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Flashcards in epilepsy and seizures Deck (22):
1

A 9-year-old boy is brought to your clinic by his parents because he has begun to have episodes of eye fluttering lasting several seconds. Sometimes he loses track of his thoughts in the middle of a sentence. There was one fall off a bicycle that may have been related to one of these events. There are no
other associated symptoms, and the episodes may occur up to 20 or more times per day. The boy’s development and health have been normal up until this point. He did have two head injuries as a young child: the first when he fell off a tricycle onto the ground, and the second when he fell off of a play- set onto his head. Both episodes resulted in a brief loss of consciousness and he did not think clearly for part of the day afterward, but had no medical
intervention. The test most likely to confirm this patient’s diagnosis is
a. Brain CT scan
b. Brain MRI
c. Electroencephalogram
d. Lumbar puncture
e. Nerve conduction study

The answer is c. ( Victor, p 335.) This is a common presentation for primary generalized epilepsy of childhood. An electroencephalogram showing the classic 3-Hz spike-and-wave pattern would confirm this diag-nosis. Brain MRI and CT are useful for evaluating brain anatomy. Anatomic problems can cause seizures, but these tests will not tell anything about brain electrical activity. Lumbar puncture is useful for measuring cere-brospinal fluid pressure and looking for central nervous system inflamma-tion or infection. Central nervous system inflammation or infection may
cause seizures. Nerve conduction study is useful to evaluate peripheral nerve injuries such as nerve entrapment

2

A 19-year-old right-handed man who carries the diagnosis of epilepsy is seen in the urgent care clinic. He had been healthy until about age 12, when he began to have episodes of eye fluttering lasting several seconds.
Sometimes he would lose track of his thoughts in the middle of a sentence. There was one fall off of a bicycle that may have been related to one of these events. He has been treated with valproic acid. At one point he was off all
medications, but the seizures returned. He is now at the end of his first semester of college and comes in today because he had a witnessed gener-alized tonic-clonic seizure this morning. He had only had about 2 h of sleep the night before because he was studying for a final exam. The most appropriate thing to tell this patient would be
a. “I know that you faked this seizure to avoid taking a test.”
b. “Lack of sleep may have contributed to triggering this seizure.”
c. “You can expect to have tonic-clonic seizures on a regular basis from now on.”
d. “Your seizures are getting worse and there is nothing we can do about it.”
e. “You should take the next semester off to recover and get extensive testing.”

The answer is b.( Bradley, p 1803.) Lack of sleep is a common seizure trigger. There is no reason to believe that the patient faked the seizure. It is impossible to predict his future seizure course based on this one event; hav-ing one seizure does not necessarily mean that his seizures are getting worse, and even if they are there are many treatments available. There is no reason for the patient to take a prolonged leave of absence from school because of
one seizure. This may even have detrimental psychological consequences

3

A 56-year-old man with epilepsy is brought into the emergency room. He has been having continuous generalized tonic-clonic seizures for the past 30 min. He is treated with 2 mg of intravenous lorazepam. Most physi-cians recommend using a high dose of intravenous benzodiazepine as part of the management of status epilepticus because of its
a. Ability to suppress seizure activity for more than 24 h after one injection
b. Lack of respiratory depressant action
c. Rapid onset of action after intravenous administration
d. Lack of hypotensive effects
e. Lack of dependence on hepatic function for its metabolism and clearance

The answer is c. ( Bradley, pp 1760–1761.) Until recently, the most popular benzodiazepine for use in status epilepticus was diazepam (Val-ium), which has a rapid onset of action but is cleared relatively quickly.
Because of this property, patients needed additional medications, such as phenytoin, to protect them from recurrent seizure activity as early as 20 min after diazepam injection. A longer-acting benzodiazepine, lorazepam
(Ativan), has the advantage of being rapid-acting like diazepam but being cleared more slowly from the body.

