Prospective evaluation of determining the most effective contact for tremor control in patients with deep brain stimulation based on individual tractography (TremTract Study)
Final Report Abstract
The objective of this project was to prospectively test the hypothesis whether imaging-guided contact selection for tremor control by deep brain stimulation (DBS) based on standardized individual tractography of the dentato-rubro-thalamic tract (DRTT) is non-inferior to clinical contact selection in patients with Parkinson’s Disease (PD) and Essential Tremor (ET). Imaging-guided strategies for DBS programming provide the chance of reducing programming time and complexity. To date, there are no evidence-based paradigms to specifically address tremor in ET and PD. Converging research points to an involvement of cerebello-thalamocortical networks in tremor pathophysiology across diseases. Preliminary evidence suggests that the overlap of the DBS stimulation spread and the DRTT, on of the major pathways of this network, could serve as a marker for the tremor-suppressing DBS effect. To prospectively test this hypothesis, tremor control by DBS was evaluated by monopolar clinical testing in 16 ET patients (i.e. 28 hemispheres with clinically relevant contralateral tremor) and 24 PD patients (i.e. 29 hemispheres with clinically relevant contralateral tremor) with directional DBS leads in the ventral intermediate nucleus of the thalamus/posterior subthalamic area (VIM/PSA) in ET or subthalamic nucleus (STN) in PD. The primary outcome was percentage tremor suppression (rest, kinetic, postural) objectively assessed by an accelerometry-based tremor score. The effect of the clinically most effective contact was compared to the effect of the contact with the highest overlap of the stimulation spread and the DRTT, determined via individual tractography, assuming a non-inferiority margin of ≤ 20%. Tremor control by stimulation via the imaging-based selected contact was non-inferior to the clinically chosen contact for both ET (median difference best clinical vs. best imaging-based contact -8%, 95% CI -11.5% to -3.5%) and PD (median difference -10%, 95% CI -20% to -4%). Linear-mixed effect models revealed a consistent association between tremor control and the DRTT overlap across target points and diseases. This study provides evidence that the overlap of the stimulation spread with the individual DRTT is a suitable marker for imaging-guided DBS programming for Parkinsonian tremor in STN-DBS and ET in VIM/PSA-DBS. In a next step, these results need to be validated in longterm cross-over studies.
Publications
-
Accelerometric Classification of Resting and Postural Tremor Amplitude. Sensors, 23(20), 8621.
van der Linden, Christina; Berger, Thea; Brandt, Gregor A.; Strelow, Joshua N.; Jergas, Hannah; Baldermann, Juan Carlos; Visser-Vandewalle, Veerle; Fink, Gereon R.; Barbe, Michael T.; Petry-Schmelzer, Jan Niklas & Dembek, Till A.
