Sektionstage Frühjahr 2025 der Deutschen Gesellschaft für Neurochirurgie

Prof. Dr. med.

PD Dr. med.

Prof. Dr.

Hybrid Deep Brain Stimulation Conversion to Neurostimulator Capable of Precise Current Steering: Real-world Clinical Outcomes and Patient Experience

Innovationen

SFN02

Freie Themen

SFN04

Hybrid replacement procedures have been recently introduced1-4 and are offered to patients previously implanted with conventional single-source Deep Brain Stimulation (DBS) systems who experience limitations in clinical outcomes and/or device utilization. This technique uses an adapter to keep the existing DBS leads in place and connect them to a novel implantable pulse generator (IPG) with advanced programming capabilities including current fractionalization. We conducted a real-world evaluation of consecutive patients analyzing clinical outcomes and programming settings before and after the new IPG was implanted.This is a real-world, multicenter retrospective study including consecutive patients who were previously implanted with a conventional single-source DBS system who went on to convert to a new DBS IPG via an compatible adapter. In addition to clinical assessments, DBS parameters were documented, as well as the main motivation for the conversion procedure. All data were collected by site personnel per standard practice and without sponsor involvement.To date, twenty-three (23) consecutive patients (52% female) have been included in this ongoing study. They all underwent the implantation of new IPG devices at our university hospital. Previously implanted DBS leads were kept in place, and were located in the STN for patients with Parkinson"s Disease (n=14), in the GPi for dystonia patients (n=5) and in the Vim for patients with tremor (n=4). Clinical improvements were observed for more than half of the patients (n=12) compared to the pre-operative status. The other patients (n=10) sustained similar clinical outcomes. None of the patients had any worsening of their symptoms after the hybrid conversion procedure. In addition, some patients reported improvements in their experience with the new IPG (charging, size, battery longevity).Valuable benefits in clinical control and device management were noted in a significant proportion of patients who underwent a hybrid DBS conversion procedure. Hybrid conversion procedures are safe and can be clinically meaningful in patients previously implanted with single-source conventional DBS systems.

Sektion Funktionelle Neurochirurgie:

Abstractvortrag

Priv.-Doz. Dr.

Structural connectivity of the basal ganglia from patient-individual tractography for predicting therapeutic effects of deep brain stimulation in Parkinson"s Disease

Therapeutic approaches for Parkinson"s disease (PD) patients include deep brain stimulation (DBS) of the subthalamic nucleus (STN). However, the mechanisms underlying the therapeutic effects of STN-DBS are not completely understood. In this work, we investigate the patient-specific structural connectivity associated with DBS and its links to therapeutic effects.We applied tractography to reconstruct the white matter pathways of the brain in each individual patient. Imaging data were acquired from PD patients scheduled for STN-DBS at our centre (N = 69). Clinical assessments like the UPDRS questionnaire were acquired before and after DBS surgery. We first developed an optimised fibre tracking pipeline for tracking in the basal ganglia. Afterwards, we investigated the connectivity of the volume of tissue activated (VTA) to the cortex in general and correlated the derived connectivity with the clinical outcomes. Then, we specifically targeted the connectivity within the cortico-basal ganglia-thalamocortical loop for tractography and calculated a degree of modulation for each pathway, by taking the proportion of affected fibres by the VTA, and these were correlated with clinical outcome.VTA connectivity to the cortex revealed that VTA"s primarily connect to the SMA. Correlation analysis revealed a positive correlation between motor clinical outcome and VTA connection to the SMA, pre-motor, and motor cortices. Positive correlations between the degree of modulation of individual pathways and clinical outcomes were identified, with the strongest ones being for the connection between STN and primary motor cortex (Spearman"s rho = 0.55), STN and the primary sensory cortex (Spearman"s rho = 0.52), and STN and the supplementary motor area (Spearman"s rho = 0.34) pathwaysThis is, to the best of our knowledge, the largest study including patient-specific tractography of PD patients that underwent DBS to date. Taken together, the connectivity and pathway modulation profiles have the potential of building predictive clinical outcome models which could be used in a clinical context as a tool to guide therapy. The next steps will focus on validation using data from a partner centre, incorporation of non-motor symptoms into the analysis, and the development of symptom-specific predictive models.

Structural connectivity of the basal ganglia from patient-individual tractography for predicting therapeutic effects of deep brain stimulation in Parkinsons Disease

Prof.Dr.

