Gross Brain Lecture Flashcards
1
Q
proximal vs distal
A
Proximal=closer
Distal=away
2
Q
Caudal vs rostral
A
Caudal=towards tail
Rostral=towards head
3
Q
Lateral Fissure
A
1) AKA sylvian fissure
2) Separates the frontal and parietal cortices from the temporal cortex
4
Q
Operculum
A
1) Regions of cerebrum bordering the lateral fissure
2) Ex: frontal, parietal, or temporal operculum
5
Q
Corpus Callosum
A
1) Myelinated axons that connect cerebral hemispheres
2) White matter
6
Q
Grey Matter
A
Regions of the CNS containing a high density of neuron cell bodies
7
Q
White Matter
A
Regions of the CNS containing a high density of myelinated fiber tracts(axons)
8
Q
Thalamus
A
1) Bilateral Subcoritcal structure
2) relay of information to and from cerebral cortex; except olfaction goes to cerebral cortex first then thalamus
- sexual behavior
- feeding
- hormonal output of pituitary gland
- body temp regulation
3) Aka diencephalon
9
Q
Cerebellum
- location
- function
A
1) Suprasegmental structure-superior and dorsal (away from) to brainstem
2) Coordination
10
Q
Choroid Plexus
A
1) Produces CSF
2) located:
- Body and inferior horn of lateral ventricles
- 3rd ventricle
- 4th ventricle
11
Q
Ventricular System: CSF Flow
A
Lady Monro’s Third Child Forced Magendie & Lushka to Say Ass & Shit
1) Lateral Ventricles
2) Interventricular foramen (Foramen of Monro)
3) Third Ventricle
4) Cerebral Aqueduct
5) Fourth Ventricle
6) Median Aperature (Foramen of Magendie)
or Lateral APerature (Foramen of Lushka)
7) Subarachnoid space
8) Arachnoid Granulations/Villus
9) Superior Sagittal Sinus
12
Q
Where is the 3rd ventricle located?
A
1) on the Midline of the brain, between the thalamus and hypothalamus
2) continuous with cerebral aqueduct
13
Q
Median and Lateral Aperatures
A
1) Median Aperature (foramen of Magendie) -not bilateral 2) Lateral Aperature (Foramen of Lushka) -bilateral 3) open into subarachnoid space -bathe the outer surface of brain and Spinal cord with CSF
14
Q
Where is the 4th ventricle located?
A
1) Between the pons/medulla and the cerebellum
15
Q
What are the 3 routes that CSF flows from the fourth ventricle?
A
1) Median Aperature
- not bilateral
- Foramen of Magendie
2) Lateral Aperature
- bilateral
- Foramen of Lushka
3) Central canal of medulla and spinal cord
- not open/patent
16
Q
Trigon area of Lateral Ventricle
A
1) b/w posterior and inferior horn
2) Calcified glomus
3) Common for adults
17
Q
Arachnoid Villus
A
1) Aka arachnoid Granulations
2) protrude into SSS (dural sinus)
3) site of absorption of CSF into systemic circulation (SSS)
18
Q
Stenosis
A
Squeezing/making aperture smaller
-impeding flow
19
Q
Dura Mater
A
1)outermost and thickest
2) fused with internal periosteum and doesn’t follow contour of brain
3) 2 layers
meningeal layer-inner layer
-fold of this layer form septa that divide cranial cavity
-falx cerebri, tentorium cerebelli, falx cerebelli, diaphgrama sella
periosteal/endosteal layer-outer later
- stops at foramen magnum and fuses with occipital bone
- *layers not easily seperable except venous sinus
20
Q
Arachnoid membrane
A
1) lines the dura mater
