A 42 year-old woman developed headaches and slowly progressive weakness affecting the left side over two months.
Axial MRI scan. (Left) T1-weighted image; (Right) T2-weighted image. Note the large mass in the right frontal/temporal lobes associated with mass effect and vasogenic edema. On T2, the mass is both white and dark representing partially clotted blood (dark is the deoxyhemoglobin, where the bright is methemoglobin. This is a giant aneurysm of the middle cerebral artery which is mostly thrombosed.
The Electronic Curriculum is copyrighted 1998, Case Western Reserve University School of Medicine.