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  • 201.
    Palhagen, Sven E
    et al.
    Karolinska University.
    Ekberg, Stefan
    Linköping University, Department of Medicine and Health Sciences, Radiation Physics . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Walinder, Jan
    University of Gothenburg.
    Granerus, Ann-Kathrine
    Linköping University, Department of Clinical and Experimental Medicine, Geriatric . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Geriatric Medicine.
    Granerus, Göran
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    HMPAO SPECT in Parkinsons disease (PD) with major depression (MD) before and after antidepressant treatment2009In: JOURNAL OF NEUROLOGY, ISSN 0340-5354, Vol. 256, no 9, p. 1510-1518Article in journal (Refereed)
    Abstract [en]

    Previously we suggested that major depression (MD) in Parkinsons disease (PD) could be an indication of a more advanced and widespread neurodegenerative process, as PD symptoms were more severe in those with depression. We also found a different antidepressant response with SSRI medication in PD patients with depression compared to depressed patients without PD. This indicates diverse underlying pathophysiological mechanisms. Investigations using single-photon emission computed tomography (SPECT), measuring regional cerebral blood flow (rCBF), may contribute to enlighten the neurobiological substrates linked to depressive symptoms. SPECT was performed in order to compare rCBF in MD patients with and without PD. The study included 11 MD patients with PD, 14 nondepressed PD patients and 12 MD patients without PD. All patients were followed for 12 weeks with repeated evaluation of depressive as well as PD symptoms. Anti-Parkinsonian treatment remained unchanged during the study. Antidepressant treatment with SSRI (citalopram) was given to all patients with MD. SPECT was performed before and after 12 weeks of antidepressant treatment. rCBF was found to differ between PD patients with and without MD, as well as between MD patients with and without PD, both at baseline and concerning the response to treatment with SSRI (citalopram). In patients with PD the rCBF was found to be decreased in preoccipital and occipital regions, a finding more common when PD was combined with MD. In summary, larger cortical areas were found to be involved in depressed PD patients, both with hyperactivity (reciprocal to basal degeneration in PD and maybe dopaminergic treatment) and with hypoactivity (probably due to organic lesions leading to hypoperfusion). These observations support our hypothesis that PD combined with MD is an expression of a more advanced and widespread neurodegenerative disorder.

  • 202.
    Persson, Anders
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Jackowski, Christian
    Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Engström, Elias
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Advances of dual source, dual-energy imaging in postmortem CT2008In: European Journal of Radiology, ISSN 0720-048X, E-ISSN 1872-7727, Vol. 68, no 3, p. 446-455Article in journal (Refereed)
    Abstract [en]

    This paper focuses on the use of multi-detector row dual-energy computed tomography (DECT) in the evaluation of postmortal examinations. The use of dual energy moves postmortem CT to an entirely new dimension of diagnostic sensitivity where contrast in the image is not merely limited to X-ray attenuation differences, but may include elements of functional and tissue characterization. This additional information may be used to improve the benefit postmortem imaging can provide to supplement and simplify the conventional autopsy. © 2008 Elsevier Ireland Ltd. All rights reserved.

  • 203.
    Petersson, Sven
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Dyverfeldt, Petter
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Gårdhagen, Roland
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Karlsson, Matts
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Ebbers, Tino
    Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Simulation of phase contrast MRI of turbulent flow2010In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 64, no 4, p. 1039-1046Article in journal (Refereed)
    Abstract [en]

    Phase contrast MRI is a powerful tool for the assessment of blood flow. However, especially in the highly complex and turbulent flow that accompanies many cardiovascular diseases, phase contrast MRI may suffer from artifacts. Simulation of phase contrast MRI of turbulent flow could increase our understanding of phase contrast MRI artifacts in turbulent flows and facilitate the development of phase contrast MRI methods for the assessment of turbulent blood flow. We present a method for the simulation of phase contrast MRI measurements of turbulent flow. The method uses an Eulerian-Lagrangian approach, in which spin particle trajectories are computed from time-resolved large eddy simulations. The Bloch equations are solved for each spin for a frame of reference moving along the spins trajectory. The method was validated by comparison with phase contrast MRI measurements of velocity and intravoxel velocity standard deviation (IVSD) on a flow phantom consisting of a straight rigid pipe with a stenosis. Turbulence related artifacts, such as signal drop and ghosting, could be recognized in the measurements as well as in the simulations. The velocity and the IVSD obtained from the magnitude of the phase contrast MRI simulations agreed well with the measurements.

  • 204.
    Petersson, Sven
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Dyverfeldt, Petter
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Sigfridsson, Andreas
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Lantz, Jonas
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Carlhäll, Carl-Johan
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Quantification of Stenotic Flow Using Spiral 3D Phase-Contrast MRI2013Manuscript (preprint) (Other academic)
    Abstract [en]

    Purpose: To evaluate the feasibility of spiral 3D phase contrast MRI for the assessment of velocity, volume flow rate, peak velocity and turbulent kinetic energy in stenotic flow.

    Materials and Methods: A-stack-of-spirals 3D phase contrast MRI sequence was evaluated in-vitro against a conventional Cartesian sequence. Measurements were made in a flow phantom with a 75% stenosis. Both spiral and Cartesian imaging were performed using different scan orientations and flow rates. Volume flow rate, peak velocity and turbulent kinetic energy (TKE) were computed for both methods. For further validation, the estimated TKE was compared to computational fluid dynamics (CFD) data.

    Results: The volume flow rate, peak velocity and TKE obtained with spiral 4D flow MRI agreed well with Cartesian data and CFD data. As expected, the short echo time of the spiral sequence resulted in less prominent displacement artifacts compared to the Cartesian sequence. However, both spiral and Cartesian flow rate estimates were sensitive to displacement when the flow was oblique to the encoding directions.

    Conclusion: Spiral 3D phase contrast MRI appears favorable for the assessment of stenotic flow. The spiral sequence was more than three times faster and less sensitive to displacement artifacts when compared to a conventional Cartesian sequence.

  • 205.
    Peterzén, Bengt
    et al.
    Linköping University, Department of Medicine and Health Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Granfeldt, Hans
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Lönn, Urban
    Carnstam, Bo
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Dahlström, Ulf
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences.
    Ruthberg, Hans
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Casimir Ahn, Henrik
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Management of patients with end-stage heart disease treated with an implantable left ventricular assist device in a nontransplanting center2000In: Journal of cardiothoracic and vascular anesthesia, ISSN 1053-0770, Vol. 14, no 4, p. 438-443Article in journal (Refereed)
    Abstract [en]

    Objective: To describe the setup of a left ventricular assist device (LVAD) program in a nontransplanting center.

    Design: A prospective study from February 1993 to June 1999.

    Setting: A university hospital.

    Participants: Ten patients, 6 men, with a mean age of 44 years (range 16 to 63 years) and with end-stage heart failure resulting from dilated cardiomyopathy (n = 7) or ischemic heart disease (n = 3).

