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Seizures l: Introduction

Seizures l: Introduction

Understanding seizures and epilepsy relies on key definitions that help in recognizing, classifying, and managing these disorders. These definitions provide a framework for recognizing, classifying, and managing seizure disorders.DefinitionsA seizure is a sudden, abnormal burst of electrical activity in the brain that can cause changes in awareness, movement, sensation, or behavior, depending on the area involved. Epilepsy is a chronic condition characterized by recurrent, unprovoked seizures,...

Seizures ll: Types

Seizures ll: Types

Seizures are sudden bursts of abnormal electrical discharge in the brain that interfere with normal function. They are commonly divided into three groups: focal seizures, generalized seizures, and other types that do not fit neatly into either category.Focal SeizuresFocal seizures begin in a single brain region. When awareness is preserved, they are called focal aware seizures and may cause sensations such as tingling, unusual smells, or flashing lights. When awareness is impaired, they are...

Seizures: Classification

Seizures: Classification

Epilepsy is primarily characterized by unpredictable seizures, either provoked by an identifiable factor, such as injury or illness, or unprovoked, occurring spontaneously without apparent cause.
Seizures are typically classified into two main categories: focal and generalized seizures.
Focal Seizures
Focal seizures originate from specific regions of the brain. These seizures are further sub-classified into two types:

Epilepsy ll: Types

Epilepsy ll: Types

Recurrent seizures, stemming from abnormal electrical activity in the brain, are the defining characteristic of epilepsy, a chronic neurological condition. Because seizure features vary greatly, epilepsy is classified using two systems: by seizure type and by epilepsy syndromes. These classifications enable clinicians to describe seizure patterns and select suitable treatment strategies.I. Classification by Seizure Type1. Focal EpilepsyFocal epilepsy begins in one hemisphere of the brain.

Epilepsy and Seizures: Overview

Epilepsy and Seizures: Overview

Epilepsy is a chronic neurological disease marked by recurrent, unpredictable seizures. These seizures are caused by abnormal electrical discharges in the brain, leading to behavior, sensation, or consciousness alterations. They can also cause transient impairment of awareness, interfering with daily activities.
Various factors can trigger epilepsy, including genetic factors, brain damage, metabolic causes, and unknown etiology. Diagnosis of epilepsy involves electroencephalography (EEG), which...

Antiepileptic Drugs: GABAergic Pathway Potentiators

Antiepileptic Drugs: GABAergic Pathway Potentiators

γ-aminobutyric acid or GABA, plays a pivotal role as an inhibitory neurotransmitter in the brain. GABA pathway potentiators, also known as GABAergic drugs, are a class of pharmaceutical agents designed to enhance the functioning of the GABAergic system. These medications primarily treat epilepsy, a neurological disorder characterized by recurrent seizures.
The key GABA pathway potentiators used in epilepsy management are as follows.
Benzodiazepines are a well-known class of drugs used for their...

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Electromagnetic Source Imaging in Presurgical Evaluation of Children with Drug-Resistant Epilepsy

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Generalized-onset seizures with secondary focal evolution.

Randy Williamson¹, Samrina Hanif, Gregory C Mathews

¹Department of Neurology, Vanderbilt University, Nashville, Tennessee, USA.

|March 6, 2009

Summary

Generalized-onset seizures can evolve to have focal features, challenging current classifications. Early diagnosis and appropriate treatment for absence or myoclonic seizures improve outcomes.

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Area of Science:

Neurology
Epilepsy Research

Background:

Current seizure classification expects generalized-onset seizures to remain generalized.
Partial-onset seizures may generalize secondarily, but the reverse is not typically anticipated.

Observation:

Six patients presented with generalized-onset seizures (absence or myoclonic) that evolved to exhibit focal discharge patterns.
Clinical presentation included behavioral arrest, automatisms, and postictal confusion.
EEG showed generalized spike-wave activity evolving to focal predominance, with generalized interictal activity and normal MRI.

Findings:

Four patients were initially misdiagnosed with complex partial seizures due to the evolving focal features.
All patients were refractory to initial treatments.
Three patients achieved seizure freedom, and three improved with antiepileptic drugs targeting generalized absence and myoclonic seizures.

Implications:

Generalized-onset seizures with acquired focal features represent a diagnostic challenge, often mistaken for complex partial seizures.
Recognizing this seizure evolution is crucial for accurate diagnosis and effective treatment.
Treatment with medications for generalized absence and myoclonic seizures shows a favorable response in these cases.