Imaging of Carotid Dissection

Here, we describe the four primary imaging modalities for identification of carotid artery dissection, advantages, limitations, and clinical considerations. In addition, imaging characteristics of carotid dissection associated with each modality will be described.

Recent advances in etiopathogenesis describe the genetic factors implicated in cervical artery dissection. MRI/MRA (magnetic resonance angiography) with fat suppression is regarded as the best initial screening test to detect dissection. Advances in magnetic resonance imaging for the diagnosis of dissection include the use of susceptibility-weighted imaging (SWI) for the detection of intramural hematoma and multisection motion-sensitized driven equilibrium (MSDE), which causes phase dispersion of blood spin using a magnetic field to suppress blood flow signal and obtain 3D T1- or T2*-weighted images. Digital subtraction angiography (DSA) remains the gold standard for identifying and characterizing carotid artery dissections. Carotid artery dissection is the result of a tear in the intimal layer of the carotid artery. This leads to a "double lumen" sign comprised of the true vessel lumen and the false lumen created by the tear. The most common presentation of carotid artery dissection is cranial and/or cervical pain ipsilateral to the dissection. However, severe neurological sequelae such as embolic ischemic stroke, intracranial hemorrhage, and subarachnoid hemorrhage can also result from carotid artery dissection. Carotid artery dissection can be identified by a variety of different imaging modalities including computed tomographic angiography (CTA), MRI, carotid duplex imaging (CDI), and digital subtraction angiography (DSA).