Ayhan Gursan¹, Martijn Froeling¹, Arjan D. Hendriks¹, Dimitri Welting¹, Dennis W.J. Klomp¹, and Jeanine J. Prompers^1
1Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands

DMI in combination with oral administration of deuterated glucose could potentially be used to investigate glycolytic and oxidative glucose metabolism in skeletal muscle non-invasively. However, skeletal muscle is a tissue with a high degree of spatial organization. In this study, we investigated the effect of anisotropic motional averaging on 7T deuterium spectra of the lower leg muscles. We observed quadrupole moment splittings of the natural abundance HDO signal and showed that the size of these splittings depends on the angle between muscle fibers and the main magnetic field B₀.

Jimin Ren^1,2, Craig R Malloy^1,2, and Dean Sherry^1,2
1Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States, ²Department of Radiology, UT Southwestern Medical Center, Dallas, TX, United States

Despite its very small size and highly structural symmetry, the brain inorganic phosphate (Pi) signal is twice broader in linewidth or even splitting as compared to phosphocreatine signal by 31P-MRS at 7T. This puzzling phenomenon is attributed to spacial pH heterogeneity and rapid Pi diffusion between different cellular compartments, which likely prevails over other potential factors such as chemical exchange. Importantly, the Pi lineshape deconvolution by a two-component approach may provide a novel way to measure the distribution of neurons and astrocytes in brain if the assignment confirmed. Therefore this simple method may hold great promise to study neurodegenerative diseases.

Ayhan Gursan¹, Arjan D. Hendriks¹, Dimitri Welting¹, Dennis W.J. Klomp¹, and Jeanine J. Prompers^1
1Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands

Deuterium metabolic imaging (DMI) is an emerging method to assess metabolism in vivo. In this study, we applied dynamic 3D DMI with oral administration of deuterated glucose to investigate the dynamics of hepatic glucose uptake and metabolism at 7T. After glucose intake, the signal from deuterated glucose logarithmically increased in the liver and plateaued around 100 min, after which it decreased again, as a result of its conversion through glycolysis, oxidative metabolism and, probably the largest part, glycogen synthesis. DMI will be a valuable tool to study disturbances of liver metabolism in metabolic diseases.

Jia Xu¹, Rolf F. Schulte², William R. Kearney¹, and Vincent A. Magnotta^1,3,4
1Radiology, University of Iowa, Iowa City, IA, United States, ²GE Global Research, Munich, Germany, ³Psychiatry, University of Iowa, Iowa City, IA, United States, ⁴Biomedical Engineering, University of Iowa, Iowa City, IA, United States

The test-retest repeatability of ATP and PCr concentrations in the human brain was measured with a non-localized, quantitative ³¹P MRS protocol. The performance of several automated MRS quantification methods that require little or no human intervention were evaluated. We found that the peak integration by simple summation of the magnitude spectrum is the most sensitive and robust to detect small ATP concentration changes. The excellent test-retest repeatability enables ATP concentration to be studied instead of using them as internal reference. This is important in diseases such as those that impair mitochondrial function resulting in impaired oxidative phosphorylation.

Zahra Shams¹, Evita C. Wiegers¹, Wybe J.M. van der Kemp¹, Dennis W.J. Klomp¹, and Jannie P. Wijnen^1
1Department of radiology, University Medical Center Utrecht, Utrecht, Netherlands

The ratio of phosphomonoesters (PME) and phosphodiesters (PDE) is potentially an important biomarker of cancer in the body, which can be measured by ³¹P MR spectroscopy. Here, we introduce a dual band pulse of low B₁⁺ amplitude for specific refocusing of these metabolite signals. This can be an alternative solution to the high power demanding adiabatic refocusing pulses used for ³¹P MRS in the body, upon using a multi-echo sequence.

