Proton magnetic resonance spectroscopy in skeletal muscle: Experts' consensus recommendations

Abstract

H-MR spectroscopy of skeletal muscle provides insight into metabolism that is not available noninvasively by other methods. The recommendations given in this article are intended to guide those who have basic experience in general MRS to the special application of 1 H-MRS in skeletal muscle. The highly organized structure of skeletal muscle leads to effects that change spectral features far beyond simple peak heights, depending on the type and orientation of the muscle. Specific recommendations are given for the acquisition of three particular metabolites (intramyocellular lipids, carnosine and acetylcarnitine) and for preconditioning of experiments and instructions to study volunteers.

Terminology and concepts for the characterization of in vivo MR spectroscopy methods and MR spectra: Background and experts' consensus recommendations

“…Residual dipolar coupling: Partially detectable dipolar coupling in partially oriented molecules, where the physics is identical to dipolar coupling, but the size of the coupling is reduced by partial averaging reflecting the degree of orientation (eg, in liquid crystals or in vivo in 1 H MRS of skeletal muscle) 141,142 …”

“…Orientation dependence: Dependence of a parameter or spectrum on the orientation of the investigated object (eg, muscle fiber or microscopic non‐spherical object) with respect to B 0 141,142 …”

“…Susceptibility shifts: Shift of resonance frequency due to local susceptibility effects either mediated through the susceptibility difference of investigated material or neighboring structure of different magnetic susceptibility (eg, susceptibility shifts of fat or blood vessels vs. tissue). This can lead to peak splitting if a certain metabolite is present in two environments with different susceptibilities (as is the case for intra‐ and extramyocellular lipids 142,143 ).…”

Muscle‐Specific Relation of Acetylcarnitine and Intramyocellular Lipids to Chronic Hyperglycemia: A Pilot 3‐T 1H MRS Study

“…Results from our previous studies, as well as from other studies, are reported in mmol/kg ww units. However, as was suggested in a recent consensus paper by Krššák et al (19), results of acetylcarnitine concentrations are given in mmol/L tissue volume units.…”

Comparison of single-voxel 1H-cardiovascular magnetic resonance spectroscopy techniques for in vivo measurement of myocardial creatine and triglycerides at 3T

“…The Magnetic Resonance Spectroscopy Consensus Group recommended the use of sLASER at high fields (≥ 3 T) for brain [ 14 ] and musculoskeletal [ 15 ] applications to improve reproducibility of data acquisition and metabolite quantification. sLASER has the advantages to provide a considerably lower CSDE with a sharper voxel localization compared to PRESS [ 16 , 17 ].…”