Segmental Colon Transit Time with Radiopaque Markers in a Delayed-release Capsule

Choi, Hwang; Choi, Myung Gyu; Kim, Byung Wook; Kim, Jae Kwang; Han, Sok Won; Choi, Kyu Young; Chung, Kyu Won; Sun, Hee Sik; Park, Doo Ho; Son, Hyung Sun

Abstract

BACKGROUNDS/AIM: Scintigraphic measurement of colon transit has been proven useful clinically and in the research area, however this method requires well equipped laboratories. The aim of this study was to develop a new colon transit test using radiopaque markers instead of radiolabeled pellets in a methacrylate-coated capsule.
METHODS
Ten healthy volunteers were studied. After simultaneous administration of two methacrylate-coated gelatin capsules containing activated charcoal mixed with 8 mCi of 99mTc or a commercially used radiopaque marker, scintigraphies and plain abdominal X-rays were performed. We compared colon transit profiles as the geometric center at 4, 8, 24, and 48 hours after ingestion of gelatin capsules. This new radiopaque marker test was validated with a scintigraphic method as the gold standard.
RESULTS
Geometric centers (mean+/-SEM) of 99mTc-scintigraphy were 0.50+/-0.18 at 4 hours, 1.16+/-0.05 at 8 hours, 3.31+/-0.36 at 24 hours, and 4.16+/-0.29 at 48 hours. Geometric centers of the radiopaque marker method were 0.40+/-0.16, 1.13+/-0.05, 3.33+/-0.37, and 4.18+/-0.30 respectively. Transit profiles were the same with both methods and highly correlated (r=0.994, p < 0.001). The difference between the two methods against the mean for the geometric center was within 2SD.
CONCLUSIONS
A colon transit test using radiopaque markers in a methacrylate-coated, delayed release capsule was inexpensive, simple, and reliable. This new test could be applicable when a gamma camera is not available.