Questions and Answers
What imaging techniques are commonly used for detecting malignancy?
Elevated creatinine kinase (CK) levels are indicative of muscle damage due to seizures.
True
What specific antibody testing might be considered in the evaluation of encephalitis?
Autoimmune antibody testing
Paroxysmal elevated ____ levels may indicate lactic acidosis due to metabolic demand during seizures.
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Match the following laboratory tests to their implications regarding seizures:
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What test might be conducted to assess thyroid function in metabolic evaluations?
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Genetic testing is not considered necessary for hereditary seizure disorders.
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What management might be needed for eclamptic seizures in pregnant individuals?
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A review of medication lists is essential for identifying ____ related seizures.
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Which condition relies on assessing glucose and electrolyte levels in the metabolic evaluation?
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Which of the following drugs are known to lower seizure threshold?
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Eclampsia is only associated with non-pregnant individuals experiencing seizures.
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What is the term for the pre-seizure sensation experienced prior to a seizure?
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Focal seizures can occur in a specific __________ of the brain.
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Match the following seizure types with their characteristics:
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Which lobe is primarily affected by auditory sensations during focal seizures?
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The post-ictal phase is marked by full cognitive clarity and alertness.
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What types of seizures can secondarily generalize from focal seizures?
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The __________ seizure is characterized by involuntary staring and does not involve loss of muscle tone.
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What is the recommended action if anti-epileptic drug (AED) levels are low?
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Which of the following conditions is categorized as a vascular cause of seizures?
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Epilepsy is defined by a single unprovoked seizure with at least a 60% chance of recurrence.
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What is a common metabolic cause of seizures?
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Seizures result from abnormal, excessive synchronous electrical activity in the central nervous system, leading to __________ features.
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Match the following causes of seizures to their respective types:
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Which of these conditions is associated with the risk of seizures due to autoimmune causes?
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Subdural hematoma is characterized by a lens-shaped bleed.
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What is the mnemonic used to remember the causes of seizures?
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Recurrent unprovoked seizures occurring greater than 24 hours apart define __________.
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Which metabolic abnormality, due to kidney dysfunction, can lead to seizures?
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Which of the following seizures typically involves loss of consciousness?
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Eclampsia is associated with seizures in non-pregnant individuals.
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What is characterized by involuntary staring episodes with no loss of muscle tone?
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Focal seizures can _______ generalize to become generalized seizures.
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Match the seizure types with their characteristics:
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Which neurotransmitter's dysfunction leads to decreased inhibitory potential in seizures?
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The post-ictal phase is characterized by confusion and lethargy.
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What type of seizure is characterized by a distal-to-proximal spread of movements?
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The electrical activity affecting the ______ lobe can cause auditory sensations.
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Which of the following is a significant drug-related cause of seizures?
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Which of the following is NOT considered a metabolic cause of seizures?
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Epilepsy is characterized by recurrent unprovoked seizures, defined as one seizure occurring greater than 24 hours apart.
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Name one infectious cause of seizures.
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A seizure may include various clinical features such as __________ or __________ seizures.
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Match the following causes of seizures with their respective types:
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What is the primary clinical feature of a focal seizure?
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Hypertensive encephalopathy can be associated with seizures.
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What mnemonic is used to remember the causes of seizures?
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The type of seizure characterized by involuntary staring is known as __________ seizure.
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Which of the following conditions is a cause of traumatic seizures?
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Which of the following tests can indicate muscle damage associated with severe seizures?
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Elevated prolactin levels can indicate seizures rather than psychogenic non-epileptic events.
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What imaging techniques are utilized for detecting structural injuries associated with trauma?
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Elevated __________ levels may indicate lactic acidosis from metabolic demand during seizures.
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Match the following causes of seizures with their implications:
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Which of the following conditions might warrant a review of medication lists and toxicology screening?
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Eclamptic seizures are only associated with high blood pressure in pregnant individuals.
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What laboratory test is elevated in cases of rhabdomyolysis due to prolonged seizures?
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__________ testing may be considered for hereditary seizure disorders.
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Which of the following might be indicated in evaluating a patient for metabolic causes of seizures?
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Which of the following is considered a traumatic cause of seizures?
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A generalized seizure is defined as a seizure affecting only one hemisphere of the brain.
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What is the main characteristic of epilepsy?
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A common infectious cause of seizures is __________.
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Match the following types of seizures with their definitions:
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Which of the following is NOT a metabolic cause of seizures?
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Autoimmune causes of seizures include antibody-mediated encephalitis.
