title: Adaptive epileptic seizure prediction system.
abstract: Current epileptic seizure "prediction" algorithms are generally based on the knowledge of seizure occurring time and analyze the electroencephalogram (EEG) recordings retrospectively. It is then obvious that, although these analyses provide evidence of brain activity changes prior to epileptic seizures, they cannot be applied to develop implantable devices for diagnostic and therapeutic purposes. In this paper, we describe an adaptive procedure to prospectively analyze continuous, long-term EEG recordings when only the occurring time of the first seizure is known. The algorithm is based on the convergence and divergence of short-term maximum Lyapunov exponents (STLmax) among critical electrode sites selected adaptively. A warning of an impending seizure is then issued. Global optimization techniques are applied for selecting the critical groups of electrode sites. The adaptive seizure prediction algorithm (ASPA) was tested in continuous 0.76 to 5.84 days intracranial EEG recordings from a group of five patients with refractory temporal lobe epilepsy. A fixed parameter setting applied to all cases predicted 82% of seizures with a false prediction rate of 0.16/h. Seizure warnings occurred an average of 71.7 min before ictal onset. Similar results were produced by dividing the available EEG recordings into half training and testing portions. Optimizing the parameters for individual patients improved sensitivity (84% overall) and reduced false prediction rate (0.12/h overall). These results indicate that ASPA can be applied to implantable devices for diagnostic and therapeutic purposes.
authors.affiliation: Harrington Department of Bioengineering, the Center for Systems Science and Engineering Research, Arizona State University, Tempe, AZ 85287-9709, USA. leon.iasemidis@asu.edu
authors.forename: Leon D
authors.initials: LD
authors.lastname: Iasemidis
authors.forename: Deng-Shan
authors.initials: DS
authors.lastname: Shiau
authors.forename: Wanpracha
authors.initials: W
authors.lastname: Chaovalitwongse
authors.forename: J Chris
authors.initials: JC
authors.lastname: Sackellares
authors.forename: Panos M
authors.initials: PM
authors.lastname: Pardalos
authors.forename: Jose C
authors.initials: JC
authors.lastname: Principe
authors.forename: Paul R
authors.initials: PR
authors.lastname: Carney
authors.forename: Awadhesh
authors.initials: A
authors.lastname: Prasad
authors.forename: Balaji
authors.initials: B
authors.lastname: Veeramani
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Tsakalis
mesh_terms: D000465:Algorithms; D001931:Brain Mapping / Q000379:methods; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000379:methods*; D004827:Epilepsy / Q000175:diagnosis / Q000503:physiopathology; D005189:False Positive Reactions; D005246:Feedback; D005625:Frontal Lobe / Q000503:physiopathology; D006624:Hippocampus / Q000503:physiopathology; D006801:Humans; D018670:Monitoring, Ambulatory / Q000379:methods; D011786:Quality Control; D015203:Reproducibility of Results; D012640:Seizures / Q000175:diagnosis* / Q000503:physiopathology; D012680:Sensitivity and Specificity; D013702:Temporal Lobe / Q000503:physiopathology