Sabrina Klix¹, Andreas Pohlmann¹, Jan Hentschel¹, Karen Arakelyan^1,2, Mandy Fechner³, Kathleen Cantow², Bert Flemming², Sonia Waiczies¹, Erdmann Seeliger², and Thoralf Niendorf^1,4
1Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine, Berlin, Germany, ²Institute of Physiology, Charité Universitaetsmedizin, Berlin, Germany, ³Nephrology and Intensive Care Medicine, Campus Virchow-Klinikum and Center for Cardiovascular Research, Charite-Universitaetsmedizin Berlin, Berlin, Germany, ⁴Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max Delbrueck Center for Molecular Medicince, Berlin, Germany

Minkowski Functionals (MFs) allow a quantitative analysis of tissue heterogeneity – independent of absolute values, which can be biased by magnetic field strength, B₀ homogeneity, voxel size, etc. Here we applied this technique to characterize renal cortical and medullary T₂^* heterogeneity in order to test the feasibility of a differentiation between healthy kidneys, and kidney injuries.

Lei Jiang¹, Paul Territo¹, Brian McCarthy¹, Amanda A. Riley¹, Sourajit Mustafi¹, Yu-Chien Wu¹, Bruce Molitoris², Gary Hutchins¹, and Chen Lin^1
1Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States, ²Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States

The objective of this study is to evaluate the capability of quantitative MRI techniques to measure physiological changes associated with changes in renal function in a rat model. Our investigation suggest that the results of T₂* mapping, intra-voxel incoherent motion (IVIM), and T1ρ imaging are comparable to the published results. These techniques can be used to assess and monitor different aspects of physiological changes in kidney fibrosis.

Chengyan Wang¹, Rui Zhang², Li Jiang³, Rui Wang⁴, Xiaodong Zhang⁴, He Wang³, Kai Zhao⁴, Lixin Jin³, Jue Zhang^1,2, Xiaoying Wang^1,4, and Jing 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

Renal oxygenation plays a major role in the evaluation of renal function and has attracted considerable attention in recent years. This study demonstrates the feasibility of using a susceptibility-based MRI technique for measuring renal oxygen extraction fraction (OEF) change under the influence of carbogen (97% O2, 3% CO2) breathing.  Significant decrease of renal OEF was found during carbogen challenge. Furthermore, the efficacy of this susceptibility-based method was proved by blood pO2 measurement.

Xiaodong Zhang¹, Yue Mi², Jing Wang³, Jingyun Wu¹, Rui Zhang⁴, Yan Sun¹, Xiaoying Wang^1,4, Jue Zhang⁴, and Hongyu An^5
1Department of Radiology, Peking University First Hospital, Beijing, China, People's Republic of, ²Department of Urology, Peking University First Hospital, Beijing, China, People's Republic of, ³Center for medical device evaluation, China Food and Drug Administration, Beijing, China, People's Republic of, ⁴Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, People's Republic of, ⁵Department of Radiology and Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

Quantitative measurement of renal oxygen metabolism level is of central importance in understanding and treating renal diseases and renal metabolic rate of oxygen (RMRO2) can provide a valid criterion for evaluation the renal tissue oxygen metabolism level under both normal and disease states. According to the Fick principle of arteriovenous oxygen difference, the RMRO2 can be estimated by using a qBOLD and ASL technique. In this study, we will demonstrate the ability to obtain absolute quantitative RMRO2 noninvasively in normal and unilateral renal artery stenosis rabbits.

Luke Xie¹, Vivian S. Lee², Hongjiang Wei³, Yi Qi⁴, Susan B. Gurley⁵, G. Allan Johnson⁴, and Chunlei Liu^3
1Radiology, University of Utah, Salt Lake City, UT, United States, ²Utah Center for Advanced Imaging Research, Radiology, University of Utah, Salt Lake City, UT, United States, ³Brain Imaging Analysis Center, Radiology, Duke University Medical Center, Durham, NC, United States, ⁴Center for In Vivo Microscopy, Radiology, Duke University Medical Center, Durham, NC, United States, ⁵Medicine-Nephrology, Duke University Medical Center, Durham, NC, United States

BOLD MRI via T₂* mapping can detect changes in kidney injuries. However, BOLD MRI can be insensitive and the source of signal change is not clear. Quantitative susceptibility mapping (QSM) is very sensitive to molecular composition and can identify sources as paramagnetic, such as deoxygenated hemoglobin. In this study, we applied QSM to characterize the source of signal change and compared it with BOLD T₂* maps. We used a model of ischemia reperfusion in mouse kidneys and imaged at 1 hr, 1 day, 7 days, and 14 days after injury.

Tao Ren¹, Pan-Li Zuo², Thorsten Feiweier³, Niels Oesingmann⁴, Andre-de Oliveira³, Li-Hua Chen⁵, Cheng-Long Wen⁵, and Wen Shen^5
1Radiology, Tianjin Medical University First Center Hospital, Tianjin, China, People's Republic of, ²Beijing, China, People's Republic of, ³Erlangen, Germany, ⁴New York, NY, United States, ⁵Tianjin, China, People's Republic of

We performed intravoxel incoherent motion(IVIM), arterial spin labeling(ASL) and T1 mapping MR imaging in 62 renal allograft recipients to determine the diagnostic values of each parameter in renal allograft function evaluation. We found that cortical ADC, ADCslow, ADCfast, PF and RBF were lower for allografts with impaired function than with good function, and T1 values were higher for allografts with impaired function than with good function (P <0.05). ADC derived from IVIM and RBF derived from ASL showed a higher diagnostic efficacy to discriminate between allografts with impaired function and allografts with good function. 

Sourajit Mitra Mustafi¹, Paul R. Territo¹, Brian P. McCarthy¹, Amanda A. Riley¹, Jiang Lei¹, Chen Lin¹, Qiuting Wen¹, Bruce A Molitoris², Gary D. Hutchins¹, and Yu-Chien Wu^1
1Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, United States, ²Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States

In this study, we used multi-shell diffusion-weighted imaging in an animal model of Chronic Kidney Disease (CKD).  We focus on the functional changes in the kidney using diffusion tensor imaging (DTI) and q-space imaging (QSI).  Four Wistar rats received surgical procedure to induce ischemic fibrosis in their left kidney.  The multi-shell diffusion-weighted imaging was performed on the acute stage, day 2 after the surgery.  In the acute stage, the renal medulla showed significant decrease in overall diffusivity measured by DTI and increase in tissue restriction measured by q-space imaging.

Christopher Charles Conlin^1,2, Yangyang Zhao², Yufeng Huang³, and Jeff Lei Zhang^1,4
1Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT, United States, ²Bioengineering, University of Utah, Salt Lake City, UT, United States, ³Nephrology, University of Utah School of Medicine, Salt Lake City, UT, United States, ⁴Radiology, University of Utah School of Medicine, Salt Lake City, UT, United States

This study examined the suitability of T2 and ASL-measured renal perfusion as biomarkers for fibrotic kidney disease. Renal perfusion was measured in healthy and fibrotic rats using a multi-TI ASL protocol and compared to renal T2 as well as urinary and histological fibrosis markers. Significantly reduced renal perfusion was observed in fibrotic rats, in parallel with increased renal T2, proteinuria, and mesangial matrix in the glomerular tuft. The sensitivity of T2 and perfusion to fibrotic kidney damage suggests that ASL and T2-weighted MRI may provide improved assessment of renal fibrosis and prove useful for the early detection of renal disease.

Cheng long Wen¹, Lihua Chen¹, Fan Mao¹, Yu Zhang², and Wen Shen^1
1Department of Radiology, Tianjin First Center Hospital, Tianjin, China, Tianjin, China, People's Republic of, ²Philips healthcare, Beijing, China., Beijing, China, People's Republic of

The goal of this pilot study was to assess the ADC value in kidney of IVIM and DTI in distinguishing diabetic subjects and healthy controls. In our study, cortical ADC and D of patients with DN were significantly lower than those of healthy controls. The reduction of D values in the cortex and medulla was more obvious than ADC in patients. The results of this study suggested that cortical D and ADC, quantified by kidney IVIM and DTI could be potential imaging biomarkers for DN. IVIM could reflect the renal function more sensitive and accurate in DN patients.

