[A case of spontaneous cervical internal carotid artery dissection]

Dissection of the extracranial carotid artery is a recognized cause of ischemia, particularly in young persons who present with acute neurologic deficits, both transient and permanent. We describe a patient with a spontaneous dissection of the cervical internal carotid artery (ICA). A previously healthy 24-year-old man was hospitalized because of a sudden onset of right hemiparesis and consciousness disturbance. In reality, right cervical pain preceded this attack. The first brain MRI revealed a cerebral infarction in the right cerebral hemisphere including basal ganglia. A conventional angiography was performed 1 week later. The following angiographic picture was considered to be consistent with the diagnosis of cervical artery dissection: gradually tapered occlusion beginning distal to the carotid bifurcation. And MRA revealed the same finding. A cervical MRI revealed as an eccentric signal void (corresponding to the residual lumen) surrounded by a semilunar hyperintensity (corresponding to the mural hematoma) on T1- and T2-weighted images. Dynamic CT scan (D-CT) revealed an eccentric and crescent contrast enhancement (corresponding to the residual lumen) surrounded by a relative hypodensity compared with muscle (corresponding to the mural hematoma), itself surrounded by a thin annular enhancement. From these results, we diagnosed this patient with ICA occlusion for dissection of the extracranial carotid artery. But we decided this case contraindication of anastomosis because he had had a major stroke. Our findings suggest that MRA, cervical MRI and DCT provide early recognition of internal carotid artery dissection and monitoring of its resolution. Thus, these studies may guide clinical decisions according to the development of the dissection.