Abstracts

Nonlinear Dynamic Characteristics of EEG Stage in Pilocarpine-Induced Status Epilepticus Model.

Abstract number : 1.115
Submission category :
Year : 2001
Submission ID : 288
Source : www.aesnet.org
Presentation date : 12/1/2001 12:00:00 AM
Published date : Dec 1, 2001, 06:00 AM

Authors :
K-Y. Jung, M.D., Neurology, College of Medicine, Taejon, Republic of Korea; J.M. Kim, M.D., Neurology, College of Medicine, Chungnam National University, Taejon, Republic of Korea; D.W. Kim, M.D., Pediatrics, Ilsan Paik Hospital, Inje University, Ilsan, R

RATIONALE: Pilocarpine-induced status epilepticus(SE) model show stereotypic EEG changes and behavioral characteristics. Although neuronal damages and therapeutic responses are also dependent on SE stage, the dynamical aspect of underlying neuronal interaction according to SE stages has not been studied. The authors applied nonlinear analysis to EEG from pilocarpine-induced SE model to characterize nonlinear dynamics according to SE stage and to correlate therapeutic response with correlation dimension(D2).
METHODS: Ten male Spraw-Daley rats weighing 150-250 g were used in this experiment. EEG was continuously recorded during SE and was classified into 6 stages adapted from Treimann et al.(1990) as follows; baseline(BS), transitional(TR), discrete seizure(DS), continuous ictal discharges(CID), early periodic epileptiform discharges(EP), and late periodic epileptiform discharges(LP). High dose diazepam(20 mg/kg) was injected at LP stage. SEs of 5 rats(controlled group) were controlled by diazepam and the rest(failed group) were failed to stop status epilepticus.
RESULTS: Mean D2 value decreased progressively with fluctuation and was significantly different for SE stage(df=5, F=11.594, p=0.000). Univariate analysis showed the difference of D2 value between controlled and failed group was also significant(dF=2.677, p=0.023) at CID and LP stage.
CONCLUSIONS: These results suggest that nonlinear dynamical change at late half of SE stage is one of contributing factors determining therapeutic responsiveness in pilocarpine-induced SE model.
Support: This study was supported by a grant of the Korea Health 21 R&D Project, [ssquote]Ministry of Health and Welfare[ssquote], Republic of Korea. (HNP-99-N-02-0003)