NEAR-OCCLUSION IS A COMMON VARIANT OF SYMPTOMATIC ≥50% CAROTID STENOSIS: PROSPECTIVE STUDY AND SYSTEMATIC REVEW (ID 519)
Abstract
Background And Aims
Symptomatic carotid near-occlusion is described as rare and/or ≤10% of stenosis cases in reviews of near-occlusion. Recent studies have shown that near-occlusions are overlooked, on ultrasound due to high stenosis velocity, on computed tomography angiography (CTA) due to poor image interpretation. Studies requiring treatment are likely to have lower prevalence of near-occlusion than consecutive stroke unit-based studies. The aim was to assess the prevalence of near-occlusion among symptomatic ≥50% carotid stenosis and review the literature.
Methods
Prospective controlled single-center stroke-unit based study. Consecutive cases with symptomatic ≥50% carotid stenosis were examined with CTA. The CTAs were assessed for near-occlusion by two observers. A systematic literature review was performed with emphasis on how study design affects prevalence estimate.
Results
186 patients with symptomatic ≥50% carotid stenosis were included, 34% (n=63, 95%CI 27-41%) had near-occlusion. Inter-rater kappa was 0.71. The average prevalence of near-occlusion among symptomatic ≥50% carotid stenosis was higher in studies that were consecutive, based in stroke units (not treatment series) and used angiography (30%, range 27-34%) than studies that required treatment or were ultrasound-based (9%, range 2-10%, Figure).
Conclusions
Near-occlusion is common variant of symptomatic ≥50% carotid stenosis, both in the current study and in all previous studies without obvious bias. Studies that suggest that near-occlusion is rare have all had methodological issues.
Trial Registration Number
Not Applicable
