POSTMORTEM MR-IMAGING OF LOBAR CEREBRAL INFARCTION WITH PATHO-LOGIC AND IN-VIVO CORRELATION

Postmortem magnetic resonance (MR) imaging features of different types of lobar cerebral infarction are correlated with the findings in gros s and histologic specimens, The postmortem findings are also correlate d with in vivo findings in similar cases selected from teaching files, In acute infarction, white matter vasogenic edema leads to high signa l intensity on T2-weighted images and blurring of the gray-white matte r junction, Petechial hemorrhage in the cortex results in inhomogeneou s signal intensity on T2-weighted images, In laminar necrosis, the hyp erintense cortex on T1-weighted images is due not to hemorrhage but po ssibly to necrosis and the presence of lipid-laden macrophages. In sub acute infarction, cortical edema and necrosis may cause the gyral patt ern of enhancement, Meningeal inflammation and early fibrosis are prob ably responsible for meningeal enhancement, In chronic infarction, gli osis and cystic malacia are responsible for the increased signal inten sity of white matter on T2-weighted images, Knowledge of the pathologi c features of cerebral infarction helps in understanding the MR imagin g findings.