title: Pure midbrain ischemia and hypoplastic vertebrobasilar circulation.
abstract: Isolated midbrain infarction is rare and little is known about etiology and patient's long-term follow up. We aimed to describe the clinical features, the causative diseases and the outcome of patients with isolated midbrain infarction who were admitted to our center, focusing on vascular abnormalities of posterior circulation. All patients with first acute ischemic stroke limited to the midbrain were included and their demographic features, neurological symptoms, neuroimaging data, and cardiovascular risk factors were recorded. Functional outcome, using modified Rankin scale, was assessed at discharge and at the 3 month follow up evaluation. We found nine patients with acute isolated midbrain infarction, representing 0.61 % of all ischemic stroke admitted to our center. The most common cause of stroke was small-vessel disease (88.8 %). At stroke onset, none of the patients had consciousness disturbances, and four patients (44.4 %) had gait impairment, five patients (55.5 %) presented with diplopia due to involvement of the third nerve or fascicular type of third-nerve palsy, seven patients (77.7 %) had vascular anomalies of vertebrobasilar circulation: the most frequent was vertebral artery hypoplasia [four patients (44.4 %)]. At follow up evaluation, seven patients (77.7 %) had a good functional outcome and no patients experienced recurrence of cerebrovascular events. As isolated midbrain infarction is uncommon, specific ocular motor signs, mainly third-nerve palsy, may help to identify and localize the mesencephalic infarct. Abnormalities in vertebrobasilar circulation, such as hypoplastic basilar or vertebral artery, are frequently associated with isolated midbrain ischemia. The hypoplastic vertebrobasilar system may predispose to posterior ischemic stroke.
authors.affiliation: Stroke Unit, U.O. Neurologia Vascolare, Spedali Civili di Brescia, P.le Spedali Civili, 1, Brescia, Italy, nicgilbe@tin.it.
authors.forename: Nicola
authors.initials: N
authors.lastname: Gilberti
authors.forename: Massimo
authors.initials: M
authors.lastname: Gamba
authors.forename: Angelo
authors.initials: A
authors.lastname: Costa
authors.forename: Veronica
authors.initials: V
authors.lastname: Vergani
authors.forename: Raffaella
authors.initials: R
authors.lastname: Spezi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Pezzini
authors.forename: Irene
authors.initials: I
authors.lastname: Volonghi
authors.forename: Dikran
authors.initials: D
authors.lastname: Mardighian
authors.forename: Roberto
authors.initials: R
authors.lastname: Gasparotti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Padovani
authors.forename: Mauro
authors.initials: M
authors.lastname: Magoni
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008636:Mesencephalon / Q000098:blood supply* / Q000473:pathology; D008875:Middle Aged; D063868:Patient Outcome Assessment; D020521:Stroke / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D014715:Vertebrobasilar Insufficiency / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology