Cortical-Basal Ganglia-Cerebellar Networks in Unilateral Vocal Fold Paralysis: A Pilot Study.

Objectives/hypothesis: To evaluate differences in cortical-basal ganglia-cerebellar functional connectivity between treated unilateral vocal fold paralysis (UVFP) and healthy control cohorts using resting-state functional magnetic resonance imaging (RS-fMRI).

Study Design: Cross-sectional.

Methods: Ten UVFP study patients treated by type I thyroplasty and 12 control subjects underwent RS-fMRI on a 3-Tesla scanner to evaluate differences in functional connectivity of whole-brain networks. Spontaneous RS-fMRI data were collected using a gradient echo planar pulse sequence, preprocessed, and analyzed to compare seed-to-voxel maps between the two cohorts. Seeds were placed in the caudate, putamen, and globus pallidus divisions of the basal ganglia in both hemispheres. Group contrasts were tested for statistical significance using two-tailed unpaired t tests corrected for multiple comparisons with a cluster false discovery rate threshold of P < .05.

Results: UVFP patients demonstrated increased connectivity between both caudate nuclei and the precuneus, a node of the default mode network, compared to healthy controls. Both caudate nuclei also showed decreased connectivity with the left cerebellar hemisphere. The putamen and globus pallidus divisions of the basal ganglia were not abnormally connected to other brain structures.

Conclusions: UVFP patients treated by type I thyroplasty exhibited long-term alterations of cortical-basal ganglia-cerebellar networks thought to be important for self-referential voice quality awareness and learning processes that compensate for changes to the paralyzed hemilarynx. This pilot study on relatively small cohorts adds to growing evidence for persistent central nervous system changes in treated UVFP. Replication studies with larger numbers of subjects will be essential to validate and extend findings.

Level Of Evidence: 3b Laryngoscope, 130:460-464, 2020.