A Bern-based research group working in the field of functional neurosurgery, led by Prof. Claudio Pollo and Dr. Andreas Nowacki, has succeeded in identifying the ideal stimulation site for treating essential tremor as part of an international study on deep brain stimulation.
Tremor and deep brain stimulation
Essential tremor is a disorder of the nervous system that manifests itself in severe rhythmic shaking and for which there is no known neurological cause. Deep brain stimulation, or DBS, is one of the most effective treatments for essential tremor. It is particularly indicated when patients do not respond adequately to drug therapy.
The trial
A total of five European centers participated in the interdisciplinary multicenter trial, including the university hospitals in Berlin, Amsterdam, Oxford, Cologne, and Bern. Clinical and imaging data from 119 patients were analyzed retrospectively. Given that deep brain stimulation is a relatively rare form of treatment, this represents the largest patient group recorded to date.
Results
Using patient data from magnetic resonance imaging (MRI) and computed tomography (CT) scans taken before and after deep brain stimulation, the electrode positions and the stimulated area in the brain were reconstructed and modeled, and then correlated with tremor reduction after 12 months. After statistical analysis of all data, an optimal stimulation site was identified at the transition zone between the motor thalamus and the subthalamic area. Using machine learning algorithms and cross-validation, a clinically relevant reduction in tremor of more than 50% was demonstrated for this «sweet spot». The results of this study were published in the journal Annals of Neurology.
Outlook
Based on the newly gained insights, surgical planning and postoperative stimulation settings will now be adjusted. The Bernese neurosurgeons hope that this will significantly improve and optimize deep brain stimulation in patients with tremors.
Original publication
Nowacki A, Barlatey S, Al-Fatly B, Dembek T, Bot M, Green AL, Kübler D, Lachenmayer ML, Debove I, Segura-Amil A, Horn A, Visser-Vandewalle V, Schuurman R, Barbe M, Aziz TZ, Kühn AA, Nguyen TAK, Pollo C. Probabilistic Mapping Reveals Optimal Stimulation Site in Essential Tremor. Ann Neurol. 2022 Feb 12.
