Lecture 5: Dural Sinuses, Meninges, and Vasculature Flashcards

1
Q

What are the three layers of the cranial meninges from superficial to deep?

A

Dura Mater, Arachnoid Mater & Pia Mater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the two layers of dura mater?

A

Periosteal Layer: attached to cranial bones

Meningeal Layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the space called between the two layers of the dura mater?

A

Dural Septa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are emissary veins?

A

Veins that drain the scalp into the dural venous sinuses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the structures that collect pools of blood in the brain and drain the central NS, face and scalp?

Where do they ultimately drain to?

A

Dural Venous Sinuses

Internal Jugular Vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What can infections of the scalp lead to?

A

Meningitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are bridging veins?

A

Veins that drain cerebral cortex into the dural venous sinuses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the subdural space?

A

Potential space between arachnoid and dura mater. In theory, this space should not exist.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What can form a subdural space?

A
  1. Bleeding of Bridging Veins
  2. Lumbar Punctures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is found in the subarachnoid space?

A

CSF & Branches of the Internal Carotid A.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can aneurysms form in the subarachnoid space?

A

Low collagen can cause weaker blood vessels, which can lead to higher potential of aneurysms from the Internal Carotid A. branches in the subarachnoid space.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where is pia mater found?

A

Tightly adheres to brain and follows every contour of the brain surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the cranial dural septa? What is their purpose?

A

Meningeal layer of Dura Mater extends as flat partitions deep into the cranial cavity. The septa provides stabilization and support for the brain. It also separates specific parts of the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the falx cerebri separate?

A

The two hemispheres of the cerebrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the tentorium cerebelli separate?

A

Cerebellum from Cerebrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the falx cerebelli separate?

A

The two hemispheres of the cerebellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the diaphragma sellae?

A

Dura Septa that covers the Pituitary Gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What plane is the falx cerebri and falx cerebelli found in?

A

Sagittal Plane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What plane is the tentorium cerebelli found in?

A

Transverse/Horizontal Plane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the dural venous sinuses that are found in the cranial dural septa?

A
  1. Superior Sagittal Sinus
  2. Inferior Sagittal Sinus
  3. Straight Sinus
  4. Transverse Sinus
  5. Sigmoid Sinus
  6. Cavernous Sinus
  7. Superior Petrosal Sinus
  8. Inferior Petrosal Sinus
  9. Confluence of Sinuses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the main artery that supplies the three layers of the cranial meninges? Where does it branch from?

A

Middle Meningeal Artery

ECA –> Maxillary Artery –> MMA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the two branches of the Middle Meningeal Artery?

How does it enter the cranium

A

Anterior and Posterior Branch

Foramen Spinosum

23
Q

What cranial nerve provides sensory afferent information to the meninges?

A

All branches of Cranial Nerve V (Trigeminal Nerve)

24
Q

What causes an epidural hematoma? What does it look like on an x-ray?

A

Ruptured Middle Meningeal Artery - can be caused if hit at the pterion. Lens shaped hematoma on side of brain

Epidural hematoma is when bleeding occurs between the tough outer membrane covering the brain (dura mater) and the skull

25
Q

What is a pterion?

A

Point where temporal bone, parietal bone, sphenoid bone, and frontal bone meet. Middle Meningeal lies deep to it.

26
Q

What causes a subdural hematoma? What does it look like on an x-ray?

A

Bleeding of bridging veins froms blow to head that jerks brain inside cranium (i.e. hitting windshield in car accident). Crescent shaped hematoma on side of brain

gathers between the inner layer of the dura mater and the arachnoid mater of the meninges surrounding the brain. It usually results from tears in bridging veins that cross the subdural space.

27
Q

What causes a subarachnoid hemmorrhage? What does it look like on an x-ray?

A

Ruptured cerebral arteries or anuerysm leading to extravasation of arterial blood into subarachnoid space. Can also be caused by head trauama or a bad lumbar puncture. Spiderweb shape

Predipositions: pregnancy and people with hypertension.

28
Q

Where can the supra-orbital vein, superior ophthalmic vein, and inferior ophthalmic vein drain into?

A
  1. Facial Vein
  2. Dural Venous Sinuses via the orbit
29
Q

What does the Sigmoid sinus drain into?

A

Jugular Vein

30
Q

What structures are in the cavernous sinus?

