Swallowing difficulty is one of the common medical problems in rehabilitation of stroke patients in subacute phase. VFSS is being commonly used for assessment of swallowing function of those patients but its value is still confusing because of too many parameters used in analysis. This study is performed to find most valuable parameters of VFSS that reflects swallowing status of stroke patients most correctly. A total of 97 subacute stoke patients with swallowing difficulty or aspiration symptoms were included. The results of VFSS were analyzed retrospectively to validate significance of each parameter. Swallowing status was assessed according to American Speech-Language-Hearing Association National Outcome Measurement System (ASHA NOMS) score. Among the time parameters of VFSS, pharyngeal delay time (PDT) and pharyngeal transit time (PTT) were inversely correlated with ASHA-NOMS (p=0.007 for PDT, 0.010 for PTT respectively), although absolute value of correlation coefficient was below 0.3 (-0.280 for PDT, -0.270 for PTT respectively). In addition, swallowing status was poorer (ASHA-NOMS less than 4) in those who showed inadequate oral bolus manipulation (n=17) (p=014 by Chi square). However, improvement of swallowing status was not associated statistically with any of parameters in follow-up VFSS. The results suggest that PDT, PTT and adequacy of oral bolus manipulation reflect swallowing status of subacute stroke patients although statistical power is not strong. Value of VFSS in prediction of prognosis of swallowing difficulty is still questionable in this patient group.

Parameters of Videofluoroscopic swallowing study (VFSS) that reflect swallowing status in stroke patients