Type:
Educational Exhibit
Keywords:
Ischaemia / Infarction, Audit and standards, MR-Diffusion/Perfusion, CT, Neuroradiology brain
Authors:
Z. Hussein, T. Ashraf; Pilgrim Hospital, Boston/UK
DOI:
10.1594/ecr2013/C-1094
Background
Ischemic Stroke cause edema,
or swelling of the brain,
which develops within minutes of the insult.
Edema is associated with reductions in the apparent diffusion coefficient of water and These changes occur well before they can be detected by conventional T2-weighted MRI and CT scan
These changes represent variations in the random motion of water molecules in tissues.
They are expressed,
in diffusion-weighted images,
as changes in MRI signal intensity or as variations in the apparent
diffusion coefficient (ADC) of water.
Acute brain lesions like ischemic stroke are associated with reduced water diffusion,
they can be detected bright areas of signal hyperintensity in DW images and dark areas of signal hypointensity in ADC maps.