Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HAE Quiz 3 > The Skull, CN, Arteries, Veins > Flashcards

The Skull, CN, Arteries, Veins Flashcards

1
Q

Objectives
• Discuss the basic topography of the brain.
• Describe the osseous structure of the skull base and the way by which major structures enter or exit the skull.
• Explain the origin of cranial nerves from the CNS and their exit from the skull.
• Describe the meningeal coverings of the brain and the functional importance of these coverings.
• Name the two primary arteries that supply the brain; describe their course and major branches.
• Discuss the venous drainage of the brain including the dural sinuses. Consider the implications of obstruction at various points.
• Explain the production and circulation of cerebrospinal fluid

A

Objectives
• Discuss the basic topography of the brain.
• Describe the osseous structure of the skull base and the way by which major structures enter or exit the skull.
• Explain the origin of cranial nerves from the CNS and their exit from the skull.
• Describe the meningeal coverings of the brain and the functional importance of these coverings.
• Name the two primary arteries that supply the brain; describe their course and major branches.
• Discuss the venous drainage of the brain including the dural sinuses. Consider the implications of obstruction at various points.
• Explain the production and circulation of cerebrospinal fluid

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

Inside of skull NP-8, T483
• The inside of the skull is specifically designed to fit the brain and to allow passage of cranial nerves and blood vessels.
• The anterior cranial fossa fits the frontal lobes
• The base of the middle cranial fossa fits the temporal lobes
• The base of the posterior cranial fossa contains the cerebellum and brain stem.

A

Inside of skull NP-8, T483
• The inside of the skull is specifically designed to fit the brain and to allow passage of cranial nerves and blood vessels.
• The anterior cranial fossa fits the frontal lobes
• The base of the middle cranial fossa fits the temporal lobes
• The base of the posterior cranial fossa contains the cerebellum and brain stem.

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

• What landmarks on the brain divide the frontal, parietal, temporal, and occipital lobes?

A
  • The frontal lobe is rostral to the central sulcus
  • The parietal lobe is posterior to the central sulcus
  • The temporal lobe is ventral to the frontal and parietal lobes and separated from them, for the most part, by the lateral fissure
  • There is no clear line of separation between the parietal lobe and occipital lobe on the lateral hemisphere (on the medial side there is a parieto-occipital sulcus).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

• What is the course of Cranial nerve I?

A

Olfactory filaments: enter the anterior cranial fossa via cribriform plate and connect to the olfactory bulb of the brain. T484

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

• What is the course of Cranial nerve II?

A

Optic “nerve”: enters skull though optic canal and connects to the thalamus. T484

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

• What is the course of Cranial nerve III?

A

Oculomotor nerve: arises from the midbrain and passes through the superior orbital fissure after coursing within the lateral wall of the cavernous sinus. T484

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

• What is the course of Cranial nerve IV?

A

Trochlear nerve: arises from the dorsal midbrain and passes through the superior orbital fissure after coursing within the lateral wall of the cavernous sinus. T484

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

• What is the course of Cranial nerve V?

A

Trigeminal nerve: enters the brain at the pons. The trigeminal ganglion is in the lateral wall of the cavernous sinus. The three divisions of the trigeminal nerve enter the middle cranial fossa through different foramina.
 V1 - superior orbital fissure
 V2 - foramen rotundum
 V3 - foramen ovale T484

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

• What is the course of Cranial nerve VI?

A

Abducens nerve: is a nerve of the pons that leaves the brain at the medullary-pontine junction. It enters the dura and passes through the cavernous sinus before leaving the skull through the superior orbital fissure. T484

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

• What is the course of Cranial nerve VII?

A

Facial nerve: is a nerve of the pons that leaves the brain at the medullary-pontine junction. It leaves cranial cavity through internal acoustic meatus. However, it follows a very long course in the petrous temporal bone (facial canal), with the main part leaving the skull via the stylomastoid foramen. T484

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

• What is the course of Cranial nerve VIII?

A

Vestibulocochlear nerve: is a nerve of the pons that leaves the brain at the medullary-pontine junction. It exits the posterior cranial fossa through internal acoustic meatus. T484

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

• What is the course of Cranial nerve IX?

A

Glossopharyngeal nerve: is a nerve of the medulla that leaves the lateral side of the brain stem as many small filaments. It exits the skull through the jugular foramen. T484

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

• What is the course of Cranial nerve X?

A

Vagus nerve: is a nerve of the medulla that leaves the side of the brain stem as many small filaments just caudal to CNIX. It leaves the posterior cranial fossa through the jugular foramen. T484

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

• What is the course of Cranial nerve XI?

