l2 SAQ Meninges and Cisterns Quiz

Layers of the Meninges

• Meninges consist of three layers: dura mater, arachnoid mater, and pia mater.
• Layers are organized from superficial to deep: dura mater (outermost), arachnoid mater, and pia mater (innermost).

Function of the Meninges

• Meninges protect the brain and spinal cord.
• Provide a supportive framework for blood vessels and contain cerebrospinal fluid (CSF) which cushions the brain.

Subarachnoid Space

• Located between the arachnoid mater and pia mater.
• Contains cerebrospinal fluid, blood vessels, and is crucial for shock absorption.

Cisterns

• Expanded areas within the subarachnoid space filled with cerebrospinal fluid.
• Act as reservoirs for CSF and provide additional cushioning for the brain.

Folds of the Dura Mater

• Falx cerebri: separates the cerebral hemispheres.
• Tentorium cerebelli: separates the cerebellum from the cerebrum.

Function of the Falx Cerebri

• Supports the brain by anchoring it to the skull and preventing excessive movement.
• Helps maintain the structure of the cerebral hemispheres.

Separation by Tentorium Cerebelli

• Divides the supratentorial region (above the tentorium) from the infratentorial region (below the tentorium).

Supratentorial Region

• Contains cerebral hemispheres and structures such as the thalamus and basal ganglia.

Infratentorial Region

• Houses the cerebellum and brainstem.

Structures in the Subarachnoid Space

• Contains cerebrospinal fluid, major blood vessels, and cranial nerves.

Location of Childhood vs. Adult Tumors

• Childhood tumors are more commonly located in the infratentorial region.
• Adult tumors are typically found in the supratentorial region.

Function of the Falx Cerebelli

• Partially separates the two hemispheres of the cerebellum.

Coverage by Diaphragma Sellae

• Covers the sella turcica, which houses the pituitary gland.

Significance of Dural Folds

• Dural folds support and stabilize the brain, preventing displacement and shear forces during movement.

Petalia

• Refers to asymmetrical protrusions of the cerebral hemispheres that can influence the shape of the skull.

Number of Meningeal Layers

• Meninges consist of three distinct layers.

Venous Sinuses Location

• Venous sinuses lie between the periosteal and meningeal layers of the dura mater.

Function of Venous Sinuses

• Carry deoxygenated blood away from the brain and circulate cerebral spinal fluid.

Meningeal Spaces

• Spaces from superficial to deep:
  • Epidural space (contains fat and blood vessels)
  • Subdural space (potential space, normally empty)
  • Subarachnoid space (contains cerebrospinal fluid).

Test your knowledge of the meninges and cisterns with this quiz by Prof Dara M Cannon. Learn about the layers, functions, and structures that protect the brain and spinal cord.