A 73 year-old man presented with a headache and progressive weakness affecting the left arm which slowly progressed over 3 hours. |
Subacute Early Intracerebral Hemorrhage: (Left) T1-weighted
axial MRI; (Right) T2-weighted axial MRI. Note
that on the T1-weighted image, there is an area of hyperintense
signal in the right frontal
lobe. The same
area on the T2-weighted scan is dark with a surrounding bright signal.
This is the characteristic picture of a subacute early (3-7 days) hemorrhage on MRI. The hyperintense signal on the T1-weighted image with the dark (hypointense) signal on the T2-weighted image is the pattern seen with intracellular methemoglobin. The bright surrounding signal on the T2-weighted image is vasogenic edema. In this case, there is also old encephalomalacia in the left occipital lobe from a previous stroke. 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. |
Revised
11/11/06.
Copyrighted 2006. David C Preston.