title: Potential of MR spectroscopy for assessment of glioma grading.
abstract: BACKGROUND
  Magnetic resonance spectroscopy (MRS) is an imaging diagnostic method based that allows non-invasive measurement of metabolites in tissues. There are a number of metabolites that can be identified by standard brain proton MRS but only a few of them has a clinical significance in diagnosis of gliomas including N-acetylaspartate, choline, creatine, myo-inositol, lactate, and lipids.
  
  
  METHODS
  In this review, we describe potential of MRS for grading of gliomas.
  
  
  RESULTS
  Low-grade gliomas are generally characterized by a relatively high concentration of N-acetylaspartate, low level of choline and absence of lactate and lipids. The increase in creatine concentration indicates low-grade gliomas with earlier progression and malignant transformation. Progression in grade of a glioma is reflected in the progressive decrease in the N-acetylaspartate and myo-inositol levels on the one hand and elevation in choline level up to grade III on the other. Malignant transformation of the glial tumors is also accompanied by the presence of lactate and lipids in MR spectra of grade III but mainly grade IV gliomas. It follows that MRS is a helpful method for detection of glioma regions with aggressive growth or upgrading due to favorable correlation of the choline and N-acetylaspartate levels with histopathological proliferation index Ki-67. Thus, magnetic resonance spectroscopy is also a suitable method for the targeting of brain biopsies.
  
  
  CONCLUSIONS
  Gliomas of each grade have some specific MRS features that can be used for improvement of the diagnostic value of conventional magnetic resonance imaging in non-invasive assessment of glioma grade.
authors.affiliation: International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Bulik
authors.forename: Radim
authors.initials: R
authors.lastname: Jancalek
authors.forename: Jiri
authors.initials: J
authors.lastname: Vanicek
authors.forename: Antonin
authors.initials: A
authors.lastname: Skoch
authors.forename: Marek
authors.initials: M
authors.lastname: Mechl
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D005910:Glioma / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007294:Inositol / Q000378:metabolism; D007773:Lactates / Q000378:metabolism; D050356:Lipid Metabolism / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D019635:Neurosurgical Procedures
chemical_list: D007773:Lactates; D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline