Mukherji SK, consulting ed. Brandao LA, guest ed. MR Spectroscopy of the Brain. Elsevier; August 2013. Neuroimaging Clinics of North America; vol. 23; no. 3; pgs. 359–562; $489.
MR Spectroscopy of the Brain is a welcome addition to the Neuroimaging Clinics of North America series this August 2013. The editor, Lara Brandao, and the 20 contributors take the reader through the important aspects of MRS, from its basic underpinnings to the clinical applications of this technique. Ten chapters—two on the overview of MRS and techniques involved, eight on how MRS can be used to clarify, illuminate, or solve routine imaging issues—comprise the contents of this 200-page issue.
There is information here for neuroradiologists at every level, from the basics of how a spectra is obtained to applications in evaluating some of the more confusing diseases of the brain. While most readers of the AJNR are familiar with and may frequently use MRS, whether multivoxel or single voxel, for commonly encountered abnormalities such as brain tumors or infections, less is appreciated about its use in a wide variety of disorders such as metabolic diseases, epilepsy, MS, and dementias, as well as how spectra change from infancy onward. Herein lies the value of this issue of the NICNA.
Take the chapter entitled “MRS in Metabolic Disorders” as one example, written by Drs. Rossi and Biancheru. In 23 pages a myriad of metabolic diseases are analyzed with MRS, and, as we know, many of these have nearly similar appearances on routine MRI, thereby defying a specific diagnosis. We see here how a spectral analysis may assist in clarifying the situation.
Metabolites one usually does not consider (because, most commonly, one looks at TE sequences in adults) include those manifest in metabolic disorders such as glutamate complexes, increased lactate (MELAS), glycine increases (NKH), creatine deficiency, branched-chain amino acid increases (MSUD), and prominent myoinositol among others. In addition, the chapter delves into the physiological and biochemical abnormalities that result in these disorders, looking at why NAA is increased in Canavan’s Disease and how that results in the creation of abnormal white matter, for example. Other metabolic diseases are similarly summarized as concerns their biochemical basis. Besides the analysis of MRS alterations, this chapter serves as a nice review of routine MRI in all the important infantile and childhood CNS metabolic disorders.
Most readers’ attention will turn to the use of spectroscopy in tumors and infections. The succinct writing and well-illustrated examples clarify details about the less commonly considered moieties such as amino acids, acetate, succinate, and trehalose. The significance of each of these in terms of the underlying causative organism is explained so that one appreciates why, for example, amino acids are high in abscesses, why anaerobic vs. aerobic abscesses may give different spectra (succinate vs. acetate), the variability of tuberculomas (caseating/noncaseating) and tuberculous abscesses, and the spectral appearance (along with MRI) in fungal abscesses.
Other chapters in this book cover adult and pediatric brain tumors, dementias (surprisingly no spectra seen), epilepsy, multiple sclerosis, and poxia/ischemia, to round out this important addition to the NICNA series.