    Interventions: The patients received the TCI (Thermo Cardiosystems Inc, Woburn, MA) Heart Mate implantable assist device. Five patients had a pneumatic device, and 5 had an electric device. All except 1 patient with an electric device had the pump for an extended period.

    Measurements and Main Results: Median time on the ventilator was 6.2 days, and median time in the ICU was 14 days. Significant hemodynamic improvement was observed by echocardiography and invasive monitoring. Milrinone and epinephrine supplemented by prostaglandin E1 were the most commonly used drugs to avoid right-sided heart failure. Nine patients were transplanted after pump therapy of 241 days (median) (range, 56 to 873 days). One patient died because of endovascular infection and septicemia. Infectious complications were frequent, especially when the pump time was extended.

    Conclusions: The introduction of an LVAD program in a nontransplanting center can be achieved with good results. Intense collaboration with a transplant center is mandatory. The complication rate increased when treatment times were extended.

  • 206.
    Peterzén, Bengt
    et al.
    Linköping University, Department of Medicine and Health Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Lönn, Urban
    Jansson, Kjell
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Ruthberg, Hans
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Casimir Ahn, Hans
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Long-term follow-up of patients treated with an implantable left ventricular assist device as an extended bridge to heart transplantation2002In: The Journal of Heart and Lung Transplantation, ISSN 1053-2498, Vol. 21, no 5, p. 604-607Article in journal (Refereed)
    Abstract [en]

    Four patients were given the TCI implantable left ventricular assist device as a bridge to heart transplantation. The median treatment time was 541 days (range 462 to 873 days), with a total of 2,417 treatment days. The patients were followed with exercise tests and echocardiography 3 to 18 months after implantation. An invasive method was used for quantification of inflow valve incompetence.

  • 207. Piepsz, A
    et al.
    Blaufox, M D
    Gordon, I
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Majd, M
    O'Reilly, PO
    Rosenberg, A R
    Rossleigh, M A
    Sixt, R
    Concensus on renal cortical scintigraphy in children with urinary tract infection.1999In: Seminars in nuclear medicine, ISSN 0001-2998, E-ISSN 1558-4623, Vol. 29, p. 160-174Article in journal (Refereed)
  • 208.
    Pislaru, Cristina
    et al.
    Departments of Cardiology University of Leuven, Leuven, Belgium.
    D'hooge, Jan
    Department of Electrical Engineering, Medical Image Computing, University of Leuven, Leuven, Belgium.
    Pislaru, Sorin V
    Departments of Cardiology University of Leuven, Leuven, Belgium.
    Brandt, Einar
    Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Cipic, Roberg
    Department of Cardiology, Klinikum Innenstadt, University of Munich, Munich, Germany.
    Angermann, Christiane E
    Department of Cardiology, Klinikum Innenstadt, University of Munich, Munich, Germany.
    Van de Werf, Frans
    Departments of Cardiology University of Leuven, Leuven, Belgium.
    Bijnens, Bart
    Departments of Cardiology University of Leuven, Leuven, Belgium.
    Herregods, Marie-Christine
    Departments of Cardiology University of Leuven, Leuven, Belgium.
    Sutherland, George R
    Departments of Cardiology University of Leuven, Leuven, Belgium.
    Is there a change in myocardial nonlinearity during the cardiac cycle?2001In: Ultrasound in Medicine and Biology, ISSN 0301-5629, E-ISSN 1879-291X, Vol. 27, no 3, p. 389-398Article in journal (Refereed)
    Abstract [en]

    The distortion of a sound wave during propagation results in progressive transfer of the energy from fundamental to higher harmonics, and is dependent on the nonlinearity of the medium. We studied if relative changes in acoustical nonlinearity occur in healthy myocardium during the cardiac cycle. Radiofrequency data were acquired from transthoracic echocardiography (2.5 and 3.5 MHz), parasternal long axis view, from five dogs and nine healthy volunteers. Integrated backscatter was calculated after filtering for fundamental (FIB) and second harmonic frequencies (SHIB), from a region in the posterior myocardial wall. The results suggest that there is little difference between the SHIB and FIB, although there were large variations between individuals. The maximal changes in nonlinearity, as estimated by SHIB/FIB ratio, mostly occurred during systole. SHIB presented similar cyclic variation with FIB (p = NS). Further studies are necessary to separate the role of myocardial nonlinearity, attenuation, propagating distance, or acoustical properties of the blood. The results are important in further tissue characterization studies employing second harmonic data.

  • 209. Prignent, Alain
    et al.
    Cosgriff, Philip
    Gates, Gary F
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Fine, Eugene J
    Itoh, Kazua
    Peters, Mike
    Piepsz, Amy
    Rehling, Michael
    Rutland, Michael
    Taylor, Andrew Jr
    Concensus report on quality control of quantitative measurments of renal function obtained from the renogram: Internaltional concensus committee from the scientific committee of radionuclides in nephrourology.1999In: Seminars in nuclear medicine, ISSN 0001-2998, E-ISSN 1558-4623, Vol. 29, p. 146-159Article in journal (Refereed)
  • 210.
    Renner, Johan
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, The Institute of Technology.
    Gårdhagen, Roland
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, The Institute of Technology.
    Ebbers, Tino
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Heiberg, Einar
    Department of Clinical Physiology, Lund University Hospital, Sweden.
    Länne, Toste
    Linköping University, Department of Medicine and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Karlsson, Matts
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, The Institute of Technology.
    A method for subject specific estimation of aortic wall shear stress2009In: WSEAS Transactions on Biology and Biomedicine, ISSN 1109-9518, Vol. 6, no 3, p. 49-57Article in journal (Refereed)
    Abstract [en]

    Wall shear stress (WSS) distribution in the human aorta is a highly interesting hemodynamic factor for atherosclerosis development. We present a magnetic resonance imaging (MRI) and computational fluid dynamics (CFD) based subject specific WSS estimation method and demonstrate it on a group of nine healthy volunteers (males age 23.6 ± 1.3 years). In all nine subjects, the aortic blood flow was simulated in a subject specific way, where the 3D segmented geometries and inflow profiles were obtained using MRI. No parameter settings were tailored using data from the nine subjects. Validation was performed by comparing CFD gained velocity with magnetic resonance imaging (MRI) velocity measurements. CFD and MRI velocity profiles were comparable, but the temporal variations of the differences during the cardiac cycle were significant. Spatio-temporal analyzes on the WSS distribution showed a strong subject specific influence. Subject specific models are decisive to estimate WSS distribution.

