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Quantification of vocal tract configuration of older children with Down syndrome: a pilot study
Steve An Xue1, Laura Kaine, Manwa L Ng
1Division of Speech and Hearing Sciences, The University of Hong Kong, Pokfulam, Hong Kong. axue@hkucc.hku.hk
Objective:
To quantify the vocal tract (VT) lumen of older children with Down syndrome using acoustic reflection (AR) technology.
Design:
Comparative study.
Setting:
Vocal tract lab with sound-proof booth.
Participants:
Ten children (4 males and 6 females), aged 9-17 years old diagnosed with Down syndrome. Ten typically developing children (4 males and 6 females) matched for age, gender, and race.
Intervention:
Each participant's vocal tract measurements were obtained by using an Eccovision Acoustic Pharyngometer.
Main Outcome Measures:
Six vocal tract dimensional parameters (oral length, oral volume, pharyngeal length, pharyngeal volume, total vocal tract length, and total vocal tract volume) from children with Down syndrome and the typically developing children were measured and compared.
Results:
Children with Down syndrome exhibited small oral cavities when compared to control group (F(1,18)=6.55, p=0.02). They also demonstrated a smaller vocal tract volumes (F(1,18)=2.58, p=0.13), although the results were not statistically significant at the 0.05 level. Pharyngeal length, pharyngeal volume, and vocal tract length were not significantly different between the two groups.
Conclusion:
Children with Down syndrome had smaller oral cavities, and smaller vocal tract volumes. No significant differences were found for pharyngeal length, pharyngeal volume, and vocal tract length between these two groups.
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