[In vitro studies on the development of a high-density contrast medium for double contrast of the colon]

Investigations with an electron microscope and phantom imaging studies showed, that from micro-particle barium sulphate a high-density contrast medium can be produced for double-contrast-investigations of the colon. As stabilizing agent a substance with the same physical and chemical action as 0.6 g CMC (Sodium-Carboxy-Methyl-Cellulose) per 100 g barium sulphate should be used. With a second stabilizer, having the same effect as mixed pectin, the thickness of the contrast film can be modified, while the flow time of the contrast medium remains constant. Flow curves lead to the conclusion, that a maximum concentration of 140 GV% can be used for patients. The measurement of density and flow time of the suspension allow to check the high density and low viscosity requirements. The density of the barium sulphates used for investigation was 4,000 g/l.