TY - JOUR A1 - Kremer, Naomi I. A1 - Pauwels, Rik W. J. A1 - Pozzi, Nicolò G. A1 - Lange, Florian A1 - Roothans, Jonas A1 - Volkmann, Jens A1 - Reich, Martin M. T1 - Deep Brain Stimulation for Tremor: Update on Long-Term Outcomes, Target Considerations and Future Directions JF - Journal of Clinical Medicine N2 - Deep brain stimulation (DBS) of the thalamic ventral intermediate nucleus is one of the main advanced neurosurgical treatments for drug-resistant tremor. However, not every patient may be eligible for this procedure. Nowadays, various other functional neurosurgical procedures are available. In particular cases, radiofrequency thalamotomy, focused ultrasound and radiosurgery are proven alternatives to DBS. Besides, other DBS targets, such as the posterior subthalamic area (PSA) or the dentato-rubro-thalamic tract (DRT), may be appraised as well. In this review, the clinical characteristics and pathophysiology of tremor syndromes, as well as long-term outcomes of DBS in different targets, will be summarized. The effectiveness and safety of lesioning procedures will be discussed, and an evidence-based clinical treatment approach for patients with drug-resistant tremor will be presented. Lastly, the future directions in the treatment of severe tremor syndromes will be elaborated. KW - deep brain stimulation KW - tremor KW - essential tremor KW - Parkinson’s disease KW - outcomes KW - clinical approach KW - target considerations KW - future directions Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244982 SN - 2077-0383 VL - 10 IS - 16 ER - TY - JOUR A1 - Gonzalez‐Escamilla, Gabriel A1 - Muthuraman, Muthuraman A1 - Reich, Martin M. A1 - Koirala, Nabin A1 - Riedel, Christian A1 - Glaser, Martin A1 - Lange, Florian A1 - Deuschl, Günther A1 - Volkmann, Jens A1 - Groppa, Sergiu T1 - Cortical network fingerprints predict deep brain stimulation outcome in dystonia JF - Movement Disorders N2 - Background Deep brain stimulation (DBS) is an effective evidence‐based therapy for dystonia. However, no unequivocal predictors of therapy responses exist. We investigated whether patients optimally responding to DBS present distinct brain network organization and structural patterns. Methods From a German multicenter cohort of 82 dystonia patients with segmental and generalized dystonia who received DBS implantation in the globus pallidus internus, we classified patients based on the clinical response 3 years after DBS. Patients were assigned to the superior‐outcome group or moderate‐outcome group, depending on whether they had above or below 70% motor improvement, respectively. Fifty‐one patients met MRI‐quality and treatment response requirements (mean age, 51.3 ± 13.2 years; 25 female) and were included in further analysis. From preoperative MRI we assessed cortical thickness and structural covariance, which were then fed into network analysis using graph theory. We designed a support vector machine to classify subjects for the clinical response based on individual gray‐matter fingerprints. Results The moderate‐outcome group showed cortical atrophy mainly in the sensorimotor and visuomotor areas and disturbed network topology in these regions. The structural integrity of the cortical mantle explained about 45% of the DBS stimulation amplitude for optimal response in individual subjects. Classification analyses achieved up to 88% of accuracy using individual gray‐matter atrophy patterns to predict DBS outcomes. Conclusions The analysis of cortical integrity, informed by group‐level network properties, could be developed into independent predictors to identify dystonia patients who benefit from DBS. KW - brain networks KW - clinical outcome KW - deep brain stimulation KW - dystonia Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-213532 VL - 34 IS - 10 SP - 1536 EP - 1545 ER - TY - JOUR A1 - Pasos, Uri E. Ramirez A1 - Steigerwald, Frank A1 - Reich, Martin M. A1 - Matthies, Cordula A1 - Volkmann, Jens A1 - Reese, René T1 - Levodopa modulates functional connectivity in the upper beta band between bubthalamic nucleus and muscle activity in tonic and phasic motor activity patterns in Parkinson’s disease JF - Frontiers in Human Neuroscience N2 - Introduction: Striatal dopamine depletion disrupts basal ganglia function and causes Parkinson’s disease (PD). The pathophysiology of the dopamine-dependent relationship between basal ganglia signaling and motor control, however, is not fully understood. We obtained simultaneous recordings of local field potentials (LFPs) from the subthalamic nucleus (STN) and electromyograms (EMGs) in patients with PD to investigate the impact of dopaminergic state and movement on long-range beta functional connectivity between basal ganglia and lower motor neurons. Methods: Eight PD patients were investigated 3 months after implantation of a deep brain stimulation (DBS)-system capable of recording LFPs via chronically-implanted leads (Medtronic, ACTIVA PC+S®). We analyzed STN spectral power and its coherence with EMG in the context of two different movement paradigms (tonic wrist extension vs. alternating wrist extension and flexion) and the effect of levodopa (L-Dopa) intake using an unbiased data-driven approach to determine regions of interest (ROI). Results: Two ROIs capturing prominent coherence within a grand average coherogram were identified. A trend of a dopamine effect was observed for the first ROI (50–150 ms after movement start) with higher STN-EMG coherence in medicated patients. Concerning the second ROI (300–500 ms after movement start), an interaction effect of L-Dopa medication and movement task was observed with higher coherence in the isometric contraction task compared to alternating movements in the medication ON state, a pattern which was reversed in L-Dopa OFF. Discussion: L-Dopa medication may normalize functional connectivity between remote structures of the motor system with increased upper beta coherence reflecting a physiological restriction of the amount of information conveyed between remote structures. This may be necessary to maintain simple movements like isometric contraction. Our study adds dynamic properties to the complex interplay between STN spectral beta power and the nucleus’ functional connectivity to remote structures of the motor system as a function of movement and dopaminergic state. This may help to identify markers of neuronal activity relevant for more individualized programming of DBS therapy. KW - Parkinson’s disease KW - subthalamic nucleus KW - deep brain stimulation KW - local field potentials KW - dopamine KW - movement Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201540 VL - 13 IS - 223 ER -