Neurologic System Flashcards
1
Q
What are the (3) types of pain?
A
Somatic
Visceral
Neuropathic
2
Q
Somatic Pain
A
caused by the activation of pain receptors in either the body surface or musculoskeletal tissues
*common cause of somatic pain in SCI persons is postsurgical pain from the surgical incision
3
Q
Visceral Pain
A
is the pain we feel when our internal organs are damaged or injured and is by far the most common form of pain
4
Q
Neuropathic Pain
A
caused by injury or malfunction to the spinal cord and peripheral nerves. Neuropathic pain is typically a burning, tingling, shooting, stinging, or “pins and needles” sensation
5
Q
What are nociceptors?
Where are they located in each of the 3 areas of pain?
A
The nociceptors (free nerve endings) are distributed in the:
somatic structures (skin, muscles, connective tissue, bones, joints);
visceral structures (visceral organs such as liver, gastro-intestinal tract).
Nociceptors transmit impulses to the brain via C fibers and A-delta fibers.
6
Q
What s the Pain pathway?
A
Transmission
Perception
Modulation
7
Q
Pain Transmission
A
- Noxious stimulus occurs
- impulse travels via A-delta or C fibers to the dorsal horn of the spinal cord.
- Impulse ascends to the thalamus, brain stem, and cerebral cortex for processing and interpretation.
8
Q
Pain Perception
A
Interpretation influenced by cultural preferences, male/female, life experience both past and present; location, character, location, and intensity
learned behaviors regarding pain.
9
Q
Pain Modulation
A
Mechanisms that increase or decrease transmission of pain signals within the system (either before, during, or after the pain is perceived).
Endogenous opioids such as endorphins can block the transmission of pain impulses to decrease the perception of pain.
Endorphin receptors are located close to known pain receptors in the periphery and ascending and descending pain pathways.
10
Q
What are the (2) main classifications of pain?
A
Acute & Chronic
11
Q
What is the normal range of body temperatures?
A
- 2 - 37.7 C
96. 2 - 99.4 F
12
Q
When should a fever be treated?
A
When it causes serious side effects, such as cardiovascular stress, nerve damage, brain damage, or convulsions
13
Q
Heat cramps
A
severe, spasmodic cramps in the abdomen and extremities; follow prolonged sweating (due to loss of sodium); signs include fever, rapid pulse rate, and increased blood pressure
14
Q
Heat exhaustion
A
- due to prolonged high core or environmental temperatures
- profound vasodilation and profuse sweating
- dehydration, decreased plasma volume, hypotension, decreased cardiac output, and tachycardia; symptoms include weakness, dizziness, confusion, nausea, and fainting
15
Q
Heat Stroke
A
when the core temperature rises high, the regulatory center stops working and the body’s mechanisms for heat loss fail;
symptoms = high core temperature, ABSENCE of sweating, rapid pulse, confusion, agitation, and coma.
Complications = cerebral edema, degeneration of the CNS, renal tubular necrosis, and liver failure…delirium, coma, and eventual death is not corrected.
can be lethal
16
Q
Malignant hyperthermia
A
rare muscle disorder that can become a complication of surgery. It is triggered by inhaled anesthetics and depolarizing muscle relaxants
Can be fatal
- Calcium function in the muscle cells becomes altered causing hypermetabolism, muscle contraction
- increases the work of the muscleincreasing oxygen consumption and increases lactic acid production
- acidosis develops, body temperature rises rapidly. The patient becomes tachycardic with dysrhythmias, hypotensive, decreased cardiac output, and eventually will progress to cardiac arrest.
Signs resemble those of coma= unconsciousness, absent reflexes, fixed pupils, apnea.
17
Q
What are the (4) mechanism of heat loss?
