Pilot Assessment of Brain Metabolism in Perinatally HIV-Infected Youths Using Accelerated 5D Echo Planar J-Resolved Spectroscopic Imaging.
OBJECTIVE
To measure cerebral metabolite levels in perinatally HIV-infected youths and healthy controls using the accelerated five dimensional (5D) echo planar J-resolved spectroscopic imaging (EP-JRESI) sequence, which is capable of obtaining two dimensional (2D) J-resolved spectra from three spatial dimensions (3D).


METHODS
After acquisition and reconstruction of the 5D EP-JRESI data, T1-weighted MRIs were used to classify brain regions of interest for HIV patients and healthy controls: right frontal white (FW), medial frontal gray (FG), right basal ganglia (BG), right occipital white (OW), and medial occipital gray (OG). From these locations, respective J-resolved and TE-averaged spectra were extracted and fit using two different quantitation methods. The J-resolved spectra were fit using prior knowledge fitting (ProFit) while the TE-averaged spectra were fit using the advanced method for accurate robust and efficient spectral fitting (AMARES).


RESULTS
Quantitation of the 5D EP-JRESI data using the ProFit algorithm yielded significant metabolic differences in two spatial locations of the perinatally HIV-infected youths compared to controls: elevated NAA/(Cr+Ch) in the FW and elevated Asp/(Cr+Ch) in the BG. Using the TE-averaged data quantified by AMARES, an increase of Glu/(Cr+Ch) was shown in the FW region. A strong negative correlation (r < -0.6) was shown between tCh/(Cr+Ch) quantified using ProFit in the FW and CD4 counts. Also, strong positive correlations (r > 0.6) were shown between Asp/(Cr+Ch) and CD4 counts in the FG and BG.


CONCLUSIONS
The complimentary results using ProFit fitting of J-resolved spectra and AMARES fitting of TE-averaged spectra, which are a subset of the 5D EP-JRESI acquisition, demonstrate an abnormal energy metabolism in the brains of perinatally HIV-infected youths. This may be a result of the HIV pathology and long-term combinational anti-retroviral therapy (cART). Further studies of larger perinatally HIV-infected cohorts are necessary to confirm these findings.
Department of Radiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Zohaib
Z
Iqbal
Department of Radiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Neil E
NE
Wilson
Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Department of Pediatrics, Torrance, CA, 90502, United States of America.|Department of Pediatrics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Margaret A
MA
Keller
Department of Pediatrics, Miller Children's Hospital at Long Beach, Long Beach, CA, 90806, United States of America.
David E
DE
Michalik
Department of Pediatrics, Children's Hospital Los Angeles, Los Angeles, CA, 90027, United States of America.
Joseph A
JA
Church
Department of Pediatrics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Karin
K
Nielsen-Saines
Department of Pediatrics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Jaime
J
Deville
Department of Radiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Raissa
R
Souza
Department of Behavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
Mary-Lynn
ML
Brecht
Department of Radiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095, United States of America.
M Albert
MA
Thomas
D015526:AIDS Dementia Complex / Q000378:metabolism / Q000473:pathology; D000293:Adolescent; D000465:Algorithms; D019380:Anti-HIV Agents / Q000009:adverse effects / Q000627:therapeutic use; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D016022:Case-Control Studies; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D017352:Echo-Planar Imaging / Q000379:methods* / Q000706:statistics & numerical data; D004734:Energy Metabolism; D005260:Female; D059907:Functional Neuroimaging / Q000379:methods* / Q000706:statistics & numerical data; D018698:Glutamic Acid / Q000378:metabolism; D015658:HIV Infections / Q000188:drug therapy / Q000378:metabolism* / Q000635:transmission; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D010865:Pilot Projects; D055815:Young Adult
D019380:Anti-HIV Agents; D001224:Aspartic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline