Epilepsia

Chapter

67

III

Epilepsies
Bassel W. Abou-Khalil, Martin J. Gallagher, Robert L. Macdonald CHAPTER OUTLINE
Seizures and Epilepsy Definitions Ictal Phenomenology 1584 Classification of Seizures
Other Seizure Terminology 1586

1583

Glossary of Seizure Terminology and Other Definitions 1584

Migraine 1609 Sleep Disorders 1610 Paroxysmal Movement Disorders 1610

1585

Evaluationand Diagnosis

1610

Seizure Types

1586

Partial Seizures 1586 Generalized Seizures 1589

Evaluation of Recent-Onset Seizures and Epilepsy 1610 Evaluation of Drug-Resistant Seizures and Epilepsy 1612 Evaluation of Patients for Epilepsy Surgery 1613

Medical Therapy

1617

Classification of Epilepsies and Epileptic Syndromes 1591
Epileptic Syndromes 1591 Causes and Risk Factors1600

Causes of Acute Symptomatic Seizures 1602 Seizure Precipitants 1602 Epidemiology of Epilepsy and Seizures 1603
Descriptive Epidemiology 1603 Epidemiology of the First Unprovoked Seizure 1603

Initiating Therapy 1617 Antiepileptic Drug Considerations Based on Age and Gender 1622 Pharmacoresistance, Tolerance, and Seizure Aggravation 1622 Medication Adverse Effects 1623 Therapeutic DrugMonitoring 1623 Discontinuation of Antiepileptic Drug Therapy 1624

Surgical Therapy

1624

Morbidity and Mortality

1603 1605

Morbidity and Comorbidity 1603 Mortality in Epilepsy 1604

Timing 1624 Presurgical Evaluation 1625 Surgical Approaches 1625 Surgical Results and Predictors of Surgical Freedom 1626

Pathophysiology and Mechanisms
Epileptic Networks 1605 ElectrophysiologicalAbnormalities 1605 Histopathology 1606 Molecular Pathogenesis 1606

Other Therapies

1627

Dietary Therapy 1627 Vagus Nerve Stimulation 1628 Other Stimulation Therapies 1629 Radiosurgery 1629

Differential Diagnosis

1607

Psychogenic Nonepileptic Seizures 1608 Syncope 1609

Quality-of-Care Standards in the Management of Epilepsy 1629 Status Epilepticus 1630

Seizures and EpilepsyDefinitions
Seizures are transient events that include symptoms and/or signs of abnormal excessive hypersynchronous activity in the brain (Fisher et al., 2005). In 2005, the International League Against Epilepsy (ILAE) and International Bureau for Epilepsy (IBE) proposed a definition of epilepsy as a disorder of the brain characterized by an enduring predisposition to generate epileptic seizuresand by the neurobiological, cognitive, psychological, and social consequences of this condition (Fisher et al., 2005). Acute symptomatic seizures provoked by metabolic or toxic derangements or occurring acutely in the setting of head trauma or stroke do not define epilepsy. The traditional definition of epilepsy requires at least two unprovoked seizures. The definition proposed by the ILAE in 2005suggested that one epileptic seizure is sufficient to
© Copyright 2012 Elsevier Inc., Ltd., BV. All rights reserved. DOI: 10.1016/B978-1-4377-0434-1.00092-X

diagnose epilepsy if there is additional enduring alteration in the brain that increases the likelihood of future seizures, but the proposal did not specify what evidence is sufficient to define such an enduring alteration. The proposeddefinition has been controversial and has not been widely accepted (Beghi et al., 2010). The definition of epilepsy used in this chapter requires at least two unprovoked seizures, so a single unprovoked seizure is insufficient to define epilepsy. A variety of seizure types exist, and epilepsy is not a single entity but rather a collection of disorders that have in common the occurrence of seizures.Hence, a need exists for classification of seizures and of epilepsies and epileptic syndromes. The classification is important for communication and diagnostic purposes, but also for evaluating drug specificity and prescribing the most appropriate therapy. The diagnosis of certain seizure types can predict response to therapy and prognosis. 1583

1584 Part III—Neurological Diseases In 2001,...