Neuroanatomy Flashcards
1
Q
What fundamental functions does our nervous system control, give 4 examples
A
- Consciousness
- Sleep-wake cycles
-Speech and Language
-Judgement
-Reasoning
-Personality
-Self-awareness
2
Q
What is the nervous system made up of
A
-Brain
-Spinal cord
- nerves
3
Q
What protects the spinal cord
A
Vertebral column
4
Q
What protects the brain
A
Skull
5
Q
What is a neuron made up of
A
-Cell body
-Axons
-Dendrites
6
Q
What does Cranial mean in the terms of neuroanatomy
A
Towards the head
7
Q
What does caudal mean in the terms of neuroanatomy
A
Towards the tail end
8
Q
What does rostral mean in terms of neuroanatomy
A
Towards the face
9
Q
How does the central nervous system start within the embryo
A
The CNS first develops as a tube, during the development of the foetus the brain end of the tube grows much larger that the other, the larger is where the brain will be and the smaller will become the spinal cord. Along with as the tube grows, 2 flexures develop in the tube resulting in the brain and spinal cord not orientating along the same axis.
10
Q
What does rostral mean in relation to the brain
A
Anterior
11
Q
What does caudal mean in relation to the brain
A
Posterior
12
Q
What does rostral mean in relation to the spinal cord
A
Superior
13
Q
What does rostral mean in relation to the spinal cord
A
Superior
14
Q
What are the 2 anatomical subdivisions of the nervous system
A
- Central nervous system (CNS)
-Peripheral nervous system (PNS)
15
Q
What is the CNS composed of
A
Brain
Spinal cord
16
Q
What is the peripheral nervous system composed of
A
All nervous tissue outside the CNS, primarily nerves
17
Q
What are the 3 types of nerves found in the PNS
A
Cranial nerves
Spinal nerves
Autonomic nerves
18
Q
What are 2 the functional subdivisions of the nervous system
A
-Somatic nervous system
-Autonomic nervous system
19
Q
What activities does the somatic nervous system control
A
Voluntary activities under conscious control
20
Q
What activities does the Autonomic nervous system control
A
Involuntary activities not under conscious control
21
Q
What are the 3 main parts of the brain
A
-Cerebrum
-Cerebellum
-Brainstem
22
Q
What is the Cerebrum?
What is it composed of?
How many parts is it split into?
A
-Largest part of the brain
-Composed of lots of neurones and supporting cells
-Has right and left cerebral hemispheres which are connected
23
Q
What is the surface of the cerebrum called?
What does this layer contain?
What colour does this layer appear?
A
- Cerebral cortex
-Neuron cell bodies
-Grey (grey matter)
24
Q
What happens in grey matter?
A
Information is processed
25
What are the folds called found in the cerebral cortex?
What are the grooves between the folds called?
-Gyri (singular= gyrus)
- Sulci (singular= sulcus)
26
What is found in the cerebral hemispheres?
-Masses of axons
-Collections of cell bodies (called nuclei)
27
What colour are the axons in the cerebral hemispheres?
White/pale in appearance, this is known as white matter
28
What happens within the white matter?
Information is transmitted through bundles of fibres
29
Name the 4 anatomical lobs the cerebral hemispheres are divided into
-frontal
-parietal
-occipital
-temporal
30
Where is the frontal lobe found
The large frontal lobe lies anteriorly
31
Where does the occipital lobe lie
The occipital lobe lies posteriorly
32
Where can the parietal and temporal lobes found
These two lobes lie between the frontal and occipital lobes
33
What is the cerebellum known as?
Where is it found?
-the cerebellum is known as the little brain
- The cerebellum lies inferiorly too the posterior part of the cerebrum
34
How many parts is the cerebellum divided into?
- 2, left and right hemispheres connected to each other
35
What is the surface of the cerebellum like?
Highly folded
36
What does the cerebellum contain
White matter and nuclei
37
What is the cerebellum attached to
The brainstem
38
What is the function of the cerebellum
Functions in
-balance
-coordination
-movement
39
Does the cerebellum work in our conscious or unconscious control
Unconscious control
40
What are the 3 parts of the brain stem
-The midbrain
-The pons
-The medulla
41
Where can the brainstem be found
The brainstem lies inferior to the cerebrum but anterior to the cerebellum, and is attached to both
42
What is the brainstem function
-Relays information between the cerebrum, spinal cord and cerebellum
-Gives rise to cranial nerves
-Contains centres that regulate breathing and consciousness
43
What is the spinal cord continuous with
Medulla
44
Where does the spinal cord end in relation to the vertebral column
The spinal cord is shorter than the vertebral column ending at around L1/2
45
What is the grey matter in the spinal cord
The grey matter in the spinal cord are neuronal cell bodies
46
What does the white matter consists of in relation to the spinal cord
The white matter surrounds the grey matter in the spinal cord and contains tracts
47
What are Tracts in the spinal cord
Tracts are bundles of axons that connect different parts of the CNS to each other
48
How many pairs of spinal nerves are there
31 pairs all attached to the spinal cord
49
What does each pair of spinal nerves do
Each pair corresponds to a segment within the spinal cord which carry information between the cord and the periphery such as skin and muscle
50
What are ventricles in relation to the brain
Ventricles are cavities inside the brain filled with Cerebrospinal fluid (CSF)
51
How does CSF leave the ventricles
CSF leaves the ventricles through small openings and surrounds the brain and spinal cord
52
What is the function of CSF
-provides nutrients
-protects (acts as cushion against any trauma)
-Prevents nerves becoming compressed between the brain and skull
53
What are the 3 membranes called that lie between the brain and spinal cord and the bones
The meninges
54
What are the names of the 3 meninges
-Dura mater
-Arachnoid mater
-Pia mater
55
What is the dura mater
The dura mater is the inner surface of the skull (so most outer layer of meninges) it is thick and strong
56
What is the arachnoid mater
This lies deep in from the dura, is thin and loosely encloses the brain and spinal cord
57
What is the Pia mater
The Pia mater is the inner most meninges membrane and is adhered to the surface of the brain and spinal cord, It is very thin
58
What is the function of the meninges
-Protects the brain
-provides scaffold for the blood vessels
59
What are the 2 pairs of arteries that supply the brain
- the left and right internal carotid arteries
- the left and right vertebral arteries
Both pairs ascend to the brain via the neck
60
On the inferior of the cerebrum the arteries give rise to branches which form an interconnected ring- what is this ring called
The circle of Willis
61
What is the circle of Willis an example of
Anastomosis
62
What is anastomosis
Anastomosis is where branches from separated arteries unite with each other
63
Theoretically what does anastomosis allow
Anastomosis allows for the blood supply to an area to be maintained even if on vessel which supplies it becomes blocked
64
What can be found above the circle of Willis
-3 Cerebral arteries
- cerebellar arteries
- Arteries that supply the brainstem and spinal cord
65
Where can veins be found within the brain
Veins drain blood from the brain, there are deep and superficial veins and also veins found in the dura mater called dura venous sinuses
66
What does the motor component of the somatic nervous system do
The motor component controls the voluntary contraction of the skeletal muscle eg-movement of limbs
67
What does the sensory component of the somatic nervous system do
The sensory component sends information about peripheral stimuli from sensory receptors in the body to the CNS which then reaches our conscious perception eg-pain
68
What does the motor component of the autonomic nervous system do
The motor component control smooth muscle, glands and cardiac muscle and is divided into 2
69
What are the 2 subdivisions of the motor component of the autonomic nervous system
-Sympathetic nervous system
-Parasympathetic nervous system
70
What does the sensory component in the autonomic nervous system do
The sensory component conveys sensory information about the internal environment from the viscera to the CNS but doesn’t reach our conscious perception eg-blood pressure monitoring
71
What are sympathetic and parasympathetic nerves also known as
Visceral efferent nerves
72
What does the sympathetic nervous system prepare the body for
The 4 F’s
-Fight
-Flight
-Fright
-Freeze
73
What changes happen to the body when the sympathetic nervous system is in play
-Heart rate increases
-Bronchi constrict
-Peripheral blood vessels constrict diverting blood away from the skin/gut to skeletal muscles
-Pupils dilate
-Hairs stand on end
-Sweat glands are stimulated
74
What does the parasympathetic nervous system prepare the body for
Rest and digest
75
What changes happen to the body when the parasympathetic nervous system is in play
-Heart rate decreases
-Bronchi constrict
-Glands are stimulated eg-salivary and digestion
-Peristalsis is stimulated (gut activity)
-Pupils constrict
76
What is the basic organisation of the sympathetic nervous system
-First neuron cell body is in the thoracic or lumbar spinal cord
-Short preganglionic axon
-Second neuron cell body in the ganglion close to the CNS
-Long postganglionic axon
-Target organ/effector eg- smooth muscle of blood vessels
77
What is the basic organisation of the parasympathetic nervous system
-First neuron cell body in the brainstem or sacral spinal cord
-Long preganglionic axon
-Second neuron cell body in a ganglion close to the target organ
-Short postganglionic axon
-Target organ/effector eg-smooth muscle in wall of intestine
78
Where is the sympathetic ganglia
The sympathetic ganglia is closer to the CNS than the target organ meaning the preganglionic axons are short
79
Where is the parasympathetic ganglia
The parasympathetic ganglia is closer to the target organ sometimes even within the target organ so the preganglionic axon is long
80
Which system out of the sympathetic or parasympathetic is most distributed
Sympathetic as the sympathetic nerves innervate the sweat glands and smooth muscle in blood vessel walls and hair follicles (the arrector pili muscles) which reach every part of the body
81
What is the function of the viscera afferent fibres from the autonomic nervous system
-They monitor internal environment eg-blood pressure and levels of oxygen and c02 in our blood, send this information to the CNS which inputs elicit reflex constantly maintaining internal environment
- Convey information to the CNS about distension, stretch, spasm or ischaemia which causes pain and is reached by our consciousness
82
Where can you find the cranial nerves
The cranial nerves arise from the cerebrum and brainstem
83
How many pairs of cranial nerves are there
12 pairs
84
Where do the cranial nerves serve
The head and neck
85
Where do the cranial nerves exit the skull
The cranial nerves exit the skull though the holes in the base Called foramina (singular= foramen)
86
What can cranial nerves be made up of
- they can be made up of purely sensory, purely motor or both and some carry parasympathetic fibres
87
How many pairs of spinal nerves are there
31 pairs
88
How many of each spinal nerve do we have
-8 cervical nerves
-12 thoracic nerves
-5 lumbar nerves
-5 sacral nerves
-1 coccygeal nerve
89
What are spinal nerves composed of
-They are mixed and can carry
Somatic motor fibres from CNS to body
Sympathetic (autonomic motor fibres) from CNS to body
Somatic sensory fibres from body to CNS
90
What are the intervertebral foramina
The gaps in the vertebral column which the spinal nerves pass through
91
Tell me everything about the somatic motor fibres
Somatic motor fibres
The cell bodies of the fibres lie in the ventral horn of the spinal cord, this is the grey matter. The axons leave the cord via rootless which come together to form the ventral (motor) root. These fibres stimulate the voluntary contraction of skeletal muscle
92
Tell me everything about somatic sensory fibres
Somatic sensory fibres
The cell bodies lie in the dorsal root ganglia (DRG), they are small swellings on the dorsal roots. These neurons have 2 processes; one projects peripherally into a spinal nerve and one projects centrally into the dorsal horn
Sensory information travels from peripheral receptors eg-skin towards the DRG via spinal nerves which then travels to the dorsal horn via the rootlets
93
