ch. 8 cns Flashcards
The central nervous system includes the ____ & ____.
- Brain
2. Spinal chord
what are neurons
nerve cells
What is neuroglia
Interstitual tissue
The CNS is compose of
- ____
- ____
neurons (nerve cells)
2. Neuroglia ( Interstitual tissue)
what are the 3 basic components of a neuron
- Cell body (soma)
- Dendrites
- Axons
what makes up the brain
- Cerebrum
- Cerebellum
- Diencephalon
- Brianstem ( midbrain, pons, medulla oblongata)
the brainstem connects the ____ with the spinal chord
cerebrum
_____ is an extension of the medulla oblongata
spinal chord
Describe the spinal chord
extension of medulla oblongata.
Extends from the foramen magnum to the 2nd / 3rd Lumbar vertebrae
Terminates with a cone shaped area called the conus medullaris
Spinal chord and terminates with a cone-shaped area called the ____.
conus medullaris
what is the conus medullaris
cone shape area in which the spinal chord terminates in
Spinal nerves beyond the point of conus medullaris is known as ____
cauda equina
What is cauda equina
Spinal nerves beyond the point of conus medullaris
The brain and the spinal chrod are covered by the ____
meninges
What are the 3 layers of the meninges
- Dura matter (outtermost layer)
- Arachnoid ( middle layer)
- Pia matter (innermost layer)
____ layer of the meminges is the outer most, tough and fibrous
dura matter
____ is the middle layer of the meninges and has cobweb appearance
arachnoid layer
___ is innermost layer of the meninges that adheres directly to the spinal chord and the brain
Pia matter
____ is located between the arachnoid and the pia matter
Function___
subarachnoid layer
Filled with CSF (cerebral spinal fluid)
Cavities that are connected to one another in the brain are known as ____
ventricles
what are ventricles
Cavities that are connected to one another in the brain
what secretes CSF into the subarachnoid space
choroid plexus (housed in the ventricles )
What are the s4 ventricles of the the brain
- Lateral ventricles
- 3rd ventricle
- 4th ventricle
Most of the brain’s blood is supplied anterioly via ___
and posterior via ___
Bilateral internal carotid arteries ( ant.)
bilateral vertebral arteries ( post. )
what is the circle of willis
Formed by Basilar artery and internal carotid arteries
*distributes oxygenated aterial blood through the brain
venous blood drains into the ____
jugular veins
what is a blood brain barrier
function of capillaries that protects the brain by removing waste and keeping toxins out
What is the primary tissue comprising the nervous system
neurons
are intervertebral disk apart of CNS
no but they may come in contact with it when they herniate and impinge on adjacent spinal nerves
Describe intervertebral disk
Function:____
Made of____
- Cushion movement of vertebral column
2. annulus fibrosus ( outer) Nucleus pulposus ( center)
the pulpy center of a intervertebral disk is called _____
nucleus pulposus
Tough outer covering of an intervertebral disk is kown as ___
Annulus fibrosus
What is the modality of choice for conditions related to CNS
MRI
____ is useful in evaluating the brains of neonates
sonography
____ evaluates cranial trauma
radiography
______ useful in evaluating cerebral bleeding after trauma
CT
___ are primarily used to confirm brain death in patients
radionuclide brain scans
Vascular brain and neck study
cerebral angiography
What is meningomyelocele
Def:____
Classification:___
Pathology:____
Both spinal chord and meninges protrude into the skin on the back
Congenital
None
What is meningocele
Def:
Classification:
Patholgoy:
Protrussion of only the meninges through the spinal column
Congenital
none
Protrussion of only the meninges
Through the spinal column
meningocele
congential
none
Both spinal chord and meninges protrude into the skin on the back
meningomyelocele
aka spina bifida
*most serious
congenital
none
Protrussion of only the spinal chord
Classification
pathology
myeolcele
congenital
none
what is myelocele
Def:
Classificaiton
pathology
Protrussion of only the spinal chord
congenital
none
Which is most serious
- Meningomyelocele
- Meningocele
- Myelocele
- Meningomyelocele
Incomplete closure of the bony neural arch in the lumbar region
spina bifida
excessive CSF accumalation in the ventricles of the brain
hyrdrocephalus
What is hydrocephalus
Def: Causes Classification : Pathology : Exam to diagnose
Excessive CSF accumulation in the ventricles of the brain
- 2 causes:
- **1. Noncomunication = obstruction to flow
- **2. Communicating= impaired absorption
Congenital
None
CT
Name two ways that hydrocephalus can occur
- Noncommunicating= obstruction to flow
2. Communicating= imparied absorption
artificial passageway used for hydrocephalus treatment
Shunt
Inflammation of the meninges
Meningitis
Define meningitis
Classification:
Pathology
Exam to diagnose
