Predominant Vertical Location of Benign Vocal Fold Lesions by Sex and Music Genre: Implication for Pathogenesis

Voice efficiency for different voice qualities combining experimentally derived sound signals and numerical modeling of the vocal tract

Purpose: Concerning voice efficiency considerations of different singing styles, from western classical singing to contemporary commercial music, only limited data is available to date. This single-subject study attempts to quantify the acoustic sound intensity within the human glottis depending on different vocal tract configurations and vocal fold vibration. Methods: Combining Finite-Element-Models derived from 3D-MRI data, audio recordings, and electroglottography (EGG) we analyzed vocal tract transfer functions, particle velocity and acoustic pressure at the glottis, and EGG-related quantities to evaluate voice efficiency at the glottal level and resonance characteristics of different voice qualities according to Estill Voice Training^®. Results: Voice qualities Opera and Belting represent highly efficient strategies but apply different vowel strategies and should thus be capable of predominate orchestral sounds. Twang and Belting use similar vowels, but the twang vocal tract configuration enabled the occurrence of anti-resonances and was associated with reduced vocal fold contact but still partially comparable energy transfer from the glottis to the vocal tract. Speech was associated with highly efficient glottal to vocal tract energy transfer, but with the absence of psychoactive strategies makes it more susceptible to noise interference. Falsetto and Sobbing apply less efficiently. Falsetto mainly due to its voice source characteristics, Sobbing due to energy loss in the vocal tract. Thus technical amplification might be appropriate here. Conclusion: Differences exist between voice qualities regarding the sound intensity, caused by different vocal tract morphologies and oscillation characteristics of the vocal folds. The combination of numerical analysis of geometries inside the human body and experimentally determined data outside sheds light on acoustical quantities at the glottal level.

Association of Genre of Singing and Phonotraumatic Vocal Fold Lesions in Singers

OBJECTIVES/HYPOTHESIS

To determine if (1) the likelihood of presenting with phonotraumatic lesions differs by singing genre in treatment-seeking singers and (2) if the distribution of phonotraumatic lesion types differs by singing genre.

STUDY TYPE

Retrospective.

METHODS

Records of singers who presented with a voice complaint over the course of 2.5 years (June 2017-December 2019) were reviewed to determine the proportion of those with phonotraumatic lesions as a function of genre (Study 1). Separately, the lesion types and genres of singers diagnosed with phonotraumatic lesions over a 9-year period (July 2011-March 2020) were determined (Study 2).

RESULTS

In Study 1, 191 of 712 (26.8%) dysphonic singers were diagnosed with phonotraumatic lesions. Country/folk, gospel/jazz, and musical theater singers were more likely to present with phonotraumatic lesions. In Study 2, in 443 singers with phonotraumatic lesions, polyps and pseudocysts, but not nodules, were found to be distributed unequally across genres (χ² p = 0.006, p < 0.0001, p = 0.064, respectively). Praise/worship singers had significantly higher proportions of polyps compared to choral singers (OR 4.8 [95% CI 1.9-12.5]) or compared to musical theater singers (OR 7.2 [95% CI 2.5-20.8]). Opera singers had significantly higher proportions of pseudocysts than choral singers (OR 3.1 [95% CI 1.5-6.1]) or musical theater singers (OR 3.7 [95% CI 1.8-7.6]).

CONCLUSIONS

The higher incidence of polyps in praise/worship singers likely reflects the more emphatic nature of singing and the tendency for acute injury. The higher incidence of pseudocysts in opera singers may reflect a more chronic nature of injury.

LEVEL OF EVIDENCE

4 Laryngoscope, 2023.