Structural and Functional Amygdala Abnormalities in Hemifacial Spasm

Conclusions: This is the first study to show structural and functional brain abnormalities in HFS. The volumetric and rsFC amygdala abnormalities were potentially driven by HFS, providing novel insights into HFS pathophysiology. Introduction Hemifacial spasm (HFS) is a neuromuscular movement disorder characterized by unilateral, involuntary, and paroxysmal contractions of the muscles innervated by the facial nerve (1, 2). The spasm usually originates from the orbicularis oculi muscle of the eyelid, and as the disease progresses, spasms spread to the orbicularis oris and buccinator muscles (1, 3). Even though HFS is not a life-threatening condition, it inevitably causes various degrees of visual and verbal disabilities, which can be distressing and lead to social phobia (4). It is widely considered that HFS is caused by vascular contact to the facial nerve in the cerebellopontine angle cistern (5, 6); however, to date, only two studies have evaluated gray matter abnormalities in HFS patients. The first study by Bao et al. (7) found that patients with HFS showed reduced gray matter volume (GMV) in the thalamus, putamen, pallidum, amygdala, and parahippocampal gyrus compared to healthy volunteers. The second study, however, found that HFS patients had decreased GMV in the right inferior parietal lobule and increased GMV in the cerebellar lobule compared to controls (8). It should be noted that both studies employed voxel-based morphometry (VBM) to investigate GMV abnorm...
Source: Frontiers in Neurology - Category: Neurology Source Type: research