Meninges and Venous Sinuses Flashcards
What are 3 layers of the meninges?
- Dura
- Arachnoid
- Pia
How does the cranial dura differ from the spinal dura?
Cranial dura is double layered
What are the 2 layers of cranial dura?
- Periosteal
2. Meningeal
What vein is found at the top of the longitudinal fissure?
Superior sagittal sinus
How many folds of dura are there in the cranial cavity?
4
What are the 2 vertical dural folds found in the cranial cavity?
- Falx cerebri
2. Falx cerebelli
What are the 2 horizontal dural folds found in the cranial cavity?
- Tentorium cerebelli
2. Diaphragma sellae
What is the primary function of the dural partitions?
Restrict rotatory displacement of the brain
Where is the falx cerebri found?
Between cerebral hemispheres
What are the 2 anterior attachments of the falx cerebri?
- Frontal crest
2. Superior sagittal sulcus
What are the 2 posterior attachments of the falx cerebri?
- Internal occipital protuberance
2. Tentorium cerebelli
Where is the superior sagittal sinus found?
Upper margin of the falx cerebri
Describe the 5 stages of blood flow from the superior sagittal sinus until it leaves the skull
- Superior sagittal sinus
- Confluence of sinuses
- Right transverse sinus
- Right sigmoid sinus
- Right internal jugular vein (leaves via jugular foramen)
Where is the inferior sagittal sinus found?
Lower margin of the falx cerebri
Describe the 5 stages of blood flow from the inferior sagittal sinus until it leaves the skull
- Superior sagittal sinus
- Straight sinus
- Confluence of sinuses
- Left transverse sinus
- Left sigmoid sinus
- Left internal jugular vein (leaves via jugular foramen)
Where is the tentorium cerebelli found?
Between the cerebellum and cerebrum
What are the 4 posterior attachments of the tentorium cerebelli?
- Internal occipital protuberance
- Margins of transverse sulcus
- Margins of superior petrosal sulcus
- Posterior clinoid process
What is the anterior attachment of tentorium cerebelli?
Anterior clinoid process on both sides
What gland does the diaphragma sellae cover?
Pituitary gland
Name the 4 attachments of the diaphragma sellae
- Two anterior clinoid processes
2. Two posterior clinoid processes
What shape is the falx cerebelli?
Crescent shaped
What shape is the falx cerebri?
Sickle shaped
Where is the sphenoparietal sinus found?
Lesser wing of sphenoid bone
Where is the cavernous sinus found?
It lies on either side of the sella turcica
What 4 things drain into the cavernous sinus?
- Superior ophthalmic vein
- Inferior ophthalmic vein
- Cerebral veins
- Sphenoparietal sinus
Where does the cavernous sinus empty?
Superior and inferior petrosal sinuses
What are arachnoid granulations?
Small extensions which protrude into superior sagittal sinus
What is the function of arachnoid granulations?
Allow CSF to leak through and enter superior sagittal sinus
Where does the inferior sagittal sinus begin?
Anteriorly in the region of crista galli
What are 4 signs of a patient having a cavernous sinus thrombosis?
- Fever
- Ptosis
- Proptosis
- Ophthalmoplegia
Where does the transverse sinus pass?
Attached base of tentorium cerebelli
Where does the transverse sinus become the sigmoid sinus?
Base of the petrous ridge
Where does the superior petrosal sinus empty?
Sigmoid sinus
Where does the inferior petrosal sinus empty?
Directly into the internal jugular vein
Where is the basilar sinus found?
Below the dura of the clivus
From what 2 sinuses does the basilar sinus receive blood?
- Cavernous sinus
2. Inferior petrosal sinus
Where does the basilar sinus empty?
Vertebral plexus of veins through foramen magnum
