2012 Volume 53 Issue 4 Pages 329-335
Purpose: Criteria for spasmodic dysphonia (SD) as an independent voice disorder have not yet been established, and the current standardized assessment method is not sufficient for objective evaluation of severity or its effects. The purpose of this study was to quantitatively evaluate phonatory breaks and to demonstrate the characteristics of voice symptoms in abductor spasmodic dysphonia (ABSD).
Method: Subjects included eight patients with ABSD and ten normal controls. We measured voice onset time (VOT) for the word-initial voiceless consonant /ta/ in the word "taiyo" under three different conditions (1. without punctuation, 2. with a comma, and 3. with a period) which appeared in the reading task "kitakaze to taiyo."
Results: Under the conditions in which a comma or period was included, the patients' VOTs for the word-initial voiceless consonant were significantly longer than those of the controls. Prolongation of the VOTs was related to the length of the silence preceding the syllables.
Conclusion: VOT measurement for the word-initial voiceless consonant was suggested to be a useful method to quantify voice symptoms of ABSD.
