Dural Venous Sinuses

Question 1

What are the layers of the dura mater?

Answer 1

Periosteal layer and meningeal layer

Question 2

When do the periosteal layer and meningeal layer separate?

Answer 2

For dural venous sinuses

Question 3

Whate does the emissary vein drain?

Answer 3

Drains from scalp to dural venous sinus

Question 4

What is the subdural space?

Answer 4

A POTENTIAL space, can be opened due to bleeding from bridging veins or after an LP due to negative pressure

Question 5

Where is CSF found?

Answer 5

Subarachnoid space

Question 6

What is the main artery supply to the brain?

Answer 6

Internal carotid a

Question 7

How are septa made?

Answer 7

When the meningeal layer of the dura mater separates, comes together, and goes down into the brain

Question 8

What are septa for?

Answer 8

Stabilization and support

Question 9

What are the main cranial dural septa?

Answer 9

Falx cerebri, tentorium cerebelli, falx cerebelli, diaphragma sellae

Question 10

What does the falx cerebri separate?

Answer 10

The two hemispheres of the brain (sagittal plane)

Question 11

What does the tentorium cerebelli separate?

Answer 11

The cerebellum from the cerebrum (horizontal plane)

Question 12

Where is the diaphragma sellae?

Answer 12

At the optic chiasm near the pituitary gland

Question 13

What does the falx cerebelli separate?

Answer 13

The two hemispheres of the cerebellum (sagittal plane)

Question 14

What is the main arterial supply to the meninges?

Answer 14

Middle meningeal artery

Question 15

What are the branches of the main arterial supply to the meninges?

Answer 15

Frontal (anterior) and parietal (posterior)

Question 16

Where does the middle meningeal artery arise?

Answer 16

The maxillary artery

Question 17

What does the middle meningeal artery split into?

Answer 17

Frontal (anterior) branch and parietal (posterior) branch

Question 18

What foramen does the middle meningeal artery come out of the skull from?

Answer 18

Foramen spinosum

Question 19

What nerves innervate the meninges?

Answer 19

V1, V2, V3, and C2/C3 fibers

Question 20

What is it called when you rupture the middle meningeal a?

Answer 20

Epidural hematoma (because artery is between skull bone and dura mater)

Question 21

What is the junction of the frontal, parietal, sphenoid, and temporal bones called?

Answer 21

Pterion

Question 22

What is the lucid interval?

Answer 22

Few hours when blood is slowly filling epidural space before brain is herniated somewhere suddenly

Question 23

What is it called when you rupture the bridging vein?

Answer 23

Subdural hemorrhage (in “potential space”). Usually acceleration/deceleration injury

Question 24

What does the bridging vein drain?

Answer 24

From the cortex into the dural venous sinuses

Question 25

What is it called when an aneurysm ruptures? Why is this bad?

Answer 25

Subarachnoid hemorrhage. Subarachnoid space usually houses CSF and is not prepared to handle blood

Question 26

How does imaging typically present with epidural hematoma vs subdural hematoma vs subarachnoid hemorrhage?

Answer 26

Epidural hematoma - “lens”- shaped due to the dura being more tightly adhered to suture lines of the skull
Subdural hematoma - “crescent”-shaped
Subarachnoid hemorrhage - “spiderweb”, blood pools deep in brain

Question 27

What sinus becomes the internal jugular vein?

Answer 27

The sigmoid sinus

Question 28

Which sinuses help drain the cavernous sinus?

Answer 28

Superior petrosal sinus and inferior petrosal sinus

Question 29

Which cranial nerves are in the cavernous sinus?

Answer 29

CN III, IV, V1, V2, VI

Question 30

What gland is located in the cavernous sinus?

Answer 30

Pituitary gland

Question 31

What are the four parts of the internal carotid artery?

Answer 31

Cervical, petrous, cavernous, cerebral (which eventually gives off circle of willis arteries)

Question 32

What are clinical signs of cavernous sinus thrombosis?

Answer 32

Periorbital edema, fever, cranial nerve palsies (ex: lateral gaze defect from CN VI damage)

Question 33

Where is the CSF formed?

Answer 33

The choroid plexus within ventricles of the brain (ependymal cells)

Question 34

How does CSF drain?

Answer 34

From ventricles to subarachnoid space and then through arachnoid granulations to dural venous sinuses to venous system

Question 35

What happens if the arachnoid granulations get clogged or don’t work properly?

Answer 35

Hydrocephalus