PATHO Ch. 18 Disorders of the CNS + PNS + Neuromuscular junction

traumatic brain injury

mild or severe trauma that can result from a violent impact to the head

focal tbi

specific, local observable lesions. Includes contusions and hematomas.

diffused tbi

multiple areas of the brain are compromised or damaged

closed tbi

the brain is injured but the skull is NOT BROKEN, fractured, or penetrated

- the dura is NOT torn

open tbi

brain injury where the skull is broken, fractured, or penetrated.

- the dura is torn in a penetrating injury

Glasgow Coma Scale (GCS)

a scale used to assess the consciousness of a patient upon physical examination, typically in patients with neurological concerns or complaints

high GCS

better

lower GCS

severe brain injury

hallmark of brain injury

loss of consciousness more than 6 hours

coup tbi

brain damage at site of blow

countercoup tbi

Rapid acceleration/deceleration

-The brain is damaged on the opposite side

- car accidents

indirect injury

force applied to another body part with a rebound effect to the brain

secondary injury

brain damage that occurs as a response to the initial injury. ex: hematoma, hypoxia, ischemia, increased intracranial pressure, and post-traumatic epilepsy

TBI treatment (contusions)

need to relieve intercranial pressure

- shunt

- remove hematomas

brain contusions can cause

Epidural (extradural) hematoma

Subdural hematoma

Intracerebral hematoma

epidural (extradural) hematoma

a hematoma located on top of the dura

can occur in spinal cord

- loss of consciousness at time of injury followed by lucid period

- due to bleeding vein

subdural hematoma

a hematoma located beneath the dura

- subarachnoid space

- can resolve

- develop within 48 hrs. of skull fracture

intracerebral hematoma

a hematoma located inside the brain tissue

- ventricles

- can be chronic

- craniotomy can remove

An unconscious person is admitted to the hospital after a motorcycle accident. The person experienced a brief loss of consciousness at the scene followed by an awake, lucid period of 1 hours. You suspect this individual has a(n)

extradural hematoma

concussion

violent shaking up or jarring of the brain

- bruising of brain

- damage to axonal fibers + white matter tracts

- blunt damage to gray matter

concussion complications

post concussion syndrome

post traumatic seizures

chronic traumatic encephalopathy

post concussion syndrome

lingering symptoms from a concussion that last for an extended period of time

post concussive syndrome symptoms

- Light headedness

- Vertigo

- Headache

- Nausea

- Vomiting

- Photophobia

- Cognitive and memory dysfunction

- Tinnitus

- Blurred vision

- Difficulty concentrating

- Amnesia

- Fatigue

- Personality change

- Balance disturbance

post concussive syndrome treatment

-supportive (managed by PCP)

-close observation for 24 hours for immediate intervention due to a slow bleed

post traumatic seizures

Seizures occurring after a traumatic brain injury.

- epilepsy

Chronic Traumatic Encephalopathy (CTE)

a progressive, degenerative condition involving brain damage resulting from MULTIPLE episodes of head trauma

- football + boxing

- only diagnosed after death

mild concussion

Temporary axonal disturbance causing attention and memory deficits but no loss of consciousness

- symptoms usually resolve in 15 mins

moderate concussion

LOC of 30 min to 6 hrs. GCS-9-12

No brainstem injury, usually some permanent deficiencies

- skull fractures

severe concussion

- LOC more than 6 hours

- GCS 3-8

- signs of brainstem injury, permanent deficiencies, vegetative state or even death from TBI or complications

decerebration

condition of loss of mental functions caused by damage to the midbrain

- dysfunction of white matter

spinal cord injury

the type of paralysis is determined by the level of the vertebra closest to the injury

primary spinal cord injury

segmental paralysis at level of lesion or below

- dysfunction in lower motor neurons

- mechanical damage to white matter tracts or gray matter in spinal cord

secondary spinal cord injury

Result of vascular, chemical, and inflammatory process that follows primary injury

clinical manifestations of spinal cord injury

spinal shock

neurogenic shock

autonomic dysreflexia

who do spinal cord injuries affect most?

young men

- most common in car accidents

- falls

- violence

spinal shock

total loss of reflexes below level of lesion

- flaccid paralysis, sensory deficit, loss of bladder + rectal control, drop in BP, disturbed temperature

- days up to 3 months

- results in poor venous circulation

neurogenic shock

cervical or upper thoracic injuries

- In addition to spinal shock.

- caused by absence of sympathetic activity and unopposed parasympathetic tone mediated by an intact vagus nerve

- vasodilation

Autonomic Dysreflexia

life-threatening condition that occurs in individuals with spinal cord injuries at or above T6.

- results from exaggerated autonomic response to a noxious stimulus below the level of the injury

- leads to severe hypertension, bradycardia, and other autonomic disturbances.

most common spinal cord injury

contusions

- caused by bending of vertebral column

- COMPRESSION ON CORD

You know that spinal shock results in

poor venous circulation

Degenerative Disc Disease

gradual breakdown of spinal discs due to aging, wear and tear, or injury.

