Various Patterns of Perfusion-Weighted MR Imaging and MR Angiographic Findings in Hyperacute Ischemic Stroke

Case 10: 61-year-old man with hyperacute ischemic stroke with arterial occlusion and increased CBV.

A, T2-weighted image (3500/90) is normal except for small chronic lesion with hemosiderin rim in left basal ganglia.

B, 3D time-of-flight MR angiogram reveals occlusion of left internal carotid artery through M1 segment of the left MCA.

C, CBV map shows increased CBV throughout left MCA distribution.

D, CBV map shows irregular ROIs placed for measurement of CBV ratio and time–signal intensity curves between the region of increased CBV and contralateral normal region. Calculated CBV ratio was 1.23.

E, Time–signal intensity curves measured during passage of contrast material show delayed arrival time and delayed washout of the contrast material in left MCA distribution, suggesting collateral flow.

F, ^99mTc-HMPAO brain SPECT scan obtained during the hyperacute stage at approximately the same level as A and C reveals mild hypoperfusion throughout left MCA and anterior cerebral artery distribution.

G, Follow-up T2-weighted MR image (3500/90) obtained 2 days after the onset of symptoms is normal except for small chronic lesion in left basal ganglia.