Abstract Number ‐ 232: Carotid Webs as an Under‐Reported Etiology of Acute Ischemic Stroke – Current Diagnostic Challenges

Abstract

Introduction Carotid webs are anatomical variants in the internal carotid artery vasculature that predispose patients to stroke. As of now, optimal treatment has yet to be established given the lack of large, randomized trials. Part of this stems from the fact that carotid webs remain under‐recognized sources of ischemic stroke despite a high rate of reoccurrence. Herein, we aim to shed light on the diagnosis with our respective center’s experience as well as discuss diagnostic challenges associated with carotid webs. Methods We present a case of a 40‐year‐old male with no past medical history who presented to our center after having developed sudden onset left sided weakness and sensory loss, a left homonymous hemianopia, and dysarthria. Vessel imaging confirmed a right middle cerebral artery occlusion, specifically in the M2 segment, in the setting of a right carotid web. Results Once intracerebral hemorrhage was ruled out, tissue plasminogen activator was administered, with improvement in neurologic exam. Mechanical thrombectomy was thus deferred. Review of the MRI brain showed that in addition to an infarct in the right subinsular white matter region, there were scattered multifocal right hemispheric acute to early subacute infarcts raising concern for an underlying embolic etiology. While the right M2 occlusion looked like it had mainly resolved, a new focal non‐occlusive intraluminal thrombus was found in the right carotid bulb on CTA, MRA, and carotid ultrasound, just distal to a small transverse extraluminal carotid web (Figure 1). The decision was made to take the patient for right carotid stenting given that the carotid web served as a high‐risk lesion. A stent was placed in the right carotid artery with no complications, and the patient was continued on dual antiplatelet therapy. Upon being seen in outpatient clinic after discharge, patient had NIHSS score of 0, with no residual deficits, and was continued on DAPT and a statin for secondary stroke prevention. Conclusions Knowing that patients with carotid webs are at increased risk for stroke, recognition and accurate diagnosis of webs is crucial for appropriate treatment. Diagnostic challenges of carotid webs should be highlighted to prevent misdiagnosis. These include heightened awareness of the patient population that is most at risk, radiographic mimics, location of the lesion as a confounder, and rule out of other stroke etiologies. Prompt recognition of this high‐risk vascular lesion using multiple imaging modalities at different time points during the patient’s admission allowed for treatment of the underlying etiology of his stroke. By increasing awareness on the appropriate diagnostic approach for carotid webs, more information can be garnered to elucidate optimal treatment strategies.