What do sympathetic fibres do
They stimulate the sweat glands and the contraction of smooth muscle
94
What is a dermatome
A dermatome is an area of skin innervated by a single spinal nerve
95
What does a dermatome map show
The map shows the cutaneous territories of each spinal nerve
96
What is a myotome
A myotome is a group of muscles innervated by a single spinal nerve
97
What is the sagittal plane
This is a vertical plane which passes through the length of the sagittal suture of the skull in the long axis of the brain
98
What is a parasagittal plane
This is planes that lie parallel to the sagittal plane but going away from the midline
99
In terms of the brain what does medial mean
Towards the sagittal plane
100
In terms of the brain what does lateral mean
Away from the sagittal plane
101
In terms of the brain what does superior mean
Towards the upper most part of the cerebral hemisphere
102
In terms of the brain what does inferior mean
Towards the base of the brain
103
What does rostral mean
Towards the front of the brain
104
What does caudal mean
Towards the tail of the brain
105
What does dorsal mean in the cerebral hemisphere
Superior
106
What does ventral mean in the cerebral hemisphere
Inferior
107
What is the coronal plane
This goes through the coronal suture of the skull perpendicular to the sagittal plane which divides the front and back of the brain
108
What is the horizontal plane
This intersects both the sagittal and coronal plane at right angles and splits the brain into superior and inferior
109
What is the brain also known as
The encephalon
110
How many parts is the brain divided into
3 parts
111
What are the 3 parts of the brain
The hindbrain
The midbrain
The forebrain
112
What is the hindbrain subdivided into
Medulla oblongata
Pons
Cerebellum
113
What is the medulla oblongata derived from.
The myelencephalon
114
What is the pons derived from
The metencephalon
115
What is the cerebellum derived from
The metencephalon
116
What is the hindbrain also known as
The rhombencephalon
117
What is the midbrain subdivided into
The tectum
The cerebral peduncle
118
Where is the tectum located
This is the part of the midbrain which lies dorsal to the central canal
119
What is the central canal of the tectum also known as
The cerebral aqueduct
120
What does the tectum comprise of
The superior and inferior colliculi
121
What is the superior and inferior colliculi also known as
The corpora quadrigemina
122
Where is the cerebral peduncle located
This is located in the midbrain ventral (inferior) to the cerebral aqueduct
123
What is the cerebral peduncle subdivided into
Dorsal (superior) part the tegmentum
Ventral (inferior) crus cerebri
124
What is the crus cerebri
This is a large fibre tract that runs on each side of the midline of the cerebral peduncle
125
How are the tegmentum and the crus cerebri seperated
They are seperated by a narrow lamina of pigmented cell
126
What is the lamina that seperates the tegmentum and crus cerebri called
The substantia nigra
127
What are the Crura cerebri
They are large bundles of white matter which emerge from the cerebral hemispheres, one on each side of the midline which pass backwards and downwards before converging into the midline at the upper border of the pons
128
What do the crus cerebri form
They form the part of the cerebral peduncle which is visible on the inferior surface of the brain
129
What is the midbrain also known as
The mesencephalon
130
What does the forebrain form
The forebrain forms the majority of the brain
131
What is the forebrain divide into
The diencephalon
The telencephalon
132
What is the diencephalon derived from
This is derived from the anterior part of the developing neural tube
133
What does the diencephalon comprise of
The thalamus
The hypothalamus (with the epi- and sub-thalamus of each side)
134
Where is the telencephalon derived from
This is derived from the cerebral vesicle of each side
135
What does the telencephalon comprised of
It is comprised of an outer layer of grey matter and deep nuclei
136
In the telencephalon what is the outer layer of grey matter also known as
The cerebral cortex
137
In the telencephalon what are the deep nuclei
The basal ganglia
138
What are the meninges
They are 3 separate tubular sheaths of membrane which surround and enclose the entire CNS
139
What are the 3 layers of the meninges
The dura mater
The arachnoid mater
The Pia mater
140
What is the dura mater and what does it comprise
This is the outer most meningeal layer which is a fibrous sheet containing white collagen fibres and a few elastic fibres arranged into dense laminae of often parallel fibres. It can have a lattice like appearance due to the wide angle between each direction of fibres in the adjacent laminae. It is made up of 2 layers the outer endosteal layer known as the periosteum and the inner meningeal layer which is the dura mater proper
141
What is the arachnoid mater and what is it comprised of
The arachnoid mater is a poorly vascularised membrane made up of loose connective tissue consisting of collagen, elastin and reticulum fibres which loosely covers the brain
142
What is the Pia mater and what is it comprised of
The Pia mater is the inner most meningeal layer which adheres to the surface of the CNS following all Gyral and sulcal folds. The inner most layer of pial cells are formed by the underlying end feet of astrocytes with their covering membrane
143
What seperates the pia mater and the arachnoid mater
The subarachnoid space
144
What does the subarachnoid space contain
Cerebrospinal fluid
145
What is white matter
White matter is collections of nerve fibres/axons which are wrapped in a fatty sheath known as the myelin sheath with very little neuronal somata (cell bodies)
146
what is grey matter
Grey matter is formed in the CNS by the aggregations of neuronal cell bodies and their local processes
147
What is the neuropil in relation to grey matter
The neuropil is a network of intermingled and interconnected neuronal processes which occupies space between the cell bodies
148
What colour would you expect myelinated nerves to be
The myelinated nerve fibres would appear white due to the fatty myelin sheaths
149
What colour would you expect the non-myelinated fibres to be
The non-myelinated fibres would expect to be grey due to the lacking of the fatty myelin sheath
150
What are clusters of nerve cell bodies in the brain known as
Nuclei or ganglia
151
What is the cortex and what is it formed of
The outer surface of the brain and is formed by flatter sheets of neurones
152
In the spinal cord where would you find grey matter
In the spinal cord the grey matter makes up the core butterfly shape
153
What does the frontal cortex contain
The primary motor cortex and the prefrontal cortex
154
What is the temporal lobe made up of
Primary auditory cortex, auditory association cortex, hippocampus and amygdala
155
What is the parietal lobe made up of
Primary somatosensory cortex and association cortex
156
What is the occipital lobe made up of
Primary visual and visual association cortex
157
What does the cerebellum control
Motor control of equilibrium, posture and muscle tone and movement co-ordination
158
What is the brain stem made up of
Ascending and descending tracts, Cranial nerve nuclei and the reticular formation
159
What is a gyri
The rolls of the cerebral cortex
160
What are the sulci
The grooves between the gyri
161
What is the central sulcus
A large fissure separating the frontal from the parietal lobe
162
What is the lateral sulcus
A large fissure that separates the temporal lobe from the parietal and frontal lobes
163
What is the occipital pole
This is the posterior most part of the occipital lobe is known as the occipital pole
164
What is the insula
This is the floor of the lateral sulcus
165
What is the opercula
This is the part of the temporal, frontal and parietal lobes which overlie the insula
166
What is the corpus callosum
This is a large bundle of white matter which connects the 2 hemispheres of the brain
167
Where are the olfactory tracts located
They run on the inferior surface of the frontal lobes
168
Where are the optic nerves located
They are seen passing backwards, medially and converging to from the optic chiasma and then pass backwards, and laterally into the optic tracts
169
What is the optic chiasma
The optic chiasma is a place within the brain where optic nerves from one eye come and cross and go to the other eye
170
What are mammillary bodies
They are 2 rounded eminences behind the optic chiasma
171
Where is the hypothalamus located
The hypothalamus is found behind the optic chiasma including the mammillary bodies and is the only part of the diencephalon visible on the outside of the brain
172
Where are the crus cerebri of the cerebral peduncles located
They are located behind the mammillary bodies on each side of from the cerebral hemispheres which then pass backwards converging in the midline at the upper border of the pons
173
What is the interperpendicular fossa
This is the space between the crura roofed over by arachnoid
174
Where is the pons located
The pons is located immediately behind where the crura meet in the midline
175
What is the role of the pons
It provides a bridge of neural tissue between the midbrain and the medulla oblongata
176
What is the cerebellum known as and how many lobes does it have
This is known as the little brain and has 2 lobes
177
Where are the lobes of the cerebellum located
The lobes of the cerebellum are located one either side of the medulla
178
What joins the 2 lobes of the cerebellum together
Central vermis
179
Where is the medulla oblongata located
This runs from the caudal border of the pons to where the spinal cord is
180
Where is the parietal lobe located
The parietal lobe is located from the central sulcus anteriorly to the imaginary parietoocipital fissure posteriorly
181
What area does the parietal lobe contain
The parietal lobe contains the primary sensory area
182
How many parietal lobes are there
2
183
What are the 2 lobes of the parietal lobes
The more dominant left lobe and the non-dominant right lobe
184
What is the dominant left parietal lobe important for
Perception, interpretation of sensory information and formation of the idea of a complex, meaningful motor response
185
Where are the supramarginal and angular gyrus found
They are found in the dominant left parietal lobe
186
What are the supramarginal and angular gyrus important for
They are concerned with language and Mathematical operations
187
What is the non-dominant right partietal lobe important for
Visuospatial functions
188
What is the frontal lobe involved with
Motor function, problem solving, spontaneity, memory, language, judgement, personality, impulse control, social behaviour and sexual behaviour
189
What is the pre-frontal cortex important for
The pre-frontal or anterior portion of the frontal lobe is important for higher cognitive functions and the determination of personality
190
What is the posterior portion of the frontal cortex important for
The posterior portion of the frontal cortex is important for motor and pre motor areas
191
Where is Broca’s area located
Broca’s area is located at the left inferior frontal gyrus
192
What is Broca’s area important for
Language production and comprehension
193
What does the temporal lobe contain
The temporal lobe contains the primary auditory cortex, hippocampus, amygdala and wirnicke’s area
194
Where is wernicke’s area located
Wernicke’s area is located in the superior temporal gyrus of the left hemisphere
195
What is wernicke’s area important for
Understanding spoken words
196
Where is the auditory cortex found in the temporal lobe
The auditory cortex is found around the lateral fissure
197
What is the lateral fissure in the temporal lobe also known as
The Sylvian fissure
198
Where is the occipital lobe located
The occipital lobe is located at the posterior aspect of the brain
199
What does the occipital lobe contain
The occipital lobe contains the primary visual and visual association cortex
200
Where is the limb in system found
The lambic system is found surrounding the medial margin of the hemisphere
201
What does the lambic system include
The hippocampus, fornix, amygdala, thalamus, hypothalamus, basal ganglia and the cingulate gyrus
202
What is the limbic system important for
The limbic system is involved in emotion, memory, behaviour and olfaction
203
What is the hippocampus involved in
The hippocampus is involved in long term memory formation
204
What is the amygdala important in?