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What mnemonic can be used to remember the causes of seizures?
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Seizures are caused by abnormal, excessive __________ activity in the central nervous system.
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What type of metabolic abnormality can lead to seizures due to kidney dysfunction?
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Which laboratory test is commonly elevated in cases of rhabdomyolysis due to prolonged seizures?
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Lactate levels may indicate metabolic demand during seizures.
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What is the metabolic test used to assess electrolyte levels and thyroid function?
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Elevated levels of __________ in a patient may indicate seizures rather than psychogenic non-epileptic events.
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Match the following laboratory tests with their implications:
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Which imaging technique is primarily used for the detection of malignancy in patients with seizures?
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Eclamptic seizures are primarily associated with low blood pressure in pregnant individuals.
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Genetic testing may be considered for __________ seizure disorders.
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What test might be needed in managing eclamptic seizures?
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What type of seizures may indicate a drug-related cause?
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What type of seizure is characterized by a loss of consciousness and may involve automatisms?
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Tonic-clonic seizures are classified as non-motor seizures.
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What neurotransmitter is decreased in inhibitory transmission during seizures?
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The primary area of the brain affected in __________ seizures is limited to one hemisphere.
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Match the type of seizure with its characteristic:
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What is a common symptom during the post-ictal phase?
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Focal seizures can become generalized through a process known as secondary generalization.
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What characteristic EEG pattern is observed in absence seizures?
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Eclampsia is primarily associated with __________ individuals and high blood pressure.
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Which type of seizure typically does NOT involve a post-ictal state?
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What is a characteristic feature of seizures?
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Two or more unprovoked seizures occurring less than 24 hours apart define epilepsy.
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Name one common vascular cause of seizures.
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The __________ is characterized by inflammation of the brain tissue and can lead to seizures.
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Which of the following is NOT a metabolic cause of seizures?
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Match the following causes of seizures with their respective types:
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Hypertensive encephalopathy is associated with seizures.
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What is the mnemonic used to remember the causes of seizures?
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Seizures can result from __________, __________, and other causes.
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Which autoimmune condition is associated with seizures?
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Which laboratory test is indicated for evaluating elevated levels due to muscle damage associated with severe seizures?
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Elevated prolactin levels can indicate seizures rather than psychogenic non-epileptic events.
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What might be assessed to evaluate thyroid function in seizure-related metabolic evaluations?
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Which of the following factors can lead to focal seizures?
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A review of medication lists is essential for identifying __________ related seizures.
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Match the laboratory test to its significance regarding seizures.
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Eclampsia is only associated with seizures during the postpartum period.
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Which of the following conditions is considered a neoplasia-related cause of seizures?
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What is the characteristic feature of non-motor seizures?
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The _______ phase is marked by recovery including symptoms like confusion and lethargy after a seizure.
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Eclamptic seizures are solely associated with high blood pressure in non-pregnant individuals.
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Match the following seizure types with their descriptions:
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List one laboratory test that may need to be performed for metabolic evaluation of seizures.
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In seizures related to genetic conditions, it is essential to consider __________ testing.
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Which neurotransmitter is associated with decreased cell excitability in seizures?
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Which additional test may be performed to evaluate pregnancy status in the context of eclamptic seizures?
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Focal seizures cannot generalize to affect both hemispheres.
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What is a common autonomic symptom experienced during focal seizures?
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Seizures are a result of abnormal, excessive synchronous electrical activity in the __________.
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Which type of seizure is characterized by a distal-to-proximal spread of movements?
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Study Notes
Seizures and Epilepsy Overview
- A seizure results from abnormal, excessive synchronous electrical activity in the central nervous system, manifesting in various clinical features such as focal or generalized seizures.
- Epilepsy is characterized by recurrent unprovoked seizures, defined as two or more seizures occurring greater than 24 hours apart, or one unprovoked seizure with at least a 60% recurrence risk.
