Figure 4.

Images of a 72-year-old woman with occlusion of the left internal carotid and middle cerebral arteries. The premorbid modified Rankin scale (mRS) score of this patient was 0, and the National Institutes of Health Stroke Scale score at admission was 20. The diffusion-weighted imaging (DWI), susceptibility-weighted imaging (SWI), and multiphase MR angiography collateral map at 5 h and 25 min after symptom onset are shown. DWI shows acute infarct signals in both cerebral hemispheres. Acute infarction in the right cerebral hemisphere was considered to indicate another embolic infarction. SWI shows very prominent cortical and medullary veins in the left middle cerebral artery territory, representing very poor collateral status. The collateral-perfusion delay of more than one-half of the left middle cerebral artery territory persisted until the late venous phase on the MR angiography collateral map (MR acute ischemic stroke collateral score of 0: very poor collateral perfusion defined as collateral-perfusion delay/defect more than one-half of the ischemic MCA territory in the late venous phase regardless of perfusion status at previous phases). The patient underwent conservative treatment and died of malignant infarction.