The space between the dura mater and arachnoid is called what?

The space between the dura mater and arachnoid is called what?

• A. Subarachnoid Space
• B. Subdural Space
• C. Dura Mater
• D. Arachnoid

Answer: (B)

Understanding the meninges helps: the dura mater is the tough outer layer, and the arachnoid is the middle, delicate layer. The space between them is the subdural space. It’s a potential space—that is, in a healthy state the layers are in contact and there isn’t a real cavity there. When trauma or disease causes the dura and arachnoid to separate, this space can fill with fluid or blood, forming a subdural hematoma. This is different from the subarachnoid space, which lies between the arachnoid and the pia mater and contains cerebrospinal fluid and blood vessels. The other terms refer to tissue layers rather than spaces.

Understanding the meninges helps: the dura mater is the tough outer layer, and the arachnoid is the middle, delicate layer. The space between them is the subdural space. It’s a potential space—that is, in a healthy state the layers are in contact and there isn’t a real cavity there. When trauma or disease causes the dura and arachnoid to separate, this space can fill with fluid or blood, forming a subdural hematoma. This is different from the subarachnoid space, which lies between the arachnoid and the pia mater and contains cerebrospinal fluid and blood vessels. The other terms refer to tissue layers rather than spaces.