Lung/Mediastinum/Hyperpolarized Gas Imaging

Wednesday, 3 June 2015

Yoshiharu Ohno^1,2, Masao Yui³, Cheng Ouyang⁴, Mitsue Miyazaki⁴, Hisanobu Koyama⁵, Shinichiro Seki⁵, Katsusuke Kyotani⁶, Yoshiko Ueno⁵, Takeshi Yoshikawa^1,2, Sumiaki Matsumoto^1,2, and Kazuro Sugimura^5
1Advanced Biomedical Imaging Research, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, ²Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, ³Toshiba Medical Systems Corporation, Tochigi, Japan, ⁴Toshiba Medical Research Institute USA, IL, United States, ⁵Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, ⁶Center for Radiology and Radiation Oncology, Kobe University Hospital, KObe, Hyogo, Japan

Chemical exchange saturation transfer (CEST) imaging is suggested as new technique and one of the MR-based molecular imaging techniques. However, no major reports have been published for evaluating clinical utility of CEST imaging in thoracic oncology patients. We hypothesized that newly developed CEST imaging is possible to evaluate thoracic nodule and mass, and play as new diagnostic tool in routine clinical practice. The purpose of this study was to determine the capability of CEST imaging for characterization of thoracic nodule and mass, and evaluate a potential as a new MR-based molecular imaging method in thoracic oncology.

Sarah Svenningsen^1,2, Fumin Guo^1,3, Roya Etemad-Rezai⁴, David G McCormack⁵, and Grace Parraga^1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, ²Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, ³Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada, ⁴Department of Medical Imaging, The University of Western Ontario, London, Ontario, Canada, ⁵Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada

MRI provides a way to generate a rich mosaic of regional ventilation measurements that enable regional quantification of pulmonary functional abnormalities and their response to therapy. Until now, respiratory intermediate endpoints have relied on global lung function measurements, although in general respiratory disease is regionally heterogeneous. Accordingly, our objective was to provide a way to regionally quantify lobar lung ventilation measurements in bronchiectasis patients using an automated registration-segmentation pipeline. For patients with localized bronchiectasis, regional measurements of ventilation were significantly worse in lobes with CT evidence of bronchiectasis. These regional measurements provide a novel intermediate endpoint for therapy studies.

Simon MF Triphan^1,2, Bertram J Jobst¹, Felix A Breuer², Mark O Wielpuetz¹, Claus Peter Heussel³, Hans-Ulrich Kauczor¹, Juergen Biederer^1,4, and Peter M Jakob^2,5
1Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany, ²Research Centre Magnetic Resonance Bavaria e.V., Wuerzburg, Germany, ³Dept. of Radiology, Thoraxklinik Heidelberg, Heidelberg, Germany, ⁴Radiologie Darmstadt, Darmstadt, Germany, ⁵Experimental Physics 5, University of Wuerzburg, Wuerzburg, Germany

Lung T₁ was measured using a multi-echo inversion recovery UTE sequence at TEs between 70μs and 2.3ms in 10 healthy volunteers. A significant increase of average measured T₁ with TE was observed, with mean values of 1051ms and 1408ms for the shortest and longest TE. This TE-dependence is assumed to reflect separate blood and extravascular components in the lung that exhibit both different T₁ and T₂* times. In consequence, comparison of lung T₁ values requires consideration of TE. This effect may also be exploited to gain information on these compartments.

Andrea Bianchi¹, Oliviero G. Gobbo², Sandrine Dufort³, Lucie Sancey⁴, François Lux⁴, Olivier Tillement⁴, Jean-Luc Coll³, and Yannick Crémillieux^1
1Centre de Résonance Magnétique des Systèmes Biologiques, University of Bordeaux, Bordeaux, Bordeaux, France, ²Trinity College Dublin, School of Biochemistry and Immunology, Dublin, Ireland, ³IAB-INSERM, UJF U 823, Grenoble, France, ⁴ILM UMR 5306, University Lyon 1, Lyon, France

The small hydrodynamic diameter, high water solubility, large availability on the market and the reduced cost of manganese (Mn2+) compounds make MEMRI a good candidate for oncological applications. We present here for the first time an in vivo MRI study of lung cancer detection in tumor-bearing mice using very low doses of intratracheally- and intravenously- administered manganese chloride (MnCl2). The localization of the tumors was validated against bioluminescence imaging (BLI) and histology. Due to the possible neurotoxicity of the manganese, the accumulation of MnCl2 in the brain was evaluated using MRI.

Jose L Ulloa^1,2, Alexandra R Morgan^1,2, and Geoff JM Parker^1,2
1Bioxydyn Ltd, Manchester, United Kingdom, ²Centre for Imaging Sciences, University of Manchester, Manchester, United Kingdom

Dynamic oxygen-enhanced MRI (dOEMRI) provides imaging biomarkers of regional lung ventilation and perfusion. However, time sampling constraints have limited it to single slice imaging. In this work, we evaluate a novel quantitative whole lung 3D dOEMRI protocol based on a standard single-shot 3D MPRAGE sequence. Sequence parameters were optimised to maximise contrast in the lung when switching from air to O₂. The protocol enables the capture of the whole lung volume within a breathing cycle. Six healthy volunteers were scanned twice, one week apart. The protocol shows reproducible T1 measurements and allows characterisation of dynamic ΔpO₂.

Andrea Bianchi¹, Marta Tibiletti², David Kind¹, Andrea Vögtle¹, Michael Neumaier¹, Thomas Kaulisch¹, Volker Rasche², and Detlef Stiller^1
1Targeting Discovery Research, In vivo imaging laboratory, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Baden-Württemberg, Germany, ²Core Facility Small Animal MRI, Ulm University, Baden-Württemberg, Germany

One of the main open issues in pre-clinical lung imaging is how to provide full coverage of the lung while keeping good image quality in a reasonable acquisition time, with both high spatial resolution and significant signal-to-noise ratio (SNR) in lung parenchyma. We propose here for the first time the investigation of an emphysema model in rats using a ZTE sequence and a thorax-optimized phased-array coil. The results were validated against the gold-standard micro-CT and the standard measurement of T2* using ultra-short echo time (UTE) MRI.

Flavio Carinci^1,2, Felix A. Breuer¹, and Peter M. Jakob^1,2
1Research Center Magnetic Resonance Bavaria (MRB), Würzburg, Bayern, Germany, ²Department of Experimental Physics 5, University of Würzburg, Würzburg, Bayern, Germany

The alveolar size is a parameter of paramount importance in the lung, since it could help to develop a better understanding of respiratory dynamics and to detect microstructural injuries. Here, a novel approach based on proton MRI is proposed, which allows for the quantification of the alveolar size in vivo, by exploiting the transverse relaxation enhancement due to water diffusion through the internal magnetic field gradients of the lung. To this end, maps of the transverse relaxation enhancement are acquired. Additionally, proton density images are used to correct for variations of the air fraction with inflation. Maps of the alveolar diameter are calculated from a combination of the two. Experiments performed on healthy volunteers show similar values in expiration and inspiration, with a mean value within the lung of about 230μm. This is in good agreement with previous reports, as well as with the alveolar recruitment theory.

Crystal E. Harrison¹, Masaya Takahashi¹, Robert E. Lenkinski¹, and Ananth J. Madhuranthakam^1
1Radiology and Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States

Chronic obstructive pulmonary disease (COPD) disrupts pulmonary ventilation and perfusion. Oxygen-Enhanced (OE) MRI can probe pulmonary ventilation with inhaled molecular oxygen as an exogenous T₁ contrast agent. One of the primary challenges of lung imaging is the short T₂* of the lung tissue. Ultrashort echo time (UTE) radial acquisitions minimize this signal loss and SNR at short TE is higher for 3 T than 1.5 T as is the change in T₁ due to inhaled O₂. The purpose of the current study is to demonstrate the feasibility of performing the OE-UTE ventilation mapping in human subjects at 3 T.

Neville D Gai¹, Robert Evers¹, Harsh Agarwal², Ashkan Malayeri¹, and David Bluemke^1
1Radiology & Imaging Sciences, NIH, Bethesda, MD, United States, ²Philips Research N.A., Briarcliff Manor, NY, United States

Clinical MR lung imaging is being increasingly done to avoid ionizing radiation especially in longitudinal studies. In this work, we optimize a 3D stack of stars acquisition to perform high SNR complete lung imaging in a single breath-hold. Ten consecutive volunteers were scanned on a 3T scanner for axial and coronal breath-hold images. The images were analyzed for SNR in lung parenchyma. Results indicate the suitability of the technique for robust lung imaging in a clinical setting.

Orso Pusterla¹, Grzegorz Bauman¹, Gregor Sommer², Christoph Jud³, Philippe C. Cattin³, and Oliver Bieri^1
1Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland, ²Clinic of Radiology and Nuclear Medicine, Department of Radiology, University of Basel Hospital, Basel, Switzerland, ³Medical Image Analysis Center (MIAC), University of Basel Hospital, Basel, Switzerland

Ultra-fast balanced Steady-State Free Procession (ufSSFP) pulse sequence was proposed for morphological and functional lung imaging, offering short acquisition times with exceptional SNR and CNR. In this work, it was demonstrated the feasibility of three-dimensional oxygen-enhanced (OE) lung MRI with ufSSFP in healthy volunteers taking into account a possible bias in OE contrast images due to volume-dependent signal intensity modulations. The proposed technique has the potential to be used for subjects with lung diseases.

Laura C Bell¹, Peter Bannas², Kevin M Johnson², Grzegor Bauman³, Sean B Fain^1,2, Thomas M Grist^1,2, and Scott K Nagle^1,2
1Department of Medical Physics, University of Wisconsin - Madison, Madison, Wisconsin, United States, ²Department of Radiology, University of Wisconsin - Madison, Madison, Wisconsin, United States, ³Department of Radiology, University of Basel Hospital, Basel, Switzerland

Conventional dynamic contrast-enhanced MR sequences sacrifice spatial resolution for high temporal resolution in order to visualize perfusion. This work utilizes a single breath-held 3D radial UTE acquisition with both high spatial (to visualize filling defects) and temporal resolution (to visualize perfusion defects) to identify pulmonary embolism in an animal model. This technique performed very well against computed tomography angiography, collected as a reference. Additionally, the reader had higher confidence in diagnosing defects with the 3D radial acquisition due to better image quality when compared to a typical 3D Cartesian acquisition.

Hongchen Wang¹, Catherine Sebrié¹, Sébastien Judé², Anne Maurin², Stéphanie Rétif³, Marilyne Le Mée³, Rose-Marie Dubuisson¹, Georges Willoquet¹, Khaoula Bouazizi-Verdier¹, Luc Darrasse¹, Geneviève Guillot¹, Xavier Maître¹, and Ludovic de Rochefort^1
1Imagerie par Résonance Magnétique Médicale et Multi-Modalités (UMR8081) IR4M, CNRS, Univ. Paris-Sud, Orsay, France, ²Centre de Recherches Biologiques CERB, Baugy, France, ³Centre d'Imagerie du Petit Animal CIPA, CNRS-TAAM UPS44, Orléans, France

Asthma and emphysema are chronic respiratory diseases, which are commonly treated by inhalation of nebulized drugs. Aerosol deposition patterns are difficult to predict as they highly depend on airway geometry, breathing parameters, aerosol and gas properties. In vitro and in vivo studies have been performed to better understand deposition mechanisms and to improve inhaled drug delivery. Here, 3D UTE-MRI combined with spontaneous nose-only inhalation of aerosolized Gd-DOTA was implemented at 1.5T to map the distribution of aerosol deposition and to characterize the aerosol lung clearance in asthmatic and emphysematous rats. This functional lung imaging may be transferred to the clinic.

Gregory Paulin^1,2, Alexei Ouriadov^1,2, Khadija Sheikh^1,2, David G McCormack³, and Grace Parraga^1,2
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

Diffusion-weighted noble gas pulmonary MRI provides in vivo images with contrast uniquely sensitive to molecular displacement at cellular and sub-cellular length scales. We estimated the external airway radius and internal airway radius of alveoli to evaluate potential differences in acinar duct morphometries in healthy older never-smokers using a multi-slice 2D gradient echo diffusion-weighted sequence. Preliminary results show that MRI measurements of lung morphometry in older never-smokers were elevated compared to previous results reported in younger never-smokers. These findings are compatible with senile emphysematous changes to healthy lung parenchyma that accompanies aging.

Maya Khalifé¹, Hongchen Wang¹, Lizheng Qiu¹, Catherine Sebrié¹, and Ludovic De Rochefort^1
1IR4M (Imagerie par Résonance Magnétique Médicale et Multi-Modalités), Université Paris-Sud, CNRS, UMR8081, Orsay, France

Total Liquid Ventilation (TLV) has been investigated as a medium for gas transport and diffusion. It has been used with perfluocarbons (PFCs), with perfluorooctane (PFOC) in particular, which showed good tolerance in vivo. To follow PFOC administration and clearance in rat lungs, we used dual-nuclei MRI and MRS with a home-build double-resonant coil. PFOC kinetics and clearance times are presented in this work.

Damien Pike^1,2, Dante Capaldi^1,2, Sarah Ashley Mattonen², Fumin Guo^1,3, Aaron Ward², David McCormack⁴, and Grace Parraga^1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, ²Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, ³Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada, ⁴Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada

Current methods for evaluating pulmonary ventilation heterogeneity from MRI are focused on quantifying ventilation defects although this measurement does not reflect ventilation patchiness or regional heterogeneity on smaller-volume or length scales. Hence, our objective was to develop a second-order texture analysis algorithm to quantify and characterize ³He ventilation heterogeneity in healthy never-smokers and participants with respiratory disease. Preliminary results in a training dataset showed that ³He MRI texture measurements correlated with spirometry (FEV1/FVC), ³He VDP and Vencov in healthy never-smokers.

Hal Cecil Charles¹, Randall W. Jones², Ahmed F. Halaweish³, and Maureen D. Ainslie^1
1Radiology, Duke Image Analysis Laboratory, Duke University Medical School, Durham, NC, United States, ²ScanMed, Omaha, Nebraska, United States,³Currently at Siemens Healthcare, MN, United States

Airway diseases (e.g. COPD and asthma) represent an economic burden in the US of approximately $100 billion annually and up to $90 billion annually, respectively. In order to fully understand lung function in airway disease a major challenge lies in the regional determination of poorly ventilated compartments in the lung. We have developed a method of imaging gas wash-in and wash-out that gives us a quantitative measure of mechanical ventilation — the rate of gas replacement normalized to gas volume. We have implemented parallel imaging of perfluorinated gas/oxygen mixtures to shorten breath hold times in subjects with severe lung disease.

Neil James Stewart¹, Juan Parra-Robles¹, and Jim Michael Wild^1
1Academic Unit of Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

Finite-element simulations of xenon diffusive exchange NMR in the lungs were performed using: realistic 2D geometries derived from human lung histology; and 3D uniform cylindrical capillary models. Simulated ¹²⁹Xe MR signal dynamics from the cylinder models agreed well with previous ¹²⁹Xe chemical shift saturation recovery (CSSR) MR data. The non-uniform distribution of tissue thicknesses in the histology sections considerably altered the shape of the predicted ¹²⁹Xe signal dynamics. Artificial thickening of alveolar septa caused increased diffusion-limitation of gas-exchange as expected from MR measurements. These findings have implications for future design of ¹²⁹Xe MR experiments and modelling of lung microstructure.

Dante Capaldi^1,2, Khadija Sheikh^1,2, Sarah Svenningsen^1,2, Damien Pike^1,2, David G McCormack³, and Grace Parraga^1,2
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

Hyperpolarized noble gas MRI provides a way to visualize and regionally measure ventilation heterogeneity using the ventilation defect percent (VDP), although this normalized volume does not reflect spatial differences in subjects with the same VDP. We hypothesized that regional differences in ventilation heterogeneity are physiologically relevant, and hence the objective of this algorithm development project was to develop a way to spatially quantify ventilation heterogeneity obvious in thoracic 3He MRI. Preliminary results in COPD and bronchiectasis subjects with the same VDP showed spatially different ventilation heterogeneity similar to LCI measurements in the same subjects.

