Experimental strategies for in vivo 13 C NMR spectroscopy.

In vivo carbon-13 (13 C) MRS opens unique insights into the metabolism of intact organisms, and has led to major advancements in the understanding of cellular metabolism under normal and pathological conditions in various organs such as skeletal muscles, the heart, the liver and the brain. However, the technique comes at the expense of significant experimental difficulties. In this review we focus on the experimental aspects of non-hyperpolarized 13 C MRS in vivo. Some of the enrichment strategies which have been proposed so far are described; the various MRS acquisition paradigms to measure 13 C labeling are then presented. Finally, practical aspects of 13 C spectral quantification are discussed.