Traditional Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the pdf of the poster viewable in the poster hall.
Bowel Motion & Gas

 
Tuesday May 10th
Exhibition Hall  13:30 - 15:30

873.   Assessment of Motion patterns in free breathing MRI of the abdomen using continuously tagged imaging 
Andre M. J. Sprengers1, Matthan W.A. Caan1, Aart J. Nederveen1, Jaap Stoker1, and Rolf M. Lamerichs2
1Radiology, Academic Medical Centre, Amsterdam, Netherlands, 2Research, Philips, Eindhoven, Netherlands

 
This study presents the use of continuously tagged imaging for detailed motion assessment in the entire abdomen during free breathing. MRI in the abdominal area is hampered by low tissue contrast and abundant presence of motion artifacts. Motion suppression is never 100% effective and increases the burden of the protocol. The continuously tagged method provides high spatiotemporal resolution information of the unconstrained motion in the abdomen suitable for both motion correction and diagnostic purposes i.e. motility assessment.

 
874.   Motility assessment using continuously tagged imaging 
Andre M. J. Sprengers1, Marije P. van der Paardt1, Frank Zijta1, Matthan W.A. Caan1, Rolf M. Lamerichs1,2, Aart J. Nederveen1, and Jaap Stoker1
1Radiology, Academic Medical Centre, Amsterdam, Netherlands, 2Research, Philips, Eindhoven, Netherlands

 
Synopsis: This study presents the use of continuously tagged imaging for assessment of bowel motility. The tagging prepulse induces stripe patterns in MR images from which motion information can be extracted if the pattern is deformed by tissue motion. However, tagging was developed for cardiac (periodic motion) and the required determination of the patterns can easily lead to high workloads, a common problem in motility assessment methods. This study presents continuously tagged MR acquisition as a fast, non-invasive method for motility assessment over the entire abdominal area including automated post processing.

 
875.   Non-Invasive MRI-based 3D Volumetric Serial Assessments of Physiologic Large Intestine Gas - Proof of Principle 
John Butler1, Jodi Miller1,2, Harry Marshall1,2, Ally Silavi1, John Patrick1,2, William Pavlosky3, Gregor Reid1,4, Don Taves3, Jamie Gregor5, Khaleel Sultan5, Deanna Carlsen6, Artem Khlebnikov6, Denis Guyonnet7, Sophie Legrain-Raspaud7, Frank S Prato1,2, R Terry Thompson1,2, and Robert Z Stodilka1,2
1Lawson Health Research Institute, London, Ontario, Canada, 2Medical Biophysics, University of Western Ontario, London, Ontario, Canada, 3Nuclear Medicine, St. Joseph's Hospital, London, Ontario, Canada, 4Microbiology, University of Western Ontario, London, Ontario, Canada, 5Gastroenterology, London Health Sciences Center, London, Ontario, Canada, 6The Dannon Company, White Plains, New York, United States, 7Danone Research, Palaiseau, Cedex, France

 
This study uses a single-shot MRI technique to provide a 3D dataset for semi-automatic image segmentation to determine large bowel gas volume. An axial interleaved single shot HASTE breath-hold sequence, acquired in isocenter mode at three table positions was used. Three sets of images were acquired in five subjects on a restricted diet, over a day for two consecutive days. Prior to the last two scans on the 2nd day the subjects were given a lactulose challenge. The total gas volume in the large bowel was calculated using an operator interactive segmentation routine to extract the voxels containing gas. The measured gas volumes were consisted in the same subject in Day 1 and 2, but there was larger inter subject variability in the gas volumes. The lactulose did not have a significant effect on gas volumes.

 
876.   Feasibility of 3.0T MR Angiography For Pre-Operative Vascular Evaluation of Pediatric Patients Undergoing Liver/Small Bowel Transplantations. 
Conor Meehan1, Saeed Mirsadraee1,2, and Paul Finn1
1Department of Radiological Sciences, University of California Los Angeles, Los Angeles, California, United States, 2Clinical Research Imaging Centre, University of Edinburgh, Edinburgh, United Kingdom

 
This study evaluates the feasibility of 3.0T MR angiography in evaluation of pre-transplant perdiatric patients. Accuracy of the technique in the evaluation of vascular structures is discussed.

 
877.   Akt1 deficient mice show resistance to DSS-colitis induced leak of albumin-based contrast media from the colon vasculature 
Katrien Vandoorne1, Tegest Aychek2, Hagit Dafni1, Brian A. Hemmings3, Steffen Jung2, and Michal Neeman1
1Biological Regulation, Weizmann Institute, Rehovot, Israel, 2Immunology, Weizmann Institute, Rehovot, Israel, 3Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland

 
The etiology of inflammatory bowel disease (IBD), a group of inflammatory conditions of the intestinal tract, remains largely unknown. Akt1, a protein kinase, is a major mediator of angiogenic signaling, acting downstream of vascular endothelial growth factor (VEGF). In this study, we reported significantly decreased permeability (PS) in Akt1 deficient mice using macromolecular DCE-MRI, validated by histology. This decreased permeability of albumine-based contrast agent implies less leakage of plasma proteins and thus, limited disease progression. These results provide direct evidence that Akt1 enhances DSS-induced colitis. MRI proved to provide high sensitivity for in vivo detection of reduced permeability in colitis.

Traditional Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the pdf of the poster viewable in the poster hall.
Hyperpolarized Gas: Techniques & Applications

 
Wednesday May 11th
Exhibition Hall  13:30 - 15:30

878.   Single-Acquisition Imaging of Hyperpolarized 129Xe in the Gas and Dissolved Phases using an Interleaved 3D-Radial Sequence 
Suryanarayanan Sivaram Kaushik1,2, Gary P Cofer2, Matthew S Freeman2,3, Zackary I Cleveland2, and Bastiaan Driehuys2
1Biomedical Engineering, Duke University, Durham, NC, United States, 2Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 3Medical Physics, Duke University Medical Center, Durham, NC, United States

 
The ~200 ppm chemical shift difference between gaseous hyperpolarized (HP) 129Xe and HP 129Xe dissolved in the lung tissues (dissolved phase) makes this agent an excellent probe of pulmonary gas exchange processes. Dissolved phase HP 129Xe images have displayed profound evidence of gravity-dependent gas exchange heterogeneity. However, a deeper understanding of lung function, and quantitative analysis of ventilation and gas exchange would benefit from simultaneous imaging of 129Xe in the dissolved and gas-phases. In this work, we demonstrate a method to acquire both the gas and dissolved phase images of 129Xe in a single acquisition, using an interleaved 3D-radial sequence.

 
879.   3D MRI of the Hyperpolarized 129Xe Distribution in the Rat Brain 
John Nouls1,2, Zackary i Cleveland1,2, Matthew S Freeman3, Harald E. Moeller4, Laurence W Hedlund1,2, and Bastiaan Driehuys1,2
1Department of Radiology, Duke University, Durham, NC, United States, 2Center for in vivo Microscopy, Duke University, Durham, NC, United States, 3Medical Physics, Duke University, 4Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany

 
We demonstrate that acquiring isotropic, 3D images of the 129<\sup>Xe distribution in the rat brain is feasible. The images are obtained by simple inhalation delivery within 5 min. However, the intensity in these images display significant heterogeneity. The presence of this heterogeneity, which was not reported in earlier 2D imaging studies, suggests that the distribution of 129<\sup>Xe in the brain is sensitive to a variety of physiologically and anatomically important factors including perfusion, tissue type, and tissue chemistry.

 
880.   Quantitative Assessment of Emphysema with Dissolved-Phase and Gas-phase Hyperpolarized 129Xe MRI in Mice 
Hirohiko Imai1, Atsuomi Kimura1, Satoshi Iguchi1, and Hideaki Fujiwara1
1Department of Medical Physics and Engineering, Division of Health Sciences, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan

 
We investigated the feasibility of quantitative assessment of emphysema with a combination of gas-phase (GP) and dissolved-phase (DP) hyperpolarized (HP) 129Xe lung MRI in spontaneously breathing mice. GP and DP 129Xe were imaged by using ultrashort TE (UTE) sequence. By using these images, the fraction F, which is the ratio of the magnetization of 129Xe diffused into septa within 50 ms relative to that of the gas space, was regionally evaluated. The F value was significantly reduced in elastase-induced emphysema model, reflecting the alveolar tissue destruction and the value showed significant correlation with histologically derived surface-to-volume ratio (S/V).

 
881.   Regional Ventilation Mapping of the Rat Lung Using Hyperpolarized 3He and 129Xe Magnetic Resonance Imaging 
Marcus John Couch1,2, Alexei V Ouriadov1, and Giles E Santyr1,3
1Imaging Research Laboratories, Robarts Research Institute, The University of Western Ontario, London, ON, Canada, 2Department of Physics and Astronomy, The University of Western Ontario, London, ON, Canada, 3Department of Medical Biophysics, The University of Western Ontario, London, ON, Canada

 
In this work, hyperpolarized 3He and 129Xe MRI was used to measure regional ventilation in the normal rat lung using the dynamic gas signal from inside the lungs. This method used a variable flip angle approach (FAVOR) to mitigate the effects of RF pulses and relaxation both in the ventilator system and in the rat lung. A theoretical model was used to fit signal enhancement curves on a pixel-by-pixel basis to generate two-dimensional maps of the ventilation parameter, r, which was defined as the fractional refreshment of gas per breath. Ventilation gradients were calculated in the superior/inferior and anterior/posterior directions.

 
882.   Quantifying Pulmonary Gas Transport Efficiency Using Hyperpolarized Xenon-129 
Kai Ruppert1, Jaime F. Mata1, Isabel M Dregely2, Talissa A Altes1, G Wilson Miller1, Stephen Ketel3, Jeff Ketel3, Iulian C Ruset2,3, F William Hersman2,3, and John P Mugler III1
1University of Virginia, Charlottesville, VA, United States, 2University of New Hampshire, Durham, NH, United States, 3Xemed LLC, Durham, NH, United States

 
Due to the large chemical shift difference between hyperpolarized Xe129 (HXe129) dissolved in lung tissue and in the alveolar air spaces it is feasible to image both compartments simultaneously, appearing side-by-side in the image, by using a suitable imaging bandwidth. The weighting of the dissolved-phase contrast can be shifted from exchange-site dominant to blood-pool dominant through an adjustment of the TR/FA combination of the acquisition. Thereby it is feasible to monitor and quantify the HXe129 gas transport processes throughout the pulmonary and cardiovascular system up to the aortic arch.

