Scintigraphic Measurement of Regional Colonic Transit Time in Healthy Controls

Choi, Suck Chei; Kim, Jae Hyung; Hwang, Ho Geun; Yang, Sei Hoon; Kim, Jin Ah; Nah, Yong Ho; Lee, Choon Ho; Kim, Chang Guhn

Abstract

BACKGROUND/AIMS: Measurements of regional transit are highly relevant to an understanding of normal colonic function and of any derangements associated with disease. Currently available clinical tests of colonic transit, such as the radiopaque marker method, are useful in detecting delayed transit but may be less sensitive for rapid transit. Our aim was to develop a method whereby the transit of solid residue measvred unprepared human colon.
METHODS
We used a noninvasive method to label the solid phase of contents in the unprepared human colon. "Indium-labeled Amberlite IR-120 beads(Siga Chemica] Co.) were placed in a gelIatin capsule which was then coated with methacrylate. When ingested by healthy controls, capsules released radiolabeled beads in the dista] ileum or proximal colon in 22 of 22 controls. Transit of "Indium-pellets through the unprepared colon could be quantitated radioscintigraphically.
RESULTS
Emptying of the ascending colon was characterized by an initial lag period(112.50+/-80.75 min, mean +/- S.D). Mean colonic transit times were measured using both the radiopaque markers and radioscintigraphy. The mean colonic transit times were 1212.50+/-413.98min (rnean < S.D) in radioscintigraphy, and 1014.40+/-631.67min(mean +/- S.D) in radiopaque marker. So there was a good correlation(r=0.7) between radioisotope method and radiopaque marker method. Radioactivity counts were distributed equally between ascending colon, transverse colon, descending colon, and rectosigmoid colon at the 12th hour. Geometric center analysis showed an initial progression of activity in the proximal colon and a linear progression distally.
CONCLUSIONS
Colonic scintigraphy is a safe and quantitative method for evaluating the colonic transit of fecal material and may provide a usefu] tool for evaluating large intestinal physiology. In healtby adults, normal orol-cecal transit time is about 5 hours and normal colonic transit time is about 24 hours when using radioscintigraphic method.