Balloon-distension studies in the gastrointestinal tract: current role.

Balloon distension is a commonly used technique in visceral organs. Research studies take advantage of this technique for studying organ physiology, e.g. for studying the force-deformation relationship and mechanosensitive receptors in the gastrointestinal wall. Balloon distension is also used for diagnostic purposes, e.g. in the diagnostics of non-cardiac chest pain and for treatment of diseases such as bleeding esophageal varices caused by liver disease and lower esophageal sphincter occlusion caused by achalasia. Balloon distension can be carried out with concomitant measurements of pressure, volume and cross-sectional area alone or in combination. Furthermore, balloon-distension techniques can be combined with various imaging techniques such as B-mode ultrasonography and MRI to obtain three-dimensional geometric data about the three-dimensional surface with subsequent calculation of the tension or stress in the gastrointestinal organs. This article describes balloon-distension techniques, in particular new developments of the impedance planimetric technique including methods for studying gastrointestinal muscle function.