title: Proposed Use of Thickener According to Fluid Intake on Videofluoroscopic Swallowing Studies: Preliminary Study in Normal Healthy Persons.
abstract: OBJECTIVE
  To examine the characteristics and changes in the pharyngeal phase of swallowing according to fluid viscosity in normal healthy persons, to help determine fluid intake methods in more detail than the use of standardized fluid.
  
  
  METHODS
  This was a prospective observational study involving 10 normal healthy adults. While the participants sequentially took in fluids with 10 different viscosities changes in the pharyngeal phase of the swallowing process were monitored using videofluoroscopic swallowing studies (VFSS). Twenty parameters of the pharyngeal phase, including epiglottis contact, laryngeal elevation, pharyngeal constriction, and upper esophageal sphincter opening, were determined and compared.
  
  
  RESULTS
  No significant viscosity-based changes in epiglottis contact, laryngeal elevation, or upper esophageal sphincter-opening duration of the pharyngeal phase were observed. However, pharyngeal transit time and time from the start of the pharyngeal phase to peak pharyngeal constriction were significantly delayed upon intake of fluid with viscosities of 150.0 centipoise (cP) and 200.0 cP.
  
  
  CONCLUSIONS
  VFSS analysis of fluid intake may require the use of fluids of various concentrations to determine a suitable viscosity of thickener mixture for each subject.
authors.affiliation: Department of Rehabilitation Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Kyung Duck
authors.initials: KD
authors.lastname: Lee
authors.affiliation: Department of Rehabilitation Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Sun Hong
authors.initials: SH
authors.lastname: Song
authors.affiliation: Department of Rehabilitation Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Jung Hoi
authors.initials: JH
authors.lastname: Koo
authors.affiliation: Department of Rehabilitation Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Hee Seon
authors.initials: HS
authors.lastname: Park
authors.affiliation: Department of Rehabilitation Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Jae Sin
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Food & Nutrition, College of Health & Welfare, Kangwon National University, Samcheok, Korea.
authors.forename: Ki Hyo
authors.initials: KH
authors.lastname: Jang
keywords: Dysphagia; Thickener; Viscosity