Summary
An innovative method for on-line processing of array ECoG data, the Spatio-Temporal Laplacian, intended for intraoperative epileptic focus localization is presented. This method simultaneously involves the spatial and temporal characteristics of the potential field manifestations peculiar to focal interictal events. A 3-Dimensional (x, y and t) sample space is used to explain and apply the Spatio-Temporal Laplacian (STL) transformation. In particular, a focal interictal event is detected through the coincident spatial and temporal sharpness that it introduces in this sample space. Preliminary results from two subjects are presented and compared with standard bipolar derivation signals, traditionally used in the focus localization task.
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The authors would like to acknowledge Dr. Bruce Richards and Ms. Jerline White for giving us access to the ECoG data used in our studies and for their assistance in designing the montages for the array and interfacing the EEG machine with our recording equipment. We would also like to thank the Neuroscience Institute for their cooperation with these studies.
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Barreto, A.B., Principe, J.C. & Reid, S.A. STL: A Spatio-Temporal characterization of focal interictal events. Brain Topogr 5, 215–228 (1993). https://doi.org/10.1007/BF01128989
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DOI: https://doi.org/10.1007/BF01128989