Nasal rustle: The retrospective and prospective investigation of effects of bubbling of secretions on speech

The Source of Nasal Rustle (Nasal Turbulence): An Overview of Current Evidence

OBJECTIVE

Nasal rustle (also called nasal turbulence) refers to a loud distracting sound that sometimes occurs with audible nasal emission (ANE) during the production of pressure-sensitive consonants in patients with velopharyngeal insufficiency (VPI). This article examines evidence for two hypotheses of causality: vibration of the soft palate (velar flutter) and periodic motion of mucus above the velopharyngeal port (turbulent mucus).

CONCLUSION

A review of the relevant literature shows inconclusive evidence to support velar flutter as a cause of nasal rustle. In contrast, clinical observations and research involving high-speed nasopharyngoscopy suggest that nasal rustle is the result of turbulent mucus above a small velopharyngeal opening. Therefore, it is our contention that a plausible explanation for nasal rustle is one of turbulent mucus and not velar flutter.

Models for Predicting Velopharyngeal Competence Based on Speech and Resonance Errors and Velopharyngeal Area Estimation

OBJECTIVE

To develop tools for predicting velopharyngeal competence (VPC) based on auditory-perceptual assessment and its correlation with objective measures of velopharyngeal orifice area.

DESIGN

Methodological study.

PARTICIPANTS AND METHODS

Sixty-two patients with repaired cleft palate, aged 6 to 45 years, underwent aerodynamic evaluation by means of the pressure-flow technique and audiovisual recording of speech samples. Three experienced speech-language pathologists analysed the speech samples by rating the following resonance, visual, and speech variables: hypernasality, audible nasal air emission, nasal turbulence, weak pressure consonants, facial grimacing, active nonoral errors, and overall velopharyngeal competence. The correlation between the perceptual speech variables and velopharyngeal orifice area estimates was analysed with Spearman's correlation coefficient. Two statistical models (discriminant and exploratory) were used to predict VPC based on the orifice area estimates. Sensitivity and specificity analyses were performed to verify the clinical applicability of the models.

RESULTS

There was a strong correlation between VPC (based on the orifice area estimates) and each speech variable. Both models showed 88.7% accuracy in predicting VPC. The sensitivity and specificity for the discriminant model were 92.3% and 97.2%, respectively, and 96.2% and 94.4% for the exploratory model.

CONCLUSION

Two predictor models based on ratings of resonance, visual, and speech variables and a simple calculation of a composite variable, SOMA (Eng. "sum"), were developed and found to be efficient in predicting VPC defined by orifice estimates categories based on aerodynamic measurements. Both tools may contribute to the diagnosis of velopharyngeal dysfunction in clinical practice.