Gastrointestinal scintiscanning: dosimetry

Calculations of the dosimetry associated with orally administered 99mTc labeled cellulose fibres and 111In labeled plastic particles were performed for adult standard man using MIRD methodology. The applied gastrointestinal transit parameters of these radiopharmaceuticals probably reflect the ranges of these parameters, regarding nondigestible components used for gastrointestinal transit studies. However, the critical organ for both radiopharmaceuticals was the large intestine.