Suchandrima Banerjee¹, David Aramburu-Nunez², Ramesh Paudyal², Thomas Chenevert³, Michael Boss⁴, and Amita Shukla-Dave^2,5
1Global MR Applications & Workflow, GE Healthcare, Menlo Park, CA, United States, ²Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ³Department of Radiology, University of Michigan Health System, Ann Arbor, MI, United States, ⁴Applied Physics Division, National Institute of Standards and Technology, Boulder, CO, United States, ⁵Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States

The benefits of reduced field-of-view (rFOV) imaging with the single-shot echoplanar diffusion sequence such as lower distortion and better discrimination of tumor from benign tissue have been demonstrated in several anatomies. In most of these published works, lower ADC was reported using rFOV compared to the standard full FOV (fFOV) method, irrespective of the technique by which rFOV was achieved. In this work we conducted controlled experiments in 3 phantoms to avoid some of the confounding factors present in vivo and investigated if there is a systemic underestimation of ADC in rFOV DWI compared to fFOV DWI. 

Sona Saksena¹, Devon M Middleton², Laura Krisa³, Pallav Shah², Scott H Faro², Rebecca Sinko³, John Gaughan⁴, Jürgen Finsterbusch⁵, M J Mulcahey³, and Feroze B Mohamed^1
1Department of Radiology, Thomas Jefferson University, Philadelphia, PA, United States, ²Department of Radiology, Temple University, Philadelphia, PA, United States, ³Department of Occupational Therapy, Thomas Jefferson University, Philadelphia, PA, United States, ⁴Biostatistics Consulting Center, Temple University School of Medicine, Philadelphia, PA, United States, ⁵Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

This is the first study in pediatric subjects investigating the DTI values and it’s reproducibility along the entire cervical and thoracic spinal cord (SC). DTI data was acquired from 22 typically developing (TD) children and 15 patients with spinal cord injury (SCI) using an inner field-of-view DTI sequence. Regions of interest were manually drawn on whole cord at every axial slice along the cervical and thoracic SC. Fractional anisotropy and radial diffusivity values were significantly different between TD and SCI suggesting that these appear to be the most sensitive parameter in assessing the state of SC in chronic phase of SCI. This study demonstrates that DTI has a potential to be used as an imaging biomarker for evaluating the extent of injury, which may be useful to prognosticate as well as monitor patients with SCI

Olivier Reynaud¹, Jin Zhang¹, Kerryanne Veronica Winters¹, Dmitry Novikov¹, and Sungheon Gene Kim^1
1Center for Biomedical Imaging, Department of Radiology, NYU School of Medicine, New York, NY, United States

In this study, we investigate the feasibility of using the recently proposed diffusion MRI method, POMACE (Pulsed and Oscillating gradient MRI Assessment of Cell size and Extracellular space) for characterization of tissue changes induced by chemotherapy. Surface-to-volume ratio (S/V), cell size (R_cell) and extracellular space volume fraction (ECS) are estimated prior to and after 5FU and bevacizumab treatment in GL261 murine glioma model. Preliminary results indicate an early ECS decrease two days after 5FU/bevacizumab administration. By combining OGSE and PGSE, POMACE provides non-invasive and quantitative metrics regarding tumor microstructure that can be applied to evaluate treatment response.

Rajakumar Nagarajan¹, Manoj K Sarma¹, Edward Xu¹, Paul M Macey², Mario Guerrero ³, Vanessa Correa ³, Eric S Daar³, and M.Albert Thomas^1
1Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States, ²UCLA School of Nursing, University of California at Los Angeles, Los Angeles, CA, United States, ³Department of Medicine, Harbor-UCLA Medical Center, Torrance, CA, United States

Our current study examined whether neuroimaging abnormalities in HIV infected adults are associated with neuropsychological changes as measured by diffusion tensor imaging (DTI) and HIV Dementia scale (HDS). Several brain regions demonstrated significantly decreased values of fractional anisotropy and mean diffusivity. Also there was a significant decline of HDS scores observed in the construction abilities of HIV infected adults compared to healthy controls. This study indicates that DTI is a sensitive tool for correlating neuroanatomic pathologic features with specific cognitive deficits in patients with HIV infection.

Chun-Xia Li¹, Yumei Yan¹, Frank Tong², Doty Kempf¹, Stuart Zola^1,3,4, Leonard Howell^1,3, and Xiaodong Zhang ^1
1Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States, ²Department of Radiology, School of Medicine, Emory University, Atlanta, GA, United States, ³Department of Psychiatry and Behavioral Sciences, School of Medicine, Emory University, Atlanta, GA, United States, ⁴Atlanta Veterans Affairs Medical Center, Decatur, GA, United States

In the present study, adult macaque monkeys were utilized to characterize the temporal changes of DTI-derived diffusion indices in grey matter (GM) and white matter (WM) after ischemic stroke. Our reults showed that mean diffusivity (MD), radial diffusivity (RD) and axial Diffusivity (AD)  decreased significantly in GM and WM  immediately post stroke while fractional anisotropy (FA) remained unchanged until 48-hour post stroke.  The results demonstrate the sensitivity and robustness of MD, AD and RD to access the ischemic injury of GM and WM during hyperacute stroke, and also reveal the temporal evolutiom of the WM and GM microstructure following stroke onset.

Jakob Weiss¹, Jana Taron¹, Ahmed E. Othman¹, Petros Martirosian¹, Sascha Kaufmann¹, Ulrich Kramer¹, Konstantin Nikolaou¹, and Mike Notohamiprodjo^1
1Diagnostic and Interventional Radiology, University of Tuebingen, Tuebingen, Germany

To evaluate the clinical performance of simultaneous multi-slice (sms) diffusion-weighted imaging (DWI) of the prostate. A prototype sms-DWI sequence was utilized and compared to conventional DWI sequences. Sms acquisition is based on the recently introduced principle of simultaneously exciting and acquiring multiple slices by a single radiofrequency (RF) pulse, thus accelerating image acquisition directly by the number of simultaneously excited slices (MB-factor). Image analyses revealed similar image quality and lesion detection as compared to conventional DWI sequences at a substantially decreased acquisition time. Sms-DWI seems a valuable alternative to conventional DWI sequences for prostate imaging.

Oliver J. Gurney-Champion^1,2, Remy Klaassen³, Martijn Froeling^1,4, Jaap Stoker¹, Johanna W. Wilmink^3,5, Arjan Bel², Hanneke W.M. van Laarhoven³, and Aart J. Nederveen^1
1Radiology, Academic Medical Center, Amsterdam, Netherlands, ²Radiation Oncology, Academic Medical Center, Amsterdam, Netherlands, ³Medical Oncology, Academic Medical Center, Amsterdam, Netherlands,⁴Radiology, University Medical Center Utrecht, Utrecht, Netherlands, ⁵Internal Medicine, Academic Medical Center, Amsterdam, Netherlands

We compare the performance of six models for diffusion weighted MRI (DWI) data signal intensity as a function of b-values. We obtained three DWI-datasets spread over two sessions from 9 pancreatic cancer patients. To characterize the fit parameters’ sensitivity to abnormalities, we compared the difference in fit parameter values between tumorous and healthy tissue. To characterize repeatability, we obtained the coefficient of variation. Every model had exactly one parameter that was significantly sensitive to tumorous tissue (p<0.05). From these parameters, the most sensitive parameter was f₂ from the tri-exponential model, whereas the best repeatable measure was the ADC from the mono-exponential model.

Clare B Poynton¹, Marsha Lee², Yi Li¹, Zoltan Laszik³, John D Mackenzie¹, Pauline W Worters⁴, and Jesse Courtier^1
1Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, ²Department of Pediatrics, University of California, San Francisco, San Francisco, CA, United States, ³Department of Pathology, University of California, San Francisco, San Francisco, CA, United States, ⁴GE Healthcare, Menlo Park, CA, United States

This study investigated the use of intravoxel incoherent motion (IVIM) analysis for characterizing diffusion in renal allografts of pediatric transplant recipients.  Patients were separated into two groups according to whether or not a renal allograft biopsy resulted in a change in clinical management. Patients requiring a change in management (i.e., increase in immunosuppression) showed statistically significant differences in tissue diffusivity in the region of the biopsy relative to those that did not require any change. These results suggest IVIM analysis may be a useful non-invasive tool for guiding clinical management of pediatric kidney transplant patients.

Martin Cousineau¹, Eleftherios Garyfallidis¹, Marc-Alexandre Côté¹, Pierre-Marc Jodoin¹, and Maxime Descoteaux^1
1Computer Science, Université de Sherbrooke, Sherbrooke, QC, Canada

Tractometry is a hot topic in population analysis that combines diffusion MRI metrics along white matter bundles. Using a dataset of 11 healthy subjects with 3 different acquisitions collected within the same week, and a state of the art processing pipeline that removes outliers and splits bundles in separate parts by computing their centroid, we perform a test-retest study which validates that tractometry results are reproducible in terms of shape, volume, average metric value, and tract profiles.

