Brain Stimulation for Parkinson's Disease

May 9
4 min read

Updated: May 21

Dr. Prem Pillay, Singapore

Senior Consultant Neurosurgeon with super specialty training in Neurosurgical Oncology

(Fellow at MD Anderson Cancer Center and Hospital, U of Texas, USA)

Selection Criteria

Deep brain stimulation (DBS) has become a standard treatment for advanced Parkinson’s disease (PD), but selecting the right candidates is crucial for optimal outcomes. Traditional selection criteria, such as those outlined in the Core Assessment Program for Surgical Interventional Therapies in Parkinson’s Disease (CAPSIT-PD), are considered outdated due to advances in understanding PD’s heterogeneity. Current practices emphasize a comprehensive assessment of both motor and non-motor symptoms, including genetic and phenotypic characterisation, to better predict surgical outcomes. An interdisciplinary team often reviews potential candidates to evaluate the risk-benefit profile, ensuring realistic expectations are set7. Currently too few patients are receiving DBS globally states Dr Prem Pillay because of the lack of trained Neuro Specialists, Equipment costs and availability,and patient access to specialized Neuro Centers.

Targets

The subthalamic nucleus (STN) and globus pallidus internus (GPi) are the primary targets for DBS in PD. Both targets have shown similar efficacy in improving motor symptoms, but they differ in their impact on medication reduction and mood. STN DBS allows for a greater reduction in dopaminergic medication but may negatively affect speech and mood, whereas GPi DBS is associated with better mood outcomes. Emerging targets, such as the pedunculopontine nucleus and the caudal zona incerta, show promise for addressing specific symptoms like axial symptoms and tremor.

Methods and Techniques

The DBS procedure involves precise localization of the target area, often using ventriculography and/or high definition MRI (Magnetic Resonance Imaging ) and intraoperative neuronal microrecording to ensure accurate placement. In leading Neuro centers for example, DBS is typically performed bilaterally in a single session with awake anesthesia, using frame-based techniques and microelectrode recordings for final lead positioning. Advances in neuroimaging are expected to further refine targeting accuracy.

Results

DBS has been shown to significantly improve motor function and quality of life in PD patients, with benefits sustained even in advanced stages of the disease. A meta-analysis of randomized controlled trials indicates that both STN and GPi DBS provide similar motor benefits, although STN DBS allows for a greater reduction in medication. However, axial symptoms such as speech and balance may not improve as much and can sometimes worsen post-surgery.

Future Innovations of Brain Stimulation of Parkinson's Disease

The future of DBS in PD includes the development of adaptive DBS systems, such as closed-loop approaches that adjust stimulation in real-time based on patient needs. New hardware with directional stimulation capabilities and advanced imaging techniques are being explored to enhance precision and efficacy. Research is also focused on identifying new brain targets and refining programming strategies to address treatment-resistant symptoms.

Conclusion

Deep brain stimulation remains a highly effective treatment for Parkinson’s disease, with ongoing innovations aimed at improving patient outcomes. Careful patient selection, precise targeting, and advanced programming are essential for maximizing the benefits of DBS. Dr Prem Pillay explains that future advancements in technology and methodology hold promise for further enhancing the efficacy and scope of this treatment. Apart from Parkinsons disease , patients with morbid obesity, treatment resistant depression and other functional conditions may benefit from the techniques and technologies used for Parkinsons disease in the near future.