Focal seizure; Jacksonian seizure; Seizure - partial (focal)
A partial seizure is an episode of abnormal electrical activity in one specific part of the brain.
See also:
All seizures are caused by abnormal electrical disturbances in the brain. Partial (focal) seizures occur when this electrical activity remains in a limited area of the brain. The seizures may sometimes turn into generalized seizures, which affect the whole brain. This is called secondary generalization.
Partial seizures can be further characterized as:
The abnormal electrical activity is due to an area of abnormal brain tissue. The abnormal tissue may have been present since birth or earlier (congenital), or may develop after a head injury, infection, stroke, or certain other conditions. In many patients, no obvious cause can be determined.
A partial seizure may occur at any age, as a single episode or as a repeated, chronic seizure disorder (epilepsy). They are seen less frequently in children than in adults.
Risk factors include any injury to the brain. This includes trauma, stroke, brain tumors, infections (such as meningitis), or prior brain surgery. A family history of these types of seizures may also increase your risk.
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