Chapter 20: Epilepsy and Seizure Disorders

Question 1

DEFINITION:

What is the International League Against Epilepsy (ILAE) definition of a SEIZURE?

Answer 1

“a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.”

**Note: seizures are, in most cases, a symptom of an underlying pathological condition or process affecting brain function

Question 2

DEFINITION:

Localization-related seizure

Answer 2

associated with a specific area of abnormality in the brain and can include alterations in behavior associated with functions of the region in which the seizure originates.

generally involve more limited networks, typically within one hemisphere

Question 3

DEFINITION:

Generalized or nonlocalized seizures

Answer 3

typically associated with more DIFFUSE abnormalities or with bursts of abnormal brain activity that result in loss of awareness or consciousness but without more specific sensory or behavioral features.

generally arise in and rapidly engage BILATERALLY distributed networks

Question 4

DEFINITION:

Epilepsy

Answer 4

recurrent, unprovoked seizures

• *Can be:
• Acquired
• Congenital

**Age of onset is used in the working

Question 5

What clinical features are seizures classified?

Answer 5

1) Involved networks
- Generalized
- Localized

2) Degree of impairment in consciousness or awareness
- “with alteration in consciousness or awareness”

Question 6

What features characterize FOCAL SEIZURES?

Answer 6

Focal seizures are characterized by ONE or MORE features:

• Aura
• Motor
• Autonomic
• Awareness/Responsiveness altered (dyscognitive) or retained

**may evolve to bilateral convulsive seizures.

Question 7

DEFINITION:

Aura

Answer 7

a subjective sensory phenomenon that precedes a seizure and may serve as a warning tot he person with epilepsy that seizure may be imminent.

**Not all auras are followed by observable seizures. When an aura occurs alone, it is considered a sensory seizure

Question 8

DEFINITION:

Febrile seizure

Answer 8

a seizure brought on by a fever, typically higher than 102F.

Approximately 4-5% of children will have at least one febrile seizure. Febrile seizures do NOT constitute epilepsy and are not usually treated with AEDs.

However, febrile seizures are a risk factor for later development of unprovoked seizures, particularly seizures arising from the temporal lobe.

Question 9

DEFINITION:

Ictus

Answer 9

A sudden neurological occurrence, such as a seizure.

Ictal behaviors = behavioral changes that occur during a seizure –> considered important lateralizing and localizing signs!!

Question 10

DEFINITION:

Interictal

Answer 10

refers to the period between seizures; for example, interictal EEG abnormalities are changes in the EEG pattern that occur between seizure and may be helpful in localizing regions of hyper excitability and/or seizure onset

Question 11

DEFINITION:

Postictal

Answer 11

refers to the period of time after a seizure occurs, as in postictal confusion or drowsiness

Question 12

DEFINITION:

Idiopathic or cryptogenic epilepsy

Answer 12

seizures in which the cause is not readily identified (e.g., no known historical risk factors, normal neurological exam, and normal imaging)

***NOTE: However, these cases more likely are associated with causes that have yet to be identified, such as genetic conditions affecting neuronal activity (e.g., ion channel genes) or expression and function of neurotransmitters such as GABA.

Question 13

DEFINITION:

Kindling

Answer 13

The development of an epileptogeneic network by exposure to recurrent seizures.

Can occur in homologous areas of the contralateral hemisphere or within the same hemisphere as seizure onset through repetitive spread of seizures to areas of the brain functionally connected to the epileptogenic cortex.

Question 14

Temporal lobe epilepsy is an example of _____.

A) catastrophic epilepsy
B) localization-related epilepsy
C) primary generalized epilepsy
D) psychogenic seizures

Answer 14

B - localization-related epilepsy

Seizures begin in a localized area, such as the temporal lobe, are by definition, localization related

Question 15

Epilepsy is defined as _____.

A) recurrent unprovoked seizures
B) medication resistant seizures
C) multiple different seizure types
D) seizures associated with transient metabolic changes

Answer 15

A - recurrent unprovoked seizures

epilepsy is not necessarily medication resistant, and many persons with epilepsy can achieve good control of seizures with medication. Many persons with epilepsy, particularly localization-related epilepsy, have only one seizure type.

Question 16

Which of the following epilepsy syndromes is most likely to show spontaneous remission?

A) temporal lobe epilepsy (TLE)
B) childhood absence epilepsy (CAE)
C) Lennox-Gastaut
D) frontal lobe epilepsy

Answer 16

B - childhood absence epilepsy

The natural history of epilepsy syndromes is quite variable, but of the syndromes listed, CAE is the most likely to remit during early adolescence. However, up to 15% of children with CAE will go on to develop juvenile myoclonic epilepsy.

Question 17

The most common underlying pathology in adult epilepsy is ____.

A) low grade glioma
B) malformation of cortical development
C) hippocampal sclerosis
D) traumatic brain injury

Answer 17

C - Hippocampal sclerosis

Although all of the listed pathologies are associated with adult epilepsy, the most common pathology is mesial temporal lobe sclerosis, accounting for up to two-thirds of cases.

Question 18

Which of the following is most accurate regarding memory deficits in persons with epilepsy?

