In vivo magnetic resonance spectroscopy: basic methodology and clinical applications

Abstract

The clinical use of in vivo magnetic resonance spectroscopy (MRS) has been limited for a long time, mainly due to its low sensitivity. However, with the advent of clinical MR systems with higher magnetic field strengths such as 3 Tesla, the development of better coils, and the design of optimized radio-frequency pulses, sensitivity has been considerably improved. Therefore, in vivo MRS has become a technique that is routinely used more and more in the clinic. In this review, the basic methodology of in vivo MRS is described—mainly focused on 1H MRS of the brain—with attention to hardware requirements, patient safety, acquisition methods, data post-processing, and quantification. Furthermore, examples of clinical applications of in vivo brain MRS in two interesting fields are described. First, together with a description of the major resonances present in brain MR spectra, several examples are presented of deviations from the normal spectral pattern associated with inborn errors of metabolism. Second, through examples of MR spectra of brain tumors, it is shown that MRS can play an important role in oncology.

Tumor imaging using hyperpolarized 13C magnetic resonance spectroscopy

“…To date, [1][2][3][4][5][6][7][8][9][10][11][12][13] C]pyruvate has been the most commonly used metabolite for DNP. Intravenous injection of [1-13 C]pyruvate can result in the appearance of [1-13 C]lactate, [1][2][3][4][5][6][7][8][9][10][11][12][13] C]alanine, and 13 CO 2 resonances, depending on the tissue probed and its metabolic state.…”

“…Intravenous injection of [1-13 C]pyruvate can result in the appearance of [1-13 C]lactate, [1][2][3][4][5][6][7][8][9][10][11][12][13] C]alanine, and 13 CO 2 resonances, depending on the tissue probed and its metabolic state. Lactate labeling results from the reaction catalyzed by the enzyme lactate dehydrogenase (LDH) and alanine labeling from a transamination reaction catalyzed by alanine transaminase.…”

“…However, one of the great strengths of magnetic resonance (MR) is spectroscopy, which allows imaging of tissue biochemistry; this was recognized in the earliest applications of MR to intact biological systems (1). Although magnetic resonance imaging (MRI) has become a routine clinical tool, the use of magnetic resonance spectroscopy (MRS) in patients has lagged far behind; this has been primarily due to a lack of sensitivity, which leads to long measurement times and poor image resolution (2)(3)(4)(5). In spite of this, 1 H-MRS measurements of cellular metabolites in a variety of tumor types have been shown to provide a sensitive means to diagnose disease and detect response to treatment (2)(3)(4).…”

Non-invasive grading of astrocytic tumours from the relative contents of myo-inositol and glycine measured by in vivo mrs

“…Candiota 1,2 , C. Majós 3,1 , M. Julià-Sapé 1,2,4 , M. Cabañas 5,1 , J.J. Acebes 6,1 when gly is its major contributor. Barba et al (20) utilised this echo time J-coupling modulation-dependent effect to estimate the relative mI and Gly content in human brain tumours in vivo.…”

“…MRI and MRS are well established methodologies for evaluating intracranial lesions (1,2). MRS is nowadays receiving increasing attention from radiologists and neurologists, and its use to help MRI in even here accuracy is not perfect (7).…”