Causes of Seizures: Mnemonic "Vitamin D and E"
-
Vascular Causes
- Commonly associated with focal seizures, include:
- Acute ischemic stroke
- Intracerebral hemorrhage
- Subarachnoid hemorrhage
- Hypertensive encephalopathy, seen as posterior reversible encephalopathy syndrome on MRI
- Severe anoxic brain injury due to low oxygen levels
- Commonly associated with focal seizures, include:
-
Infectious Causes
- Meningitis: Inflammation of meninges near the cortex
- Encephalitis: Inflammation of brain tissue
- Brain abscess: Loculated accumulation of pus or infection affecting the cortex
-
Traumatic Causes
- Epidural hematoma: Lens-shaped bleed due to rupture of middle meningeal artery
- Subdural hematoma: Crescent-shaped bleed, usually venous
-
Autoimmune Causes
- Antibody-mediated encephalitis, such as systemic lupus erythematosus
- Paraneoplastic syndromes linked to cancers (e.g., small cell lung cancer causing brain tissue antibody production)
-
Metabolic Causes
- Nutritional deficiencies affecting seizure triggers:
- Thiamine (B1) deficiency (Wernicke's encephalopathy)
- Hypoglycemia or, less commonly, hyperglycemia
- Hyponatremia and hypernatremia
- Hypocalcemia, hypomagnesemia, hypophosphatemia
- Uremia from kidney dysfunction or liver failure (ammonia buildup)
- Thyroid dysfunction (hyperthyroidism)
- Nutritional deficiencies affecting seizure triggers:
-
Idiopathic Causes
- Refers to epilepsy without identifiable triggers, including various epilepsy syndromes (e.g., West syndrome, Lennox-Gastaut syndrome).
-
Neoplastic Causes
- Focal seizures may arise from mass effect of tumors such as glioblastoma multiforme or meningiomas.
-
Drug-Related Causes
- Certain drugs lower seizure threshold; significant ones include:
- Opioids (e.g., maperidine, tramadol)
- Tricyclic antidepressants, anticholinergics, isoniazid, salicylate toxicity
- Stimulants (cocaine, amphetamines), metronidazole, penicillins, benzodiazepine withdrawal
- Alcohol withdrawal and lithium toxicity
- Certain drugs lower seizure threshold; significant ones include:
-
Eclampsia
- Associated with pregnant individuals experiencing high blood pressure and seizures.
Pathophysiology of Seizures
- Seizures arise from:
- Decreased inhibitory (GABAergic) neurotransmission.
- Increased excitatory (glutamatergic) neurotransmission.
- Glutamate binding to NMDA and AMPA receptors causes increased cation (Na+, Ca2+) influx, leading to depolarization and action potential generation.
- Dysfunction in GABA-A receptors reduces chloride ion influx, decreasing the cells' inhibitory potential and promoting excitability.
Clinical Features
-
Focal Seizures
- Occur at a specific point in one hemisphere of the brain, can remain localized or spread.
-
Generalized Seizures
- Involve simultaneous activity across both cerebral hemispheres, affecting overall brain function.### Focal Seizures
-
Occur in a specific location in one cerebral hemisphere with synchronous excessive electrical activity.
-
Can result in abnormal motor, sensory, autonomic, and psychological symptoms depending on the affected brain area.
Frontal Lobe Involvement
- Controls motor activity through areas like primary motor cortex, supplementary motor cortex, and Broca's area.
- Abnormal activity in the right frontal lobe may lead to contralateral abnormal movements.
Sensory Symptoms
- Abnormal electrical activity can also affect sensory areas:
- Parietal Lobe: abnormal sensations (pain, paresthesia) on the contralateral side.
- Occipital Lobe: visual sensations, including hallucinations.
- Temporal Lobe: auditory sensations (e.g., hearing non-existent sounds) and olfactory sensations (e.g., intense smells like burnt toast).
Autonomic and Psychological Symptoms
- Involves deep temporal lobes and insula, leading to:
- Tachycardia (increased heart rate), hypertension, urinary incontinence, salivation, and sweating.
- Emotional symptoms such as anger or hypersexual behavior, and psychological symptoms like déjà vu or depersonalization.
Seizure Phases
- Aura: Pre-seizure sensation that may include déjà vu, impending sense of doom, nausea, and automatisms (e.g., lip smacking, rapid eye blinking).
- Ictal Event: Visible seizure activity, classified as focal or generalized.
- Post-Ictal Phase: Recovery phase characterized by confusion, lethargy, amnesia, and possibly Todd's paralysis (weakness on one side of the body).
Types of Focal Seizures
-
Focal Seizures with Impairment:
- Involves the thalamus and reticular formation, leading to loss of consciousness.
- Characterized by auras, automatisms, and post-ictal symptoms.
-
Focal Seizures without Impairment:
- No thalamic or reticular formation involvement, no loss of consciousness, auras, or post-ictal state.
Jacksonian March
- A type of motor seizure characterized by a distal-to-proximal spread of movements (e.g., shaking starting in fingers and moving up the arm).
Generalization of Focal Seizures
- Focal seizures can secondarily generalize by spreading through the corpus callosum to both hemispheres, leading to generalized seizures like tonic-clonic seizures.
