[Diffusion-weighted MRI in sporadic Creutzfeldt-Jakob disease].

Conventional MRI with T1, T2 and FLAIR sequences has an important role for the diagnosis of Creutzfeldt-Jakob disease, but the usual examination does not exclude the disease. The objective of this study is to report on the role of diffusion-weighted imaging (DWI) in the diagnostic strategy. From 2002 to 2006, four patients with a suspected diagnosis of sporadic Creutzfeldt-Jakob disease, which was retrospectively confirmed, underwent DWI. In all patients, MRI demonstrated high-signal intensities on FLAIR sequences and on spin-echo T2-weighted MRI, with restricted diffusion of caudate and lenticular nuclei. In one patient, DWI revealed cortical high-signal intensities that were not visualized on either FLAIR or T2-weighted MRI. In two other patients, MRI showed restricted thalamic diffusion, which is a classic sign of the new variant of the disease. Thus, thalamic involvement can be found in the sporadic form of the disease. It can be revealed on DWI and by apparent diffusion coefficient (ADC) mapping or detected only by ADC measurement.