The amygdala is important in motivationally significant stimuli such as reward and fear
205
How does the limbic system operate
The limbic system operates via stimulating the endocrine system and autonomic nervous system and is highly interconnected with the brains pleasure centre
206
What is the nucleus accumbens and where is it found
The nucleus accumbens plays a role in sexual arousal and the high experience with recreational drugs
It is found in the limbic system in the basal region
207
Where is the outer endosteal layer found
The outer endosteal layer lines the interior of the skull
208
What is the role of the outer endosteal layer do
It sends blood vessels and fibrous processes into the cranial bones
209
Where is the inner meningeal layer found
The inner meningeal layer is found enveloping the entire CNS continuing as a tube of dura around the spinal cord
210
What is the role of the inner meningeal layer
It provides tubular sheaths for the cranial nerves
211
Is the inner and outer layer of the dura mater continuously fused
No, in places the inner layer seperates from the skull to form dual folds which supports the subdivisions of the brain and partially divide the cranial cavity into 3 areas
212
What are the 3 areas that the dual folds of the inner meningeal layer create
The right hemisphere
The left hemisphere
The posterior cranial fossa
213
What is found in the posterior cranial fossa
The cerebellum
214
What create the dura venous sinuses
Where the dural folds attach to the skull there is a system of communicating blood filled spaces which are known as the dural sinuses
215
What is the falx cerebri
This is an arched crescent of dura lying in the longitudinal fissure between the cerebral hemispheres
216
Where can the superior sagittal sinus be found
The superior sagittal sinus is found where the falx cerebri attaches to the cranium
217
Where can the inferior sagittal sinus be found
The inferior sagittal sinus is found at the free border of the falx cerebri
218
What is the tentorium cerebelli
The tentorium cerebelli is a dura forming thick fibrous roof over the posterior cranial fossa and the cerebellum
219
Where is the straight sinus found
The straight sinus can be found within the tentorium cerebelli at its attachment of the falx cerebri
220
What is the tentorial inscisure
The tentorial inscisure is a horseshoe-shape between the free concave border of the tentorium and the dorsum sellae of the sphenoid
221
Where is the transverse sinus found
The transverse sinus is found running along the line of attachement of the tentorium cerebelli to the occipital bone
222
Where is the cavernous sinus found
The cavernous sinus is found lateral to the body of the sphenoid
223
Where is the trigeminal cave found
The trigeminal cave is found next to the apex of the pet Roy’s part of the temporal bone and envelops the roots of the trigeminal nerve
224
What is the diaphragma sellae
This is a small circular horizontal fold of the dura mater which forms the roof of the pituitary fossa
225
What is the falx cerebelli
The falx cerebelli is a small vertical, sickle shaped reflection of dura separating the two lobes of the cerebellum
226
What is the arachnoid mater
The arachnoid mater is the meningeal layer which encloses the brain loosely following the contour of the meningeal layer of the dura
227
What are the subarachnoid cisterns
Subarachnoid cisterns are spaces found between the arachnoid mater and the pia mater where the arachnoid mater spans the gyri of the brain
228
What is the foramen magenide
The foramen magenide is a midline communication between the 4th ventricle and the subarachnoid space
229
What is the foramen luschka
The foramen luschka is a lateral communication between the 4th ventricle and the subarachnoid space
230
Where is the cerebellomedullary cistern found
This cistern is found in the angle formed by the dorsal surface of the medulla and the inferior surface of the pons
231
Where is the pontine cistern found
The pontine cistern is found on the ventral surface of the pons
232
What does the interpenduncular cistern contain
This cistern contains the circle of Willis
233
What does the cistern of the lateral fissure contain
This fissure contains the middle cerebral artery
234
What is the role of the cistern of the lateral fissure
The cistern of the lateral fissure bridges the lateral sulcus on each side
235
What does the superior cistern contain
The superior cistern contains the greater cerebral vein of Galen and the pineal gland
236
Where is the superior cistern found
The superior cistern is found between the posterior end of the corpus callosum and the superior surface of the cerebellum
237
What are the cisterna ambiens
These are a group of subarachnoid cisterns which completely encircle the midbrain
238
What is the pia mater
The pia mater is the meningeal layer is adhered to the nervous tissue below and Connor be seen with the naked eye
239
Why is the pia mater important
The pia mater is important because it forms part of the blood brain Barrier
240
How does the pia mater act as a barrier between the blood vessels and neurological tissue
On the surface of the brain the arteries lie in the subarachnoid space, as the vessels pass into the substance of the brain they take prolongations of the pia mater and some of the subarachnoid space, which forms a layer around the blood vessel. As the blood vessel penetrates deeper into the brain the tunica media thins and the prolongations of the subarachnoid space narrows. At the level of the capillary network the basement membranes of the endothelial cells of the pia fuse.
