Related Experiment Video
Updated: May 16, 2026
Mouse Models of Periventricular Leukomalacia
Published on: May 18, 2010
[Diffusion-weighted MR imaging characterization of progressive multifocal leucoencefalopathy (PML) lesions]
Joana Barata Tavares1, Ana F Geraldo, Lia Neto
1Serviço de Neurorradiologia, Centro Hospitalar Lisboa Norte, EP - Hospital de Santa Maria, Lisboa, Portugal.
Introduction:
Progressive multifocal leucoencefalopathy (PML) is a subacute demielinating disease of the Central Nervous System caused by the neurotropic virus John Cunningham (JC), common in immunodeficient patients, namely in HIV infection. PML encephalic lesions have a progressive nature that needs characterization and progressive study, especially for evaluating the therapeutic response.
Material And Methods:
The authors reviewed diffusion-weight MR imaging of PML lesions in four patients, characterizing the different lesional areas in DWI and ADC maps, and correlating these data with previous published studies, namely regarding histological correlation and lesion time course.
Results:
The four cases studied showed heterogeneity in DWI and ADC maps, with restriction in water diffusion in the periphery of each lesion.
Discussion/Conclusion:
Diffusion-weighted MR images allows characterization of PML lesions, highlighting their heterogeneity and asynchrony. These data allow important knowledge on lesions temporal evolution and treatment response.
Insights
Diffusion-weighted MRI reveals heterogeneous and asynchronous Progressive Multifocal Leukoencephalopathy (PML) lesions. This imaging technique aids in understanding lesion evolution and treatment response in JC virus-associated PML.
Area of Science:
- Neuroimaging
- Neuroradiology
- Infectious Diseases
Background:
- Progressive Multifocal Leukoencephalopathy (PML) is a demyelinating disease of the Central Nervous System caused by the John Cunningham (JC) virus.
- PML predominantly affects immunodeficient patients, particularly those with HIV infection.
- Characterizing PML encephalic lesions is crucial for monitoring disease progression and therapeutic efficacy.
Observation:
- Diffusion-weighted MRI (dMRI) and ADC maps were utilized to examine PML lesions in four patients.
- The study focused on characterizing distinct lesional areas within the brain.
- Data were correlated with existing literature, including histological findings and lesion temporal dynamics.
Findings:
- dMRI and ADC maps demonstrated significant heterogeneity across PML lesions.
- A key observation was the restriction of water diffusion in the peripheral regions of the lesions.
- These imaging features highlight the asynchronous nature of lesion development.
Implications:
- Diffusion-weighted MRI provides valuable insights into the characterization of PML lesions.
- The findings underscore the heterogeneity and asynchronous evolution of PML lesions.
- This advanced imaging approach can significantly contribute to understanding lesion temporal dynamics and assessing treatment responses in PML patients.