A

(Spinal) Accessory nerve: actually arises from neurons in the cervical spinal cord. It leaves the lateral aspect of the cord as filaments and ascends through the foramen magnum before leaving the posterior cranial fossa through the jugular foramen. T484

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

• What is the course of Cranial nerve XII?

A

– Hypoglossal nerve: is a nerve that leaves the ventral medulla via many filaments. It exits the posterior cranial fossa via the hypoglossal canal. T484

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

• What anchors the dura mater to the skull?

A

• The inside of the skull is lined with dura mater that is anchored to the skull by Sharpey’s fibers (in a similar manner to periosteum) (no image).

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

What are dural reflections?

A
  • There are basically two layers of dura, with the outer one functioning like periosteum and the inner layer (the one not intimately adhered to the skull) folding into the inside of the cranial cavity in several “dural reflections”. T526 (dural layers), T524 (dural reflections)
  • These form shelves that compartmentalize the inside of the skull, separating parts of the brain and stabilizing them.
  • The shelves are incomplete, allowing parts of the brain to communicate with one another.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

• What are the four important dural reflections?

A 
	falx cerebri
	falx cerebelli
	tentorium cerebelli
	diaphragma sellae
	T524 (dural reflections)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the tentorial notch?

A

 an opening exists in the posterior fossa (the tentorial notch) to permit the brain stem to connect with the upper part of the brain (the forebrain).

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

Where are the dural venous sinuses located?

A
  • where the reflections attach to the skull and where the dural reflections meet.
  • These are venous structures, lined by endothelium, whose walls are comprised of dura. More on them in Venous Sinuses
21
Q

• What is the main artery supplying the dura? What is its course? What is its clinical significance?

A

 middle meningeal artery NP-55, which
 runs between the outer (periosteal) layer of the dura and the skull bone.
 Could be injured by a skull fracture, resulting in an EPIdural hematoma T525-top

22
Q

• What is the arachnoid mater? What is the subdural space? What is the subdural space filled with?

A

a very thin and filmy but watertight layer that is applied to the inside of the dura, but not attached to it.
• There is a potential space (the subdural space) that can be easily developed by any abnormal fluid collection T525-top.

23
Q

• What is the pia mater? What is the subarachnoid space and what is it filled with?

A
  • a thin layer that is directly applied to the brain (and cannot be removed). It is separated from the arachnoid by the subarachnoid space that is filled with cerebrospinal fluid CSF.
  • This fluid and the surrounding membranes get infected in meningitis.
24
Q

At what Leptomeninges level do the major arteries and cerebral veins travel through the skull?

A

• The major arteries and the cerebral veins travel in the subarachnoid space surrounded by CSF.

25
Q

What are the Venous Sinuses? What are they lined with? T526-LUQ, NP-56

A
  • The principal venous structures in the head are the venous sinuses.
  • lined by endothelium and surrounded by dura (the layers of dura separate to make venous dural sinuses).
26
Q

What are the major venous drains from the brain itself?

A

• There are several types of veins that drain into the venous sinuses. These include cerebral veins that are the major drainage of the brain.

27
Q

What are “bridging veins”?

A

 Cerebral veins penetrate the arachnoid and the dura to enter the sinuses (called “bridging veins” because they have to “bridge” across the subarachnoid space and penetrate the arachnoid and dura to reach the sinus).

28
Q

What is the course of the superior sagittal sinus?

A

• The largest of the sinuses is the superior sagittal sinus, located where the falx cerebri meets the skull. T526

29
Q

What is the course of the inferior sagittal sinus?

A

• the inferior sagittal sinus (at the free edge of the falx cerebri), which joins with the great cerebral vein to make the straight sinus (T526-RLQ).

30
Q

What is the course of the straight sinus?

A

• The straight sinus runs in the tentorium and meets the superior sagittal sinus at the confluence of sinuses, which is directly inside the external occipital protuberance (T526-bottom).

31
Q

What is the course of the transverse sinus?

A

• The transverse sinuses run laterally from the confluence of sinuses and become the sigmoid sinuses, which, in turn, become the internal jugular veins.

32
Q

There are several sinuses at the base of the skull T526, NP-58.

A

There are several sinuses at the base of the skull T526, NP-58.

33
Q

What is the course of the cavernous sinuses? What is its clinical significance? What does the cavernous sinus communicate with?