4

he patient’s seizing does not stop. A second intravenous drug is given. Infusing which of the following antiepileptic drugs at more than 50 mg/min in an adult may evoke a cardiac arrhythmia?
a. Carbamazepine
b. Diazepam
c. Phenobarbital
d. Clonazepam
e. Phenytoin

The answer is e.( Bradley, p 1761.) Rapid infusion of phenytoin may produce a conduction block or other basis for cardiac arrhythmia. Pheny-toin should not be administered at rates greater than 50 mg/min in adults or 1 mg/(kg min) in children to reduce the chances of this reaction occurring.
Thus, it usually requires approximately 20 min to administer a 1000- to 1500-mg standard loading dose of phenytoin in an emergent setting such as status epilepticus. Fosphenytoin, a water-soluble prodrug of phenytoin that has recently become available, has the advantage of causing fewer infusion
site reactions. It can be given at doses of up to 150 mg/min in an adult, with risks of cardiac dysrhythmia similar to those of phenytoin. Another advan-tage of fosphenytoin is that it can be administered intramuscularly when
intravenous access is problematic. Carbamazepine is not administered intra-venously at all. Rapid infusion of phenobarbital may produce hypotension or respiratory arrest, but is much less likely to depress cardiac activity. Diazepam and clonazepam are safer than phenobarbital, but rapid infusion
of excessively high doses may depress blood pressure and other autonomic functions

5

A 44-year-old man presents with left arm shaking. Two days ago, the patient noted left arm paresthesias along the lateral aspect of his left arm and left fourth and fifth fingers while he was reading. He thinks he may have been
leaning on his left arm at the time; the symptoms resolved after 30 s. This morning, he noted the same feelings, lasting a few seconds, but then his 4th and 5th fingers started shaking rhythmically, and the shaking then migrated
to all his fingers, his hand, and then his arm up to his elbow. This episode lasted a total of 30 s. He denies any strange smells or tastes, visual changes, or weakness. Afterward, his fingers felt locked in position for a few seconds.
Then he felt as if he did not have control of his hand and had difficulty don-ning his socks. He and his wife decided to drive to emergency room, and in the car he had trouble putting his seat belt latch into its socket. Examination
and routine labs are normal. The next most appropriate action would be to
a. Discharge the patient to follow up in clinic in 2 weeks
b. Obtain a brain MRI
c. Obtain an electroencephalogram
d. Obtain an orthopedic consult
e. Order electromyography and nerve conduction studies

The answer is b. (Greenberg, 5/e, p 267.) This history is typical of a simple partial seizure. A focal brain lesion must be ruled out. It would be
wrong to discharge the patient to follow up in clinic in 2 weeks without at least a CT scan and preferably an MRI. Although he probably had a seizure, obtaining an electroencephalogram at this point will not be as helpful as an MRI. This is unlikely to be a peripheral nerve problem, and therefore an orthopedic consult or electromyography and nerve conduction studies are not indicated

6

A 31-year-old right-handed woman has a history of alcohol abuse requiring detox. Currently, she says she is drinking about nine beers 3 days per week. She drank five glasses of wine and 3 beers 5 days ago, and she had
10 beers last night. This morning, she awoke feeling well. She was speaking with her fiancé, went to the bathroom, and got back into bed. She had no headache, fever, chills, nausea, vomiting, or pain. Suddenly her body became
stiff with arms flexed for a few seconds, followed by rhythmic jerking of both arms. Her legs were shaking, but less so. Her eyes were open, and she was foaming at the mouth. After 1 min, this stopped, and she initially did not
recognize her fiancé or his sister. She slowly returned to a normal level of consciousness over a 10-min period. She remembers events just prior to the episode, and she remembers being in the car on the way to the hospital. Her
only medication is a multivitamin. She denies illicit drugs. Her examination is entirely normal. Routine labs and a brain MRI are normal. The most likely underlying cause of her condition is
a. Autoimmune
b. Genetic
c. Infectious
d. Neoplastic
e. Toxic/metabolic

The answer is e. (Greenberg, 5/e, p 12.) This is a typical example of alcohol withdrawal seizure. The greatest risk for alcohol withdrawal seizures occurs within the first day after drinking cessation, in contrast to delirium tremens, which usually occurs within 2 to 4 days of drinking ces-sation. There is no evidence of an autoimmune process in this patient. Ras-mussen encephalitis is an example of a seizure disorder thought to be of
autoimmune etiology. There are many examples of genetically transmitted
epilepsies, which usually present during childhood. Infections such as meningitis, brain abscess, or encephalitis can cause seizures. Signs of these include meningeal signs, fever, and MRI findings. If this patient had a brain
tumor, you might expect a history of headache due to increased intracra-nial pressure. Additionally, the exam and MRI would likely be abnormal.

