Dissection Flashcards
1
Q
What are the 3 Cranial Meninges in Order from outside in
A
Dura Mater, Arachnoid Mater, Pia Mater
2
Q
Structure of Dura
A
Fibrous Sheet
2 layers- Inner meningeal, outer endosteal
3
Q
Name the 3 main Dural Folds
A
Falx Cerebri- separates hemispheres
Tentorium Cerebelli- Separates Cerebellum from Rest of Brain
Falx Cerebelli- Separates the 2 cerebellar hemispheres
4
Q
Describe the structure of Arachnoid Mater
A
poorly vascularised, loose connective tissue, loosely enveloping the brain.
Skims over sulci- subarachnoid space below with cisterns filled with CSF
5
Q
What are granulations?
A
Calcified arachnoid poking through to venous sinus’ for the reabsorption of CSF
6
Q
Describe the inner layer of Pia Mater
A
Formed by astrocyte end-feet covered with basement membrane
7
Q
Describe the outer layer of Pia Mater
A
Transverses through subarachnoid space
8
Q
What are the names of the connections between Pia ad Arachnoid?
A
Trabeculae
9
Q
Are blood vessels found in all layers of Cranial Meninges?
A
Yes
10
Q
Where’s an extradural Haemorrhage?
A
Outside Dura (inside skull)
11
Q
where’s a subdural haemorrhage?
A
between dura and arachnoid
12
Q
Where’s a subarachnoid haemmorhage?
A
Below arachnoid (in SA space)
13
Q
Where’s an intracerebral Haemmorhage?
A
in brain tissue
14
Q
What tends to cause extra- and sub- Dural haemorrhage?
A
Traumatic head injury
15
Q
What tends to cause subarachnoid and intracerebral haemmorhage?
A
Stroke/ vascular incident
16
Q
What makes up Dural venous sinuses?
A
Gaps between endosteal and Meningeal dural layers
17
Q
What drains into dural venous sinuses?
A
External cerebral veins
18
Q
Name of sinus along top of falx cerebri
A
Superior Sagittal Sinus
19
Q
Name of sinus inferior to falx cerebri
A
Inferior sagittal sinus
20
Q
Describe the route of blood from the sagittal sinus’
A
Inferior SS goes back through straight sinus, the straight sinus meets superior sagittal sinus at the confluence of the sinuses, then flows sideways along transverse sinus, down sigmoid sinus and drains into jugular vein
21
Q
Which cranial nerves are found in the cavernous sinus?
A
3,4,5a and 5b
22
Q
which artery is found in the cavernous sinus
A
internal carotid
23
Q
What are the 2 main openings from the 4th ventricle allowing CSF passage out?
A
Foramen of Magendie and Foramina of Luschka
24
Q
Is the Foramen of Magendie lateral or medial?
A
Medial
25
Are the Foramina of Luschka lateral or medial
Lateral
26
Where is the interpeduncular cistern found?
Ventral to midbrain cerebral peduncles
27
What does the interpeduncular cistern contain?
Circle of Willis
28
What does the cistern of the lateral fissure contain?
Middle Cerebral artery
29
What does the superior cistern contain?
Great Cerebral Vein (of Galen) and the Pineal Gland
30
Where is the superior cistern found?
Between Splenium of CC and Cerebellum
31
What to the Cisterna Ambient encircle?
The midbrain
32
What are the 3 contributors to the BBB
1- Endothelial Cells
2- Basement Membrane
3- Astrocytic End-feet
33
What are the 2 possible routes for blood into the brain?
Internal Carotid Arteries or Vertebral Arteriest
34
The Vertebral arteries fuse to form..
The basilar Artery
35
What proportion of blood do the internal carotids supply?
80%
36
What proportion of blood do the vertebral arteries supply?
20%
37
What brain areas does the internal carotid supply?
anterior and middle cerebrum and the diencephalon
38
What brain areas does vertebral arteries suuply?
Posteriors Cerebrum (occipital) and posterior cranial fossa (brainstem and cerebellum)
39
Where do the vertebral arteries enter into skull?
