Carotid webs produce greater hemodynamic disturbances than atherosclerotic disease: a DSA time–density curve study

Abstract

BackgroundCarotid webs (CaWs) are associated with ischemic strokes in younger patients without degrees of stenosis that are traditionally considered clinically significant.ObjectiveTo compare the hemodynamic parameters in the internal carotid artery (ICA) bulbar segment in patients with CaW with those in patients with atherosclerotic lesions using time–density curve (TDC) analysis of digital subtraction angiography (DSA) images.MethodsWe retrospectively assessed DSA images of 47 carotid arteries in 41 adult patients who underwent ICA catheter angiography for evaluation after ischemic stroke. Hemodynamic parameters, including full width at half maximum (FWHM) and area under the time–density curve (AUC) as proxies for increased flow stasis, were calculated using TDC analyses of a region of interest (ROI) in the ICA bulb immediately rostral to the web/atherosclerotic plaque, relative to a standardized ROI in the ipsilateral distal common carotid artery (eg, relative FWHM (rFWHM)). Hemodynamic parameters were compared using non-parametric Kruskal-Wallis tests. Logistic regression was used to predict CaW versus mild/moderate atherosclerosis for each hemodynamic parameter, adjusting for degree of stenosis.ResultsMean age of patients was 56.0±13 years, with 22 (53.7%) women. 17 CaWs, 22 atherosclerotic plaques (15 mild/moderate and 7 severe), and eight normal carotid arteries were assessed. Significant between-group differences were present in the relative total AUC (p<0.001), relative AUC at wash out (p=0.031), and relative FWHM (p=0.001). Logistic regression to predict CaW versus mild/moderate atherosclerosis showed that rAUC total had the highest predictive value (pAUC=0.96, 95% CI 0.90 to 1.00), followed by rFWHM (0.87, 95% CI 0.74 to 1.00), and rAUC WO (0.74, 95% CI (0.57 to 0.91).ConclusionCaW results in larger local hemodynamic disruption, characterized by flow stasis, than mild/moderate carotid atherosclerotic lesions, suggesting that CaWs may produce larger regions of thrombogenic flow stasis.

Symptomatic atherosclerotic plaque accompanied by carotid web

“…14 According to computational fluid dynamic analysis of the carotid web, more prominent flow disturbances, such as turbulent flow or stasis, were observed than in carotid atherosclerotic disease. 15,16,17 Especially low wall shear stress was observed in the large recirculation zone distal to the carotid web. 15,16 Although cervical atherosclerosis may develop coincidentally in our case with vascular risk factors, the carotid web can potentially cause atherosclerotic plaque at the expanded recirculation area with hemodynamic instability.…”

The Value of Contrast-Enhanced Ultrasound in the Evaluation of Carotid Web

“…CaW leads to lumen stenosis and produces greater hemodynamic changes than atherosclerosis of a similar degree of lumen stenosis ( 10 ). The shelf-like structures of the CaW alter the distal hemodynamic pattern ( 22 ), resulting in the formation of a superimposed thrombus at the vortex ( 16 ).…”

“…CaW is commonly associated with the occurrence of an ipsilateral cerebral infarction or transient ischemic attack (TIA) ( 9 ), suggesting its involvement in potential stroke mechanisms ( 3 ). CaW is prevalent in 1–7% of the population ( 10 ) and is more common in younger patients with cryptogenic stroke ( 3 ).…”

The carotid web: Current research status and imaging features

“…During the late venous phase, contrast agent retention was observed at the distal end of the carotid web ( Figure 1B ). Compared with atherosclerosis, the carotid web showed a lesser degree of stenosis on DSA ( Park et al, 2022 ). Despite its reliability and safety, DSA remains an invasive technique.…”