Vibratory Pattern and Mucosal Wave Differences Between Children With Nodules and Vocally Healthy Children

A systematic investigation of the posterior glottal gaps, opening and closing vibratory patterns, and mucosal wave amplitude in children with nodules compared to vocally healthy controls.

High-speed videoendoscopy (HSV) recordings were obtained from 20 children with vocal fold nodules (10 boys, 10 girls). Sustained phonation on vowel /i:/ was elicited. The posterior glottal gap, the mucosal wave amplitude, and the opening and closing phase anterior-posterior (AP) vibratory patterns along the entire vocal folds (VFs) and at the nodule location were rated by two raters, using a custom visualization tool. Similarly, data obtained from vocally healthy adults and children from a previous study were used as control. Between groups, differences were assessed using Pearson's chi-square, followed by post hoc Mann-Whitney U tests.

Posterior glottal gaps were more frequent in girls with nodules, compared with specific vocally healthy control groups, particularly adult men (P < 0.001), who showed fewer and smaller gaps. Opening patterns initiating posteriorly were common across pediatric groups; however, boys with nodules exhibited mostly opening patterns initiating at the ends (P < 0.001). Children with nodules, especially girls, demonstrated mostly the middle progressing toward both ends or simultaneous closure, while control girls (P < 0.05) and women (P < 0.01) mostly showed an anterior-to-posterior pattern. The male groups showed less differences. In the vibratory patterns at the nodule location, no statistically significant influence of sex was visible. Opening at the nodule most frequently occurred later relative to other locations, while simultaneous closing was the most frequent closing pattern.

This study identified sex- and pathology-related differences in pediatric VF vibration, particularly in glottal gap configuration, AP vibratory coordination, and mucosal wave amplitude. The findings offer valuable benchmarks for visual-perceptual assessment and highlight the diagnostic potential of HSV in differentiating healthy pediatric voice production from pathology.