Timo Roine¹, Ben Jeurissen¹, Daniele Perrone², Jan Aelterman², Wilfried Philips², Jan Sijbers¹, and Alexander Leemans^3
1iMinds-Vision Lab, Department of Physics, University of Antwerp, Wilrijk (Antwerp), Belgium, ²Ghent University-iMinds/Image Processing and Interpretation, Ghent, Belgium, ³Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands

We studied the reproducibility of whole-brain structural brain connectivity networks reconstructed with constrained spherical deconvolution based probabilistic fiber tractography. Our main finding is that a low spherical harmonics order decreases the reproducibility of graph measures in connectomics. This is most likely caused by the wider peaks in the fiber orientation distributions, which increase the variation in orientations sampled by the tractography algorithm. Based on our observations, we recommend using spherical harmonics decomposition with an order of at least eight whenever the data allows so. In addition, threshold value was important for binary networks, and some network properties were highly intercorrelated.

Irene Marco-Rius¹, Jeremy A Gordon¹, Peder EZ Larson¹, Romelyn delos Santos¹, Robert A Bok¹, Aras Mattis^2,3, Jacquelyn Maher^3,4, Daniel B Vigneron^1,3, and Michael A Ohliger^1,3
1Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States, ²Department of Pathology, University of California San Francisco, San Francisco, CA, United States, ³Liver Center, University of California, San Francisco, San Francisco, CA, United States, ⁴Department of Medicine, Division of Gastroenterology, University of California San Francisco, San Francisco, CA, United States

Diffusion weighted MRI has been widely used to measure the movement of water molecules and study tissue microstructure in order to characterize both diffuse and focal liver disease. In liver fibrosis, for instance, increased collagen formation is associated with restricted diffusion of water. However, the majority of water within the liver is either in the vascular or intracellular space, making the diffusion of water a potentially poor marker for fibrosis, which is an extracellular process. Here, we investigated applying diffusion-weighted MRI with an exogenously injected extracellular agent, hyperpolarized ¹³C-urea, as a potentially more sensitive probe of the extracellular space in the liver in a mouse model of liver fibrosis induced with CCl₄. 

Oliver J. Gurney-Champion^1,2, René van der Bel³, Martijn Froeling^1,4, C.T. Paul Krediet³, and Aart J. Nederveen^1
1Radiology, Academic Medical Center, Amsterdam, Netherlands, ²Radiation Oncology, Academic Medical Center, Amsterdam, Netherlands, ³Internal Medicine, Academic Medical Center, Amsterdam, Netherlands,⁴Radiology, University Medical Center Utrecht, Utrecht, Netherlands

In this study, we show the potential of the tri-exponential intravoxel incoherent motion (IVIM) model parameters as surrogates for kidney function. We show (n=8) that f₁, f₂ and D (fit parameters) changed as function of angiotensin-II dose (0, 0.3, 0.9 and 3 ng/kg/min). The changes in f₁ and f₂ correlated (correlation coefficient r=0.42 and -0.62; p=0.01 and p<0.001) to changes in effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) deduced from a ¹²⁵I-thalamate and ¹³¹I-hippuran clearing test. Finally, we showed (n=6) high inter-session and intra-session repeatability with coefficients of variation below 15% for all fit parameters.

Hugh Harvey¹, Jeremie Fromageau², Veronica Morgan¹, Liz Bancroft³, Ros Eeles³, Jeff Bamber², and Nandita deSouza^1
1Radiotherapy & Imaging, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom, ²The Institute of Cancer Research, London, United Kingdom, ³Oncogenetics, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom

Location-matched ROI analysis of tissue stiffness (SWE) and water diffusivity (ADC) in 9 normal prostates demonstrated that both techniques can adequately differentiate between peripheral and transitional zonal microenvironments, and that there is a weak negative correlation between tissue stiffness and water diffusivity in the peripheral zone. This suggests that factors such as microvascularity, cell size, extracellular matrix and macromolecules may have a differential effect on tissue stiffness and diffusivity. Transitional zone stiffness is too heterogeneous to demonstrate significant inter-modality correlation.

Xiaopeng Zhou¹, Ken Sakaie¹, Josef Debbins², Robert Fox¹, and Mark Lowe^1
1Cleveland Clinic, Cleveland, OH, United States, ²Barrow Neurological Institute, Phoenix, AZ, United States

The dependence of DTI metrics on SNR was investigated in a longitudinal multicenter clinical trial. We presented a combined simulation and experimental analysis of the effect of SNR on DTI measures using 27 scanners over 15 months.  Although the dependence of DTI measures on SNR is different for each type of scanner, we demonstrate the inverse relation between mean diffusivity and SNR and FA decreasing slightly with SNR. A sufficient SNR is essential for a reliable estimation of DTI parameters generally and the dependence of DTI measures on SNR should be accounted for or corrected when comparing results among scanners.

Xiaopei Xu¹, Henry KF Mak¹, Raja Rizal Azman², Kui-Kai Lau³, and Edward S Hui^1
1Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong, Hong Kong, ²Department of Bio-Medical Imaging, University of Malaya, Kuala, Malaysia, ³Department of Medicine, The University of Hong Kong, Hong Kong, Hong Kong

To explore the influences of brain microbleeds (BMBs) on structural brain network in stroke patients, we used DTI-based tractography and brain network analysis to investigate the brain structural network configuration in stroke patients with and without BMBs. Our results demonstrated disrupted balance between integrated and segregated process in global network, and enhanced specialized functions in stroke patients with BMBs. These findings suggested that the presence of BMBs is related to a disturbed brain network organization with imbalanced integrated and segregated information process ability, and brain network analysis is a sensitive tool to assess the impaired cognition caused by cerebral small vessel disease.

Junyu Guo¹, John O. Glass¹, JungWon Hyun¹, Yimei Li¹, Conklin Heather¹, Lisa Jacola¹, Ching-Hon Pui¹, Sima Jeha¹, and Wilbrun E. Reddick^1
1St Jude Children's Research Hospital, Memphis, TN, United States

We investigate the relationship of structural diffusion tensor imaging (DTI) metrics with working memory and decision speed performance in children treated for acute lymphoblastic leukemia (ALL). We built a core neurocognitive network including a central executive network, a salience network, and subcortical cortex based on previous fMRI findings. We generated structural connectivity pathways based on high-resolution DTI data from the human connectome project, and applied those in ALL patients to quantify DTI measures in each pathway.  We found that DTI measures in most  pathways were significantly associated with working memory and decision speed performance suggesting an essential structural neurocognitive network.

Man Sun¹, Hongyan Ni², Xu Yan³, and Tianyi Qian^4
1First Central Clinical College, Tianjin Medical University, Tianjin, China, People's Republic of, ²Tianjin First Central Hospital, Tianjin, China, People's Republic of, ³MR Collaborations NE Asia, Siemens Healthcare, Shanghai, China, People's Republic of, ⁴MR Collaborations NE Asia, Siemens Healthcare, Beijing, China, People's Republic of

Applying simultaneous-multi-slice EPI (SMS EPI) sequences in diffusion-weighted imaging (DWI) can reduce scanning time greatly, but its clinical-routine image quality in different body parts has not been broadly tested. This study compared multi-site DWI images acquired with a prototype SMS EPI sequence with those acquired with a traditional EPI sequence, computed SNR and CNR and conducted paired t-test. The results show there are no significant differences of SNR and CNR between the two kinds of sequence (p>0.05). When the SMS EPI sequence was applied to the clinical DWI examination, it not only reduced scanning time, but also kept the SNR, CNR in the same level as standard EPI. The SMS sequence was able to satisfy the requirements of clinical disease diagnosis.

Yu-Chun Lo¹, Yu-Jen Chen¹, Yung-Chin Hsu¹, Susan Shur-Fen Gau², and Wen-Yih Isaac Tseng^1
1Institute of Medical Device and Imaging, National Taiwan University College of Medicine, Taipei, Taiwan, ²Department of Psychiatry, National Taiwan University College of Medicine, Taipei, Taiwan

Impaired social communication skills have been consistently reported in autism spectrum disorder (ASD). We used diffusion spectrum imaging to measure white matter integrity of the social communication network, and investigated its relationships with social communication and social interaction in 62 ASD and 55 typically developing (TD) boys. ASD showed partially reduced white matter integrity of the social communication network as compared to TD. Positive correlations were found between white matter integrity and the social interaction in ASD. In conclusion, altered microstructural property of the social communication network might be a structural correlate of social communication deficits in ASD.