 
883.   3D Imaging of Pulmonary Ventilation and Perfusion in Rats using Hyperpolarized 129Xe 
Zackary I Cleveland1, Harald E Moller1,2, Laurence W Hedlund1, John Nouls1, Matthew Freeman1,3, Yi Qi1, and Bastiaan Driehuys1
1Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 2Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 3Graduate Program in Medical Physics, Duke University, Durham, United States

 
We demonstrate that 3D images of both ventilation and pulmonary perfusion can be acquired in rats using hyperpolarized 129Xe. To generate the perfusion images, 129Xe was infused into the blood using an extracorporeal circuit containing a hydrophobic membrane based, gas exchange module. The spatial resolution of these perfusion images (2󫎾 mm3) is similar to that obtained from conventional nuclear imaging modalities, but can be acquired with a five-fold advantage in temporal resolution. Thus, 129Xe MRI can be used to rapidly assess the distribution of ventilation and perfusion and will be useful in investigating animal models of acute lung disease.

 
884.   Improved Separation and Quantification of Xe-129 Dissolved-Phase Resonances in the Lung 
Jaime Mata1, Kai Ruppert1, Peter Sylvester1, Isabel Dregely2, Talissa Altes1, Iulian Ruset2, William Hersman2, Grady Miller1, steve Ketel2, Jeff Ketel2, and John Mugler III1
1Radiology, University of Virginia, Charlottesville, Virginia, United States, 2Xemed, LLC, Durham, NH, United States

 
Using hyperpolarized Xe-129 gas and Chemical Shift Imaging, we directly calculate images reflecting the amount of Xe-129 in the airspaces, and dissolved in the lung tissue, Red Blood Cells (RBC), and other compartments, thus obtaining detailed spatial information regarding how Xe-129 is distributed in those different compartments and providing regional information about lung physiology.

 
885.   Measurement of 129Xe Gas Apparent Diffusion Coefficient Anisotropy in an Elastase-Instilled Rat Model of Emphysema 
Mathieu Boudreau1,2, Xiaojun Xu3, William Dominguez-Viqueira4, and Giles Santyr1,5
1Imaging Research Laboratories, John. P. Robarts Research Institute, London, Ontario, Canada, 2Dept. of Physics and Astronomy, University of Western Ontario, London, Ontario, Canada,3University of Sheffield, Sheffield, United Kingdom, 4Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada, 5Dept. of Medical Biophysics, University of Western Ontario, London, Ontario, Canada

 
The apparent diffusion coefficient (ADC) of hyperpolarized noble gases has been demonstrated to behave anisotropically in the lung. In this work, we investigate hyperpolarized 129Xe gas ADC anisotropy in vivo at 74 mT in an elastase-instilled rat model of emphysema. The effect of diffusion time (6 and 100 ms) on 129Xe anisotropic ADC was quantified using the Yablonskiy model in sham instilled and elastase-instilled rats. The largest change in DL was observed at 100 ms (13% increase for the elastase compared to the sham rats), and for DT at 6 ms a 25% increase was observed.

 
886.   Hyperpolarized 129Xe Gas and Dissolved Phase Lung Imaging using IDEAL 
Alexei V Ouriadov1, Matthew Fox1,2, Lanette Friesen-Waldner3, Charles McKenzie3,4, and Giles Santyr3,5
1Robarts Research Institute, The University of Western Ontario, London, Ontario, Canada, 2The Department of Physics, The University of Western Ontario, 3The Department of Medical Biophysics, The University of Western Ontario, 4Biomedical Engineering Program, The University of Western Ontario, 5Robarts Research Institute, The University of Western Ontario

 
MR imaging using hyperpolarized 129Xe provides non-invasive approach for probing lung structure and function. In addition to this 129Xe is able to diffuse across the blood-gas barrier giving rise to CS in compartments such as tissue/RBC. So measurements of ventilation(V), perfusion(Q) and diffusing capacity of xenon(DXe) are possible. In order to obtain simultaneous V, Q and DXe maps we propose to use modified Dixon method called IDEAL. The preliminary results obtained from the rat lung demonstrate the feasibility of using IDEAL for simultaneous hyperpolarized 129Xe imaging of the gas signal and the signal from the tissue/RBC compartments in the lung.

 
887.   Recovery and Purification of 3He Gas from Pulmonary MRI 
Sean Alexander Lourette1, Allen W Che2, Jason C Woods1,2, and Mark S Conradi1,2
1Physics, Washington University, St. Louis, Missouri, United States, 2Radiology, Washington University, St. Louis, Missouri, United States

 
To reduce the cost of hyperpolarized 3He MR experiments, used for measuring restricted diffusion, ventilation uniformity, and oxygen distribution in lungs, 3He should be recaptured and purified for reuse in future experiments. A device has been constructed that collects exhaled gas into flexible bags, using activated carbon to remove N2, O2, and other exhaled contaminants from the3He by means of physical adsorption at 77 K. The purified 3He is cryogenically recompressed, mixed with nitrogen buffer gas, and used to refill Rb-glass cells for hyperpolarization.

 
888.   Xenon Hyperpolarized by the Dissolution-DNP Method 
Jan Henrik Ardenkjaer-Larsen1, Haukur Johannesson1, Jan Wolber2, Nick Kuzma3, and Rahim Rizi3
1GE Healthcare, Broendby, Denmark, 2GE Healthcare, United Kingdom, 3University of Pennsylvania, United States

 
It is demonstrated that the dissolution-DNP method is capeable of producing Xenon gas with high polarization in the gas phase. The maximum obtained solid state 129Xe polarization was 23%. The method would allow for high production rates of Xenon gas with high polarization.

 
889.   Enhancement of 129Xe polarisation by off-resonant optical pumping 
Steven Richard Parnell1, Martin H Deppe1, Juan Parra-Robles1, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
A high power narrow line width external cavity diode laser is investigated for rubidium spin exchange optical pumping of 129Xe. This tunable photon source has a constant line width, independent of operating power or wavelength within a 1 nm tuning range. When using this laser, an increase in the 129Xe nuclear polarisation is observed when optically pumping at a lower wavelength than the measured Rb absorption. The exact detuning from the absorption for the highest polarisation is dependent upon the gas density. Furthermore, at high power and/or high Rb density, a reduction of the polarisation occurs at the optimum wavelength as previously reported in SEOP studies of 3He which is consistent with high absorption close to the cell front face. These results are encouraging for moderate high throughput polarisation of 129Xe in the mid pressure range.

 
890.   Spectrally narrowed 1.5 kW optical pumping laser for large-scale SEOP production of hyperpolarized gases 
F. W. Hersman1,2, Jan H Distelbrink2, Jeff Ketel2, David Watt2, Stephen Ketel2, Walter Porter2, Steve Bryn2, Aaron Hope2, and Iulian Constantin Ruset2
1Department of Physics, University of New Hampshire, Durham, NH, United States, 2Xemed LLC, Durham, NH, United States

 
Hyperpolarized gases xenon-129 and helium-3 are novel imaging agents for pulmonary functional MRI that are in investigational use in clinical research. Producing these gases with spin-exchange optical pumping (SEOP) requires high power laser sources spectrally narrowed at 795nm. We present a new implementation of optical elements incorporated in an external cavity spectrally-locked diode laser system and report measurements confirming production of 1.5 kilowatt laser power with spectral width of less than 0.2nm at 795nm central wavelength and angular divergence less than 0.1mr (fast axis) X 5mr (slow axis).

 
891.   Hyperpolarized Helium Measurements of PAO2 Correlate with Neutrophil Inflammation in the Rat Bleomycin Model 
Puttisarn Mongkolwisetwara1, Evguenia Borissova Arguiri2, Kiarash Emami1, Yi Xin1, Nicholas N. Kuzma1, Stephen J. Kadlecek1, Yinan Xu1, Harilla Profka1, Melpo Christofidou-Solomidou2, Milton D Rossman2, Masaru Ishii3, and Rahim R. Rizi4
1Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Pulmonary Division, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 3Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, Maryland, United States, 4Radiology, University of Pennsylvania, Philadelphia, Pennsylvania

 
Idiopathic Pulmonary Fibrosis (IPF) is a relatively rare and most debilitating disease due to the fact that it is a progressive disorder whose pathogenesis is still unknown. Therefore, determining the causes of IPF and finding a probe to monitor potential treatments are essential goals of this study. The pulmonary function measurement by 3He MRI is a sensitive tool in assessing lung microstructure and function. Significant changes in all parameters of alveolar partial pressure, ADC, and fractional ventilation confirm that we can employ 3He MRI to gauge microstructure (ADC changes), lung function (Fractional Ventilation) and deficient in O2 uptake in alveolar walls (PaO2).

 
892.   Quantitative Assessment of Chronic Exposure to Cigarette Smoke in Mouse Lungs by Hyperpolarized Gas MRI 
Yi Xin1, Kiarash Emami1, Stephen J. Kadlecek1, Puttisarn Mongkolwisetwara1, Nicholas N. Kuzma1, Harilla Profka1, Yinan Xu1, Hooman Hamedani1, Benjamin M. Pullinger1, Rajat K. Ghosh1, Jennia N. Rajaei1, Stephen Pickup1, Masaru Ishii2, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, Maryland, United States

 
We present measurements of lung microstructure using 3He Apparent Diffusion Coefficient (ADC) and Ventilation in smoked mice. After six months of smoke exposure, the smoke-exposed group has significantly larger ADC values, while the ventilation maps are visually and quantitatively unchanged. We conclude that this smoked mice model more closely resembles the disease model in human emphysematous rather than human chronic bronchitic disease.

