Recurrent episodes of hemiparesis and aphasia

Diffusion weighted imaging and apparent diffusion coefficient mapping are extremely sensitive techniques for the detection of acute infarction. 1 2 Increased signal on diffusion weighted imaging and low value on apparent diffusion coefficient mapping reflect the restricted Brownian motion of water molecules in the extracellular space of this patient's brain, which is probably a result of swelling of the cellular elements of the brain (cytotoxic oedema). In general, migration of emboli could be from artery to artery or from heart to artery. [...]it is important to look for the source or "donor site" of an embolism, as well as for information about the recipient vessel in brain parenchymal or vascular imaging. Note that the dark signals on diffusion weighted imaging and bright signals on apparent diffusion coefficient mapping in the left frontal subcortical area, as shown by the chain-like or a rosary-like pattern, indicate an old infarct in the internal borderzone vascular area between the superficial and deep perforating branches of the left anterior cerebral artery and middle cerebral artery. Long answer The computed tomography angiogram of the cervical portion of the carotid and vertebral arteries shows marked narrowing (high grade stenosis) of the left internal carotid artery 1 cm distal to the carotid bifurcation (arrowhead in fig 4A) and a filling defect suggestive of intraluminal thrombus in the distal part of the cervical left internal carotid artery (curved arrows in 4C, D, and F). Intracranial vascular stenosis seems to be more common in Asian stroke patients (for example, Japanese...