3D mapping of ventricular and corpus callosum abnormalities in HIV/AIDS.
OBJECTIVE
40 million people worldwide are now infected with HIV/AIDS, an illness that often leads to rapidly progressing dementia and death. Even so, little is known about how AIDS affects the brain. Using computational anatomy techniques, we mapped how AIDS impacts the corpus callosum (CC) and ventricular system, two systems that show prominent changes on MRI. We (1) identified regions with greatest differences between AIDS patients and healthy controls and (2) correlated specific 3D patterns of structural differences with measures of immune system deterioration and cognitive decline.


METHODS
51 3D brain MRI scans from 30 non-demented AIDS patients (age: 43.4 years +/- 7.6 SD) and 21 HIV-seronegative controls (age: 39.5 years +/- 12.2) were aligned to ICBM standard space. 3D surface mesh reconstructions of the lateral ventricles and CC were spatially averaged and compared across diagnostic groups. Structural alterations were correlated with viral load, T cell counts, and cognitive impairment.


RESULTS
Statistical maps revealed the 3D profile of ventricular expansion and callosal thinning in AIDS. Specific 3D ventricular changes were linked with immune system decline (CD4+ T cell counts; P < 0.001) and cognitive impairment (P < 0.009), but not viral load. Frontal horn maps distinguished AIDS patients from controls better than occipital and temporal horn measures. T cell decline linked with callosal thinning in anterior regions connecting frontal areas with greatest cortical atrophy.


CONCLUSIONS
These maps (1) reveal how brain changes in HIV/AIDS relate to immune decline and impaired cognition, and, after further validation and testing, (2) may offer possible neuroimaging markers for anti-viral drug trials, which gauge how well treatments oppose disease progression in the brain.
Thompson
Paul M
PM
Laboratory of Neuro Imaging, Dept. of Neurology, UCLA School of Medicine, 635 Charles E. Young Drive South, Suite 225E, Los Angeles, CA 90095-7332, USA. thompson@loni.ucla.edu
Dutton
Rebecca A
RA
Hayashi
Kiralee M
KM
Lu
Allen
A
Lee
Sharon E
SE
Lee
Jessica Y
JY
Lopez
Oscar L
OL
Aizenstein
Howard J
HJ
Toga
Arthur W
AW
Becker
James T
JT
D015526:AIDS Dementia Complex / Q000175:diagnosis* / Q000276:immunology; D000328:Adult; D001931:Brain Mapping; D018791:CD4 Lymphocyte Count; D003071:Cognition / Q000502:physiology; D003337:Corpus Callosum / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D020547:Lateral Ventricles / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D012016:Reference Values; D013223:Statistics as Topic