Seizures Flashcards
Approximately what proportion of patients with epilepsy have medically refractory seizures?
a. 0-20%
b. 20-40%
c. 40-60%
d. 60-80%
e. 80-100%
b. 20-40%
Which one of the following is a predictor of spontaneous epilepsy remission?
a. Abnormalities on neurological examination or developmental delay
b. Identification of epileptogenic substrate
c. Inadequate seizure control for greater
than 4 years
d. Persistent epileptiform abnormalities
on EEG
e. Younger age at onset
e. Younger age at onset
In general, predictors for low probability of epilepsy remission are (i) symptomatic localized epilepsy secondary to remote CNS injury, (ii) abnormalities on neurological examination or developmental delay, (iii) persistent epileptiform abnormalities on EEG, (iv) older age at onset, (v) inadequate control of seizures for longer than 4 years, (vi) presence of multiple seizure types and frequent generalized tonic-clonic seizures. Seizure duration of over 10 years also decreases likelihood of achieving seizure control in those who undergo epilepsy surgery.
The approximate rate of sudden unexpected death in epilepsy (SUDEP) in patients with medically intractable seizures is which one of the following?
a. 1 in 200 per year
b. 1 in 400 per year
c. 1 in 600 per year
d. 1 in 800 per year
e. 1 in 1000 per year
a. 1 in 200 per year
Overall rates of SUDEP in adults is 1 in 1000 and lower in children at 0.2-0.4 in 1000 per year. However, in adults and children with medically intractable epilepsy rates are higher at 1 in 100-200 per year. Cause of death in SUDEP is unclear but thought to be due to seizure related cardiac arrhythmias and/or respiratory compromise. The most reliable risk factor is severity and frequency of seizures (particularly generalized tonic-clonic seizures). Other risk factors include nocturnal seizures, young adult, poor adherence to treatment, earlier age of seizure onset, longer duration of epilepsy, symptomatic epilepsy and male gender.
A 7-year-old right-handed girl presented
with onset of seizures at 3-years old. Typically, her eyes rolled up and she often had
either a left or right body twitch. These
events lasted 10-12 s and occurred often in
activities such as eating or talking. Immediately after these seizures, she spontaneously
returned to her baseline. They typically
occurred 6-10 times a day. She had been on
numerous medications in the past but
continues to have frequent breakthrough
seizures on a daily basis. EEG shows a 3Hx spike and wave pattern. Which one of the following is most likely?
a. Breath holding attack
b. Cardiac syncope
c. Childhood absence epilepsy
d. Partial complex seizures
e. Rolandic epilepsy
c. Childhood absence epilepsy
A 12-year-old boy with diagnoses of attention-deficit disorder and hyperactivity was noted to have “staring episodes” beginning over 1 year before this evaluation. About 6 months earlier, the staring episodes became accompanied by some eye blinking and mouth twitching. He has had one generalized tonic-clonic seizure in the last year. Which one of the following is most likely diagnosis?
a. Childhood absence epilepsy
b. Day dreaming
c. Juvenile absence epilepsy
d. Neurocardiogenic syncope
e. Reflex anoxic seizure
c. Juvenile absence epilepsy
Juvenile absence epilepsy is a type of idiopathic
generalized epilepsy. Onset is from age 8 to
age 16 years, with a peak occurrence at 10-12
years of age. The frequency of absence seizures
in juvenile absence epilepsy is lower than that
in childhood absence epilepsy. A higher frequency of generalized tonic-clonic seizures is
seen compared with childhood absence epilepsy,
and there is an increased probability of epilepsy
continuing into the adult years. They also noted
that 11% of patients with the disorder report a
family history of epilepsy. Absence seizures are
predominant. The impairment of consciousness
in juvenile absence epilepsy is moderate and
not generally as severe as in childhood absence
epilepsy. The level of retained consciousness
may vary significantly from seizure to seizure
in the same patient. Unlike childhood absence
epilepsy they may occur once a day or in a cluster in the hour after awakening. The classic clinical feature is “simple absence” with staring and altered alertness (sometimes “complex absence” with blinking or head nodding). Seizures are typically triggered by hyperventilation or sleep deprivation. EEG: Interictal background activity is usual normal, spike and wave slightly faster (3.5-4 Hz).
