Generalized onset clonic seizures

Henry Hasson MD

Epilepsy & Seizures

Updated 07.30.2024
Released 03.04.2013
Expires For CME 07.30.2027

Generalized onset clonic seizures

Author: Henry Hasson MD

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Editor: Solomon L Moshé MD

Generalized onset clonic seizures

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Introduction

Overview

Generalized onset clonic seizures are a relatively rare type of motor (convulsive) seizure mainly affecting infants and very young children. They also occur in patients with metabolic and electrolyte derangements. Clinically, they manifest with bilateral, rhythmic clonic convulsions, with each clonic event lasting fewer than 100 ms at a repetitive rate of 1 to 3 Hz. Consciousness is usually lost or impaired. There is significant misperception in terminology and definition and particularly in their differentiation from myoclonus. In this article, the author details the clinical manifestations, pathophysiology, EEG, differential diagnosis, and management of patients with generalized onset clonic seizures.

Key points

	• Generalized onset clonic seizures are rare and mainly affect infants and very young children.
	• Generalized onset clonic seizures manifest with bilateral clonic convulsions, each lasting fewer than 100 ms at a repetition rate of 1 to 3 Hz.
	• The distinction between myoclonic seizures and clonic seizures is not clear. Classically, clonic seizures are rapid rhythmically recurrent events, whereas myoclonic seizures are single or irregularly recurrent events.
	• Mechanisms are different from those of the clonic phase of generalized tonic-clonic seizures.
	• There is a need for better characterization of generalized onset clonic seizures with video-EEG correlations.

Historical note and terminology

Generalized onset clonic seizures were mainly investigated by Henri Gastaut and his school in Marseilles (13).

Clonic seizures. Perhaps because they occur almost exclusively in early childhood, clonic generalized epileptic seizures are recognized even less frequently than tonic generalized epileptic seizures. They are encountered most often by family practitioners and pediatricians rather than specialists in neurology or epileptology. Clonic seizures occur more frequently than often recognized.

Clinical description. The attacks begin with loss of consciousness associated either with sudden hypotonia or, conversely, with a brief generalized tonic spasm, sometimes so abbreviated that it could be considered as massive bilateral myoclonus. Both will cause falling. The child then remains on the floor for 1 or more minutes and is seized by a series of bilateral myoclonus, usually generalized, although often asymmetrical and predominating on one side or in one limb. Subsequently, the variability of amplitude, frequency, and spatial distribution of these jerks from one moment to the next may become extraordinary. The most unlikely combinations are observed. Rapid low-amplitude twitching of facial muscles, for instance, may be associated with infrequent but very intense jerks of the upper limbs and with such rapid myoclonus of the lower limbs that virtual tetanic contraction results. Certain authors believe that in some attacks the entire body can jerk at such a high frequency that they could be described as “vibratory generalized epileptic seizures.” In our experience, the existence of such seizures is very doubtful, and they would have to be distinguished from the vibratory periods of the generalized tonic-clonic seizures and from certain rare tremors that may occur during epileptic automatisms.

In some children, particularly those aged 1 to 3 years, the myoclonus remains bilaterally synchronous and massive throughout the attack, rather than showing such complex and unstable patterns.

The autonomic changes are relatively important during prolonged seizures in which accumulated bronchial secretions may cause respiratory distress. Regaining of consciousness is rapid after brief seizures. Those of long duration, however, may be followed by a confusional or even comatose state with generalized muscular hypotonia and areflexia.

Other forms of clonic seizures, which are seen in older subjects, are more properly considered as absence status with marked myoclonus, often rhythmic, or prolonged myoclonic absences with the jerks repeated at 3/sec.

NREM sleep is frequently accompanied by bilaterally synchronous polyspike discharges sometimes associated with myoclonus and leading at times to a hypnic clonic generalized epileptic seizure. However, both discharges and seizures are absent from REM sleep (13).

The ILAE Commission of 1981 classified generalized onset clonic seizures amongst generalized seizures together with generalized tonic-clonic seizures (GTCS), tonic seizures, myoclonic seizures, and absence seizures and defined them as follows:

	• Clonic seizures: Generalized convulsive seizures occasionally lack a tonic component and are characterized by repetitive clonic jerks. As the frequency diminishes, the amplitude of the jerks does not. The postictal phase is usually short. Some generalized convulsive seizures commence with a clonic phase passing into a tonic phase leading to a “clonic-tonic-clonic” seizure.
	• Ictal EEG consists of “Fast activity” (10 Hz or more) and slow waves, with an occasional spike-and-wave pattern.
	• The EEG interictal expression is of “spike-and-wave or polyspike-and-wave discharges” (03).