Yi Xin¹, Hooman Hamedani¹, Maurizio Cereda², Sarmad Siddiqui¹, Mehrdad Pourfathi¹, Harrilla Profka¹, Stephen Kadlecek¹, Justin Clapp¹, Masaru Ishii^1,3, and Rahim R. Rizi^1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, ²Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA, United States, ³Otolaryngology, Johns Hopkins University, MD, United States

Spatial airspace dimensions can be evaluated via hyperpolarized Xenon diffusion MRI. ADC is increased in the atelectitic lung due to the alveolar overdistension, which can be mitigated by the proper recruitment strategy.

Yulin V Chang¹, James D Quirk¹, Mario Castro², and Dmitriy A Yablonskiy^1
1Radiology, Washington University in St. Louis, St. Louis, MO, United States, ²Medicine, Washington University in St. Louis, St. Louis, MO, United States

Although diffusion-based in vivo lung morphometry with hyperpolarized gases MRI is a powerful tool to study lung diseases, it is usually performed in a 2D mode with only a few slices because of the requirement for repetitive imaging of each slice at different diffusion gradients. Here we present a 3D imaging method that employs multi-channel receive coils and parallel imaging reconstruction techniques. This accelerated imaging scheme allows whole-lung coverage for in vivo lung morphometry measurement with improved resolution and minimum loss of accuracy in a single breath-hold.

Sarah Svenningsen^1,2, Bastiaan Driehuys³, David G McCormack⁴, and Grace Parraga^1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, ²Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, ³Department of Radiology, Duke University, Durham, North Carolina, United States, ⁴Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada

To accelerate clinical translation and regulatory approval of inhaled gas MRI of respiratory disease, the etiology of ventilation defects must be determined and validation with clinically-acceptable measurements, such as FEV₁ must be undertaken. We compared the performance of ³He MRI ventilation and FEV₁to discriminate asthmatics and healthy volunteers. ³He MRI VDP and VenCOV provided diagnostic accuracy that was similar to FEV₁. Estimated likelihood ratios suggested that the most accurate diagnosis of asthma was generated using ³He MRI VDP. Next steps include testing more sensitive ¹²⁹Xe MRI ventilation defects in the same validation model.

Haidong Li¹, Zhiying Zhang¹, Xiuchao Zhao¹, Xianping Sun¹, Chaohui Ye¹, and Xin Zhou^1
1National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, Hubei, China

We proposed a new method to evaluate the lung function by measuring the time constant of oxygen consumption (T_O-C) in the lung with hyperpolarized xenon MR. It demonstrated that such time constant has a significant difference between COPD and healthy rats, and we believe this parameter is helpful to quantify the oxygen concentration in oxygen therapy of patients.

Iga Muradyan¹, Samuel Patz¹, Mikayel Dabaghyan², Mirko Hrovat², and James P. Butler^1
1Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States, ²Mirtech, Inc., Brockton, MA, United States

Obtaining regional alveolar p_AO₂ is a coveted goal in pulmonary medicine, as it reflects both ventilation and perfusion. Hyperpolarized gases, mostly ³He were used to map p_AO₂. For ³He this is straightforward as helium is virtually insoluble in tissue. Xe, however, dissolves into tissue and blood and is carried away from the alveolar space, thus contributes to the loss of the ¹²⁹Xe MRI signal. To date no attempt has been made to address this issue. Here we report a novel use of SB-XTC to measure p_AO₂ while simultaneously measuring and taking into account xenon gas exchange on the signal decay.

Maxim Terekhov¹, Ursula Wolf², Klaus K Gast², Christian Hoffmann², Sergei Karpuk³, Christian Mrozek³, Christoph Dueber², and Laura Maria Schreiber^1
1Radiology Department, Section of Medical Physics, Johannes Gutenberg University Medical Center Mainz, Mainz, Germany, ²Radiology Department, Johannes Gutenberg University Medical Center Mainz, Mainz, Germany, ³Institute of Physics, Johannes Gutenberg University, Mainz, Germany

In the present paper the intermediate results of open clinical study on HP-3He-MRI measurements performed in bronchial asthma patients are presented. The particular aim was to investigate the effect of bronchodilatation on the alveolar pO2 measured with 3He-MRI, and to correlate the variation with the pulmonary function tests (PFT). For the 50% of patient data analyzed up to now we confirmed tentatively the increase of aPO2 after BDL on about 5%. The median value of oxygen consumption rate appears to be unchanged after BDL. However, the heterogeneity of variation over the patients increases by at least 50%.

Body DWI, Technical Development & Contrast

Wednesday, 3 June 2015

Haibo Zhang¹, Huadan Xue¹, Hui Liu², Stemmer Alto³, Kannengiesser Stephan³, Kiefer Berthold⁴, and Zhengyu Jin^1
1Radiology, Peking Union Medical College Hospital, Beijing, Beijing, China, ²NEA MR Collaboration, Siemens Ltd., China, Shanghai, China, ³Healthcare, Siemens AG, Erlangen, Germany, ⁴Radiology, Siemens, Erlangen, China

There are various techniques to address the susceptibility artifact in DWI. However, the current available DWI techniques are still quite challenge for whole body DWI applications. In this report, we investigated a prototype slie by slice shimming WBDWI sequence for lymphma and MM patients. In the most difficult region such as neck, we achieved a higher rate of good image quality and consistent measures in other body regions as comapred to conventional WBDWI.

Pelin Aksit Ciris^1,2, Jr-yuan George Chiou^1,2, Andriy Fedorov^1,2, Clare M. Tempany-Afdhal^1,2, Bruno Madore^1,2, and Stephan E. Maier^1,2
1Brigham and Women's Hospital, Boston, MA, United States, ²Harvard Medical School, Boston, MA, United States

Results are shown whereby good-quality prostate DWI results were obtained in a relatively-short period of time (5 min), with improved geometric fidelity over single-shot EPI imaging. The approach involved an accelerated multi-shot diffusion imaging method previously developed for brain imaging and adapted here for the prostate. Measurements of prostate size indicated an improvement in geometric fidelity by about 2.5-fold.

Hua Li¹, Feng Wang¹, Xiaoyu Jiang¹, Junzhong Xu¹, and John C. Gore^1
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States

Diffusion MRI imaging has previously been used to evaluate both structural and functional changes in various renal diseases. However, conventional pulsed gradient spin echo (PGSE) methods are highly sensitive to motion and flow artifacts. By contrast, oscillating gradient spin echo (OGSE) diffusion methods are less affected by bulk motion and the IVIM effect. In addition, OGSE methods may provide new insights into kidney microstructure at shorter length scales compared with PGSE. The goal of this study was to assess the feasibility of reliable in vivo diffusion measurements in kidneys with OGSE sequences.

Piotr Obara¹, Valentina Taviani¹, Andreas Loening¹, Andrei Iagaru¹, Brian Hargreaves², and Shreyas Vasanawala^2
1Radiology, Stanford Hospital, Stanford, California, United States, ²Stanford Hospital, Stanford, California, United States

As the plane of acquisition in MRI can alter image quality and lesion detectability, we evaluated the preferred acquisition plane for diffusion-weighted imaging (DWI) acquired as a component of whole body PET-MR examinations. Two readers evaluated DWI images from PET-MR data sets acquired in coronal (cDWI) and axial (aDWI) planes. Ability to identify lesions was compared to PET-CT; both cDWI and aDWI demonstrated good sensitivity, however, specificity on a by-patient basis was low due to false positive findings in osseous structures and lymph nodes. Readers demonstrated less uncertainty regarding findings and rated image quality higher on cDWI images.

Jian He¹ and Bin Zhu^1
1Department of Radiology, Nanjing Drum Tower Hospital, Nanjing, Jiangsu, China

Sixteen patients with cervical cancers underwent intravoxel incoherent motion (IVIM) imaging with 13 b values (0~1,000 s/mm2) on a 3 T MR scanner before, 2 and 4 weeks after start of concurrent chemoradiotherapy (CCRT). D and ADC values of bone marrows within the radiation field (RF) increased significantly at 2 weeks and then returned to baseline levels at 4 weeks. f values of bone marrows within the RF increased significantly at 2 weeks and continued to increase at 4 weeks. Parameters of bone marrow outside the RF and gluteus remained unchanged.

Oi Lei Wong^1,2, Gladys Goh Lo³, Jing Yuan⁴, Wai Kit Chung³, Max W. K. Law⁴, Benny W. H. Ho³, and Michael D. Noseworthy^2,5
1Department of Medical Physics and Applied Radiation Science, McMaster University, Hamilton, Ontario, Canada, ²Imaging Research Center, St.Joseph's Healthcare, Hamilton, Ontario, Canada, ³Department of Diagnostic & Interventional Radiology, Hong Kong Sanatorium & Hospital, Hong Kong, China,⁴Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China, ⁵Department of Electrical and Computer Engineering, McMaster Univeristy, Hamilton, Ontario, Canada

Pseudo-hepatic anisotropy artifact has been related to elevation in liver ADC and DT metrics. In this study, we assumed pseudo-hepatic artifact mainly affect perfusion related IVIM metrics. As a result, three type of liver tissue (liver parenchyma, motion contaminated liver parenchyma and vessel) can be identified due to the presence of pseudo-hepatic anisotropy artifact. Based on our result, we have revealed that the effect of pseudo-anitotropy artifact can be minimized using multiple gradient encoding directions.

Takeshi Yoshikawa¹, Yoshiharu Ohno¹, Katsusuke Kyotani², Saori Sato³, Yoshimori Kassai³, Hisanobu Koyama⁴, Keitaro Sofue⁴, and Kazuro Sugimura^4
1Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, ²Center for Radiology and Radiation Oncology, Kobe University Hospital, Kobe, Hyogo, Japan, ³Toshiba Medical Systems Corporation, Otawara, Tochigi, Japan, ⁴Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan

The assessment and classification of anatomy of hepatic artery is an essential step for both diagnosis and management of various diseases in the upper abdomen. Development of non- invasive imaging techniques for this purpose is an urgent problem. Our results suggested that hepatic artery can be assessed and classified by non-contrast MRA and is comparable to CTA in majority of patients.

Akihiro Furuta¹, Hiroyoshi Isoda¹, Tsuyoshi Ohno¹, Rikiya Yamashita¹, Shigeki Arizono¹, Aki Kido¹, Koji Fujimoto¹, Naotaka Sakashita², and Kaori Togashi^1
1Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan, ²Toshiba Medical Systems Corporation, Otawara, Tochigi, Japan

The LGV with information of flow direction was able to be visualized on MRI using bSSFP sequence with T-SLIPs.

Harri Merisaari¹, Jussi Toivonen², Marko Pesola³, Pekka Taimen⁴, Peter J Boström⁵, Tapio Pahikkala², Hannu J Aronen³, and Ivan Jambor^3
1Turku PET Centre, University of Turku, Turku, Finland, ²Department of Information Technology, University of Turku, Turku, Finland, ³Department of Diagnostic Radiology, University of Turku, Turku, Finland, ⁴Department of Pathology, Turku University Hospital, Turku, Finland, ⁵Department of Urology, Turku University Hospital, Turku, Finland

We elevated the effect of 4083 different b-value combinations on the prostate cancer detection, Gleason score prediction, and repeatability of monoexponential model for diffusion weighted imaging (DWI) using b-values up to 2000 s/mm². Fifty patients with histologically confirmed PCa underwent two repeated 3T MRI examinations before radical prostatectomy. DWI was performed using 12 equally distributed b-values. B-value distributions containing only b values in end of the b-value range (~1500 to 2000 s/mm²) demonstrated the lowest diagnostic performance and repeatability while the rest of b values distributions had similar performance and repeatability.

Caiyuan Zhang¹, Yanfen Cui¹, Yong Zhang², and Dengbin Wang^1
1Department of Radiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai, China, ²MR Research, GE healthcare, Shanghai, Shanghai, China

Intravoxel incoherent motion (IVIM) MR imaging derived parameters, as a non-invasive method could separate the effect of water molecular diffusion and microcirculation perfusion and therefore has potential to evaluate the staging of liver fibrosis. Currently, studies of IVIM in patient or animal model with liver fibrosis yielded contradictory results. Therefore, we performed IVIM MR imaging for well-controlled carbon tetrachloride induced liver fibrosis model in rats to evaluate its capability for prediction of severity of liver fibrosis. Based on histopathological findings, we analyzed the relationship between normal rats and rats with different staging of liver fibrosis, and relationship among individual fibrosis staging. Our studies indicated that D and D* showed better diagnostic performance than ADC for predicting the presence of liver fibrosis, particularly, D* has potential to differentiate moderate and advanced fibrosis from hepatic fibrosis. It is promising that parameters derived from IVIM were stable and has potential to be clinical use in monitoring fibrosis progression and evaluation of anti-fibrosis treatment response.

Hersh Chandarana^1,2, Annie Wang¹, Akio Yoshimoto¹, Alampady Shanbhogue¹, Mary Bruno¹, Tiejun Zhao³, Esther Raithel⁴, and Ricardo Otazo^1,2
1Radiology, Center for Biomedical Imaging, NYU School of Medicine, New York, NY, United States, ²Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), NYU School of Medicine, New York, NY, United States, ³Siemens Medical Solutions, New York, NY, United States, ⁴Siemens AG, Healthcare, Erlangen, Germany

This work proposes a novel approach for performing breath-held 3D isotropic magnetic resonance cholangiopancreatography (MRCP) imaging by using a joint compressed sensing and parallel imaging approach (SPARSE-SENSE) that exploits the inherent sparsity in the MRCP dataset to reconstruct highly undersampled data. Using a prototype 3D-SPACE sequence, only 5% of k-space was sampled in a 20-second breath-hold using a 2D variable-density random undersampling pattern, and reconstructed with an iterative algorithm that enforces joint sparsity among all coils (BH-SPARSE-SPACE). BH-SPARSE-SPACE was approximately 15 times faster than respiratory-triggered 3D T2-weighted acquisition (acquisition time of approximately 5 min) without loss in image quality.

Andrew J Patterson¹, Andrew N Priest¹, David J Bowden¹, Martin J Graves¹, and David J Lomas^1
1Department of Radiology, Addenbrooke's Hospital & University of Cambridge, Cambridge, England, United Kingdom

A number of studies have investigated Blood Oxygen Level Dependent (BOLD) contrast changes in measuring perturbations in oxygenation within neoplasms. The purpose of this study is to investigate the utility of oxygen to induce temporal changes in T2* in hepatocellular carcinoma (HCC) patients (n=10) with a background of diffuse liver disease. An elevated BOLD signal was noted in HCC and in diffuse liver disease. These findings were not observed in a healthy volunteer cohort (n=11). These study results suggest fibrosis as well as neoplasmic changes can result in measurable BOLD signal intensity response to hyperoxic stimuli.

El-Sayed H. Ibrahim^1,2, Robert Pooley², Joseph Cernigliaro², Mellena Bridges², Jamie Giesbrandt², James Williams³, and William Haley^2
1University of Michigan, Ann Arbor, MI, United States, ²Mayo Clinic, Jacksonville, FL, United States, ³Indiana Unicersity, IN, United States

With the development of ultra-short echo-time (UTE) MRI sequences, adequate imaging of kidney stones becomes possible. Although few studies investigated imaging stones in certain experimental settings (in gel phantoms using volumetric coils), no study so far investigated the results of imaging stones with natural surroundings (inside kidneys) and using the body surface coil, which is the purpose of this work. The results show that MRI has the potential for imaging stones of different types and sizes. If successful for in-vivo imaging, the developed technique could be a valuable alternative to CT for imaging patients with higher sensitivity to radiation exposure.

Brian J. Soher¹, Ahmed F. Halaweish², and H. Cecil Charles^1
1Duke University Medical Center, Durham, NC, United States, ²Siemens Healthcare, MN, United States

MRI of pulmonary ventilation using perfluoropropane as a gas contrast agent enables a dynamic, multi-breath assessment of the spatiotemporal distribution of the gas within the airspaces. The dynamic nature of the acquisitions gives way to the generation of various intensity and parametric based biomarkers of pulmonary ventilation encompassing ventilation distribution, efficiency and the severity, size and persistence of gas trapping and ventilation defects. In this work we demonstration the extraction of the biomarkers relating to the aforementioned physiological phenomenon.

