Glossary

Terms in this glossary, e.g. seizure, ictus, which have widespread applicability in other fields of clinical neuroscience, are herein defined according to their references to epilepsy. The numbering system is such that words related are built upon a fundamental word such as "Aura" which has many descriptors for it including the sensory and abdominal type and so on. And if one has experiential type of aura, this can be either of the 4 other possible subtypes including illusory or hallucinatory.

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index

1.1 CRYPTOGENIC
1.2 SYMPTOMATIC
1.3 ICTAL PERIOD
1.4 INTERICTAL PERIOD

EPILEPSY

2.1 GRAND MAL

2.2 PETIT MAL

2.3 GENERALIZED EPILEPSY

2.3.1 ABSENCE EPILEPSY

2.3.2 TONIC-CLONIC EPILEPSY

2.3.3 INFANTILE SPASM

2.4 PARTIAL EPILEPSY

2.4.1 COMPLEX PARTIAL EPILEPSY

2.4.2 MOTOR PARTIAL EPILEPSY

2.4.3 SENSORY PARTIAL EPILEPSY

2.4.4 FRONTAL LOBE EPILEPSY

2.4.5 TEMPORAL LOBE EPILEPSY

2.4.6 ROLANDIC EPILEPSY

2.5 STATUS EPILEPTICUS

2.5.1 EPILEPSIA PARTIALIS CONTINUA

2.6 BENIGN NEONATAL EPILEPSY

2.7 POST TRAUMATIC EPILEPSY

2.8 REFLEX EPILEPSY

2.9 FEBRILE SEIZURES

2.10 LANDAU-KLEFFNER SYNDROME

3 CONVULSION

A childhood seizure disorder characterized by rhythmic electrical brain discharges of geneneralized onset. Clinical features include a sudden cessation of ongoing activity usually without loss of postural tone. Rhythmic blinking of the eyelids or lip smacking frequently accompanies the seizure. The usual duration is 5-10 seconds, and multiple episodes may occur daily. Juvenile absence epilepsy is characterized by the juvenile onset of absence seizures and an increased incidence of myoclonus and tonic-clonic seizures.

2.3.2 TONIC-CLONIC EPILEPSY

A generalized seizure disorder characterized by recurrent major motor seizures. The initial brief tonic phase is marked by trunk flexion followed by diffuse extension of the trunk and extremities. The clonic phase features rhythmic flexor contractions of the trunk and limbs, pupillary dilation, elevations of blood pressure and pulse, urinary incontinence, and tongue biting. This is followed by a profound state of depressed consciousness (post-ictal state) which gradually improves over minutes to hours. The disorder may be cryptogenic, familial, or symptomatic (caused by an identified disease process).

2.3.3 INFANTILE SPASMS

An epileptic syndrome characterized by the triad of infantile spasms, hypsarrhythmia, and arrest of psychomotor development at seizure onset. The majority present between 3-12 months of age, with spasms consisting of combinations of brief flexor or extensor movements of the head, trunk, and limbs. The condition is divided into two forms: cryptogenic (idiopathic) and symptomatic (secondary to a known disease process such as intrauterine infections; nervous system abnormalities; BRAIN DISEASES, METABOLIC, INBORN; prematurity; perinatal asphyxia; TUBEROUS SCLEROSIS; etc.)

2.4 PARTIAL EPILEPSY

Conditions characterized by recurrent paroxysmal neuronal discharges which arise from a focal region of the brain. Partial seizures are divided into simple and complex, depending on whether consciousness is unaltered (simple partial seizure) or disturbed (complex partial seizure). Both types may feature a wide variety of motor, sensory, and autonomic symptoms. Partial seizures may be classified by associated clinical features or anatomic location of the seizure focus. A secondary generalized seizure refers to a partial seizure that spreads to involve the brain diffusely.

2.4.1 COMPLEX PARTIAL EPILEPSY

A disorder characterized by recurrent partial seizures marked by impairment of cognition. During the seizure the individual may experience a wide variety of psychic phenomenon including formed hallucinations, illusions, deja vu, intense emotional feelings, confusion, and spatial disorientation. Focal motor activity, sensory alterations and AUTOMATISM may also occur. Complex partial seizures often originate from foci in one or both temporal lobes. The etiology may be idiopathic (cryptogenic partial complex epilepsy) or occur as a secondary manifestation of a focal cortical lesion (symptomatic partial complex epilepsy).