7

A 4-year-old boy has the onset of episodes of loss of body tone, with associated falls, as well as generalized tonic-clonic seizures. His cognitive function has been deteriorating. EEG shows 1.5- to 2-Hz spike-and-wave discharges. The most likely diagnosis is
a. Landau-Kleffner syndrome
b. Lennox-Gastaut syndrome
c. Juvenile myoclonic epilepsy
d. Mitochondrial encephalomyopathy
e. Febrile seizures

The answer is b. ( Bradley, p 1758.) Lennox-Gastaut syndrome is a disturbance seen in children. It is often difficult to control the seizures that develop in children with this combination of retardation and slow spike-and-wave discharges on EEG. Many affected children have a history of infantile spasms (West syndrome). Infants and children with infantile spasms exhibit paroxysmal flexions of the body, waist, or neck and usually have a profoundly disorganized EEG pattern called hypsarrhythmia.

8

A 27-year-old man begins to experience infrequent episodes of nausea, warmth rising through his body, and an unusual odor like rotting fish. His girlfriend notices that afterward he may develop twitching of the left side of
his face and an inability to speak for several minutes. Afterward the man appears dazed and cannot remember what has occurred. He has otherwise been well. Magnetic resonance imaging (MRI) of his brain is most likely to show a lesion in which area of the brain?
a. Left frontal lobe
b. Right frontal lobe
c. Cribriform plate
d. Uncus
e. Left parietal lobe

The answer is d.( Victor, p 338.) Many patients with complex partial seizures have a preseizure phenomenon (the aura) that alerts them to an
impending seizure. This patient’s aura includes an olfactory hallucination, which is usually associated with lesions of the mesial temporal lobe, par-ticularly the uncus or parahippocampal gyrus. Diseases that can affect that region include tumors, trauma, and mesial temporal sclerosis.

9

An 18-year-old girl riding on the back of her boyfriend’s motorcycle without a helmet is brought in with a left frontal skull fracture and corticalcontusion. GCS is 10. She is admitted to the intensive care unit. She has had no seizures. Anticonvulsant therapy is
a. Contraindicated due to risk of rash
b. Best achieved using phenobarbital
c. Likely to cause increased cerebral edema
d. Indicated to reduce the incidence of late posttraumatic epilepsy
e. Indicated to reduce the incidence of early posttraumatic seizures

The answer is e.( Bradley, p 1076.) There is evidence that prophylac-tic phenytoin reduces the incidence of seizures after head injury from
14.2% to 3.6%. Because early posttraumatic seizures may lead to increased morbidity and prolonged hospital stays, it is reasonable in some situations to treat patients prophylactically. There is no evidence that prophylactic treatment reduces the long-term risk of developing posttraumatic epilepsy,
though many neurosurgeons treat patients with more severe injuries.

10

A patient with intractable complex partial seizures due to cortical dys-plasia undergoes left temporal lobectomy. He is most likely to develop
which of the following problems after surgery?
a. Right superior quadrantanopsia
b. Right inferior quadrantanopsia
c. Right homonymous hemianopsia
d. Right hand weakness
e. Aphasia

The answer is a. (Patten, p 25.) The most common complication of
temporal lobectomy is a visual field defect due to interruption of fibers
from the optic tracts passing over the temporal horn of the lateral ventri-cles. Superior quadrantanopsia is more common than hemianopsia. Some
deficits may improve if the injury does not completely damage the nerves.
Language deficits, particularly dysnomia, occur less frequently. Hemipare-sis is uncommon ( <2%), because the surgery is performed at a distance
from the motor fibers of the corticospinal tract. Other neurological prob-lems that can occur include diplopia due to extraocular nerve deficits, and
facial paresis.

11

A 37-year-old man develops involuntary twitching movements in his left thumb. Within 30 s, he notices that the twitching has spread to his entire left hand and that involuntary movements have developed in his left forearm and the left side of his face. He cannot recall what happened sub-sequently, but his wife reports that he fell down and the entire left side of his body appeared to be twitching. He appeared to be unresponsive for about 3 min and confused for another 15 min. During the episode, he bit his tongue and wet his pants. (SELECT 1 SEIZURE TYPE)
a. Generalized tonic-clonic
b. Generalized absence
c. Complex partial
d. Epilepsia partialis continua
e. Simple partial sensory
f. Jacksonian march
g. Psychomotor status
h. Tonic-clonic status epilepticus
i. Pseudoseizures
j. Myoclonic