Foramen of Magnum
40
How are the Vertebro-basilar and internal carotid arteries conected?
Via the posterior cerebral artery
41
Where does the Anterior Cerebral Arteries supply?
Medial Territories (about a 1cm strip from the longitudinal fissure)
(it loops over corpus callosum supplying it also)
42
What connects the left and right anterior cerebral arteries?
Anterior communicating artery
43
Which is the largest branch of the carotid artery?
Middle cerebral artery
44
What does the middle cerebral artery supply?
Lateral territories of hemispheres
45
What does the posterior cerebral artery supply?
posterior and inferior medial surfaces of temporal lobes and the occipital lobes
46
what are the 3 arteries that supply the cerebellum?
1- posterior inferior
2- anterior inferior
3- superior cerebellar
47
What are internal cerebral veins?
Veins which run within the substance of brain tissue until they reach the surface
48
How do intracranial venous sinuses communicate with veins outside of the skull?
via emissary veins
49
Where do the internal carotid arteries enter the skull?
Through the carotid canal- laterally through temporal bone not a straight path
50
Where do spinal arteries pass out of skull?
Foramen Magnum
51
Out of which skull foramina does venous blood drain?
Jugular foramina (through internal jugular vein)
52
how does the Ophthalmic artery enter the skull
through the optic canal
53
Where do the ethmoidal artery and vein get into the skull?
anterior nasal cavity
54
Where does the superior ophthalmic vein enter the skull?
Superior orbital fissure
55
Where does the middle meningeal artery enter the skull?
Foramen Spinosum
56
Where does the labyrinthine artery enter the skull?
Internal acoustic meatus
57
What is a berry aneurysm?
Out-pouching sac of intercranial artery- enlarges until it ruptures
58
Where is a ischaemic stroke?
Intracerebral
59
Where is a Haemorrhagic stroke?
Subarachnoid
60
What is Wallenberg Syndrome?
Blockage of vertebral artery or PICA
61
What are the 3 cranial fossa?
Anterior, Middle, Posterior
62
What brain structure is contained in the anterior fossa?
Frontal Lobe
63
What brain structure is contained in the middle fossa?
Temporal Lobe
64
What brain structure is contained in the posterior fossa?
Cerebellum
65
Where does the anterior cranial fossa end and the middle begin?
Lesser wing of sphenoid bones
66
What attaches to the crista galli on the cribiform plate of the ethmoid bone?
Falx cerebri
67
Where in the skull does the trigeminal nerve split to 3?
Mikkel's cave
68
What is the defining feature of the foramen lacerum?
Jaggedy edge outside skull
69
Which cranial nerves pass through the superior orbital fissure?
3rd, 4th, 5a (ophthalmic) and 6th
70
Which cranial nerve passes through the foramen rotundum?
Maxillary of Trigeminal
71
Which cranial nerve passes through foramen ovale?
Mandibular trigeminal (its sensory and motor branches side by side, hence wider oval shape)
72
What attaches to the ridge of the petrous part of the temporal bone?
Tentorium Cerebelli
73
Which cranial nerves exit via the foramen jugular?
9th, 10th, 11th
74
which cranial nerves exit via internal acoustic meatus?
7th and 8th
75
How many cervical, thoracic, lumbar and sacral vertebrae of the spine?
7C, 12T, 5L, 5S (fused)
76
Which vertebrae supports the weight of the skull
1st cervical- Atlas (greek god atlas supported weight of the planet)
77
Which vertebrae has the aduntoid peg from its vertebral body around which the neck can rotate?
2nd cervical- Axis
78
Which type of vertebrae have long downward pointing spinous processes?
Thoracic
79
Which types of vertebrae have costal facets?
cervical and thoracic (to attach to ribs)
80
Which vertebrae have bifid spinous processes?
C1-C6
81
Does the size of vertebrae increase or decrease moving down spine?
INcrease
82
How many curves in adult spine?
3
83
What do you call a forward spine curve?
Lordosis (cervical and lumbar)
84
What do you call a backwards spine curve?
Kyphosis- thoracic
85
What connects the vertebral bodies above and below?
intervertebral discs
86
What connects articular processes?
