Cranial Contents

Question 1

Cavernous sinuses

Answer 1

On either side of the sella turcica (sphenoid)
Gets blood from ophthalmic veins, superficial middle cerebral vein, sphenopareital sinus
Communicate with eachother via intercavernous sinuses
Drain posteriorly into the superior/inferior petrosal sinuses
Structures that run through sinus: internal carotid artery, oculomotor nerve, trochlear nerve, ophthalmic and maxillary divisions of trigeminal nerve, abducens nerve

Question 2

How does the middle menangial artery enter the skull?

Answer 2

Foramen spinosum

Question 3

What is the primary artery of the dura mater?

Answer 3

Middle menangial artery

Question 4

How does CSF leave the ventricles and enter the blood stream?

Answer 4

Leaves through apertures in the 4th ventricle (near brainstem/cerebellum) into the subarachnoid space
It then enters superior sagittal sinus via arachnoid villi

Question 5

What structures run through the center of the cavernous sinuses?

Answer 5

Internal carotid artery

Abducens (CN VI)

Question 6

Emissary veins

Answer 6

Veins connecting diploic veins to the superior sagittal sinus

Question 7

Epidural hematoma

Answer 7

Aka menangial artery tear
Caused by fracture in skull = tear in menangial artery
Leads to bleeding of arterial blood between dura mater and skull

Question 8

Falx cerebri

Answer 8

Double layer of meningial dura
In the longitudinal fissure separating the cerebral hemispheres
Extends from crista galli (ethmoid) - internal occipital protuberance (occipital)
Reduces side to side movement of the brain

Question 9

What are the pathways for venous drainage from the scalp?

Answer 9

Can directly drain into internal/external jugular veins
OR
Drain into diploic veins - emissary veins - superior sagittal sinus

Question 10

Tentorial notch

Answer 10

Hold in tentorium cerebelli through which the brainstem travels

Question 11

Subdural hematoma

Answer 11

Aka cerebral vein tear

Venous blood collects between dura and arachnoid mater

Question 12

Which part of the brain sites in the middle cranial fossa?

Answer 12

Temporal lobes

Question 13

Superior petrosal sinuses

Answer 13

Drain blood from cavernous sinuses - transverse sinuses (as they become the sigmoid sinuses)
At crest of petrous part of temporal bone

Question 14

Tentorum cerebelli

Answer 14

Separates occipital lobes of cerebrum from the cerebellum
Attached to pterous portion of temporal bone - anterior clinoid processes (sphenoid)
Tentorial notch: hole through which brainstem travels
Supports posterior cerebrum so it doesn’t compress cerebellum

Question 15

Which artery can be torn when there is a fracture at the pterion?

Answer 15

Middle menangial artery

Question 16

Sigmoid sinuses

Answer 16

S shaped
Run in posterior cranial fossae (grooves)
Gets blood from transverse sinuses to jugular foramen - internal jugular vein

Question 17

Which layer of the dura mater is considered to be the “true dura”?

Answer 17

Meningeal dura mater

Question 18

Circle of Willis

Answer 18

Circular anastomotic communication of the arteries at the base of the brain
Contributing arteries:
- Basilar
- posterior cerebral
- posterior communicating
- internal carotid
- middle cerebral
- anterior cerebral
- anterior communicating

Question 19

What is the significance of blood from the scalp being able to drain into diploic veins?

Answer 19

Infections on the scalp can enter brain through venous drainage pattern
Scalp - diploic veins - emissary veins - superior sagittal sinus

Question 20

Sphenopareital sinus

Answer 20

In edge of lesser wing of sphenoid

Drains into cavernous sinuses

Question 21

Straight sinus

Answer 21

Between falx cerebri and tentorium cerebelli
Receives blood from inferior sagittal sinus, great cerebral vein
Drains into confluence of sinuses

Question 22

Which nerves relay sensory information from the meninges?

Answer 22

All divisions of the trigeminal nerve (CN V)

C2, C3

Question 23

Meningeal layer that forms septae

Answer 23

Meningeal dura mater

Question 24

Inferior sagittal sinus

Answer 24

Along inferior edge of falx cerebri

Joins with great cerebral vein (of Galen) to empty into straight sinus

Question 25

Where is CSF in the brain?

Answer 25

Subarachnoid space

Question 26

Confluence of sinuses

Answer 26

Receives blood from superior sagittal sinus, straight sinus | Drains into transverse sinuses on either side

Question 27

Which part of the brain sits in the posterior cranial fossa?

Answer 27

Crerebellum

Question 28

What structures run through the lateral walls of the cavernous sinuses? (From superior to inferior)

Answer 28

Oculomotor (CN III) Trochlear (IV) Opthalmic divison of trigeminal (V1) Maxillary division of trigeminal (V2)

Question 29

Meningeal layer attached to internal periosteum (endocranium)

Answer 29

Periosteal dura mater

Question 30

Which part of the brain sits in the anterior cranial fossa?

Answer 30

Frontal lobes

Question 31

Great cerebral vein (of Galen)

Answer 31

True vein - drains blood from deep brain - straight sinus

Question 32

Superior sagittal sinus

Answer 32

Runs longitudinally along midline of skull Receives blood from cerebral veins Flows anterior-posterior - confluence of sinuses Also receives CSF from subarachnoid space via arachnoid villi

Question 33

Diploic veins

Answer 33

Veins within the flat bones of the skull | Drain into superior sagittal sinus via emissary veins

Question 34

Symptoms of tumors of the pituitary gland

Answer 34

Can cause diaphragma sellae to bulge superiorly and press on optic chiasma, causing visual symptoms as well as endocrine symptoms

Question 35

What forms the blood-brain barrier

Answer 35

Brain capillaries - continuous basement membrane, tight junctions Astrocytes - perivascular feet

Question 36

Subarachnoid hemorrhage

Answer 36

Aka cerebral artery rupture Arterial blood collects in subarachnoid space Aneurysm, CVA

Question 37

Inferior petrosal sinuses

Answer 37

Drain blood from cavernous sinuses to jugular foramen | Run posteriorly and laterally in groove between petrous portion of temporal bone and basiliar portion of occipital bone

Question 38

Where is CSF made?

Answer 38

Ventricles of the brain | Product of blood plasma - continuously made

Question 39

Falx cerebelli

Answer 39

Partially separates the cerebellar hemispheres

Question 40

Diaphragma sellae

Answer 40

Horizontal sheet of dura over pituitary gland in sella turcica (sphenoid) Encircles stalk of pituitary

Question 41

Attachment of dura mater to bones of the floor of the cranium is ______ than it’s attachment to the calvaria

Answer 41

Stronger

Question 42

Superficial middle cerebral vein

Answer 42

In lateral fissure of the cerebral hemispheres | Drains into sphenoparietal sinus (then cavernous sinuses)

Question 43

How can headaches be caused by the meninges?

Answer 43

Deformation of the dura mater from distention of the menangial arteries Changes in pressure of subarachnoid space (lumbar puncture)

Question 44

Arachnoid villi

Answer 44

Projections of the arachnoid mater into the superior sagittal space CSF travels into bloodstream through these

Question 45

Transverse sinuses

Answer 45

Carries blood laterally from the confluence of sinuses - sigmoid sinuses