[Possibilities in the differential diagnosis of brain neoplasms using the long and short time sequences of proton magnetic resonance spectroscopy]

Abstract

Currently to perform proton magnetic resonance spectroscopy (1H MRS) with single voxel spectroscopy (SVS) technique long and/or short echo time sequences are used in order to provide complementary information. PURPOSE: The aim of the study was to compare the usefulness of STEAM (time echo, TE, 20 ms) and PRESS (TE 136 ms) sequences in the evaluation of brain neoplasms. MATERIALS AND METHOD: 15 healthy volunteers and 19 patients with brain tumors were examined using 1, 5 T MR scanner. MRI was performed with a standard protocol for brain neoplasms. 1H MRS with the SVS technique was performed after magnetic resonance imaging (MRI) using STEAM 20 and PRESS 136 sequences (voxel size 1 to 8 cc). RESULTS: In the STEAM sequence besides basic metabolites visible in PRESS as N-acetylaspartate, choline and creatine peaks of myoinositol and glutamate were visualized. Data obtained with short TE sequences in conjunction with long TE data were useful and in 5 cases necessary to identify the tumor type. These results were confirmed by pathology. CONCLUSIONS: The use of short TE sequences enables to visualize metabolites important for the diagnosis and differentiation of the tumor type. The combined information drawn out from both long and short TE spectra is also important