# Effects of STN-DBS treatment on voice characteristics in patients with Parkinson's Disease

## TL;DR

This study shows that STN-DBS improves voice characteristics in Parkinson's patients early after surgery, with specific brain stimulation areas linked to better outcomes.

## Contribution

The study identifies a negative correlation between DSI improvement and VTA overlap in the left limbic STN after STN-DBS.

## Key findings

- Subjective VHI scores improved significantly at 3 months post-STN-DBS but not at 6 months.
- Voice parameters like DSI, Jitter, and Shimmer improved significantly at 3 and 6 months post-surgery.
- DSI improvement rate was negatively correlated with VTA overlap in the left limbic STN at 6 months.

## Abstract

To evaluate the early changes of voice characteristics after deep brain stimulation (DBS) of subthalamic nucleus (STN) in patients with Parkinson's disease (PD) and to investigate the effect of the volume of tissue activated (VTA) of the STN on voice.

From April 2024 to October 2024, 23 Parkinson's disease patients who underwent deep brain stimulation of subthalamic nucleus in Tianjin Huanhu Hospital and 22 healthy volunteers were collected. The voice characteristics of 23 Parkinson's disease patients without medication were evaluated preoperative, 3 months and 6 months after surgery. The voice handicap index (VHI) scale was used to evaluate the subjective voice function of patients. LingWAVES voice analysis software was used to collect patient and healthy control data and perform voice acoustic analysis. We further analyzed the correlation between postoperative tissue activation volume and voice characteristics.

The subjective VHI scores improved significantly at 3 months postoperatively (p = 0.025), but there was no significant difference at 6 months postoperatively (p = 0.283). The parameters including dysphonia severity index (DSI), fundamental frequency perturbation (Jitter) and amplitude perturbation (Shimmer) were significantly improved three and six months postoperatively compared with baseline (p < 0.05). There was a negative correlation between the improvement rate of DSI and the VTA overlap within limbic STN in the left hemisphere six months postoperatively (R2 = 0.4413, p < 0.001).

STN-DBS can improve the voice characteristics of Parkinson's disease patients in the early stage after surgery, the improvement rate of DSI was negatively correlated with the VTA overlap within limbic STN in the left hemisphere.