Objective: Deep brain stimulation (DBS) targeting Globus pallidus pars interna (GPi) and subthalamic nucleus (STN) is an established surgical treatment for Parkinson’s disease (PD). Due to concerns about the effects of STN DBS on cognition, mood, and behavior, GPi DBS became a more attractive option. Due to the fact that the GPi is a much larger target (≈ 450 mm3) when compared to the STN (≈150 mm3) demands a higher charge density.

Background: With this research project, we hope to understand GPi DBS programming in patients with tremor-predominant and akinetic-rigid predominant PD and correlating with existing literature on GPi DBS programming in PD. The information gained from this research, will fasten the DBS programming session and it will decrease the time required to obtain appropriate settings, eventually will benefit in decreased battery usage and hence longer battery life.

Method: The study is open retrospective clinical observational case series and biologic registry design to evaluate the effects of GPi DBS in tremor and akinetic-rigidity predominant PD. 30 PD patients who underwent bilateral GPi DBS at University of Kentucky are included in the study. Target site in GPi nucleus is mapped to determine exact location of the tip of the lead. Electrode placement description will be in relation to anterior commissure-posterior commissure (AC-PC) line. The DBS settings parameters are noted at 6-month visit post-surgery. Contacts which are activated, and frequency chosen to control the symptoms are of particular interest.

Results: In tremor predominant patients, stimulation of the lower contacts were chosen in 60% of the individuals and average frequency of 180 Hz, pulse width of 110 microsec and voltage of 3.2v. In akinetic-rigid predominant PD patients, stimulation of the upper contacts were chosen in 70% of the individuals and average frequency of 180 Hz, pulse width of 80 microsec and voltage of 4v. The lead was placed in postero-inferior region of the globus pallidum in 90% of the patients.

Conclusion: Our findings are similar to the previously published literature, showing apparent functional difference between dorsal and ventral globus pallidum stimulation (1,2,3). The best electrode combination differ in tremor-predominant and akinetic-rigid predominant PD patients and understanding this might help to decrease the time required to obtain appropriate settings.

References: 1. Rajeev Kumar. Methods for Programming and Patient Management with Deep Brain Stimulation of the Globus Pallidus for the Treatment of Advanced Parkinson’s Disease and Dystonia. Movement Disorders. Vol. 17, Suppl. 3, 2002, pp. S198–S207. 2. Bejjani B, Damier P, Arnulf I, Bonnet AM, Vidailhet M, Dormont D, Pidoux B, Cornu P, Marsault C, Agid Y. Pallidal stimulation for Parkinson’s disease. Two targets? Neurology 1997;49:1564–1569. 3. 17. Krack P, Pollak P, Limousin P, Hoffmann D, Benazzouz A, Le Bas JF, Koudsie A, Benabid AL. Opposite motor effects of pallidal stimulation in Parkinson’s disease. Ann Neurol 1998;43:180–192.

« Back to 2019 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/dbs-programming-in-tremor-and-akinetic-rigid-predominant-parkinsons-disease/