Postmortem analysis of bilateral subthalamic electrode implants in Parkinson's disease

Abstract

This is the second neuropathological report detailing bilateral electrodes targeting the subthalamic nucleus (STN) in idiopathic Parkinson's disease (PD). The patient presented with unilateral tremor-dominant parkinsonism. Bilateral STN stimulation was carried out 7 years later due to significant disease progression and severe motor fluctuations. The patient exhibited bilateral improvements in rigidity and bradykinesia both intraoperatively and postoperatively. The patient died 2 months later from aspiration pneumonia. Neuropathological examination confirmed both the diagnosis of PD and the electrode placements. The tip of the left electrode was located medially and posteriorly in the left STN and the tip of the right electrode entered the base of the thalamus/zona incerta immediately above the right STN. Tissue changes associated with the subthalamic electrode tracts included mild cell loss, astrogliosis, and some tissue vacuolation. Our postmortem analysis indicates little tissue damage associated with STN stimulation for PD.

Asymptomatic Transient MRI Signal Changes after Unilateral Deep Brain Stimulation Electrode Implantation for Movement Disorder

“…Reports examining the postmortem brain parenchyma around a DBS electrode in subcortical targets long after implantation have concluded that no serious histopathological complications are seen after chronic electrical stimulation irrespective of the amount of stimulation [3,[5][6][7][8]. For example, Burbaud et al [8] found focal astrocytic gliosis and mild leukocytic infiltration in the chronic track of two bilateral DBS electrodes implanted about 2 years before death.…”

“…There have been five autopsy studies on patients treated with DBS to assess the long-term effect of stimulation electrodes on brain tissue [3,[5][6][7][8]. In the largest of these, 8 postmortem brains of patients with DBS implanted for Parkinson's disease all had well-preserved neural parenchyma with only mild gliosis around the lead track, compatible with reactive changes due to surgical placement of the electrode [6].…”

“…Though its efficacy has been confirmed, recent interest has focused on complications associated with DBS placement. Infection, hardware failure and brain injury have been documented to varying degrees in patients who present with complications [2,3]. However, whether physiologic changes are directly attributable to the presence of a DBS electrode in the brain matter is unknown [4].…”

Acute and Subacute Presentations of Cerebral Edema following Deep Brain Stimulation Lead Implantation

“…Such absence of permanent sequelae as well as location of edema isolated at the tip, perilead or subcortically makes it unlikely to be due to a venous infarct, which has typical imaging characteristics showing cortical wedge-shaped ischemia [1,10]. Very likely, mechanical trauma due to microelectrode and DBS lead insertion disrupts the blood-brain barrier to some extent, which could result in the possibility of “luxury perfusion” [1,2,15]. Why this leads to such clinical presentations seen in a small subset of patients herein is curious, as it is unclear why such an occurrence remains predominantly unilateral despite bilateral implantation, here and in other series [1,2].…”

Early Primary Biliary Cholangitis is Characterised by Brain Abnormalities on Cerebral Magnetic Resonance Imaging

“…The study of patients with early disease is warranted to explore the hypothesis that brain change starts early in the disease; a finding which if confirmed would warrant a change in proposed treatment paradigms. The basal ganglia and the globus pallidus in particular are key regions of the brain with associated pathophysiology in a variety of conditions ranging from movement disorders, such as Parkinson's disease 14 to chronic hepatitis C, and in manganese workers, who have been exposed to industrial pollution. [15][16][17] It has been previously hypothesised that disrupted activity in these areas of the brain leads to decreased motivation in these conditions, perceived by the individual as fatigue.…”