Use of Magnetic Resonance Spectroscopy of the Brain to Differentiate Low Grade Glioma and its Clinical Relevance

Abstract

Background and purpose: Nuclear magnetic resonance (NMR) spectroscopic examination plays an important role in diagnosis of low grade gliomas. We compared the spectroscopic examination with the histopathological results of low grade gliomas concerning its reliability and their clinical relevance. Materials and methods: The charts of 29 patients with low grade gliomas were collected. Only in 19 cases of them an NMR-spectroscopic examination was performed. Due to choline, N-acetylaspartate (NAA) and lipid content the gliomas were classified into astrocytoma WHO II or III or in low or high grade gliomas. After stereotactic biopsy or neurosurgical removal histopathological examination was performed. Results: We found 18 astrocytomas WHO II and 1 oligodendroglioma WHO II at the histopathological examination. In the spectroscopic examination we found 13 low grade gliomas II and 6 high grade gliomas. 68.4% of the 19 low grade gliomas WHO II correspond to the spectroscopic examination. 6 cases showed high choline contents suitable for high grade glioma and one of them with very high choline content which correspond to a glioblastoma. These tumours were classified as low grade gliomas WHO II in the histopathological examination. Conclusion: We compared the NMR-spectroscopic findings with the histopathological results of the tumours. The actual spectroscopical method does not seem to be reliable enough in the diagnosis of low grade gliomas but can play an important role in assessing the clinical condition and follow-up. Whether the NMR-spectroscopic findings correlate with the clinical course better than with the histopathological findings remains to be clarified.