Spike and wave
Spike-and-wave discharges are a pattern of the electroencephalogram (EEG) typically observed in various types of epilepsy, most notably in absence seizures. This pattern is characterized by a high-amplitude electrical spike followed by a slower wave, usually occurring at a frequency of 3 Hz in classic absence epilepsy, but frequencies can vary. The spike-and-wave pattern is crucial for the diagnosis and understanding of certain epileptic conditions and reflects the underlying synchronized neuronal activity in the brain.
Characteristics[edit | edit source]
Spike-and-wave discharges are defined by their distinct pattern on an EEG recording. The "spike" component is a rapid, high-voltage electrical signal that lasts for less than 70 milliseconds. It is followed by the "wave" component, a slower, larger wave of electrical activity that lasts for more than 70 milliseconds. This pattern can occur sporadically or at regular intervals and is often bilateral and symmetric across both hemispheres of the brain.
Pathophysiology[edit | edit source]
The exact mechanism behind spike-and-wave discharges is complex and involves the thalamocortical network, which includes both the thalamus and the cortex. These discharges are believed to result from the interaction between the inhibitory and excitatory neurons in these regions, leading to a synchronized burst of neuronal activity. This synchronization is thought to be the result of a temporary imbalance between the excitatory neurotransmitter glutamate and the inhibitory neurotransmitter GABA (gamma-aminobutyric acid).
Clinical Significance[edit | edit source]
Spike-and-wave discharges are most commonly associated with absence seizures, a type of generalized seizure that leads to brief lapses in consciousness without convulsive movements. These discharges can also be seen in other types of epilepsy and are an important marker for diagnosis and treatment planning. The presence of spike-and-wave patterns on an EEG can help differentiate between different types of epileptic syndromes and guide the selection of appropriate anti-epileptic drugs.
Diagnosis[edit | edit source]
The diagnosis of conditions associated with spike-and-wave discharges primarily involves the use of EEG. During an EEG, electrodes placed on the scalp measure electrical activity in the brain. The presence of characteristic spike-and-wave patterns, especially when correlated with clinical symptoms such as brief staring spells, supports the diagnosis of absence epilepsy or other related epileptic syndromes.
Treatment[edit | edit source]
Treatment for conditions characterized by spike-and-wave discharges typically involves anti-epileptic drugs (AEDs) that help to balance the excitatory and inhibitory forces within the brain, thereby reducing the frequency of discharges and associated seizures. The choice of medication depends on the specific type of epilepsy and the patient's response to treatment. In some cases, lifestyle changes, dietary adjustments, or surgery may be recommended.
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
WikiMD's Wellness Encyclopedia |
Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD