The Role of Magnetic Resonance Spectroscopy in the Evaluation of Brain Glioma and its Grading

Abstract

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. In this review, we describe potential of MRS for grading of gliomas. Which showed Low-grade gliomas are generally characterized by a relatively high concentration of choline, and absence of lactate and lipids. The increase in degree of rise of choline concentration indicates higher-grade gliomas with advanced malignant transformation. Progression in grade of a glioma is reflected in the progressive increase in the choline as well as Cho/Cr ratio. 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 due to presence of central necrosis. 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 histopatholoical correlation. Thus, magnetic resonance spectroscopy is also a suitable method for the Most cases of brain gliomas showed heterogenous enhancement in conventional MRI. The specific spectrum of the glioma whether astrocytoma, anaplastic astrocytoma and glioblastoma multiform shows characteristic peak choline with/without additional resonances of lactate and lipids in examination of the central necrotic brain tumours however