Tao Ren¹, Pan-Li Zuo², Thorsten Feiweier³, Niels Oesingmann⁴, Andre-de Oliveira³, Li-Hua Chen⁵, Cheng-Long Wen⁵, and Wen Shen^5
1Radiology, Tianjin Medical University First Center Hospital, Tianjin, China, People's Republic of, ²Beijing, China, People's Republic of, ³Erlangen, Germany, ⁴New York, NY, United States, ⁵Tianjin, China, People's Republic of

We collected 20 volunteers and 62 renal allograft recipients who underwent intravoxel incoherent motion (IVIM) and arterial spin labeling (ASL) MRI. Comparing cortical perfusion indices, ADCfast and PF derived from IVIM with RBF derived from ASL in native and transplanted kidneys. We found that mean cortical RBF exhibited a significant correlation with PF (R =0.50, P <0.05) in the native kidneys, but both with ADCfast (R =0.26, P <0.05) and PF (R =0.32, P <0.05) in renal allografts. ADCfast and PF are effective indices for monitoring renal perfusion, as well as RBF.

Iris FRIEDLI¹, Lindsey Alexandra CROWE¹, Sophie DE SEIGNEUX², and Jean-Paul VALLEE^1
1Department of Radiology, Geneva University Hospitals, Geneva, Switzerland, ²Department of Nephrology, Geneva University Hospitals, Geneva, Switzerland

Diffusion-Weighted Imaging (DWI) allows the non-invasive assessment of the whole kidney. However, multi-slice DWI remains challenging because of artifacts, such as motion, partly related to the multi-slice acquisition. Despite the use of physiological triggering schemes to limit respiratory artifacts, kidney images can be impacted by the presence of inhomogeneous signal dropout causing slice-to-slice signal variation of signal intensity and Apparent Diffusion Coefficient (ADC). In this study, we highlight the presence of signal dropout in DWI and ADC maps, and present feasibility of a novel motion and signal correction algorithm to provide robust renal DWI.

Thomas Stokholm Nørlinger¹, Per Mose Nielsen¹, Emmeli Mikkelsen¹, Haiyun Qi¹, Kasper Hansen², Peter Kolstrup Agger³, Nikolaj Schmidt², Michael Pedersen², Hans Stødkilde-Jørgensen¹, Frederik Palm⁴, and Christoffer Laustsen^1
1Department of Clinical Medicine, MR Research Centre, Aarhus, Denmark, ²Department of Clinical Medicine, Comparative Medicine Lab, Aarhus, Denmark, ³Dept. of Cardiothoracic and Vascular Surgery, Aarhus, Denmark, ⁴Department of Medical and Health Sciences, Division of Drug Research, Linköping, Sweden

Hyperbaric oxygen therapy (HBO) is a well-known adjuvant treatment for several medical conditions indicated by the Undersea and Hyperbaric Medical Society. It is generally well tolerated and the kidneys display no adverse side effects after HBO. In diabetes hypoxia has been shown to be an important contributing factor in the development of diabetic nephropathy. In this experiment we investigate whether HBO has a protective effect on the kidney by preventing metabolic derangement as a consequence of hypoxia in the diabetic kidneys.

Inna Linnik¹, Parisa Ranjzad², Adrian S Woolf², and Steve R Williams^1
1University of Manchester, Centre for Imaging Scienses, Manchester, United Kingdom, ²University of Manchester, Institute of Human Development, Manchester, United Kingdom

To assess progressive kidney disease in a folic acid (FA) induced nephropathy model in mice, kidney T₁ and volume were quantified using MRI. Mice were imaged at 7 T before and at 1, 4 and 6 weeks after FA orvehicle injection. One week after FA, T₁ was significantly higher (P≤0.036) compared to control and correlated with kidney volume (R=0.90). Mice with marked T₁ and volume increases 1 week after FA demonstrated severe  fibrosis on histology at week 6. In conclusion, T₁ mapping may provide a marker of the initiation and severity of later chronic kidney disease.

Jose Angelo Udal Perucho¹, Elaine Yuen Phin Lee¹, and Queenie Chan^2
1Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong, Hong Kong, ²Philips Healthcare, Hong Kong, Hong Kong

Histogram analysis of intravoxel incoherent motion (IVIM) diffusion-weighted MRI (DWI) could be a promising quantitative approach in assessing tumour heterogeneity. We retrospectively studied thirty-five treatment-naïve patients with cervical cancer who had IVIM MRI examinations to determine to the value of IVIM histogram analysis, as a means of assessing tumour heterogeneity, in relationship with clinical staging. We observed statistically significant differences in most histogram parameters of f (perfusion fraction) between patients with early and locally advanced disease but only three histogram parameters of D (true diffusion coefficient) were statistically different in patients with early and locally advanced cervical cancer. 

Marissa Albert¹, Genevieve Bennett¹, Jonathan Melamed², and Nicole Hindman^1
1Radiology, NYU School of Medicine, New York, NY, United States, ²Pathology, NYU School of Medicine, New York, NY, United States

Mature cystic teratomas of the ovary are a common ovarian neoplasm, particularly in young patients. The majority of these neoplasms are benign; only a small minority demonstrates malignant potential. Distinguishing benign from malignant tumors is difficult on imaging alone, but has important clinical implications with regards to follow up and surgical excision. This study is the first in the literature to describe the incidence of, and type of, noduar enhancement within benign mature cystic teratomas.  Fat containing ovarian lesions with an internal nodule demonstrating peripheral enhancement and internal fat, along with acute angles and lack of extension beyond the cystic wall, can be confidently diagnosed as having a benign nodule and thus compatible with benign mature cystic teratoma. 

Yusaku Moribata¹, Aki Kido¹, Koji Fujimoto¹, Yuki Himoto¹, Yasuhisa Kurata¹, Fuki Shitano¹, Kayo Kiguchi¹, Ikuo Konishi², and Kaori Togashi^1
1Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan, ²Department of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan

There has been no previous report on the utility of computed DWI with b-values above 1000 s/mm² for the evaluation of cervical cancer. We aimed to evaluate the utility of computed DWI in cervical cancer and investigate the optimal b-value using computed DWI with b-values of 800, 1000, 1300, 1600 and 2000 s/mm². Computed DWI with b-values of 1300 or 1600 s/mm² may be recommended for the clinical evaluation of the extent of cervical cancer.

James Brittin¹, Elizabeth Sadowski¹, Kristin Bradley², and Jessica Robbins^1
1Radiology, University of Wisconsin, Madision, WI, United States, ²Radiation Oncology, University of Wisconsin, Madision, WI, United States

In our study of patients with cervical cancer, after initial treatment, tumors that recurred tended to have a higher heterogeneity on BOLD R2* maps, and tended to have a positive skew in their image histogram. As tumors undergo treatment, the AUC and skewness decreases significantly. Our findings indicate that BOLD MRI texture analysis can be used to assess long-term response to therapy after initial treatment and to follow tumors during treatment.  Further studies using BOLD MRI texture analysis in cervical cancer may help elucidate the utility of this technique in the course of treatment of women with cervical cancer.

Alana Amarosa Lewin¹, Genevieve Bennett¹, and Nicole Hindman^1
1Radiology, New York University School of Medicine, New York, NY, United States

The goal of this investigation was to determine the incidence of findings in asymptomatic patients which were suggestive of outflow obstruction (venous or lymphatic) as evidenced by dilated lymphatics and ovarian engorgement/signs of massive ovarian edema and to correlate these findings with the size of the fibroid uterus as compared to an age matched control population without fibroids.  Ovarian edema and/or lymphatic dilatation was noted with increased frequency in asymptomatic patients imaged for fibroid uterus over asymptomatic female patients without a fibroid uterus imaged for other causes (p< 0.0001).  Ovarian edema and/or dilated lymphatics in the setting of large fibroid uteri may be due to vascular congestion or lymphatic obstruction.  In the absence of pain and symptoms concerning for ovarian torsion, we postulate that these are incidental findings and recommend conservative management as opposed to immediate surgical exploration. 

Junko Takahama¹, Hiroshi Kobayashi², Chiharu Yoshimoto², Hiroshi Shigetomi², Masato Uchikoshi³, Takuya Iwabuchi⁴, Nagaaki Marugami¹, and Kimihiko Kichikawa^1
1Radiology, Nara Medical University, Kashihara, Japan, ²Gynecology, Nara Medical University, Kashihara, Japan, ³Siemens AG, Erlangen, Germany, ⁴Metallogenics Co., Ltd., Chiba, Japan

The measurement of R2 values to quantify the iron concentration in vivo and vitro.