A

• The cavernous sinuses are the most important of these.
 They are lateral to the pituitary gland and drain blood from the orbit via the ophthalmic veins
 This is a potential route of infection from the face and orbit into the area around the brain. Its symptoms can include pushing the eyeball forward (proptosis) by the dilated ophthalmic veins (small group case)
 The cavernous sinus communicates with the pharyngeal plexus of veins.
T526, NP-58.

34
Q

What are the structures that pass through the Cavernous Sinus?
What are the structures in the wall of the Cavernous Sinus?

A

 T527-RLQ: There are several important structures that pass
 through this sinus
o internal carotid artery
o abducens nerve (CN 6)

 or in the wall of the sinus (CN 3-5)
o trigeminal nerve
o oculomotor nerve
o trochlear nerve

35
Q

What is the course of the superior and inferior petrosal sinuses?

A

 T526-RLQ: The superior and inferior petrosal sinuses drain blood from the cavernous sinus into the beginning and end of the sigmoid sinus, respectively.

36
Q

Arteries T516, T636,

What are the two main pairs of arteries that supply the brain?

A

• There are 2 pairs of main arteries to the brain: the internal carotid arteries and the vertebral arteries (most medial branch of subclavian a – see p. 14

37
Q

• What is the course of the internal carotid arteries?

A
  • traverse the carotid canal, cavernous sinus and then into the subarachnoid space.
  • They give rise to their first intracranial branch, the ophthalmic arteries.
  • They end by dividing into the anterior cerebral arteries and middle cerebral arteries.
  • The anterior cerebral arteries are connected to each other by the anterior communicating artery.
38
Q

What is the course of the vertebral arteries ? T516, T636, – see p. 14

A

• pass up the cervical transverse foramina
• penetrate the posterior atlanto-occipital membrane (see p. 14), then
• meet to make the basilar artery.
 The basilar artery divides to make the posterior cerebral arteries. The posterior communicating arteries connect the posterior cerebrals to the internal carotid.

  • Usually one vertebral artery is larger (dominant).
  • There are branches to the brain stem and spinal cord.
39
Q

• What is the circle of Willis? Whachu talkin’ ‘bout Willis?

A

• The “circle of Willis” is a variable anastomotic pathway to bypass any major artery occlusion. It may prevent stroke in some fortunate patients after major artery occlusions.

40
Q

What are the four types of intracranial hemorrhage?

A
  • Intraparenchymal
  • Subarachnoid
  • Epidural
  • Subdural
41
Q

What are the four ventricles? T632 (Excellent), NP-60

A

• The four ventricles are chambers inside the brain (two lateral ventricles, a 3rd and a 4th) that contain CSF and choroid plexus

42
Q

What is the choroid plexus? T632 (Excellent), NP-60

A

• The choroid plexus is specialized epithelium encasing fenestrated capillaries and is actively involved in manufacture of CSF.

43
Q

The ventricles are connected by channels (openings) that allow CSF to flow between them. How do the lateral ventricles communicate with the third ventricle?

A

• the lateral ventricles communicate with the third ventricle via the interventricular foramen (Monroe – T633-RLQ).

44
Q

• How does the 3rd ventricles communicate with the 4th ventricle?

A

• CSF in the 3rd ventricle traverses the cerebral aqueduct in order to reach the 4th . (T633-RLQ; T632)

45
Q

How does CSF from the 4th ventricle travel to the subarachnoid space?

A

• CSF escapes from the 4th ventricle into the subarachnoid space through the foramina of Luschka and Magendie (T632-bot).

46
Q

All together, describe the communications between the ventricles and the subarachnoid space.

A
  • the lateral ventricles communicate with the third ventricle via the interventricular foramen (Monroe – T633-RLQ).
  • CSF in the 3rd ventricle traverses the cerebral aqueduct in order to reach the 4th . (T633-RLQ; T632)
  • CSF escapes from the 4th ventricle into the subarachnoid space through the foramina of Luschka and Magendie (T632-bot).
47
Q

Describe the locations of the lateral, 3rd, and 4th ventricles.

A

• The lateral ventricles are deep inside each hemisphere of the brain, while the 3rd ventricle is in the midline and the 4th ventricle is between the cerebellum and brain stem. The 4th ventricle connects with the central canal of the spinal cord and with the subarachnoid space (through two foramina).

48
Q

What are arachnoid granulations?

A

• Spinal fluid percolates around the outside of the brain to reach the arachnoid granulations. These are locations where the arachnoid indents through the dura into the venous sinuses (especially the superior sagittal) and allows CSF to flow into the venous system.

HAE Quiz 3 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions