Hyoid Bone Velocity and Distance during the Forward Phase Correlate with Pyriform Sinus Residue: A Retrospective Case Series.

Objectives: This study investigated the relationship between the three phases of hyoid bone movement and pharyngeal residue using the videofluoroscopic swallowing study (VFSS). Methods: We retrospectively analyzed the data from 66 patients who underwent VFSS between April 2019 and December 2019. Hyoid bone movement was classified into three phases: upward, forward, and downward. We measured the velocity and distance of hyoid bone movement in each phase, as well as the pharyngeal residue after swallowing. The correlation between hyoid bone movement and the amount of pharyngeal residue was analyzed using Spearman's rank correlation coefficient. A receiver operating characteristic (ROC) analysis was performed to evaluate the presence of pyriform sinus residue. Results: Hyoid bone velocity and distance during the forward phase correlated with the amount of pyriform sinus residue (velocity: r=0.311, P=0.011; distance: r=0.255, P=0.0389). ROC analysis revealed that the cutoff value for hyoid bone velocity during the forward phase was 26.1 mm/s (0.846 sensitivity, 0.604 specificity) with an area under the curve of 0.717. Conclusions: The velocity and distance of the hyoid bone during the forward phase were significantly related to the amount of pyriform sinus residue. In VFSS assessment, it is important to classify hyoid bone movement into three phases-upward, forward, and downward-and to calculate its velocity and distance.