2.4.2 MOTOR PARTIAL EPILEPSY

A disorder characterized by recurrent localized paroxysmal discharges of cerebral neurons that give rise to seizures that have motor manifestations. The majority of partial motor seizures originate in the FRONTAL LOBE (see also EPILEPSY, FRONTAL LOBE). Motor seizures may manifest as tonic or clonic movements involving the face, one limb or one side of the body. A variety of more complex patterns of movement, including abnormal posturing of extremities, may also occur.

2.4.3 SENSORY PARTIAL EPILEPSY

A disorder characterized by recurrent focal onset seizures which have sensory (i.e., olfactory, visual, tactile, gustatory, or auditory) manifestations. Partial seizures that feature alterations of consciousness are referred to as complex partial seizures

2.4.4 FRONTAL LOBE EPILEPSY

A localization-related (focal) form of epilepsy characterized by seizures which arise in the frontal lobe. A variety of clinical syndromes exist depending on the exact location of the seizure focus. Simple or complex motor movements may occur, and most commonly involve the face and upper extremities. Seizures in the anterior frontal regions may be associated with head and eye turning, typically away from the side of origin of the seizure. Frontal lobe seizures may be idiopathic (cryptogenic) or caused by an identifiable disease process such as traumatic injuries, neoplasms, or other macroscopic or microscopic lesions of the frontal lobes (symptomatic frontal lobe seizures).

2.4.5 TEMPORAL LOBE EPIILEPSY

A localization-related (focal) form of epilepsy characterized by recurrent seizures that arise from foci within the temporal lobe, most commonly from its mesial aspect. A wide variety of psychic phenomena may be associated, including illusions, hallucinations, dyscognitive states, and affective experiences. The majority of complex partial seizures (see EPILEPSY, COMPLEX PARTIAL) originate from the temporal lobes. Temporal lobe seizures may be classified by etiolgy as cryptogenic, familial, or symptomatic (i.e., related to an identified disease process or lesion).

2.4.6 ROLANDIC EPILEPSY

An autosomal dominant inherited partial epilepsy syndrome with onset between age 3 and 13 years. Seizures are characterized by PARESTHESIA and tonic or clonic activity of the lower face associated with drooling and dysarthria. The episodes tend to occur at night and may become secondarily generalized. In most cases, affected children are neurologically and developmentally normal. The electroencephalogram shows characteristic high-voltage sharp waves over the central temporal regions, which are more prominent during drowsiness and sleep. In general, seizures do not continue beyond mid-adolescence.

2.5 STATUS EPILEPTICUS

A prolonged seizure or seizures repeated frequently enough to prevent recovery between episodes occurring over a period of 20-30 minutes. The most common subtype is generalized tonic-clonic status epilepticus, a potentially fatal condition associated with neuronal injury and respiratory and metabolic dysfunction. Nonconvulsive forms include petit mal status and complex partial status, which may manifest as behavioral disturbances. Simple partial status epilepticus consists of persistent motor, sensory, or autonomic seizures that do not impair cognition. Subclinical status epilepticus generally refers to seizures occurring in an unresponsive or comatose individual in the absence of overt signs of seizure activity.

2.5.1 EPILEPSIA PARTIALIS CONTINUA

A variant of epilepsy characterized by continuous focal jerking of a body part over a period of hours, days, or even years without spreading to other body regions. Contractions may be aggravated by movement and are reduced, but not abolished during sleep. ELECTROENCEPHALOGRAPHY demonstrates epileptiform (spike and wave) discharges over the hemisphere opposite to the affected limb in most instances. The repetitive movements may originate from the CEREBRAL CORTEX or from subcortical structures (e.g., BRAIN STEM; BASAL GANGLIA). This condition is associated with Russian Spring and Summer encephalitis ; Rasmussen syndrome (see ENCEPHALITIS); MULTIPLE SCLEROSIS; DIABETES MELLITUS; BRAIN NEOPLASMS; and CEREBROVASCULAR DISORDERS.

