Week 1 - Neuroanatomy 1 of 4 Flashcards
1
Q
The two principal cell types of the nervous system are:
A
- neurons 2. Supporting cells
2
Q
Neurons are:
A
excitable cells that transmit electrical signals
3
Q
supporting cells are
A
cells that surround and wrap neurons
4
Q
another name for supporting cells
A
neuroglia or glial cells
5
Q
Function of supporting cells:
A
- provide supportive scaffolding for neurons - segregate and insulate neurons - *Guide young neurons to the proper connections - promote health and growth of neurons
6
Q
Name the 4 kinds of supporting cells
A
- Astrocytes 2. Microglia 3. Ependymal Cells 4. Oligodendrocytes
7
Q
Astrocytes are:
A
-star shaped -most abundant - versatile - glial cell (supporting cell)
8
Q
Astrocytes cling to neurons and their synaptic endings and cover _____. Forming the _____.
A
- cover capillaries - form the BBB
9
Q
Astrocytes 4 functions:
A
- Support and brace neurons 2. Anchor neurons to their nutrient supplies 3. Guide migration of young neurons 4. Control the chemical environment
10
Q
The most abundant CNS neuroglia are:
A
astrocytes
11
Q
Astrocytoma
A
most common brain tumor d/t the rapid turnover of cell growth/reproduction
12
Q
Describe Microglia
A
-small and white -oval shaped - have spiny processes
13
Q
Role of microglia
A
Protect from infection
14
Q
Protection from infection comes from what glial cells?
A
microglia
15
Q
Functional names of Microglia cells (2 types)
A
- Macrophages (Pacman) of CNS - immune sys and environmental health
- Phagocytes that monitor the health of neurons
16
Q
Ependymal cells shape
A
range from squamous to columnar
17
Q
Where are epdenymal cells found?
A
they line the central cavities of the - Brain & spinal column
18
Q
Like the choroid plexus, ependymal cells do what;
A
secrete CSF
19
Q
This cell secretes CSF
A
ependymal cells
20
Q
what cell has cilia with the function to help circulate CSF?
A
ependymal cells
21
Q
What feature of an ependymal cell is unique to the cells role in secretion and circulation of CSF?
A
they cilia
22
Q
Oligodendrocytes are similar to what other cell types?
A
Schwann and Satellite cells
23
Q
Oligodendrocytes and Schwann cells form
A
myelin sheaths
24
Q
Oligodendrocytes form myelin sheaths in the:
A
CNS
25
Schwann cells form myelin sheaths in the:
peripheral nervous system
26
What's the difference in Schwann cells and Olidgodendrocytes?
Where they form myelin sheaths: - schwann cells : PNS - Oligodendrocytes: CNS
27
role of myelination?
provide insulation "the coat around the nerve"
28
satellite cells surround cell bodies with
ganglia
29
The BBB is formed by 3 structures:
1. Astrocyte processes
2. Basement membrane
3. Very tight junctions b/w brain capillary endothelial cells
30
the BBB is the barrier b/w
cerebral capillary blood and the CSF
31
CSF fills what spaces:
- Ventricles - Subarachnoid space
32
The BBB consists of the endothelial cells of the
1. cerebral capillaries 2. choroid plexuses epithelium
33
Endothelial cells in cerebral blood vessels are joined together by
exceptionally "tight" junctions; nearly fused
34
The lack of ___ makes the BBB
pores
35
What can cross the BBB by carrier-mediated transport mechanism?
Glucose and amino acids
36
How do glucose and amino acids cross the BBB?
carrier mediated transport
37
Non-polar/lipid soluble substances cross the BBB by
diffusion
38
do non-polar/lipid soluble or polar/water soluble substances cross the BBB more readily?
non-polar/lipid soluble substances
39
Can CO2, O2 and anesthetics cross the BBB?
yes
40
Can ions, proteins, and large substances (i.e. mannitol) cross the BBB?
No
41
How does water move across the BBB?
freely - consequence of bulk flow.
42
How might the BBB be disrupted?
- Seizures - Strokes - HTN - Hypercapnia - Hypoxia - Infection - Tumors - Trauma "S.S.H.H.H.I.T.T." ;)
43
What areas of the brain do not have a BBB?