Yi-Chun Wang^1,2, Wen-Pei Wu^2,3, Cheng-In Hoi², Chen-Te Chou^2,3, and Ran-Chou Chen^2,4
1Radiology, taoyuan general hospital ministry of health and welfare, Taiwan, Taoyuan, Taiwan, ²Biomedical Imaging and Radiological Science, National Yang-Ming Medical University, Taipei, Taiwan, ³Radiology, Chang-Hua Christian Hospital, Taiwan, ⁴Radiology, Taipei city Hospital, Taiwan, Taipei, Taiwan

According to AASLD, a diagnosis of HCC can be made by that a nodule larger than 1.0 cm showed typical enhancement on dynamic CT or MR. However, up to 44% HCCs show atypical features on dynamic contrast-enhanced images. The purpose of this study was to evaluate whether Gd-EOB-DTPA enhanced hepatocyte phase MR images can improve the diagnosis of HCC in patients with atypical enhanced cirrhotic nodules detected on conventional dynamic MR images. In our study, hypointense on hepatocyte phase having 83.5% diagnostic accuracy is superior to the dynamic phases. If we combine the hypointensity on hepatocyte phase with arterial hypervascularity, the specificity will be 95.7%. However, when we combined the hypointensity on hepatocyte phase with arterial isovascularity, the specificity is only 73.9%.

Jutta Janke¹, Gunnar Schley², Michael Uder¹, Kai-Uwe Eckardt², Carsten Willam², and Tobias Bäuerle^1
1Institute of Radiology, University Hospital Erlangen, Erlangen, Germany, ²Nephrology and Hypertensiology, University Hospital Erlangen, Erlangen, Germany

Diffusion tensor imaging (DTI) is an emerging technique for acquisition of renal pathologies. Combining DTI parameters apparent diffusion coefficient (ADC) and fractional anisotropy (FA) with mapping of relaxation times (T1, T2, T2*) as well as volumetry of murine kidneys at 7T ex vivo, we could differentiate significantly between acute kidney failure and chronic interstitial nephritis as compared to untreated controls, respectively. Interestingly, tract alterations were diagnosed and visualized between control and pathologic kidneys as determined by DTI tractography. In conclusion, DTI and multiparametric mapping at 7T enables characterization and diagnosis of acute and chronic kidney changes in experimental models.

Qun Zhao^1,2, Houchun H Hu³, Qingying Meng¹, Forrest Goodfellow^2,4, and Steve Stice^2,4
1Bioimaging Research Center, University of Georgia, Athens, GA., United States, ²Regenerative Bioscience Center, University of Georgia, Athens, GA., United States, ³Dept. of Radiology, Phoenix Children's Hospital, Phoenix, AZ, United States, ⁴Department of Animal & Dairy Science, University of Georgia, GA., United States

In this study, Water Fat Imaging (WFI) was conducted on chick embryos in ovo on a 7T MR scanner to examine body fat composition in the embryos.

Lindsey Alexandra Crowe¹, Iris Friedli¹, Christian Vesin², Lena Berchtold³, Pierre-Yves Martin⁴, Sophie de Seigneux⁴, and Jean-Paul Vallée^1
1Division of Radiology / Faculty of Medicine, Geneva University Hospital, Geneva, Switzerland, ²Division of Cell Physiology and Metabolism, Geneva University Hospital, Geneva, Switzerland, ³Division of General Internal Medicine, Geneva University Hospital, Geneva, Switzerland, ⁴Division of Nephrology, Geneva University Hospital, Geneva, Switzerland

We present readout-segmented diffusion at 3T (clinical scanner) in rat with reduced EPI distortions. A non-invasive technique to assess renal fibrosis and inflammation is proposed and validated in different rat model pathologies. In UUO (severe) and BSA (moderate), ADC from segmented RESOLVE correlated with fibrosis (p<0.001). For BSA with less fibrosis ADC difference from control was significant (p=0.007) emphasizing sensitivity (fibrosis <20%). There was correlation with inflammation for UUO. Our results demonstrated the power of RESOLVE. The proposed protocol may be easily translated to the clinical practice to improve CKD patient treatment and decrease significantly the need for renal biopsy.

Haoran Sun¹, Huanhuan Wu², and Ziheng Zhang^3
1Radiology, Tianjin Medical University Hospital, Tianjin, Tianjin, China, ²Tianjin Medical University Hospital, China, ³MR Research China,GE Healthcare, Shanghai, China

Intravoxel incoherent motion (IVIM) DWI has recently shown potential to assess functional changes of chronic kidney diseases. This study is to evaluate the feasibility of the mono- and bi-exponential models measurements through multi-b DW-MRI in reflection of the serial variation of diffusion and microperfusion noninvasively on adriamycin induced rodent renal injury models. It was found the serial variation of ADC, f, D* values are sensitive to the progression of renal disorder induced by adriamycin and according to the histological findings, which suggests one, we can noninvasively assess renal injury according using DW-MRI method.

Annelise M Silva^1,2, Anshuman Panda³, Raul Pannala⁴, Vijay P Singh⁴, Krutika Patel⁴, Vishnu T Kommineni⁴, Teresa Wu⁵, Yinlin Fu⁵, and Alvin C Silva^3
1Research, Mayo Clinic, Phoenix, Arizona, United States, ²Arizona State University, Tempe, Arizona, United States, ³Radiology, Mayo Clinic, Phoenix, Arizona, United States, ⁴Gastroenterology, Mayo Clinic, Phoenix, Arizona, United States, ⁵School of Computing, Informatics, and Decision Systems Engineering, Arizona State University, Tempe, Arizona, United States

There is increasing evidence that excess intrapancreatic fat (IPF) has deleterious effects and plays a role in various disease states including diabetes, pancreatitis, and the metabolic syndrome. Moreover, it may also predispose to pancreatic cancer in association with increased dietary fat intake. At present, IPF assessment is subjective, without a standardized tool for accurate noninvasive evaluation. Our goal is to develop and validate a comprehensive MR imaging protocol for noninvasive fat quantification of the entire pancreas. Specifically, MR Spectroscopy and Multi-Echo Dixon techniques will be optimized and validated for their efficacy in providing accurate intra-pancreatic fat (IPF) quantification.

Kevin J Sinclair¹, Lanette J Friesen-Waldner¹, Colin M McCurdy¹, Curtis N Wiens², Trevor P Wade^1,3, Barbra de Vrijer⁴, Timothy RH Regnault^4,5, and Charles A McKenzie^1,3
1Medical Biophysics, University of Western Ontario, London, Ontario, Canada, ²Radiology, University of Wisconsin, Madison, Wisconsin, United States,³Robarts Research Institute, University of Western Ontario, London, Ontario, Canada, ⁴Obstetrics and Gynaecology, University of Western Ontario, London, Ontario, Canada, ⁵Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada

Growth restricted fetuses have been identified as being at increased risk of later life metabolic and cardiovascular disease. The purpose of this study was to identify developmental abnormalities in growth restricted guinea pig fetuses compared to healthy normals using MRI. Two maternal groups were scanned: one in which branches of the uterine artery were ablated to promote growth restriction of the fetuses, and a sham surgical group. Segmentation of anatomical and water-fat images of pregnant guinea pigs (N = 10) demonstrated asymmetrical growth restriction as well as a decrease in adipose tissue in growth restricted fetuses compared to normal.

Dong-Cheol Woo¹, Do-Wan Lee¹, Nayoung Kim¹, Chul-Woong Woo¹, Sang-Tae Kim¹, Jeong-Kon Kim¹, Kyungwon Kim¹, Youyol Song¹, Hyun-Kwon Ha¹, and Jin Seong Lee^1
1Asan Institute for Life Sciences, Asan Medical Center, Seoul, Seoul, Korea

The first goal of this study was to quantitatively assess regional changes in function and pathophysiological characteristics in renal IR injured mice and compare data obtained at baseline and following injury. The second goal was to correlate BOLD and DTI data using time-dependent scans. Our current findings suggest that MRI could be used to obtain pathophysiological data from separate renal compartments in IR-injured mice. Hence, BOLD and DTI may also provide functional and pathophysiological data on the allograft status following kidney transplant without the need to use a contrast agent.

Hing-Chiu Chang¹, Arnaud Guidon², Dan Xu³, Lloyd Estkowski⁴, Ersin Bayram⁵, Mei-Lan Chu^1,6, Mustafa R Bashir¹, Allen W Song¹, and Nan-kuei Chen^1
1Duke University Medical Center, Durham, North Carolina, United States, ²Global MR Applications and Workflow, GE Healthcare, Boston, MA, United States,³Global MR Applications and Workflow, GE Healthcare, Waukesha, WI, United States, ⁴Global MR Applications and Workflow, GE Healthcare, Menlo Park, CA, United States, ⁵Global MR Applications and Workflow, GE Healthcare, Houston, TX, United States, ⁶National Taiwan University, Taipei, Taiwan, Taiwan

Recent advancements in multi-shot EPI make it possible to acquire high-resolution DWI data. Although these methods have been successfully demonstrated in brain studies, multi-shot and high-resolution DWI of abdominal organs (e.g., liver) still cannot be reliably achieved because of enhanced motion. Here we first demonstrate that, by integrating navigator-based respiration-gated multi-shot DWI acquisition and multiplexed sensitivity encoded reconstruction, abdominal DWI of high-quality and high-resolution can be successfully achieved. The developed protocols should prove highly valuable for clinical examinations that require high-resolution DWI to detect subtle pathology, such as hydatid cysts, metastases and other types of lesions of the liver.

Chika C Obele¹, Christopher Glielmi², Justin Ream¹, Ankur Doshi¹, Naomi Campbell^1,3, Cheung Hoi Zhang¹, James Babb¹, Himanshu Bhat⁴, and Hersh Chandarana^1
1Radiology, NYU Scool of Medicine and NYU Langone Medical Center, New York, NY, United States, ²Siemens HealthCare, New York, NY, United States,³Radiology, Memorial Sloan Ketteringý, NY, United States, ⁴Siemens Healthcare, Charlestown, MA, United States

Techniques that can accelerate free-breathing diffusion weighted imaging (DWI) of the liver are of interest to decrease acquisition time while maintaining image quality. One promising method is multiband excitation approach that can acquire multiple slices simultaneously, thus decreasing repetition time (TR). In current study multiband DWI with 2 fold acceleration (mb2-DWI) was shown to decrease acquisition time by 40 to 50% compared to conventional DWI (c-DWI) for liver imaging. Despite shorter acquisition time, mb2-DWI had higher scores for overall image quality compared to c-DWI with identical lesion detectability. Thus, mb2-DWI can potentially replace the conventional DWI sequence in the liver.

Renal, Adrenal & Male Pelvis

Wednesday, 3 June 2015

Feng Wang^1,2, David Kopylov³, Zhongliang Zu^1,2, Keiko Takahashi^4,5, John C. Gore^1,2, Raymond C. Harris^4,5, Takamune Takahashi^4,5, and C. Chad Quarles^1,2
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, ²Institute of Imaging Sciences, Vanderbilt University, TN, United States, ³Drexel University, PA, United States, ⁴Vanderbilt O'Brien Mouse Kidney Physiology and Disease Center, Vanderbilt University, TN, United States,⁵Division of Nephrology and Hypertension, Vanderbilt University, TN, United States

Mouse models of diabetes (e.g. regular db/m, moderate type II diabetic db/db and advanced diabetic db/db eNOS-/-) provide especially valuable opportunities for evaluating the role of quantitative MRI as biomarkers of renal nephropathy. Diabetic nephropathy is associated with the changes in tissue metabolites (e.g. glucose, glycogen, glycosaminoglycan) that exhibit significant chemical exchange saturation transfer (CEST) effects in MRI. Here we applied CEST imaging at 7T to differentiate moderate and advanced diabetic kidney disease. The sensitivity of glucoCEST in assessing the progress of diabetic kidney disease was evaluated.

Chan Hong Moon¹, Alessandro Furlan², Jung-Hwan Kim², Tiejun Zhao³, Ron Shapiro⁴, and Kyongtae Ty Bae^2
1University of Pittsburgh, Pittsburgh, PA, United States, ²University of Pittsburgh, PA, United States, ³Siemens Medical Solutions, PA, United States, ⁴Thomas E. Starzl Transplantation Institute, PA, United States

We developed and evaluated the dual-tuned proton/sodium MRI technique of the kidney. The new technique was applied to sodium quantification to access the renal function in transplanted kidney. The renal sodium concentration and cortico-medullary sodium concentration of transplanted kidneys were lower than those of the healthy native kidneys.

Yanjun Li¹, Yuan Xie¹, Yong Zhang², Dandan Zheng³, and Guangming Lu^1
1Medical Imaging, Jingling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu, China, ²GE healthcare China, Shanghai, China, ³GE healthcare China, Beijing, China

The feasibility of DKI in the human kidneys has been demonstrated recently. We performed DKI using 3 b values with 15 directions in 11 renal allografts recipients. Our results showed FA was significantly greater in medulla than in cortex, while cortical Ka showed significant greater values than medullary Ka. Cortical MK, Ka, Kr and medullary Ka correlated with eGFR negatively and significantly. In conclusion, it is possible that DK imaging may serve as an effective model for functional evaluation of transplanted kidneys.

Jeff L Zhang¹, Christopher C Conlin¹, Kristi Carlston¹, Daniel Kim¹, Glen Morrell¹, Kathryn Morton¹, and Vivian S Lee^1
1Radiology, University of Utah, Salt Lake City, Utah, United States

Conventional measures of renal function, such as serum Cr, are insensitive to renal disease, particularly when only a single kidney is affected. Many have advocated low-dose MR renography, to measure renal function noninvasively. In this study we systematically analyzed how the accuracy of tracer kinetic models to analyze MR renography data depends on injected Gd dose and on image acquisition parameters, such as TI in SR sequence. Following a Monte Carlo simulation, we compared renal function estimates using different protocols in 22 patients.

Yasuhisa Kurata¹, Aki Kido¹, Koji Fujimoto¹, Kayo Kiguchi¹, Kyoko Takakura¹, and Kaori Togashi^1
1Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan

We aimed to evaluate the optimal BBTI for obtaining non-contrast-enhanced MRA of renal artery using time-SLIP technique at 3.0-T considering with the changes of renal blood velocities according to the ages. Quantitatively, relative signal intensity of renal artery was best at BBTI of 1400msec, and optimal BBTI for younger subjects (under 50y.o.) was 1600msec and 1800msec, and that for older subjects was 1800msec qualitatively. Then, suggestive BBTI may be 1600-1800msec regardless of the renal blood velocity at 3T.

Christopher C. Conlin¹, Jeff L. Zhang¹, Glen Morrell^1,2, Kristi Carlston¹, Tom Greene³, Kathryn A. Morton², and Vivian S. Lee^1,2
1Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, Utah, United States, ²Department of Radiology, University of Utah School of Medicine, Salt Lake City, Utah, United States, ³Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, United States

Renal function is a critical factor in determining the priority of liver-transplant candidates and is typically determined from serum creatinine or cystatin C measurements. However, the formulas used to calculate GFR from these measurements may overestimate renal function in patients with low muscle-mass, such as those with cirrhosis, thereby lowering their transplant priority. In this study, we show that we can calibrate the GFR formulas to account for reduced muscle-mass in cirrhosis patients by measuring paraspinal fat-infiltration from MR images acquired as part of routine liver examination. This calibration leads to more accurate estimates of renal function.

Sarah Keller¹, Bjoern Schoennagel¹, Zhiyue Jerry Wang², Regine Grosse³, Peter Nielsen⁴, Gerhard Adam¹, Roland Fischer¹, and Jin Yamamura^1
1Diagnostic and Interventional Radiology, University Medicine Hamburg Eppendorf, Hamburg, Germany, ²Radiology, Children's Medical Center Dallas, Dallas, Texas, United States, ³Pediatric Hematology and Oncology, University Medicine Hamburg Eppendorf, Hamburg, Germany, ⁴Institute of Biochemistry and Molecular Biology, Center of Experimental Medicine, Hamburg, Germany

Renal iron accumulation leading to renal dysfunction and impairment may be an underestimated factor during disease course of transfusion dependent haematological diseases like Hereditary Hemochromatosis (HHC), Sickle Cell Disease (SCD) and Transfusion dependent Thalasemia (TDT). R2* -MRI and biomagnetic liver susceptometry (SQUID-BLS) was applied to estimate cortical and medullary renal and liver iron content. Correlation analysis of iron accumulation and laboratory findings (lactate dehydrogenase, bilirubin) was performed to estimate organ involvement.

