Bilateral periventricular and deep white matter relatively symmetric T2/FLAIR hyperintensity present that extends into the right cerebral peduncle, pons and medulla. The areas of abnormality demonstrate no evidence of mass effect, diffusion restriction or mass effect. Mild diffuse atrophy.
Conclusion: Mild cerebral atrophy and diffuse symmetrical periventricular and deep white matter T2/FLAIR abnormality extending into the left pons, in the setting of HIV infection without treatment and dementia type symptoms, findings would likely be in keeping with HIV encephalopathy. The Less likely differential would be CMV infection. Progressive multifocal leukoencephalopathy (PML) would only be expected to be seen in patients with treatment.