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Published on: November 25, 2017
Prevalence of Vocal Tremor in the Vocal Tract
Kate E Henderson1, Laura Habich2, Leah B Helou1
1University of Pittsburgh, Department of Communication Science Disorders.
Objective:
This study investigates the prevalence of vocal tremor in specific vocal tract locations to provide insights that refine botulinum toxin injection treatments.
Methods:
A retrospective analysis was conducted on clinical data from 36 patients diagnosed with vocal tremor who received botulinum toxin injections at the University of Pittsburgh Medical Center Voice, Airway & Swallow Center between 2006 and 2024. Tremor locations (true vocal folds, false vocal folds, palate, strap muscles, tongue) were assessed using dynamic flexible laryngoscopic imaging.
Results:
Vocal tremor frequently involved multiple sites, with the most common locations being the true vocal folds (33 patients), palate (24 patients), and false vocal folds (23 patients). On average, patients exhibited tremor in 3 locations.
Conclusion:
Comprehensive laryngeal evaluation is crucial for tailoring botulinum toxin treatments. Future research should explore advanced diagnostic techniques and alternative therapies to address tremor in harder-to-treat locations.
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