text: <unk>  is defined as an episode of neurological dysfunction caused by focal cerebral, spinal, or retinal infarction.  Infarction of the central nervous system serves as the main pathogenetic mechanism implicated in the etiology of<unk> .  CNS Infarction refers to brain, spinal cord, or retinal cell death attributable to<unk> , based on:
  1. Pathological, imaging, or other objective evidence of cerebral, spinal cord, or retinal focal<unk>  injury in a defined vascular distribution; or
  2. Clinical evidence of cerebral, spinal cord, or retinal focal<unk>  injury based on symptoms persisting ≥24 hours or until death, and other etiologies excluded.
  CNS infarction also include:
  Hemorrhagic infarction ("hemorrhagic transformation of infarction", "hemorrhagic conversion of infarction") - This may occur spontaneously or due to antithrombotic or thrombolytic treatment.  They generally lack a mass effect, and are managed according to<unk>  recommendations.  There are two types:
  Time of onset is defined as when the patient was last awake and symptom-free or known to be “normal".
option_0: Ischemic stroke
option_1: Hemorrhagic stroke
option_2: Subarachnoid hemorrhage
option_3: Watershed stroke
option_4: Carotid artery dissection
option_5: Migraine
option_6: Stroke
option_7: Vertebral artery dissection