Code: ThOD	Time Slot/Poster Number: 4:00-4:25	Session: in vivo NMR Spectroscopy
High field clinical spectroscopy using B0 and B1 shimming
Dennis Klomp; Vincent Boer; Peter Luijten
Radiology, University Medical Center Utrecht, Utrecht, the Netherlands
Abstract
MR spectroscopy in human tissue reveals a wealth of metabolic information that can be obtained in vivo, not only from a single region of interest, but spatially mapped over any organ of interest. Increasing the B0 field strength can improve both the spatial and spectral resolution, which benefits in distinguishing different metabolites at reduced partial volume effects. The increased sensitivity at higher field strengths can be used to detect signals more accurately also from nuclear spins other than hydrogen (i.e. 31P, 19F, 13C, etc.). Here we explore the use of 7T MR spectroscopy in a clinical setting using B0 and B1 shimming to obtain metabolite information from brain, breast and prostate tissue in vivo.

Code: ThOD	Time Slot/Poster Number: 4:25-4:40	Session: in vivo NMR Spectroscopy
Detection of the Metabolism of Different Substrates in the Carboxylic/Amide Region Using in vivo 13C MRS
Yun Xiang
NIMH, Bethesda, MD
Abstract
In the carboxylic/amide region, brain 13C signals can only have one one-bond 13C-13C homonuclear coupling. As such only doublets (with a 13C-13C coupling of ~50 Hz) and singlets exist in this region. The large one-bond 13C-13C J coupling and the lack of interference from other isotopomers provide a unique condition for simultaneous detection of metabolism of different substrates. Examples of co-infusion of [13C6]-D-glucose and [1-13C] acetate as well as co-infusion of [13C6]-D-glucose and [1,3-13C2] hydroxybutyrate are shown to demonstrate in vivo simultaneous detection of different metabolic pathways in the brain using 13C MRS of the carboxylic/amide region.

Code: ThOD	Time Slot/Poster Number: 4:40-5:05	Session: in vivo NMR Spectroscopy
31P MRS Studies of Depression: Implications for Treatment
Perry Renshaw
Department of Psychiatry, The Brain Institute, Uni, Salt Lake City, UT
Abstract
Phosphorus-31 (31P) MRS studies of Major Depressive Disorder (MDD) patients have demonstrated decreased brain levels of beta nucleoside triphosphate (bNTP) and increased levels of phosphocreatine (PCr) compared to healthy controls. This unusual pattern of high energy phosphates is observed more often in those who go on to respond to antidepressant treatment than in nonresponders, suggesting that baseline levels of bNTP and PCr may be predictors of treatment response. Creatine monohydrate supplementation has been shown to decrease levels of bNTP and increase levels of PCr in healthy volunteers. This supplement has also been shown to decrease depressive symptoms in female rats and, more recently, in women treated with escitalopram. This evidence supports the hypothesis that 31P magnetic resonance spectroscopy may be useful for the assessment and management of MDD patients.

Code: ThOD	Time Slot/Poster Number: 5:05-5:20	Session: in vivo NMR Spectroscopy
Lymph Node Imaging using Multi-Color MR Contrast Agents
Guanshu Liu; Yah-el Har-el; Chris Long; Matthew Moake; Piotr Walczak; Assaf Gilad; Jiangyang Zhang; Marco DeLiso; Amanda Cardona; George Sgouros; Jeff Bulte; Peter van Zijl; Michael T. Mcmahon
Johns Hopkins Univ, Baltimore, MD
Abstract
We developed a new MR-visible liposome system based on labeling with three distinct diamagnetic Chemical Exchange Saturation Transfer (DIACEST) agents, L-arginine, poly-L-lysine and glycogen. Using saturation frequency swept MRI with B0-correction, the accumulation of all three types of DIACEST liposomes in mouse popliteal lymph nodes could be visualized. As a proof of concept, we demonstrate the first in-vivo multi-contrast (multi-color) MRI using two DIACEST agents, L-arginine liposomes and poly-L-lysine liposomes, that were simultaneously injected to two footpads of the same mouse. This new system allows direct monitoring of liposomal uptake in lymph nodes without any paramagnetic or super-paramagnetic contrast material.

Code: ThOD	Time Slot/Poster Number: 5:20-5:45	Session: in vivo NMR Spectroscopy
Magnetic Field Shaping in MR Imaging and Spectroscopy
Robin de Graaf
Yale University, New Haven, CT
Abstract
Control of the spatial dynamics of magnetic fields is essential for many MR methods, ranging from linear gradients in MRI to more complex magnetic fields to achieve high magnetic field homogeneity. Here a novel approach to achieve magnetic field shaping is introduced in which highly complex magnetic fields can be created with a limited matrix of circular, direct current (DC) coils. A sufficiently large matrix can provide near-perfect magnetic field homogeneity, but can also readily create linear gradients as required for MRI. One of the greatest strengths of DC coil matrices is that accuracy and strength of the generated magnetic fields can be optimized for each particular object or region-of-interest, leading to high efficiencies especially for more complex magnetic fields.

Code: ThOD	Time Slot/Poster Number: 5:45-6:00	Session: in vivo NMR Spectroscopy
Novel Experimental Approach for Simultaneous Determination of Glucose and Oxygen Consumption in Live Animals
A. Ye; B. Erokwu; C. Flask; J. Duerk; G. Mateescu
Case Western Reserve University, Cleveland, OH
Abstract
Following intravenous or intraperitoneal administration of deuteriated glucose in mice, in vivo Dynamic Deuterium MR spectroscopy (DDMRS) affords simultaneous assessment of glucose and oxygen consumption by monitoring the glucose 6,6-d2 signal decay and the increasing intensity of the peak of nascent mitochondrial water (HDO). The rates of these processes can be directly determined from a single DDMRS graph. The position of the crossing point of the two curves may constitute a new marker of the bioavailability of glucose and of the mitochondrial function. The experiments were performed with a home built small animal Deuterium transmit-receive coil in a Bruker Biospec 9.4 Tesla MRI scanner.