Matthias C Schabel^1,2, Victoria H.J. Roberts³, Jamie O. Lo³, Antonio E. Frias⁴, and Chris D. Kroenke^1
1Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States, ²Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT, United States, ³Division of Diabetes, Obesity, and Metabolism, Oregon Health & Science University, Portland, OR, United States, ⁴Division of Obstetrics and Gynecology, Oregon Health & Science University, Portland, OR, United States

We describe a non-contrast method for assessing placental perfusion and fetal oxygenation status utilizing quantitative T2* mapping and a novel spatial model, and validate our method using DCE-MRI measurement in pregnant rhesus macaques.

Hiroko Tomita¹, Hiroshi Shinmoto¹, Shigeyoshi Soga¹, Kentaro Yamada¹, Tatsumi Kaji¹, Tomohiko Asano², and Koichi Oshio^3
1Radiology, National Defense Medical College, Saitama, Japan, ²Urology, National Defense Medical College, Saitama, Japan, ³Diagnostic Radiology, Keio University, School of Medicine, Tokyo, Japan

The purpose of this study was to investigate whether the parameters obtained from diffusion-weighted imaging using a gamma model could distinguish a Gleason 6 from a Gleason≥7 disease, and help to improve the prediction of insignificant prostate cancer in active surveillance candidates. Fifty-nine patients who underwent radical prostatectomy were included in this study. ROC analyses for predicting adverse pathologic outcomes in active surveillance candidates showed that the AUC of the parameters of the gamma model were from 0.81 to 0.88. DWI using the gamma model might help to improve the prediction of insignificant prostate cancer in active surveillance candidates.

Juan C. Camacho^1,2, Nima Kokabi¹, Peter A. Harri¹, Tracy E. Powell², and Sherif G. Nour^1,2
1Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, United States, ²Interventional MRI Program, Emory University Hospital, Atlanta, GA, United States

The study objective is to investigate Magnetic Resonance Spectroscopic Imaging (¹H-MRSI) in prostate lesions and to correlate the values with the results of MRI-guided prostate targeted sampling. A prospective cohort of patients presenting with persistently elevated or rising serum prostate specific antigen (PSA) and at least one lesion suspicious for prostate cancer that underwent MRI guided targeted biopsy was evaluated. Thirty-five consecutive patients were recruited presenting with 179 suspicious lesions.  ROC curve analysis demonstrates a poor performance of ¹H-MRSI as a non-invasive imaging biomarker.

Stephanie T. Chang¹, Shreyas S. Vasanawala¹, and Andreas M. Loening^1
1Radiology, Stanford University, Palo Alto, CA, United States

We retrospectively investigated whether administration of 1 mg of intramuscular (IM) glucagon to decrease bowel peristalsis prior to prostate MRI decreases motion artifact. Two blinded, independent readers reviewed MRI prostate studies of 25 and 26 patients who did and did not receive glucagon, respectively, for motion-related blurring of the prostate, bowel, and lymph nodes on a five-point Likert scale. No significant difference was observed in all categories. Although European Society of Uroradiology (ESUR) and American College of Radiology guidelines recommend using antiperistaltic agents for prostate MRI, our results suggest that IM glucagon may not be necessary.

Nelly Tan¹, Nazanin Asvadi¹, Amin Moshkar², Steven Raman², and Fabien Scalzo^3
1Radiology, UCLA, Los Angeles, CA, United States, ²UCLA, Los Angeles, CA, United States, ³Neurology, UCLA, Los Angeles, CA, United States

Our preliminary results suggest that using a trained machine learning algorithm (spectral regression model) to analyze multiparametric is highly accurate for automatically localizing prostate cancer.

Yuhao Dong¹, Wenbo Chen¹, Long Liang¹, Bin Zhang¹, and Shuixing Zhang^1
1Radiology, Department of Radiology, Guangdong Academy of Medical Sciences/Guangdong General Hospital, Guangzhou, Guangzhou, China, People's Republic of

Contrast induced acute kidney injury (CIAKI) is a common complication after the administration of contrast media.  The universally acknowledged mechanisms of CIAKI are the ischemia-mediated oxidative stress as well as the arteriolar vasoconstriction resulted from sustained contrast-induced, hypoxia in cortex and medulla. Our study aims to investigate noninvasive arterial spin-labeling (ASL) and blood oxygen level-dependent imaging (BOLD) sequences for measuring renal hemodynamics and oxygenation in different time points and different sites of kidney after contrast media administration. The results showed that ASL combining BOLD can further identify the primary cause of the decrease of renal oxygenation in CIAKI, which provides means for noninvasive monitoring renal function during the first 4 days of CIAKI in clinical routine work.

Xinchun Li¹, Qi Wang¹, Yingjie Mei², Jiaxi Yu¹, Qiao Zou¹, Yingshi Deng¹, and Yudong Yu^1
1Department of Radiology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China, People's Republic of, ²Philips Healthcare, Guangzhou, China, People's Republic of

The differential diagnosis of benign and malignant focal lesions of the lung is a hot and difficult problem in daily chest imaging. The purpose of our study was to evaluate the potential of intravoxel incoherent motion (IVIM)–derived parameters as well as apparent diffusion coefficient (ADC) in differentiating solitary pulmonary lesions.  The results demonstrate that IVIM-DWI could be more helpful for distinguishing malignant from benign lesions in lung. D has the best diagnostic efficiency.

Frank Wolfram¹, Thomas Lesser¹, Harald Schubert², Joachim Böttcher³, Jürgen R Reichenbach⁴, and Daniel Güllmar^4
1Department of Thoracic and Vascular Surgery, SRH Wald-Klinikum Gera, Teaching Hospital of Friedrich Schiller University of Jena, Gera, Germany, ²Institute of Laboratory Animal Sciences and Welfare, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ³Institute of Diagnostic and Interventional Radiology, SRH Wald-Klinikum Gera, Teaching Hospital of Friedrich Schiller University of Jena, Gera, Germany,⁴Medical Physics Group / IDIR, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany

MR imaging of ventilated lung is a challenging task. The low proton density with extremely short T2* and local field inhomogeneities on tissue-air interfaces are sub-optimal for MRI. Unilateral lung flooding replaces air content of one lung wing with saline. This experimental method enables sonographic guidance as well as therapeutic ultrasound ablation. The untoward properties of lung might change to ideal conditions with a homogen and high proton density after flooding. The aim of the study was to investigate the feasibility of in-vivo unilateral lung flooding in MR environment and to evaluate the MR imaging capabilities of flooded lung in a large animal model.

Masaya Takahashi¹, Keisuke Ishimatsu¹, Shanrong Zhang¹, Hua Lu², and Connie C.W. Hsia^2
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States, ²Pulmonary and Critical Care Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States

The purpose of this study was to investigate the ability of in vivo ultra-short echo time (UTE)-MRI for assessment of pulmonary microstructure and functions of ventilation-perfusion in an animal model of pulmonary fibrosis in comparison with high-resolution MRI, physiological global measures and histomorphology.

Marta Tibiletti¹, Dominik Berthel², Michael Neumaier³, Dorothee Schüler², Detlef Stiller³, and Volker Rasche^1,4
1Core Facility Small Animal MRI, Ulm University, Ulm, Germany, ²Rapid Biomedical GmbH, Rimpar, Germany, ³Target Discovery Research, In-vivo imaging laboratory, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany, ⁴Department of Internal Medicine II, Ulm University, Ulm, Germany

Lung imaging with MRI is challenging, due to the low proton density in the tissue, short T2* values due to multiple air-tissue interfaces, and respiratory and cardiac motion. A major step for providing sufficient signal to noise ratio (SNR) is the availability of dedicated coils optimized for the specific application. In this work, we present a 4-channel mouse phased-array coil optimized for the thoracic anatomy of mice. Depending on the field-of-view an average two- to threefold gain in SNR was observed in direct comparison to a conventional transmitt/receive quadrature volume coil at 11.7 T.

Neville D Gai¹, Ashkan A Malayeri¹, and David A Bluemke^1
1Radiology & Imaging Sciences, NIH, Bethesda, MD, United States

Effective imaging of short T2 species requires efficient suppression of longer T2 tisues to maximize short T2 contrast and dynamic range. While inversion with segmented k-space acquisition in Cartesian schemes is straightforward, inversion with segmented k-space UTE radial acquisition offers some challenges since the center of k-space is sampled with each acquisition resulting in magnetization modulation related artifacts. Here we perform 3D inversion recovery dual-echo UTE imaging of lung parenchyma using a reordered k-space radial scheme to perform artifact free high contrast imaging of native lung parenchyma.