2) doesn’t follow the contour of the Brain
21
Q
Subarachnoid Space
A
1) Contains major arteries and veins that supply the CNS
22
Q
Pia Matter
A
1) vascularized, areolar membrane
2) extends enter every sulcus and fissure of brain
3) Very thin and transparent
23
Q
Relationship of neurons/axons
A
Direct relationship between:
- diameter of axon
- thickness of myelin sheath
- distance between nodes of the myeline sheath (nodes of Ranvier)
- conduction velocity of nerve fiber
24
Q
Large diameter axons vs thin diameter axons
A
1) large diameter axons
- thick myelin sheaths
- longer internal distances (nodes of ranvier)
- EXHIBIT faster conduction velocities
2) Thin diameter axons
- thin myelin sheaths
- shorter internodal distances
- slower conduction velocities
3) Smallest axons
- no mylein
- slowest conduction velocities
25
Cell types of Nervous System
Neurons and glial cells
26
Neurons
1) Basic structural and functional unit of the nervous system
2) Consists of a:
- cellbody (soma or perikaryon)-gray matter
- dendrites-processes off of cell body
- axons- single process to other areas (white matter(
27
Myelin
insulting lipoprotein
28
Areflexia
lack of reflex
29
Hyporeflexia
weakened reflex
30
Hyperreflexia
excessively active reflex
| -indicative of neurologic disorder
31
Medulla Oblongata
1) aka medulla
2) consists of:
- neurons that perform functions associated with the medulla
- asscending (sensory) and descending (motor) tracts
32
Forebrain composed of:
1) Cerebral hemisphere
2) basal nuclei
3) Thalamus
33
What is the location of the thalamus?
1) rostral to midbrain
| 2) Surrounded by cerebral hemisphere
34
Cerebral Cortex
1) layer of cell bodies
| 2) .5 cm thick
35
Subcortical White matter
1) 2nd layer of cerebral hemisphere
2) basal nuclei
- motor function
36
Afferent
conduction of signal toward a structure
| -incoming piece of info
37
efferent
conduction away from structure
| -sending info
38
Medial
toward or at the midline
39
Lateral
away fro midline
40
Cerebral hemisphere:
- posterior/doral
- santerior/ventral
- rostral
- caudal
1) Posteior/dorsal
- toward the top of the brain
2) Anterior/ventral
- base of the brain
3) Rostral
- toward frontal pole
4) Caudal
- toward occipital pole
41
Sympotom vs signs
1) Symptom
- deviation from normal that is stated by patient
- subjective indicator
2) Sign
- deviation from normal that is stated by physician
- objective indicator
42
Multiple Sclerosis
1) Demyelinating disease
2) Oligodendrocytes and their myelin segments degenerate
- replaced by astrocytic plaque
3) Loss of myelin result in an interruption of propagation of action potentials down these axons
43
Compression injury
1) Axonotmesis
| - crushed peripheral nerve
44
Transection injury
1) Neurotmesis
| - severed peripheral nerve
45
Traumatic neuroma
1) Phantom pain in people with ampuateed limbs
| - neuroma developed in amputated limb
46
Norepinephrine
1) NT
- regulation of the sympathetic division of autonomic nervous system
- in peripheral nervous system binds to a- and B-adrenergic receptors
47
What is the greatest source of norepinephrine in the mammalian CNS?
