Acoustic analysis of glottal gap measurement.

Abstract

A simple, efficient, noninvasive method for defining the size of the glottic gap in patients with dysphonia would be highly desirable. Current methods for defining the degree of insufficiency involve aerodynamic and videostroboscopic analysis. PARCOR analysis of the glottal area was calculated utilizing DAT recorded data obtained at a 44.1-kHz sampling rate from 15 patients with dysphonia, 14 of which presented unilateral recurrent laryngeal nerve paralysis. Ten thousand data points were calculated for each voiced sample. PARCOR coefficients were obtained and used as a basis for determining the cross-section area of vocal tract, i.e., the glottal area ratio (GAR). GAR, which is a noninvasive technique, was utilized successfully in the verification of the reduction in glottal gap of 15 patients who underwent medialization thyroplasty for glottis insufficiency. Results demonstrate that GAR utilizing PARCOR analysis corresponds favorably with findings obtained using well-attested methods of aerodynamic and videolaryngoscopic analysis.