Karthik Chary¹, Franck Mauconduit², Fiona Smith¹, Marie Chupin³, Emmanuelle Gourieux^2,3, Laura Pelizzari⁴, Karen Kettless⁵, Kristoffer Brendstrup-Brix⁶, Eva Mezger⁷, Daniel Keeser⁷, Olaf Dietrich⁸, Tim Wesemann⁹, Philipp Ritter¹⁰, Annett Werner⁹, Letizia Squarcina¹¹, Paolo Brambilla^11,12, Frank Bellivier¹³, Fawzi Boumezbeur², David Cousins^1,14, and Pete Thelwall^1
1Translational and Clinical Research Institute, Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, United Kingdom, ²NeuroSpin, CEA, CNRS, Paris-Saclay University, Gif-sur-Yvette, France, ³CATI, Institut du Cerveau et de la Moëlle Epinière, Paris, France, ⁴IRCCS, Fondazione Don Carlo Gnocchi ONLUS, Milan, Italy, ⁵Siemens Healthcare A/S & Siemens Healthcare GmbH, Copenhagen, Denmark, ⁶Neurobiology Research Unit (NRU) at Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark, ⁷Department of Psychiatry and Psychotherapy, University Hospital, LMU University, Munich, Germany, ⁸Department of Radiology, University Hospital, LMU Munich, Munich, Germany, ⁹Institute and Clinic of Diagnostic and Interventional Neuroradiology, University Hospital, Carl Gustav Carus, Dresden, Germany, ¹⁰Department of Psychiatry, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany, ¹¹Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy, ¹²Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy, ¹³INSERM UMRS-1144, AP-HP, Saint-Louis - Lariboisière – F. Widal Hospitals, Paris, France, ¹⁴Regional Affective Disorders Service, Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust, Newcastle Upon Tyne, United Kingdom

⁷Li-MRI is a unique technique to trace the brain lithium distribution, which may predict treatment response in bipolar disorder. The signal-to-noise ratio in balanced steady state free precession acquisition protocols (bSSFP) for ⁷Li-MRI can be efficiently optimized using physiologically representative phantoms. We sought to implement and validate a bSSFP protocol to maximize ⁷Li signal amplitude using theoretical modelling and phantom acquisitions, further validating the sequence across multiple centres, ensuring data harmonization. bSSFP signal modelling and phantom data demonstrated good agreement, with minimal inter-site variation in signal-to-noise confirming suitability for use in our multi-centre study of lithium response in bipolar disorder. 

Nan Li^1,2, Xing Yang^1,2, Feng Du^1,2, Kang Yan³, Bei Liu³, Yiping Du³, Chunsheng Yang^4,5, Zhi Zhang^4,5, Li Chen^4,5, Fang Chen^4,5, Xiaoliang Zhang⁶, Xin Liu^1,2, Hairong Zheng^1,2, and Ye Li^1,2
1Lauterbur Imaging Research Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China;, shenzhen, China, ²Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province, Shenzhen, China, Shenzhen, China, ³Institute for Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China., Shanghai, China, ⁴State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, the Chinese Academy of Sciences, Wuhan 430071, China;, Wuhan, China, ⁵University of Chinese Academy of Science, Beijing 100049, China, Wuhan, China, ⁶Department of Biomedical Engineering, State University of New York at Buffalo, NY, United States, Buffalo, NY, United States

       Affected by the inherent physical properties, it was challenging to obtain the imaging of heteronuclear at 3T, which usually have weak MR signals. Hence, high performance was required of the RF system to excite and receive MR signals. In this study, a range of imaging tests were performed on the phantom by using the developed specific quadruple-nuclear RF coil system. The results demonstrated the feasibility of synchronized ¹H/¹⁹F/ ²³Na/³¹P MR imaging at 3T. Furthermore, the imaging approach combined the quadruple-nuclear RF coil and triple tuned local ¹⁹F/²³Na/³¹P receive coil was also indicated the improved SNR of corresponding nucleus.