inflammation of the meninges
Inflammatory
none
Spinal tap
What is the most common cause of meningitis
bacterial infection
Infection of brain tissue that can occur from chickenpox or influenza
Encephalitis
usually viral
What is encephalitis
Exam to diagnose
infection of brain tissue that can occur from chichenpox and influenza
*Usually viral
MRI
Pus within the cranium that occurs from a cranium infection
Classification
Pathology
Exam to diagnose
Brain abscess
Inflammatory
None
MRI
Which condition is more serious Encephalitis or meningitis
why
Encephalitis because it can result in permanent neurologic disabilities
Pus from abscess within the meningeal layers is termed ____
subdural empyema
Protrusion of nucleus pulposus through a weakened part of intervertebral disk that compresses spinal nerve roots
herniated nucleus pulposus
aka: herniated disk
What is herniated nucleus pulposus
Classificaiton
pathology
Exam to diagnose
Protrusion of nucleus pulposus through the a weakened part of the disk that compresses the spinal nerve roots
Degenerative
none
MRI
where are most common locations for disk herniation
lower cervical (C6-C7) and lower lumbar regions (L5-S1)
osteoarthritic changes in the neck are known as
exam
cervical spondylosis
Seen on oblique projection of cervical spine
X-ray
Cervical spondylosis are seen on ____ projection of C-spine
oblique
nervous system Disease degernates the myelin sheath and white matter impairing nerve conduction
Classification
Pathology
Exam to diagnose
Multiple sclerosis
Degenerative
None
MRI
Define Multiple sclerosis
Disease of the nervous system that degenerates the myelin sheath and white matter impairing nerve conduction
Cerebral Vascular Accident is commonly referred to as a _____
Classification
pathology
stroke
Classified in 2 ways:
Ischemic( blood vessel blocked by blood clot)
Hemmorrhagic = rupture of weakened blood vessel in the brain that leads to bleeding into other structures
Degenerative
None
Which type of stroke has a more sudden onset
hemorragic
= rupture of weakened blood vessel in the brain which causes bleeding into other structures
why are ischemic strokes dangerous
because it causes block to blood flow and cause vessel occlusion
Name the 2 ways an ischemic stroke can occur
- Infarction= Cerebral artery blood clot
2. Embolism to the brain caused by a blood clot formed elsewhere in the body
blood clot that obstructs a blood vessel
thrombus
mass in a blood vessel
embolism
Term for small vessel disease
lacunar infarction (type of thrombosis)
What is TIA
Transient Ischemic attack
Temporary episode of neurologic dysfunction
Temporary episode of neurologic dysfunction
TIA
transient ischemic attack
What causes a hemorrhagic stoke
weakening in the vessel wall due to ateriosclerosis from hypertension
Name the 2 types of hemorragic stroke
- subarachnoid area ( most common)
2. Intracerebral
When diagnosing brain tumors primary vs metastatic, need to first consider what two factos
- Site of neoplasm
2. age of patient
Classification of primary brain tumors depends on which 2 factors?
- Site
2. Histologic composition
Two categories of brain tumors based on histologic type are __ & ____.
Glial and nonglial neoplasms
___ generate from the supporting tissues of the brain and spinal cord.
glial tumors
What is a glioma
Classification
pathology
most common type of brain tumor
Neoplastic
None
what is the most common type of brain tumor
glioma
neoplastic
none
BRAIN Tumors that are highly malignant and occur in young people
Classification:
Pathology
medulloblastoma
neoplastic
none
benign tumor that is slow growing and arises from the acrachnoid tissue
classification
pathology
meningioma
neoplastic
none
what is a meningioma
classification
pathology
exam
benign tumor of the membranes that cover the spinal cord and brain.
*slow growing and arises from the acrachnoid tissue
neoplastic
none
CT
what is the most common nonglial tumor
meningioma
skull thickness surrounding a tumor indicates which tumor
meningioma
benign tumor of pituitary gland
Classification
Pathology
Exam
pituitary adenoma
Neoplastic
None
CT
define pituitary adenoma
Classification
pathology
benign tumor of the pituitary gland
neoplastic
none
radiographic appearance in which there is an enlargment and erosion of the selle turcica is ____
pituitary adenoma
pituitary adenomas may grow out of the ____
selle turcica
If a pituitary adenoma develops before puberty it can result in_____
gigantism
if a pituitary adenoma develops in adults it results in _____
acromegaly
anatomic landmark composed of the middle cerebral artery and its branches
sylvian triangle
define sylvian triangle
anatomic landmark composed of the middle cerebral artery and its branches.
generative brain disorder in which proteins fold upon each other and start to deteriorate the brain
creutzfeldt-jacob disease