  • 211.
    Ressner, Marcus
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Brodin, Lars-Åke
    The Royal Institute of Technology, Stockholm, Sweden.
    Jansson, Tomas
    Lund Institute of Technology, Lund, Sweden.
    Hoff, Lars
    Vestfold University College, Noway.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Effects of ultrasound contrast agents on doppler tissue velocity estimation2006In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 19, no 2, p. 154-164Article in journal (Refereed)
    Abstract [en]

    The combination of Doppler tissue imaging and myocardial contrast echocardiography has the potential to provide information about motion and perfusion of the myocardium in a single examination. The purpose of this study was to establish how the presence of ultrasound contrast agent (UCA) affects measurements of Doppler tissue velocities in vivo and in vitro. We performed echocardiography in 12 patients with ischemic heart disease before and immediately after a slow intravenous infusion of the UCA Optison, using color Doppler tissue imaging to examine the effect of contrast agents in vivo. The myocardial peak systolic velocities and their integrals were analyzed in digitally stored cineloops before and after contrast administration. To distinguish between methodologic and physiologic factors affecting the measurement of tissue velocity in vitro, experiments with a rotating disk and a flow cone phantom were also carried out for the 3 contrast agents: Optison, Sonovue, and Sonazoid. In vivo results show that the values for peak systolic velocity increased by about 10% during contrast infusion, from mean 5.2 ± 1.8 to 5.7 ± 2.3 cm/s (P = .02, 95% confidence interval 2%-16%). The increase in myocardial peak systolic velocities was verified in experimental models in which the UCA increased the estimated mean velocity in the order of 5% to 20% for the motion interval of 5 to 7 cm/s, corresponding to the myocardial velocities studied in vivo. The response was similar for all 3 contrast agents and was not affected by moderate variations in concentration of the agent. We have shown that the presence UCA will affect Doppler tissue measurements in vivo and in vitro. The observed bias is presumed to be an effect of harmonic signal contribution from rupturing contrast agent microbubbles and does not indicate biologic or physiologic effects. Copyright 2006 by the American Society of Echocardiography.

  • 212.
    Ressner, Marcus
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Brodin, Lars-Åke
    Jansson, Tomas
    Dept of Electrical Measurements Lund University.
    Hoff, Lars
    Faculty of Science and Engineering Vestfold University, Horten, Norge.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Effekter av ultraljudskontrast vid hastighetsestimering med vävnadsdoppler2005In: Svenska Läkaresällskapets Riksstämma 2005,2005, 2005Conference paper (Other academic)
  • 213.
    Ressner, Marcus
    et al.
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Brodin, L-Å.
    Jansson, Tomas
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Janerot-Sjöberg, Birgitta
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    How Ultrasound Contrast Agents effects Doppler Tissue Velocity Estimation2006Conference paper (Other academic)
  • 214.
    Ressner, Marcus
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Jansson, Tomas
    Lund University.
    Cedefamn, Jonny
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Janerot Sjöberg, Birgitta
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Contrast Biases the Autocorrelation Phase Shift Estimation in Doppler Tissue Imaging2009In: Ultrasound in Medicine and Biology, ISSN 0301-5629, E-ISSN 1879-291X, Vol. 35, no 3, p. 447-457Article in journal (Refereed)
    Abstract [en]

    Quantitative assessment of regional myocardial function at rest and during stress with Doppler tissue imaging (DTI) plays an important role in daily routine echocardiography. However, reliable visual analysis is largely dependent on image quality and adequate border delineation, which still remains a challenge in a significant number of patients. In this respect, an ultrasound contrast agent (UCA) is often used to improve visualization in patients with suboptimal image quality. The knowledge of how DTI measurements will be affected by UCA present in the tissue is therefore of significant importance for an accurate interpretation of local myocardial motion. The aim of this paper was to investigate how signal contribution from UCA and nonlinear wave propagation influence the performance of the autocorrelation phase shift estimator used for DTI applications. Our results are based on model experiments with a clinical 2-D grayscale scanner and computational simulations or the DTI velocity estimator for synthetically-derived pulses, simulated bubble echoes and experimentally-sampled RF data of transmitted pulses and backscattered contrast echoes. The results show that destruction of UCA present in the tissue will give rise to an apparent bidirectional velocity bias of individual velocity estimates, but that spatial averaging of individual velocity measurements within a region-of-interest will result in a negative bias (away from the transducer) of the estimated mean or mean peak velocity. The UCA destruction will also have a significant impact on the measured integrated mean velocity over time, i.e., displacement. To achieve improved visualization with UCA during DTI-examinations, we either recommend that it is performed at low acoustic powers, mechanical index <= 0.3, thereby minimizing the effects from bubble rupture, or that each Doppler pulse package is preceded by a destruction burst similar to "Flash imaging" to clear the target area of contrast microbubbles.

  • 215.
    Ressner, Marcus
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Kvikliene, Adriana
    Kaunas University of Technology.
    Hoff, Lars
    Westfold University College.
    Jurkonis, Rytis
    Kaunas University of Technology.
    Jansson, Tomas
    Lunds universitet.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lukosevicius, Arunas
    Kaunas University of Technology.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Backscattered ultrasound from contrast microbubbles: effects of tissue and bubble interaction2004In: EMBS,2004, San Francisco: IEEE , 2004, p. 849-Conference paper (Refereed)
  • 216.
    Ressner, Marcus
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Kvikliene, Adriana
    Inst of Biomedical Engineering Kaunas University of Technology,Lithuania.
    Hoff, Lars
    Faculty ofScience and Engineering Vestfold University, Horten, Norge.
    Jurkonis, Rytis
    Inst of Biomedical Engineering Kaunas University of Technology, Lithuania.
    Jansson, Tomas
    Dept of Electrical Measurements Lunds universitet.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lukosevicius, Arunas
    Inst of Biomedical Engineering Kaunas University of Technology, Lithuania.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Ultrasound contrast for perfusion studies2005In: Nordic Baltic Conference Biomedical Engineering and Medical Physics,2005, Umeå: IFMBE , 2005, p. 107-Conference paper (Refereed)
  • 217.
    Ressner, Marcus
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Kvikliene, Adriana
    Kaunas University of Technology .
    Hoff, Lars
    Vestfold University, Horten Norge.
    Jurkonis, Rytis
    Kaunas University of Technology .
    Jansson, Tomas
    Lund University .
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lukosevicius, Arunas
    Kaunas University of Technology .
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Ultrasound contrast microbubbles: simulations and in vitro experiments2005In: EMBEC05,2005, Prag: IFMBE , 2005Conference paper (Refereed)
  • 218. Richter, A
    et al.
    Cederholm, I
    Mucciano, C
    Jonasson, L
    Larsson, LE
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Longterm home treatment with thoracic epidural analgesia in refractory angina2001In: Abstract at 4th International congress on coronary artery disease, Prague 2001,2001, 2001Conference paper (Refereed)
  • 219.
    Ricther, Arina
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Cederholm, Ingemar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Jonasson, Lena
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Mucchiano, Carlo
    Smärtkliniken Eksjö.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Uchto, Michael
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Effect of thoracic epidural analgesia on refractory angina pectoris: Long-term home self-treatment2002In: Journal of Cardiothoracic and Vascular Anesthesia, ISSN 1053-0770, E-ISSN 1532-8422, Vol. 16, no 6, p. 679-684Article in journal (Refereed)
    Abstract [en]