241
What does the blood brain Barrier do
The blood brain barrier is a combination of features, unique to the brain and spinal cord that limits the ability of molecules to pass between the blood and CNS which protects the tissues from toxic substances
242
What features protects the tissue from the toxic substances
- tight junctions to prevent molecules passing between the endothelial cells that line the blood vessels
-the basement membrane of CNS lack fenestrations
-pericytes that are found in the basement membrane which wrap around the endothelial cells which regulate capillary blood flow, immunity and vascular permeability
-astrocytes extend processes called end feet that envelop CNS capillaries and restrict flow of molecules into CNS parenchyma
243
What is meningitis
Meningitis is inflammation of the meninges usually caused by an infection
244
Symptoms of meningitis
Headache
Neck stiffness
Photophobia
Nausea/vomiting
Fever
245
What are the 2 types of meningitis
Viral
Bacterial
246
Why is bacterial meningitis more serious than viral meningitis
Bacterial meningitis is where the infection will be circulating in the brain and causing the meninges to become inflamed as it is passing through and so can be life threatening
247
Where is an extradural haemorrhage
what does it cause
When does it occur
Where does the blood come from
An extradural haemorrhage is between the skull and the dura mater. This haemorrhage causes strips of the dura to come away from the skull and compress the brain. This typically is seen after head injury. The blood comes from the meningeal arteries
248
What is a subdural haemorrhage
When is it usually seen
A subdural haemorrhage is found between the dura and the arachnoid mater
This type of haemorrhage is typically seen after a high impact injury such as a car accident
249
What is a chronic subdural haemorrhage
A chronic subdural haemorrhage is seen in the elderly patients 4-8 weeks after a mild/moderate head injury
250
What is a subarachnoid haemorrhage
When is this typically seen
This haemorrhage is seen between the arachnoid and pia mater
This type of haemorrhage is typically seen after ahead injury
251
What happens in a traumatic subarachnoid haemorrhage or rupture of a berry aneurysm
The blood surrounds the brain and fills the sulci near to the site of injury
252
Symptoms of a traumatic subarachnoid/berry aneurysm rupture
Severe sudden headache
253
What is an intracerebral haemorrhage
What is a classic location of this haemorrhage
This haemorrhage is where the rupture of small vessels and micro aneurysms bleed within the brain tissue
Classic location for this is the internal capsule following rupture of the lenticulostriate artery due to high blood pressure
254
What is amaurosis fugax and what causes it
This is the temporary loss of Vision to one eye due to part of the carotid plaque breaks off and occludes the central retinal artery
255
Where are the arteries and veins of the brain found
In the subarachnoid space
256
Why are the superficial cerebral veins easily distinguished
They have a dark colour due to fixed and coagulated blood been visible through the thin walls
257
How can you distinguish arteries in the brain
They looker paler in colour due to having thick muscular walls so they are not easily torn
258
What is the role of the blood brain Barrier and how does it achieve this
The role of the blood brain barrier is to prevent the passage of some substances through to the nervous tissue and it does this through
The endothelial cells of the capillaries
The basement membrane between the endothelial cells and the astrocytic end feet
The astrocytic end feet
259
How does arterial blood enter the brain
The arterial blood enters the vein through the skull via 2 pairs of vessels the internal carotid and the vertebral arteries
260
What percentage of blood do the vertebral arteries supply the brain with
20%
261
What do the vertebral arteries supply in the brain
They supply the posterior cerebrum and the contents of the posterior cranial fossa
262
What percentage of blood do the internal carotid arteries supply to the brain
80%
263
What do the internal carotid arteries supply in the brain
They supply the anterior and middle parts of the cerebrum and the diencephalon
264
Where are the arteries of the brain weak and what can this cause
They are weak at the branches which can cause berry aneurysms
265
Where do the internal carotid arteries arise from
They arise from the bifurcation of the common carotid arteries
266
Where do the common carotid armies bifurcate into the internal carotid arteries
At the level upper border of the thyroid cartilage
267
Where do the internal carotid arteries enter the skull
They enter the skull through the temporal bone and lie in the carotid canal
268
From the carotid canal where do the internal carotid arteries travel
They travel through the dura mater to form the roof of the cavernous sinus to enter the cranial cavity, as they reach the anterior perforated substance at the medial end of the lateral sulcus it divides into its terminal branches and the anterior and middle cerebral arteries. This is known as the anterior circulation
269
Why is the anterior circulation clinically important
The anterior circulation is clinically important as topographically-specific regions of the pre central and post central gyri receive their blood supply via different arteries
270
What do the internal carotid arteries branch into
The internal carotid arteries divide into terminal branches which then become the anterior and middle cerebral arteries
271
What does the anterior cerebral arteries supply
They supply the corpus callosum and the medial aspects of the hemispheres
272
What is the middle cerebral artery and what does it supply
The middle cerebral artery is the largest of the terminal branches of the internal carotid arteries
The middle cerebral artey supplies the majority of the lateral surface of the lateral surface of the hemisphere via its anterior perforating branches
273
What is the anterior communicating artery
This is an artery which connects together the two anterior cerebral arteries and provides the anterior perforating branches
274
What is the posterior communicating artery
The posterior communicating artery connects the internal carotid and vertebra-basilar systems via the posterior cerebral artery
275
What is the circle of Willis
The circle of Willis is a structure which provides an anastomotic connection between the anterior and posterior circulations providing a collateral blow flow to the brain
276
What arteries make up the circle of Willis
The circle of Willis is made up by the left and right internal carotid arteries, left and right anterior cerebral arteries and the left and right posterior cerebral arteries
277
What do the central branches from the circle of Willis supply
The central branches from the circle of Willis supply the deep structures of the hemisphere including the internal capsule
278
The cerebral arteries and the capillaries of the circle of Willis are in continuity but no functional anastamosis between them, why is this clinically important
This is clinically important as infarction of one area does not automatically mean that supply will be taken up by other vessels due to there been no functional anastomosis
279
Where does the vertebral arteries arise from
The vertebral arteries arise from the first part of the subclavian artery
280
Where do the vertebral arteries enter the skull
The vertebral arteries enter the skull through the foramen magnum
281
Where to the vertebral arteries unite
The vertebral arteries unite in the midline at the lower border of the pons
282
What does the vertebral arteries unite to form
The vertebral arteries unite to form the basilar artery
283
Where is the basilar artery found
The basilar artery is found lying in the anterior median fissure on the pons
284
What makes up the posterior circulation
The vertebral and basilar arteries, the branches from them and the posterior cerebral artery are known of the posterior circulation
285
How are the anterior and posterior circulations linked
The anterior and posterior circulations are linked via the circle of Willis
286
What is a berry aneurysm
This is a congenital sac-like out pouching of an intracranial artery which will progressively enlarge until rupturing resulting in a subarachnoid or intracerebral haemorrhage
287
Where do berry aneurysms usually occur
They usually occur on the branches around the circle of Willis, mostly the anterior communicating artery which is found in the sub arachnoid space
288
What are the 2 types of stroke
Ischaemic and haemorrhagic
289
How is blood drained from the brain
Veins in the brain drain blood back to the heart via the dural venous sinuses
290
What are dural venous sinuses
They are channels formed between the two layers of dura mater
291
What are the cerebral veins divided into
Internal cerebral veins and external cerebral veins
292
Where do the internal cerebral veins run
The internal cerebral veins run within the substances of the brain tissue and end when they reach the surface of the brain where they become external cerebral veins
293
Where do the external cerebral veins run
The external cerebral veins run on the surface of the brain crossing the subarachnoid space to drain into the dural venous sinuses
294
Where does the great cerebral vein of Galen drain
This vein drains the deep structures of the brain and drains into the straight sinuses
295
What is the role of the dural venous sinuses
The sinuses connect the major cerebral veins to the internal jugular veins
296
Where can the major venous sinuses be found
The major venous sinuses can be found in the attached borders of the falx cerebri, the tentorium cerebelli and the floor of the cranial cavity
297
Where is the inferior sagittal sinus found
The inferior sagittal sinus is found at the inferior margin of the falx cerebri
298
Where is the superior sagittal sinus found
The superior sagittal sinus is found at the superior border of the falx cerebri
299
Where is the straight sinus found
The straight sinus is found in the midline of the tentorium cerebelli
300
Where is the transverse sinus found
The transverse sinus is found in the posterior fixed margin of tentorium cerebelli
301
Where is the sigmoid sinus found
The sigmoid sinus is found in a deep groove in the mastoid part of the temporal bone
302
Where is the cavernous sinus found
The cavernous sinus is found beside the body of the sphenoid bone
303
What does the cavernous sinus contain
The cavernous sinus contains 5 cranial nerves and the internal carotid artery
304
Where is the superior petrosal sinus found
The superior petrosal sinus is found in the attached lateral margin of the tentorium cerebelli
305
Where is the inferior petrosal sinus found
The inferior petrosal sinus is found in the groove between the petrous temporal bone and the basal part of the occipital bone
306
How do the intracranial sinuses and the veins outside the skull communicate
The intracranial sinuses and veins outside the skull communicate via the variable number of emissary veins
307
Why are the emissary veins important
The emissary veins important as the represent a possible route for infection or inflammation to spread into the cranial cavity from the outside of the skull
308
What can cause venous sinus thrombosis
Venous sinus thrombosis can be caused by rare complications of birth, clotting disorders and ear infections
309
What can obstruction of venous drainage cause
Cerebral odema and raised intracranial pressure
310
What can venous sinus thrombosis result in
Brain damage which is shown through headache and epileptic seizures, focal motor deficit and deterioration of consciousness
311
What forms the ventricles in the brain
The brain develops from a hollow neutral tube which remains hollow, the central spaces become the ventricles