Locus Ceruleus
48
Reserpine
1) plant alkaloid
- inhibits dopamine and norepinephrine
2) Irreversibly inactivates the monoamine-H+ transporter
- tranports dopamine in synaptic vesicle-> norepinephrine
3) Earliest therapeutic agents for treatment of hypertensive cardiovascular disease
4) Causes noradrenergic neurons:
- innervate arteriolar smooth muscle to produce less NE=vasoconstriction -overall reduction in BP
- reduced ability to stimulate noradrenergic cardiac neurons which cOuld increase heart rate->lower cardiacs output
5) cause early onset of parinksons symptoms
6) worse clinical depression
7) Rarely used today to treat hypertension
49
A-methyldopa
1) Aldomet
2) Reduces accumulation of dopamine and NE in synaptic vesicles
3) Effect antihypertensive drugs during pregnancy
4) converted to a-methyldopamine and a-methynorepinephrine
- reduct of noradrenergic transmission
50
Guanethidine
1) Reserpine like
- inactivate vesicular transport
2) Released among of NE released
3) reduced heart rate, nasal congestion, orthostatic hypotension
51
Yohimbine
1) Similar to reserpine
2) Blocks a2-adrenergic receptors
- inhibitor effect over the amount of NE released
3) Loss of auto inhibition increass the amount of NE released
4) Found in herbal as a aphrodisiac
5) Promote erectile funciotn in male patients
- wihtout vascular diabetic or psychogenic origin
52
Psychomotor stimulant drugs
```
1) include:
cocaine and amphetamines
2) enhance motor performance
-relieve fatigure
-exert positive reinforcing effects by enhancing conc of monoamines
```
53
Cocaine
1) reversible inhibition fo membrane monoamine transports
| - reduce reabsorption of monoamines out of synaptic cleft
54
Amphetamines
1) enhances release of monoamines by promoting movement of cytoplasmic monoamines into synapse
2) inhibits monoamine oxidase
- MAO-A (periphery)
- MOA-B (brain)
55
Tranyllcypromine
1) aka partite
2) and Phenelzine (Nardil)
2) Both are nonselective inhibits that block both MAO-A and MAO-B
3) Used to treat major depressive disease
56
Selegiline
AKA L-deprenyl, Eldepryl
2) selective inhibitor of MAO-B
- blocks mitochondria degradation of dopamine in the CNS
3) Management of Parkinsons
57
Tyramine
1) Displace NE from cytoplasmic pool back into the synapse
| - enhancing noreadrenergic activity
58
Hydrocephalus
1) Characterized by:
- increase in CSF volumes
- enlargement of one or more of the ventricles
- Increase in CSF pressure
2) Neurological deficits
- seen in fetus or in new born
59
Hydrocephalus: Occlusion of cerebral aqueduct during development may be the result of:
1) Glial scarring (Gliosis) due to infection
2) developmental defect of the forebrain
3) rupturing of the amnionic sac in utero
4) forking of aqueduct
60
Obstructive Hydrocephalus
1) May result from obstruction within ventricular system or within subarachnoid space
2) Common intraventricular site of potential obstruction are:
- interventricular foramen
- cerebral aqueduct
- caudal portions of the 4th ventricle
- foramen of fourth ventricle
3) Extraventricular obstruction occurs at any place in subarachnoid space but is more common:
- base of brain
- tentorium cerebelli
- tentorial notch
- over the convexity of the hemisphere
- Superior Sagittal Sinus
61
Aqueductal Stenosis
1) tumor in the immediate vicinity of the midbrain
- meningioma
- pineoblastoma
2) Or could be occluded by cellular debris seen following:
- interventricular hemorrhage
- bacterial or fungal infections
- ependymal proliferation due to viral infections of CNS (mumps)
3) Major condition due to this:
- Triventricular hydrocephalus- enlargement of the third and lateral ventricles
4) Obstruction of excit channels of the fourth ventricle
- foramina of magendie
- foramina of lushka