    Objectives: To evaluate the effects of long-term home self-treatment with thoracic epidural analgesia (TEA) on angina, quality of life, and safety. Design: Prospective consecutive pilot study. Setting: Department of Cardiology, Heart Center, Link÷ping University Hospital. Participants: Between January 1998 and January 2000, 37 consecutive patients with refractory angina began treatment with TEA, using a subcutaneously tunnelled epidural catheter. Interventions: The patients were trained to provide self-treatment at home with intermittent injections of bupivacaine. Data were collected until January 2001, and the follow-up for each patient was 1 to 3 years. Measurements and Main Results: All but 1 of the patients improved symptomatically. The improvement was maintained throughout the treatment period (4 days to 3 years). The Canadian Cardiovascular Society angina class decreased from 3.6 to 1.7, frequency of anginal attacks decreased from 46 to 7 a week, nitroglycerin intake decreased from 32 to 5 a week, and the overall self-rated quality of life assessed by visual analog scale increased from 24 to 76 (all p < 0.001). No serious catheter-related complications occurred, however, 51% of the catheters became displaced and a new one had to be inserted during the study. Conclusion: Long-term self-administered home treatment with TEA seems to be an effective and safe adjuvant treatment for patients with refractory angina. It produces symptomatic relief of angina and improves the quality of life.

  • 220.
    Rosendahl, Lene
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Ahlander, Britt-Marie
    Ryhov County Hospital.
    Bjorklund, Per-Gunnar
    Ryhov County Hospital.
    Blomstrand, Peter
    Ryhov County Hospital.
    Brudin, Lars
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Image quality and myocardial scar size determined with magnetic resonance imaging in patients with permanent atrial fibrillation: a comparison of two imaging protocols2010In: CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, ISSN 1475-0961, Vol. 30, no 2, p. 122-129Article in journal (Refereed)
    Abstract [en]

    Pandgt;Background: Magnetic resonance imaging (MRI) of the heart generally requires breath holding and a regular rhythm. Single shot 2D steady-state free precession (SS_SSFP) is a fast sequence insensitive to arrhythmia as well as breath holding. Our purpose was to determine image quality, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios and infarct size with a fast single shot and a standard segmented MRI sequence in patients with permanent atrial fibrillation and chronic myocardial infarction. Methods: Twenty patients with chronic myocardial infarction and ongoing atrial fibrillation were examined with inversion recovery SS_SSFP and segmented inversion recovery 2D fast gradient echo (IR_FGRE). Image quality was assessed in four categories: delineation of infarcted and non-infarcted myocardium, occurrence of artefacts and overall image quality. SNR and CNR were calculated. Myocardial volume (ml) and infarct size, expressed as volume (ml) and extent (%), were calculated, and the methodological error was assessed. Results: SS_SSFP had significantly better quality scores in all categories (P = 0 center dot 037, P = 0 center dot 014, P = 0 center dot 021, P = 0 center dot 03). SNRinfarct and SNRblood were significantly better for IR_FGRE than for SS_SSFP (P = 0 center dot 048, P = 0 center dot 018). No significant difference was found in SNRmyocardium and CNR. The myocardial volume was significantly larger with SS_SSFP (170 center dot 7 versus 159 center dot 2 ml, P andlt; 0 center dot 001), but no significant difference was found in infarct volume and infarct extent. Conclusion: SS_SSFP displayed significantly better image quality than IR_FGRE. The infarct size and the error in its determination were equal for both sequences, and the examination time was shorter with SS_SSFP.

  • 221.
    Rosendahl, Lene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Blomstrand, Peter
    Department of Clinical Physiology, Ryhov County Hospital, Jönköping, Sweden.
    Brudin, Lars
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Tödt, Tim
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Engvall, Jan E
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Longitudinal peak strain detects a smaller risk area than visual assessment of wall motion in acute myocardial infarction2010In: Cardiovascular ultrasound, ISSN 1476-7120, Vol. 8, no 2, p. 1-12Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Opening of an occluded infarct related artery reduces infarct size and improves survival in acute ST-elevation myocardial infarction (STEMI). In this study we performed tissue Doppler analysis (peak strain, displacement, mitral annular movement (MAM)) and compared with visual assessment for the study of the correlation of measurements of global, regional and segmental function with final infarct size and transmurality. In addition, myocardial risk area was determined and a prediction sought for the development of infarct transmurality >or=50%.

    METHODS: Twenty six patients with STEMI submitted for primary percutaneous coronary intervention (PCI) were examined with echocardiography on the catheterization table. Four to eight weeks later repeat echocardiography was performed for reassessment of function and magnetic resonance imaging for the determination of final infarct size and transmurality.

    RESULTS: On a global level, wall motion score index (WMSI), ejection fraction (EF), strain, and displacement all showed significant differences (p or=50%, but strain added no significant information to that obtained with WMSI in a logistic regression analysis.

    CONCLUSIONS: In patients with acute STEMI, WMSI, EF, strain, and displacement showed significant changes between the pre- and post PCI exam. In a ROC-analysis, strain had 64% sensitivity at 80% specificity and WMSI around 90% sensitivity at 80% specificity for the detection of scar with transmurality >or=50% at follow-up.

  • 222.
    Rosendahl, Lene
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology .
    Blomstrand, Peter
    Ryhovs sjukhus Jönköping.
    Heiberg, Einar
    Lunds universitet Lund.
    Ohlsson, Jan
    Ryhovs sjukhus Jönköping.
    Björklund, Per-Gunnar
    Ryhovs sjukhus Jönköping.
    Ahlander, Britt-Marie
    Ryhovs sjukhus Jönköping.
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Computer-assisted calculation of myocardial infarct size shortens the evaluation time of contrast-enhanced cardiac MRI2008In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 28, no 1Article in journal (Refereed)
    Abstract [en]

    Background: Delayed enhancement magnetic resonance imaging depicts scar in the left ventricle which can be quantitatively measured. Manual segmentation and scar determination is time consuming. The purpose of this study was to evaluate a software for infarct quantification, to compare with manual scar determination, and to measure the time saved. Methods: Delayed enhancement magnetic resonance imaging was performed in 40 patients where myocardial perfusion single photon emission computed tomography imaging showed irreversible uptake reduction suggesting a myocardial scar. After segmentation, the semi-automatic software was applied. A scar area was displayed, which could be corrected and compared with manual delineation. The different time steps were recorded with both methods. Results: The software shortened the average evaluation time by 12.4min per cardiac exam, compared with manual delineation. There was good correlation of myocardial volume, infarct volume and infarct percentage (%) between the two methods, r = 0.95, r = 0.92 and r = 0.91 respectively. Conclusions: A computer software for myocardial volume and infarct size determination cut the evaluation time by more than 50% compared with manual assessment, with maintained clinical accuracy. © 2007 The Authors Journal compilation 2007 Blackwell Publishing Ltd.

