title: Effect of bolus volume on pharyngeal swallowing assessed by high-resolution manometry.
abstract: OBJECTIVE
  Solid-state high-resolution manometry (HRM) is fast becoming the gold standard for studying pharyngeal and esophageal motility. However, very few studies have ever evaluated the effect of bolus volume on the physiology of swallowing using HRM. We aimed to determine the effect of bolus volume on pressure, duration and velocity of the hypopharynx as well as the upper esophageal sphincter during pharyngeal swallowing using HRM.
  
  
  METHODS
  Thirty-four healthy subjects completed nine swallows (3 ml, 5 ml and 10 ml of water, thick liquid, and paste, respectively) in the natural sitting position. Pressure and duration measurements were acquired from the hypopharynx and upper esophageal sphincter (UES) using HRM. The UES residual pressure, UES relaxation duration, maximum preopening UES pressure, maximum postclosure UES pressure, maximum hypopharyngeal pressure, maximum hypopharyngeal pressure rise rate and hypopharyngeal pressure duration were analyzed across bolus volumes using repeated measures of one-way analysis of variance.
  
  
  RESULTS
  A significant increase in UES residual pressure associated with increased bolus volume during water and paste swallowing was observed. Furthermore, UES relaxation duration was significantly increased with increasing in bolus volume for all three material swallows. No significant volume effects were found on the hypopharynx.
  
  
  CONCLUSIONS
  In summary, bolus volume has a significant effect on the residual pressure and relaxation duration, but no effect on maximum preopening pressure or maximum postclosure pressure of the UES. Maximum hypopharyngeal pressure, maximum hypopharyngeal pressure rise rate and pressure duration were also not affected by bolus volume. Consideration of these variables is paramount in understanding normal and pathological swallowing.
authors: Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors: Tuo
authors: T
authors: Lin
authors: Department of Rehabilitation Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors: Guangqing
authors: G
authors: Xu
authors: Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors: Zulin
authors: Z
authors: Dou
authors: Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. Electronic address: bluemooning@163.com.
authors: Yue
authors: Y
authors: Lan
authors: Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors: Fan
authors: F
authors: Yu
authors: Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors: Lisheng
authors: L
authors: Jiang
mesh_terms: D000328:Adult; D003679:Deglutition / Q000502:physiology*; D049631:Esophageal Sphincter, Upper / Q000502:physiology; D005260:Female; D006801:Humans; D007013:Hypopharynx / Q000502:physiology; D008297:Male; D008365:Manometry / Q000379:methods; D008875:Middle Aged; D009824:Ointments; D010614:Pharynx / Q000502:physiology*; D012996:Solutions; D014867:Water; D055815:Young Adult
chemical_list: D009824:Ointments; D012996:Solutions; D014867:Water
keywords: Bolus volume; Deglutition; High-resolution manometry; Swallowing physiology