Localization of focal cerebral ischemia by Karhunen-Loeve transform of the EEG

摘要

The electroencephalogram has important diagnostic value when cerebral perfusion is disturbed. An important field of EEG examination is the localization of the focal ischemic area of the brain. In this case we have to take into consideration that there is no control or baseline data to make a comparison, and that collateral circulation may as well compensate the acute effects of the lack of blood supply. A method based on Karhunen-Loeve transform is presented, which shows good results in localising ischemia as characterized by similarity of the signals over several channels.