title: Functional lumen imaging of the gastrointestinal tract.
abstract: This nonsystematic review aims to describe recent developments in the use of functional lumen imaging in the gastrointestinal tract stimulated by the introduction of the functional lumen imaging probe. When ingested food in liquid and solid form is transported along the gastrointestinal tract, sphincters provide an important role in the flow and control of these contents. Inadequate function of sphincters is the basis of many gastrointestinal diseases. Despite this, traditional methods of sphincter diagnosis and measurement such as fluoroscopy, manometry, and the barostat are limited in what they can tell us. It has long been thought that measurement of sphincter function through resistance to distension is a better approach, now more commonly known as distensibility testing. The functional lumen imaging probe is the first medical measurement device that purports in a practical way to provide geometric profiling and measurement of distensibility in sphincters. With use of impedance planimetry, an axial series of cross-sectional areas and pressure in a catheter-mounted allantoid bag are used for the calculation of distensibility parameters. The technique has been trialed in many valvular areas of the gastrointestinal tract, including the upper esophageal sphincter, the esophagogastric junction, and the anorectal region. It has shown potential in the biomechanical assessment of sphincter function and characterization of swallowing disorders, gastroesophageal reflux disease, eosinophilic esophagitis, achalasia, and fecal incontinence. From this early work, the functional lumen imaging technique has the potential to contribute to a better and more physiological understanding of narrowing regions in the gastrointestinal tract in general and sphincters in particular.
authors.affiliation: Mech-Sense, Department of Gastroenterology and Hepatology, Aalborg University Hospital, Aalborg, Denmark. chlo@rn.dk.
authors.forename: Christian
authors.initials: C
authors.lastname: Lottrup
authors.affiliation: GIOME and the Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, 83 Shabei Lu, 400044, Chongqing, China. hag@giome.org.
authors.forename: Hans
authors.initials: H
authors.lastname: Gregersen
authors.affiliation: GIOME Academia, Department of Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Donghua
authors.initials: D
authors.lastname: Liao
authors.affiliation: Neurogastroenterology Unit, Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Lotte
authors.initials: L
authors.lastname: Fynne
authors.affiliation: Mech-Sense, Department of Radiology, Aalborg University Hospital, Aalborg, Denmark.|Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.
authors.forename: Jens Brøndum
authors.initials: JB
authors.lastname: Frøkjær
authors.affiliation: Neurogastroenterology Unit, Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Klaus
authors.initials: K
authors.lastname: Krogh
authors.affiliation: Trinity Academic Gastroenterology Group, Tallaght Hospital, Dublin, Ireland.
authors.forename: Julie
authors.initials: J
authors.lastname: Regan
authors.affiliation: Mech-Sense, Department of Gastroenterology and Hepatology, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Kunwald
authors.affiliation: GIOME and the Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, 83 Shabei Lu, 400044, Chongqing, China.|Trinity Academic Gastroenterology Group, Tallaght Hospital, Dublin, Ireland.
authors.forename: Barry P
authors.initials: BP
authors.lastname: McMahon
mesh_terms: D003952:Diagnostic Imaging / Q000379:methods*; D004943:Esophagogastric Junction; D005767:Gastrointestinal Diseases / Q000175:diagnosis*; D006801:Humans
keywords: Functional lumen imaging probe; Gastrointestinal sphincters; Geometric profiling