A patient presented with thunder clap headache. Followed by unconsciousness with progressive 3rd cranial nerve palsy
Extradual hemorrhage
Aneurysmal subarachnoid hemorrhage
Basilar migraine
Cluster Headache
Harrison's textbook of internal medicine 17th edition . *Sudden transient loss of consciousness may be preceded by brief moment of excruciating head ache ,but most patient first complain of head ache on regain the consciousness . *3rd cranial nerve palsy , associate with pupillary dilatation,loss of ipsilateral light reflex,focal pain above and behind the eye . Ref Harrison20th edition pg 2445
C.N.S