Wei-Cheng Lee¹, Sheng-Min Huang ¹, Cheng-He Li¹, Kung-Chu Ho², and Fu-Nien Wang^1
1Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan, ²Nuclear Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan

The well-behaved residual of a successful fitting model should present as an independent random variable in its histogram, otherwise it will contain structure that is not accounted for in this model. In the study, we found that there are two groups of fitting residuals. And the spatial mapping of these smaller negative pixels reveals that the overestimation of kurtosis model is related to the contribution of vessel signal. Therefore, we proposed a semi-kurtosis model to calculate the restricted diffusion adequately and obtain correct DKI information in these regions with vascular interference.

Ralf Lützkendorf¹, Robin M. Heidemann², Thorsten Feiweier², Michael Luchtmann³, Sebastian Baecke¹, Joern Kaufmann⁴, Joerg Stadler⁵, Eike Budinger⁵, and Johannes Bernarding^1
1Biometry and Medical Informatics, University of Magdeburg, Magdeburg, Germany, ²Siemens Healthcare GmbH, Erlangen, Germany, ³Department of Neurosurgery, University of Magdeburg, Magdeburg, Germany, ⁴Department of Neurology, University of Magdeburg, Magdeburg, Germany, ⁵Leibniz Institute for Neurobiology, Magdeburg, Germany

Diffusion anisotropy in cortical gray matter (GM) and adjacent white matter (WM) provides microanatomic information about the course of the neuronal structures within GM and when connecting to other brain regions. However, interwoven neuronal fiber orientations and complex folded structures render the analysis difficult. Ultra-high-field diffusion MR imaging (dMRI) overcomes these limitations as the improved SNR allowed acquiring 1.4 mm isotropic voxel with increased diffusion-weighting. Applying constrained spherical deconvolution (1) enabled resolving radial and tangential anisotropic diffusion in cortical gray matter confirming recent reports of reduced radial anisotropy in primary somatosensory cortex as compared to other cortical areas (2).

Mami Iima^1,2, Tomomi Nobashi¹, Hirohiko Imai³, Sho Koyasu¹, Akira Yamamoto¹, Yuji Nakamoto¹, Masako Kataoka¹, Tetsuya Matsuda³, and Kaori Togashi^1
1Department of Diagnostic Imaging and Nuclear Medicine, Graduate Schoolof Medicine, Kyoto University, Kyoto, Japan, ²The Hakubi Center for Advancer Research, Kyoto University, Kyoto, Japan, ³Department of Systems Science, Graduate Schoolof of Informatics, Kyoto University, Kyoto, Japan

The relationship between diffusion time and diffusion parameters in a human hepatocellular carcinoma xenograft mouse model was investigated at 7T. There was an increase in K values and decrease in ADCo values in 27.6ms compared to 9.6 ms. Accordiginly a remarkable difference in a composite index (sADC) was also found. The investigation of the water diffusion behavior at different diffusion times may provide valuable information on the contribution of the different compartments or tissue components to the overall diffusion MRI.

Hsien-Te Su¹, Tzu-Hsun Tsai², Yao-Chia Shih³, Yu-Shiang Tzeng⁴, Chien-Chung Chen⁴, and Wen-Yih Isaac Tseng^1,5
1Institute of Medical Device and Imaging, National Taiwan University College of Medicine, Taipei City, Taiwan, ²Department of ophthalmology, National Taiwan University Hospital, Taipei City, Taiwan, ³Institute of Biomedical Engineering,National Taiwan University, Taipei City, Taiwan, ⁴Department of Psychology, National Taiwan University College of Science, Taipei City, Taiwan, ⁵Molecular Imaging Center, National Taiwan University, Taipei City, Taiwan

To investigate whether the white matter tracts are altered in patients with strabismus, we used diffusion spectrum imaging to measure microstructural property of 78 major white matter tracts, and compared the property between 12 patients with strabismus adults and 24 matched controls. As compared to the controls, patients showed differences with large effect sizes in the left vertical occipital fasciculus, callosal fibers to bilateral precuneus, callosal fibers to bilateral inferior parietal lobules, and the left superior longitudinal fasciculus I. The altered white matter tracts support the hypothesis of underlying microstructural changes of the visual pathways in strabismus.

Wei Liu¹ and Kun Zhou^1
1Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, China, People's Republic of

In this study, an automatic optimization scheme was proposed in diffusion-weighted imaging using simultaneous multi-slice (SMS) acceleration to determine an appropriate flip angle based on a short TR, which is capable to obtain similar contrast of a pair of tissue type compared to the one with long TR scan. With this optimization scheme, minimal TR in SMS case is practically achievable and there is no obvious contrast deviation between images from long TR (FA = 90⁰) and short TR (FA < 90⁰).

Changyu SUN¹, Lihui WANG², Feng YANG³, and Yuemin ZHU^1
1CREATIS; CNRS UMR 5220; Inserm U 1044; INSA of Lyon; University of Lyon;, Lyon, France, ²School of computer science and technology, Guizhou University, Guiyang, China, People's Republic of, ³School of Computer and Information Technology, Beijing JiaoTong University, Beijing, China, People's Republic of

Fiber crossing in the myocardium of the heart is controversial despite some reports on the heart of animals. The purpose of this study is to investigate the fiber configuration complexity in a voxel, such as fiber crossing, in the human heart. We applied two different reconstruction techniques commonly used in high angular resolution diffusion imaging (HARDI) to conventional diffusion tensor imaging (DTI) data of the human heart acquired on clinical MRI system. The results consistently demonstrated that the human myocardium exhibits some complex fiber configurations such as fiber crossing in a voxel.

Makoto Suzuki¹, Tatsuya Kuramoto¹, Yuki Hachiman¹, Yu Nishina², Satoru Morita², Kayoko Abe², and Masami Yoneyama^3
1Department of radiological servece, Tokyo Women's Medical University Hospital, Tokyo, Japan, ²Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women's Medical University Hospital, Tokyo, Japan, ³IS Business Group, Philips electronics japan, Tokyo, Japan

Direct-coronal diffusion-weighted whole body imaging with background body signal suppression using single-shot turbo spin-echo (TSE-DWIBS) with b-values of 400, 600, 800, and 1000 mm2/s, and DWIBS using echo-planner imaging (EPI-DWIBS) with b-value of 1000mm2/s  were obtained using 3T MR scanner in 5 healthy volunteers. We investigated optimal b-value of TSE-DWIBS and compared image distortions, contrast, signal-to-noise ratio (SNR), and artifacts between TSE-DWIBS and EPI-DWIBS. Image contrast and SNR of TSE-DWIBS with b-value of 800 mm2/s were equivalent to those of EPI-DWIBS with b-value of 1000 mm2/s. TSE-DWIBS had less image distortions and artifacts than EPI-DWIBS. Direct-coronal TSE-DWIBS using 3T MRI can be applied for clinical cases.

Mami Iima^1,2, Masako Kataoka¹, Shotaro Kanao¹, Natsuko Onishi¹, Makiko Kawai¹, Akane Ohashi¹, Rena Sakaguchi¹, and Kaori Togashi^1
1Department of Diagnostic Imaging and Nuclear Medicine, Graduate Schoolof Medicine, Kyoto University, Kyoto, Japan, ²The Hakubi Center for Advancer Research, Kyoto University, Kyoto, Japan

The effects of different numbers of b values and excitations on the non-Gaussian DWI parameter estimates in the breast of normal volunteers was assessed. A good agreement of Do, K and synthetic ADC200-1500 was observed among different number of b values as well as excitations. Lower Do and sADC200-1500 were found in women with lactation period. Higher K and fIVIM were observed in lactating volunteers with some overlap. A limited protocol using only 5 b values could be relevant in clinical setting, resulting in a remarkable reduction in acquisition time.

Yong-Lan He¹, Philipp Riffel², Daniel Hausmann², Stefan Schönberg², and Ulrike Attenberger^2
1Radiology, Peking Union Medical College Hospital, Beijing, China, People's Republic of, ²Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany

This is the first MR study to evaluate the use of zoomed EPI technology for diffusion-weighted imaging in the kidney. Zoomed diffusion-weighted EPI leads to substantial image quality improvements with reduction of susceptibility artifacts in renal DWI.  The combination of the two sequences for renal imaging might be recommended: a c-EPI scan to cover and screen the whole upper abdomen and a z-EPI scan focused on the targeted anatomical structure and suspected lesions. 

