Crossed cerebellar diaschisis detected by arterial spin-labeled perfusion magnetic resonance imaging in subacute ischemic stroke.

BACKGROUND: Crossed cerebellar diaschisis (CCD) was a common radiological phenomenon manifested as reduced blood flow and metabolism in the cerebellar hemisphere contralateral to a supratentorial cerebral lesion. The hypoperfusion and hypometabolism in the contralateral cerebellum in CCD was traditionally detected by positron emission tomography (PET) and single-photon emission computed tomography (SPECT). The present prospective study aimed to assess the detection of CCD in subacute stage ischemic stroke by arterial spin-labeling (ASL) perfusion technique with a 3.0-T magnetic resonance imaging (MRI) scanner. METHODS: ASL images were obtained from 46 patients with supratentorial ischemic stroke at subacute stage. Regional cerebral blood flow values in the cerebellar hemispheres were measured on a region of interest basis. RESULTS: Twenty-four of 46 (52%) patients showed CCD phenomenon by ASL-MRI method, which was in line with the PET/SPECT series. Infarctions in basal ganglia areas are prone to cause CCD. CONCLUSIONS: With advantages in easy acquisition and no radiation, ASL-MRI seems to be an ideal tool for the detection and follow-up of CCD.

Reduced cerebral blood flow in genetic prion disease with PRNP D178N-129M mutation: an arterial spin labeling MRI study.

The D178N mutation in the PRNP gene is associated with fatal familial insomnia and Creutzfeldt-Jakob disease (CJD). Typically, the D178N mutation associated with the 129M genotype is related to fatal familial insomnia while the same mutation associated with the 129V genotype is linked to familial CJD. We describe a D178N-129M haplotype in a patient with early, severe dementia and late-onset minor insomnia, mainly presenting as the CJD phenotype. Cerebrospinal fluid 14-3-3 protein was positive. Diffusion weighted imaging demonstrated widespread cortical ribbon-like high signal intensity, which was also seen in the basal ganglia bilaterally. Arterial spin labeling (ASL) MRI showed severe hypoperfusion in the cerebral cortex, basal ganglia and thalami but this was least marked in the thalami. Neuroimaging abnormalities were more prominent in the cerebral cortex than the thalamus, which was in line with the clinical picture of severe dementia rather than insomnia. ASL-MRI seems to be a useful tool for the detection and follow-up of perfusion changes in patients and asymptomatic carriers harboring the PRNP mutation.