2.6 BENIGN NEONATAL EPILEPSY

A condition marked by recurrent seizures that occur during the first 4-6 weeks of life despite an otherwise benign neonatal course. Autosomal dominant familial and sporadic forms have been identified. Seizures generally consist of brief episodes of tonic posturing and other movements, apnea, eye deviations, and blood pressure fluctuations. These tend to remit after the 6th week of life. The risk of developing epilepsy at an older age is moderately increased in the familial form of this disorder.

2.7 POST TRAUMATIC EPILEPSY

Recurrent seizures causally related to CRANIOCEREBRAL TRAUMA. Seizure onset may be immediate but is typically delayed for several days after the injury and may not occur for up to two years. The majority of seizures have a focal onset that correlates clinically with the site of brain injury. Cerebral cortex injuries caused by a penetrating foreign object (HEAD INJURIES, PENETRATING) are more likely than closed head injuries (HEAD INJURIES, CLOSED) to be associated with epilepsy. Concussive convulsions are nonepileptic phenomena that occur immediately after head injury and are characterized by tonic and clonic movements.

2.8 REFLEX EPILEPSY

A subtype of epilepsy characterized by seizures that are consistently provoked by a certain specific stimulus. Auditory, visual, and somatosensory stimuli as well as the acts of writing, reading, eating, and decision making are examples of events or activities that may induce seizure activity in affected individuals.

2.9 FEBRILE SEIZURES

Seizures that occur during a febrile episode. It is a common condition, affecting 2-5% of children aged 3 months to five years. An autosomal dominant pattern of inheritance has been identified in some families. The majority are simple febrile seizures (generally defined as generalized onset, single seizures with a duration of less than 30 minutes). Complex febrile seizures are characterized by focal onset, duration greater than 30 minutes, and/or more than one seizure in a 24 hour period. The likelihood of developing epilepsy (i.e., a nonfebrile seizure disorder) following simple febrile seizures is low. Complex febrile seizures are associated with a moderately increased incidence of epilepsy.

2.10 LANDAU-KLEFFNER SYNDROME

A syndrome characterized by the onset of isolated language dysfunction in otherwise normal children (age of onset 4-7 years) and epileptiform discharges on ELECTROENCEPHALOGRAPHY. Seizures, including atypical absence (EPILEPSY, ABSENCE), complex partial (EPILEPSY, COMPLEX PARTIAL), and other types may occur. The electroencephalographic abnormalities and seizures tend to resolve by puberty. The language disorder may also resolve although some individuals are left with severe language dysfunction, including APHASIA and auditory AGNOSIA.

3. CONVULSION
Primarily a lay term. Episodes of excessive, abnormal muscle contractions, usually bilateral, which may be sustained or interrupted. Convulsions may also occur in the absence of an electrical cerebral discharge (e.g., in response to hypotension).

4. ICTAL SEMEIOLOGICAL TERMS
These are descriptors of seizures unless specified otherwise.

5. MOTOR
Involves muscles in any form. The motor event could consist of an increase (positive) or decrease (negative) of muscle contraction or tone to produce a movement.

Unless noted, the following terms are adjectives modifying motor seizure or seizure e.g. tonic motor seizure or dystonic seizure , and whose definitions can usually be understood as prefaced by: refers to ... .

5.1 TONIC
A sustained increase in muscle tone lasting a few seconds to a minute.

5.1.1 SPASM (Formerly Infantile Spasm)
Noun: A sudden flexion, extension or mixed extension-flexion of predominantly muscles close to the trunk which is usually more sustained than a myoclonic movement but not as sustained as a tonic seizure i.e. about 1 sec. Limited forms may occur: grimacing, head nodding.. Epileptic spasms frequently occur in clusters.

5.1.2 POSTURAL
Formation of a posture which may be same on both side of the body or different (as in a fencing posture).

5.1.2.1 VERSIVE
A sustained, forced conjugate ocular, cephalic and/or truncal rotation or lateral deviation from the midline.

