Anatomy HNS 1 - Cranium, Meninges and Brain Flashcards
1
Q
What are the bones of the cranium?
A
- Occipital
- Sphenoid
- Parietal (2)
- Ethmoid
- Temporal (2)
- Frontal
2
Q
What are the bones of the facial skeleton
A
- Maxilla (2)
- Zygoma (2)
- Nasal (2)
- Vomer
- Lacrimal (2)
- Palatine (2)
- Inferior nasal conchae (2)
- Mandible
3
Q
What 3 structures are present in the ethmoid bone
A
- Orbital plate
- Middle nasal conchae
- Perpendicular plate
4
Q
What foramen is present on the mandible
A
Mental foramen
5
Q
What 2 structures are present on the maxilla
A
- Anterior nasal spine
2. Infraorbital foramen
6
Q
The sphenoid bone consists of 2 wings which are
A
Greater wing and lesser wing
7
Q
Which bone contains the sagittal suture
A
Parietal bone
8
Q
Which suture runs horizontally, and what bone is it part of?
A
Coronal suture, runs along frontal bone
9
Q
Which suture runs posteriorly on the occipital bone
A
Lambdoid suture
10
Q
What is the point where the sagittal suture and lambdoid suture meet?
A
Lambda
11
Q
What is the point where the coronal suture and the sagittal suture meet?
A
Bregma
12
Q
The temporal bone is posterior to the frontal bone and the ….
A
Sphenoid bone
13
Q
On what bone is the mastoid process?
A
Temporal
14
Q
On which bone is the styloid process
A
Temporal
15
Q
What is the name of the region where 4 bones meet?
What are the 4 bones that meet
A
The pterion
- Greater wing of sphenoid
- Frontal
- Temporal
- Parietal
16
Q
The pterion is the weakest part of the skull. Trauma to this structure may rupture what to cause an epidural haematoma?
A
Middle meningeal artery
17
Q
From what artery does the middle meningeal artery arise?
A
Maxillary artery - a branch of the external carotid artery
18
Q
How many fossa are there in the cranial base?
A
3
19
Q
What does the anterior cranial fossa contain?
A
Frontal lobes
20
Q
What bone is the cribriform plate part of?
A
Ethmoid
21
Q
What forms the lower/posterior border of the anterior cranial fossa?
A
Lesser wing of sphenoid and body of sphenoid
22
Q
What is the foramina between the frontal crest and cribriform plate?
A
Foramen cecum
23
Q
What does the middle cranial fossa contain?
A
Temporal lobes
24
Q
Which 3 foramina are part of the greater wing of the sphenoid?
A
Foramen lacerum Foramen vale (largest) Foramen spinosa (lateral)
25
Which is the deepest and largest fossa?
Posterior cranial fossa
26
What does the posterior cranial fossa contain?
Brainstem and cerebellum
27
Where is the foramen magnum located?
Posterior cranial fossa
28
Name the 11 structures in the cranial fossa that allow nerves/vasculature to pass through
(anterior to posterior)
1. Cribriform plate
2. Optic canal
3. Superior orbital fissure
4. Foramen rotundum
5. Foramen ovale
6. Foramen spinosum
7. Carotid canal
8. Internal acoustic meatus
9. Jugular foramen
10. Hypoglossal canal
11. Foramen magnum
29
What passes through the cribriform plate?
Olfactory nerve
30
What passes through the optic canal
1. Optic nerve (& central artery of retina)
| 2. Ophthalmic artery
31
What passes through the superior orbital fissure
1. Oculomotor nerve
2. Trochlear
3. Ophthalmic division of trigeminal
4. Abducens
5. Superior ophthalmic vein
32
What passes through the foramen rotundum
Maxillary division of trigeminal nerve
33
What passes through the foramen ovale
Mandibular division of trigeminal nerve
34
What passes through the foramen spinosum
Middle meningeal artery and vein
35
Nothing significant passes through foramen lacerum
Y
36
What passes through carotid canal
Internal carotid artery
37
What passes through internal acoustic meatus
1. Facial nerve
2. Vestibulocochlear nerve
3. Labyrinthine artery
38
What passes through the jugular foramen
1. Glossopharyngeal nerve
2. Vagus nerve
3. Accessory nerve
4. Sigmoid sinus - internal jugular vein
39
What passes through the hypoglossal canal
Hypoglossal nerve
40
What passes through the foramen magnum
1. Vertebral arteries
2. Medulla of brain
3. Spinal roots of accessory nerve
41
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Y
42
Superficial to deep - what are the tissue components of the scalp
```
S - Skin
C - Connective tissue
A - Aponeurosis
L - Loose areolar tissue
P - Periosteum
```
43
What are the 3 meningeal layers of the brain
1. Outer dura mater
2. Middle layer - arachnoid mater
3. Inner layer - Pia mater
44
What are the 2 dura mater layers in the brain
1. Outer periosteal layer
| 2. Inner meningeal layer
45
What do the 2 dura mater layers separate from each other to form?
