Anatomy wk 1 Flashcards
1
Q
Name the parts of the brainstem
A
Midbrain
Pons
Medulla
2
Q
What cranial fossa does the brainstem lie in
A
Posterior
3
Q
Which part of the diencephalon is immediately superior to the midbrain
A
Thalamus
4
Q
Which 2 embryological vesicles give rise to the brainstem
A
Midbrain (mesencephalon) and hindbrain (rhombencephalon) vesicles
5
Q
What part of the ventricular system lies within the brainstem
A
Cerebral aqueduct - in midbrain
6
Q
What groove separates the pons from the medulla
A
Pontomedullary junction
7
Q
Which 3 cranial nerves emerge from the pontomedullary junction
A
CN VI, VII, VIII
8
Q
Which cranial nerve has the longest intracranial course + what other Nerve emerging from pontomedullary junction has a long course
A
CN IV
CN VI
9
Q
Consequence of CN VI being damaged
A
CN VI palsy –> unable to abduct eye –> diplopia
10
Q
3 surface features of the medulla
A
Pyramids
Olives
Decussation of the pyramids (Can’t actually see this)
11
Q
What are the pyramids of the medulla made up of
A
Descending motor fibres (corticobulbar fibres and corticospinal fibres) collectively forming the pyramidal tracts
12
Q
What 2 tracts collectively form the pyramidal tract
A
Corticobulbar and corticospinal
13
Q
What occurs at the decussation of the pyramids
A
Motor fibres in CST cross over to contralateral side
14
Q
What are the olives of the medulla made up of
A
Inferior olivary nuclei
15
Q
Function of inferior olivary nuclei
A
Receives motor input from cerebral cortex and has efferent connections with cerebellum to regulate cerebellar motor learning
16
Q
Posteriorly on the medulla, there’s an open and closed medulla - which of these is superior
A
Open medulla
17
Q
What structure does the open part of the medulla open into
A
IV ventricle
18
Q
2 surface features of the pons
A
CN V
Middle cerebellar peduncle
19
Q
What kind of fibres is the middle cerebellar peduncle made of
A
Purely afferent (Sensory) fibres
20
Q
Inferior cerebellar peduncle connects what with what
A
Medulla with cerebellum
21
Q
Middle cerebellar peduncle connects what with what
A
Pons with cerebellum
22
Q
Superior cerebellar peduncle connects what with what
A
Midbrain with cerebellum
23
Q
Surface features of the midbrain
A
Cerebral peduncles
Superior and inferior colliculi
24
Q
What fibres are the cerebral peduncles made of
A
Sensory + motor, but mostly motor
25
What do the cerebral peduncles connect
Midbrain with thalamus and thereby the cerebrum
26
Function of superior colliculi
Involved in visual reflex
27
Function of inferior colliculi
Involved in auditory reflex
28
4 components of the diencephalon
Thalamus, hypothalamus, subthalamus and epithalamus (pineal gland)
29
Diencephalon is immediately superior to what
Midbrain
30
Name the surface projections on the surface of the hypothalamus
Mamillary bodies
31
Another name for epithalamus
Pineal gland
32
Name the thing connecting the 2 cerebellar hemispheres in the midline
Vermis
33
Name the 3 lobes of each cerebellar hemisphere
Anterior lobe
Posterior lobe
Flocculondular lobe
34
Name the extra lobe like structure of each cerebellar hemisphere inferiorly
Cerebellar tonsil
35
Name the space anterior to the cerebellum and posterior to brainstem
IV ventricle
36
Cerebellum sits above what foramen
Foramen magnum
37
What components of the cerebellum sit above the foramen magnum
Cerebellar tonsils
38
Clinical significance of cerebellar tonsils
When intracranial pressure suddenly drops, the cerebellar tonsils can herniate down through foramen magnum, compressing lower brainstem and the first part of spinal cord = CEREBELLAR CONING
39
Posterior inferior cerebellar artery occlusion causes what syndrome
Lateral medullary syndrome
40
What fissure separates the 2 cerebral hemispheres
Median longitudinal fissure
41
What fold of dura lies in the median longitudinal fissure
Falx cerebri
42
What massive white matter tract structure connects the 2 cerebral hemispheres
Corpus callosum
43
Function of corpus callosum + what fibres it carries
Made up of commissural fibres that allow communication between the right and left side
44
The cerebral hemispheres sit on which 2 cranial fossae + what sits on the remaining cranial fossa
Anterior and middle
| Cerebellum sit on the posterior cranial fossa
45
What fold of dura mater do the cerebral hemispheres sit above in the posterior cranial fossa
Tentorium cerebelli
46
Name the fissure that divides the frontal and parietal lobe superiorly and the temporal lobe inferiorly
Lateral fissure
47
Name the sulcus that divides the frontal and parietal lobe (primary motor cortex from primary somatosensory cortex)