312
What are ventricles important for
The formation of cerebrospinal fluid
313
Where is the largest aggregation of choroid plexus found
Found in the lateral ventricle
314
Where is the majority of the cerebrospinal fluid produced
The majority of the cerebrospinal fluid is produced in the lateral ventricle
315
How does cerebrospinal fluid pass from the ventricles
Cerebrospinal fluid passes from the ventricles via the intraventricular foramen and into the 3rd ventricle
316
From the 3rd ventricle where does the cerebrospinal fluid flow
From the 3rd ventricle the cerebrospinal fluid passes backwards through the cerebral aqueduct into the 4th ventricle
317
How does the 4th ventricle communicate with the subarachnoid space
The 4th ventricle communicates with the subarachnoid space via the median foramen of magendie and the lateral foramen of luschka
318
How does the cerebrospinal fluid pass into the subarachnoid space around the brain and spinal cord
The cerebrospinal fluid passes through the median foramen of magendie and lateral foramen of luschka
319
What is the choroid plexus
The choroid plexus is an invagination of vessels into the ventricles which produces a vascular fold of pia mater covered by an epithelium derived from the ependymal lining of the ventricle
320
What prevents the passage of fluid from the extra cellular space of the choroid plexus
Tight junctions
321
How can fluid from the extracellular space of the choroid plexus into the ventricles
Via the choroidal cells
322
With fluid only been able to pass from the extracellular space into the ventricles via choroidal cells what does this enable
This enables high control over the volume and composition of the cerebrospinal fluid
323
What does the cerebrospinal fluid brain barrier constitute of
The ependyma
324
How does the cerebrospinal fluid become re absorbed into the venous drainage of the brain
Resorption of cerebrospinal fluid into the venous drainage of the brain occurs via tufts of the arachnoid mater
325
What are the tufts of the arachnoid mater that aid cerebrospinal resorption called
They are called arachnoid villi
326
How are the arachnoid granulations formed
Arachnoid granulations are formed via the calcification of the arachnoid villi
327
Why do arachnoid villi calcify
They calcify due to advancing age
328
What does the presence of arachnoid villi cause
The arachnoid villi tend to cause the bone to be resorbed along the internal surface of the cranial vault near the midline which causes small pit like structures
329
What is the ventricle aperture of the magendie foramen
The magendie foramen is the medial aperture
330
What is the ventricle aperture of the luschka foramen
The luschka foramen is the lateral aperture
331
What does the anterior cranial fossa contain
The frontal lobe of the brain
332
What is the ethmoid bone composed of
Cribriform plates and the crista galli
333
What does the middle cranial fossa contain
Temporal, parietal and occipital lobes of the brain
334
What does the posterior cranial fossa contain
The cerebellum, pons and medulla oblongata
335
What runs through the carotid foramen
The internal carotid artery
336
What runs through the jugular foramen
Internal jugular vein and cranial nerves IX, X, XI
337
What runs through the foramen magnum
Vertebral arteries
Anterior and posterior spinal arteries
Spinal cord
338
What runs through the internal acoustic meatus
Cranial nerve VII- facial nerve
Cranial nerve VIII- vestibulocochlear nerve
339
What runs through the ethmoid foramen
Cranial nerve I- Olfactory nerve
340
What runs through the optic canal
Cranial nerve II- optic nerve
341
What runs through the orbital fissure
Cranial nerve III- Oculomotor nerve
Cranial nerve IV- trochlea nerve
Cranial nerve VI- abductees nerve
Cranial nerve V 1- trigeminal ophthalmic
342
What runs through the foramen rotundum
Cranial nerve V 2- trigeminal maxillary nerve
343
What runs through the foramen ovale
Cranial nerve V 3- trigeminal mandibular
344
What runs through the hypoglossal canal
Cranial nerve XII- hypoglossal
345
What can cause raised inter-cranial pressure
Space occupying lesions such as tumours, haematoma’s or abscesses
Idiopathic intracranial hypertension
346
What are examples of signs and symptoms caused by raised intracranial pressure
Headaches
Nausea
Visual disturbances
Altered consciousness
347
What is the orbit
The orbit is the bony structure that protects the eyeball and associated structures
348
What is the supra-orbital nerve a branch of
A branch of the frontal nerve
349
What is the supratrochlear nerve a branch of
The frontal nerve
350
Where does the frontal nerve run
Centrally
351
What is the lacrimal nerve a branch of
The frontal nerve
352
Where does the lacrimal nerve run
Laterally in the orbit
353
Where does the levator palpebrae superioris originate
It originates at the posterior of the orbit at the common tendinous ring
354
Where does the levator palpebrae superioris insert
Into the upper eyelid
355
Where is the lacrimal gland located
Just inside the lateral margin of the orbit adjacent to the lateral margin of levator palpebrae superioris
356
Where does the superior rectus originate
It originates in the deep part of the orbit at the common tendinous ring
357
Where does the superior rectus run
It runs over the top of the eyeball
358
Where does the superior rectus insert
It inserts anterior to the equator to the eyeball just behind the conjunctival sac
359
Where is the trochlear nerve located
At the medial edge of the superior orbital fissure
360
Where does the trochlear nerve run
It passed froward from the cavernous sinus and terminates on the superior oblique muscle
361
Where does the lateral rectus muscle run
It runs along the length of the lateral walls of the orbit on a deeper plane of the larcrimal gland
362
Where is the oculomotor nerve located
Deep to the levator palpebrae superioris
363
Where does the superior oblique originate
It originates at the posterior of the orbit
364
Where does the superior oblique run
It runs forward to pass through the trochlear
365
Where does the superior oblique insert
It inserts onto the posterior part of the eyeball
366
Where does the medial rectus muscle run
The medial rectus muscle runs along the length of the medial aspect of the orbit on a deeper plane than the superior oblique muscle
367
What is the ophthalmic artery a branch of
Internal carotid artery
368
Where does the ophthalmic artery run
The ophthalmic artery runs lateral to medial over the optic nerve
369
Where does the central artery of the retina pass into
The central artery of the retina passes into the optic nerve
370
What does the nasociliary nerve attach to
Attached to the ciliary ganglion
371
What lies above the inferior rectus muscle
Subarachnoid space
372
Where is the oculomotor nerve located
The oculomotor nerve is located to both the medial and inferior rectus muscles
373
Where is the abducens nerve located
The abducens nerve is located to the lateral rectus muscle
374
Where does the inferior oblique muscle run
The inferior oblique muscle runs from the medial aspect of the orbit posterolaterally
375
Where does the inferior oblique muscle insert
The inferior oblique muscle inserts onto the sclera behind the equator of the eyeball
376
What are the lacrimal puncti
Small medial holes in the upper and lower eyelids
377
Where is the lacrimal sac located
Posterior to the medial palpebral ligaments
378
Where does the nasolacrimal duct drain from and to
The nasolacrimal duct drains from the inferior part of the lacrimal sac to the nasal cavity
379
Where does parasympathetic outflow from the CNS run via
Via the oculomotor, facial, glossopharyngeal and vagus nerves and the sacral spinal segments 2, 3 and 4
380
Where do parasympathetic fibres from the oculomotor nerve originate from
They originate in the Edinger-Westphalia nucleus in the midbrain
381
Where do parasympathetic fibres travel into from the Edinger-westphal nucleus
They travel into the branch to the inferior oblique muscle
382
When the parasympathetic fibres leave the inferior oblique muscle where does it enter
It enters a small ganglion, the ciliary ganglion
383
What do fibres that leave the ciliary ganglion innervate
Innervate the ciliary muscle and sphincter pupillae
384
Where do parasympathetic fibres of the facial nerve leave and synapse
The parasympathetic fibres of the facial nerve leave the facial nerve in the middle ear and synapse in the ganglion in the pterygopalatine fossa which supply’s the lacrimal gland
385
Where does sympathetic outflow from the CNS occur and where do they pass into
Through the spinal segments T1 to L2 and pass into the sympathetic trunk
386
Where do sympathetic fibres to the orbit arise from
They arise from T1
387
From T1 where do the sympathetic fibres for the orbit run
Once in the sympathetic trunk they pass upwards through the Stellate ganglion in the base of the skull
388
Where do sympathetic fibres to the orbit leave the sympathetic trunk
They leave the superior cervical ganglion
389
What do the sympathetic fibres innervate
The dilator pupillae muscle and blood vessels
390
What is the medial rectus innervated by
The oculomotor nerve
391
What way does the medial rectus move the eye
This moves the eye inwards towards the nose- adduction
392
What is the lateral rectus innervated by
Abducens nerve
393
What way does the lateral rectus move the eye
Moves the eye outwards away from the nose- abduction
394
What is the superior rectus innervated by
Oculomotor nerve
395
What way does the superior rectus move the eye
Primarily it moves the eye upwards- elevation
Secondary it rotates the top of the eye towards the nose- intorsion
Tertiarly it moves the eye inwards- adduction
396
What is the inferior rectus innervated by
Oculomotor nerve
397
What way does the inferior rectus move the eye
Primarily it moves the eye downwards- depression
Secondarily it rotates the top of the eye away from the nose- extortion
Tertiary it moves the eye inward- abduction
398
What is the superior oblique innervated by
Trochlear nerve
399
What way does the superior oblique move the eye
Primarily rotates the top of the eye towards the nose
Secondarily moves the eye downwards- depression
Tertiarily moves the eye outwards- abduction
400
What is the inferior oblique innervated by
Oculomotor nerve
401
How does the inferior oblique move the eye
Primarily it rotates the type of the eye away from the nose- extortion
Secondarily it moves the eye upwards- elevation
Tertiarly it moves the eye outwards- abduction
402
What is the retina
The posterior of the eyeball
403
Where can the optic disc be found
The optic disc lies at the level of which the optic nerve attaches
404
Where do the retinal arteries and veins come from
The optic disc
405
Where can the macula lutea be found
Lateral to the optic disc
406
Where is the lens found
In the anterior part of the eye
407
Where does the ciliary processes come from
The lens
408
Where is the iris found
The iris is within the anterior chamber
409
When can the iris be visible
After the lens becomes detached
410
What causes jugular Foramen syndrome
The compression of multiple lower cranial nerves- the glossopharyngeal, vagus and accessory
411
What are the signs and symptoms of jugular foramen syndrome
Dysphonia
Loss of gag reflex
Unilateral wasting of sternocleidomastoid and trapezius muscle
412
What causes foramen magnum syndrome
Compression of the spinal cord, lower brain stem or part of the cerebellum
413
What are signs and symptoms of foramen magnum syndrome
Pain in head, neck, limbs and trunk made worse be straining
Cerebellar symptoms eg-vertigo
Cardiorespiratory failure
Death
414
What is Arnold-chiari malformation
This is a congenital malformation, where there is displacement of the cerebellar tonsils down through the foramen magnum which can block the flow of cerebrospinal fluid causing hydrocephalus
