Intermediate
Technical
In the Industry Vocabulary Test
Atonic seizure
Pronunciation: ay-TON-ik
A seizure type characterized by sudden loss of muscle tone, often resulting in falls or drop attacks.
Full Definition
Atonic seizures involve a sudden loss or diminution of muscle tone, lasting 1-3 seconds. They typically affect postural muscles and can result in head drops, jaw drops, or complete falls ('drop attacks'). These seizures are most commonly seen in childhood epilepsy syndromes such as Lennox-Gastaut syndrome and Doose syndrome. The loss of tone can be partial (affecting only certain muscle groups) or generalized (causing complete collapse), and patients may injure themselves due to sudden falls.
Usage
Usage note: Distinguish from akinetic seizures, though the terms are sometimes used interchangeably in older literature.
In Context
- "The child required a protective helmet due to frequent atonic seizures causing head trauma." — Pediatric epilepsy clinic note
- "Atonic seizures in Lennox-Gastaut syndrome often prove resistant to conventional anticonvulsants." — Medical literature review
Also known as
drop attack
akinetic seizure
Contrasted with
tonic seizure
Don't confuse with
syncope
cataplexy
falling episodes