Magnetic resonance imaging (MRI) has become the imaging modality of choice
for most questions in neuroradiology. However, MR spectroscopy (MRS) has been used in
both in vitro and in vivo long before the wide distribution of MRI in a clinical setting. The
techniques are similar as a RF pulse with Larmor frequency is used to excite the hydrogen
nuclei, in MRS, however, there is no read-out gradient. Instead of acquiring the spatial
information of a probe, the frequency information is used to identify different chemical
compounds. The different peak intensities change according to the molecular composition
of the sample, which may be different depending on the underlying disease. This provides
different information about basic metabolic processes, such as energy metabolism,
neuronal integrity, cell proliferation and degradation and necrotic changes in the tissue. The
scope of this chapter is to give an overview on the physical background of the technique
and typical clinical applications of MRS, such as brain development, noxa during
pregnancy, developmental delay, mitochondrial disorders, leukodystrophias,
neurodegenerative diseases, infections, stroke and brain tumors.
Keywords: Brain tumors, leukodystrophia, magnetic resonance spectroscopy,
mitochondrial disorders, neurodegenerative disorders, neuroradiology.