 
893.   Non-invasive Assessment of Pulmonary Developmental Deficiency in a Model of Transgenic Mice using Hyperpolarized Gas Diffusion MRI 
Amy Barulic1, Kiarash Emami2, Yi Xin1, Puttisarn Mongkolwisetwara1, Harilla Profka1, Nicholas N. Kuzma1, Jeanine M. D'Armiento3, Takayuki Shiomi4, Stephen J. Kadlecek1, Yinan Xu1, Hooman Hamedani1, Benjamin Michael Pullinger1, Rajat Ghosh1, Jennia Rajaei1, Stephen Pickup1, Masaru Ishii5, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Radiology, University of Pennsylvania, PA, Pennsylvania, United States, 3Departments of Medicine and Surgery, Columbia University, New York, NY, United States, 4Department of Molecular Medicine, Columbia University, New York, NY, United States, 5Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
Hyperpolarized 3He gas MRI was used to assess the SFRP1 knockout mice lung microstructure. SFRP1 knockout mice demonstrated a significant increase in the overall 3He apparent diffusion coefficient value compared to their na飗e counterparts. Results suggest that this technique can serve as a sensitive and non-invasive in vivo imaging tool for longitudinal studies of development and repair response in pulmonary cells, as well as for the study of lung embryogenesis and monitoring the progression of therapeutic interventions for various lung pathologies.

 
894.   Imaging of Airway Remodeling in a Murine Model of Bronchial Hyper-responsiveness Using Hyperpolarized Gas MRI 
Kiarash Emami1, Jennia N. Rajaei1, Yi Xin1, Puttisarn Mongkolwisetwara1, Harilla Profka1, Stephen J. Kadlecek1, Hooman Hamedani1, Yinan Xu1, Amy Barulic1, Stephen Pickup1, Nicholas N. Kuzma1, Blerina Ducka2, Angela Haczku2, Masaru Ishii3, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Pulmonary & Critical Care Division, University of Pennsylvania Medical Center, Philadelphia, PA, United States,3Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, Maryland, United States

 
Regional measurements of fractional ventilation provide a sensitive and noninvasive tool for studying physiological changes which occur within the asthmatic lung. Evidence shows a statistically significant decline in regional ventilation for the asthmatic cohort compared to that of the na飗e and control cohorts, while ADC values did not exhibit a similar decline, indicating that airway remodeling which contributes to lower ventilation is a result of asthmatic responses. Results indicate that hyperpolarized gas MRI and the quantitative measurements obtained from it may yield promising advances in early detection and diagnosis of asthma.

 
895.   Imaging lung microstructure in mice with hyperpolarized 3He diffusion MRI 
Wei Wang1,2, Nguyet M. Nguyen3, Dmitriy A. Yablonskiy1,2, Alexander L. Sukstanskii2, Emir Osmanagic2, Richard A. Pierce3, Mark S. Conradi1,2, and Jason C. Woods1,2
1Physics, Washington University in St. Louis, St. Louis, MO, United States, 2Radiology, Washington University in St. Louis, St. Louis, MO, United States, 3Internal Medicine, Washington University in St. Louis, St. Louis, MO, United States

 
Quantitative measurement of lung microstructure is of great significance in assessment of pulmonary disease, particularly in the earliest stages. Our MRI-based 3He lung morphometry technique was previously developed and validated for human lungs, and was recently extended to ex-vivo mouse lungs. The technique yields accurate, quantitative information about the microstructure and geometry of acinar airways. In this study the 3He lung morphometry technique is successfully implemented for in-vivo studies of mice. Results indicate excellent agreement between in-vivo morphometry via 3He MRI and microscopic morphometry after sacrifice. This opens up new avenues for application of the technique as a precise, noninvasive, in-vivo biomarker of changes in lung microstructure, within various mouse models of lung disease.

 
896.   Ventilation strategy to minimize the effect of residual gas volume on ADC in rat lungs 
Laura Carrero-Gonzalez1,2, Thomas Kaulisch1, Jesus Ruiz-Cabello2,3, Jose Manuel Perez-Sanchez4, German Peces-Barba5, Detlef Stiller1, and Ignacio Rodriguez2,3
1Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Baden-W黵ttemberg, Germany, 2Universidad Complutense de Madrid, Madrid, Spain, 3CIBER de Enfermedades Respiratorias, Madrid, Spain, 4Unit de Recherche en R閟onance Magn閠ique M閐icale (UMR 8081), Univ.Paris-Sud, CNRS, Orsay, France, 5Fundaci髇 Jim閚ez-D韆z, Madrid, Spain

 
Apparent diffusion coefficient (ADC) of HP-gases is a parameter that reflects changes in lung microstructure but it depends on many physiological and experimental variables. The application of a positive end expiratory pressure (PEEP) causes an increase of the residual volume. If incoming and residual gases do not have similar diffusion coefficient, the obtained ADC values will be affected. A proposed single breath-hold protocol uses 4He-O2 for ventilation and HP3He-N2 for imaging. Both gas mixtures have a very similar diffusion coefficient. ADCs obtained from the proposed strategy show to be independent of PEEP, thus minimizing the effect of the different residual volumes.

 
897.   Deflation-induced changes in alveolar-duct geometry via 3He lung morphometry, with histological validation 
Adam J Hajari1,2, Alex L Sukstanskii2, Dmitriy A Yablonskiy1,2, Richard A Pierce3, Gaetan Deslee4, and Jason C Woods1,2
1Physics, Washington University, St. Louis, MO, United States, 2Radiology, Washington University, St. Louis, MO, United States, 3Internal Medicine, Washington University, St. Louis, MO, United States, 4Service de Pneumologie, INSERM U903, Reims, France

 
In this study we have measured alveolar and acinar duct sizes at physiologically relevant volumes in six normal excised canine lungs using a 3He lung morphometry technique optimized for measurements of canine sized airways. Our results imply that during a significant decrease in lung volume (from TLC to 63% of TLC), the acinar duct radius decreases by 17% while the alveolar depth increases by 9%. The 3He morphometry results are in good agreement with histology measurements of the same parameters from the same lungs.

 
898.   Single lobe emphysema induction in the rat lung detected with diffusion-weighted 3He-MRI 
Laura Carrero-Gonzalez1,2, Thomas Kaulisch1, Jesus Ruiz-Cabello2,3, Detlef Stiller1, and Ignacio Rodriguez2,3
1Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Baden-W黵ttemberg, Germany, 2Universidad Complutense de Madrid, Madrid, Spain, 3CIBER de Enfermedades Respiratorias, Madrid, Spain

 
Apparent diffusion coefficient (ADC) reflects changes in lung microstructure and it is used as a detector of lung diseases. Instillation of elastase in the lung produces emphysema, which is characterized by higher airspaces, higher compliance and higher residual volume compared to healthy tissue. It has been proved the feasibility of instilling elastase in only one lung using the other lung of the rat as an internal control. ADC values from elastase-treated and healthy lungs showed significant differences at the end of the expiration, but not during a full-inspiration breath-hold (23mbar). A special ventilation protocol reduces the effect on the ADC due to the different diffusivity of mixtures with either different gases composition or different gases concentration.

 
899.   Quantitative Imaging of Alveolar Recruitment with Hyperpolarized Gas MRI 
Maurizio F. Cereda1, Kiarash Emami2, Stephen J. Kadlecek2, Yi Xin2, Puttisarn Mongkolwisetwara2, Harilla Profka2, Amy Barulic2, Stephen Pickup2, Nicholas N. Kuzma2, Masaru Ishii3, Hooman Hamedani2, Benjamin M Pullinger2, Rajat Ghosh2, Jennia Rajaei2, Clifford S. Deutschman1, and Rahim R. Rizi2
1Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States,3Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, Maryland, United States

 
Atelectasis, often caused by a mechanical ventilator, promotes lung injury, whose mechanisms are not fully understood. Understanding these underlying mechanisms requires simultaneous measurements of ventilated air space and alveolar size, which can be achieved through the use of hyperpolarized gas MRI technology. Additionally, this technique can show how alveolar recruitment maneuvers reestablish a normal pattern of airspace inflation.

 
900.   Imaging Regional Alterations of Gas Exchange in a Murine Model of Emphysema 
Puttisarn Mongkolwisetwara1, Kiarash Emami1, Hooman Hamedani1, Harilla Profka1, Yi Xin1, Yinan Xu1, Nicholas N. Kuzma1, Stephen J. Kadlecek1, Masaru Ishii2, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
An observable change in alveolar partial pressure of oxygen between controlled and elastase-induced mice shows that our measurement of alveolar partial pressure of oxygen by 3He MRI is sensitive enough to differentiate between diseased and normal animals. This confirms that we can utilize 3He's ability to interact with excessive oxygen partial pressure due to the damaged alveolar walls of elastate-induced mice. Likewise, the decrease in fractional ventilation and the increase in mean linear intercept in diseased mice by 14.29% and 34.66% verifies the abnormality in the lung function stemming from the disease.

 
901.   3D 3He and 1H MR Imaging of Regional Pulmonary Injury Induced by Ozone 
John Nouls1,2, Erin Potts3, W Michael Foster3, and Bastiaan Driehuys1,2
1Department of Radiology, Duke University, Durham, NC, United States, 2Center for in vivo Microscopy, Duke University, Durham, NC, United States, 3Department of Pulmonary and Critical Care Medicine, Duke University

 
Ambient ozone (O3) is a major environmental air pollutant, which significantly impacts public health and exacerbates disease in subjects with asthma and chronic obstructive pulmonary disease. While much is known about the deleterious effect of O3 on global lung function, much less is understood about its effects regionally. To this end hyperpolarized gas MRI has been proposed as an ideal means to address this gap. Here, we demonstrate high-resolution 3D 3He and 1H MRI in ozone-exposed C57BL/6 mice reveals striking regional ventilation impairment and bronchial narrowing.

 
902.   Signal Distribution in Dissolved 129Xe MR Images of Healthy Subjects and Subjects with Chronic Obstructive Pulmonary Disease 
Zackary I Cleveland1, S Sivaram Kaushik1,2, Gary P Cofer1, John Nouls1, Monica Kraft3, Jan Wolber4, H Page McAdams5, and Bastiaan Driehuys1
1Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States, 2Department of Biomedical Engineering, Duke University, Durham, NC, United States, 3Department of Medicine, Duke University Medical Center, Durham, NC, United States, 4GE Healthcare, Amersham, United Kingdom, 5Department of Radiology, Duke University Medical Center, Durham, NC, United States

 
We investigate the signal intensity distribution in dissolved 129Xe images from healthy subjects and subjects with chronic obstructive pulmonary disease (COPD). In addition to gravity-dependent SNR gradients, images from healthy subjects display significant isogravitational heterogeneity as measured by the coefficient of variation (CV). Differences in SNR and CV are observed between the left and right lungs. Left-right differences are absent in ventilation images, suggesting tissue compression by the heart alters the signal distribution in the left lung. Gravitational and left-right differences are reduced or absent in subjects with COPD, indicating dissolved 129Xe is sensitive to disease-associated changes in lung physiology.

