What are the three layers of the meninges?

The brain is protected by three membranes: the dura mater (tough outer layer), the arachnoid mater (web-like middle layer), and the pia mater (delicate inner layer).

What are the two layers of the cranial dura mater?

The cranial dura mater consists of an endosteal layer (inner periosteum of the skull) and a meningeal layer (true dura mater). They are fused except where dural venous sinuses are located.

What are the main dural folds and what do they do?

The meningeal layer forms folds to compartmentalize the brain: Falx cerebri separates cerebral hemispheres, Tentorium cerebelli separates cerebrum from cerebellum, Falx cerebelli separates cerebellar hemispheres, and Diaphragma sellae forms roof of the hypophyseal fossa.

What is the trigeminal (Meckel's) cave?

It's a dural recess that encloses the trigeminal ganglion, located over the trigeminal impression on the petrous temporal bone.

How is the dura mater supplied with blood?

Blood supply varies by cranial fossa: Anterior fossa receives from ophthalmic, ethmoidal, and middle meningeal arteries; middle fossa from middle meningeal, accessory meningeal, and internal carotid branches; posterior fossa from vertebral and occipital artery branches.

Which nerves innervate the dura mater?

Innervation is divided: Supratentorial dura is mainly by the ophthalmic nerve (CN V1), while infratentorial dura receives from various nerves including maxillary (CN V2), mandibular (CN V3), vagus, hypoglossal, and spinal nerves.

Cranial Cavity & Meninges – Dura, Arachnoid, Pia