Session Information
Date: Wednesday, September 25, 2019
Session Title: Surgical Therapy
Session Time: 1:15pm-2:45pm
Location: Les Muses Terrace, Level 3
Objective: To examine the differential effects of subthalamic nucleus deep brain stimulation (STN DBS) amplitude (high and low) and lead laterality (Left-Right-bilateral) on speech intelligibility and motor symptoms in patients with Parkinson´s disease (PD).
Background: STN DBS is performed to control motor symptoms of PD. However, decreased speech intelligibility is a frequent side effect, limiting the extent to which other symptoms can be suppressed by DBS. The exact cause of post-DBS dysarthria is unknown. Electrical stimulation parameters and lead position have been implicated in speech outcome.
Method: Nine patients with PD (5 males, age 57.6±6.3years, 14±6.6years disease duration) participated in this study at 2.4 ±1.7years after DBS surgery. Speech was recorded without medication in 6 conditions for each participant: with Left side stimulation-on at high amplitude (4V) and at low amplitude (2V); Right side stimulation on at 4V and at 2V; bilateral stimulation at 4V and at 2V. Speech intelligibility (% of words understood) and UPDRS-III were rated in a blinded way.
Results: There was a significant effect of laterality and amplitude on UPDRS-III scores, with bilateral stimulation at high amplitude being most effective. Speech was significantly better when patients were stimulated at low amplitude on the Left STN (83% ± 17) compared to high amplitude on the same side of the brain (69%, ± 27, p<.05). However, patients had better speech when stimulated bilaterally at low amplitude (85% ± 12, p<.01) than unilaterally at high. There was a significant negative correlation between motor and speech scores when patients were stimulated bilaterally at high amplitude.
Conclusion: In this small number of patients our data confirm the hypothesis that speech is modulated at lower thresholds than motor symptoms. There is no conclusive data for the preponderance of the left STN on motor speech control.
To cite this abstract in AMA style:
E. Tripoliti, B. Veggia, M. Hariz, P. Limousin. Differential effects of stimulation amplitude and lead laterality of deep brain stimulation of the subthalamic nucleus on speech and Parkinsonian motor symptoms [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/differential-effects-of-stimulation-amplitude-and-lead-laterality-of-deep-brain-stimulation-of-the-subthalamic-nucleus-on-speech-and-parkinsonian-motor-symptoms/. Accessed June 15, 2025.« Back to 2019 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/differential-effects-of-stimulation-amplitude-and-lead-laterality-of-deep-brain-stimulation-of-the-subthalamic-nucleus-on-speech-and-parkinsonian-motor-symptoms/