title: Central vestibular disease in a blue and gold macaw (Ara ararauna) with cerebral infarction and hemorrhage.
abstract: A 24-year-old female blue and gold macaw (Ara ararauna) was presented for an acute onset of left head tilt. On examination, the macaw was dehydrated and had a 120-degree left head tilt, decreased proprioception of the left pelvic limb, and intermittent vertical nystagmus. Results of hematologic testing and biochemical analysis revealed severe leukocytosis with lymphopenia and heterophilia and a high uric acid concentration. Radiographs showed bilateral intertarsal joint osteoarthritis and a healed ulnar fracture. Magnetic resonance imaging of the brain revealed focal T2 and fluid-attenuated inversion recovery hyperintense lesions in the right cerebral hemisphere and in the midbrain. The midbrain lesion showed susceptibility artifact on the T2* sequence, suggesting hemorrhage. In the T2* sequence, iron accumulation (as seen with hemorrhage) distorts the magnetic signal, resulting in the production of a susceptibility artifact, which can then be visualized as a region of hypointensity. The bird was hospitalized but died despite intensive care. Necropsy revealed multiple cerebral vascular lesions including an acute cerebral infarct, a ruptured midbrain aneurysm, and multifocal systemic atherosclerosis. To our knowledge, this is the first report of a cerebral aneurysm in a bird. This report correlates the clinical presentation, imaging, and histopathologic findings in a macaw with central vestibular disease and demonstrates how advanced imaging techniques can identify hemorrhagic lesions through the T2* sequence.
authors.forename: Claire
authors.initials: C
authors.lastname: Grosset
authors.forename: David Sanchez-Migallon
authors.initials: DS
authors.lastname: Guzman
authors.forename: M Kelly
authors.initials: MK
authors.lastname: Keating
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Gaffney
authors.forename: Linda
authors.initials: L
authors.lastname: Lowenstine
authors.forename: Allison
authors.initials: A
authors.lastname: Zwingenberger
authors.forename: Alex C
authors.initials: AC
authors.lastname: Young
authors.forename: Karen M
authors.initials: KM
authors.lastname: Vernau
authors.forename: Amberly M
authors.initials: AM
authors.lastname: Sokoloff
authors.forename: Michelle G
authors.initials: MG
authors.lastname: Hawkins
mesh_terms: D000818:Animals; D001715:Bird Diseases / Q000473:pathology*; D002543:Cerebral Hemorrhage / Q000473:pathology / Q000662:veterinary*; D002544:Cerebral Infarction / Q000473:pathology / Q000662:veterinary*; D017809:Fatal Outcome; D005260:Female; D008279:Magnetic Resonance Imaging; D011563:Psittaciformes