atonic seizure

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1. the sudden attack or recurrence of a disease.
2. a convulsion or attack of epilepsy.
absence seizure the seizure seen in petit mal epilepsy, marked by a momentary break in the stream of thought and activity, accompanied by a symmetrical spike and wave at 3 cycles per second on the electroencephalogram. Called also petit malseizure. See epilepsy.
atonic seizure an absence seizure characterized by sudden loss of muscle tone.
complex partial seizure see partial seizure.
febrile seizure febrile convulsion.
focal seizure partial seizure.
focal motor seizure a simple partial seizure consisting of clonus or spasm of a muscle or muscle group, occurring either singly or in a continuous repetitive series.
generalized tonic-clonic seizure (grand mal seizure) the seizure seen in grand mal epilepsy, marked by loss of consciousness and generalized tonic convulsions followed by clonic convulsions. See epilepsy.
jackknife s's infantile spasms.
myoclonic seizure one characterized by a brief episode of myoclonus.
partial seizure any seizure due to a lesion in a specific, known area of the cerebral cortex; symptoms vary with different lesion locations. A simple partial seizure is the most localized type, with a discharge that is predominantly one-sided or presents localized features without loss of consciousness. A complex partial seizure is associated with disease of the temporal lobe and characterized by varying degrees of impairment of consciousness. See epilepsy.
petit mal seizure absence seizure.
reflex seizure (sensory seizure) an epileptic seizure in response to a sensory stimulus, which may be tactile, visual, auditory, or musical.
simple partial seizure see partial seizure.
tonic-clonic seizure see generalized tonic-clonic seizure.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

a·ton·ic sei·zure

a seizure characterized by sudden, brief (1-2 second) loss of muscle tone, involving postural muscles; the term usually applies to bilaterally synchronous events.
Synonym(s): akinetic seizure
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Furthermore, with patients prone to frequent falls due to sudden losses of consciousness caused by the tonic and atonic seizures associated with LGS, and with this form of epilepsy often also leading to delayed intellectual development and behavioral disturbances, the disorder significantly impacts on the quality of life of patients and their families.
Falling is the main concern with generalized tonic-clonic seizures (either primary or partial seizures that secondarily generalize) and atonic seizures. Over 60% of seizure-related falls in the Johns Hopkins EMU result in injury such as abrasions and contusions of the extremities or head.
Her abnormal movements were noted to be myoclonic jerks and atonic seizures which manifested as 'head nods'.
ATONIC SEIZURES: Atonic seizures are the opposite of tonic seizures and all the muscles in the body suddenly go floppy.
In the follow-up, partial seizures were observed in 20 of the patients (95.2%), infantile spasms were observed in 8 patients (38%), diffuse tonic-clonic seizures were observed in three patients (14.2%), atonic seizures were observed in three patients (14.2%) and absence seizures were observed in one patient (4.7%).
Tonic-clonic and atonic seizures were the most common seizure types in these patients.
The most common seizure types associated with LGS, tonic and atonic seizures, lead to frequent falls due to sudden loss of consciousness.
Atonic seizures (Drop Attacks) are epileptic events in which the individual loses body tone and consciousness acutely causing the body to drop and fall which can result in severe bodily injury.
Atonic seizures. Pediatrics in Review, 9(2), 43-49.