 
903.   Towards very high net acceleration factors in hyperpolarized 3He human lung Parallel Imaging using SPIRiT 
Martin H. Deppe1, Salma Ajraoui1, and Jim M. Wild1
1Academic Unit of Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
Auto-calibration is essential in Parallel Imaging of the human lung using hyperpolarized noble gases due to limitations of breath-hold reproducibility and gas consumption, resulting in a scan time overhead due to the acquisition of auto-calibration lines. This work presents results on Parallel Imaging of hyperpolarized 3He in human lungs using the SPIRiT reconstruction method, showing that this approach maintains image quality better for high net acceleration factors than the commonly used GRAPPA method. As SPIRiT is an iterative optimization method, the inclusion of random sampling and L1-penalization (Compressed Sensing) is straightforward.

 
904.   Helium-3 Magnetic Resonance Imaging of Treatment Response in Exercise Induced Bronchoconstriction 
Stanley John Kruger1, David Niles1, Grace Parraga2, Sean Fain1, Bernard Dardzinski3, Marcella Ruddy3, Amy Harman3, Stephen Choy2, Scott Nagle4, Christopher Francois4, David G McCormack2, and Nizar Jarjour5
1Medical Physics, University of Wisconsin, Madison, WI, United States, 2Robarts Imaging Institution, University of Western Ontario, London, ON, Canada, 3Merck Research Labs, West Point, PA, United States, 4Radiology, University of Wisconsin, Madison, WI, United States, 5Medicine and Public Health, University of Wisconsin, Madison, WI, United States

 
A double blind therapy trial using He-3 MRI was conducted to evaluate efficacy for exercise induced bronchoconstriction (EIB) using images of ventilation. To track regional changes in defect volume as an endpoint for treatment effect, He-3 MRI was performed at three separate visits at baseline, exercise challenge and 45 min. after challenge in 13 subjects with EIB. Drug was given at 1 of the visits, and placebo at the remaining visits. Results show decreases in ventilation volume at exercise challenge compared to baseline, with treatment reducing this effect. Both decrease in ventilation volume and treatment effect showed preferential regional behavior.

 
905.   Test-Retest and Inter-Reader Reliability of Hyperpolarized Helium-3 MRI in Patients with Exercise-Induced Bronchoconstriction 
David Joseph Niles1, Stanley J Kruger1, Grace Parraga2,3, Bernard Dardzinski4, Marcella Ruddy4, Nizar N Jarjour5, David G McCormack6, Amy Harman4, and Sean B Fain1,7
1Medical Physics, University of Wisconsin, Madison, WI, United States, 2Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, ON, Canada,3Medical Biophysics, University of Western Ontario, London, ON, Canada, 4Merck Research Laboratories, West Point, PA, United States, 5Pediatrics, University of Wisconsin, Madison, WI, United States, 6Division of Respirology, Department of Medicine, University of Western Ontario, London, ON, Canada, 7Radiology, University of Wisconsin, Madison, WI, United States

 
Hyperpolarized helium-3 magnetic resonance imaging (HPHe MRI) is a promising tool for evaluating regional ventilation in obstructive lung disorders; however, its reliability has not been thoroughly established. This study evaluates the reliability of HPHe MRI between exams on separate days and the inter-reader reliability of exams analyzed independently by two blinded readers. Reliability was quantified using the intraclass correlation coefficient (ICC) and a Bland-Altman analysis. Between-day ICC values for four image-based measurements were at least 0.61 and inter-reader ICC values were at least 0.91. These results indicate that HPHe MRI is robust between separate exams and independent evaluators.

 
906.   Evaluating Bronchodilator Effects in Chronic Obstructive Pulmonary Disease using Hyperpolarized Helium-3 Magnetic Resonance Imaging 
Miranda Kirby1,2, Roya Etemad-Rezai3, David G McCormack4, and Grace Parraga1,5
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, 2Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, 3Department of Medical Imaging, The University of Western Ontario, London, Ontario, Canada, 4Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada,5Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada

 
The objective of this study was to evaluate short-acting bronchodilator effects in fourteen subjects with chronic obstructive pulmonary disease (COPD) using hyperpolarized helium-3 (3He) magnetic resonance imaging (MRI), spirometry, and plethysmography before and after administration of salbutamol. 3He MRI ventilation segmentation was performed using a semi-automated k-means clustering algorithm and 3He ADC was calculated using diffusion-weighted imaging. 3He MRI detected significant reductions in 3He clusters that contained no or diminished MR signal (p<.0001) and significant improvements in 3He ventilation clusters (p<.05), but no changes in 3He ADC post-salbutamol (p=.56), indicating that regional distribution of ventilation improves in COPD patients post-bronchodilator.

 
907.   Evaluation of Short Term Reproducibility of Hyperpolarized Helium-3 Magnetic Resonance Imaging of Adult Cystic Fibrosis using a Semi-Automated Segmentation Tool 
Sarah Svenningsen1,2, Miranda Kirby1,2, Hassaan Ahmed1,2, Nigel Paterson3, and Grace Parraga1,4
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, 2Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada,3Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada, 4Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada

 
With the recent rapid development of a wider array of cystic fibrosis (CF) treatment options there is an urgent requirement for precise, practical and sensitive clinical endpoint measures that can be used to determine treatment response and CF disease progression over time. With the generation of a semi-automated method for the determination of pulmonary ventilation in CF, the short-term (7+/- 2 days) precision and specificity of hyperpolarized 3He MRI measurements was evaluated. We were able to conclude that the semi-automated method provides superior precision for the detection of significant changes in pulmonary function over short periods of time.

 
908.   Quantitative evaluation of Ventilation Dynamics in Asthma during methacholine challenge using Hyperpolarized 3He Magnetic Resonance Imaging 
Stephen Costella1,2, Andrew Wheatley1, David McCormack3, and Grace Parraga1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, 2Graduate Program in Biomedical Engineering, University of Western Ontario, London, Ontario, Canada,3Medicine, Division of Respirology, University of Western Ontario, London, Ontario, Canada

 
Pulmonary functional imaging using helium-3 (3He) magnetic resonance imaging (MRI) has provided us with a way to quantitatively evaluate the spatial and temporal functional changes in a variety of respiratory conditions, including asthma. We quantitatively evaluated ventilation defect size and number at baseline, PC20 and after recovery and compared these values with spirometry. Our results suggest that mean defect size is the dominant mechanism for the changes in FEV1 that occur at PC20 as compared to defect count. This provides important new information on the mechanisms involved in asthma exacerbations and insights on prophylaxis to avoid exacerbations.

 
909.   Gas Diffusion Image Reduction Metric with Improved Sensitivity to Heterogeneous Lung Disease 
Ahsan Samiee1, Stephen J. Kadlecek2, Kiarash Emami2, Yinan Xu2, Hooman Hamedani3, Yi Xin2, Puttisarn Mongkolwisetwara2, Nicholas N. Kuzma2, Per 舓eson4, Peter Magnusson5, Lise Vejby S鴊aard5, Sandra Diaz6, Wilson Miller7, Milton D. Rossman8, Masaru Ishii9, and Rahim R. Rizi2
1Mechanical and Aerospace Engineering, University of California, San Diego, San Diego, CA, United States, 2Radiology, University of Pennsylvania, Philadelphia, PA, United States, 3Radiology, University of Pennsylvania, Philadelphia, Philadelphia, United States, 4Danish Research Centre for Magnetic Resonance, Hvidovre Hospital, Hvidovre, Denmark, 5Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark, 6Department of Clinical Sciences, Malm University Hospital, Malm, Sweden, 7Department of Radiology, University of Virginia, Charlottesville, Virginia, United States, 8Pulmonary, Allergy & Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States, 9Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
Early diagnosis of emphysema is not a possibility with standard clinical tests. Noting the heterogeneity of the disease, CT and increasingly MRI-based imaging techniques have been proposed for this purpose, including measurements of Apparent Diffusion Coefficient (ADC) of respiratory gas. It has been shown that the mean ADC is fairly reproducible marker, which can clearly differentiate emphysematous lungs from healthy lungs. This approach can undesirably mask regional distribution and heterogeneity of abnormalities. This work presents a scalar metric sensitive to regional distributions of gas diffusion in airways while retaining as much of the heterogeneity information as possible.

 
910.   Imaging of localized inert gas washout rates with 3He MRI 
Martin Heiner Deppe1, Xiaojun Peggy Xu1, Steven R. Parnell1, and Jim M. Wild1
1Academic Unit of Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
Inert gas washout is a parameter well-known in lung physiology, but is typically measured only globally at the mouth, hence not containing any information on regional differences. Here we present a method capable of imaging the washout of inert gas from human lungs directly, using hyperpolarized 3He MRI. The resulting data can be analyzed to show the local washout rates for different regions of interest (such as for a traditional core/peel pattern) or on a pixel-by-pixel basis. The method is potentially able to provide important information on diseased lung regions in obstructive lung diseases.

 
911.   Exploring Ventilation and Perfusion Matching in COPD with 3He Ventilation and DCE 1H Perfusion MRI 
Helen Marshall1, Martin H Deppe1, Juan Parra Robles1, Steve R Parnell1, Rob H Ireland1, David Capener1, Sue Hillis1, Smitha Rajaram1, Catherine Billings2, David A Lipson3, Rod Lawson2, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom, 2Respiratory Medicine, University of Sheffield, Sheffield, South Yorkshire, United Kingdom,3GlaxoSmithKline, King of Prussia, PA, United States

 
The combination of 3He ventilation and dynamic contrast enhanced (DCE) 1H perfusion was investigated as a means to assess the matching of ventilation and perfusion (V/Q) in chronic obstructive pulmonary disease (COPD). 3He ventilation, 1H DCE perfusion and anatomical 1H images were acquired from four COPD patients at 1.5T. Ventilated and perfused tissue volumes were calculated as a percentage of total lung volume. Regions of ventilation and perfusion were generally well matched but some areas of V/Q mismatch were also detected. These methods visualise regional V/Q distributions well, and may provide a means of quantitative therapy response evaluation in COPD.

