Imaging reflux

Abstract

Diagnostic imaging methods allow evaluating morphology and function of the upper gastrointestinal tract and have been used to evaluate reflux and its complications. In this chapter the main whole-body imaging techniques used to image reflux are described briefly, including their advantages and limitations. X-ray and video fluoroscopy in conjunction with oral barium contrast media can document reflux and a range of morphological changes such as hiatal hernia. Whist X-ray methods are well established, generally available and relatively cheap, they involve giving a dose of ionizing radiation to the patients. Nuclear medicine techniques exploit the sensitivity to small amounts of radiolabels to form images that can evaluate gastroesophageal reflux disease. This sensitivity allows demonstrating postprandial pulmonary aspiration of the ingested radiolabel by showing increased counts in the lung fields. Two and three dimensional nuclear medicine techniques used to image lung delivery of inhaled pharmacological agents could provide a promising technology to investigate airway reflux. More recently a role for MRI has emerged. MRI fluoroscopy is capable to image directly reflux, swallowing and bolus passage in the esophagus. MRI has the advantages of using non ionizing radiation, multi-planar capability, good spatial resolution and good soft tissue contrast. Sensitivity however is low.