What's the difference between a aneurysm and non aneurysmal sah ?

First: Sub arachnoid hemorrhage (sah) is blood between the arachnoid membrane and the pia mater cover of the brain. Two main reasons for it: trauma to the head and spontaneous sah due to a ruptured cerebral aneurysm. Severe headache, vomiting, confusional state coma the symptoms. It is a medical emergency. It is diagnosed easily by mri. Early treatment results usually in full recovery.