Central sulcus
48
Name the sulcus on the MEDIAL surface of the cerebral hemispheres that divides the parietal and occipital lobe
Parieto-occipital sulcus
49
Name the sulcus on the MEDIAL surface of the cerebral hemisphere that extends anteriorly from the parieto-occipital sulcus to the occipital pole posteriorly
Calcarine sulcus
50
Name the 3 poles of the cerebral hemispheres
Frontal pole
Temporal pole
Occipital pole
51
Which lobe contains the primary motor cortex
Frontal
52
Which lobe contains the primary visual cortex
Occipital
53
Which lobe contains the primary somatosensory cortex
Parietal
54
Which lobe contains the primary auditory cortex
Temporal
55
What parts of the vertebrae are removed in a laminectomy
Lamina + spinous process
56
What muscle overlies the lamina of the vertebrae
Erector spinae
57
What 4 ligaments might be encountered in a laminectomy
Ligamentum flavum
Interspinous
Supraspinous
Posterior longitudinal
58
Function of ligaments flavum
Connects laminae of adjacent vertebrae
| Broad pale yellow fibrous tissue appearance
59
Function of interspinous ligament
Connect adjoining spinous processes and extend from the root to apex of spinous processes
60
Function of supraspinous ligament
Connects the tips of spinous processes from C7 onwards
61
Function of posterior longitudinal ligament
Connects the posterior surface of vertebral bodies and IV discs; mainly connected to IV discs, less so bodies
62
What level does spinal cord end in adult
L1-L2
63
What level does spinal cord end in newborn
L3
64
What level does the dura mater end
S2
65
What level does the arachnoid mater end
S2
66
What happens to the Pia mater inferior to the spinal cord
Extends as the filum terminale
67
What occupies space between conus medullaris and the termination of the dura and arachnoid mater
Cauda equina (nerve roots of L2- Cc1)
68
Clinical significance of the caudal equina
Where to do lumbar puncture
69
What vertebral level would you do lumbar puncture
Between L3 and L4
70
How many pairs of spinal nerves + describe how many of each
31 pairs - 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
71
Lower motor neurone lesion is in where
In spinal nerves that have left the spinal cord (i.e. spinal nerve roots)
LMNs in the ventral horn of spinal cord
72
Upper motor neuron lesion is in where
CNS - brain and spinal cord
73
Is damage to the caudal equina an UMN or LMN lesion
LMN
74
Name the arteries entering the cranial cavity to supply the brain
Right and left vertebral arteries
75
What happens to the vertebral arteries after entering the foramen magnum
They fuse once they've entered the cranial cavity to form basilar artery
76
Basilar artery terminates as what 2 arteries
Right and left posterior cerebral arteries
77
Name the small branch that comes off the vertebral arteries before they fuse
Posterior inferior cerebellar arteries
78
Name the 3 main branches of the basilar artery from posterior to anterior before terminating as the posterior cerebral arteries
Anterior inferior cerebellar a
Labyrinthine a
Superior cerebellar a
79
What does the posterior communicating artery join
The posterior cerebral a to the middle cerebral/ICA (as MCA is branch of ICA)
80
What does the anterior communicating artery join
The 2 anterior cerebral arteries
81
How many posterior and anterior communicating arteries are there
2 posterior
| 1 anterior
82
What cerebral arteries are branches of the ICA
Middle and anterior cerebral
83
Name the arteries forming the circle of willis (4 are paired) that supply the brain
1. L+ R INTERNAL CAROTID ARTERY
2. L+ R ANTERIOR CEREBRAL ARTERY
3. ANTERIOR COMMUNICATING ARTERY
4. L+ R POSTERIOR CEREBRAL ARTERY
5. L + R POSTERIOR COMMUNICATING ARTERY
84
Protective function of circle of willis
If one of the arteries that make up the circle of Willis occluded, ischaemia can be prevented because the other arteries would compensate for it by preserving cerebral perfusion through COLLATERAL CIRCULATION
85
Which arteries do the left and right vertebral arteries arise from
Left and right subclavian
86
What level range do the left and right ICAs arise
C3 - C5
87
Which part of brainstem is basilar artery related to
Lies on pons
88
What fissure does the ACA lie in
What sulcus does the MCA lie in
What fissure does the PCA lie in
Median longitudinal fissure
Lateral sulcus
Transverse/horizontal fissure (between cerebellum and occipital lobe)
89
```
Which cerebral artery supplies the:
Primary motor cortex
Primary somatosensory cortex
Primary visual cortex
Primary auditory cortex
Olfactory area
```
```
MCA
ACA & MCA
PCA
MCA
MCA?
