Effects of muscle fiber orientation to main magnetic field on muscle metabolite profiles for magnetic resonance spectroscopy acquisition

Table 1 The median (25^th-75^th percentile) values of IMCL (CH₃), EMCL (CH₃), IMCL (CH₂), and EMCL (CH₂) ratios to creatine with the muscle positioned at 0°, 30°, 60°, and 90° to the main magnetic field

Angle	Metabolite
	IMCL (CH3), 0.9 ppm	P value	EMCL (CH3), 1.1 ppm	P value	IMCL (CH2), 1.3 ppm	P value	EMCL (CH2), 1.5 ppm	P value
0°	1.44 (1.36-1.47)	-	4.25 (4.22-5.35)	-	2.96 (2.53-2.99)	-	3.08 (2.09-3.46)	-
30°	0.80 (0.77-0.81)	0.017a	1.23 (1.16-1.33)	0.017a	0.55 (0.46-0.60)	0.017a	0.28 (0.04-0.44)	0.017a
60°	1.15 (0.86-1.19)	0.018a	2.03 (1.69-2.08)	0.018a	0.77 (0.68-0.91)	0.018a	0.04 (0.04-0.11)	0.042a
90°	0.64 (0.62-0.64)	0.018a	1.29 (1.27-1.32)	0.018a	0.30 (0.72-0.31)	0.018a	-	-

The P-value shows the comparison between the metabolite ratios to creatine at 0° vs the different angles, as determined by Wilcoxon signed-rank test (n = 7). Data are expressed as medians (25^th-75^th percentiles).

^aP-value < 0.05, significantly different.

EMCL: Extramyocellular lipids; IMCL: Intramyocellular lipids.