How Age and Frequency Impact the Thyroid Cartilages of Professional Singers.

OBJECTIVES/HYPOTHESIS: Young professional singers can easily reach very high pitches. In contrast, older singers often complain that they have to exert substantially more laryngopharyngeal force to reach the same high pitch compared with their earlier years. Various factors such as the property changes of the mucosa and ossification that impact the singing apparatus were suggested as explanations in the literature. The aim of this study was to analyze thyroid deformation-and thereby stiffness indirectly-during singing as a potential reason for this phenomenon.

STUDY DESIGN: Prospective study.

METHODS/DESIGN: We examined 44 female professional singers. High-resolution computed tomography scans were performed during singing at the fundamental mean speaking frequency and the first and second octaves above it. Digital Imaging and Communications in Medicine scan data were rendered and visualized 3-dimensionally using MIMICS software. By superimposition of the different 3-dimensional images, different positions of the thyroid were visualized. The distance from the posterior border of the thyroid was measured in all the examinations.

RESULTS: All laryngeal cartilages could be three-dimensionally visualized. The magnitude of the thyroidal deformation significantly depends on pitch and significantly correlates with age (r2  = 0.7, P < 0.001).

CONCLUSIONS: The thyroid cartilage is flexible and its formability is especially important during singing. At higher pitches, the cartilage was more deformed. The larynx in older singers showed less thyroid cartilage deformation.