  • 223.
    Rosendahl, Lene
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology .
    Blomstrand, Peter
    County Hospital Ryhov.
    Ohlsson, Jan L
    County Hospital Ryhov.
    Björklund, Per-Gunnar
    County Hospital Ryhov.
    Ahlander, Britt-Marie
    County Hospital Ryhov.
    Starck, Sven-Åke
    County Hospital Ryhov.
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Late gadolinium uptake demonstrated with magnetic resonance in patients where automated PERFIT analysis of myocardial SPECT suggests irreversible perfusion defect.2008In: BMC Medical Imaging, ISSN 1471-2342, E-ISSN 1471-2342, Vol. 8Article in journal (Refereed)
  • 224.
    Samuelsson, Kersti
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Rehabilitation Medicine. Östergötlands Läns Landsting, Reconstruction Centre, Department of Rehabilitation Medicine UHL.
    Tropp, Hans
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Orthopaedics and Sports Medicine. Östergötlands Läns Landsting, Orthopaedic Centre, Department of Orthopaedics Linköping.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Gerdle, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Rehabilitation Medicine. Östergötlands Läns Landsting, Centre for Medicine, Pain and Rehabilitation Centre.
    The effect of rear-wheel position on seating ergonomics and mobility efficiency in wheelchair users with spinal cord injuries: A pilot study2004In: Journal of rehabilitation research and development, ISSN 0748-7711, E-ISSN 1938-1352, Vol. 41, no 1, p. 65-74Article in journal (Refereed)
    Abstract [en]

    This study analyzed the effect of rear-wheel position on seating comfort and mobility efficiency. Twelve randomly selected paraplegic wheelchair users participated in the study. Wheelchairs were tested in two rear-wheel positions while the users operated the wheelchair on a treadmill and while they worked on a computer. Propulsion efficiency, seating comfort, and propulsion qualities were registered at different loads during the treadmill session. During the computer session, pelvic position, estimated seating comfort, and estimated activity performance were measured. The change in rear-wheel position affected wheelchair ergonomics with respect to weight distribution (p < 0.0001) and seat inclination angle (position I = 5° and position II = 12°). These changes had a significant effect on push frequency (p < 0.05) and stroke angle (p < 0.05) during wheelchair propulsion. We found no consistent effect on mechanical efficiency, estimated exertion, breathlessness, seating comfort, estimated propulsion qualities, pelvic position, or activity performance.

  • 225.
    Scheike, Morten
    et al.
    Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Nilsson, Staffan
    Linköping University, Department of Department of Health and Society, General Practice. Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Clinical and Experimental Medicine, Plastic Surgery, Hand Surgery and Burns. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Exercise testing and myocardial perfusion scintigraphy in primary care patients with chest pain of new onset2007In: Scandinavian Journal of Primary Health Care, ISSN 0281-3432, E-ISSN 1502-7724, Vol. 25, no 2, p. 117-122Article in journal (Refereed)
    Abstract [en]

    Objective: To analyse the outcome of exercise testing and myocardial perfusion scintigraphy (MPS) in primary care patients with chest pain of new onset.

    Design: Prospective, observational. Patients aged 20-79 years, consulting due to chest pain of new onset, were enrolled consecutively.

    Setting: Three primary care health centres in south-eastern Sweden.

    Patients: 191 patients where the possibility of stable ischaemic heart disease (IHD) could not be excluded by clinical examination alone.

    Main outcome measures: Exercise test results, when equivocal completed by MPS.

    Results: Exercise testing revealed IHD in 14 (7%) and no IHD in 134 (70%) of the cases. In 43 (23%) the exercise test results were equivocal. Thirty-nine of these patients underwent MPS, which showed IHD in 19 and no IHD in 20 cases. Among previously diagnosed cardiovascular disease and risk factors only atrial fibrillation in the male group showed a significant correlation to the outcome IHD.

    Conclusion: Exercise testing and MPS are both useful when investigating chest pain patients in primary care.

  • 226.
    Schmekel, Birgitta
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pharmacology.
    Malmström, M
    Venge, P
    Eosinophil cationic protein (ECP) in saliva: A new marker of disease activity in bronchial asthma2001In: Respiratory Medicine, ISSN 0954-6111, E-ISSN 1532-3064, Vol. 95, no 8, p. 670-675Article in journal (Refereed)
    Abstract [en]

    Eosinophil cells play a crucial role in the pathogenesis of asthma, and concentration of eosinophil cationic protein (ECP) in serum has been used to monitor activity of the disease. Our aim was to determine the feasibility and usefulness of measuring ECP in saliva and to use it as a marker of the disease. Thirty-eight patients with asthma and 16 healthy volunteers were included in this study. Repeatability of measurements of ECP in saliva was acceptable [intra-class correlation coefficients (Ri) = 0.74 and coefficients of repeatability (CR) = 0.37 in five healthy subjects]. Levels of ECP in saliva were higher in asthmatics than in volunteers (P < 0.01). There was a significant inverse association between a surrogate variable reflecting disease activity (i.e. change over a few weeks in dose of inhaled corticosteroid required by a change in clinical status of asthma) and a change over the same time period in salivary ECP in 19 patients with stable asthma (r = -0.64, P = 0.02). Our findings indicate that levels of salivary ECP are elevated in patients with asthma and associated with presumed activity of disease as recorded by alteration of taken dose of inhaled corticosteroid. ⌐ 2001 Harcourt Publishers Ltd.

  • 227.
    Schmekel, Birgitta
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hedenström, Hans
    Klinisk fysiologi Uppsala.
    Hedenstierna, Göran
    Klinisk fysiologi Uppsala.
    Deposition of Terbutaline in the large or small airways: a single-center pilot study of ventilation-perfusion distribution and airway tone2002In: Current Therapeutic Research: Clinical and Experimental, ISSN 0011-393X, E-ISSN 1879-0313, Vol. 63, p. 536-548Article in journal (Refereed)
  • 228.
    Schmekel, Birgitta
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Seveus, L
    Xu, S Y
    Venge, Per
    Human neutrophil lipocalin (HNL) and myeloperoxidase (MPO). Studies of lung lavage fluid and lung tissue2000In: Respiratory Medicine, ISSN 0954-6111, E-ISSN 1532-3064, Vol. 94, no 6, p. 564-568Article in journal (Refereed)
    Abstract [en]

    Myeloperoxidase (MPO) and human neutrophil lipocalin (HNL) are proteins which are stored in neutrophil granulocytes, in the primary and secondary granules, respectively. These granules or their contents of MPO and HNL are secreted upon activation of the cells, and measurement of these soluble markers in biological fluids, such as bronchoalveolar lavage (BAL), has been proposed to mirror the degree of neutrophil activity in the tissue. We conducted a BAL study in 10 healthy volunteers, with the aim to evaluate the intra-individual variability of the concentration of HNL and MPO recovered in sequential aspirations, during a time period when the concentrations of HNL and MPO in BAL fluids were considered to have equilibrated with those in the underlying tissues. The concentrations of HNL were less variable than those of MPO (coefficients of variability 0.33+/-0.07 vs. 0.92+/-0.28,P+/-0.01). Suggesting HNL to be a more useful marker of neutrophil activity within the airspace. The specificity of HNL as a selective index of neutrophil cells was confirmed by means of immunohistochemical staining of uninvolved lung tissue specimens obtained from patients referred to pulmonectomy due to carcinoma. While HNL was located only to intracellular spaces of neutrophils, MPO was in addition located to other cells as well. We speculate that the dynamic changes of pressure across the membranes and flow of solutes during a lavage process might mobilize particulate matter and adherent cells, some of which may be loaded with MPO, and that this may introduce larger variability in the recovery of MPO than of HNL. We conclude that using HNL as a soluble indicator of neutrophil presence is more feasible than using MPO.

