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Reduction of signal fluctuation in functional MRI using navigator echoes

✍ Scribed by Xiaoping Hu; Seong-Gi Kim

Publisher
John Wiley and Sons
Year
1994
Tongue
English
Weight
963 KB
Volume
31
Category
Article
ISSN
0740-3194

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✦ Synopsis

Abstract

Functional magnetic resonance imaging is sensitive to signal fluctuations due to physiological motion and system instability. In this paper, motion‐related signal fluctuations are studied, and a method that uses navigator echoes to monitor and compensate for signal fluctuations in a gradient‐echo sequence is described. The technique acquires a “navigator” signal before the application of the phase‐encoding and readout gradients and corrects the phase of the subsequently acquired imaging data. This technique was implemented on a 4 Tesla whole body system and validated on normal volunteers. With this technique, temporal fluctuations in image intensity were substantially reduced and improved functional activation maps were obtained.

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