2026 American Academy of Neurology Abstract Website

Objective:

To define swallowing outcomes after deep brain stimulation (DBS) for dystonia and determine clinical and stimulation factors associated with swallowing safety and efficiency.

Background:

DBS provides long-lasting motor benefit in dystonia, yet its effects on swallowing, a vital function for airway protection remain underexplored. Bulbar outcomes are inconsistently reported and often lack objective quantification. Identifying clinical or stimulation-related predictors of swallowing change could refine patient selection toward safer, individualized DBS programming.

Design/Methods:

We retrospectively reviewed 75 dystonia patients who underwent DBS at the University of Florida (2003–2024; GPi = 56, VIM = 12, STN = 4, STN + GPi = 3). Motor outcomes were assessed with the Unified Dystonia Rating Scale, Toronto Western Spasmodic Torticollis Rating Scale, and Burke–Fahn–Marsden Dystonia Rating Scale. Swallowing safety and efficiency were evaluated with the Penetration–Aspiration Scale (PAS) and Dynamic Imaging Grade of Swallowing Toxicity (DIGEST). Pre- and postoperative scores were compared using Wilcoxon signed-rank tests (FDR-corrected). Multivariable regression identified predictors of PAS change, adjusting for baseline PAS, age, disease duration, etiology, phenotype, motor severity, follow-up, and stimulation energy.

Results:

DBS improved motor scores across all scales (p < 0.01). Subscores related to orobulbar control, including jaw/tongue and speech-swallowing domains also improved, suggesting concurrent benefit in axial function. Median PAS remained stable, indicating preserved swallowing safety. The regression model for PAS change was significant (F-test p = 0.046; adjusted R² = 0.46). Higher baseline PAS scores predicted greater postoperative improvement (p = 0.075, trend level), whereas no demographic or stimulation parameters correlated with decline. DIGEST models were non-significant.

Conclusions:

DBS preserved swallowing safety and efficiency and may benefit patients with more severe swallowing impairment. These findings suggest that DBS modulates pallido–brainstem networks, supporting bulbar coordination without compromising airway protection. Baseline PAS may serve as a marker of postoperative trajectory, supporting a more personalized approach to DBS in dystonia.