415
Signs and symptoms of Arnold-Chiari malformation
Headaches
Fatigue
Difficulty swallowing
Dizziness
416
Where is the petrous temporal bone located
In the floor of the middle cranial fossa
417
What is the greater petrosal nerve a branch of
It is the parasympathetic branch of the facial nerve
418
Where does the greater petrosal nerve run
It runs through the petrous temporal bone and passes anteromedially
419
Where can the tympanic tympani be located
It lies lateral and posterior to the greater petrosal nerve
420
What are the ear ossicles
Stapes, malleus and incus
421
What does the tympanic membrane attach and articulate with
The tympanic membrane attaches to the malleus and articulates with the incus
422
What is the chorda tympani nerve a branch of
It is a branch of the facial nerve
423
What nerve crosses the tympani membrane
Chords tympani nerve
424
What does the internal acoustic meatus do
It transmits the facial and vestibulocochlear nerves
425
What is a acoustic neuroma
A benign tumour of the myelin sheath of the vestibulocochlear nerve
426
What are signs and symptoms of a acoustic neuroma
Unilateral deafness
Dizziness
Tinnitus
427
What is the midbrain divided into
The dorsal tectum and the ventral tegmentum
428
Where is the pons located
The pons is located in the middle of the midbrain and the medulla
429
What is the medulla oblongata a continuation of
The medulla oblongata is a continuation of the spinal cord within the skull
430
Where does the medulla oblongata begin
At the foramen magnum
431
Why is the medulla oblongata restricted
It is limited above by the caudal border of the pons and the bulbopontine sulcus
432
What is the included in the dorsal tectum
Anything that lies dorsal to the aqueduct of the midbrain and the 4th ventricle
433
What is included in the ventral tegmentum
Anything which lies ventral to the aqueduct of the midbrain and 4th ventricle
434
What are the crus cerebri
2 columns of the descending fibres eg-corticospinal and corticobulbar
435
Where is the bulbpontine sulcus located
A transverse groove which is located at the caudal border of the pons
436
What runs in the basilar sulcus
The basilar artery
437
Where are the middle cerebellar peduncles found
Lateral extensions of the neural tissue from the pons to the cerebellum
438
Where is the anterior median fissure
A partial division of the medulla in the ventral midline
439
What is a pyramid
A pyramid is an elongated eminence marking the position of underlying fibres passing from the cerebral hemisphere to the cord
440
What is the decussation of the pyramids
This is a diagonally oriented bundles of fibres crossing the fissure via which 80% of the corticospinal fibres cross to enter the lateral white column of the spinal cord
441
Where is the olive located
The olive is located lateral to the ventral lateral sulcus
442
What is the olive
The olive is a eminence causes by the presence of underlying inferior olivary nucleus
443
What is the function of the olive
Control of movement
444
What is the inferior cerebellar peduncle
The inferior cerebellar peduncle forms the posterolateral margins of the medulla, a thick bundle of white matter passing into the cerebellum
445
What is the tectum
This is the midbrain dorsal to the aqueduct
446
What is the tectum composed of
Colliculi
447
What is the tegmentum
The midbrain ventral to the aqueduct
448
What is the tegmentum made up of
Nerve fibres entering and leaving the cerebral hemispheres and nerve nuclei
449
What is the superior colliculi part of and what is its function
Part of the visual system and concerned with visual reflexes
450
What is the inferior colliculi part of and what is its function
Part of the auditory system and concerned with the reflex of looking towards a loud noise
451
What is the superior cerebellar peduncle
A fibre bundle passing from the cerebellum to the midline
452
What is the pineal gland
This is an endocrine gland that synthesises melatonin which modulates sleep pattern in both circadian and seasonal cycles
453
What is the inferior brachium
This conveys auditory information from the medial geniculate nucleus to the inferior colliculi
454
What is the superior brachium
Conveys visual information back to the lateral geniculate nucleus to the superior colliculi
455
What does the tegmentum of the pons contain
The nuclei of the abducent, facial and trigeminal cranial nerves
456
What does the posterior median sulcus mark
The midline of the medulla oblongata
457
What is the gracile tubercle
It is a round swelling on either side of the midline which overlies the gracile fasciculus
458
What is the function of the gracile fasciculus
This carries fine touch, vibrations, 2-point discrimination and proprioception from the lower limb
459
What is the cuneate tubercle
It is a swelling lateral to the gracile tubercle overlying the cuneate fasciculus
460
What is the function of the cuneate fasciculus
This carries fine touch, vibrations, 2-point discrimination and proprioception from the upper limb
461
What is the floor of the 4th ventricle
The rhomboid fossa
462
What does the tegmentum of the medulla oblongata contain
The glossopharyngeal, vagus,accessory and hypoglossal
463
What is Bell’s palsy
Acute unilateral inflammation of the facial nerve
464
Is Bell’s palsy is caused by herpes zoster what may appear
A vesicular rash in the external auditory canal and on the oropharynx
465
Signs and symptoms of Bell’s palsy
Pain behind the ear
Paralysis of facial muscles
Unable to close one eye
Loss of taste on anterior 2/3 of tongue
466
What is bulbar palsy
Impairment of the functions of the cranial nerves that arise from the medulla
467
What are the cranial nerves that arise from the medulla
Glossopharyngeal
Vagus
Accessory
Hypoglossal
468
What are some signs and symptoms you can get with bulbar palsy
Dysphagia
Dysphonia
Absent gag reflex
469
What can cause bulbar palsy
Motor neurone disease and guillian barre syndrome
470
What is pseudobulbar palsy
You would present with Similar symptoms to bulbar palsy but the lesion is in the upper motor neurones caused by stroke
471
What is central pontine myelinolysis
Destruction of the myelin in the pons
472
What are signs or symptoms of central pontine myelinolysis
Confusion
Balance problems
Slurred speech
473
When does central pontine myelinolysis occur
When low sodium levels are corrected too quickly
474
What is the largest part of the hindbrain
Cerebellum
475
What is the cerebellum involved with
Coordination of movement and balance
476
What is the cerebellum comprised of
2 hemispheres
477
what joins the 2 cerebellum hemispheres
The 2 hemispheres of the cerebellum are joined by the vermis in the midline
478
Where does the cerebral aqueduct run
Through the midbrain
479
What does the cerebral aqueduct do
Interconnects the IIIrd and IVth ventricle
480
What is the red nucleus
A circular mass of grey matter
481
Where is the red nucleus located
Ventral-lateral to the cerebral aqueduct
482
What is the substantia nigra
A black band of nerve cells overlying the crus cerebri
483
Where is the substantia nigra located
Ventro-lateral to the red nucleus on each side
484
What is the vermis
This is a worm like ridge of tissue that connects either side of the cerebellum hemispheres
485
What is the horizontal fissure
The horizontal fissure marks the lateral and posterior margins of the hemisphere
486
What converges on the horizontal fissure
The fissures and folia of the superior surface curve from the postero-medial to antero-lateral onto the horizontal fissure
487
What borders the anterior border
The primary fissure
488
What borders the posterior lobe
Bordered by the primary fissure anteriorly and the horizontal fissure posteriorly
489
What does the primary fissure mark the division of
The primary fissure marks the division between the anterior and posterior lobes of each cerebellar hemisphere
490
What is the tonsil
The tonsil is a prominent rounded swelling of the cerebellar cortex anteriorly on either side of the vermis
491
Where is the flocculus located
Ovid in shape with a crinkled edge which lies immediately posterior to the lateral foramen of the IVth ventricle on each side partly covered by choroid plexus. It lies immediately caudal to the entry point of the vestibulocochlear nerve and is crossed anteriorly by the emerging vagus nerve and the hypoglossal nerves
492
What is the nodule
It is continuous with the flocculus via the peduncle of white matter
493
What makes up the flocculo-nodular lobe
The flocculus and the nodule together make up this lobe
494
What is the flocculo-nodular lobe involved in
Primarily involved with vestibular information
495
What does the corticopontocerebellar do
Information from the primary motor cortex from the motor plan, the same information goes to the spine
496
What does the vestibulocerebellar tract do
Carries vestibular impulses from the labyrinths directly and via the vestibular nucleus
497
What does the spinocerebellar tracts do
Carries sensory input for balance and position
498
What is the debate nucleus
The largest and most lateral of the deep cerebellar nuclei with major fibre bundles passing into the superior cerebellar peduncle
499
What connects the cerebellum to the medulla, pons and midbrain
By the inferior, middle, superior cerebellar peduncles
500
What is the rhomboid fossa
Diamond shaped floor of the IVth ventricle
501
What limits the rhomboid fossa laterally and posteriorly
It is limited by the cerebellar peduncles laterally
It is limited by the gracile and cuneate tubercles posteriorly
502
What do the gracile tubercles do
They carry touch, vibration, two-point discrimination and proprioception from the lower limbs
503
What do the cuneate tubercles do
They carry touch, vibration, two-point discrimination and proprioception from the upper limb
504
What does the median sulcus do
It divides the rhomboid fossa into triangular left and right halves
505
What is the facial colliculus
A rounded swelling caused by the fibres of the facial nerve in the substance of the pons curving around the nucleus of thr abducens nerve at the superior fovea
506
Where is the medullary striae found
The medullary striae is found aberrant ponto-cerebellar fibres passing from the pons to the cerebellum
507
What does the medullary striae do
They divide the floor of the ventricle into rostral pontine half and the caudal medullary half
508
Where is the locus coeruleus located
This is the blueish grey pigmented noradrenergic cells under the ependyma at the rostral half of the sulcus limitans
509
What is the hypoglossal trig one
It is the medial triangular are which overlies the hypoglossal nerve nucleus
510
What is the vagal trigone
The intermediate triangular area which overlies the vagus nerve nucleus
511
What is the vestibular trigone
Lateral triangular area which overlies the vestibularchoclear nerve nucleus
512
What is the obex
The inferior apex of the rhomboid fossa
513
What is the area postrema
A small tongue shaped area immediately Rostropovich-lateral to the obex
514
What is the function of the area postrema
This is the common site of nausea control, as it is a chemoreceptive trigger zone for the emetic response and lies outside the blood brain barrier
515
What is the IIIrd ventricle
A narrow slit cavity lying in the midline between the two halves of the diencephalon
516
What borders the IIIrd ventricle anteriorly
Lamina terminalis
517
What borders the IIIrd ventricle superior
Tele choroidea
518
What borders the IIIrd ventricle inferiorly
Optic chiasma
Pituitary stalk
Mammillary bodies
Tegmentum of the midbrain
519
Where is the interventricular foramen located
It is located immediately behind the upper end of the column of the fornix
520
What is the function of the interventricular foramen
Permits Cerebrospinal fluid flow from the lateral ventricles to the IIIrd ventricle.