Ilias Tsiflikas¹, Matthias Teufel¹, Sabrina Fleischer¹, Dominik Hartl², Konstantin Nikolaou¹, and Juergen F Schaefer^1
1Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tübingen, Germany, ²Pediatrics I - CF Center, University Hospital of Tuebingen, Tübingen, Germany

The study successfully evaluated a new developed CF-specific MRI score. Our results show that the MRI-Score can predict the loss of pulmonary function. Thus, our findings may help that MRI can serve as a novel predictive marker for loss of lung function in CF and thereby help to tailor individualized monitoring and treatment strategies.

Ravi Teja Seethamraju¹, Noreen Dunham², Donna Oka², Aida Faria², and Ritu Randhawa Gill^2
1MR R&D, Siemens Healthcare, Boston, MA, United States, ²Radiology, Brigham and Women's Hospital, Boston, MA, United States

We demonstrate that free breathing multi-parametric quantitative assessment of mesothelioma with MRI is feasible. DCE imaging of the thorax with 3D Radial stack of stairs gradient echo (radial VIBE) sequence can be acquired while free breathing and the resulting pharmacokinetic maps are of higher diagnostic value than current standard of 2D or 3D FLASH acquisitions without the need for co-registration. Similarly DWI with readout segmented EPI (RESOLVE) provides similar diagnostic value with a free breathing acquisition. These two biomarkers help improve the evaluation of tumor in mesothelioma patients.

Grzegorz Bauman^1,2 and Oliver Bieri^1,2
1Radiological Physics, University Hospital of Basel, Basel, Switzerland, ²Department of Biomedical Engineering, University of Basel, Basel, Switzerland

In the contemporary Fourier decomposition lung MRI, time-resolved registered 2D image series are Fourier transformed to identify in a power spectrum the underlying respiratory and cardiac frequencies. Subsequently, the amplitudes corresponding to the respiratory and cardiac motion are extracted voxel-wise to eventually produce ventilation and perfusion images. However, the analysis of truncated oscillatory signals and the peak search in the Fourier spectrum is usually very unstable and inaccurate. Here, we propose to use a robust and fully-automated method of signal analysis using a matrix pencil decomposition in combination with a linear least squares analysis for improved quantitative pulmonary function assessment.

Yueh Lee¹, Esther Akinnagbe-Zusterzeel¹, Jennifer Goralski¹, Scott Donaldson¹, Hongyu An², H. Cecil Charles³, and Richard Boucher^1
1The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, ²Washinton University, St. Louis, MO, United States, ³Duke University, Durham, NC, United States

19F MRI Ventilation imaging of cystic fibrosis patients demonstrates the disease heterogeneity using a straightforward dynamic protocol.

Konstantinos Zeimpekis^1,2, Klaas Pruessmann², Florian Wiesinger³, Patrick Veit-Haibach¹, and Gaspar Delso^4
1Nuclear Medicine, University Hospital Zurich, Zurich, Switzerland, ²Information Technology and Electrical Engineering, ETHZ, Zurich, Switzerland, ³GE Global Research, Munich, Germany, ⁴GE Healthcare, Waukesha, WI, United States

This study is about a first attempt to use CG-SENSE parallel reconstruction for non-cartesian 3D Ultra-short Echo Time Cones sequence for lung imaging. Primary goal is to test under-sampled data that reduce the scan time effectively to one quarter of the fully sampled acquisition and check if the reconstruction manages to capture lung density signal to be used for accurate PET Attenuation Correction on a PET/MRI since conventional sequences that are currently used do not capture any. We test also the possibility for high resolution lung imaging from the undersampled data reconstructed with CG-SENSE algorithm.

Fumin Guo¹, Khadija Sheikh¹, Rachel Eddy¹, Dante PI Capaldi¹, David G McCormack², Aaron Fenster¹, and Grace Parraga^1
1Robarts Research Institute, The University of Western Ontario, London, ON, Canada, ²Department of Medicine, The University of Western Ontario, London, ON, Canada

Clinical translation of hyperpolarized ¹²⁹Xe MRI for large-scale and multi-centre applications requires image analysis tools that can provide clinically-acceptable measurements of pulmonary information. Here we proposed a pipeline that consists of ¹H-¹²⁹Xe registration, segmentation and ventilation defects generation for regional and quantitative evaluation of ¹²⁹Xe ventilation. ¹H-¹²⁹Xe registration was performed using a state-of-art registration approach. ¹H MRI segmentation was performed using primal-dual analysis methods and modern convex optimization techniques with incorporation of region information from ¹²⁹Xe MRI. We applied the pipeline across a range of pulmonary abnormalities and this computationally efficient pipeline demonstrated high agreement with reference standard, suggesting its suitability for efficient clinical workflows.

Hongchen Wang¹, Georges Willoquet¹, Catherine Sebrié¹, Sébastien Judé², Anne Maurin², Rose-Marie Dubuisson¹, Luc Darrasse¹, Geneviève Guillot¹, Ludovic de Rochefort¹, and Xavier Maître^1
1Imagerie par Résonance Magnétique Médicale et Multi-Modalités (UMR8081) IR4M, CNRS, Univ. Paris-Sud, Orsay, France, ²Centre de Recherches Biologiques, CERB, Baugy, France

Asthma is the most common chronic respiratory disease treated with inhaled therapy. However, aerosol deposition patterns are complex and imaging methods are needed to improve delivery efficiency. 3D UTE-MRI combined with aerosolized Gd-DOTA had been formerly applied onto spontaneous nose-only-breathing animals. Here, a mechanical administration system was developed to ventilate and nebulize rats. Resulting aerosol distribution and kinetics were compared with free-breathing in healthy and asthmatic animals.

Aiming Lu¹, Xiangzhi Zhou¹, Mitsue Miyazaki¹, Masao Yui², Masaaki Umeda², and Yoshiharu Ohno^3,4
1Toshiba Medical Research Inst., Vernon Hills, IL, United States, ²Toshiba Medical System Corp, Otawara, Japan, ³Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Japan, ⁴Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan

T2* mapping with a single-exponential model have been demonstrated to be useful in accessing pulmonary functional loss.  However, the model does not fully explain the signal evolution at longer TEs. We propose to improve the T2* characterization in the lung parenchyma with a bi-exponential model. Using a 3D multi-echo radial sequence, our results demonstrated that short T2* values and the volume fractions of the two compartments could be obtained on a clinical 3T scanner. In addition to the improved accuracy of the short T2* measurement, the added fraction values could also potentially be used as biomarkers.

Daniel Alamidi¹, Simon Kindvall², Penny Hubbard Cristinacce³, Deirdre McGrath³, Simon Young⁴, Josephine Naish³, John Waterton³, Per Wollmer⁵, Sandra Diaz⁵, Marita Olsson⁶, Paul Hockings^7,8, Kerstin Lagerstrand¹, Geoffrey Parker^3,9, and Lars E Olsson^2
1Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden, ²Department of Medical Physics, Lund University, Translational Sciences, Malmö, Sweden, ³Centre for Imaging Sciences and Biomedical Imaging Institute, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom, ⁴AstraZeneca R&D, Alderley Park, United Kingdom, ⁵Department of Translational Medicine, Lund University, Malmö, Sweden, ⁶AstraZeneca R&D, Mölndal, Sweden, ⁷Medtech West, Chalmers University of Technology, Gothenburg, Sweden,⁸Antaros Medical, BioVenture Hub, Mölndal, Sweden, ⁹Bioxydyn Ltd, Manchester, United Kingdom

Tobacco smoking is the primary cause of COPD. MRI may improve the characterization of COPD where T1 of the lungs is a potential biomarker. We investigated whether smoking affects lung T1 in individuals with no known lung disease. Lung T1 measurements were performed in asymptomatic current and never smokers. T1 was shortened with age and an indication of shortened T1 in smokers was observed that most likely reflects early signs of smoking-induced lung pathology. Our results may be of utility to power future prospective studies with larger cohorts and improved regional analysis. 

