The Nasality Severity Index: An Objective Measure of Hypernasality Based on a Multiparameter Approach

Abstract

There is a need for an objective measure that describes normal resonance and resonance disorders. The current standard of practice has not led to mismanagement but a refined objective assessment protocol will benefit a more precise objective assessment of velopharyngeal disorders. The purpose of the present study is to construct a nasality severity index (NSI) that reflects the multidimensional nature of resonance. Objective and subjective assessment techniques were used to determine the nasalance, the nasality and aerodynamic capacities in 21 children with cleft palate and a control group of 25 children without cleft palate. Stepwise logistic regression was used to determine the optimal index. The NSI consists of a linear combination of 4 variables, where each variable has a different weight. The equation is: NSI = –60.69 – (3.24 × percent oral text) – (13.39 × Glätzel value /a/) + [0.244 × maximum duration time (seconds)] – (0.558 × % /a/) + (3.38 × percent oronasal text). NSI sensitivity is 88% and specificity is 95%. Daily clinical use of the NSI has shown it to be an efficient and practical tool to describe the presence of hypernasality. Three distinct follow-up cases are presented to illustrate the impact of a surgical technique, the use of a speech bulb and velopharyngeal biofeedback training on NSI. The implementation of the NSI may help clinicians to quantitatively assess the severity of nasality disorders beside the perceptual judgments.

Effects of Age and Gender in Normal-Speaking Children on the Nasality Severity Index: An Objective Multiparametric Approach to Hypernasality

“…To determine the degree of nasality, several specialists rely on perceptual measurements as well as objective measurements such as aerodynamic and acoustic characteristics. According to several authors [1,2,3], these subjective and objective measurements have to be interpreted with care and can lead to contradictory results when assessing the nasality of an individual person. This suggests the need for an objective measurement for determining nasal resonance disorders by using a multivariate approach.…”

“…However, several authors [7,8] have indicated the risk in determining nasality based on a single assessment protocol and suggested a combination of both instrumental assessment and perceptual judgment. Moreover, Van Lierde et al [1] reported a large overlap between some isolated nasalance values when groups of subjects with normal nasality and slight hypernasality were compared. Furthermore, perceptual judgments do not always agree with instrumental assessment [8,9].…”

Nasalância de populações falantes do português brasileiro de dois estados distintos

“…It is a subjective method which depends on the experience of the examiners, with risk of intra-and/or inter-rater discordance (4)(5)(6) . Therefore, the use of instrumental methods is important to complement this clinical evaluation, as well as to allow better planning and monitoring of the results of therapeutic procedures (4,7,8) .…”

Adult Tonsillectomy: Anatomical Differences Affect Postoperative Transient Hypernasality

“…The term hypernasality refers to an auditory impression related to speech [7]. The most important physical variable determining the degree of nasality in healthy patients is the opening and closing of the velopharyngeal passageway between the oral vocal and the nasal tract [8].…”