Dural Sinuses And Meninges

Question 1

Which layer of the meninges is the strongest?

Answer 1

Dura mater

Question 2

What are the two layers of the dura mater?

Answer 2

Periosteal and meningeal layer

Question 3

What is the periosteal layer of the dura mater?

Answer 3

More superficial layer

Attaches to the periosteum of the cranial bones

Question 4

Describe the meningeal layer of the dura mater

Answer 4

Lies deep to the periosteal layer
Usually fused to the periosteal layer except in specific areas where the two layers separate to form large, blood-filled spaces called dural venous sinuses

Question 5

Which mater lies immediately internal to the dura mater?

Answer 5

Arachnoid mater

Question 6

What are arachnoid trabeculae?

Answer 6

Delicate web of collagen and elastic fibers that partially compose the arachnoid mater

Question 7

Where is the subdural space?

Answer 7

Between the arachnoid and the overlying dura mater

Question 8

Where is the subarachnoid space?

Answer 8

Immediately deep to the arachnoid

Question 9

Which mater is the innermost of the cranial meninges?

Answer 9

Pia mater which is a thin layer of CT that tightly adheres to the brain and follows every contour of the brain surface

Question 10

What is dural septa?

Answer 10

Extensions of the dura mater that are flat partitions (septa) going deep into the cranial cavity at 4 locations

Question 11

What are the four membranous partitions that separate specific parts of the brain and provide additional stabilization and support to the entire brain?

Answer 11

Falx cerebri, tentorium cerebelli, falx cerebelli and diaphragm sellae

Question 12

What is located within the cranial dural septa?

Answer 12

Dural venous sinuses such as the superior and inferior sagittal sinuses, the straight sinus, sigmoid sinus and transverse sinus

Question 13

Which structures are located within the cavernous sinus?

Answer 13

Internal carotid artery, pituitary gland, CN V1-3, CN IV (Trochlear), III (oculomotor) and VI (abducens)

Question 14

Which structure within the cavernous sinus is the only one that sits freely within it and is not within the wall?

Answer 14

Abducens nerve (CN VI)

Question 15

Which part of the internal carotid artery is within the cavernous sinus?

Answer 15

Cavernous part

Question 16

What is a cavernous sinus thrombosis?

Answer 16

A blood clot within the cavernous sinus usually caused by an infection that spreads from the paranasal sinuses

Question 17

What are the clinical signs of a cavernous sinus thrombosis?

Answer 17

High fever, periorbital edema and chemosis (conjunctival edema), CN palsies (most commonly CN VI with lateral gaze), decreased visual acuity

Question 18

How is a cavernous sinus thrombosis diagnosed?

Answer 18

CT or MRI scans

Question 19

What is the treatment for a cavernous sinus thrombosis?

Answer 19

IV abx, heparin (blood thinner), surgery

Question 20

What causes the spread of infection leading to a cavernous sinus thrombosis?

Answer 20

Due to the anastomosis between the facial vein and superior opthalamic veins

Question 21

What do all dural venous sinuses drain into?

Answer 21

Internal jugular vein

Question 22

The straight, superior and inferior sagittal sinuses are all found in the falx cerebri and converge at the what?

Answer 22

Confluence of sinuses

Question 23

The straight sinus is a continuation of what?

Answer 23

The great cerebal vein and inferior sagittal sinus

Question 24

From the confluence of sinuses, the transverse sinus continues bilaterally and curves into what?

Answer 24

The sigmoid sinus to meet the opening of the internal jugular vein

Question 25

What does the cavernous sinus drain?

Answer 25

The opthalamic veins and from blood returns to the IJV via the superior or inferior petrosal sinuses