  • 229.
    Selbing, Anders
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Obstetrics and gynecology. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics in Linköping.
    Anghagen, O
    Bylund, B
    Nelson, Nina
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Pediatrics. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Paediatrics in Linköping.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Velocity vector imaging to assess fetal myocardial function2007In: Ultrasound Obstet Gynecol.,2007, 2007Conference paper (Other academic)
    Abstract [en]

         

  • 230.
    Selskog, Pernilla
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Brandt, Einar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Wigström, Lars
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Karlsson, Matts
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Quantification and Visualization of myocardial strain-rate tensors from time-resolved 3D cine phase contrast MRI.2001In: Proc. Intl. Soc. Mag. Reson. Med.,2001, 2001, p. 1870-1870Conference paper (Refereed)
  • 231.
    Sigfridsson, Andreas
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Heiberg, Einar
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Wigström, Lars
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Tensor Field Visualisation using Adaptive Filtering of Noise Fields combined with Glyph Rendering2002In: IEEE Visualization 2002 Conference, IEEE , 2002, p. 371-378Conference paper (Refereed)
    Abstract [en]

    While many methods exist for visualising scalar and vector data, visualisation of tensor data is still troublesome. We present a method for visualising second order tensors in three dimensions using a hybrid between direct volume rendering and glyph rendering.

    An overview scalar field is created by using three-dimensional adaptive filtering of a scalar field containing noise. The filtering process is controlled by the tensor field to be visualised, creating patterns that characterise the tensor field. By combining direct volume rendering of the scalar field with standard glyph rendering methods for detailed tensor visualisation, a hybrid solution is created.

    A combined volume and glyph renderer was implemented and tested with both synthetic tensors and strain-rate tensors from the human heart muscle, calculated from phase contrast magnetic resonance image data. A comprehensible result could be obtained, giving both an overview of the tensor field as well as detailed information on individual tensors.

  • 232.
    Sigfridsson, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Escobar Kvitting, John-Peder
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Wigström, Lars
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    5D MRI - Cardiac and respiratory time-resolved volume imaging2004In: Proceedings of the annaual conference of the European Society for Magnetic Resonance in Medicine and Biology, 2004Conference paper (Refereed)
    Abstract [en]

    Respiratory motion is often a source of artifacts in cardiovascular imaging, but may also convey important physiological information. To improve our understanding

  • 233.
    Sigfridsson, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Escobar Kvitting, John-Peder
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Wigström, Lars
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Andersson, Mats
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Retrospective Respiratory Motion Compensation for Cardiac MRI2003Conference paper (Refereed)
    Abstract [en]

    Cardiac MRI is known to be degraded by respiratory motion. Short scans can be performed using breath-hold techniques, while coronary artery imaging commonly use navigator gated sequences, acquiring data in a known static respiration position.

  • 234.
    Sigfridsson, Andreas
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Escobar Kvitting, John-Peder
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Wigström, Lars
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    k-t2 BLAST: Exploiting spatiotemporal structure in simultaneous cardiac and respiratory resolved volume imaging2005Conference paper (Refereed)
    Abstract [en]

    Multidimensional imaging resolving both the cardiac and respiratory cycles simultaneously has the potential to describe important physiological interdependences between the heart and pulmonary processes. A fully five-dimensional acquisition with three spatial and two temporal dimensions is hampered, however, by the long acquisition time and low spatial resolution. A technique is proposed to reduce the scan time substantially by extending the k-t BLAST framework to two temporal dimensions. By sampling the k-t space sparsely in a lattice grid, the signal in the transform domain, x-f space, can be densely packed, exploiting the fact that large regions in the field of view have low temporal bandwidth. A volumetric online prospective triggering approach with full cardiac and respiratory cycle coverage was implemented. Retrospective temporal interpolation was used to refine the timing estimates for the center of k-space, which is sampled for all cardiac and respiratory time frames. This resulted in reduced reconstruction error compared with conventional k-t BLAST reconstruction. The k-t2 BLAST technique was evaluated by decimating a fully sampled five-dimensional data set, and feasibility was further demonstrated by performing sparsely sampled acquisitions. Compared to the fully sampled data, a fourfold improvement in spatial resolution was accomplished in approximately half the scan time.

  • 235.
    Sigfridsson, Andreas
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Estepar, R.
    E.T.S.I. Telecomunicaci´on, University of Valladolid, Spain.
    Wigström, Lars
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Alberola, C.
    E.T.S.I. Telecomunicaci´on, University of Valladolid, Spain.
    Westin, C-F.
    Brigham and Women’s Hospital, Harvard Medical School, Boston.
    Diffusion tensor visualization using random field correlation and volume rendering2003Conference paper (Refereed)
    Abstract [en]

    The visualization of diffusion tensor fields remains a challenging topic. A representation based on volume rendering of a scalar field is presented. The method uses the tensor to correlate a noise field in the direction of greater diffusivity while preserving the high frequency components of the noise field in transversal diffusion directions.

  • 236.
    Sigfridsson, Andreas
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Haraldsson, Henrik
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Knutsson, Hans
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Sakuma, Hajima
    Mie University, Japan.
    SNR evaluation of 32 channel cardiac coils in DENSE MRI at 1.5 and 3T2010In: ISMRM 2010, International Society for Magnetic Resonance in Medicine ( ISMRM ) , 2010Conference paper (Other academic)
  • 237.
    Sigfridsson, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Haraldsson, Henrik
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Ebbers, Tino
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Sakuma, Hajime
    Radiology, Mie University, Japan.
    In-vivo SNR in DENSE MRI: temporal and regional effects of field strength, receiver coil sensitivity, and flip angle strategies2011In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 29, no 2, p. 202-208Article in journal (Refereed)
    Abstract [en]

    Aim: The influences on the SNR of DENSE MRI of field strength, receiver coil sensitivity and choice of flip angle strategy have been previously investigated individually. In this study, all of these parameters have been investigated in the same setting, and a mutual comparison of their impact on SNR is presented.

    Materials and methods: Ten healthy volunteers were imaged in a 1.5T and a 3T MRI system, using standard 5 or 6 channel cardiac coils as well as 32 channel coils, with four different excitation patterns. Variation of spatial coil sensitivity was assessed by regional SNR analysis.

