Localized Single Voxel 1H MR Spectroscopy Toward Routine Clinical Use

Abstract

Purpose: To evaluate the automated 'H magnetic resonance spectroscopy (' H -MRS) method for a routine clinical use , various regions of the normal human brain were examined for regional variations , the reproducibility, and the quality control ofthe spectral data . Materials and Methods: localized ' H -MRS was performed in a GE 1.5T SIGNA MRI/MRS system using the automated method (PROton Brain Exam: PROBE). Six regions of the human brain from normal volunteers (N=25, age=23 -65) were examined: Occipital gray matter, parietal white matter, frontal white matter, pons, cerebellum , and basal ganglia regions. STEAM was used as the localization method with the f 이 lowing parameters: TE=30msec, TR=3.0sec, AVG=48 AVG , NEX= 2, Spectral Width (SW)=2500 Hz, Size (SI)=2048 points (2K ), and the size of voxel = 7 -9 m l. The reproducibility and the quality control of the spectral data were evaluated.Results: For the 6 regions, the regional variation by the spectral patterns and the metabolites ratios relative to creatine was well demonstrated. Rates of the auto prescan success and the percentages of obtaining the acceptable quality spectra were high in the parietal white matter, occipital gray matter, and basal ganglia regions, and low inthe frontal white matter and pons regions.Conclusion: PROBE is a highly practical as well asreliable method to produce reproducible quality spectra that represent the regional metabolic variations in the human brain . PROBE can be used as a single spectroscopic exam or as an additional series to a routine brain MRI exam, which takes less than 10 minutes for acquisition of one spectrum. In order to obtain good quality spectra , a good qualitycontrol scheme ofthe MR instrument is mandatory.