguishing arterial and venous trees in pulmonary multiple-detector X-ray computed tomography (MDCT) images (contrast-enhanced or unenhanced) is a critical first step in the quantification of vascular geometry for purposes of determining, for instance, pulmonary hypertension, using vascular dimensions as a comparator for assessment of airway size, detection of pulmonary emboli and more. Here, a novel method is reported for separating arteries and veins in MDCT pulmonary images. Arteries and veins are modeled as two iso-intensity objects closely entwined with each other at different locations at various scales. The method starts with two sets of seeds -- one for arteries and another for veins. Initialized with seeds, arteries and veins grow iteratively while maintaining their spatial separation and eventually forming two disjoint objects at convergence. The method combines fuzzy distance transform, a morphologic feature, with a topologic connectivity property to iteratively separate finer and finer details starting at a large scale and progressing towards smaller scales. The method has been validated in mathematically generated tubular objects with different levels of fuzziness, scale and noise. Also, it has been successfully applied to clinical CT pulmonary data. The accuracy of the method has been quantitatively evaluated by comparing its results with manual outlining. For arteries, the method has yielded correctness of 81.7% at the cost of 6.7% false positives and 11.6% false negatives. Our method is very promising for automated separation of arteries and veins in MDCT pulmonary images even when there is no mark of intensity variation at conjoining locations.

  18. Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy – Case report

    Directory of Open Access Journals (Sweden)

    Jianlin Tang

    2014-12-01

    Conclusion: The lessons we learned are (1 Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2 Synthetic graft is an alternative for internal jugular vein graft. (3 Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4 It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival.

  19. Augmented reality based real-time subcutaneous vein imaging system.

    Science.gov (United States)

    Ai, Danni; Yang, Jian; Fan, Jingfan; Zhao, Yitian; Song, Xianzheng; Shen, Jianbing; Shao, Ling; Wang, Yongtian

    2016-07-01

    A novel 3D reconstruction and fast imaging system for subcutaneous veins by augmented reality is presented. The study was performed to reduce the failure rate and time required in intravenous injection by providing augmented vein structures that back-project superimposed veins on the skin surface of the hand. Images of the subcutaneous vein are captured by two industrial cameras with extra reflective near-infrared lights. The veins are then segmented by a multiple-feature clustering method. Vein structures captured by the two cameras are matched and reconstructed based on the epipolar constraint and homographic property. The skin surface is reconstructed by active structured light with spatial encoding values and fusion displayed with the reconstructed vein. The vein and skin surface are both reconstructed in the 3D space. Results show that the structures can be precisely back-projected to the back of the hand for further augmented display and visualization. The overall system performance is evaluated in terms of vein segmentation, accuracy of vein matching, feature points distance error, duration times, accuracy of skin reconstruction, and augmented display. All experiments are validated with sets of real vein data. The imaging and augmented system produces good imaging and augmented reality results with high speed.

  20. Clinical Features of Primary Vein Grafts in Free Tissue Transfers

    Directory of Open Access Journals (Sweden)

    Mitsuru Nemoto

    2015-01-01

    Full Text Available The outcomes of free tissue transfers combined with vein grafts have been inconsistent, and discussions continue regarding their appropriate use. Of the 142 free tissue transfers that we performed from January 2004 to December 2011, we retrospectively analyzed 15 consecutive patients who underwent free tissue transfers in combination with vein grafts. Etiologies included trauma (8 patients, infection (4, and tumor (3. Types of free tissue transfers were fibula (4, anterolateral thigh (3, groin (3, jejunum (3, latissimus dorsi (1, and dorsal pedis (1. Vein grafts were used for the artery (6, vein (2, or both (7. The donor veins were the saphenous vein (12 and the external jugular vein (3. The mean length of the grafted veins was 10.8 cm (range: 4–18 cm. Even though complications of congestion occurred in 2 patients, these flaps survived by reexploration. The flap success rate was 15 of 15 (100% of vein grafted free flaps versus 124 of 127 (97.6% of free flaps not requiring vein grafts. To improve the success rate of free tissue transfers combined with vein grafts, securing healthy recipient vessels, meticulous surgical handling, a reliable vascular anastomosis technique, and strict postoperative monitoring are crucial.

  1. A pilot/introducer needle for central vein cannulation.

    Science.gov (United States)

    Suzuki, T; Kanazawa, M; Kinefuchi, Y; Fukuyama, H; Takiguchi, M; Yamamoto, M; Abe, K; Okuda, Y

    1995-12-01

    A kit for safe and easy insertion of a central vein cannula was devised. A small gauge (22 gauge) metal pilot needle was equipped with a Y-shaped hub which had a side-port to accept a small gauge (0.46 mm) Seldinger guide wire. Once the needle reached the vein, guidewire was threaded in through the side-port. There was no need to remove the pilot needle and no need to repeat vein puncture with a larger-bore needle. Three puncture methods were used with the kit: (1) the central approach via the internal jugular vein, (2) the supraclavicular approach via the junction of the internal jugular vein and subclavian vein, and (3) the infraclavicular approach via the subclavian vein. Each method was used on 20 patients, for total of 60 patients, with a high success rate. Less than 3 minutes were required from puncture to catheter insertion. No serious complications were encountered.

  2. Absent right superior caval vein in situs solitus

    DEFF Research Database (Denmark)

    Lytzen, Rebekka; Sundberg, Karin; Vejlstrup, Niels

    2015-01-01

    no postnatal complications. All children were found to have healthy hearts at follow-up. CONCLUSIONS: In all cases, the findings proved to be a benign condition with no clinical manifestations or complications. Although isolated absent right superior caval vein does not seem to affect the outcome, associated......Introduction In up to 0.07% of the general population, the right anterior cardinal vein obliterates and the left remains open, creating an absent right superior caval vein and a persistent left superior caval vein. Absent right superior caval vein is associated with additional congenital heart...... disease in about half the patients. We wished to study the consequences of absent right superior caval vein as an incidental finding on prenatal ultrasonic malformation screening. Material and methods This is a retrospective case series study of all foetuses diagnosed with absent right superior caval vein...

  3. [Treatment of renal vein thrombosis associated with nephrotic syndrome].

    Science.gov (United States)

    Funami, M; Takaba, T; Tanaka, H; Murakami, A; Kadokura, M; Hori, G; Ishii, J

    1988-06-01

    Renal vein thrombosis is a rare entity in which true incidence is unknown. The disease occurs most frequently in patients with nephrotic syndrome, but it also can occur in the presence of other hypercoagulable state. Two cases of renal vein thrombosis with nephrotic syndrome which were treated by thrombectomy are reported here. One patient was successfully treated by renal vein and inferior vena cava thrombectomy before developing severe pulmonary embolism. The other was treated by renal vein thrombectomy by which fatal shock was able to be prevented. In those cases, immediate operation was indicated, primarily to prevent additional, possibly fatal, pulmonary embolism and also to improve perfusion of the kidney. In the hope of salvaging the kidney, thrombectomy may be the treatment of choice for acute renal vein thrombosis, complication of pulmonary embolism and inferior vena cava thrombosis, right renal vein thrombosis without collateral flow and acute renal vein thrombosis with shock.

  4. The great brain versus vein debate.

    Science.gov (United States)

    Menon, Ravi S

    2012-08-15

    From the earliest fMRI experiments, it was quickly appreciated by those working with BOLD at high field that the signal change originated from visible veins whose spatial localization was relatively coarse ("the macrovasculature"), and smaller vessels ("the microvasculature") that were not individually visible in BOLD images. It was expected that a functional brain imaging technique that was predominantly sensitive to the macrovasculature would not have the same effective resolution as one sensitive to the microvasculature. Elimination of the venous signal and enhancement of the microvascular one offered the tantalizing ability to image columnar and lamellar structures in the brain and distinguished fMRI from its predecessor techniques. This article reviews a brief history of how these signal sources were first identified and separated and some of the controversy associated with the "brain versus vein" debate.

  5. Ovarian vein thrombosis in a polytrauma patient.

    Science.gov (United States)

    Toman, Emma; Beaven, Alastair; Balogun, Moji; Porter, Keith

    2015-12-18

    A young mother presented to a major trauma centre following a road traffic collision. Her admission CT traumagram demonstrated liver and renal lacerations, spinal and pelvic fractures with no abnormalities of the ovarian veins. Her inpatient course was uncomplicated other than a sustained, isolated raised C reactive protein. CT of the abdomen 1 week after injury demonstrated stable solid organ injuries and the additional, unexpected finding of a right ovarian vein thrombosis (OVT). A pragmatic approach was taken towards the management of the OVT given the haemorrhagic risk from her traumatic injuries. A multidisciplinary, consultant-led plan was made to slowly increase enoxaparin to a therapeutic dose under close surveillance and to then switch to warfarin following an outpatient consultation with a consultant haematologist. A MR venogram was performed after 3 months of anticoagulation, and this demonstrated complete resolution of the OVT and normal appearances of the ovary.

  6. Pulmonary vein stenosis: Etiology, diagnosis and management

    Institute of Scientific and Technical Information of China (English)

    Pablo Pazos-López; Cristina García-Rodríguez; Alba Guitián-González; Emilio Paredes-Galán; María ángel; De La Guarda álvarez-Moure; Marta Rodríguez-álvarez; José Antonio Baz-Alonso; Elvis Teijeira-Fernández; Francisco Eugenio Calvo-Iglesias; Andrés í?iguez-Romo

    2016-01-01

    Pulmonary vein stenosis(PVS) is rare condition characterized by a challenging diagnosis and unfavorable prognosis at advance stages. At present, injury from radiofrequency ablation for atrial fibrillation has become the main cause of the disease. PVS is characterized by a progressive lumen size reduction of one or more pulmonary veins that, when hemodynamically significant, may raise lobar capillary pressure leading to signs and symptoms such as shortness of breath, cough, and hemoptysis. Image techniques(transesophageal echocardiography, computed tomography, magnetic resonance and perfusion imaging) are essential to reach a final diagnosis and decide an appropriate therapy. In this regard, series from referral centers have shown that surgical and transcatheter interventions may improve prognosis. The purpose of this article is to review the etiology, assessment and management of PVS.

  7. Doppler spectral characteristics of infrainguinal vein bypasses

    DEFF Research Database (Denmark)

    Nielsen, Tina G; von Jessen, F; Sillesen, H

    1993-01-01

    With the aim of assessing the velocity profile of femoropopliteal and femorocrural vein bypasses, 128 patients undergoing infrainguinal vein bypass surgery entered a postoperative Duplex surveillance protocol, which included clinical assessment and Duplex scanning, using Doppler spectral analysis...... of arteriovenous fistulas the initially antegrade diastolic velocity was replaced by a retrograde flow within 3 months, whereas a forward flow in diastole was sustained in grafts with patent fistulas. Abnormal Duplex findings in 31 patients led to angiography and revision in 13 cases. Four revised grafts failed......, while nine remained patent at follow-up 1-12 months later. Ten (56%) of 18 non-revised bypasses with abnormal Duplex findings failed within 9 months compared to 1 (1%) of 76 bypasses with a normal velocity profile (p analysis provides...

  8. Endovenous radiofrequency ablation using stent-type electrode for varicose veins: an experimental study in goats

    Energy Technology Data Exchange (ETDEWEB)

    Won, Je Hwan; Han, Jae Ho; Oh, Chang Kwon [Ajou University Hospital, Suwon (Korea, Republic of); Kwak, Young Lan [Yonsei University College of Medicine, Seoul (Korea, Republic of); Park, Sung Il [Ulsan University GangNeung Asan Hospital, Gangeung (Korea, Republic of)

    2004-10-15

    The purpose of this study was to investigate the feasibility and the optimal conditions of radiofrequency (RF) ablation by using the stent-type electrode upon the saphenous vein of goats for the endovenous treatment of varicose veins. A self-expandable nitinol stent electrode (6 mm diameter, 2 cm length, cell size; 1.3 x 2 mm) was designed to expose the distal 1 cm segment to allow for contact with the venous wall. The proximal part of the electrode was connected to the RF generator by insulated copper wires located within the stent electrode introducer. Initially, to optimize the power setting, ablation of 6 saphenous veins in 3 goats was performed with power settings of 10, 20 and 30 W. Pull back rate of the electrode was 2 and 4 cm/min for each power level, respectively. The goats were sacrificed 4-6 weeks later and histologic examinations of the saphenous veins were done. For the second part of the experiment, RF ablation of 4 saphenous veins from 2 goats was done by applying the optimal power, based upon the first examination; these procedure was performed with variable pull back rates. Again, the goats were sacrificed 1-6 weeks later and histologic examinations were done. Endovenous ablation of the goat saphenous veins at 20 W caused complete obliteration without complication. There was incomplete occlusion at 10 W, and there were vessel perforation, extravasation, and adjacent tissue injury at 30 W. In second part of the study, the complete circumferential obliteration of the vein was demonstrated at a pull back rate of 1 cm/min and 3 cm/min with the power of 20 W. The stent-type electrode may be useful in endovenous RF ablation for treatment of varicose veins. For stents with a diameter of 6 mm, the optional combination of 20 W of power with a pull back rate of 1-3 cm/min produced the most favorable results. Further study and clinical investigations are warranted.

  9. Massive hydrothorax following subclavian vein catheterization

    OpenAIRE

    Omar, Hesham R.; fathy, Ahmad; Elghonemy, Mohamed; Rashad, Rania; Helal, Engy; Mangar, Devanand; Camporesi, Enrico

    2010-01-01

    Since the introduction of central venous catheterization for monitoring of the venous pressure, fluid infusion and hyperalimentation, the literature has been full of serious life-threatening complications. Of these complications is the false positioning of the central venous catheter and subsequent development of pleural effusion. In this report we are describing a case of iatrogenic massive pleural effusion following subclavian vein catheterization necessitating intercostal tube drainage and...

  10. A Location Privacy Aware Friend Locator

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Thomsen, Jeppe Rishede; Saltenis, Simonas

    2009-01-01

    to trade their location privacy for quality of service, limiting the attractiveness of the services. The challenge is to develop a communication-efficient solution such that (i) it detects proximity between a user and the user’s friends, (ii) any other party is not allowed to infer the location of the user...

  11. Central Vein Preservation in Critical Venous Access.

    Science.gov (United States)

    Davidson, J; Paul, A; Patel, S; Davenport, M; Ade-Ajayi, N

    2016-08-01

    Introduction The lack of suitable veins in children with critical central venous access requirements is a major obstacle to optimal care and is potentially life-threatening. We present outcomes following the use of vein-preserving (VP) surgical techniques, notably the sheath exchange for tunneled lines (SETL). Materials and Methods A retrospective, single observer analysis of a prospectively maintained departmental logbook as well as the medical records of patients. Two broad groups of central line replacements were identified; those inserted following removal of a previous line and a traditional "plastic-free" (PF) period and those exchanged without such an interval. Results Overall, 19 lines were directly exchanged during the study period and compared with 34 inserted after a PF period. Similar catheter life spans and infection rates were demonstrated in each group; 125 (range, 78-173) days in VP exchanges versus 122 (range, 70-175) days in PF replacements (p = 0.41). Line Sepsis resulting in removal or change of line occurred at 103 (range, 60-147) days in VP group versus 104 (range, 45-164) days in PF (p = 0.73). Conclusion For children with critical venous access requirements, direct line exchange procedures are a robust and reproducible means of vein preservation. The outcomes compare favorably with those following the more traditional removal, a PF period and reinsertion.

  12. Portal vein thrombosis related to Cassia angustifolia.

    Science.gov (United States)

    Soyuncu, Secgin; Cete, Yildiray; Nokay, Ali E

    2008-09-01

    Cassia angustifolia (Senna), used as a laxative, is a plant from the Fabaceae family. It includes hydroxyanthracene glycosides, also known as Senna Sennoside. These glycosides stimulate the peristalsis of the colon and alter colonic absorption and secretion resulting in fluid accumulation and expulsion. In the literature, there are reports illustrating the hepatotoxic effects of Cassia angustifolia but there is no report of portal vein thrombosis caused by Cassia Angustifolia. A 42-year-old woman was admitted to the emergency department with a five-day history of worsening epigastric pain, anorexia, episodic vomiting, and intermittent fever. She reported that she had boiled dried senna leaves she had bought from herbalists and drank approximately 200 mL daily for two years. Color Doppler screening found an echogen thrombus obliterating portal vein bifurcation and the right branch. The lumen was obstructed at this level and there was no blood flow through it. Treatment with thrombolytics was unsuccessful. Severe hepatotoxicity senna use is unusual. The cause of senna-related hepatotoxicity is unclear but could be explained by the exposure of the liver to unusual amounts of toxic metabolites of anthraquinone glycosides. Chronic use of Cassia angustifolia may rarely be associated with portal vein thrombosis.

  13. Laser photocoagulation for retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    K. A. Mirzabekova

    2015-03-01

    Full Text Available Retinal vein occlusion (RVO is one of the leading causes of permanent vision loss. In adults, central retinal vein occlusion (CRVO occurs in 1.8% while branch retinal vein occlusion (BRVO occurs in 0.2%. Treatment strategy and disease prognosis are determined by RVO type (ischemic/non-ischemic. Despite numerous studies and many current CRVO and BRVO treatment approaches, the management of these patients is still being debated. Intravitreal injections of steroids (triamcinolone acetate, dexamethasone and vascular endothelial growth factor (VEGF inhibitors (bevacizumab, ranibizumab were shown to be fairly effective. However, it is unclear whether anti-VEGF agents are reasonable in ischemic RVOs. Laser photocoagulation remains the only effective treatment of optic nerve head and/or retinal neovascularization. Laser photocoagulation is also indicated for the treatment of macular edema. Both threshold and sub-threshold photocoagulation may be performed. Photocoagulation performed with argon (514 nm, krypton (647 nm, or diode (810 nm laser for macular edema provides similar results (no significant differences. The treatment may be complex and include medication therapy and/or surgery. Medication therapy includes anti-aggregant agents and antioxidants, i.e., emoxypine which may be used in acute RVO as well as in post-thrombotic retinopathy. 

  14. Comparison between mechanical properties of human saphenous vein and umbilical vein

    Directory of Open Access Journals (Sweden)

    Hamedani Borhan

    2012-08-01

    Full Text Available Abstract Background As a main cause of mortality in developed countries, Coronary Artery Disease (CAD is known as silent killer with a considerable cost to be dedicated for its treatment. Coronary Artery Bypass Graft (CABG is a common remedy for CAD for which different blood vessels are used as a detour. There is a lack of knowledge about mechanical properties of human blood vessels used for CABG, and while these properties have a great impact on long-term patency of a CABG. Thus, studying these properties, especially those of human umbilical veins which have not been considered yet, looks utterly necessary. Methods Umbilical vein, as well as human Saphenous vein, are respectively obtained after cesarean and CABG. First, histological tests were performed to investigate different fiber contents of the samples. Having prepared samples carefully, force-displacement results of samples were rendered to real stress–strain measurements and then a fourth-order polynomial was used to prove the non-linear behavior of these two vessels. Results Results were analyzed in two directions, i.e. circumferentially and longitudinally, which then were compared with each other. The comparison between stiffness and elasticity of these veins showed that Saphenous vein’s stiffness is much higher than that of umbilical vein and also, it is less stretchable. Furthermore, for both vessels, longitudinal stiffness was higher than that of circumferential and in stark contrast, stretch ratio in circumferential direction came much higher than longitudinal orientation. Conclusion Blood pressure is very high in the region of aorta, so there should be a stiff blood vessel in this area and previous investigations showed that stiffer vessels would have a better influence on the flow of bypass. To this end, the current study has made an attempt to compare these two blood vessels’ stiffness, finding that Saphenous vein is stiffer than umbilical vein which is somehow as stiff as

  15. Fracture and vein characterization of a crystalline basement reservoir, central Yemen

    Science.gov (United States)

    Veeningen, R.; Grasemann, B.; Decker, K.; Bischoff, R.; Rice, A. H. N.

    2012-04-01

    The country of Yemen is located in the south-western part of the Arabian plate. The Pan-African basement found in western and central Yemen is highly deformed during the Proterozoic eon and is part of the Arabian-Nubian shield ANS (670-540Ma). This ANS is a result of the amalgamation of high-grade gneiss terranes and low-grade island arcs. The development of an extensive horst-and-graben system related to the breakup of Gondwana in the Mesozoic, has reactivated the Pan-African basement along NW-SE trending normal faults. As a result, younger Meosozoic marls, sandstones, clastics and limestones are unconformably overlying the basement. Some of these formations act as a source and/or reservoir for hydrocarbons. Due to fracturing of the basement, hydrocarbons have migrated horizontally into the basement, causing the crystalline basement to be a potential hydrocarbon reservoir. Unfortunately, little is known about the Pan-African basement in Central Yemen and due its potential as a reservoir, the deformation and oil migration history (with a main focus on the fracturing and veining history) of the basement is investigated in high detail. Representative samples are taken from 2 different wells from the Habban Field reservoir, located approximately 320 ESE of Sana'a. These samples are analysed using e.g. the Optical Microscope, SEM, EDX and CL, but also by doing Rb-Sr age dating, isotope analysis and fluid inclusion analysis. In well 1, the only lithology present is an altered gneiss with relative large (<5 cm diameter) multi-mineralic veins. In well 3, quartzite (top), gneiss (middle) and quartz porphyry's (middle) are intruded by a so called "younger" granitoid body (592.6±4.1Ma). All lithologies record polyphase systems of mineral veins. Pyrite and saddle dolomite in these veins have euhedral shapes, which means that they have grown in open cavities. Calcite is the youngest mineral in these veins, closing the vein and aborting the fluid flow. Fluid inclusions inside

  16. BBO晶体腔内位置对灯泵Cr:LiSAF激光器腔内倍频的影响的研究%The Research of the Location Effecting of BBO Crystal on the Output Energy of an Intracavity Frequency-doubled Flashlamp-pumped Cr:LiSAF Laser

    Institute of Scientific and Technical Information of China (English)

    陈长水; 赵柯; 王佩琳; 谢建平

    2000-01-01

    本文实验研究了由于色散引起的BBO晶体腔内位置对灯泵Cr:LiSAF激光器腔内倍频输出的影响,并从理论上获得了腔内倍频的BBO晶体的最佳位置为基波与谐波的位相差2π的整数倍,同时,考虑到容许的基波与谐波的位相差为±π/4时,对应基波和谐波波长分别为:900nm和450 nm处,腔内倍频的BBO晶体的位置调整范围为9.4 mm.%The location of BBO crystal in the cavity effecting the output energy in the intracavity frequency-doubling of a flashlamp-pumped Cr:LiSAF laser is researched.The benefit net phase shift due to dispersion between the fundamental and the harmonic wave beam in the air path between BBO crystal and the mirror M3 is a multiple of 2π. If the net phase shift ofπ/4 is allowed, this requires a BBO crystal movement of no more than 9.4 mm at the fundamental wave of 900 nm and the harmonic wave of 450 nm.

  17. Enhancement of the visibility of objects located below the surface of a scattering medium

    Science.gov (United States)

    Demos, Stavros

    2013-11-19

    Techniques are provided for enhancing the visibility of objects located below the surface of a scattering medium such as tissue, water and smoke. Examples of such an object include a vein located below the skin, a mine located below the surface of the sea and a human in a location covered by smoke. The enhancement of the image contrast of a subsurface structure is based on the utilization of structured illumination. In the specific application of this invention to image the veins in the arm or other part of the body, the issue of how to control the intensity of the image of a metal object (such as a needle) that must be inserted into the vein is also addressed.

  18. Enhancement of the visibility of objects located below the surface of a scattering medium

    Energy Technology Data Exchange (ETDEWEB)

    Demos, Stavros

    2013-11-19

    Techniques are provided for enhancing the visibility of objects located below the surface of a scattering medium such as tissue, water and smoke. Examples of such an object include a vein located below the skin, a mine located below the surface of the sea and a human in a location covered by smoke. The enhancement of the image contrast of a subsurface structure is based on the utilization of structured illumination. In the specific application of this invention to image the veins in the arm or other part of the body, the issue of how to control the intensity of the image of a metal object (such as a needle) that must be inserted into the vein is also addressed.

  19. Characters of fluid inclusions in quartz veins in pyroclastic rock of Budate Group, Hailar Basin

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-tao; LIU Li; GAO Yu-qiao; SHAO Hong-mei; SHEN Guang-zheng

    2004-01-01

    It was adopted that the fluorescence microscope, Gas-Flow Heating/Freezing System, Laser-Raman Spectroscopy, etc. are the multimedia techniques for analysing fluid inclusions of quartz veins in Budate Group, Hailar Basin.The results show that fluid inclusions in quartz veins are small (1 ~5 μm) monophase, two-phase (liquid+vapour)aqueous inclusions; the two-phase aqueous inclusions homogeniese to the liquid phase between 120 ~ 180℃, two Laser-Raman Spectroscopy show that both gas phase are enriched in CH4 (94.50% ~99.25% ) and C6H6 (0.75% ~2.70%), under these conditions, inclusions may have come from juvenile fliud followingly the quartz veins formation.While the quartz veins exhibiting different striking luminescence has been proved by cathodoluminescence, it would be belong to secondary hydrocarbon inclusions. The oil inclusions of this stage represent mainly the large scale of oil accumulation, located within the quartz microfracture.

  20. Non-cuffed dual lumen catheters in the external jugular veins versus other central veins for hemodialysis patients.

    Science.gov (United States)

    Moini, Majid; Rasouli, Mohammad R; Kenari, Mohammad Mahmoodzadeh; Mahmoodi, Hamid Reza

    2009-01-01

    To compare prospective between insertion of non-cuffed dual lumen catheter in the external jugular vein and other central veins for hemodialysis (HD), we studied 68 chronic dialysis patients randomly allocated into two groups: one with external jugular vein catheterization as access for HD and another with other central venous catheterization, internal jugular or subclavian vein. Our results showed there were no significant differences regarding successful cannulation, com-plications, total numbers of dialysis, development of pain and infection at the site of cannulation, patency rate of the catheters, and efficacy of hemodialysis between both groups. In addition, the patency of the catheter in the external jugular vein was not affected by previous cannulation of other central veins. In contrast, there was a significant correlation between numbers of attempts for cannulation in both groups and development of hematoma and infection, (pvein may be an alternative for other central veins for insertion of temporary non-cuffed hemodialysis catheter.

  1. Crystal Electrostatic Energy

    CERN Document Server

    Ivanchin, Alexander

    2010-01-01

    It has been shown that to calculate the parameters of the electrostatic field of the ion crystal lattice it sufficient to take into account ions located at a distance of 1-2 lattice spacings. More distant ions make insignificant contribution. As a result, the electrostatic energy of the ion lattice in the alkaline halide crystal produced by both positive and negative ions is in good agreement with experiment when the melting temperature and the shear modulus are calculated. For fcc and bcc metals the ion lattice electrostatic energy is not sufficient to obtain the observed values of these parameters. It is possible to resolve the contradiction if one assumes that the electron density is strongly localized and has a crystal structure described by the lattice delta - function. As a result, positive charges alternate with negative ones as in the alkaline halide crystal. Such delta-like localization of the electron density is known as a model of nearly free electrons.

  2. Location of foot arteries using infrared images

    Science.gov (United States)

    Villasenor-Mora, Carlos; González-Vega, Arturo; Martín Osmany Falcón, Antonio; Benítez Ferro, Jesús Francisco Guillemo; Córdova Fraga, Teodoro

    2014-11-01

    In this work are presented the results of localization of foot arteries, in a young group of participants by using infrared thermal images, these are the dorsal, posterior tibial and anterior tibial arteries. No inclusion criteria were considered, that causes that no strong statistical data about the influence of the age in the arterial localization. It was achieved to solve the confusion when veins present a heat distribution similar to the artery and in the position of this. it contributes to enhance the rate of location of arteries. In general it is possible to say that the use of infrared thermal images is a good technique to find the foot arteries and can be applied in its characterization in a future. The procedure proposed is a non-invasive technique, and in certain fashion does not requires specialized personnel to achieve locate the arteries. It is portable, safe, and relatively economical.

  3. Abdominal thromboses of splanchnic, renal and ovarian veins.

    Science.gov (United States)

    De Stefano, Valerio; Martinelli, Ida

    2012-09-01

    Thromboses of abdominal veins outside the iliac-caval axis are rare but clinically relevant. Early deaths after splanchnic vein thrombosis occur in 5-30% of cases. Sequelae can be liver failure or bowel infarction after splanchnic vein thrombosis, renal insufficiency after renal vein thrombosis, ovarian infarction after ovarian vein thrombosis. Local cancer or infections are rare in Budd-Chiari syndrome, and common for other sites. Inherited thrombophilia is detected in 30-50% of patients. Myeloproliferative neoplasms are the main cause of splanchnic vein thrombosis: 20-50% of patients have an overt myeloproliferative neoplasm and/or carry the molecular marker JAK2 V617F. Renal vein thrombosis is closely related to nephrotic syndrome; finally, ovarian vein thrombosis can complicate puerperium. Heparin is used for acute treatment, sometimes in conjunction with systemic or local thrombolysis. Vitamin K-antagonists are recommended for 3-6 months, and long-term in patients with Budd-Chiari syndrome, unprovoked splanchnic vein thrombosis, or renal vein thrombosis with a permanent prothrombotic state such as nephrotic syndrome.

  4. Development of HIFU Therapy System for Lower Extremity Varicose Veins

    Science.gov (United States)

    Ota, Ryuhei; Suzuki, Jun; Yoshinaka, Kiyoshi; Deguchi, Juno; Takagi, Shu; Miyata, Tetsuro; Matsumoto, Yoichiro

    2009-04-01

    High-intensity focused ultrasound (HIFU) treatment utilizing microbubbles was investigated in the present study. It is known that microbubbles have the potential to enhance the heating effects of an ultrasound field. In this study, the heat accompanying microbubble oscillation was used to occlude varicose veins. Alteration of veins was observed after ultrasound irradiation. Veins were resected by stripping. In this study, two vein conditions were adopted during HIFU irradiation; non-compressed and compressed. Compressing the vein was expected to improve occlusion by rubbing the altered intima under compressed conditions. The frequency of the ultrasound was 1.7 MHz, the intensity at the focus was 2800 W/cm2, and the irradiation time was 20 s. In this study, the contrast agent Levovist® was chosen as a microbubble source, and the void fraction (ratio of total gas volume to liquid) in the vein was fixed at 10-5. Under non-compressed conditions, changes were observed only at the adventitia of the vein anterior wall. In contrast, under compressed conditions, changes were observed from the intima to the adventitia of both the anterior and posterior walls, and they were partly stuck together. In addition, more experiments with hematoxylin-eosin staining suggested that the changes in the vein were more substantial under the latter conditions. From these results, it was confirmed that the vein was occluded more easily with vein compression.

  5. Locative Inversion in Cantonese.

    Science.gov (United States)

    Mok, Sui-Sang

    This study investigates the phenomenon of "Locative Inversion" in Cantonese. The term "Locative Inversion" indicates that the locative phrase (LP) syntactic process in Cantonese and the appears at the sentence-initial position and its logical subject occurs postverbally. It is demonstrated that this Locative Inversion is a…

  6. Frictional melting processes and the generation of shock veins in terrestrial impact structures: Evidence from the Steen River impact structure, Alberta, Canada

    Science.gov (United States)

    Walton, Erin L.; Sharp, Thomas G.; Hu, Jinping

    2016-05-01

    Shock-produced melt within crystalline basement rocks of the Steen River impact structure (SRIS) are observed as thin (1-510 μm wide), interlocking networks of dark veins which cut across and displace host rock minerals. Solid-state phase transformations, such as ferro-pargasite to an almandine-andradite-majorite garnet and amorphization of quartz and feldspar, are observed in zones adjacent to comparatively wider (50-500 μm) sections of the shock veins. Shock pressure estimates based on the coupled substitution of Na+, Ti4+ and Si4+ for divalent cations, Al3+ and Cr3+ in garnet (14-19 GPa) and the pressure required for plagioclase (Ab62-83) amorphization at elevated temperature (14-20 GPa) are not appreciably different from those recorded by deformation effects observed in non-veined regions of the bulk rock (14-20 GPa). This spatial distribution is the result of an elevated temperature gradient experienced by host rock minerals in contact with larger volumes of impact-generated melt and large deviatoric stresses experienced by minerals along vein margins. Micrometer-size equant crystals of almandine-pyrope-majorite garnet define the shock vein matrix, consistent with rapid quench (100-200 ms) at 7.5-10 GPa. Crystallization of the vein occurred during a 0.1-0.15 s shock pressure pulse. Majoritic garnet, formed during shock compression by solid state transformation of pargasite along shock vein margins, is observed in TEM bright field images as nanometer-size gouge particles produced at strain rates in the supersonic field (106-108). These crystals are embedded in vesiculated glass, and this texture is interpreted as continued movement and heating along slip planes during pressure release. The deformation of high-pressure minerals formed during shock compression may be the first evidence of oscillatory slip in natural shock veins, which accounts for the production of friction melt via shear when little or no appreciable displacement is observed. Our observations

  7. Variations in the anatomical relationship between the common carotid artery and the internal jugular vein: An ultrasonographic study

    Directory of Open Access Journals (Sweden)

    Mauricio Umaña Perea

    2015-07-01

    Full Text Available Introduction:The internal jugular vein locates anterior or anterolateral to the common carotid artery in two-thirds of the subjects studied by ultrasound when the head is in a rotated position.Aim:To identify variables associated with the anterior location of the internal jugular vein.Methods:Ultrasound examinations were performed with the patients in the supine position, with the head rotated to the opposite side. The proximal third of the neck was visualized transversely with a 7.5-mHz transducer. The relationship between the vessels was described in accordance with the proportion of the artery overlapped by the vein. Univariate comparisons and a multivariate analysis of potential variables that may affect the anatomic relationships were performed.Results:Seventy-eight patients were included, 44 of whom were men. The patients' ages ranged from 17 to 90 years (median 64.0, interquartile range 41-73. The right and left sides were studied 75 and 73 times, respectively. The vein was located lateral to the artery in 24.3% (95%CI= 17.4-32.2 of the studies, anterolateral in 33.8% (95%CI= 26.2-41.4 and anterior in 41.9% (95%CI= 33.9-49.8. The multivariate analysis identified age group (OR= 3.7, 95% CI 2.1-6.4 and, less significantly, the left side (OR= 1.7, 95%CI= 0.8-3.5 and male gender (OR= 1.2, 95%CI= 0.6-2.7 as variables associated with the anterior position of the vein.Conclusión:The anterior position of the internal jugular vein relative to the common carotid artery increases gradually with age. Additionally, left-sided localization and male sex further increased the probability of an anterior position.