Elisenda Bonet-Carne¹, Alessandro Daducci^2,3, Eleftheria Panagiotaki¹, Edward Johnston⁴, Nicola Stevens⁴, David Atkinson⁴, Shonit Punwani⁴, and Daniel C Alexander^1
1Centre for Medical Image Computing, University College London, London, United Kingdom, ²Signal Processing Lab (LTS5), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, ³University Hospital Center (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, ⁴Centre for Medical Imaging, University College London, London, United Kingdom

The aim of this study is to extend the AMICO framework to the VERDICT model-based diffusion-weighted MRI (DW-MRI) technique and to evaluate its performance to prostate cancer imaging. DW-MRI was acquired for 4 subjects and the VERDICT model was fitted to the data using both fitting procedures. In both cases similar differences in parameter values between tumour and normal tissue were found. The AMICO formulation reduces the computation time for VERDICT and produces parameter maps that are more homogeneous than those obtained with the original fitting. The AMICO formulation reflects the microstructural differences in a clinically practical time.

Yung-Chieh Chang¹, Mu-Ch Chung², Kuo-Hsiung Shu², Hao-Chung Ho³, Yen-Chieh Ouyang⁴, Jyh-Wen Chai¹, and ClaytonChi-Chang Chen^1
1Department of Radiology, Taichung Veterans General Hospital, Taiwan, Taiwan, Taiwan, ²Division of Nephrology, Taichung Veterans General Hospital, Taiwan, Taiwan, Taiwan, ³Division of Urolog, Taichung Veterans General Hospital, Taiwan, Taiwan, Taiwan, ⁴Department of Electrical Engineering, National Chung Hsing University, Taiwan, Taiwan

The goal of the present study was to perform IVIM-DWI and non-contrast MRA of graft kidneys to evaluate the micro- and micro-structural status in 17 patients within 48 hours after transplantation. Five of them had a second scan in six months later.  The experimental results suggested that D*, D and f values in IVIM-DWI might considerably be useful in early detection of functional change graft kidneys and non-contrast MRA and PC-MRI could effectively assess patency and flow rates of graft vessels. Combination of both IVIM-DWI and non-contrast MRA would be potentially promising in clinical application for monitoring graft kidneys.

Kaining Shi¹, Ying Liu², Yu Shi², and Qiyong Guo^2
1Imaging Systems Clinical Science, Philips Healthcare, Beijing, China, People's Republic of, ²Radiology department, Shengjing Hospital of China Medical University, Shenyang, China, People's Republic of

Fussy clustering technique (FCM) has been combined with IVIM to increase the stability and reduce the post-processing time of the nonlinear curve fitting in IVIM. Another problem of the widely used bi-exponential IVIM model is its poor repeatability. This work is to assess the repeatability of IVIM with FCM between two scans in healthy liver by calculating the coefficient of variation and the 95% Bland–Altman limits of agreements. Results proved that FCM could improve the repeatability of IVIM, especially for the parameter D*, which was the most unstable among total 3 parameters.

Chen lihua¹, Liu ailian¹, Song qingwei¹, wang heqing¹, sun meiyu¹, Li ye¹, Chen ailian¹, and Zheng dandan^2
1The Affiliated Hospital of Dalian Medical University, Dalian, China, Dalian, China, People's Republic of, ²GE Healthcare, MR Research China, Beijing, Beijing, China, People's Republic of

Prostate cancer is the second most common cancer for men, and it has high leading cause of cancer death among men. In this study, DKI and DWI MR measurements were performed to investigate the correlation of the MK, Ka, Kr, MD, Da, Dr, FA and ADC values in ROIs of the prostate and benign prostatic hyperplasia. DKI working at present scanning hardware are capable to detect the pathophysiological changes unattainable to conventional MRI techniques. 

Harri Merisaari¹, Parisa Movahedi¹, Ileana Montoya¹, Jussi Toivonen¹, Marko Pesola¹, Pekka Taimen², Peter Boström², Tapio Pahikkala¹, Hannu Juhani Aronen¹, and Ivan Jambor^1
1University of Turku, Turku, Finland, ²Turku University Hospital, Turku, Finland

Eighty-one patients with historically confirmed PCa underwent two repeated 3T DWI examinations performed using 14 b-values in the range of 0-500 s/mm² and diffusion time of 19.004 ms. Various fitting methods for IVIM and mathematical models were evaluated in the terms of fitting quality (Akaike information criteria), repeatability, and Gleason score prediction. Monoexponential model demonstrated the highest repeatability and clinical values in the regions-of-interest based analysis of PCa DWI, b-values in the range of 0-500 s/mm².

Kun Sun¹, Xu Yan², and Fuhua Yan^1
1Department of Radiology, Ruijin Hospital,Shanghai Jiao Tong University School of Medicine, Shanghai, China, People's Republic of, ²Application Dept, Siemens Healthcare, Shanghai, China, People's Republic of

DKI model may provide additional information and improve the characterizing of breast lesions compared with conventional diffusion parameters. The kurtosis and water molecular diffusion heterogeneity index derived from DKI and stretched Exponential DWI may be helpful for the preoperative differentiation of proliferative activity of breast cancer.

Ivan I. Maximov¹, Aram Tonoyan², Daniel Edelhoff¹, Igor Pronin², and Dieter Suter^1
1TU Dortmund University, Dortmund, Germany, ²Burdenko Neurosurgery Institute, Moscow, Russian Federation

Diffusion weighted imaging is very powerful technique allows one to diagnose and differentiate glioma malignancy in vivo. Recently, the non-Gaussian diffusion models exhibited their efficacy in a detection of microsctructure changes for low and high grade gliomas. In this study we perform a comparative analysis of four diffusion models (DTI, DKI, two- and three-compartment models) in ability to provide a quantitative measure of the gliomas malignancy in vivo.

Yu Nishina¹, Satoru Morita¹, Tatsuya Kuramoto², Makoto Suzuki², Hitoshi Tadenuma², Yasuhiro Goto², Masami Yoneyama³, and Shuji Sakai^1
1Diagnostic Imaging and Nuclear Medicine, Tokyo Women's Medical University Hospital, Tokyo, Japan, ²Radiological Service, Tokyo Women's Medical University Hospital, Tokyo, Japan, ³Philips Electronics Japan, Tokyo, Japan

We compared the image quality of single-shot turbo spin-echo diffusion-weighted imaging (TSE-DWI) with parallel imaging and conventional echo planar DWI (EPI-DWI) in the pancreas of healthy volunteers. TSE-DWI with a sensitivity encoding factor (SF) of 2, 4, 6, and EPI-DWI with SF2 (b-values = 0, 500, 1000 s/mm2) were obtained using a 3T MRI scanner. Two radiologists evaluated overall image quality, susceptibility artifacts, and aliasing artifacts. TSE-DWI with moderate SF had better image quality than conventional EPI-DWI for a medium b-value because of less susceptibility artifacts.

Wieke Haakma^1,2,3, Jeroen Hendrikse¹, Anneriet M. Heemskerk⁴, Peter R. Luijten¹, Michael Pedersen³, Alexander Leemans⁴, and Martijn Froeling^1
1Radiology, University Medical Center Utrecht, Utrecht, Netherlands, ²Forensic Medicine, Aarhus University, Aarhus, Denmark, ³Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark, ⁴Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands

In this work we present our results obtained at the 7T MRI scanner investigating the nerves in the forearm. We tested two DTI protocols and were able to visualize the median, ulnar and radial nerves with fiber tractography with resolution up to 0.75×0.75×2.0 mm³. We have demonstrated the potential of 7T to identify these nerves and quantify their diffusion characteristics in a reliable way. We expect that the use of high resolution DTI can be beneficial in the investigation of peripheral nervous tissue in the forearm and might aid in identifying changes due to pathology. 

