Motor cortical thresholds and cortical silent periods in epilepsy

• Published in: Seizure (London, England) Vol. 13; no. 7; pp. 481 - 485
• Main Authors: Tataroglu, Cengiz, Ozkiziltan, Safa, Baklan, Baris
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-10-2004
• Subjects: Adolescent; Adult; Anticonvulsants - therapeutic use; Child; Electric Stimulation - methods; Electroencephalography - drug effects; Electroencephalography - methods; Electroencephalography - radiation effects; Epilepsy; Epilepsy - physiopathology; Epilepsy - therapy; Female; Humans; Magnetics; Male; Middle Aged; Motor Cortex - drug effects; Motor Cortex - physiopathology; Motor Cortex - radiation effects; Reaction Time - drug effects; Reaction Time - radiation effects; Refractory Period, Electrophysiological; Sensory Thresholds - drug effects; Sensory Thresholds - radiation effects; Silent period; Statistics, Nonparametric; Threshold intensity; Transcranial magnetic stimulation; Transcranial magnetic stimulation; Silent period; Epilepsy; Threshold intensity
• ISSN: 1059-1311; 1532-2688
• DOI: 10.1016/j.seizure.2003.11.003

We studied motor cortical thresholds (TIs) and cortical silent periods (SPs) evoked by transcranial magnetic stimulation (TMS) in 110 epileptic patients. Sixty-two had primary generalised, 48 had partial type seizures. Fifteen out 110 patients were analysed both before and after anticonvulsant medication. Our aims were to evaluate the TI levels and the duration of SPs in patients with epilepsy and to determine the reliability of TMS in patients with epilepsy. There was no negative effect of TMS on the clinical status and EEG findings in patients with epilepsy. TIs obtained from patients with partial epilepsy were higher than those obtained from both controls and primary epileptics. The duration of SP in patients with primary epileptics was more prolonged than those obtained from controls. There was no correlation between EEG lateralisation and both SP duration and TI values. In de novo patient group, SP duration was significantly prolonged after anticonvulsant medication. We concluded that TMS is a reliable electrophysiological investigation in patients with epilepsy. The analysis of SP duration may be an appropriate investigation in monitoring the effect of anticonvulsant medication on the cortical inhibitory activity.