An experimental model for the detection and localisation of gastrointestinal bleeding using 99mTc-DTPA.

99mTc-DTPA was successfully used to detect simultaneously gastrointestinal bleeding sites in experimentally created mucosal ulcers in the colon and stomach of rabbits. Unlike the other radiopharmaceuticals that are currently used, 99mTc-DTPA was rapidly cleared from the vascular, hepatic and splenic circulation. The overall background radioactivity was low. 99mTc-DTPA appears to be an ideal agent for detection and localisation of gastrointestinal bleeding sites.