A computational framework for patient-specific surgical planning of type I thyroplasty*

In the present study, a patient-specific computational framework has been proposed to determine the shape of the implant that results in the optimal acoustic and aerodynamic outcomes of the type I medialization surgery for unilateral vocal fold paralysis (UVFP) treatment. The framework combines a three-dimensional high-fidelity continuum model of fluid-structure-acoustics interactions (FSAI) of vocal fold vibrations, a laryngeal muscle mechanics model of vocal fold pre-phonatory posturing, and a genetic algorithm for optimization. The individual control of each muscle provides the opportunity to generate healthy and unilateral-paralyzed laryngeal postures through symmetric and asymmetric activations of the laryngeal muscles, respectively. The implant is virtually inserted into the paretic vocal fold in the cases representing UVFP to mechanically correct the laryngeal postures. The optimization is coupled with FSAI simulations to determine the implant shape that produces the best aerodynamic and acoustic features. The preliminary results show that the optimized implant shapes improved the aerodynamic and acoustic features of the voice compared to the UVFP case.