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RT Journal Article
SR Electronic
T1 High-Resolution MRA Cerebrovascular Findings in a Tri-Ethnic Population
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1661
OP 1669
DO 10.3174/ajnr.A8402
VO 45
IS 11
A1 Rehwald, Rafael
A1 Sudre, Carole H.
A1 Smith, Lorna
A1 Sokolska, Magdalena
A1 Tillin, Therese
A1 Atkinson, David
A1 Chaturvedi, Nishi
A1 Hughes, Alun D.
A1 Jäger, Hans Rolf
YR 2024
UL http://www.ajnr.org/content/45/11/1661.abstract
AB BACKGROUND AND PURPOSE: Incidental findings on brain MRI and variations of the circle of Willis (CoW) are relatively common among the general population. Ethnic differences have been described before, but few studies have explored the prevalence of incidental intracranial cerebrovascular findings and CoW variants in the setting of a single multiethnic cohort. The purpose of this investigation was to describe both incidental cerebrovascular findings and the morphology of the CoW on high-resolution 3T TOF-MRA in a UK tri-ethnic population-based cohort and to present updated prevalence estimates and morphologic reference values.MATERIALS AND METHODS: We studied participants from the UK Southall and Brent REvisited study who underwent 3T brain MRI between 2014 and 2018. TOF-MRA images were assessed for the presence of incidental cerebrovascular findings and used to determine CoW anatomy.RESULTS: Seven hundred fifty participants (mean age, 71.28 [SD, 6.46] years; range, 46–90 years; 337 women), 322 White Europeans, 253 South Asians, and 175 African Caribbeans were included. Incidental cerebrovascular findings were observed in 84 subjects (11.2%, 95% CI, 9.0%–13.7%; 36 women; 42.86%, 95% CI, 32.11%–54.12%), with cerebral aneurysms being the most frequent followed by intracranial arterial stenoses with the highest prevalence among South Asians compared with White European (OR: 2.72; 95% CI, 1.22–6.08; P = .015) and African Caribbean subjects (OR: 2.79; 95% CI, 1.00–7.82; P = .051). Other findings included arteriovenous malformations and infundibula. The CoW was found to be more often complete in women than in men (25.22% compared with 18.41%, P = .024) and in African Caribbean (34.86%) compared with White European (19.19%) and South Asian (14.23%) subjects (P &lt; .001 each).CONCLUSIONS: Intracranial arterial stenoses were independently associated with ethnicity after adjusting for vascular risk factors, having the highest prevalence among South Asians. The prevalence of aneurysms was higher than that in previous population-based studies. We observed anatomic differences in the CoW configuration among women, men, and ethnicities.ACAanterior cerebral arteryAcomAanterior comunicating arteryCoWcircle of WillisCVMcerebral vascular malformationsICASintracranial arterial stenosesPCAposterior cerebral arteryPcomAposterior communicating artery