Failed Deglutitive Upper Esophageal Sphincter Relaxation Is a Risk Factor for Aspiration in Stroke Patients with Oropharyngeal Dysphagia

BACKGROUND/AIMS: 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. METHODS: 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, and 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. RESULTS: 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 the pyriform sinus were significantly lower than those in patients without residue in the pyriform sinus (P < 0.05). 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 (OR, 0.03; 95% CI, 0.01–0.65; P < 0.05). CONCLUSIONS: 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.

Videofluoroscopic and Manometric Evaluation of Pharyngeal and Upper Esophageal Sphincter Function During Swallowing

BACKGROUND/AIMS: The purpose of this study was to determine important manometric metrics for the analysis of pharyngeal and upper esophageal sphincter (UES) function and to investigate the effect of viscosity and other confounding factors on manometric results. METHODS: Manometric studies were performed on 26 asymptomatic volunteers (12 men and 14 women; age, 19-81 years). The manometric protocol included 5 water swallows (5 mL), 5 barium swallows (5 mL) and 5 yogurt swallows (5 mL). Evaluation of high-resolution manometry parameters including basal pressure of the UES, mesopharyngeal contractile integral (mesopharyngeal CI, mmHg . cm . sec), CI of the hypopharynx and UES (hypopharyngeal CI), relaxation interval of UES, median intrabolus pressure and nadir pressure at UES was performed using MATLAB. RESULTS: Mesopharyngeal CIs for barium and yogurt swallows were significantly lower than those for water swallows (both P < 0.05). Hypopharyngeal CIs for water swallows were significantly lower than those for barium swallows (P = 0.004), and median bolus pressure at UES for barium swallows was significantly higher than that for water and yogurt swallows (both P < 0.05). Furthermore, hypopharyngeal CI and median intrabolus pressure at UES were significantly related to age for 3 swallows (all P < 0.01 and P < 0.05, respectively). A significant negative correlation was also noted between nadir pressure at UES and age for water and yogurt swallows (all P < 0.05). CONCLUSIONS: Manometric measurement of the pharynx and UES varies with respect to viscosity. Moreover, age could be a confounding variable in the interpretation of pharyngeal manometry.