Session TOB. There are 5 abstracts in this session.

Session: Quantitative in vivo MRS/MRI, time: 10:45-11:10
Phase Rotation STEAM Spectroscopy: In Vivo Application to Schizophrenia
S. Andrea Wijtenburg
University of Maryland School of Medicine, Baltimore, MD
Phase rotation STEAM (PR-STEAM) uses a specialized type of RF phase cycling and standard RF pulses to achieve very short echo times. Since it does not require specialized hardware or software, it can easily be used on a clinical MR system. PR-STEAM has been shown to reliably detect glutamate, glutamine, and glutathione in healthy adults and in adults with schizophrenia. In schizophrenia, the technique has been used primarily to study glutamate changes with aging as well as whether glutamatergic metabolites are related to cerebral blood flow, visual plasticity response, cognition, and clinical symptoms.

Session: Quantitative in vivo MRS/MRI, time: 11:10-11:35
Quantitative Hyperpolarized 13C NMR Studies of Cancer Models
Renuka Sriram; Jinny Sun; Jeremy Bancroft Brown; Hsin-Yu Chen; David Korenchan; Peder Larson; Robert Bok; Mark VanCriekinge; Daniel Vigneron; John Kurhanewicz
University of California, San Francisco, San Francisco, CA
Increasing evidence points to cancer being a disease strongly linked to abnormal metabolism and changes in the tumor microenvironment. This lecture will focus on quantitative NMR metabolic studies and pre-clinical models necessary to test the utility of new HP 13C probes of metabolism and for understanding the mechanistic underpinnings for the observed metabolic changes. Specifically, approaches using 1- and 2-D high-resolution magic angle (HR-MAS) spectroscopy of snap frozen tissues, 1-D and 2-D (1H-1H TOCSY and 1H-13C HSQC) 13C substrate-labeling studies of living tissues, and MR compatible 3D cell and tissue culture perfusion system (bioreactor) and murine model studies will be described. HP 13C MR probe applications will be demonstrated in the setting of prostate cancer progression and response to therapy.

Session: Quantitative in vivo MRS/MRI, time: 11:35-12:00
MR imaging and spectroscopy of lipid metabolism
Chris Boesch
University of Bern, AMSM, Bern, Switzerland

Lipid metabolism of the human body has contradictory facets, reaching from pandemic diseases to the basic necessity for well-being. In recent years, MR imaging and spectroscopy became increasingly important tools in clinical and preclinical studies of lipid metabolism. In contrast to acute or life-threatening diseases, derailed lipid metabolism is often hidden or apparently harmless (yet with dramatic cardiovascular consequences). While radiation or invasive methods are accepted for dramatic situations, clinical studies of lipid metabolism, in particular with healthy volunteers, benefit increasingly from the non-invasive and safe nature of MR examination. Not less important, MR imaging and MR spectroscopy can yield a wealth of highly relevant information.


Session: Quantitative in vivo MRS/MRI, time: 12:00-12:15
Language-dependent shift in neurochemical asymmetry observed by in vivo proton MRS during vocal meditation
Rama Jayasundar
Department of NMR, AIIMS, New Delhi, New Delhi, India
This study using in-vivo proton MRS in normal volunteers demonstrates language-dependent changes in neurochemical asymmetry during vocal meditation (VM), which involved repetitive utterance (108 times) of specific phrases (either in English or in Sanskrit) every morning during the active study period. Both the volunteer groups [VMS (n=5; S-sanskrit) and VME (n=5; E-English translation of the phrases)] were evaluated for VMS and VME, with a time gap of nine months. Each routine lasted for 36 weeks with three blocks (baseline, active, follow-up) of 12 weeks each. Proton spectra were acquired every week for the entire study period. Left/right asymmetry index was calculated for metabolite ratios, Naa/Cr and Naa/Cho. Reduction in asymmetry indices were observed in VMS but not the VME group.

Session: Quantitative in vivo MRS/MRI, time: 12:15-12:30
Accelerated Localized Correlated Spectroscopy with Compressed Sensing Reconstruction Using Total Variation, Group Sparsity, and Joint Hankel Low-Rank Regularization 
Andres Saucedo; Manoj K. Sarma; M. Albert Thomas
UCLA Department of Radiological Sciences, Los Angeles, CA
Compressed sensing (CS) combined with non-uniform under-sampling can significantly reduce the acquisition time of 2D magnetic resonance spectroscopy (MRS). Recently, a low-rank Hankel matrix completion method which improves upon conventional CS reconstruction has been proposed for accelerated 2D MRS. This technique relies on reconstructing the vector of all indirect t1 points separately for each F2 point. We introduce a CS-based method that implements joint Hankel low-rank (JHLR) regularization, which enforces the low-rankness of all Hankel matrices formed from the entire F2-t1 data simultaneously. We compared this method with group sparsity- (GS) and total variation- (TV) based CS reconstruction of prospectively under-sampled localized correlated spectroscopy (COSY) data in a brain phantom.