  8. Computed tomographic evaluation of the portal vein in the hepatomas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kee Hyung; Lee, Seung Chul; Bae, Man Gil; Seo, Heung Suk; Kim, Soon Yong; Lee, Min Ho; Kee, Choon Suhk; Park, Kyung Nam [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    1986-10-15

    Computed tomography and pornographic findings of 63 patients with hepatoma, undergone hepatic angiography and superior mesenteric pornography for evaluation of tumor and thrombosis of portal vein and determination of indication of transcatheter arterial embolization for palliative treatment of hepatoma from April, 85 to June, 86 in Hanyang university hospital, were reviewed. The results were as follows: 1. In 36 cases, portal vein thrombosis was detected during photography. Nineteen of 37 cases which revealed localized hepatoma in the right lobe of the liver showed portal vein thrombosis; 9 of 11 cases of the left lobe; 8 of 14 cases which were involved in entire liver revealed thrombosis. One case localized in the caudate lobe showed no evidence of invasion to portal vein. 2. Twenty-four of 34 cases with diffuse infiltrative hepatoma revealed portal vein thrombosis and the incidence of portal vein thrombosis in this type were higher than in the cases of the nodular type. 3. The portal vein thrombosis appeared as filling defects of low density in the lumen of the portal veins in CT and they did not reveal contrast enhancement. 4. CT revealed well the evidence of obstructions in the cases of portal vein thrombosis and the findings were well-corresponded to the findings of the superior mesenteric photography. 5. Five of the cases of the portal vein thrombosis were missed in the CT and the causes were considered as due to partial volume effect of enhanced portal vein with partial occlusion or arterioportal shunts. 6. Six of 13 cases with occlusion of main portal vein showed cavernous transformation and they were noted as multiple small enhanced vascularities around the porta hepatis in the CT. According to the results, we conclude that CT is a useful modality to detect the changes of the portal veins in the patients of the hepatoma.

  9. Structural determinants of tobacco vein mottling virus protease substrate specificity.

    Science.gov (United States)

    Sun, Ping; Austin, Brian P; Tözsér, József; Waugh, David S

    2010-11-01

    Tobacco vein mottling virus (TVMV) is a member of the Potyviridae, one of the largest families of plant viruses. The TVMV genome is translated into a single large polyprotein that is subsequently processed by three virally encoded proteases. Seven of the nine cleavage events are carried out by the NIa protease. Its homolog from the tobacco etch virus (TEV) is a widely used reagent for the removal of affinity tags from recombinant proteins. Although TVMV protease is a close relative of TEV protease, they exhibit distinct sequence specificities. We report here the crystal structure of a catalytically inactive mutant TVMV protease (K65A/K67A/C151A) in complex with a canonical peptide substrate (Ac-RETVRFQSD) at 1.7-Å resolution. As observed in several crystal structures of TEV protease, the C-terminus (∼20 residues) of TVMV protease is disordered. Unexpectedly, although deleting the disordered residues from TEV protease reduces its catalytic activity by ∼10-fold, an analogous truncation mutant of TVMV protease is significantly more active. Comparison of the structures of TEV and TVMV protease in complex with their respective canonical substrate peptides reveals that the S3 and S4 pockets are mainly responsible for the differing substrate specificities. The structure of TVMV protease suggests that it is less tolerant of variation at the P1' position than TEV protease. This conjecture was confirmed experimentally by determining kinetic parameters k(cat) and K(m) for a series of oligopeptide substrates. Also, as predicted by the cocrystal structure, we confirm that substitutions in the P6 position are more readily tolerated by TVMV than TEV protease.

  10. The care of patients with varicose veins and associated chronic venous diseases: clinical practice guidelines of the Society for Vascular Surgery and the American Venous Forum.

    Science.gov (United States)

    Gloviczki, Peter; Comerota, Anthony J; Dalsing, Michael C; Eklof, Bo G; Gillespie, David L; Gloviczki, Monika L; Lohr, Joann M; McLafferty, Robert B; Meissner, Mark H; Murad, M Hassan; Padberg, Frank T; Pappas, Peter J; Passman, Marc A; Raffetto, Joseph D; Vasquez, Michael A; Wakefield, Thomas W

    2011-05-01

    of the saphenous vein to the level of the knee (GRADE 1B). We recommend phlebectomy or sclerotherapy to treat varicose tributaries (GRADE 1B) and suggest foam sclerotherapy as an option for the treatment of the incompetent saphenous vein (GRADE 2C). We recommend against selective treatment of perforating vein incompetence in patients with simple varicose veins (CEAP class C(2); GRADE 1B), but we suggest treatment of pathologic perforating veins (outward flow duration ≥500 ms, vein diameter ≥3.5 mm) located underneath healed or active ulcers (CEAP class C(5)-C(6); GRADE 2B). We suggest treatment of pelvic congestion syndrome and pelvic varices with coil embolization, plugs, or transcatheter sclerotherapy, used alone or together (GRADE 2B).

  11. Portal vein and mesenteric vein gas: CT features; Aeroportie ety aeromesenterie: donnees TDM

    Energy Technology Data Exchange (ETDEWEB)

    Schmutz, G.; Fournier, L.; Le Pennec, V.; Provost, N.; Hue, S.; Phi, I.N. [Centre Hospitalier Universitaire, 14 - Caen (France)

    2001-04-01

    Portal vein and mesenteric vein gas are unusual conditions with a complex and nuclear pathogenesis. Mesenteric ischemia frequently causes such pathological conditions but a variety of other causes are known: inflammatory bowel disease, bowel distension, traumatic and iatrogenic injury, intra-abdominal sepsis, and idiopathic conditions. This pathologic entity is favored by intestinal wall alterations, bowel distension and sepsis. The prognosis is frequently fatal, especially when associated with extended bowel necrosis although in the majority of the cases, outcome is favorable without surgery. (author)

  12. Endovascular Laser Therapy for Varicose Veins

    Science.gov (United States)

    2010-01-01

    Executive Summary Objective The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and cost–effectiveness of endovascular laser therapy (ELT) for the treatment of primary symptomatic varicose veins (VV). Background The Ontario Health Technology Advisory Committee (OHTAC) met on November 27, 2009 to review the safety, effectiveness, durability and cost-effectiveness of ELT for the treatment of primary VV based on an evidence-based review by the Medical Advisory Secretariat (MAS). Clinical Condition VV are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins). Symptoms typically affect the lower extremities and include (but are not limited to): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad or worse as other chronic diseases such as

  13. Reproducibility of dorsal hand vein responses to phenylephrine and prostaglandin F2 alpha using the dorsal hand vein compliance method.

    Science.gov (United States)

    Schindler, C; Grossmann, M; Dobrev, D; Francke, K; Ravens, U; Kirch, W

    2003-03-01

    Assessment of drug-induced venodilation by the dorsal hand vein compliance method requires stable constriction of the vein. This study was designed to investigate intra- and intersubject reproducibility of the venous preconstriction technique in response to phenylephrine and prostaglandin F2 alpha and to determine the influence of basal vein size. Twelve healthy male nonsmokers participated in a prospective cross-over study. Inter- and intrasubject variability was tested in response to phenylephrine and PGF2 alpha on different study days in the same hand vein. The dose of the respective constrictor causing approximately 80% constriction of the vein (ED80) was determined and infused for another 100 minutes. Actual vein size was measured every 5 minutes. Coefficient of variation and regression analyses were performed to analyze influence of vessel size on ED80 of the respective constrictor. Adjusted constriction levels were stable and well reproducible in all subjects. The intersubject coefficient of variation of ED80 ranged from 0.9% to 6.7% for phenylephrine and from 0.9% to 6.9% for PGF2 alpha. Whereas responses to phenylephrine were independent of basal vein diameter, there was a positive correlation between ED80 of PGF2 alpha and basal vein size. Thus, the hand vein compliance method is a suitable method to study dilatory responses in phenylephrine- or PGF2 alpha-constricted veins with considerable interindividual but small intraindividual variability. However, in such studies, phenylephrine appears to be a more reliable tool than PGF2 alpha.

  14. Internal Jugular Vein Entrapment in a Multiple Sclerosis Patient

    Directory of Open Access Journals (Sweden)

    Marian Simka

    2012-01-01

    Full Text Available We describe a multiple sclerosis patient presenting with compression of the internal jugular vein caused by aberrant omohyoid muscle. Previously this patient underwent balloon angioplasty of the same internal jugular vein. Ten months after this endovascular procedure, Doppler sonography revealed totally collapsed middle part of the treated vein with no outflow detected. Still, the vein widened and the flow was restored when the patient’s mouth opened. Thus, the abnormality was likely to be caused by muscular compression. Surgical exploration confirmed that an atypical omohyoid muscle was squeezing the vein. Consequently, pathological muscle was transected. Sonographic control three weeks after surgical procedure revealed a decompressed vein with fully restored venous outflow. Although such a muscular compression can be successfully managed surgically, future research has to establish its clinical relevance.

  15. First records of syn-diagenetic non-tectonic folding in quaternary thermogene travertines caused by hydrothermal incremental veining

    Science.gov (United States)

    Billi, Andrea; Berardi, Gabriele; Gratier, Jean-Pierre; Rossetti, Federico; Vignaroli, Gianluca; Baykara, M. Oruç; Bernasconi, Stefano M.; Kele, Sándor; Soligo, Michele; De Filippis, Luigi; Shen, Chuan-Chou

    2017-03-01

    This study is the first documentation of syn-diagenetic non-tectonic contractional deformations observed in two Pleistocene thermogene travertine deposits from the late Miocene-Pleistocene Tuscan extensional-hydrothermal province (Italy). The deposits consist of primary porous beds hosting secondary bed-parallel carbonate veins. The porous beds are generally flat-lying, particularly in the upper section of the deposits, whereas the veined beds frequently form undulated structures. These structures are up to a few meters in wavelength, are mostly confined within the lower-middle section of the deposits, and are here mostly interpreted as folds. Field observations, U-Th geochronology, and stable isotope analyses are used to characterize the origin of veins and folds. Radiometrically-determined age inversions, structure overprinting relationships, downward growth of vein crystals, deformation of primary sedimentary structures, and downward increasing frequency of veins and folds show that the undulated travertine beds can be mainly interpreted as the product of syn-diagenetic hydrothermal rejuvenation causing non-tectonic veining and folding. The non-tectonic hypothesis is also supported by the absence of contractional deformation in the travertine-hosting sediments. The folds were generated by complex mechanisms including bending and buckling caused by laterally-confined volume expansion during syn-diagenetic circulation of mineralizing fluids and related incremental veining. Modeling some folds with the Biot-Ramberg's buckling equation shows a vein-to-host travertine viscosity ratio between 1.5 and 4, confirming the syn-diagenetic origin of folds. Veining and folding changed some original properties of travertines including rheology, fabric, porosity, and chronological sequence. The identification of these structures and related changes of rock properties (e.g., age rejuvenation) is relevant for the proper interpretation of thermogene travertines as recorders of

  16. Axion Crystals

    CERN Document Server

    Ozaki, Sho

    2016-01-01

    The low-energy effective theories for gapped insulators are classified by three parameters: permittivity $\\epsilon$, permeability $\\mu$, and theta angle $\\theta$. Crystals with periodic $\\epsilon$ are known as photonic crystals. We here study the band structure of photons in a new type of crystals with periodic $\\theta$ (modulo $2\\pi$) in space, which we call the axion crystals. We find that the axion crystals have a number of new properties that the usual photonic crystals do not possess, such as the helicity-dependent photonic band gaps and the nonrelativistic gapless dispersion relation at small momentum. We briefly discuss possible realizations of axion crystals in condensed matter systems as well as high-energy physics.

  17. Splenic vein leiomyosarcoma: case report and review of the literature.

    Science.gov (United States)

    Patrono, Damiano; Molinaro, Luca; Mazza, Elena; Romagnoli, Renato; Salizzoni, Mauro

    2014-09-28

    Primary venous leiomyosarcoma (LMS) is a rare disease, most commonly affecting the retroperitoneal veins and in particular the inferior vena cava. Five-year survival rate ranges between 33% and 68%. Complete surgical resection represents the only potentially curative treatment, occasionally achieving long-term survival. LMS of the splenic vein is extremely rare, with only three cases reported in the literature. We report a case of primary venous LMS arising from the splenic vein and we briefly review the relevant literature.

  18. Pediatric aneurysms and vein of Galen malformations

    Science.gov (United States)

    Rao, V. R. K.; Mathuriya, S. N.

    2011-01-01

    Pediatric aneurysms are different from adult aneurysms – they are more rare, are giant and in the posterior circulation more frequently than in adults and may be associated with congenital disorders. Infectious and traumatic aneursyms are also seen more frequently. Vein of Galen malformations are even rarer entities. They may be of choroidal or mural type. Based on the degree of AV shunting they may present with failure to thrive, with hydrocephalus or in severe cases with heart failure. The only possible treatment is by endovascular techniques – both transarterial and transvenous routes are employed. Rarely transtorcular approach is needed. These cases should be managed by an experienced neurointerventionist. PMID:22069420

  19. Electro-oculogram of Retinal Vein Occlusion

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    Twenty five cases, including 26 eyes with retinal vein occlusion (RVO) were examined by means of the electro-oculogram. The results showed that 23 of the 26 eyes suffering from RVO exhibited abnormalities of the electro-oculogram (EOG). The potential difference and Arden ratio in the RVO eyes were lower than those in the normal eyes (P<0.01). The more the visual acuity of ill eyes was decreased, the higher the abnormal rate of EOG in ill eyes was. 14 eyes had the visual acuity less than 0.1, whose EOGs ...

  20. Emerald mineralization and metasomatism of amphibolite, khaltaro granitic pegmatite - Hydrothermal vein system, Haramosh Mountains, Northern Pakistan

    Science.gov (United States)

    Laurs, B.M.; Dilles, J.H.; Snee, L.W.

    1996-01-01

    Emerald mineralization is found within 0.1- to 1-m-thick hydrothermal veins and granitic pegmatites cutting amphibolite within the Nanga Parbat - Haramosh massif, in northern Pakistan. The amphibolite forms a sill-like body within garnet-mica schist, and both are part of a regional layered gneiss unit of Proterozoic (?) age. The 40Ar/39Ar data for muscovite from a pegmatite yield a plateau age of 9.13 ?? 0.04 Ma. Muscovite from mica schist and hornblende from amphibolite yield disturbed spectra with interpreted ages of 9 to 10 Ma and more than 225 Ma, respectively, which indicate that peak Tertiary metamorphism reached 325 to 550??C prior to 10 Ma. Pegmatites were emplaced after peak metamorphism during this interval and are older than pegmatites farther south in the massif. At Khaltaro, simply zoned albite-rich miarolitic pegmatites and hydrothermal veins containing various proportions of quartz, albite, tourmaline, muscovite, and beryl are associated with a 1- to 3-m-thick heterogeneous leucogranite sill, that is locally albitized. The pegmatites likely crystallized at 650 to 600??C at pressures of less than 2 kbar. Crystals of emerald form within thin (0.20, 0.54-0.89 wt%), to pale blue beryl (<0.07, 0.10-0.63%), to colorless beryl (<0.07, 0.07-0.28%). The amphibolite is metasomatized in less than 20-cm-wide selvages that are symmetrically zoned around veins or pegmatites. A sporadic inner zone containing F-rich biotite, tourmaline, and fluorite, with local albite, muscovite, quartz, and rare beryl, gives way to an intermediate zone containing biotite and fluorite with local plagioclase and quartz, and to an outer zone of amphibolite containing sparse biotite and local quartz. The inner and intermediate zones experienced gains of K, H, F, B, Li, Rb, Cs, Be, Ta, Nb, As, Y and Sr, and losses of Si, Mg, Ca, Fe, Cr, V and Sc. The outer alteration zone has gained F, Li, Rb, Cs, and As. Oxygen isotope analyses of igneous and hydrothermal minerals indicate that a

  1. Zoning and sectoriality of the florencite and xenotime group minerals from quartz veins, the Subpolar Urals

    Science.gov (United States)

    Repina, S. A.

    2010-12-01

    A detailed study of the florencite and xenotime assemblage from quartz veins of Au-REE occurrences in the Subpolar Urals allowed the REE fractionation and distribution of REE mixtures in the crystal structure to be characterized. In minerals of selective composition, isomorphic mixtures of LREE and HREE are divided into lanthanum Lasg (La-Pr) and samarium Smsg (Nd-Eu) subgroups in florencite and gadolinium Gdsg (Gd-Dy) and ytterbium Ybsg (Ho-Lu) subgroups in xenotime. Concentrations of elements from these subgroups are inversely proportional to each other. Each florencite or xenotime crystal is characterized by several mineral varieties: xenotime-(Y) and Gd-bearing xenotime-(Y), florencite-(Sm), -(Nd), and -(Ce); they are selectively distributed by growth zones and pyramids of the crystal with formation of direct and inverse zoning. In both cases, cores of the crystals are enriched in HREE. The correlation between REEs, Y, and such trace elements as As, S, Ca, Sr, U, and Sc is established. REE deportment is considered in minerals formed as products of primary crystallization and hydrothermal redeposition. The REE fractionation is interpreted in terms of quantum mechanics.

  2. Image Quality Enhancement Using the Direction and Thickness of Vein Lines for Finger-Vein Recognition

    Directory of Open Access Journals (Sweden)

    Young Ho Park

    2012-10-01

    Experimental results from application of our proposed image enhancement method show that the equal error rate (EER of finger‐vein recognition decreases to approximately 0.4% in the case of a local binary pattern‐ based recognition and to approximately 0.3% in the case of a wavelet transform‐based recognition.

  3. An anomaly in persistent right umbilical vein of portal vein diagnosed by ultrasonography

    Institute of Scientific and Technical Information of China (English)

    Shigeo Nakanishi; Katsuya Shiraki; Kouji Yamamoto; Mutsumi Koyama; Takeshi Nakano

    2005-01-01

    AIM: To detect the anomaly in the persistent right umbilical vein (PRUV) of portal vein (PV) with deviation of the ligamentum tere and left-sided gallbladder.METHODS: A total of 5783 candidates for routine analysis were evaluated for hepatic vascular abnormalities by ultrasonography.RESULTS: Ten candidates (0.17%) had a portal vein anomaly with a rightward-deviated ligamentum tere.The blood-flow velocity in the PRUV of the portal vein (17.7±3.0 cm/s) of the 10 cases was similar to that of the right anterior portal trunk (17.6±4.1 cm/s). However,the vessel diameter of the PRUV (ψ12.4±4.4 mm) was larger than the right anterior portal trunk (ψ6.1±0.9 mm).Therefore, flow volume in the anomalous portion (0.97±0.30 L/min) was more than that in the right anterior portal trunk (0.18±0.05 L/min).CONCLUSION: The anomaly plays an important role in intra-hepatic PV flow.

  4. Evaluation of different systems for clinical quantification of varicose veins.

    Science.gov (United States)

    Cornu-Thénard, A; De Vincenzi, I; Maraval, M

    1991-04-01

    One hundred twenty-five lower limbs with varicose veins were studied clinically, essentially by palpation. Two specialists in venous pathology scored the severity of the varicose veins from 0 to 20. Comparison between the different clinical parameters and the scores of the specialists showed that two systems of clinical quantification gave good results and were easy to use. One system is the maximum diameter of the largest varicose vein; the other system is the sum of maximum diameters over 7 sections (3 for thigh, 3 for leg, 1 for foot). This latter system gives a more precise evaluation of the clinical severity of the varicose veins.

  5. Advantages of using volar vein repair in finger replantations.

    Science.gov (United States)

    Mersa, Berkan; Kabakas, Fatih; Pürisa, Hüsrev; Özçelik, Ismail Bülent; Yeşiloğlu, Nebil; Sezer, Ilker; Tunçer, Serdar

    2014-01-01

    Providing adequate venous outflow is essential in finger replantation surgeries. For a successful result, the quality and quantity of venous repairs should be adequate to drain arterial inflow. The digital dorsal venous plexus is a reliable source of material for venous repairs. Classically, volar digital veins have been used only when no other alternative was available. However, repairing volar veins to augment venous outflow has a number of technical advantages and gives a greater chance of survival. Increasing the repaired vein:artery ratio also increases the success of replantation. The volar skin, covering the volar vein, is less likely to be avulsed during injury and is also less likely to turn necrotic, than dorsal skin, after the replantation surgery. Primary repair of dorsal veins can be difficult due to tightness ensuing from arthrodesis of the underlying joint in flexion. In multiple finger replantations, repairing the volar veins after arterial repair and continuing to do so for each finger in the same way without changing the position of the hand and surgeon save time. In amputations with tissue loss, the size discrepancy is less for volar veins than for dorsal veins. We present the results of 366 finger replantations after volar vein repairs.

  6. [Portal perfusion with right gastroepiploic vein flow in liver transplant].

    Science.gov (United States)

    Mendoza-Sánchez, Federico; Javier-Haro, Francisco; Mendoza-Medina, Diego Federico; González-Ojeda, Alejandro; Cortés-Lares, José Antonio; Fuentes-Orozco, Clotilde

    Liver transplantation in patients with liver cirrhosis, portal vein thrombosis, and cavernous transformation of the portal vein, is a complex procedure with high possibility of liver graft dysfunction. It is performed in 2-19% of all liver transplants, and has a significantly high mortality rate in the post-operative period. Other procedures to maintain portal perfusion have been described, however there are no reports of liver graft perfusion using right gastroepiploic vein. A 20 year-old female diagnosed with cryptogenic cirrhosis, with a Child-Pugh score of 7 points (class "B"), and MELD score of 14 points, with thrombosis and cavernous transformation of the portal vein, severe portal hypertension, splenomegaly, a history of upper gastrointestinal bleeding due to oesophageal varices, and left renal agenesis. The preoperative evaluation for liver transplantation was completed, and the right gastroepiploic vein of 1-cm diameter was observed draining to the infrahepatic inferior vena cava and right suprarenal vein. An orthotopic liver transplantation was performed from a non-living donor (deceased on January 30, 2005) using the Piggy-Back technique. Portal vein perfusion was maintained using the right gastroepiploic vein, and the outcome was satisfactory. The patient was discharged 13 days after surgery. Liver transplantation was performed satisfactorily, obtaining an acceptable outcome. In this case, the portal perfusion had adequate blood flow through the right gastroepiploic vein. Copyright © 2015 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  7. Radiation Retinopathy Associated with Central Retinal Vein Occlusion

    Institute of Scientific and Technical Information of China (English)

    Yan; Liu; FengWen

    2007-01-01

    Purpose: To report a case of radiation retinopathy associated with central retinal vein occlusion.Methods: The clinical features and fundus fluorescein angiography of this case were analyzed.Results: The patient had been treated with radiotherapy for her nasopharyngeal carcinoma, and presented with sudden visual loss in the left eye. The funduscopic examination and fluorescein angiography showed the features of radiation retinopathy in both eyes, and central retinal vein occlusion in the left eye.Conclusions: Radiation retinopathy can be associated with central retinal vein occlusion in the same eye, and it seems that the endothelial cell loss caused by radiation retinopathy may lead to retinal vein occlusion.

  8. Extracorporeal Membrane Oxygenation Cannula Malposition in the Azygos Vein in a Neonate with Right-Sided Congenital Diaphragmatic Hernia

    Directory of Open Access Journals (Sweden)

    Seung Jun Choi

    2016-05-01

    Full Text Available Malposition of the extracorporeal membrane oxygenation (ECMO venous cannula in the azygos vein is not frequently reported. We hereby present such a case, which occurred in a neonate with right-sided congenital diaphragmatic hernia. Despite ECMO application, neither adequate flow nor sufficient oxygenation was achieved. On the cross-table lateral chest radiograph, the cannula tip was identified posterior to the heart silhouette, which implied malposition of the cannula in the azygos vein. After repositioning the cannula, the target flow and oxygenation were successfully achieved. When sufficient venous flow is not achieved, as in our case, clinicians should be alerted so they can identify the cannula tip location on lateral chest radiograph and confirm whether malposition in the azygos vein is the cause of the ineffective ECMO.

  9. Law Enforcement Locations

    Data.gov (United States)

    Kansas Data Access and Support Center — Law Enforcement Locations in Kansas Any location where sworn officers of a law enforcement agency are regularly based or stationed. Law enforcement agencies "are...

  10. NaAlSi3O8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Suizhou L6 chondrite contains a few very thin shock melt veins of 0.02-0.09 mm in width. In spite of small width of the veins, shock-induced high-pressure phases, such as coarse-grained NaAlSi3O8-hollandite, ringwoodite, majorite and fine-grained matrix majorite-pyropess have been discovered in these veins. NaAlSi3O8-hollandite, the high-pressure phase of plagioclase, in Suizhou shock veins occurs as a single phase mineral, no silicate glassy phase, such as albitic glass, was incorporated with it. The presence of above-mentioned high-pressure phases constrains the high pressure (up to 23-24 GPa) and high temperature (up to 1900-2000℃) regime in Suizhou shock veins, and indicates that the duration of high-pressure regime in the veins should be long enough (a few seconds) for phase transformation and crystallization of minerals under pressure. The discovery of the first natural single-phase crystalline NaAlSi3O8- hollan-dite in Suizhou meteorite is of important significance in un-derstanding the Earth's mantle geochemistry.

  11. Neonatal vitelline vein aneurysm with thrombosis: prompt treatment should be needed

    Science.gov (United States)

    Kim, Soo-Hong; Yu, Hyeong Won; Jo, Heui Seung

    2015-01-01

    Vitelline veins are a pair of embryonic structures. The veins develop the portal vein system. Serious problems occur if the vitelline vein does not regress and becomes an aneurysm. Thrombus formation in the vitelline vein aneurysm could lead to portal vein thrombosis and portal hypertension unless promptly and correctly treated. Though vitelline vein aneurysm is an extremely rare anomaly, it rapidly progresses to portal vein thrombosis that requires prompt diagnosis and treatment. We reported a case of neonatal vitelline vein aneurysm and thrombosis that was cured by prompt operation. PMID:26665130

  12. Multiple abdominal veins thrombosis secondary to protein s deficiency - a case report.

    Science.gov (United States)

    Kodali, Venkata Umakant; Borra, Seshulakshmi; Mandarapu, Surendra Babu; Sanda, Mallikarjuna Rao; Bolla, Srinivasa Rao

    2014-06-01

    Abdominal venous thrombosis may present either as Budd-Chiari syndrome (BCS) caused by hepatic vein or proximal inferior vena cava (IVC) obstruction or as an extra hepatic portal obstruction (EHPVO) caused by Portal vein thrombosis or mesenteric vein thrombosis, but a mixed involvement is uncommon. Multiple abdominal venous obstructions presenting with thrombosis of hepatic vein, IVC, portal vein and renal vein are very rarely seen . We are reporting a rare case with thrombosis of IVC, hepatic vein, portal vein and renal vein, with protein S and protein C deficiencies, which was managed by giving anticoagulant therapy.

  13. Is localised dehydration and vein generation the tremor-generating mechanism in subduction zones?

    Science.gov (United States)

    Fagereng, Ake; Meneghini, Francesca; Diener, Johann; Harris, Chris

    2017-04-01

    The phenomena of tectonic, non-volcanic, tremor was first discovered at the down-dip end of the seismogenic zone in Japan early this millennium. Now this low amplitude, low frequency, noise-like seismic signal has been observed at and/or below the deep limit of interseismic coupling along most well-instrumented subduction thrust interfaces. Data and models from these examples suggest a link between tremor and areas of elevated fluid pressure, or at least fluid presence. Tremor locations appear to also correlate with margin-specific locations of metamorphic fluid release, determined by composition and thermal structure. We therefore hypothesise that: (i) tremor on the deep subduction thrust interface is related to localised fluid release; and (ii) accretionary complex rocks exhumed from appropriate pressure - temperature conditions should include a record of this process, and allow a test for the hypothesis. Hydrothermal veins are a record of mineral precipitation at non-equilibrium conditions, commonly caused by fracture, fluid influx, and precipitation of dissolved minerals from this fluid. Quartz veins are ubiquitous in several accretionary complexes, including the Chrystalls Beach Complex, New Zealand, and the Kuiseb Schist of the Namibian Damara Belt. In both locations, representing temperatures of deformation of < 300 and < 600 °C respectively, there are networks of foliation-parallel and oblique veins, which developed incrementally and record a combination of shear and dilation. Required to have formed at differential stresses less than four times the tensile strength, and at fluid pressures exceeding the least compressive stress, these veins are consistent with tremorgenic conditions of low effective stress and mixed-mode deformation kinematically in agreement with shear on the plate interface. We have analysed the oxygen isotope composition of syntectonic quartz veins in both Chrystalls Beach Complex and Kuiseb Schist accretionary complexes, to unravel the

  14. Can deep vein thrombosis be predicted after varicose vein operation in women in rural areas?

    Directory of Open Access Journals (Sweden)

    Marcin Warot

    2014-09-01

    Full Text Available [b]Introduction[/b]. Chronic venous disease is a group of symptoms caused by functional and structural defects of the venous vessels. One of the most common aspects of this disease is the occurrence of varicose veins. There are many ways of prevention and treatment of varicose veins, but in Poland the leading one is still surgery. As in every medical procedure there is the possibility of some complications. One of them is deep vein thrombosis (DVT. The diagnosis of DVT can be difficult, especially when access to a specialist is limited, such as in case of rural patients. [b]The aim of the study.[/b] The aim of the study was estimation of the influence of LMWH primary prophylaxis on the formation of postoperative DVT, as well as sensitivity and specificity of clinical examination and D-dimer value in diagnosis of postoperative DVT in women. [b]Materials and methods[/b]. The study was conducted in a group of 93 women operated on in the Department of General, Vascular Surgery and Angiology at the Karol Marcinkowski University of Medical Sciences in Poznań, Poland. The patients had undergone a varicose vein operation and were randomly divided into two groups: A – 48 women receiving LMWH during two days of the perioperative period, B – 45 women receiving LMWH during seven days of the perioperative period. [b]Results[/b]. There was no significant difference in the postoperative DVT complications in both groups. The value of D-dimer > 0.987 mcg/ml and swelling > 1.5 cm of shin (in comparison to the preoperative period plays a significant role in diagnosis of DVT. [b]Conclusions[/b]. The extended primary prophylaxis with LMWH does not affect the amount or quality of thrombotic complications after varicose vein operation. If the DVT occurs, the evaluation of the D – dimer and careful clinical examination can be a useful method for its diagnosis.

  15. Onderzoek location based marketing: Mobile = location = effect

    NARCIS (Netherlands)

    Gisbergen, M.S. van; Huhn, A.E.; Khan, V.J.; Ketelaar, P.E.

    2011-01-01

    Onderzoekers van de NHTV (Internationaa Hoger Onderwijs Breda, Radboud Universiteit, DVJ Insights en Popai Benelux lieten consumenten in een virtuele supermarkt advertenties via de smartphone ontvangen wanneer men langs het geadverteerde product liep. De uitkomsten laten zien dat 'location based adv

  16. Onderzoek location based marketing: Mobile = location = effect

    OpenAIRE

    Gisbergen, M.S. van; Huhn, A.E.; Khan, V.J.; Ketelaar, P.E.

    2011-01-01

    Onderzoekers van de NHTV (Internationaa Hoger Onderwijs Breda, Radboud Universiteit, DVJ Insights en Popai Benelux lieten consumenten in een virtuele supermarkt advertenties via de smartphone ontvangen wanneer men langs het geadverteerde product liep. De uitkomsten laten zien dat 'location based advertising' effectief is.

