Central vestibular disease in a blue and gold macaw (Ara ararauna) with cerebral infarction and hemorrhage

J Avian Med Surg. 2014 Jun;28(2):132-42. doi: 10.1647/2012-069.

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.

Publication types

  • Case Reports

MeSH terms

  • Animals
  • Bird Diseases / pathology*
  • Cerebral Hemorrhage / pathology
  • Cerebral Hemorrhage / veterinary*
  • Cerebral Infarction / pathology
  • Cerebral Infarction / veterinary*
  • Fatal Outcome
  • Female
  • Magnetic Resonance Imaging
  • Psittaciformes*