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European Radiology
Published in: European Radiology 1/2019

Open Access 01-01-2019 | Vascular-Interventional

Multidetector CT angiography of the Circle of Willis: association of its variants with carotid artery disease and brain ischemia

Authors: Andrea Varga, Giovanni Di Leo, Péter Vince Banga, Csaba Csobay-Novák, Márton Kolossváry, Pál Maurovich-Horvat, Kálmán Hüttl

Published in: European Radiology | Issue 1/2019

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Abstract

Purpose

(1) to estimate the prevalence of Circle of Willis (CoW) variants in patients undergoing carotid endarterectomy, (2) to correlate these variants to controls and (3) cerebral ischemia depicted by computed tomography (CT).

Materials and methods

After Institutional Review Board approval, data of 544 carotid endarterectomy patients (331 males, mean age 69±8 years) and 196 controls (117 males, mean age 66±11 years) who underwent brain CT and carotid CT angiography (CTA) were retrospectively analysed. Two observers independently classified each CoW segment as normal, hypoplastic (diameter <0.8 mm) or non-visualized. Four groups of CoW variants based on the number of hypoplastic/non-visualized segments were correlated with clinical data (ANOVA, χ2 and multivariate logistic regression analysis). Intra- and inter-observer agreement was estimated using Cohen κ statistics.

Results

High prevalence of CoW variants (97%) and compromised CoW (81%) was observed in the study group and significant difference was found in the distribution of CoW variants compared to controls (p<0.001), internal carotid artery (ICA) stenosis being the only independent predictor of CoW morphology (p<0.001). Significant correlation was found between CoW configuration and brain ischemia in the study group (p=0.002). ICA stenosis of ≥90% was associated to higher rate of ipsilateral A1 hypoplasia/non-visualization (p<0.001). Intra- and inter-observer agreement was from substantial to almost perfect (Cohen κ=0.75–1.0).

Conclusion

Highly variable CoW morphology was demonstrated in patients undergoing endarterectomy compared to controls. Likely compromised CoW in relation to cerebral ischemia was observed in a large cohort of carotid endarterectomy subjects.

Key points

• CoW variant distribution significantly differed in the study and control groups (p<0.001).
• ICA stenosis was the only independent predictor of CoW morphology (p<0.001).
• Severely compromised CoW configuration showed significant association with brain ischemia (p=0.002).
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Metadata
Title
Multidetector CT angiography of the Circle of Willis: association of its variants with carotid artery disease and brain ischemia
Authors
Andrea Varga
Giovanni Di Leo
Péter Vince Banga
Csaba Csobay-Novák
Márton Kolossváry
Pál Maurovich-Horvat
Kálmán Hüttl
Publication date
01-01-2019
Publisher
Springer Berlin Heidelberg
Published in
European Radiology / Issue 1/2019
Print ISSN: 0938-7994
Electronic ISSN: 1432-1084
DOI
https://doi.org/10.1007/s00330-018-5577-x

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