Cerebral Tissue Response to Electrode Implantation

Abstract

SUMMARY:Tissue response to platinum electrodes was assessed after an eight-day implantation period. The regions of study included the cortical areas at the opercular gyri and at the sulcus parielo-occipitalis externus, as well as the sub-cortical white matter in these areas.Perivascular and intraparenchymal hemorrhagic lesions as well as edematous changes characterized both by extensive intra and extracellular swelling were noted. Numerous phagocytic elements and degenerative structures were present at the electrode I parenchymal interface.Tissue alterations were asymmetrical as observed both around and at the lip of the implanted electrode. The parenchymal alterations extended from 0.2mm to 3.5mm distance from the electrode path/ parenchymal interface.Greater tissue involvement was found in the subcortical white matter as compared to the adjacent cortical gray matter.