Lateral medullary syndrome following injury of the vestibular pathway to the core vestibular cortex: Diffusion tensor...

The parieto-insular vestibular cortex (PIVC) is a core region of vestibular input into regions of the cortex. The vestibular nuclei have reciprocal connections with the PIVC. However, little is known about injury of the core vestibular pathway to the PIVC in patients with dorsolateral medullary infarctions. In this study, using diffusion tensor tractography (DTT), we investigated injury of the neural connections between the vestibular nuclei and the PIVC in patients with typical central vestibular disorder.

Eight consecutive patients with lateral medullary syndrome and 10 control subjects were recruited for this study. To reconstruct the core vestibular pathway to the PIVC, we defined the seed region of interest (ROI) as the vestibular nuclei of the pons and the target ROI as the PIVC. Fractional anisotropy (FA), mean diffusivity (MD), and tract volume were measured.

The core vestibular pathway to the PIVC showed significantly lower tract volume in patients compared with the control group (p<0.05). By contrast, other DTI parameters did not show significant differences between the patient and control groups (p>0.05).

In conclusion, injury of the core vestibular pathway to the PIVC was demonstrated in patients with lateral vestibular syndrome following dorsolateral medullary infarcts. We believe that analysis of the core vestibular pathway to the PIVC using DTT would be helpful in evaluating patients with lateral medullary syndrome.