<unk>  is defined as rapidly developing clinical signs of neurological dysfunction attributable to a focal collection of blood within the brain parenchyma or ventricular system that is not caused by trauma.  It is important to note that only non-traumatic causes of CNS hemorrhages are classified as stroke.<unk>  consists of:
Intracerebral Hemorrhage (ICH)
This is defined as a focal collection of blood within the brain parenchyma or ventricular system that is not caused by trauma.  Therefore, it consists of:
1. Intraparenchymal hemorrhage
2. Intraventricular hemorrhage
3. Parenchymal hemorrhages following CNS infarction
Subarachnoid Hemorrhage (SAH)
This is defined as bleeding into the subarachnoid space (the space between the arachnoid membrane and the pia mater of the brain or spinal cord).  This consists of:
1.  Aneurysmal SAH
2.  Non-aneurysmal SAH
Time of onset is defined as when the patient was last awake and symptom-free or known to be “normal".
Hemorrhagic stroke
Ischemic stroke
Subarachnoid hemorrhage
Stroke
Watershed stroke
Intracerebral hemorrhage
Carotid artery dissection
Brain ischemia