```
90
What parts of brain does the vertebra-basilar system supply
Brainstem
Cerebellum
Occipital lobes
91
Which arteries runs superior to superior cerebellar arteries
PCAs
92
Which cranial nerve emerges just above superior cerebellar artery
CN III
93
Aneurysm of PCA often results in palsy of what closely anatomically related nerve
CN III
94
Features of CN III palsy
SR, IR, MR, IO wouldn't function normally
| LR and SO can still abduct and depress so eye is typically in down and lateral position
95
What 3 things help to control blood flow to brain
Carotid sinus
Carotid body
Sympathetic motor nerves
96
What is the carotid sinus anatomically + function + what nerves are sensory to it
Dilatation on the terminal part of the CCA/proximal part of ICA
Is a pressure receptor which monitors blood flow to brain
Glossopharyngeal and vagus
97
What is the carotid body anatomically + function + what nerves are sensory to it
Area on the posterior wall of the terminal part of CCA
Contains chemoreceptors which are sensitive to low oxygen (hypoxia), if hypoxia detected then heart rate, respectively rate and blood pressure stimulated to increase
Glossopharyngeal
98
How are sympathetic motor nerves involved with the ICA
Sympathetic motor nerves from the superior cervical ganglion form a plexus around the ICA and enters the skull with the ICA through the carotid canal
99
Venous drainage of the brain
By a series of smaller veins which drain into dural venous sinuses
100
Dural venous sinuses are located between what 2 layers
Cranial dura and the periosteum (inner surface of skull)
101
Name a cerebral vein belonging to the deep group of cerebral veins that can be seen on specimen
Great cerebral vein
102
What major vein do dural venous sinuses drain into and through which foramen of the skull does this vein exit
IJV
| Jugular
103
Name the veins that connect the intracranial venous sinuses with extra cranial veins (3) + clinical significance of these
Superior ophthalmic vein
Emissary veins
Inferior petrosal sinuses
Potential routes of infection carried in the blood towards the brain
104
Superior ophthalmic vein drains into what
Cavernous sinus
105
What are emissary veins + clinical significance of these
Small veins that connect the dural venous sinuses with the dipole of the skull which contains blood sinuses (in the bone marrow of the dipole) that are continuous with veins in the superficial fascia of the outer part of skull and scalp
Spread infection into brain
106
What sinus connects the 2 inferior petrosal sinuses
Basilar sinus
107
Name some dural venous sinuses (8)
```
Superior saggital
Inferior saggital
Transverse
Sigmoid
Cavernous
Straight
Superior petrosal
Inferior petrosal
```
108
What bony part of the skull does the confluence of sinuses occur
Internal occipital protuberance
109
Location of cavernous sinus
On either side of the sella turcica
110
What vein drains into cavernous sinus
Superior ophthalmic
111
What neurovascular structures run in the cavernous sinus (6)
ICA
| CN III, IV, VI, V1, V2
112
What structures in skull base is cavernous venous sinus closely related to (3)
Pituitary gland
Sphenoid air sinus
CN II
113
Serious disease associated with cavernous sinus + describe it
Cavernous sinus thrombosis
| Sphenoid air sinus can spread infection into the cavernous venous sinus if a fistula forms between them
114
Clinical features of cavernous sinus thrombosis
Bulging eyes
Loss of vision (due to impaired venous drainage from orbit + eye --> retinal congestion --> papilloedema or retinal haemorrhages)
115
Arterial supply to spinal cord
Anterior spinal artery to anterior spinal cord
| Posterior spinal artery to posterior spinal cord
116
Branches of which arteries fuse to form the anterior spinal a
Vertebral a
117
Posterior spinal a is branch of
Vertebral OR PICA - variable in people
118
What venous plexus lies in the epidural space + what 2 veins join the plexus
