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N 2440 > 12 - Neurological Disequilibrium > Flashcards

12 - Neurological Disequilibrium Flashcards

1
Q

What are the 3 Divisions of the Brain?

A

1) Forebrain
2) Midbrain
3) Hindbrain

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2
Q

What diagnostic Tools are used in Neuro Assessment?

A

1) Medical imaging
- Help visualize structural changes in the brain and spine
- CT scans can detect acute changes (stroke
- MRIS - detailed soft tissue images for tumours or MS

2) Electrophysiological studies
- help assess electrical activity in the brain, muscle, and nerves

3) CSF analysis
- CSF is extracted through a lumbar puncture
- Helps look for signs of infection, inflammation, malignancy

4) Microscopy
- Light and electron - helps to examine tissue biopsies (Imp for tumours)

5) Molecular genetics
- Helps identify genetic mutations and disorders in tumours

6) Biochemical Analysis

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3
Q

Function of the Forebrain

A
  • Largest part of the brain
  • Responsible for high cognitive functioning: thinking, reasoning, voluntary movement
  • includes: frontal, temporal, parietal, occipital lobes, brainstem, and cerebellum
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4
Q

Functions of Structures within the Forebrain

A

1) Frontal lobe
- Reasoning, decision-making, thinking,
- Governs emotions and movement
- Brochas area - responsible for speech production

2) Temporal lobe - just above the ear

3) Parietal - directly above temporal
- Processes sensory information from body (touch, temp)
- Plays tole in speech comprehension

4) Occipital - back of forebrain
- Dedicated to vision

5) Brain stem

6) Cerebellum
- Allows for smooth and coordinate muscle movement

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5
Q

Function of the Midbrain

A
  • involved in vision, hearing, some motor control
  • acts as a conduit for motor and sensory info between brain and spinal cord
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6
Q

Function of the Hindbrain

A
  • Responsible for coordination and balance, and maintains equilibrium
  • Medulla - controls heart rate, BP, and breathing
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7
Q

What are the 4 Types of Cells in the CNS?

A

1) Neurons
- Basic functional units of CNS
- Have a cell body, dendrites, axons
- Initiate and transmit impulses

2) Astrocytes
- Star shaped
- Support growth and nutrition of neurons
- Maintain blood brain barrier
- Regulate blood flow in brain

3) Oligodendrocytes
- Oligodendroglia - made from oligodendrocytes
- Form the myelin sheath around neurons
(Myelin sheath speeds up electrical signal transmission)

4) Microglia
- CNS immune cells; defensive immune response
- Clean up debris and respond to injury and infection

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8
Q

How does the CNS respond to injury/disease?

A

1) Neuronal degeneration
- atrophy, damage or necrosis (death)

2) Axonal degeneration
- axonal swellings or loss

3) Glial reaction
- astrocytic hyperplasia, proliferation → astrocytosis/gliosis (scar formation)

4) Demyelination
- damage to myelin or oligodendrocytes

5) Microglia
- If these proliferate uncontrollable to clear debris, they can cause harm and lead to excessive inflammation and damage

6) Vascular changes
- ischemia (vasculitis and vasospasm)
- vasogenic edema [breakdown of blood brain barrier (BBB)]

7) Cerebral edema - vasogenic - breakdown of BBB with accumulation in extracellular fluid
- cytotoxic (intracellar swellings of neurons and glia e.g. global ischemia)

8) Migration of systemic
- neutrophils, lymphocytes, macrophages migrate into CNS and used to combat injury
- In excess, it worsens inflammation

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9
Q

Functions of the Spinal Cord

A

-located within the vertebral canal
- protected by the vertebral column

FUNCTIONS
1) Connects the brain and the body

2) Conducts somatic and autonomic reflexes

3) Provides motor pattern control centers

4) Modulates sensory and motor function

spinal cord nerves match the location of organs in the region it controls
○ Ex. In cervical spine, you innervate muscles of arm, wrist, and diaphragm

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10
Q

What are the 2 types of tissue within the spinal cord?