A
Radiation
Conduction
Convection
Evaporation
18
Q
Radiation
A
heat loss through waves emanating from surfaces with temperature higher than the surrounding air
19
Q
Conduction
A
heat loss though direct touch from one surface to another, so that warmer surface loses heat to cooler surface
20
Q
Convection
A
heat loss through currents of gases or liquids; exchanges warmer air at body’s surface with cooler air in surrounding space
21
Q
Evaporation
A
Body water evaporates from surface of skin and from mucous membranes; sweating promotes heat loss
22
Q
Body’s response mechanisms to hypothermia:
“S.H.I.P”
A
- Stupor; heart rate and respiratory rates decline, cardiac output diminishes; metabolic rate falls; acidosis; eventual cardiac dysrhythmias and asystole
- Hypothalamus induces shivering
- Intermittent reperfusion of extremities (aka, Lewis phenomenon)
- Peripheral vasoconstriction
23
Q
Describe the Sleep Cycle
A
Stage 1: drowsiness
Stage 2: period of light sleep (heart rate slows, brain does less complicated tasks)
Stages 3 & 4: deep sleep known as slow-wave or delta sleep (body makes repairs; body temperature and BP decrease)
Stage 5: rapid eye movement or REM characterized by intense dreams (increase in-eye movement, heart rate, breathing, BP and temperature)
24
Q
Sleep Deprivation
A
can cause CNS symptoms, impair the immune system and put the person at risk for disease (including diabetes type 2 and heart disease),
decrease reactions times, cause chronic pain, growth suppression, risk for obesity, and decreased body temperature.
25
Glaucoma
intraocular pressure (>12-20 mmHg)
loss of acuity from pressure on the optic nerve causing optic nerve fibers to die
26
Glaucoma: Open Angle
obstruction of the outflow tract causing a build up of aqueous humor
a leading cause of blindness; few symptoms to alert the patient
27
Glaucoma: Angle Closure
displacement of the iris toward the cornea causing an obstruction of aqueous humor outflow
causes sudden rise in intraocular pressure, pain, and visual disturbance
28
Glaucoma: Congenital Closure
rare disease associated with congenital malformation and other genetic anomalies
29
What is ARMD?
Age Related Macular Degeneration
A - Age
R - Retinal Vein Occlusion
M - Myopia (nearsightedness)
D - Diabetes mellitus
30
Compare WET vs. DRY ARMD
Dry=nonexudative; slow progressive with drusen (waste products) in the retina
-limits night vision and causes difficulty reading
Wet=exudative; accumulation of drusen, abnormal blood vessels, leaking of blood or serum, retinal detachment, scarring, loss of photorecptors, and severe loss of central vision
31
The retina detaches from where it SITS. What does this acronym stand for?
S - Secondary to some intra-ocular problem such as with glaucoma or with a tumor
I - Idiopathic
T - Traumatic
S - Surgery for cataract
32
Symptoms of Retinal Detachment
| Remember 3 F's
Falling acuity
Floaters
Flashes (migraine)
33
General definition of Conjunctivitis
an inflammation of the conjunctiva caused by bacteria, viruses, allergies, or chemical irritants.
34
Viral conjunctivitis
Watery, itchy eyes; sensitivity to light.
One or both eyes can be affected
Highly contagious; can be spread by coughing and sneezing
35
Bacterial conjunctivitis
A sticky, yellow or greenish-yellow eye discharge in the corner of the eye.
In some cases, this discharge can be severe enough to cause the eyelids to be stuck together when the person wakes up.
One or both eyes can be affected.
Contagious (usually by direct contact with infected hands or items that have touched the eye)
36
Allergic conjunctivitis
Watery, burning, itchy eyes; often accompanied by stuffiness and a runny nose, and light sensitivity Both eyes are affected. Not contagious
37
Trachoma
(Chlamydial conjunctivitis) results from the sexually transmitted infection Chlamydia trachomatis
often associated with poor hygiene or an infant born vaginally to an affected mother
38
Strabismus
one eye deviates from the other when the person is looking at an object.
caused by weak or hypertonic muscle in one eye.
deviation may be upward, downward, inward, or outward.
In children strabismus requires rapid intervention to preserve vision in the affected eye
39
Nystagmus
an involuntary unilateral or bilateral rhythmic movement of the eyes
It may be present at rest or when the eye moves
may be regular or jerky movement
may be caused by an imbalanced reflex activity of the inner ear or can be cause by irregularities of some of the cranial nerves
40
Amblyopia
reduced vision in an eye caused by cerebral blockage of the visual stimuli
41
Scomata
a defect of the central field of vision
42
Cataracts
cloudy or opaque areas in the ocular lens
The incidence increases with age
most commonly it is a result of degeneration
43
Papilledema
edema and inflammation of the optic nerve where it enters the eyeball
caused by obstruction of venous return from the retina due to either increased intracranial pressure, retrobulbar neuritis, or changes in retinal blood vessels
44
Presbyopia
(happens with advancing age)
the loss of accommodation in which the ocular lens becomes larger, firmer, and less elastic.
