A portable and very inexpensive optical-fiber sensor for entero-gastric reflux detection

A very compact and easily-transportable optical-fiber sensor for 'in vivo' detection of bile reflux from the duodenum into the stomach (entero-gastric reflux) has been developed. It makes use of two light-emitting diodes (for signal and reference, respectively) and of a special electronic circuit which processes the signals and provides the readout on a display. Quartz and plastic fiber bundles are used and compared in order to obtain the best solution in terms of signal levels and price. A suitable probe was specially designed and made finalized for 'in vivo' measurements. Measurements with the optical sensor were performed on several patients. A comparison with the traditional indirect method of detection, based on a change in acidity inside the stomach, showed the eminently greater suitability of the optical sensor for detection of entero-gastric reflux.