Voxel-based lesion symptom mapping analysis for dysphagia in stroke patients with isolated cerebellar lesions

Because the cerebellum plays a role in motor coordination, timing, sequencing, and feedback, it is hypothesized to be involved in swallowing-related functions. The role of the cerebellum in deglutition has become increasing evident, but the exact nature of this role remains inconclusive because of limited data from pure cerebellar lesions. Therefore, we conducted location analysis in isolated cerebellar lesions to complement previous findings and provide additional information. We reviewed 40 stroke patients with isolated cerebellar lesion. Lesion location and volume were measured on brain magnetic resonance images. We generated statistical maps of lesions related to VDS using voxel-based lesion symptom mapping (VLSM). We also created an overlay map of subgroups according to VDS score, those who have low risk and those who have high risk. Patients with cerebellar lesion had difficulty swallowing, both in the oral and pharyngeal phases. Multivariate analysis of cognitive function was selected as an independent predictor. In the group of high-risk patients, the overlay map showed some bilateral asymmetry, with a wider distribution in the left hemisphere and involvement of deep cerebellar nuclei. Using VLSM, we found that lesion location was associated with dysphagia. Although these results were not statistically significant, they showed a lesion pattern with predominant distribution in the left posterior lobe. Our results suggest that damage to the posterior lobe of the left cerebellum tends be related to severity of dysphagia in patients with isolated cerebellar lesion.