A 19-year-old man presents with a history of seizures. The first was at age 12 when he got up very early in the morning to play computergames and was found by his mother a few hours later sitting at the computer blinking and unresponsive. Two years later he experiences a generalized tonic-clonic seizure. Currently he has a seizure every 1-3 weeks and can involve a minor jerk of the arms, staring with blinking, or generalized tonic-clonic seizures. He believed that sleep deprivation often precipitated seizures.Which one of the following is most likely diagnosis?
a. Benign familial convulsions
b. Benign myoclonic epilepsy in infancy
c. Epilepsy with myoclonic absences
d. Juvenile absence epilepsy
e. Juvenile myoclonic epilepsy
e. Juvenile myoclonic epilepsy
Juvenile myoclonic epilepsy comprises 5-10%. It is an idiopathic generalized epilepsy with myoclonic jerks; may also have typical absence seizures, generalized tonic-clonic seizures, or all three seizure types. The majority have myoclonic and generalized tonic-clonic seizures shortly after awakening from sleep. Seizure types have age-specific onset: absence (5-14 years), myoclonic (9-18 years), and generalized tonic-clonic seizures (9-26 years). Sleep deprivation is identified as a precipitating factor in the large majority (>90%) of individuals. The EEG showing paroxysmal spike, polyspike, and wave complexes that may be regular at 3-5 Hz but often are irregular with 2- to 10-Hz components. A photoconvulsive effect on the EEG has been described in at least one third of cases. Hyperventilation less reliably than in childhood absence epilepsy or juvenile absence epilepsy.
Which one of the following abnormalities is demonstrated in the ictal EEG below?
a. 3-Hz spike and wave discharge
b. Hypsarrhythmia
c. Lambda wave
d. Rhythmic temporal theta burst of bdrowsiness
e. Sleep spindles
a. 3-Hz spike and wave discharge
Which one of the following seizure types is classically associated with the pathology shown below?
a. Absence seizure
b. Complex partial seizure
c. Focal motor seizure
d. Gelastic seizure
e. Rolandic seizure
d. Gelastic seizure
Hypothalamic (or tuber cinereum) hamartomas are associated with gelastic seizures, visual problems, central precocious puberty (increased GnRH) and behavioral change. Gelastic seizures manifest as typically short (<30 s) bursts of uncontrollable laughter with preservation of consciousness.
Background interictal awake EEG in a 10-month-old female infant presenting with clusters of arm abduction and head drop. Which one of the following is most likely?
a. Benign Rolandic epilepsy
b. Gelastic epilepsy
c. Landau-Kleffner syndrome
d. Lennox-Gastaut syndrome
e. West syndrome
e. West syndrome
West syndromeis the triad of infantile spasms, hypsarrhythmia on EEG and developmental delay or regression. Onset is typically around 6 months of age (almost all begin within the first year of life); incidence is 1 in 3225 live births. Spasms may involve brief contractions of predominantly flexor or extensor muscle groups ranging from large “jack-knife” type motions to subtle head bobbing. These movements are at times difficult to differentiate from less serious non-epileptic events such as gastroesophageal reflux, colic and benign myoclonus of infancy. Precipitating factors mostly include when falling asleep/waking up, being handled, loud noise, feeding, infection, fever, excitement, hunger and excessive environmental temperatures. Cognitive disorders may include mental retardation, speech delay, autistic features and visuomotor dyspraxia. EEG of hypsarrhythmia consists typically of a diffuse, very high voltage, disorganized, chaotic and asynchronous pattern of multifocal spike and wave discharges. This pattern is seen while the child is both awake and in nonrapid-eye-movement (NREM) sleep. In REM sleep, there is marked reduction or even disappearance of the HA pattern. EEG with simultaneous pyridoxine injection is often performed to rule out pyridoxine-dependent seizures (very rare, <1 in 100,000; treatment is with high doses of vitamin B6). Video-EEG analysis is considered the gold standard to diagnose the spasms, and to assess for focal features of the spasm semiology or EEG tracings. Metabolic screens and LP may help identify cause. MRI should be done to look for surgical lesions. Adrenocorticotropic hormone (ACTH) is effective in the short-term treatment of infantile spasms and in the resolution of HA (takes about 2 weeks with an “all or nothing” response). Vigabatrin indicated for pediatric patients aged from 1 month to 2 years with infantile spasms (but risk of irreversible vision loss; need ophthalmology assessment). If EEG and MRI demonstrate a focal causative lesion surgical resection can be performed, while functional hemispherectomies may be used in more diffuse abnormalities (e.g. Sturge-Weber).
A 12-year-old, right-handed, developmentally delayed boy presented with three seizure types: generalized tonic-clonic, tonic, and atonic. The patient generally had at LEAST three brief seizures (1-10 s) per day of the tonic and atonic types but rarely had generalized seizures. He presented to the emergency department after one generalized tonic-clonic seizure followed by a series of atonic drop attacks concurrent with a streptococcal infection. The patient remained lethargic, and status epilepticus was a concern. Which of the following is the most likely diagnosis?