  17. Locatives in Kpelle.

    Science.gov (United States)

    Kuha, Mai

    This paper examines the differences between locative expressions in Kpelle and English, based on the dialect of one native speaker of Kpelle. It discusses the crucial role of the reference object in defining the meaning of locatives in Kpelle, in contrast to English, where the characteristics of the object to be located are less important. An…

  18. Arterialization and anomalous vein wall remodeling in varicose veins is associated with upregulated FoxC2-Dll4 pathway.

    Science.gov (United States)

    Surendran, Sumi; S Ramegowda, Kalpana; Suresh, Aarcha; Binil Raj, S S; Lakkappa, Ravi Kumar B; Kamalapurkar, Giridhar; Radhakrishnan, N; C Kartha, Chandrasekharan

    2016-04-01

    Varicose veins of lower extremities are a heritable common disorder. Mechanisms underlying its pathogenesis are still vague. Structural failures such as valve weakness and wall dilatation in saphenous vein result in venous retrograde flow in lower extremities of body. Reflux of blood leads to distal high venous pressure resulting in distended veins. In an earlier study, we observed a positive association between c.-512C>T FoxC2 gene polymorphism and upregulated FoxC2 expression in varicose vein specimens. FoxC2 overexpression in vitro in venous endothelial cells resulted in the elevated mRNA expression of arterial endothelial markers such as Delta-like ligand 4 (Dll4) and Hairy/enhancer-of-split related with YRPW motif protein 2 (Hey2). We hypothesized that an altered FoxC2-Dll4 signaling underlies saphenous vein wall remodeling in patients with varicose veins. Saphenous veins specimens were collected from 22 patients with varicose veins and 20 control subjects who underwent coronary artery bypass grafting. Tissues were processed for paraffin embedding and sections were immunostained for Dll4, Hey2, EphrinB2, α-SMA, Vimentin, and CD31 antigens and examined under microscope. These observations were confirmed by quantitative real-time PCR and western blot analysis. An examination of varicose vein tissue specimens by immunohistochemistry indicated an elevated expression of Notch pathway components, such as Dll4, Hey2, and EphrinB2, and smooth muscle markers, which was further confirmed by gene and protein expression analyses. We conclude that the molecular alterations in Dll4-Hey2 signaling are associated with smooth muscle cell hypertrophy and hyperplasia in varicose veins. Our observations substantiate a significant role for altered FoxC2-Dll4 signaling in structural alterations of saphenous veins in patients with varicose veins.

  19. Lasing from fluorescent protein crystals.

    Science.gov (United States)

    Oh, Heon Jeong; Gather, Malte C; Song, Ji-Joon; Yun, Seok Hyun

    2014-12-15

    We investigated fluorescent protein crystals for potential photonic applications, for the first time to our knowledge. Rod-shaped crystals of enhanced green fluorescent protein (EGFP) were synthesized, with diameters of 0.5-2 μm and lengths of 100-200 μm. The crystals exhibit minimal light scattering due to their ordered structure and generate substantially higher fluorescence intensity than EGFP or dye molecules in solutions. The magnitude of concentration quenching in EGFP crystals was measured to be about 7-10 dB. Upon optical pumping at 485 nm, individual EGFP crystals located between dichroic mirrors generated laser emission with a single-mode spectral line at 513 nm. Our results demonstrate the potential of protein crystals as novel optical elements for self-assembled, micro- or nano-lasers and amplifiers in aqueous environment.

  20. Biomolecular mechanisms in varicose veins development.

    Science.gov (United States)

    Segiet, Oliwia Anna; Brzozowa-Zasada, Marlena; Piecuch, Adam; Dudek, Damian; Reichman-Warmusz, Edyta; Wojnicz, Romuald

    2015-02-01

    Varicose veins (VVs) can be described as tortuous and dilated palpable veins, which are more than 3 mm in diameter. They are one of the clinical presentations of chronic venous disorders, which are a significant cause of morbidity. The prevalence of VVs has been estimated at 25-33% in women and 10-20% in men and is still increasing at an alarming rate. Family history, older age, female, pregnancy, obesity, standing occupations, and a history of deep venous thrombosis are the predominant risk factors. A great amount of factors are implicated in the pathogenesis of VVs, including changes in hydrostatic pressure, valvular incompetence, deep venous obstruction, ineffective function of calf muscle pump, biochemical and structural alterations of the vessel wall, extracellular matrix abnormalities, impaired balance between growth factors or cytokines, genetic alterations, and several other mechanisms. Nevertheless, the issue of pathogenesis in VVs is still not completely known, even if a great progress has been made in understanding their molecular basis. This kind of studies appears promising and should be encouraged, and perhaps the new insight in this matter may result in targeted therapy or possibly prevention.

  1. The valves and tributary veins of the saphenofemoral junction: ultrasound findings in normal limbs

    Directory of Open Access Journals (Sweden)

    Riordon Dickson

    2013-08-01

    Full Text Available In the past the saphenofemoral junction (SFJ for the surgeon was regarded as a simple conduit to be obliterated. With modern ultrasound we can distinguish the components of this complex structure and examine their haemodynamic function and suggest more haemodynamically-focused interventions. Despite this, there are no ultrasound studies describing the components of the normal SFJ and their haemodynamic significance. Patients attending our vascular laboratory with suspected deep vein thrombosis were screened and the SFJ in 75 limbs with no physiological or haemodynamic abnormalities were examined. The terminal (TV and preterminal (PTV valve morphology and the distance from the SFJ were assessed. The number of tributaries and their position relative to these valves was also examined. TV and PTVs were identified on ultrasound in all 75 limbs. TVs were found at a mean distance of 0.4 cm (range 0–1.2 cm from the SFJ. Nearly a third of all limbs had at least one tributary vein identified superior to the TV. The greater the distance to the TV, the greater the number of tributary veins one should expect to find superior to the TV. PTV location was more variable. PTVs were identified at a mean distance of 3.1 cm (range 0.4–8.7 cm, giving rise to a large number of configurations of tributary veins in the intervalve space. This study characterizes the ultrasound appearances of the normal SFJ and compares these with reported anatomical studies. Valves can be consistently identified whereas the number and location of the tributaries are very variable. This should inform planning of haemodynamically-focused treatment at the SFJ.

  2. Noise Source Location Optimization

    Directory of Open Access Journals (Sweden)

    Ed O’Keefe

    1994-01-01

    Full Text Available This article describes a method to determine locations of noise sources that minimize modal coupling in complex acoustic volumes. Using the acoustic source scattering capabilities of the boundary element method, predictions are made of mode shape and pressure levels due to various source locations. Combining knowledge of the pressure field with a multivariable function minimization technique, the source location generating minimum pressure levels can be determined. The analysis also allows for an objective comparison of “best/worst” locations. The technique was implemented on a personal computer for the U.S. Space Station, predicting 5–10 dB noise reduction using optimum source locations.

  3. Smartphones as locative media

    CERN Document Server

    Frith, Jordan

    2015-01-01

    Smartphone adoption has surpassed 50% of the population in more than 15 countries, and there are now more than one million mobile applications people can download to their phones. Many of these applications take advantage of smartphones as locative media, which is what allows smartphones to be located in physical space. Applications that take advantage of people's location are called location-based services, and they are the focus of this book. Smartphones as locative media raise important questions about how we understand the complicated relationship between the Internet and physical space

  4. RNA Crystallization

    Science.gov (United States)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  5. Looking at Dauphiné twins in vein quartz as a potential paleostress indicator

    Science.gov (United States)

    Sintubin, Manuel; Wenk, Hans-Rudolf

    2013-04-01

    Paleostress studies commonly call upon (1) a fault slip data inversion technique, (2) a calcite twin stress inversion technique, (3) recrystallized grain size piezometry for quartz, or (4) direct measurements of residual lattice strain. Recent advances in orientation imaging microscopy (OIM) using electron backscatter diffraction (EBSD) on a scanning electron microscope (SEM) have revealed that Dauphiné twinning is very common in quartz in naturally deformed quartz-bearing rocks in a wide range of tectonometamorphic conditions. It has long been known that mechanical Dauphiné twinning in quartz can be stress-induced. Based on the results of an extensive EBSD-OIM analysis on vein quartz, taken from well-studied early to late-orogenic veins in the High-Ardenne slate belt (Germany, Belgium), we explore the potential use of mechanical Dauphiné twins as a paleostress indicator, possibly completing our toolbox for reconstructing paleostresses in the Earth's crust. The vein quartz studied precipitated in low-grade tectonometamorphic conditions (~200-400°C), typical for the brittle-plastic transition zone at the base of the seismogenic crust (~7-15km). Quartz has only been weakly affected by low to moderate temperature (200 to 400°C) crystal-plastic deformation. The samples show grains with a high concentration of Dauphiné twin boundaries and others free of twin boundaries, thus being untwinned or completely twinned. This pattern depends on the crystallographic orientation. Twin boundaries are arrested by grain or subgrain boundaries, suggesting that Dauphiné twinning occurred on a pre-existing fabric that resulted from crystal-plastic deformation. An analysis of the orientation distribution of the rhombs in the twinned variant domains of individual quartz (sub-)grains reveals a particular preferred orientation of the poles to rhombs. We will discuss the possible significance of these observations with respect to paleostresses that may have caused the mechanical

  6. Protein Crystallization

    Science.gov (United States)

    Chernov, Alexander A.

    2005-01-01

    Nucleation, growth and perfection of protein crystals will be overviewed along with crystal mechanical properties. The knowledge is based on experiments using optical and force crystals behave similar to inorganic crystals, though with a difference in orders of magnitude in growing parameters. For example, the low incorporation rate of large biomolecules requires up to 100 times larger supersaturation to grow protein, rather than inorganic crystals. Nucleation is often poorly reproducible, partly because of turbulence accompanying the mixing of precipitant with protein solution. Light scattering reveals fluctuations of molecular cluster size, its growth, surface energies and increased clustering as protein ages. Growth most often occurs layer-by-layer resulting in faceted crystals. New molecular layer on crystal face is terminated by a step where molecular incorporation occurs. Quantitative data on the incorporation rate will be discussed. Rounded crystals with molecularly disordered interfaces will be explained. Defects in crystals compromise the x-ray diffraction resolution crucially needed to find the 3D atomic structure of biomolecules. The defects are immobile so that birth defects stay forever. All lattice defects known for inorganics are revealed in protein crystals. Contribution of molecular conformations to lattice disorder is important, but not studied. This contribution may be enhanced by stress field from other defects. Homologous impurities (e.g., dimers, acetylated molecules) are trapped more willingly by a growing crystal than foreign protein impurities. The trapped impurities induce internal stress eliminated in crystals exceeding a critical size (part of mni for ferritin, lysozyme). Lesser impurities are trapped from stagnant, as compared to the flowing, solution. Freezing may induce much more defects unless quickly amorphysizing intracrystalline water.

  7. Computational crystallization.

    Science.gov (United States)

    Altan, Irem; Charbonneau, Patrick; Snell, Edward H

    2016-07-15

    Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed.

  8. Vein wall remodeling after deep vein thrombosis: differential effects of low molecular weight heparin and doxycycline.

    Science.gov (United States)

    Sood, Vikram; Luke, Cathy; Miller, Erin; Mitsuya, Mayo; Upchurch, Gilbert R; Wakefield, Thomas W; Myers, Dan D; Henke, Peter K

    2010-02-01

    Venous thrombus resolution sets up an early intense inflammatory reaction, from which vein wall damage results. Tissue response to injury includes matrix metalloproteinase (MMP) activation and extracellular matrix protein turnover. This study sought to determine the effect of exogenous MMP inhibition and its potential attenuation of early vein wall injury. Rats received treatment beginning 24 hr after a stasis venous thrombosis by near occlusive ligation and until harvest at day 7. Three groups were evaluated: (1) vehicle saline controls (NaCl), (2) low molecular weight heparin (LMWH; Lovenox, 3 mg/kg daily SQ), and (3) doxycycline (DOXY, 30 mg/kg daily PO). Thrombus size (mg/mm), levels of tumor necrosis factor alpha (TNF alpha) and D-dimer by colorimetric assay, and monocytes counts by immunohistochemistry were assessed. Vein wall assessment included stiffness by tensiometry, interleukin 1beta (IL-1 beta protein levels by enzyme-linked immunosorbent assay, MMP2 and -9 by zymography, and histological analysis of intimal thickness (IT). Comparisons were by t-test to control. p DOXY-treated groups (NaCl = 1.0 +/- 0.8, LWMH = 9 +/- 3, DOXY = 27 +/- 5 pg/mg protein, n = 6-8, p DOXY group (NaCl = 3.0 +/- 2.5, DOXY = 23 +/- 4.2 pg/mg protein, n = 5, p DOXY, compared to controls (NaCl = 0.33 +/- 0.05, LMWH = 0.17 +/- 0.03, DOXY = 0.43 +/- 0.09 N/mm, n = 5-7, p DOXY group at 7 days (NaCl = 26 +/- 3, LMWH = 38 +/- 17, DOXY = 6 +/- 3 pg/mg protein, n = 4-6, p DOXY = 0.8 +/- 0.20, n = 4-6, p DOXY groups (NaCl = 85 +/- 24, LMWH = 23 +/- 7( *), DOXY = 13 +/- 5 U/mg protein, n = 6-8, p DOXY did not alter the size of deep vein thrombosis, mildly altered thrombus composition, and differentially affected vein wall injury, despite similar reductions in early MMP9 activity. Whether exogenous MMP inhibition affects long-term vein wall fibrosis will require further study. Copyright 2010 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

  9. Synchrotron radiation X-ray diffraction in situ study of fine-grained minerals in shock veins of Suizhou meteorite

    Institute of Scientific and Technical Information of China (English)

    XIE Xiande; SHU Jinfu; CHEN Ming

    2005-01-01

    The synchrotron radiation X-ray diffraction technique developed for in situ study at high pressure and temperature has also been used to investigate microscopic mineral inclusions in ultrahigh-pressure metamorphic rocks and deep-mantle samples. Present study added two more examples of successful utilization of synchrotron radiation X-ray diffraction technique for in situ investigations of fine-grained (0.5―30μm in size) minerals in very thin shock melt veins of the Suizhou meteorite: ( i ) X-ray diffraction measurement of extremely small-sized vein matrix minerals, and (ii) identification of the micron-sized new mineral tuite embedded in the vein matrix. It has been revealed that the fine-grained vein matrix consists of well crystallized garnet, kamacite and troilite, and the powder diffraction pattern consisting of 17 lines with d-values, intensities ( I ), relative intensities (I/Io) and Miller indices, as well as the cell parameters for the new mineral tuite has also been successfully obtained. The result of present investigations has enriched the content of dynamic high-pressure mineralogy and that of Earth's mantle geochemistry.

  10. A study of images of Projective Angles of pulmonary veins

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jue [Beijing Anzhen Hospital, Beijing (China); Zhaoqi, Zhang [Beijing Anzhen Hospital, Beijing (China)], E-mail: zhaoqi5000@vip.sohu.com; Yu Wei; Miao Cuilian; Yan Zixu; Zhao Yike [Beijing Anzhen Hospital, Beijing (China)

    2009-09-15

    Aims: In images of magnetic resonance and computed tomography (CT) there are visible angles between pulmonary veins and the coronary, transversal or sagittal section of body. In this study these angles are measured and defined as Projective Angles of pulmonary veins. Several possible influential factors and characters of distribution are studied and analyzed for a better understanding of this imaging anatomic character of pulmonary veins. And it could be the anatomic base of adjusting correctly the angle of the central X-ray of the angiography of pulmonary veins undergoing the catheter ablation of atrial fibrillation (AF). Method: Images of contrast enhanced magnetic resonance angiography (CEMRA) and contrast enhanced computer tomography (CECT) of the left atrium and pulmonary veins of 137 health objects and patients with atrial fibrillation (AF) are processed with the technique of post-processing, and Projective Angles to the coronary and transversal sections are measured and analyzed statistically. Result: Project Angles of pulmonary veins are one of real and steady imaging anatomic characteristics of pulmonary veins. The statistical distribution of variables is relatively concentrated, with a fairly good representation of average value. It is possible to improve the angle of the central X-ray according to the average value in the selective angiography of pulmonary veins undergoing the catheter ablation of AF.

  11. AUTOLOGOUS VEIN SUPPORTED WITH A BIODEGRADABLE PROSTHESIS FOR ARTERIAL GRAFTING

    NARCIS (Netherlands)

    ZWEEP, HP; SATOH, S; VANDERLEI, B; HINRICHS, WLJ; DIJK, F; FEIJEN, J; WILDEVUUR, CRH

    1993-01-01

    To evaluate the potential of a supporting, compliant, biodegradable prosthesis to function as a temporary protective scaffold for autologous vein grafts in the arterial circulation, we implanted vein grafts into the carotid arteries of rabbits, either with (composite grafts) or without (control graf

  12. Quantification of deep medullary veins at 7 T brain MRI

    NARCIS (Netherlands)

    Kuijf, Hugo J.; Bouvy, Willem H.; Zwanenburg, Jaco J M; Schultz, Tom B Razoux; Viergever, Max A.; Vincken, Koen L.; Biessels, Geert Jan

    2016-01-01

    Objectives: Deep medullary veins support the venous drainage of the brain and may display abnormalities in the context of different cerebrovascular diseases. We present and evaluate a method to automatically detect and quantify deep medullary veins at 7 T. Methods: Five participants were scanned

  13. Quantification of deep medullary veins at 7 T brain MRI

    NARCIS (Netherlands)

    Kuijf, Hugo J.; Bouvy, Willem H.; Zwanenburg, Jaco J M; Schultz, Tom B Razoux; Viergever, Max A.; Vincken, Koen L.; Biessels, Geert Jan

    2016-01-01

    Objectives: Deep medullary veins support the venous drainage of the brain and may display abnormalities in the context of different cerebrovascular diseases. We present and evaluate a method to automatically detect and quantify deep medullary veins at 7 T. Methods: Five participants were scanned twi

  14. Finger-vein image separation algorithms and realization with MATLAB

    Science.gov (United States)

    Gao, Xiaoyan; Ma, Junshan; Wu, Jiajie

    2010-10-01

    According to the characteristics of the finger-vein image, we adopted a series of methods to enhance the contrast of the image in order to separate the finger-vein areas from the background areas, and made prepare for the subsequent research such as feature extraction and recognition processing . The method consists of three steps: denoising, contrast enhancement and image binarization. In denoising, considering the relationship between gray levels in the adjacent areas of the finger-vein image, we adopted the Gradient Inverse Weighted Smoothing method. In contrast enhancement, we improved the conventional High Frequency Stress Filtering method and adopted a method which combined the traditional High Frequency Stress Filtering algorithm together with the Histogram Equalization. With this method, the contrast of the finger-vein area and the background area has been enhanced significantly. During the binarization process, after taking the differences of the gray levels between the different areas of the finger-vein image into consideration, we proposed a method which combined the binarization by dividing the image into several segments and the Morphological Image Processing means. Our experiment results show that after a series of processing mentioned above by using MATLAB, the finger-vein areas can be separated from the background areas obviously. We can get a vivid figure of the finger-vein which provided some references for the following research such as finger-vein image feature extraction, matching and identification.

  15. A Tight Spot After Pulmonary Vein Catheter Ablation

    NARCIS (Netherlands)

    Amir, Rabia; Yeh, Lu; Montealegre-Gallegos, Mario; Saraf, Rabya; Matyal, Robina; Mahmood, Feroze

    2016-01-01

    A 52-YEAR-OLD woman with a history of embolic stroke due to paroxysmal atrial fibrillation was referred to the authors’ institution for epicardial surgical pulmonary vein isolation with left atrial appendage resection. The patient had 2 previous failed pulmonary vein catheter ablations. Dense

  16. Pressure-diameter relationship in the human greater saphenous vein

    NARCIS (Netherlands)

    Stooker, W; Gok, M; Sipkema, P; Niessen, HWM; Baidoshvili, A; Westerhof, N; Jansen, EK; Wildevuur, CRH; Eijsman, L

    2003-01-01

    Background. Compliance of artificial and autologous vascular grafts is related to future patency. We investigated whether differences in compliance exist between saphenous vein grafts derived from the upper or lower leg, which might indicate upper or lower leg saphenous vein preference in coronary a

  17. A Tight Spot After Pulmonary Vein Catheter Ablation

    NARCIS (Netherlands)

    Amir, Rabia; Yeh, Lu; Montealegre-Gallegos, Mario; Saraf, Rabya; Matyal, Robina; Mahmood, Feroze

    2016-01-01

    A 52-YEAR-OLD woman with a history of embolic stroke due to paroxysmal atrial fibrillation was referred to the authors’ institution for epicardial surgical pulmonary vein isolation with left atrial appendage resection. The patient had 2 previous failed pulmonary vein catheter ablations. Dense fibrou

  18. [Treatment of pulmonary vein stenosis secondary to radiofrequency ablation].

    Science.gov (United States)

    Ferrero Guadagnoli, Adolfo; Contreras, Alejandro E; Leonardi, Carlos R; Ballarino, Miguel A; Atea, Leonardo; Peirone, Alejandro R

    2014-01-01

    Isolation of the pulmonary veins by applying radiofrequency is an effective treatment for atrial fibrillation. One of the potential complications with higher clinical compromise utilizing this invasive technique is the occurrence of stenosis of one or more pulmonary veins. This complication can be treated by angioplasty with or without stent implantation, with an adequate clinical improvement, but with a high rate of restenosis.

  19. Dorzolamide increases retinal oxygen tension after branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Noergaard, Michael Hove; Bach-Holm, Daniella; Scherfig, Erik;

    2008-01-01

    To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs.......To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs....

  20. Endovascular exclusion of a large external iliac vein aneurysm.

    Science.gov (United States)

    Todorov, Mina; Hernandez, Diego

    2013-07-01

    Iliac vein aneurysms are uncommon, and there is no consensus on optimal treatment. We present a case of venous exclusion using an endovascular approach. To our knowledge, this is the first reported case of a large external iliac vein aneurysm treated endovascularly. We have demonstrated the feasibility of this approach with satisfactory 1-year follow-up.

  1. The anatomy of the iliolumbar vein. A cadaver study.

    Science.gov (United States)

    Jasani, Vinay; Jaffray, David

    2002-09-01

    We carried out a cadaver study of 16 iliolumbar veins in order to define the surgical anatomy. Two variants were found; a single vein at a mean distance of 3.74 cm from the inferior vena cava (11 of 16) and two separate draining veins at a mean distance from the vena cava of 2.98 cm for the proximal and 6.24 cm for the distal stem (5 of 16). Consistently, the proximal vein tore on attempted medial retraction of the great vessels. The mean length of the vein was 1.6 cm and its mean width 1.07 cm. Three stems were shorter than 0.5 cm. Two or more tributaries usually drained the iliacus and psoas muscles, and the fifth lumbar vertebral body. The obturator nerve crossed all veins superficially at a mean of 2.76 cm lateral to the mouth. In four of these, this distance was less than 1.5 cm. Usually, the lumbosacral trunk crossed deep, at a mean distance of 2.5 cm lateral to the mouth, but in three veins, this distance was 1 cm or less. Our findings emphasise the need for proper dissection of the iliolumbar vein before ligature during exposure of the anterior lumbar spine.

  2. Portal vein embolization induces compensatory hypertrophy of remnant liver

    Institute of Scientific and Technical Information of China (English)

    Jing-Yao Huang; Wei-Zhu Yang; Jian-Jun Li; Na Jiang; Qu-Bin Zheng

    2006-01-01

    AIM: To evaluate the effectiveness and safety of different portal vein branch embolization agents in inducing compensatory hypertrophy of the remnant liver and to offer a theoretic basis for clinical portal vein branch embolization.METHODS: Forty-one adult dogs were included in the experiment and divided into four groups. Five dogs served as a control group, 12 as a gelfoam group, 12as a coil-gelfoam group and 12 as an absolute ethanol group. Left portal vein embolization was performed in each group. The results from the embolization in each group using different embolic agents were compared.The safety of portal vein embolization (PVE) was evaluated by liver function test, computed tomography (CT) and digital subtraction angiography (DSA) of liver and portal veins. Statistical test of variance was performed to analyze the results.RESULTS: Gelfoam used for PVE was inefficient in recanalization of portal vein branch 4 wk after the procedure. The liver volume in groups of coil-gelfoam and absolute ethanol increased 25.1% and 33.18%,respectively. There was no evidence of recanalization of embolized portal vein, hepatic dysfunction, and portal hypertension in coil-gelfoam group and absolute ethanol group.CONCOUSION: Portal vein branch embolization using absolute ethanol and coil-gelfoam could induce atrophy of the embolized lobes and compensatory hypertrophy of the remnant liver. Gelfoam is an inefficient agent.

  3. Endovascular management for significant iatrogenic portal vein bleeding.

    Science.gov (United States)

    Kim, Jong Woo; Shin, Ji Hoon; Park, Jonathan K; Yoon, Hyun-Ki; Ko, Gi-Young; Gwon, Dong Il; Kim, Jin Hyoung; Sung, Kyu-Bo

    2017-01-01

    Background Despite conservative treatment, hemorrhage from an intrahepatic branch of the portal vein can cause hemodynamic instability requiring urgent intervention. Purpose To retrospectively report the outcomes of hemodynamically significant portal vein bleeding after endovascular management. Material and Methods During a period of 15 years, four patients (2 men, 2 women; median age, 70.5 years) underwent angiography and embolization for iatrogenic portal vein bleeding. Causes of hemorrhage, angiographic findings, endovascular treatment, and complications were reported. Results Portal vein bleeding occurred after percutaneous liver biopsy (n = 2), percutaneous radiofrequency ablation (n = 1), and percutaneous cholecystostomy (n = 1). The median time interval between angiography and percutaneous procedure was 5 h (range, 4-240 h). Common hepatic angiograms including indirect mesenteric portograms showed active portal vein bleeding into the peritoneal cavity with (n = 1) or without (n = 2) an arterioportal (AP) fistula, and portal vein pseudoaneurysm alone with an AP fistula (n = 1). Successful transcatheter arterial embolization (n = 2) or percutaneous transhepatic portal vein embolization (n = 2) was performed. Embolic materials were n-butyl cyanoacrylate alone (n = 2) or in combination with gelatin sponge particles and coils (n = 2). There were no major treatment-related complications or patient mortality within 30 days. Conclusion Patients with symptomatic or life-threatening portal vein bleeding following liver-penetrating procedures can successfully be managed with embolization.

  4. Looking after your health. 3. Avoiding varicose veins.

    Science.gov (United States)

    Randall, Sara

    2015-02-01

    This article is to summarise key concepts for the health of the midwife with particular focus on standing for prolonged periods. One of the resultant factors relating to standing postures is the slow but avoidable progression of varicose veins. There is a strong genetic bias to these veins, which can be distressing, but here we will highlight awareness and current research.

  5. Retino-choroidal ischemia in central retinal vein occlusion

    OpenAIRE

    Hussain, Nazimul; Hussain, Anjli

    2014-01-01

    A 41-year-old gentleman with insulin dependent diabetes had decreased vision in the right eye due to non-ischemic central retinal vein occlusion with macular edema. One month following intravitreal ranibizumab, he developed retino-choroidal ischemia with further loss of vision. Authors show the fluorescein angiographic transition from non-ischemic central retinal vein occlusion to retino-choroidal ischemia.

  6. Optimized Axillary Vein Technique versus Subclavian Vein Technique in Cardiovascular Implantable Electronic Device Implantation: A Randomized Controlled Study

    Institute of Scientific and Technical Information of China (English)

    Peng Liu; Yi-Feng Zhou; Peng Yang; Yan-Sha Gao; Gui-Ru Zhao; Shi-Yan Ren; Xian-Lun Li

    2016-01-01

    Background:The conventional venous access for cardiovascular implantable electronic device (CIED) is the subclavian vein,which is often accompanied by high complication rate.The aim of this study was to assess the efficacy and safety of optimized axillary vein technique.Methods:A total of 247 patients undergoing CIED implantation were included and assigned to the axillary vein group or the subclavian vein group randomly.Success rate of puncture and complications in the perioperative period and follow-ups were recorded.Results:The overall success rate (95.7% vs.96.0%) and one-time success rate (68.4% vs.66.1%) of punctures were similar between the two groups.In the subclavian vein group,pneumothorax occurred in three patients.The subclavian gaps of three patients were too tight to allow operation of the electrode lead.In contrast,there were no puncture-associated complications in the axillary vein group.In the patient follow-ups,two patients in the subclavian vein group had subclavian crush syndrome and both of them received lead replacement.The incidence of complications during the perioperative period and follow-ups of the axillary vein group and the subclavian vein group was 1.6% (2/125) and 8.2% (10/122),respectively (x2=5.813,P =0.016).Conclusion:Optimized axillary vein technique may be superior to the conventional subclavian vein technique for CIED lead placement.

  7. Correlation between air pollution and crystal pattern of calcium oxalate in plant leaves of street trees in Itami City. [Ginkgo biloba; Salix babylonica; Aphananthe aspera; Robinia pseudoacacia

    Energy Technology Data Exchange (ETDEWEB)

    Umemoto, K.; Tatsumi, S.

    1975-01-01

    A characteristic difference in calcium oxalate crystal patterns in leaves of roadside trees planted in relatively unpolluted northern parts of Itami City and in parts of the city polluted by automobile exhaust was discovered. The species of trees examined were Ginkgo biloba, Salix babylonica, Aphananthe aspera, Robinia pseudoacacia, and Poplar. The leaves of trees grown in relatively less air polluted areas displayed crystal aggregates of calcium oxalate (50-80 micron) that were arranged in rows on both sides of the central vein; some scattered crystal aggregates between veins were observed. Trees grown in air polluted areas showed irregular crystal patterns and more scattering of the crystals between veins. The cause of the observed differences in the pattern of crystal aggregates was attributed to the difference in metabolism of trees under different environmental conditions. Air pollutants disturb the normal metabolism of the tree and cause hyperproduction of calcium oxalate.

  8. Disastrous Portal Vein Embolization Turned into a Successful Intervention

    Energy Technology Data Exchange (ETDEWEB)

    Dobrocky, Tomas, E-mail: tomas.dobrocky@insel.ch [University of Bern, Department of Interventional, Pediatric and Diagnostic Radiology, Inselspital, University Hospital (Switzerland); Kettenbach, Joachim, E-mail: joachim.kettenbach@stpoelten.lknoe.at [Universitätsklinikum St. Pölten-Lilienfeld, Institute of Medical Radiology, Diagnostic, Intervention (Austria); Lopez-Benitez, Ruben, E-mail: Ruben.lopez@insel.ch; Kara, Levent, E-mail: levent.kara@insel.ch [University of Bern, Department of Interventional, Pediatric and Diagnostic Radiology, Inselspital, University Hospital (Switzerland)

    2015-10-15

    Portal vein embolization (PVE) may be performed before hemihepatectomy to increase the volume of future liver remnant (FLR) and to reduce the risk of postoperative liver insufficiency. We report the case of a 71-year-old patient with hilar cholangiocarcinoma undergoing PVE with access from the right portal vein using a mixture of n-butyl-2-cyanoacrylate and ethiodized oil. During the procedure, nontarget embolization of the left portal vein occurred. An aspiration maneuver of the polymerized plug failed; however, the embolus obstructing portal venous flow in the FLR was successfully relocated into the right portal vein while carefully bypassing the plug with a balloon catheter, inflating the balloon, and pulling the plug into the main right portal vein.

  9. Finger vein image quality evaluation using support vector machines

    Science.gov (United States)

    Yang, Lu; Yang, Gongping; Yin, Yilong; Xiao, Rongyang

    2013-02-01

    In an automatic finger-vein recognition system, finger-vein image quality is significant for segmentation, enhancement, and matching processes. In this paper, we propose a finger-vein image quality evaluation method using support vector machines (SVMs). We extract three features including the gradient, image contrast, and information capacity from the input image. An SVM model is built on the training images with annotated quality labels (i.e., high/low) and then applied to unseen images for quality evaluation. To resolve the class-imbalance problem in the training data, we perform oversampling for the minority class with random-synthetic minority oversampling technique. Cross-validation is also employed to verify the reliability and stability of the learned model. Our experimental results show the effectiveness of our method in evaluating the quality of finger-vein images, and by discarding low-quality images detected by our method, the overall finger-vein recognition performance is considerably improved.

  10. Principal Component Analysis of Thermal Dorsal Hand Vein Pattern Architecture

    Directory of Open Access Journals (Sweden)

    V. Krishna Sree

    2012-12-01

    Full Text Available The quest of providing more secure identification system has lead to rise in developing biometric systems. Biometrics such as face, fingerprint and iris have been developed extensively for human identification purpose and also to provide authentic input to many security systems in the past few decades. Dorsal hand vein pattern is an emerging biometric which is unique to every individual. In this study principal component analysis is used to obtain Eigen vein patterns which are low dimensional representation of vein pattern features. The extraction of the vein patterns was obtained by morphological techniques. Noise reduction filters are used to enhance the vein patterns. Principle component analysis is able to reduce the 2-dimensional image database into 1-dimensional Eigen vectors and able to identify all the dorsal hand pattern images.

