We attempted to examine the relationship between abnormal findings on high-resolution manometry (HRM) and videofluoroscopic swallowing study (VFSS) of the pharynx and upper esophageal sphincter (UES) and to identify the risk factors for aspiration.
We performed VFSS and HRM on the same day in 36 ischemic stroke patients (mean age, 67.5 years) with dysphagia. Pressure (basal, median intra bolus, nadir), relaxation time interval of the UES, and mesopharyngeal and hypopharyngeal contractility (as a contractile integral) were examined using HRM. The parameters of VFSS were vallecular residue, pyriform sinus residue, vallecular overflow, penetration, and aspiration. The association between the parameters of VFSS and HRM was analyzed by the Student’s t test.
Three (8.3 %) and 4 (11.1 %) stroke patients with dysphagia had pyriform sinus residue and vallecular sinus residue, respectively, and 5 (13.8%) patients showed aspiration. Mesopharyngeal and hypopharyngeal contractile integrals in patients with residue in pyriform sinus were significantly lower than those in patients without residue in pyriform sinus (P < 0.05, respectively). Relaxation time intervals in patients with aspiration were significantly shorter than those in patients without aspiration (P < 0.05), and multivariate regression analysis revealed a shorter relaxation time interval as the main risk factor for aspiration (odds ratio, 0.025; 95% confidence interval, 0.001-0.652).
Manometric measurements of the pharynx and UES were well correlated with abnormal findings in the VFSS and a shorter relaxation time interval of the UES during deglutition is an important parameter for the development of aspiration.