reduced near vision, causing the individual to hold reading materials at arm’s length
45
Myopia
nearsightedness: light rays are focused in front of the retina when the person is looking at a distant object
46
Hyperopia
farsightedness: light rays are focused behind the retina when a person is looking at a near object
47
Astigmatism
unequal curvature of the cornea: light rays are bent unevenly and do not come to a single focus on the retina.
may coexist with myopia, hyperopia, or presbyopia
48
Conductive hearing loss
possible causes?
occurs when sound is not conducted efficiently through the outer ear canal to the eardrum and the tiny bones (ossicles) of the middle ear.
usually involves a reduction in sound level or the ability to hear faint sounds.
can often be corrected medically or surgically
Possible Causes:
Benign tumors
Impacted earwax (cerumen)
Infection in the ear canal (external otitis)
Swimmer’s ear (otitis externa)
Presence of a foreign body
Absence or malformation of the outer ear, ear canal, or middle ear
49
Sensorineural hearing loss
Possible causes?
(SNHL) occurs when there is damage to the inner (cochlear hair cells), or to the nerve pathways from the inner ear to the brain.
cannot be medically or surgically corrected (mostly).
most common type of permanent hearing loss.
reduces the ability to hear faint sounds.
Even when speech is loud enough to hear, it may still be unclear or sound muffled.
```
Possible causes of SNHL:
Illnesses
Drugs that are toxic to hearing
Hearing loss that runs in the family (genetic or hereditary)
Aging
Head trauma
Malformation of the inner ear
Exposure to loud noise
```
50
Acute Otitis Media vs. Otitis Media w/ effusions
Acute otitis media=infection
-associated with ear pain, fever, irritability, inflamed tympanic membrane, and fluid in the middle ear.
Otitis media with effusions=no infection
-presence of fluid in the middle ear without symptoms of acute infection
51
What are the (5) categories of neurologic function?
1. Level of consciousness
2. Pattern of breathing
3. Pupillary reaction
4. Oculomotor responses
5. Motor responses
52
Abnormal breathing patterns such as Cheyne-Stokes respirations indicate __________ or coma.
brain dysfunction
53
What are the different Levels of Altered Consciousness?
Acronym for the LOC?
A - Alert
V - Verbal Stimuli
P - Painful Stimuli
U - Unresponsive
```
Confusion
Disorientation
Lethargy
Obtundation
Stupor
Coma
Light coma
Deep coma
```
54
Brain death
the whole brain is damaged to the point that it can never recover or maintain the body’s internal homeostatis
1. All appropriate diagnostics and therapeutic procedures have been done with no possibility for the brain to recover function.
2. Unresponsive coma
(no motor or reflex movements).
3. No spontaneous respirations (apnea)
4. No brain stem function
(pupils fixed, dilated; no gag or corneal reflex)
5. Flat EEG
Persistence of these signs for an appropriate observation period.
55
Cerebral death
(irreversible coma) death of the cerebral hemispheres except for the brain stem and cerebellum
The brain stem may be able to maintain body temperature, cardiovascular function, respiration, and metabolic functions.
56
Persistent vegetative state
complete unawareness of self, surroundings, and complete loss of cognitive function
57
Minimally conscious state
may follow simple commands, manipulate objects, gesture or give yes/no responses, have intelligible speech, and have movements such as blinking or smiling
58
Locked-in syndrome
compete paralysis of voluntary muscles with the exception of eye movement
thought and level of arousal are intact
has full cognitive abilities
cannot communicate through speech or body movement
59
Partial seizures (Focal seizures)
Partial seizures may be divided into:
simple and complex seizures
simple seizures = cause no interruption to consciousness
complex seizures = interrupt consciousness to varying degrees.
60
Generalized seizures: Primarily generalized seizures can be sub-classified into a number of categories, depending on their behavioral effects:
```
Atonic
Tonic-Clonic
Clonic
Myoclonic
Absence
```
61
Generalized Seizures: Atonic seizures
involve the loss of muscle tone, causing the person to fall to the ground
sometimes called 'drop attacks' but should be distinguished from similar looking attacks that may occur in narcolepsy or cataplexy.
