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. 2021 Feb;34(2):e4445.
doi: 10.1002/nbm.4445. Epub 2020 Nov 17.

Ultra-high-field MRI using composite RF (STEP) pulses

Roger Ordidge  1 , Jon Cleary  1 , Rebecca Glarin  1 , Yasmin Blunck  1 , Shawna Farquharson  2 , Bradford Moffat  1
Affiliations

Ultra-high-field MRI using composite RF (STEP) pulses

Roger Ordidge et al. NMR Biomed. 2021 Feb.

Abstract

Ultra-high field MRI offers many opportunities to expand the applications of MRI. In order for this to be realized, the technical problems associated with MRI at field strengths of 7 T and greater need to be solved or mitigated. This paper explores the use of new variations of composite RF pulses, named serial transmit excitation pulses (STEP), in contrast to parallel pulse techniques, in order to remove and/or mitigate the effects of non-uniform B1 excitation fields associated with the subject (eg the human brain). Several techniques based on STEP sequences are introduced and their application to human brain imaging is presented and evaluated.

Keywords: B0 inhomogeneity correction; B1 inhomogeneity correction; RF pulse design; brain imaging; other applications; ultra-high field.

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References

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