This narrow opening is the only communication between the lateral ventricles and the rest of the ventricular system
521
What is the intraventricular foramen filled with
Choroid plexus
522
What is the paracentral lobule
This is a U shaped gyrus surrounding the medial extension of the central sulcus
523
What does the paracentral sulcus contain
This contains the representations of the lower limb within the primary motor and somatic sensory areas of the cortex
524
Where is the motor cortex found
In the pre-central gyrus
525
Where is the somatic sensory cortex located
It is found in the post-central gyrus
526
Where is the cingulate sulcus located
It seperates the the cingulate gyrus from the rest of the hemisphere
527
Where does the cingulate sulcus run
Above the corpus callosum
528
Where is the parieto-occipital sulcus located
Lies on the medial surface of the hemisphere where it forms a y-shaped arrangement with the calcarine sulcus
529
Where does the calcarine sulcus run
It runs posterior towards the occipital pole
530
What lies in the wall of the calcarine sulcus
The primary visual cortex
531
What is the striae of Genari
A white band in the primary visual cortex
532
What is the corpus callosum
A broad arched band of white matter which connects the 2 hemispheres of the brain
533
What is the genu
The anterior curved end of the corpus callosum
534
What is the rostrum
It is the downward connection from the genu of the corpus callosum
535
What is the body of the corpus callosum
The body of the corpus callosum is the main curve of the band of white matter
536
What is the splenium of the corpus callosum
The rounded posterior end of the corpus callosum
537
What is the fornix
A bundle white matter underneath the corpus callosum
538
What is the function of the fornix
It connects the hippocampus with the diencephalon and precommissural septum
539
What is the columns of the fornix
Anterior and posterior extensions of the fornix
540
Where do the anterior projections of the fornix go to
The anterior extensions go down to the mammillary bodies
541
What is the anterior commissure
A thick bundle of white matter crossing the midline horizontally between the lamina terminalis and the fornix
542
What is the septum pellucidum
Two thin vertical sheets made primarily of glia with a few white fibres, very sparse grey matter and a covering of ependyma at the anterior inferior border of the corpus callosum from the fornices
543
What is the lamina terminalis
A thin sheet of ependyma and pia which extends downwards from the rostrum of the callosum and fornix to the anterior wall of the IIIrd ventricle
544
Where is the thalamus
Dorsal part of the diencephalon
545
What is the function of the thalamus
The thalamus is a major sub cortical relay for information ascending into the cerebral cortex
546
What is a interthalmic adhesion
A flattered disc joining the thalami of each side behind the interventricular foramen
547
What is the hypothalamic groove
A shallow groove on the lateral wall of the IIIrd ventricle which divides the diencephalon into dorsal and ventral parts
548
What is the function of the medial geniculate nucleus
It relays information from the midbrain to the auditory cortex and passes some fibres via the inferior brachium to the inferior colliculi
549
What is the function of the lateral geniculate nucleus
It relays visual information from the optic nerve to both visual cortexes via optic radiation’s and the superior colliculi via the superior brachium
550
Where is the hypothalamus located
It is the ventral part of the diencephalon
551
What is the function of the hypothalamus
It is an important centre which contributes to the body’s homeostasis and to autonomic nervous and neuroendocrine system control
552
What is the subthalamus
Location
Function
Ventral part of the diencephalon below the thalamus and lateral to the hypothalamus
Closely associated with the basal ganglia
553
What is the preoptic area
Location
Function
It is found adjacent to the lamina terminalis and in front of the optic chiasma
It’s function should be considered the same as the hypothalamus
554
What are the 3 different fibres found in different areas of the cortex
Association fibres
Commissural fibres
Projection fibres
555
What are association fibres
They link cortical regions within one cerebral hemisphere
556
What are commissural fibres
Link similar functional areas of the two hemispheres like the corpus callosum
557
What are projection fibres
They link the cortex with subcortical structures such as the thalamus and the spinal cord via the internal capsule and corona radiata
558
What are the functions of the commissural fibres
The commissural fibres between the areas of the cortex on each side containing representations of either one half of the body or one hemisphere-visual field concentrated also most entirely in the midline
Many higher functions are all contained within one hemisphere
559
What happens if the corpus callosum is damaged
If the corpus callosum is completely divided the 2 cerebral hemispheres wont be able to communicate and so will function autonomously
560
What is function of the limbic system
The limbic system acts as an interface between the internal environment of the individual and then external environment
561
What is the limbic system essential for
It is essential for adaptive behaviour, emotional responsiveness and the ability to learn new responses based on pervious experiences from memory
562
What is related to the limbic system
The olfactory system
563
What are the 2 major functional roles of the limbic system
Role in learning
Role in regulation and translation of our emotional state into appropriate behaviour
564
Where are the main parts of the limbic system located
The main parts of the limbic system are located on the edge or limbus of the hemisphere
565
How are the main parts of the mimic system connected
They are connected via the papez circuit
566
What does the limbic system include
The cingulate gyrus
The hippocampal formation
Parahippocampal gyrus
Anterior perforated substance
The septal nuclei
The uncus
The amygdala
But can include the diencephalic structures associated with the limbic cortex- structures which are on either side of the third ventricle including the thalamus, the hypothalamus, the epithalamus and the sub thalamus
567
Where can the cingulate gyrus located
The cingulate gyrus lies immediately dorsal and parallel to the corpus callosum
568
Where can the parahippocampal gyrus be found
It is found in continuity with the cingulate gyrus around the splenium of the corpus callosum
Found part of the temporal lobe
569
What is the uncus
Where is it located
What is its function
The uncus is a hook shaped region of the cortex at the anterior end of the temporal lobe
The uncus plays a role in olfaction, emotions and memory
570
Where is the olfactory tract located
The olfactory tract is located on the orbitofrontal surface of the brain
571
What runs in the olfactory tract
Cranial nerve I
572
Where can olfactory striae be located
Olfactory striae can be found in the olfactory tract along the anterior border of the anterior perforated substance, the fibres run medially and laterally
573
Where do the lateral striae run to
The uncus
574
Where is the column of the fornix loacted
The column of the fornix is found passing behind the anterior commissure
575
What are association fibres
They are axons interconnecting different areas of the cerebral cortex of one hemisphere
576
What are short association fibres for
Short association fibres are for the connecting the instance the cortex of neighbouring gyri
577
What are long association fibres for
They pass between areas in different lobes of one hemisphere
578
What is the largest bundle of association fibres
The superior longitudinal fasciculus
579
Where is the corona radiate located
The corona radiate is located deep to the Cingulum bundle
580
What is the function of the corona radiata
This structure carries fibres between the cortex and subcortical structures
581
What are the fibres of the corona radiata continuous with
They are continuous with the internal capsule
582
Where is the anterior horn of the lateral ventricle located
It curves downwards into the frontal lob from the interventricular foramen
583
What are the roof and anterior wall of the anterior horn of the lateral ventricle made up of
The roof and the anterior wall of the anterior horn of the lateral ventricle are formed by the body and genu of the corpus callosum
584
What is the caudate nucleus made up of
It has a head, body and tail
585
What does the caudate nucleus form
It forms a large bulge into the inferno-lateral aspect of the anterior horn of the ventricle
586
Where is the body of the lateral ventricle located
The body of the lateral ventricle is roofed over the main part of the corpus callosum
587
What is the stria terminalis
The stria terminalis is a slender bundle of white fibres which accompany the curve of the caudate nucleus around into the temporal horn of the ventricle and connects the amygdala with the septum and hypothalamus
588
Where is the lateral horn of the lateral ventricle found
The tail of the caudate nucleus and the stria terminalis both follow the inner curve of the ventricle and become continuous with the amygdaloid body at the tip of the inferior horn
589
What is the shape of the amygdala
Shaped like an almond
590
Where is the amygdala located
The amygdala overlies the medial side of the tip of the inferior horn deep to the uncus
591
What is the amygdala continuous with medially and posteriorly
The amygdala is continuous medially with the cortex of the temporal lobe
The amygdala is continuous posteriorly with the tail of the caudate nucleus
592
What is hippocampus
The hippocampus is a complex infolding of the cortex which forms a convex curve about 5cm long which lies medially in the floor of the inferior horn of the ventricle
593
What is the pes hippocampi
The pes hippocampi is the anterior view of the hippocampus which has 2 or 3 shallow grooves giving a paw like appearance
594
What is fimbria
The fimbria are efferent fibres from the hippocampus heading to the fornix
595
Where is the posterior horn of the lateral ventricle located
The posterior horn of the lateral ventricle is seen as a variable extension of the lateral ventricle into the occipital lobe
596
What could lesions in the limbic system cause
Lesions in the limbic system would depend on the location of the lesion to what it could cause. Any lesion could cause anterograde amnesia, generation of emotion and emotional response in the absence of external stimulation, production of inappropriate emotional responses to particular stimuli, inability to detect the emotional state of others and inability to regulate our own emotional response
597
What causes hydrocephalus
Blockage of cerebrospinal fluid in the ventricles or subarachnoid space
598
What could cause blockage for cerebrospinal fluid in the ventricles or sub-arachnoid space
Blockage in the ventricles can be caused by tumours
Blockage in the sub-arachnoid space can be caused by adhesions following meningitis or trauma
599
How can hydrocephalus be resolved
A shunt can be inserted to relieve the pressure
600
How does a shunt work
A shunt is connected to the ventricular system which can drain the cerebrospinal fluid to the peritoneum or jugular vein
601
What are signs and symptoms of hydrocephalus
Raised inter-cranial pressure
Headache
Unsteadiness
Mental impairment
602
What is the extreme capsule
White matter
603
What is the claustrum
The claustrum forms part of the basal ganglia
604
What is the function of the claustrum
The claustrum receives and projects to the cerebral cortex in a topographically manner which have cells which can respond to visual, auditory and sensory stimuli
605
What is the external capsule
White matter which seperates the claustrum from the putamen
606
What is the lentiform nucleus comprised of
The laterally placed putamen and the lateral segment of the globus pallidus