62
Generalized Seizures: Tonic–clonic seizures
(Grand mal): involve an initial contraction of the muscles (tonic phase) which may involve tongue biting, urinary incontinence and the absence of breathing
followed by rhythmic muscle contractions (clonic phase). This type of seizure is usually what is referred to when the term 'epileptic fit' is used colloquially.
63
Generalized Seizures: Clonic seizures
myoclonus that are regularly repeating at a rate typically of 2-3 per second
64
Generalized Seizures: Myoclonic seizures
involve an extremely brief (< 0.1 second) muscle contraction and can result in jerky movements of muscles or muscle groups.
65
Generalized Seizures: Absence seizures
(Petit mal): involve an interruption to consciousness where the person experiencing the seizure seems to become vacant and unresponsive for a short period of time (usually up to 30 seconds).
Slight muscle twitching may occur...classified as:
1 Typical absence seizures
2 Atypical absence seizures
66
Agnosia
failure to recognize the form and nature of objects…a defect in pattern of recognition.
May not can identify an object by touch but can by sight.
67
Dysphasia
impaired comprehension or production of language
68
Dementia
progressive failure of cerebral functions that may result in decreased orientation, memory, language, judgment, and decision making
may also be alterations in behavior
69
What are the (5) A's to Alzheimer's?
Anomia - inability to remember names of things
Apraxia - misuse of object due to misidentification
Agnosia - inability to recognize familiar things
Amnesia - memory loss
Aphasia - inability to express via speech
70
Describe the steps leading up to an Alzheimer's diagnosis:
1. Amyloid proteins are not cleared as they should be and accumulate into plaques
2. disruption of nerve impulse tranmission and nerve death.
3. Dead nerves for neurofibrillary tangles.
4. Loss of cholinergic neurons also means a loss of acetylcholine (their neurotransmitter)
5. decline of memory and attention
71
Vasogenic edema
increased capillary permeability in the brain after injury to the vascular structure
blood brain barrier is disrupted and plasma proteins leak into the extracellular spaces, drawing water with them
starts in the area of injury and spreads with fluid accumulating.
Edema promotes more edema because of the ischemia from the pressure of the fluid
72
Cytotoxic (metabolic) edema
toxic agents from inside cells disrupt the active transport system
1. cells lose potassium and gain a larger amount of sodium
2. water follows sodium by osmosis into the cells
3. cell swells (happens mostly in the gray matter)
73
Interstitial edema
movement of fluid from the ventricles in the brain to the extracellular space due to increased hydrostatic pressure.
Seen most often with noncommunicating hydrocephalus (happens mostly in white matter)
74
What is the relationship w/ Basal Ganglia, Cerebral Cortex and neurons in Huntington disease?
involves the basal ganglia and cerebral cortex
Chorea
The neurons that are lost contain gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter…so loss of neurons=loss of GABA and thus the loss of inhibition of movement
75
List some of the symptoms of Huntington's Disease:
```
slow progression
Involuntary, fragmented movements
Irregular, uncontrolled movements
Dementia
Loss of working memory and reduced capacity to plan, organize, and sequence
Thinking is slow
Restlessness, disinhibition (not able to inhibit oneself from things that are not social acceptable) and irritability are common
Euphoria or depression may be present
```
unusual body movements (dancelike movements)
Inherited (autosomal dominant trait)
76
Parkinson’s disease is due to ...
degeneration of the basal ganglia and loss of dopamine (an inhibitory neurotransmitter) producing neurons.
With the loss of dopamine, there becomes a relative excess of cholinergic (excitatory activity)
hypertonia (tremor and rigidity)
akinesia=abnormal movement
77
Clinical manifestations of Parkinson's disease:
```
Tremor at rest
Rigidity (muscle stiffness)
Bradykinesia/akinesia
Postural disturbance
Dysarthria
Dysphagia
Symptoms are always bilateral but may be unilateral in the early stages
Early in the disease process reflexes, sensory, and mental status are usually normal.
As the disease progresses….
Postural abnormalities (flexed, forward leaning)
Difficulty walking
Weakness
Speech slurring
Inappropriate diaphoresis
Orthostatic hypotension
Drooling
Gastric retention
Constipation
Urinary retention
Depression
```
78
Concussion
the brain function disrupts temporarily
may cause unconsciousness that is often short-lived, and is followed by headache, ringing in ears, dizziness, nausea, and tiredness.
***People playing sports like soccer, football, and rugby, commonly suffer from concussions that are considered to be the least-severe form of brain injury.
