Abnormal diffusion-weighted magnetic resonance images in Creutzfeldt-Jakob disease.

BACKGROUND Traditional imaging methods, including computed tomography, routine magnetic resonance imaging (MRI), and magnetic resonance spectroscopy, have not been particularly useful in the diagnosis of Creutzfeldt-Jakob disease (CJD). Although abnormalities can be seen using these methods, the findings are evident only late in the disease or lack specificity or sensitivity. OBJECTIVE To describe abnormalities on diffusion-weighted MRIs in 4 patients with proven CJD. METHODS Diffusion-weighted MRIs were obtained on 4 patients with CJD as part of a routine MRI brain examination. RESULTS In all 4 patients, diffusion-weighted MRIs of the brain demonstrated bilateral hyperintensity in the basal ganglia. In 1 patient, the most conspicuous abnormality seen in diffusion-weighted images was in the thalamus. Two patients also demonstrated hyperintensity in the cerebral cortex on diffusion-weighted images. Only 2 of 4 patients demonstrated clear abnormalities on routine (non-diffusion-weighted) MRIs. Diffusion abnormalities were visible in 1 patient within 1 month of symptom onset. The findings were most conspicuous and extensive in the patient with the longest duration of symptoms (7 months). CONCLUSIONS Diffusion-weighted MRI might provide a noninvasive method of identifying patients with CJD. However, further investigations must be performed to determine the specificity of these findings for CJD.