Daniel Güllmar¹, Georg Hille², Martin Krämer¹, Karl-Heinz Herrmann¹, Jürgen R Reichenbach¹, and Jens Haueisen^2
1Medical Physics Group / IDIR, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ²Institute of Biomedical Engineering and Informatics, Faculty of Computer Science and Automation, Technical University Ilmenau, Ilmenau, Germany

The aim of the study was to acquire 3D radially sampled k-space data of a human torso without breath hold and prospective cardiac triggering. Respiration and cardiac pulsation were continuously recorded simultaneously with MR imaging over a time frame of 1 h. Retrospective data motion triggering was used to reconstruct 8 up to 10 different respiration phases and 12 up to 20 different cardiac cycle phases, resulting in 96 up to 200 different phase combinations. Image quality was evaluated based on SNR, CNR and under sampling artifacts.

Lukas Reinhold Buschle¹, Felix Tobias Kurz^1,2, Thomas Kampf³, Heinz-Peter Schlemmer¹, and Christian Herbert Ziener^1
1E010 Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ²Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany, ³Department of Experimental Physics 5, University of Würzburg, Würzburg, Germany

We analyze the local line shape in human lung tissue in dependence of the underlying microscopic tissue parameters such as diffusion coefficient, alveolar size and susceptibility difference. The interplay between susceptibility- and diffusion-mediated effects is discussed in several dephasing regimes. In vivo measurements for human lung tissue show an excellent agreement with simulations of the dephasing process. This allows an improved quantitative diagnosis of early pulmonary fibrosis and emphysema.

Lukas Reinhold Buschle¹, Felix Tobias Kurz^1,2, Thomas Kampf³, Heinz-Peter Schlemmer¹, and Christian Herbert Ziener^1
1E010 Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ²Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany, ³Department of Experimental Physics 5, University of Würzburg, Würzburg, Germany

In lung tissue, the susceptibility difference between air-filled alveoli and surrounding tissue causes a strong dephasing of spin-bearing particles. The particles experience an averaged magnetic field due to diffusion effects. Thus, the dephasing process slows down. Both diffusion and susceptibility effects are described by the Bloch-Torrey equation that is solved for the local magnetization on the surface of alveoli. The analytical solution of the free induction decay is compared to in vivo measurements in human lung tissue.

Hong Wang¹, Xing Tang¹, Panli Zuo², Shun Qi¹, and Hong Yin^1
1Department of Radiology, Department of Radiology,Xijing Hospital, Xi'an, China, People's Republic of, ²Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, People's Republic of

MR imaging is limited by poor evaluation of lung parenchyma due to rapid single decay, low tissue portion density and substantial respiratory motion. In this study, we evaluate three different approaches of VIBE sequences in pulmonary lesions detection, which including a short-TE breath-hold VIBE, DIXON VIBE and a free-breathing Radial VIBE. We found Breath-hold short-TE VIBE and Dixon VIBE sequences have better performance in lesion detection than radial VIBE.

Ryotaro Kamei¹, Yuji Watanabe², Koji Sagiyama¹, Satoshi Kawanami², Atsushi Takemura³, Masami Yoneyama³, and Hiroshi Honda^1
1Department of Clinical Radiology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan, ²Department of Molecular Imaging and Diagnosis, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan, ³Healthcare, Philips Electronics Japan, Tokyo, Japan

Breath-hold black-blood magnetic resonance imaging of the lung provides promising results in focal lesion screening. Using peripheral pulse gating, we intended to improve the image quality obtained with previously reported methods. Black-blood fat-saturated T2-weighted images were acquired for healthy volunteers at various time points during the pulse cycle. The degree of attenuation of the intraluminal signals was quantified. The longest trigger delay, which corresponds to the systolic phase, provided superior black-blood effects and was considered optimal for signal acquisition. Thus, peripheral pulse gating enabled convenient and effective attenuation of the signals within pulmonary vessels.

Yoshiharu Ohno^1,2, Yuji Kishida², Shinichiro Seki², Hisanobu Koyama², Shigeru Ohyu³, Masao Yui³, Takeshi Yoshikawa^1,2, Katsusuke Kyotani⁴, and Kazuro Sugimura^2
1Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Japan, ²Radiology, Kobe University Graduate School of Medicine, Kobe, Japan, ³Toshiba Medical Systems Corporation, Otawara, Japan, ⁴Center for Radiology and Radiation Oncology, Kobe University Hospital, Kobe, Japan

    Quantification of perfusion parameter from dynamic CE-perfusion MRI at 3T system may be more difficult than that at 1.5T system, and contrast media concentration may have larger influence to measurement error of perfusion parameter on a 3T system.  We hypothesized that a bolus injection protocol with appropriately small contrast media volume can provide accurate pulmonary perfusion parameter on dynamic CE-perfusion MRI at a 3T system.  The purpose of this study was to determine the appropriate contrast media volume for quantitative assessment of dynamic CE-pulmonary MRI, when compared with dynamic CE-area-detector CT (ADCT) for quantitative evaluation of perfusion within whole lung.

Wingchi Edmund Kwok^1,2, Clement Ren³, Gloria Pryhuber⁴, Mitchell Chess¹, and Jason C. Woods^5
1Department of Imaging Sciences, University of Rochester, Rochester, NY, United States, ²Rochester Center for Brain Imaging, University of Rochester, Rochester, NY, United States, ³Department of Pediatrics, University of Rochester, Rochester, NY, United States, ⁴Departments of Pediatrics and Environmental Medicine, University of Rochester, Rochester, NY, United States, ⁵Departments of Pediatrics and Radiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States

Our purpose was to study the feasibility of high-resolution lung ultra-short TE imaging of young children at 3T without sedation and tackle potential challenges.  Two subjects aged 7 and 8 with mild cystic fibrosis were recruited.  They were supported by a child life specialist and the use of a mock magnet.  Siemens work-in-progress UTE and PETRA_D sequences were used for lung imaging.  The images depicted the lung parenchyma, airways and vessels, and revealed abnormalities such as bronchial wall thickening.  The techniques should be useful for the monitoring of lung development and evaluation of lung diseases in children.

Kai Ruppert^1,2, Kun Qing², Talissa A. Altes^2,3, and John P. Mugler III^2
1Cincinnati Children's Hospital, Cincinnati, OH, United States, ²University of Virginia, Charlottesville, VA, United States, ³University of Missouri, Columbia, MO, United States

Chemical Shift Saturation Recovery (CSSR) MR Spectroscopy is a method for monitoring the uptake of hyperpolarized xenon-129 (HXe) by lung parenchyma. The purpose of this study was to investigate the correlation between the alveolar surface-to-volume ratio (S/V) as assessed by CSSR spectroscopy and apparent diffusion coefficient measurements in subjects with chronic-obstructive pulmonary disease, healthy smokers and age-matched normals. Only for very short delay times (5 ms or less) a good correlation was established. Surprisingly, the best correlation, and presumably most accurate S/V value, was obtained by using just the red-blood cell peak at the shortest measured delay time of 3ms.

Steven Guan¹, Kun Qing¹, Talissa Altes¹, John Mugler III¹, Borna Mehrad¹, Michael Shim¹, Quan Chen¹, Paul Read¹, James Larner¹, Iulian Ruset^2,3, Grady Miller¹, James Brookeman¹, William Hersman^2,3, and Jaime Mata^1
1University of Virginia, Charlottesville, VA, United States, ²University of New Hampshire, Duhram, NH, United States, ³XeMed, Duhram, NH, United States

3D Single-Breath Chemical Shift Imaging (3D SB-CSI) is capable of non-invasively assessing regional lung ventilation and gas uptake/exchange within a single breath-hold, typically less than 13 seconds.  From this study, we present preliminary clinical results of 3D SB-CSI from healthy, cystic fibrosis (CF), interstitial lung disease (ILD), and lung cancer (LC) subjects at 1.5T and 3T. Having novel information on regional changes in ventilation and gas uptake/exchange allows for a better understanding of lung physiology, disease progression, and treatment efficacy.

Paul J.C. Hughes¹, Helen Marshall¹, Felix C. Horn¹, Guilhem J. Collier¹, and Jim M. Wild^1
1Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom

Automating image analysis is key to accelerate quantitative image metric calculation and increase consistency between observers. This work presents a custom-built software to calculate percentage lung ventilated volume (%VV) from hyperpolarised gas and ¹H MRI using spatial fuzzy c-means thresholding. The software developed reduced analysis time and user input resulting in significantly decreased interobserver variability when postprocessing image data.

