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A strategy for sampling on a sphere applied to 3D selective RF pulse design.

S T Wong·M S Roos
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Abstract

Conventional constant angular velocity sampling of the surface of a sphere results in a higher sampling density near the two poles relative to the equatorial region. More samples, and hence longer sampling time, are required to achieve a given sampling density in the equatorial region when compared with uniform sampling. This paper presents a simple expression for a continuous sample path through a nearly uniform distribution of points on the surface of a sphere. Sampling of concentric spherical shells in k-space with the new strategy is used to design 3D selective inversion and spin-echo pulses. These new 3D selective pulses have been implemented and verified experimentally.

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HumansImage Processing, Computer-AssistedMagnetic Resonance ImagingMagnetic Resonance SpectroscopyNoiseJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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S T Wong, M S Roos. 1994. A strategy for sampling on a sphere applied to 3D selective RF pulse design.. https://doi.org/10.1002/mrm.1910320614

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