- results in enlargement of all parts of ventricular system
62
Communicating Hydrocephalus
1) Flow of CSF through ventricular system into subarachnoid space is not impaired
2) Movement of CSF through subarachnoid space and into venous system is partially or totally block=HIGH CSF PRESURE; due to:
- Agenesis (congenital absence) of arachnoid villi
- Villi may be partially blocked by RBC following subarachnoid hemorrhage or CNS infection (leptomeningitis)
5) high level of proteins in CSF (above 500mg/dL) seen with CNS tumors or inflammation
6) All situations
- enlargement of all parts of the ventricular system
63
Hydrocephalus ex Vacuo
1) no true hydrocephalus
| 2) no increase in intracranial pressure
64
Idiopathic Intracranial Hypertension
1) PSeuotumor cerebri
2) most commonly seen in obese women of child bearing age w/chronic renal failure
3) Vit A toxicity possible related
4) Increase in Intracranial Pressure (>25cm H2O)
- little evidence of pressure increase on CT or MRI scans
5) Experience headache and variety of visual deficits (up to blindness) due to papilledema (swelling of optic disc)
65
Normal Pressure Hydrocephalus
1) Cause is unclear
2) CSF elevated spisodically
3) Usually elderly patients
4) Intracranial pressure may initially be elevated and ventricles enlarged, pressure my wax and wane over time or even subside to a High normal level
- effects of increase pressure remain
5) Can mimic Alzheimer and Parkinsons due to combination of difficulty shuffling gait and dementia
66
Hemorrhage into ventricles
1) Events resulting in blood accumulating in ventricular spaces in the brain
-Ruptur of intracranial aneurysm (adjacent to 3rd and 4th ventricles)
-severe head trauma (blood in subarachnoid space originate n the brain depending of degree of injury)
-Hemorrhage into Brain (cerebral hemorrhage) the ruptures in ventricular space
2) blood in ventricles
-especially acute bood
-seen clearly on CT
White appearance outlines the ventricular space
67
Ependymomas
1) 5-6% of glial cell neoplasm
2) Tumor arise from ependymal cell lining ventricles
3) can appear in ventricles, but majority (60-75%) in posterior cranial fossa
- spinal cord
- region of caudal equine
4) Seen most frequently in children younger than 5
5) Location determines symptoms
6) True Rosettes
68
Tumors of Choroid Plexus
1) rare
- less than 1% of all intracranial tumors
2) Lesions classified as:
- choroid plexus papillomas-benign-frequently seen-> Surgical removal
- choroid plexus carcinomas- maligant-rare-> tx more aggressive; 1) chemotherapy 2) Surgery) combination of chemo and radiation
3) Seen in patients of any age
- most common between birth and 10 years old
4) Most often occur in:
- 4th ventricle (50-60%)
- lateral ventricles
69
CSF vs blood plasma contents
```
CSF
Higher concentrations:
- Cl-
-Magneisum
-Na (sodium)
-similar concentrations of creatinine
```
Lower conc:
- potassium (K)
- calcium (Ca)
- glucose
- proteins
- albumin
- uric acid
70
Normal CSF
1) Deviation from Normal state is indicative of of pathologic statE
2) Clear and colorless
- very little protein
- little immunoglobulin
- only 1 to 5 cells (leukocytes) per milliliter
71
Lumbar Puncture
1) collect a sample of CSF for analysis and to measure CSF pressure
2) needle inserted between the third and fourth (or fourth and fifth) lumbar vertebrae into dural sac
- few milliliters of fluid is withdrawn
3) Bc average volume of CSF in adult=120mL/day
- rate of production is 450-5000mL/day
- sample removed is quickly replaced
4) If blood in sample
- is this due to subarachnoid hemorrhage or due to damage to a vessel during procedure (traumatic tap)
72
How to determine the blood in CSF is due to subarachnoid hemorrhage or traumatic tap?
