Neuro/MSK #5 Flashcards
This scar tissue is found in the areas of the brain where abnormal firing of neurons begin:
Gliosis
glee-oh-sis
Leads to cavitation.
Name some metabolic disturbances that may cause a seizure:
- Acidosis
- Electrolyte imbalance (Esp Na)
- Dehydration or water intoxication (still Na)
- HypOglycemia
- Hypoxemia (decreased O2 in blood)
- Alcohol or barbiturate withdrawal (malnurished)
What are the two categories of causes of seizures?
- Metabolic disturbances
2. Extracranial disorders
What are the 4 extracranial disorders that may cause a seizure?
- HTN
- Diabetes M can cause:
- Sepsis
- Systemic lupus erythematosus
This condition is due to spontaneous, recurring seizures caused by an underlying chronic condition:
Epilepsy.
- approx 3 million ppl in US have.
- increasing in older adults
- increasing in African American and lower socio-eco
- slightly more common in males
- around 200,000 new cases/yr
What are the two classifications of seizures (types)?
These are determined by the site (focus) of electrical disturbance…
- Focal seizures: begin in specific REGION of brain
- Generalized: BOTH sides of brain
What are the 4 phases that a seizure may involve?
- Prodromal phase: a sensation. Pt may not experience or be aware of, we may not see.
- Aural phase: halucination/halo is seen (sensory).
- Ictal phase: the actual seizure activity.
- Postictal phase: rest and recovery.
This involves bilateral synchronous discharges:
General seizure.
There is no warning or aura.
Most of time pt loses consciousness for a few seconds to several minutes.
This type of general seizure is characterized by loss of consciousness and falling, the body stiffens with subsequent jerking of extremities:
Tonic-clonic seizures:
Body stiffening (tonic) Jerking extremities (clonic)
May experience cyanosis, drooling, foaming, tongue/cheek biting, incontinence.
This type of general seizure is characterized by a staring spell with other manifestations such as clicking tongue or rapid blinking:
Atypical Absence seizure
Adults can get these.
Have a brief warning.
Experience confusion afterward.
This generalized seizure is characterized by sudden, excessive jerk of the body and extremities:
Myoclonic seizure
Myo- muscle
Like when you’re falling asleep and jerk awake.
This type of general seizure is also known as the “drop attack” and pts will often wear helmets:
Atonic seizure
tonic- tone
Loss of muscle tone. Begins suddenly and person falls. Consciousness returns by the time they hit the ground.
Can resume normal activity immediately.
Term used when no specific cause is known for a disease or condition:
Idiopathic
Etiology of Epilepsy. There are MANY causes but name the age ranges and their common causes:
- AGE of the person. The most common causes for the first 6 months of life is severe birth injury, congenital birth defects involving the CNS, infections, and inborn errors of metabolism.
Ages 2-20: birth injury, infection, trauma to the head, genetic factors
20-30: structural lesions/ tumor, head injury, vascular disease, drugs/alcohol (on the rise).
Over 50: Stroke, metastatic brain tumor
Another cause for epilepsy that accounts for 30% of seizures:
Idiopathic
Unknown cause!
The third major/most common cause for epilepsy?
Genetics.
Some types run in families. Some are predisposed with a lower threshold.
Some are related to syndromes from their childhood.
More than 500 genes could play a role.
Physiology of epilepsy:
- Abnormal neurons spontaneously firing
- Firing can spread to adjacent or distant areas of the brain.
- Gliosis is found in areas of the brain where firing starts
- Changes in astrocytes may be a cause of recurring seizures.
How do we divide focal seizures?
Into simple or complex, according to their clinical manifestations.
This type of focal seizure involves a change or loss of consciousness, produces a dreamlike experience, displays strange behavior, no memory of before or during the seizure, and usually lasts just a few seconds:
Complex focal.
These are strange behaviors exhibited during complex focal seizures:
Automatisms
Repetitive movements, lip smacking, pedaling, pearl-rolling, unbuttoning/rebuttoning shirt, etc.
These focal seizures manifest with the patient remaining conscious, experiencing unusual feelings/ sensations that can take many forms:
Simple focal seizure.
May experience sudden unexplainable feelings of joy, anger, sadness, or nausea
May hear, smell, taste, see, or feel things that are not real.
These begin in a specific region of the cortex and produce signs and symptoms related to the function of the area of the brain involved:
Focal (partial) seizures.
Caused by focal irritations.
This type of focal seizure is also called pseudoseizures and are psychiatric in origin:
Psychogenic seizures.
They resemble epileptic seizures but accurate diagnosis usually requires use of video-EEG monitoring to capture a typical episode.
From some kind of trauma. (abuse)
The loss of full control of bodily movements; irregularity of muscular action:
Ataxia
Impaired coordination, balance, difficulty walking, etc.
Unsteadiness in standing and walking from a disorder of the control mechanisms in the brain, or from inadequate information input to the brain from the skin, muscles and joints.