A

1) Gray matter - interior
- Central reion
- butterfly shape
- Has neuron cell bodies
- Processes sensory motor information
- Where spinal cord makes connections that allows for reflexes and basic motor control at the level of the spinal cord (ex. Put hand on hot oven, and move it away) not the brain

2) White matter
- Surrounds gray matter
- Myelinated nerve fibres
- Organized into columns
- These fibers from ascending and descending tracks that allows rapid communication bw brain and spinal cord

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11
Q

R VS L Side of Spinal Cord

A
  • Spinal cord consists of ascending and descending tracts that are essential for sensory and motor functioning

L side
- Ascending tracts - carry sensory information - touch, pain temp, from body to brain
- Ascending bc carries sensation from body to brain
- Track allows the brain to process sensation coming rom different parts of body

R side
- Descending - transmits the motor commands from brain down to muscle (voluntary)
- The spinal cord has 2 main types of tissues

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12
Q

Difference bc Upper and Lower Motor Neurons

A

Upper motor neurons
- Completely contained within the CNS
- Control fine motor movement and influence/modify spinal reflex arcs
- Synapse with interneurons; do not directly control muscles, they send signals to interneurons in spinal cord, which communicate with lower neurons which trigger muscle movement
- If damaged (due to stroke), the person can experience spasticity and hyper reflexia - overactive reflexes

Lower motor neurons
- Neurons have direct influence on muscles; lower neurons sends signal to muscle, muscle will contract
- Responsible for voluntary and reflexive muscle movement
- Cell bodies originate in the grey matter of the spinal cord, but their axons extend into the PNS
- if damaged (ALS, spinal cord injures), the person can experience flaccid paralysis, weakness, loss of muscle tone, muscle atrophy, muscle wasting, loss of reflexes (signal to muscle is interrupted)

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13
Q

Protective Structures of the CNS

A

1) Cranium - 8 bones
- protect brain structures
- Galea aponeurotica:
Thick, fibrous band of tissue over the cranium b/w frontal and occipital muscles, adds protection to the skull

2) Meninges
- protective membrane around brain and spinal cord

3) Cerebrospinal fluid (CSF) and the ventricular system

4) Vertebral column (33 vertebrae)
- 7 cervical
- 12 thoracic
- 5 lumbar
- 5 fused sacral
- 4 fused coccygeal

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14
Q

What are the 3 layers of the meninges?

A

1) Dura mater - outermost, toughest layer
- Forms durable covering around the spinal cord

2) Arachnoid - middle layer
- Cusions the brain
- Lies beneath dura

3) Apa mater - innermost layer
- Closely adheres to surface of brain and SC
- Aids in providing blood supply to nervous tissu-

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15
Q

How CSF acts as a protective structure?

A
  • CSF circulates through interconnected spaces - ventricular system (includes ventricle in brain)
  • CSF fills these ventricles cushioning and protecting from injury
  • CSF is produced by networks of blood vessels - choroid plexus (in walls of brain ventricles)
  • BBB and choroid plexus are the filtration system
    - filter blood to create the CSF
    • Process involves removing waste (pathogen and toxins) form the blood and adding substance necessary for brain function
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16
Q

How is the brain supplied blood?

A
  • brain receives 1 L of blood/minute

1) Internal carotid arteries
- provide blood to anterior and middle cerebral arteries
2) Vertebral arteries
- contribute to posterior cerebral arteries

  • carotid and vertebral arteries are connected by a network of arteries at the circle of Willis (base of brain)
  • provides collateral circulation
    ex. If 1 artery is blocked or narrowed other vessels can still supply blood to the brain - reduces the risk of ischemic damage
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17
Q

What is the flow of blood to the brain regulated by?

A
  • Flow of blood to the brain is regulated by CO2 level in the blood
  • When CO2 levels rise, blood vessels in brain dilate to increase blood flow which helps to maintain proper O2 levels and pH balance
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18
Q

What is the Blood Brain Barrier?

A
  • BBB is a highly selective protective mechanism
    ○ Made up of cell structure es that restrict entry of substances from the bloodstream into the brain interstitial space
    ○ Vital for maintain homeostasis by blocking harmful substances (pathogens, toxins)
  • Implications for meds
    ○ Many drugs can not cross the barrier - hard to treat brain infections/ tumours
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19
Q

What is the Peripheral Nervous System Made up of:

A

1) Spinal Nerves - 31 pairs
- mixed nerves - have sensory and motor fibres in it

2) Cranial Nerves - 12 pairs
- Emerge from the brainstem
- Some control smell and vision
- Others control motor movements like eye movement and facial expression

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20
Q

What are the 12 Pairs of Cranial Nerves

A

1) Olfactory - responsible for smell

2) Optic - responsible for vision

3) Oculomotor - controls eye movement and eyelid elevation

4) Trochlear - controls oblique muscle of eye; helps rotate it down and laterally