The answer is f.( Victor, pp 337–338.) With a Jacksonian march, or sequential seizure, the patient develops focal seizure activity that is pri-marily motor and spreads. This type of seizure often secondarily general-izes, at which point the patient loses consciousness and may have a generalized tonic-clonic seizure. The hand is a common site for the start of a Jacksonian march. The face may be involved early because the thumb and the mouth are situated near each other on the motor strip of the cere-bral cortex

12

A 17-year-old boy reports involuntary jerking movements in his arms when he awakened. This occurred during the day after a nap, as well as in the morning after a full night’s sleep. Over the next few months, he devel-oped similar jerks during the day even when he had been awake for several hours. He did not lose consciousness with these muscle jerks, but did occa-sionally fall. On one occasion, jerks in his legs resulted in a fall during which he fractured his wrist. (SELECT 1 SEIZURE TYPE)
a. Generalized tonic-clonic
b. Generalized absence
c. Complex partial
d. Epilepsia partialis continua
e. Simple partial sensory
f. Jacksonian march
g. Psychomotor status
h. Tonic-clonic status epilepticus
i. Pseudoseizures
j. Myoclonic

The answer is j.( Victor, p 109.) Myoclonic seizures may be general-ized or partial. They are most commonly seen in the epilepsy syndrome called benign juvenile myoclonic epilepsy (BJME). Unlike sleep myoclonus,
the episodes occur when the affected person wakes up, rather than when he or she is falling asleep. Myoclonic jerks may be triggered by light flashes or loud sounds. Benign juvenile myoclonic epilepsy accounts for 4% of all
cases of epilepsy. More than half of those with BJME have generalized tonic-clonic seizures as well as myoclonic seizures.

13

A 21-year-old man reports several episodes over the previous 4 years during which he lost consciousness. He had no warning of the impending episodes, and with each episode he injured himself. Observers told him that he abruptly developed a blank stare and stopped talking. His body became stiff and he arched his back. After several seconds of this type of
posturing, his arms and legs started shaking violently. During one of these episodes, he dislocated his right shoulder. He routinely bit his tongue and urinated in his pants during the episodes. (SELECT 1 SEIZURE TYPE)
a. Generalized tonic-clonic
b. Generalized absence
c. Complex partial
d. Epilepsia partialis continua
e. Simple partial sensory
f. Jacksonian march
g. Psychomotor status
h. Tonic-clonic status epilepticus
i. Pseudoseizures
j. Myoclonic

The answer is a.( Victor, pp 333–334.) With generalized tonic-clonicseizures, the EEG develops abnormalities all over the cortex simultane-ously. The patient may recall a strange sensation before the attack, but it is
equally likely that no premonitory sign or aura will occur. Partial seizures may secondarily generalize to this type of seizure. If the patient has fre-quent generalized tonic-clonic seizures, he or she will be at high risk for a variety of injuries, such as dislocated shoulders, broken bones, and head trauma. Patients with this type of seizure always lose consciousness during the attack and may be confused for minutes or hours after the ictus, the most obvious segment of the seizure

14

A 25-year-old woman was fired from her job after she misplaced papers vital for the company. She had had recurrent episodes for several years dur-ing which she performed nonsensical activities such as burying her plates in the backyard, hiding her underwear, and discarding her checkbook. She did not recall what she had done after performing these peculiar activities. She had been referred for psychotherapy, but the episodes only became more fre-quent after she was started on thioridazine (Mellaril). Her husband observed one episode and noted that she was unresponsive for about 5 min and con-fused for at least 1 h. She did not fall down or remain immobile during the episodes. As the episodes became more frequent, she noticed that she would develop an unpleasant taste in her mouth, reminiscent of motor oil, just before an episode. (SELECT 1 SEIZURE TYPE)
a. Generalized tonic-clonic
b. Generalized absence
c. Complex partial
d. Epilepsia partialis continua
e. Simple partial sensory
f. Jacksonian march
g. Psychomotor status
h. Tonic-clonic status epilepticus
i. Pseudoseizures
j. Myoclonic

