FIG 4. Serial MRA images in the patient in Figure 3. Images show progressive improvement in vascular patency.

A and B, Examination 3. The bilateral A-1 segments have become equivalent in size and the distal left ICA is less tapered. A 2-mm stenosis of the proximal left A-1 and a 1-mm stenosis of the proximal left M-1 segments persist. Also noted are the resolution of the right A-1 and M-1 stenoses and the moyamoya vasculopathy with persistent short-segmental stenoses in the proximal left A-1 and M-1 segments. The right MCA appears to be more patent; small-vessel conspicuity is lost; and both PCOMs have become smaller, suggesting a slower rate of blood flow.

C and D, Examination 4. Persistent short segment stenoses of the proximal left A-1 and M-1 segments remain.