Dynamic magnetic resonance appearance of the vertebral dissecting aneurysm--case report

A dissecting aneurysm of the vertebral artery occurred in a 38-year-old male presenting with ischemic attacks. Vertebral angiography revealed irregular narrowing and dilatation of the right vertebral artery, and retention of the contrast medium. Routine T1-weighted magnetic resonance (MR) imaging demonstrated signal voids compatible with a patent but narrowed vertebral lumen surrounded by three intensity components at the abnormality location identified on the vertebral angiograms. Dynamic MR imaging demonstrated strong enhancement of these components on the early images. These findings were consistent with the false lumen of the dissecting aneurysm. The different signal intensities were thought to reflect the blood flow rate.