Kinematic analysis of videofluoroscopic swallowing study data
DYSPHAGIA
For the VFSS, subjects were tested with the following boluses sequentially: thin fluid (International dysphagia diet standardization initiative (IDDSI) 0), mildly thick fluid (IDDSI 2), soft and bite-sized food (IDDSI 6), and regular food (IDDSI 7)Kinematic analysis was performed for the VFSS video clips. VFSS video clips were cut and recorded at 30 images/s. Two-dimensional hyoid bone tracking was performed using AKAP based on MATLAB (The MathWorks Inc., Natick, MA)This figure shows the automated kinematic analysis program (AKAP, C-2015-019815). (Based on the two-dimensional moving trajectory of the hyoid bone, four points were identified: point A was the starting point of the hyoid bone when swallowing, point B was the most upward point, point C was the most anterior location (equilibrium state of supra-and infrahyoid muscles), and point D was the endpoint of swallowing (Fig. 