What are the meningeal layers of CNS?

The three layers of the meninges are:

1. Dura mater - The outermost and toughest layer is called the dura mater, which is composed of dense collagen fibers and blood vessels. It helps provide structural support and protection for the brain and spinal cord.


2. Arachnoid Mater - The middle layer is called the arachnoid mater, which appears delicate and web-like due to its thin structure. It is separated from the dura mater by the subdural space. The subdural space contains a thin layer of fluid and is potential space, meaning that it can expand in conditions like subdural hematomas.


3. Pia Mater - The innermost layer is called the pia mater, which is closely associated with the surface of the brain and spinal cord. It contains a rich network of blood vessels that supply oxygen and nutrients to the neural tissues.

Below the pia mater, there is the subarachnoid space, which is filled with cerebrospinal fluid (CSF). CSF provides a buoyant environment for the brain, helps in waste removal, and acts as a protective cushion against mechanical trauma.