Imaging in acquired immune deficiency syndrome dementia complex (AIDS dementia complex): a review

1. Since 1986, the AIDS dementia complex has been recognized increasingly as a significant sequela of HIV infection. Though the pathogenesis remains poorly characterized and the diagnosis is one of exclusion, research utilizing various imaging techniques has resulted in greater understanding of the progressive character of ADC. 2. CT and MR studies have revealed general atrophy, atrophy of the basal ganglia, and white matter lesions that appear to increase in severity with progression of HIV infection. 3. CT and MR are relatively insensitive to the presence of clinical dementia, neurological signs, or positive findings on neuropsychological tests. In addition, they show poor correlation with histopathologic findings. 4. PET, SPECT, and MRS show the greatest sensitivity to changes wrought by primary HIV infection of the CNS and thus the greatest potential for early diagnosis of ADC. 5. PET, SPECT, and MRS show involvement of the basal ganglia, bloodflow abnormalities, and metabolite disturbances in HIV-seropositive subjects without findings on examination or neuropsychological tests.