Seizure Disorder, Focal
BASICS
BASICS

BASICS
DESCRIPTION
DESCRIPTION
DESCRIPTION
- Seizures occur when abnormal synchronous neuronal discharges in the brain cause transient cortical dysfunction.
- Focal or localization-related seizures have previously been referred to as partial seizures and originate from a discrete focus limited to one cerebral hemisphere.
- Focal seizures are further divided into aware versus unaware and motor versus nonmotor:
- Focal seizures with impairment of awareness (formerly “complex partial seizures”)
- Focal seizures without impairment of awareness (formerly “simple partial seizures”)
EPIDEMIOLOGY
EPIDEMIOLOGY
EPIDEMIOLOGY
Prevalence
Prevalence
Prevalence
Focal seizures occur in 20/100,000 persons in the United States.
ETIOLOGY AND PATHOPHYSIOLOGY
ETIOLOGY AND PATHOPHYSIOLOGY
ETIOLOGY AND PATHOPHYSIOLOGY
- Focal seizures begin when a localized seizure focus produces an abnormal, synchronized depolarization within a neuronal network limited to one cerebral hemisphere; it may stay discretely localized or be widely distributed throughout that hemisphere.
- The area of cortex involved in the seizure determines the symptoms; for example, an epileptogenic focus in motor cortex produces contralateral motor symptoms.
- Most common etiologies vary by life stage:
- Early childhood: developmental/congenital malformation, trauma
- Young adults: developmental, infection, trauma
- Adults 40 to 60 years of age: cerebrovascular insult, infection, trauma
- Adults >60 years of age: cerebrovascular insult, trauma, neoplasm
Genetics
Genetics
Genetics
Benign rolandic epilepsy has an autosomal dominant inheritance pattern.
RISK FACTORS
RISK FACTORS
RISK FACTORS
- History of traumatic brain injury (TBI)
- Thiamine-deficient formula
COMMONLY ASSOCIATED CONDITIONS
COMMONLY ASSOCIATED CONDITIONS
COMMONLY ASSOCIATED CONDITIONS
Depression
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