Fast Automatic Localization of Epileptic Seizure Onset Zones Using Complex Morlet Wavelet Transform-based Singular Value Decomposition

A new method for localization of epileptic seizure onset zones (SOZs) is proposed, which uses the Shannon-entropy-based complex Morlet wavelet transform to extract a satisfactory time-frequency feature of high-frequency oscillations (HFOs). The singular value decomposition and the K-medoids clustering algorithm are employed to extract effective features from the redundant matrix of wavelet coefficients. A distinctive feature is to use the singular values to detect HFOs with the consideration that the singular values of HFOs are generally significantly higher than those of normal case. Based on the half-maximum method, the localization of SOZs are achieved by using the characteristics of HFOs. Comparisons show that our method provides a higher sensitivity and specificity than two existing methods do.