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Medical Term:


Pronunciation: ahb-sahns′

Definition: Paroxysmal attacks of impaired consciousness, occasionally accompanied by spasm or twitching of cephalic muscles, which usually can be brought on by hyperventilation; depending on the type and severity of the absence, the EEG may show an abrupt onset of a 3-second spike-and-wave pattern as in simple absence, or in atypical cases a 4-second spike-and-wave or faster spike complexes. The clinical states accompanying these EEG abnormalities may be classified as: 1) absence with no overt manifestations, simple absence; epileptic absence; subclinical absence; 2) absence with clonic movements, myoclonic absence; 3) absence with atonic states, atonic absence; 4) absence with tonic contractions, hypertonic muscular contraction; 5) absence with automatisms, various stereotypic movements, usually of the face or hands; 6) absence with atypical features, bizarre motor activity.

[L. absentia]

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.