MOTOR CORTEX EXCITABILITY CHANGES IN UNTREATED PATIENTS WITH EPILEPSY BEFORE AND AFTER SLEEP DEPRIVATION
Abstract number :
1.142
Submission category :
Year :
2002
Submission ID :
1870
Source :
www.aesnet.org
Presentation date :
12/7/2002 12:00:00 AM
Published date :
Dec 1, 2002, 06:00 AM
Authors :
Ewa Slusarska, Krystyna Niedzielska, Maria Niewiadomska, Maria Baranska-Gieruszczak, Wanda Lojkowska, Czeslaw Glazowski, Waldemar Lechowicz, Joanna Lecka, Danuta Ryglewicz. Ist Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland
RATIONALE: Sleep deprivation (SD) prior to recording is a well known method of activation of epileptic discharges. However, its physiological mechanism is still not clear and might be connected with the changes of cortical excitability. Transcranial magnetic stimulation (TMS) can give information about the level of cortical excitability and inhibition.
The aim of the study was to assess the influence of SD on the cortex motor threshold (MT) and cortical silent period (CSP) evoked by TMS in untreated patients with epilepsy.
METHODS: We studied 7 patients (aged 17 to 39; 5 men, 2 women) with a history of at least two seizures. None of them had taken anti-epileptic drugs. TMS was performed using Magstim model 200. MT and CSP were estimated by applying single puls technique. The values of MT and CSP were assessed before and after sleep deprivation. The MT measures were compared with 30 normal control subjects. In all patients routine EEG and EEG after SD immediately before TMS was performed.
RESULTS: Routine EEG examination revealed changes in six patients: bilateral groups of theta waves in fronto-temporal or occipito-temporal areas in five patients with sharp waves in one case, and generalized spike-wave discharges in one patient. After SD in EEGs of two patients focal sharp waves appeared and in two other patients the enhancement of pre-existing discharges were observed. The mean MT values for the left and right hemisphere before SD (mean 45.8 [plusminus] 8.8) and after SD (mean 46.6 [plusminus] 10.3) did not change significantly
(p=0.875), as well as there were no significant differences in mean MT values in epileptic group before and after SD compared with healthy controls (mean 47.15, p=0.59)
The mean CSP duration increased after SD from 181.5 ms to 190.2 ms, but this difference was not significant (p=0.432). Prolonged CSPs were found in all patients with activation of epileptic discharges after SD.
CONCLUSIONS: In untreated epileptic patients MTs and CSPs values established with TMS did not change significantly after SD. However CSPs duration were increased especially in patients with activation after SD. These preliminary observations should be confirmed in larger series and in relation to the specific epileptic syndrome.
[Supported by: National Commitee Of Research]