A micro-mechanical model of the vocal-fold upper layers

International audienceThe vocal folds are soft multi-layered laryngeal tissues, owning remarkable vibro-mechanical performances. Composed of collagen and elastin microfibrils' networks, the upper layers play a major role in the vocal-fold vibrations. However, the impact of these tissues' histological features on their mechanical behavior is still poorly known. This is mainly ascribed to their challenging experimental characterization: vocal folds together with their fibrous architectures are not easily observable in vivo; ex vivo mechanical tests are rare and complex to interpret [1]. Consequently, most of the vocal-fold mechanical models developed so far rely on phenomenological macroscopic approaches, roughly assuming a homogeneous vocal tissue with linear-elastic properties. Since 2010, a few authors have started to investigate and model the vocal-tissue collagenous fibrous microstructure, opening a new insight into voice biomechanics [2]. Theoretical formulations at the fiber scale still need to be developed. Thereby, this study aims at: (i) proposing an idealized but relevant model of the fibrous architecture of the vocal-fold upper layers; (ii) building a mechanical model able to predict the layers' multiscale properties from the above idealized architectures; (iii) assessing its relevance by comparison with a reference tensile database