Scintigraphic study of lipid kinetics after ingestion of a meal labelled with lipiodol-I123

This work is included in a programme concerning the relationships between meal ingestion and lipidemia; its specific aim was to assess by scintigraphy the long term kinetics of orally ingested radiolabelled lipids. Nine healthy volunteers ingested a breakfast that included iodized fatty acid extracted from poppy-seed oil of Lipiodol 1123. The images including thorax and abdomen were repeated for 8 hours. Six of the subjects ingested a single meal (group 1), the three other subjects had a lunch 4 h 30 after the i labelled breakfast (group 2). The analysis included the study of pictures with the determination of organs visualization times and the drawing of time activity curves from these organs ROI's. The chronology of organs appearance was stomach, bowel, thoracic duct, then heart and liver. The study allowed to follow the long term kinetics of the ingested lipids and notably to visualize the thoracic duct. The second meal ingestion was followed by an increase of the thoracic duct activity. These preliminary results suggest that scintigraphy using iodized fatty acids allows to visualize the behavior of the ingested lipids and can help to better understand the variation of lipidemia that is related with the ingestion of meals. They suggest that a part of the ingested fats enters the plasma only after a second meal. (authors)