A case of progressive multifocal leukoencephalopathy (PML) with a clas
sic clinical presentation but with unusual pathological and radiograph
ic findings is reported. The pathology revealed evidence of prior hemo
rrhage, and imaging studies revealed focal cerebral atrophy as well as
contrast enhancement on MR scans. The contrast enhancement was visibl
e only by utilizing magnetization transfer pulses on T1-weighted scans
. The case report indicates that image criteria for PML may need to be
redefined in the future.