- Notable signs of secondary generalization may include aura, automatisms, unilateral shaking, and Todd's paralysis during the post-ictal state.
Generalized Seizures
- Involve bilateral hemispheric involvement from the onset, distinguishing them from focal seizures that secondarily generalize.### Generalized Seizures
- Involve bilateral hemispheric activity with thalamic and reticular formation impairment.
- Cause loss of consciousness and a postictal state, especially in generalized motor seizures.
- Two main types:
- Generalized Motor Seizures
- Non-Motor Seizures (Absence Seizures).
Generalized Motor Seizures
- Types include:
- Tonic
- Clonic
- Tonic-Clonic (Grand Mal)
- Atonic
- Myoclonic.
- Classic presentation includes convulsions with muscle contractions, affecting upper and lower limbs, trunk, and respiratory muscles.
- Can lead to:
- Involuntary screaming or crying due to respiratory muscle contraction.
- Upward eye movement (up gaze or eye rolling).
- Pooling of oral secretions due to muscle clenching.
- Tongue biting from jaw muscle contraction.
- Incontinence (urinary and fecal) from sphincter muscle involvement.
- Autonomic effects such as tachycardia and hypertension.
- Postictal state characterized by confusion, lethargy, and amnesia lasting until baseline recovery.
Non-Motor Seizures (Absence Seizures)
- Also known as "petit mal" seizures.
- Characterized by brief staring episodes or daydreaming, with no loss of muscle tone.
- Can occur up to 100 times daily.
- May include automatisms like rapid blinking or lip-smacking.
- Lack a postictal state.
- EEG shows a characteristic 3 Hz spike and wave pattern.
Evaluation and Diagnosis of Seizures
- History and clinical features determine whether seizures are focal or generalized.
- Definition of epilepsy: two unprovoked seizures >24 hours apart or one unprovoked seizure with a 60% recurrence risk.
- Assessment of anti-epileptic drug (AED) levels to evaluate treatment adequacy:
- If low, increase dose of AED.
- If normal but below maximum, consider dose increase or switch AED.
- Evaluate for underlying causes in first-time seizures.
Causes of First-Episode Seizures
- Vascular: Stroke, hemorrhage, anoxic brain injury. Imaging (CT/MRI) essential for diagnosis.
- Infectious: Meningitis, encephalitis, brain abscess. Requires imaging, lumbar puncture, and blood cultures.
- Traumatic: Identify structural injuries via CT.
- Autoimmune: Evaluate history and profiles; consider specific antibody testing for encephalitis.
- Metabolic: Assess thyroid function, glucose, electrolyte levels (BMP or CMP with magnesium/phosphate).
- Neoplasia: Utilize CT and MRI with contrast for malignancy detection.
- Drug-related: Review medication lists and perform toxicology screening.
- Genetic: Consider genetic testing for hereditary seizure disorders.
Additional Laboratory Tests
- CK (Creatinine Kinase): Elevated in rhabdomyolysis due to prolonged seizures.
- Lactate levels: Potentially elevated due to lactic acidosis from metabolic demand during seizures.
- Prolactin levels: Elevated levels may indicate seizures rather than psychogenic non-epileptic events.
- Troponin levels: May indicate muscle damage associated with severe seizures.
Management of Eclamptic Seizures
- Associated with high blood pressure in pregnant individuals; may need urine/beta-hCG testing for pregnancy status.
Seizures and Epilepsy Overview
- Seizures arise from abnormal electrical activity in the central nervous system, presenting as focal or generalized seizures.
- Epilepsy is defined as recurrent unprovoked seizures: two or more occurring more than 24 hours apart, or one unprovoked seizure with at least a 60% risk of recurrence.
Causes of Seizures: Mnemonic "Vitamin D and E"
-
Vascular Causes:
- Associated with focal seizures.
- Include acute ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and hypertensive encephalopathy.
-
Infectious Causes:
- Meningitis and encephalitis cause inflammation around or within the brain.
- Brain abscess results from loculated infections affecting the cortex.
-
Traumatic Causes:
- Epidural hematoma occurs from middle meningeal artery rupture, leading to a lens-shaped bleed.
- Subdural hematoma, typically venous, presents as crescent-shaped bleeding.
-
Autoimmune Causes:
- Antibody-mediated conditions like systemic lupus erythematosus.
- Paraneoplastic syndromes may occur in cancers such as small cell lung cancer.
