2016 Volume 28 Issue 2 Pages 54
Laryngeal stroboscopy and high-speed digital imaging (HSDI) of the larynx are methods that allow for the intuitive evaluation of vocal cord vibration based on visual information. Both examinations enable the objective evaluation of vocal cord vibration based on information obtained from imaging. However, previous studies have revealed that HSDI is superior to stroboscopy in certain areas. To analyze the objective information from HSDI, we performed a kymograph edge analysis (KEA) and used the glottal area waveform (GAW) to evaluate the vocal cord vibration of the patients with various laryngeal diseases. Moreover, we developed a software program that can automatically calculate the anterior to posterior and left to right phase difference from KEA. We noticed a slight difference in both the amplitude and duration of vocal cord vibration in each glottal cycle. We referred to this as “perturbation of vocal cord vibration” and hypothesized that this perturbation is associated with conventional factors that cause perturbation in the acoustic analysis. We compared the perturbation data from HSDI and the acoustic analysis. A significant correlation in the degree of perturbation was observed in the two examinations. The results of our study suggest that HSDI could be used to evaluate perturbation of the vocal cord vibration in each glottal cycle.
