Spatiotemporal Disturbance of Fine Movements in Adductor Spasmodic Dysphonia

The goal of this research is to study the use new imaging tool called the high speed digital imaging to identify key components of vocal fold motion disturbance responsible for vocal spasms and strained, strangled voice quality in patients with adductor spasmodic dysphonia. The battery of tests that are currently used to clinically test vocal fold vibrations, result in invalid assessments in participants with severe dysphonia, like that of spasmodic dysphonia, due to inherent limitations of the instruments. High speed digital imaging however can capture upto 8000 frames per second; hence can be used to evaluate the small and rapid changes of vocal fold vibrations. Simultaneous laryngeal electromyographic recordings will be performed high speed digital imaging to investigate the muscle activity responsible for the unique vibratory features observed in participants with spasmodic dysphonia ... Results from this study will assist in clinical decision making regarding treatment with unilateral vs. bilateral botulinum toxin injections. The findings of this study will also help investigate the much needed short-term and long-term outcomes of voice quality and vocal fold motion, following botulinmn toxin in patients with spasmodic dysphonia.