Meninges Flashcards
The brain is protected by 3 layers of membranes called what?
Meninges
Made of 2 layers, this meningeal layer is the most superficial, thick and durable
Dura mater
This meningeal layer is the middle layer of thin membrane that does not follow the contours of the brain
Arachnoid mater
This meningeal layer is a thin, transparent membrane that follows contours of the brain
Pia mater
Layers of the dura mater
- Endosteal
- Meningeal
Dural layer that adheres to the inside of the skull
Endosteal
Dural layer that lays on the 2nd meningeal layer
Meningeal
What is the endosteal layer of the dura mater continuous with?
Periosteum
What part of the CNS is covered by the meningeal layer of the dura mater?
Spinal cord
When separated from the endosteal layer, the meningeal layer forms partitions
Dural infolding
Dural infolding between cerebral hemispheres
Falx cerebri
Dural infolding between cerebellar hemispheres
Falx cerebelli
Dural infolding between the cerebrum and the cerebellum
Tentorium cerebelli
Dural infolding over the hypophyseal fossa
Diaphragm sella
Falx cerebri attachment points
- Crista gali
- Internal occipital protuberance
What does the falx cerebri descend into?
Longitudinal fissure
What is the falx cerebri associated with superiorly?
Superior sagittal sinus
What is the falx cerebri associated with inferiorly?
Inferior sagittal sinus
Falx cerebelli attachment points
- Internal occipital protuberance
- Margin of foramen magnum
What is the falx cerebelli associated with superiorly?
Confluence of the sinus
What is the falx cerebelli associated with inferiorly?
Occipital sinus
Tentorium cerebelli attachment points
- Petrous part of the temporal bone
- Transverse ridge of the occipital bone
What is the tentorium cerebelli associated with medially?
Straight sinus
What is the tentorium cerebelli associated with anteriolaterally?
Superior petrosal sinus
What is the tentorium cerebelli associated with posteriolaterally?
Transverse sinuses
Diaphragm sella attachment points
Clinoid processes
What does the diaphragm sella cover?
- Hypophsealfossa
- Cavernous sinus
Thin membrane adhered to the dura
Arachnoid mater
Part of the arachnoid mater that extends down and attaches to the pia mater
Arachnoid trabecula
Arachnoid mater creates a subarachnoid space for what reason?
For CSF to flow
Outgrowths that extend through dura into sinuses to filter CSF
Arachnoid granulations
Where are arachnoid granulations mainly found?
Superior sagittal sinus
Thin vascular membrane that covers the entire surface of the brain
Pia mater
Channels that form between two dural layers
Dural venous sinuses
What do dural venous sinuses do?
Drains most venous blood and CSF from the brain
Unpaired dural venous sinuses
- Superior sagittal sinus
- Inferior sagittal sinus
- Straight sinus
- Confluence
- Occipital
Paired dural venous sinuses
- Cavernous
- Transverse
- Superior petrosal
- Inferior petrosal
- Sigmoid
Where are the superficial cerebral veins?
On the surface of the cerebrum
Where do the superficial cerebral veins mainly drain into?
Superior sagittal sinus
Where do the deep cerebral veins primarily drain structures into?
Great vein of Galen ——> Straight sinus
These veins pass through the calvaria into the sinuses and can drain skin and scalp into cranial cavity
Emmissary veins
These veins drain the calvaria
Diploic veins
Via which vein are facial veins connected to the cavernous sinuses?
Ophthalamic vein
Arteries supplying CNS
- Internal carotid
- Vertebral arteries
What does the internal carotid supply?
Most of the cerebrum
What do the vertebral arteries supply?
- Brainstem
- Cerebellum
- Posterior cortex
Most pathologies resulting from brain vascular problems relate to two principles
- Chemical
- Physical
If neurons are deprived of O2 or glucose, they will die
Chemical arteriovenous pathology
Enclosed in the skull, the brain can’t accommodate an increase in pressure well thus nervous tissue when compressed will die
Physical arteriovenous pathologies
Bleeding into one of the spaces or potential spaces in the meninges
Intercranial hemorrhage
