J Korean Neurol Assoc.  1996 Jun;14(2):425-432.

Correlation between Preexcision ECoG Patterns and MRI Findings and Clinical Significance of Postexcision ECoG after Temporal Lobectomy

• Kang JK
• Hwang YM

Abstract

Role of intraoperative ECoG is uncertain and still controversial. We investigated the correlation of preexcision ECoG (pre-ECoG) patterns with MRI findings and the correlation of the presence or absence of residual spikes in postexcision ECoG (post-ECoG) with surgical outcome. We retrospectively studied 29 temporal lobectomized patients (follow-up period: > 16 mons). The ECoG was performed using two subdural strips on the mesiobasal and lateral temporal lobe. Topography and frequency of epileptiform discharges (ED) in pre-ECoG were analyzed and correlated with hippocampal atrophy only or hippocampal and lateral temporal atrophy in MRI. Among the 15 patients with hippocampal atrophy only, pre-ECoG showed mesial temporal dominant ED in 8 ( 53.3 %), diffuse ED in 3 ( 20.0 %) and lateral temporal dominant ED in 4 ( 26.7 %). In 14 patients with hippocampal and lateral temporal atrophy, mesial temporal dominant ED showed in 2 ( 14.3%), diffuse ED in 8 ( 57.1 %), and lateral temporal dominant ED in 4 ( 28.6%). Compared to patients with hippocampal atrophy only, there was statistically significant widespread epilepiiform discharges on the mesial and lateral temporal area in patients with hippocampal and lateral temporal atrophy( p<0.05 ). All of 6 patients without residual spikes and 19 out of 23 patients with residual spikes in post-ECoG were seizure free or aura only after surgery. But presence or absence of residual spikes post-ECoG is not statistically correlated with surgical outcome (p>0.3).

MeSH Terms

Atrophy
Epilepsy
Humans
Magnetic Resonance Imaging*
Retrospective Studies
Seizures
Temporal Lobe