A) Memory deficits in frontal and temporal lobe epilepsy are the same
B) Memory deficits in TLE do not lateralize to the side of seizure onset
C) In TLE, verbal memory impairments are only present in left-side seizure onset.
D) Verbal memory deficits in left TLE are more robust than visual memory deficits in right TLE

Answer 18

D - Verbal memory deficits in left TLE are more robust than visual memory deficits in right TLE

Note:
Exacerbation of deficits following dominant temporal lobectomy is predictable based on presurgical memory ability. However, the presence of nonverbal memory deficits in RIGHT TLE is not as consistently observed, and, in many cases of right TLE, there are no memory deficits. This may be due to a combination of factors, including methodological differences and a lack of coherence between methods of nonverbal memory and tests that are used to assess the construct

Question 19

Studies of depression in epilepsy have found that ____.

A) patients with left TLE are more depressed than patients with right TLE
B) patients with right TLE are more depressed than patients with left TLE
C) neither patients with right TLE or left TLE show depression
D) both patients with right TLE and left TLE show depression.

Answer 19

D - both patients with right TLE and left TLE show depression.

Although some studies have suggested a lateralized mood effect, the majority of studies show higher incidence of depression and anxiety in persons with epilepsy, regardless of laterality of seizure onset. More important factors are severity of epilepsy and seizure frequency.

Question 20

The most common underlying pathology in PEDIATRIC epilepsy is ____.

A) low grade glioma
B) malformation of cortical development
C) hippocampal sclerosis
D) traumatic brain injury

Answer 20

B - Malformation of cortical development

In children, the most common underlying pathology is malformation of cortical development.

Question 21

Classification of recurrent seizures into epileptic syndromes takes into account all of the following except _____.

A) age of onset
B) electroclinical features
C) ictal and interictal behavior features (including neuropsychological status)
D) psychosocial effects of seizures

Answer 21

D - Psychosocial effects of seizures

Although psychosocial status is increasingly recognized as an important aspect of seizure treatment, it is not a consideration in classification of seizure syndromes.

Question 22

Which of the following is not considered to be a common cause of epilepsy?

A) brain tumor
B) cerebral-vascular insult
C) meningitis
D) concussion

Answer 22

D - Concussion

Uncomplicated concussion or mild traumatic brain injury may be considered, in some studies, to be a risk factor, but is not a common cause of epilepsy.

In contrast, traumatic brain injury that involves cerebral contusion, penetrating skull fracture, or other clear injury to the brain is associated with a substantial increased risk of later epilepsy.

**Early postinjury seizures increases the risk of developing epilepsy at a later time as well.

Question 23

Malformations of cortical development (MCD) are classified on the basis of all of the following, except ____.

A) histological features
B) imaging characteristics
C) seizure type
D) genetic and embryological principles

Answer 23

C - Seizure type

Although different MCD may be associated with different epilepsy syndromes, seizure type or epilepsy syndrome is not a basis for classification of MCD; classification is based on imaging studies, histological features when biopsy or resection is performed, and genetic and embryological principles.

Question 24

Which of the following statements about persons with epilepsy is TRUE?

A) Persons with epilepsy are typically intellectually disabled
B) Persons with epilepsy are prone to violence and aggressive behavior
C) Persons with epilepsy are are likely to be under- or unemployed
D) Persons with epilepsy typically have associated psychotic disorders.

Answer 24

C - Persons with epilepsy are are likely to be under- or unemployed

Question 25

Which of the following is not a likely outcome following temporal lobectomy?

A) material specific memory impairment
B) Gerstmann Syndrome
C) Word-finding problems
D) superior quadrantanopsia

Answer 25

B - Gerstmann Syndrome

Gerstmann syndrome is associated with lesions in the angular - supramarginal gyrus and would not be expected as a consequence of temporal lobectomy.

Question 26

Decreased processing speed is associated with each of the following, except ____.

A) decreased white matter volume
B) suppression of neuronal excitability with AED treatment
C) decreased memory and mesial temporal sclerosis
D) seizures involving frontal lobe networks

Answer 26

C - decreased memory and mesial temporal sclerosis

Side effects of tx with AEDs commonly include decreased processing speed. Studies have also shown that in persons with epilepsy there is a relation between decreased overall white matter volume and processing speed, as well as involvement of frontal lobe systems in seizure onset or propagation.

Question 27

Depression and anxiety in persons with epilepsy are ____.

A) not consistently reported due to poor insight
B) typically not severe enough to warrant treatment
C) more common than in other chronic illnesses
D) not as common as in other chronic illnesses

Answer 27

C - more common than in other chronic illnesses

Higher rates of depression and anxiety are consistently reported among persons with epilepsy. when compared with other chronically ill groups, including those having a high incidence of childhood onset (e.g., diabetes), epilepsy has a higher rate of depression.

Severe depression, including suicidality, is not uncommon, and tx of depression is a key component of maintaining quality of life.

Question 28

Which of the following statements about IQ in persons with epilepsy is TRUE?

A) Verbal IQ - Performance IQ (VIQ-PIQ) discrepancies are a lateralizing sign in children, but not adults
B) IQ scores typically decline over time in person with epilepsy
C) Most persons with epilepsy have low IQ scores
D) Age at seizure onset is a factor in how IQ is affected

Answer 28

D - Age at seizure onset is a factor in how IQ is affected

VIQ-PIQ discrepancies are not lateralizing unless there is a LARGE discrepancy.

Most important factor is age at seizure onset, with earlier age of onset associated with lower IQ.