Clonic seizures are defined as follows in the ILAE glossary:

• “Clonic: Myoclonus that is regularly repetitive, involves the same muscle groups, at a frequency of approximately 2 to 3 c/s, and is prolonged. Synonym: rhythmic myoclonus” (02).

The ILAE core group classified clonic seizures amongst self-limited epileptic seizures of generalized onset with tonic or clonic manifestations and explains:

Clonic seizures are fast rhythmic events (1 to 2 Hz), associated, or not, with impaired consciousness. Mechanisms are different from those of the clonic phase of GTCS. In the latter, the clonic phase represents the phasing in of seizure-suppressing mechanisms, whereas in clonic seizures, the repetitive discharges appear to be due primarily to rhythmic excitatory discharges. There may be several types of generalized clonic seizures…. The distinction between myoclonic seizures and clonic seizures is not clear. Classically, clonic seizures are rapid rhythmically recurrent events, whereas myoclonic seizures are single or irregularly recurrent events… Differential diagnosis between myoclonic and clonic seizures can be difficult because a single jerk can be a fragment of a clonic seizure (09).

In the 2014 ILAE “epilepsy diagnosis” manual, generalized onset clonic seizures are categorized among generalized convulsive seizures. Generalized seizures are convulsive, absence, tonic, atonic, and myoclonic (04).

“Generalized convulsive seizures are typically bilateral and symmetric although variants with asymmetry including head and eye deviation can be seen. A tonic-clonic seizure is a seizure consisting of a tonic and a clonic phase, typically in this order, however, variations such as clonic-tonic-clonic are also seen. A clonic seizure is a seizure involving bilaterally rhythmic jerking and may occur alone or in combination with tonic activity where there is bilaterally increased tone of the limbs typically lasting seconds to a minute. The jerking in a clonic seizure is more sustained and rhythmic than seen in a myoclonic seizure” (04).

The most recent ILAE positional papers on the operational classification of seizure types retain the name “generalized onset clonic seizures” and classify them amongst “generalized onset motor seizures” (12; 11). Generalized onset seizures are motor (tonic-clonic, clonic, tonic, myoclonic, myoclonic-tonic-clonic, myoclonic-atonic, atonic, epileptic spasms) or nonmotor (absence) typical, atypical, myoclonic, eyelid myoclonia. Also, the authors explain that “Generalized clonic seizures begin, progress, and end with sustained rhythmic jerking of limbs on both sides of the body and often head, neck, face, and trunk. Generalized clonic seizures are much less common than are tonic-clonic seizures, usually occur in infants, and should be distinguished from jitteriness or shuddering attacks” and “Myoclonus differs from clonus by being briefer and not regularly repetitive” (11).

	• Clonic: Jerking, either symmetric or asymmetric, which is regularly repetitive and involves the same muscle groups.
	• Myoclonic: Sudden, brief (< 100 msec), involuntary single or multiple contraction(s) of muscle(s) or muscle groups of variable topography (axial, proximal limb, distal). Myoclonus is less regularly repetitive and less sustained than clonus.

Dr. Panayiotopoulos’s clarifications. It is apparent that according to the various ILAE classifications and definitions, generalized onset clonic seizures are mainly distinguished from generalized myoclonic seizures by their rhythmicity.

Clonic and myoclonic seizures (EMG)

Illustrative presentation of EMG recording during various types of seizures, including clonic and myoclonic seizures. Note that the only difference between clonic and myoclonic seizures is that the former are rhythmic whereas the ...

This has created significant overlap in what to call clonic or myoclonic seizures, and often these terms are used interchangeably. An example of this is “myoclonic absence seizures,” which manifest with clonic rather than myoclonic motor manifestations.

Generalized onset clonic seizure

A brief generalized onset clonic seizure recorded in an infant. Spikes are prominent only at the start of the rhythmic delta wave activity that persisted for several more seconds with associated clonus. (Used with permission from:...
Myoclonic absence seizures of structural cause (video-EEG)

Video EEG recorded typical myoclonic absence seizures in a patient aged 15 months. Clinically, there were rhythmic and symmetrical violent myoclonic jerks, mainly of the arms, coinciding with the multiple spike components. Note th...

