Reproducibility of single- and multi-voxel 1H MRS measurements of intramyocellular lipid in overweight and lean subjects under conditions of controlled dietary calorie and fat intake.

Publication Type	Academic Article
Authors	Shen W, Mao X, Wolper C, Heshka S, Dashnaw S, Hirsch J, Heymsfield S, Shungu D
Journal	NMR Biomed
Volume	21
Issue	5
Pagination	498-506
Date Published	06/01/2008
ISSN	0952-3480
Keywords	Lipids, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Muscle Fibers, Skeletal, Overweight
Abstract	The reproducibility of repeated single-voxel 1H MRS (SV-MRS) and spectroscopic imaging (MRSI) measurements of intramyocellular lipid (IMCL) in the tibialis anterior muscle of five lean and five overweight female Caucasians, during 7 days of controlled dietary fat and calorie intake, was assessed at 1.5 T. Duplicate measures of IMCL relative to total muscle creatine (IMCL/tCr) obtained 3 days apart by both SV-MRS and MRSI correlated well (r = 0.65 and r = 0.95, respectively, P < 0.05). The coefficients of variation for repeated measures of IMCL/tCr by SV-MRS and MRSI were 24.4% and 10.7%, respectively. IMCL/tCr measured by MRSI was higher in overweight subjects than in lean subjects (8.3 +/- 3.8 vs 4.3 +/- 2.4, P < 0.05). Although both methods achieved good reproducibility in measuring IMCL in vivo, MRSI was found to offer greater flexibility and reliability, and higher sensitivity to IMCL differences, whereas SV-MRS was advantageous with respect to shorter scan time and ease of implementation.
DOI	10.1002/nbm.1218
PubMed ID	17955571
PubMed Central ID	PMC2892914