- Vomiting center - Hypothalamus (osmotic center) - \*chemical centers --- need blood for "testing"
44
Vasogenic Edema
- result from infarction - Destroys the BBB
45
What is Kernicterus
when bile/bilirubin crosses an immature BBB in a newborn - jaundice in a nb - damage basal ganglia
46
why is mannitol (hyper osmolar injection) given?
to open the BBB -for chemo --\> to open BBB for a short time to all the neoplastic agent to be available to a brain tumor
47
Functions of the BBB:
1. Maintain a constant environment for neurons - protects brain from endo/exogenous toxins 2. Prevents the escape of NT from their functional sites in the CNS in to the general circulation. 3. Allows Lipid soluble drugs to cross BBB readily (more so than water soluble drugs)
48
Inflammation, irradiation, and tumors may destroy the BBB and permit entry into the brain substances that....
are usually excluded - abx -radiolabeled markers
49
The brain is protected by:
1. bone 2. meninges 3. CSF
50
Harmful substances are shielded from the brain by the
BBB
51
The Dura Mater has two layers, what are they?
1. Periosteal 2. Meningeal
52
The meningeal layer of the Dura mater forms the
Superior sagittal Sinus
53
A sinus is a
dilated vein
54
The function of the superior sagittal sinus:
it is the venous drain for the brain. - for CSF
55
The meninges are:
three connective tissue membranes lie external to the CNS
56
Name the 3 meninges:
1. Dura Mater 2. Arachnoid mater 3. Pia Mater
57
Function of the meninges
1. cover and protect the CNS 2. protect blood vessels and enclose venous sinuses 3. contain CSF 4. form partitions within the skull
58
"Mother"
Mater
59
This meningeal layer is leathery, strong meninx composed of two fibrous connective tissue layers:
Dura Mater
60
The dura mater layers (periosteal & meningeal) separate in certain areas and form:
Dural Sinuses
61
Three dural septa extend inward and limit excessive movement of the brain. What are they?
1. Falx Cerebri 2. Falx Cerebelli 3. Tentorium Cerebelli
62
Falx Cerebri is a fold that dips into the
longitudinal fissure
63
Falx Cerebelli runs along the
vermis of theh cerebellum
64
Tentorium cerebelli is a
- horizontal dural fold - extends into the transverse fissure
65
"tentorium" means
tent like
66
Dips into the longitudinal fissure
Falx Cerebri
67
runs along the vermis of the cerebellum
falx cerebelli
68
horizontal dural fold extends into the transverse fissure
Tentorium cerebelli
69
Key words for three dural septa: Falx Cerebri: Falx Cerebelli: Tentorium cerebelli:
- Falx Cerebri: LONGITUDINAL fissure
- Falx Cerebelli: vermis of CEREBELLUM
- Tentorium cerebelli: HORIZONTAL fold; extends into TRANSVERSE (T:T) fissure
70
Is there separation at the pia mater?
no
71
Is there separation at the falx?
yes
72
Arachnoid granulations are :
- villous - found in the S. Sagittal sinus
73
Separation of Right and Left hemispheres:
Falx Cerebri
74
The middle meninx is
arachnoid mater
75
what separates the arachnoid mater from the dura mater?
subdural space
76
Role of subdural space
- separates dura mater from the arachnoid mater - filled with CSF - Large blood vessels
77
Where do arachnoid villi protrude?
superiorly into the venous sinus
78
why is it important to have CSF drainage?
maintain normal CSF /vol levels
79
This meninx layer is deep and delicate connective tissue. it clings tightly to the brain.
pia mater
80
Inflammation of the meninges is called;
meningitis (bacterial or viral)
81
meningitis is:
Inflammation of the meninges
82
Cranial Nerves Mnemonic
1. Oh 2. Oh 3. Oh 4. To 5. Touch 6. And 7. Feel 8. Very 9. Good 10. Velvet 11. Ah 12. Heaven
83
Cranial Nerves Sensory/Motor Mnemonic
1. Some 2. Say 3. Marry 4. Money 5. But 6. My 7. Brother 8. Says 9. Bad 10. Business 11. Marries 12. Money \*S - sensory, M- Motor, B- both
84
Cranial nerve I function type
- Olfactory - smell - sensory
85
Cranial nerve II function type
Optic Sight Sensory
86
Cranial nerve III function type
-Oculomotor - Eye movement, pupil constriction, accommodation, EYE LID OPENING - Motor
87
Cranial nerve IV function type
-Trochlear - Eye movement - motor
88
CN responsible for eye lid opening
CN III - oculomotor
89
Cranial nerve V function type
- Trigeminal - mastication, facial sensation - both S/M
90
Cranial nerve VI function type
- Abducens - eye movement - motor
91
Cranial nerve VII function type
- Facial - facial movement, anterior 2/3 taste, lacrimation, salivation, EYE LID CLOSING - both S/M
92
CN responsible for eye lid closing?
