Progressive multifocal leukoencephalopathy: diffusion-weighted imaging and pathological correlations

Neuroradiology. 2004 Jan;46(1):22-5. doi: 10.1007/s00234-003-1115-9. Epub 2003 Oct 31.


We examined MRI of two patients with progressive multifocal leukoencephalopathy (PML), including diffusion-weighted imaging (DWI), with calculation of apparent diffusion coefficients (ADC). The pathology findings of one patient were compared with those of MRI. The lesions had different ADC and DWI appearances, depending on the stage of the disease. Newer lesions and the advancing edge of large lesions had normal-to-low ADC and gave high signal on DWI. Older lesions and the centre of large lesions had increased ADC and gave low signal. High signal on DWI and low ADC mark the regions of active infection and cell swelling, distinguishing them from areas of reparative gliosis.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Aged
  • Cell Size
  • Diffusion Magnetic Resonance Imaging
  • Humans
  • Leukoencephalopathy, Progressive Multifocal / diagnostic imaging*
  • Leukoencephalopathy, Progressive Multifocal / pathology*
  • Male
  • Radiography