title: Frontostriatal fiber bundle compromise in HIV infection without dementia.
abstract: BACKGROUND
  Quantitative fiber tracking derived from diffusion tensor imaging (DTI) was used to determine whether white matter association, projection, or commissural tracts are affected in nondemented individuals with HIV infection and to identify the regional distribution of sparing and impairment of fiber systems.
  
  
  METHODS
  DTI measured fractional anisotropy and diffusivity, quantified separately for longitudinal (lambdaL) diffusivity (index of axonal injury) and transverse (lambdaT) diffusivity (index of myelin injury), in 11 association and projection white matter tracts and six commissural tracts in 29 men and 13 women with HIV infection and 88 healthy, age-matched controls (42 men and 46 women).
  
  
  RESULTS
  The total group of HIV-infected individuals had higher diffusivity (principally longitudinal) than controls in the posterior sectors of the corpus callosum, internal and external capsules, and superior cingulate bundles. High longitudinal diffusivity, indicative of axonal compromise, was especially prominent in posterior callosal sectors, fornix, and superior cingulate bundle in HIV with AIDS. Unmedicated patients had notably high transverse diffusivity, indicative of myelin compromise, in the occipital forceps, inferior cingulate bundle, and superior longitudinal fasciculus. Pontocerebellar projection fibers were resistant to HIV effects as were commissural fibers coursing through premotor and sensorimotor callosal sectors.
  
  
  CONCLUSIONS
  This quantitative survey of brain fiber tract integrity indicates that even nondemented HIV patients can have neuroradiological evidence for damage to association and commissural tracts. These abnormalities were vulnerable to exacerbation with AIDS and possibly mitigated by HAART.
authors.affiliation: Neuroscience Program, SRI International, San Jose, California, USA.
authors.forename: Adolf
authors.initials: A
authors.lastname: Pfefferbaum
authors.forename: Margaret J
authors.initials: MJ
authors.lastname: Rosenbloom
authors.forename: Torsten
authors.initials: T
authors.lastname: Rohlfing
authors.forename: Carol A
authors.initials: CA
authors.lastname: Kemper
authors.forename: Stanley
authors.initials: S
authors.lastname: Deresinski
authors.forename: Edith V
authors.initials: EV
authors.lastname: Sullivan
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000473:pathology; D000328:Adult; D016880:Anisotropy; D019380:Anti-HIV Agents / Q000494:pharmacology; D001931:Brain Mapping / Q000379:methods; D003342:Corpus Striatum / Q000473:pathology; D003704:Dementia / Q000209:etiology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D015658:HIV Infections / Q000188:drug therapy / Q000473:pathology* / Q000523:psychology / Q000821:virology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000187:drug effects / Q000473:pathology*; D009434:Neural Pathways / Q000473:pathology; D010523:Peripheral Nervous System Diseases / Q000821:virology; D012959:Socioeconomic Factors; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents