A 54 year old lady Sudden thunderclap headache, unconsciousness, ipsilateral, dilated pupil due to:- (LQ)
|A||Acute ischemia of midbrain|
|B||Acute aneurysmal hemorrhage|
|D|| Brain stem encephalitis
Acute aneurysmal hemorrhage
Subarachnoid hemorrhage (SAH) renders the brain critically ill from both primary and secondary brain insults. Excluding head trauma, the most common cause of SAH is rupture of a saccular aneurysm. Other causes include bleeding from a vascular malformation (arteriovenous malformation or dural arterial-venous fistula) and extension into the subarachnoid space from a primary intracerebral hemorrhage.