Fabian Hilbert¹, Tobias Wech¹, Henning Neubauer¹, Simon Veldhoen¹, Thorsten Alexander Bley¹, and Herbert Köstler^1
1Department of Diagnostic and Interventional Radiology, University of Würzburg, Würzburg, Germany

Echo-planar imaging (EPI) is usually applied to acquire diffusion-weighted images. While EPI is fast in acquiring an entire image, it brings along distortion artifacts. Turbo spin echo (TSE) acquisitions require more time than EPI, but avoid distortions. Purpose of this study was to compare TSE and EPI for diffusion tensor imaging of the human kidney. We found similar mean diffusivity with EPI and TSE. Fractional anisotropy provides good corticomedullary contrast with both methods TSE and EPI. TSE is a practicable alternative to EPI for diffusion tensor imaging of the kidney.

rammohan sai venkata vadapalli¹, Raghav dutt sai venkata Mulukutla², and abhinav sriiram Vadapalli^3
1Imaging, Vijaya diagnostics and research, Hyderabad 500020, India, ²Orthopaedic and Spine surgery, Udai orthopaedic Institute, Hyderabad 500020, India, ³Imaging, GH, Hyderabad 500020, India

Surgeons want to know Predictive disc health proximal to the level of fusion or intervention. Conventional MR imaging using T2 weighted Imaging is insensitive to early morphological changes with no predictive quantitative biomarker profile of early degeneration. The Thompson scale or the Pfirrmann scale are discontinuous scales fail to demonstrate the Degeneration or regeneration of disc Objectively. Multiparametric Imaging using T2 relaxometry maps,DTI indices namely FA and qualitative FA maps offer both quantitative and qualitative biomarkers for predictive disc health

Qi Yong Ai¹, Ann D. King¹, Benjamin King Hong Law¹, Lok Yiu Sheila Wong¹, Kunwar S. Bhatia¹, David Ka Wai Yeung², and Brigette B.Y. Ma^2
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, Hong Kong, ²Department of Clinical Oncology, The Chinese University of Hong Kong, Shatin, Hong Kong

This study evaluated pre-treatment diffusion weighted imaging of primary nasopharyngeal carcinoma for the prediction of patients at risk of distant metastases, based on long-term follow-up for at least 5 years. Analysis was performed of ADC parameters using histogram analysis (ADC_mean, ADC_skewness and ADC_kurtosis), together with stage and volume of the primary tumour and nodes. Multivariate analysis showed pre-treatment ADCskewness, T stage and nodal volume were significant ( p =0.026, 0.022 and 0.005, respectively), distant metastases being more likely in patients with tumours with ADC values skewed toward the higher ADC range, and higher T stage and nodal volume.

Xiaohang Liu¹, Liangping Zhou¹, Weijun Peng¹, and Yong Zhang^2
1Radiology, Fudan university shanghai cancer center, Shanghai, China, People's Republic of, ²MR Research China, GE healthcare, Beijing, China, People's Republic of

The diffusion weighted imaging (DWI) is commonly used in the diagnosis of Prostate cancer, but the cancer in Central gland (CG) is considered harder to detected on conventional DWI,but histogram analysis of apparent diffusion coefficient could potentially improve the differentiation of prostate cancer in CG. 

Oi Lei Wong¹, Jing Yuan¹, Gladys Goh Lo², Thomas W. T. Leung³, Wai Ki Chung², and Benny W. H. Ho^2
1Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, Hong Kong, ²Department of diagnostic & interventional radiology, Hong Kong Sanatorium & Hospital, Hong Kong, Hong Kong, ³Comprehensive Oncology Center, Hong Kong Sanatorium & Hospital, Hong Kong, Hong Kong

The use of IVIM in assessing the microcapillary perfusion and true diffusion has attracted elevating attention. The segmented bi-exponential fitting has been widely adopted to calculate IVIM metrics, in which a cut-off b-value is pre-defined for perfusion and diffusion region separation. This study calculated the corrected Akaike Information Criterion (AICc) for bi-exponential IVIM model in the healthy human liver with varying cut-off b-values and then compared to the AICc for the mono-exponential model. The statistical preference of the bi-exponential model to mono-exponential model was demonstrated based on the lowest AICc. This bi-exponential model preference was independent of the choice of cut-off b-value and ROI location.

Yoshihiko Fukukura¹, Toshikazu Shindo¹, Yuichi Kumagae¹, Koji Takumi¹, Hiroto Hakamada¹, Masanori Nakajo¹, and Takashi Yoshiura^1
1Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan

This study focused on the potential of ADC histogram analysis on DW imaging to characterize solid pancreatic masses. Among the ADC histogram parameters, the entropy of ADC with every b-value combination showed the highest area under the receiver operating characteristic curve for distinguishing neuroendocrine tumors from pancreatic adenocarcinomas and mass-forming autoimmune pancreatitis. The entropy of ADC might add helpful information in differentiating neuroendocrine tumors from pancreatic adenocarcinomas and mass-forming autoimmune pancreatitis, especially in patients with contraindication to contrast agents or with solid pancreatic masses showing atypical findings at dynamic CT or MRI.

Mariko Doai¹, Naoko Tsuchiya¹, Hisao Tonami¹, and Katsuo Usuda^2
1Radiology, Kanazawa Medical University, Kahoku, Japan, ²Thoracic surgery, Kanazawa Medical Universiy, Kahoku, Japan

The purpose of this study is to investigate the application of histogram analysis of ADC in determining the pathological grade of non-small cell lung cancer (NSCLC). The study included 54 patients and the histogram parameters were correlated with pathological grades. For the parameters that were significantly different between high- and low-grade tumors, ROC curve analysis was performed. The 95th percentile of ADC was the most beneficial parameter for distinguishing high-from low-grade tumors. ADC histogram analysis on the basis of the entire tumor volume is useful for predicting the pathological grade of NSCLC.

Kangjie Xu¹, Xiaodong Zhang¹, Chengyan Wang², Hongxia Sun¹, Yu Zhang³, Zhigang Wu⁴, Juan Wei⁵, and Xiaoying Wang^1
1The Department of Radiology, Peking University First Hospital, Beijing, China, People's Republic of, ²Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, People's Republic of, ³Philips Healthcare, Beijing, China, People's Republic of, ⁴Philips Healthcare (Suzhou) Co., Ltd (Suzhou), Suzhou, China, People's Republic of, ⁵Philips research China, Beijing, China, People's Republic of

This study aims to assess the clinical feasibility of high b value iZOOM on prostate and to validate whether it is superior to regular DWI at 3.0 T with 58 patients recruited in the study. The scan protocol included iZOOM and DWI with b value of 2000s/mm2. Subjective and objective evaluation was carried out from three aspects: the basic image quality, the display of lesions, and the overall image quality. Our study found that with the same high b value, iZOOM had better comprehensive image quality, less artifact and distortion yet similar contrast compared with regular DWI.

Sarah Keller¹, Fabian Kording¹, Hendrick Kooijman², Christoph Schramm³, Roland Fischer⁴, Adam Gerhard¹, Ansgar Lohse³, Harald Ittrich¹, and Jin Yamamura^1
1Diagnostic and Interventional Radiology, University Medical Center Hamburg Eppendorf (UKE), Hamburg, Germany, ²MRI, Philips GmbH, Hamburg, Germany, ³Department of Internal Medicine, University Medical Center Hamburg Eppendorf (UKE), Hamburg, Germany, ⁴Biochemistry, University Medical Center Hamburg Eppendorf (UKE), Hamburg, Germany

Hepatic osteodystrophy is a frequent complication in patients with chronic cholestatic and non-choleatatic liver disease, affecting up to 20-30% of patients [1, 2]. Besides conventional dual x-ray absorbtiometry (DXA) scans, diffusion-weighted MRI (DWI) has been performed for the evaluation of osteoporosis and osteopenia in risk patients. Follow up MRI examinations of PSC patients, to exclude malignancy and identify bile duct stenosis, are frequently performed in clinical routine. The aim of this study was to test the feasibility of add-on DWI sequences during routine examination for the detection of early changes of the bone marrow density (BMD) in comparison to DXA T-score values of the vertebral bone and healthy controls.

Chunchao Xia¹, Panli Zuo², David Porter³, Zhenlin Li⁴, and Bin Song^4
1West China Hospital, Chengdu, China, People's Republic of, ²Beijing, China, People's Republic of, ³Erlangen, Germany, ⁴Chengdu, China, People's Republic of

Readout-segment EPI (rs-EPI) is a new approach to reduce susceptibility artifacts and blurring in DWI. In this study, we qualitatively and quantitatively compare the images quality of ss-EPI and rs-EPI for rectal cancer DWI

Weimin An¹, Jing Lei¹, Changchun Liu¹, and Jinghui Dong^1
1302 military hospital of China, Bei Jing, China, People's Republic of

This study is designed to investigate whether ADC values of lipid-containing small HCC with different pathological grading are the same as well as the correlation of ADC values with the pathological differentiate degree. There was significant difference between low-grade group and moderate-grade group, as well as between low-grade group and high-grade group (P <0.05), and there was obviously  significant difference between moderate-grade and high-grade group (p <0.05). Meanwhile, there was moderately positive correlation between ADC value and pathological grading of lipid-containing small HCC (P=0.002, r=0.419) and the coefficient of association was 0.95.  This study demonstrated ADC value can distinguish different pathological grading of lipid-containing small HCC, and there is moderately positive correlation between them. 

