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What is A 45 years old man with AIDS presents with misperception, tiredness and memory loss. Which imaging feature ours a diagnosis of progressive multifocal leukoencephalopathy over HIV encephalopathy? and explain in detail?
HIV encephalopathy: Mild cerebral atrophy and diffuse symmetrical periventricular and deep white matter T2/FLAIR abnormality. PML: deep white matter altered signals that display low signal in T1, bright signal in T2 and FLAIR without significant enhancement after contrast administration. PML is oured over HIV encephalopathy when- Rapid progression of lesions. Hypointensity on T1 sequence. Involvement of subcoical U fibres Asymmetrical lesions Relative sparing of periventricular white matter