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Journal of Neurorestoratology  2020, Vol. 8 Issue (3): 160-171    doi: 10.26599/JNR.2020.9040016
Research Article     
The clinical effect of vagus nerve stimulation in the treatment of patients with a minimally conscious state
Xun-Jie Xiang(✉), Liu-Zhong Sun, Cai-Bang Xu, Yong Xie, Ming-Yan Pan, Jiang Ran, Yang Hu, Bang-Xie Nong, Qu Shen, Hua Huang, Sheng-Hui Huang, Yan-Zhong Yu
Neurosurgery Department, Guangxi Jiangbin Hospital, Nanning 530021, Guangxi, China
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Abstract  Objective:

Vagus nerve stimulation (VNS) has recently been used in neurorehabilitation and the recovery of consciousness based on its effects on cortical plasticity. The aim of this study was to examine the therapeutic effects of VNS on patients with a minimally conscious state (MCS).


All patients included in the study were assessed more than 5 months after injury and were receiving regular rehabilitation at our hospital from August 2018 to October 2019. Ten patients diagnosed with MCS by Coma Recovery Scale-Revised (CRS-R) test who underwent VNS surgery were enrolled. The scores on CRS-R evaluation at baseline (before VNS implantation) and 1, 3, and 6 months after VNS treatment were recorded. The stimulation parameters were chosen according to a previous study. All clinical rehabilitation protocols remained unchanged during the study. Furthermore, safety was assessed by analyzing treatment-emergent adverse events (TEAEs).


No significant improvement in the total CRS-R scores at the end of the 1-month follow-up was observed (p > 0.05). After 3 months of stimulation, a significant difference (p = 0.0078) was observed in the total CRS-R scores compared with the baseline. After 6 months of VNS treatment, CRS-R assessments showed a continuous significant improvement (p = 0.0039); one patient emerged from the MCS and recovered functional communication and object use. Interestingly, one item of CRS-R scores on visual domain was sensitive to VNS treatment (p = 0.0039). Furthermore, no serious adverse event occurred throughout the study.


This exploratory study provides preliminary evidence suggesting that VNS is a safe and effective tool for consciousness recovery in patients with MCS.

Key wordsdisorders of consciousness      vegetative state      minimally conscious state      vagus nerve stimulation     
Received: 24 May 2020      Published: 14 September 2020
Corresponding Authors: Xun-Jie Xiang   
Cite this article:

Xun-Jie Xiang, Liu-Zhong Sun, Cai-Bang Xu, Yong Xie, Ming-Yan Pan, Jiang Ran, Yang Hu, Bang-Xie Nong, Qu Shen, Hua Huang, Sheng-Hui Huang, Yan-Zhong Yu. The clinical effect of vagus nerve stimulation in the treatment of patients with a minimally conscious state. Journal of Neurorestoratology, 2020, 8: 160-171.

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CaseSexAge (years)CausesCourse (months)
1Male24Traumatic brain injury6
2Female61Traumatic brain injury10
3Female66Cerebral infarction, hemorrhage after thrombolysis5
4Male19Traumatic brain injury6
5Female55Cerebral hemorrhage7
6Female47Traumatic brain injury6.5
7Male51Cerebral hemorrhage8
8Female39Cerebral hemorrhage5
9Male48Cerebral hemorrhage6.6
10Male29Hypoxic-ischemic encephalopathy11.5
Table 1Clinical information of MCS patients.
1 month3 months6 months
Table 2The total CRS-R scores of MCS patients at baseline and 1 month, 3 months , 6 months after VNS.
1M vs. baseline3M vs. baseline6M vs. baseline1M vs.3M1M vs. 6M3M vs. 6M
Total CRS-R score> 0.050.00780.00390.01560.0078> 0.05
Auditory function/> 0.05> 0.05> 0.05> 0.05> 0.05
Visual function> 0.050.01560.00780.03130.0156> 0.05
Motor function/> 0.05> 0.05> 0.05> 0.05> 0.05
Oromotor/verbal function> 0.05> 0.05> 0.05> 0.05> 0.05> 0.05
Communication//> 0.05///
Arousal> 0.05> 0.05> 0.05> 0.05> 0.05/
Table 3Statistical analysis (p-value) of behavioral assessment by CRS-R test.
Case Auditory function scale Visual function scale Motor function scale Oromotor/verbal function scale Communication scale Arousal scale
Table 4The specific CRS-R subscales of each patient during follow-up.
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