1. Typical supratentorial right frontal cPML in an HIV-positive patient.
Typical supratentorial right frontal cPML in an HIV-positive patient. A, On DWI, the lesion shows typical restricted diffusion along the advancing edge posteriorly (arrows) and facilitated diffusion centrally. B, On the ADC map, ADC value is low at the posterior advancing edge (arrow) and high at the center of the lesion. C, The lesion typically involves the subcortical U-fiber and is hypointense (relative to gray matter) on the T1-weighted sequence. Note the absence of mass effect from this moderate-sized lesion. D, There is no enhancement of the lesion on the postcontrast T1-weighted sequence. E, On the FLAIR sequence, there is hyperintensity in most parts of the lesion. Note the inversion of the FLAIR high signal anteriorly (arrow) due to intralesional cystic change. F, On the T2-weighted sequence, the entire lesion is hyperintense. Note the adjacent anterior cortex is relatively spared (arrow). G, On perfusion imaging, cerebral blood volume of the lesion is lower (arrow) than that of the contralateral white matter.
A.K. Bag et al. AJNR Am J Neuroradiol 2010;31:
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