Measurement of the Viscoelastic Properties of the Vocal Folds

• Published in: Annals of otology, rhinology & laryngology rhinology & laryngology, 2009-06, Vol.118 (6), p.461-464
• Main Authors: Wiikmann, Christian, da Silva, Marcelo Alves, Arêas, Elizabeth Pinheiro Gomes, Tsuji, Domingos Hiroshi, Sennes, Luiz Ubirajara
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Cadaver; Compressive Strength - physiology; Elasticity; Female; Humans; Laryngeal Mucosa - physiopathology; Male; Medical sciences; Middle Aged; Otorhinolaryngology. Stomatology; Rheology; Tissue Culture Techniques; Viscosity; Vocal Cords - physiopathology
• ISSN: 0003-4894; 1943-572X
• DOI: 10.1177/000348940911800609

Objectives Studies of the viscoelastic properties of the vocal folds are normally performed with rheometers that use parallel plates whose interplate space is usually arbitrarily assigned a fixed value. In tissues subject to variation of thickness between samples, fixed gaps could result in different compressions, compromising the comparison among them. We performed an experimental study to determine whether different compressions can lead to different results in measurements of dynamic viscosity (DV) of vocal fold samples. Methods We measured the DV of vocal fold samples of 10 larynges of cadavers under 3 different compression levels, corresponding to 0.2, 0.5, and 10 N on an 8-mm-diameter parallel-plate rheometer. Results The DV directly varied with compression. We observed statistically significant differences between the results of 0.2 and 10 N (p = 0.0396) and 0.5 and 10 N (p = 0.0442). Conclusions The study demonstrated that the level of compression influences the DV measure and suggests that a defined compression level should be used in rheometric studies of biological tissues.