A 55 year old man presented with focal seizures affecting the left body.
Axial MRI scans: (Left) T1-weighted; (Right) T2-weighted. Note on T1, there is an area of hyperintense signal in the right posterior frontal lobe. The same area on T2 is also bright. This is the characteristic picture of a subacute late (7-14 days) hemorrhage on MRI. The hyperintense signal on both T1 and T2 is the pattern seen with extracellular methemoglobin. The findings of blood on MRI are complex and depend on timing. To learn more, review the powerpoint slide show, Blood on MRI: Time-dependent Changes. In this case, the hemorrhage was due to a small venous angioma which bled.
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