ABSTRACT
PURPOSE:
To introduce a novel MR pulse sequence, termed Looping Star, for fast, robust, and yet quiet, 3D radial multi-gradient echo T2* MR imaging.METHODS:
The Looping Star pulse sequence is based on the 3D radial Rotating Ultra-Fast Imaging Sequence (RUFIS) extended by a time-multiplexed gradient-refocusing mechanism. First, multiple magnetic coherences are excited, which are subsequently gradient-refocused in form of a looping k-space trajectory. Accordingly, Looping Star captures an initial FID image followed by gradient echo images at equidistant echo times.RESULTS:
Looping Star was demonstrated in phantom and in vivo volunteer experiments for 3D, high resolution T2* weighted imaging, T2* mapping, and quantitative susceptibility mapping (QSM). The method is fast, quiet, and robust against imperfections including Eddy currents, motion, and geometric distortions. When applied to a motor task fMRI experiment a BOLD sensitivity of 5% was achieved at minimal acoustic noise (i.e. 2.7 dB(A) above ambient noise) and with images congruent to other anatomical scans.CONCLUSIONS:
Looping Star imaging provides new and exciting opportunities for fast, robust and yet quiet T2* MR imaging. Potential applications include T2*-weighted imaging, T2* mapping, QSM, and fMRI.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Encéfalo
/
Imageamento por Ressonância Magnética
Limite:
Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article