5.1.2.2 DYSTONIC
Sustained contractions of opposition muscles producing twisting movements which may produce abnormal postures.

5.2 MYOCLONIC (adjective); MYOCLONUS (noun)
Sudden, brief (< 100 msec) single or multiple contraction(s) of single muscle fibre(s), muscles(s) or muscle groups at variable locations (axial, proximal limb, distal).

5.2.1 NEGATIVE MYOCLONIC
Sudden, brief loss of muscle tone on one side of the body, usually far from the trunk.

5.2.2 CLONIC
Myoclonus which is regularly repetitive and involves the same muscle groups with a frequency of about 2-3 c/sec and is prolonged. Synonym: rhythmic myoclonus.

5.2.2.1 JACKSONIAN MARCH
Noun: Traditional term indicating spread of clonic movements through contiguous (sequential) body parts on one side of the body.

5.2.3 NEGATIVE CLONIC
Regularly repetitive brief losses of muscle tone, e.g. at later phase of motor seizures.

5.3 TONIC-CLONIC
A sequence consisting of a tonic then a clonic phase.

5.3.1 BILATERAL TONIC-CLONIC SEIZURE (Formerly "Generalised Tonic-Clonic" or "Grand Mal" Seizure)
Noun: Bilateral symmetrical tonic contraction then bilateral clonic contractions of somatic muscles (on the head, neck & trunk) usually associated with autonomic phenomena (uncontrolled event).

5.4 ATONIC
Sudden, brief (1-2 sec) loss of muscle tone affecting the posture, and the trunk muscles on one or both sides of the body.

5.5 ASTATIC
Loss of erect posture that results from an atonic, myoclonic or tonic mechanism. Synonym: drop attack.

5.6 SYNCHRONOUS (Asynchronous)
Motor events occurring (not) at the same time or at the same rate in sets of body parts.

5.7 AUTOMATISM
Noun: A more or less coordinated, repetitive, motor activity usually occurring when awareness is impaired and for which the subject is usually amnesic (cannot recall past experience) afterwards. This often resembles a voluntary movement, and may consist of inappropriate continuation of ongoing preictal motor activity.

The following adjectives are usually employed to modify automatism.

5.7.1 OROALIMENTARY
Lip smacking, lip pursing, chewing, licking, tooth grinding or swallowing.

5.7.2 MANUAL OR LIMB
Indicates principally distal components, on one or both side of body.

5.7.3 HYPERKINETIC
Involves predominantly proximal limb or axial muscles producing irregular sequential ballistic movements, such as pedaling, pelvic thrashing, rocking movements.

5.7.4 HYPOKINETIC
A decrease in ongoing motor activity from dialepsis (see below), negative motor event, dysphasia (see below) or dyspraxia (see below).

5.7.4.1 DYSPHASIC
Impaired communication involving language without dysfunction of relevant motor or sensory pathways, manifested as Inability to speak words which one has in mind or to think of correct words, or inability to understand spoken or written words.

5.7.4.2 DYSPRAXIC
Inability to perform learned movements on command or imitation despite intact relevant motor and sensory systems and adequate comprehension and cooperation. Due to impaired or painful function of any organ of the body.

5.7.5 GELASTIC
Bursts of laughter or giggling, usually without an appropriate affective tone.

5.7.6 DACRYSTIC
Bursts of crying.

5.7.7 VOCAL
Single or repetitive utterances consisting of words, sounds or screams. and cooperation.

5.8 AUTONOMIC SEIZURE
An objectively documented and distinct alteration of autonomic nervous system function involving cardiovascular, pupillary, gastrointestinal, sudomotor, vasomotor and thermoregularity functions. (cf. autonomic aura 2.2.2).

6.0 NON-MOTOR SEIZURE COMPONENTS

6.1 DIALEPTIC (Dialepsis, noun)
Impaired awareness of, interaction with, or memory of ongoing events external or internal to the person. Therefore, this phenomenon may be composed of one or more of the following elements:

• mental confusion
• diminished awareness of environment
• inability to respond to external or internal stimuli because of impediments such as dysphasia, dyspraxia, or paresis/paralysis
• amnesia for the event