Mu He¹, Scott H. Robertson², Jennifer M. Wang³, Craig Rackley⁴, H. Page McAdams⁵, and Bastiaan Driehuys^5
1Electrical and Computer Engineering Department, Duke University, Durham, NC, United States, ²Medical Physics Graduate Program, Duke University, Durham, NC, United States, ³School of Medicine, Duke University, Durham, NC, United States, ⁴Pulmonary, Allergy and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States, ⁵Radiology, Duke University Medical Center, Durham, NC, United States

The use of ¹²⁹Xe MRI to characterize ventilation has received little attention in IPF because these patients exhibit few ventilation defect regions (VDR) compared to those with other obstructive lung diseases. Here, we evaluate other aspects of the ventilation distribution by optimized linear binning. Ventilation distributions were quantified to provide not only VDR, but also low and high-intensity regions (LIR, HIR). We found that HIR was reduced by 3-fold in patients with late versus early stage disease, as measured by GAP IPF stage. Thus, loss of HIR may be a useful marker of disease progression in IPF.

Wolfgang Loew¹, Robert Thomen¹, Randy Giaquinto¹, Ron Pratt¹, Zackary Cleveland¹, Laura Walkup¹, Charles Dumoulin¹, and Jason Woods^1
1Imaging Research Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States

Hyperpolarized gas MRI of lungs requires homogeneous RF excitation and high SNR for proper spin-density mapping with low flip angles. A dual loop T/R ¹²⁹Xe coil was designed and constructed to provide flexibility for a wide range of patient sizes while maintaining high transmit/receive homogeneity for hyperpolarized ¹²⁹Xe imaging and therefore provide high-quality images for identifying and quantifying functional pulmonary deficiencies. Electromagnetic field simulations were used to analyze excitation profiles.

Wei Zha¹, Jeffery N Kammerman¹, David G Mummy², Alfonso Rodriguez¹, Robert V Cadman¹, Scott K Nagle^1,3,4, Ronald L Sorkness^4,5,6, and Sean B Fain^1,2,3
1Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ²Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, ³Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, ⁴Department of Pediatrics, University of Wisconsin-Madison, Madison, WI, United States, ⁵Medicine-Allergy, Pulmonary & Critical Care, University of Wisconsin-Madison, Madison, WI, United States, ⁶Pharmacy, University of Wisconsin-Madison, Madison, WI, United States

Seven cystic fibrosis (CF) and 69 asthma subjects with different severities of disease underwent hyperpolarized helium-3 MRI and multidetector computed tomography (MDCT). Lobar segmentation was performed on proton MRI by referencing corresponding MDCT. The lobar ventilation defect percent (VDP) was measured by adaptive K-means. Pairwise comparison showed that lobar VDP variation patterns were different in CF vs. asthma, although patterns were similar in severe vs. non-severe asthma. Disease-related lobar VDP variation patterns may provide a sensitive indicator for early detection and patterns of progression in obstructive lung disease.

Wei Zha¹, Stanley J Kruger¹, Robert V Cadman¹, Kevin M Johnson^1,2, Andrew D Hahn¹, Scott K Nagle^1,2,3, and Sean B Fain^1,2,4
1Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, ²Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, ³Department of Pediatrics, University of Wisconsin-Madison, Madison, WI, United States, ⁴Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States

Oxygen-enhanced MRI using 3D radial ultrashort echo time sequence (OE-MRI) is a promising alternative to evaluate ventilation and defects with wider accessibility and better affordability.  Eleven cystic fibrosis (CF) subjects with different severities of disease underwent OE-MRI and HP-MRI. The disease severity ranks on the percent signal enhancement map (PSE) derived from OE-MRI was compared to the whole lung ventilation defect percent (VDP) measured from HP-MRI as a reference standard using Spearman rank correlation. The moderate association between VDP and PSE suggest OE-MRI shows promise for differentiating disease severity in CF.

Megan Fennema¹, Sarah Svenningsen¹, Rachel Eddy¹, Del Leary², Geoffrey Maksym³, and Grace Parraga^1
1Robarts Research Institute, The University of Western Ontario, London, ON, Canada, ²Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States, ³School of Biomedical Engineering, Dalhousie University, Halifax, NS, Canada

In patients with asthma, MRI has provided evidence of ventilation-defects and heterogeneity.  The etiology of ventilation-heterogeneity is not well-understood, and neither is its relationship with clinically-relevant respiratory-system-impedance measurements.  We evaluated the potential relationships between MRI ventilation-defects and respiratory-system-impedance measured in vivo using oscillometry and in silico using a computational airway-tree-model, in subjects clinically diagnosed with asthma.  Both experiments suggested a significant relationship between MRI ventilation-defects and respiratory-system-reactance.  In vivoexperimental data presented here reinforced the validity of our computational airway-tree-model.  MRI-derived ventilation-defects in asthmatics can be explained by lung impedance, specifically reactance, measured experimentally and using a computational model.

Ziyi Wang¹, Scott Haile Robertson², Jennifer Wang³, Elianna Ada Bier², Mu He⁴, and Bastiaan Driehuys^1,2,5
1Biomedical Engineering, Duke University, Durham, NC, United States, ²Medical Physics Graduate Program, Duke University, Durham, NC, United States, ³School of Medicine, Duke University, Durham, NC, United States, ⁴Electrical and Computer Engineering, Duke University, Durham, NC, United States, ⁵Radiology, Duke University Medical Center, Durham, NC, United States

Hyperpolarized ¹²⁹Xe MRI exploits solubility and chemical shift to image regional alterations in gas exchange. These properties have been particularly promising for sensitive detection and monitoring of idiopathic pulmonary fibrosis (IPF). Here we seek to refine our analysis of regional gas exchange impairment by mapping the ¹²⁹Xe uptake in blood and barrier tissues relative to gas-phase signal intensity. This work shows that gas exchange impairment is dominated by increased ¹²⁹Xe uptake in barrier tissues. 

Wei Wang¹, Wei Li¹, Xueqian Shang¹, and Xiaoying Wang^1
1Peking University First Hospital, Beijing, China, People's Republic of

The study preliminary compared the ability of non-contrast-enhanced MRI and contrast-enhanced CT in detection, characterization and staging of esophageal cancer. Ten patients’ chest CT and MR images were subjectively evaluated. We found that MR was not inferior to CT, and showed superior capacity in detecting early unapparent cancer, delineating the tumor precisely and depicting perfect contrast of surrounding structures. Also MR was relatively safe than contrast-enhanced CT. MR may be a potential useful tool for evaluation esophageal cancer. 

Jiadi Xu¹, Vincent DeMarco², Supriya Pokkali ², Alvaro Ordonez², Mariah Klunk², Marie-France Penet³, Zaver Bhujwalla³, Peter van Zijl^1,3, and Sanjay Jain^2,4
1F. M. Kirby Center, kennedy Krieger Institute, Baltimore, MD, United States, ²Center for Infection and Inflammation Imaging Research, Center for Tuberculosis Research, Johns Hopkins University School of Medicine, Baltimore, MD, United States, ³Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States, ⁴Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, United States

A UTE-CEST scheme was developed to acquire CEST spectrum on M. Tuberculosis lesions in mouse lung. The scheme repeats a selective saturation pulse together with an appropriate mixing time; MRI images are acquired using the UTE technique during the mixing times. The UTE readout is able to suppress the respiratory motion artifacts commonly seen in lung MRI. The pattern of the MTRasym spectra in the TB lesion, which is dominated by protein signals, was used to assess lesion pH. 

Wiebke Neumann¹, Florian Lietzmann¹, Lothar R. Schad¹, and Frank G. Zöllner^1
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany

Anthropomorphic phantoms are an essential tool for the validation of image registration algorithms of multimodal data and are important for quantification experiments in ¹H and ²³Na MR imaging. A human thorax phantom was developed with insertable lung, liver, rib cage modules and tracking spheres. Evaluation regarding the tissue-mimicking characteristics with ¹H and ²³Na MR and CT imaging shows that the modules possess T₁, T₂ and HU values comparable to those of human tissues. This work presents an MR- and CT-compatible phantom which allows experimental studies for quantitative evaluation of deformable, multimodal image registration algorithms and realistic multi-nuclei MR imaging techniques.

