Abstract
Introduction: The globus pallidus internus (GPi) region has evolved as a potential target for deep brain stimulation (DBS) in Parkinson’s disease (PD). DBS of the GPi (GPi DBS) is an established, safe and effective method for addressing many of the motor symptoms associated with advanced PD. It is important that clinicians fully understand this target when considering GPi DBS for individual patients. Methods: The literature on GPi DBS in PD has been comprehensively reviewed, including the anatomy, physiology and potential pitfalls that may be encountered during surgical targeting and post-operative management. Here, we review and address the implications of lead location on GPi DBS outcomes. Additionally, we provide a summary of randomized controlled clinical trials conducted on DBS in PD, together with expert commentary on potential applications of the GPi as target. Finally, we highlight future technologies that will likely impact GPi DBS, including closed-loop adaptive approaches (e.g. sensing-stimulating capabilities), advanced methods for image-based targeting and advances in DBS programming, including directional leads and pulse shaping. Results: There are important disease characteristics and factors to consider prior to selecting the GPi as the DBS target of PD surgery. Prior to and during implantation of the leads it is critical to consider the neuroanatomy, which can be defined through the combination of image-based targeting and intraoperative microelectrode recording strategies. There is an increasing body of literature on GPi DBS in patients with PD suggesting both short- and long-term benefits. Understanding the GPi target can be useful in choosing between the subthalamic (STN), GPi and ventralis intermedius nucleus as lead locations to address the motor symptoms and complications of PD. Conclusion: GPi DBS can be effectively used in select cases of PD. As the ongoing DBS target debate continues (GPi vs. STN as DBS target), clinicians should keep in mind that GPi DBS has been shown to be an effective treatment strategy for a variety of symptoms, including bradykinesia, rigidity and tremor control. GPi DBS also has an important, direct anti-dyskinetic effect. GPi DBS is easier to program in the outpatient setting and will allow for more flexibility in medication adjustments (e.g. levodopa). Emerging technologies, including GPi closed-loop systems, advanced tractography-based targeting and enhanced programming strategies, will likely be future areas of GPi DBS expansion. We conclude that although the GPi as DBS target may not be appropriate for all PD patients, it has specific clinical advantages.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 7-30 |
| Number of pages | 24 |
| Journal | Neurology and Therapy |
| Volume | 10 |
| Issue number | 1 |
| DOIs |
|
| State | Published - Jun 2021 |
| Externally published | Yes |
Bibliographical note
Funding Information:Ka Loong Kelvin Au, Takashi Tsuboi, Robert S Eisinger, Kathryn Moore, Janine Lemos Melo Lobo Jofili Lopes, Marshall T Holland, Zhongxing Peng-Chen and Addie Patterson declare that they have no conflict of interest. Joshua K Wong’s research is supported by NIH grant 1R25NS108939. Vanessa M Holanda has served as consultant for Abbott, Boston Scientific, Gusmed (Epimed affiliated) and Medicicor (Medtronic affiliated). Kelly Foote has received occasional consulting fees from Medtronic and Boston Scientific. His research is primarily funded by NIH and multiple foundation sources. Implantable devices for Dr. Foote's DBS-related research have been provided by Medtronic and Neuropace. Dr. Foote has participated as a site-implanting surgeon in multicenter DBS-related research studies sponsored by Abbott/St. Jude, Boston Scientific, and Functional Neuromodulation. The University of Florida receives partial funding for Dr. Foote's functional neurosurgery fellowship from Medtronic. Adolfo Ramirez-Zamora has received support from the Parkinson's Foundation and consulting honoraria from Boston Scientific, Medtronic, Stealth, Rho, CNS Raters and Bracket INC in the past 24 months. Michael S Okun serves as a consultant for the Parkinson’s Foundation, and has received research grants from NIH, Parkinson’s Foundation, the Michael J. Fox Foundation, the Parkinson Alliance, Smallwood Foundation, the Bachmann-Strauss Foundation, the Tourette Syndrome Association, and the UF Foundation. Dr. Okun’s DBS research is supported by: NIH grants R01 NR014852 and R01NS096008. Dr. Okun is PI of the NIH R25NS108939 Training Grant. Dr. Okun has received royalties for publications with Demos, Manson, Amazon, Smashwords, Books4Patients, Perseus, Robert Rose, Oxford and Cambridge (movement disorders books). Dr. Okun is an associate editor for New England Journal of Medicine Journal Watch Neurology. Dr. Okun has participated in Continuing Medical Education and educational activities on movement disorders sponsored by the Academy for Healthcare Learning, PeerView, Prime, QuantiaMD, WebMD/Medscape, Medicus, MedNet, Einstein, MedNet, Henry Stewart, American Academy of Neurology, Movement Disorders Society and Vanderbilt University. The institution and not Dr. Okun receives grants from Medtronic, Abbvie, Boston Scientific, Abbott and Allergan and the PI has no financial interest in these grants. Dr. Okun has participated as a site PI and/or co-PI for several NIH-, foundation- and industry-sponsored trials over the years but has not received honoraria. Research projects at the University of Florida receive device and drug donations. Leonardo Almeida has served as an educational consultant and has participated in advisory boards for Medtronic and Boston Scientific, and has received honoraria for his services.
Publisher Copyright:
© 2020, The Author(s).
Keywords
- DBS
- Deep brain stimulation
- Globus pallidus internus
- GPi
- Neuromodulation
- Outcomes
- Parkinson’s disease
- STN
- Subthalamic nucleus
- Targeting