PT  - JOURNAL ARTICLE
AU  - J.-h. Kim
AU  - K.-H. Chang
AU  - D.G. Na
AU  - I.C. Song
AU  - B.J. Kwon
AU  - M.H. Han
AU  - K. Kim
TI  - 3T <sup>1</sup>H-MR Spectroscopy in Grading of Cerebral Gliomas: Comparison of Short and Intermediate Echo Time Sequences
DP  - 2006 Aug 01
TA  - American Journal of Neuroradiology
PG  - 1412--1418
VI  - 27
IP  - 7
4099  - http://www.ajnr.org/content/27/7/1412.short
4100  - http://www.ajnr.org/content/27/7/1412.full
SO  - Am. J. Neuroradiol.2006 Aug 01; 27
AB  - BACKGROUND AND PURPOSE: Echo time (TE) can have a large influence on the spectra in proton MR spectroscopy (1H-MR spectroscopy). The purpose of this study was to comparatively assess the diagnostic value of 3T single-voxel 1H-MR spectroscopy with short or intermediate TEs in grading cerebral gliomas.METHODS: Single voxel 1H-MR spectroscopy was performed at 3T in 35 patients with cerebral glioma. The spectra were obtained with both short (35 ms) and intermediate TEs (144 ms). Metabolite ratios of choline (Cho)/creatine (Cr), Cho/N-acetylaspartate (NAA), lipid and lactate (LL)/Cr and myo-inositol (mIns)/Cr were calculated and compared between short and intermediate TEs in each grade. After receiver operating characteristic curve analysis, diagnostic accuracy for each TE in differentiating high-grade glioma from low-grade glioma was compared.RESULTS: At short TE, Cho/Cr and Cho/NAA ratios were significantly lower, and LL/Cr and mIns/Cr were significantly higher, compared with those at intermediate TE, regardless of tumor grade. Lactate inversion at intermediate TE was found in only 2 patients. At both TEs, there were significant differences in Cho/Cr and LL/Cr ratios between low- and high-grade gliomas. Diagnostic accuracy was slightly higher at short TE alone or combined with intermediate TE than intermediate TE alone (85.7% versus 82.9%).CONCLUSION: Metabolite ratios were significantly different between short and intermediate TE. Cho/Cr and LL/Cr ratios at either TE were similarly useful in differentiating high-grade gliomas from low-grade gliomas. If only a single spectroscopic sequence can be acquired, short TE seems preferable because of poor lactate inversion at intermediate TE on 3T single-voxel 1H-MR spectroscopy.