title: Posterior circulation ischemia in patients with fetal-type circle of Willis and hypoplastic vertebrobasilar system.
abstract: Little attention has been given to the fetal-type posterior circle of Willis (FTP) in the literature; also symptomatic basilar artery (BA) hypoplasia has been rarely reported. We aimed to illustrate that the association of a hypoplastic vertebrobasilar system (VBS) with the FTP may lead to posterior circulation ischemia. Magnetic resonance imaging and three-dimensional time-of-flight magnetic resonance angiography were performed in 88 consecutive patients with ischemic stroke or TIA in the VBS. Thirteen patients were identified with either stroke or TIA in the context of a hypoplastic VBS and a fetal origin of the posterior cerebral arteries. All patients had unilateral or bilateral FTP, hypoplastic BA and at least one hypoplastic vertebral artery. Transcranial color-coded duplex revealed decreased flow velocity and increased pulsatility index along the BA. A hypoplastic VBS may be accompanied by the FTP and its simultaneous occurrence can predispose to ischemic events in the posterior circulation.
authors.affiliation: Department of Neurology, Franz Tappeiner Hospital, Meran/o, via Rossini, 5, 39012 Meran/o, BZ, Italy. piergiorgio.lochner@asbmeran-o.it
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Lochner
authors.forename: Stefan
authors.initials: S
authors.lastname: Golaszewski
authors.forename: Francesca
authors.initials: F
authors.lastname: Caleri
authors.forename: Gunther
authors.initials: G
authors.lastname: Ladurner
authors.forename: Frediano
authors.initials: F
authors.lastname: Tezzon
authors.forename: Giulio
authors.initials: G
authors.lastname: Zuccoli
authors.forename: Raffaele
authors.initials: R
authors.lastname: Nardone
mesh_terms: D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000473:pathology*; D002560:Cerebrovascular Circulation; D002941:Circle of Willis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014711:Vertebral Artery / Q000503:physiopathology*