gms | German Medical Science

Objective: Deep Brain Stimulation is an established treatment modality in various movement disorders. Targets are usually located within the basal ganglia. Due to the proximity of the target points to critical functional structures as the internal capsule, therapeutic yield might be limited by side effects. Furthermore energy consumption is potentially higher in conventional monopolar stimulation. Recently, segmented DBS leads have been made available. This technique comes with the promise of increased efficacy and side effect reduction. We therefore compared our preliminary data with segmented leads with the data from the Libra study conducted 4 years ago.

Methods: The purpose of the Libra study was to evaluate the effects of a new Deep Brain Stimulation System for reducing symptoms of advanced, Parkinson’s disease Also the Activities of Daily Living, UPDRS scores, Quality of life of subject, device parameters including active contact in relation to efficacy, frequency, type and severity of therapy related AE’s events were evaluated. 3 months data from patients with segmented leads (Infinity) 6 patients will be compared to the Libra data (6 patients).

Results: DBS Targeting was guided by three micro electrode recording tracts and a directional lead system (Infinity DBS, SJM) was implanted in an all-in-one GA setting in 6 patients. The segmented contacts were intensively tested at 90µs and 130 Hz in the postoperative course. Distinct effect/side-effect patterns for each contact were observed. Comparison of Parkinson’s symptoms as demonstrated by the UPDRS motor scores in the medication “off” state at Baseline compared to the medication “off” with stimulation “on” 3 months after device implantation. No differences in efficacy where seen between Libra and Infinity data among those 6 patients. However compared to the Libra data, no stimulation dependent side effects occurred in the Infinity group. Amplitude and frequency did not differ, however lower pulse width was used in 2 patients.

Conclusion: Segmented leads allowing current steering offer new perspectives for DBS and will likely result in increased treatment efficacy while reducing side effect at the same time. While this is true for DBS in general, there are cases with no good benefit/side-effect ratio could be achieved with conventional DBS. Since the threshold for side effects is higher in segmented leads, they are more adaptable to the individual patients’ needs and potentially resulting in a longer battery life.