Session Information
Date: Monday, June 20, 2016
Session Title: Surgical therapy: Parkinson's disease
Session Time: 12:30pm-2:00pm
Location: Exhibit Hall located in Hall B, Level 2
Objective: To characterize the electrophysiological activity of the subthalamic nucleus (STN) functional subterritories, as anatomically defined on fused CT/MRI images or by the recording tract itself, in subject with Parkinson’s disease (PD).
Background: Deep brain stimulation (DBS) of the STN is an established treatment for advanced PD. Intraoperative micro-electrode recording (MER) allows the precise targeting of the STN and the study of its electrophysiological activity. The STN is functionally divided into different subterritories: sensorimotor, limbic, and associative domain, located in its dorsolateral (dSTN), ventral (vSTN) and medial part, respectively. The precise targeting of the STN is crucial for an effective stimulation and to avoid possible side effects. However, a different electrophysiological activity across STN functional domains is still controversial.
Methods: We analysed MER of 31 PD patients implanted for STN-DBS. Recordings were assigned to dSTN or vSTN according (1) to a tri-segmented partition based on recordings themselves and (2) to an anatomically based method defined on CT/MRI images. Only stable recording were analysed and we computed: (i) the inter-spike interval (ISI); (ii) ISI-characteristics; (iii) mean firing rate (MFR); (iv) discharge patterns and, (v) mean burst rate (MBR) of each detected single unit activity. Before and 1-year after surgery, we evaluated motor symptoms and dopaminergic treatment by means of Unified Parkinson’s disease Rating Scale motor part (UPDRS-III) and levodopa equivalent daily dose (LEDD), respectively.
Results: All patients clinically improved after STN-DBS (-42% of UPDRS-III score and LEDD). With the anatomically based method we found a significant difference in MBR (dSTN: 1.51±0.18; vSTN: 1.76±0.22, Wilcoxon ranksum test, p<0.05) and a trend in MFR (dSTN: 12.78 and vSTN: 15.05Hz, Wilcoxon ranksum test, p=0.053). These findings were not mirrored by the tripartite method, despite similar ISI and ISI-characteristics.
Conclusions: Our study suggests that different functions of STN subterritories may be encoded in specific bursting signalling rather than different discharge rates. These findings might improve DBS placing and programming.
To cite this abstract in AMA style:
N.G. Pozzi, G. Arnulfo, F. Steigerwald, A. Canessa, R. Nickl, C. Matthies, J. Volkmann, I.U. Isaias. Electrophysiological activity of anatomically identified STN subterritories in Parkinson’s disease [abstract]. Mov Disord. 2016; 31 (suppl 2). https://www.mdsabstracts.org/abstract/electrophysiological-activity-of-anatomically-identified-stn-subterritories-in-parkinsons-disease/. Accessed May 18, 2025.« Back to 2016 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/electrophysiological-activity-of-anatomically-identified-stn-subterritories-in-parkinsons-disease/