In-vivo tongue stiffness measured by aspiration: Resting vs general anesthesia

Tongue cancer treatment often results in impaired speech, swallowing, or mastication. Simulating the effect of treatments can help patient and treating physician to understand effects impact intervention. To simulate deformations tongue, identifying accurate mechanical properties tissue is essential. However, not many succeeded characterizing in-vivo tongue stiffness. Those who did, measured At Rest (AR), which muscle tone subsides even if muscles are willingly activated. We expected find an absolute rest state participants ‘under General Anesthesia’ (GA). elaborated on previous work by measuring behavior under aspiration using improved volume-based method. Using this technique, 5 7 measurements were performed 10 both AR GA. The obtained Pressure-Shape curves first analyzed initial slope its variations. Hereafter, inverse Finite Element Analysis (FEA) was applied identify parameters Yeoh, Gent, Ogden hyperelastic models. provided a mean Young’s Modulus 1638 Pa (min 1035 – max 2019) Yeoh constitutive model, line with ex-vivo measurements. while hoping GA, unexpectedly appeared be approximately 2 2.5 times stiffer GA than AR. Explanations for sought examining drugs administered during blood flow, perfusion, upper airway reflexes, but neither these explanations could confirmed.