Examining Saturation Corrections for In-Vivo Liver 1H-MRS Glycogen Measurements in a Clinical 3T Scanner

Ronald Ouwerkerk¹

Single volume ¹H-MRS can be used to measure human liver glycogen in vivo, but various factors could lead to quantitation errors. T₁ and T₂ relaxation effects were examined on glycogen phantoms with ionic strength, pH and temperature mimicking the intracellular environment of the liver using the same PRESS sequence and parameters used for in-vivo measurements of glycogen in humans. Signal variations as a function of echo time (TE) and echo spacing with a fixed TE showed effects of homonuclear coupling. Thus, assuming an exponential model to correct glycogen signals for relaxation could lead to an underestimation of the glycogen concentrations.