| Abstract: |
The study investigated whether acoustic speech measures permitted effective clinical assessment of the effects of botulinum toxin treatment (BT) in an individual with adductor spasmodic dysphonia (ADSD). A 54-year-old male diagnosed with ADSD was tracked over a span of 26 months of BT treatment. Seven BT injections were administered during that time span. A total of 24 audio recordings of the participant reading the "Rainbow Passage" (Fairbanks, 1960) aloud were made pre- and postinjections. Short-term and long-term effects of treatment were evaluated using temporal acoustic measurements. Anticipated voice improvement was observed following treatment and there were statistically significant differences, in the immediate pre- versus postinjection readings for total pause time and total articulation time. Statistically significant improvement over the long term was found for total speaking time, total pause time, and words per minute, but not in total articulation time. Linear regression analysis showed a statistically significant relationship between duration of BT therapy and magnitude of clinical change across the 24 readings. That is, as time in treatment increased, postinjection rate of speech also increased. In addition to expected short-term improvements, there was also cumulative long-term improvement in response to BT injections. Temporal acoustic analyses of connected speech proved useful for quantifying short- and long-term treatment-related change. |
