Postmortem observation of collagenous lead tip region fibrosis as a rare complication of DBS

Background: Despite the widespread effective use of deep brain stimulation (DBS) for various movement and psychiatric disorders, little is known about its safety and tissue responses. Methods: The University of Florida Deep Brain Stimulation Brain Tissue Network (DBS‐BTN) conducted postmortem brain examinations on 26 cases to identify and characterize (using histological techniques) pathologic tissue changes associated with the placement of DBS devices. Results: We report the unusual finding of prominent collagenous fibrosis around the lead tip in a 74‐year‐old man with idiopathic Parkinson's disease who had bilateral STN‐DBS. Histological study confirmed the diagnosis of idiopathic Parkinson's disease, and there was striking, dense collagenous fibrosis at the distal end of the right DBS lead associated with focal hemosiderin deposition, chronic inflammation, and mild gliosis. We have in our brain bank 25 other DBS cases that on examination showed only mild to moderate gliosis and no dramatic tissue response to DBS lead placement. Conclusions: We are not aware of any prior reports of such a dramatic reaction to DBS placement to date. © 2012 Movement Disorder Society