Andrea Agostini¹, Mitchell Raeside¹, Richard Do¹, Amita Shukla-Dave², David Aramburu Nunez², Ramesh Paudyal², Olga Smelianskaia¹, Maggie Fung³, Monika Khan¹, David Kelsen⁴, Gabriella Carollo⁵, and Lorenzo Mannelli^1
1Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ²Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ³Global MR Applications and Workflow, GE Healthcare, New York, NY, United States, ⁴Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ⁵Saint Vincent Ferrer High School, New York, NY, United States

The aim of the study is the qualitative and quantitative evaluation of Diffusion-weighted images (DWI) with reduced field-of-view (rFOV), that are incorporated into a fast rapid MR pancreas screening protocol (MRpsp). We are developing a fast rapid MRpsp to be performed in carriers of BRCA mutations after a breast MRI, using the built-in body coil of a 3T magnet without repositioning a patient who is in the prone position. 15 patients were scanned. For b-values <100 s/mm², b=20 s/mm² DWI had the best contrast-to-noise and signal-to-noise ratios. Among b-values >100 s/mm², b=250 s/mm² DWI showed the highest diagnostic information.

Yasuhiro Goto¹, Kenji Fukushima², Masami Yoneyama³, Atsushi Takemura³, Hitoshi Tadenuma¹, Mamoru Takeyama¹, and Shuji Sakai^2
1Department of Radioligical Service, Tokyo Women's Medical University Hospital, TOKYO, Japan, ²Department of Diagnostic imaging & Nuclear Medicine, Tokyo Women`s Medical University Hospital, Tokyo, Japan,³Philips Electronics Japan, Tokyo, Japan

We evaluated the feasibility of optimal gating method and imaging parameters for Single-Shot Turbo Spin Echo (ssTSE) diffusion weighted image (DWI). As a result, The Peripheral pulse gating (PPG) synchronization method was significantly higher in visual scoring than that of the ECG synchronization method (p=0.02) and ssTSE-DWI using SENSE-factor 4.0 brought about the best image quality. Refocusing Flip Angle (RFA) tended to be higher in images with higher visual score. Visualizing cardiac DWI was feasible under above conditions. In conclusion, it is expected that ssTSE-DWI using PPG has a possibility to detect abnormal signal from myocardium by non-contrast MRI.

Jinliang Niu¹, Wenqi Wu¹, Tong Gong¹, Wenjin Li¹, Dandan Zheng², Zheng Zhong³, Hongwei Wang¹, and Xiaohong Joe Zhou^3
1The Second Hospital of Shanxi Medical University, Taiyuan, China, People's Republic of, ²GE Healthcare MR Research China, Beijing, China, People's Republic of, ³Center for Magnetic Resonance Research, University of Illinois Hospital &Health Sciences System, Chicago, IL, United States

MRI has become preferred over other imaging modalities in evaluating marrow compositions. Although the routine MRI can evaluate the cellularity of marrow according to signal intensity, it’s not quantitative analysis. IVIM provides both diffusion and perfusion quantification using a single imaging study at the same time, without intravenous contrast injection. IVIM has been applied in various diseases, but the application of IVIM in marrow composition is less. As the preliminary study, we will adopt the parameters of IVIM to assess the vertebral bone marrow microstructure, then to investigate gender-related cellular and capillary network of vertebral marrow in healthy young adults. 

Yuguang Meng¹ and Xiaodong Zhang^1,2
1Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States, ²Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States

      Non-human primates mimick most aspects of humans and are widely used in preclinical or medical studies. Understanding the structural connectivity in non-human primate brains can provide essential reference for translational research. The characterization of the corticospinal tracts plays a crucial role in motor function and has been well studied in human brain. However, it remains not fully understood in non-human primates. In this work, high angular resolution diffusion imaging (HARDI) tractography was utilized to evaluate the corticospinal tracts distribution in sub-regions of motor cortices of adult macaque monkeys, and high similarity to prior ex-vivo results was observed.

Daniel Svärd^1,2, Markus Nilsson³, Björn Lampinen⁴, Jimmy Lätt², Pia Sundgren^1,2, Erik Stomrud⁵, Lennart Minthon⁵, Katarina Nägga⁵, Oskar Hansson^5,6, and Danielle van Westen^1,2
1Diagnostic Radiology, Clinical Sciences, Lund University, Lund, Sweden, ²Center for Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden, ³Lund University Bioimaging Center, Lund University, Lund, Sweden, ⁴Department of Medical Radiation Physics, Lund University, Lund, Sweden, ⁵Clinical Memory Research Unit, Clinical Sciences, Lund University, Malmö, Sweden, ⁶Neurology, Clinical Sciences, Lund University, Lund, Sweden

White matter lesions (WML) are common in cognitively healthy elderly and their presence in a brain region is associated with elevated mean diffusivity (MD) and reduced fractional anisotropy (FA). We compared patients with amnestic mild cognitive impairment (aMCI) to control groups with different prevalence of WML. Our results showed that including subjects with WML in the control group highly influence the outcome of statistical analysis of diffusion tensor imaging (DTI) metrics. We conclude that WML should be taken into consideration when designing and interpreting DTI studies.

Frederick C. Damen^1,2, Matthew Lindeblad³, Kejia Cai^2,4, Michael Flannery², Yi Sui², Amelia M Bartholomew⁵, Aleksander V Lyubimov³, and Xiaohong Joe Zhou^2,4,6,7
1Radiology, University of Illinois at Chicago, Chicago, IL, United States, ²Center for Magnetic Resonance Research, University of Illinois at Chicago, Chicago, IL, United States, ³Pharmacology, University of Illinois Medical Center, Chicago, IL, United States, ⁴Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, ⁵Surgery, University of Illinois Medical Center, Chicago, IL, United States, ⁶Radiology, Chicago, IL, United States, ⁷Neurosurgery, University of Illinois at Chicago, Chicago, IL, United States

The purpose of this study is to characterize Hematopoietic Acute Radiation Syndrome (hARS) and assess the effect of total body irradiation in a Göttingen minipig model using quantitative diffusion MRI. The minipigs were irradiated at a total dose of either 1.65 Gy (LD30/45 days) or 1.90 Gy (LD70/45 days). The animals underwent diffusion MRI scans prior to and again at 8, 15, or 22 days following irradiation.  The consistent diffusion value prior to irradiation and the significant changes post-irradiation, both observed in this study, suggest that quantitative diffusion MR can be a viable marker for studying the effect of total body irradiation.

Manoj Kumar Sarma¹, Margaret Keller², Rajakumar Nagarajan¹, David E Michalik³, Judy Hayes², Karin Nielsen-Saines⁴, Jaime Deville⁴, Joseph A Church⁵, Irwin Walot⁶, and M. Albert Thomas^1
1Radiological Sciences, UCLA School of Medicine, Los angeles, Los Angeles, CA, United States, ²Pediatrics, Harbor-UCLA Medical Center, Torrance, CA, United States, ³Infectious disease-Pediatrics, Miller’s Children’s Hospital of Long Beach, Long Beach, CA, United States, ⁴Pediatrics, UCLA School of Medicine, Los angeles, Los Angeles, CA, United States, ⁵Pediatrics, Children’s Hospital Los Angeles, Los Angeles, CA, United States,⁶Radiology, Harbor-UCLA Medical Center, Torrance, CA, United States

DTI was used to derive in vivo tissue status measurements of subcortical brain regions that are vulnerable to injury in perinatally HIV-infected youths. Quantitative measurements, including the mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD) were determined in of the whole brain in 12 well-characterized HIV youths and in 12 healthy control subjects. We observed widespread brain regions with increased AD values in perinatally HIV-infected youths compared to healthy controls, indicating axonal changes. We also observed increased FA, MD and RD. To confirm these findings a correlation study with neurodevelopement and neurocognitive changes as well as ART effect is needed. Understanding the impact of HIV disease severity on white matter integrity provides potentially useful clinical tools for evaluating ART efficacy during a dynamic period of brain development.

Youping Xiao¹, Yunbin Chen¹, Jianji Pan², Dechun Zheng¹, Xiang Zheng¹, and Ying Chen^1
1Radiology, Fujian Provincial Cancer Hospital, Fuzhou, China, People's Republic of, ²Radiation Oncology, Fujian Provincial Cancer Hospital, Fuzhou, China, People's Republic of

In this present study, by applying the special mouse coil(4 channel), IVIM-DWI with 14 b-factors(0~1000s/mm²) was successfully conducted on nude mice with different radio-sensitive NPC xenografts(CNE-1 and CNE-2) during the course of fractional radiations. The IVIM-DWI parameters of xenografts were found to change characteristically after fractional radiations and were significantly different between different radio-sensitive NPC xenografts, and their corresponding changes also behaved significant correlations with the pathological features of NPC xenografts. Thus, it is suggested IVIM-DWI parameters be valuable in evaluating the micro-structures and radio-sensitivity of NPC xenografts.