1. Dural partitions
| 2. Intradural venous sinuses
46
Within what fissure does the falx cerebri dural fold exist?
Longitudinal cerebral fissure - separates left and right hemisphere
47
Where does the tentorium cerebelli dural fold exist?
Between the occipital lobes
| Also between cerebellum and brainstem
48
What are the 3 types of herniation?
1. Subfalcine herniation
2. Uncal herniation
3. Tonsillar herniation
49
What happens in a subfalcine herniation
Frontal lobe herniates below falx cerebra
- Not clinically significant
50
Describe uncal herniation
Uncus of temporal lobe herniates below tentorium cerebelli - compresses midbrain
Can lead to loss of consciousness
51
Describe tonsillar herniation
Cerebellar tonsils move downwards through the foramen magnum - may cause compression of the medulla
This can lead to cardiorespiratory arrest
52
Where is CSF present?
In the ventricles
53
CSF is not ECF. How does ECF drain back into the capillaries?
Via BBB
54
2 functions of CSF
1. Shock impact - protects the brain
| 2. Nutrition for the brain
55
Explain how CSF is formed and drained
1. Choroid plexi create CSF in each ventricle
2. Lateral ventricles drain into 3rd ventricle via inter ventricular foramina
3. 3rd into 4th via cerebral aqueduct
4. From the 4th ventricle into subarachnoid space via foramina of luschka and magendie
5. CSF drains from subarachnoid space into dural venous sinuses via arachnoid villi
56
What is the source of anterior blood supply to the brain
Internal carotids
57
What is the source of posterior blood supply to the brain?
Vertebro-basilar
58
At what vertebral level does the common carotid split into the internal and external carotids?
C4
59
The internal carotid artery enters the cranium through which foramen?
Carotid canal
60
In the cranial cavity, what 3 branches does the internal carotid divide into?
1. Ophthalmic branch
2. Anterior cerebral artery - supplies medial surface and small superior strip on the lateral surface
3. Middle cerebral artery - main branch of ICA - goes through transverse fissure of the brain and supplies most of lateral surface
61
Where do the vertebral arteries come from?
1st part of subclavian arteries
62
Through which foramina of C1-C6 vertebrae does the vertebral artery ascend?
Transverse foramina
63
What are the 3 branches of the vertebral artery
1. Anterior spinal artery - anterior 2/3rds of SC
2. Posterior spinal - posterior 1/3rd of SC
3. Posterior inferior cerebellar artery - supplies posterior inferior aspect of cerebellum
64
What do the vertebral arteries unite to form?
Basilar artery on the anterior aspect of the pons
65
What are the branches of the basilar artery
1. Anterior inferior cerebellar artery
2. Pontine arteries
3. Labyrinthine arteries
4. Superior cerebellar arteries
5. Posterior cerebral arteries
66
Which artery joins the 2 anterior cerebral arteries?
Anterior communicating artery
67
What connects the posterior cerebral artery to the middle cerebral artery?
Posterior communicating artery
68
How is blood from the cerebral veins drained?
Drained into dural venous sinuses - then drained into the internal jugular vein
69
Superior and inferior sagittal sinuses run along the margin of what?
Falx cerebri
70
Transverse sinuses run along what margin?
Tentorium cerebelli
71
Between which 2 structures does the cavernous sinus exist?
Sella turcica and temporal lobe
72
The inferior sagittal sinus drains into what before draining into the confluence of sinuses (before draining into the TV sinus)
Straight sinus
Superior sagittal sinus drains straight into confluence of sinuses
73
What does the confluence of sinuses drain into before draining into the internal jugular vein?
TV sinus - Sigmoid sinus - Internal jugular vein
74
Where does the cavernous sinus sit?
Lateral side of the body of sphenoid bone
75
Where does the cavernous sinus receive blood from?
Cerebral veins
Ophthalmic veins
Emissary veins (outside cranium)
76
Due to the location of the cavernous sinuses, what are they susceptible to?
Inflammation
77
What is the medial border of the cavernous sinus?
1. Internal carotid artery
| 2. Abducens nerve - lies alongside artery so is susceptible to damage
78
What lies on the lateral border of the cavernous sinus
CrN 3, 4, Vi, Vii