Conversely, what is called “clonic-tonic-clonic” generalized seizure of juvenile myoclonic epilepsy (05) may indeed be myoclonic-tonic-clonic seizure because the preceding events are random and irregular myoclonic seizures (22). This view has now been substantiated with the introduction of this term in the ILAE operational classification of seizure types: “Generalized myoclonic-tonic-clonic seizures begin with a few myoclonic jerks followed by tonic-clonic activity. These seizures are commonly seen in patients with juvenile myoclonic epilepsy and occasionally with other generalized epilepsies. It is arguable whether the initial jerks are myoclonic or clonic, but they are rarely sufficiently sustained to be considered clonic” (11).

Clinical manifestations

Presentation and course

Generalized onset clonic seizures, by definition, manifest with bilateral rhythmic clonic convulsions only. Their duration varies from minutes to hours, but each clonic event lasts fewer 100 ms at a rate of 1 to 3 Hz.

The generalized onset clonic seizures differ from (1) the clonic phase of generalized tonic-clonic seizures, which occur in continuity with the preceding tonic convulsions and (2) myoclonic seizures that are defined as singular or irregular recurrent events as opposed to the clonic seizures that are rhythmic at 1 to 5 Hz.

They also differ from other types of seizure that manifest with tonic components mixed with myoclonus (eg, eyelid myoclonia). However, repetitive clonic seizures are clearly manifested in the so-called “myoclonic absence seizures” in which the motor component is clonic rhythmic at 2.5 to 4.5 Hz, rather than myoclonic.

Generalized onset clonic seizure

A brief generalized onset clonic seizure recorded in an infant. Spikes are prominent only at the start of the rhythmic delta wave activity that persisted for several more seconds with associated clonus. (Used with permission from:...
Myoclonic absence seizures of structural cause (video-EEG)

Video EEG recorded typical myoclonic absence seizures in a patient aged 15 months. Clinically, there were rhythmic and symmetrical violent myoclonic jerks, mainly of the arms, coinciding with the multiple spike components. Note th...

Clonic seizures may cause repetitive rhythmic flexion and extension of the body or repetitive rhythmic contraction and relaxation of the affected muscles.

In neonates, infants, and very young children, generalized onset clonic seizures may appear as more or less rhythmically repeated, bilateral clonic contractions, distributed more or less regularly throughout the entire body and associated with loss of consciousness and autonomic symptoms and signs (13). However, in other reports generalized onset clonic seizures are brief and may occur without loss of consciousness; autonomic manifestations may not be apparent if they are brief and are associated with loss or impairment of consciousness. Reports of long generalized clonic seizures without video-EEG confirmation of their onset may have missed the initial tonic phase of a tonic-clonic seizure or the early dystonic elements of focal-onset clonic seizures. In pure generalized clonic seizures, there is neither an initial tonic phase nor a clonic-tonic-clonic sequence. Motor activity is bilateral and symmetric (21). However, generalized onset clonic seizures are also described as asymmetrical and can be unilateral (08; 10).

In one study with video-EEG documentation, only 6 of 101 distinct infantile seizures of 77 infants aged 1 month to 2 years were classified as generalized onset clonic seizures (15). These seizures were characterized by generalized clonic jerks (bilateral clonus). However, several of these were so brief that one might argue that the seizures were simply a combination of several repeated or erratic myoclonia (21).

Generalized clonic seizures and hemiclonic seizures are common in Dravet syndrome and are mandatory for diagnosis. These are often prolonged and frequently triggered by fever, elevated environmental temperature, or immunization (28).

Prognosis and complications

Prognosis of conditions associated with generalized onset clonic seizures depends on their underlying etiology (08; 21; 24).

Clinical vignette

Following is a case illustrated with ictal EEG recording by Gastaut and Broughton as a clonic generalized seizure, including significant comments by the authors regarding its differentiation from other types of seizures in childhood (13).

A 7-year-old boy presented epileptic seizures of long duration during each childhood febrile illness. The attacks consisted of complete loss of consciousness associated with recurrent myoclonus (generalized, focal, and fragmentary), superimposed on intense muscular hypotonia between the jerks. The seizure was, therefore, intermediate between the more usual clonic generalized seizures and the atonic generalized seizures. Such attacks have at times been described as "myoclonic-atonic seizures" (or crises amyotonique-cloniques).

The seizure was activated by artificially-induced fever. At 39.2° C (103.0° F) the child abruptly lost consciousness and became pale, the eyes were deviated upwards, muscle tone was completely lost, and focal and occasionally generalized myoclonus occurred. The EEG discharge is of abrupt onset and consists of a mixture of rhythmic slow activity, which, moreover, tends to decrease in frequency during the seizure, and a rhythm at 10 cps predominating in the frontal regions and of decreasing magnitude. The two activities produce together the appearance of spike and wave or polyspike and wave discharges of decreasing frequency. Almost 4 minutes of the seizure, which lasted 5 minutes in total, are shown.