Joshua Kaggie¹, Vivian S Lee¹, Robb Merrill¹, and Glen Morrell^1
1Utah Center for Advanced Imaging Research, Radiology, University of Utah, Salt Lake City, UT, United States

An apparatus was developed that enabled invasive acquisition of renal pO2 in vivo simultaneously with renal BOLD T2* measurements. We found excellent agreement between renal pO2 and T2* measurements across different renal physiologic states. Invasive renal oxygenation measurements of pO2 are useful for validating BOLD measurements and can help elucidate factors that may confound the estimation of oxygenation from T2* measurements.

Junjie Ren¹, Shengzhang Ji¹, Chunxia Li¹, Weidong Su¹, Chunqing Song¹, Lijun Qiu¹, Donghong Xu¹, Hao Wang¹, Queenie Chan², and Yu Zhang^3
1The 4th center hospital of TianJin, Tianjin, Tianjin, China, ²Philips Healthcare, Hongkong, China, ³Philips Healthcare, Beijing, China

This study aimed to evaluate the renal oxygenation in type 2 diabetes and discover the early changes of kidney by using BOLD-MRI.

Lu-Ping Li^1,2, Jing Lu^2,3, Tammy Franklin¹, Ying Zhou⁴, Richard Solomon⁵, and Pottumarthi V. Prasad^1,2
1Department of Radiology / Center for Advanced Imaging, Northshore University Healthsystem, Evanston, IL, United States, ²Pritzker School of Medicine, University of Chicago, Chicago, IL, United States, ³Department of Obstetrics and Gynecology, Northshore University Healthsystem, Evanston, IL, United States,⁴Center for Clinical & Research Informatics, Northshore University Healthsystem, Evanston, IL, United States, ⁵Nephrology, University of Vermont, VT, United States

The current clinical marker (serum creatinine) is not time-sensitive to guide intervention to prevent iodinated contrast induced acute kidney injury (CIAKI). Blood-oxygenation-level dependent (BOLD) MRI showed near real time changes in renal hypoxia following contrast administration in a previous functional CIAKI rat model. In this study, streptozotocin induced diabetic rat was used as a CIAKI susceptible model. While the renal hypoxia in medulla increased following contrast administration, it fell back towards baseline. Urinary NGAL increasing confirmed AKI. This indicates the need for real time marker to monitor the temporal changes of renal hypoxia during contrast administration.

Gavin Low^1,2, Nicola Eve Owen³, Ilse Joubert¹, Andrew J Patterson¹, Martin J Graves¹, Graeme J.M. Alexander³, and David J Lomas^1
1Radiology, Addenbrooke's Hospital, Cambridge, England, United Kingdom, ²University of Alberta, Edmonton, Alberta, Canada, ³Hepatology & Gastroenterology, Addenbrooke's Hospital, Cambridge, England, United Kingdom

The purpose of this study was to evaluate the influence of vibration frequency and imaging plane on stiffness measurements in renal magnetic resonance elastography (MRE). Coronal 90-Hz and 60-Hz, sagittal 90-Hz and axial 90-Hz MRE sequences of the kidneys were performed in 12 patients on a 1.5-T MRI. The MRE measured renal stiffness on different vibration frequencies (‘90-Hz’ versus ‘60-Hz’) and different imaging planes (‘coronal’ versus ‘sagittal oblique’ versus ‘axial’ projection) were compared to determine the influence of these variables. A significant difference in renal stiffness was found between frequencies (p = 0.003) and between imaging planes (p < 0.001).

Ying Gao¹, Yong Chen², Dan Ma¹, Yun Jiang¹, Katherine M. Dell³, Mitchell L. Drumm^3,4, Mark A. Griswold^1,2, Chris A. Flask^1,2, and Lan Lu^2,5
1Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States, ²Radiology, Case Western Reserve University, Cleveland, Ohio, United States, ³Pediatrics, Case Western Reserve University, Cleveland, Ohio, United States, ⁴Genetics, Case Western Reserve University, Cleveland, Ohio, United States, ⁵Urology, Case Western Reserve University, Cleveland, Ohio, United States

Conventional MRI methods are highly susceptible to motion artifacts, especially for preclinical body imaging applications. We have implemented an MRF-FISP acquisition on a high field preclinical MRI scanner to simultaneously obtain in vivo T₁, T₂, and proton density maps for both healthy and polycystic kidneys in mice and rats. Initial results show that our preclinical MRF technique can provide reasonable estimates of relaxation times and proton density and is sensitive to known pathology. Most importantly, these results confirm that the MRF technique is inherently resistant to respiratory motion artifacts which is a key advantage for body imaging applications.

Peter Gibbs¹, Martine Dujardin¹, and Lindsay Turnbull^1
1Centre for MR Investigations, University of Hull, Hull, East Yorkshire, United Kingdom

T2 weighted images of ovarian lesions have been assessed using texture analysis. Uneven group sizes, which can cause bias in statistical models leading to over-fitting of the majority class, were avoided by employing synthetic minority oversampling methods. Significant differences between groups were noted for 12/16 texture parameters and a multinomial logistic regression model utilised 4 parameters (f2, f14, f15, f16) in achieving a diagnostic accuracy of 71% for a training dataset and 61% for a test dataset.

zhengyang zhou¹, Haiping yu¹, Ying Hong², and Jing Fang^2
1Radiology, Affiliated Drum Tower Hospital,School of Medicine,Nanjing University,China, Nanjing, Jiangsu, China, ²Gynecology, Affiliated Drum Tower Hospital,School of Medicine,Nanjing University,China, Nanjing, Jiangsu, China

Thirty-eight cervical cancer patients underwent preoperatively MR lymphography with gadodiamide and intraoperative lymphatic mapping with isosulfan blue for detection of SLNs. 79 SLNs were preoperatively detected by MR lymphography, whereas 81 SLNs were intraoperatively identified by blue dye-guided surgical dissection, with the detection power of 97.5%. When the combination of characteristics of margin and long-to-short-axis diameter ratio of SLN were taken into consideration, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of MR lymphography for SLN characterization were 94.4%, 96.7%, 89.5%, 98.3%, and 96.2%, respectively. Preoperative MR lymphography offers accurate diagnosis of SLN metastases in cervical cancer.

Jintang Ye¹, Jing Liu¹, Juan Wei², Bilgin Keserci³, Jianhua Zhang⁴, Xuedong Yang¹, Rong Rong¹, Ying Zhu¹, Queenie Chan⁵, and Xiaoying Wang^1
1Department of Radiology, Peking University First Hospital, Beijing, Beijing, China, ²Philips Research China, Shanghai, China, ³MR Therapy Clinical Science, Philips Healthcare, Seoul, Korea, ⁴Philips (China) Investment Co., Ltd, Beijing, China, ⁵MR Clinical Science, Philips Healthcare, Hongkong, China

To report the first experience with T2*-weighted (T2*W) images in the assessment of non-perfused volume (NPV) inside uterine fibroids response to MR-guided high intensity focused ultrasound (HIFU), with comparison of contrast enhanced T1-weighted (CE-T1W) images.

Pelin Aksit Ciris^1,2, Robert V. Mulkern^2,3, Mukund Balasubramanian^2,3, Antonio L. Damato^2,4, Ravi T. Seethamraju⁵, Janice Fairhurst¹, Ferenc A. Jolesz^1,2, Clare M. Tempany-Afdhal^1,2, Ehud Schmidt^1,2, and Akila N. Viswanathan^2,4
1Brigham and Women's Hospital, Boston, MA, United States, ²Harvard Medical School, Boston, MA, United States, ³Boston Children's Hospital, Boston, MA, United States, ⁴Dana-Farber Cancer Institute, Boston, MA, United States, ⁵Siemens Healthcare, MA, United States

Tumor hypoxia increases treatment resistance and metastatic potential. MRI attempts to detect hypoxia in cervical cancer via R2* using multiple-gradient-echo (GRE) signals with a standard Mono-Exponential (ME) decay model were reported. We have evaluated this in gynecologic cancers post External-Beam-Radiation-Therapy (EBRT), and report that proper characterization of GRE signals requires a Gaussian Augmentation of the Mono-Exponential (GAME) decay model. GAME improves characterization significantly (p<0.05) in 25% of all tumor regions, and highly significantly (p<0.005) in 15% of all tumor regions, which improves the potential for finding biomarkers of e.g. oxygenation status, with potential to improve targeting of radiation treatment.

Mahnaz Nabil^1,2, Anahita Fathi Kazerooni^1,3, Hamidreza Haghighatkhah⁴, Sanam Assili¹, and Hamidreza Saligheh Rad^1,3
1Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran,²Department of Statistics, Tarbiat Modares University, Tehran, Iran, ³Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran, ⁴Department of Radiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Accurate characterization of benign and malignant ovarian cancers plays a critical role in decision making about the therapeutic strategy, for which DCE- MRI has been shown to be promising. Reliable prediction of malignancy in complex adnexal masses depends on proper selection of quantitative DCE-MRI descriptive parameters. In this work, we exploit an automatic classification method for selection of the best parameters in predicting the tumor malignancy, and propose a clinically applicable decision tree for accurate classification of benign and malignant complex ovarian cancers.

Xiang Zheng¹, Xisheng Cao¹, Youping Xiao¹, Yunbin Chen¹, and Weibo Chen^2
1Radiology Department, Fujian Provincial Cancer Hospital, Fuzhou, Fujian, China, ²Philips Healthcare, Shanghai, Shanghai, China

In order to evaluate the reproducibility of Diffusional Kurtosis Imaging (DKI) in uterine cervix in vivo, 20 healthy volunteers underwent duplicate MRI and DKI scans with an interval of 24 hours to 14 days. Metric K and D were obtained and measured. ICCs, CVs of both intra- and inter- observer showed the perfect stability of D and K in two scans. Therefore, DKI appears reproducible in providing useful information of non-Gaussian diffusion behavior in uterine cervix. And it is stable in the application in clinical researches.

Stephanie T. Chang¹, Andreas M. Loening¹, Marcus T. Alley¹, and Shreyas S. Vasanawala^1
1Dept. of Radiology, Stanford University, Stanford, CA, United States

We compared a conventional MR imaging protocol to a streamlined 10-minute protocol comprised of a single plane of T2 with fat saturation and a high-resolution, free-breathing, post-contrast 3D SPGR sequence in evaluating 19 patients with cervical or endometrial carcinoma. Two readers assessed imaging findings and assigned confidence scores. The high-resolution, post-contrast 3D SPGR sequence did not result in significantly different diagnoses or confidence scores compared to a conventional protocol, and can greatly reduce total scan time from 30-40 min to ~10 min.

Yanchun Wang¹ and Daoyu Hu^1
1Tongji Hospital Tongji Medical College, Wuhan, Hubei, China

Nowadays, Neoadjuvant chemotherapy (NACT) of cervical cancer is widely employed in clinical. The aim of NACT is to reducing the tumor size and eliminating latent/micro lymph node metastases or improving radiation sensitivity before surgery or radiotherapy. Unfortunately, the cancer progressed in some patients and the responded rate of NACT in cervical cancer only ranges from 65% to 87.5% . Non-responded NACT may increase the risk of tumor progression and surgical difficulty, and the response to NACT can be considered as an independent prognostic factor . When non-responded NACT occurs by RECISTs, modifying the treatment strategy has to be considered, including earlier surgery or radiation therapy . It does really need good early predictors to evaluate NACT respondents before RECISTs.

Yan Zhou¹, Jianyu Liu², Wei He², Yang Shen², Weidan Lu², Huici Zhu², Lizhi Xie³, and Zhenyu Zhou^3
1Peking University Third Hospital, Beijing, Beijing, China, ²Peking University Third Hospital, Beijing, China, ³GE Healthcare, Beijing, China

This study aimed at investigating the utility of intra-voxel incoherent motion model (IVIM) with multi-b values DWI in diagnosis and grading of cervical cancer. Moreover, the up to date concept of invasive edge of tumor was adopted, which had closer relation with tumor aggressiveness and prognosis. The results showed that both mono-exponential model and IVIM model could help to differentiate cervical cancer from normal cervix. Perfusion fraction (F) at tumor edge showed the best diagnostic performance in grading cervical squmous cancer. Therefore, IVIM model might demonstrate capability on differentiating and grading cervical cancer.

Jessica M Winfield¹, Nandita M deSouza^1,2, Andrew N Priest³, Jennifer C Wakefield², Charlotte Hodgkin³, Susan Freeman³, Matthew R Orton², and David J Collins^1,2
1MRI, Royal Marsden Hospital, Sutton, Surrey, United Kingdom, ²CRUK Cancer Imaging Centre, Institute of Cancer Research, Sutton, Surrey, United Kingdom,³Department of Radiology, Addenbrooke's Hospital, Cambridge, United Kingdom

Goodness-of-fit and repeatability of mono-exponential, stretched exponential and bi-exponential models of diffusion-weighted MRI data were assessed in 31 patients with primary and metastatic ovarian cancer scanned before and after chemotherapy. Coefficients of variation of repeated baseline measurements were used to assess repeatability of fitted parameters. Goodness-of-fit was assessed using the Akaike Information Criterion (AIC), which penalises additional parameters. Mono-exponential and stretched exponential models showed good repeatability (3 to 7 %) but the repeatability of the bi-exponential model was poor. After excluding the bi-exponential model, AIC analysis showed that the stretched exponential model was preferred in pre- and post-treatment data in all tumour sites.

Iris Friedli¹, Lindsey Alexandra Crowe¹, Lena Berchtold², Solange Moll³, Karine Hadaya⁴, Thomas De Perrot¹, Pierre-Yves Martin⁴, Sophie De Seigneux⁴, and Jean-Paul Vallée^1
1Division of Radiology, Faculty of Medicine, Geneva University Hospital, University of Geneva, Geneva, Switzerland, ²Division of Internal Medicine, Faculty of Medicine, Geneva University Hospital, University of Geneva, Geneva, Switzerland, ³Division of Pathology, Faculty of Medicine, Geneva University Hospital, University of Geneva, Geneva, Switzerland, ⁴Division of Nephrology, Faculty of Medicine, Geneva University Hospital, University of Geneva, Geneva, Switzerland

Whole kidney fibrosis and inflammation was non-invasively assessed with readout-segmented diffusion-weighted imaging in CKD patients. An internal validation study was performed using biopsy as a gold standard. A ΔADC, defined as the difference of mean ADC in the renal cortex and medulla improves fibrosis evaluation by comparison to ADC alone in renal transplant patients. Strong correlation was found comparing ΔADC (R2=0.70, p<0.001) to the fibrosis. A negative ΔADC was found in all patients with more than 40% of fibrosis suggesting the use of this index as predictor for renal fibrosis as confirmed by the results of the internal validation.

Yan Zhou¹, Jianyu Liu², Wei He², Yang Shen², Weidan Lu², Huici Zhu², Dandan Zheng³, and Ziheng Zhang^3
1Peking University Third Hospital, Beijing, Beijing, China, ²Peking University Third Hospital, Beijing, China, ³GE Healthcare, Beijing, China

This study aimed at investigating the utility of intra-voxel incoherent motion model (IVIM) with multi-b values DWI in diagnosis and grading of cervical cancer. Moreover, the up to date concept of invasive edge of tumor was adopted, which had closer relation with tumor aggressiveness and prognosis. The results showed that both mono-exponential model and IVIM model could help to differentiate cervical cancer from normal cervix. Perfusion fraction (F) at tumor edge showed the best diagnostic performance in grading cervical squmous cancer. Therefore, IVIM model might demonstrate capability on differentiating and grading cervical cancer.