  11. Multiple vascular anomalies involving testicular, suprarenal arteries and lumbar veins

    Directory of Open Access Journals (Sweden)

    P Jyothsna

    2012-01-01

    Full Text Available Testicular arteries arise from the abdominal aorta and the inferior suprarenal artery from the renal artery. There are reports about variant origin and course of these arteries. Accessory testicular artery is also a common finding but its providing origin to inferior suprarenal artery is an important observation. During a routine dissection of abdomen of approximately 55-year-old male cadaver, unique vascular abnormality was observed. On the left side, a common arterial trunk originating from abdominal aorta immediately branched to give rise to superior testicular and inferior suprarenal arteries, the former after a short course hooked by the left suprarenal vein. In addition, the left suprarenal vein, second left lumbar vein, and left testicular vein joined to form a common trunk which drained into the left renal vein. A sound knowledge of vascular variations in relation to the kidney and suprarenal gland is important to surgeons dissecting the abdominal cavity.

  12. Design of a clinical vein contrast enhancing projector

    Science.gov (United States)

    Zeman, Herbert D.; Lovhoiden, Gunnar; Deshmukh, Harshal

    2001-06-01

    A clinical study has been initiated to compare an experimental IR device, the Vein Contrast Enhancer (VCE), with standard techniques for finding veins for venipuncture. The aims of this proposal are (1) to evaluate the performance of the VCE in a clinical setting, specifically by comparing its sensitivity of detection with existing vein-finding techniques used by experienced nurses or phlebotomists, (2) to study its usefulness in subjects who are obese, who have difficult venous access or thrombosed veins, or whose veins are not visible or difficult to palpate, and (3) to show that it performs as well on subjects with darkly pigmented skin as on subjects with lightly pigmented skin. The VCE will first be studied in adult subjects, and then in pediatric subjects.

  13. Jugular-axillary vein bypass for salvage of arteriovenous access.

    Science.gov (United States)

    Fulks, K D; Hyde, G L

    1989-01-01

    Stenosis or occlusion of the subclavian vein can cause incapacitating upper extremity swelling and venous hypertension in the patient with an arteriovenous (AV) access. A case of subclavian vein occlusion is reported that was treated with internal jugular-axillary vein bypass. This procedure resulted in salvage of the access and rapid resolution of the associated upper extremity swelling. It was concluded that jugular-axillary vein bypass should be considered in patients who have massive upper extremity edema resulting from a functioning AV access and ipsilateral subclavian vein occlusion. Patients undergoing creation of an AV access who have had previous temporary subclavian catheters or previous early failure of an AV access should have phlebography before surgery.

  14. Connexin43 Inhibition Prevents Human Vein Grafts Intimal Hyperplasia

    Science.gov (United States)

    Longchamp, Alban; Allagnat, Florent; Alonso, Florian; Kuppler, Christopher; Dubuis, Céline; Ozaki, Charles-Keith; Mitchell, James R.; Berceli, Scott; Corpataux, Jean-Marc

    2015-01-01

    Venous bypass grafts often fail following arterial implantation due to excessive smooth muscle cells (VSMC) proliferation and consequent intimal hyperplasia (IH). Intercellular communication mediated by Connexins (Cx) regulates differentiation, growth and proliferation in various cell types. Microarray analysis of vein grafts in a model of bilateral rabbit jugular vein graft revealed Cx43 as an early upregulated gene. Additional experiments conducted using an ex-vivo human saphenous veins perfusion system (EVPS) confirmed that Cx43 was rapidly increased in human veins subjected ex-vivo to arterial hemodynamics. Cx43 knock-down by RNA interference, or adenoviral-mediated overexpression, respectively inhibited or stimulated the proliferation of primary human VSMC in vitro. Furthermore, Cx blockade with carbenoxolone or the specific Cx43 inhibitory peptide 43gap26 prevented the burst in myointimal proliferation and IH formation in human saphenous veins. Our data demonstrated that Cx43 controls proliferation and the formation of IH after arterial engraftment. PMID:26398895

  15. EXPERIMENTAL STUDY OF THE MORPHOLOGY OF CEREBRAL BRIDGING VEIN

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective. To investigate the morphological properties of pig cerebral bridging vein. Methods. The morphology and fibre arrangement of 15 cerebral bridging veins obtained from 7 Danish Yorkshire landrace pigs were observed. Results. There was a narrow region at the junction of the cerebral bridging veins and superior sagittal sinus termed “ outflow cuff segment". The diameter and length of outflow cuff segment were much smaller and the thickness was higher than those of the cerebral bridging veins (P0.05). Conclusions. There were differences in fibre arrangement and morphological properties between the outflow cuff segment and the cerebral bridging vein, just like a resistance valve, the outflow cuff segment may play an important role in stabilizing cerebral venous outflow and regulating intracranial pressure.

  16. Endovascular cannulation with a microneedle for central retinal vein occlusion.

    Science.gov (United States)

    Kadonosono, Kazuaki; Yamane, Shin; Arakawa, Akira; Inoue, Maiko; Yamakawa, Tadashi; Uchio, Eiichi; Yanagi, Yasuo; Amano, Shiro

    2013-06-01

    We developed a new surgical treatment in which a microneedle is used for retinal endovascular cannulation to treat eyes with central retinal vein occlusion by flushing thrombus out of the central retinal vein as it passes through the lamina cribrosa. The eyes of 12 consecutive patients (12 eyes) with central retinal vein occlusion were successfully treated using this novel treatment. At 24 weeks after surgery, 9 of 12 eyes had gained more than 15 letters in best-corrected visual acuity, and the mean decrease in central foveal thickness was 271.1 μm. Few complications were observed. The microneedle is stiff and sharp enough to facilitate retinal endovascular cannulation in eyes with central retinal vein occlusion. This new technique is a promising treatment of macular edema due to central retinal vein occlusion.

  17. The Anatomic Course of the First Jejunal Branch of the Superior Mesenteric Vein in Relation to the Superior Mesenteric Artery

    Directory of Open Access Journals (Sweden)

    Pavlos Papavasiliou

    2012-01-01

    Full Text Available Introduction. The purpose of this study is to determine the anatomic course of the first jejunal branch of the superior mesenteric vein (SMV in relation to the superior mesenteric artery (SMA. Methods. Three hundred consecutive contrast-enhanced computed tomography (CT scans were reviewed by a surgical oncologist with confirmation of findings by a radiologist. Results. The overall incidence of a first jejunal branch coursing anterior to the SMA was 41%. There was no correlation between patient gender and position of the jejunal branch. In addition, there was no correlation between size of the first jejunal branch and its location in relation to the SMA. The IMV drained into the SMV in 27% of the patients. The IMV drained into the SMV-portal vein confluence in 17% of patients and inserted into the splenic vein in 54%. An anterior coursing first jejunal branch statistically correlated with an IMV that drained into the SMV-portal vein confluence (=0.009. Conclusion. The first jejunal branch of the SMV has a highly variable course in relation to the SMA and has a higher incidence of an anterior location in this population than previously reported.

  18. Prevalence of Splanchnic Vein Thrombosis in Pancreatitis: A Systematic Review and Meta-Analysis of Observational Studies

    Directory of Open Access Journals (Sweden)

    Wenda Xu

    2015-01-01

    Full Text Available Splanchnic vein thrombosis (SVT may be negatively associated with the prognosis of pancreatitis. We performed a systematic review and meta-analysis of literatures to explore the prevalence of SVT in pancreatitis. All observational studies regarding the prevalence of SVT in pancreatitis were identified via PubMed and EMBASE databases. The prevalence of SVT was pooled in the total of patients with pancreatitis. And it was also pooled in the subgroup analyses according to the stage and causes of pancreatitis, location of SVT, and regions where the studies were performed. After the review of 714 studies, 44 studies fulfilled the inclusion criteria. Meta-analyses showed a pooled prevalence of SVT of 13.6% in pancreatitis. According to the stage of pancreatitis, the pooled prevalence of SVT was 16.6% and 11.6% in patients with acute and chronic pancreatitis, respectively. According to the causes of pancreatitis, the pooled prevalence of SVT was 12.2% and 14.6% in patients with hereditary and autoimmune pancreatitis. According to the location of SVT, the pooled prevalence of portal vein, splenic vein, and mesenteric vein thrombosis was 6.2%, 11.2%, and 2.7% in pancreatitis. The prevalence of SVT in pancreatitis was 16.9%, 11.5%, and 8.5% in Europe, America, and Asia, respectively.

  19. [Intermittent compression of the subclavian vein].

    Science.gov (United States)

    Maraval, M

    1980-01-01

    The pathology of the cervico-thoracic channel is now well understood. Intermittent venous compression in the costo-clavicular space by the subclavian muscle can lead to acute occlusion of the venous trunk. It is important to make an early diagnosis of such compression before the stage of occlusive phlebitis. Clinical examination and dynamic phlebography allow the diagnosis to be made. Resection of the first rib is the ideal treatment. The mode of approach to the first rib is debatable since it seems that when venous symptomatology is dominant, the axillary method of Roos is not the best approach. A combined sub- and supra-clavicular approach permits a wide decompression of the vein and a more complete excision of the rib.

  20. Internal Jugular Vein Thrombosis following Oropharyngeal Infection

    Directory of Open Access Journals (Sweden)

    Asli Bostanci

    2015-01-01

    Full Text Available Internal jugular vein thrombosis (IJVT is a rare condition which may lead to life-threatening complications such as sepsis and pulmonary embolism. Prolonged central venous catheterization, intravenous (IV drug use, trauma, and radiotherapy are the most frequent causes of the IJVT. IJVT that develops after the oropharyngeal infection is a quite rare situation today. In this paper, a 37-year-old woman was presented; swelling occurred on her neck after acute tonsillitis and she was diagnosed with IJVT through Doppler ultrasonography and magnetic resonance imaging and managed without complications. Early diagnosis and conservative treatment with broad-spectrum IV antibiotics and anticoagulant agents have a critical importance for the prevention of fatal complications.

  1. Portal vein embolization before major hepatectomy

    Institute of Scientific and Technical Information of China (English)

    Hai Liu; Yong Fu

    2005-01-01

    To discuss the rationale, techniques and the unsolved issues regarding preoperative portal vein embolization (PVE) before major hepatectomy. After a systematic search of Pubmed, we reviewed and retrieved literature related to PVE. Preoperative PVE is an approach that is gaining increasing acceptance in the preoperative treatment of selected patients prior to major hepatic resection. Induction of selective hypertrophy of the nondiseased portion of the liver with PVE in patients with either primary or secondary hepatobiliary, malignancy with small estimated future liver remnants (FLR) may result in fewer complications and shorter hospital stays following resection. Additionally, PVE performed in patients initially considered unsuitable for resection due to lack of sufficient remaining normal parenchyma may add to the pool of candidates for surgical treatment. The results suggest that PVE is recomm-endable in treating the cirrhotic patients before major liver resection.

  2. Generic Network Location Service

    Directory of Open Access Journals (Sweden)

    Laban Mwansa

    2010-11-01

    Full Text Available This work presents the Generic Network Location Service based on the Chord implementation utilizing data structures called distributed hash tables (DHT or structured overlay networks, which are used to build scalable self-managing distributed systems. The provided algorithms guarantee resilience in the presence of dynamism: they guarantee consistent lookup results in the presence of nodes failing and leaving. Generic Network Location Service provides a Location Service system based on DHT technology, which is storing device location records in nodes within a Chord DHT. Location records are consisting of network device identification keys as attributes, which are used to create replicas of additional location records through established Chord hashing mechanisms. Storing device location records, in places address-able (using the DHT lookup by individual location record keys provides a simple way of implementing transla¬tion functions similar to well¬ known network services (e.g. ARP, DNS, ENUM. The generic network location ser¬vice presented in the paper is not supposed to be a substitu¬tion of the existing translation techniques (e.g. ARP, DNS, ENUM, but it is considered as an overlay service that uses data available in existing systems and provides some translations currently unavailable.

  3. Smart Location Database - Download

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Smart Location Database (SLD) summarizes over 80 demographic, built environment, transit service, and destination accessibility attributes for every census block...

  4. Smart Location Database - Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Smart Location Database (SLD) summarizes over 80 demographic, built environment, transit service, and destination accessibility attributes for every census block...

  5. Crystal Data

    Science.gov (United States)

    SRD 3 NIST Crystal Data (PC database for purchase)   NIST Crystal Data contains chemical, physical, and crystallographic information useful to characterize more than 237,671 inorganic and organic crystalline materials. The data include the standard cell parameters, cell volume, space group number and symbol, calculated density, chemical formula, chemical name, and classification by chemical type.

  6. Development of HIFU Treatment for Lower Extremity Varicose Veins

    Science.gov (United States)

    Senoo, Naohiko; Ushijima, Hiroyuki; Suzuki, Jun; Yoshinaka, Kiyoshi; Deguchi, Juno; Takagi, Shu; Miyata, Tetsuro; Matsumoto, Yoichiro

    2011-09-01

    High-intensity focused ultrasound (HIFU) has recently been developed as a noninvasive therapeutic method. In our study, a novel noninvasive therapy with HIFU was proposed for occlusion of lower extremity varicose veins. The temperature increase caused by HIFU is used to occlude varicose veins. Occluded veins became fibrotic, resulting in complete recovery. Our final goal is the medical application of HIFU treatment for varicose veins. In this study, we attempted to occlude the veins of rabbits. Prior to venous occlusion experiments, the area heated by HIFU was investigated using bovine serum albumin (BSA) gel, which denatures at >70 °C. The results indicate that the size of the heated area mainly depends on intensity at the focal point and the exposure time. A tendency was also seen for the heated area to extend toward the transducer with increasing exposure time. In animal experiments, skin burns during HIFU exposure represented a critical problem. We therefore examined the safe range of HIFU intensities in abdominal exposure experiments before conducting venous occlusion experiments. The ultrasound frequency was 1.7 MHz. Intensity at the focal point was 900 W/cm2, and the exposure time was 20 s. Rabbits underwent chemical depilation and echo gel was applied to the exposed skin to fill the boundary gap. Target veins were compressed during HIFU exposure to avoid thermal dissipation, and hyaluronan water solution was injected between the veins and skin to maintain the distance between the skin and veins at ≥5 mm. Veins were then exposed to HIFU and occluded. The capability of HIFU treatment to occlude lower extremity varicose veins was verified by the present study.

  7. A Case of Persistent Sciatic Artery Aneurysm Accompanied by a Persistent Sciatic Vein

    OpenAIRE

    Tadakoshi, Masao; Ohta, Takashi; Ishibashi, Hiroyuki; Sugimoto, Ikuo; Iwata, Hirohide; Yamada, Tetsuya; Hida, Noriyuki; Orimoto, Yuki

    2010-01-01

    A persistent sciatic artery is a rare anomaly. On the other hand, a persistent sciatic vein is frequently associated with Klippel-Trenaunay syndrome. In a 71-year-old female with a complete-type persistent sciatic artery aneurysm, we performed aneurysmectomy and right femoropopliteal bypass surgery. The right popliteal vein drained into the femoral vein via a lower-type persistent sciatic vein and the deep femoral vein. The superficial femoral artery and vein were hypoplastic. Since only 4 ca...

  8. Total anomalous connection of pulmonary veins to the portal vein. Value of multislice angiotomography. Report on three cases

    Directory of Open Access Journals (Sweden)

    Sara Alejandra Solórzano-Morales

    2014-07-01

    15 and 26% if all its varieties. Multislice angiotomography allows us to view the blood vessels and adjacent organs under consideration and obtain high-definition anatomic information. In the patients in this study, total anomalous connection of pulmonary veins to the portal vein was viewed with three-dimensional volumetric tomographic reconstructions and their correlation with ultrasonography studies.

  9. Artery and vein diameter ratio measurement based on improvement of arteries and veins segmentation on retinal images.

    Science.gov (United States)

    Hatanaka, Yuji; Tachiki, Hirokazu; Ogohara, Kazunori; Muramatsu, Chisako; Okumura, Susumu; Fujita, Hiroshi

    2016-08-01

    Retinal arteriolar narrowing is decided based on the artery and vein diameter ratio (AVR). Previous methods segmented blood vessels and classified arteries and veins by color pixels in the centerlines of blood vessels. AVR was definitively determined through measurement of artery and vein diameters. However, this approach was not sufficient for cases with close contact between the artery of interest and an imposing vein. Here, an algorithm for AVR measurement via new classification of arteries and veins is proposed. In this algorithm, additional steps for an accurate segmentation of arteries and veins, which were not identified using the previous method, have been added to better identify major veins in the red channel of a color image. To identify major arteries, a decision tree with three features was used. As a result, all major veins and 90.9% of major arteries were correctly identified, and the absolute mean error in AVRs was 0.12. The proposed method will require further testing with a greater number of images of arteriolar narrowing before clinical application.

  10. Endovenous mechanochemical ablation of great saphenous vein incompetence using the ClariVein device: a safety study

    NARCIS (Netherlands)

    Eekeren, R. van; Boersma, D.; Elias, S.; Holewijn, S.; Werson, D.A.; Vries, J.P. de; Reijnen, M.M.P.J.

    2011-01-01

    PURPOSE: To evaluate the feasibility and safety of endovenous mechanochemical ablation (MOCA) for the treatment of great saphenous vein (GSV) incompetence. METHODS: The newly developed ClariVein device uses a technique that combines mechanical endothelial damage using a rotating wire with the infusi

  11. Endovenous mechanochemical ablation of great saphenous vein incompetence using the ClariVein device: a safety study

    NARCIS (Netherlands)

    Eekeren, R. van; Boersma, D.; Elias, S.; Holewijn, S.; Werson, D.A.; Vries, J.P. de; Reijnen, M.M.P.J.

    2011-01-01

    PURPOSE: To evaluate the feasibility and safety of endovenous mechanochemical ablation (MOCA) for the treatment of great saphenous vein (GSV) incompetence. METHODS: The newly developed ClariVein device uses a technique that combines mechanical endothelial damage using a rotating wire with the

  12. Leaf hydraulic conductance varies with vein anatomy across Arabidopsis thaliana wild-type and leaf vein mutants.

    Science.gov (United States)

    Caringella, Marissa A; Bongers, Franca J; Sack, Lawren

    2015-12-01

    Leaf venation is diverse across plant species and has practical applications from paleobotany to modern agriculture. However, the impact of vein traits on plant performance has not yet been tested in a model system such as Arabidopsis thaliana. Previous studies analysed cotyledons of A. thaliana vein mutants and identified visible differences in their vein systems from the wild type (WT). We measured leaf hydraulic conductance (Kleaf ), vein traits, and xylem and mesophyll anatomy for A. thaliana WT (Col-0) and four vein mutants (dot3-111 and dot3-134, and cvp1-3 and cvp2-1). Mutant true leaves did not possess the qualitative venation anomalies previously shown in the cotyledons, but varied quantitatively in vein traits and leaf anatomy across genotypes. The WT had significantly higher mean Kleaf . Across all genotypes, there was a strong correlation of Kleaf with traits related to hydraulic conductance across the bundle sheath, as influenced by the number and radial diameter of bundle sheath cells and vein length per area. These findings support the hypothesis that vein traits influence Kleaf , indicating the usefulness of this mutant system for testing theory that was primarily established comparatively across species, and supports a strong role for the bundle sheath in influencing Kleaf .

  13. Non-cuffed dual lumen catheters in the external jugular veins versus other central veins for hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Moini Majid

    2009-01-01

    Full Text Available To compare prospective between insertion of non-cuffed dual lumen catheter in the external jugular vein and other central veins for hemodialysis (HD, we studied 68 chronic dialysis patients randomly allocated into two groups: one with external jugular vein catheterization as access for HD and another with other central venous catheterization, internal jugular or subclavian vein. Our results showed there were no significant differences regarding successful cannulation, com-plications, total numbers of dialysis, development of pain and infection at the site of cannulation, patency rate of the catheters, and efficacy of hemodialysis between both groups. In addition, the patency of the catheter in the external jugular vein was not affected by previous cannulation of other central veins. In contrast, there was a significant correlation between numbers of attempts for cannulation in both groups and development of hematoma and infection, (p< 0.05. In conclusion, our results showed that the external jugular vein may be an alternative for other central veins for insertion of temporary non-cuffed hemodialysis catheter.

  14. Factors Associated with Recurrence of Varicose Veins after Thermal Ablation: Results of The Recurrent Veins after Thermal Ablation Study

    Directory of Open Access Journals (Sweden)

    R. G. Bush

    2014-01-01

    Full Text Available Background. The goal of this retrospective cohort study (REVATA was to determine the site, source, and contributory factors of varicose vein recurrence after radiofrequency (RF and laser ablation. Methods. Seven centers enrolled patients into the study over a 1-year period. All patients underwent previous thermal ablation of the great saphenous vein (GSV, small saphenous vein (SSV, or anterior accessory great saphenous vein (AAGSV. From a specific designed study tool, the etiology of recurrence was identified. Results. 2,380 patients were evaluated during this time frame. A total of 164 patients had varicose vein recurrence at a median of 3 years. GSV ablation was the initial treatment in 159 patients (RF: 33, laser: 126, 52 of these patients had either SSV or AAGSV ablation concurrently. Total or partial GSV recanalization occurred in 47 patients. New AAGSV reflux occurred in 40 patients, and new SSV reflux occurred in 24 patients. Perforator pathology was present in 64% of patients. Conclusion. Recurrence of varicose veins occurred at a median of 3 years after procedure. The four most important factors associated with recurrent veins included perforating veins, recanalized GSV, new AAGSV reflux, and new SSV reflux in decreasing frequency. Patients who underwent RF treatment had a statistically higher rate of recanalization than those treated with laser.

  15. Fluid inclusion studies of calcite veins from Yucca Mountain, Nevada, Tuffs: Environment of formation

    Energy Technology Data Exchange (ETDEWEB)

    Roedder, E. [Harvard Univ., Cambridge, MA (United States); Whelan, J.F. [Geological Survey, Denver, CO (United States); Vaniman, D.T. [Los Alamos National Lab., NM (United States)

    1994-12-31

    Calcite vein and vug fillings at four depths (130-314m), all above the present water table in USW G-1 bore hole at Yucca Mountain, Nevada, contain primary fluid inclusions with variable vapor/liquid raitos: Most of these inclusions are either full of liquid or full of vapor. The liquid-filled inclusions show that most of the host calcite crystallized from fluids at <100{degrees}C. The vapor-filled inclusions provide evidence that a separate vapor phase was present in the fluid during crystallization. Studies of these vapor-filled inclusions on the microscope crushing stage were interpreted in an earlier paper as indicating trapping of an air-water-CO{sub 2} vapor phase at ``<100{degrees}C``. Our new studies reveal the additional presence of major methane in the vapor-filled inclusion, indicating even lower temperatures of trapping, perhaps at near-surface temperatures. They also show that the host calcite crystals grew from a flowing film of water on the walls of fractures open to the atmosphere, the vapor-filled inclusions representing bubbles that exsolved from this film onto the crystal surface.

  16. Fluid inclusion studies of calcite veins from Yucca Mountain, Nevada, Tuffs: Environment of formation

    Energy Technology Data Exchange (ETDEWEB)

    Roedder, E. [Harvard Univ., Cambridge, MA (United States); Whelan, J.F. [Geological Survey, Denver, CO (United States); Vaniman, D.T. [Los Alamos National Lab., NM (United States)

    1994-12-31

    Calcite vein and vug fillings at fourth depths (130-314m), all above the present water table in USW G-1 bore hole at Yucca Mountain, Nevada, contain primary fluid inclusions with variable vapor/liquid ratios: most of these inclusions are either full of liquid or full of vapor. The liquid-filled inclusions show that most of the host calcite crystallized from fluids at <100{degrees}C. The vapor-filled inclusions provide evidence that a separate vapor phase was present in the fluid during crystallization. Studies of these vapor-filled inclusions on the microscope crushing stage were interpreted in an earlier paper as indicating trapping of an air-water-CO{sub 2} vapor phase at {open_quotes}100{degrees}C{close_quotes}. Our new studies reveal the additional presence of major methane in the vapor-filled inclusion, indicating even lower temperatures of trapping, perhaps at near-surface temperatures. They also show that the host calcite crystals grew from a flowing film of water on the walls of fractures open to the atmosphere, the vapor-filled inclusions representing bubbles that exsolved from this film onto the crystal surface.

  17. Associations between flow in paratibial perforating veins and great saphenous vein patterns of reflux

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Engelhorn

    2015-06-01

    Full Text Available Perforating veins contribute to chronic venous valvular insufficiency (CVVI, subset of CVI of lower extremities (LE. We investigated the role of medial, proximal calf paratibial perforating veins (PTPV. Women with PTPV reflux, diameter ≥3 mm, or tortuosity were selected among 2199 LE mappings. Duplex ultrasonography (US was performed standing. Reflux >0.5 s was abnormal. PTPV conditions were related to great saphenous vein (GSV patterns of reflux. US of 442 LE of 379 women were analyzed, all being Clinical-Etiology-Anatomy-Pathophysiology (CEAP classification C1, C2, and/or having intermittent, conditional swelling. Etiology was primary. Pathophysiology was reflux, not thrombosis or obstruction. Most PTPV drained (n=281, 64% of 442 or 13% of 2199, or were source (n=73, 17%/442, 3%/2199 of GSV reflux; 49 (11%/442, 2%/2199 had reflux not associated with GSV; 39 (9%/442, 2%/2199 did not have reflux. PTPV, when significative for CVVI, primarily drained-GSV reflux. PTPV was linked to reflux in 1 of 5 and was a major source of reflux in 1 of 20 legs. Detailed US of PTPV insured over 80% accuracy in CVVI mapping.

  18. Topography of the perforating veins on the medial side of the leg (Cockett's veins).

    Science.gov (United States)

    Staubesand, J; Hackländer, A

    1995-01-01

    A macroscopic anatomical investigation was carried out on 67 embalmed dissecting-room legs in order to determine the position, course, and origin of so-called Cockett's perforating veins. This information was considered to be of particular importance because of the frequency with which varicoses in this region are treated with sclerosing agents and the serious adverse effects that can follow a misplaced injection. In view of the almost universal credence given to the accuracy of Cockett's original description (Cockett FP, 1955, Br. J. Surg. 43:260-278), and the general acceptance of the constancy of "Cockett's veins," it was felt to be of importance to see to what extent we could confirm this description. It was found that the origins of these vessels and the places at which they penetrate the deep fascia are not constant, and that--in our series--only 7.3% of the veins belonging to these groups occupy the positions that are repeatedly cited in the literature as the most common. The clinical importance of any discrepancy between expectation and reality can hardly be exaggerated.

  19. Visual disturbance following sclerotherapy for varicose veins, reticular veins and telangiectasias: a systematic literature review.

    Science.gov (United States)

    Willenberg, T; Smith, P C; Shepherd, A; Davies, A H

    2013-04-01

    The objective of the study was to review the literature reporting visual disturbance (VD)following sclerotherapy for varicose veins. Underlying mechanisms will be discussed. A literature search of the databases Medline and Google Scholar was performed. Original articles including randomized trials, case series and case reports reporting VD in humans following sclerotherapy for varicose veins were included. Additional references were also obtained if they had been referenced in related publications. The search yielded 4948 results of which 25 reports were found to meet the inclusion criteria. In larger series with at least 500 included patients the prevalence of VD following sclerotherapy ranges from 0.09% to 2%. In most reports foam sclerotherapy was associated with VD (19); exclusive use of liquid sclerosant was reported in two cases, some reports included foam and liquid sclerosant (4). There were no persistent visual disorders reported. VD occurred with polidocanol and sodium tetradecyl sulphate in different concentrations (0.25–3%). Various forms of foam preparation including various ways of foam production and the liquid –air ratio (1 or 2 parts of liquid mixed with 3, 4 or 5 parts of air) were reported in association with the occurrence of VD. VDs following sclerotherapy for varicose veins are rare and all reported events were transient. Bubble embolism or any kind of embolism seems unlikely to be the only underlying mechanism. A systemic inflammatory response following sclerotherapy has been suggested. Further research to clarify the mechanism of action of sclerosants is required.

  20. Portal Vein Inflow From Enlarged Coronary Vein in Liver Transplantation: Surgical Approach and Technical Tips: A Case Report.

    Science.gov (United States)

    Safwan, M; Nagai, S; Abouljoud, M S

    2016-11-01

    Portal vein thrombosis is common in patients with end-stage liver disease, with an incidence as high as 26% in liver transplant candidates. It is known to be associated with a high risk of morbidity and mortality posttransplantation, and its management can be challenging. The management options range from a simple thrombendvenectomy to multivisceral transplantation in cases with diffuse portomesenteric thrombosis. We report a case of liver transplantation in which we performed a rare reconstruction of the portal vein. Briefly, the patient had diffuse portomesenteric thrombosis, calcified aneurysmosis, and a large collateral coronary vein, to which we directly anastomosed the donor portal vein in an end-to-side fashion. This report describes a unique surgical approach for similar cases of severe portal vein thrombosis in liver transplant candidates.

  1. Aneurysmal dilatation of persistent vitelline vein with thrombus in a neonate

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Kun Woo; Sung, Deuk Jae; Park, Beom Jin; Kim, Min Ju; Cho, Sung Bum [Korea University College of Medicine, Department of Radiology, Anam Hospital, Seoul (Korea, Republic of)

    2014-07-15

    The paired vitelline veins selectively involute and form a part of the portal vein during embryonic development. The presence of a persistent vitelline vein segment after birth is very rare and can be confused with anomalies of the portal and umbilical veins. We present sonographic, CT and MRI findings of aneurysmal dilatation of a persistent vitelline vein with thrombus in a neonate; this case was first misdiagnosed as an umbilical vein varix by prenatal US. MRI was used to identify the persistent vitelline vein segment and the remnant umbilical vein segment. (orig.)

  2. Industrial location and competitiveness

    NARCIS (Netherlands)

    S. Brakman (Steven); J.H. Garretsen (Harry); J.G.M. van Marrewijk (Charles)

    2006-01-01

    textabstractThe interaction between the extent of location advantages and the intensity of firm competition relative to the size of the market jointly determines the location of industrial activity. Technology, factor endowments, geography, and scale economies are influential for determining locatio

  3. Appraising manufacturing location

    NARCIS (Netherlands)

    Steenhuis, Harm-Jan; Bruijn, de Erik J.

    2002-01-01

    International location of manufacturing activities is an issue for managers of manufacturing companies as well as public policy makers. For managers, the issue is relevant because international locations offer opportunities for lowering costs due to productivity improvements. For governments the iss

  4. Assessing manufacturing location

    NARCIS (Netherlands)

    Steenhuis, Harm-Jan; Bruijn, de Erik J.

    2004-01-01

    International location of manufacturing activities is an issue for managers of manufacturing companies as well as public policy-makers. For managers, the issue is relevant because international locations offer opportunities for lowering costs due to productivity improvements. For governments the iss

  5. Nanostructured porous silicon photonic crystal for applications in the infrared

    OpenAIRE

    G. Recio-Sánchez; Torres-Costa, V.; Manso-Silván, M.; R. J. Martín-Palma

    2012-01-01

    In the last decades great interest has been devoted to photonic crystals aiming at the creation of novel devices which can control light propagation. In the present work, two-dimensional (2D) and three-dimensional (3D) devices based on nanostructured porous silicon have been fabricated. 2D devices consist of a square mesh of 2 μm wide porous silicon veins, leaving 5×5 μm square air holes. 3D structures share the same design although multilayer porous silicon veins are used instead, providing ...

  6. The Compartment Syndrome Associated with Deep Vein Thrombosis due to Rattlesnake Bite: A Case Report.

    Science.gov (United States)

    Tincu, Radu Ciprian; Ghiorghiu, Zoie; Tomescu, Dana; Macovei, Radu Alexandru

    2017-08-04

    Snakebite is a health issue specific to some parts of the world, especially in the tropical areas, where it produces many victims. The main clinical damage caused by snakebite involves haemotoxic, neurotoxic and myotoxic reactions. We report the case of a young woman suffering from snakebite who developed deep vein thrombosis and compartment syndrome. We present the case of a 32-year-old Romanian woman who was injured by her own Crotalinae snake (also known as pit viper or rattlesnake) on her left forearm. When admitted to our Emergency Department, she was conscious with a Glasgow coma scale of 12/15, somnolent, febrile, suffering of headache, tachypnoea; the marks of the snakebite were located in the distal part of the anterior left forearm; she had pain and bleeding at the bite site and swelling of the left upper limb with lymphangitis up to the axilla. She experienced fasciotomy-requiring compartment syndrome of the upper limb and required unfractionated heparin and close monitoring using activated partial thromboplastin time evolution due to micro-thrombosis in the brachial vein. Local improvement was achieved in the next 4 days with progressive diminishment of local tenderness and swelling. Limb deep vein thrombosis might be induced by snakebite, despite the pro-haemorrhagic general condition induced by the envenomation. A high index of clinical suspicion is needed for early diagnosis and timely management, which can improve survival of these patients.

