Dawson, Elliot T.

A carotid web is a shelf-like intraluminal filling defect typically arising from the posterolateral wall of the proximal internal carotid artery. It is recognized as a possible cause of ischemic stroke in young adults. However, its etiopathogenesis is controversial and remains to be fully elucidated. The authors report de novo formation of a carotid web from an intimal dissection documented on serial imaging studies. The findings in this case suggest that a focal intimal dissection could be the underlying cause of a carotid web. Lower shear stress at the posterolateral wall of the proximal internal carotid artery is hypothesized to be a predisposing factor and explains the predilection of a carotid web for this specific location.

We present a case of supraclinoid internal carotid artery dissection. Eleven months prior, the patient developed isolated periorbital pain and was diagnosed with giant-cell arteritis with iritis. The patient experienced recurrent spells concerning for transient ischaemic attacks and was transferred to our institution for endovascular intervention after head CT revealed an embolic infarct with a ‘dense middle cerebral artery sign.’ Digital subtraction angiography was negative for occlusion, instead demonstrating luminal stenosis and poststenotic dilatation. He subsequently experienced acute neurological decline secondary to massive subarachnoid haemorrhage. Non-invasive vascular imaging revealed an intimal flap and a pseudoaneurysm at the site of luminal stenosis, confirming our suspicion for intracranial carotid artery dissection. Given the moribund clinical state, the family opted to withdraw care, and he quickly expired.