-
Metabolic Causes:
- Nutritional deficiencies, including thiamine (B1) leading to Wernicke's encephalopathy, and imbalances in glucose, sodium, calcium, magnesium, and phosphate can trigger seizures.
-
Idiopathic Causes:
- Epilepsy without identifiable triggers, encompassing syndromes like West syndrome and Lennox-Gastaut syndrome.
-
Neoplastic Causes:
- Tumors, such as glioblastoma multiforme, can cause focal seizures due to mass effects.
-
Drug-Related Causes:
- Certain drugs lower the seizure threshold; significant examples are opioids, tricyclic antidepressants, and alcohol withdrawal.
-
Eclampsia:
- High blood pressure and seizures in pregnant individuals.
Pathophysiology of Seizures
- Seizures result from decreased GABAergic and increased glutamatergic transmission.
- Glutamate binding to NMDA and AMPA receptors enhances Na+ and Ca2+ influx, promoting depolarization.
- Dysfunction in GABA-A receptors reduces chloride influx, leading to hyperexcitability.
Clinical Features
-
Focal Seizures:
- Originates from a local area in one hemisphere, symptoms vary based on the location.
-
Generalized Seizures:
- Involves synchronous activity across both hemispheres, affecting overall brain function.
Focal Seizures
- May present as abnormal motor, sensory, autonomic, and psychological symptoms, specific to the affected brain area.
Frontal Lobe Involvement
- Primary motor cortex manages motor activity; abnormal activity can cause contralateral movements.
Sensory Symptoms
- Parietal Lobe: Pain or paresthesia on opposite side.
- Occipital Lobe: Visual disturbances or hallucinations.
- Temporal Lobe: Auditory and olfactory sensations, like non-existent sounds or unusual smells.
Autonomic and Psychological Symptoms
- Deep temporal lobe involvement can produce symptoms such as tachycardia, urinary incontinence, and emotional changes.
Seizure Phases
- Aura: Pre-seizure sensations including nausea and déjà vu.
- Ictal Event: Observable seizure activity.
- Post-Ictal Phase: Recovery characterized by confusion and lethargy.
Types of Focal Seizures
- With Impairment: Loss of consciousness and characteristic post-seizure symptoms.
- Without Impairment: Consciousness remains intact.
Jacksonian March
- Motor seizures characterized by movements starting distally and progressing proximally.
Generalization of Focal Seizures
- Focal seizures can spread to become generalized, leading to more widespread symptoms and impacts.
Generalized Seizures
- Involve bilateral hemispheric activity from onset, causing loss of consciousness.
Generalized Motor Seizures
- Includes tonic, clonic, tonic-clonic, atonic, and myoclonic types, presenting with muscle contractions and various autonomic symptoms.
Non-Motor Seizures (Absence Seizures)
- Known as "petit mal," these feature brief staring episodes without loss of muscle tone, and can occur multiple times throughout the day.
Evaluation and Diagnosis of Seizures
- Diagnosis involves assessing clinical history and seizure classification.
- Evaluation for AED levels helps in managing treatment effectiveness and adjusting dosages.
- Identification of underlying causes is crucial, especially for first-time seizures.
Causes of First-Episode Seizures
- Evaluation focuses on vascular issues (e.g., stroke), infectious diseases (meningitis), traumatic injuries, autoimmune conditions, metabolic imbalances, tumors, and drug interactions.
Additional Laboratory Tests
- Elevated CK in rhabdomyolysis indicates prolonged seizures.
- Lactate and prolactin levels may provide further insights into seizure events.
Management of Eclamptic Seizures
- Eclamptic seizures in pregnant individuals require monitoring and may necessitate pregnancy status evaluation through urine/beta-hCG testing.
Seizures and Epilepsy Overview
- Seizures arise from abnormal electrical activity in the central nervous system, presenting as focal or generalized seizures.
- Epilepsy is defined as recurrent unprovoked seizures: two or more occurring more than 24 hours apart, or one unprovoked seizure with at least a 60% risk of recurrence.
Causes of Seizures: Mnemonic "Vitamin D and E"
-
Vascular Causes:
- Associated with focal seizures.
- Include acute ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and hypertensive encephalopathy.
-
Infectious Causes:
- Meningitis and encephalitis cause inflammation around or within the brain.
- Brain abscess results from loculated infections affecting the cortex.
-
Traumatic Causes:
- Epidural hematoma occurs from middle meningeal artery rupture, leading to a lens-shaped bleed.
- Subdural hematoma, typically venous, presents as crescent-shaped bleeding.
