Carotid Web Misdiagnosis

Background: A carotid web (CW), an atypical fibromuscular dysplasia, is rare and may cause ischemic stroke. It is challenging to recognize a CW promptly and treat it accordingly. We report a case of an initially misdiagnosed CW.

Case description: A 48-year-old man with recurrent cerebral infarction was transferred to our hospital for bypass surgery. Imaging performed at our facility showed multiple old infarct lesions and cerebral tissue hypoperfusion in the occluded left middle cerebral artery territory. Bypass surgery was performed without perioperative complications. While searching for the cause of his stroke, we found a thin intraluminal filling defect along the posterior wall of the left carotid bulb just beyond the carotid bifurcation on sagittal maximal intensity projection images, axial thin-cut images, and volume rendering images. The defect was diagnosed as a CW. It was also detected on follow-up ultrasonography. Owing to our initial unawareness, we did not photograph the carotid bulb during preoperative digital subtraction angiography and postoperative computed tomography angiography. Although the patient was treated with bypass, the persistence of the factors underlying the CW may induce further thrombosis and subsequent occlusion of his ipsilateral anterior cerebral artery.

Conclusions: Clinicians should be aware of CW as a potential cause of ischemic stroke. Head and neck computed tomography angiography is a reliable imaging method to detect CWs.