Single-voxel 1H PRESS at 4.0 T: precision and variability of measurements in anterior cingulate and hippocampus.
The precision [coefficient of variation or CV (%) = 100SD/X] of single-voxel point resolved spectroscopic data was characterized bilaterally, in anterior cingulate and in hippocampus, at 4.0 T in a healthy subject. Data acquisition was replicated 10 times after voxel repositioning and readjusting higher order shims. Precision measurements show that the scan-to-scan precision is better in anterior cingulate than in hippocampus, with an average CV of 9.2% (for total NAA, tCho and Cr) in anterior cingulate and 13.9% in hippocampus. Variability measurements made by the same method in 24 healthy subjects and in 29 schizophrenia patients showed that there is substantial biological variability in metabolite levels, even in healthy subjects. Simple calculations suggest that more than 200 subjects would be needed to detect a 5% difference in NAA between patients and controls.
Venkatraman
Talaignair N
TN
Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710, USA.
Hamer
Robert M
RM
Perkins
Diana O
DO
Song
Allen W
AW
Lieberman
Jeffrey A
JA
Steen
R Grant
RG
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D005260:Female; D006179:Gyrus Cinguli / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D018377:Neurotransmitter Agents / Q000032:analysis*; D011522:Protons; D015203:Reproducibility of Results; D018401:Sample Size; D012559:Schizophrenia / Q000175:diagnosis* / Q000378:metabolism*; D012680:Sensitivity and Specificity; D014018:Tissue Distribution
D015415:Biomarkers; D018377:Neurotransmitter Agents; D011522:Protons