 
912.   Improved Phase-Based Transmitter Calibration for Hyperpolarized-Gas MRI using Shinnar-Le Roux RF Pulses 
Kun Qing1, Grady Wilson Miller2,3, Talissa Altes2, Jaime F. Horta Coelho Mata2, Eduard E. De Lange2, William A. Tobias3, Gordon D. Cates3, James R. Brookeman2, and John Philip Mugler1,2
1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, 2Radiology, University of Virginia, 3Physics, University of Virginia

 
Use of an SLR pulse for phase-based transmitter calibration is predicted to provide more accurate results than those from hard or Fermi pulses, especially for a range of off-resonance values and relatively low peak B1. For transmitter calibration prior to hyperpolarized He3 lung imaging, this approach showed good agreement with an established amplitude-based method. In contrast to the amplitude-based method, the phase-based method uses only a small fraction of the available hyperpolarized magnetization and requires less than 100 ms, and thus could be prepended to a lung-imaging pulse sequence, obviating the need for a dedicated calibration.

 
913.   Sensitivity of transmit coil B1+ to lung inflation in hyperpolarised 3He MRI 
Jim M Wild1, Martin H Deppe1, Salma Ajraoui1, Helen Marshall1, Graham Norquay1, Titus Lanz2, Matthias Behr2, Francesco Padormo3, Juan Parra-Robles1, and Sebastian Kozerke4
1University of Sheffield, Sheffield, Yorkshire, United Kingdom, 2Rapid Biomedical, 3Imperial College, United Kingdom, 4Imaging Sciences, Kings College London

 
Hyperpolarised gas MRI is highly sensitive to RF flip angle (FA) and B1+ homogeneity, thus accurate knowledge of the delivered flip angle and a spatially homogeneous B1+ field are both highly desirable. Chest birdcage coils have been developed for both 3He and 129Xe lung MRI at 1.5T providing homogenous B1+ fields over the lung FOV. In 1H multi-transmit coil imaging of the abdomen at 3T, modulation of the delivered B1+ has been reported as a function of breathing cycle. In this work the effect of lung inflation upon the B1+ field delivered by two 3He chest birdcage coils was investigated at 1.5T and 3T.

 
914.   Quantification of aerosol deposition in the upper airways: A multimodality study 
Mathieu Sarracanie1, Denis Grebenkov2, Soule Coulibaly1, Andrew Martin3, Kyle Hill4, Jose Manuel Perez-Sanchez1, Redouane Fodil5, Lionel Martin1, Emmanuel Durand1, Georges Caillibotte3, Daniel Isabey5, Luc Darrasse1, Jacques Bittoun1, and Xavier Maitre1
1IR4M (UMR8081), Univ Paris-Sud, CNRS, Orsay, France, 2Laboratoire de Physique de la Matiere Condensee (UMR7643), Ecole Polytechnique, CNRS, Palaiseau, France, 3Centre de Recherche Claude Delorme (CRCD), Air Liquide, Les Loges-en-Josas, France, 4Radiology Research Group, Oxford MRI Centre, Oxford University, Oxford, United Kingdom, 5Biomecanique Cellulaire et Respiratoire (U955), IMRB, Inserm, Creteil, France

 
One of the key challenges in the study of health-related aerosols is predicting and monitoring sites of particle deposition in the airways. Recent work in MRI has shed light on techniques to quantify magnetic particles in living bodies by the measurement of associated static magnetic field variations. Dealing with lung MRI, hyperpolarized helium-3 may be used to compensate for the lack of signal in the airways, so as to allow assessment of pulmonary function and morphology. In the present work, aerosol deposition in a mouth-throat phantom measured using helium-3 MRI was correlated with computational fluid dynamics simulations and gamma scintigraphy.

 
915.   Analytical description of long time scale diffusion MRI of the human lung 
Niels Buhl1,2, and Sune N鴕h鴍 Jespersen2
1Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark, 2Center of Functionally Integrative Neuroscience, Aarhus University Hospital, Aarhus, Denmark

 
We present an analytical treatment of long time scale diffusion weighted MRI of the human lung. Diffusion in the airways of the lung is modeled as diffusion on a network of connected line segments, with the relative position of each line segment given by the symmetric branching geometry. Within this model we are able to average the time dependent diffusion coefficient over all airways of the acinar region. The theory is in good agreement with published 3He long time scale measurements, provided the latter may be treated as roughly satisfying the Gaussian phase approximation.

 
916.   Finite Element Simulations of 129Xe Gas Diffusion in Models of Lung Airways 
Juan Parra-Robles1, Steven R Parnell1, Salma Ajraoui1, Xiaojun Xu1, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
Due to their different diffusivities , 3 and 129Xe are sensitive to different length scales of acinar structure. In this work, we investigate short-range 129Xe diffusion in a model of acinar airways using finite element computer simulations. The results suggest that 129Xe short range diffusion experiments may be more sensitive to alveolar structure than 3He, while being less sensitive to branching effects. This may simplify the development of 129Xe-based MR lung morphometry techniques, which could be based on a two compartment model.

 
917.   Finite Element Simulations of Short-Range 3He Diffusion in a Model of Branching Acinar Airways: Implications for In Vivo Lung Morphmetry 
Juan Parra-Robles1, Steven R Parnell1, Salma Ajraoui1, Xiaojun Xu1, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
In this work, we use finite element simulations of diffusion in a model of branching alveolar ducts to investigate in detail the effects of acinar branching structure on short-range 3He diffusion measurements. The obtained results indicate that branching effects have significant influence in 3He diffusivity, even at short diffusion times. The cylinder model theory do not account for significant dependences upon diffusion time, branching geometry and airway length; and further development and validation is required.

 
918.   The Impact of Sub-optimal Pulse Sequence Implementations on XTC MRI Measurements 
Kai Ruppert1, Ching-Ling Teng1, Isabel M Dregely2, Jaime F. Mata1, Talissa A Altes1, G Wilson Miller1, and John P Mugler III1
1University of Virginia, Charlottesville, VA, United States, 2University of New Hampshire, Durham, NH, United States

 
Over the years Xenon polarization Transfer Contrast (XTC) MRI has been implemented in several different variants that conceptually all measure the same quantities. Expanding on recent work by Hrovat et al we investigated how specific XTC MRI sequence implementations and violations of the underlying model assumptions affect the measured quantities using numerical simulations. We found that the delay time between consecutive contrast-generating RF pulse pairs should be held constant and the flip angle should be at least 120 to minimize measurement errors.

Traditional Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the pdf of the poster viewable in the poster hall.
Lung MRI

 
Thursday May 12th
Exhibition Hall  13:30 - 15:30

919.   Magnetic Resonance Elastography of the Lung parenchyma: Correlation of Shear Stiffness with airway opening Pressures 
Yogesh kannan Mariappan1, Arunark Kolipaka1, Rolf D Hubmayr2, Richard L Ehman1, Phillip Araoz1, and Kiaran P McGee1
1Department of Radiology, Mayo Clinic, Rochester, MN, United States, 2Department of Pulmonary and Critical Care medicine, Mayo Clinic, Rochester, MN, United States

 
Magnetic Resonance Elastography (MRE) is being investigated for the quantification of lung parenchymal mechanical properties. Previous small animal experiments using invasive drivers have indicated that 1H based MRE can quantitate lung shear modulus. This technique was extended to an in situ porcine model with a noninvasive driver placed on the chest wall and was tested to measure the change in stiffness as a function of airway opening pressure (Pao) in 10 adult pigs. Shear stiffness increased with increasing Pao, in agreement with theory. It is concluded that in an in situ porcine lung, 1H MRE can quantitate shear stiffness as a function of Pao.

 
920.   Manganese: a new contrast agent for lung imaging? 
Oliviero Gobbo1, Magdalena Zurek2, Frederic Tewes1, Carsten Ehrhardt1, and Yannick Cr閙illieux2
1School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland, 2University of Lyon, CREATIS-LRMN, Lyon, France

 
A new approach for T1-enhancemened rat lung MR imaging, was evaluated. This technique uses a manganese-based contrast agent combined with a very short echo-time radial MRI. Different concentrations of a contrast agent were investigated. A significant signal intensity enhancement was observed in the MnCl2-instilled lung versus control animals. The manganese can be use as an efficient contrast agent for lung MRI.

 
921.   3He and 19F MRI of High Frequency Oscillatory Ventilation (HFOV) 
Laura Schreiber1, Maxim Terekhov1, Uschi Wolf2, Alexander Scholz1, Julien Rivoire1, Rainer K鯾rich3, Janet Friedrich1, Florian Meise1, Sergej Karpuk4, Lars Krenkel5, and Claus Wagner5
1Section of Medical Physics, Johannes Gutenberg University Medical Center, Mainz, Germany, 2Department of Radiology, Johannes Gutenberg University Medical Center, Mainz, Germany,3Maquet GmbH, Rastatt, Germany, 4Institute of Physics, Mainz University, Mainz, Germany, 5Institute of Aerodynamics and Flow Technology, German Aerospace Center, G鰐tingen, Germany

 
MRI during HFOV provides insight into slow and rapid gas transfer processes in the lung. Gas transfer processes are less effective at 10 Hz than at 5 Hz. Results of measurements with hyperpolarized 3He and C4F8 gas give similar results. Differences between the physical characteristics (e.g., density, viscosity, diffusion coefficient) of the contrast gases 3He and C4F8, when compared with those of the respiratory gases O2 and CO2, need to be considered in the interopretation of the results. In conclusion, contrast gas based MRI is a new tool to visualize and analyze intrapulmonary gas transport processes during artifical ventilation.

