Magnetic marker monitoring of esophageal, gastric and duodenal transit of non-disintegrating capsules.

The purpose of the study was to investigate in detail the esophageal, gastric and duodenal passage of non-disintegrating capsules in a fasted, healthy volunteer using Magnetic Marker Monitoring (MMM). Five independent experiments were performed. In each case the same healthy male volunteer ingested one magnetically marked capsule after fasting for at least 8 h. The magnetic dipole fields of the capsules were recorded by biomagnetic multichannel measuring equipment. The positions of the capsules were calculated from the recorded data by methods established in magnetic source imaging. The esophageal, gastric and duodenal passages of the capsules were successfully reconstructed from all recorded data sets. The spatial resolution of the capsules' three-dimensional positions in the organs of the gastrointestinal tract was within a range of several millimeters, with a chosen temporal resolution of up to four milliseconds. The esophageal transit times were between 3-13 s, the gastric residence times were between 14-133 min and the duodenal transit times were between 7-245 s. The data demonstrate that Magnetic Marker Monitoring permits the detailed investigation of the gastrointestinal transit of solids.