CN VII (7) Facial
93
Cranial nerve VIII function type
- Vestibulocochlear - hearing, balance - Sensory
94
Cranial nerve IX function type
- Glossopharyngeal - posterior 1/3 taste, swallowing, salivation, monitoring carotid bodies/sinuses - Both s/m
95
CN for anterior 2/3 tongue/taste?
CN VII - facial
96
CN for posterior 1/3 tongue/taste?
CN IX - glossopharyngeal
97
Cranial nerve X function type
Vagus - taste, swallowing, palate elevation, talking, thoraco-abdominal viscera -Both s/m
98
Cranial nerve XI function type
- Accessory -head turning, shoulder shrugging (trapezius) - motor
99
Cranial nerve XII function type
- hypoglossal - tongue movement - motor
100
damage to optic nerve causes
blindness
101
injury to oculomotor nerve can cause
-strabismus -ptosis - loss of light reflex
102
Trigeminal Neuralgia is also known as
"tic douloureux"
103
the most severe facial pain; "suicidal pain" is caused by
Trigeminal neuralgia
104
Trigeminal neuralgia involves
CN V and IX
V - Trigeminal
IX - glossopharyngeal
105
Bell's palsy is the result of:
paralysis of CN VII (7) - Facial nerve
106
Causes of Bell's Palsy -
- idiopathic/spontaneous paralysis of facial muscles - loss of taste - HSV1
107
Tx for Bell's Palsy
- may resolve spontaneously (comes and goes) - surgical decompression of VII nerve (steroid injection) \* monitor for Wide Open eye from not closing the eye --\> infections/ulcers. "SAVE THE EYE"
108
Damage of CV VIII results in
CN Vestibulocochlear - Nerve deafness
109
Damage to Vagus nerve --\>
hoarseness, loss of voice, impaired gut motility
110
Damage to CN XII:
CN Hypoglossal - tongue deviate to affected side - tongue movement restricted
111
Vertebral Column How many total Vertebra? How many vertebra in each section?
33 Vertebra - C:7 - T: 12 - L: 5 - S: 5 (fused) - Co: 4 (fused)
112
Functions of Vertebral column
- protect spinal cord, nerves - support body weight - posture and locomotion - variable shapes and sizes - join together by fibrocartilageous intervertebral (IV) discs
113
The Brain Stem leaves what to form spinal cord
medulla oblongata
114
these layers not only protect the brain, but also the spinal cord:
- Pia mater - Arachnoid mater - dura mater
115
Gray Matter:
the "butterfly" parts - gray commissure - posterior dorsal horn - anterior ventral horn - lateral horn
116
White matter:
- Posterior funiculus - Anterior funiculus - Lateral funiculus
117
Dorsal column tract
carries sensory modalities: - Fine touch - Vibration - Proprioception - Two point discrimination \*ascending tract?
118
sympathetic preganglionic neurons arise in the
intermediolateral horn of the spinal cord
119
All preganglionic fibers pass through the
white rami communicans in route to the paravertebral ganglia
120
What are the 3 "fates"/paths of preganglionic fibers:
1. through gray rami communicans to the spinal nerve 2. Ascend or descend in the paravertebral ganglia 3. pass through the paravertebral ganglia without synapsing. connect with peripheral ganglion.
121
Gray ramus function
sympathetic outflow - sympathetic postganglionic neurons pass through gray rami to reach the spinal nerve; travel to the skin to constrict skin arterioles and stimulate sweat glands.
122
C fibers
are sympathetic postganglionic neurons that pass through the gray rami
123
All sympathetic preganglionic fibers pass through the which rami while some, not all, sympathetic postganglionic fibers pass through
gray rami
124
Gray rami are distributed to
ALL spinal nerves
125
White ramie are distributed to
spinal nerves arising from T1-L2
126
Gray rami allow for:
coordinated, mass discharge of sympathetic nervous system.
127
\*Key to remember\* Grey goes...
Out. "Grey goes out" - Sympathetic response: Fight/Flight/Fright
128
Damage to the Inferior cervical ganglion leads to what syndrome?
Horner's syndrome
129
External carotid artery supplies blood to
face and muscles -outside of brain
130
Vertebral artery supplies blood to
vertebra and supply brain
131
Internal carotid artery supplies blood to
the brain
132
Horner's syndrome is a result of
destruction of stellate (inferior cervical) ganglion
133
Horner's Syndrome is a loss of ___ and the predominance of \_\_\_\_.
