[Objective evaluation of vocal pathology in childhood].
Voice disorders in children are often described as existing on a continuum with anatomic or physiologic causes at one end and functional or psychogenic causes at the other. In this study we report the objective evaluation of the voice disorders on 48 school children. The evaluation was made by means of laryngostroboscopy, acoustic analysis of the voice and narrow-band spectrography. The stroboscopic examination was performed on more than a half of the patients, resulting in the change of diagnose in six cases. The severity of the hoarseness was classified in four groups according Yanagihara method. A multivariate analysis was carried out using jitter, shimmer and harmonic-to-noise ratio as variables. Only the harmonic-to-noise ratio predicts the severity of the spectrographic record. Classification of degrees of hoarseness is found to be clinically useful in two respects: the degree of hoarseness can be numerically expressed and the objective acoustic degree of hoarseness based on this method closely agrees with subjective perceived degree of hoarseness.