Patho. Neurological Disorders

What are the 3 symptoms/factors of Cushing’s Triad?

cushing’s Triad - damaged brainstem → affecting breathing, heartbeat, and blood pressure

the brainstem is responsible for basic vital life functions

What is parkinson’s Disease?

A chronic, progressive neurodegenerative disorder that affects movement due to the loss of dopamine-producing neurons in the brain, leading to tremors, stiffness, and difficulty with balance and coordination.

Complete the sentence:
Parkinson’s disease is due to degeneration of nerves in the substantia nigra in the ________ and to low concentrations of ________.

Complete the sentence:
Parkinson’s disease is due to degeneration of nerves in the substantia nigra in the basal ganglia and to low concentrations of dopamine.

What is the function of the basal ganglia?

The basal ganglia help regulate and coordinate voluntary motor movements, posture, and muscle tone — they ensure smooth, controlled movement.

What are the 3 hallmark categories of Parkinson’s disease manifestations?

• Tremor: Often at rest (“pill-rolling” tremor of the hands).

• Rigidity: Muscle stiffness and resistance to movement.

• Bradykinesia (and akinesia): Slowness or absence of voluntary movement — can lead to shuffling gait and difficulty initiating motion.- Can’t start movement, can’t change direction or stop movement once started.

• Dementia (from slides) - cognitive dysfunction occurs in 20-30% of persons with the disease, late in progression of disease.

How does blood supply affect signs and symptoms of brain damage?

it depends which blood vessel is damaged and which part of the blood vessel is damaged.

What is the cause of parkinson’s disease?

degeneration and low dopamine, as well as genetic and environmental factors

What is Amyotrophic Lateral Sclerosis? (ALS)

ALS is a progressive neurodegenerative disease that affects both upper and lower motor neurons, leading to muscle weakness, paralysis, and eventual loss of voluntary movements

What is the pathology of Amyotrophic Lateral Sclerosis? (ALS)

ALS involves degeneration and death of motor neurons in the brain (upper) and spinal cord (lower).
This results in loss of nerve signal transmission to muscles, causing them to weaken, waste away (atrophy), and lose function

What neurons are affected by ALS?

Both upper motor neurons (in the brain) and lower motor neurons (in the spinal cord and peripheral nerves).

How does ALS progress?

ALS usually begins with muscle weakness and twitching in one area (legs) and gradually spreads.
Over time, muscle control is lost, leading to paralysis while cognitive function typically remains intact.

It is ascending to it starts in the legs and moves upward. 

What is the most common cause of death in ALS? 

Respiratory failure, due to weakness and paralysis of the respiratory muscles.

What if ALS progresses to C3, C4, and C5? 

respiratory muscle failure, no diaphragm movement 

What is Multiple Sclerosis? (MS) 

a chronic, progressive autoimmune disorder that affects the central nervous system, causing demyelination of neurons and disrupting nerve signal transmission.

What is seen in MS lesions in early and later stages?

• Early stages: Inflammation.

• Later stages: Gliosis (scarring or plaque formation).
  These lesions disrupt nerve signaling and cause neurological symptoms.

What is damaged in MS?

Myelin sheaths of CNS neurons are damaged, slowing or blocking electrical impulses along nerves.
Axons may also eventually be damaged.

What is the general pathophysiology of MS?

• Autoimmune attack against CNS myelin.

• Inflammation causes myelin loss.

• Plaque formation (gliosis) occurs in later stages.

• Nerve conduction slows or stops, causing neurological deficits.

What is the clinical presentation of a patient with MS?

-vision loss and double vision

-bladder and sexual dysfunction 

-incoordination 

-mood, memory, thought, concentration 

paresthesias, numbness 

True or false: is multiple sclerosis usually relapsing-remitting? 

true, often no dysfunction between episodes 

What causes Multiple Sclerosis (MS)?

we are unsure what causes it get

What is an epidural hematoma?

arterial bleeding between the skull and dura mater

• middle meningeal artery 

• most serious head injury 

• usually associated with a skull fracture 

What are signs and symptoms of an epidural hematoma? 

fast bleeding bc it is arterial 

unconsciousness, and then lucid intervals (but not always) 

rapid deterioration to unsconsciousness - focal neurological deficits (opposite side) - pupil dilation (same side)

What is a subdural hematoma / hemmorhage?

venous bleeding in the subdural space, between dura mater and arachnoid mater

• bridging veins and venous sinuses

• associated with brain moving in skill 

Signs and symptoms of subdural hematoma?

slow bleeding bc of venous bleeding 

my be asymptomatic for hours, days or weeks 

confusion, Head ache, altered consciousness 

(all of these may fluctuate over time) 

What is a subarachnoid hematoma / hemorrhage?

artery bleeding in the subarachnoid space (between arachnoid and pia mater)

• rupture of cerebral artery 

• aneurysmal subarachnoid: small outpouching vessel 

What can a subarachnoid hematoma / hemorrhage lead to?

hemorrhagic stroke

Signs and symptoms of subarachnoid hematoma / hemorrhage?

fast bleeding - bc artery

sudden onset head ache, dizziness, nausea and vomiting 

neck stiffness / meningeal irritation 

photobhobia and blurred vision - 

What is a stoke?

a disruption of cerebral (or cerebellar) blood flow which causes neurological deficits that are permanent.