The illustration could serve equally for both the clonic seizures and the atonic generalized epileptic seizures of childhood, which usually differ only in a slightly greater abundance of fast recruiting activity at 10 cps in the clonic seizures and of slow waves in the atonic (and akinetic) seizures. Prolonged absence status with myoclonus may at times be considered to represent another form of clonic generalized epileptic seizure (13).

Biological basis

Localization

Very little is known about the localization and pathophysiology of these seizures.

By definition, “generalized onset seizures are conceptualized as originating at some point within, and rapidly engaging, bilaterally distributed networks. Such bilateral networks can include cortical and subcortical structures but do not necessarily include the entire cortex. Although individual seizure onsets can appear localized, the location and lateralization are not consistent from one seizure to another. Generalized seizures can be asymmetric” (01).

According to the ILAE core group, the mechanisms of clonic seizures appear to be due primarily to rhythmic excitatory discharges whereas the clonic phase of GTCS represents the phasing in of seizure-suppressing mechanisms (09).

According to Gastaut:

The various features of clonic seizures may be explained by excessive neuronal discharge more or less limited to the thalamic formation in a person with highly efficient inhibitory mechanisms so that the excitatory and inhibitory systems are fairly well balanced. This would account for both the length of the attacks and the continuous interplay between EEG polyspikes (recruiting rhythm) and slow waves (inhibitory system), each predominating at different moments with only occasional and erratic discharge of motor systems (thalamo-reticularspinal and thalamo-corticospinal) giving rise to myoclonus (13).

Pathophysiology

In animals, Toth and associates found that insertional inactivation of the mouse jrk gene resulted in handling-induced whole-body jerks, generalized clonic seizures, and epileptic brain activity, a phenotype termed “jerky” (26). All homozygous animals displayed seizures. Homozygotes also displayed some degree of kyphosis of the thoracic spine and were proportionate dwarfs. Approximately half died before 3 months of age. Approximately 50% of the hemizygous animals showed generalized clonic seizures. The other hemizygous animals either displayed seizures limited to the head and limbs or showed no seizure activity. There was no apparent correlation between the level of jerky mRNA and the severity of seizures in hemizygote.

Differential diagnosis

Confusing conditions

Clonic versus myoclonic seizures. The main difficulty is in differentiating clonic seizures from myoclonic seizures and from seizures manifesting with clonic convulsions in continuity or together with tonic, absence, and myoclonic manifestations.

Generalized onset clonic seizure

A brief generalized onset clonic seizure recorded in an infant. Spikes are prominent only at the start of the rhythmic delta wave activity that persisted for several more seconds with associated clonus. (Used with permission from:...
Myoclonic absence seizures of structural cause (video-EEG)

Video EEG recorded typical myoclonic absence seizures in a patient aged 15 months. Clinically, there were rhythmic and symmetrical violent myoclonic jerks, mainly of the arms, coinciding with the multiple spike components. Note th...

In early childhood and epileptic encephalopathies, GTCS may appear only as generalized clonic convulsions, in which the preceding tonic phase is brief and inconspicuous.

Focal onset clonic seizures may present with bilateral clonic convulsions of the upper extremities without clouding of consciousness; however, in these cases, there are no EEG generalized spike-wave discharges, and the seizures originate in the supplementary motor area.

Nonepileptic attacks. Extremely sustained startle-induced clonus is a nonepileptic motor attack mimicking clonic seizures in children with encephalopathy (18). Clonus is a pathological motor pattern characterized by involuntary, rhythmic, and brisk muscular contractions in response to peripheral stimuli producing muscle stretching. It indicates pathological involvement of the corticospinal tract and can be considered as a functional spastic movement disorder of variable clinical presentation and duration. Severe and prolonged episodes of startle-induced clonic attacks associated with severe apnea may rarely occur in infants with severe encephalopathy. The clinical characteristics of such episodes are very similar to those of clonic epileptic seizures.

Generalized clonic seizures in infants should be distinguished from jitteriness or shuddering attacks (17).