A

Pituitary Gland - sits in hypohysial fissure

Internal Carotid Artery

CN III (Oculomotor Nerve)

CN IV (Trochlear Nerve)

CN VI (Abducens Nerve)

CN V1 (Ophthalmic Nerve),

CN V2 (Maxillary Nerve)

31
Q

What type of blood surrounds cavernous sinus?

A

Venous Blood

32
Q

What structures sit inside the cavernous sinus and not the wall

A

Internal Carotid A. & Abducens Nerve (CN VI)

33
Q

What structures sit in the wall of the cavernous sinus (Dura Mater)

A

Occulomotor N

Trochlear N

Opthalmic N (CN V1)

Maxillary N (CN V2)

34
Q

What causes a cavernous sinus thrombosis and what are the symptoms?

A

Infection of face that can spread through Facial V. (ophthalmic vein) and reach cavernous sinus.

Symptoms: Edema & chemosis of the eyes (puffiness and redness)

Cranial nerve VI (abducens N) palsy = Eyes can’t move laterally.

HINT THAT IT’S VEIN NOT ARTERY: Veins are bidirectional in the head and neck

35
Q

Where is cerebrospinal fluid (CSF) found?

A

Subarachnoid Space - space between the Arachnoid Mater and Pia Mater

36
Q

What makes CSF?

A

Choroid plexus in ventricles

37
Q

What is the difference between CSF and blood plasma composition?

A

CSF: Greater sodium, hydrogen and calcium but less potassium

38
Q

What structure drains CSF into dural venous sinuses?

A

Arachnoid Granulations

39
Q

What happens if there is a problem with pressure gradient with dural venous sinuses or an obstruction in CSF to the Dural Venous Sinuses?

A

Hydrocephalus (brain has enlarged ventricles)

40
Q

What is unique about the venous structures in the head and neck

A

They are bi-directional. Don’t have valves pushing them in one direction. Move through pressure gradient.

41
Q

What is the main artery that supplies the neck and face and what are it’s main branches?

A

Common Carotid A.

External Carotid A. & Internal Carotid A.

42
Q

What is the Carotid Sinus & where is it found?

A

reflex area of the carotid artery, consisting of baroreceptors which monitor blood pressure.

Found superior to bifurcation on internal carotid A.

43
Q

What are the branches of the External Carotid A.

A

Superior Thyroid

Ascending Pharyngeal A

Lingual A.

Facial A.

Occipital A.

Posterior Auricular A.

Maxillary A.

Superficial Temporal A.

Some Anatomist Like Freaking Out Poor Medical Students

44
Q

What is the terminal branch of the Facial A.

A

Angular A.

located in the medial angle of the eye

45
Q

What are the divisions of the Maxillary A.

A

Mandibular Part

Pterygoid Part

Pterygopalatine Part

46
Q

List the Maxillary A branches you should know for lab

A

Mandibular Part: Middle Meningeal, Inferior Alveolar,

Pterygoid Part: Buccal, Anterior and Posterior Deep Temporal

Pterygopalatine Part: Posterior Superior Alveolar, Infraorbital, Descending Palatine, Greater Palatine, Lesser Palatine, Sphenopalatine

47
Q

Route of Internal Carotid A

A

Doesn’t branch in neck. Enters cranium via carotid canal in temporal bone. Courses through cavernous sinus then branches.

48
Q

Branches of Internal Carotid A

A

Opthalmic A.

Anterior Cerebral A.

Middle Cerebral A.

49
Q

What are the branches of the Opthalmic A for lab

A

Lacrimal A.

Supraorbital A.

Supratrochlear A.

Anterior Ethmoidal A.

Posterior Ethmoidal A.

Note: opthalmic means relating to eye (LSA - Looking Superior w/ Eyes

50
Q

What is the Circle of Willis

A

The Circle of Willis is the joining area of several arteries at the bottom (inferior) side of the brain

51
Q

What structures make up the circle in the Circle of Willis

Hint: list from top to bottom

A

Anterior cerebral artery (2)

Anterior communicating artery

Internal Carotid A. (2)

Middle cerebral A. (2)

Posterior communicating artery (2)

Posterior cerebral A. (2)

Basilar A.

52
Q

What is Subclavian Steal Syndrome

A

Occlusion of the subclavian artery. Blockage causes reverse flow through the verterbral artery of the affected side to supply blood to upper extremity, decreasing blood flow to the brain.

53
Q

What is the Danger Zone

A

Triangle area from upper lip and bridge of nose where an infection can lead to cavernous thrombosis.