Loss of sympathetic tone and predominance of parasympathetic tone
134
S/S of Horner's Syndrome:
-Lesion above T1 P - Ptosis (drooping of eyelids) A - Anhidrosis (absence of sweating) M- Miosis (pupil constriction) E - Enophthalamos L - loss of ciliospinal reflex a "Horny PAMELa"
135
Common cause of Horner's Syndrome
scalene block -temporary on the side of injection/block
136
The spinal cord extends from the
foramen magnum to L1 in adults and L3 in new born \*\*moves up with age\*\*
137
how long is the spinal cord?
41-48 cm long
138
Spinal cord terminates at
L2 - conus medullaris
139
filum terminale extends down and anchors in the lower
sacral region
140
how many pairs or spinal nerves
31
141
Cauda equina is the nerve group in
lower dural sac (L1 - S5)
142
Describe the Supraspinous Ligament
-Strong fibrous Cord -Sacrum to C7 - Thickest and broadest in lumbar region
143
Describe the Interspinous Ligament
-Thing membranous ligament -Thickest and broadest in lumbar region -Full length of column
144
Short segments between spinous processes is the
The Ligamentum Flavum (yellow ligament)
145
The outermost, tough, fibrous tube of fibers; runs longitudinally -- this is the:
dura mater
146
This extends from the foramen magnum to S2 vertebrae
dura mater
147
What is a delicate, non-vascular, middle layer that extends to S2?
the arachnoid mater
148
The innermost, delicate, microscopic and highly vascular layer is the
Pia mater
149
this layer directly covers the roots of the spinal nerves
the pia mater
150
Non-vascular layer(s)?
Arachnoid (and dura?)
151
Vascular layer(s)?
pia mater
152
The space above the dura mate is:
the epidural space
153
Epidural space that surrounds
the meninges
154
Where is there NO epidural space?
cranium
155
the epidural space extends from where to where?
from foramen magnum to sacral hiatus
156
Ligamentum flavum bind the epidural space \*\*BOMB\*\*
posteriorly \*\*bomb\*\*
157
What binds the epidural space posteriorly?
ligamentum flavum
158
Where is the epidural space the widest? cm?
-L2 -5-6cm
159
Where is the epidural space the narrowest? cm?
-C5 - 1-1.5cm
160
What is a potential/hidden space that can be opened by the separation of the arachnoid mater from dura mater?
the subdural space
161
The subdural space can form as a result of :
-Trauma - \> subdural hematoma -Pathologic process (tumor) -Absence of CSF (cadaver) where arachnoid mater falls away from the dura mater
162
Subarachnoid space lies b/w
arachnoid mater and pia mater
163
The space b/w the arachnoid and pia maters is the:
subarachnoid space
164
CSF is found in the
subarachnoid space
165
Where does blood supply to the spinal cord and nerve roots come from?
- Single Anterior spinal artery - Paried posterior spinal arteries
166
The principle site of action of neuraxial blockage is the:
nerve roots
167
Identify the following: -Epidural Space -Supraspinous ligament -Ligamentum flavum -Dura -Subarachnoid space -Vertebrae -Intervertebral Disk - Arachnoid membrane -Interspinous Ligament
1 -Epidural Space 2-Supraspinous ligament 3 -Ligamentum flavum 6 -Dura 7 -Subarachnoid space 9 -Vertebrae 8 -Intervertebral Disk 5- Arachnoid membrane 4-Interspinous Ligament
168
Lumbar Puncture - purpose? - position? - obtained from? - Structures?
- to obtain CSF - spine flexion ("shrimp") - from lumbar subarachnoid space b/w L4-L5. - Skin, sq tissue, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space, dura, subdural space, arachnoid mater, subarachnoid space
169
"Tuffier's line"
anatomical landmark L4 superior aspect of iliac crest
170
Substantia Gelatinosa is located? function?
-Laminae II - Posterior column -Pain relief area
171
how many mixed nerves arise from the spinal cord?
31 pairs
172
what parts of the body do the spinal nerves supply?
all parts of the body EXCEPT the HEAD
173
Spinal nerves are named according to
their point of issue
174
name and number of all spinal nerve (segments):
8 cervical (c1-c8) 12 thoracic (T1-T12) 5 Lumbar (L1-L5) 5 Sacral (S1-S5) 1 Coccygeal (C0)
