Analysis of glycogen storage disease by in vivo 13C NMR: comparison of normal volunteers with a patient.

Broadband proton-decoupled natural abundance 13C spectra of the human calf, liver, and head were obtained from normal volunteers and a patient with glycogen type IIIA storage disease. Two concentric and coplanar surface coils of diameters 8.0 cm and 13.0 cm were used for 13C (at 16.0 MHz) and 1H (at 63.6 MHz), respectively. A WALTZ-8 sequence lead to homogeneous decoupling over a large volume. In addition to lipid resonances a variety of other metabolite resonances could be resolved. The glycogen concentration in the muscle and the liver of normal volunteers varied considerably depending on dietary preparation and physical exercise. The glycogen level in the liver and the calf of a patient with glycogen type IIIA storage disease was increased by a factor of 2-3 compared to normal, well-trained volunteers. Proton-decoupled 13C spectra of human head are reported for the first time. The spectra are dominated by lipid resonances but an additional resonance at 54.0 ppm is clearly visible. The proton-decoupled 13C head spectrum of a patient with glycogen type IIIA storage disease revealed additional resonances between 71.0 and 85.0 ppm.