A multicenter study of two magnetic resonance spectroscopy techniques in individuals with HIV dementia.
OBJECTIVE
To evaluate single-voxel proton magnetic resonance spectroscopy (SV-MRS) and magnetic resonance spectroscopic imaging (MRSI) metabolite results in individuals with HIV dementia.


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.


CONCLUSIONS
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.
Sacktor
Ned
N
Department of Neurology, Johns Hopkins Bayview Medical Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21224, USA. sacktor@jhmi.edu
Skolasky
Richard L
RL
Ernst
Thomas
T
Mao
Xiangling
X
Selnes
Ola
O
Pomper
Martin G
MG
Chang
Linda
L
Zhong
Kai
K
Shungu
Dikoma C
DC
Marder
Karen
K
Shibata
Dean
D
Schifitto
Giovanni
G
Bobo
Linda
L
Barker
Peter B
PB
D015526:AIDS Dementia Complex / Q000175:diagnosis*; D000328:Adult; D001923:Brain Chemistry; D003404:Creatinine / Q000032:analysis; D005260:Female; D006801:Humans; D007294:Inositol / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male
D007294:Inositol; D003404:Creatinine