Creutzfeldt-jakob disease involvement of rolandic cortex: a quantitative apparent diffusion coefficient evaluation

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Sporadic Creutzfeldt-Jakob disease (sCJD) typically shows reduced water diffusivity in cerebral gray matter.
• Previous studies suggested sparing of the primary sensorimotor cortex (Rolandic cortex) in early sCJD.
• The reason for this apparent sparing on MRI was unclear, possibly due to unknown cortical features or reduced image conspicuity.

Purpose of the Study:

• To investigate if the Rolandic cortex is pathologically spared or if signal abnormalities are less conspicuous on diffusion-weighted MRI in early sCJD.
• To quantitatively assess water diffusivity in the Rolandic cortex using apparent diffusion coefficient (ADC) analysis.

Main Methods:

• Apparent diffusion coefficient (ADC) maps were generated from echo-planar diffusion-weighted images (epiDWI) of 6 sCJD patients and 8 controls.
• Regions of interest were manually placed in the precentral gyri, superior frontal gyri, postcentral gyri, supramarginal gyri, thalamus, putamen, and caudate nuclei.
• ADC and relative ADC (rADC) values were calculated for each region.

Main Results:

• Patients with sCJD exhibited significantly lower ADC values compared to controls across all measured brain areas (P <= 0.05).
• A trend of decreased ADC values in deep nuclei aligned with prior research.
• No significant difference in relative ADC (rADC) values was observed between sCJD and control groups in any region (P > 0.25).

Conclusions:

• Quantitative ADC measurements reveal reduced water diffusivity in the primary somatosensory cortex of early sCJD patients.
• The degree of diffusivity reduction is comparable to other neocortical areas.
• This quantitative finding contradicts the visual impression of Rolandic cortex sparing on diffusion-weighted MRI in early sCJD.