Daria V Fomina^1,2, Elnur G Sadykhov³, Petra Hanson^4,5, Christopher J Philp¹, Harpal S Randeva^4,5, J Paul O'Hare^4,5, Olga S Pavlova^3,6, Nikolay V Anisimov⁶, Alexander M Makurenkov³, Yury A Pirogov³, Thomas M Barber^4,5, Thomas Meersmann¹, and Galina E Pavlovskaya^1,2
1SPMIC, School of Medicine, University of Nottingham, Nottingham, United Kingdom, ²NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom, ³Faculty of Physics, Lomonosov Moscow State University, Moscow, Russian Federation, ⁴Warwick Medical School, University of Warwick, Coventry, United Kingdom, ⁵Warwickshire Institute for the Study of Diabetes Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire, Coventry, United Kingdom, ⁶Faculty of Fundamental Medicine, Lomonosov Moscow State University, Moscow, Russian Federation

Skin plays an important role in sodium regulation in the human body. As sodium interaction with macromolecules in biological tissue results in a bi-exponential T₂ relaxation, a sensitive characterization of the molecular environment of the sodium ions can be made. This allows us to investigate sodium relaxation times, T_2short and T_2long, in human skin samples from patients with and without Type 2 Diabetes Mellitus (T2DM) using high-resolution ²³Na MRS at high field 9.4T. We find that there is a significant elongation of T_2long in T2DM patients. This might be indicative of disease specific skin structure changes.

Anne Adlung¹, Nadia Karina Paschke¹, Alena-Kathrin Golla^1,2, Dominik Bauer^1,2, Sherif Mohamed³, Melina Samartzi⁴, Marc Fatar⁴, Eva Neumaier Probst³, Frank Gerrit Zöllner^1,2, and Lothar Rudi Schad^1
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ²Mannheim Institute for Intelligent System in Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ³Department of Neuroradiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ⁴Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany

This study investigates factors of k-space undersampling for which CNN postprocessing is able to improve ²³Na MRI data. Data from 53 patients with ischemic stroke was included and image reconstruction was performed with full k-space data (FI) and with k-space data that was reduced (RI) by different factors (S = 2, 4, 5 and 10). Postprocessing with a convolutional neural network was applied to the highly undersampled ²³Na MRI data. The CNN was able to significantly improve SNR and SSIM for all S with both loss functions. CNN postprocessing could enable significant reduction of ²³Na MRI data acquisition time.

TERESA GERHALTER¹, Anna M. Chen¹, Seena Dehkharghani¹, Rosermary Peralta¹, Fatemeh Adlparvar¹, James S. Babb¹, Tamara Bushnik², Jonathan M. Silver³, Brian S. Im², Stephen P. Wall⁴, Ryan Brown¹, Guillaume Madelin¹, and Ivan Kirov^1
1Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, NEW YORK, NY, United States, ²Department of Rehabilitation Medicine, New York University Grossman School of Medicine, NEW YORK, NY, United States, ³Department of Psychiatry, New York University Grossman School of Medicine, NEW YORK, NY, United States, ⁴Ronald O. Perelman Department of Emergency Medicine, New York University Grossman School of Medicine, NEW YORK, NY, United States

In this quantitative sodium MRI study, 27 mild traumatic brain injury (mTBI) and 19 controls were scanned at 3 T. Linear regression analysis was used to measure total sodium concentrations (TSC) in global grey and white matter. We found statistically significant lower global grey and white matter TSC in mTBI patients compared to controls. This suggests that sodium imbalances in TBI, well-recognized from basic research, can be detectable non-invasively, are widespread over the entire brain, and are present even when the injury is clinically mild.

Anne Adlung¹, Sherif Mohamed², Nadia Karina Paschke¹, Mara Berger¹, Melina Samartzi³, Marc Fatar³, Achim Gass⁴, Eva Neumaier Probst², and Lothar Rudi Schad^1
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ²Department of Neuroradiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ³Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ⁴Heidelberg University, Mannheim, Germany

²³Na MRI is an indicator for cell viability and quantification provides the tissue sodium concentration (TSC). Aim of this study is to evaluate the reliability of cerebrospinal fluid (CSF) and vitreous humor (VH) as internal references for TSC quantification. Data of 49 patients with ischemic stroke was included for TSC quantification which was performed based on signal intensity within external references, CSF and VH. TSC of healthy tissue was significantly lower compared to pathological tissue. Results showed a high similarity between the three quantification methods. Internal references would simplify ²³Na MRI measurements and thus its clinical establishment.