-
Autoimmune Causes:
- Antibody-mediated conditions like systemic lupus erythematosus.
- Paraneoplastic syndromes may occur in cancers such as small cell lung cancer.
-
Metabolic Causes:
- Nutritional deficiencies, including thiamine (B1) leading to Wernicke's encephalopathy, and imbalances in glucose, sodium, calcium, magnesium, and phosphate can trigger seizures.
-
Idiopathic Causes:
- Epilepsy without identifiable triggers, encompassing syndromes like West syndrome and Lennox-Gastaut syndrome.
-
Neoplastic Causes:
- Tumors, such as glioblastoma multiforme, can cause focal seizures due to mass effects.
-
Drug-Related Causes:
- Certain drugs lower the seizure threshold; significant examples are opioids, tricyclic antidepressants, and alcohol withdrawal.
-
Eclampsia:
- High blood pressure and seizures in pregnant individuals.
Pathophysiology of Seizures
- Seizures result from decreased GABAergic and increased glutamatergic transmission.
- Glutamate binding to NMDA and AMPA receptors enhances Na+ and Ca2+ influx, promoting depolarization.
- Dysfunction in GABA-A receptors reduces chloride influx, leading to hyperexcitability.
Clinical Features
-
Focal Seizures:
- Originates from a local area in one hemisphere, symptoms vary based on the location.
-
Generalized Seizures:
- Involves synchronous activity across both hemispheres, affecting overall brain function.
Focal Seizures
- May present as abnormal motor, sensory, autonomic, and psychological symptoms, specific to the affected brain area.
Frontal Lobe Involvement
- Primary motor cortex manages motor activity; abnormal activity can cause contralateral movements.
Sensory Symptoms
- Parietal Lobe: Pain or paresthesia on opposite side.
- Occipital Lobe: Visual disturbances or hallucinations.
- Temporal Lobe: Auditory and olfactory sensations, like non-existent sounds or unusual smells.
Autonomic and Psychological Symptoms
- Deep temporal lobe involvement can produce symptoms such as tachycardia, urinary incontinence, and emotional changes.
Seizure Phases
- Aura: Pre-seizure sensations including nausea and déjà vu.
- Ictal Event: Observable seizure activity.
- Post-Ictal Phase: Recovery characterized by confusion and lethargy.
Types of Focal Seizures
- With Impairment: Loss of consciousness and characteristic post-seizure symptoms.
- Without Impairment: Consciousness remains intact.
Jacksonian March
- Motor seizures characterized by movements starting distally and progressing proximally.
Generalization of Focal Seizures
- Focal seizures can spread to become generalized, leading to more widespread symptoms and impacts.
Generalized Seizures
- Involve bilateral hemispheric activity from onset, causing loss of consciousness.
Generalized Motor Seizures
- Includes tonic, clonic, tonic-clonic, atonic, and myoclonic types, presenting with muscle contractions and various autonomic symptoms.
Non-Motor Seizures (Absence Seizures)
- Known as "petit mal," these feature brief staring episodes without loss of muscle tone, and can occur multiple times throughout the day.
Evaluation and Diagnosis of Seizures
- Diagnosis involves assessing clinical history and seizure classification.
- Evaluation for AED levels helps in managing treatment effectiveness and adjusting dosages.
- Identification of underlying causes is crucial, especially for first-time seizures.
Causes of First-Episode Seizures
- Evaluation focuses on vascular issues (e.g., stroke), infectious diseases (meningitis), traumatic injuries, autoimmune conditions, metabolic imbalances, tumors, and drug interactions.
Additional Laboratory Tests
- Elevated CK in rhabdomyolysis indicates prolonged seizures.
- Lactate and prolactin levels may provide further insights into seizure events.
Management of Eclamptic Seizures
- Eclamptic seizures in pregnant individuals require monitoring and may necessitate pregnancy status evaluation through urine/beta-hCG testing.
Seizures and Epilepsy Overview
- Seizures arise from abnormal electrical activity in the central nervous system, presenting as focal or generalized seizures.
- Epilepsy is defined as recurrent unprovoked seizures: two or more occurring more than 24 hours apart, or one unprovoked seizure with at least a 60% risk of recurrence.
Causes of Seizures: Mnemonic "Vitamin D and E"
-
Vascular Causes:
- Associated with focal seizures.
- Include acute ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and hypertensive encephalopathy.
-
Infectious Causes:
- Meningitis and encephalitis cause inflammation around or within the brain.
- Brain abscess results from loculated infections affecting the cortex.
