FIG 1.

Right-sided M1 segment MCA occlusion (arrow). ColorViz summation maps (upper row) show predominantly green vessels in the affected territory (arrowheads), indicating a 1-phase delay; The vessel extent is identical to that of the unaffected hemisphere. The findings are consistent with good pial artery filling and collateral flow. Corresponding conventional mCTA images are displayed in the lower row. The patient received intravenous alteplase, and follow-up MR imaging 24 hours after symptom onset (upper and lower right) shows infarction of the caudate head and lentiform nucleus only, with sparing of the cortex.