In a subarachnoid haemorrhage, bleeding occurs primarily into which space?

In a subarachnoid haemorrhage, bleeding occurs primarily into which space?

• A. Bleeding into the subarachnoid space
• B. Bleeding into the epidural space
• C. Bleeding into the subdural space
• D. Bleeding into the dura mater

Answer: (A)

The key idea is that a subarachnoid hemorrhage involves bleeding into the subarachnoid space, the gap between the arachnoid mater and the pia mater that normally contains cerebrospinal fluid. When a vessel such as a berry aneurysm ruptures, blood enters this space and Disseminates around the brain with the CSF. This differs from bleeding into the epidural space (between skull and dura), the subdural space (between dura and arachnoid), or bleeding within the dura itself, which are not characteristic of subarachnoid hemorrhage.

The key idea is that a subarachnoid hemorrhage involves bleeding into the subarachnoid space, the gap between the arachnoid mater and the pia mater that normally contains cerebrospinal fluid. When a vessel such as a berry aneurysm ruptures, blood enters this space and Disseminates around the brain with the CSF. This differs from bleeding into the epidural space (between skull and dura), the subdural space (between dura and arachnoid), or bleeding within the dura itself, which are not characteristic of subarachnoid hemorrhage.