5) Trigeminal - provides sensation to te face and controls muscle for chewing

6) Abducens - controls lateral rectus muscle which moves eye up

7) Facial - controls facial expressions taste sensation in parts of tongue

8) Vestibulocochlear - responsible for hearing and balance

9) Glossopharyngeal - involved in taste from posterior 1/3 of tongue and swallowing

10) Vagus - regulates autonomic function; hear rate, digestion, RR

11) Accessory - controls sternocleidomastal and trapezius muscle (turning and looking ver shoulder, muscle that pops up

12) Hypoglossal - controls tongue movement imp for speech and swallowig

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21
Q

Nervous System Disorders

A

1) Neoplasma
- meningiomas
- spinal cord tumours

2) Infections
- brain and spinal abscess
- encephalitis

3) Vascular Disorders
- cerebral vascular accident
- non-traumatic hemorrhage
- hypertension hemorrhage

4) Trauma
- focal/diffuse brain injury
- spinal cord injury

5) Neurodegenerative
- dementia
- Alzheimer

6) Demyelinating
- MS
- Guillan-Barre

22
Q

What are Neoplasms?

A
  • brain tumours
    3 Types

1) Primary - Originate in the brain (gliomas)
- Gliomas - tumours that arise from glial cells
a) astrocytes
b) Oligodendroglioma
c) Ependymoma
- Extracerebral - form outside of the brain (type of primary)
ex. meningioma

2) Metastatic (more common)
- Secondary tumours that spread to brain from other parts of the body

23
Q

What are Meningiomas?

A
  • Tumours that arise from meninges
  • Dome shaped, sits on dura
  • found in middle to old age
  • often benign
  • Often cured by surgery
  • characteristic feature: whorl pattern
  • can lead to neurological damage due to pressure on the brain
24
Q

What are the 2 types of Spinal Cord Tumours?

A

Classified based on location relative to spinal cord

1) Intramedullary - within spinal cord tissues
ex. Gliomas - most common

2) Extramedullary - outside spinal cord but still within spinal canal
- Categorized into:
- Intradural - inside dura mater (outside spinal cord)
- Extradural - outside dura

25
Q

What are the manifestations of Spinal Cord Tumours?

A

1) Compressive Syndrome - tumours compress spinal cord
S: pain, muscle weakness, sensory loss or paralysis

2) Irritative Syndrome - the tumour can irritate spinal cord
S: pain, spasticity

26
Q

What causes a CNS infection?

A

1) Bacteria
- Bacterial infections are marked by increased presence of neutrophils in CSF
- Common symptoms: fever, neck stiffness, headache, confusion

2) Viruses
- Viral infections leads to increase in lymphocytes in CSF

3) Fungi
- Fungal infections tend to be seen in immunocompromised patients

27
Q

What is Brain and Spinal Abscess?

A
  • Due to infection
  • Localized collection of pus within the parenchyma
  • Can be found in different locations:
    ○ extradural - outside
    dura
    ○ Subdural - bw dura and
    arachnoid
    ○ Intracerebral - within
    brain tissue
  • Infection begins with localized inflammation but can evolve into necrotic core quickly
28
Q

Clinical Manifestations in Brain Vs. Spinal Abscess

A

Brain
Early: low-grade fever, headache (most common), neck pain and stiffness, confusion, drowsiness, sensory deficits, and communication deficits

Later: inattentiveness (distractibility), memory deficits, decreased visual acuity and narrowed visual fields, papilledema, ocular palsy, ataxia, seizures, and dementia

Spinal
- Spinal aching- earliest symptoms

  • Severe root pain, accompanied by spasms of the back muscles and limited vertebral movement
  • Weakness caused by progressive cord compression
  • Paralysis
29
Q

What is Encephalitis?

A
  • Acute, severe illness arising from viral infection
  • common symptoms: Headache, Fever, Seizure, Loss of consciousness
  • infection can spread to brain in 3 ways

1) Direct (most common)
- virus causes encephalitis by entering brain through direct spread from nearby infections (ear, sinus infxns)

2) Hematogenous
- spread through bloodstream
- from lungs, congenital heart disease, bacterial endocarditis

3) Trauma or medical procedures

30
Q

What is the most common vascular disorder of the CNS?