    Results: SNR ranging from 2.8 to 30.5 was found depending on the combination of excitation patterns, coil sensitivity and field strength. The SNR at 3T was 53 ± 26% higher than at 1.5T (p<0.001), whereas spatial differences of 59 ± 26% were found in the ventricle (p<0.001). 32 channel coils provided 52 ± 29% higher SNR compared to standard 5 or 6 channel coils (p<0.001). A fixed flip angle strategy provided an excess of 50% higher SNR in half of the imaged cardiac cycle compared to a sweeping flip angle strategy, and a single phase acquisition provided a six-fold increase of SNR compared to a cine acquisition.

    Conclusion: The effect of field strength and receiver coil sensitivity influences the SNR with the same order of magnitude, whereas flip angle strategy can have a larger effect on SNR. Thus, careful choice of imaging hardware in combination with adaptation of the acquisition protocol is crucial in order to realize sufficient SNR in DENSE MRI.

  • 238.
    Sigfridsson, Andreas
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Haraldsson, Henrik
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Knutsson, Hans
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Sakuma, Hajime
    Radiology, Mie University, Japan.
    Single Breath Hold Multiple Slice DENSE MRI2010In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 63, no 5, p. 1411-1414Article in journal (Refereed)
    Abstract [en]

    A method to acquire multiple displacement encoded slices within asingle breath hold is presented. Efficiency is improved overconventional Displacement ENcoding with Stimulated Echoes (DENSE) without compromising image quality by read-out of multiple slices inthe same cardiac cycle, thus utilizing the position encoded stimulatedecho available in the whole heart. The method was evaluated bycomparing strain values obtained using the proposed method to strainvalues obtained by conventional separate breath hold single-sliceDENSE acquisitions. Good agreement (Lagrangian E2 strainbias=0.000, 95% limits of agreement ±0.04,root-mean-square-difference 0.02 (9.4% of the mean end-systolic E2)) was found between the methods, indicating that the proposedmethod can replace a multiple breath hold acquisition. Eliminating theneed for multiple breath holds reduces the risk of changes in breathhold positions or heart rate, results in higher patient comfort andfacilitates inclusion of DENSE in a clinical routine protocol.

  • 239.
    Sigfridsson, Andreas
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Haraldsson, Henrik
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Takase, S.
    Mie University, Tsu, Mie, Japan.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Sakuma, H.
    Mie University, Tsu, Mie, Japan.
    Flip Angle Strategies for Multiphase DENSE2009Conference paper (Refereed)
    Abstract [en]

    In multiphase DENSE MRI, available signal decreases during the cardiac cycle due to excitation and T1-relaxation. Because of this, a widely used method is to vary the flip angle to yield constant SNR during the cardiac cycle. Unfortunately, this may lead to significant sacrifices of SNR in the early cardiac phases.

  • 240.
    Sigfridsson, Andreas
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Haraldsson, Henrik
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Takase, S.
    Mie University, Tsu, Mie, Japan.
    Sakuma, H.
    Mie University, Tsu, Mie, Japan.
    Multi Slice DENSE in a Single Breath Hold2009Conference paper (Refereed)
  • 241.
    Sigfridsson, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Kvitting, John-Peder Escobar
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Wigström, Lars
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Five-dimensional MRI Incorporating Simultaneous Resolution of Cardiac and Respiratory Phases for Volumetric Imaging2006In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 25, no 1, p. 113-121Article in journal (Refereed)
    Abstract [en]

    Purpose

    To develop a new volumetric imaging method resolved over both the cardiac and respiratory cycles, to enable future physiological and pathophysiological studies of respiratory-related cardiac motion.

    Materials and Methods

    An acquisition scheme is proposed whereby the k-space acquisition order is controlled in real-time by the current cardiac and respiratory phases. To reduce eddy-current effects induced by sudden jumps in k-space, the acquisition order is further optimized by the use of a Hilbert curve trajectory in the ky-kz plane. A complete three-dimensional (3D) k-space is acquired for all combinations of cardiac and respiratory phases, yielding a five-dimensional (5D) data set after retrospective reconstruction.

    Results

    Left (LV) and right ventricular (RV) wall excursion was measured in a healthy volunteer. Diastolic LV diameter was shown to increase during expiration and decrease during inspiration, as expected from previous echocardiography studies. The LV volume was estimated for all cardiac and respiratory phases with the use of a fully 3D segmentation tool. The results confirmed that the diastolic LV volume increased during expiration and decreased during inspiration.

    Conclusion

    With its ability to measure motion anywhere in the heart, the described technique provides a promising approach for in-depth description of interventricular coupling, including 3D ventricular volumes, during both the cardiac and respiratory cycles.

  • 242.
    Sigfridsson, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Wigström, Lars
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Kvitting, John-Peder Escobar
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    k-t2 BLAST: Exploiting spatiotemporal structure in simultaneously cardiac and respiratory time-resolved volumetric imaging2007In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 58, no 5, p. 922-930Article in journal (Refereed)
    Abstract [en]

    Multidimensional imaging resolving both the cardiac and respiratory cycles simultaneously has the potential to describe important physiological interdependences between the heart and pulmonary processes. A fully five-dimensional acquisition with three spatial and two temporal dimensions is hampered, however, by the long acquisition time and low spatial resolution. A technique is proposed to reduce the scan time substantially by extending the k-t BLAST framework to two temporal dimensions. By sampling the k-t space sparsely in a lattice grid, the signal in the transform domain, x-f space, can be densely packed, exploiting the fact that large regions in the field of view have low temporal bandwidth. A volumetric online prospective triggering approach with full cardiac and respiratory cycle coverage was implemented. Retrospective temporal interpolation was used to refine the timing estimates for the center of k-space, which is sampled for all cardiac and respiratory time frames. This resulted in reduced reconstruction error compared with conventional k-t BLAST reconstruction. The k-t2 BLAST technique was evaluated by decimating a fully sampled five-dimensional data set, and feasibility was further demonstrated by performing sparsely sampled acquisitions. Compared to the fully sampled data, a fourfold improvement in spatial resolution was accomplished in approximately half the scan time.

