Colonic movements in healthy subjects as monitored by a Magnet Tracking System

Abstract

The Magnet Tracking System (MTS) is a minimally-invasive technique of continuous evaluation of gastrointestinal motility. In this study, MTS was used to analyse colonic propulsive dynamics and compare the transit of a magnetic pill with that of standard radio-opaque markers. MTS monitors the progress in real time of a magnetic pill through the gut. Ten men and 10 women with regular daily bowel movements swallowed this pill and 10 radio-opaque markers at 8 pm. Five hours of recordings were conducted during 2 following mornings. Origin, direction, amplitude and velocity of movements were analysed relative to space-time plots of the pill trajectory. Abdominal radiographs were taken to compare the progress of both pill and markers. The magnetic pill lay idle for 90% of its sojourn in the colon; its total retrograde displacement accounted for only 20% of its overall movement. Analysis of these movements showed a bimodal distribution of velocities: around 1.5 and 50 cm min(-1), the latter being responsible for 2/3 of distance traversed. There were more movements overall and more mass movements in males. Net hourly forward progress was greater in the left than right colon, and greater in males. The position of the magnetic pill correlated well with the advancement of markers. MTS showed patterns and propulsion dynamics of colonic segments with as yet unmet precision. Detailed analysis of slow and fast patterns of colonic progress makes it possible to specify the motility of colonic segments, and any variability in gender. Such analysis opens up promising avenues in studies of motility disorders.

Colorectal Transit and Volume During Treatment With Prolonged-release Oxycodone/Naloxone Versus Oxycodone Plus Macrogol 3350

“…15 In short, the 3D-Transit system is a minimally invasive, ambulatory system, which relies on small, wireless telemetric capsules that are ingested and an extracorporeal, portable detector that tracks the precise position and general orientation of the capsule from ingestion to expulsion. 16,17 Accordingly, changes in position, velocity of movements, and orientation of the capsules, reflecting gut contractile activity, and progression dynamics, may be Questionnaires studied with respect to anatomical information. 16,18 Segmental transit times of the colon (cecum/ascending colon, transverse colon, descending colon, and rectosigmoid colon) were evaluated based on visualization and determination of the trajectory transversed in the colon by the 3D-Transit capsule, as described previously.…”

Understanding gastric forces calculated from high-resolution pill tracking

“…The tracking system consists of a pill containing a permanent magnet, a detection matrix (4 · 4 magnetic field sensors) and dedicated software implanted in a laptop computer (MTS-1, Motilis) (18). The tracking algorithm calculates the position and the orientation of the pill at 10 Hz, except the rotation around the magnetization axis (i.e., five degrees of freedom, three translations, and two rotations).…”

“…Additionally, pill-tracking methods have primarily been used to determine gastrointestinal tract residence time. Recently, our group and others have reported measurements using inexpensive, highly accurate real-time magnetic tracking (17)(18)(19)(20). We employed a Hall array sensor technology to inexpensively and noninvasively track the position and orientation of magnetic model pills within the stomachs of humans, rats, and dogs without anesthesia.…”

Regional Gastrointestinal Transit Times in Patients With Carcinoid Diarrhea: Assessment With the Novel 3D-Transit System

“…18 In addition to the information about transit times provided by the WMC, 3D-Transit may allow assessment of regional colonic transit times and, as shown in the present paper, the system holds promise for description of single pansegmental movements within the colon. The data analysis program for 3D-Transit is still in its infancy, but previous studies with MTS-1 allowed description of colonic mass movements, 23,24 velocity through the different parts of the GI tract, 15,20,[25][26][27][28][29][30] retrograde movements, 23 and a gastric motility index. Our previous studies based on the tracking of a permanent pill were much hampered by the stationary nature of the system, which necessitated the person to sit still in a non-magnetic bed.…”