Radiographic imaging of the rat tapeworm, Hymenolepis diminuta

The model of Hymenolepis diminuta Rudolphi in laboratory rats was used to i nvestigate potential applications of radiographic imaging in the diagnosis and/or study of tapeworm infections. Radiographic imaging successfully demo nstrated the presence of H. diminuta in the rat intestine in the presence o f a water-soluble iodinated radiographic contrast medium, Gastrografin(R). Even single worms and small segments of proglottids could be detected. Opti mal imaging was achieved with an exposure factor of 3.75 mAs at 54 kVp with mammography film. Visualization was improved by fasting the rat host to ef fect the elimination of food and fecal shadows. Elaboration of this methodo logy may prove useful in basic research and the incidental diagnosis of hum an tapeworm infection by permitting rapid diagnosis of prepatent infection. thereby providing a useful tool in efficacy testing of anthelmintics when assessing prepatent success and temporal aspects of drug activity.