Neurointerventional management of carotid webs associated with recurrent and acute cerebral ischemic syndromes

Abstract

Background: A carotid web can be defined as an endoluminal shelf-like projection often noted at the origin of the internal carotid artery (ICA) just beyond the bifurcation. Diagnosis of a carotid web as an underlying cause of recurrent ischemic stroke is infrequent and easily misdiagnosed as an atheromatous plaque. Surgery has traditionally been used to resect symptomatic lesions while there is no enough evidence supporting medical therapy as the sole management. To our knowledge there is only one report about carotid artery stenting (CAS) as a definite management of carotid web and no previous reports of acute large-vessel occlusions undergoing mechanical thrombectomy in the setting of carotid web as the etiology.

Case report: We report two cases: The first presented with recurrent ischemic stroke in the same arterial territory and the other with an emergent left middle cerebral artery (MCA) occlusion that underwent endovascular mechanical thrombectomy in which initial computed tomographic angiograms (CTA) suggested carotid web etiologies. Following confirmation with digital subtraction angiography (DSA), both patients ultimately underwent endovascular carotid stenting instead of surgical resection for definitive carotid web treatment.

Conclusions: Carotid webs are a rare cause of ischemic stroke in young and middle-aged adults that can readily be identified by CTA. Endovascular management may include emergent mechanical thrombectomy for large-vessel thromboembolic complications, and for definitive treatment with carotid stenting across the carotid web as an alternative to surgical resection and medical management for secondary stroke prevention.

Keywords: Carotid; recurrent; stent; stroke; web.

Figure 1.

(a) Reformatted left oblique CTA demonstrates a focal stenosis at the origin of the left ICA secondary to a shelf-like hypodense projection (white arrow) arising from the posterior wall, raising the possibility of a carotid web or noncalcified atheroma. (b) Left common carotid (CCA) anterior oblique DSA centered over the neck demonstrates a prominent curved triangular ridge on the postero-lateral aspect of the left ICA causing flow stagnation in the carotid bulb (black arrow) consistent with a carotid web. (c) Lateral CCA DSA demonstrates final results after angioplasty and stent deployment with no residual stenosis at the left ICA origin, and redundant contrast at the distal carotid bulb with expected thrombosis and vessel remodeling. (d) Color Doppler images demonstrate patent stent (arrow heads) across the distal CCA and proximal ICA with full color saturation and no residual/recurrent stenosis. CTA: computed tomographic angiogram; ICA: internal carotid artery; DSA: digital subtraction angiography.

Figure 2.

(a) Anteroposterior (AP) left ICA DSA demonstrates occluded left MCA at the mid-M1 segment (arrow head) with occlusion of the lateral lenticulostriate arteries, but robust collaterals from the left ACA. (b) AP left ICA DSA after mechanical thrombectomy with stent retrieval demonstrates successful recanalization of the left MCA and its inferior division, and slow antegrade flow into the superior division (TICI = 2b). (c) Reformatted left oblique CTA reveals a focal stenosis at the origin of the left ICA secondary to a shelf-like hypodense projection (white arrow), raising the possibility of carotid web or noncalcified atheroma. (d) Left CCA anterior oblique DSA confirms a sharp-edged triangular ridge on the posterolateral aspect of the left ICA (black arrow) consistent with a carotid web and a separate downstream segmental stenosis with pseudoaneurysm consistent with an iatrogenic dissection. (e) Left anterior oblique CCA DSA post-treatment demonstrates the Xact stent (black arrow) deployment across the left ICA origin and the Neuroform stent reconstruction and angioplasty across the iatrogenic dissection (arrow heads) with no residual stenosis. ICA: internal carotid artery; DSA: digital subtraction angiography; MCA: middle cerebral artery; ACA: anterior cerebral artery; TICI: Thrombolysis in Cerebral Ischemia score; CCA: common carotid artery.