Session Information
Date: Monday, June 5, 2017
Session Title: Surgical Therapy: Parkinson’s Disease
Session Time: 1:45pm-3:15pm
Location: Exhibit Hall C
Objective: The aim of this study is to define a simple clinical benchmark parameter for assessing the quality of STN-DBS outcome in PD.
Background: Despite being a well-established treatment option in PD, STN-DBS shows a significant individual outcome variability. This includes patient/disease related factors, variable responsiveness of different PD symptoms to DBS, as well as differences in lead placement and clinical DBS programming. The levodopa response correlates significantly with the DBS stimulation response and is therefore used as a DBS eligibility criterion. Here we propose to use a ratio between best levodopa response and DBS response as a benchmark for individual DBS outcome quality.
Methods: We reevaluated 15 PD patients with STN DBS (Øage 63,1years, ØUPDRS III(off): 49,8) 6-60 months after implantation. Motor symptoms control (reduction in UPDRS III) by STN-DBS and Levodopa challenge were assessed after an overnight medication (+1h stim off) washout. When DBS implantation was <12 months we used the preoperative Levodopa challenge. The DBS response ratio (DBSrr) was defined as stimulation effect / levodopa response. Patients were categorized into two groups (good/suboptimal) based on a threshold of <0,7. Additionally, active contact (aC) location within the different STN subsegments was determined by fusing postoperative CT with preoperative MRI and Yelnick atlas (1) registration using Suretune® (Medtronic Sapiens, NL).
Results: 6 suboptimal responders (median DBSrr: 0,50) had only 5/12 aC placed within the sensorimotor segment of the STN, 4 aC were in the limbic subpart and 3 outside of the STN. An aC location outside of the sensorimotor STN unilaterally was found in 3/6 subjects (median DBSrr: 0,56) and bilaterally in 3/6 subjects (median DBSrr: 0,57). In 9 good responders (median DBSrr: 1,02) 18/18 aC were located within the sensorimotor segment of the STN. Lead revision after failed reprogramming attempts was indicated in all 6 patients.
Conclusions: STN-DBS is a effective treatment for PD on a group level, but there is an increasing concern about DBS “failures”, in whom postoperative outcomes do not match the preoperative expectations. An excellent motor-on after a levodopa challenge is the best predictor of DBS outcome. Here, we have used the ratio between stimulation and levodopa response to eliminate patient and disease related factors of outcome variability and to create an individual benchmark for the DBS outcome.
References: 1. A three-dimensional, histological and deformable atlas of the human basal ganglia. I. Atlas construction based on immunohistochemical and MRI data.
Yelnik J1, Bardinet E, Dormont D, Malandain G, Ourselin S, Tandé D, Karachi C, Ayache N, Cornu P, Agid Y.
Neuroimage. 2007 Jan 15;34(2):618-38. Epub 2006 Nov 15.
To cite this abstract in AMA style:
L. Lange, M. Reich, R. Nickl, F. Steigerwald, C. Matthies, J. Volkmann. The DBS response ratio: An individual benchmark parameter of DBS quality [abstract]. Mov Disord. 2017; 32 (suppl 2). https://www.mdsabstracts.org/abstract/the-dbs-response-ratio-an-individual-benchmark-parameter-of-dbs-quality/. Accessed June 14, 2025.« Back to 2017 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/the-dbs-response-ratio-an-individual-benchmark-parameter-of-dbs-quality/