Pathologic correlates of diffusion MRI changes in Creutzfeldt-Jakob disease

Area of Science:

• Neuroimaging
• Neuropathology
• Prion Diseases

Background:

• Creutzfeldt-Jakob disease (CJD) is a fatal neurodegenerative disorder.
• Magnetic resonance imaging (MRI) shows characteristic changes in CJD, but their neuropathologic basis is unclear.
• Reduced apparent diffusion coefficient (ADC) and hyperintense T2-weighted signals are observed in specific brain regions.

Purpose of the Study:

• To investigate the neuropathologic correlates of antemortem ADC and T2-weighted MRI changes in CJD patients.
• To establish the relationship between diffusion changes and specific pathological markers.
• To understand the underlying causes of MRI abnormalities in CJD.

Main Methods:

• Diffusion-weighted imaging (DWI) and T2-weighted MRI were performed on 10 CJD patients and 10 controls.
• Postmortem neuropathologic assessment included gliosis, neuronal loss, spongiform changes, and PrP protein deposition.
• Semiquantitative analysis was conducted on 60 regions of interest (ROIs) across cortical and deep gray matter.

Main Results:

• Strong correlations were found between gliosis and neuronal loss in all ROIs.
• Spongiform changes correlated with gliosis and neuronal loss in the cortex, and with PrPSc load in both cortical and deep gray matter.
• ADC values significantly decreased with increasing spongiform change and PrPSc load in deep gray matter, and with all pathological scores in the cortex.

Conclusions:

• Antemortem reductions in ADC values in CJD are significantly correlated with spongiform changes observed postmortem.
• This correlation was particularly evident in the striatum and thalamus.
• The study links specific MRI findings to the neuropathologic hallmarks of CJD, enhancing diagnostic understanding.