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Fast monitoring of T1, T2, and relative proton density (M0) changes in skeletal muscles using an IR-TrueFISP sequence

✍ Scribed by Paulo Loureiro de Sousa; Alexandre Vignaud; Servanne Fleury; Pierre G. Carlier


Book ID
102904904
Publisher
John Wiley and Sons
Year
2011
Tongue
English
Weight
880 KB
Volume
33
Category
Article
ISSN
1053-1807

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✦ Synopsis


Abstract

Purpose:

To investigate the feasibility of fast and simultaneous assessment of T~1~, T~2~, and M~0~ (relative proton density) changes in skeletal muscle studies using an inversion recovery true fast imaging with steady‐state precession (TrueFISP) sequence.

Materials and Methods:

NMR signal dynamics in calf muscles were analyzed under four different conditions: intravenous injection of a low‐molecular weight Gd contrast agent (CA), postarterial occlusion reactive hyperemia, local cooling, and an exercise bout. Experiments were conducted on a clinical 3T whole‐body scanner.

Results:

At rest, average muscle T~1~ and T~2~ values obtained from the IR‐TrueFISP experiments were 1.34 ± 0.13 seconds and 45 ± 5 msec, respectively (median ± standard deviation). 1) Noticeable T~1~ decreases (ΔT~1~ max ≈−30%) were measured in the calf muscles after CA injection, while no significant changes were observed for T~2~ and M~0~. 2) T~2~ increased rapidly during reactive hyperemia and reached a peak value (+6%) at about 1 minute postischemia. During ischemia, a significant decrease was observed only in the soleus muscle. No significant paradigm‐related changes in M~0~ and T~1~ were noted in all muscle groups, except in the m. soleus (ΔT~1~ ≈+1% during reactive hyperemia). 3) Opposite variations in muscle T~1~ (ΔT~1~ max ≈−30%) and M~0~ (ΔM~0~ max ≈+25%) associated with local cooling were detected. 4) Concomitant changes in T~1~ (ΔT~1~ max ≈+15%), T~2~ (ΔT~2~ max ≈+35%), and M~0~ (ΔM~0~ max ≈+16%) were observed in the activated muscles following the exercise bout.

Conclusion:

IR‐TrueFISP was sufficiently fast and sensitive to detect small and transient T~1~, T~2~, and M~0~ changes in the calf muscles under different experimental conditions. The sequence offers a time‐resolution adequate to track rapid physiological adaptations in skeletal muscle. J. Magn. Reson. Imaging 2011;33:921–930. © 2011 Wiley‐Liss, Inc.