Figure 2

Scalp HFO rate distribution in presurgical and postsurgical EEG in relation to the skull defect resulting from craniotomy. 3D reconstruction of the skull and the cortical surface generated using the presurgical and postsurgical MRI of patient 12, who had a left temporal ganglioglioma. The spatial distribution of HFO rates in presurgical and postsurgical EEG is depicted using areas marked with different shades of red. Different color intensity corresponds to different HFO rates. HFO area channels are shown in blue, skull defect electrodes in black. (a) In the presurgical scalp EEG, high HFO rates were measured in left temporal channels, matching the location of the HFO area, the epileptogenic zone, and the lesion in the anterior portion of the fusiform gyrus. (b) Given the lesion location, a pterional craniotomy approach (outlined in brown) was chosen to fully resect the epileptogenic zone and lesion. (c) In the postsurgical EEG, HFO rates drastically decreased, in line with postsurgical seizure freedom.