Akihiko Kanki¹, Tsutomu Tamada¹, Ayumu Kido¹, Kazuya Yasokawa¹, Tomohiro Sato¹, Daigo Tanimoto¹, Minoru Hayashida¹, Akira Yamamoto¹, and Katsuyoshi Ito^1
1Radiology, Kawaski Medical school, Kurashiki, Japan

The purpose of our study was to clarify the relationship between transient severe motion in arterial phase imaging (TSMA) and changes in SpO2 after contrast media administration during gadoxetic acid-enhanced MRI or CT. As the results, the decrease in SpO2 in arterial phase compared with other phases was less than 1% in both contrast media. The incidence of TSMA was 0% in iodinated contrast media and was 8.2% in gadoxetic acid, respectively. Our study suggests that the cause of TSM in dynamic gadoxetic acid-enhanced MR imaging of the liver may be the ringing artifacts rather than the respiratory-related motion artifacts.  

Mamoru Takahashi¹, Yasuo Takehara², Kenji Fujisaki¹, Tomoyuki Okuaki ³, Yukiko Fukuma³, Norihiro Tooyama¹, Katsutoshi Ichijo¹, Tomoyasu Amano¹, and Harumi Sakahara^4
1Radiology, Seirei Mikatahara General Hospital, Hamamatsu, Japan, ²Hamamatsu University Hospital, Hamamatsu, Japan, ³Philips Electronics Japan, Ltd., Tokyo, Japan, ⁴Hamamatsu University School of Medicine, Hamamatsu, Japan

Using 3D dual echo UTE sequence, all cholesterol gallstones were able to be detected as positive signal in-vitro. Our study may indicate that UTE has an added value of depicting impacted stones or hepatolithiasis as positive signal. In initial clinical experiences, cholesterol gallstones were also successfully visualized as positive signal with UTE.

Yukihisa Takayama¹, Akihiro Nishie², Yoshiki Asayama², Kousei Ishigami², Yasuhiro Ushijima², Daisuke Okamoto², Nobuhiro Fujita², Masami Yoneyama³, and Hiroshi Honda^2
1Department of Radiology Informatics and Network, Kyushu University, Graduate School of Medical Sciences, Fukuoka, Japan, ²Department of Clinical Radiology, Kyushu University, Graduate School of Medical Sciences, Fukuoka, Japan, ³Philips Electronics Japan, Tokyo, Japan

A non-balanced spin-echo steady-state free precession (SSFP) sequence is a variant of the gradient echo (GRE) sequence. It provides T2-weighted contrast because it generates the spin echo. It also has high sensitivity to contrast agents’ T1-shortening effects. After the optimization of MR parameter settings, the non-balanced spin-echo SSFP sequence in the hepatobiliary phase (HBP) of Gd-EOB-MRI is useful for differential diagnoses of liver hemangiomas and metastatic liver tumors, based on the interpretation of the lesion signal intensity. Here we assessed the diagnostic performance of the non-balanced spin-echo SSFP sequence in the HBP of Gd-EOB-MRI.

Johannes Budjan¹, Philipp Riffel¹, Melissa Ong¹, Stefan O Schoenberg¹, Ulrike I Attenberger¹, and Daniel Hausmann^1
1Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Mannheim, Germany

In patients with breath-holding difficulties, breathing artifacts can result in dramatically reduced image quality during hepatobiliary phase imaging. Rapid Cartesian as well as radial acquisition techniques are approaches to minimize these artifacts. In 21 patients, both techniques were used and compared regarding image quality and lesion conspicuity. For most patients, a high flip angle Cartesian sequence with short breath-hold interval was feasible and resulted in superior overall image quality. Radial techniques proved to be a valuable option for the few patients who were unable to hold even short breath-hold intervals.

Yajing Zhang¹, Zhen Jiang², Weiping Liu¹, Feng Huang¹, Ming Yang¹, Allan Jin¹, and Ping Yang^1
1Philips Healthcare, Suzhou, China, People's Republic of, ²2nd affiliated Hospital of Soochow University, Suzhou, China, People's Republic of

Quantification of dynamic contrast enhanced MRI (DCE-MRI) is often hindered by motion during imaging. Multiple sources of motion require for a non-rigid 3D registration to align dynamic images. This study provided a rapid 3D non-rigid registration tool for DCE liver registration by optimizing the scheme of image matching. The results show that the dynamic images were well aligned in terms of whole liver area and the portal vein area. Meanwhile, the intensity plot demonstrated better representation from the registered images. Computation time of registration was about one minute for the entire scan, making it possible for clinical routine analysis.

Taiyou Leopoldo Harada¹, Kazuhiro Saito¹, Yoichi Araki¹, Jun Matsubayashi², Toshitaka Nagao², and Koichi Tokuuye^1
1Radiology, Tokyo Medical University Hospital, Shinjuku-ku, Japan, ²Pathology, Tokyo Medical University Hospital, Shinjuku-ku, Japan

This study is to evaluate which is favorable surrogate marker to predict the liver fibrosis, DWI or quantitative enhancement ratio measured at hepatobiliary phase on Gd-EOB-DTPA enhanced-MRI. Eighty-three patients with 99 lesions were enrolled. ADC was measured at a distance of 5-10 mm from the tumor. Liver-to-muscle ratio (LMR), liver-to-spleen ratio (LSR) and contrast enhancement index (CEI) were calculated. ADC showed no significant difference among fibrosis grades. LMR and CEI showed significant differences between high stage and low stage fibrosis group (p<0.01 and p=0.04). In conclusion, LMR was best surrogate parameters to distinguish high stage from low stage fibrosis.

Takeshi Yoshikawa¹, Katsusuke Kyotani², Yoshiharu Ohno¹, Shinichiro Seki³, Hisanobu Koyama³, Kouya Nishiyama², and Kazuro Sugimura^3
1Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Japan, ²Radiology, Kobe University Hospital, Kobe, Japan, ³Radiology, Kobe University Graduate School of Medicine, Kobe, Japan

We introduced new assessment method of liver hemodynamics using 4D-PCA and new flow analytic technique including wall shear stresses. We found 4D-PCA can be clinically used as a non-contrast angiography and our approach enables detailed hemodynamic assessment for each hepatic vessel.

Kristina Imeen Ringe¹, Christian von Falck¹, Hans-Juergen Raatschen¹, Frank Wacker¹, and Jan Bernd Hinrichs^1
1Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany

The purpose of our present study was to evaluate the incidence of TSM at gadoxetate disodium-enhanced MRI using different contrast application protocols, i.e. by variation of contrast injection rate, dose and supplemental nasal oxygen application. In addition to quantitative SNR measurements, motion artifacts and arterial phase image quality were compared. The overall incidence of TSM in our study population was 11.5%, and neither variation of contrast application parameter was able to significantly reduce the occurrence of these artifacts.

Hongxia Lei^1,2, Ana Francisca Soares³, and Rolf Gruetter^3,4
1Animal Imaging and Technology CIBM-AIT, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, ²University of Geneva, Geneva, Switzerland, ³Laboratory of functional and metabolic imaging LIFMET, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland, ⁴University of Lausanne, Lausanne, Switzerland

Abnormal vascular connections within the liver, such as congenital portosystemic shunts occur sporadically in widely used strain of laboratory mice, i.e. the C57BL/6J strain. We showed that with the respiration gating, MR angiography yields vascular structures of mouse liver with excellent quality and thus allowing diagnosing such abnormality non-invasively.

Marek Chmelik^1,2, Martin Gajdošík^1,2, Emina Halilbasic³, Ladislav Valkovic^1,4, Wolfgang Bogner¹, Stephan Gruber¹, Michael Trauner³, Siegfried Trattnig^1,2, and Martin Krššák^1,2,3
1High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, ²Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria,³Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria, ⁴OCMR, RDM Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom

The purpose of this study was to acquire ³¹P-3D-MRSI data with extended coverage of the hepatobiliary system using a 8-channel receive array at 3T. This protocol enables prospective phosphatidylcholine (PtdC) assessment in the gallbladder. As the bile amount in the gallbladder changes according to dietary condition, the protocol was tested pre-/post-meal. After overnight fasting all volunteers had gallbladder filled with the bile visible in both ³¹P-MRSI data as strong PtdC signal at 2ppm and in T₂ weighted images as hyperintense region. A reduced PtdC signal and volume of the gallbladder were visible after digestion of the high fat meal.

