Abstract
Purpose
To evaluate single‐voxel proton magnetic resonance spectroscopy (SV‐MRS) and magnetic resonance spectroscopic imaging (MRSI) metabolite results in individuals with HIV dementia.
Materials and Methods
Twenty HIV‐positive (HIV+) individuals underwent SV‐MRS (TE 35 msec) and MRSI (TE 280 msec). Results were stratified according to serostatus, dementia severity, psychomotor speed performance, and functional impairment.
Results
HIV+ individuals with psychomotor slowing had an increased myoinositol/creatine (mI/Cr) ratio (0.63 vs. 0.45) in the frontal white matter using SV‐MRS and an increased choline (Cho)/Cr ratio (1.88 vs. 1.41) in the mesial frontal gray matter using MRSI compared to HIV+ individuals without psychomotor slowing. Using MRSI, subjects with HIV dementia also had a decreased N‐acetyl aspartate (NAA)/Cho ratio (1.55 vs. 2.53) compared to HIV+ individuals without cognitive impairment in the mesial frontal gray matter. Both techniques detected metabolite ratio abnormalities associated with abnormal functional performance.
Conclusion
SV‐MRS and MRSI offer complementary roles in evaluating individuals with HIV dementia. Short TE SV‐MRS measures mI, which may be elevated in early HIV dementia, whereas MRSI provides wider spatial coverage to examine specific regional changes. J. Magn. Reson. Imaging 2005;21:325–333. © 2005 Wiley‐Liss, Inc.