79
Contusion:
formation of bruise in the brain tissue.
typically cause structural brain damage, in which blood leaks from broken blood vessels.
This results in hematoma-pooling of blood around the brain tissue.
Contusions, considered to be MORE SEVERE than concussions, reduce oxygen flow to the brain
80
Hematomas
hemorrhaging into the brain
can develop immediately or slowly
named according to the location
1. epidural-bleeding between the dura and the skull
2. subdural-bleeding between the dura and acachoid
3. subarachnoid-bleeding in the space between the arachnoid and pia
4. intracerebral-bleeding in the brain tissue itself)
81
Coup-Contrecoup Injury
the damage does not remain restricted at the site of impact
Injury also occurs at the opposite side of the area of the brain that was affected in the injury. Thus, contusion develops not only at the impacted site, but also in the region opposite to the site of injury...the head blow is so severe that the brain shifts and hits the opposite side of the skull, causing another contusion to form within the brain
82
Diffuse Axonal Injury (DAI)
the damage does not remain confined to a particular area, but affects a major part of the brain.
DAI occurring from high speed vehicle accidents, causes the brain to shake violently and rapidly within the bony skull, resulting in widespread damage to the nerve tissue of the brain.
most cases of diffuse axonal injury result in coma, with majority of patients failing to recover from this state of unresponsiveness. Those who regain consciousness tend to suffer from lifelong cognitive impairments.
in over 90% of cases, the patient appears in a continuous vegetative state.
83
Shaken baby syndrome
a type of DAI (Diffuse Axonal Injury) that occurs when an infant under 2 years of age is shaken too fast and repeatedly.
This violent shaking of the head causes the brain to move back and forth within the skull...eventually leading to DAI.
84
Penetrating Injury
The impact of the external force is so strong that the object pierces through the skull and reaches the brain.
This is the most severe form of brain injury that often results from gunshots or when assaulted with a sharp weapon.
85
Increased intracranial pressure
describes increased volume in the limited space of the cranial cavity.
The volume capacity inside the skull is fixed in adults
-normal ICP=60-200 mm H2O or 4-15 mmHG.
There are compensatory mechanisms for transient increases in ICP such as position changes, coughing, or sneezing
86
Herniation
a possible complication of ICP.
the displacement of the brain tissue.
can cause impaired blood flow to brain tissues or pressure on brain tissues
can eventually cause death
87
Decorticate Posturing
(flexor)
Arms are like C's - moves in toward the cord
Problems with cervical spinal tract or
Cerebral Hemisphere
88
Decerebrate Posturing
(extensor)
Arms are like E's
Problems w/in Midbrain or Pons
89
Spinal Cord Injury: Cord contusion
bruising of the neural tissue, swelling, and temporary loss of cord functions
90
Spinal Cord Injury: Cord compression
pressure on the cord causing ischemia to tissues;
must be relieved to prevent permanent damage to the spinal cord
91
Spinal Cord Injury: Laceration
tearing of neural tissues in the spinal cord;
may be reversible if only slight damage is done;
may result in permanent loss of cord function is the spinal tracts are disrupted
92
Spinal Cord Injury: Transection
severing of the spinal cord that results in permanent loss of function
Complete=all tracts are disrupted
Incomplete=some tracts remain intact; may have some recovery
93
Paresis vs. Paralysis
Paresis=weakness or partial paralysis with incomplete loss of muscle power.
Paralysis=loss of motor function so that a muscle group is unable to overcome gravity.
94
Hemiparesis vs. Paraparesis vs. Quadraparesis
Hemiparesis/hemiplegia=paresis/paralysis of the upper and lower extremities on one side.
Paraparesis/paraplegia=paresis/paralysis of the lower extremities
Quadriparesis/quadriplegia=paresis/paralysis of all four extremities.
95
What are the Classifications of spinal cord trauma?