Deep Brain Stimulation for Post-Stroke Movement Disorders: An Individual Participant Data (IPD) Meta-Analysis

Post-stroke movement disorders consisting of complex movement patterns with dystonia, chorea and tremor represent a therapeutical challenge. Under these circumstances, deep brain stimulation (DBS) should be considered as a potential effective treatment option, although it remains unclear, whether thalamic or pallidal DBS should be applied.We conducted an individual participant data (IPD) meta-analysis analyzing the efficacy of DBS of the globus pallidus internus (GPi), the ventral intermediate nucleus (VIM) or both (GPi+VIM) for the treatment of mixed movement disorders after stroke. PubMed, Embase and the Cochrane Library were searched for relevant articles. The Burke Fahn Marsden Dystonia Rating Scale (BFMRS)-motor and BFMRS-disability as well as the Fahn-Tolosa-Marín scale (FTM) for tremor were analyzed. In addition, correlation and regression analyses were performed to identify predictive markers (age, duration of disease, frequency, amplitude, intensity, and contact configuration).A total of eighteen studies consisting of 32 patients met the inclusion criteria. Both DBS of the GPi and VIM and combined (GPi+VIM) significantly improved the outcome scores for dystonia (BFMRS) and tremor (FTM), even on long-term follow-ups (>12 months). Most data published were found for the GPi. There were only a few studies reporting the effect of combined (GPi+VIM) stimulation. The effect of DBS was not related to age, contact configuration, stimulation intensity, frequency, amplitude, or disease duration. Adverse events (19 %) were temporarily and related to stimulation side effects.Our analysis indicates that DBS is effective in the treatment of post-stroke movement disorders with a low complication profile. Given the clinical improvement of both targets (GPi- and VIM-DBS), the authors advocate a combined DBS approach along with a trial stimulation. However, the study heterogeneity, reporting bias, and potential placebo effects of the published data may limit the quality of evidence in favor or against a target.

Lässt sich durch stereotaktisches Röntgen ein sweet spot zur Stimulation bei Tremor finden?

Viele Patienten mit Tremor leiden sehr unter ihren Symptomen. Die Patienten ziehen sich sozial zurück. Wenn die Medikamente nicht mehr helfen, ist die tiefe Hirnstimulation ein gute Behandlungsoption. Einige Patienten kommen sehr lange mit niedrigen Amplituden aus, während andere immer höhere Amplituden, um den Tremor zu unterdrücken. Mit der stereotaktischen Röntgenanlage kann die Lage der Elektroden im Vergleich zum geplanten Trajekt auf Millimeterniveau analysiert werden. Wir haben uns gefragt, ob die Patienten mit niedrigen Amplituden sich von der Elektrodenlage von den mit höheren Amplituden unterscheiden.52 Patient mit Tremor wurden bezüglich der geplanten und tatsächlichen Lage der Elektrode analysiert, nebst anatomischer Parameter, wie Breite des 3. Ventrikels, Länge der AC-PC Linie, der Pedunculi, dem Winkel zwischen den Pedunculi und der Stimulationsparameter.In der Analyse zeigt sich in durchschnittliche Abweichung von geplanter und realer Lage der Elektrode von x= -1,04 +/- 1,29mm, y= 1,07 +/-1,35mm, z= 0,63 +/- 2,07mm links und x= 0,7 +/- 1,91mm, y= 0,69 +/-1,84mm, z= 0,42 +/- 2,09mm rechts. Weder bei diesen Werten, noch bei den anderen analysierten Werten zeigen sich statistisch signifikante Auffälligkeiten.Ist es also egal, wo im Zielgebiet die Elektroden liegen? Wir glauben weiterhin, dass die Präzision bei der tiefen Hirnstimulation das Hauptziel der Implantation sein sollte. Bei der stereotaktischen Röntgenanlage ist der Vorteil, dass die Elektrodenposition nach der Fixierung unmittelbar überprüft und gegebenenfalls direkt korrigiert werden kann. Einen sweet spot für die Stimulation konnten wir leider nicht identifizieren.

Hörsaal West

FNCH 5

Sektion Funktionelle Neurochirurgie

FNCH 5
DBS

Appointment

Chairs

Programme

FNCH 5DBS

Appointment

Chairs

Programme

FNCH 5
DBS