Adrienne Lee¹, Benjamin Rowland¹, Huijun Liao¹, Ana Maria Grizales², Allison Goldfine², and Alexander Lin^1
1Center for Clinical Spectroscopy, Brigham and Women’s Hospital, Boston, MA, United States, ²Research Division, Joslin Diabetes Center, Boston, MA, United States

Proton magnetic resonance spectroscopy (MRS) is an accurate, noninvasive method used to monitor intrahepatic triglyceride (IHTG) levels in four patients undergoing betaine treatment for nonalcoholic fatty liver disease (NAFLD).  Comparison of results in two of the patients with lower IHTG levels at baseline showed a decrease or improvement after betaine supplementation. However, two subjects with baseline elevated levels of IHTG did not show an improvement and in fact showed higher IHTG levels.  Reproducibility of primary lipid vs secondary lipid measurements were also obtained and demonstrated high and low reproducibility, respectively.

Jin Shang¹, Qi-yong Guo¹, Bing Yu¹, Yu Shi¹, Kai-ning Shi², and Ying Liu^1
1Department of Radiology,Shengjing Hospital of China Medical University, Shenyang, China, People's Republic of, ²Imaging Systems Clinical Science,Philips Healthcare, Beijing, China, People's Republic of

At present, traditional fat suppression still brings heavy chemical-shift artifacts in diffusion weighted imaging (DWI) in abdomen 3T magnetic resonance scan. The purpose of this paper is to study the effect of two different DWI sequences for fat suppression on normal pancreas. From the above research, it can be concluded that DWI with LIPO may serve as an more effective method on improving the image quality of pancreas at 3.0T MR.

Shivani Pahwa¹, Hao Liu², Yong Chen³, Sara Dastmalchian¹, Ziang Lu¹, Chaitra Badve⁴, Alice Yu¹, Joshua Batesole⁴, Hamid Chalian⁴, Katherine Wright¹, Shengxiang Rao⁵, Caixia Fu⁶, Ignacio Vallines⁷, Dean Nakamoto⁸, Mark Griswold⁹, Nicole Seiberlich¹⁰, Zeng Mengsu¹¹, and Vikas Gulani^12
1Radiology, Case Western Reserve University, Cleveland, OH, United States, ²Zhongshan Hospital, Fudan University, Shanghai, China, People's Republic of, ³Case Western Reserve University, Cleveland, OH, United States, ⁴Radiology, University Hospitals, Cleveland, OH, United States, ⁵Zhongshan Hospital< Fudan University, Shanghai, China, People's Republic of, ⁶Siemens, Shanghai, China, People's Republic of, ⁷Siemens Healthcare, Shanghai, China, People's Republic of, ⁸Radiology, Case Western Reserve University and University Hospitals, Cleveland, OH, United States, ⁹Radiology and Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ¹⁰Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ¹¹Radiology, Zhongshan Hospital, Fudan University, Shanghai, China, People's Republic of, ¹²Radiology, University Hospitals Case Medical Center, Cleveland, OH, United States

Breath holds and lack of a quantitative dimension are the two major challenges in liver MR imaging.  Free breathing, perfusion sequences created in academic institutions in the developed world have not been tested in busy and overloaded radiology practices worldwide. We evaluated free-breathing, 3D Through-time Spiral GRAPPA perfusion technique at two different field strengths in the US and China. We found that the perfusion parameters obtained for two most common hepatic lesions ie hepatocellular carcinoma and metastases were remarkably consistent across sites, though statistically different according to pathology. 

Nader S. Metwalli^1,2, Ronald Ouwerkerk¹, Ahmed M. Gharib¹, and Khaled Z. Abd-Elmoniem^1
1Biomedical and Metabolic Imaging Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States, ²Biomedical Engineering Department, Cairo University, Giza, Egypt

Liver fibrosis occurs as a result of long standing chronic liver disease of various etiologies. Reversibility of liver fibrosis has generated considerable attention lately. Early detection of increased liver stiffness would potentially guide towards more effective treatments. Our accelerated acquisition of liver tagging MRI to assess liver mechanics allows larger volumetric coverage and a substantially shorter acquisition time (≈ 80% reduction of total acquisition) than conventional tagging whilst delivering comparable results.

Ramin Jafari¹, Martin R. Prince², Yi Wang², Shalini Chhabra³, Jonathan P. Dyke², and Pascal Spincemaille^2
1Department of Biomedical Engineering, Cornell University, Ithaca, NY, United States, ²Department of Radiology, Weill Cornell Medical College, New York, NY, United States, ³Nuclear Medicine, Weill Cornell Medical College, New York, NY, United States

Tissue Analysis

Suresh Anand Sadananthan¹, Navin Michael¹, Mya Thway Tint², Kuan Jin Lee³, Jay Jay Thaung Zaw², Khin Thu Zar Hlaing², Pang Wei Wei², Lynette Pei-Chi Shek⁴, Yap Kok Peng Fabian^5,6, Peter D. Gluckman^1,7, Keith M. Godfrey⁸, Yap Seng Chong^1,2, Melvin Khee-Shing Leow^9,10, Yung Seng Lee^1,4, Christiani Jeyakumar Henry⁹, Marielle Valerie Fortier¹¹, and S. Sendhil Velan^1,3
1Singapore Institute for Clinical Sciences, A*STAR, Singapore, ²Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, ³Singapore BioImaging Consortium, A*STAR, Singapore, ⁴Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, ⁵Department of Paediatric Endocrinology, KK Women’s and Children’s Hospital, Singapore, ⁶Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, ⁷Liggins Institute, University of Auckland, Auckland, New Zealand, ⁸MRC Lifecourse Epidemiology Unit & NIHR Southampton Biomedical Research Centre, University of Southampton & University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom, ⁹Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, A*STAR, Singapore, ¹⁰Department of Endocrinology, Tan Tock Seng Hospital, Singapore, ¹¹Department of Diagnostic and Interventional Imaging, KK Women’s and Children’s Hospital, Singapore

Longitudinal assessment of abdominal fat compartments in children can help delineate some of the early risk factors that can predispose an individual to high abdominal adiposity and insulin resistance. While accurate determination of abdominal fat can be achieved using CT or MRI, it is often not performed in large cohort studies involving young children due to radiation exposure, high costs or poor compliance with scan procedures. The goal of this work is to develop and validate predictive equations for abdominal fat compartments from anthropometric values with MRI-based abdominal fat volumes as reference in multi-ethnic cohort of 4.5 year-old Asian children.

Amir Moussavi^1,2, Susanne Rauh³, Kristin Koetz¹, Stefan Krautwald⁴, and Susann Boretius^1,2
1Funktionelle Bildgebung, Deutsches Primatenzentrum, Göttingen, Germany, ²Molecular Imaging North Competence Center, University Medical Center Schleswig-Holstein, Kiel, Germany, ³Department of Physics, Christian-Albrechts-University, Kiel, Germany, ⁴Department for Nephrology and Hypertension, University Medical Center Schleswig-Holstein, Kiel, Germany

Obesity is currently one of the most relevant health problems and analyzing body-fat-distribution is of great importance in obesity research. Using radial encoded spoiled FLASH, data sets covering the entire abdomen of mice were obtained at 3 different echo times without any gaiting technique. Fat and water signals were separated using the three-point Dixon method and using IDEAL in comparison. Based on this, the visceral and subcutaneous fat compartments were successfully segmented.

Kyu-Ho Song¹, Song-I Lim¹, Chi-Hyeon Yoo¹, and Bo-Young Choe^1
1Department of Biomedical Engineering, and Research Institute of Biomedical Engineering, The Catholic University of Korea College of Medicine, Seoul, Seoul, Korea, Republic of

The objective of this study is to compare lipid contents using the point-resolved spectroscopy and stimulated echo acquisition mode sequences to assess lipid resonances in the liver, using in vivo high-resolution spectra at 9.4 T.

Clemens Diwoky¹, Renate Schreiber¹, and Rudolf Zechner^1
1Institute of Molecular Biosciences, University of Graz, Graz, Austria

Interscapular brown adipose tissue plays an important role in the maintenance of core body temperature of small mammals through a process known as nonshivering thermogenesis. A dense vascular system delivers oxygen for the thermogenesis and is needed for the transport of produced heat from iBAT towards thoracic and abdominal areas. Therefore iBAT blood perfusion is an important parameter for analyzing iBAT activation and function.

The FAIR ASL protocol developed within this study accounts for the high lipid content in the interscapular area as well as the structure of the iBAT vascular system.

iBAT blood perfusion was determined in wildtype mice and the used protocol is justified based on perfusion numbers determined from skeletal muscle.