```
Internal vertebral (epidural) venous plexus
Anterior and posterior spinal veins
```
119
The internal vertebral venous plexus passes superiorly within the vertebral canal through the .... to communicate with dural sinuses and veins within the skull
Foramen magnum
120
The internal vertebral venous plexus also communicates with what other plexus on the external surface of the vertebrae
External vertebral venous plexus
121
3 layers of meninges
Dura mater
Arachnoid mater
Pia mater
122
What circulates in the subarachnoid space
CSF
123
What fold of dura is in the midline + what does it separate
Falx cerebri
The 2 hemispheres
124
What bony structures does the falx cerebri attach anteriorly and posteriorly to
Anterior - crista galli
Posterior - internal occipital protuberance
125
Name the 4 folds of dura in the brain
Falx cerebri
Tentorium cerebelli
Falx cerebelli
Diaphragma sellae
126
What dural sinus runs in the upper border of the falx cerebri
Superior saggital
127
What dural sinus runs in the lower border of the falx cerebri
Inferior saggiata
128
What structures lie on either side of the tentorium cerebelli
Occipital lobes and cerebellum
129
What bony points does the anterior edge of the tentorium cerebelli attach to
Clinoid processes of sphenoid bone
130
What dural venous sinus runs along the attachment of the falx cerebri to the tentorium cerebelli
Straight sinus
131
What dural fold separates the two cerebellar hemispheres
Falx cerebelli
132
What dural fold surrounds the pituitary stalk
Diaphragm sellae
133
Arterial supply of dura mater (3) + name a clinically significant artery that is branch of the maxillary artery that supplies the dura
Branches of ICA, ECA and vertebral a
Middle meningeal
134
What is the middle meningeal artery a branch of
Maxillary artery which is a branch of ECA
135
Formane that middle mengineal artery traverses
Foramen spinosum
136
What are ventricles in the brain
CSF filled cavities
137
What are ventricles of the brain embryologically derived from
Lumen of neural tube
138
Name the ventricles + what connects the ventricles to each other
Lateral (2)
3rd
4th
Lateral connected to 3rd by inter ventricular foramen (foramen of munro)
3rd connected to 4th by cerebral aqueduct (of sylvius)
139
What part of the brain do these parts of the lateral ventricles lie in:
- anterior horn
- body
- inferior horn
- posterior horn
Anterior horn - frontal lobe
Body - under corpus callosum
Inferior - temporal lobe
Posterior - occipital lobe
140
What part of the brain is the 3rd ventricle in
In the diencephalon, between R + L thalamus
141
What part of the brain is the cerebral aqueduct in
Midbrain
142
Where is the 4th ventricle
Posterior to pons + medulla but anterior to cerebellum
143
What specialised structures in the ventricles produce CSF
Choroid plexus
144
How does CSF pass into subarachnoid space from 4th ventricle (hint: 2 foramina)
Passes through small holes called the the foramen of Magendie (more medial) and the foramen of Luschka (more lateral) in the roof of the 4th ventricle into the subarachnoid space
145
How is CSF resorbed once in the subarachnoid space
Via arachnoid villi which protrude into the walls of the superior saggital sinus usually
146
If CSF circulation restricted --> increase in ICP; in infants congenital defects in circulation of CSF can occur leading to enlargement of the head because ventricles dilated --> degeneration of surrounding brain tissue; what is this called
Hydrocephalus
147
What surgical procedure can be carried out for hydrocephalus + why
Shunt to redirect fluid out of cerebral circulation into deep venous system
148
What dural fold separates the occipital lobes from the cerebellum
Tentorium cerebelli
149
What does cingulate gyrus separate
Separates the frontal and parietal lobes from the cingulate gyrus on the medial surface of the hemisphere
