Microstimulation Is a Promising Approach in Achieving Better Lead Placement in Subthalamic Nucleus Deep Brain Stimulation Surgery.

Lin Shi,Jianguo Zhang,Shiying Fan,Tianshuo Yuan,Jie Zheng,Yu Diao,Huaying Fang,Anchao Yang,Guanyu Zhu,Hua Zhang,Huanguang Liu,Quan Zhang,Fangang Meng,Zunyu Xiao

doi:10.3389/fneur.2021.683532

Abstract

Background: The successful application of subthalamic nucleus (STN) deep brain stimulation (DBS) surgery relies mostly on optimal lead placement, whereas the major challenge is how to precisely localize STN. Microstimulation, which can induce differentiating inhibitory responses between STN and substantia nigra pars reticulata (SNr) near the ventral border of STN, has indicated a great potential of breaking through this barrier.Objective: This study aims to investigate the feasibility of localizing the boundary between STN and SNr (SSB) using microstimulation and promote better lead placement.Methods: We recorded neurophysiological data from 41 patients undergoing STN-DBS surgery with microstimulation in our hospital. Trajectories with typical STN signal were included. Microstimulation was applied near the bottom of STN to determine SSB, which was validated by the imaging reconstruction of DBS leads.Results: In most trajectories with microstimulation (84.4%), neuronal firing in STN could not be inhibited by microstimulation, whereas in SNr long inhibition was observed following microstimulation. The success rate of localizing SSB was significantly higher in trajectories with microstimulation than those without. Moreover, results from imaging reconstruction and intraoperative neurological assessments demonstrated better lead location and higher therapeutic effectiveness in trajectories with microstimulation and accurately identified SSB.Conclusion: Microstimulation on microelectrode recording is an effective approach to localize the SSB. Our data provide clinical evidence that microstimulation can be routinely employed to achieve better lead placement.

Highlights

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a well-accepted therapeutic approach for controlling the motor symptoms of Parkinson’s disease (PD) [1, 2]
Typical STN signal was recorded in 50 trajectories (62.5%) (Figure 4A)
In 56 trajectories (70.0%), putative substantia nigra pars reticulata (SNr) signal was identified at 1 mm above to 5 mm below the target, featured by a higher firing rate and a lower background compared to STN (Figure 4B)

Summary

Introduction

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a well-accepted therapeutic approach for controlling the motor symptoms of Parkinson’s disease (PD) [1, 2]. The major challenge of this optimal lead placement is how to precisely localize STN, especially the ventral boundary [6, 9] of STN that is an almond-shaped nucleus embedded deeply in between the diencephalon and the midbrain and surrounded by multiple brain structures. Due to insufficient imaging resolution and low signal-to-noise ratio [9, 11], conventional magnetic resonance imaging (MRI) strategies often fail in distinguishing STN from SNr. The successful application of subthalamic nucleus (STN) deep brain stimulation (DBS) surgery relies mostly on optimal lead placement, whereas the major challenge is how to precisely localize STN. Microstimulation, which can induce differentiating inhibitory responses between STN and substantia nigra pars reticulata (SNr) near the ventral border of STN, has indicated a great potential of breaking through this barrier

Methods

Results

Discussion

Conclusion