Magnetic Resonance Spectroscopy Technology Research Articles

Metabolic parameters of epilepsy: adjuncts to established antiepileptic drug therapy.

Hughlings Jackson at the turn of the century defined epilepsy as a disorder originating in a "morbid nutrition" of the neuron. With the advances in modern neurochemistry, it is becoming increasingly clear that a chronic seizure predisposition or a lowering of the brain's discharge threshold can be demarcated by a number of biochemical markers. They include a tendency for an increased release of glutamate with or without GABAergic impairment, (intra)neural tissue alterations in water redistribution/osmolarity or other distortions of the cytoarchitecture, and an elevation of ionic calcium inside the cell. These changes are dominantly shared parameters of the seizure prone brain. Magnetic resonance spectroscopy (MRS) shows that cerebral levels of glutamate + glutamine (Glx) are increased interictally in epileptogenic regions in human partial epilepsy; other findings using this technique suggest damage to (cellular/mitochondrial) membranes, denoted by N-acetyl-aspartic acid (NAA) changes and a decreased energy capability. The merging of previous in vitro and ex vivo findings in neurophysiology and neurochemistry with magnetic resonance spectroscopy technology provides a powerful new methodology to interpret and to obtain clinical insight into the metabolic alterations that underlie an epileptogenic process. In this review some of these basic neurochemical and electrophysiological mechanisms are discussed. In addition, certain adjuncts to established antiepileptic drug therapy are suggested in the hope that over the long term they may help in correcting the primary metabolic deficits.

Mood disorders: treatment-induced changes in brain neurochemistry and structure.

Continuing advances in neuroimaging technology as well as postmortem examinations have enabled researchers to begin to accumulate substantial evidence suggesting that chronic mood disorders may be associated with actual structural and neurochemical changes within the brain. There is emerging evidence to suggest that various treatment modalities may also induce measurable changes within the brain detectable with specialized neuroimaging techniques, which may be responsible for their clinical therapeutic effects. One such specialized neuroimaging technique, magnetic resonance spectroscopy (MRS), is briefly reviewed. Included is an overview of basic MRS technology and a review of its application in the study of chronic mood disorders to date. We review our recent studies investigating neurochemical changes induced by the mood stabilizer, lithium, in the treatment of bipolar disorder (BPD). Finally, in view of accumulating evidence suggesting a neuronal atrophy and cell death hypothesis for depression, we discuss the potential use of MRS to evaluate pharmacologic interventions for important potential neurotrophic and neuroprotective effects on the adult human brain.

Proton magnetic resonance spectroscopic imaging as a cancer biomarker for pediatric brain tumors (Review)

Magnetic resonance (MR) techniques offer a non-invasive, non-irradiating yet sensitive approach to diagnose and monitor cancer, which encompasses diverse processes affecting various aspects of pathophysiology. Techniques such as MR spectroscopy (MRS) have been developed and applied to monitor the metabolic aspects of cancer. Given that cancer is such a variable disease, biomarkers identified using MRS represent a promising advance and may suggest appropriate therapy, especially when diagnostic biopsies are not feasible. This article will focus on proton MRS, which appears to be the most promising MR method and is complementary to existing diagnostic methods that may be used to characterize and monitor cancer processes. We further focus on applying the MRS technology to pediatric brain tumors, the leading cause of pediatric cancer mortality.

Magnetic resonance spectroscopy in psychiatry: potential, pitfalls, and promise [published erratum appears in Am J Psychiatry 1992 Mar;149(3):431

Magnetic resonance spectroscopy (MRS) is a novel noninvasive approach to measuring important metabolites in living tissue. Its application to psychiatry is just beginning. In vivo MRS with 31P provides important information on brain phospholipid metabolism and energy production. In vivo 13C and 1H MRS can reveal information about carbohydrate, protein, and amino acid metabolism. In vivo 7Li and 19F MRS can be used to study the pharmacology of lithium and fluorinated psychopharmacological agents. MRS with 23Na can yield information about electrolyte balance. The limitations of in vivo MRS include poor sensitivity, poor resolution, and the fact that only highly mobile atomic nuclei can be detected. Future clinical application of MRS will benefit from improvements in the technology of localization, use of spectroscopy contrast agents, stronger magnets, and the merging of MRS and imaging technology.

Magnetic Resonance Spectroscopy May Hold Promise in Studying Metabolites, Tissues

ALMOST 15 years ago, in a basement at Chicago's University of Illinois Medical Center, Michael Barany, MD, PhD, measured phosphorus metabolites in an intact frog muscle using magnetic resonance spectroscopy (MRS). Prior to that, chemists used spectroscopy solely to analyze the contents of test tubes. Only a British group preceded Barany in proving that it would work in tissue as well. Today, he does spectroscopy clinically, one day a week, at the Greenberg Radiology Institute in Highland Park, Ill, north of Chicago. Barany says that he can distinguish malignant from benign tumors in the living brain. The tool he uses is a standard magnetic resonance imaging (MRI) machine. While MRI capabilities have forged ahead, human MRS has been awaiting improvements in magnet and computer technology. Barany is one of a number of researchers who, since the early 1980s, have been developing MRS technology and techniques so that it can be