CY Wang¹, R Zhang², L Jiang³, R Wang⁴, XD Zhang⁴, H Wang³, K Zhao⁴, LX Jin³, J Zhang^1,2, XY Wang^1,4, and J Fang^1,2
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, People's Republic of, ²College of Engineering, Peking University, Beijing, China, People's Republic of, ³Philips Healthcare, Suzhou, China, People's Republic of, ⁴Department of Radiology, Peking University First Hospital, Beijing, China, People's Republic of

The sequence most commonly used in renal DWI is based on single-shot echo-planar imaging (SS-EPI), which is prone to artifacts and distortions related to susceptibility and eddy currents. Reducing these artifacts and distortions in SS-EPI generally requires a reduced field of view (rFOV) in the phase-encoding direction and/or reduced spatial resolution. To resolve these problems, a 2D rFOV-DWI sequence was introduced for imaging and further IVIM modeling. Compared with conventional full-FOV single-shot DWI techniques, rFOV-DWI methods generally produced images of superior quality. With the application of IVIM model, it is possible to evaluate single renal diffusion and perfusion simultaneously.

Ralf Lützkendorf¹, Robin M. Heidemann², Thorsten Feiweier², Michael Luchtmann³, Sebastian Baecke¹, Joern Kaufmann⁴, Joerg Stadler⁵, Eike Budinger⁵, and Johannes Bernarding^1
1Biometry and Medical Informatics, University of Magdeburg, Magdeburg, Germany, ²Siemens Healthcare GmbH, Erlangen, Germany, ³Department of Neurosurgery, University of Magdeburg, Magdeburg, Germany, ⁴Department of Neurology, University of Magdeburg, Magdeburg, Germany, ⁵Leibniz Institute for Neurobiology, Magdeburg, Germany

Track-density imaging (TDI) is a method to generate super-resolution images from fiber-tracking data (1). Here, we applied this technique to 1.4 mm isotropic 7T whole brain diffusion MR imaging data (dMRI). Besides the well-known large and medium-sized fiber tracts the high resolution of the data allowed visualizing the complex interwoven courses of fiber tracts in the cerebellar-pontine angle as well as showing parts of the trigeminus nerve. Combining TDI with high-resolved diffusion data has a great potential for analyzing the anatomy in vivo of brain structures across different scales as well as the neuronal connectome throughout the whole brain.

Xiaoke Wang¹, Samir D Sharma², Mustafa R Bashir³, Jean H Brittain², Jean Shaffer³, Takeshi Yokoo⁴, Qing Yuan⁴, Scott B Reeder^1,2,5,6,7, and Diego Hernando^2
1Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ²Radiology, University of Wisconsin-Madison, Madison, WI, United States, ³Radiology, Duke University, Durham, NC, United States, ⁴Radiology, University of Texas Southwestern Medical Center, Dallas, TX, United States, ⁵Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ⁶Medicine, University of Wisconsin-Madison, Madison, WI, United States, ⁷Emergency Medicine, University of Wisconsin-Madison, Madison, WI, United States

A recently proposed acetone-D₂O phantom, which has ADC tunable over the entire physiological range, has shown promise for the development and quality assurance of quantitative diffusion MRI. In this study, this phantom was shipped between three sites with different MRI vendors to demonstrate consistent diffusion quantification across imaging protocols, platforms, and field strengths. The results demonstrated consistent ADC measurements across sites/vendors, field strength, choice of b-values, intra-exam and inter-exam repetition. In conclusion, the acetone-D₂O phantom is a promising tool for future multi-center validation and quality assurance of quantitative diffusion MRI techniques.

Dan Wu¹ and Jiangyang Zhang^1,2
1Radiology, Johns Hopkins University School of Medicine, BALTIMORE, MD, United States, ²Radiology, New York University School of Medicine, New Yourk, NY, United States

Intravoxel incoherent motion (IVIM) in the capillaries reflects capillary geometry and flow velocity, which may be probed by diffusion MRI measured at varying diffusion times. In this study, we employed flow-compensated pulsed and oscillating gradient sequences to investigate the diffusion time dependence of pseudo-diffusion in the mouse brain with diffusion times ranging from 2.5 ms to 40 ms. We used a simplified IVIM model to characterize the pseudo-diffusion compartment and flow compartment based on the relation between capillary segments and diffusion time/distance. Our results clearly demonstrated diffusion time dependence and suggested that the pseudo-diffusion fraction increased with increasing diffusion time.

Parisa Movahedi¹, Hanne Hakkarainen², Harri Merisaari¹, Heidi Liljenbäck¹, Helena Virtanen¹, Hannu Juhani Aronen¹, Heikki Minn¹, Matti Poutanen¹, Anne Roivainen¹, Timo Liimatainen², and Ivan Jambor^1
1University of Turku, Turku, Finland, ²A.I. Virtanen Institute for Molecular Sciences, Kuopio, Finland

Tumor growth in mice preclinical prostate cancer model (human prostate cancer cells, PC-3) was followed for 4 weeks by weekly DWI  in control group (n=10) and treatment group (n=9) receiving Docetaxel.  DWI data sets were acquired using 15 b-values in the range of 0-500s/mm² and 12 b-values the range of 0-2000 s/mm². The DWI signal decays were fitted using monoexponential, biexponential, kurtosis and stretched exponential models/functions. Bayesian shrinkage prior method and independent least squares fitting have been applied and fitting quality evaluated by corrected Akaike Information Criteria. Bayesian modeling improved quality of DWI parametric maps derived using high b-value DWI data sets. Our result does not support the use of biexponential, kurtosis and stretched exponential models/functions for low b value DWI data sets of PC-3 mice preclinical prostate cancer model.

Yong Zhang¹ and Yanfen Cui^2
1GE Healthcare China, Shanghai, China, Shanghai, China, People's Republic of, ²Department of Radiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China, People's Republic of

This study was to investigate the feasibility of IVIM DWI to evaluate the early therapeutic effects of ZD6474 upon human NPC xenografts in nude mouse. NPC mice underwent IVIM DWI at baseline and after 1, 3, and 7 days of treatment. In the treated group, the f and D* decreased significantly on day 1 while the ADC and D were significantly higher from day 3 compared with the control group, demonstrating that IVIM DWI is sensitive to detect the ZD6474-induced changes in human NPC nude mouse, and the D* and f parameters could predict early response to anti-angiogenic treatment.  
 

Lihua Chen¹, Tao Ren¹, Yu Zhang², Chenglong Wen¹, and Wen Shen^1
1Tianjin First Center Hospital, Tianjin, China, People's Republic of, ²Philips healthcare, Beijing, China, People's Republic of

To detect the changes of kidney diseases, magnetic resonance imaging(MRI) as a noninvasive approach has been proved to be more suitable for detecting and monitoring diabetic nephropathy(DN). Intravoxel incoherent motion (IVIM) and blood oxygenation level dependent (BOLD) MR imaging have been confirmed their high potential in detecting changes of renal function in patients with chronic renal diseases and transplanted kidneys. We compared the parameters of IVIM and BOLD in patients with DN and heathy controls. The results demonstrated the capacity of IVIM and BOLD for reflecting renal perfusion, diffusion and oxygenation changes in patients with DN. 

Grinberg Farida^1,2, Ivan I. Maximov^1,3, Ezequiel Farrher¹, Irene Neuner^1,4,5, Eileen Oberwelland^6,7, Kerstin Konrad^5,6,8, and N. Jon Shah^1,2,5
1Institute of Neuroscience and Medicine - 4, Forschungszentrum Juelich GmbH, Juelich, Germany, ²Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany, ³Experimental Physics III, TU Dortmund University, Dortmund, Germany, ⁴Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Aachen, Germany, ⁵JARA - BRAIN - Translational Medicine, Aachen, Germany, ⁶Institute of Neuroscience and Medicine – 3, Forschungszentrum Jülich GmbH, Juelich, Germany, ⁷Translational Brain Research in Psychiatry and Neurology, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, RWTH Aachen University, Aachen, Germany, ⁸Child Neuropsychology Section, Department of Child and Adolescent Psychiatry and Psychotherapy, RWTH Aachen University, Aachen, Germany

Diffusion tensor imaging has enabled the examination of white matter connectivity and microstructural changes across the lifespan. However, the detection of subtle microstructural changes during typical brain maturation still remains challenging. Recently, diffusion kurtosis imaging has attracted much attention as an efficient method for characterising non-Gaussian water diffusion in brain tissue. Here, we tested whether diffusion kurtosis imaging can extend our knowledge of changes in brain tissue microstructure related to normal brain development. We showed that diffusion kurtosis imaging provides useful biomarkers sensitive to the level of maturity in association, projection and commissural fibres. 

