Morphological characteristics of symptomatic and asymptomatic carotid webs

Abstract

OBJECTIVE Carotid webs (CWs) are an increasingly recognized source of recurrent stroke among young patients without conventional vascular risk factors. There have been no previous studies demonstrating that specific web morphological characteristics correlate with a higher stroke risk. The authors aim to report distinct morphological features of symptomatic and asymptomatic CWs. METHODS The authors performed a cross-sectional study of patients with CWs detected on CT angiography (CTA) of the neck. Patients were categorized based on whether or not they presented with stroke ipsilaterally and if it was likely to be attributable to their web. The following CW morphological variables were recorded and compared based on CTA: length, thickness, angle, and the proportion of carotid bulb lumen occupied by the web (web-to-bulb ratio [WBR]). RESULTS A total of 86 CWs were identified, 14 of which presented with stroke (16.3%). Patients presenting with stroke had webs that were significantly longer (4.18 mm vs 2.20 mm, p = 0.001) and were situated at more acute angles relative to the carotid wall (73.2° vs 94.9°, p = 0.004). Additionally, patients presenting with stroke had higher WBRs compared to the asymptomatic cohort (0.50 vs 0.36, p = 0.008). The optimal threshold associated with stroke was web length ≥ 3.1 mm (OR 15.2, 95% CI 3.73–61.8; p < 0.001), web angle ≤ 90.1° (OR 5.00, 95% CI 1.42–17.6; p = 0.012), and WBR ≥ 0.50 (OR 30.0, 95% CI 5.94–151; p < 0.001). CONCLUSIONS Patients with CWs that occupy more than half of the diameter of the carotid bulb lumen and are situated at acute angles relative to the carotid wall are more likely to present with acute ischemic stroke. Additional studies are needed to determine the long-term outcomes of these lesions.

Carotid webs: a review of pathophysiology, diagnostic findings, and treatment options

“…Tabibian et al15 suggested that a length of ≥3 mm, acute angle relative to the carotid wall, and greater than 50% CaW occupancy of the carotid bulb were associated with stroke. More recently, Perry da Camara et al corroborated these findings, showing that CaW length and volume are significantly associated with TIA or stroke 16.…”