Closed-loop seizure control on epileptic rat models

Abstract

In this paper numerous alternative treatments in addition to pharmacological therapy are proposed for their use in epileptic patients. Epileptic animal models can play a crucial role in the performance evaluation of new therapeutic techniques. The objective of this research is to first develop various epileptic rat models; second, develop a portable wireless closed-loop seizure controller including on-line seizure detection and real-time electrical stimulation for seizure elimination; and third, apply the developed seizure controller to the animal models to perform on-line seizure elimination. The closed-loop seizure controller was applied to three Long-Evans rats with spontaneous spike-wave discharges (non-convulsive) and three Long-Evans rats with epileptiform activities induced by pentylenetetrazol (PTZ) injection (convulsive) for evaluation. The seizure detection accuracy is greater than 92% (up to 99%), and averaged seizure detection latency is less than 0.6 s for both spontaneous non-convulsive and PTZ-induced convulsive seizures. The average false stimulation rate is 3.1%. Near 30% of PTZ-induced convulsive seizures need more than two times of 0.5 s electrical stimulation for suppression and 90% of the non-convulsive seizures can be suppressed by only one 0.5 s electrical stimulation.

Methods of automated absence seizure detection, interference by stimulation, and possibilities for prediction in genetic absence models

“…A combination of approximate entropy and the power of two selected frequency bands (intraspike frequency and first harmonic) of the ECoG of the frontal barrel cortex filtered between 0.32 and 80 Hz, sampled at 200s/sec was used by Liang et al (2011) to detect seizure activity in an epilepsy model (Long-Evans rats with spontaneous non-convulsive SWDs) and in a seizure model (the proconvulsant PTZ (20 mg/kg i.p.) was injected into Long-Evans rats to provoke SWD).…”

“…for executing a seizure detection algorithm and generating pulse trains and wireless transmission on the animals head was used to evaluate the efficacy of the system in interrupting SWDs. The animal model in which the system was evaluated were Long-Evans rats, either with spontaneous SWDs or after PTZ-M a n u s c r i p t administration (Liang et al, 2011). Stimulation parameters were 800 Hz, 0.5 sec pulse train, pulse duration 0.5 msec, 30-40 microA, the zone inserta was stimulated.…”

A Versatile Wireless Portable Monitoring System for Brain–Behavior Approaches

“…The number of recording channels required in a study depends on the problem to be investigated. For example, online detection of absence seizure can be achieved by using a single EEG channel [32], [33]. However, all of the seven recording channels were used when monitoring a fully kindled TLE in this paper.…”

Future of Seizure Prediction and Intervention

“…Only after many years of testing and validation are we beginning to see some of the first commercial endeavors making ICs dedicated for physiology recording (www.intantech.com). Another avenue for device development is to use commercial off-the-shelf components (COTS)(Liang et al 2011; Salam et al 2012) or modify existing platforms (Stanslaski et al 2012). While ICs are considered the gold standard of circuit design and will always produce the smallest and lowest power systems, COTS parts provide the necessary robust performance.…”