Associated and underlying disorders

Generalized onset clonic seizures are not specific to any syndrome. They have been described mainly in infants and very young children with febrile seizures, acute symptomatic situations, and metabolic derangements such as hypoglycemia, hyponatremia, or hypocalcemia, pyridoxine dependency in infants, anoxic and toxic encephalopathies, progressive myoclonus epilepsies, Angelman syndrome and other chromosomal disorders, myoclonic-atonic epilepsy, and Dravet syndrome (25; 13; 20; 08; 21; 22; 10; 24). According to one report, generalized onset clonic seizures were the most common ictal event in patients with Panayiotopoulos syndrome and convulsive status epilepticus, and one third required admission to intensive care units (27). According to Panayiotopoulos, in all these reports, it is doubtful whether the so-called generalized onset clonic seizures are genuine generalized onset clonic seizures or, most likely, myoclonic or focal-onset clonic seizures.

Diagnostic workup

The ILAE Neurophysiology Task Force published a comprehensive two-part review on the role of EEG in the diagnosis and classification of the epilepsy syndrome, which can be a tool for clinical practice (16).

Interictal EEG. Interictal EEG can range from normal to grossly abnormal.

Ictal EEG. Each clonic convulsion corresponds to a generalized discharge of spike and multiple spikes or, more rarely, a mixture of rapid rhythms and slow waves (13; 04). Although individual seizure onsets can appear localized, the location and lateralization are not consistent from one seizure to another (04).

In one study with video-EEG documentation, the EEG ictal features of six infants consisted of runs of repetitive generalized sharp waves or spikes with occipital or frontal predominance (15). Because the seizures were rather diffuse, no spread was observed on evolution. Four (66%) stuttered (repeated epochs of ictal features mixed with epochs of usual background activity), and two (33%) had an abrupt termination (clear-cut instant change in EEG features from ictal activity to postictal features, such as attenuation, slowing, or return to the usual background activity). Clonus did not reliably correlate with the presence of spikes (15).

Myoclonic absence seizure in a child (EEG)

Video-EEG of a 15-month-old girl recorded typical myoclonic absence seizures. Clinically, there were rhythmic and symmetrical violent myoclonic jerks, mainly of the arms, coinciding with the multiple spike components. Note the reg...

Other tests. Brain imaging and other tests (eg, metabolic, electrolytes) may be needed to detect the underlying pathology.

Management

Management depends on the underlying etiology. Correction of the underlying etiology is sufficient for clonic seizures associated with electrolyte or metabolic derangements. Pure generalized onset clonic seizures require prophylactic treatment with antiepileptic drugs that are suitable for generalized seizures such as sodium valproate, lamotrigine, and levetiracetam. Rufinamide and clobazam have been approved for Lennox-Gastaut syndrome and may be effective for clonic seizures. Cenobamate and brivaracetam have been approved for focal seizures and although they have not specifically been tested for clonic seizures, they may be effective.

Ketogenic diet is indicated in severe infantile epileptic encephalopathies with clonic seizures (19). Also, there is a growing interest in the use of cannabidiol for the treatment of these severe epileptic encephalopathies like Dravet and Lennox-Gastaut syndrome. In a double-blind, placebo-controlled trial, in a 14-week treatment period of patients with Dravet syndrome, cannabidiol was significantly beneficial particularly in convulsive seizures, with 5% of patients becoming seizure-free though associated with higher rates of adverse events (06; 07). In June 2018, Epidiolex (cannabidiol oral formulation) from GW Pharmaceuticals obtained marketing authorization from the FDA for the treatment of Dravet and Lennox-Gastaut syndrome. More information can be accessed at: http://www.draccon.com/dravet-pipeline. The package insert for Epidiolex also provides information and can be reviewed at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/210365lbl.pdf.

Real-time automated detection of clonic seizures in newborns has been described based on a low-complexity image processing approach extracting the differential average luminance from videotaped body movements (23). This algorithm reliably detects neonatal clonic seizures and differentiates them from either noise, random movements, or other seizure types.

Outcomes

Prognosis of conditions associated with generalized onset clonic seizures depends on their underlying etiology (08; 21; 24).