Bin Zhang¹, Long Liang¹, Yuhao Dong¹, Kannie W.Y. Chan², Guanshu Liu², Changhong Liang¹, and Shuixing Zhang^1
1Department of Radiology, Guangdong Academy of Medical Sciences/Guangdong General Hospital, Guangzhou, China, People's Republic of, ²Russell H. Morgan Department of Radiology and Radiological Sciences, Division of MR Research, The Johns Hopkins University School of Medicine, Baltimore 21287, USA, Baltimore, AL, United States

Contrast-induced acute kidney injury (CI-AKI) is a common iatrogenic event caused by the injection of iodinated contrast agent, and remains the third major source of in-hospital acquired acute renal failure.The objective of our study is to examine the feasibility of using Intravoxel Incoherent Motion (IVIM) MRI to simultaneously measure the pathological changes in kidney diffusion and perfusion in the course of CI-AKI.  Our results showed that the kidney perfusion and diffusion as measured by IVIM are well-correlated with those measured using conventional methods, indicating IVIM MRI can be used as an effective tool for the diagnosis and staging of CI-AKI. 

Chao-Yu Shen^1,2,3, Zhen-Hui Li¹, Vincent Chin-Hung Chen⁴, Ming-Chou Ho⁵, Yeu-Sheng Tyan^1,2, and Jun-Cheng Weng^1,2
1Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, ²Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan,³Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan, ⁴Department of Psychiatry, Chang Gung Memorial Hospital, Chiayi, Taiwan, ⁵Department of Psychology, Chung Shan Medical University, Taichung, Taiwan

Major depressive disorder (MDD) is the most common mood disorder in the world and the most important precursor of suicide. Despite decades of research, the pathophysiology of MDD remains not well understood. Recently, several MRI studies have focused on structural and functional connectivity evaluation and suggested that alterations of some specific regions of the brain, in both gray and white matter structures and some specific cortical–subcortical neuronal circuits, may play important roles of MDD. Generalized q-sampling imaging (GQI) is a more accurate and sophisticated diffusion MR approach compared to diffusion tensor imaging (DTI), which can extract additional information about the altered diffusion environments to resolve the complicated neural structure changes of neural disease. In this study, we used GQI and graph theoretical analysis to evaluate brain structure and connectivity change of MDD compared to healthy controls and correlation with symptom severity. Our results indicated  GQI indices can help to detect structural and connective abnormalities of MDD patients and these alterations are correlated with depressive severity. 

Chengxu Li¹, Tianyi Qian², Jinsuh Kim³, Philip Zhe Sun⁴, Jie Lu¹, and Kuncheng Li^1
1Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, China, People's Republic of, ²MR Collaborations NE Asia, Siemens Healthcare, Beijing, China, People's Republic of, ³Department of Radiology, University of Illinois at Chicago, Chicago, IL, United States, ⁴Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States

Conventional DKI is limited in use for detecting acute stroke because of its relatively long scan time and current need of offline processing. Here we used a 13 directions protocol combined with simultaneous multi-slice technique with inline reconstruction to test the diffusion pattern at different time points. The results shows the lesion size observed within 24hr on MK matched with the lesion size on T2-FLAIR after one month, which was better than lesion size observed within 24hr on DWI. Early application of the fast DKI to detect the anomalous range of MK was beneficial to predict the range of the eventual infarction for clinical treatment.

Stefan Sommer^1,2, Nadja Doerig^3,4, Janis Brakowski², Martin grosse Holtforth⁵, Sebastian Kozerke¹, Erich Seifritz^2,4, Simona Spinelli^2,4, and Philipp Stämpfli^2
1Institute for Biomedical Engineering, ETH and University of Zurich, Zurich, Switzerland, ²Department of Psychiatry, Psychotherapy and Psychosomatics Psychiatric Hospital, University of Zurich, Zurich, Switzerland,³Division Neuropsychology, Departement of Psychology, University of Zurich, Zurich, Switzerland, ⁴Neuroscience Center, University and ETH Zurich, Zurich, Switzerland, ⁵Department of Psychology, University of Bern, Bern, Switzerland

In the last few years, tract base spatial statistics (TBSS) and automating fiber-tract quantification (AFQ) have become prominent tools for analyzing diffusion data in group studies. In this study, we introduce optimized high-resolution tract density (optTD) images and analyze these maps using TBSS and AFQ in patients with major depressive disorders. We show a higher sensitivity in the newly introduced optTD compared to traditional FA analyses. Significant group differences were found using both methods indicating robust findings. High resolution optTD maps derived from optimized tractograms provide a promising tool for investigating white-matter abnormalities in mental disorders.

Xilun Ma¹, Jitian Guan¹, Zhiyan Zhang¹, Miaomiao Chen¹, Yanzi Chen¹, Zhiwei Shen¹, and Renhua Wu^1
1Department of Medical Imaging, the 2nd Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China, Shantou, China, People's Republic of

Eighteen Parkinson Disease’s (PD) patients and four healthy controls(HC) underwent the diffusional kurtosis imaging (DKI) and then we tested the PD’s patients with Hoehn-Yahr scale and Unified Parkinson Disease Rating Scale(UPDRS). As a result, we found a significant decrease of Mean kurtosis (MK) values in the left substantia nigra between PD’s patients and healthy controls. Moreover, the kurtosis fractional anisotropy (KFA) values in right red nucleus of the PD’s patients were positively associated with the UPDRS scores in our study.

Guangyu Wu¹ and Yongming Dai^2
1renji hospital, shangha, China, People's Republic of, ²MR, Philips Healthcare, Shanghai, China, People's Republic of

A wide spectrum of the use of DKI to characterize non-Gaussian diffusion pattern in microstructural tumor tissue has been developed involving a variety of tumors. However, the feasibility of DKI in kidney has been assessed in healthy volunteers only. The study was assigned to assess the quantitative DKI in grading of clear cell renal carcinoma (ccRCC) and to compare the correlation between DKI parameters and tumor cellularity and found that DKI could not only quantitatively characterize ccRCC with different grades but also provide valuable information on the diffusion properties related to tumor microenvironment changes or tissue complexity in tumor.

Chanon Ngamsombat ¹, Zhe Zhang², Hua Gua², Theerapol Witthiwej³, Weerasak Muangpaisan⁴, Sith Sathornsumetee⁵, Suwit Charoensak⁶, Panida Charnchaowanish¹, and Orasa Chawalparit^1
1Department of Radiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, Bangkok, Thailand, ²Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, Beijing, China, People's Republic of, ³Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, Bangkok, Thailand,⁴Department of Preventive and Social Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, Bangkok, Thailand, ⁵Departments of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, Bangkok, Thailand, ⁶Department of Psychiatry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, Bangkok, Thailand

Idiopathic normal pressure hydrocephalus(iNPH) is important reversible cause of dementia and gait abnormality in elderly patients. Diffusional kurtosis imaging(DKI) moreover explains the complexity of white matter abnormality with inclusion of non-Gaussian effects. We aim to identify difference of complexity of white matter alteration in iNPH patients before and after shunt placement surgery by using high resolution DKI. We report significant increase of mean diffusional kurtosis(Kmean), mean diffusivity(MD) and decrease of radial diffusional kurtosis(Krad) , fractional ansiotropy(FA) after shunt placement surgery. High resolution DKI can be used for monitoring and detection complexity of white matter alteration in iNPH patients.

Huiying Kang¹, Ningning Zhang, Kaining Shi², Yanqiu Lv¹, Di Hu¹, and Yun Peng^1
1Imaging center, Beijing Children’s Hospital, Capital Medical University, Beijing, China, People's Republic of, ²Imaging Systems Clinical Science, Philips Healthcare, Beijing, China, People's Republic of

Increasing clinical studies suggested that there are some type ? Gaucher disease (GD?) patients suffering neurological symptom, which was originally defined as non-neuropathlogical involved. This study recruited 38 patients and 32 normal children to investigate morphological changes of brain in GD? patients by using Diffusion Kurtosis Imaging. Our results showed significant decreased MD in bilateral olfactory gyrus, increased MD in right calcarine and substantia nigra and significant increased MK in right olfactory gyrus. Our study suggests a necessity of adjusting the opinion regarding the CNS-involvement of GD?, and DKI analysis is a potential imaging marker in clinical studies of GD?.

Haojie Li¹, Lili Liang¹, Anqin Li¹, Qiong Li¹, Yao Hu¹, Hui Lin², Daoyu Hu¹, and Zhen Li^1
1Departments of Radiology, Tongji Hospital, Tongji Medical College, WU HAN, China, People's Republic of, ²GE Healthcare,MR Research China,WU HAN, WU HAN, China, People's Republic of

Since DWI with different models may demonstrate different aspects of tissue properties, it should be valuable to compare and explore their roles in renal tumors. To our knowledge, however, no comparison of these different diffusion imaging approaches for the differential diagnosis in renal tumors has been investigated so far. The purpose of this study was to quantitatively compare and evaluate the potential clinical value of various diffusion parameters obtained from monoexponential, biexponential, and stretched exponential DWI models for differentiation of MFAML from ccRCC.