hypsarrhythmia


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hypsarrhythmia

 [hip″sah-rith´me-ah]
a term for an electroencephalographic abnormality sometimes observed in infants, with random high-voltage slow waves and spikes arising from multiple foci and spreading to all cortical areas; the disorder is characterized by spasms or quivering spells, and is commonly associated with mental retardation.

hyp·sa·rhyth·mi·a

, hypsarrhythmia (hip'să-rith'mē-ă),
The abnormal and characteristically chaotic electroencephalogram commonly found in patients with infantile spasms.
[G. hypsi, high, + a- priv. + rhythmos, rhythm]

hypsarrhythmia

/hyp·sar·rhyth·mia/ (hip″sah-rith´me-ah) an electroencephalographic abnormality commonly associated with jackknife seizures, with random, high-voltage slow waves and spikes spreading to all cortical areas.

hypsarrhythmia

(hĭp″săr-ĭth′mē-ă) [Gr. hypsi, high, + a-, not, + rhythmos, rhythm]
An abnormal electroencephalographic pattern of persistent generalized slow waves and very high voltage. Clinically it is often associated with infantile spasm and progressive mental deterioration.
References in periodicals archive ?
In our study eight infants presented as hypsarrhythmia background pattern on vEEG, but the aEEG background of them showed persistent high voltage activities and covered up the actual seizure activities [Figure 4].
1] It is an epileptic encephalopathy characterised by epileptic spasms, electroencephalographic (EEG) evidence of hypsarrhythmia and developmental delay or regression.
Five infants initially had hypsarrhythmia, indicating highly disorganized brain activity, and had spasms and neuromotor delays.
EEG was evaluated for abnormalities of background, spikes, polyspikes, slowing, hypsarrhythmia and EEG pattern specific for any specific syndrome were looked.
Hypsarrhythmia pattern was observed on electroencephalogram (EEG) and synthetic adrenocorticotropic hormone (ACTH) treatment was initiated (Figure 1).
For instance, infantile spasms and hypsarrhythmia have been classically known as a generalized epilepsy syndrome, however, advances in imaging methods and video-EEG showed us that this condition may occur due to focal cortical dysplasia and surgical excision may enable both seizure control and improve generalized EEG pattern (25,26).
If they are recognized within 4-6 weeks of onset, the ability to eliminate the infantile spasms and hypsarrhythmia EEG pattern is improved.
Not all patients with IS show hypsarrhythmia on EEG.
Children with suspected infantile spasms should have an initial awake EEG as the pathognomonic finding of hypsarrhythmia may be attenuated in the sleeping infant.
Thus, unlike all treatments for other seizure types, success in the treatment of IS requires an "all or nothing" approach, that is, no spasms and resolution of hypsarrhythmia.
Electroencephalography showed abnormal results in 62% of patients, including focal abnormalities, hypsarrhythmia, and generalized spikes.
Infantile spasms are characterized by seizures, hypsarrhythmia (abnormal, chaotic brain wave patterns), and mental retardation.