  7. Role of Excessive Autophagy Induced by Mechanical Overload in Vein Graft Neointima Formation: Prediction and Prevention

    Science.gov (United States)

    Chang, Ya-Ju; Huang, Hui-Chun; Hsueh, Yuan-Yu; Wang, Shao-Wei; Su, Fong-Chin; Chang, Chih-Han; Tang, Ming-Jer; Li, Yi-Shuan; Wang, Shyh-Hau; Shung, Kirk K.; Chien, Shu; Wu, Chia-Ching

    2016-02-01

    Little is known regarding the interplays between the mechanical and molecular bases for vein graft restenosis. We elucidated the stenosis initiation using a high-frequency ultrasonic (HFU) echogenicity platform and estimated the endothelium yield stress from von-Mises stress computation to predict the damage locations in living rats over time. The venous-arterial transition induced the molecular cascades for autophagy and apoptosis in venous endothelial cells (ECs) to cause neointimal hyperplasia, which correlated with the high echogenicity in HFU images and the large mechanical stress that exceeded the yield strength. The ex vivo perfusion of arterial laminar shear stress to isolated veins further confirmed the correlation. EC damage can be rescued by inhibiting autophagy formation using 3-methyladenine (3-MA). Pretreatment of veins with 3-MA prior to grafting reduced the pathological increases of echogenicity and neointima formation in rats. Therefore, this platform provides non-invasive temporal spatial measurement and prediction of restenosis after venous-arterial transition as well as monitoring the progression of the treatments.

  8. Superior Mesenteric Vein Occlusion Causing Severe Gastrointestinal Haemorrhage in Two Paediatric Cases

    Directory of Open Access Journals (Sweden)

    Anna L. Fox

    2012-01-01

    Full Text Available Reports about superior mesenteric vein thrombosis in childhood are very rare and have not been associated with gastrointestinal bleeding. We describe two cases of severe bleeding from the upper and lower gastrointestinal tract in children who had undergone complex abdominal surgery at considerable time before. The first child had a tracheoesophageal fistula, corrected by division, gastrostomy insertion, and repair of duodenal rupture. The child presented with severe bleeding from the gastrostomy site and was diagnosed with a thrombosis of the proximal superior mesenteric vein. The second child had a gastroschisis and duodenal atresia, and required duodenoplasty, gastrostomy insertion, hemicolectomy, and adhesiolysis. The child presented with intermittent severe lower gastrointestinal bleeding, resulting from collateral vessels at location of the surgical connections. He was diagnosed with a thrombosis of the superior mesenteric vein. In both children, the extensive previous surgery and anastomosis were considered the cause of the mesenteric thrombosis. CT angiography confirmed the diagnosis in both cases, in addition to characteristic findings on endoscopy. Paediatricians should suspect this condition in children with severe gastrointestinal bleeding, particularly in children with previous, complex abdominal surgery.

  9. Macromolecular crystallization and crystal perfection

    CERN Document Server

    Chayen, Naomi E; Snell, Edward H

    2010-01-01

    Structural biology is key to our understanding of the mechanisms of biological processes. This text describes current methods and future frontiers in crystal growth and use of X-ray and neutron crystallography, in the context of automation of crystallization and generation of synchrotron X-ray and neutron beams.

  10. Liquid crystal tunable photonic crystal dye laser

    DEFF Research Database (Denmark)

    Buss, Thomas; Christiansen, Mads Brøkner; Smith, Cameron

    2010-01-01

    We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium....

  11. Thermographic visualization of the superficial vein and extravasation using the temperature gradient produced by the injected materials

    Science.gov (United States)

    Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Yoshitake, Tadamasa; Terashima, Kotaro; Asai, Kaori; Matsumoto, Keiji; Shinoto, Makoto; Shioyama, Yoshiyuki; Nishie, Akihoro; Honda, Hiroshi

    2014-11-01

    There are few effective methods to detect or prevent the extravasation of injected materials such as chemotherapeutic agents and radiographic contrast materials. To investigate whether a thermographic camera could visualize the superficial vein and extravasation using the temperature gradient produced by the injected materials, an infrared thermographic camera with a high resolution of 0.04 °C was used. At the room temperature of 26 °C, thermal images and the time course of the temperature changes of a paraffin phantom embedded with rubber tubes (diameter 3.2 mm, wall thickness 0.8 mm) were evaluated after the tubes were filled with water at 15 °C or 25 °C. The rubber tubes were embedded at depths of 0 mm, 1.5 mm, and 3.0 mm from the surface of the phantom. Temperature changes were visualized in the areas of the phantom where the tubes were embedded. In general, changes were more clearly detected when greater temperature differences between the phantom and the water and shallower tube locations were employed. The temperature changes of the surface of a volunteer's arm were also examined after a bolus injection of physiological saline into the dorsal hand vein or the subcutaneous space. The injection of 5 ml room-temperature (26 °C) saline into the dorsal hand vein enabled the visualization of the vein. When 3 ml of room-temperature saline was injected through the vein into the subcutaneous space, extravasation was detected without any visualization of the vein. The subtraction image before and after the injection clearly showed the temperature changes induced by the saline. Thermography may thus be useful as a monitoring system to detect extravasation of the injected materials.

  12. Microperimetric changes after intravitreal triamcinolone acetonide injection for macular edema due to central retinal vein occlusion.

    Science.gov (United States)

    Senturk, Fevzi; Ozdemir, Hakan; Karacorlu, Murat; Karacorlu, Serra Arf; Uysal, Omer

    2010-09-01

    The purpose of this study was to evaluate the effect of intravitreal triamcinolone acetonide on macular function in cases of macular edema because of central retinal vein occlusion. Twelve eyes of 12 patients with central retinal vein occlusion were included in this study. In each eye, at baseline and 1, 3, and 6 months after intravitreal triamcinolone acetonide injection, logarithm of the minimum angle of resolution visual acuity, macular sensitivity, fixation stability and fixation location by MP-1 microperimetry, and foveal thickness by optical coherence tomography were assessed. Patients' ages ranged from 50 to 75 years (mean +/- SD, 59 +/- 8 years). All patients were classified as nonischemic. At 1, 3, and 6 months, the mean foveal thickness had decreased from 453 +/- 108 microm to 254 +/- 40.3 microm, 297 +/- 90 microm, and 320 +/- 82 microm and the mean retinal sensitivity had increased from 5.5 +/- 3.3 dB to 9.4 +/- 3.5 dB, 7.8 +/- 3.3 dB, and 7.2 +/- 4.2 dB, respectively. At baseline, fixation was stable in one, relatively unstable in six, and unstable in five eyes. However, 6 months after intravitreal triamcinolone acetonide injection, fixation was stable in 8, relatively unstable in 3, and unstable in one. At baseline, in eyes with macular edema, fixation location was predominantly central in 2, poor central in 4, and predominantly eccentric in 6. And 6 months after treatment, fixation location was predominantly central in 8, poor central in 3, and predominantly eccentric in 1. In eyes with macular edema in central retinal vein occlusion, a short-term improvement in retinal sensitivity and fixation properties can be achieved by intravitreal triamcinolone acetonide injection.

  13. Finger vein verification system based on sparse representation.

    Science.gov (United States)

    Xin, Yang; Liu, Zhi; Zhang, Haixia; Zhang, Hong

    2012-09-01

    Finger vein verification is a promising biometric pattern for personal identification in terms of security and convenience. The recognition performance of this technology heavily relies on the quality of finger vein images and on the recognition algorithm. To achieve efficient recognition performance, a special finger vein imaging device is developed, and a finger vein recognition method based on sparse representation is proposed. The motivation for the proposed method is that finger vein images exhibit a sparse property. In the proposed system, the regions of interest (ROIs) in the finger vein images are segmented and enhanced. Sparse representation and sparsity preserving projection on ROIs are performed to obtain the features. Finally, the features are measured for recognition. An equal error rate of 0.017% was achieved based on the finger vein image database, which contains images that were captured by using the near-IR imaging device that was developed in this study. The experimental results demonstrate that the proposed method is faster and more robust than previous methods.

  14. Renal Vein Reconstruction for Harvesting Injury in Kidney Transplantation

    Directory of Open Access Journals (Sweden)

    Birkan Bozkurt

    2014-03-01

    Full Text Available Kidney transplantation is the best treatment choice in the end-stage renal disease. In the renal transplantation, renal vein damage or shortness which occurs during cadaveric or living donor nephrectomy causes technical difficulties for surgeons. The lack of the donors already especially cadaveric, the acquirement of the graft, gets very much importance. In this report, it is aimed to share the clinical experiment by which it seen, how anastomosis can become appropriate by using the renal vein which is damaged in the way that anastomosis cannot be done anyway by using cadaveric vena cava graft. The renal vein brought to length for anostomosis which is repaired by using cadaveric vena cava graft, is anastomosed successfully by becoming an end-to-side of the external iliac vein of the recipient. Vascular anastomoses are applied easily in technique. The time of the warm ischemia was under 2 hours and the kidney was functional in the post-operative period. Renal vein trombosis was not observed. The renal vein damage occured during cadaveric or living donor nephrectomy, can be repaired by some methods. In the kidneys in which vein requirement is done, the success rates are rather high although acute tubular necrosis and delayed function can be seen more.

  15. Vestibular tributaries to the vein of the vestibular aqueduct.

    Science.gov (United States)

    Hansen, Jesper Marsner; Qvortrup, Klaus; Friis, Morten

    2011-01-01

    The vein of the vestibular aqueduct drains blood from areas extensively lined by vestibular dark cells (VDCs). A possible involvement in the pathogenesis of an impaired endolymphatic homeostasis can be envisioned at the level of the dark cells area. The aim of this study was to investigate the vascular relationship between the vein of the vestibular aqueduct and the vestibular apparatus, with focus on the VDCs. Sixteen male Wistar rats were divided into groups of 6 and 10. In the first group, 2 μm thick sections including the vein of the vestibular aqueduct, utricle, and crista ampullaris of the lateral ampulla were examined by light microscopy and computer-generated three-dimensional imaging. In the second group, ultrathin sections including venules and VDCs were examined by transmission electron microscopy. A microvascular network was observed in close relation to the VDCs in the utricle and the crista ampullaris of the lateral semicircular canal in the vestibular apparatus. One major vein emanated from these networks, which emptied into the vein of the vestibular aqueduct. Veins draining the saccule and the common crus of the superior and posterior semicircular canals were likewise observed to merge with the vein of the vestibular aqueduct.

  16. Leaf Vein Extraction Based on Gray-scale Morphology

    Directory of Open Access Journals (Sweden)

    Xiaodong Zheng

    2010-12-01

    Full Text Available Leaf features play an important role in plant species identification and plant taxonomy. The type of the leaf vein is an important morphological feature of the leaf in botany. Leaf vein should be extracted from the leaf in the image before discriminating its type. In this paper a new method of leaf vein extraction has been proposed based on gray-scale morphology. Firstly, the color image of the plant leaf is transformed to the gray image according to the hue and intensity information. Secondly, the gray-scale morphology processing is applied to the image to eliminate the color overlap in the whole leaf vein and the whole background. Thirdly, the linear intensity adjustment is adopted to enlarge the gray value difference between the leaf vein and its background. Fourthly, calculate a threshold with OSTU method to segment the leaf vein from its background. Finally, the leaf vein can be got after some processing on details. Experiments have been conducted with several images. The results show the effectiveness of the method. The idea of the method is also applicable to other linear objects extraction.

  17. Life without the vein of Galen: Clinical and radiographic sequelae.

    Science.gov (United States)

    Youssef, A Samy; Downes, Angela E; Agazzi, Siviero; Van Loveren, Harry R

    2011-09-01

    A thorough understanding of the anatomy of the pineal region, particularly venous drainage, is critical for gaining open surgical access to the pineal gland. The adverse sequelae after intraoperative venous occlusion are assumed to be catastrophic but have been scarcely reported. We report a case of pineocytoma in which the vein of Galen was ligated without postoperative adverse sequelae. Pineal region anatomy with emphasis on deep veins was reviewed in large anatomical studies. There are tremendous anatomical variations in the vein of Galen and its tributaries. Several confounding factors can be encountered during surgery and may lead to accidental sacrifice of the vein of Galen. Survival after focal occlusion of a major deep vein depends on the development of collateral circulation as shown in our case report. Venous drainage remains the cornerstone in the surgical planning of the pineal region. Anatomical variations and venous collaterals undoubtedly contributed to the mixed reports of adverse sequelae after venous sacrifice. Vein of Galen ligation may be survivable but consequences cannot be predicted without a thorough pre-ligation assessment of regional venous collateral drainage. Thorough understanding of the venous anatomy, meticulous planning of the surgical approach and avoidance of the occlusion of the vein of Galen and its major tributaries are key factors to successful pineal region surgery.

  18. [RADIOFREQUENCY ABLATION FOR THE TREATMENT OF VARICOSE VEINS].

    Science.gov (United States)

    Sugiyama, Satoru; Miyade, Yoshio; Inaki, Yasuhiko

    2015-05-01

    Significant advances in the endovenous technique for treating incompetent saphenous veins could change the surgical strategy in patients with varicose veins. Radiofrequency ablation (RFA) was approved as a new technique for the treatment of varicose veins in Japan in June 2014. In RFA, the ablation temperature is controlled by a sensor at the upper end of the catheter. The vein wall is heated with stable conductive power of 120 degrees C, resulting in endothelial denudation. The RFA method was approved in 1998 in Europe and in 1999 in the USA. The ClosurePLUS catheter was developed in 2003 and ClosureFAST in 2006. High occlusion rates and lower postoperative complication rates were reported with ClosureFAST than with ClosurePLUS. It is expected that this new ablation technique will control saphenous vein reflux with less pain and less ecchymosis after surgery. The treatment of varicose veins is less invasive with RFA devices and will become widely accepted as an alternative to conventional surgery for varicose veins in Japan.

  19. Magma chamber cooling by episodic volatile expulsion as constrained by mineral vein distributions in the Butte, Montana Cu-Mo porphyry deposit

    Science.gov (United States)

    Daly, K.; Karlstrom, L.; Reed, M. H.

    2016-12-01

    The role of hydrothermal systems in the thermal evolution of magma chambers is poorly constrained yet likely significant. We analyze trends in mineral composition, vein thickness and overall volumetric fluid flux of the Butte, Montana porphyry Cu-Mo deposit to constrain the role of episodic volatile discharge in the crystallization of the source magma chamber ( 300 km3of silicic magma). An aqueous fluid sourced from injection of porphyritic dikes formed the Butte porphyry Cu network of veins. At least three separate pulses of fluid through the system are defined by alteration envelopes of [1] gray sericite (GS); [2] early-dark micaceous (EDM), pale-green sericite (PGS), and dark-green sericite (DGS); and [3] quartz-molybdenite (Qmb) and barren-quartz. Previous research using geothermometers and geobarometers has found that vein mineral composition, inferred temperatures and inferred pressures vary systematically with depth. Later fluid pulses are characterized by lower temperatures, consistent with progressive cooling of the source. We have digitized previously unused structural data from Butte area drill cores, and applied thermomechanical modeling of fluid release from the source magma chamber through time. Vein number density and vein thickness increase with depth as a clear function of mineralogy and thus primary temperature and pressure. We identify structural trends in the three fluid pulses which seem to imply time evolution of average vein characteristics. Pulses of Qmb-barren quartz and EDM-PGS-DGS (1st and 2nd in time) exhibit increasing vein number density (157 & 95 veins/50m, respectively) and thickness (300mm & 120mm, respectively) as a function of depth. EDM-PGS-DGS has a shallower peak in vein density (800m) than Qmb-barren quartz (>1600m). These data provide the basis for idealized mechanical models of hydrofractures, to predict driving pressures and to compare with existing source temperatures and total fluid volumes in order to estimate the total

  20. Crystal Dislocations

    Directory of Open Access Journals (Sweden)

    Ronald W. Armstrong

    2016-01-01

    Full Text Available Crystal dislocations were invisible until the mid-20th century although their presence had been inferred; the atomic and molecular scale dimensions had prevented earlier discovery. Now they are normally known to be just about everywhere, for example, in the softest molecularly-bonded crystals as well as within the hardest covalently-bonded diamonds. The advent of advanced techniques of atomic-scale probing has facilitated modern observations of dislocations in every crystal structure-type, particularly by X-ray diffraction topography and transmission electron microscopy. The present Special Issue provides a flavor of their ubiquitous presences, their characterizations and, especially, their influence on mechanical and electrical properties.

  1. Localization of sympathetic postganglionic neurons innervating mesenteric artery and vein in rats.

    Science.gov (United States)

    Hsieh, N K; Liu, J C; Chen, H I

    2000-04-12

    Physiological and histochemical studies have demonstrated the control and innervation of sympathetic nerves to the artery and vein vessels of splanchnic circulation. In our laboratory, we first used the technique of retrograde transport of horseradish peroxidase to identify the origin of sympathetic neurons innervating the mesenteric vein. In this study, double fluorescence staining technique was used for a simultaneous localization of the sympathetic postganglionic neurons supplying the mesenteric artery and vein in rats. First-order branches of mesenteric artery (A) and vein (V) in the vicinity of ileo-cecal junction were isolated for application of fluorescent dyes (Fast Blue, FB and Diamidino Yellow, DY). The application of FB and DY on A and V was alternated in the next animal to minimize the difference in dye uptake. The animal was allowed to recover for 6-7 days assuring a complete uptake of FB and DY into the cytoplasm and nucleus, respectively. The number of FB, DY and double staining neurons in the prevertebral and paravertebral ganglia were counted under a fluorescent microscope after animal fixation and serial frozen section (30 microm) of the sympathetic ganglia. Our study revealed the following findings: (1) Distribution of the fluorescence-staining neurons in the sympathetic ganglia was as follows: right celiac ganglion (39%), superior mesenteric ganglion (30%), left celiac ganglion (26%), inferior mesenteric ganglion (1%) and paravertebral ganglia (4%). (2) Double staining neurons that dually innervate A and V amounted to 54% of total staining neurons. There were 41% neurons singly innervating A and 5% innervating V. (3) The ratio of neurons supplying the A and V ranged from 1.41 to 1.75 (average 1.61). (4) There was no distinct topographical distribution with respect to the neuron location innervating A and V. The distribution of neurons appeared in a scattering pattern.

  2. Portal vein arterialization increases hepatocellular apoptosis and inhibits liver regeneration.

    Science.gov (United States)

    Schleimer, Karina; Stippel, Dirk L; Kasper, Hans U; Prenzel, Klaus; Gaudig, Cindy; Tawadros, Samir; Hoelscher, Arnulf H; Beckurts, K Tobias E

    2008-10-01

    Portal vein arterialization is performed in particular situations to guarantee sufficient blood flow in the portal vein. In addition, some authors have postulated a proliferation-promoting influence of portal vein arterialization on the liver tissue. However, portal vein arterialization is an unphysiological procedure: It increases portal blood flow and blood pressure as well as oxygenation of the liver tissue. On the other hand, it reduces the influx of hepatotrophic factors from the portal venous blood. The aim of these experiments was to investigate apoptosis and proliferation of hepatocytes during various conditions of the portal perfusion. After 70% liver resection in Lewis rats, the following four experimental groups were formed differing in portal perfusion: (I) hyperperfused, nonarterialized; (II) flow-regulated, nonarterialized; (III) hyperperfused, arterialized; (IV) flow-regulated, arterialized. A warm ischemia of 30 min was kept in all groups. Portal vein arterialization of 70% reduced rat livers significantly reduced liver regeneration as shown by a significant reduction in liver weight, body weight, and liver function after 6 wk, in contrast to the group with 70% liver mass reduction and portal venous inflow of the portal vein. Furthermore, we found a significantly elevated number of apoptotic hepatocytes after portal vein arterialization. These results were independent from blood flow regulation of the arterialized portal vein, which caused no improvement of the results. Portal vein arterialization should be performed only temporarily and is clinically not recommended as a permanent option, because of the increased hepatocellular apoptosis and the very distinctive, negative long-term effects on liver weight.

  3. Postpartum ovarian vein thrombosis after cesarean delivery: a case report

    Directory of Open Access Journals (Sweden)

    Royo Pedro

    2008-04-01

    Full Text Available Abstract Introduction Postpartum ovarian vein thrombosis is an uncommon complication; incidence varies between 0.002% and 0.05%. It most often occurs during the 2–15 days following delivery. Case presentation A 22-year-old pregnant woman at term presented to hospital with uterine contractions, abdominal pain, nausea and vomiting. After delivery an ovarian vein thrombosis was diagnosed. Conclusion Low-molecular weight heparin with broad-spectrum antibiotics are the accepted therapy in non-complicated cases of postpartum ovarian vein thrombosis.

  4. Postpartum ovarian vein thrombosis after cesarean delivery: a case report

    Science.gov (United States)

    Royo, Pedro; Alonso-Burgos, Alberto; García-Manero, Manuel; Lecumberri, Ramón; Alcázar, Juan Luis

    2008-01-01

    Introduction Postpartum ovarian vein thrombosis is an uncommon complication; incidence varies between 0.002% and 0.05%. It most often occurs during the 2–15 days following delivery. Case presentation A 22-year-old pregnant woman at term presented to hospital with uterine contractions, abdominal pain, nausea and vomiting. After delivery an ovarian vein thrombosis was diagnosed. Conclusion Low-molecular weight heparin with broad-spectrum antibiotics are the accepted therapy in non-complicated cases of postpartum ovarian vein thrombosis. PMID:18400095

  5. Duodenal obstruction due to a preduodenal portal vein

    Directory of Open Access Journals (Sweden)

    MNC Vilakazi

    2014-01-01

    Full Text Available An infant presented with clinical signs and symptoms suggestive of a pyloric stenosis. On abdominal ultrasound, pyloric stenosis was excluded, and other causes for proximal duodenal obstruction, such as a duodenal web or annular pancreas, were suspected. At surgery, the cause was found to be due to an anterior portal vein or preduodenal portal vein, compressing the duodenum. There were no associated findings such as midgut malrotation, duodenal web and congenital anomalies. The treatment was a diamond-shaped duodeno-duodenostomy anterior to the portal vein. The patient improved after surgery.

  6. [Oclusion of upper ophthalmic vein--a case report].

    Science.gov (United States)

    Kácerik, M; Alexík, M; Lipková, B

    2009-07-01

    Thrombosis of upper ophthalmic vein is both rare and serious pathologic event. Authors present a case of isolated unilateral upper ophthalmic vein thrombosis in 76-year-old woman, who despite treatment ended with amaurosis and secondary neovascular glaucoma. In differential diagnosis authors focused on searching for inflammatory process of orbit with adjacent structures as well as local and general causes leading to venous thrombosis. None of these were proven; it was a rare case of a patient with isolated upper ophthalmic vein thrombosis.

  7. Splenic Vein Leiomyosarcoma: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Damiano Patrono

    2014-09-01

    Full Text Available Context Primary venous leiomyosarcoma (LMS is a rare disease, most commonly affecting the retroperitoneal veins and in particular the inferior vena cava. Five-year survival rate ranges between 33% and 68%. Case Report Complete surgical resection represents the only potentially curative treatment, occasionally achieving long-term survival. LMS of the splenic vein is extremely rare, with only three cases reported in the literature. Conclusion We report a case of primary venous LMS arising from the splenic vein and we briefly review the relevant literature.

  8. Pylephlebitis of a variant mesenteric vein complicating sigmoid diverticulitis.

    Science.gov (United States)

    Falkowski, Anna L; Cathomas, Gieri; Zerz, Andreas; Rasch, Helmut; Tarr, Philip E

    2014-02-01

    Pylephlebitis--suppurative thrombophlebitis of the portal and/or mesenteric veins--is a rare complication of abdominal infections, especially diverticulitis. It can lead to severe complications such as hepatic abscess, sepsis, peritonitis, bowel ischemia, etc., which increase the mortality rate. Here we present a case of suppurative thrombophlebitis of the inferior mesenteric vein, as a complication of sigmoid diverticulitis. The epidemiology, clinical and radiological features as well as treatment strategies are discussed. We also review the anatomy of the mesenteric vein given its anatomic variation in the present case and how this anatomic knowledge might influence the operative approach should surgery be necessary.

  9. Combined arteriovenous thrombolytic infusion for refractory renal vein thrombosis.

    Science.gov (United States)

    Heafner, Thomas A; Scott, Daniel; Watson, J Devin; Propper, Brandon; Johnson, Chatt; Arthurs, Zachary M

    2014-08-01

    Acute renal vein thrombosis can rapidly lead to significant impairment and eventual loss of renal function. Classically presenting with flank pain, hematuria, and laboratory markers consistent with acute kidney injury, therapeutic anticoagulation is the mainstay of treatment. However, endovascular surgery offers a safe and effective alternative for renal salvage in the setting of acute renal vein thrombosis. Described is the use of combined arteriovenous thrombolytic infusion for refractory renal vein thromboses to quickly and effectively decrease clot burden in the micro- and macrovenous circulations while limiting systemic exposure.

  10. Unusual Presentation of Renal Vein Thrombosis in a Preterm Infant.

    Science.gov (United States)

    Yang, Chang-Yo; Fu, Ren-Huei; Lien, Reyin; Yang, Peng-Hong

    2014-05-01

    Neonatal renal vein thrombosis is the most common vascular condition in the newborn kidney, which could lead to serious complication in infants undergoing intensive care. In this study, we report the case of a preterm infant with left renal vein and inferior vena cava thrombosis, presented with gross hematuria, thrombocytopenia, transient hypertension, and adrenal hemorrhage. Supportive care was offered instead of heparin therapy or thrombolytic agents. In conclusion, our case teaches that, despite the lack of a clinically obvious shock event, renal vein thrombosis should be considered in a macrohematuric newborn without renal failure.

  11. Ovarian Vein Thrombosis as a Complication of Laparoscopic Surgery.

    Science.gov (United States)

    Gupta, Anu; Gupta, Natasha; Blankstein, Josef; Trester, Richard

    2015-01-01

    Ovarian vein thrombosis (OVT) is an extremely rare but life-threatening complication of the postpartum period. It has never been reported as a complication of laparoscopic surgery. We report a case of right ovarian vein thrombosis that occurred in the postoperative period after patient underwent laparoscopic salpingectomy for a right side ectopic pregnancy. She presented with 1-week history of abdominal pain and fever. A complete workup for fever was performed and was found negative. Computed tomography of the abdomen and pelvis revealed right ovarian vein thrombosis. The patient was treated with anticoagulant therapy and responded well.

  12. Ovarian Vein Thrombosis as a Complication of Laparoscopic Surgery

    Directory of Open Access Journals (Sweden)

    Anu Gupta

    2015-01-01

    Full Text Available Ovarian vein thrombosis (OVT is an extremely rare but life-threatening complication of the postpartum period. It has never been reported as a complication of laparoscopic surgery. We report a case of right ovarian vein thrombosis that occurred in the postoperative period after patient underwent laparoscopic salpingectomy for a right side ectopic pregnancy. She presented with 1-week history of abdominal pain and fever. A complete workup for fever was performed and was found negative. Computed tomography of the abdomen and pelvis revealed right ovarian vein thrombosis. The patient was treated with anticoagulant therapy and responded well.

  13. Endovenous radiofrequency ablation for the treatment of varicose veins.

    Science.gov (United States)

    Kayssi, Ahmed; Pope, Marc; Vucemilo, Ivica; Werneck, Christiane

    2015-04-01

    Varicose veins are a common condition that can be treated surgically. Available operative modalities include saphenous venous ligation and stripping, phlebectomy, endovenous laser therapy and radiofrequency ablation. Radiofrequency ablation is the newest of these technologies, and to our knowledge our group was the first to use it in Canada. Our experience suggests that it is a safe and effective treatment for varicose veins, with high levels of patient satisfaction reported at short-term follow-up. More studies are needed to assess long-term effectiveness and compare the various available treatment options for varicose veins.

  14. Use of bovine mesenteric vein in rescue vascular access surgery.

    Science.gov (United States)

    Benedetto, Filippo; Carella, Giuseppe; Lentini, Salvatore; Barillà, David; Stilo, Francesco; De Caridi, Giovanni; Spinelli, Francesco

    2010-01-01

    We describe a technique for rescue surgery of autologous arterovenous fistula (AVF), using bovine mesenteric vein (BMV), which may be used in patients with autologous AVF malfunction caused by steno-occlusion on the arterial side or by fibrosis of the first portion of the vein. To preserve the autologous AVF, we replaced the diseased portion of the artery, or the first centimeters of the vein, by a segment of BMV, with the aim of saving the patency and functionality of the access. We used this technique in 16 cases. All patients underwent hemodialysis treatment immediately after the procedure. Infection or aneurismal dilatation of the graft in implanted BMV was never observed.

  15. Smart Location Mapping

    Science.gov (United States)

    The Smart Location Database, Access to Jobs and Workers via Transit, and National Walkability Index tools can help assess indicators related to the built environment, transit accessibility, and walkability.

  16. Waste Recovery Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Locations where City residents are encouraged to drop off and dispose or recycle of unwanted materials. Information provided is subject to change. Please call ahead...

  17. Electronic apex locators.

    Science.gov (United States)

    Gordon, M P J; Chandler, N P

    2004-07-01

    Prior to root canal treatment at least one undistorted radiograph is required to assess canal morphology. The apical extent of instrumentation and the final root filling have a role in treatment success, and are primarily determined radiographically. Electronic apex locators reduce the number of radiographs required and assist where radiographic methods create difficulty. They may also indicate cases where the apical foramen is some distance from the radiographic apex. Other roles include the detection of root canal perforation. A review of the literature focussed first on the subject of electronic apex location. A second review used the names of apex location devices. From the combined searches, 113 pertinent articles in English were found. This paper reviews the development, action, use and types of electronic apex locators.

  18. Allegheny County Dam Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the point locations of dams in Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  19. VT Hospital Site Locations

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This data layer contains point locations of all major community, regional, comprehensive health, and healthcare provider hospitals in the state of...

  20. IHS Facility Locator

    Data.gov (United States)

    U.S. Department of Health & Human Services — This map can be used to find an Indian Health Service, Tribal or Urban Indian Health Program facility. This map can be used to: Zoom in to a general location to...

  1. USAID Activity Locations

    Data.gov (United States)

    US Agency for International Development — The USAID Activities dataset is a snapshot of activities supported by USAID including their geographical locations within countries at the time of the snapshot. The...

  2. Eldercare Locator Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Eldercare Locator is a searchable database that allows a user to search via zip code or city/ state for agencies at the State and local levels that provide...

  3. Uranium Location Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — A GIS compiled locational database in Microsoft Access of ~15,000 mines with uranium occurrence or production, primarily in the western United States. The metadata...

  4. Global Volcano Locations Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC maintains a database of over 1,500 volcano locations obtained from the Smithsonian Institution Global Volcanism Program, Volcanoes of the World publication. The...

  5. HAFNIUM IMPLANTED IN IRON .1. LATTICE LOCATION AND ANNEALING BEHAVIOR

    NARCIS (Netherlands)

    DEBAKKER, JMGJ; PLEITER, F; SMULDERS, PJM

    1993-01-01

    Perturbed angular correlation, Rutherford backscattering and channelling experiments were conducted to study the lattice location and annealing behaviour of 110 keV hafnium ions implanted into iron single crystals. It was found that a fraction of 11-25% of the implanted hafnium atoms are located at

  6. Hafnium implanted in iron 1. Lattice location and annealing behavior

    NARCIS (Netherlands)

    de Bakker, J.M.G.J.; Pleiter, F; Smulders, P.J M

    1993-01-01

    Perturbed angular correlation, Rutherford backscattering and channelling experiments were conducted to study the lattice location and annealing behaviour of 110 keV hafnium ions implanted into iron single crystals. It was found that a fraction of 11-25% of the implanted hafnium atoms are located at

  7. Hafnium implanted in iron 1. Lattice location and annealing behavior

    NARCIS (Netherlands)

    de Bakker, J.M.G.J.; Pleiter, F; Smulders, P.J M

    1993-01-01

    Perturbed angular correlation, Rutherford backscattering and channelling experiments were conducted to study the lattice location and annealing behaviour of 110 keV hafnium ions implanted into iron single crystals. It was found that a fraction of 11-25% of the implanted hafnium atoms are located at

  8. Application of cryopreserved vein grafts as a conduit between the coronary vein and liver graft to reconstruct portal flow in adult living liver transplantation.

