Qingyang Yu,1,2 Yuanyuan Cui,1 Shuwen Dong,1 Yanqing Ma,1 Yi Xiao,1 Li Fan,1 Shiyuan Liu1 

1Department of Radiology, Changzheng Hospital, Navy Military Medical University, Shanghai, 200003, People’s Republic of China; 2Department of Neurosurgery, Changhai Hospital, Navy Military Medical University, Shanghai, 200433, People’s Republic of China

Correspondence: Shiyuan Liu, Department of Radiology, Changzheng Hospital, Navy Military Medical University, 415 Fengyang Road, Shanghai, 200003, People’s Republic of China, Fax +86 2181886012, Email radiology_cz@163.com

Objective: Hemifacial spasm (HFS) is a clinical neurosurgical disease, which brain structural alterations caused by HFS remain a topic of debate. We evaluated changes in brain microstructure associated with HFS and observed their relevance to clinical characteristics.
Methods: We enrolled 72 participants. T1-weighted structural and diffusion tensor images were collected from all participants using 3.0T magnetic resonance equipment. Voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) were used to identify changes in gray matter volume (GMV) and disruptions in white matter (WM) integrity. The severity of the spasms was graded using the Cohn scale.
Results: VBM analysis revealed that the GMV was significantly reduced in the left Thalamus and increased GMV in the right Cerebellum IV-V of the HFS group. TBSS analysis showed that FA in the left superior longitudinal fasciculus (SLF) of the HFS group was significantly increased. GMV in the thalamus showed a negative correlation with disease duration and Cohn grade, while FA in the left SLF had a positive correlation with both the disease duration and Cohn grade.
Conclusion: We identified regions with altered GMV in HFS patients. Additionally, we determined that FA in the left SLF might serve as a significant neural indicator of HFS.

Keywords: hemifacial spasm, voxel-based morphometry, diffusion tensor imaging, tract-based spatial statistics, Cohn grading