Hepatobiliary I

Wednesday, 3 June 2015

Yu Shi¹, He An¹, Qiyong Guo¹, Richard L. Ehman², and Kevin J. Glaser^2
1Department of radiology, Shengjing hospital of china medical university, Shenyang, Liaoning, China, ²Department of Radiology, Mayo Clinic, Rochester, MN, United States

In this prospective study,ten healthy volunteers and 26 patients with pancreatic masses undertook MR Elastography on a 3T scanner to evaluate its usefulness for differentiating benign and malignant solid pancreatic lesions. The mean stiffness value of healthy pancreas was (1.12¡À0.11) kPa. Malignant lesion[(2.70¡À1.20) kPa] has much higher stiffness than both mass-forming pancreatitis[(1.59¡À0.31) kPa] and healthy pancreas.Mass-forming pancreatitis has slightly higher stiffness than healthy pancreas, but with apparent overlapping.Our study proved MR elastography might be a potential tool to different solid pancreatic masses.

Cheng-In Hoi¹, Wen-Pei Wu^1,2, Yi-Chun Wang^1,3, Chen-Te Chou^1,2, and Ran-Chou Chen^1,4
1Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan, Taiwan, ²Department of Radiology, Chang-Hua Christian Hospital, Taiwan, Taiwan, ³Department of Radiology, Taoyuan general hospital ministry of health and welfare, Taiwan, Taiwan, ⁴Department of Radiology, Taipei City Hospital, Taiwan, Taiwan

The aim of this study is to compare efficacy of Gd-EOB-DTPA enhanced-MRI and MRE in estimation of hepatic fibrosis stage with histopathologic correlation.

Temel Kaya Yasar¹, Cecilia Besa¹, Jad Bou Ayache¹, Octavia Bane¹, Maggie Fung², and Bachir Taouli^1
1Icahn School of Medicine at Mount Sinai, New York, NY, United States, ²GE Healthcare, New York, NY, United States

GRE based MRE pulse sequences are commonly used for liver studies. However, SE-EPI based MRE pulse sequences are attractive due to shorter acquisition time and higher SNR. However, clinical evidence whether EPI is equivalent to GRE-MRE remains to be proven. In this study, we compared liver stiffness using GRE and EPI MRE in 9 patients. In parallel to stiffness measurements two radiologist assessed the quality MRE from wave images and confidence maps. While excellent agreement was found between methods, EPI-MRE was found to be of higher quality while significantly shorter in acquisition time.

Chen-Te Chou^1,2, Wen-Pei Wu², Yi-Jun Wang², and Ran-Chou Chen^2,3
1Radiology, Chang-Hua Christian hospital, Chang-Hua, Chang-Hua, Taiwan, ²Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan, Taiwan, ³Radiology, Taipei City Hospital, Taipei, Taiwan, Taiwan

According to guidelines published by AASLD, treatment of underlying disease should be considered if patients with significant hepatic fibrosis (fibrosis stage ¡Ý 2). Long-term therapy might result in a regression of fibrosis. Therefore, differentiating between mild fibrosis (fibrosis stage ¡Ü 1) and significant fibrosis is very important to establish an effective treatment strategy. Our results show that MR elastography had better diagnostic value than acoustic radiation force impulse (ARFI) ultrasonography in differentiating mild fibrosis from significant fibrosis. In conclusion, MRE provided higher diagnostic performance than ARFI in differentiating significant hepatic fibrosis (stage¡Ý F2) from mild fibrosis.

Kengo Yoshimitsu¹, Atsushi Nozaki², and Richard L Ehman^3
1Radiology, Fukuoka University, Fukuoka, Fukuoka, Japan, ²GE Healthcare, Tokyo, Japan, ³Mayo Clinic, Minessota, United States

In assessing the fibrosis grades of the liver in patients with chronic liver diseases, 3.0T MR elastography with multi-model direct inversion algorithm provides stiffness map with less image defects, comparable measurable areas, and slightly less stiffness value of the liver, as compared to that with conventional multi-scale direct inversion algorithm.

YOSHIHIKO FUKUKURA¹, Koji Takumi¹, Toshikazu Shindo¹, Tomokazu Umanodan¹, Aya Umanodan¹, Junichi Ideue¹, Hiroto Hakamada¹, Kiyohisa Kamimura¹, Masanori Nakajo¹, and Takashi Yoshiura^1
1Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Kagoshima, Japan

We evaluated whether cytoplasmic lipids in pancreatic neuroendocrine tumors (NETs) can be identified on chemical shift MRI and clarify CT and MRI characteristics of lipid-containing pancreatic NETs. Cytoplasmic lipids were histopathologically observed in 15 of 34 NETs. Four of the 15 lipid-containing NETs exhibited high signal on subtraction chemical shift MRI, and signal intensity index of lipid-containing NETs was significantly higher than that of the non–lipid-containing NETs. Lipid-containing NETs had similar appearances to non–lipid-containing NETs on CT and conventional MRI. Pancreatic NETs should be included in the differential diagnosis whenever chemical shift MRI demonstrates lipid components within pancreatic tumors.

Gavin Hamilton¹, Michael S Middleton¹, William M Haufe¹, Jonathan C Hooker¹, Yesenia Covarrubias¹, Rohit Loomba², and Claude B Sirlin^1
1Department of Radiology, UC San Diego, San Diego, California, United States, ²Department of Medicine, UC San Diego, San Diego, California, United States

We developed a rapid multi-TR, multi-TE ¹H MRS sequence for in vivo hepatic fat quantification and characterization that acquires 32 single-average spectra in a single breath-hold. We examined the intra-examination repeatability of the sequence by repeating it three times in the same location without patient repositioning. The study showed that this single-breath-hold, multi-TR, multi-TE sequence can measure liver water T1 and T2, fat T2, and proton density fat fraction with high repeatability. Repeatability for fat T1 was modest.

Gavin Hamilton¹, Michael S Middleton¹, Alexandra N Schlein¹, Catherine A Hooker¹, Lisa Clark¹, Rohit Loomba², and Claude B Sirlin^1
1Department of Radiology, UC San Diego, San Diego, California, United States, ²Department of Medicine, UC San Diego, San Diego, California, United States

We developed a rapid multi-TR, multi-TE ¹H MRS sequence for in vivo hepatic fat quantification and characterization that acquires 32 single-average spectra in a single breath-hold. Here we compare the estimates of water and fat T2 and proton density fat fraction (PDFF) given by the multi-TR, multi-TE sequence with those given by the current MRS standard: a long-TR, multi-TE sequence. We find good agreement between the sequence estimates of PDFF and water T2. However there is little agreement for fat T2.

Xiaodong Zhong¹, Jie Deng^2,3, Brian M. Dale⁴, Cynthia K. Rigsby^2,3, and Mark H. Fishbein^5
1MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States, ²Department of Medical Imaging, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, United States, ³Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, ⁴MR R&D Collaborations, Siemens Healthcare, Cary, NC, United States, ⁵Division of Gastroenterology, Hepatology, and Nutrition, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, United States

In this work, a fat quantification mapping technique was evaluated in pediatric patients with suspected or identified NAFLD. This technique was capable of providing whole liver fat quantification in a single breath-hold and accounting for various factors such as T2* decay, T1 bias, multi-peak fat modeling. Preliminary results showed consistency between the proton density fat fraction results measured with this mapping approach and a previously validated ROI fitting method. This fat quantification mapping technique may have great potential for efficiently evaluating the hepatic steatosis for liver diseases in pediatric patients.

Roberto Salvati^1,2, Pierre-Antoine Eliat³, Orlando Musso^4,5, Christine Perret⁶, Eric Hitti^1,2, Marie Sicard^4,5, Herve Saint-Jalmes^1,2, and Giulio Gambarota^1,2
1LTSI, Université de Rennes 1, Rennes, France, ²INSERM, UMR 1099, Rennes, France, ³PRISM-Biosit CNRS UMS 3480, Université de Rennes 1, INSERM UMS 018, Rennes, France, ⁴Université de Rennes 1, Rennes, France, ⁵Institut National de la Santé et de la Recherche Médicale, Unit 991, Liver Metabolisms and Cancer, Rennes, France, ⁶Oncogenèse de l'épithélium digestif, INSERM UMRS 1016, Institut Cochin, Paris, France

Fat fraction (FF) and T2* relaxation time are important biomarkers in a number of pathologies (metabolic syndrome, hemochromatosis, etc.). The IDEAL approach (Iterative Decomposition with Echo Asymmetry and Least squares estimation) allows the joint estimation of both FF and T2*. A parameter of this algorithm is the number of echoes to be acquired for an optimal reconstruction of the outputs (FF and T2*). The aim of the current work is to compare the fat fraction as well as T2* values calculated with the 6-echo and 15-echo reconstruction on mice at 4.7T.

Sarah Keller¹, Bjoern Schoennagel¹, Zhiyue Jerry Wang², Regine Grosse³, Peter Nielsen⁴, Gerhard Adam¹, Roland Fischer¹, and Jin Yamamura^1
1Diagnostic and Interventional Radiology, University Medicine Hamburg Eppendorf, Hamburg, Germany, ²Radiology, Children's Medical Center Dallas, Dallas, Texas, United States, ³Pediatric Hematology and Oncology, University Medicine Hamburg Eppendorf, Hamburg, Germany, ⁴Institute of Biochemistry and Molecular Biology, Center of Experimental Medicine, Hamburg, Germany

Hereditary hemochromatosis (HH) is frequently associated with cardiomyopathy and iron accumulation in the heart beyond increased hepatic iron concentration (HIC). Measurements of cardiac and hepatic iron concentration in patients with HH are rare (Olson et al, 1987) and sporadic cases seem to be reported less frequently. MRI-R2* Relaxometry combined with Biosusceptometry was performed to assess cardiac, hepatic and pancreatic iron accumulation and relative fat/water content in 7 homozygotes with HH (C282Y: n=4, H63D: n=3).

Keitaro Sofue^1,2, Xiaodong Zhong³, Marcel Dominik Nickel⁴, Brian Marshall Dale⁵, and Mustafa Rifaat Bashir^1
1Radiology, Duke University Medical Center, Durham, NC, United States, ²Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan,³Siemens Healthcare, Atlanta, GA, United States, ⁴Siemens Healthcare, Erlangen, Germany, ⁵Siemens Healthcare, Morrisville, NC, United States

Repeatability of MRI-based liver fat and iron quantification using a multistep adaptive fitting algorithm.

Peter A. Hardy¹ and Jimmy Lee^1
1Radiology, University of Kentucky, Lexington, Kentucky, United States

Using an oil-water phantom with varying concentration of iron oxide designed to span the range encountered from normal to severe iron overload we tested Dixon Vibe to estimate fat-water content. We also developed a method to improve the estimate by correcting for T1 relaxation.

Bing Wu¹, Xinhuai Wu¹, Wenbo Zhang², Dandan Zheng³, Mingmei Ge¹, Xiao Li¹, and Yingkui Zhang^3
1Radiology Dept., Beijing Military General Hospital, Bejing, Beijing, China, ²Nephrology Dept., Beijing Military General Hospital, Bejing, Beijing, China, ³GE Healthcare China, Beijing, China

The aim of our work was to verify hepatic iron stores in uremic patients on dialysis as measured by liver R2* value from multi-echo iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) gradient-echo (GRE) magnetic resonance (MR) imaging.

Arthur Peter Wunderlich^1,2, Meinrad Beer¹, Peter Bernhardt³, Holger Cario⁴, Vinzenz Hombach³, Reinhard Meier¹, Wolfgang Rottbauer³, Stefan Andreas Schmidt¹, and Volker Rasche^3
1Clinic for Diagnostic and Interventional Radiology, Univ.-Clinic Ulm, Ulm, Germany, ²Section for Experimental Radiology, Univ.-Clinic Ulm, Ulm, Germany,³Clinic for Internal Medicine II - Cardiology, Univ.-Clinic Ulm, Ulm, Germany, ⁴Clinic for Pediatrics, Univ.-Clinic Ulm, Ulm, Germany

Since existing methods for determining Liver Iron Content (LIC) are based on Signal Intensity Ratio (SIR), we studied compatibility of SIR values between scanners from different vendors. Patients suspected for liver iron overload were examined at two different scanners the same day at 1.5 T. SIR values of in-phase GRE images calculated from three liver ROIs and two in paraspinal muscles, and LIC calculated using SIR obtained from both scanners were compared by statistical methods. SIR values showed good correlation but didn’t match properly. However, calculated LIC values were in good agreement between scanners, especially when working with RF spoiling.

Jin Yamamura¹, Sarah Keller¹, Björn Schönnagel¹, Regine Grosse², Zhiyue Jerry Wang³, Peter Nielsen⁴, Gerhard Adam¹, and Roland Fischer^1,5
1Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, ²Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, ³Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States, ⁴Biochemistry, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, ⁵Department of Radiology, Children's Hospital & Research Center Oakland, Oakland, California, United States

This study aims to determine the pancreatic iron and fat content in patients with iron overload.Highest iron and fat content was found in the pancreatic tail and pancreatic R2* correlated with cardiac iron deposition. Besides iron accumulation, fatty degeneration might be an additional risk factor for the development of diabetes and might also explain the early onset of diabetes in these patients.

Ronald Ouwerkerk¹ and Ahmed M Gharib^1
1The Biomedical and Metabolic Imaging Branch, NIDDK/NIH, Bethesda, MD, United States

A relaxation corrected fat fraction (ff) was measured in the human pancreas in one breath-hold, avoiding breathing motion artifacts. Volume and position of the pancreas make the measurement within one breath-hold challenging, but using short repetition rates a series of TE could be recorded with signal averaging in one breath hold. Estimates of water and fat T1s were incorporated by recording fully relaxed scans and used for saturation correction of the signals. Twenty subjects were examined yielding T2 and T1 corrected ff measurements the human pancreas and estimated of the T1 and T2 of pancreatic water and fat signals.

Tania Buehler¹, Lia Bally², Ayse Sila Dokumaci¹, Christoph Stettler², and Chris Boesch^1
1Depts. Radiology and Clinical Research, University Bern, Bern, Switzerland, ²Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital Bern, Bern, Switzerland

Glycogen metabolism plays a major role in glucose homeostasis in healthy (HEAL) and type 1 diabetes mellitus (T1DM) subjects. Despite the widespread use in metabolic research of MRS to measure glycogen, there is currently scarce data on its variability in T1DM subjects. Based on non-invasive natural abundance 13C MRS the present study investigated longitudinal reproducibility of hepatic and myocellular glycogen stores in healthy (CV 12%, 16% respectively) and T1DM (CV 16%, 9% respectively) subjects following prior a diet- and activity-standardization protocol. The findings can have important implications on e.g. the design of interventional trials assessing exercise-related fuel metabolism in T1DM.

Antonella Meloni¹, Paolo Ricchi², Paolo Preziosi³, Vincenzo Positano¹, Maria Chiara Resta⁴, Gennaro Restaino⁵, Antonino Vallone⁶, Maria Giovanna Neri¹, Graziella Filati⁷, Anna Pietrapertosa⁸, Petra Keilberg¹, and Alessia Pepe^1
1CMR Unit, Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy, ²UOSD Centro per le Microcitemie, AORN Cardarelli, Napoli, Italy, ³U.O.C. Diagnostica per Immagini e Interventistica, Policlinico “Casilino", Roma, Italy, ⁴Struttura Complessa di Radiologia, OSP. SS. Annunziata ASL Taranto, Taranto, Italy, ⁵Istituto di Radiologia, Università Cattolica del Sacro Cuore, Campobasso, Italy, ⁶Istituto di Radiologia, Az. Osp. "Garibaldi" Presidio Ospedaliero Nesima, Catania, Italy,⁷Pediatria, Ospedale “G. Da Saliceto”, Piacenza, Italy, ⁸Policlinico di Bari, Servizio Regionale Talassemie, Bari, Italy

In a large cohort of regularly transfused thalassemia patients, the presence of extramedullary hematopoiesis (EMH) assessed by MRI was not rare. EMH was associated to a heart thalassemia intermedia like pattern (reduced cardiac iron loading and stigmata of high cardiac output state) despite the transfusional regimen

Alessandra Bierwagen^1,2, Bettina Nowotny^1,2, Julia Szendroedi^1,3, Karsten Müssig^1,3, Michael Roden^1,3, and Jesper Lundbom^1,2
1Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University, Duesseldorf, Germany, ²German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Duesseldorf, Germany, ³Department of Endocrinology and Diabetology, University Hospital Duesseldorf, Germany

This study compared intrasubject changes in lipid unsaturation in yellow and red bone marrow and correlated these parameters to physical activity, age and BMI. Long-TE ¹H MRS spectra were acquired in the bone marrow of the femur of 9 female subjects. The mean unsaturation index of the red bone marrow was significantly lower than the unsaturation index of yellow bone marrow. RBM unsaturation correlated with the BAECKE sport index. Furthermore the fat content of the red bone marrow correlated with age.

