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Algorithms for extracting motion information from navigator echoes

✍ Scribed by Yi Wang; Roger C. Grimm; Joel P. Felmlee; Sephen J. Riederer; Richard L. Ehman

Publisher
John Wiley and Sons
Year
1996
Tongue
English
Weight
721 KB
Volume
36
Category
Article
ISSN
0740-3194

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✦ Synopsis

Abstract

Algorithms to reliably detect motion in navigator echoes are crucial to many MRI motion suppression techniques. The accuracy of these algorithms is affected by noise and deformation of navigator echo profile caused by physiologic motion. This study compared the performance of algorithms based on correlation and least squares for extracting displacement information from motion‐monitoring navigator echoes, using computer simulation and in vivo imaging. The least squares algorithm was determined to be of higher accuracy than the correlation algorithm against errors caused by noise and profile deformation.

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