Glymphatic system-dependent mechanisms connecting sudden sensorineural hearing loss to cognitive and emotional impairments

Sudden sensorineural hearing loss (SSNHL) is considered a potential risk factor for cognitive and emotional disorders. Numerous studies have highlighted the function of glymphatic system associated with cognition and emotion, but the underlying neural mechanisms linking SSNHL and cognitive-emotional impairments remain unclear. To further investigate, a total of 60 patients with SSNHL and 60 healthy volunteers were recruited for this study. We calculated volumes of the choroid plexus (ChP), enlarged perivascular spaces (EPVS) and four brain ventricles, including the bilateral lateral ventricles, the third ventricle, and the fourth ventricle, using convolutional neural network model and Freesurfer automatic segmentation tool. The volumes of the ChP and EPVS were used to assess the function of glymphatic system. Subsequently, volumetric differences between groups and the relationship between the volumes of the ChP, EPVS and four brain ventricles were analyzed. Moreover, we explored the correlation between MRI characteristics and neuropsychological scale scores in SSNHL patients. Compared with healthy volunteers, SSNHL patients presented larger ChP and EPVS volumes. In addition, the ChP volume showed a significant correlation with the severity of cognitive and emotional deficits in patients with SSNHL. Taken together, our results suggest alterations in MRI markers associated with glymphatic function in SSNHL patients. Differences in the ChP and EPVS volumes among the groups, with the enlarged ChP volume associated with cognitive and emotional disorders in patients, suggest that volumetric alterations in the ChP and EPVS may serve as characteristic measures in SSNHL.