[Azygos anterior cerebral artery aneurysm in a patient with Noonan syndrome].

Noonan syndrome(NS)is a common, clinically and genetically heterogeneous condition characterized by distinctive facial features, short stature, congenital heart disease, and other comorbidities. However, there have been only a few case reports of cerebrovascular abnormalities in patients with NS. Especially, the cases of intracranial aneurysms with NS are very rare. In addition, comorbidities of azygos anterior cerebral artery(ACA)and NS have not been reported before now. We encountered such a rare case of azygos ACA unruptured aneurysm in patient with NS. The case was 64-year-old woman with NS complaining of gait disturbance. The three-dimensional CT angiography(3D-CTA)showed azygos ACA and an unruptured saccular aneurysm at the distal end of the A2 segment. An operation for this aneurysm was performed. We reviewed clinical features of NS with cerebrovascular disease such as aneurysm.