Correlation Between the Basic Video Laryngostroboscopic Parameters and Multidimensional Voice Measurements

Abstract

The aim of this study is to evaluate the correlations among the basic video laryngostroboscopic (VLS) parameters and vocal function assessed using a multidimensional set of perceptive, acoustic, aerodynamic, and subjective measurements. Digital VLS recordings and multidimensional voice assessment were performed for 108 individuals, namely 26 healthy and 82 patients with mass lesions of vocal folds and paralysis. The VLS variables (glottal closure, regularity, mucosal wave on the affected/healthy side, symmetry of vibration, and symmetry of image) were rated and quantified on a visual analog scale. Correlations among the VLS parameters and results of acoustic voice analysis and voice range profile (VRP), data of subjective (voice handicap index [VHI] and glottal function index [GFI]), perceptual (G-grade, R-roughness, B-breathiness, A-asthenic scale), and dysphonia severity index (DSI) measurements were tested using Pearson's correlation coefficient. The intercorrelations of VLS parameters in vocal performance were moderate to strong and statistically significant for the entire functional measurements obtained through different modalities. The definitive correlations between VLS and VRP parameters were as follows: r=0.69-0.79 for normal profile coverage, r=0.67-0.76 for dynamic intensity, and r=0.67-0.74 for maximum intensity. All VLS parameters correlated moderately with VHI, GFI, and DSI (r=0.5-0.65, r=0.4-0.57, and r=0.61-0.69, respectively). The strongest correlations were found between VLS parameters and G factor of the GRBA scale (r=0.68-0.88). Correlation analysis of the vibratory pattern of the vocal folds obtained via VLS provides more comprehensive insight into the pathophysiology of phonation and suggests the documented and measurable evidence of complex mechanisms of vocal outcome.