1) 3 tube tests
- 3 successive tubes of CSF is drawn
2) example A=Traumatic Tap
- 1st tube contains blood
- 2nd tube contains little or none
- 3rd -none
3) Subarachnoid hemorrhage
- all 3 tubes contain bloody CSF and xanthochromic
73
bacterial Meningitis: number of cells in CSF
1) Neutrophils predominate
- 1000-2000/mL
2) CSF is cloudy
74
Spyphilitic meningitis: number of cells in CSF
1) Lymphocytes predominate
| - 50-100/mL
75
Epidural Space
1) not normally present
2) Between dura and skull
3) opened by ruptured meningeal artery
- ex: middle meningeal artery
- run in the periosteal layer of the dura
4) Rupture=Epidural Hematoma
- deadly
76
Subdural Space
1) not normally present
2) Between dura and arachnoid
3) Opened by cerebral vein as it enters dural sinus
4) Subdural Hematoma
- slow rate of blood loss
77
Middle Meningeal Artery
1) causes Epidural Hematoma
2) enters Cranium via Foramen spinosum then bifurcates into anterior and posterior
- anterior goes through pterion (vulnerable area)
3) Blood supply to calveria (skull and dura)
78
Falx Cerebri
Dural Reflection
| -between the 2 cerebral hemispheres
79
Tentorium Cerebelli
Dural extension
- superior to cerebellum
- covers cerebellum in posterior cranial fossa
- straight sinus found within
80
Falx Cerebelli
1) extends vertically downward between the two cerebellar hemispheres
81
Diaphgragma Sellae
1) extends between anterior and posterior clinics processes
| - covers pituitary gland
82
Tentorial Incisure
1) Oval opening in tentorium cerebelli
| - allows passage of the brainstem into posterior cranial fossa=midbrain
83
Dural Reflections
1) Falx Cerebri
2) Tentorium Cerebelli
3) Falx Cerebelli
4) Diaphragm Sellae
- attached to cranium
- mechanically support brain
84
Dural Sinuses:
1) Generally gaps between the meningeal and periosteal layers of dura; EXCEPT
-inferior sagittal sinus
-Straight sinuses
located between to layers of meningeal dura
2) All empty into the internal jugular vein
85
Superficial Veins:
1) Variable
2) Drain superfici regions of the cerebrum into SSS, transverse sinus, cavernous sinus or petrosal sinuses
3) these veins are constant
- Superficial Middle Cerebral Vein
- Superior Anastomic vein of Trolard
- Inferior Anatomic vein of Labbe
86
Superficial Middle Cerebral Vein
1) Constant superficial vein
2) runs anteriorly and inferiorly along lateral fissure
3) drains most of the temporal lobe into cavernous sinus
87
Superior Anastomic Vein of Trolard
1) Constant superficial vein
2) runs across parietal lobe
3) connects the superficial middle cerebral vein with SSS
88
Inferior Anastomic Vein of Labbe
1) Constant Superficial Vein
2) runs posteriorly and inferiorly across temporal and/or occipital lobes
3) Connects superficial middle cerebral vein w/transverse sinus
89
Deep Veins
1) More constant than superficial veins
- internal cerebral vein
- great cerebral vein
- basal vein of rosenthal
90
Internal Cerebral Vein
1) constant deep vein
2) formed at the interventricular foramen from 2 smaller veins
3) Travels posteriorly along medial wall of thalami
91
Great Cerebral Vein of Galen
1) Constant Deep vein
2) formed by the Jxn of right and left internal cerebral veins
3) joins inferior sagitall sinus to form straight sinus
92
Basal Vein of Rosenthal
1) Constant Deep vein
2) formed near the optic chiasm and hugs around midbrain
3) runs posteriorly and enters the great cerebral vein of Galen->straight sinus
93
What courses through the internal acoustic meatus?
CN 7 and 8
94
What courses through the jugular foramen?
