Abstracts

Rationale: It is said that the dense array electroencephalogram (dEEG) has better spatial resolution than the conventional. The purpose of this study is to evaluate the spike detecting ability of the dense array electroencephalogram. Methods: A 21 years old right handed female with right neocortical temporal lobe epilepsy underwent subdural electrodes (SD) insertion, the inter-contacts distances were 1cm, followed by the focus resection over the anterior part of the right superior, middle and inferior temporal lobe. This patient has been seizure free after the surgery. During the subdural electrodes monitoring (SDM) we simultaneously monitored dEEG. We compared the thirty SDM spikes and the same spikes on the dEEG. Results: 83% of the SDM spikes were detected by the dEEG. The SDM spikes were divided into less than 2 contacts, 3 contacts, 4 contacts, 5 contacts, 6contacts, 7contacts, 8contacts, 9 contacts and more than 10 contacts. 55% of the less than 2 contacts of SDM were detected by dEEG. Most of them were from mesial temporal spikes. If more than 3 contacts were involved, the dEEG could detect the spikes with 100%. Conclusions: The dEEG could detect most of the spikes with the order of 2cm. The spike detection rate of 83% is high. However the spikes from mesial structure could not be detected by the dEEG.