A

STROKE
- rapid onset of clinical signs showing disturbance in cerebral function w/ symptoms lasting > 24 hrs

Stroke can be classified into different categories
1) Ischemic - blockage of blood flow to the brain
- Blockage can be from different sources
□ thrombotic (blockage is from blood clot)
□ Emboli - clot is formed elsewhere and migrates to brain

2) Hemorrhage - occurs when there is bleeding in/around the brain due to the rupture of a blood vessel

3) Hemodynamic - from inadequate blood flow due to drop in BP

31
Q

What is a Cerebral Vascular Accident?

A

Cerebral infarct - the area of the brain that has been blocked of blood vessels
○ Area of tissue necrosis that results from no longer having sufficient blood supply
○ Common due to occlusions in cerebral, vertebral, and internal carotid arteries

2 Causes of Vascular Occlusion
1) Thrombosis (within brain)- blood clot that blocks blood flow
- due to:
1. atherosclerosis - lipid deposit buildup in arteries in sites where carotid arteries sperate

  1. vasculitis - inflamed blood vessels which causes narrowing, so if there is an obstruction, it gest stuck there

2) Emboli
- blood clots formed elsewhere in body
□ Could have Vegetations - pieces of material from infected areas
□ Atherosclerotic plaques
□ Other causes of emboli: air, fat, neoplastic cells

Manifestations
1) Transient Ischemic Attack
- symptoms arise suddenly and subside w/i 24 hours

2) Stroke

32
Q

What are the 2 types of Non-Traumatic Haemorrhage

A

1) Intracerebral - brain bleed that occurs within brain tissues itself
○ Can be caused by underlying conditions
- Hypertension
- Vascular malformation
- Ruptured aneurism
○ Leads to rapid neurological deterioration

2) Subarachnoid - Blood accumulates between brain and thin tissues covering it
- Most common cause is saccular aneurism - congenital weakness in blood vessel
- Can be caused by vasculitis which can be immune-mediated from pathogen or non-septic or by inflammatory conditions
- Presents with sudden, severe headache

33
Q

What is a Hypertension Hemorrhage?

A
  • Occurs due to chronic high BP
  • high BP leads to arteriosclerotic changes in small blood vessels of the brain
    ○ Overtime, the vessels become weak and can cause micro aneurysms
    ○ These are prone to rupturing

Common Sites: basal ganglia and thalamus

Treatment: reduce incidence
- fatal, if untreated

34
Q

What are Traumatic CNS Disorders

A

Traumatic Brain Injury

Mechanisms of TBI
○ Impact/blunt force - direct blow to head causing tissue damage

○ Acceleration /deceleration - typically seen in whiplash  where brain moves rapidly within skull causes stretching and tearing of blood vessels and neurons 

○ Penetrating/missal - when object (bullet, knife) eneters brain and causes direct damage to tissue
 
○ Blast injury - brain has shockwave that causes diffuse axonal injuries

2 Types of TBI
1) Focal
- Localized to specific region of the brain (from contusion or hematoma)

2) Diffuse
- Involve widespread damage across different areas of the brain
□ Ex. diffuse axonal injuries - brain cells are stretched and damage due to rapid acceleration and deceleration

35
Q

What is A Focal (local) Brain Injury

A
  • Refers to observable damage in specific region of the brain
  • impact often produces contusions or bruising and localized damage
36
Q

What is A Closed Brain Injury

A
  • if you do not break the skull, and dura mater is undamaged
  • Brain is not exposed to external environment
  • causes focal or diffuse injury
37
Q

What are the effects of a Focal Closed Brain Injury?

A

1) Coup - injuries which occur directly below the point of impact
○ Where the brain is bruised or compressed at the site where the force was applied
○ Result of brain moving against the skull and hitting it when it gets struck

2) Contrecoup - occurs on side opposite from impact
○ After brain was initially displaced by original impact, it slams against opposite side of skull causing damage at that location
○ common in deceleration/ acceleration incidents (whiplash)

  • coup and countercoup cause brain to shake and axons of neurons shear, so neuron get broken
    ○ Destroyed neurons means no synapses are occurring = neurological impairment
  • contusions can cause hematoma’s in different areas
    ex. subdural hematoma - under dura, epidural - outside dura
38
Q

What are the typses of Hematoma?

