Stroboscopy versus high-speed glottography: a comparative study.

Abstract

To evaluate and to compare the diagnostic value of videostroboscopy (VS) and high-speed glottography (HGG) in dysphonic patients. Randomized, prospective study. A total of 162 patients underwent indirect laryngoscopy using both methods (VS and HGG). The resulting 324 films were evaluated by two professionals (laryngologists, MDs) using a standardized protocol containing established criteria to classify vocal fold vibratory movement qualities. The rating "not assessable" was mentioned significantly more often in VS than in HGG (P < .001). In HGG, methodologic failures were less frequent, and the length of investigation was shorter. Even if the agreement between the two raters was higher in HGG (54%) compared with VS (42%), both percentage values show a low accordance in diagnostic findings. Regardless of the method used (VS or HGG), perceptive evaluations of vibratory movements of vocal folds revealed a higher variability than assumed. This result supports the need for objective methods to analyze vocal fold vibratory movements. Therefore, real-time imaging of vocal fold vibratory movements using HGG will be necessary.