Synovial joints
87
What are the 2 types of cartilage in the disc?
Hylin and Fibro cartilage
88
what connects bodies of spinous processes?
Interspinous ligaments
89
What connects tips of spinous processes?
Supraspinous ligament
90
Define Filum Terminale
tube of pia that continues from the conus medullaris down to the coccyx
91
At which vertebral point does the spinal cord end?
L1-L2
92
How many of each segment of the spinal cord are there?
Cervical- 8
Thoracic- 12
Lumbar- 5
Sacral- 5
Coccyx- 1
93
What is found in the dorsal root ganglia?
The cell bodies of the sensory neurons
94
Does the length of nerve roots increase or decrease going down the spinal cord?
Increase
95
Which spinal cord section has the largest grey matter in cross-section?
sacral
96
Which spinal cord section has smallest grey matter in cross-section?
cervical
97
Which spinal cord section has smallest white matter in cross section?
Sacral
98
which spinal cord section has largest white matter in cross section?
cervical
99
technical term for midbrain
mesencephalon
100
Which Cranial Nerve nuclei are found on midbrain?
oculomotor (III) and trochlear (IV)
101
Which Cranial Nerve nuclei are found on the pons?
V-VIII
trigeminal, abducens, facial, vestibulocochlear
102
Which cranial nerve nuclei are found on the medulla
VIII-XII
Vestibulocochlear (found between pons and medulla), Glossopharyngeal, Vagus, Accessory, Hypoglossal
103
What is the bulbo-pontine sulcus?
junction between pons and medulla
104
what's the basilar sulcus
groove running along the midline ventral surface of the pons
105
what's the anterior median fissure?
Groove running along the midline ventral medulla
106
Where are the pyramids found?
either side of the anterior median fissure on of the medulla
107
Where are the olives found?
Lateral to pyramids on the medulla
108
what's the ventrolateral sulcus
sulcus separating the pyramids and olives
109
Which cranial nerve's rootlets exit on the ventrolateral sulcus on the medulla?
Hypoglossal
110
What does the inferior cerebellar peduncle connect?
medulla and cerebellum
111
What does the middle cerebellar peduncle connect?
pons and cerebellum
112
what does the superior cerebellar peduncle connect?
midbrain and cerebellum
113
Are the cerebellar peduncles afferent, efferent or both?
both- bidirectional
114
What are the bumps on the anterior midbrain?
cerebral peduncles
115
what are the 4 bumps on the posterior midbrain
colliculi
116
what's the latin word for the 4 colliculi?
corpora quadremina
117
what sense are the superior colliculi involved in?
Visual
118
what sense are the inferior colliculi involved in?
Auditory
119
what is the cut off line between the ventral tegmentum and dorsal tectum of the midbrain?
cerebral aqueduct
120
what does the substantia nigra overlie
the crus cerebri
121
Does the medial geniculate body of the thalamus relay visual or auditory information?
auditory
remember MALE
122
Does the lateral geniculate body of the thalamus relay visual or auditory information?
visual
remember MALE
123
what is the locus coereleus
a nucleus in the upper pons of noradrenergic neurons with extensive connections to forebrain, brainstem, spinal cord, cerebellum etc.
neuromelanin- dark
124
is the optic chiasm anterior or posterior to pituitary gland?
anterior
125
where do oculomotor and trochlear neurons arise?
the junction of midbrain and pons
126
what does someone's eyes look like with a dysfunctional ocular motor cranial nerve?
eyes looking down and out
127
Describe the structure of the cerebellum
2 ovoid hemispheres joined in the middle by narrow vermis
Outer grey matter layer (cortex), inner WM, surrounding central deep nuclei
Folia folding- as opposed to sulci/gyri
Tonsils
Each hemisphere has 2 lobes- anterior and posterior separated by primary fissure
Flocculus
128
what is the role of the flocculonodular lobe?
primarily balance and eye movement
129
What are the 3 main inputs to the cerebellum?
