title: Utilizing functional lumen imaging probe topography to evaluate esophageal contractility during volumetric distention: a pilot study.
abstract: BACKGROUND
  The functional lumen imaging probe (FLIP) measures luminal cross-sectional area and pressure during volumetric distension. By applying novel customized software to produce FLIP topography plots, organized esophageal contractility can be visualized and analyzed. We aimed to describe the stimulus thresholds and contractile characteristics for distension-induced esophageal body contractility using FLIP topography in normal controls.
  
  
  METHODS
  Ten healthy controls were evaluated during endoscopy with FLIP. During stepwise bag distension, simultaneous intra-bag pressure and luminal diameter measurements were obtained and exported to a MatLab program to generate FLIP topography plots. The distension volume, intra-bag pressure, and maximum esophageal body diameters were measured for the onset and cessation of repetitive antegrade contractions (RACs). Contraction duration, interval, magnitude, and velocity were measured at 8 and 3-cm proximal to the esophagogastric junction.
  
  
  RESULTS
  Eight of ten subjects demonstrated RACs at a median onset volume of 29 mL (IQR: 25-38.8), median intra-bag pressure of 10.7 mmHg (IQR: 8.6-15.9), and median maximum esophageal body diameter of 18.5 mm (IQR: 17.5-19.6). Cessation of RACs occurred prior to completion of the distension protocol in three of the eight subjects exhibiting RACs. Values of the RAC-associated contractile metrics were also generated to characterize these events.
  
  
  CONCLUSIONS
  Distension-induced esophageal contractions can be assessed utilizing FLIP topography. RACs are a common finding in asymptomatic controls in response to volume distention and have similar characteristics to secondary peristalsis and repetitive rapid swallows.
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Carlson
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Rogers
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: C Y
authors.initials: CY
authors.lastname: Lin
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Kahrilas
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Pandolfino
mesh_terms: D000328:Adult; D004943:Esophagogastric Junction / Q000502:physiology*; D004947:Esophagus / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D010528:Peristalsis / Q000502:physiology*; D010865:Pilot Projects; D055815:Young Adult
keywords: esophageal motility; functional lumen imaging probe; impedance planimetry; secondary peristalsis