Circle of Willis anomalies in Turner syndrome: Absent A1 segment of the anterior cerebral artery

Abstract

Purpose: Turner syndrome (TS) is the most common sex chromosome disorder in women and is associated with a higher than expected death rate secondary to cerebrovascular disease, including stroke. This study evaluates the cerebral vascular anatomy of individuals with TS. Methods: Twenty-one women with TS had brain magnetic resonance angiography (MRA). These MRAs were evaluated in a blinded manner with a control group of 25 men and 25 women who had MRA imaging for multiple indications including migraine headaches, psychiatric disorders, and seizures. Results: Twenty-nine percent of women with TS were missing an A1 segment of the anterior cerebral artery (ACA) compared to 0% in the control group (p <.001). There were no other significant differences in the circle of Willis (COW) in women with TS compared with the control group. A complete COW was found in 3 of 21 (14%) of women with TS and 12 of 47 (26%) controls (p =.36). Conclusion: Women with TS have a significantly different intracranial vascular anatomy, specifically the absence of the A1 segment of the ACA when compared to male and female controls. More research in brain imaging in women with TS and stroke and other cerebrovascular diseases is needed to determine the clinical significance of this anomaly.