Patrick J Bolan^1,2, Steen Moeller¹, Gregory J Metzger^1,2, Michael Garwood^1,2, Douglas Yee^2,3, and Michael T Nelson^1,2
1Radiology, University of Minnesota, Minneapolis, MN, United States, ²Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States,³Medicine, University of Minnesota, Minneapolis, MN, United States

Magnetic resonance spectroscopy (MRS) can provide clinically valuable metabolic information for diagnosing and treating breast cancer, but current acquisition techniques need improvement. Single-voxel MRS (SVS) gives good quality but requires expertise to acquire, whereas chemical shift imaging (CSI) methods are easier to acquire but give lower quality spectra. Our long-term goal is to use a technique known as Spectral Localization by IMaging (SLIM) to reconstruct acquired CSI data, producing high-quality spectra comparable to SVS but with the robust acquisition of CSI. This work presents initial results in breast cancer showing SLIM spectra that are comparable or better than CSI.

Tianyong Xu¹, Qian Jiang¹, Bing Wu¹, Kai Xu², and Zhenyu Zhou^1
1GE Healthcare China, Beijing, Beijing, China, ²The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China

Knowledge of fat content in liver is not only useful for hepatic disease diagnosis but also valuable in monitoring recovery and assessing treatment effectiveness. Dual echo 2D SPGR is a routinely used sequence for obtaining the quantitative fat fraction by deriving the signal intensity ratios of in-phase and out-of-phase images. However it may fail for patients with liver iron-overloading that leads to shortened T2*, and the in-phase images suffer from low SNR that affects the accuracy of calculation. We investigate if the LAVA-flex sequence may be an iron overloading immune method for fat fraction assessment in patients diagnosed with hematopathy.

Ting Yin¹, Walter Coudyzer², Ronald Peeters², Yewei Liu¹, Marlein M. Cona¹, Yuanbo Feng¹, Jie Yu², Steven Dymarkowski², Raymond Oyen², and Yicheng Ni^1,2
1Theragnostic Laboratory, KULeuven, Leuven, Flemish Brabant, Belgium, ²Department of Radiology, KULeuven, Leuven, Flemish Brabant, Belgium

In this study, we intended to image rat pancreas in situ by using the state-of-the-art clinical MRI and CT scanners with the assistance of intra-pancreatic contrast enhancement. Detailed imaging landmarks and morphology of rat pancreas were measured, described and presented with 3D rendering. Meanwhile, with the help of clear recognition of rat pancreas anatomy in situ, attempts were made for imaging of native pancreatic landmarks in vivo without any contrast enhancement.

Marina-Portia Anthony¹, Stuart Bentley-Hibbert¹, Anuradha S Shenoy-Bhangle¹, Elizabeth Hecht¹, Benjamin Samstein², and Martin R Prince^1
1Abdominal Division, Department of Radiology, Columbia University Medical Center, New York, NY, United States, ²Department of Surgery, Columbia University Medical Center, New York, NY, United States

Orthotopic Liver Transplant (OLT) was traditionally performed using conventional caval reconstruction with end-to-end anastomosis. In recent years however, the piggyback technique (PB) with preservation of the recipient retrohepatic IVC and side-to-side anastomosis of the donor IVC to a cuff fashioned from the recipient hepatic veins, has gained popularity. The purpose of this study is to report the variety of MRI appearances of the donor IVC stump produced as a result of this new technique, which may cause confusion in the uninformed reader.

Hepatobiliary II

Wednesday, 3 June 2015

Akiyoshi Yamamoto¹, Hiroki Matoba¹, Yuji Shintani¹, Daiji Uchiyama¹, Seigo Yoshida¹, Katsumi Nakamura^1,2, and Mitsue Miyazaki^3
1Radiology, Tobata Kyoritsu Hospital, Kitakyusyu, Fukuoka, Japan, ²Radiology, Hikari Central Hospital, Hikari, Yamaguchi, Japan, ³Toshiba Medical Research Institute USA, Vernon Hills, Illinois, United States

A non-gated single 15-sec breath-hold 3D-MRCP technique using bSSFP was developed and the feasibility of the proposed method for the visualization of bile ducts was compared using respiratory gated 3D-FSE MRCP with several minutes of scan time. The single breath-hold bSSFP-MRCP technique was optimized in flip angle and the number of segmentations to obtain good contrast of bile fluid over blood signal with maintaining the 15 sec breath-holding. The proposed bSSFP-MRCP technique gave equal to FSE-MRCP in the visualization of common bile duct and intrahepatic bile duct.

Jinrong QU¹, Xiang Li¹, lifeng wang¹, Junpeng Luo¹, Cuicui Liu¹, and Hailiang Li^1
1Radiology, the Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, HENAN, China

The diffusion parameters calculated from multi-b DW imaging could promise higher accuracy than regular ADC calculated from two-b DW imaging for the differential diagnosis of HCCs and cholangiocarcinomas, but could not provide additional information for the distinguish of HCCs and cholangiocarcinomas from metastases.

Kazuya Yasokawa¹, Akira Yamamoto¹, Tsutomu Tamada¹, Akihiko Kanki¹, Atsushi Higaki¹, Yasufumi Noda¹, and Katsuyoshi Ito^1
1Radiology, Kawasaki Medical School, Kurashiki, Okayama, Japan

This study evaluated the influence of oral ingestion in secretory flow dynamics of physiological pancreatic juice within the main pancreatic duct in 38 healthy volunteers by using cine-dynamic MRCP and a spatially selective IR pulse non-invasively. The median secretion grade of pancreatic juice at 5-19 minutes after ingestion was significantly higher than that before ingestion. Secretion grade of pancreatic juice showed a maximum peak at 19 minutes after ingestion, and then, began to gradually decline, compared with that of maximum peak value. This technique may have a potential to evaluate physiological pancreatic exocrine function in postprandial state.

xinghui li¹, xiaoming zhang², and jiani hu^3
1Department of Radiology, Affiliated Hospital of North Sichuan Medical College, nanchong, sichuan, China, ²Department of Radiology, Affiliated Hospital of North Sichuan Medical College, sichuan, China, ³Department of Radiology, Wayne State University, MI, United States

DTI can noninvasively provide functional information that indirect assessment of cellularity and the heterogeneity of the biology of HCC. An evaluation of the clinical effectiveness of using DTI to study HCC has thus far not been reported, moreover, no reports on the optimized parameters of liver DTI have been published. Therefore, the purpose of this study is to determine a set of optimized parameter and the feasibility of evaluating HCC using DTI. Major results of this study were: 1) There was no significant change in liver IQ with increased NED (P>0.05), whereas the liver IQ decreased significantly with increased B values (P<0.05); 2) NED=9 and B value = 500s/mm2 were chosen as the optimal set of parameters for liver; 3) Using the new optimized DTI sequence, ADC value of HCC lesions were significantly lower than those of normal right liver (1.30+ 0.34 vs 1.52+ 0.27¡Á10−3mm2/s, P=0.013) and the mean FA value of HCC lesions was significantly higher than normal right liver (0.42+ 0.11vs 0.32 + 0.10, P=0.004). Results demonstrate that the diffusion in HCC lesions should be restricted and anisotropic, which points out low ADC value and high FA value provide useful information about celluar changes induced by HCC, therefore, DTI can detect cellular changes induced by HCC in a typical clinical setting, HCC lead to higher FA values and lower ADCs on DTI than healthy liver.

Eun-Suk Cho¹, Dahye Lee¹, and Jeong-Sik Yu^1
1Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea

The intravoxel incoherent motion (IVIM) MR imaging can distinguish bland thrombus from neoplastic thrombus in the portal vein in patients with cirrhosis or hepatocellular carcinoma. Pseudo-diffusion coefficient (micro-perfusion) of neoplastic thrombus was significantly higher than that of bland thrombus, which might be due to capillary blood flow within neoplastic thrombus.

Yunjung Lee¹ and Hyeonjin Kim^1,2
1Radiology, Seoul National University Hospital, Seoul, Korea, ²Biomedical Sciences, Seoul National University, Seoul, Korea

Given the potential confounding effect of fat on apparent diffusion coefficient (ADC) in the liver in diffusion MRI, we have assessed diffusion tensor imaging (DTI) in liver fibrosis with minimal effect of fat on ADC and fractional anisotropy (FA) at 9.4T by employing a suitable animal model. Our results demonstrate that at b=0 and 500 s/mm2, FA may be more sensitive to mild-to-moderate liver fibrosis than ADC. In addition to ADC as demonstrated elsewhere, FA may also be sensitive to hepatic fat content, and therefore need to be carefully interpreted in the presence of fatty liver.

Lifen Xie^1,2, Changhong Liang¹, Zaiyi Liu¹, Queenie Chan³, and Yingjie Mei^4
1Department of Radiology, Guangdong Academy of Medical Sciences/Guangdong General Hospital, Guangzhou, Guangdong, China, ²Southern Medical University, Guangzhou, Guangdong, China, ³Philips Healthcare, HK, China, ⁴Philips Healthcare, Guangzhou, Guangdong, China

To quantify diffusion and perfusion characteristics of hepatocellular carcinoma (HCC) with both IVIM and DCE MRI, and to evaluate the correlation between the resulting parameters. 35 patients with cirrhosis and HCCs underwent IVIM and DCE-MRI scans. DCE-MRI parameters (Ktrans, kep, ve and vp) and IVIM parameters (D,D* and f) were obtained. The correlation between IVIM-DWI and DCE-MRI parameters of HCCs, and differences of IVIM-DWI parameters between liver parenchyma and HCCs were analyzed Paired-Samples T Test or Wilcoxon Test. The results demonstrated vp was inversely correlated with D in HCCs, and HCCs showed significantly lower ADC, D, f and D* values compared to liver parenchyma (P£¼0.001). IVIM-DWI provides parameters that are significantly different in HCC compared to liver parenchyma.

Yasunari Fujinaga¹, Masaaki Takahashi¹, Akira Fujita¹, Sachie Fujita¹, Shin Yanagisawa¹, Hideaki Hamano², Shigeyuki Kawa³, and Masumi Kadoya^1
1Department of Radiology, Shinshu University, School of Medicine, Matsumoto, Nagano, Japan, ²Department of Gastroenterology, Shinshu University Hospital, Matsumoto, Nagano, Japan, ³Center for Health, Safety, and Environmental Management, Shinshu University, Matsumoto, Nagano, Japan

On diffusion-weighted imaging (DWI), the variables except for apparent diffusion coefficient (ADC) value have not been analyzed to differentiate autoimmune pancreatitis (AIP) from pancreatic cancer (PC). We aimed to analyze which variable was useful to differentiate AIP from PC on DWI. In 42 AIP patients and 50 PC patients who underwent 3-T MRI including DWI, variables such as ADC value, ADC ratio (ADC_lesion/ADC_spleen), signal intensity (SI), SI ratio (SI_lesion/SI_spleen) were compared between AIP and PC. Among 4 variables, the ADC value was most useful for differentiation because its area under the curve was highest in the ROC analysis.

John J Hermans¹, Deniece Riviere¹, Marnix Maas¹, Monica Van Zanten², Tanya Bisseling³, Martin Gotthardt¹, and Kees Van Laarhoven^4
1Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, Gelderland, Netherlands, ²Pathology, Radboud University Medical Center, Nijmegen, Gelderland, Netherlands, ³Gastroenterology and Hepatology, Radboud University Medical Center, Nijmegen, Gelderland, Netherlands, ⁴Surgery, Radboud University Medical Center, Nijmegen, Gelderland, Netherlands

Retrospective analysis of 3T DWI-MRI was performed in 42 patients with a potentially resectable pancreatic tumour. Whole mount slices of the tumor were obtained from 10 resection specimens and graded according to Adsay, who uses a major and minor pattern of glandular differentiation, in analogy to Gleason for prostate adenocarcinomas. There was no significant correlation between mean ADC-values of PDAC, DWI-patterns, tumour stage, grade (Klöppel), size, presence of metastases or OS. There was no significant correlation between Adsay’s tumour grade and tumour stage or size. However, we found a nearly significant correlation between Adsay’s tumour grade and mean ADC (p=0,063).

Sabrina Doblas¹, Philippe Garteiser¹, Vincent Barrau^2,3, Magaly Zappa^1,2, Valérie Vilgrain^1,2, and Bernard E Van Beers^1,2
1U1149 - CRI, INSERM, Paris, France, ²Radiology, Beaujon Hospital, Clichy, France, ³CCN, Saint-Denis, France

The aim of our study was to assess the reproducibility of ADC at 3T in liver metastases of colorectal cancer in a two-center, cross-vendor configuration. The study was carried out with 5 patients bearing 19 tumors assessed on a 3T GE Discovery system, and 6 patients bearing 27 tumors assessed on a 3T Philips Ingenia system. Two acquisition protocols were used for test-retest: protocol A included 4 b values for ADC measurements, while protocol B included 10 b values for ADC measurements. Coefficients of reproducibility were calculated and compared. Reproducibility of ADC in colorectal liver metastases at 3T was similar between vendors, and comparable to previously reported figures at 1.5T. The best reproducibility was obtained for ADC measurements on the extended b space coverage acquisition protocol.

YOSHIHIKO FUKUKURA¹, Toshikazu Shindo¹, Tomokazu Umanodan¹, Tomoyuki Okuaki², Koji Takumi¹, Aya Umanodan¹, Junichi Ideue¹, Hiroto Hakamada¹, Kiyohisa Kamimura¹, Masanori Nakajo¹, and Takashi Yoshiura^1
1Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Kagoshima, Japan, ²Philips Healthcare, Tokyo, Japan

This study focused on the potential of apparent diffusion coefficient (ADC) histogram analysis on DWI to differentiate pancreatic adenocarcinoma from neuroendocrine tumor. Adenocarcinomas and neuroendocrine tumors were not significantly different in mean, skewness, or 25th, 50th, or 75th percentiles of ADC values calculated at any b-value combination derived from b-values of 0 and 200 s/mm2, 0 and 400 s/mm2, or 0 and 800 s/mm2. Variance, CV, and kurtosis of the ADC values were significantly higher in adenocarcinomas than in neuroendocrine tumors at all b-value combinations. Histogram analysis of ADC maps could be helpful in differentiating pancreatic adenocarcinomas from neuroendocrine tumors.

Sara C Lewis¹, Shingo Kihira¹, Cecilia Besa², Hongfa Zhu³, Swan Thung³, Kartik Jhaveri⁴, and Bachir Taouli^5
1Radiology, Mount Sinai Medical Center, New York, NY, United States, ²Translational and Molecular Imaging Institute, Mount Sinai Medical Center, New York, NY, United States, ³Pathology, Mount Sinai Medical Center, New York, NY, United States, ⁴Radiology, University Health Network Mt. Sinai and Womens' College Hospital, Toronto, Ontario, Canada, ⁵Radiology, Translational and Molecular Imaging Institute, Mount Sinai Medical Center, New York, NY, United States

This study evaluates qualitative and quantitative SS EPI diffusion-weighted imaging for assessment of intrahepatic cholangiocarcinoma. Initial results demonstrate high lesion conspicuity with approximately a third of lesions showing a target appearance. ADC of grade 3 tumors was lower than those of grade 2 without reaching significance. These preliminary results suggest that DWI is useful for cholangiocarcinoma detection, however ADC quantification for assessing tumor grade needs further validation.

Oi Lei Wong¹, Gladys Goh Lo², Wing Wa Li², Jing Yuan³, Raymond Lee², and Michael D. Noseworthy^4
1Department of Medical Physics and Applied Radiation Science, McMaster University, Hamilton, Ontario, Canada, ²Department of Diagnostic & Interventional Radiology, Hong Kong Sanatorium & Hospital, Hong Kong, China, ³Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China, ⁴Department of Electrical and Computer Engineering, McMaster Univeristy, Hamilton, Ontario, Canada

Liver DTI metrics consistency is closely related to its usefulness in treatment outcome evaluation and disease monitoring. In this study, the inter-session and intra-session repeatability of DT metrics were evaluated. Based on our results, liver DT metrics were repeatable (for both inter-session and intra-session) when large ROI was used. Also, no improvement in DT metrics repeatability was observed when number of gradient directions increased.