CN 9, 10, 11 and Jugular Vein
95
Thalamostriate vein
1) runs to Venous Angle-> Interventricular Foramen-> Internal Cerebral Vein
2) Drains lateral ventricle
96
Subdural Hemorrhage
1) AKA extradural hemorrhage
2) Most common causes: trauma to head w/or without skull fracture
-periosteal dura may be loosed from the skull w/consequent damage to a major artery
-middle and accessory meningeal arteries
3) Forms epidural or extradural hematoma
4) Lenticular shaped
-short and wide
5) neurological deficits due to increased intracranial pressure: In order of occurring
-headache
-confusion and disorientation
-lethargy
-state of unresponsiveness
6) some cases of head trauma:
-pt initially unconscious followed by lucid interval (pt awake and chatty)then detoriates rapid and dies
=TALK and DIE
97
Subdural Hemorrage
1) bleeding into the meninges b/w arachnoid and dura
- venous structures
2) common cause
- tearing of bridging veins as they pass through subarachnoid space and enter dural venous sinus
3) leading to Subdural Hematomma or "Dural Border Hematoma
- appear long and thin
- splits open the dural border cell layer
- creates space between dura and arachnoid
4) lesions:
- blood in their central area and myofibroblasts, fibroblasts, mast cells, proliferating blood vessels and dura border cells
98
Subarachnoid Hemorrhage
1) Usually Arterial blood in subarachnoid space
2) most common cause:
trauma
-large blood veins
nontruamatic/sponataneous common cause
- rupture of intracranial aneurysm
- clearly defined dilation in walls of arteries
- can be congenital or ongoing pathologic process or trauma or secondary to a general systemic problem (hypertension)
- most common In 40-65 yr old
3) About 1/3 of affect parties die before or sooner after admission to doctor
- 1/3 have permanent and significant disablities (cognitive/motor)
- 1/3 recover with minimal neurologic sequelae
4) Signaling Symptoms:
- sudden excruciating headache
- neck stiffness
- vomitting or nausea
- depression or lack of consciousness
5) Pts who are not unconscious decribe headache as "explosive and awful"
6) Warning signs and symptoms:
- intermittent headache
- nausea or vomitting
- syncope (fainting spells)
7) Diagnosis
- Bloody CSF obtain by lunar or cisternal puncture
- blood in subarachnoid space on CT exam
8) Tx for aneurysm
- clip aneurysm or stalk
- seperating it from cerebral circulation
99
Bacterial Meningitis
Bacterial
1) infection most often located in subarachnoid space and involves leptominenges
2) caused by:
- trauma (introduce bacteria into the head or spine),
- septicemia
- metastatis from another site of infection of the body
3) generally classified as:
- acute
- subacute
- depending on how rapidly the disease is spreading
Acute:
4) Signs of Acute meningitis:
- elevated Temp
- slternating child and fever
- headaches
- acutely ill and may have depressed lack of consciousness
5) Signs and symptoms seen with:
- increased CSF pressure
- cloudy CSF containing may WBC
- increased Protein
- bacteria
5) Most common causative agent: 75%
- streptococcus pneumoniae
- Neisseria Meningitides
6) Inflammatory response
- thickening of leptomeninges
- partial obstruction of CSF flow
- signs of hydrocephalus
7) Death rate low in acute cases w/proper treatment
- pt can become ill suddenly and die within 2 days in advance cases
Subacute:
1) usuallly seen in patients with tuberculosis or mycotic infection
2) longer course
- weeks instead of days
- slow onset
3) Characterized by:
- headache
- fever
- irritability
- wakefullness at night
IN BOTH:
-prognosis is excellent (90%) cure rate w/ early diagnosis and proper treatment
100
Viral Meningitis
1) caused by a range of viral agents
2) Most commonly seen in:
- younger patients (<25 y.o.)