607
What is the lateral segment of the globus pallidus
Grey matter
608
What is the medial medullary lamina
White matter found between the lateral and medial segments of the globus pallidus
609
What is the medial segment of the globus pallidus
Grey matter
610
What is the internal capsule
The internal capsule is the convergence and concentration of white matter projection fibres which carry all motor and sensory fibres to and from the cortex
611
What is the corona radiata
White matter fibres radiating from the internal capsule deep to the lentiform nucleus
612
What is the forceps major
The posterior curve of the corpus callosum fibres which run into the parietal and occipital lobes which forms about 2/3rds of a circle with the opposite side
613
What is the forceps minor
The forceps minor is the anterior curve of the corpus callosum fibres running into the fromntal lobe which forms 2/3rds of a circle on the opposite side
614
What causes Parkinson’s disease
Degeneration of dopaminergic neurons of the substantia nigra which leads to the depletion of striatal dopamine levels
615
What is the cause of Parkinson’s disease and how can it be treated
Cause is usually unknown but some genetic input
Treatment with levodopa can minimise symptoms for years
616
Signs and symptoms of Parkinson’s disease
Cog-wheel rigidity
Pill-rolling tremor at rest
Shuffling festinant gait
Bradykinesia
Loss of facial expression
617
What type of disease is Huntington’s chorea
An autosomal dominant disease which is inherited
618
Signs and symptoms of Huntington’s chorea
Chorea
Personality changes
Depression and progressive dementia
619
What is lacunar stroke
It is an occlusion of a deep perforating artery
620
What are risk factors of a lacunar stroke
Hypertension
Smoking
Diabetes mellitus
621
What can a stroke affecting the internal capsule cause
Hemiparesis which can typically affecting half the face, one leg and arm
Ataxia hemiparesis
Mixed sensorimotor stoke if the thalamus is affected
622
What number cranial nerve is cranial nerve I
Olfactory
623
What is the function of cranial nerve I
Smell
624
What cranial nerve is number II
Optic
625
What is the function of the optic cranial nerve
Visual/sight
626
What is the name of cranial nerve III
Oculomotor nerve
627
What is the function of the oculomotor cranial nerve
Eye movement
Eye lid opening
Pupil constriction
628
What is the IV cranial nerve
Trochlear nerve
629
What is the function of the trochlear nerve
Moves the superior oblique
630
What is the name of cranial nerve V
Trigeminal
631
The trigeminal splits in to 3 what are the 3 branches called
V1- ophthalmic
V2- maxillary
V3- mandibular
632
What is the name of cranial nerve VI
Abducens nerve
633
What is the function of the abducens nerve
The abducens nerve moves the lateral rectus
634
What is the name of cranial nerve VII
Facial nerve
635
What is the name of cranial nerve VIII
Vestibularcochlear nerve
636
What is the name of cranial nerve IX
Glossopharyngeal nerve
637
What is the name of cranial nerve X
Vagus nerve
638
What is the name of cranial nerve XI
Accessory nerve
639
What is the name of cranial nerve VII
Hypoglossal nerve
640
What type of fibres does cranial nerve I carry
Sensory
641
What fibres do cranial nerve II carry
Sensory
642
What fibres do cranial nerve III carry
Motor
643
What fibres do cranial nerve IV carry
Motor
644
What fibres do cranial nerve V carry
Both motor and sensory
645
What fibres do cranial nerve VI carry
Motor
646
What fibres do cranial nerve VII carry
Both motor and sensory
647
What fibres do cranial nerve VIII carry
Sensory
648
What fibres do cranial nerve IX carry
Both motor and sensory
649
What fibres do cranial nerve X carry
Both sensory and motor
650
What fibres do cranial nerve XI carry
Motor
651
What fibres do cranial nerve XII carry
Motor
652
What does the vertebral column consist of
7 cervical vertebrae
12 thoracic vertebrae
5 lumbar vertebrae
The sacrum
653
What forms the sacrum
5 fused vertebrae and the coccyx
654
What is does the coccyx consist of
The coccyx consist of 4 or more rudimentary vertebrae
655
What is the function of the vertebral column
The vertebral column transmits the body weight on to the lower limbs through the sacroiliac joints
656
What is found in the vertebral canal
The spinal cord and its coverings along with spinal nerves
657
What is an individual vertebrae made up of
The body
The pedicle
The lamina
The spinous processes
The transverse processes
The superior and inferior articular processes
658
What is important about the 7th cervical vertebrae and what is it known as
It is the upper most spinous process that is palpable
It is known as the vertebra prominent
659
Why is the 7th cervical vertebrae known as the vertebra prominent
It is known as the vertebra prominent as it has a long and non-bifid spine
660
What is the highest point of the iliac crest in line with on the vertebral column
The iliac crest is in line with the interval between L3 and L4
661
What shape is the vertebral column
Sinusoidal shape
662
When does the sinuosidal shape of the vertebral column develop
After birth
663
What shape is the vertebral column in a foetus
C-shaped
664
When is a secondary curvature developed in a baby
The cervical region develops a curvature when the child begins to hold up there head
665
When does the lumbar curvature form in a baby
The lumbar curvature forms when the child starts to bear weight on their legs
666
What are the movements of the vertebral column
Forward flexion 40 degrees
Extension 15 degrees
Lateral flexion 30 degrees
Rotation 40 degrees
667
Where is the rotation of the vertebral column at the maximum
Thoracic region
668
Where is rotation of the vertebral column rotation limited
The lumbar region
669
Where is flexion and extension most limited in the vertebral column and why
Thoracic region due to the rib cage
670
What are intervertebral discs
They are strong fibrocartilaginous structures that can withstand compression forces but are flexible enough to allow movement between the vertebrae
671
What are the 2 parts that make up an intervertebral disc
A nucleus pulposus which is surrounded by an annulus fibrosis
672
What is the nucleus pulposus
The nucleus pulposus is a well hydrated gel - proteoglycan, collagen and cartilage cells
673
What is the annulus fibrosis
The annulus fibrosis is made of 10-12 concentric layers of collagen whose oblique arrangement alters in successive layers
674
Peripherally what is the annulus fibrosis attached to
The vertebral bodies as well to the posterior longitudinal ligament
675
What can herniation of the intervertebral disc cause
This can cause narrowing of the intervertebral foramen and compression of the nerve root
676
What is more common in herniation of the lumbar region
Herniation in the lumbar region is different as the annulus fibrosis of the intervertebral disc no longer contains the nucleus pulposus and so it begins to bulge into the spinal canal or intervertebral foramina
677
What prevents posterior herniation of an intervertebral disc
A posterior herniation is often prevented by the firm attachment of the disc to the posterior of the longitudinal ligament
678
What type of herniation is more common
Intervertebral foramina herniation
679
What can arthritis of the facet joints and/or the bony irregularities in the pedicle or vertebral body cause
Narrowing of the intervertebral foramen and nerve root compression
680
What is radiculopathy
Nerve root pathology
681
What is radiculopathy caused by
It is mot commonly caused by compression due to a prolapsed intervertebral disc
682
Where is radiculopathy most commonly seen
L5 and S1 in the lumbar region and C6/7 in the cervical region
683
What is sciatica
Sciatica is caused by compression or irritation of the sciatic nerve at L5
684
What are signs and symptoms of sciatica
Pain radiating down the buttock into the leg and down to the calf
Weakness in dorsiflexion foot drop
Abnormal gait
685
What is the epidural space
The epidural space os a space between the vertebrae and the dura mater of the spinal cord
686
What does the epidural space contain
The space contains small arteries which supply the spinal cord, vertebral plexuses, veins in the plexuses known as Bateson veins contain no valves and communicate freely with the intercostal veins and pelvic veins including veins draining the prostate
687
What is cauda equina syndrome
Compression of the nerve roots below the level of spinal cord termination which is L1-S5
688
What is cauda equina sydrome most commonly caused by
Most commonly it is caused by disc prolapse at L4/5 or L5/S1
689
What are common signs and symptoms of cauda equina syndrome
Low back pain
Perineal paraesthesia
Decreased anal tone
Bladder dysfunction
Faecal incontinence
Sciatica
Lower extremity motor and sensory loss
Sexual dysfunction
690
What is a spinal cord segment
A spinal cord segment is an area on the spinal cord from which a pair of spinal nerves are given off
691
What does the dorsal root of the spinal nerve carry
Sensory fibres
692
What does the dorsal root ganglion house
The dorsal root ganglion houses the cells of origin of the dorsal root fibres
693
What does the ventral root of the spinal nerve carry
Motor fibres
694
Where does the ventral root emerge on the spinal cord
The ventral root emerges on the anterolateral aspect of the cord on either side
695
Where do the anterior and posterior roots join
The anterior and posterior roots join together at the intervertebral foramen to form the spinal nerve
696
When the spinal nerve emerges from the foramen what happens to it
When the spinal nerve emerges from the foramen and immediately divides into the anterior and posterior rami
697
What do both the anterior and posterior rami contain
The anterior and posterior rami contain both motor and sensory fibres
698
What is the cauda equina
The cauda equin is the lumbar and sacral nerve roots that terminate at the bottom of the spinal cord
699
Where do the spinal nerves leave the vertebral canal
The spinal nerves leave the vertebral canal through the intervertebral foramen
700
Anteriorly what is the intervertebral foramen bound to
Anteriorly the intervertebral foramen is bound by the bodies of the adjoining vertebrae and intervening intervertebral disc
701
Posteriorly what is the intervertebral foramen bound to
Posteriorly the intervertebral foramen is bound by the synovial joints between the 2 superior and 2 inferior articular processes
702
What is a spinal nerve root
A spinal nerve root
Each spinal nerve is formed by a dorsal and ventral nerve root
703
what is the dorsal root ganglion
The dorsal root ganglion are cells of origin of the dorsal root fibres reside here
704
What is the subarachnoid space
The subarachnoid space is the space between the arachnoid and the underlying pia mater containing cerebrospinal fluid
705
Where does the spinal cord end
Between the interval between the first and second lumbar vertebrae
706
What is the conus medullaris
The tapering end of the spinal cord
707
What is the filum terminale
The filum terminale is a fibrous strand extending from the conus medullaris to the coccyx
708
How can malignant tumours from breast and prostate reach the vertebrae of the spinal cord
These tumours can spread to the vertebrae through the vertebral venous plexuses which are connected to the veins draining these organs
709
What is a lumbar puncture
A lumbar puncture is a needle inserted into the subdural space in L3-L4 interspace which is the intercristal plane between the highest point of iliac crests on both sides
710
What would a lumbar puncture show
A lumbar puncture measures the opening pressure to diagnose idiopathic intracranial hypertension
711
What is the treatment for idiopathic intracranial hypertension
Cerebrospinal fluid drained to decrease the pressure
712
What can a lumbar puncture help diagnose
MS
Detect malignant infiltration
Diagnose infectious meningitis and encephalitis
Diagnose subarachnoid haemorrhage