-
Traumatic Causes:
- Epidural hematoma occurs from middle meningeal artery rupture, leading to a lens-shaped bleed.
- Subdural hematoma, typically venous, presents as crescent-shaped bleeding.
-
Autoimmune Causes:
- Antibody-mediated conditions like systemic lupus erythematosus.
- Paraneoplastic syndromes may occur in cancers such as small cell lung cancer.
-
Metabolic Causes:
- Nutritional deficiencies, including thiamine (B1) leading to Wernicke's encephalopathy, and imbalances in glucose, sodium, calcium, magnesium, and phosphate can trigger seizures.
-
Idiopathic Causes:
- Epilepsy without identifiable triggers, encompassing syndromes like West syndrome and Lennox-Gastaut syndrome.
-
Neoplastic Causes:
- Tumors, such as glioblastoma multiforme, can cause focal seizures due to mass effects.
-
Drug-Related Causes:
- Certain drugs lower the seizure threshold; significant examples are opioids, tricyclic antidepressants, and alcohol withdrawal.
-
Eclampsia:
- High blood pressure and seizures in pregnant individuals.
Pathophysiology of Seizures
- Seizures result from decreased GABAergic and increased glutamatergic transmission.
- Glutamate binding to NMDA and AMPA receptors enhances Na+ and Ca2+ influx, promoting depolarization.
- Dysfunction in GABA-A receptors reduces chloride influx, leading to hyperexcitability.
Clinical Features
-
Focal Seizures:
- Originates from a local area in one hemisphere, symptoms vary based on the location.
-
Generalized Seizures:
- Involves synchronous activity across both hemispheres, affecting overall brain function.
Focal Seizures
- May present as abnormal motor, sensory, autonomic, and psychological symptoms, specific to the affected brain area.
Frontal Lobe Involvement
- Primary motor cortex manages motor activity; abnormal activity can cause contralateral movements.
Sensory Symptoms
- Parietal Lobe: Pain or paresthesia on opposite side.
- Occipital Lobe: Visual disturbances or hallucinations.
- Temporal Lobe: Auditory and olfactory sensations, like non-existent sounds or unusual smells.
Autonomic and Psychological Symptoms
- Deep temporal lobe involvement can produce symptoms such as tachycardia, urinary incontinence, and emotional changes.
Seizure Phases
- Aura: Pre-seizure sensations including nausea and déjà vu.
- Ictal Event: Observable seizure activity.
- Post-Ictal Phase: Recovery characterized by confusion and lethargy.
Types of Focal Seizures
- With Impairment: Loss of consciousness and characteristic post-seizure symptoms.
- Without Impairment: Consciousness remains intact.
Jacksonian March
- Motor seizures characterized by movements starting distally and progressing proximally.
Generalization of Focal Seizures
- Focal seizures can spread to become generalized, leading to more widespread symptoms and impacts.
Generalized Seizures
- Involve bilateral hemispheric activity from onset, causing loss of consciousness.
Generalized Motor Seizures
- Includes tonic, clonic, tonic-clonic, atonic, and myoclonic types, presenting with muscle contractions and various autonomic symptoms.
Non-Motor Seizures (Absence Seizures)
- Known as "petit mal," these feature brief staring episodes without loss of muscle tone, and can occur multiple times throughout the day.
Evaluation and Diagnosis of Seizures
- Diagnosis involves assessing clinical history and seizure classification.
- Evaluation for AED levels helps in managing treatment effectiveness and adjusting dosages.
- Identification of underlying causes is crucial, especially for first-time seizures.
Causes of First-Episode Seizures
- Evaluation focuses on vascular issues (e.g., stroke), infectious diseases (meningitis), traumatic injuries, autoimmune conditions, metabolic imbalances, tumors, and drug interactions.
Additional Laboratory Tests
- Elevated CK in rhabdomyolysis indicates prolonged seizures.
- Lactate and prolactin levels may provide further insights into seizure events.
Management of Eclamptic Seizures
- Eclamptic seizures in pregnant individuals require monitoring and may necessitate pregnancy status evaluation through urine/beta-hCG testing.
Seizures and Epilepsy Overview
- Seizures arise from abnormal electrical activity in the central nervous system, presenting as focal or generalized seizures.
- Epilepsy is defined as recurrent unprovoked seizures: two or more occurring more than 24 hours apart, or one unprovoked seizure with at least a 60% risk of recurrence.
Causes of Seizures: Mnemonic "Vitamin D and E"
-
Vascular Causes:
- Associated with focal seizures.
- Include acute ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and hypertensive encephalopathy.
