Abstract
Chronic constipation and gastrointestinal motility disorders constitute a large part of a gastroenterology practice and represent a significant impact on patient quality of life and lifestyle. In most cases, medications are prescribed to alleviate symptoms without an objective measurement of response. Commonly used current investigations of gastrointestinal transit times are limited to radiopaque markers or electronic capsules. Repeated use of these techniques is limited due to radiation exposure or the significant cost of the devices. We present the proof of concept of a new device to measure the gastrointestinal transit time using commonly available and inexpensive materials with only a small amount of radiotracer. Methods: A gelatin capsule containing paraffin and radiolabeled rice was assembled using 67Ga-citrate as the tracer material. This point source transit device (PSTD) was tested for stability in-vitro and subsequently given to 4 normal volunteers and 10 patients with symptoms of constipation or diarrhea. Imaging was performed at regular intervals until the PSTD was excreted. Results: The PSTD remained intact and visible as a point source in all subjects until excretion. Used in combination with a diary of bowel movement times and dates, the total transit time could be determined. The PSTD could be visualized either alone, in combination with a barium small bowel follow through study, or in conjunction with a gastric emptying study. Conclusion: The use of a PSTD for the determination of GI transit time is a feasible alternative to other methods. The PSTD is inexpensive, easy to assemble, requires only a small amount of radiotracer and remains inert through the GI tract allowing for accurate determination of gastrointestinal transit time. Further investigation with this device is required to establish optimum imaging parameters and normal values. The use of gastrointestinal transit time measurements may be useful in the management of patients with dysmotility and to help select the appropriate pharmaceutical management.