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Abstract #4397

Improving in vivo 1H-MRS with Robust Automated Shim Techniques: A Comparison Study of FASTESTMAP and GRESHIM

Xiaodong Zhong1, Yevgeniya M. Lyubich2, Timothy DeVito3, Saurabh Shah4, Jack Knight-Scott2

1MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States; 2Department of Radiology, Children's Healthcare of Atlanta, Atlanta, GA, United States; 3Siemens Canada Limited, London, Ontario, Canada; 4MR R&D Collaborations, Siemens Healthcare, Chicago, IL, United States

In this study, we examined the robustness of three automated shimming techniques for single-voxel spectroscopy at 3T: FASTESTMAP, GRESHIM, and a standard vendor-offered product. Qualitative and quantitative results across six brain regions over five participants anterior cingulate, posterior cingulate, centrum semiovale, hippocampus, Brocas area, and thalamus show that FASTESTMAP and GRESHIM provide the robustness and reliability necessary for implementation in the clinical environment, while the vendor-supplied shimming technique did not. Of the six regions examined, only the iron-rich thalamus could not be shimmed appropriately. Our results suggest that FASTESTMAP and GRESHIM should greatly improve the reliability of clinical spectroscopy.

Keywords

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