3) No antiviral meds are available
4) Symptoms:
- fever
- headaches
- increasing intensity
- confusion and possibly an altered level of consciousness
5) rare cases serious symptoms and signs
- seizuire
- rigidity
- cranial nerve palsies
6) Mild Case Tx:
- supportive
- medicines focused on fever, pain, and general discomfort
7) after acute period of 1-2 weeks:
- signs and symptoms moderate
- pt recovers w/o permanent deficits
101
Meningitis
1) Viral or bacterial origin
102
Brain and Vascular need
| -oxygen
1) 50% of problems that occur inside the canal cavity result in neurological deficits are from vascular origin
2) Brain receives 15-17% of total cardiac output and consumes 20% of oxygen used by entire body
3) Average person lose conscious if brain is deprived of blood for 10-12 seconds
4) After 3 to 5 mins-irreparable brain damage or death
103
Hypothermic Patients
1) decrease in arterial blood flow to brain
| - can be revived 10-20 mins with little or no permanent damage
104
Aneurysm
1) dilation of vessel walls
- usually an artery
- included all layers of vessels wall
2) Sacular
- bery like
- where arteries branch
- likely to rupture
- can range from small to very large (>2cm diameter)
3) Fusiform
- spindle shaped
- not a problem/unlikely to rupture
4) Second most common cause of subarachnoid hemorrhage
- blood in subarachnoid space
5) Most intracranial/cerebral aneurysms are found on the branches of internal carotid artery system:
- Anterior Communicating Artery (most common) or junction with anterior cerebral artery
- internal carotid artery or junction with posterior communicating artery
- Bifurcation of the M1 segment of MCA
6) 10-15 % located on the branches of the vertebrobasilar system:
- bifurcation of the basilar artery
- on basilar artery
- PICA or Jxn with vertebral artery
7) Tx:
- clip the stalk of the aneurysm
- seperates its sac from the cerebral circulation
105
Cerebral Embolism
1) Occlusion of a cerebral vessel by some extraneous material:
-clot, tumor, clump of bacteria, air, plaque fragments
2) Leads to ischemia (localized anemia)
-if prolonged= infarction of the area served by the vessel
(localized vascular deficiency)
3) Seen in patients with atherosclerotic disease
106
Thrombus
1) embolus made up of only blood products
2) Size determines where it lodges
3) Small emboli
- temporarily occlusion small cerebral vessels and give rise to TRANSIENT ISCHEMIC ATTACK
- a sudden lord of neurologic function
- resolves within a few minutes -70% percent of cases
- resolves a few hours (20 %)
- rarely up to 24 hours
4) large emboli
- occlude major vessels result in permanent deficits or even death
107
Septic Emboli
1) composed of bacteria usually originating from extra cranial location
2) Results in:
-interruption of blood supply-> infarction
OR
-infection within CNS once the bacteria becomes lodges a vessel
3) Can also infect and weaken the vessel wall itself
=MYCOTIC ANEURYSM
-AKA Fungal Aneurysm
108
Air embolism
1) surgical procedures where the dural sinus is opened
- air enters the sinus
- movemnt of blood through sinus is compromised
- if air gets into general vascular system and hear other serious problems may arise
109
List all the sinuses:
```
Superior sagittal
Inferior Sagittal
Tranverse
Sigmoid
Superior Petrosal
Inferior Petrosal
Cavernous
Straight
Sphenoparietal
```
110
Circle of willis
1) branches of internal carotid arteries and vertebral arteries
2) Example of arterial anastomosis
3) Normally little blood flow around circle of willis
4) occlusion of vessel in the circle of willis or supplying it:
- communicating arteries swell
- allow anatomic flow to compensate for occlusion
111
Anterior Cerebral artery mainly supplies:
Medial Structures of Cerebrum
112
Middle Cerebral Artery mainly supplies:
lateral regions of cerebrum
113
Posterior Cerebral Artery mainly supplies:
occipital lobe
114
Anterior Spinal Artery
1) originates in the midline from the 2 vertebral arteries
| 2) Supplies the more superior portion of the spinal cord
115
Septum Pellucidum
1) Thin membrane
2) Midline
3) Medial wall of anterior horn of lateral ventricle
116
Lamina Terminalis
1) Rostral walls of Third ventricle
117
Anterior Cranial Fossa
1) Frontal Lobe
2) CN1
3) part CN2
118
Middle Cranial Fossa
1) Parts of CN 2,5,6
| 2 ALL CN 3 and 4
119
Posterior Cranial Fossa
1) Cerebellum
2) Brainstem
3) Part of CN5 and 6
4) All of CN 7-12
120
Reticular Formation
gives us consciousness
121
Intracranial pressure
```
1) Normal-
0-10 mmHg
2) Neurologic Disfunction
40mmHg
3) Fatal
-60mmHg
```