• also called a cerebrovascular accident 

What are the 2 types of strokes? 

Ischemic - descreased blood flow

Hemorrhagic - bleed into brain tissue 

What is a Transient Ischemic Attack? (TIA)

like a mini stroke but temporary and reversible

What are common causes of ischemic stroke?

thrombosis - blood clot in a cerebral artery

Embolism - clot or debris from heart or large vessels 

Atherosclerosis - narrowing cerebral arteries 

• cerebral arteriosclerosis

• carotid stenosis

Atrial fibrilation

How can atrial fibrillation (AFib) lead to ischemic stroke? 

AFib causes irregular heartbeats → blood can pool in the atria → formation of clots → clots can travel to brain arteries → ischemic stroke

How is a TIA different from ischemic and hemorrhagic stroke?

it is a temporary blockage of blood flow

symptoms resolve within 24 hours and usually without permanent damage 

unlike full strokes, no lasting infarction occurs 

Why are TIAs considered a true medical emergency?

they are warning signs of possible future strokes. Prompt evaluation and treatment can prevent permanent brain damage 

What is Ischemic penumbra?

the permeter around the core ischemic area

why is reperfusion important in the ischemic penumbra?

it is critical because if left untreated it will become ischemic and infarction (dead tissue) 

How can reperfusion be a double edge sword in ischemic penumbra?

(ischemia causes cellular damage and creates free radicals) 

Blood flow needs to be restored but it also carres free radicals downstream so then these free radicals can attack other cells and cause further cellular injury (reperfusion injury) 

What is a hemorrhagic stroke?

a stroke caused vy rupture and hemorrhage of a cerebral artery, leading to compression of brain cells and loss of cerebral blood flow. blood is toxic to brain cells

Which artery is most likely to bleed in hemorrhagic stroke?

The middle cerebral artery. But any cerebral artery can rupture.

What are the common causes of hemorrhagic stroke?

aneurysm rupture

tumors eroding into vessels

AVM Ateriovenous malformations

bleeding disorder

What are risk factors for stokes?

hypertension

Afib

diabetes

smoking

hyperlipidemia

obesity / sedentary lifestyle

age and family history

previous stroke / TIA

sickle cell disease

oral contraceptives 

What are common signs and symptoms of stroke?

sudden weakness or numbness (usually one side)

confusion, trouble speaking, or understanding speech

vision changes in one or both eyes 

dizziness, loss of balance, or loss of coordination 

severe headache 

loss of sensation 

loss of gag reflex

loss of vision

some patients have disorientation, confusion, and sleepiness that can become near unconsciousness or coma 

What does FAST stand for in stoke recognition?

F- Face drooping

A - Arm weakness 

S - Speech difficulty 

T - time to call emergency services

If it is a right cerebral hemisphere stroke is it hemiparesis or hemiparalysis on what side?

on the left side

If it is a left cerebral hemisphere stroke is it hemiparesis or hemiparalysis on what side?

right side

What is hemiparesis?

weakness of extremities on one side of the body

What is hemoparalysis?

complete loss of function of extremities on one side of the body

What happens in cerebral edema within the ischemic penumbra and surrounding brain tissue?

Swelling occurs in the brain tissue, which contributes to hypoperfusion (reduced blood flow) and further damage to brain cells.

What is anoxic encephalopathy and how does it relate to cerebral edema?

Lack of circulation reduces oxygen delivery to brain tissue, causing anoxic encephalopathy, which leads to a decreased level of consciousness.

Why is cerebral edema especially dangerous inside the skull?

Swelling brain cells are enclosed by the cranial bones, which allow very little room for expansion, increasing intracranial pressure.

Where is the pressure directed when it builds inside the skull due to cerebral edema?

Pressure is directed downward toward the foramen magnum, where the spinal cord enters the brainstem.

What can happen if cerebral edema causes pressure on the brainstem?

• Level of consciousness decreases

• Vital signs are affected

• Potential for death due to brainstem compression

What are the key signs of cerebral edema affecting the brainstem?

• Diminished level of consciousness

• Irregular respiratory rate

• Bradycardia (slow heart rate)

• Hypertension (high blood pressure)

• Together, these are called Cushing’s triad.

How are stokes diagnosed?

Computed Tomography (CT) scans

• without contrast are often preferred during the acute phase of the stoke 

• the importance of a CT scan is to identify or exclude hemorrhage as the cause of the stroke 

• Treatment is based on whether the stoke is ischemic (blood supply) or hemorrhagic (stopped blood flow)