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PubMed · 1569867

Wavelet-encoded MR imaging.

J B Weaver·Y Xu·D M Healy·J R Driscoll
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Abstract

Wavelet encoding is presented and compared to phase encoding. In wavelet encoding a distribution of spins is excited by a slice selective RF pulse; for each repetition time the distribution excited has the profile of a wavelet at different scale and translation. The spin density can be reconstructed with an inverse wavelet transform. Wavelet encoding has three advantages over phase encoding: (1) there is no Gibb's ringing from partial volume effects, (2) the effective repetition time can be 36 times the repetition time for a 256 x 256 image, and (3) motion artifacts are local and dramatically reduced. Using wavelet encoding, a 256 x 256 T2-weighted projection image can be acquired in 33 s.

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ArtifactsHumansMagnetic Resonance ImagingTime FactorsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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J B Weaver, Y Xu, D M Healy, J R Driscoll. 1992. Wavelet-encoded MR imaging.. https://doi.org/10.1002/mrm.1910240209

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PubMed2001

Cytologic artifacts and pitfalls of thyroid fine-needle aspiration using ThinPrep: a comparative retrospective review.

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