    Science.gov (United States)

    Wu, Tsung-Han; Chou, Hong-Shiue; Pan, Kuang-Tse; Lee, Ching-Song; Wu, Ting-Jun; Chu, Sung-Yu; Chen, Miin-Fu; Lee, Wei-Chen

    2009-01-01

    Adult-to-adult living donor liver transplantation is an alternative to donation from a deceased individual, and can help relieve the shortage of liver donations available for adult patients in Asian countries. When transplant candidates have thrombosis and deterioration of the portal vein, living donor liver transplantation is relatively contraindicated because portal veins in the grafts are short and vein grafts may not be available to reconstruct the portal vein. From June 2003 to May 2007, 82 adult living donor liver transplantations were performed at Chang-Gung Memorial Hospital. Three patients had portal vein thrombosis and marked fibrosis of the portal vein and cryopreserved vein grafts were used to reconstruct portal flow from the engorged coronary vein to the graft portal vein. All vein grafts are patent and all patients have normal liver function at 21-36 months after transplantation. When cryopreserved vein grafts are available, adult living donor liver transplantation can be successfully performed in patients with marked deterioration of the portal vein. The short distance from the engorged coronary vein to the graft portal vein may decrease the incidence of re-thrombosis of the venous conduit.

  9. Location and logistics

    OpenAIRE

    Alumura, Sibel A.; Karab, Bahar Y.; Melo, M. Teresa

    2013-01-01

    Facility location decisions play a critical role in designing logistics networks. This article provides some guidelines on how location decisions and logistics functions can be integrated into a single mathematical model to optimize the configuration of a logistics network. This will be illustrated by two generic models, one supporting the design of a forward logistics network and the other addressing the specific requirements of a reverse logistics network. Several special cases and extensio...

  10. Location and logistics

    OpenAIRE

    Alumura, Sibel A.; Karab, Bahar Y.; Melo, M. Teresa

    2013-01-01

    Facility location decisions play a critical role in designing logistics networks. This article provides some guidelines on how location decisions and logistics functions can be integrated into a single mathematical model to optimize the configuration of a logistics network. This will be illustrated by two generic models, one supporting the design of a forward logistics network and the other addressing the specific requirements of a reverse logistics network. Several special cases and extensio...

  11. Calcium-induced patterns of calcium-oxalate crystals in isolated leaflets of Gleditsia triacanthos L. and Albizia julibrissin Durazz.

    Science.gov (United States)

    Borchert, R

    1985-08-01

    For experimental induction of crystal cells (=crystal idioblasts) containing calcium-oxalate crystals, the lower epidermis was peeled from seedling leaflets of Gleditsia triacanthos L., exposing the crystal-free mesophyll and minor veins to the experimental solutions on which leaflets were floated for up to 10 d under continous light. On 0.3-2.0 mM Ca-acetate, increasing numbers of crystals, appearing 96 h after peeling, were induced. The pattern of crystal distribution changed with Ca(2+)-concentration ([Ca(2+)]): at low [Ca(2+)], crystals formed only in the non-green bundlesheath cells surrounding the veins, believed to have a relatively low Ca(2+)-extrusion capacity; at higher [Ca(2+)], crystals developed in up to 90% of the mesophyll cells, and at supraoptimal [Ca(2+)], large extracellular crystals formed on the tissue surface. By sequential treatments with solutions of different [Ca(2+)], the following three phases were identified in the induction of crystal cells: (1) during the initial 24-h period (adaptive aging), Ca(2+) is not required and crystal induction is not possible; (2) during the following 48 h (induction period), exposure to 1-2 mM Ca-acetate induces the differentiation of mesophyll cells into crystal cells; (3) crystal growth begins 72 h after the start of induction. In intact leaflets of Albizia julibrissin Durazz., calcium-oxalate crystals are found exclusively in the bundle-sheath cells of the veins, but crystals were induced in the mesophyll of peeled leaflets floating on 1 mM Ca-acetate. Exposure to inductive [Ca(2+)] will thus trigger the differentiation of mature leaf cells into crystal cells; the spatial distribution of crystals is determined by the external [Ca(2+)] and by the structural and functional properties of the cells in the tissue.

  12. Clinical trials in branch retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Tandava Krishnan Panakanti

    2016-01-01

    Full Text Available Branch retinal vein occlusion (BRVO is the second most common retinal vascular disorder. The management of macular edema has changed considerably over time. The laser is considered the gold standard treatment for over two decades. However, visual recovery with laser is usually slow and incomplete. The advent of intravitreal agents, specifically anti-vascular endothelial growth factors (VEGF have heralded a new era which promises rapid recovery of vision and quality of vision. Randomized clinical trials have reported optimal results with anti-VEGF agents (ranibizumab, bevacizumab, and aflibercept compared to laser therapy or steroids. However, nearly 50% of the patients require repeat intravitreal anti-VEGF therapy up to 4 years after initiating therapy to sustain the visual gains. The adverse events (systemic and ocular of these agents are minimal. Monotherapy with anti-VEGF agents have been found to provide better results than any combination with laser. This review article summarizes evidence from randomized controlled trials evaluating treatment options for the treatment of macular edema secondary to BRVO with a special focus on anti-VEGF therapy.

  13. Deep Vein Thrombosis Prophylaxis in Trauma Patients

    Directory of Open Access Journals (Sweden)

    Serdar Toker

    2011-01-01

    Full Text Available Deep vein thrombosis (DVT and pulmonary embolism (PE are known collectively as venous thromboembolism (VTE. Venous thromboembolic events are common and potentially life-threatening complications following trauma with an incidence of\t5 to 63%. DVT prophylaxis is essential in the management of trauma patients. Currently, the optimal VTE prophylaxis strategy for trauma patients is unknown. Traditionally, pelvic and lower extremity fractures, head injury, and prolonged immobilization have been considered risk factors for VTE; however it is unclear which combination of risk factors defines a high-risk group. Modalities available for trauma patient thromboprophylaxis are classified into pharmacologic anticoagulation, mechanical prophylaxis, and inferior vena cava (IVC filters. The available pharmacologic agents include low-dose heparin (LDH, low molecular weight heparin (LMWH, and factor Xa inhibitors. Mechanical prophylaxis methods include graduated compression stockings (GCSs, pneumatic compression devices (PCDs, and A-V foot pumps. IVCs are traditionally used in high risk patients in whom pharmacological prophylaxis is contraindicated. Both EAST and ACCP guidelines recommend primary use of LMWHs in trauma patients; however there are still controversies regarding the definitive VTE prophylaxis in trauma patients. Large randomized prospective clinical studies would be required to provide level I evidence to define the optimal VTE prophylaxis in trauma patients.

  14. Clinical Trials in Branch Retinal Vein Occlusion

    Science.gov (United States)

    Panakanti, Tandava Krishnan; Chhablani, Jay

    2016-01-01

    Branch retinal vein occlusion (BRVO) is the second most common retinal vascular disorder. The management of macular edema has changed considerably over time. The laser is considered the gold standard treatment for over two decades. However, visual recovery with laser is usually slow and incomplete. The advent of intravitreal agents, specifically anti-vascular endothelial growth factors (VEGF) have heralded a new era which promises rapid recovery of vision and quality of vision. Randomized clinical trials have reported optimal results with anti-VEGF agents (ranibizumab, bevacizumab, and aflibercept) compared to laser therapy or steroids. However, nearly 50% of the patients require repeat intravitreal anti-VEGF therapy up to 4 years after initiating therapy to sustain the visual gains. The adverse events (systemic and ocular) of these agents are minimal. Monotherapy with anti-VEGF agents have been found to provide better results than any combination with laser. This review article summarizes evidence from randomized controlled trials evaluating treatment options for the treatment of macular edema secondary to BRVO with a special focus on anti-VEGF therapy. PMID:26957837

  15. Portal vein embolization for hepatocellular carcinoma.

    Science.gov (United States)

    Shindoh, Junichi; D Tzeng, Ching-Wei; Vauthey, Jean-Nicolas

    2012-11-01

    Portal vein embolization (PVE) improves the safety of major hepatectomy through hypertrophy of the future liver remnant (FLR), atrophy of the liver volume to be resected, and improvement in patient selection. Because most patients with hepatocellular carcinoma (HCC) have liver parenchymal injury due to underlying viral hepatitis or alcoholic liver fibrosis/cirrhosis, indication of PVE is relatively complex and sequential procedures, including transarterial chemoembolization, are required to maximize the effect of PVE as well as to minimize tumor progression due to increased arterial flow after PVE. PVE is currently indicated for patients with relatively well-preserved hepatic function [Child-Pugh A and indocyanine green tolerance test (ICG-R15) 40% is the minimal requirement for patients with chronic hepatitis or cirrhosis, and further strict criteria (FLR volume >50%) have been recommended for patients with marginal liver functional reserve (ICG-R15, 10-20%). Recent clinical results have suggested that PVE can be safely performed in patients with HCC and that it contributes to improved survival after major hepatectomy.

  16. Deep vein thrombosis prophylaxis in trauma patients.

    Science.gov (United States)

    Toker, Serdar; Hak, David J; Morgan, Steven J

    2011-01-01

    Deep vein thrombosis (DVT) and pulmonary embolism (PE) are known collectively as venous thromboembolism (VTE). Venous thromboembolic events are common and potentially life-threatening complications following trauma with an incidence of 5 to 63%. DVT prophylaxis is essential in the management of trauma patients. Currently, the optimal VTE prophylaxis strategy for trauma patients is unknown. Traditionally, pelvic and lower extremity fractures, head injury, and prolonged immobilization have been considered risk factors for VTE; however it is unclear which combination of risk factors defines a high-risk group. Modalities available for trauma patient thromboprophylaxis are classified into pharmacologic anticoagulation, mechanical prophylaxis, and inferior vena cava (IVC) filters. The available pharmacologic agents include low-dose heparin (LDH), low molecular weight heparin (LMWH), and factor Xa inhibitors. Mechanical prophylaxis methods include graduated compression stockings (GCSs), pneumatic compression devices (PCDs), and A-V foot pumps. IVCs are traditionally used in high risk patients in whom pharmacological prophylaxis is contraindicated. Both EAST and ACCP guidelines recommend primary use of LMWHs in trauma patients; however there are still controversies regarding the definitive VTE prophylaxis in trauma patients. Large randomized prospective clinical studies would be required to provide level I evidence to define the optimal VTE prophylaxis in trauma patients.

  17. Nitroprusside modulates pulmonary vein arrhythmogenic activity

    Directory of Open Access Journals (Sweden)

    Chen Yao-Chang

    2010-03-01

    Full Text Available Abstract Background Pulmonary veins (PVs are the most important sources of ectopic beats with the initiation of paroxysmal atrial fibrillation, or the foci of ectopic atrial tachycardia and focal atrial fibrillation. Elimination of nitric oxide (NO enhances cardiac triggered activity, and NO can decrease PV arrhythmogensis through mechano-electrical feedback. However, it is not clear whether NO may have direct electrophysiological effects on PV cardiomyocytes. This study is aimed to study the effects of nitroprusside (NO donor, on the ionic currents and arrhythmogenic activity of single cardiomyocytes from the PVs. Methods Single PV cardiomyocytes were isolated from the canine PVs. The action potential and ionic currents were investigated in isolated single canine PV cardiomyocytes before and after sodium nitroprusside (80 μM, using the whole-cell patch clamp technique. Results Nitroprusside decreased PV cardiomyocytes spontaneous beating rates from 1.7 ± 0.3 Hz to 0.5 ± 0.4 Hz in 9 cells (P Conclusion Nitroprusside regulates the electrical activity of PV cardiomyocytes, which suggests that NO may play a role in PV arrhythmogenesis.

  18. Fundus changes in central retinal vein occlusion.

    Science.gov (United States)

    Hayreh, Sohan Singh; Zimmerman, M Bridget

    2015-01-01

    To investigate systematically the retinal and optic disk changes in central retinal vein occlusion (CRVO) and their natural history. This study comprised 562 consecutive patients with CRVO (492 nonischemic [NI-CRVO] and 89 ischemic CRVO [I-CRVO] eyes) seen within 3 months of onset. Ophthalmic evaluation at initial and follow-up visits included recording visual acuity, visual fields, and detailed anterior segment and fundus examinations and fluorescein fundus angiography. Retinal and subinternal limiting membrane hemorrhages and optic disk edema in I-CRVO were initially more marked (P retinal epithelial pigment degeneration, serous macular detachment, and retinal perivenous sheathing developed at a higher rate in I-CRVO than that in NI-CRVO (P retinal venous engorgement than NI-CRVO (P = 0.003). Fluorescein fundus angiography showed significantly more fluorescein leakage, retinal capillary dilatation, capillary obliteration, and broken capillary foveal arcade (P < 0.0001) in I-CRVO than NI-CRVO. Resolution time of CRVO was longer for I-CRVO than NI-CRVO (P < 0.0001). Characteristics and natural history of fundus findings in the two types of CRVO are different.

  19. Anomalous azygos veins - its embryological basis and clinical significance

    Directory of Open Access Journals (Sweden)

    Uma Shivanal

    2015-09-01

    Results: In the present study, normal azygos venous system was found in 8 specimens accounting for 80%. Variations were found in 2 specimens (20%; one specimen presented with connection between accessory hemiazygos vein and hemiazygos vein, 3 transverse channels across vertebral column and the other specimen showed absence of accessory hemiazygos vein and shifting of azygos vein towards midline. Conclusions: Accurate knowledge about these kinds of variations is very important to identify, especially in the computed tomography and magnetic resonance imaging of mediastinum. The abnormal azygos venous system may easily be confused with aneurysm, lymphadenopathy and other abnormalities like tumor. It is important to keep these kinds of variations in mind while performing the mediastinal operations or surgery of large vessels. [Int J Res Med Sci 2015; 3(9.000: 2323-2326

  20. Plantar vein thrombosis: a rare cause of plantar foot pain

    Energy Technology Data Exchange (ETDEWEB)

    Siegal, Daniel S.; Wu, Jim S.; Brennan, Darren D.; Hochman, Mary G. [Beth Israel Deaconess Medical Center, Department of Radiology, Boston, MA (United States); Challies, Tracy [Beth Israel Deaconess Medical Center, Department of Pathology, Boston, MA (United States)

    2008-03-15

    Plantar vein thrombosis is a rare condition, with only a handful of cases reported in the literature. The cause is unknown; however, the disease has been attributed to prior surgery, trauma, and paraneoplastic conditions. We present a case of a 32-year-old female runner with plantar vein thrombosis diagnosed on contrast-enhanced MRI and confirmed on ultrasound. The symptoms resolved with conservative treatment and evaluation revealed the presence of a prothrombin gene mutation and use of oral contraceptive pills. To our knowledge, this is the first case of plantar vein thrombosis diagnosed initially by MRI. Moreover, this case suggests that plantar vein thrombosis should be considered in patients with hypercoagulable states and plantar foot pain. (orig.)

  1. Central Retinal Vein Occlusion AssociatedWith Sildenafil (Viagra

    Directory of Open Access Journals (Sweden)

    H C Obiudu

    2010-01-01

    Conclusion - Central retinal vein occlusion is a possible adverse effect of sildenafil use. Physicians should be vigilant while prescribing thismedication and avoid its use in patients with elevated intraocular pressure

  2. Personal authentication using hand vein triangulation and knuckle shape.

    Science.gov (United States)

    Kumar, Ajay; Prathyusha, K Venkata

    2009-09-01

    This paper presents a new approach to authenticate individuals using triangulation of hand vein images and simultaneous extraction of knuckle shape information. The proposed method is fully automated and employs palm dorsal hand vein images acquired from the low-cost, near infrared, contactless imaging. The knuckle tips are used as key points for the image normalization and extraction of region of interest. The matching scores are generated in two parallel stages: (i) hierarchical matching score from the four topologies of triangulation in the binarized vein structures and (ii) from the geometrical features consisting of knuckle point perimeter distances in the acquired images. The weighted score level combination from these two matching scores are used to authenticate the individuals. The achieved experimental results from the proposed system using contactless palm dorsal-hand vein images are promising (equal error rate of 1.14%) and suggest more user friendly alternative for user identification.

  3. HIV associated deep vein thrombosis: Case reports from Jos, Nigeria

    Directory of Open Access Journals (Sweden)

    C A Daniyam

    2011-01-01

    Full Text Available Deep vein thrombosis (DVT has been reported to be 2-10 times commoner in HIV infected patients than in the general population. We report two cases of extensive unilateral deep vein thrombosis involving the lower limb in HIV infected patients on highly active antiretroviral therapy (HAART. Doppler ultrasound in the two patients revealed evidence of venous thrombosis from the femoral vein down to the posterior tibial veins. None of the patients had a history of acquired risk factors for DVT. Both patients responded well to anti-coagulants. A high index of suspicion may therefore be required to make the diagnosis and institute adequate management for this condition which has potentially life threatening consequences.

  4. Management Strategy for Patients With Chronic Subclavian Vein Thrombosis.

    Science.gov (United States)

    Keir, Graham; Marshall, M Blair

    2017-02-01

    We performed a systematic review to determine best practice for the management of patients with chronic or subacute subclavian vein thrombosis. This condition is best managed with surgical excision of the first rib followed by long-term anticoagulation. Interventional techniques aimed at restoring patency are ineffective beyond 2 weeks postthrombosis. Additional therapeutic options should be made based on the severity of symptoms as well as vein status. Patients with milder symptoms are given decompression surgery followed by anticoagulation whereas patients with more severe symptoms are considered for either a jugular vein transposition or saphenous patch based on the vein characteristics. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  5. TIPS performed in a patient with complete portal vein thrombosis

    Directory of Open Access Journals (Sweden)

    Ashwani Kumar Sharma, MD

    2017-06-01

    Full Text Available Portal vein thrombosis is common in cirrhotic patients and results in increased morbidity and mortality. Transjugular intrahepatic portosystemic shunt (TIPS creation is a well-established therapy for refractory variceal bleeding and refractory ascites in patients who do not tolerate repeated large volume paracentesis. Experience and technical improvements have led to improved TIPS outcomes that have encouraged an expanded application. Complete portal vein thrombosis has come a long way from being a contraindication to an indication for TIPS procedure. As experience and technology have evolved, the ultrasound guidance transvenous access of portal vein from the hepatic vein help in overall higher success rate of performing the TIPS procedure and reducing the procedure-related complications.

  6. Ovarian vein thrombosis in Behçet disease.

    Science.gov (United States)

    Tan, Justina Wei Lynn; Howe, Hwee Siew; Chng, Hiok Hee

    2012-03-01

    We describe a 35-year-old Chinese woman with Behçet disease complicated by recurrent gastrointestinal flares. During admission for acute lower abdominal pain, a computed tomographic scan of the abdomen showed thrombosis of the left ovarian vein. She was treated with increased immunosuppressant and oral anticoagulant. Although she was not compliant to oral anticoagulant with her international normalized ratio frequently subtherapeutic, her symptoms abated and the thrombosis resolved. There has been only 1 reported case of a patient with Behçet disease presenting with postpartum ovarian vein thrombosis and pulmonary embolism and no reported case of Behçet disease with ovarian vein thrombosis occurring outside pregnancy and the puerperium. Ovarian vein thrombosis is a rare cause of abdominal pain that should be considered in patients with Behçet disease.

  7. Anti-GBM disease and renal vein thrombosis.

    Science.gov (United States)

    Bailey, Phillippa; Sarfraz, Farook; Ravanan, Rommel

    2011-11-15

    A 23-year-old female who presented with advanced renal failure was subsequently diagnosed with renal vein thrombosis and antiglomerular basement membrane (GBM) antibody disease. A previous case of renal vein thrombosis has been reported in association with anti-GBM disease, but to our knowledge, this is the first reported case in which the presentation of anti-GBM disease and renal vein thrombosis was concurrent. Further study is essential to understand if the association of anti-GBM disease and renal vein thrombosis as seen in our case was pure coincidence or is in fact occurs more frequently. It may be that the dual diagnosis is not made as establishing one sufficient diagnosis for renal failure may halt further investigations for additional diagnoses.

  8. Infrahepatic inferior vena cava agenesis with bilateral renal vein thrombosis.

    Science.gov (United States)

    Skeik, Nedaa; Wickstrom, Kelly K; Schumacher, Clark W; Sullivan, Timothy M

    2013-10-01

    Congenital anomalies of the inferior vena cava (IVC) are rare and are estimated to be present in 0.07-8.7% of the general population. IVC agenesis (IVCA) is found in approximately 5% of cases of unprovoked lower extremity deep vein thrombosis in patients Renal vein thrombosis (RVT) is an extremely rare and unusual presentation of IVCA. We report a unique case of a 23-year-old previously healthy man presenting with infrahepatic IVCA-induced bilateral RVT with azygos and hemiazygos continuation. To our knowledge, this is the third reported case in the literature of IVCA-induced RVT and the first to affect the bilateral renal veins in the absence of any other thrombogenic risk factors or any lower extremity venous complications. We also present a literature review of IVCA-induced vein thrombosis and highlight the lack of literature to manage this condition.

  9. Acute scrotal pain: an uncommon manifestation of renal vein thrombosis.

    Science.gov (United States)

    Jou, Yeong-Chin; Jong, Ing-Chin; Hsieh, Ying-Chen; Kang, Chun-Hsiung

    2014-03-01

    The clinical manifestation of renal vein thrombosis varies with the speed and degree of venous occlusion. Such patients may be asymptomatic, have minor nonspecific symptoms such as nausea or weakness, or have more specific symptoms such as upper abdominal pain, flank pain, or hematuria. Acute scrotal pain is a very uncommon clinical expression of renal vein thrombosis. Here, we report a case of membranous glomerulonephritis-induced renal vein thrombosis presented with the symptom of acute scrotal pain caused by thrombosis-induced varicocele. This case report suggests that renal vein thrombosis should be considered in the diagnosis of acute scrotal pain; it also emphasizes that an investigation of retroperitoneum should be performed for adult patients with the sudden onset of varicocele.

  10. A study of dorsal vein pattern for biometric security

    African Journals Online (AJOL)

    Nafiisah

    A biometric system can function in any of these two modes; verification mode or ..... Then the Gaussian blur filter is applied to filter noise. ... edge weighted diffusion was applied to smoothen the image while preserving the vein edges. [3].

  11. Method to Quantify Tail Vein Injection Technique in Small Animals

    National Research Council Canada - National Science Library

    Groman, Ernest V; Reinhardt, Christopher P

    2004-01-01

    .... In this report, we propose six criteria for a reagent designed to assess tail vein injection technique in small animals and suggest a reagent, colloidal gold labeled with the stable isotope 197Au...

  12. Dorsal Hand Vein Biometry by Independent Component Analysis

    Directory of Open Access Journals (Sweden)

    V.H.Yadav

    2012-07-01

    Full Text Available Biometric authentication provides a high security and reliable approach to be used in security access system. Personal identification based on hand vein patterns is a newly developed recent year. The pattern of blood veins in the hand is unique to every individual, even among identical twins, and it do notchange over time. These properties of uniqueness, stability and strong immunity to forgery of the vein patterns make it a potentially good biometric trait which offers greater security and reliable features for personal identification. In this study, we have used the BOSPHORUS hand vein database which has been taken under a source of NIR infrared radiation. For feature extraction we applied appearance based method ICA which produces independent components. To control over the number of independent component we preprocessed data by PCA before applying ICA, and gives good experimental results.

  13. Sectional localization of a small hepatocellular carcinoma in the right hepatic lobe by computed tomography: Comparison between the conventional and portal vein tracing methods

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Chun-Gao [Seoul National University Hospital, Department of Radiology, Jongro-gu, Seoul (Korea, Republic of); The First Affiliated Hospital of Nanjing Medical University, Department of Interventional Radiology, Nanjing (China); Chung, Jin Wook; Hur, Saebeom; Lee, Myungsu; Kim, Hyo-Cheol; Jae, Hwan Jun; Yin, Yong-Hu; Kim, Young Il [Seoul National University Hospital, Department of Radiology, Jongro-gu, Seoul (Korea, Republic of); Ahn, Sang-bu [Dongnam Institution of Radiological and Medical Sciences, Department of Radiology, Busan (Korea, Republic of); Cho, Baik Hwan [Chonbuk National University Hospital, Department of Radiology, Jeonju (Korea, Republic of)

    2016-12-15

    To compare the accuracy of the conventional and portal vein tracing methods in the right hepatic lobe in multidetector computed tomography (MDCT). This retrospective study included patients with hepatocellular carcinoma (HCC) lesions in the right hepatic lobe who underwent multiphasic MDCT and C-arm CT hepatic arteriography (C-arm CTHA) for chemoembolization. The accuracies of the conventional and portal vein tracing methods were evaluated using C-arm CTHA as the gold standard. A total of 147 patients with 205 HCC nodules were included. The C-arm CTHA could identify all the tumour-feeding arteries and consequently demonstrated that 120 lesions were located in the anterior section, 78 in the posterior section, and 7 in the border zone. The accuracy rates of conventional vs. portal vein tracing methods were 71.7 % vs. 98.3 % for the anterior section lesions, 67.9 % vs. 96.2 % for the posterior section, and 28.6 % vs. 57.1 % for the border zone. The portal vein tracing method was more accurate than the conventional method (P<0.001). The portal vein tracing method should be used for sectional localization of HCCs in the right lobe, because it predicts the location more accurately than the conventional method. (orig.)

  14. Ultrasonography of the lower extremity veins: Anatomy and basic approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Kyu; Ahn, Kyung Sik; Kang, Chang Ho; Cho, Sung Bum [Dept. of Radiology, Korea University Anam Hospital, Korea University College of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Ultrasonography is an imaging modality widely used to evaluate venous diseases of the lower extremities. It is important to understand the normal venous anatomy of the lower extremities, which has deep, superficial, and perforating venous components, in order to determine the pathophysiology of venous disease. This review provides a basic description of the anatomy of the lower extremity veins and useful techniques for approaching each vein via ultrasonography.

  15. Chylous ascites caused by acute pancreatitis with portal vein thrombosis

    OpenAIRE

    Park, Dong Eun; Chae, Kwon Mook

    2011-01-01

    Chylous ascites is defined as the accumulation of chyle in the peritoneum due to obstruction or rupture of the peritoneal or retroperitoneal lymphatic glands. Chylous ascites that arises from acute pancreatitis with portal vein thrombosis is very rare. We report here on a case of chylous ascite that was caused by acute pancreatitis with portal vein thrombosis, in which the patient showed an impressive response to conservative therapy with total parenteral nutrition and octerotide. We also rev...

  16. Sciatica caused by a dilated epidural vein: MR findings

    Energy Technology Data Exchange (ETDEWEB)

    Demaerel, P.; Petre, C.; Wilms, G. [Dept. of Radiology, Catholic University of Leuven (Belgium); Plets, C. [Dept. of Neurosurgery, Catholic University of Leuven (Belgium)

    1999-02-01

    We report the MR imaging findings in a 41-year-old woman presenting with sudden low back pain and sciatica. At surgery a dilated epidural vein was found compressing the nerve root. The MR findings may suggest the diagnosis. Magnetic resonance imaging of a dilated epidural vein or varix causing sciatica has not been reported until now. (orig.) (orig.) With 1 fig., 4 refs.

  17. Plantar Vein Thrombosis: An Unusual Cause of Plantar Pain

    OpenAIRE

    Vansevenant, Milan; Vanhoenacker, Filip M.

    2015-01-01

    We present a case of an 80-year-old man with progressive pain for 5 days at the medial and plantar aspect of the left heel. Wearing shoes aggravated the pain. Ultrasound and magnetic resonance imaging (MRI) revealed thrombosis of the medial plantar veins. Plantar vein thrombosis is a rare condition. The clinical symptoms are non-specific and can be confused with plantar fasciitis. It has been associated with hypercoagulable conditions, foot trauma and recent surgery. The imaging modality of c...

  18. Sheathotomy in complicated cases of branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Crafoord, S.; Karlsson, N.; Cour, M. la

    2008-01-01

    Purpose: To report the clinical experience and results of using a microsurgical technique to decompress the arteriovenous connection in complicated branch retinal vein occlusion (BRVO) combined with haemorrhage, oedema an ischaemia. Methods: We carried out a retrospective, non-randomized, interve......Purpose: To report the clinical experience and results of using a microsurgical technique to decompress the arteriovenous connection in complicated branch retinal vein occlusion (BRVO) combined with haemorrhage, oedema an ischaemia. Methods: We carried out a retrospective, non...

  19. Ovarian Vein Thrombosis as a Complication of Laparoscopic Surgery

    OpenAIRE

    Anu Gupta; Natasha Gupta; Josef Blankstein; Richard Trester

    2015-01-01

    Ovarian vein thrombosis (OVT) is an extremely rare but life-threatening complication of the postpartum period. It has never been reported as a complication of laparoscopic surgery. We report a case of right ovarian vein thrombosis that occurred in the postoperative period after patient underwent laparoscopic salpingectomy for a right side ectopic pregnancy. She presented with 1-week history of abdominal pain and fever. A complete workup for fever was performed and was found negative. Computed...

  20. Clinical Features of Primary Vein Grafts in Free Tissue Transfers

    OpenAIRE

    Mitsuru Nemoto; Kenichi Kumazawa; Eiju Uchinuma; Natsuko Kounoike; Akira Takeda

    2015-01-01

    The outcomes of free tissue transfers combined with vein grafts have been inconsistent, and discussions continue regarding their appropriate use. Of the 142 free tissue transfers that we performed from January 2004 to December 2011, we retrospectively analyzed 15 consecutive patients who underwent free tissue transfers in combination with vein grafts. Etiologies included trauma (8 patients), infection (4), and tumor (3). Types of free tissue transfers were fibula (4), anterolateral thigh (3),...

  1. Branch retinal vein occlusion associated with quetiapine fumarate

    Directory of Open Access Journals (Sweden)

    Siang Lim

    2011-08-01

    Full Text Available Abstract Background To report a case of branch retinal vein occlusion in a young adult with bipolar mood disorder treated with quetiapine fumarate. Case Presentation A 29 years old gentleman who was taking quetiapine fumarate for 3 years for bipolar mood disorder, presented with sudden vision loss. He was found to have a superior temporal branch retinal vein occlusion associated with hypercholesterolemia. Conclusion Atypical antipsychotic drugs have metabolic side effects which require regular monitoring and prompt treatment.

  2. Finger Vein Segmentation from Infrared Images Based on a Modified Separable Mumford Shah Model and Local Entropy Thresholding

    Directory of Open Access Journals (Sweden)

    Marios Vlachos

    2015-01-01

    Full Text Available A novel method for finger vein pattern extraction from infrared images is presented. This method involves four steps: preprocessing which performs local normalization of the image intensity, image enhancement, image segmentation, and finally postprocessing for image cleaning. In the image enhancement step, an image which will be both smooth and similar to the original is sought. The enhanced image is obtained by minimizing the objective function of a modified separable Mumford Shah Model. Since, this minimization procedure is computationally intensive for large images, a local application of the Mumford Shah Model in small window neighborhoods is proposed. The finger veins are located in concave nonsmooth regions and, so, in order to distinct them from the other tissue parts, all the differences between the smooth neighborhoods, obtained by the local application of the model, and the corresponding windows of the original image are added. After that, veins in the enhanced image have been sufficiently emphasized. Thus, after image enhancement, an accurate segmentation can be obtained readily by a local entropy thresholding method. Finally, the resulted binary image may suffer from some misclassifications and, so, a postprocessing step is performed in order to extract a robust finger vein pattern.

  3. Finger Vein Segmentation from Infrared Images Based on a Modified Separable Mumford Shah Model and Local Entropy Thresholding.

    Science.gov (United States)

    Vlachos, Marios; Dermatas, Evangelos

    2015-01-01

    A novel method for finger vein pattern extraction from infrared images is presented. This method involves four steps: preprocessing which performs local normalization of the image intensity, image enhancement, image segmentation, and finally postprocessing for image cleaning. In the image enhancement step, an image which will be both smooth and similar to the original is sought. The enhanced image is obtained by minimizing the objective function of a modified separable Mumford Shah Model. Since, this minimization procedure is computationally intensive for large images, a local application of the Mumford Shah Model in small window neighborhoods is proposed. The finger veins are located in concave nonsmooth regions and, so, in order to distinct them from the other tissue parts, all the differences between the smooth neighborhoods, obtained by the local application of the model, and the corresponding windows of the original image are added. After that, veins in the enhanced image have been sufficiently emphasized. Thus, after image enhancement, an accurate segmentation can be obtained readily by a local entropy thresholding method. Finally, the resulted binary image may suffer from some misclassifications and, so, a postprocessing step is performed in order to extract a robust finger vein pattern.

  4. Prognosis of Hepatocellular Carcinoma with Portal Vein Tumor Thrombus:Assessment Based on Clinical and Computer Tomography Characteristics

    Directory of Open Access Journals (Sweden)

    Jia,Lizhong

    2012-04-01

    Full Text Available Patients with hepatocellular carcinoma (HCC complicated by portal vein tumor thrombus (PVTT have an extremely poor prognosis. It is important to select adequate therapeutic options based on reliable prognostic factors using imaging studies and clinical data. Prognostic factors were analyzed in patients with HCC with PVTT in the first branch or main trunk of the portal vein. From 2000 to 2007, 107 consecutive patients with HCC with PVTT in the major portal vein were reviewed, and diagnostic images and clinical characteristics were retrospectively observed. Thirty-eight possible prognostic factors for survival were analyzed by the log-rank test and multivariate analysis using Coxʼs proportional hazards model. Median overall survival was 14 months following PVTT diagnosis. Survival rates at 6 months, 1, 2, and 3 years were 72.1%, 52.6%, 32.6%, and 29.6%, respectively. Independent prognostic factors for longer survival included:patient age <65 years, Child-Pugh classification A/B, PVTT treatment, accumulation of Lipiodol in the PVTT after TACE, initial radical treatment for HCC, HCC located in a single lobe of the liver, and no invasion of HCC to the hepatic vein or bile duct. Survival was associated with liver function, tumor extension, and treatment for HCC and PVTT.

