Effect of cortical cooling on interictal epileptiform activities.

Objective: To determine if applying chilled solution to exposed cerebral cortex can reduce interictal epileptiform activities in patients during surgery.

Methods: Electrocorticography was used to record the epileptiform activity of 12 patients (ages 18-53) undergoing cortical mapping and resection surgery. Interictal spikes were counted at baseline and compared with spikes after applying room temperature and chilled Lactated Ringer's or normal saline solution.

Results: Cortical irrigation with 150-cm(3), chilled (4 degrees C) normal saline solution reduced the mean number of interictal spikes from 11.46 to 4.87 spikes per minute (p=0.04). There was no significant reduction in the epileptic spike frequency when room temperature normal saline was used.

Conclusion: The application of chilled solution directly to the cortex can reduce interictal epileptiform activities, suggesting that seizure potential can be suppressed to avoid evoked seizures during intraoperative surgery.