Young Kon Kim^1,2, Peng Hu¹, Daniel Margolis¹, Steven Raman¹, David Lu¹, J. Paul Finn¹, and Kyunghyun Sung^1
1Radiological Sciences, University of California, Los Angeles, Los Angeles, CA, United States, ²Radiology, Samsung Medical Center, Seoul, Korea

Recent studies have highlighted the potential of ferumoxytol as an alternative to gadolinium based contrast agents (GBCAs). Here, we demonstrate the imaging features of liver imaging after the administration of ferumoxytol with emphasis on potential for liver metastasis workup.

Matthew DF McInnes^1,2, Rebecca M Hibbert¹, Joao Inacio¹, and Nicola Schieda^1
1Radiology, University of Ottawa, Ottawa, Ontario, Canada, ²Ottawa Hospital Research Institute, Ottawa, Ontario, Canada

This is a systematic review evaluating the diagnostic accuracy of hepatobiliary phase gadoxetic acid-enhanced MRI of the liver for diagnosis of focal nodular hyperplasia and hepatocellular adenoma.

Inhwan Jeon¹, Dahye Lee¹, Eun-Suk Cho¹, and Jeong-Sik Yu^1
1Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea

On Gd-EOB-DTPA-enhanced MRI for detection of HCC, 10-min delayed hepatocyte phase imaging using a 30° flip angle had higher or similar lesion-to-liver CNR and detection sensitivity, compared to 20-min delayed hepatocyte phase imaging with 10° or 30° flip angle. This result indicates that 10-min delayed hepatocyte phase imaging with a 30° FA could replace 20-min delayed hepatocyte phase imaging with better or similar diagnostic performance for the detection of HCC and also allows 10 minutes of time-saving.

Alexander Ciritsis¹, Daniel Truhn¹, Nils Krämer¹, and Christiane K. Kuhl^1
1Department of Diagnostic and Interventional Radiology, RWTH University Hospital Aachen, Aachen, NRW, Germany

Gadoxetic acid (Gd-EOB-DTPA) has become the clinical standard in diagnostic liver imaging, and provides information about the function of hepatic cells. In this study we employ multiple flip angle measurements in7 patientsto determine T1 times of liver tissue and use these to calculate the absolute concentration of Gd-EOB-DTPA in the liver 25min after administration. This can be used to image liver function.

Utaroh Motosugi^1,2, Peter Bannas^1,3, Diego Hernando¹, Mahdi Salmani Rahimi^4,5, James H. Holmes⁶, and Scott B. Reeder^1,7
1Radiology, University of Wisconsin, Madison, Wisconsin, United States, ²Radiology, University of Yamanashi, Chuo-shi, Yamanashi, Japan, ³Radiology, University Hospital Hamburg-Eppendorf, Humburg, Germany, ⁴Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, United States, ⁵Radiology, Stanford University, Stanford, Calfornia, United States, ⁶5Global MR Applications and Workflow, GE Healthcare, Madison, Wisconsin, United States, ⁷Medical Physics, University of Wisconsin, Madison, Wisconsin, United States

Gadoxetic acid is a hepatobiliary contrast agent with important clinical applications. However, the approved dose (0.025mmol/kg) is 1/4 that of traditional MR contrast agents, that may result in insufficient contrast especially for dynamic phase imaging. For this reason, many institutions have adopted the use of higher doses as a clinical standard. This motivated a systematic evaluation of higher dosing of gadoxetic acid with relaxometry. In this study, we show that 0.05mmol/kg gadoxetic acid leads to significantly higher SNR and CNR performance than 0.025mmol/kg. Further, a 10-minute delay may be feasible for hepatobiliary-phase imaging when using 0.05mmol/kg of gadoxetic acid.

Ke Wang¹, Xiaochao Guo¹, Xuedong Yang¹, and Xiaoying Wang^1
1Radiology Department, Peking University First Hospital, Beijing, Beijing, China

This is a retrospective study evaluating the interreader variability between radiologists by using the major features of the Liver Imaging- Reporting and Data System (LI-RADS )1 version 2014 in patients with liver cirrhosis induced by HBV infection.

Michael Z Liu¹, Sachin Jambawalikar¹, Helen R Remotti¹, Stuart W Weisberg¹, Pascal Spincemaille², Henry Rusinek³, Artem V Mikheev³, Martin Prince¹, Donald Garmon¹, Yanghee Woo¹, John Chabot¹, and Elizabeth M Hecht^1
1Columbia University, New York, NY, United States, ²Cornell University, New York, United States, ³New York University, New York, United States

In this study, we assess the agreement between quantitative imaging parameters derived from dynamic contrast enhanced (DCE) MRI and mean vascular density and percent fibrosis in 15 participants with pancreatic cancer.Spiral k-space 3D T1w GRE was used quantitatively in DCE-MRI permitting whole liver/pancreas coverage with sub 3 second temporal resolution. Ve and kep may serve as biomarkers of fibrosis and MVD while Ktrans does not. This may be due to the characteristic high desmoplasia and relatively low perfusion of pancreatic adenocarcinomas. Higher temporal resolution can be extracted from this data and alternative kinetic modeling may further bring out the unique features of pancreatic adenocarcinoma. Preliminary results in humans comparing DCE metrics with Gadofosveset trisodium to extracellular agents are presented.

Takayuki Masui¹, Motoyuki Katayama¹, Yuji Iwadate², Naoyuki Takei², Kang Wang³, Dan Rettmann³, Kimihiko Sato¹, Kei Tsukamoto¹, Kenichi Mizuki¹, Maho Hayashi¹, and Masayoshi Sugimura^1
1Radiology, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka, Japan, ²Global MR Applications and Workflow, GE Healthcare Japan, Hino, Tokyo, Japan,³Global MR Applications and Workflow, GE Healthcare, WI, United States

The purpose was to evaluate the feasibility of dynamic Gd-contrast study using fast 3D imaging sequence, DISCO under free-breathing with navigator technique for evaluation of pancreatobiliary diseases including the liver. Dynamic contrast MR imaging of the pancreatohepatobiliary regions could be performed under free-breathing with acceptable image quality and temporal resolutions. This technique may be useful for evaluations of the patients who cannot hold their breaths such as elderly patients, unconscious patients or children and may improve information acquired from single MR study with contrast medium.

Hersh Chandarana^1,2, Li Feng^1,2, Justin Ream¹, Annie Wang¹, James Babb¹, Kai Tobias Block^1,2, Mary Bruno¹, Daniel K Sodickson^1,2, and Ricardo Otazo^1,2
1Radiology, Center for Biomedical Imaging, NYU School of Medicine, New York, NY, United States, ²Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), NYU School of Medicine, New York, NY, United States

This work applies the novel XD-GRASP technique for continuous free-breathing motion-sorted golden-angle radial MRI to the examination of patients undergoing liver MRI using the hepatobiliary contrast agent Gd-EOB-DTPA, which is known to result in suboptimal quality of the arterial phase. Continuously acquired k-space data were sorted into contrast-enhancement and respiratory phases, and reconstructed using a compressed sensing approach that exploits sparsity along the dynamic dimensions. Our results demonstrate that arterial-phase XD-GRASP reconstructions had superior image quality compared to conventional GRASP, as well as to standard breath-hold examinations. XD-GRASP has the potential to improve imaging in patients undergoing Gd-EOB-DTPA enhanced MRI.

Puneet Sharma¹, Kevin Johnson², Alto Stemmer³, Bobby Kalb¹, and Diego R Martin^1
1Medical Imaging, University of Arizona, Tucson, Arizona, United States, ²Siemens Healthcare, Tucson, Arizona, United States, ³Siemens Healthcare, Erlangen, Germany

The purpose of this investigation was to implement a radial 3D GRE using a golden angle acquisition scheme and KWIC reconstruction for motion-resistant hepatic arterial-phase imaging. These preliminary results show observable suppression of motion artifacts, making this acquisition strategy an effective alternative to cartesian 3D GRE for free-breathing dynamic liver imaging

Takao Goto¹, Shiro Ozaki², Yuji Iwadate³, Kunihiro Miyoshi¹, Koji Uchida⁴, Hajime Kitagaki⁴, and Hiroyuki Kabasawa^3
1MR Engineering, GE Healthcare, Hino-shi, Tokyo, Japan, ²Shimane University Hospital, Izumo-shi, Shimane, Japan, ³Global MR Applications and Workflow, GE Healthcare, Hino-shi, Tokyo, Japan, ⁴Department of Radiology, Shimane University Faculty of Medicine, Izumo-shi, Shimane, Japan

In our previous study, we proposed a method for automated navigator tracker (ANAV) positioning to improve operator workflow. In order to progress this work further, we applied an ANAV to a prospective navigator correction. The T1 weighted fat-saturated 3D fast SPGR sequence is used for the DCE-MRI, which acquired pre-contrast, arterial, portal, equilibrium and two delayed phase images with the breath-holding method. We set the top position of the liver as a reference in the pre-contrast images. The navigator tracked this position in successive phase images. Forty patients were tested, producing satisfactory results and helping to identify a limitation.

Gastrointestinal MRI, Diabetes, Nutrition, Metabolism, Hepatobiliary

Wednesday, 3 June 2015

Feng Wang^1,2, Ke Li^1,2, Keiko Takahashi^3,4, E. Brian Welch^1,2, Zhongliang Zu^1,2, Daniel Gochberg^1,2, Raymond C. Harris^3,4, C. Chad Quarles^1,2, Takamune Takahashi^3,4, and John C. Gore^1,2
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, ²Institute of Imaging Sciences, Vanderbilt University, Nashville, TN, United States, ³Vanderbilt O'Brien Mouse Kidney Physiology and Disease Center, Vanderbilt University, TN, United States, ⁴Division of Nephrology and Hypertension, Vanderbilt University, TN, United States

Diabetic nephropathy (DN) is the leading cause of renal failure. Murine models of DN are routinely used to evaluate the mechanistic aspects of this disease. The objective of this study was to 1) validate and evaluate the reproducibility of quantitative magnetization transfer (qMT), chemical exchange saturation transfer (CEST) and fat imaging at 7T for assessing diabetic kidney disease and 2) determine the potential of these quantitative MRI approaches to distinguish moderate and advanced DN. The long-term goal is to understand the development and progression of fibrosis and lipid and glucose deposition in accelerated diabetic kidney disease.

Kevin J Sinclair¹, Lanette J Friesen-Waldner¹, Colin M McCurdy¹, Curtis N Wiens², Trevor P Wade^1,3, Barbra de Vrijer⁴, Timothy RH Regnault^4,5, and Charles A McKenzie^1,3
1Medical Biophysics, University of Western Ontario, London, Ontario, Canada, ²Radiology, University of Wisconsin, Madison, Wisconsin, United States,³Robarts Research Institute, University of Western Ontario, London, Ontario, Canada, ⁴Obstetrics and Gynaecology, University of Western Ontario, London, Ontario, Canada, ⁵Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada

Over-nourishment of a fetus during development has been shown to increase the risk of metabolic and cardiovascular disease in adulthood. The purpose of this study was to identify anatomical differences between fetal guinea pigs subjected to a maternal ‘Western Diet’ and a synthetic ‘Control Diet’. T₁- and T₂-weighted, as well as IDEAL water-fat images of pregnant guinea pigs (N = 12) were used to obtain fetal organ volumes and quantify fetal fat deposition. Western Diet fetuses were seen to have increased liver volume and increased fat deposition in the liver and in adipose tissue compared to controls.

Ana Francisca Soares¹, Hongxia Lei², and Rolf Gruetter^1
1LIFMET, EPFL, Lausanne, Vaud, Switzerland, ²Radiology, University of Geneva, Geneva, Geneva, Switzerland

Hepatic lipids of healthy and streptozotocin-diabetic mice were characterized by ¹H-MRS in vivo with ultra-short TE STEAM at 14.1T and compared to HR-MR measurements of liver extracts, which were strongly driven by membrane lipids. Streptozotocin injection reduced the hepatic lipid content by over one half, doubled the contribution saturated fatty-acyl (SFA) chains, and decreased the mean length of the lipid chains in the cytosolic pool. Membrane lipids were also enriched with SFA and shorter chains. These alterations are in line with abnormalities on lipid desaturation and elongation in streptozotocin-diabetic mice.

Alejandro Roldán-Alzate¹, Curtis N Wiens¹, Kevin M Johnson², Alan B Mcmillan¹, Oliver Wieben^1,2, Claude Sirlin³, and Scott B Reeder^1,2
1Radiology, University of Wisconsin - Madison, Madison, WI, United States, ²Medical Physics, University of Wisconsin - Madison, Madison, WI, United States,³Radiology, University of California San Diego, San Diego, CA, United States

NAFLD is an increasingly prevalent condition often encountered in patients with obesity. It is the most common type of chronic liver disease and a large and increasing number of NAFLD patients develop liver cirrhosis. In this study we evaluated the feasibility and describe preliminary observations of 4D Flow MRI to non-invasively assess portal hemodynamics in obese patients. Results show blood flow through Ao, PV and HA to be lower in obese patients than in healthy controls. The ability to non-invasively quantify mesenteric hemodynamics in these individuals suggests that 4D flow MRI may be suitable for use in future mechanistic studies of NAFLD pathogenesis, evolution, and response to therapeutic intervention.

Christian Cordes¹, Michael Dieckmeyer¹, Beate Ott², Jun Shen¹, Stefan Ruschke¹, Marcus Settles¹, Claudia Eichhorn², Jan S. Bauer¹, Hendrik Kooijman³, Ernst J. Rummeny¹, Thomas Skurk², Thomas Baum¹, Hans Hauner², and Dimitrios C. Karampinos^1
1Diagnostic and Interventional Radiology, Technische Universität München, München, Germany, ²Else Kröner Fresenius Center for Nutritional Medicine, Technische Universität München, München, Germany, ³Phillips Healthcare, Hamburg, Germany

Bone marrow is a fat depot that has recently attracted a considerable research interest due to its unique connections to metabolism and bone health. The present study examines the relationship between changes in bone marrow fat fraction (BMFF), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), liver fat and serum lipid levels after a four-week calorie restriction in twenty obese women. BMFF is shown to have smaller changes after the dietary intervention compared to SAT, VAT, liver fat and serum lipids. BMFF changes are also shown to be dependent on the abdominal tissue distribution before the dietary intervention.

Diego Hernando¹, William M. Haufe², Catherine A. Hooker², Alexandra Schlein², Tanya Wolfson³, Nathan S. Artz^1,4, Scott B. Reeder^1,5, and Claude B. Sirlin^2
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²Radiology, University of California, San Diego, San Diego, CA, United States,³Computational and Applied Statistics Laboratory, University of California, San Diego, San Diego, CA, United States, ⁴Radiological Sciences, Saint Jude Children's Research Hospital, Memphis, TN, United States, ⁵Medical Physics, University of Wisconsin-Madison, Madison, WI, United States

Chemical shift encoded techniques enable rapid fat and iron quantification over the entire liver, by mapping proton density fat fraction (PDFF) and R2* (=1/T2*), respectively. However, the relationship between liver PDFF and R2* in the absence of iron overload is not yet fully understood. The purpose of this study was to evaluate the relationship between liver PDFF and R2* in patients with histology-confirmed absence of iron overload. This works demonstrates a strong (r~0.8) correlation between liver PDFF and R2* in patients without iron overload. Future work is needed to fully characterize the source of this correlation.

Gaëlle Diserens¹, Maryam Seif¹, Laila Yasmin Mani², Daniel Fuster², Christoph Stettler³, Chris Boesch¹, Bruno Vogt², and Peter Vermathen^1
1Depts. Radiology and Clinical Research, University Bern, Bern, Switzerland, ²Dept. Nephrology, Hypertension and Clinical Pharmacology, University Hospital Of Bern, Bern, Switzerland, ³Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital Bern, Bern, Switzerland

The purpose of this study was 1) to optimize the MRS protocol for estimating ectopic renal lipids, 2) to determine in a pilot study the ectopic lipid content in obese patients with type 2 diabetes with the optimized protocol. The preliminary SVS results in obese patients with type 2 diabetes yielded ectopic lipid contributions of only 0.8±0.4%. Reliable fat estimations in renal tissue were obtained using a protocol optimized for ectopic lipid determination. The finding of low ectopic lipid content in few obese diabetic patients requires confirmation.