Media

References

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02: Blume WT, Luders HO, Mizrahi E, Tassinari C, van Emde BW, Engel J Jr. Glossary of descriptive terminology for ictal semiology: report of the ILAE task force on classification and terminology. Epilepsia 2001;42:1212-8.** PMID 11580774
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05: Delgado-Escueta AV, Enrile-Bacsal F. Juvenile myoclonic epilepsy of Janz. Neurology 1984;34:285-94. PMID 6422321
06: Devinsky O, Cross JH, Wright S. Trial of cannabidiol for drug-resistant seizures in the Dravet syndrome. N Engl J Med 2017;377(7):699-700. PMID 28813226
07: Devinsky O, Nabbout R, Miller I, et al. Long-term cannabidiol treatment in patients with Dravet syndrome: an open-label extension trial. Epilepsia 2019;60(2):294-302. PMID 30582156
08: Dravet C, Seino M. Generalized clonic and hemiclonic seizures. In: Engel J Jr, Pedley TA, editors. Epilepsy: A Comprehensive Textbook. Second ed. Philadelphia: Lippincott William and Wilkins, 2008:563-71.
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10: Engel J Jr. Seizures and epilepsy. 2nd edition. Oxford: Oxford University Press, 2013:226-7.**
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12: Fisher RS, Cross JH, French JA, et al. Operational classification of seizure types by the International League Against Epilepsy: position paper of the ILAE Commission for Classification and Terminology. Epilepsia 2017a;58(4):522-30. PMID 28276060
13: Gastaut H, Broughton R. Epileptic seizures. Clinical and electrographic features, diagnosis and treatment. Springfield Illinois: Charles C Thomas, 1972.**
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Contributors

All contributors' financial relationships have been reviewed and mitigated to ensure that this and every other article is free from commercial bias.

Author

Henry Hasson MD

Dr. Hasson of Albert Einstein College of Medicine has no relevant financial relationships to disclose.
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Editor

Solomon L Moshé MD

Dr. Moshé of Albert Einstein College of Medicine has no relevant financial relationships to disclose.
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Former Authors

C P Panayiotopoulos MD PhD
Jerome Engel Jr MD PhD

Patient Profile

Age range of presentation: 0 month to 12 years
Sex preponderance: Female=Male
Heredity: Heredity may be a factor.
Population groups selectively affected: None

ICD & OMIM codes

ICD-9: Epilepsy and recurrent seizures: 345

Generalized convulsive epilepsy: 345.1

Epilepsy, unspecified: 345.9

Epilepsy: G40

Generalized idiopathic epilepsy and epileptic syndromes: G40.3

Other generalized epilepsy and epileptic syndromes: G40.4

Special epileptic syndromes: G40.5

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Generalized onset clonic seizures

Associated Disorders

Angelman syndrome and other chromosomal disorders
anoxic and toxic encephalopathies
Dravet syndrome
febrile seizures
metabolic disturbances
- myoclonic-atonic epilepsy
- progressive myoclonus epilepsies
- pyridoxine dependency in infants

Differential Diagnosis

myoclonic seizures
seizures manifesting with clonic convulsions in continuity or together with tonic, absence, and myoclonic manifestations
focal onset clonic seizures
jitteriness
shuddering attacks

Generalized onset clonic seizures

Generalized onset clonic seizures

Introduction

Overview

Key points

Historical note and terminology

Clinical manifestations

Presentation and course

Prognosis and complications

Clinical vignette

Biological basis

Localization

Pathophysiology

Epidemiology

Prevention

Differential diagnosis

Confusing conditions

Associated and underlying disorders

Diagnostic workup

Management

Outcomes

Media

References

Contributors

Author

Editor

Former Authors

Patient Profile

ICD & OMIM codes

This is an article preview.
Start a Free Account
to access the full version.

Questions or Comment?

Also in This Category

Photosensitive occipital lobe epilepsy

Intermittent explosive disorder

Pyridoxine/P5P-dependent developmental epileptic encephalopathy

Reflex seizures

Anti-LGI1 encephalitis

Self-limited (familial) neonatal epilepsy

Epilepsy with auditory features

Alcohol withdrawal seizures

Generalized onset clonic seizures

Introduction

Overview

Key points

Historical note and terminology

Clinical manifestations

Presentation and course

Prognosis and complications

Clinical vignette

Biological basis

Localization

Pathophysiology

Epidemiology

Prevention

Differential diagnosis

Confusing conditions

Associated and underlying disorders

Diagnostic workup

Management

Outcomes

Media

References

Contributors

Author

Editor

Former Authors

Patient Profile

ICD & OMIM codes

This is an article preview. Start a Free Account to access the full version.

Questions or Comment?

Also in This Category

Photosensitive occipital lobe epilepsy

Intermittent explosive disorder

Pyridoxine/P5P-dependent developmental epileptic encephalopathy

Reflex seizures

Anti-LGI1 encephalitis

Self-limited (familial) neonatal epilepsy

Epilepsy with auditory features

Alcohol withdrawal seizures

This is an article preview.
Start a Free Account
to access the full version.