- corticopontocerebellar - info from primary motor cortex via the middle peduncle (pons)
- Vestibulocerebellar- vestibular impulses from labyrinths (inner ear) via inferior peduncle (medulla)
- Spinocerebellar- sensory input for balance and position sense (proprioception) from superior peduncle (midbrain)
130
What's the largest deep-brain nuclei in the cerebellum?
dentate nucleus
131
Where does the output of the dendate nucleus go?
out via superior peduncle to the red nucleus of the midbrain to the thalamus and then motor/premotor cortices
132
Describe motor planning in the cerebellum
corticopontine inpts to lateral cerebellar hemispheres involved in motor planning, with output via dendate to thalamus - motor and premotor cortices
133
describe motor execution in the cerebellum
involves vermis and medial regions of cerebellum recieving sensory inputsfor motor execution
output via gastigial and interposed nuclei to medial and lateral descending systems respectively
134
what forms the floor of the 4th ventricle?
rhomboid fossa
135
is gracile tubercle lower or upper limb?
lower
136
is cuneate tubercle lower or upper limb?
upper
137
what is the line down the middle of the rhomboid fossa?
median sulcus
138
what are the gracile and cuneate tubules part of?
dorsal medium lemniscus column
139
what is the dorsal medium lemniscus column function
sensory-
fine touch, vibration, 2-point discrimination and proprioception
140
what's the medullary striae?
pontocerebellary fibres running from the pons to cerebellum
141
What is the obex?
inferior tip of rhomboid fossa- inside is area postrema- nausea response to toxins
142
what's the hypothalamic sulcus?
demarkation between thalamus and hypothalamus
143
where is the lamina terminalis
anterior to hypothalamus, keeping CSF of 3rd ventricle in
144
what structures make up the epithalamus?
posterior commisure (posterior inferior to thalamus), habenula (above) and pineal body (above)
145
what separates the anterior horns of the lateral ventricle?
septum pellucidum
146
How does CSF travel from lateral ventricle to 3rd ventricle?
intraventricular foramen/ foramen of munroe
147
what's the rostrum
the backward curve from the genu of the corpus callosum
148
what does the fornix connect?
hippocampus with the diencephalon
149
Where is the calcarine sulcus?
at a right angle to the parieto-occipital sulcus
150
describe the papez circuit- starting at hippocampus
hippocampus--> fimbria (hippocampal thickening to form the--> fornix (arches over thalamus) --> fornix columns descend behind hypothalamus and project to the mamillary body--> mammillothalamic tract--> thalamus--> projections out to cingulate gyrus--> back round to parahippocampal gyrus--> entorhinal cortex-->hippocampus
151
what do association fibres connect?
cortical fibres within hemispheres e.g. cingulm bindles from cingulate cortex to parahippocampus)
152
what kind of fibres are internal capsule?
projection fibres
153
what do projection fibres connect?
cortical and subcortical regions
154
breifly describe the olfactory pathway
olfactory epithelium--> olfactory bulb--> olfactory tract --> divides into medial and lateral olfactory striae
155
Describe the lateral olfactory striae
the majority of olfactory projections take this route, goes to the uncus, where the primary olfactory cortex is
also outputs to hippocampus and orbitofrontal cortex via the thalamus
156
what is the function of the lateral olfactory striae?
initial perception and recognition of smells
157
Describe the medial olfactory striae
projections to septal nuclei and olfactory centres via anterior commissure on either side
158
what is the largest bundle of association fibres?
superior longitudinal fassiculus
159
what makes up tthe floor of te inferior horn of the lateral ventricle?
hippocampus
160
what does the caudate nucleus follow?
the curve of the lateral ventricle
161
what does the tail of caudate nucleus touch?
the amygdala
162
what's the name of the anterior bulge of the hippocampus?
pes hippocampi
163
Starting from the lateral ventricle, moving laterally, name the basal ganglia structures
LV- caudate nucleus- internal capsule- globus pallidus medial- medial medullary lamina- globus pallidus lateral- lateral medullary lamina- putamen- external capsule- claustrum- extreme capsule- insula cortex
164
Where is the insula cortex found?
bottom of lateral fissure
165
what makes up the lentiform nucleus?
globus pallidus, putamen and the white matter within this