The answer is c.( Victor, pp 339–342.) Complex partial seizures may be mistaken for a psychiatric problem, especially if the partial seizures do not generalize and produce tonic-clonic seizures. This patient has a typical
aura involving an unpleasant smell or taste. These were once called unci-nate fits, because they were ascribed to abnormal activity in the uncus of the temporal lobe. Complex partial seizures may arise from a focus of abnormal electrical activity in the temporal lobe, but they do not invariably arise from a temporal lobe focus

15

A 21-year-old cocaine-abusing man develops seizures that persist for more than 30 min before emergency medical attention is available. When examined nearly 1 h later, he is still exhibiting tonic-clonic movements and
has never recovered consciousness. (SELECT 1 SEIZURE TYPE)
a. Generalized tonic-clonic
b. Generalized absence
c. Complex partial
d. Epilepsia partialis continua
e. Simple partial sensory
f. Jacksonian march
g. Psychomotor status
h. Tonic-clonic status epilepticus
i. Pseudoseizures
j. Myoclonic

The answer is h.( Bradley, pp 1759–1760.) Status epilepticus is defined as a seizure that lasts continuously for 30 min or a series of seizures over a 30-min period without the patient’s regaining full consciousness between them. Status constitutes a medical emergency, because the longer the seizures last, the worse are morbidity and mortality. Complications of status include respiratory failure, aspiration, acidosis, hypotension, rhab-domyolysis, renal failure, and cognitive impairment

16

A 16-year-old boy with a history of acute viral myocarditis requires placement of a left ventricular assist device. He has a complicated postop-erative course, with fever, bacteremia, and renal failure. On postoperative day 10, he develops continuous rhythmic jerking of the left corner of the mouth, associated with jerking of the left thumb. This persists for 24 h. He
is alert, able to follow commands, and has no gaze deviation. Computed tomography shows a small hemorrhagic infarction of the right posterior frontal region. (SELECT 1 SEIZURE TYPE)
a. Generalized tonic-clonic
b. Generalized absence
c. Complex partial
d. Epilepsia partialis continua
e. Simple partial sensory
f. Jacksonian march
g. Psychomotor status
h. Tonic-clonic status epilepticus
i. Pseudoseizures
j. Myoclonic

The answer is d. ( Victor, pp 343–344.) Epilepsia partialis continua refers to a condition of persistent focal motor seizure activity—in essence, a focal motor status epilepticus. The distal hand and foot muscles are most frequently affected. Active or passive movement of the limb may exacerbate the seizure activity. The seizures may persist for hours to months. The response to therapy is often poor

17

A 19-year-old woman complains of recurrent memory problems. Her fiancé reports that she seems to be inattentive for minutes at a time, several times a week. She never injures herself during these episodes, but she can-not recall what happened, and, on one occasion, she became lost while walking home. An ambulatory EEG demonstrates spike–and–slow wave activity originating in the left temporal lobe during one of the episodes. The EEG pattern does not generalize. Computed tomography and MRI scanning of the brain reveal no structural abnormalities. Conversations
with the woman’s parents reveal that she had febrile seizures when she was 3 years old, which abated with antipyretic treatment alone. (SELECT 1 DRUG)

The answer is f.( Victor, pp 356–360.) This young woman is having complex partial seizures without secondary generalization. She has episodic altered consciousness associated with a temporal lobe seizure focus and ante-dated by febrile seizures. Carbamazepine is the drug of choice because of its relatively good adverse effect profile in persons in this age group. Phenytoin is another reasonable option, but carries with it the adverse effects of hir-sutism and gingival hypertrophy, often considered undesirable in a young woman. Because she is of childbearing age, the patient has the additional problem of a slightly increased risk of birth defects in her offspring. However, the risk to the fetus from seizure activity is probably greater than that from
exposure to an antiepileptic drug

18

A 7-month-old boy develops generalized limb extension and neck flex-ion spasms that occur more than 20 times daily and are associated with
altered consciousness. EEG reveals diffuse, high-voltage polyspike–and–slow
wave discharges between spasms and suppression of these bursts during the
spasms. A sibling died with a brainstem glioma, and the father has several
large areas of hypopigmented skin in the shape of ash leaves. The infant had
obvious psychomotor retardation even before the appearance of the spasms.
(SELECT 1 DRUG)

The answer is k.( Victor, p 342.) This child has West syndrome, a gen-eralized seizure disorder of infants characterized by recurrent spasms, the
EEG pattern of hypsarrhythmia, and retardation. Several different diseases
cause West syndrome. The family history in this case suggests tuberous
sclerosis as the underlying problem. Adrenocorticotropic hormone is cur-rently the only medication accepted as substantially affecting these infantile
spasm

