Diffusion-weighted imaging of intramural hematoma in vertebral artery dissection.

BACKGROUND AND PURPOSE: Dissections of the carotid and vertebral arteries can be detected by several imaging modalities, but there is yet no consensus on the most efficient and effective choice.

METHODS: We performed diffusion-weighted imaging (DWI) in four patients with vertebral artery dissection documented with T2- and T1-weighted axial magnetic resonance imaging (MRI), and conventional angiography. Intervals from the onset of headache to evaluation ranged from one day to two weeks.

RESULTS: All the patients showed high signal intensity within the affected vertebral artery on DWI.

CONCLUSION: The movements of water molecules are more or less restricted within the clots according to the stage of thrombus formation in arterial dissection. Our study may provide another potential imaging method in the difficult task of proving arterial dissection.