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FIG 4. Abnormally bright cortex in the early subacute period.
A, Axial T2-weighted image (4500/105/1) initially was interpreted as normal. A careful retrospective analysis raised the possibility of increased signal intensity and thickening of the cortex.
B, Corresponding high-strength diffusion-weighted image (0.8/123/1100) shows abnormal brightness preferentially involving the cortex.
FIG 5. Images of abnormal white matter obtained during the late subacute period (15–20 days).
A, Axial T2-weighted image (3300/105/1) shows no definite abnormalities. There is subtle and nonspecific increased signal intensity in the white matter.
B, Corresponding high-strength diffusion-weighted image (0.8/123/1100) shows abnormally bright white matter in centra semiovale and no definite cortical abnormalities.
FIG 6. Images of laminar necrosis obtained during the chronic period.
A, Axial T1-weighted image (550/15/1) shows linear brightness along the superior frontal, pre-central, and central gyri corresponding to the sequelae of laminar necrosis 22 days after cardiac arrest.
B, Axial high-strength diffusion-weighted image (0.8/123/1100), obtained inferior to the image shown in A (convexity diffusion images were degraded by magnetic susceptibility artifacts), shows normal results.
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