Abstract Body: Introduction: Carotid webs (CW) are rare shelf-like filling defects arising from the posterior wall of the internal carotid artery (ICA) bulb and are reportedly associated with a high risk of recurrent stroke, particularly in young patients. Limited awareness and understanding of CW make diagnosis and clinical research challenging.
Methods: We searched the radiology database from 6 hospitals within a health system between January 2021 and June 2024 for reports that included “web” in the diagnostic impression. These were reviewed by two experienced raters to determine whether a CW was present based on previously published criteria. Discrepancies were resolved by consensus with a third rater (a neuroradiologist or a stroke neurologist). Cases were categorized as confirmed, possible, or no CW (Figure 1). Confirmed CWs were defined as a shelf-like, thin, linear filling defect on the posterior wall of the ICA bulb within 3cm of the bifurcation, visible as a septum on axial view, and without calcification/atherosclerotic plaque adjacent to the filling defect on multiplanar reconstruction view. Possible CWs were defined as filling defects 3-4.5cm from the bifurcation, not on the posterior wall, not seen on the axial view, or accompanied by atherosclerotic plaque/calcification in the proximity of the suspected web. The remaining cases were classified as no CW. Baseline characteristics of those with confirmed CWs were compared to the remainder.
Results: Of the 373 patients screened, 233 were reviewed. Of these, 102 (44%) were classified as confirmed CW, 66 (28%) as possible CW, and 65 (28%) as no CW (Figure 2). Patients with confirmed CW were younger, predominantly female, and they were less likely to have history of hypertension and diabetes mellitus compared to those in the possible CW and no CW groups (Table 1). Confirmed webs were numerically most commonly associated with Black/African American race.
Conclusions: Our findings underscore the need for standardized definitions for the diagnosis of carotid webs, as less than half of the webs suspected on radiology reports met the criteria established in the literature. Establishing consistent criteria is essential for further investigating the natural history and designing clinical trials for this reportedly high-risk disorder.