19

A 5-year-old girl has frequent staring spells and does not respond to her mother’s calling her name during these episodes. She never falls down or bites her tongue, but she does have occasional lip smacking during episodes. EEG reveals a 3/s (Hz) spike-and-wave pattern that occurs for less than 10 s at a time but several times an hour. The child has normal motor and cogni-tive development. (SELECT 2 DRUGS

The answers are g and h. ( Victor, p 360.) This girl has generalized absence attacks. This may be a manifestation of a more complex epilepsy
syndrome or may occur as an isolated finding. Generalized absence attacks have no aura and no postictal period. The affected child has no warning that an attack is about to occur and is usually unaware that one has occurred unless it is more than a few seconds long. In fact, generalized absence seizures are most often only a few seconds long. Ethosuximide is the drug of choice, but it may cause gastrointestinal distress. Divalproex sodium is effective in many of the children who cannot tolerate ethosux-imide or who are not well controlled on that antiepileptic. If the absence
seizures are associated with generalized tonic-clonic seizures, divalproex sodium is a better choice

20

A 35-year-old pregnant woman at term is admitted to the hospital for delivery. She complains of headaches and visual blurring. Her blood pres-sure is 180/100. On examination she is edematous. Reflexes are increased. Protein is found in the urine. She then develops a generalized tonic-clonic
convulsion. (SELECT 1 DRUG

The answer is b. ( Rowland, p 918.) Recent studies have established that magnesium sulfate (MgSO4) is the optimal treatment both to prevent seizures in women with hypertension at the time of admission for delivery (preeclampsia) and to treat seizures in established eclampsia. The dose is 4 to 5 g intravenously, followed by a 1-g/h intravenous infusion. Magnesium sulfate was shown to result in a reduction in recurrent seizures and in
maternal morbidity and mortality compared with both diazepam and phenytoin. In addition, the fetus should be delivered as quickly as possible, using C-section if necessary

21

A 35-year-old pregnant woman at term is admitted to the hospital for delivery. She complains of headaches and visual blurring. Her blood pres-sure is 180/100. On examination she is edematous. Reflexes are increased. Protein is found in the urine. She then develops a generalized tonic-clonic convulsion. (SELECT 1 DRUG

The answer is b. ( Rowland, p 918.) Recent studies have established that magnesium sulfate (MgSO4) is the optimal treatment both to prevent seizures in women with hypertension at the time of admission for delivery (preeclampsia) and to treat seizures in established eclampsia. The dose is 4 to 5 g intravenously, followed by a 1-g/h intravenous infusion. Magnesium sulfate was shown to result in a reduction in recurrent seizures and in
maternal morbidity and mortality compared with both diazepam and phenytoin. In addition, the fetus should be delivered as quickly as possible, using C-section if necessary

22

A 9-year-old boy is brought to your clinic by his parents because he has begun to have episodes of eye fluttering lasting several seconds. Sometimes he loses track of his thoughts in the middle of a sentence. There was one fall off a bicycle that may have been related to one of these events. There are no
other associated symptoms, and the episodes may occur up to 20 or more times per day. The boy’s development and health have been normal up until this point. He did have two head injuries as a young child: the first when he fell off a tricycle onto the ground, and the second when he fell off of a play-set onto his head. Both episodes resulted in a brief loss of consciousness and he did not think clearly for part of the day afterward, but had no medical
intervention. The test most likely to confirm this patient’s diagnosis is
a. Brain CT scan
b. Brain MRI
c. Electroencephalogram
d. Lumbar puncture
e. Nerve conduction study

The answer is c. ( Victor, p 335.) This is a common presentation for primary generalized epilepsy of childhood. An electroencephalogram showing the classic 3-Hz spike-and-wave pattern would confirm this diag-nosis. Brain MRI and CT are useful for evaluating brain anatomy. Anatomic problems can cause seizures, but these tests will not tell anything about brain electrical activity. Lumbar puncture is useful for measuring cere-brospinal fluid pressure and looking for central nervous system inflamma-tion or infection. Central nervous system inflammation or infection may
cause seizures. Nerve conduction study is useful to evaluate peripheral nerve injuries such as nerve entrapment