Dennis Kleimaier¹, Simon Reichert¹, Victor Schepkin², and Lothar R. Schad^1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, ²National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, United States

This study demonstrates that amino acids and the protein α-LA do not yield a sodium TQ signal. Despite a significant reduction in sodium relaxation times, a sodium TQ signal was not observed for the amino acids glutamic acid, arginine, and lysine, as well as for the small sized protein α-LA up to their highest concentration dissolvable in water. In contrast, a BSA concentration of 3% w/v was already sufficient for the creation of a sodium TQ signal. Consequently, in vivo small molecules can only contribute to a reduction in the MR relaxation times without a detectable sodium TQ signal.

Hao Song¹, Burak Akin¹, Johannes Fischer¹, Ali Caglar Özen^1,2, Stefan Schumann³, and Michael Bock^1,2
1Dept. of Radiology, Medical Physics, Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany, ²German Consortium for Translational Cancer Research (DKTK), Partner Site Freiburg, Freiburg, Germany, ³Dept. of Anesthesiology and Critical Care, Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany

Dynamic ¹⁷O-MRI with inhalation of isotope-enriched ¹⁷O₂ is capable of directly quantifying the cerebral metabolic rate of oxygen consumption (CMRO₂). In this work, we investigated oxygen metabolism in brain subcortical structures including thalamus, dorsal striatum, caudate nucleus and insula cortex. The determined CMRO₂ values in these areas were compared with literature values obtained by PET studies. Our results show the feasibility of measuring local CMRO₂ in brain subcortical structures using ¹⁷O-MRI at 3T.

Marina Y Khodanovich¹, Andrey E Akulov², Tatyana V Anan’ina¹, Elena P Krutenkova¹, and Anna V Naumova^3
1Research Institute of Biology and Biophysics, Tomsk State University, Tomsk, Russian Federation, ²Institute of Cytology and Genetics, Novosibirsk, Russian Federation, ³Radiology, University of Washington, Seattle, WA, United States

The present work demonstrates feasibility of longitudinal visualization of neurogenesis in vivo with MRI gene reporter ferritin and fluorescent reporter eGFP expressed under the doublecortin promoter. Main source of the signal hypointensity in the brain neurogenic zones were mature and young neurons. Main source of the signal hypointensity in the ischemic lesion area were macrophages.

Josephine L Tan^1,2, Daniel Djayakarsana^1,2, Hanzhi Wang^1,2, Rachel W Chan², Colleen Bailey^1,2, and Angus Z Lau^1,2
1Medical Biophysics, University of Toronto, Toronto, ON, Canada, ²Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada

Elevated lactate production, a key characteristic of the aberrant tumour metabolism, can be detected non-invasively by deuterium (²H) magnetic resonance spectroscopy (MRS). To determine if ²H-labeled lactate measured by ²H MRS can serve as an early marker of tumour response, we investigate the association of treatment-induced signal changes in ²H-lactate in vitro with apoptotic cell death. We show that significantly lower ²H-lactate in 48-hour cisplatin treated cells (1.6 ± 0.4 mM) compared to those untreated (3.2 ± 0.4 mM) and 24-hour treated cells (4.0 ± 0.6 mM) is associated with with an increase in apoptotic area fraction.

