Unit 3 - Seizure Disorders Flashcards
epilepsy
seizures that are recurrent, spontaneous, and unprovoked. Seizures can affect functional status, social status, emotional status, cognition, and overall quality of life
what is a seizure?
Any sudden attack of altered behavior, consciousness, sensation or autonomical function that is produced by self-limited disruption of brain activity due to repetitive, simultaneous electrical discharges from hyperexcitable neurons in the cortex
epilepsy facts
- affect 2.3 million americans
- incidence highest for under 2 and over 65
- males > females
- 8% kids will have 1+ by age 15
for people with diagnoses with epilepsy
- 65% achieve control after the first year
- 15% achieve control at a later date
- 20% resist control and seizures become refractory or uncontrollable
seizure types
- Generalized
2. Partial
generalized seizures and 4 types
- affect both hemispheres of the brain simultaneously. They account for 40% of all cases of epilepsy
- tonic clonic
- absence
- atypical absence
- myoclonic
Tonic-clonic seizures (grand mal, major motor)
- Most common variant in childhood
- May result from fever, CNS infection, metablolic disturbance, tumor, developmental brain abnormality (CP), or hereditary tendency
- PRIMARY generalized seizures appear to originate simultaneously in all areas of the brain
- SECONDARY generalized seizures evolve from initially localized events in one area of the brain
*This localized event is often indicated by a brief, sometimes nonspecific aura or warning preceding the actual seizure.
tonic clonic phase details
Tonic stage: appears first and lasts about 30 sec. to 1 minute. The seizure can begin with eye deviation upward or to one side, sudden loss of consciousness, and rigidity. The child may stop breathing (color change).
Clonic phase: follows with rhythmical jerking of the body, lasting 1-3 minutes.
• The clonic phase is usually followed by lethargy or sleep
• Incontinence may occur in this postictal period
• Upon recovery, the child typically has no memory of the seizure itself.
• Some people can have purely tonic or purely clonic seizures.
Absence Seizures (formerly called petit mal)
• Much less common than tonic-clonic seizures
• Account for less than 5% of all seizure disorders
• Onset typically occurs in the first decade of life between 3 and 7 years of age
• The child abruptly stops all activity, assumes a glazed look, stares, and remains unaware of surrounding for several seconds
• The child maintains normal muscle tone which can protect the child from falling. Many times, though a child with severe absence seizures may wear a helmet to protect the head if the child falls during a seizure
• Video EEG has shown a high degree of subtle eye blinking, muscle twitching, or repetitive movement.
• Unlike daydreaming, absence seizures cannot be interrupted by verbal or tactile stimulation
• This type of seizure is difficult to detect
*due to brevity of the seizure and the LACK of any postictal confusion following the seizure. Many children can respond almost immediately to a question or resume activity where they have left off.
• Spontaneous remission can occur in 90% of childhood absence epilepsies
Atypical Absence
- Involve complex staring spells and associate focal features
- Starts gradually, lasts longer, and ends with postictal confusion
- Typically seen in children with mental handicaps and may present with mixed type seizure patterns (ie. tonic-clonic, myotonic, atonic qualities)
- Lennox-Gestaut syndrome is another name for these intractable mixed seizures that may be associated with mental handicaps and developmental disabilities
Myoclonic
• Sudden and powerful involuntary contractions of muscles
• A hand may fling out or spasms may involve the entire body and cause the child to be thrown to the ground
• Infantile spasms is a classic example of myoclonic seizures
*Infantile spasms may start at 4-8 months of age
*Occur in children with a variety of brain disorders as well as typically developing infants
*Can look like an exaggerated Moro reflex
*They occur during periods of drowsiness or arousal from sleep
*Occur in clusters of 5 or more, each separated by a few second and can last up to 5 minutes
*The spasms usually take the form of a sudden jackknifing of the body with forward bending at the waist with arms and legs outstretched
*More that 90% of children with symptomatic infantile spasms develop mental handicaps despite medical intervention (drugs)
Partial Seizures
The most common type of seizure disorder, account for ~60% of all cases. ~3/4 of all children affected by partial seizures have brain abnormalities, most commonly of prenatal origin. The signs and symptoms of the seizure depend on the seizure focus in a restricted area of one hemisphere
Simple Partial Seizures
- Commonly first identified after 4 years of age
- If the seizure focus involves the motor cortex, the result is usually rhythmic clonic activity of the face, arm, or leg. Can include isolated twitching of 1 extremity
- If the seizure activity arises from the occipital or parietal lobes, visual hallucinations or illusions may occur
- If the seizure activity arises from the temporal lobe, auditory hallucinations or olfactory sensation by occur
- An aura may precede a simple complex seizure – a feeling of déjà vu
- Consciousness is not lost, and the child can remember the sensations from the seizure
- ~70% of simple partial seizures can be controlled by anti-epileptic drugs (AEDs)
Complex Partial Seizures (psychomotor, limbic, temporal lobe)
- Most common seizure type in older children and adolescents, may not be seen in infancy
- Resemble generalized absence seizures
- Are distinguished by an aura that preceded the seizure, a duration longer than 10 minutes, and postictal confusion or actual sleeping
- Most originate in the temporal lobe
- Auras may include sudden familiar odor, an odd taste, a visual hallucination
- The child may also have unprovoked emotional outbursts such as anger, laughter, or fear
- The seizure could include eye blinking, lip smaking, facial grimacing, groaning, chewing/rumination, unbuttoning/buttoning clothing and aimless wandering
- Spontaneous remission occurs in ~20% of cases, but many children respond well to AEDs
Diagnosis of Seizure Disorders
• EEG – Electorencelphalolgram
*~80% of all children with seizure disorders have abnormal EEG pattern between seizures (Batshaw, M., 2010).
*Often, physicians try to “evoke” seizures while child is undergoing an EEG by using various stimuli to see what may trigger a seizure (ie. light, sounds, sleep deprivation, medication changes)
• History and physical
• MRI and other scans of the brain
• Neuropsychological testing
