What is arachnoid mater?

The arachnoid mater is one of the three meninges, the protective membranes that cover the brain and spinal cord. The arachnoid mater is a derivative of the neural crest mesectoderm in the embryo.

What is a Meninge?

meninges, singular meninx, three membranous envelopes—pia mater, arachnoid, and dura mater—that surround the brain and spinal cord. The primary function of the meninges and of the cerebrospinal fluid is to protect the central nervous system.

Why is it called arachnoid mater?

The arachnoid mater, named for its spiderweb-like appearance, is a thin, transparent membrane surrounding the spinal cord like a loosely fitting sac. Continuous with the cerebral arachnoid above, it passes through the foramen magnum and descends caudally to the S2 vertebral level.

Is arachnoid mater avascular?

Introduction: The arachnoid mater is a delicate and avascular layer that lies in direct contact with the dura and is separated from the pia mater by the cerebrospinal fluid-filled subarachnoid space.

What are the Leptomeninges?

Leptomeninges: The two innermost layers of tissue that cover the brain and spinal cord. The two layers are called the arachnoid mater and pia mater.

What is between dura mater and arachnoid?

The subdural space is the space that potentially exists between the meningeal layer of the dura and the arachnoid mater. Similar to the epidural space, the subdural space typically exists only under pathological conditions.

What is CSF function?

CSF assists the brain by providing protection, nourishment, and waste removal. The reduction in weight lessens the force applied to the brain parenchyma and cerebral vessels during mechanical injury. Another function of CSF is to maintain homeostasis of the interstitial fluid of the brain.

What is under arachnoid layer?

The space under the arachnoid, the subarachnoid space, is filled with cerebrospinal fluid and contains blood vessels. The pia mater is the innermost layer of meninges. This thin, delicate membrane is tightly bound to the surface of the brain and spinal cord and cannot be dissected away without damaging the surface.

Where does the arachnoid mater end?

S2 vertebral level 2
Gross Anatomy The spinal arachnoid mater becomes continuous with the cerebral arachnoid mater as it traverses the foramen magnum and terminates at the S2 vertebral level 2. It is in direct contact but does not adhere to the inner aspect of the dura mater, from which it is separated by a thin film of lymph.

Where is the arachnoid mater?

spinal cord
The arachnoid mater, named for its spiderweb-like appearance, is a thin, transparent membrane surrounding the spinal cord like a loosely fitting sac. Continuous with the cerebral arachnoid above, it passes through the foramen magnum and descends caudally to the S2 vertebral level.

What are basal cisterns?

The subarachnoid cisterns, or basal cisterns, are compartments within the subarachnoid space where the pia mater and arachnoid membrane are not in close approximation and cerebrospinal fluid (CSF) forms pools or cisterns (Latin: “box”).