a. Aicardi syndrome
b. Angelman syndrome
c. Lennox-Gastaut syndrome
d. Otahara syndrome
e. West syndrome
c. Lennox-Gastaut syndrome
Lennox-Gastaut syndrome is characterized by multiple generalized seizure types that are refractory to treatment, cognitive dysfunction, and an interictal slow spike and wave pattern with a slow background on EEG. May be idiopathic or symptomatic (e.g. hypoxic-ischemic, traumatic brain injury). Onset is generally between 2 and 6 years of age. A wide range of behavioral problems will develop in about half of patients. Approximately 25% of patients will have a history of infantile spasms. The most common manifestation is a drop attack. Drop attacks may range from a simple head drop to a fall if proximal legs are involved. Because the drop attack may be due to a tonic, atonic, or myoclonic seizure, video-EEG monitoring may be necessary. Tonic seizures may involve the arms, legs, or whole body. Tonic seizures often occur in sleep. Atonic seizures appear as loss of postural tone of the head or whole body. Clonic (clusters of myoclonus) seizures involving the arms, face, or legs may occur in isolation or in clusters. The EEG shows a bisynchronous spike and wave or polyspikes and wave pattern. Sixty to seventy percent of patients exhibit atypical absence seizures. Hyperventilation does not provoke this seizure type. At least one episode of status epilepticus occurs in more than half of patients over their lifetime. Typical presentations include mental status changes or persistent tonic seizures. Medications are often chosen for the most debilitating seizure type. Broad-spectrum anticonvulsants such as valproic acid have been cited as good choices because of their efficacy in many seizure types. Surgical interventions including vagal nerve stimulator placement and corpus callosotomy have been used in some patients as palliative procedures with varying degrees of success. Lennox-Gestaut is one of the few epilepsies particullarily responsive to deep brain stimulation of the centromedian nucleus (Velasco et al.).
Which one of the following is the most common cause of neonatal seizures?
a. Fetal inflammatory response
b. Hypocalcemia
c. Hypoglycemia
d. Hypoxia-ischemia
e. Pyridoxine-dependent seizures
d. Hypoxia-ischemia
Hypoxia-ischemia (i.e. asphyxia) is traditionally considered the most common cause associated with neonatal seizures. Intrauterine factors before labor can result in fetal asphyxia without later documentation of acidosis at birth. Both antepartum and intrapartum maternal and placental illnesses associated with thrombophilia, preeclampsia, or specific uteroplacental abnormalities such as abruptio placentae or cord compression may contribute to fetal asphyxial stress leading to metabolic acidosis. Antepartum maternal trauma and chorioamnionitis are additional conditions that also contribute to the intrauterine asphyxia secondary to uteroplacental insufficiency. Intravascular placental thromboses and infarction of the placenta or umbilical cord documented after birth are markers for possible fetal asphyxia. Meconium passage into the amniotic fluid also promotes an inflammatory response within the placental membranes, potentially causing vasoconstriction and resultant asphyxia. Postnatal include persistent pulmonary hypertension of the newborn, cyanotic congenital
heart disease, sepsis, meningitis, encephalitis, and primary intracranial hemorrhage are leading diagnoses. Fetal inflammatory response may increase in the risk of unexplained early-onset seizures after intrapartum maternal fever. Other causes include hypoglycemia, hypocalcemia and pyridoxine-dependent epilepsy (rare).
Which one of the following is the likely origin of this secondarily generalized seizure recorded in the EEG below?
a. Frontal poles
b. Mesial temporal lobe
c. Motor cortex
d. Occipital
e. Parietal
a. Frontal poles
This ictal EEG begins with attenuation and then low-amplitude fast frequencies frontocentrally (Fp1-F3, Fp1-F7 and Fp2-F4, Fp2-F8) before evolving into more generalized irregular polyspike and wave
A 10-year-old right-handed boy presented with episodes of numbness around the mouth, drooling, right-sided facial twitching, and inability to speak on waking up from sleep. There was retained awareness and memory. Episodes were frequently followed by headaches. He experienced several episodes per week lasting up to 1-2 min. Sleep EEG shown below. Which one of the following is most likely?
a. Benign Rolandic epilepsy
b. Childhood absence epilepsy
c. Juvenile myoclonic epilepsy
d. Pyridoxine-dependent epilepsy
e. West syndrome
a. Benign Rolandic epilepsy
Benign focal epilepsy with centrotemporal spikes (BECTS; Benign Rolandic epilepsy) is the most frequent focal epilepsy syndrome in childhood. Age at onset ranges from 3 to 13 years of age, and peak incidence is usually around age 8 years. Seizures present usually at night, often shortly after falling asleep or before waking up. The present as somatosensory aura with perioral paresthesias, a sensation of choking, and jaw or tongue stiffness. Hemifacial or hemibody motor seizures, frequently with unilateral clonic, but also tonic or tonic-clonic, activity are seen in up to 34% of patients. Motor features involve the face, lips, tongue, pharynx, and larynx, and this may be associated with speech arrest. Generalized tonic-clonic seizures without focal onset have been described in 54%. The characteristic interictal EEG finding is a distinct high-amplitude, diphasic spike with prominent aftergoing slow wave typically in C3/C4 or T3/T4 electrodes. Spikes are more frequently observed during sleep, and sleep activation of spikes is a salient feature of BECTS. The condition remits spontaneously in almost all patients around the age of 16 years hence indications for treatment include seizures during daytime, repeated generalized tonic-clonic seizures, prolonged seizures, and status epilepticus as well as seizure onset before the age of 4 years. Carbamazepine may control seizures in up to 65% of patients.
