Characterization of untreated gliomas by magnetic resonance spectroscopic imaging

The prognosis, choice of therapy, and management of adult gliomas are dependent upon the accurate diagnosis of tumor grade. The evaluation of tumor grade is performed by histological analysis of image-guided biopsy or of tissue samples obtained during surgical resection. This is a major problem because gliomas are known to be extremely heterogeneous, both in terms of the morphological characteristics of tumors with similar grade and in terms of the variability within individual lesions. Predicting which portion of the lesion is likely to be the most malignant and directing the surgeon to this location is critical for accurate diagnosis. Magnetic resonance imaging and spectroscopy are noninvasive imaging techniques that have been proposed for the evaluation of tumor grade in patients with untreated gliomas.