Asaduddin Muhammad¹, Wonsik Jung², Sangyong Jon², and Sung-Hong Park^1
1Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea, Republic of, ²Biological science, Korea Advanced Institute of Science and Technology, Daejeon, Korea, Republic of

Non-Alcoholic steatohepatitis (NASH) is a liver condition that has been linked heavily as a precursor to irreversible cirrhosis condition. The symptoms are often silent or non-specific to NASH, causing diagnosis to be difficult. Emerging works in theragnostics have open a chance to diagnose NASH using MRI systems. In this study, we present a three-compartment model that is sensitive to NASH progression. A kinetic parameter derived from the model linearly increased as NASH disease progressed. This study revealed possibility of using contrast agent and compartment modeling to quantitatively analyze the NASH progression.

Yuning Gu¹, Huiyun Gao², Kihwan Kim¹, Yunmei Wang², and Xin Yu^1,3
1Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ²Medicine, Case Western Reserve University, Cleveland, OH, United States, ³Radiology, Case Western Reserve University, Cleveland, OH, United States

An oxygen-17 (¹⁷O) MRI method combining 3D golden-means-based radial sampling with model-based parameter mapping was developed for non-invasive measurement of cerebral metabolic rate of oxygen (CMRO₂) after inhalation of ¹⁷O-oxygen (¹⁷O₂).  The method enabled quantification of CMRO₂ in post-stroke mouse brain with a nominal isotropic spatial resolution of 1.6 mm.  CMRO₂ was 1.5 to 2.5 μmol/g/min in the normal tissue, and was ~1 μmol/g/min in the infarct region.

Yoshie Omiya¹, Utaroh Motosugi², Hiroyuki Morisaka¹, and Hiroshi Onishi^1
1University of Yamanashi, Yamanashi, Japan, ²Kofu-Kyoritsu Hospital, Yamanashi, Japan

Stereotactic body radiotherapy (SBRT) is a treatment option for patients with hepatocellular carcinoma (HCC). It has been difficult to know radiation induced liver damage by SBRT using conventional imaging modalities. In this study, we evaluated the liver parenchymal changes after SBRT using two quantitative MR imaging; stiffness measurement with MR Elastography(MRE) and the apparent diffusion coefficient (ADC) values with DWI.Liver stiffness and ADC values were significantly elevated in both the liver parenchymal areas receiving large radiation dose (>30Gy) and small radiation dose(<15Gy). Liver stiffness and ADC values might be able to catch the substantial liver parenchymal changes after SBRT.

Loreen Ruhm^1,2, Nikolai Avdievitch¹, Theresia Ziegs^1,2, Armin M. Nagel^3,4, Henk M. De Feyter⁵, Robin A. de Graaf⁵, and Anke Henning^1,6
1High-Field MR Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany, ²IMPRS for Cognitive and Systems Neuroscience, Eberhard-Karls University, Tuebingen, Germany, ³Institute of Radiology, University Hospital Erlangen, Erlangen, Germany, ⁴Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ⁵Radiology and Biomedical Imaging, Yale University, New Haven, CT, United States, ⁶Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, United States

DMI (Deuterium Metabolic Imaging) is a technique that enables the investigation of metabolic turnover rates along predefined pathways non-invasively. In this work, we present first DMI data from the human brain at B₀ = 9.4T and an investigation of the dynamic glucose uptake in different areas of the human head for healthy volunteers and after the oral administration of [6,6’-²H]-glucose.  We present a dedicated phased array coil design and ²H MRSI data with high spatial resolution for water, glucose, Glx and lipid/lactate. Finally, we compare the uptake curves for different regions in the human head.

Javad Parsa¹ and Andrew Webb^1
1Leiden University Medical Center, Leiden, Netherlands

Phantom 19F images have been obtained from perflurooctylbromide (PFOB) at very low magnetic field (2.15 MHz). The small spectral dispersion (in Hz) means that all fluorine nuclei contribute to the signal without chemical shift artifacts or the need for specialized sequences. Long turbo spin echo trains with short interpulse intervals and full 180o refocussing pulses suppress scalar coupling, leading to long apparent T2 values and highly efficient data collection. Overall, the detection efficiency of PFOB is actually higher than that of tissue protons at very low field.