A 54-year-old has been experiencing three types of odd episodes for the last few years. The first type involves a wave of non-painful sensation emanating from the left elbow up and down herleft arm and then progressing with “electricity” pain marching into her neck and head. This could evolve into a more severe second type of seizure in which the left side became very painful and she felt afraid, had difficulty breathing, and then had clonic activity of the left face and arm with loss of awareness (about 2 per month). The third type was a “hyperawareness” in which she knew something was going to happen and objects looked larger. Which one of the following is most likely?
a. Absence seizures
b. Frontal seizures
c. Mesial temporal lobe seizures
d. Occipital seizures
e. Parietal seizures
e. Parietal seizures
Parietallobe seizures areinfrequent in bothmedical and surgical cases, representing from 4.4% to 6% of all epilepsies. The etiology of parietal lobe seizures has a strong association with space-occupying lesions, which may include tumors, congenital anomalies, postinflammatory brain scarring, and vascular lesions. As a group, parietal lobe seizures are usually suspected by somatosensory symptomatology at onset. All sensory modalities may be experienced, and often more than one type is perceivedin each seizure.The twomost commonmanifestations include paresthetic seizures and painful seizures. Elementary paresthesia is the most common somatosensory perception in seizures. These most commonly are reported as tingling and/or numbness. Other descriptions may be pins and needles, prickling, or a crawling under the skin. Sensation usually starts in a segment of the limb, usually distal, and then spreads toinvolve thewhole extremity in a march-like fashion. Painful seizures are usually experienced in conjunction with other sensory perceptions. They are described as severe, stabbing, throbbing, or cramp-like. The hands are most commonly involved, especially distal, followed by the head, face, and legs.
Less frequent somatosensory seizures of parietal lobe origin include thermal perception, sexual seizures, ideomotor apraxia, and disturbances of
body image. Tonic posturing, clonic activity, contralateral version, and hypermotor activity may characterize subsequent spread of the ictal
focus to the frontal lobe. If the focus spreads to the temporal lobes it produces automatism and alteration of consciousness. Posterior seizure spread results in visual auras.
A 24-year-old female presented with a history of severe migraines as a child associated with nausea and vomiting. She continued to have seizures beginning with flashing lights and colors in the left visual field followed by amaurosis and loss of awareness that might be associated with fumbling automatisms and lip smacking. Which one of the following is most likely?
a. Mesial temporal sclerosis
b. Occipital cortical dysgenesis
c. Parietal meningioma
d. Subependymal giant cell astrocytoma
e. Third ventricular colloid cyst
b. Occipital cortical dysgenesis
Occipital lobe epilepsies are uncommon (5%) and identified by the presence of visual phenomena in the early seizure symptoms. In patients with seizures arising from the medial occipital lobe, visual field deficit can be found in 20-40%. The vision loss often is unnoticed by the patient, may be subtle enough to be missed on confrontational testing as part of the neurologic examination, and may require formal visual field testing to be appreciated. The most common auras are simple visual hallucinations (white or colored lights that can be constant, flashing, stationary or moving). Ictal blurring or amaurosis (blindness) is reported in 25-40% of case series and can be described as either a whiteout or blackout. When propagation is infrasylvian and lateral to the temporoparietal
visual association areas, complex visual hallucinations and illusions (achromatopsia, micro/macropsia, metamorphopsia, micro/macroproxiopia, or palinopsia) may occur. In contrast, propagation to the mesial temporal lobe may result in reports of rising epigastric sensation, smells, and nausea and complex partial seizures. Suprasylvian parietal spread may lead to reports of somatosensory phenomena such as paresthesias and vertigo. Spread from the occipital lobes may evolve to complex partial seizures typical of temporal origin with prominent oral and gestural automatisms, to lateral frontal lobe with clonic motor activity, or to
mesial frontal lobe with tonic seizure manifestations typical of supplementary motor seizures. Apart from focal lesions occipital seizures also occur as part of neurodegenerative disorders such as the progressive myoclonic epilepsies (LaFora body disease, ceroid lipofuscinosis), mitochondrial disorders (MERRF and MELAS) and posterior reversible leukoencephalopathy syndrome.
