fig 6.

Acute and chronic infarcts.

A, Diffusion-weighted image with b = 1000 s/mm² demonstrates a high-signal lesion, consistent with acute infarct in the left corona radiata, and a low-signal area in the right periventricular white matter (arrow), consistent with a chronic infarct. A second low-signal lesion is seen anterior to the high-signal area in the left subcortical white matter.

B, Diffusion-weighted image at b = 2500 s/mm² shows increased contrast of the high-signal and two low-signal lesions.

C, Diffusion-weighted image at b = 3000 s/mm² also demonstrates the high- and low-signal areas more conspicuously than at b = 1000.

D, FLAIR image demonstrating the encephalomalacia and reactive gliosis associated with the two chronic strokes seen as low-signal lesions on a diffusion-weighted image, and increased signal in the lesion seen as high signal on a diffusion-weighted image.