Venkatesh Gopalan¹, Navin Michael², S S Lee¹, Yaligar J¹, Bhanu Prakash KN¹, and S Sendhil Velan^1
1Singapore Bio-Imaging Consortium, BioMedical Sciences Institutes, Singapore, Singapore, ²Singapore Institute for Clinical Sciences, Singapore, Singapore

Saturated fatty acids promote increased energy partitioning towards fat storage, and reduced fat oxidation, which is marked by increased stearoyl coenzyme desaturase (SCD) activity and increased ectopic fat infiltration. Both the above changes are strongly linked to the pathogenesis of cardio-metabolic disorders. In the current study we have evaluated the relative effects of exercise and calorie restriction interventions on weight loss, liver fat, intramyocellular lipids in the skeletal muscle and SCD activity in obese male rats fed with a high saturated fat diet, using 1H magnetic resonance spectroscopy and Liquid Chromatography-Mass Spectrometry (LC-MS).

Jadegoud Yaligar¹, Bhanu Prakash KN¹, Brayn Tan², Swee Shean Lee¹, Venkatesh Gopalan¹, David Lawrence Silver², and S Sendhil Velan^1
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, Singapore, ²Signature Research Program in Cardiovascular & Met, Duke-NUS Graduate Medical School Singapore, Singapore, Singapore

Fat deposition in the body can be regulated by silencing the fat storage-inducing transmembrane (FIT) proteins. In our current study we have evaluated the abdominal and hepatic fat in both adipose-specific fat storage inducing transmembrane knockout (AFIT2KO) and their littermate (LL) control groups. Our results show that silencing of the AFIT2 protein specifically reduced the fat accumulation in adipose tissue whereas increased the fat accumulation in liver of AFIT2KO mice. Modulation (either down regulation or silencing) of these proteins might be of potential for drug discovery for obesity and type 2 diabetes

Lihong Jiang¹, Zejian Liu², Bei Wang¹, Greame Mason^1,3, Douglas Rothman¹, and Raimund Herzog^2
1Diagnostic Radiology, Yale University School of Medicine, New Haven, CT, United States, ²Internal Medicine, Yale University School of Medicine, New Haven, CT, United States, ³Psychiatry, Yale University School of Medicine, New Haven, CT, United States

Medium chain triglycerides (MCTs) have been used for treating food absorption disorders and digestive diseases, and have been shown increase glucose sensitivity in diabetic patients. We have investigated the metabolic adaptations in STZ-treated diabetic rats fed with a MCT-enriched diet, using in vivomagnetic resonance spectroscopy and metabolic modeling with infusions of [2,4- ¹³ C ₂]-hydroxyl-butyrate (BHB) under a hyperinsulinemic hypoglycemic clamp. We have found that MCT diet decreased BHB uptake in astrocytes and increased glucose oxidation in neurons. The results were confirmed with qPCR technique. Our results suggest that MCT diet may not help to increase brain energy supply under acute hypoglycemia without antecedent recurrent hypoglycemia.

Alessandra Bierwagen^1,2, Sofiya Gancheva^1,2, Chrysi Koliaki^1,2, Peter Nowotny^1,2, Jesper Lundbom^1,2, Martin Heni^3,4, Andreas Fritsche^3,4, Hans-Ulrich Häring^3,4, Julia Szendroedi^1,5, and Michael Roden^1,5
1Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University, Duesseldorf, Germany,²German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Duesseldorf, Germany, ³Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and, Eberhard Karls University, Tübingen, Germany, ⁴Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the Univer, Germany, ⁵Department of Endocrinology and Diabetology, University Hospital, Duesseldorf, Germany

This study investigates the acute effects of central insulin on hepatic ATP and Pi content in healthy humans. Eight lean humans (26±2 yrs, BMI 23±1 kg/m2) received intranasal insulin (INI), intravenous insulin (IVI) and placebo. ³¹P spectra of the human liver were acquired before and 3h after administration. The liver ATP concentration increased by 25.7 ± 23.5% 3h after INI (p = .02), while it remains constant after IVI and placebo. In conclusion, intranasal insulin application can improve hepatic energy metabolism in healthy humans.

Andrea Bianchi¹, Teresa Bluhmki¹, Tanja Schoenberger², Andrea Vögtle¹, David Kind¹, Eric Kaaru¹, Michael Neumaier¹, Birgit Stierstorfer², Thomas Kaulisch¹, and Detlef Stiller^1
1Targeting Discovery Research, In vivo imaging laboratory, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Baden-Württemberg, Germany, ²Targeting Discovery Research, Target Validation Technologies, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Baden-Württemberg, Germany

Colonoscopy, the current gold-standard for inflammatory bowel disease diagnostics and follow-up, is known to cause discomfort in patients. In addition, this technique doesn’t permit to detect extracolonic lesions, being restricted to the diagnostics of visible changes in the mucosal surface. We propose here an in vivo MRI longitudinal study of colon wall thickness as an imaging biomarker to detect and stage the severity of this disease in a mouse model of dextran sulfate sodium (DSS)-induced colitis. The results were validated against colonoscopy and standard ex vivo histology. The intra- and inter- operator reproducibility was assessed for all the measurements.

Peter S.N. van Rossum^1,2, Astrid L.H.M.W. van Lier¹, Marco van Vulpen¹, Onne Reerink¹, Steven H. Lin³, Richard van Hillegersberg², Jelle P. Ruurda², Gert J. Meijer¹, and Irene M. Lips^1
1Department of Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands, ²Department of Surgery, University Medical Center Utrecht, Utrecht, Netherlands, ³Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States

This study aimed to explore the value of diffusion-weighted magnetic resonance imaging (DW-MRI) for the prediction of response to neoadjuvant chemoradiotherapy (nCRT) in esophageal cancer. In 20 patients receiving nCRT for esophageal cancer DW-MRI scanning was performed before nCRT, after 8-13 fractions, and before surgery. The median tumor apparent diffusion coefficient (ADC) was determined at these three time points. The predictive potential of initial tumor ADC, and change in ADC (ΔADC) during and after treatment for pathologic complete response (pathCR) was assessed. The treatment-induced change in ADC during the first 2-3 weeks of nCRT (ΔADCduring) was highly predictive for pathCR.

Cecilia Besa¹, Stephen Ward², Yong Cui³, Guido Jajamovich⁴, Michelle Kim⁵, and Bachir Taouli^6
1Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ²Pathology, Icahn School of Medicine at Mount Sinai, NY, United States,³Radiology, Peking University Cancer Hospital & Beijing Cancer Hospital, Beijing, China, ⁴Icahn School of Medicine at Mount Sinai, NY, United States,⁵Surgery, Icahn School of Medicine at Mount Sinai, NY, United States, ⁶Icahn School of Medicine at Mount Sinai, New York, NY, United States

Synopsis: The purpose of this study was to evaluate the value of quantitative diffusion weighted imaging (DWI) and dynamic contrast enhanced (CE) MRI in predicting histopathologic characteristics of liver metastatic neuroendocrine tumors (NET). We found that neuroendocrine carcinoma (G3) liver metastases had significantly lower ADC values and higher arterial enhancement rate (ER) than Grade 1 and 2 NETs. In addition, significant negative correlation was observed between ADC and ER and mitotic count and Ki-67% labeling index. DWI with ADC quantification and CE-MRI may be useful for predicting tumor grade in metastatic hepatic NET.

Lianhua Huang¹, Yihao Guo², Yingjie Mei³, Lizhi Zhou⁴, Zeyu Zheng¹, Yanqiu Feng⁵, Xinying Wang⁶, Jie Feng¹, Chenggong Yan¹, and Yikai Xu^1
1Department of Medical Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China, ²School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China, ³Philips healthcare, Guangdong, China, ⁴Department of Biostatistics, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, Guangdong, China, ⁵Guangdong Provincial Key Laborary of Medical Image Processing, School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China, ⁶Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China

The purpose of this study was to test the inter-scan reproducibility of the IVIM model parameters in assessing small bowel disease. The patients with clinically or pathologically confirmed Crohn's disease underwent DW-MRI on a 3.0T MR scanner.Region growing method was used to draw the ROI of the whole disease bowel loop to obtain the IVIM model parameters(f, D*, D), and the coefficient of determination were calculated to correct the mean D, f and D* of the ROI. Then the parameters were compared between two different acquisitions by using the paired t test. Reproducibility of parameters were determined by using 95% Bland-Altman limits of agreement, repeatability coefficients and intraclass correlation coefficients (ICC). For this study population, there was good to moderate measurement reproducibility of D, and D* of small bowel CD.

Mary-Louise C Greer^1,2, Zehour Alsabban¹, Ryan Lo³, Rahim Moineddin⁴, Peter Church⁵, Thomas D Walters^3,5, Jacob C Langer^3,6, and Anne Griffiths^3,5
1Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada, ²Medical Imaging, University of Toronto, Toronto, Ontario, Canada,³University of Toronto, Ontario, Canada, ⁴Department of Family and Community Medicine, Dalla Lana School of Public Health University of Toronto, Ontario, Canada, ⁵Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, Ontario, Canada, ⁶Division of General Surgery, The Hospital for Sick Children, Ontario, Canada

Hypothesizing pelvic MRI in children is comparable in detecting perianal disease when performed at 1.5T and 3T, 133 pelvic MRI performed using standard perianal technique at 1.5T and/or 3T in 94 children with pediatric inflammatory bowel disease (PIBD) were retrospectively reviewed by two radiologists for perianal fistulae and abscesses. Similar frequencies, types and location of perianal disease were detected in both groups, validating imaging at either field strength. A secondary aim, describing frequency of perianal fistula types in PIBD using Parks’ criteria, demonstrated a different frequency of fistula type in children compared with adults, all either trans-sphincteric or inter-sphincteric.

Susan E Pritchard¹, Klara C Garsed², Caroline L Hoad¹, Melanie Lingaya³, R Banwait³, W Thongborisute³, E Roberts³, Carolyn Costigan^1,3, Luca Marciani^2,3, Robin C Spiller^2,3, and Penny A Gowland^1
1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, Notts, United Kingdom, ²Nottingham Digestive Diseases Biomedical Research Unit, Nottingham University Hospitals, Nottingham, Notts, United Kingdom, ³Nottingham Digestive Diseases Centre, School of Clinical Sciences, University of Nottingham, Nottingham, Notts, United Kingdom

Stress is known to affect oro-caecal transit in patients with irritable bowel syndrome with diarrhoea (IBS-D). This study evaluated the effect of a sensory (ice-cold versus warm water hand immersion) and a pharmaceutical stressor (corticotrophin releasing hormone (CRH) versus placebo) on postprandial fluid transport in the small and large bowel in two groups of healthy volunteers. Both stressors redistributed fluid in the intestine, similar to that previously seen in IBS-D, and CRH also increased the ascending colon volume. This was associated with increased sensations of distension and bloating. Similar mechanisms could account for symptoms reported in IBS patients.

Lin Qiu¹, Xiang-ran Cai¹, Si-run Liu¹, You-zhen Feng², and Chang-yu Guo^3
1Medical Imaging Center, the First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China, ²the First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China, ³Medical Imaging Center, Centro Hospitalar Conde de São Januário, Macau, Macau, China

IVIM sequence can reveal standard ADC, D, D* and f values of rectal carcinoma, which is useful for demonstrating the pathophysiology process of rectal cancer. The optimal images are shown in b=800~1000 s/mm2, but with the moderate accuracy in T-staging diagnosis

Zhengyang Zhou¹, Song Liu¹, Jian He¹, and Wenxian Guan^2
1Radiology, Affiliated Drum Tower Hospital,School of Medicine,Nanjing University, Nanjing, Jiangsu, China, ²Gastrointestinal Surgery, Affiliated Drum Tower Hospital,School of Medicine,Nanjing University, Nanjing, Jiangsu, China

Seventy patients with gastric cancer underwent preoperative diffusion-weighted MRI and then surgical resection. Mean and min ADC values of each gastric cancer were obtained. Postoperative TNM staging of each patient was determined. Mean and min ADC values of gastric cancers with different TNM staging were compared. Both mean and min ADC values of gastric cancers correlated with postoperative T staging and N staging. Both mean and min ADC values of gastric cancers correlated with the area and depth of the lesions. The preoperative ADC values of gastric cancers can provide valuable information to predict postoperative TNM staging of the patients.

Zhengyang Zhou¹, Song Liu¹, Jian He¹, and Wenxian Guan^2
1Radiology, Drum Tower Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu, China, ²Gastrointestinal Surgery, Drum Tower Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu, China

Sixty-nine patients with gastric cancer underwent preoperative diffusion-weighted MRI and surgical resection. Mean and min ADC values of each gastric cancer as well as normal gastric walls were obtained. Meanwhile, histologic type, differentiation degree and Lauren classification of each resected specimen were determined. There were significant differences of mean and min ADC values among gastric cancers with different histologic types, differentiation degrees and Lauren classifications. Mean and min ADC values correlated with histologic differentiation and Lauren classification significantly. We concluded the ADC values may be helpful in evaluating gastric cancers¡¯ histologic features, such as histologic types, differentiation degrees and Lauren.

cao xi sheng¹, chen yunbin^1,2, cai linfeng¹, wei wei¹, hu chunmiao¹, and chen weibo^3
1Radiology, Fujian Provincial Cancer Hospital, FUZHOU, FUJIAN, China, ²Fujian Medical University, FUJIAN, China, ³Philips Healthcare, shanghai, China

This paper is about the feasibility and preliminary experience of a Diffusional Kurtosis Model for detection rectal cancer.

Vlad Ceregan¹, Jelena Curcic^1,2, Sebastian Kozerke¹, and Andreas Steingoetter^1,2
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, ²Division of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland

The assessment of intragastric perfromance of therapeutic agents is of main importance for effective drug delivery design. This work takes a first step in this direction by proposing a MRI method for 4D monitoring of the release and distribution of a drug model from a standard hard gelatine capsule within the human stomach. The results show that accelerated 4D MRI is feasible in visualizing release and dispersion of an ingested drug model at temporal resolutions of up to 1 second.

Candice A. Bookwalter¹, Michael D. Repplinger^1,2, Perry J. Pickhardt¹, Jessica B. Robbins¹, Timothy J. Ziemlewicz¹, Douglas Kitchin^1,3, and Scott B. Reeder^1,4
1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²Department of Emergency Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States, ³St. Mary's Hospitals, Madison, Wisconsin, United States, ⁴Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, United States

Prospective contrast-enhanced MRI and MDCT evaluation of 165 patients presenting with non-traumatic acute abdominal pain was obtained. Two experienced radiologists reviewed all available clinical and imaging data to derive an image-based diagnosis. A total of 62/165 (38%) patients were diagnosed with relevant imaging findings other than acute appendicitis. Of these, 30/62 (48%) of patients were diagnosed with a non-appendiceal gastrointestinal abnormality, 31/62 (50%) with a genitourinary abnormality, and 1/62 (2%) with an extra-abdominal abnormality.

Jonathan F. Brand¹, Lars R. Furenlid^1,2, Maria I Altbach², Jean-Philippe Galons², Tulshi Bhattacharyya², Achuyt Bhattacharyya³, Ali Bilgin^2,4, Zhitao Li⁴, and Diego R. Martin^2
1College of Optical Sciences, University of Arizona, Tucson, AZ, United States, ²Department of Medical Imaging, University of Arizona, Tucson, AZ, United States, ³Department of Pathology, University of Arizona, Tucson, AZ, United States, ⁴Electrical and Computer Engineering, University of Arizona, Tucson, AZ, United States

The staging of hepatic fibrosis is critical to monitoring chronic liver disease progression. The current gold standard is liver biopsy which is invasive, has associated risks, and results are affected by sampling errors. The objective of this study is to use high resolution MRI to detect the textural change in the liver due to fibrosis and locally analyze the tissue with a mathematical observer to grade fibrosis on a scale consistent with the standard METAVIR score used in biopsy.