Presentation
Five day history of visual field change, left upper limb numbness, and incoordination in left upper limb.
Patient Data
There is dissection of the internal carotid artery below the skull base with a large medially projecting pseudoaneurysm measuring up to 1.2 cm in maximum dimension. The mural hematoma extends into the carotid canal but not convincingly into the cavernous sinus. The is no definite intradural extension and no luminal irregularity in the intracranial vessels to suggest intradural extension. The intracranial vessels opacity normally.
The left common and internal carotid arteries opacify normally. The vertebral arteries are codominant. Aortic arch anatomy is conventional. Cervical spine alignment normal. No suspicious bone lesions.
Patchy, predominantly cortical, foci of diffusion restriction scattered through the right frontal, parietal, posterior temporal, and occipital lobes in keeping with acute infarct. The largest region of infarct is in the right parietooccipital lobe.
Case Discussion
Dissection of the right internal carotid artery below the skull base with a large pseudoaneurysm. The dissection extends into the carotid canal but with no definite intradural extension.
ICA dissection is a cause of stroke. Extracranial ICA dissection is more common. Intracranial extension must be assessed for as these have a much high rate of subarachnoid hemorrhage due to the media and adventitia being much thinner than in the extracranial vessel.