Hyperextension
Hyperflexion
Vertical Compression
Rotation Forces
96
Spinal Cord Trauma:
| Hyperextension vs. Hyperflexion
Hyperextension = results from forces of acceleration-deceleration and sudden reduction in anteroposterior diameter of the spinal cord (usually happens in the cervical area)
Hyperflexion = results from sudden and excessive force that propels neck forward or causes an exaggerated lateral movement of neck to one side (usually happen in the cervical area)
97
Spinal Cord Trauma:
| Vertical Compression vs. rotation forces
Vertical compression = (axial loading) results from a force applied from the top of the cranium down through vertebral bodies (usually happens T12 to L2)
Rotation forces = (flexion-rotation) adds shearing force to acceleration forces (usually happens in the cervical area)
98
Spinal cord shock
a temporary suppression of neurologic function because of spinal cord compression.
neurologic function gradually returns
99
Autonomic hyperreflexia
a massive sympathetic response that can cause HA, hypertension, tachycardia, seizures, stroke, and death; most commonly associated with injuries above T6).
Can also be caused by a distended bladder or rectum or any sensory stimulation.
100
Cerebral vascular accident
(CVA) or stroke refers to an interruption of cerebral blood supply
permanent damage
an infarction of the brain, so it is often referred to as a brain attack
101
A transient ischemic attack
(TIA) refers to a temporary episode of cerebral ischemia that results in neurologic deficits (sometimes referred to as ministrokes).
can mimick CVAs but the difference is that TIAs resolve with 1-2 hours (24 hours at the most).
TIAs may be warnings that a CVA is impending.
102
What are the (2) types of CVA's?
Ischemic = most common
Hemorrhagic = most deadly.
103
How long does it take altered tissue perfusion to lead to irreversible cell damage from the lack of oxygen and glucose.
5 minutes
104
Cluster headaches
more men than women
recurring headaches that occur in groups or cycles
appear suddenly and are characterized by severe, debilitating pain on ONE SIDE of the head, and are often accompanied by a watery eye and nasal congestion or a runny nose on the same side of the face; pain is steady.
unlikely to lie down, as someone with a migraine might
105
Tension headaches
the most common type, feel like a constant ache or pressure around the head, especially at the temples or back of the head and nec; pain is steady.
Experts believe these may be caused by the contraction of neck and scalp muscles (including in response to stress), and possibly changes in brain chemicals.
106
Migraine headaches
Migraines can run in families and are diagnosed using certain criteria.
```
• At least five previous episodes of headaches
• Lasting between 4–72 hours
• At least two out of these four:
----1. one-sided pain,
----2. throbbing pain,
----3. moderate-to-severe pain, and
----4. pain that interferes with activity
• At least one associated feature:
----1. nausea and/or vomiting, or
----2. sensitivity to light and sound
```
Pain is usually characterized as throbbing.
may be foreshadowed by aura, such as visual distortions or hand numbness. (About 15% to 20% of people with migraines experience these.)
107
Meningitis
Meningitis is an inflammation of the meninges that covers the brain/spinal cord.
1. Bacterial = primarily an infection of the pia mater and arachnoid, the subarachnoid space, the ventricle system, and CSF.
2. Viral = limited to the meninges.
3. Fungal = chronic and most often occurs in people with impaired immune systems.
108
Encephalitis
an inflammation of the brain that can be caused by the same infectious agents as meningitis,
may cause widespread nerve cell degeneration.
Edema, necrosis with or without hemorrhage, and increased intracranial pressure develop.
109
Multiple sclerosis
(MS) is a debilitating autoimmune condition that involves a progressive and irreversible demyelination of brain, spinal cord, and cranial nerve neurons.
damage occurs in diffuse patches throughout the nervous system and slows or stops nerve impulses.
110
Amyotrophic lateral sclerosis
(ALS or Lou Gehrig’s disease) is a disease that involves damage of the upper motor neurons of the cerebral cortex and lower motor neurons of the brain stem and spinal cord.
The disease frequently begins in the upper or lower extremities and then spreads to other parts of the body. As the disease advances, muscles become progressively weaker until they are paralyzed. ALS eventually affects chewing, swallowing, speaking, and breathing.
nerves lose their ability to trigger muscle movement, resulting in muscle weakness, disability, paralysis and eventually death (usually within 5 years of onset of symptoms).
111
Guillain-Barre syndrome
an inflammatory demyelinating disease of the peripheral nervous system or a lower motor neuron disorder.
one of the most common causes of non-traumatic paralysis in the Western world.
sometimes follows an infection, inoculation, or surgical procedure in the prior 1-8 weeks before signs and symptoms occur.
segmental demyelination of nerves by T cells and B cells. This process slows or stops nerve conduction.
Primarily motor neurons are affected
progressive ascending weakness or paralysis.