A

Hematomas - collection of blood within the brain tissue from a focal injury

1) epidural; above dura mater
○ Results from blunt force trauma (skull fracture) that can cause damage to an artery (middle meningeal artery) which leads to accumulation of blood between dura and skull
○ Can cause rapid neurological deterioration if pressure is not relieved on the brain

2) Subdural hematomas - beneath dura mater
○ In space between dura and brain
○ Caused by venous bleeding resulting from tear in bridging veins that connect from brain surface to venous sinuses
○ Develops more slowly than epidural
○ Symptoms evolve over hours/days
○ Common in elderly who sustain head trauma

3) Subarachnoid - beneath arachnoid matter
○ Result from trauma or ruptured aneurysm
○ Can cause bleeding into the CSF
○ Can cause severe headache, nausea, and neuro deficits

4) Intracerebral hematomas - bleeding within brain itself
○ Can be from traumatic brain injury or hypertension or tumours

39
Q

What is an Open Focal Brain Injury

A
  • Injury breaks the dura and exposes the cranial contents to the environment
  • broken dura increases risk of infection and further damage bc of the brains vulnerability
  • Causes both focal and diffuse injuries

Treatment: surgery
- Remove foreign object
- Repair damages tissue

40
Q

What is a Diffuse Brain Injury?

A
  • occurs when there is acceleration or decelerating or rotational forces that cause widespread damage to brains axons
  • Forces lead to shearing, tearing, or stretching of axons which disrupts the communication bw neurons and causes dysfunction
  • Severity corresponds to the amount of shearing force applied to the brainstem

1) Concussion - brief disruption of brain function with no significant structural damage to brain
□ Symptoms: confusion, dizziness, memory loss (resolves within minutes/hours
□ Post concussive syndrome - where individual have symptoms over long period of time without structural damage on brain
□ If a concussion causes structural damage, it would be considered mild traumatic brain injury

2) Mild
□ Involves subtle neurological deficits
□ Moderate and severe
□ Ex. LOC, coma, sensory and motor deficits,

3) Severe
□ Permanent brain damage, vegetative state, death

  • Diffuse axonal injury is difficult to detect on standard imaging (CT, MRI) bc damage is microscopic and widespread -
41
Q

Difference bw Primary and Secondary Spinal Cord Injury

A

Primary - immediate damage to spinal cord that happens at the time of mechanical trauma
○ Damage can be due to dislocation, blunt force trauma, vertebral fracture
○ directly causes destruction of spinal cord tissues
○ Can occur without visible vertebral fracture or dislocation

Secondary - pathophysiological cascade of events that begins immediately after primary injury (lasts for weeks)
○ further compromises the spinal cord by reducing blood flow ad oxygen to the area which worsens tissue injury and there is further loss of function
○ Life threatening if swelling is in cervical region
- C3 AND C4, C5 keep the diaphragm working which allows us to breathe - swelling in this area can compress resp center and lead to resp failure, paralysis, and death

42
Q

What is a Vertebral Injury?

A

Types of injuries
1) Simple fracture - straightforward break in vertebral bone
- May or may ot affect surrounding structures

2) Compressed/wedged
- Occurs when vertebra is compressed casing is to collapse or wedge in shape
- Narrows the spinal canal which impinges the neurons in that area

3) Comminuted/burst
- Occurs when vertebra shatters into multiple fragments
- Causes disruption in surrounding tissues bc bone fragments have potential to migrate into spinal cord

4) Dislocation - misalignment of vertebra which can stretch or compress spinal nerve-

43
Q

Clinical Manifestations of Spinal Cord Injury

A
  • Severity relates to how complete the spinal cord has been severed

1) Spinal shock
○ happens early on
○ Causes temporary loss of spinal cord activity below
○ Can lead to loss of reflux function ( bladder, bowel, skeletal and autonomic function)

2) Neurogenic Shock
○ Happens with injuries above the T5
○ Caused by disruption of sympathetic nervous system
○ Leads to low BP, slow heart rate, poor organ perfusion
○ Requires urgent treatment to stabilize the CV system

3) Autonomic hyperreflexia
○ Life threatening
○ Occurs in ppl with spinal cord injures at or above T6
○ uncompensated cardiovascular response to stimulation of SNS
○ Stimulation of the sensory receptors below the level of the lesion
○ Can cause severe HPTN, bradycardia, and lead to stroke or seizures if not treated quickly

44
Q

How does Autonomic Dysreflexia/Hyperreflexia Occur?