 
922.   Oxygen-enhanced MRI of the Lungs: Intraindividual Comparison between 1.5 and 3 Tesla 
Olaf Dietrich1, Sven F. Thieme2, Daniel Maxien2, Konstantin Nikolaou2, Stefan O. Schoenberg3, Maximilian F. Reiser1,2, and Christian Fink3
1Josef Lissner Laboratory for Biomedical Imaging, Department of Clinical Radiology, Ludwig Maximilian University of Munich, Munich, Germany, 2Department of Clinical Radiology, Ludwig Maximilian University of Munich, Munich, Germany, 3Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Mannheim, Germany

 
The feasibility of oxygen-enhanced lung MRI (O2-MRI) at 3 Tesla was assessed and compared to 1.5 Tesla. 13 volunteers underwent O2-MRI at 1.5 and 3 Tesla. The mean relative signal enhancement due to oxygen inhalation was 13% ( 5.6%) at 1.5 T and 9.0% ( 8.0%) at 3 T. The regional coefficient of variation was significantly higher at 3 T due to a considerably less homogeneous signal-enhancement distribution. The SNR showed a trend to slightly higher values at 3 T. Oxygen-enhanced pulmonary MRI is feasible at 3 Tesla; however, the signal enhancement is more heterogeneous and slightly lower than at 1.5 T.

 
923.   Quantification of Regional Lung Dysfunction in Distal Airway Disease with Tissue Tracking MRI 
Ding Xia1, Elan J. Grossman1,2, Ke Zhang1, Jian Xu3, Kenneth I Berger4, Roberta M Goldring4, Alexandra Stabile4, Larry Daugherty5, Kellyanne McGorty1, and Qun Chen1
1Center for Biomedical Imaging, Department of Radiology, NYU School of Medicine, New York, New York, United States, 2Department of Physiology and Neuroscience, NYU School of Medicine, New York, New York, United States, 3Siemens Medical Solutions, Malvern, Pennsylvania, United States, 4Department of Medicine, NYU School of Medicine, New York, New York, United States,5Dept of Radiology, University of Pennsylvania, Philadelphia, PA, United States

 
When airway abnormalities are localized only to the distal airways clinical-pathologic correlation between patient illness and lung disease has been difficult to establish. The current study establishes differences in regional lung measurements for patients with known or suspected distal airway dysfunction from controls based on a tissue tracking MRI technique and optical flow method. Our results show that while additional improvement in both data acquisition and data analysis are still required to make the current approach robust, the potential of using tissue tracking MRI for early detection of distal airway appears to be significant.

 
924.   Improved retrospective self-gated human lung imaging using a quasi random sampling scheme 
Stefan Weick1, Philipp Ehses2, Martin Blaimer2, Felix A Breuer2, and Peter M Jakob1,2
1Experimental Physics 5, University of Wuerzburg, Wuerzburg, Bavaria, Germany, 2Research Center for Magnetic Resonance Bavaria (MRB), Wuerzburg, Germany

 
In this work, the human lung was examined under free breathing conditions using the k-space center signal for retrospective respiratory self-gating. The partition and phase encoding of a 3D FLASH sequence were played out in a quasi-random order. The quasi-random sampling results in improved ghost artifact reduction and leads to a very uniformly distribution of missing lines in k-space enabling successful iterative GRAPPA reconstruction. It is shown that the combination of retrospective self-gating with quasi-random sampling is a more robust strategy than the combination with conventional sampling allowing for better image quality in shorter scan time.

 
925.   Ventilation Dependent Blood Volume in Fourier Decomposition 1H Lung Imaging 
Samuel Patz1, and James P. Butler1,2
1Radiology, Brigham and Women's Hospital, Boston, MA, United States, 2Environmental Health, Harvard School of Publich Health, Boston, MA, United States

 
Fourier Decomposition proton MRI for the lung is a promising method that measures proton density changes synchronous with ventilation and heart rate, producing images related to 搗entilation and 損erfusion. There is, however, an additional degree of freedom insofar as blood and tissue volume change independently during ventilation; this has not been considered. Here we analyze the effect of a change in both regional gas volume as well as regional blood volume from a ventilation-only maneuver. We also describe a method to separate the two effects and show this can be used to increase the diagnostic utility of the method.

 
926.   k-t PCA reconstruction for functional lung MRI by Fourier Decomposition 
Grzegorz Bauman1, and Sebastian Kozerke2,3
1Division of Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany, 2Division of Imaging Sciences, King's College London, London, United Kingdom, 3Institute for Biomedical Engineering, University and ETH Zurich, Switzerland

 
As a consequence of the recent shortage of 3He gas for lung imaging studies, alternative methods for the assessment of pulmonary function have received much attention. A very promising approach utilizes time-resolved ultra-short echo time data acquisitions of the native proton signal using a balanced steady-state free-precession (bSSFP) sequence with subsequent image registration and Fourier decomposition to construct perfusion and ventilation-weighted images. The objective of this work is to study the feasibility of k-t undersampling in conjunction with thek-t PCA reconstruction framework for accelerating dynamic bSSFP image acquisition of the lung.

 
927.   Block paradigm optimization for dynamic oxygen-enhanced MRI of the lung 
Olaf Dietrich1, Michael Ingrisch1, Michael Peller1, Konstantin Nikolaou2, and Maximilian F. Reiser1,2
1Josef Lissner Laboratory for Biomedical Imaging, Department of Clinical Radiology, Ludwig Maximilian University of Munich, Munich, Germany, 2Department of Clinical Radiology, Ludwig Maximilian University of Munich, Munich, Germany

 
Several different block paradigms with different numbers of blocks (of oxygen and room air administration) and different block durations have been used in oxygen-enhanced MRI (O2-MRI) of the lung. The purpose of this study was to compare different block paradigms in simulations based on parameters taken from measurements in 11 volunteers to find the optimal design for the evaluation of dynamic O2-MRI data, i.e. for pixelwise fitting of the signal enhancement and the wash-in/out times. Optimal results were obtained with 15 baseline scans (breathing air), followed by 50 scans breathing pure oxygen and by 15 final scans breathing air.

 
928.   Physiological Modelling of Dynamic Oxygen-Enhanced MRI in the Lung: Model Fitting and Parameter Interpretation 
Chris James Rose1,2, Penny Louise Hubbard1,2, Caleb Roberts1,2, Simon S Young3, Josephine H Naish1,2, and Geoffrey J Parker1,2
1The University of Manchester Biomedical Imaging Institute, The University of Manchester, Manchester, Greater Manchester, United Kingdom, 2Manchester Academic Health Science Centre, The University of Manchester, Manchester, Greater Manchester, United Kingdom, 3AstraZeneca R&D Charnwood, Loughborough, Leicestershire, United Kingdom

 
Voxel-wise measurements of ventilation-to-perfusion ratio (V/Q) in the lung can be made using oxygen-enhanced MRI (OE-MRI). Patients are dynamically imaged as they switch from breathing medical air to an elevated concentration of oxygen. The change in partial pressure of oxygen over time is modelled in terms of three parameters, v, q, and λB. We consider fitting this model to data and study the topology of the sum of squared differences (SSD) function. We demonstrate a valley in the SSD function of optimal v and q values satisfying v/q=V/Q, and show that v andq should not be interpreted independently.

 
929.   Longitudinal and non-invasive assessment of emphysema evolution in a murine model using proton MRI 
Magdalena Zurek1, Laurent Boyer2, Philippe Caramelle2, Jorge Boczkowski2, and Yannick Cr閙illieux1
1University of Lyon, CREATIS-LRMN, Lyon, France, 2INSERM U955, Paris, France

 
Tissue density losses and microstructural changes of the lung parenchyma present in emphysema disease can affect both, the MR image intensity and T2* values. Using an ultra-short echo-time (UTE) sequence, signal intensity and T2* changes were track in emphysema disease progression along an 8-weeks longitudinal study in elastase-challenged mice. The MR findings were confirmed by histology. The MR results are in good agreement with published CT observations and with predictions from a physical model. This technique is readily suitable for routine drug testing in experimental MR lung research of emphysema and can be transferred to human studies.

 
930.   Reproducibility Assessment of High Resolution Imaging of Alveolar Oxygen Tension in Human Subjects 
Hooman Hamedani1, Kiarash Emami1, Stephen J. Kadlecek1, Yinan Xu1, Yi Xin1, Puttisarn Mongkolwisetwara1, Amy Barulic1, Nicholas N. Kuzma1, Peter Magnusson2, Lise Vejby S鴊aard2, Sandra Diaz3, Per 舓eson2, Milton D. Rossman4, Masaru Ishii5, G. Wilson Miller6, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark,3Department of Clinical Sciences, Malm University Hospital, Malm, Sweden, 4Pulmonary, Allergy & Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States,5Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, MD, United States, 6Radiology, University of Virginia, Charlottesville, Virginia, United States

 
We have performed a reproducibility assessment for a newly improved high-resolution scheme for alveolar oxygen tension. Our results show that this PAO2 measurement by the HP 3He MRI is a reasonable approximation of the physiological PAO2 and is also reproducible.

 
931.   An Improved Scheme for a Robust High Resolution Measurement of Alveolar Oxygen Tension in Human Lungs 
Hooman Hamedani1, Kiarash Emami1, Stephen J. Kadlecek1, Yinan Xu1, Yi Xin1, Amy Barulic1, Puttisarn Mongkolwisetwara1, Nicholas N. Kuzma1, Peter Magnusson2, Lise Vejby S鴊aard2, Sandra Diaz3, Per 舓eson2, G. Wilson Miller4, Milton D. Rossman5, G. Wilson Miller6, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark,3Department of Clinical Sciences, Malm University Hospital, Malm, Sweden, 4Radiology, University of Virginia, Charlottesville, VA, United States, 5Pulmonary, Allergy & Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States, 6Department of Radiology, University of Virginia School of Medicine, Charlottesville, VA

 
A new higher-resolution multi-slice scheme for measuring regional partial pressure of oxygen in the lungs via HP 3He MRI is presented. This new scheme is based on eliminating the delay time needed to differentiate the effects of oxygen and RF pulses, instead making use of two interleaved back-to-back acquisitions for each slice. The resulting PAO2 errors are decreased by a factor of ~3 in this new scheme.

