Ch. 21 - Epilepsy Flashcards Preview

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Flashcards in Ch. 21 - Epilepsy Deck (48)
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1

Definition of epilepsy

Tendency to have recurrent seizures; transient derangement of nervous system 2/2 sudden, excessive, and disorderly discharge of cerebral neurons

2

What are the 3 major seizure types?

Generalized

Partial

Unclassifiable

3

Describe the electrical discharges in generalized seizures

Bilateral, synchronous and symmetrical, involving BOTH cerebral hemispheres

4

Describe a tonic-clonic (grand mal) seizure

Tonic phase 10-15 sec (LOC, body stiffens, clench teeth, bite tongue, apnea, urinary incontinence)

Clonic phase 1-2 min (rhythmic muscle contractions)

Postictal phase (confusion and drowsiness)

5

What are the common types of generalized seizures?

Tonic-clonic (grand mal), absence (petit mal), myoclonic, tonic, atonic

6

What are the types of partial (focal) seizures?

Simple partial, complex partial

7

Describe an absence (petit mal) seizure

Brief LOC 5-10 sec with starring or blinking but only minimal motor involvement; consciousness regained with amnesia of event

8

EEG appearance of absence seizure

Bilateral synchronous 3-Hz spike and wave activity

9

What can provoke an absence seizure or its EEG abnormality?

Hyperventilation

10

Describe a myoclonic seizure

Brief, usually single, jerking of trunk +/- limbs

11

EEG appearance of myoclonic seizure

Bilateral synchronized spike and wave activity

12

What differentiates partial from generalized seizures?

Electrical activity of partial seizures starts in defined focus

13

Define simple partial vs. complex partial seizures

Simple partial - w/o impairment of consciousness

Complex partial - with impairment of consciousness

14

Where do most complex partial seizures arise from?

Temporal lobe (often begin with an aura - taste, smell, deja vu, fear)

15

What are automatisms?

Lip smacking, chewing movements, repetitive swallowing, upper limb movements

16

What happens when electrical discharge of a partial seizure generalizes?

Can have secondarily generalized tonic-clonic seizure

17

What are the 3 types of post-traumatic seizures?

Immediate, early, and late epilepsy

18

Describe immediate post-traumatic epilepsy

Occurs at the time of, or within minutes, of head injury; usually does not recur; good prognosis; does not predispose to late post-traumatic epilepsy

19

Describe early post-traumatic epilepsy

Occurs within 1 week of head injury; complicates injuries (e.g. intracranial hemorrhage, prolonged amnesia); predisposes to late post-traumatic seizures

20

Describe late post-traumatic epilepsy

Occurs after 1 week following head trauma (can be years later)

21

Factors predisposing to late post-traumatic epilepsy

Post-traumatic amnesia >24 hrs, intracranial hemorrhage, early seizures, depressed skull fracture

22

Tx of post-traumatic epilepsy

Phenytoin or carbamazepine

23

What is the incidence of seizures following craniotomy?

18%

24

What is the drug of choice for postoperative seizure prophylaxis?

Phenytoin for 6 months

25

What is the relationship between the grade of malignancy of a glioma and the seizure risk?

Inverse! Lower grade a/w higher risk of seizure

26

DDx for seizures

Syncope (emotional, cardiac, postural, vasovagal), migraine (aura vs. partial seizure), pseudoseizures, movement disorders (Tourette's vs. myoclonic seizure)

27

What hormone is often elevated after seizures?

Prolactin

28

What is the chance of recurrence in a patient with first seizure?

78% in 3 years

29

Should you start an antiepileptic after 1st seizure?

Controversial; randomized studies say yes (esp. if structural lesion and early life onset)

30

AED after head injuries?

Decreases risk of early seizures (first 7 days) but not thereafter

Use phenytoin or carbamazepine