- Discs lose water, shrink, and become less flexible, leading to pain, stiffness, and reduced mobility.

spondylolysis

the breaking down of the vertebral structure

- hereditary

- soft tissue damage

spondylolisthesis

forward slipping of one vertebra over another

spinal stenosis

narrowing of the spinal canal

herniated disc

soft inner core of an intervertebral disc pushes through a tear in the outer layer, potentially pressing on nearby nerves

- pain

- can be repaired

- sciatica

- hip pain

most common neurologic disorders

- CVA's (strokes)

- transient ischemic attacks

- aneurysms/ malformations

cerebrovascular accidents (CVAs)

strokes

Transient ischemic attacks

mini strokes

- twitching

- usually not permanent

CVA (stroke)

5th leading cause of death

- minimal or life threatening

- greatest risk factor: hypertension

ischemic stroke

stroke that occurs when the flow of blood to the brain is BLOCKED

- aspirin can help

- blockage can be from thrombocytes, embolisms

lacunar stroke

a stroke resulting from occlusion of a small penetrating artery with development of a cavity in the place of the infarcted brain tissue

- less dysfunction

- smaller areas

hemorrhagic stroke

occurs when a blood vessel in the brain leaks or ruptures; also known as a bleed

- lower fat intake

- can cause epilepsy

CVA (stroke) artery

usually the middle cerebral artery

intracranial aneurysm

bulging artery caused by a weakening in the arterial wall

- usually from atherosclerotic disease

Saccular (berry) aneurysm

Most common cause of subarachnoid hemorrhage

- congenital (present at birth)

Fusiform (giant) aneurysms

entire artery swells

- from arteriosclerotic changes

Mycotic aneurysm

aneurysm caused by infection

Traumatic (dissecting) aneurysm

show up when they burst

- usually you don't know

- headache

- vomiting

You recall that fusiform aneurysms are

due to arteriosclerotic changes

arteriosclerotic

Narrowing of the lumen of arteries resulting in decreased blood supply to the extremities

cavernous angiomas

Sinusoidal collections of blood vessels without interspersed brain tissue

capillary telangiectasias

dilated capillaries in brain tissue

venous angioma

most common

primitive embryologic veins in a radial pattern feeding a central vein

arteriovenous malformation (AVM)

a vascular malformation that is a tangle of abnormal blood vessels connecting arteries and veins in the brain

- can lead to hemorrhage

- surgical treatment

migraine

severe, recurring, unilateral, vascular headache

- light sensitive

cluster headache

Unilateral, severe periorbital headache with tearing and conjunctival erythema.

- several attacks at once

tension headache

most common

- tight band of squeezing pressure

- from muscle tension

headaches are caused by

change in intercranial pressure or pressure in the head muscles

- changes in vasculature

A person arrives at the clinic and reports a unilateral headache for 2days that worsens with movement and light. No trauma has occurred. You suspect

migraine

Chronic paroxysmal hemicrania

Cluster-type headache that occurs with more daily frequency (4 to 12/day) but with shorter duration (20-120 minutes)

subarachnoid hemorrhage

Bleeding into the subarachnoid space, where the cerebrospinal fluid circulates.

infections of the CNS

Meningitis

Encephalitis

Brain Abscess

NeuroAIDS

Meningitis

inflammation of the meninges of the brain and spinal cord

- viral or bacterial

- pus on brain (bacterial)

brain abscess

collection of pus anywhere within the brain

- bacteria

- can cause neck stiffness, fever, headache

extradural abscess

Abscess located outside the dura mater

- can cause local pain

subdural abscess

collection of pus between dura mater and arachnoid mater

encephalitis

inflammation of the brain usually caused by a virus

- acute febrile illness

- usually arthropod or herpes

- high ICP

- in brain tissue

neuroAIDS

Neurological changes as a result of HIV/AIDS that create cognitive deficits and dementia.

- ca infect microglia + perivascular macrophages in CNS

multiple sclerosis

CNS

- demyelination

- autoimmune

- chronic inflammation

- more often in women

- lesions more common in white matter

- steroids can help, vit D and b cell therapy

Guillain Barre Syndrome

PNS

inflammation of the peripheral nerves where myelin sheaths on axons are destroyed, resulting in decreased nerve impulses, loss of reflex response, and sudden muscle weakness

- attacks schwann cells

- occurs after viral infection

- acute

- autoimmune

neuropathy

dysfunction in peripheral nerves

Generalized symmetric polyneuropathies

type of neuropathy characterized by symmetrical involvement of sensory, motor, or autonomic fibers

- diabetic neuropathy

- guillain barre

generalized neuropathies

sensory or motor

what is usually affected by neuropathy?

usually the feet/ lower limbs

radiculopathies

Disorders of spinal nerve roots

- Caused by compression, infection, inflammation, ischemia, or direct trauma

- action potential prevented

plexus injuries

occurs when the nerve networks (brachial or lumbosacral plexus) are damaged due to trauma, stretching, or compression, leading to weakness, numbness, or paralysis in the affected limb

- rehab

- amino acids

- repair tissues

neuromuscular junction disorders

Myasthenia gravis, Lambert-Eaton syndrome

myasthenia gravis

a chronic autoimmune disease that affects the neuromuscular junction by producing antibodies (IgG) against acetylcholine receptors

- can paralyze diaphragm

- immunotherapy best cure

Lambert-Eaton myasthenic syndrome

body's immune system attacks calcium channels at the nerve endings, reducing neurotransmitter release and causing muscle weakness.

primary brain tumor (gliomas)

brain tumor that originates in the brain

- radiotherapy most affective, chemo cat get through BBB

- compression causes the issues

glioblastoma

malignant brain tumor arising from glial cells

- worst form

- stage 4 astrocytoma

oligodendroglioma

Malignant tumor of oligodendrocytes

astrocytoma

tumor deriving from Astrocytes; basically benign, slowgrowing tumor.

- surgery, radiation

- most common

ependymomas

Tumor arising from the wall of the fourth ventricle, especially in children, and the lateral ventricles in adults

- non capsulated makes surgery hard

meningiomas

tumors that grow between the meninges

- slow growing

- capsules

- pressure causes seizures

- surgery + drugs to reduce tumor

brain tumor symptoms

compression causes cerebral edema

- headache

- vomiting

- seizure

-behavioral issues

brain metastases

The spreading of a primary tumor to the brain.

- usually from Lung, breast, kidney cancers

- common place of metastases