Analysis of video fluoroscopic swallowing study in patients with vocal cord paralysis

Abstract

We reviewed the findings of a video fluoroscopic swallowing study (VFSS) of 28 patients with vocal cord paralysis (VCP) who complained of swallowing difficulties. VFSSs were performed with thick and thin liquid using modified Logemann methods. The patients were grouped according to whether their VCP was of central or peripheral origin, and the VFSS findings of the groups were compared. The patients showed oral phase dysfunction and pharyngeal dysfunction, especially when the cause was of central origin. Oral phase abnormalities were found in 13 patients and pharyngeal phase abnormalities were found in all patients, including penetration in 20 patients and aspiration in 14 patients. Improper lip closure (LC) and bolus formation (BF) and a delay in triggering pharyngeal swallow (TPS) and upper esophageal sphincter release (UESR) were significantly more frequent in patients with central VCP. With thin-liquid swallowing, pharyngeal transit time (PTT) and pharyngeal delay time (PDT) were significantly more prolonged in central VCP. The results suggest that the delay in triggering and poor coordination of swallowing were profound in patients with central VCP, but dysfunction in peripheral VCP may originate from poor pharyngeal movement.

Fig. 1

Comparison of pharyngeal delay time and pharyngeal transit time between groups. With thin-liquid swallowing, the pharyngeal transit (PTT) and pharyngeal delay times (PDT) were significantly longer in the central VCP group (P = 0.003 and P = 0.016 by Mann–Whitney test, respectively). The PTT and PDT with thick liquids were also longer in the central VCP group, but the differences were not statistically significant