-
Infectious Causes:
- Meningitis and encephalitis cause inflammation around or within the brain.
- Brain abscess results from loculated infections affecting the cortex.
-
Traumatic Causes:
- Epidural hematoma occurs from middle meningeal artery rupture, leading to a lens-shaped bleed.
- Subdural hematoma, typically venous, presents as crescent-shaped bleeding.
-
Autoimmune Causes:
- Antibody-mediated conditions like systemic lupus erythematosus.
- Paraneoplastic syndromes may occur in cancers such as small cell lung cancer.
-
Metabolic Causes:
- Nutritional deficiencies, including thiamine (B1) leading to Wernicke's encephalopathy, and imbalances in glucose, sodium, calcium, magnesium, and phosphate can trigger seizures.
-
Idiopathic Causes:
- Epilepsy without identifiable triggers, encompassing syndromes like West syndrome and Lennox-Gastaut syndrome.
-
Neoplastic Causes:
- Tumors, such as glioblastoma multiforme, can cause focal seizures due to mass effects.
-
Drug-Related Causes:
- Certain drugs lower the seizure threshold; significant examples are opioids, tricyclic antidepressants, and alcohol withdrawal.
-
Eclampsia:
- High blood pressure and seizures in pregnant individuals.
Pathophysiology of Seizures
- Seizures result from decreased GABAergic and increased glutamatergic transmission.
- Glutamate binding to NMDA and AMPA receptors enhances Na+ and Ca2+ influx, promoting depolarization.
- Dysfunction in GABA-A receptors reduces chloride influx, leading to hyperexcitability.
Clinical Features
-
Focal Seizures:
- Originates from a local area in one hemisphere, symptoms vary based on the location.
-
Generalized Seizures:
- Involves synchronous activity across both hemispheres, affecting overall brain function.
Focal Seizures
- May present as abnormal motor, sensory, autonomic, and psychological symptoms, specific to the affected brain area.
Frontal Lobe Involvement
- Primary motor cortex manages motor activity; abnormal activity can cause contralateral movements.
Sensory Symptoms
- Parietal Lobe: Pain or paresthesia on opposite side.
- Occipital Lobe: Visual disturbances or hallucinations.
- Temporal Lobe: Auditory and olfactory sensations, like non-existent sounds or unusual smells.
Autonomic and Psychological Symptoms
- Deep temporal lobe involvement can produce symptoms such as tachycardia, urinary incontinence, and emotional changes.
Seizure Phases
- Aura: Pre-seizure sensations including nausea and déjà vu.
- Ictal Event: Observable seizure activity.
- Post-Ictal Phase: Recovery characterized by confusion and lethargy.
Types of Focal Seizures
- With Impairment: Loss of consciousness and characteristic post-seizure symptoms.
- Without Impairment: Consciousness remains intact.
Jacksonian March
- Motor seizures characterized by movements starting distally and progressing proximally.
Generalization of Focal Seizures
- Focal seizures can spread to become generalized, leading to more widespread symptoms and impacts.
Generalized Seizures
- Involve bilateral hemispheric activity from onset, causing loss of consciousness.
Generalized Motor Seizures
- Includes tonic, clonic, tonic-clonic, atonic, and myoclonic types, presenting with muscle contractions and various autonomic symptoms.
Non-Motor Seizures (Absence Seizures)
- Known as "petit mal," these feature brief staring episodes without loss of muscle tone, and can occur multiple times throughout the day.
Evaluation and Diagnosis of Seizures
- Diagnosis involves assessing clinical history and seizure classification.
- Evaluation for AED levels helps in managing treatment effectiveness and adjusting dosages.
- Identification of underlying causes is crucial, especially for first-time seizures.
Causes of First-Episode Seizures
- Evaluation focuses on vascular issues (e.g., stroke), infectious diseases (meningitis), traumatic injuries, autoimmune conditions, metabolic imbalances, tumors, and drug interactions.
Additional Laboratory Tests
- Elevated CK in rhabdomyolysis indicates prolonged seizures.
- Lactate and prolactin levels may provide further insights into seizure events.
Management of Eclamptic Seizures
- Eclamptic seizures in pregnant individuals require monitoring and may necessitate pregnancy status evaluation through urine/beta-hCG testing.
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Description
This quiz provides an overview of seizures and epilepsy, exploring their definitions, clinical features, and causes. Learn about the distinctions between focal and generalized seizures, as well as the various vascular and infectious causes linked to seizure activity. Test your knowledge on this vital neurological topic.