atonic seizure

(redirected from Atonic Seizures)


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.

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
References in periodicals archive ?
For the 11 people with Lennox-Gastaut syndrome who finished the study, there was a 55 percent reduction in the number of atonic seizures, which cause a sudden loss of muscle tone.
The most common seizure types associated with LGS, tonic and atonic seizures, lead to frequent falls due to sudden loss of consciousness.
Simultaneous recording of 2 episodes by EEG, videography, electromyography, and electrocardiography documented that the nodding episodes are manifestations of atonic seizures.
generalised seizures including tonic, clonic, tonic-clonic, absence, myoclonic and atonic seizures and infantile spasms
But, most commonly, Tom suffers atonic seizures, where he just falls to the ground because every muscle in his body relaxes.
Other types of generalized seizures are: tonic seizures which involve muscie rigidity but are not followed by a clonic phase; clonic seizures which involve violent rhythmic contractions but is not preceded by tonic phase; myoclonic seizures in which a person has brief involuntary jerking of the torso or extremities; and atonic seizures in which the skeletal muscles lose all tone causing the person to suddenly drop to the floor.
Not to mention, he started to experience, at the time, what are called atonic seizures (drop-attack seizures of paralysis).
Falling is the main concern with generalized tonic-clonic seizures (either primary or partial seizures that secondarily generalize) and atonic seizures.
Tonic and atonic seizures, also known as "drop attacks," cause the body to fall uncontrollably, and are a primary cause of facial and head injuries as well as lacerations that can leave disfiguring scars.
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.
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.