  5. Polyphase vein mineralization in the Fennoscandian Shield at Åkerlandet, Järvsand, and Laisvall along the erosional front of the Caledonian orogen, Sweden

    Science.gov (United States)

    Saintilan, Nicolas J.; Stephens, Michael B.; Spikings, Richard; Schneider, Jens; Chiaradia, Massimo; Spangenberg, Jorge E.; Ulianov, Alexey; Fontboté, Lluís

    2016-12-01

    The Åkerlandet, Järvsand, and Laisvall deposits in Sweden are calcite-fluorite-sulfide vein deposits and occurrences located close to the current erosional front of the Caledonian orogen and hosted by crystalline basement rocks in the Fennoscandian Shield. At Laisvall, basement-hosted veinlets occur beneath Ediacaran to Cambrian sandstones that host a strata-bound Pb-Zn deposit. The mineralized fractures at Åkerlandet and Järvsand occur along fault systems oriented N-S to NNW-SSE. Veins or veinlets strike NNW-SSE and NW-SE at Åkerlandet, NNE-SSW at Järvsand, and NNW-SSE and NNE-SSW to NE-SW at Laisvall. At Åkerlandet and Järvsand, fractures acted as conduits for hydrothermal fluids of variable composition and formed during separate tectonic events. At Åkerlandet, the fault zone with NNW-SSE strike shows kinematic indicators consistent with NE-SW bulk horizontal extension. At Järvsand, the calcite-fluorite-galena veins formed along R-Riedel shears related to the host N-S to NNW-SSE fault system. The kinematic indicators are consistent with NW-SE bulk horizontal extension, similar to the extensional deformation during the later part of the Caledonian orogeny (Silurian to Devonian). At Åkerlandet, adularia-quartz deposition was followed by sphalerite ± galena and finally by precipitation of fluorite and calcite. 40Ar-39Ar thermochronology of a single adularia sample did not yield a well-defined plateau age but the gas released at higher temperatures suggests an early Tonian (980 to 950 Ma) crystallization age, i.e., during the later part of the Sveconorwegian orogeny, although the data do not exclude other less likely interpretations. Previous fluid inclusion microthermometry and geochronological studies and new petrographic and geochemical results suggest that sphalerite ± galena mineralization formed from saline, relatively oxidizing, moderate-temperature, and slightly acidic hydrothermal fluids, either during the Ediacaran or the Middle Ordovician

  6. The mechanics of intersecting echelon veins and pressure solution seams in limestone

    Science.gov (United States)

    Seyum, Solomon; Pollard, David D.

    2016-08-01

    Many studies that describe the formation of echelon vein arrays relate the causative stresses implicitly to the deformation, reliant on simple shear kinematics, such that the vein-to-array angle and the array width are the primary physical quantities. In contrast, we identify twelve physical quantities to describe echelon veins in two dimensions, including coeval, vein-intersecting, pressure solution seams. A finite element method is used to reproduce vein shapes in linear elastic and elastic-perfectly plastic model limestone. Model vein geometries are designed using values within the range of geometries measured from echelon veins at Raplee Anticline and Comb Monocline, Utah. Four physical quantities are significant for describing echelon vein shapes: vein spacing, vein-array angle, limestone elastic stiffness, and closing of orthogonal pressure solution seams. Pressure solution seam closing influences the mechanical interaction between adjacent veins, and for a range of conditions, causes a nearly linear vein opening distribution (triangular shapes) and encourages straight vein propagation, both of which approximate field measurements. Model results show that small spacing of veins with seams and large vein-array angles promote straight vein traces in limestone with stiffness typical of laboratory measurements, given the physical geologic conditions inferred from the burial history of the limestone strata.

  7. Towards an integrated numerical simulator for crack-seal vein microstructure: Coupling phase-field with the Discrete Element Method

    Science.gov (United States)

    Virgo, Simon; Ankit, Kumar; Nestler, Britta; Urai, Janos L.

    2016-04-01

    Crack-seal veins form in a complex interplay of coupled thermal, hydraulic, mechanical and chemical processes. Their formation and cyclic growth involves brittle fracturing and dilatancy, phases of increased fluid flow and the growth of crystals that fill the voids and reestablish the mechanical strength. Existing numerical models of vein formation focus on selected aspects of the coupled process. Until today, no model exists that is able to use a realistic representation of the fracturing AND sealing processes, simultaneously. To address this challenge, we propose the bidirectional coupling of two numerical methods that have proven themselves as very powerful to model the fundamental processes acting in crack-seal systems: Phase-field and the Discrete Element Method (DEM). The phase-field Method was recently successfully extended to model the precipitation of quartz crystals from an aqueous solution and applied to model the sealing of a vein over multiple opening events (Ankit et al., 2013; Ankit et al., 2015a; Ankit et al., 2015b). The advantage over former, purely kinematic approaches is that in phase-field, the crystal growth is modeled based on thermodynamic and kinetic principles. Different driving forces for microstructure evolution, such as chemical bulk free energy, interfacial energy, elastic strain energy and different transport processes, such as mass diffusion and advection, can be coupled and the effect on the evolution process can be studied in 3D. The Discrete Element Method was already used in several studies to model the fracturing of rocks and the incremental growth of veins by repeated fracturing (Virgo et al., 2013; Virgo et al., 2014). Materials in DEM are represented by volumes of packed spherical particles and the response to the material to stress is modeled by interaction of the particles with their nearest neighbours. For rocks, in 3D, the method provides a realistic brittle failure behaviour. Exchange Routines are being developed that

  8. Geostar - Navigation location system

    Science.gov (United States)

    Keyser, Donald A.

    The author describes the Radiodetermination Satellite Service (RDSS). The initial phase of the RDSS provides for a unique service enabling central offices and headquarters to obtain position-location information and receive short digital messages from mobile user terminals throughout the contiguous United States, southern Canada, and northern Mexico. The system employs a spread-spectrum, CDMA modulation technique allowing multiple customers to use the system simultaneously, without preassigned coordination with fellow users. Position location is currently determined by employing an existing radio determination receiver, such as Loran-C, GPS, or Transit, in the mobile user terminal. In the early 1990s position location will be determined at a central earth station by time-differential ranging of the user terminals via two or more geostationary satellites. A brief overview of the RDSS system architecture is presented with emphasis on the user terminal and its diverse applications.

  9. Vein graft adaptation and fistula maturation in the arterial environment

    Science.gov (United States)

    Lu, Daniel Y; Chen, Elizabeth Y; Wong, Daniel J; Yamamoto, Kota; Protack, Clinton D; Williams, Willis T; Assi, Roland; Hall, Michael R; Sadaghianloo, Nirvana; Dardik, Alan

    2014-01-01

    Veins are exposed to the arterial environment during two common surgical procedures, creation of vein grafts and arteriovenous fistulae (AVF). In both cases veins adapt to the arterial environment that is characterized by different hemodynamic conditions and increased oxygen tension compared to the venous environment. Successful venous adaptation to the arterial environment is critical for long term success of the vein graft or AVF, and in both cases is generally characterized by venous dilation and wall thickening. However, AVF are exposed to a high flow, high shear stress, low pressure arterial environment, and adapt mainly via outward dilation with less intimal thickening. Vein grafts are exposed to a moderate flow, moderate shear stress, high pressure arterial environment, and adapt mainly via increased wall thickening with less outward dilation. We review the data that describe these differences, as well as the underlying molecular mechanisms that mediate these processes. Despite extensive research, there are few differences in the molecular pathways that regulate cell proliferation and migration or matrix synthesis, secretion, or degradation currently identified between vein graft adaptation and AVF maturation that account for the different types of venous adaptation to arterial environments. PMID:24582063

  10. Robust finger vein ROI localization based on flexible segmentation.

    Science.gov (United States)

    Lu, Yu; Xie, Shan Juan; Yoon, Sook; Yang, Jucheng; Park, Dong Sun

    2013-10-24

    Finger veins have been proved to be an effective biometric for personal identification in the recent years. However, finger vein images are easily affected by influences such as image translation, orientation, scale, scattering, finger structure, complicated background, uneven illumination, and collection posture. All these factors may contribute to inaccurate region of interest (ROI) definition, and so degrade the performance of finger vein identification system. To improve this problem, in this paper, we propose a finger vein ROI localization method that has high effectiveness and robustness against the above factors. The proposed method consists of a set of steps to localize ROIs accurately, namely segmentation, orientation correction, and ROI detection. Accurate finger region segmentation and correct calculated orientation can support each other to produce higher accuracy in localizing ROIs. Extensive experiments have been performed on the finger vein image database, MMCBNU_6000, to verify the robustness of the proposed method. The proposed method shows the segmentation accuracy of 100%. Furthermore, the average processing time of the proposed method is 22 ms for an acquired image, which satisfies the criterion of a real-time finger vein identification system.

  11. Robust Finger Vein ROI Localization Based on Flexible Segmentation

    Directory of Open Access Journals (Sweden)

    Dong Sun Park

    2013-10-01

    Full Text Available Finger veins have been proved to be an effective biometric for personal identification in the recent years. However, finger vein images are easily affected by influences such as image translation, orientation, scale, scattering, finger structure, complicated background, uneven illumination, and collection posture. All these factors may contribute to inaccurate region of interest (ROI definition, and so degrade the performance of finger vein identification system. To improve this problem, in this paper, we propose a finger vein ROI localization method that has high effectiveness and robustness against the above factors. The proposed method consists of a set of steps to localize ROIs accurately, namely segmentation, orientation correction, and ROI detection. Accurate finger region segmentation and correct calculated orientation can support each other to produce higher accuracy in localizing ROIs. Extensive experiments have been performed on the finger vein image database, MMCBNU_6000, to verify the robustness of the proposed method. The proposed method shows the segmentation accuracy of 100%. Furthermore, the average processing time of the proposed method is 22 ms for an acquired image, which satisfies the criterion of a real-time finger vein identification system.

  12. Vein graft adaptation and fistula maturation in the arterial environment.

    Science.gov (United States)

    Lu, Daniel Y; Chen, Elizabeth Y; Wong, Daniel J; Yamamoto, Kota; Protack, Clinton D; Williams, Willis T; Assi, Roland; Hall, Michael R; Sadaghianloo, Nirvana; Dardik, Alan

    2014-05-01

    Veins are exposed to the arterial environment during two common surgical procedures, creation of vein grafts and arteriovenous fistulae (AVF). In both cases, veins adapt to the arterial environment that is characterized by different hemodynamic conditions and increased oxygen tension compared with the venous environment. Successful venous adaptation to the arterial environment is critical for long-term success of the vein graft or AVF and, in both cases, is generally characterized by venous dilation and wall thickening. However, AVF are exposed to a high flow, high shear stress, low-pressure arterial environment and adapt mainly via outward dilation with less intimal thickening. Vein grafts are exposed to a moderate flow, moderate shear stress, high-pressure arterial environment and adapt mainly via increased wall thickening with less outward dilation. We review the data that describe these differences, as well as the underlying molecular mechanisms that mediate these processes. Despite extensive research, there are few differences in the molecular pathways that regulate cell proliferation and migration or matrix synthesis, secretion, or degradation currently identified between vein graft adaptation and AVF maturation that account for the different types of venous adaptation to arterial environments.

  13. [Treatment of nontumoral portal vein thrombosis in cirrhosis].

    Science.gov (United States)

    Bañares, Rafael; Catalina, María-Vega

    2014-07-01

    Portal vein thrombosis in cirrhosis is a relatively common complication associated with the presence of an accompanying prothrombotic phenotype of advanced cirrhosis. The consequences of portal vein thrombosis are relevant because it can be associated with impaired hepatic function, might contraindicate hepatic transplantation and could increase morbidity in the surgical procedure. There is controversy concerning the most effective treatment of portal vein thrombosis, which is based on information that is seldom robust and whose primary objective is to achieve a return to vessel patency. Various studies have suggested that starting anticoagulation therapy early is associated with portal vein repatency more frequently than without treatment and has a low rate of complications. There are no proven data on the type of anticoagulant (low-molecular-weight heparins or dicoumarin agents) and the treatment duration. The implementation of TIPS is technically feasible in thrombosis without cavernous transformation and is associated with portal vein recanalization in a significant proportion of cases. Thrombolytic therapy does not appear to present an adequate balance between efficacy and safety; its use is therefore not supported for this indication. The proper definition of treatment for portal vein thrombosis requires properly designed studies to delimit the efficacy and safety of the various alternatives.

  14. Giant Intrahepatic Portal Vein Aneurysm: Leave it or Treat it?

    Science.gov (United States)

    Shrivastava, Amit; Rampal, Jagdeesh S; Nageshwar Reddy, D

    2017-03-01

    Portal vein aneurysm (PVA) is a rare vascular dilatation of the portal vein. It is a rare vascular anomaly representing less than 3% of all visceral aneurysms and is not well understood. Usually, PVA are incidental findings, are asymptomatic, and clinical symptoms are proportionally related to size. Patients present with nonspecific epigastric pain or gastrointestinal bleeding with underlying portal hypertension. PVA may be associated with various complications such as biliary tract compression, portal vein thrombosis/rupture, duodenal compression, gastrointestinal bleeding, and inferior vena cava obstruction. Differential diagnoses of portal vein aneurysms are solid, cystic, and hypervascular abdominal masses, and it is important that the radiologists be aware of their multi-modality appearance; hence, the aim of this article was to provide an overview of the available literature to better simplify various aspects of this rare entity and diagnostic appearance on different modality with available treatment options. In our case, a 55-year-old male patient came to the gastroenterology OPD for further management of pancreatitis with portal hypertension and biliary obstruction with plastic stents in CBD and PD for the same. In this article, we have reported a case of largest intrahepatic portal vein aneurysm and its management by endovascular technique. As per our knowledge, this is the largest intrahepatic portal vein aneurysm and first case where the endovascular technique was used for the treatment of the same.

  15. Lost in Location

    DEFF Research Database (Denmark)

    Hansen, Lone Koefoed

    2009-01-01

    The article investigates how users of personal satellite navigation devices (often referred to as sat-nav) are sometimes lost and led astray and argues that the satnav's aim to remove every insecurity about the correct route seems to remove the individual's conscious perception of the space...... performance, the article examines how the growing locative media industry can learn from the location-aware performative strategies employed by artists who create situated and urban performances for the curious participant. The academic frames employed in the analysis draw on psychogeography, site...

  16. [Research on optimization of imaging system of the hand vein optical properties].

    Science.gov (United States)

    Lan, Huiying; Shi, Yan; Wang, Longwu

    2013-10-01

    Due to the difficulties of the copying, vein identification has developed rapidly in recent years. The light source selection directly affects the image quality. This paper acquired by experiment the reflectivities of vein and non-vein irradiation with different wavelengths of near infra-red. Comparing the strength of reflectivities of various wave lengths, we found that there were the strongest contrasts between vein and non-vein in the 810 nm, and 810 nm near infra-red was suitable to a vein imaging light source. Finally, clear hand vein images were obtained with the selected light source.

  17. Liquid Crystals

    Science.gov (United States)

    1990-01-01

    Thermochromic liquid crystals, or TLCs, are a type of liquid crystals that react to changes in temperature by changing color. The Hallcrest/NASA collaboration involved development of a new way to visualize boundary layer transition in flight and in wind tunnel testing of aircraft wing and body surfaces. TLCs offered a new and potentially better method of visualizing the boundary layer transition in flight. Hallcrest provided a liquid crystal formulation technique that afforded great control over the sensitivity of the liquid crystals to varying conditions. Method is of great use to industry, government and universities for aerodynamic and hydrodynamic testing. Company's principal line is temperature indicating devices for industrial use, such as non-destructive testing and flaw detection in electric/electronic systems, medical application, such as diagnostic systems, for retail sale, such as room, refrigerator, baby bath and aquarium thermometers, and for advertising and promotion specials. Additionally, Hallcrest manufactures TLC mixtures for cosmetic applications, and liquid crystal battery tester for Duracell batteries.

  18. Transsplenic portal vein reconstruction–transjugular intrahepatic portosystemic shunt in a patient with portal and splenic vein thrombosis

    Directory of Open Access Journals (Sweden)

    Jason T. Salsamendi, MD

    2016-09-01

    Full Text Available Portal vein thrombosis (PVT is a potential complication of cirrhosis and can worsen outcomes after liver transplant (LT. Portal vein reconstruction–transjugular intrahepatic portosystemic shunt (PVR-TIPS can restore flow through the portal vein (PV and facilitate LT by avoiding complex vascular conduits. We present a case of transsplenic PVR-TIPS in the setting of complete PVT and splenic vein (SV thrombosis. The patient had a 3-year history of PVT complicated by abdominal pain, ascites, and paraesophageal varices. A SV tributary provided access to the main SV and was punctured percutaneously under ultrasound scan guidance. PV access, PV and SV venoplasty, and TIPS placement were successfully performed without complex techniques. The patient underwent LT with successful end-to-end anastomosis of the PVs. Our case suggests transsplenic PVR-TIPS to be a safe and effective alternative to conventional PVR-TIPS in patients with PVT and SV thrombosis.

  19. Transsplenic portal vein reconstruction-transjugular intrahepatic portosystemic shunt in a patient with portal and splenic vein thrombosis.

    Science.gov (United States)

    Salsamendi, Jason T; Gortes, Francisco J; Shnayder, Michelle; Doshi, Mehul H; Fan, Ji; Narayanan, Govindarajan

    2016-09-01

    Portal vein thrombosis (PVT) is a potential complication of cirrhosis and can worsen outcomes after liver transplant (LT). Portal vein reconstruction-transjugular intrahepatic portosystemic shunt (PVR-TIPS) can restore flow through the portal vein (PV) and facilitate LT by avoiding complex vascular conduits. We present a case of transsplenic PVR-TIPS in the setting of complete PVT and splenic vein (SV) thrombosis. The patient had a 3-year history of PVT complicated by abdominal pain, ascites, and paraesophageal varices. A SV tributary provided access to the main SV and was punctured percutaneously under ultrasound scan guidance. PV access, PV and SV venoplasty, and TIPS placement were successfully performed without complex techniques. The patient underwent LT with successful end-to-end anastomosis of the PVs. Our case suggests transsplenic PVR-TIPS to be a safe and effective alternative to conventional PVR-TIPS in patients with PVT and SV thrombosis.

  20. Leiomyosarcoma of inferior vena cava involving bilateral renal veins: Surgical challenges and reconstruction with upfront saphenous vein interposition graft for left renal vein outflow

    Directory of Open Access Journals (Sweden)

    Rishi Nayyar

    2010-01-01

    Full Text Available Leiomyosarcoma of inferior vena cava (IVC involving bilateral renal veins presents a surgical challenge. Herein, we report the successful management of two such cases using restoration of left renal venous outflow by saphenous vein interposition graft as first step of surgery. Then radical resection of tumor and right kidney was done. IVC was lastly reconstructed using Gore-Tex graft. This report highlights the surgical challenges to ensure radical resection. Furthermore, the importance of restoring left renal outflow in presence of concomitant right nephrectomy is discussed. Both the patients were disease free at six months with no loss of left renal glomerular filtration rate.

  1. Pulmonary vein isolation in the treatment of atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Kumar S

    2016-05-01

    Full Text Available Saurabh Kumar, Gregory F Michaud Cardiac Arrhythmia Service, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA, USA Abstract: Atrial fibrillation (AF is the commonest arrhythmia in humans and is associated with marked reduction in quality of life and an elevated thromboembolic risk. Paroxysmal, persistent, and permanent forms of AF have been recognized. Whilst antiarrhythmic drugs are considered as first-line therapy, the role of catheter ablation is increasing due to its superior efficacy in terms of quality of life and reduction in AF burden. The central paradigm for catheter ablation of AF is that triggers for AF are located near and within the pulmonary veins (PVs, and electrical isolation of the PVs from the left atrium forms the cornerstone of most catheter ablation strategies. Whilst paroxysmal form is generally trigger dependent, persistent and permanent forms are associated with variable interaction between triggers and "substrate" comprised of atrial and PV electrical and structural remodeling. Nevertheless, isolation of the PVs still forms a critical component of catheter ablation strategies, regardless of AF type. Procedural efficacy, however, is limited by PV conduction recovery. This is likely due to deficiencies in ablation tools or limitations of intraprocedural assessment of lesion efficacy. Careful attention to surrogates of tissue heating, such as impedance decrease and electrogram morphology changes, along with advances in catheter technology like contact force catheters may improve rates of durable PV isolation and single-procedural success. This review discusses the mechanism of paroxysmal AF with particular focus on the role of the PVs in AF initiation and PV isolation in the management of AF. Keywords: contact force, lesion transmurality, radiofrequency catheter ablation, paroxysmal atrial fibrillation, electrophysiology, AF

  2. The anatomical variations of sylvian veins and cisterns.

    Science.gov (United States)

    Aydin, I H; Tüzün, Y; Takçi, E; Kadioğlu, H H; Kayaoğlu, C R; Barlas, E

    1997-06-01

    The anatomical variations of sylvian vein and cistern were investigated during the pterional approach in 750 operative cases with different pathologies. All patients were operated on at the Neurosurgical Department of Ataturk University Medical School, Erzurum, Turkiye. The patients underwent surgery for the lesions necessitating the right or left pterional approach. The findings were recorded during surgical intervention and observed through the operative sketches of the pathologies, the slides, and videotapes of the operations. In our study, we surgically classified the variations of sylvian vein, according to its branching and draining patterns. Type I: The fronto-orbital (frontosylvian), fronto-parietal (parietosylvian) and anterior temporal (temporosylvian) veins drain into one sylvian vein. Type II: Two superficial sylvian veins with separated basal vein draining into the sphenoparietal and Rosenthal's basal vein. Type III: Two superficial sylvian veins draining into the sphenoparietal and the superior petrosal veins. Type IV: Hypoplastic superficial sylvian vein and the deep one. Four types of sylvian vein variations were defined as follows. The type I was seen in 52.8% (n = 396), the type II was found in 19.2% (n = 144), type III was recorded in 18.2% (n = 137), and type IV, or hypoplastic and deep form was discovered in 9.8% (n = 73) of patients. The coursing of sylvian vein was in the temporal side (Temporal Coursing) in 62.4 percent of the cases (n = 469), in the frontal side (Frontal Coursing) in 25 % of the patients (n = 187) and in 9 percent of the cases (n = 67) in the deep localization (Deep Coursing). Only 3.6% of the cases (n = 27) showed Mixed Coursing. The variations of the sylvian cisterns were classified into three types, according to the relationships between the lateral fronto-orbital gyrus and the superior temporal gyrus. In Sylvian type, the frontal and temporal lobes are loosely (Sylvian Type A, wide and large) or tightly (Sylvian Type B

  3. Latin American Consensus on Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    Francisco J. Rodriguez

    2016-01-01

    Full Text Available The introduction of anti-VEGF agents has allowed unprecedented progress in the management and treatment of ophthalmologic conditions characterized by an increased vascular permeability and intraocular neovascularization. One of these conditions is retinal vein occlusion (RVO.  RVO is one of the most common causes of reduced vision due to retinal vascular disease. Without timely treatment, macular edema, macular ischemia, neovascularization and other potential sequelae of RVO can lead to photoreceptor cell death and consequently to irreversible vision loss.   Treatments for this indication that have been recently approved by several regulatory agencies throughout the world include: the VEGF inhibitor ranibizumab (Lucentis, Genentech, the VEGF and placental growth factor inhibitor aflibercept (Eylea, Regeneron Pharmaceuticals and Bayer HealthCare, and a slow release intravitreal implant of dexamethasone (Ozurdex, Allergan. In addition bevacizumab (Avastin, Genentech has been used extensively in an off-label manner.   These new treatments allow us to preserve vision for many RVO patients who could not have expected such favorable results just 5 or 6 years ago. However, not every treatment is effective for every patient, and whether one option is superior to another or a combination of options is superior to monotherapy, have yet to be definitively determined.   A growing body of literature with strong evidence supports the use of these new treatments. However, in several instances the literature is not conclusive to support unified management of RVO. This document is a summary analysis on RVO assembled by a group of specialists summoned by the Pan-American Vitreo-Retinal Society (SPRV to participate in this Latin American consensus.

  4. 门静脉血栓的MRI诊断%MRI Diagnosis of Portal Vein Thrombosis

    Institute of Scientific and Technical Information of China (English)

    覃智颖; 张应和; 范真真; 梁晓芬; 苏敏仪

    2012-01-01

    目的 探讨MRI诊断门静脉血栓(PVT)的价值.方法 回顾性分析经临床随访证实的9例PVT患者的资料,所有病例均行常规MRI平扫及三维容积超快速多期动态增强扫描( LAVA).结果 9例肝PVT中,4例位于门静脉左支,2例门静脉右支,3例位于门静脉主干,其中1例同时累及门静脉右支.MRI均能显示门静脉及其分支内血栓异常信号,平扫T1WI及T2WI流空信号消失,增强扫描各期血栓均无强化,管腔内出现充盈缺损.结论 MRI是诊断PVT的有效影像学检查方法.%Objective To discuss the diagnostic value of MR Imaging for portal vein thrombus. Methods Retrospective analysis of 9 cases of portal vein thrombosis confirmed by clinical follow-up, all the cases were performed by plain scan and Liver Acquisition with Volume Acceleration MRI. Results During these 9 PVT, 4 cases thrombus located in the left branch of portal vein, 2 in the right branch of portal vein,3 in the trunk of portal, and lease two branchs of portal compromised. MRI can well demonstrate the abnormal signals of the thrombus in the portal vein or its branch, normal flowing void disappeared in the TlWI and T2WI of the MR plain scan, and there were no enhancement in any phases of the thronbus. showed filling defect within the lumen. Conclusion MRI is the effective radiographie technique for the diagnosis of PVT.

  5. Experimental characterization of transitional unsteady flow inside graft-to-vein junction

    Science.gov (United States)

    Arslan, Nurullah

    1999-12-01

    Turbulent flow measurements were conducted inside an upscaled end-to-side model of a human arteriovenous graft using laser Doppler anemometry under steady and pulsatile flow conditions. This research is clinically relevant because turbulence and local fluid dynamic factors such as wall shear stress have been implicated as localization factors for intimal hyperplasia, the main cause of arteriovenous graft failure. This research is the first experimental study measuring the turbulence level and Reynolds stresses quantitatively inside an in vitro model representing an arteriovenous graft under pulsatile flow conditions. The turbulence intensity, Reynolds stresses, and mean velocities have been measured for steady and pulsatile flow. Reynolds numbers for steady flow were 1060, 1820, 2530 and 2720. The peak, mean and minimum Reynolds numbers were 2470, 1762 and 1198 for the pulsatile flow, respectively. The flow division was 90% entering from the graft inlet and 10% entering from the distal vein segment for steady flow measurements. It was 85% entering from the graft inlet and 15% entering from the distal vein segment for pulsatile flow measurements. Measurements were made thirteen axial locations in the plane of the bifurcation at the venous anastomosis. At high Reynolds numbers (>2000), the velocity profiles were blunt at the inlet of the arteriovenous graft. High turbulent fluctuations and Reynolds stresses were found in the proximal vein segment opposite to the vein side of the anastomosis for steady and pulsatile flows. Steady flow fluctuation values were 20-30% larger than pulsatile flow values for the same instantaneous Reynolds number. The highest value of the Reynolds stress was found to be 2080 and 1400 dynes/cm2 steady and pulsatile flow, respectively. A separation region was observed at the toe side of the arteriovenous graft. Strong secondary flows were found at the inlet to and inside the proximal vein segment under steady flow conditions. The results of

  6. Location-routing problems

    Energy Technology Data Exchange (ETDEWEB)

    Laporte, G.

    1987-01-01

    Location-routing problems involve simultaneously locating a number of facilities among candidate sites and establishing delivery routes to a set of users in such a way that the total system cost is minimized. This paper presents a survey of such problems. It includes some applications and examples of location-routing problems, a description of the main heuristics that have been developed for such problems, and reviews of various formulations and algorithms used in solving these problems. A more detailed review is given of exact algorithms for the vehicle routing problem, three-index vehicle flow formulations, and two-index vehicle flow formulations and algorithms for symmetrical and non-symmetrical problems. It is concluded that location-routing problem research is a fast-growing area, with most developments occurring over the past few years; however, research is relatively fragmented, often addresses problems which are too specific and contains several voids which have yet to be filled. A number of promising research areas are identified. 137 refs., 3 figs.

  7. The Czech Locative Chameleon

    Directory of Open Access Journals (Sweden)

    Tarald Taraldsen

    2007-12-01

    Full Text Available We show that under certain circumstances, the Czech locative prepositions (LOC show up as directional prepositions (DIR and vice versa, (under different circumstances the Czech DIR PPs show up as LOC. We argue that such a chameleon life of the PPs is structurally dependent.

  8. The Czech Locative Chameleon

    OpenAIRE

    Tarald Taraldsen; Lucie Medová

    2007-01-01

    We show that under certain circumstances, the Czech locative prepositions (LOC) show up as directional prepositions (DIR) and vice versa, (under different circumstances) the Czech DIR PPs show up as LOC. We argue that such a chameleon life of the PPs is structurally dependent.

  9. Locative Inversion in English

    NARCIS (Netherlands)

    Broekhuis, H.

    2005-01-01

    This article aims at reformulating in more current terms Hoekstra and Mulder’s (1990) analysis of the Locative Inversion (LI) construction. The new proposal is crucially based on the assumption that Small Clause (SC) predicates agree with their external argument in phi-features, which may be morphol

  10. Location-based games

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine

    In this dissertation, it is explored which prerequisites are necessary in location-based games (LBGs) to make meaningful the meeting between players and spatiality with an emphasis on physical locations. Throughout the dissertation, it has been shown that LBGs affect players’ perception of and be......In this dissertation, it is explored which prerequisites are necessary in location-based games (LBGs) to make meaningful the meeting between players and spatiality with an emphasis on physical locations. Throughout the dissertation, it has been shown that LBGs affect players’ perception...... of and behavior in everyday spaces, as the games reside on the boundaries between the continuums of play and ordinary, authentic and fictional, and as they merge physical and digital media. These are termed the six dimensions of LBGs. LBGs let the player explore the boundaries between these dimensions...... experiences of being in the world and the creation of meaning. The theory on motivation defines what motivation consists of and how it relates to our actions. This theory has been combined with theories concerning play and play culture, digital media, (digital) games, (optimal) experiences, landscape...

  11. RFID Location Algorithm

    Directory of Open Access Journals (Sweden)

    Wang Zi Min

    2016-01-01

    Full Text Available With the development of social services, people’s living standards improve further requirements, there is an urgent need for a way to adapt to the complex situation of the new positioning technology. In recent years, RFID technology have a wide range of applications in all aspects of life and production, such as logistics tracking, car alarm, security and other items. The use of RFID technology to locate, it is a new direction in the eyes of the various research institutions and scholars. RFID positioning technology system stability, the error is small and low-cost advantages of its location algorithm is the focus of this study.This article analyzes the layers of RFID technology targeting methods and algorithms. First, RFID common several basic methods are introduced; Secondly, higher accuracy to political network location method; Finally, LANDMARC algorithm will be described. Through this it can be seen that advanced and efficient algorithms play an important role in increasing RFID positioning accuracy aspects.Finally, the algorithm of RFID location technology are summarized, pointing out the deficiencies in the algorithm, and put forward a follow-up study of the requirements, the vision of a better future RFID positioning technology.

  12. Crime Location Choice

    NARCIS (Netherlands)

    Bernasco, Wim; Ruiter, Stijn

    2014-01-01

    Most behavior of interest to social scientists is choice behavior: actions people commit while they could also have done something else. In geographical and environmental criminology, a new framework has emerged for analyzing individual crime location choice. It is based on the principle of random u

  13. A Dorsal Hand Vein Recognition-based on Local Gabor Phase Quantization with Whitening Transformation

    OpenAIRE

    K. Premalatha; Anantha kumar T; Natarajan A M

    2014-01-01

    The hand vein pattern is a biometric feature in which the actual pattern is the shape of the vein network and its characteristics are the vein features. This paper investigates a new approach for dorsal hand vein pattern identification from grey level dorsal hand vein information. In this study Gabor filter quadrature pair is employed to compute locally in a window for every pixel position to extract the phase information. The phases of six frequency coefficients are quantized and it is used ...

