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[Role of aerodynamic parameters in voice function assessment]
Yong-qing Guo1, Sheng-zhi Lin, Xin-lin Xu
1Department of Otorhinolaryngology, Zhongshan Hospital Affiliated Xiamen University, Xiamen, China.
Objective:
To investigate the application and significance of aerodynamic parameters in voice function assessment.
Methods:
The phonatory aerodynamic system (PAS) was used to collect aerodynamic parameters from subjects with normal voice, vocal fold polyp, vocal fold cyst, and vocal fold immobility. Multivariate statistical analysis was used to compare measurements across groups.
Results:
Phonation threshold flow (PTF), mean flow rate (MFR), maximum phonation time (MPT), and glottal resistance (GR) in one hundred normal subjects were significantly affected by sex (P < 0.05), while phonation threshold pressure (PTP), subglottal pressure (SGP), and vocal efficiency (VE) were not (P > 0.05). PTP, PTF, MFR, SGP, and MPT were significantly different between normal voice and voice disorders (P < 0.01), and there were no significant differences among the three disorders (P > 0.05). Receiver operating characteristic (ROC) analysis found that PTP, PTF, SGP, MFR, MPT, and VE in one hundred thirteen voice dis orders had similar diagnostic utility (P < 0.01), with PTP exhibiting the highest area under the curve. The aerodynamic parameters of the three degrees of voice dysfunction due to vocal cord polyps were compared and found to have no significant differences (P > 0.05). PTP, PTF, MFR, SGP and MPT in forty one patients with vocal polyps were significantly different after surgical resection of vocal cord polyps (P < 0.01).
Conclusion:
The aerodynamic parameters can objectively and effectively evaluate the variations of vocal function, and have good auxiliary diagnostic value.
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