A

1) Noxious stimulus - having a full bladder or from bowel

2) Sends afferent stimulus ands nerve go through ascending track
- If you have spina cord injury, and you don’t have the complete tract, the message may not be relayed to the brain

3) The brain does not understand, so it produces a massive sympathetic response that is uncontrolled

4) Leads to widespread vasoconstriction

5) Vasoconstriction leads to hptn

6) Baroreceptors in the brain detect a hypertensive crisis

7) signals to slow the HR and the motor/ descending pathways is disrupted/blocked
- There is a continuous signal to change something in the body but it never gets to the brain and then the brain is also trying to release motor commands but it can not get to the point before the level of injury to make a difference

45
Q

What are Neurodegenerative Disorders?

A
  • Involve progressive death of neurons
  • Associated with accumulation of proteins within neurons, glial cells, or extracellular space
  • Types are classified on clinical manifestations

1) Cortical degeneration
- Affects cognitive function and behaviour

2) Movement
- Affects motor control
- Symptoms: tremors, involuntary movement, rigidity

3) Motor neuron
- Degeneration of motor neurons
- Leads to muscle weakness, paralysis, and death

46
Q

What is Dementia?

A

Dementia - progressive decline in many cerebral functions (esp those impairing intellectual processes)

Losses
○ Orientation
○ Memory - mostly short-term
○ Language - difficulty finding words or understanding speech
○ Judgement - lose ability to judge
○ Decision making

Mechanisms of Dementia
1) Neuron degeneration - loss of nerve cells

2) Brain tissue compression - can be from tumours compressing the brain

3) Atherosclerosis

4) Brain trauma

47
Q

What is Alzheimer Disease?

A
  • Most common cause of dementia
  • Has 2 types
    1) Early-onset familial
    • Rare form
    • Occurs before age 65
    • Inherited with strong genetic links

2) Non hereditary
- Late onset
- Sporadic
- More common form
- Influenced by combination of genetic, environmental, and lifestyle factors

Manifestations:
- Forgetfulness
- Emotional upset
- Disorientation
- Confusion
- Lack of concentration
- Decline in abstraction, problem solving, and judgement

48
Q

What are the 2 theories for how it is caused?

A

1) Mutation in amyloid
- The mutation leads to accumulation of amyloid plaques in brain
- Plaques disrupt communication bw neurons and cause cell death

2) Apolipo E
- Involve din lipid metabolism
- Variants of the gene - apo E4 increases risk of Alzheimer’s
- Promotes amyloid plaque formation and neurodegeneration

49
Q

What are the 2 hallmark features for Alzheimer’s in brain scans?

A

1) Neurofibrillary tangles - twits fibres of a protein called tao
- accumulates inside neurons
- Tangles disrupt electrical conductivity of the neuron impairing its function and eventually causing cell death

2) Senile plaques
- Consists of beta-amyloid protein
- Their deposits accumulate outside of neurons
- Block communication bw nerve cells which triggers inflammation and further damages the brain

50
Q

What is Frontotemporal Dementia?

A
  • 2nd most common form
  • age of onset > 60 (same age as early onset Alzheimer’s but diff clinical features)
  • Leads to progressive nerve death, in frontal and temporal lobe tissue - responsible for higher cognitive functions related to behaviour and emotional regulation
  • runs in families
  • changes mainly affect PERSONALITY (change in behaviour, impulsivity)
51
Q

What is Multiple sclerosis (MS)?

A
  • Chronic autoimmune disorders
  • Body’s immune system mistakenly attacks myelin sheath
  • Causes inflammation and damage to oligodendrocytes - responsible for producing and maintaining the myelin
    ○ As myelin is lost, nerve conduction is disrupted = impairment
  • Onset: bw 20 and 40 yrs
  • Exact cause is unknown; could have genetic or environmental influence
  • 4 subtypes; ppl can transition bw them
  • Common symptoms: paraesthesia -abnormal sensation or tingling, numbness, unilateral limb weakness, visual disturbance (optic neurosis - inflammation of topic nerve), difficulty with gait and coordination, dysarthria (speech difficulty)
    ○ Intellectual function remains unaffected
  • NO CURE
52
Q

Guillain-Barré syndrome

A
  • Results in demyelination of peripheral nerves
  • Has potential to rapidly progress and cause ascending motor paralysis
  • Demyelination disrupts normal electrical concavity
    ○ Leads to muscle weakness, paresthesia, paralysis or death
    ○ Ascending paralysis - begins in legs, progresses up to involving arms, trunk, and resp muscle, resp failure (severe)
  • recovery can take from months - 2 years

N 2440 (26 decks)

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