The goal of surgical medialization of the vocal fold is to attain complete glottic closure. The purpose of this study is to quantify the glottal gap and to examine the relationship between glottal gap and vocal function perioperatively in thyroplasty type I. Glottal gap area was measured in 20 patients at the point of maximum closure of vocal fold vibration in digitized laryngeal stroboscopic images and was normalized by the square of vocal fold length. Glottal gap area thus measured was correlated with results obtained from well-accepted acoustic, aerodynamic, and perceptual measures of vocal function. The glottal gap was significantly reduced after thyroplasty type I. In patients with small preoperative glottal gaps, the amplitude of vocal fold vibration was significantly improved. This study verifies that quantitative videostroboscopic measurement of the glottal gap is a useful means of objective evaluation of glottic incompetence and of the results of thyroplasty type I.

Arytenoid adduction as described by Isshiki is a surgical technique used to improve vocal quality by adducting the arytenoid cartilage of a paralyzed vocal fold, medializing the fold, and closing the posterior glottic aperture. Surgical results of this operation were evaluated by preoperative and postoperative voice recordings, laryngoscopy, and stroboscopy. Objective measurements of vocal jitter, shimmer, and signal to noise ratio were done to assess changes in the vibratory patterns, and analysis of data from 12 patients revealed improved glottic function postoperatively. Often an anterior medialization procedure, primarily a type I thyroplasty, was used to supplement the posterior medialization achieved by adduction of the arytenoid. Arytenoid adduction is recommended as an effective and reliable treatment for posterior glottic insufficiency.

Videostroboscopic glottic measurements and vocal function were evaluated in 41 vocal fold atrophy patients with bowed vocal folds. The amount of bowing in the resting position and the glottal gap area and vibratory amplitude during phonation were measured from digitized videostroboscopic images. Vibratory amplitude was not decreased on atrophic vocal folds. With the same amount of total bowing, the glottal gap area for bilateral atrophy was smaller than for unilateral atrophy. These results suggest that vocal fold atrophy is not disadvantageous to thyroplasty type I, and that bilateral procedures may produce a better outcome than a unilateral procedure in the treatment of bilateral atrophy. Acoustic, aerodynamic, and perceptual parameters of vocal function were measured. The acoustic high-frequency power ratio and the H-index correlated with the glottal gap area. The mean flow rate correlated with the amount of bowing. The degree of dysphonia was related to the size of the glottal gap and bowing.

No abstract

This study investigates the relationship between glottal gap and vocal function in patients with glottic incompetence dysphonia. Twenty patients with vocal fold paralysis (VFP), 17 patients with vocal fold atrophy (VFA), and five patients with sulcus vocalis (SV) were examined. Glottal gap area at the most closed point of vibration was measured using digitized videostroboscopic images. Glottal gap area was correlated with acoustic and aerodynamic measures of vocal function. Patients with VFP had the largest glottal gaps and had significantly worse vocal function than did the patients with VFA or SV. Regardless of groups, however, where glottal gap size was similar, there was no difference in vocal function. Therefore vocal function was mainly influenced by glottal gap size, not by whether glottic incompetence was the result of VFP, VFA, or SV.