Experimental Study of the Stability of SonazoidTM

「ABSTRACT」「Purpose」: The purpose of this study was to evaluate the physical characteristics of SonazoidTM and its stability in comparison with LevovistTM and to clarify its usefulness for producing enhancement effects in superficial areas. 「Materials and Methods」: We evaluated changes in particle-size distribution over time. We also examined the stability of SonazoidTM during ultrasound examination using the B mode and the harmonic imaging method. In addition, we observed changes in each contrast agent flowing through the lumen of a tissue-equivalent phantom. 「Results」: Differential interference optical microscopy revealed microbubbles that were uniform in size (1-2 μm) and dispersal pattern. No changes in the particle size distribution were observed 150 minutes after preparation. The density of microbubbles tended to decrease over time. Microbubbles of SonazoidTM were more readily destroyed than were those of LevovistTM, both when ultrasound beams with a low mechanical index value were directly applied to the contrast agent solution and when they were applied to the phantom containing contrast medium. 「Conclusion」: The results of our experiments suggest the usefulness of the enhancement effects of SonazoidTM on superficial organs. On the other hand, LevovistTM, a first-generation contrast agent, has no enhancement effects on these organs.