 
932.   Imaging Regional Heterogeneity of Pulmonary Oxygen Tension as a Diagnostic Tool for Obstructive Lung Diseases 
Yinan Xu1, Hooman Hamedani1, Kiarash Emami1, Stephen J. Kadlecek1, Yi Xin1, Puttisarn Mongkolwisetwara1, Amy Barulic1, Nicholas N. Kuzma1, Per 舓eson2, Peter Magnusson3, Lise Vejby S鴊aard3, Sandra Diaz4, Milton D. Rossman5, Wilson Miller6, Masaru Ishii7, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Danish Research Centre for Magnetic Resonance, Hvidovre Hospital, Hvidovre, Denmark, 3Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark, 4Department of Clinical Sciences, Malm University Hospital, Malm, Sweden, 5Pulmonary, Allergy & Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States, 6Department of Radiology, University of Virginia, Charlottesville, Virginia, United States, 7Otolaryngology朒ead & Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
New method for quantifying the lung heterogeneity from the HP 3He MRI measurements of alveolar partial oxygen pressure pO2 is tested in this human study. The method allows us to differentiate healthy smokers and COPD patients from non-smokers based on the difference in their lung homogeneity.

 
933.   Pulmonary T2* dependence on the lung volume: preliminary results 
Iga Muradyan1, Mirko Hrovat2, Mikayel Dabaghyan3, James Butler4, Hiroto Hatabu3, and Samuel Patz3
1Brigham and Women's Hospital, Boston, MA, United States, 2Mirtech, Inc., 3Brigham and Women抯 Hospital, 4Harvard School of Public Health

 
Breathing is accompanied with alveolar shape changes: at lower lung volumes alveoli are more spherical, while at higher lung volumes they assume more polyhedral shape. Such changes can affect the field homogeneity in the tissue due to air-tissue susceptibility difference. We hypothesized that lung volume will affect pulmonary T2* and measured it at 3 lung volumes: near RV, FRC and TLC. The signal behavior with TE suggested that T2* does not follow mono-exponential function and more sophisticated model is necessary for proper T2* estimation. The lung data suggests a small increase of T2* with lung volume.

 
934.   Fast T2 Mapping of the Lung within one Breathhold using Radial TSE Acquisition and PCA aided Image Reconstruction 
Michael V鰈ker1, Felix Breuer1, Philipp Ehses1, Simon Michael Triphan1, Martin Blaimer1, and Peter Michael Jakob1,2
1Research Center for Magnetic Resonance Bavaria (MRB), W黵zburg, Bavaria, Germany, 2Department of Experimental Physics 5, University of W黵zburg, Germany

 
A strategy for fast T2 relaxometry of the human lung is presented. Using radial TSE data acquisition, artifact-free separation of different T2 contrasts is possible by means of a novel iterative reconstruction technique based on Principal Component Analysis (PCA). It is shown that multislice T2 maps can be obtained in one single breathhold of 12s.

 
935.   Accelerating pixel-by-pixel non-linear curve fitting using parallel computation on graphic processing units: Application to pulmonary perfusion mapping. 
Wei-Min Tseng1, Teng-Yi Huang1, Yi-Ru Lin2, and Ming-Ting Wu3
1Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan, 2Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan, 3Department of Radiology, Kaohsiung Veterans General Hospital, Kao-Hsiung, Taiwan

 
This study attempts to accelerate pixel-by-pixel non-linear fitting with modern parallel computation on graphic processing units. Levenberg-Marquardt algorithm was implemented into GPU-based toolbox compatible to MATLAB environment. The time-intensity curve of each pixel is distributed to each thread of parallel computation. The four-GPU system can compute up to 960 curve-fitting in parallel. The toolbox was tested with a 7-slice pulmonary DCE perfusion dataset to reconstruct the pulmonary blood volume maps. The proposed GPU-fitting toolbox reduced the total computation time from ~20 minutes to ~0.5 minute.

 
936.   Qualitative and quantitative lung perfusion imaging of children with congenital diaphragmatic hernia at 3T: initial results 
Frank G Zoellner1, Katrin Zahn2, Thomas Schaible3, Stefan O Schoenberg4, Lothar R Schad1, and K W Neff4
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, 2Dept. of Pediatric Surgery, University Medical Center Mannheim, Heidelberg University, Mannheim, 3Dept. of Pediatrics, University Medical Center Mannheim, Heidelberg University, Mannheim, 4Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany

 
In congenital diaphragmatic hernia (CDH), lung hypoplasia and secondary pulmonary hypertension are the major causes of death. To the best of our knowledge, quantitative perfusion imaging of the lung in CDH has not been utilized so far. Here, we investigated whether DCE-MRI of the lung in survivors after CDH-repair at 3.0T is feasible. Ipsilateral lung hypoplasia with reduced perfusion is reflected by significant lower rPBF values (34.318 ml/100ml/min) compared to the contralateral lung (89.727 ml/100ml/min). In conclusion, DCE-MRI of the lung in CDH can help characterizing lung hypoplasia initially and in long-term follow-up of children after CDH-repair.

 
937.   Pulmonary Arterial Hypertension: First-Pass Contrast Bolus Kinetics Contain Information on RV Function, Remodeling, and Lung Resistance 
Jens Vogel-Claussen1,2, Jan Skrok2, Monda Shehata2, David A Bluemke3, Reda Girgis2, and Paul M Hassoun2
1T黚ingen University, T黚ingen, BW, Germany, 2Johns Hopkins University, Baltimore, MD, United States, 3National Institutes of Health

 
Predictors of survival in patients with pulmonary arterial hypertension (PAH) include right ventricular (RV) cardiac index (RVCI), mean pulmonary arterial pressure (mPAP), and pulmonary vascular resistance (PVR). Our hypothesis was that first-pass contrast bolus kinetics, such as cardiopulmonary transit time (PTT), left ventricular (LV) full-width-half-maximum (FWHM), and LV time-to-peak are related to these parameters. In our MRI study we showed that in patients with known or suspected PAH, first-pass bolus kinetics are closely related to pulmonary hemodynamics and RV dysfunction. Right-to-left-ventricular PTT is predicted by RV cardiac function and biventricular remodeling; time-to-peak and FWHM are associated with pulmonary vascular resistance.

Traditional Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the pdf of the poster viewable in the poster hall.
NSF & Contrast Media

 
Monday May 9th
Exhibition Hall  14:00 - 16:00

938.   Incidence of Immediate Gadolinium Contrast Media Reactions 
Martin R Prince1,2, Honglei Zhang1, Zhitong Zou1, Ronale B Staron2, and Paula W Brill1
1Radiology, Weill Cornell Medical College, New York, NY, United States, 2Radiology, Columbia College of Physicians and Surgeons, New York, NY, United States

 
GBCA adverse events reported in 94 patients over 10 years were analyzed to determine their incidence. Immediate AE rates were 0.2, 0.5, 1.2 and 3.3 per 1,000 injections for gadodiamide, gadopentetate dimeglumine, gadobenate dimeglumine and gadoteridol. Gadobenate dimeglumine had more severe reactions (3 arrests, one of whom died). Abdominal MRI had the highest rates of AE, 0.013% compared to brain (0.0045%) or spine (0.0034%). From 2004 to 2009 FDA received reports on 40 GBCA US deaths unrelated to NSF with an incidence of < 1 death per million (40 deaths/51 million GBCA administrations) indicating GBCA are extraordinarily safe.

 
939.   Gadolinium exposure before or after liver transplantation: No excess risk of nephrogenic systemic fibrosis (NSF)? 
Elise Eva Saddleton1, Anne Laumann2, Dennis P. West2, Steven M. Belknap3, Brenda Schmitz1, Beatrice J. Edwards3, Nicole Papariello2, Michael I. Abecassis4, and Frank H. Miller1
1Radiology, Northwestern University, Chicago, IL, United States, 2Dermatology, Northwestern University, Chicago, IL, United States, 3Medicine, Northwestern University, Chicago, IL, United States, 4Transplant Surgery, Northwestern University, Chicago, IL, United States

 
The FDA抯 2007 warning describing the risk of nephrogenic systemic fibrosis (NSF) with gadolinium administration in patients with acute renal insufficiency of any severity due to hepatorenal syndrome or in the perioperative liver transplantation period poses a significant problem for practitioners who routinely use magnetic resonance imaging (MRI) to evaluate liver transplant patients. The warning appears to have been based on a few patients who received gadodiamide. We evaluated the use of gadolinium-based contrast agents (GBCAs) and the presence of NSF in a large liver transplant center. We hypothesized no increased risk of NSF in the perioperative liver transplant period beyond that associated with severe renal disease.

 
940.   Nephrogenic Systemic Fibrosis: Portrait in the Medical Literature 
Gianpaolo Pirovano1, Cindy Schultz2, John R Parker2, Miles A Kirchin3, and Alberto Spinazzi1
1Worldwide Medical Affairs, Bracco Diagnostics Inc., Princeton, NJ, United States, 2Medical Communications, Bracco Diagnostics Inc., Princeton, NJ, United States, 3Medical Communications, Bracco Imaging, Milan, Italy

 
Following a comprehensive literature search, 133 articles were identified, reporting 705 unique cases of NSF from 19 countries. 605 cases (85.8%) were biopsy-proven. Most cases involved patients with Stage 4 or 5 CKD, although in 14 cases the patient suffered from acute renal failure. Patients receiving only Omniscan or Magnevist accounted for 93.3% of reported NSF cases. The most commonly administered gadolinium doses were 0.2-0.29 mmol/kg. In most cases, symptoms appeared 1-3 months after the last administration of gadolinium contrast. Importantly, no cases with an onset after 2007 were identified, suggesting changes in practice patterns have largely eliminated this disease.

 
941.   Combined off-resonance imaging and relaxation in the rotating frame for positive contrast imaging of infection in a murine burn model testing a novel anti-infective compound 
Valeria Righi1,2, Melissa Starkey3, Jianxin He3, George Dai2, Vitaliano Tugnoli4, Laurence G. Rahme3, Ronald G. Tompkins5, and Aria A. Tzika1,2
1Department of Surgery, NMR Surgical Laboratory, MGH and Shriners Burn Institute, Harvard Medical School, Boston, MA, United States, 2Department of Radiology, Athinoula A. Martinos Center of Biomedical Imaging, Boston, MA, United States, 3Department of Surgery, Molecular Surgery Laboratory, MGH and Shriners Burn Institute, Harvard Medical School, Boston, MA, United States,4Departement of Biochemistry, University of Bologna, Bologna, Bologna, Italy, 5Department of Surgery, MGH and Shriners Burn Institute, Harvard Medical School, Boston, MA, United States

 
We demonstrated the feasibility to monitor inhibition of infection in a clinically relevant mouse model of infection after burn. Our results show that our novel compound M50 attenuates the signals coming from macrophages that accumulate at the infection site and thus support the compound抯 anti-infective action. These results may have direct implications in the longitudinal monitoring of infection, and open perspectives for testing our novel anti-virulence compounds.