  14. Photonic crystals

    CERN Document Server

    Busch, Kurt; Wehrspohn, Ralf B; Föll, Helmut

    2006-01-01

    The majority of the contributions in this topically edited book stems from the priority program SPP 1113 ""Photonische Kristalle"" run by the Deutsche Forschungsgemeinschaft (DFG), resulting in a survey of the current state of photonic crystal research in Germany. The first part of the book describes methods for the theoretical analysis of their optical properties as well as the results. The main part is dedicated to the fabrication, characterization and modeling of two- and three-dimensional photonic crystals, while the final section presents a wide spectrum of applications: gas sensors, micr

  15. Coexistence of Multiple Ileal Neuroendocrine Tumors and Idiopathic Myointimal Hyperplasia of Mesenteric Veins: Coincidence or Consequence? Case Report and Review of Literature.

    Science.gov (United States)

    Guadagno, Elia; Del Basso De Caro, Marialaura; Del Prete, Ester; D'Armiento, Francesco Paolo; Campione, Severo

    2016-10-01

    In the present case, we report the association of multiple ileal neuroendocrine tumors and idiopathic myointimal hyperplasia of the mesenteric veins, 2 rare conditions that could have an etiopathogenetic relationship. Idiopathic myointimal hyperplasia of mesenteric veins implies a near-total obliteration of venular vessels, which can lead to hypoxic disorders. Hypoxia in tumors is associated with increased metastatic potential and resistance to radiotherapy and chemotherapy. Herein we speculated on the existence of a relationship between hypoxia and multiple location of neuroendocrine tumors. © The Author(s) 2016.

  16. Percutaneus treatment of varicose veins with bipolar radiofrequency ablation

    Energy Technology Data Exchange (ETDEWEB)

    Boon, R.; Akkersdijk, G.J.M. [Department of Surgery, Spaarne Hospital, Hoofddorp (Netherlands); Nio, D., E-mail: dnio@spaarneziekenhuis.n [Department of Surgery, Spaarne Hospital, Hoofddorp (Netherlands)

    2010-07-15

    The traditional surgical treatment of an incompetent great saphenous vein (GSV) and small saphenous vein (SSV) is challenged by endovenous techniques. Bipolar radio frequency induced thermo therapy (RFITT) is a new endovenous treatment, which occludes the vein by using the venous wall as a conductor. Linear endovenous energy densitiy (LEED) describes the amount of energy used for vein closure. Material/methods: From March 2007 till April 2009, two cohorts (23 W and 20 W) were compared, respectively 280 and 178 patients. GSV and SSV were separately analyzed. Follow-up was performed at 3 weeks and 1 year post-operatively with duplex ultrasound, to assess vein closure and perioperative complaints. A visual analog scale (VAS) pain score (range 0-10) was documented. For patients operated after October 2008 follow-up was performed at least 6 months after surgery. Results: 528 GSV and 76 SSV were treated. For the GSV a significant difference in LEED 40.8 17.1 in the 20 W cohort was found, resulting in higher occlusion rates 90.6% compared to 82.7% after 3 weeks. Follow-up of 1 year in the 20 W cohort showed 88.7% occlusion. Multivariate analysis showed that pullback speed (OR 3.7, CI 1.1-12.4) and CEAP classification (OR 3.1, CI 1.7-5.6) were significant predictors for vein occlusion. Despite a higher LEED, post-operative complaints were not significantly worse. Conclusion: RFITT is a safe and effective method to treat incompetent saphenous veins. Slower pullback speed with higher LEED results in higher closure rates without causing more pain.

  17. Ocular neovascularization associated with central and hemicentral retinal vein occlusion.

    Science.gov (United States)

    Hayreh, Sohan Singh; Zimmerman, M Bridget

    2012-09-01

    To investigate the incidence of ocular neovascularization (NV) in central and hemicentral retinal vein occlusion. The study comprised consecutive 912 (673 nonischemic and 239 ischemic) central retinal vein occlusion and 190 (147 nonischemic, 43 ischemic) hemicentral retinal vein occlusion eyes. Ophthalmic evaluation at initial and follow-up visits included recording visual acuity, visual fields, and detailed anterior segment and fundus examinations and fluorescein fundus angiography. In ischemic central retinal vein occlusion, within 6 months from time of onset, the cumulative probability of development of iris NV was 49%, angle NV 37%, NV glaucoma 29%, retinal NV 9%, and disk NV 6%. More severe peripheral retinal hemorrhages were significantly associated with iris NV (P = 0.005), angle NV (P = 0.0004), and NV glaucoma (P = 0.012). Eyes that developed disk NV had more cotton wool spots (P = 0.058) than those without. In ischemic hemicentral retinal vein occlusion, within 12 months of onset, the cumulative probability of development of retinal NV was 29%, disk NV 12%, and iris NV 12%; within 6 months of onset, angle NV was found in 10% and NV glaucoma in 5%. Anterior chamber flare was associated with anterior segment NV and may precede the development of NV. Patients who developed NV were significantly younger, and there was a greater prevalence of NV glaucoma in patients with primary open angle glaucoma. In ischemic central retinal vein occlusion, anterior segment NV is much more common than posterior segment NV, and the cumulative chance of developing anterior segment NV is maximum during the first 6 months. In ischemic hemicentral retinal vein occlusion, posterior segment NV is much more common than anterior segment NV.

  18. Assessment of the efficacy and safety of steam vein sclerosis as compared to classic surgery in lower extremity varicose vein management.

    Science.gov (United States)

    Woźniak, Witold; Mlosek, Robert K; Ciostek, Piotr

    2015-04-01

    For the last 10 years, endovenous thermal ablation methods have gradually predominated over the classic Babcock procedure in varicose vein treatment. Steam vein sclerosis is the newest thermal ablation technique. To assess the efficacy and safety of steam vein sclerosis as compared to the Babcock procedure in lower extremity varicose vein treatment. One hundred and two adult subjects with varicose veins of clinical grade C2 to C6 according to the CEAP classification, treated with varicose vein surgery between 2010 and 2012, were enrolled in the study. These were subdivided into two groups: the study group of 52 patients treated with endovenous steam vein sclerosis and the control group of 50 patients treated with the Babcock procedure. A single lower extremity with isolated great or small saphenous vein insufficiency was operated on in each subject. The groups were compared for demography, disease severity, involved veins, potential perioperative and postoperative complications, as well as treatment efficacy based on the VCSS score reduction. There were no statistically significant differences between the groups in terms of demography, disease severity, involved veins, or perioperative and postoperative complications. The treatment efficacy of both methods, assessed based on the recurrence rate and the quantitative VCSS score reduction, was similar. Clinically significant recanalisation was observed in 1 (1.9%) patient in the study group. The efficacy and safety analysis shows that steam vein sclerosis is a safe, simple method which can be recommended as effective varicose vein treatment.

  19. Electric current locator

    Science.gov (United States)

    King, Paul E [Corvallis, OR; Woodside, Charles Rigel [Corvallis, OR

    2012-02-07

    The disclosure herein provides an apparatus for location of a quantity of current vectors in an electrical device, where the current vector has a known direction and a known relative magnitude to an input current supplied to the electrical device. Mathematical constants used in Biot-Savart superposition equations are determined for the electrical device, the orientation of the apparatus, and relative magnitude of the current vector and the input current, and the apparatus utilizes magnetic field sensors oriented to a sensing plane to provide current vector location based on the solution of the Biot-Savart superposition equations. Description of required orientations between the apparatus and the electrical device are disclosed and various methods of determining the mathematical constants are presented.

  20. Ribbon Crystals

    DEFF Research Database (Denmark)

    Bohr, Jakob; Markvorsen, Steen

    2013-01-01

    A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons...

  1. Therapeutic Crystals

    Science.gov (United States)

    Bond, Charles S.

    2014-01-01

    Some readers might not fully know what the difference is between crystallography, and the "new age" practice of dangling crystals around the body to capitalise on their healing energy. The latter is often considered to be superstition, while ironically, the former has actually resulted in real rationally-based healing of human diseases…

  2. Veias linfonodais: uma causa pouco conhecida de varizes Lymph node veins: a little-known cause of varicose veins

    Directory of Open Access Journals (Sweden)

    André Paciello Romualdo

    2008-12-01

    Full Text Available As veias linfonodais fazem parte de uma rede venosa no triângulo de Scarpa, que liga em vários pontos o sistema venoso superficial às veias profundas, e podem tanto ser causa de incompetência do sistema venoso superficial quanto estar envolvidas na recorrência pós-safenectomia. Na rotina diária dos exames de Doppler venoso de membros inferiores, temos notado de maneira cada vez mais freqüente a associação das veias linfonodais com varizes primárias e recorrentes. A adequada caracterização dessas veias pode ajudar na compreensão do mecanismo fisiopatológico do aparecimento das varizes e permitir um controle e tratamento mais dirigidos. Este artigo lança luz sobre os aspectos anatômicos e fisiológicos das veias linfonodais, objetivando chamar a atenção dos profissionais envolvidos no diagnóstico de doenças venosas dos membros inferiores para uma causa pouco difundida de varizes.Lymph node veins are part of a venous network in Scarpa"s triangle, communicating in many points the superficial venous system and the deep veins, and may either be the cause of incompetence of the superficial venous system, or be involved in recurrent varicose veins after saphenous vein stripping. In the daily routine of venous Doppler examination of the lower extremities, an increasingly frequent association of lymph node veins with primary and/or recurrent varicose veins has been noticed. Appropriate characterization of these veins may help to understand the pathophysiological mechanism of varicose vein appearance and provide a more focused approach to follow-up and treatment. This article sheds some light on the anatomical and physiological aspects of lymph node veins, drawing the attention of professionals involved in the diagnosis of venous disorders of the lower extremities to a little-known cause of varicose veins.

  3. Evaluation of Deep Vein Thrombosis with Multidetector Row CT after Orthopedic Arthroplasty: a Prospective Study for Comparison with Doppler Sonography

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Sung Su; Kim, Youn Jeong; Chun, Yong Sun; Kim, Won Hong [Inha University, College of Medicine, Incheon (Korea, Republic of); Kim, Jeong Ho; Park, Chul Hi [Gachon University, Gil Medical Center, Incheon (Korea, Republic of)

    2008-02-15

    This prospective study evaluated the ability of indirect 16-row multidetector CT venography, in comparison with Doppler sonography, to detect deep vein thrombosis after total hip or knee replacement. Sixty-two patients had undergone orthopedic replacement surgery on a total of 30 hip joints and 54 knee joints. The CT venography (scan delay time: 180 seconds; slice thickness/increment: 2/1.5 mm) and Doppler sonography were performed 8 to 40 days after surgery. We measured the z-axis length of the beam hardening artifact that degraded the image quality so that the presence of deep vein thrombosis couldn't be evaluated on the axial CT images. The incidence and location of deep vein thrombosis was analyzed. The diagnostic performance of the CT venograms was evaluated and compared with that of Doppler sonography as a standard of reference. The z-axis length (mean{+-}standard deviation) of the beam hardening artifact was 4.5{+-}0.8 cm in the arthroplastic knees and 3.9{+-}2.9 cm in the arthroplastic hips. Deep vein thrombosis (DVT) was found in the popliteal or calf veins on Doppler sonography in 30 (48%) of the 62 patients. The CT venography has a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 90%, 97%, 96%, 91% and 94%, respectively. The ability of CT venography to detect DVT was comparable to that of Doppler sonography despite of beam hardening artifact. Therefore, CT venography is feasible to use as an alternative modality for evaluating postarthroplasty patients.

  4. Novel findings of the anatomy and variations of the axillary vein and its tributaries.

    Science.gov (United States)

    Yang, Hee-Jun; Gil, Young-Chun; Jin, Jeong-Doo; Cho, Hyejin; Kim, Hyun; Lee, Hye-Yeon

    2012-10-01

    The anatomy and variations of the axillary vein has significant implications in various invasive procedures such as venous access, axillary block, arteriovenous fistula creation, axillary node dissection, breast augmentation, and other surgical procedures involving the axilla. To clarify the anatomy of the axillary vein and its tributaries, 40 cadaveric upper extremities were examined after dissection and were classified into several types according to the courses and terminations of brachial veins. The brachial veins ended separately (Type A; 72.5%) or made a common brachial vein (Type B; 27.5%) to enter the basilic vein or the axillary vein. The basilic vein was absent in 5.0% of the specimens. Duplication of the axillary vein was observed in 17.5% of the specimens and the lateral venous channel running along the lateral wall of the axilla was observed in 40.0% of the specimens. The most common drainage vein of the deep brachial vein was the lateral brachial vein (67.5%). The anterior circumflex humeral vein also emptied into the lateral brachial vein in 67.5% of the specimens. The posterior circumflex humeral vein crossed posterior side of the brachial plexus to join either the axillary vein (45.0%) or subscapular vein (42.5%). Perforation of the lateral root of median nerve by a lateral brachial vein, a common brachial vein, or a venous channel was observed in 15.0% of the specimens. Other venous variations accompanying the variations of the axillary artery or the brachial artery are described herein. The clinical importance of these findings is described in the discussion. Copyright © 2012 Wiley Periodicals, Inc.

  5. Photonic crystals principles and applications

    CERN Document Server

    Gong, Qihuang

    2013-01-01

    IntroductionPrimary Properties of Photonic CrystalsFabrication of Photonic CrystalsPhotonic Crystal All-Optical SwitchingTunable Photonic Crystal FilterPhotonic Crystal LaserPhotonic Crystal Logic DevicesPhotonic Crystal Sensors

  6. [The internal thoracic blood vessels (internal thoracic arteries and veins) and their practical significance].

    Science.gov (United States)

    Jelicić, N; Djordjević, Lj; Stosić, T

    1996-01-01

    cartilage (adults--35% and children--45%), and most rarely, the bifurcation of the artery was at the level of the seventh costal cartilage (adults--10% and children--8%). The internal thoracic vein that accompanies the same named artery, could be either single or double, on one or both sides. In cases of double veins-the artery was situated between the two of them, but in cases of single vein-the vein was located medially to the artery. In 82% of cases in the adult group, and in 69% of cases in the children-group, there were two veins accompanying the artery. The right and the left internal thoracic veins were connected in the region of the sternal bone by the retrosternal venous net (specifically in the region of the manubrium) and by one venous vessel lying in front of the xiphoid process. According to the position and the course of that venous vessel it could be called "arcus venosus prexiphoideus". The internal thoracic blood vessels were enclosed by the unique fascial sheath. They were superiorly separated from the costal pleura by the endothoracic fascia and inferiorly by the transversal thoracic muscle (m. transversus thoracis). The safest approach to the internal thoracic artery was at the level of the second and the third intercostal space. During the approach through some of the lower intercostal spaces it was necessary to be very careful because they could be narrowed at their anterior ends.

  7. Impact of short-term hemodialysis catheters on the central veins: a catheter venographic study

    Energy Technology Data Exchange (ETDEWEB)

    Oguzkurt, Levent E-mail: loguzkurt@yahoo.com; Tercan, Fahri; Torun, Dilek; Yildirim, Tuelin; Zuemruetdal, Ayseguel; Kizilkilic, Osman

    2004-12-01

    Objective: To determine the incidence of pericatheter sleeve formation, thrombus formation, and stenosis of the central veins in hemodialysis patients with temporary catheters. Methods and material: In this prospective study, 57 patients (40 males, 17 females) with temporary dialysis catheters had catheter venography by pulling back the catheter just before removal. Patient's age range was 25-87 years (mean age, 51 years). The venographic studies were evaluated for pericatheter sleeve formation, thrombus formation, and stenosis of the brachiocephalic vein (BCV) and the superior vena cava (SVC). The IJV could only be evaluated if there was adequate filling during contrast administration. In a subgroup of patients who had had only right IJV or only right SCV catheters, impact of these catheters on the central veins was compared. Results: The catheter location was right internal jugular vein (IJV) in 26 cases, right subclavian vein (SCV) in 27 cases, left IJV in 1 case, and left SCV in 3 cases. Thirty-two patients (56%) had had only one temporary catheter and the rest had had more than one inserted. The mean dwell time for the catheters was 21 days (range 7-59 days). A pericatheter sleeve was detected on venography in 32 (56%) patients and thrombus formation was noted in 16 patients (28%). A total of 41 patients (72%) exhibited pericatheter sleeve and/or thrombus formation. While 19 of the 32 patients (59%) without previous catheterization had a sleeve around the catheter, only 13 (52%) of 25 patients who had had multiple catheters inserted had a sleeve (P>0.05). Of the eight patients (14%) with BCV stenosis, two had >50% stenosis. Only one patient (2%) had mild stenosis of the SVC. Three patients out of 15 (20%) who had diagnostic venography for the IJV had severe stenosis of the vein. Pericatheter sleeve formation was more frequent in women (P<0.05). However, there were no statistical differences with respect to pericatheter sleeve formation, luminal filling

  8. Multiple ligation of the proximal greater saphenous vein in the CHIVA treatment of primary varicose veins

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    Roberto Delfrate

    2014-06-01

    Full Text Available Saphenous femoral disconnection is the key point of most surgical techniques in the treatment of primary varicose vein surgery. The aim of this study is to compare and analyze different techniques for conservative saphenousfemoral ligation or disconnection. These techniques can be to perform mini invasive open surgery and are suitable for implementation of the conservative hemodynamic correction of venous insufficiency (CHIVA method. The aim was to present the follow-up by retrospective analysis of three different ligation-disconnection techniques of the proximal great saphenous vein (GSV according to the CHIVA method at the GSV end, i.e. between the very end of the GSV and the first arch tributary, according to the CHIVA method. The first thecnique consisted of a surgical division (crossotomy. The other two consisted of triple superposed ligation with No. 2 non-absorbable braided coated suture without division labeled TSFL (triple saphenous flush ligation and No. 0 polypropylenene ligation TPL (triple polypropylene ligation. The difference between TSFL and TPL was in the thickness and type of material of the thread, though both were non-absorbable. The follow up of 56 TPL procedures, 61 crossotomy procedures, and 82 TSFL procedures was analysed. The follow-up consisted of checking the sapheno-femoral junction occlusion with Duplex color ultra sound. The incidence rates of neovascularization (new vessels in the ligation or surgical disconnection site with saphenous-femoral reflux during the Valsalva maneuver were: 4.9% for the crossotomy group, 6.1% for the TSFL group and 37.5% for the TPL group. The data analysed show satisfactory results with both crossotomy and TSFL. Crossotomy has proven to be an effective technique for performing saphenous-femoral disconnection, but TSFL could also be a reliable, safe and low-cost varicose mini-invasive surgery in outpatients. TPL appeared to be less reliable.

  9. Evaluation of endoscopic vein extraction on structural and functional viability of saphenous vein endothelium

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    Lu Xiu-Gui

    2011-06-01

    Full Text Available Abstract Objectives Endothelial injury during harvest influences graft patency post CABG. We have previously shown that endoscopic harvest causes structural and functional damage to the saphenous vein (SV endothelium. However, causes of such injury may depend on the extraction technique. In order to assess this supposition, we evaluated the effect of VirtuoSaph endoscopic SV harvesting technique (VsEVH on structural and functional viability of SV endothelium using multiphoton imaging, biochemical and immunofluorescence assays. Methods Nineteen patients scheduled for CABG were prospectively identified. Each underwent VsEVH for one portion and "No-touch" open SV harvesting (OSVH for another portion of the SV. A two cm segment from each portion was immersed in GALA conduit preservation solution and transported overnight to our lab for processing. The segments were labeled with fluorescent markers to quantify cell viability, calcium mobilization and generation of nitric oxide. Morphology, expression, localization and stability of endothelial caveolin, eNOS, von Willebrand factor and cadherin were evaluated using immunofluorescence, Western blot and multiphoton microscopy (MPM. Results Morphological, biochemical and immunofluorescence parameters of viability, structure and function were well preserved in VsEVH group as in OSVH group. However, tonic eNOS activity, agonist-dependent calcium mobilization and nitric oxide production were partially attenuated in the VsEVH group. Conclusions This study indicates that VirtuoSaph endoscopic SV harvesting technique preserves the structural and functional viability of SV endothelium, but may differentially attenuate the vasomotor function of the saphenous vein graft. Ultramini-Abstract Endoscopic extraction preserved the structure and function, but attenuated the calcium mobilization and nitric oxide generation in human SV endothelium.

  10. Finger Vein Recognition Based on Personalized Weight Maps

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    Lu Yang

    2013-09-01

    Full Text Available Finger vein recognition is a promising biometric recognition technology, which verifies identities via the vein patterns in the fingers. Binary pattern based methods were thoroughly studied in order to cope with the difficulties of extracting the blood vessel network. However, current binary pattern based finger vein matching methods treat every bit of feature codes derived from different image of various individuals as equally important and assign the same weight value to them. In this paper, we propose a finger vein recognition method based on personalized weight maps (PWMs. The different bits have different weight values according to their stabilities in a certain number of training samples from an individual. Firstly we present the concept of PWM, and then propose the finger vein recognition framework, which mainly consists of preprocessing, feature extraction, and matching. Finally, we design extensive experiments to evaluate the effectiveness of our proposal. Experimental results show that PWM achieves not only better performance, but also high robustness and reliability. In addition, PWM can be used as a general framework for binary pattern based recognition.

  11. Coronary magnetic resonance vein imaging: imaging contrast, sequence, and timing.

    Science.gov (United States)

    Nezafat, Reza; Han, Yuchi; Peters, Dana C; Herzka, Daniel A; Wylie, John V; Goddu, Beth; Kissinger, Kraig K; Yeon, Susan B; Zimetbaum, Peter J; Manning, Warren J

    2007-12-01

    Recently, there has been increased interest in imaging the coronary vein anatomy to guide interventional cardiovascular procedures such as cardiac resynchronization therapy (CRT), a device therapy for congestive heart failure (CHF). With CRT the lateral wall of the left ventricle is electrically paced using a transvenous coronary sinus lead or surgically placed epicardial lead. Proper transvenous lead placement is facilitated by the knowledge of the coronary vein anatomy. Cardiovascular MR (CMR) has the potential to image the coronary veins. In this study we propose and test CMR techniques and protocols for imaging the coronary venous anatomy. Three aspects of design of imaging sequence were studied: magnetization preparation schemes (T(2) preparation and magnetization transfer), imaging sequences (gradient-echo (GRE) and steady-state free precession (SSFP)), and imaging time during the cardiac cycle. Numerical and in vivo studies both in healthy and CHF subjects were performed to optimize and demonstrate the utility of CMR for coronary vein imaging. Magnetization transfer was superior to T(2) preparation for contrast enhancement. Both GRE and SSFP were viable imaging sequences, although GRE provided more robust results with better contrast. Imaging during the end-systolic quiescent period was preferable as it coincided with the maximum size of the coronary veins.

  12. Alteration and vein mineralization, Ladwig uranium mine, Jefferson County, Colorado

    Science.gov (United States)

    Wallace, Alan R.

    1979-01-01

    Uranium ore at the Ladwig mine, Jefferson County, Colo., occurs in steeply dipping, northwest-striking faults and related fractures with a carbonate-adularia assemblage that forms in altered wallrocks and fills veins. The faults occur between large intrusive pegmatites and garnetiferous gneisses of Precambrian age, and were reactivated as the result of the early Paleocene uplift of the Front Range foothills. Mineralization in the deposit includes both wallrock alteration and vein filling. Alteration was intense but local, and chiefly involved the carbonatization of mafic minerals in the wallrocks. Felsic minerals in the wallrocks are relatively unaltered. The veins are filled with an adularia-pitchblende-carbonate assemblage with minor related sulfides and coffinite. Many of the iron-bearing carbonates in both the alteration and vein assemblages have been altered to hematite. The mineralization and alteration are believed to have formed in response to initially high amounts of CO2 and the subsequent release of dissolved CO2 by boiling or effervescence. Uranium, carried in a dicarbonate complex, was precipitated directly as pitchblende when the CO2 was released. The expulsion of H+ during boiling created a net oxidizing environment which oxidized the iron-bearing carbonates. Late stage calcite and sulfides were deposited in existing voids in the veins.

  13. Hand Vein Recognition Based on Improved Template Matching

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    Jun Wang

    2014-12-01

    Full Text Available An improved template-construction method for hand vein recognition is presented. The accomplishment of the new algorithm involves several steps. First, we design the power-controlled multispectral vein acquisition handset to establish high-quality hand vein database. Second, we propose an improved valley-shaped enhancement operator with NiBlack algorithm to realize vein segmentation. Third, we get a basic-shaped template after dilation and erosion operation in the four neighborhoods firstly, and then we can get the final matching template combining all the shapes after the process of filling the connected region whose threshold is smaller than the one we set according to the experiment effect. Finally we design the hand vein recognition experiments using the designed template and traditional template respectively. The recognition rate of the improved template is 96.6% under the 1:1 mode and 95.75% under the 1:N mode while the recognition rate of the traditional template is 89.2 under the 1:1 mode and 88.2 under the 1:N mode.

  14. Improved Quantification of Cerebral Vein Oxygenation Using Partial Volume Correction.

    Science.gov (United States)

    Ward, Phillip G D; Fan, Audrey P; Raniga, Parnesh; Barnes, David G; Dowe, David L; Ng, Amanda C L; Egan, Gary F

    2017-01-01

    Purpose: Quantitative susceptibility mapping (QSM) enables cerebral venous characterization and physiological measurements, such as oxygen extraction fraction (OEF). The exquisite sensitivity of QSM to deoxygenated blood makes it possible to image small veins; however partial volume effects must be addressed for accurate quantification. We present a new method, Iterative Cylindrical Fitting (ICF), to estimate voxel-based partial volume effects for susceptibility maps and use it to improve OEF quantification of small veins with diameters between 1.5 and 4 voxels. Materials and Methods: Simulated QSM maps were generated to assess the performance of the ICF method over a range of vein geometries with varying echo times and noise levels. The ICF method was also applied to in vivo human brain data to assess the feasibility and behavior of OEF measurements compared to the maximum intensity voxel (MIV) method. Results: Improved quantification of OEF measurements was achieved for vessels with contrast to noise greater than 3.0 and vein radii greater than 0.75 voxels. The ICF method produced improved quantitative accuracy of OEF measurement compared to the MIV approach (mean OEF error 7.7 vs. 12.4%). The ICF method provided estimates of vein radius (mean error partial volume maps (root mean-squared error partial volume estimates from the ICF method.

  15. EndoVascular Laser Therapy (EVLT of Varicose Veins

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    S. Akhlaghpour

    2005-08-01

    Full Text Available Introduction & Background: Tens of millions of people – up to 40% of women and 25% of men – suffer from lower limb varicose veins. Several risk factors are also identified including genetics, gender, age, obesity, hor-mones, pregnancy, and occupation. Sclerotheraphy is commonly used to treat small varicose veins. Medium-sized and large varicose veins can be removed by a surgical procedure called Stab avulsion or phlebectomy. EVLT is a new alternative surgical method for varicose veins. Patients & Methods: Using 980nm and 940nm diode laser with a 600micron bare-tipped fiber endoluminally under ultrasound and Doppler monitoring, we treated 43 patients in Noor Vein Clinic, Tehran, Iran. Results: The procedure was well tolerated by all patients with just a local anesthesia. No major complications were encountered. We noticed that 980nm and 940nm are the perfect wave lengths causing less post-operational discomfort for patients with enhanced recovery time due to fewer traumas to the adjacent tissues. One small size skin burn and local paresthesia were observed. Conclusion: We concluded that EVLT with diode laser is a safe, fast, and effective method with low recurrence rate.

  16. Functionalizing Designer DNA Crystals

    Science.gov (United States)

    Chandrasekaran, Arun Richard

    Three-dimensional crystals have been self-assembled from a DNA tensegrity triangle via sticky end interaction. The tensegrity triangle is a rigid DNA motif containing three double helical edges connected pair-wise by three four-arm junctions. The symmetric triangle contains 3 unique strands combined in a 3:3:1 ratio: 3 crossover, 3 helical and 1 central. The length of the sticky end reported previously was two nucleotides (nt) (GA:TC) and the motif with 2-helical turns of DNA per edge diffracted to 4.9 A at beam line NSLS-X25 and to 4 A at beam line ID19 at APS. The purpose of these self-assembled DNA crystals is that they can be used as a framework for hosting external guests for use in crystallographic structure solving or the periodic positioning of molecules for nanoelectronics. This thesis describes strategies to improve the resolution and to incorporate guests into the 3D lattice. The first chapter describes the effect of varying sticky end lengths and the influence of 5'-phosphate addition on crystal formation and resolution. X-ray diffraction data from beam line NSLS-X25 revealed that the crystal resolution for 1-nt (G:C) sticky end was 3.4 A. Motifs with every possible combination of 1-nt and 2-nt sticky-ended phosphorylated strands were crystallized and X-ray data were collected. The position of the 5'-phosphate on either the crossover (strand 1), helical (strand 2), or central strand (3) had an impact on the resolution of the self-assembled crystals with the 1-nt 1P-2-3 system diffracting to 2.62 A at APS and 3.1 A at NSLS-X25. The second chapter describes the sequence-specific recognition of DNA motifs with triplex-forming oligonucleotides (TFOs). This study examined the feasibility of using TFOs to bind to specific locations within a 3-turn DNA tensegrity triangle motif. The TFO 5'-TTCTTTCTTCTCT was used to target the tensegrity motif containing an appropriately embedded oligopurine.oligopyrimidine binding site. As triplex formation involving cytidine

  17. Fractional decay of quantum dots in real photonic crystals

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Koenderink, A. Femius; Lodahl, Peter;

    2008-01-01

    We show that fractional decay may be observable in experiments using quantum dots and photonic crystals with parameters that are currently achievable. We focus on the case of inverse opal photonic crystals and locate the position in the crystal where the effect is most pronounced. Furthermore, we...

  18. Immigrants' location preferences

    DEFF Research Database (Denmark)

    Damm, Anna Piil

    This paper exploits a spatial dispersal policy for refugee immigrants to estimate the importance of local and regional factors for refugees' location preferences. The main results of a mixed proportional hazard competing risks model are that placed refugees react to high regional unemployment...... and lack of a local immigrant population by migrating to large municipalities. Lack of local fellow countrymen, however, increases the exit rate to medium-sized as well as large municipalities. This finding is likely to be a result of the dispersal policy. Finally, refugees react strongly to assignment...

  19. Complications of radiofrequency ablation for liver cancer in high-risk locations and their prevention

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    ZHANG Junchao

    2017-05-01

    Full Text Available Radiofrequency ablation (RFA is one of the most important methods for the treatment of liver cancer and has the advantages of small trauma, simple operation, and repeatability. However, for tumors in high-risk locations within 5 mm of the first and second branches of the hepatic portal vein, near the hepatic vein, the inferior vena cava, or the gallbladder, within 5 mm of the intestinal tract, under the Glisson’s capsule, and in the diaphragm, RFA has the issues of a low complete ablation rate, a high local recurrence rate, and serious complications. This article introduces the complications of RFA for liver cancer in high-risk locations and their prevention and points out that with the promotion of individualized and standardized RFA, liver cancer in these high-risk locations is no longer a contradiction for RFA.

  20. Epithermal mercury-antimony and gold-bearing vein lodes of southwestern Alaska

    Science.gov (United States)

    Gray, John E.; Gent, Carol A.; Snee, Lawrence W.; Wilson, Frederic H.; Goldfarb, Richard J.; Miller, Lance D.

    1997-01-01

    Epithermal mineral deposits and occurrences of southwestern Alaska consist of Hg-Sb and gold- and sulfide-bearing vein lodes. Numerous Hg-Sb lodes are located throughout a region measuring several tens of thousands of square kilometers in and surrounding the Kuskokwim River basin in southwestern Alaska. The Hg-Sb lodes are hosted in sedimentary rocks of the Cretaceous Kuskokwim Group, the Triassic to Cretaceous Gemuk Group, and the Paleozoic Holitna Group, as well as in Late Cretaceous and early Tertiary mafic to felsic intrusive rocks. Mineralized Hg-Sb vein and vein breccia lodes are found in the sedimentary or igneous rocks or at their contacts. The minerology of the Hg-Sb lodes is dominated by cinnabar and stibnite, with subordinate realgar, orpiment, and native mercury, pyrite, gold, and hematite, as well as solid and liquid hydrocarbons; quartz, carbonate, limonite, dickite, and sercite are alteration gangue minerals. The largest mercury mine in Alaska, Red Devil, produced about 36,000 flasks of mercury, but the Hg-Sb lodes of southwestern Alaska generally consist of small, discontinuous veins that rarely exceed a few meters in width and a few tens of meters in strike length. The Hg-Sb lodes generally contain about 1 to 5 percent Hg and less than 1 percent Sb and As but are generally poor in base emtals and precious metals. Anomalous concentrations of gold in some lodes, however, suggest that gold deposits may be present in higher temperature environments below some of the Hg-Sb lodes.The formation of the Hg-Sb lodes is closely correlated with igneous activity of a Late Cretaceous and early tertiary magmatic arc in southwestern Alaska. Geologic and geochemical characteristics of the Hg-Sb lodes suggest that ore fluids were generated in local sedimentary rocks as they were intruded by magmas. These intrusions provided the heat to initiate dehydration reactions and expel fluids from hydrous minerals and formational waters in the sedimentary rocks, causing