  • 243.
    Sjöblom, Peter
    et al.
    Linköping University, Department of Medicine and Health Sciences. Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Länne, Toste
    Linköping University, Department of Medicine and Health Sciences, Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Nyström, Fredrik
    Linköping University, Department of Medicine and Health Sciences, Internal Medicine . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medicine, Department of Endocrinology and Gastroenterology UHL.
    Östgren, Carl Johan
    Linköping University, Department of Medicine and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Finspång, Primary Health Care Centre.
    Microalbuminuria but not reduced GFR is a marker of subclinical atherosclerosis and arterial stiffness in type 2 diabetes in DIABETOLOGIA, vol 53, issue , pp2010In: DIABETOLOGIA, Springer Science Business Media , 2010, Vol. 53Conference paper (Refereed)
    Abstract [en]

    n/a

  • 244.
    Smedby, Örjan
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Wirell, Staffan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology.
    Kvist, Joanna
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, Division of Physiotherapy.
    Silén, Charlotte
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Göran, Pettersson
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, CSELAB - Cognitive Systems Engineering Laboratory.
    Fyrenius, Anna
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Interactive volume rendering 3D images for anatomy learning on low-end computers2007In: ECR - European Congress of Radiology,2007, 2007Conference paper (Other academic)
    Abstract [en]

      

  • 245. Sparring Björkstén, Karin
    et al.
    Ekberg, Stefan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiation Physics. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Säfström, Pia
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL.
    Dige, N
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    A computerized human reference brain for rCBF/SPET technetium-99m exametazime (HMPAO) investigation of elderly2004In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 24, no 4, p. 196-204Article in journal (Refereed)
    Abstract [en]

    Using the bull's eye approach, a reference brain from the single photon emission tomography (SPET) images of 10 subjects aged 62-81 years with excellent mental and physical health was constructed. SPET images were acquired twice, 1 week apart, using a single detector rotating gamma camera collecting 64 planar images over a 360° orbit. The centre of each transaxial slice was first defined with an automatic edge detecting algorithm applied to an anterior-posterior and a side profile of the brain. Each slice was divided into 40 sectors. Maximum counts/pixel in each sector was picked. The 40 maximum count values from one transaxial slice were allowed to form a horizontal row in a new parametric image on the x-axis and slice number from the vertex to the basal parts of the brain on the y-axis. This new image was scaled to a 64 × 16 pixel matrix by interpolation, which meant a normalization of all studies to the same size. The parametric image in each subject was scaled with regard to intensity by a factor calculated by a normalization procedure using the least squares analysis. Mean and SD for each pixel were calculated, thereby constructing a 'mean parametric image', and a 'SD parametric image'. These two images are meant to be used as the reference brain for evaluation of patient studies. This method can be used for objective measurements of diffuse brain changes and for pattern recognition in larger groups of patients. Statistical multifactorial analysis of parameters used for acquisition and data processing is possible. © 2004 Blackwell Publishing Ltd.

  • 246.
    Stratelis, Georgios
    et al.
    Linköping University, Department of Medical and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in West Östergötland, Primary Health Care in Motala.
    Fransson, Sven Göran
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Schmekel, Birgitta
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Jakobsson, Per
    Linköping University, Department of Medical and Health Sciences, Pulmonary Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Respiratory Medicine UHL.
    Mölstad, Sigvard
    Linköping University, Department of Medical and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences.
    High prevalence of emphysema and its association with BMI: A study of smokers with normal spirometry2008In: Scandinavian Journal of Primary Health Care, ISSN 0281-3432, E-ISSN 1502-7724, Vol. 26, no 4, p. 241-247Article in journal (Refereed)
    Abstract [en]

    Objectives: To evaluate to what extent emphysema was evident, as identified by High Resolution Computed Tomography (HRCT), in smokers with normal lung function and to relate age, gender, smoking history, and body mass index (BMI) to the HRCT results. A secondary aim was to study to what extent emphysema was present in smokers with lower normal values of lung function defined as FEV1/FVC ratio percentage of predicted value (89-93% of predicted value for males and 90-93% for females) or FEF50 60% of predicted compared with smokers without this definition.

    Methods: Fifty-nine smokers, with a mean age of 53 years and with normal lung function, were examined with HRCT.

    Results: Emphysema evidenced visually by HRCT was present in 43% of the subjects. Using a 0-5 grade scale (0=normal finding; 5=emphysema in most slices), the degree of emphysema was almost exclusively 3-4. The type of emphysema was distributed as centrilobular emphysema predominant in 43.5%, paraseptal emphysema predominant in 43.5%, and as an equal mixture of these types in 13%. The presence of emphysema did not differ between the group of smokers with lower normal values of lung function and the rest of the smokers. Smokers with emphysema had significantly lower BMI than those devoid of emphysema, 24 and 27 respectively (p0.0011).

    Conclusion: There was a high occurrence of visual emphysema in middle-aged smokers with normal lung function. The densitometric quantitative analysis method is inadequate for detecting mild emphysema. High prevalence of emphysema was associated with low BMI.

  • 247.
    Strotman, JM
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Richter, Arina
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Kukuluski, T
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Voigt, J-U
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Fransson, Sven Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hatle, L
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Sutherland, GR
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Doppler Myocardial Imagning in the Assessment of Regional Myocardial Function in Longitudinal Direction Pre- and Post-PTCA.2001In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 2, p. 178-186Article in journal (Refereed)
  • 248. Strotmann, J.M.
    et al.
    Richter, Arina
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Cardiology . Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Kukulski, T.
    Voigt, J.-U.
    Fransson, Sven Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hatle, L.
    Sutherland, G.R.
    Doppler myocardial imaging in the assessment of regional myocardial function in longitudinal direction pre- and post-PTCA2001In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 2, no 3, p. 178-186Article in journal (Refereed)
    Abstract [en]

    Aims: Doppler myocardial imaging is potentially a sensitive tool to assess regional myocardial velocities pre- and post-percutaneous transluminal coronary angioplasty (PTCA) as a marker of contractility to evaluate short- to medium-term information on functional myocardial recovery following the release of ischaemia. Methods: Thirty patients with single vessel disease were studied to assess regional myocardial peak systolic velocity, systolic velocity time integral and mitral valve plane excursion in longitudinal direction one day pre-, one day post- and 3 months post-PTCA. The patients were assigned to group A with coronary stenoses >70% and group B with stenoses <70%. Results: In group A pre-PTCA the ischaemic segments showed a significantly lower peak systolic velocity and velocity time integral compared with the values one day after PTCA (5.8 ± 1.4 vs 7.7 ± 1.4 cm.s-1, 1.06 ± 0.22 vs 1.23 ± 0.28 cm, P< 0.03). In contrast, mitral valve plane excursion in this group remained unchanged after PTCA for both the ischaemic and non-ischaemic left ventricular wall. In group B no changes of these parameters and no differences in mitral valve plane excursion of the ischaemic and the non-ischaemic left ventricular wall could be seen. Conclusion: With Doppler myocardial imaging it was possible to quantify a number of indices which changed due to the successful release of ischaemia.© 2001 The European Society of Cardiology.

  • 249. Sun, Y
    et al.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Eidenvall, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Loyd, Dan
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Applied Thermodynamics and Fluid Mechanics.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Estimation of pulsatile flow by surface integration of velocity vectors in Doppler ultrasound images from two arthogonal planes1995In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 8, p. 904-914Article in journal (Refereed)
  • 250. Sun, Y
    et al.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Loyd, Dan
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Applied Thermodynamics and Fluid Mechanics.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Mathematical model that characterizes transmitral and pulmonary venous flow velocity patterns1995In: American journal of physiology, ISSN 0002-9513, Vol. 268, p. 476-489Article in journal (Refereed)
23456 201 - 250 of 295
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