 
942.   Development of Nanoparticle-Based Magnetic Resonance Colonography 
Jihong Sun1,2, Weiliang Zheng1, Hong Yuan3, Tao Wu1, Xiaoming Yang1,2, and Shizheng Zhang1
1Radiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China, People's Republic of, 2Radiology, University of Washington School of Medicine, Seattle, WA, United States,3College of Pharmaceutical Science, Zhejiang University, Hangzhou, Zhejiang, China, People's Republic of

 
The aim of this study was to develop a novel nanoparticle-based magnetic resonance (MR) colonography technique, which enabled us to generate contrast-enhanced MRI of the colonic walls via transrectal administration of colonic-absorbable, Gd-DTPA-loaded solid lipid nanoparticles (SLNs). In vivo MRI demonstrated bright enhancement of colonic walls with decreased T1 relaxation times in all mice treated by transrectal infusions of Gd-SLNs, which was confirmed by subsequent histologic correlation. This study establishes the “proofs-of-principle” of a new imaging technique ─ nanoparticle-based MR colonography.

Traditional Posters : Body (Non-Cancer) Imaging
Click on to view the abstract pdf and click on to view the pdf of the poster viewable in the poster hall.
Body - Animal Models

 
Tuesday May 10th
Exhibition Hall  13:30 - 15:30

943.   1H-MRS can be used to investigate creatine metabolism in multiple organs within a single examination in the mouse 
Kiterie Maud Faller1, Craig A Lygate1, Stefan Neubauer1, and Jurgen E Schneider1
1Cardiovascular medicine, University of Oxford, Oxford, Oxfordshire, United Kingdom

 
Creatine has a protective effect against ischemia in tissues with high energy demand such as the brain or the heart. 1H-MRS is the only technique available to measure creatine non-invasively. As the metabolism of creatine is organ-specific, spectra from different organs need to be acquired to get a general view of creatine metabolism in the mouse. We showed that creatine can be measured within a single anaesthesia in three different organs (brain, cardiac and skeletal muscles) with a simple set-up and with a good accuracy. This allows us to perform longitudinal studies in mice with global changes in creatine levels.

 
944.   Characterization of Liver Fibrosis by 1H- and 31P-MRS in CCl4-treated Rats 
Yunjung Lee1, Hyungjoon Noh1, Keunhyung Kang1, Ok-Hee Kim1, Byung-Chul Oh1, and Hyeonjin Kim2
1Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, Korea, Republic of, 2Radiology, Seoul National University Hospital, Seoul, Korea, Republic of

 
Liver fibrosis was characterized in CCl4-treated rats by using both 1H- and 31P-MRS, and the potential diagnostic efficacy of the technique was evaluated. The differentiation between the three animal groups of control, F1-2 and F3-4 in this study was achieved only if the combination of the 1H- and 31P-MRS measures was used. Therefore, our study demonstrates the advantage and feasibility of using both 1H- and 31P-MRS techniques in the assessment of liver fibrosis in vivo.

 
945.   A new technique for the detection of liver damage by evaluation of impaired exocytotic activity of Kupffer cells; an experimental study of gadolinium chloride-induced liver injury in rats 
Toshihiro Furuta1,2, Masayuki Yamaguchi1, Ryutaro Nakagami1,3, Masaaki Akahane2, Manabu Minami4, Kuni Ohtomo2, and Hirofumi Fujii1
1Functional Imaging Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, Japan, 2Department of Radiology, The University of Tokyo Hospital, Tokyo, Japan, 3Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan, 4Department of Radiology, Tsukuba University Hospital, Tsukuba, Japan

 
We propose a new technique for the detection of liver damage based on the impaired exocytotic activity of Kupffer cells (KCs) using SPIO-enhanced MRI, in which SPIO was administered in advance of the liver damage. Our hypothesis is that if KCs are labeled with SPIO prior to liver damage, the exocytotic activity of KCs could be evaluated by the delayed recovery of hepatic signals suppressed by SPIO on T2*-weighted MRI. Our preliminary data using an animal model, in which KCs were damaged by the administration of gadolinium chloride, supported our hypothesis.

 
946.   Imaging of Hepatic Steatosis and Hyperpolarized Carbon Metabolism at 14T - Applications to a Murine Model of Non-Alcoholic Fatty Liver Disease 
Andrew G. Taylor1, Kayvan Keshari1, Robert Bok1, Subramaniam Sukumar1, Aliya Qayyum1, and John Kurhanewicz1
1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States

 
Non-Alcoholic Fatty Liver Disease (NAFLD) is a very common cause of chronic liver disease, however understanding of metabolic abnormalities and prognostic indicators in NAFLD is limited. In vivo studies of hepatic metabolism in a mouse model of NAFLD were performed at 600MHz using copolarized [1-13C]-pyruvate and 13C-urea. An interleaved fat- and water-sensitive sequence, used to monitor disease progression, correlated well with extent of steatosis on subsequent histology. No significant change in hepatic pyruvate metabolism was identified in NAFLD mice relative to control, consistent with published work suggesting hypermetabolism in this model results from increased lipid flux through β-oxidation.

 
947.   Comparison of Gd-DTPA and Gd-BOPTA for studying renal perfusion and filtration 
Mike Notohamiprodjo1, Michael Pedersen2, Christian Glaser3,4, Andreas D Helck3, Klaus-Peter Lodemann5, Bente Jespersen6, Michael Fischereder7, Maximilian F Reiser3, and Steven P Sourbron8
1Department of Clinical Radiology, University Hospitals Munich, Munich, Bavaria, Germany, 2MR Research Centre, Aarhus University Hospital, 3Department of Clinical Radiology, University Hospitals Munich, 4Department of Radiology, NYU Langone Medical Center, 5Bracco Imaging Germany, 6Department of Nephrology, Aarhus University Hospital, 7Department of Nephrology, University Hospitals Munich, 8Division of Medical Physics, University of Leeds

 
Protein binding of MR contrast agents may cause a systematic error in perfusion- and filtration parameters measured with MR-Renography. The purpose of this study was to measure the magnitude of this error using a dual-agent protocol in a pig model. The findings of the performed experiments show that perfusion parameters of both agents are comparable, whereas GFR is underestimated with Gd-BOPTA due to the dependence of relaxivity on protein content. Hence GFR cannot be measured with protein-bound contrast agents, but the proposed dual-agent protocol may produce new functional indices measuring protein filtration.

 
948.   MRI Biomarkers for Monitoring Progression in CKD: Preliminary Experience in a Reversible UUO Mouse Model 
Muhammad E Haque1, Tammy Franklin1, Ujala Bokhary1, Liby Mathew2, Anthony Chang3, Tipu Puri2, and Pottumarthi V Prasad1,4
1Radiology, NorthShore University HealthSystem, Evanston, IL, United States, 2Nephrology, University of Chicago, Chicago, IL, 3Pathology, University of Chicago, Chicago, IL, 4Radiology, University of Chicago, Chicago, IL, United States

 
Current clinical markers to assess the severity of chronic kidney disease (CKD) and its progression are limited and inadequate. It is highly desirable to develop new non-invasive markers that could reliably monitor the progression of disease over time. Renal hypoxia and fibrosis are two known hallmarks of CKD. Here we have used a reversible unilateral ureteral obstruction model in mice to evaluate BOLD and diffusion MRI measurements to monitor progression of CKD We also evaluated genetic variability between two strains of mice. These methods may prove valuable in better understanding the natural progression of CKD and in evaluating novel interventions.

 
949.   MRI Characterization of Pathophysiological Changes in a Mouse Model of Acute Kidney Injury (AKI) 
Andreas Pohlmann1, Lajos Marko2,3, Babette Wagenhaus1, Uwe Hoff4, Erdmann Seeliger5, Dominik N Mueller2,3, and Thoralf Niendorf1
1Berlin Ultrahigh Field Facility, Max Delbrueck Center for Molecular Medicine, Berlin, Germany, 2Max Delbrueck Center for Molecular Medicine, Berlin, Germany, 3Experimental and Clinical Research Center, Charit University Medicine, Berlin, Germany, 4Clinic for Nephrology, Charit University Medicine, Berlin, Germany, 5Institute of Vegetative Physiology, Charit University Medicine, Berlin, Germany

 
Renal medullary hypoperfusion and hypoxia play a key role in acute kidney injury (AKI). Established methods to assess renal hemodynamics and oxygenation in vivo are limited to short time periods and/or probing only small regions. MRI allows assessing tissue oxygenation and oedema for the entire kidneys, repeatedly. We demonstrated the feasibility of characterizing alterations in renal hemodynamics and oxygenation under (patho)physiological conditions such as renal ischemia/reperfusion injury (I-R). Kidneys that underwent I-R showed strong changes of contrast (T2w) in the cortex and medulla. T2*-mapping showed equally dramatic changes quantitatively.

 
950.   Real-time Multi-slice MRI of Renal Filtration in the Mouse 
Amir Moussavi1, Martin Uecker1, Tilman Johannes Sumpf1, Roland Tammer1,2, Jens Frahm1, and Susann Boretius1
1Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut fuer biophysikalische Chemie, Goettingen, Germany, 2DFG Research Center for Molecular Biology of the Brain (CMPB), Goettingen, Germany

 
To avoid the necessity of respiratory gating, abdominal MRI of the mouse requires short acquisition times. The combination of highly undersampled radial FLASH with a nonlinear inverse image reconstruction algorithm allowed for movies with a temporal resolution of 70 ms per image. Accordingly, dynamic contrast-enhanced studies of the mouse kidney could be performed at high spatial and temporal resolution. Moreover, the approach facilitated the simultaneous coverage of both kidneys by multiple sections.