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dc.contributor.advisorJacob White.en_US
dc.contributor.authorArango, Nicolas(Nicolas S.)en_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Electrical Engineering and Computer Science.en_US
dc.date.accessioned2020-11-06T21:08:36Z
dc.date.available2020-11-06T21:08:36Z
dc.date.copyright2020en_US
dc.date.issued2020en_US
dc.identifier.urihttps://hdl.handle.net/1721.1/128411
dc.descriptionThesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, February, 2020en_US
dc.descriptionCataloged from PDF version of thesis. [d̳e̳l̳t̳a̳] in title on title page appears as upper case Greek letter.en_US
dc.descriptionIncludes bibliographical references (pages 33-35).en_US
dc.description.abstractThis work develops sequence-phase optimal (SPO) [delta]B₀ shimming methods to reduce lipid contamination and improve brain metabolite spectra in proton spectroscopic imaging. A rapidly reconfigurable 32-channel, local-multi-coil-shim-array is used to enhance lipid suppression and narrow metabolite linewidth in magnetic resonance spectroscopic imaging (MRSI) of the brain. The array is optimally reconfigured dynamically during each MRSI repetition period, first during the lipid-suppression phase, by widening the spectral gap between spatially separate lipid and metabolite regions, and then to narrow metabolite linewidth during readout, by brain-only [delta]B₀ homogenization. This sequence-phase-optimal (SPO) shimming approach is demonstrated on four volunteer subjects using a commercial 3T MRI outfitted with a 32-channel integrated RF receive and local multi-coil shim array. This proposed sequence-phase-optimal shimming significantly improves brain-metabolite MRSI in vivo, as measured by lipid suppression, brain metabolite chemical shift, and line widths. The time required to compute patient specific SPO shims negligibly impacted scan time. Sequence-phase-optimal shimming reduced lipid energy in the brain volume across four subjects by 88%, improved NAA FWHM by 23%, and dramatically reduced lipid ringing artifacts in quantified NAA and Glutamate metabolites, without increasing scan time or SAR.en_US
dc.description.statementofresponsibilityby Nicolas Arango.en_US
dc.format.extent35 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsMIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectElectrical Engineering and Computer Science.en_US
dc.titleSequence-phase optimal (SPO) [d̳e̳l̳t̳a̳]B₀ field control for lipid suppression and homogeneity for brain magnetic resonance spectroscopic imagingen_US
dc.typeThesisen_US
dc.description.degreeS.M.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Electrical Engineering and Computer Scienceen_US
dc.identifier.oclc1203061574en_US
dc.description.collectionS.M. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Scienceen_US
dspace.imported2020-11-06T21:08:34Zen_US
mit.thesis.degreeMasteren_US
mit.thesis.departmentEECSen_US


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