The purpose of this article was to determine whether applying negative or positive pressure to perfluorocarbon-containing microbubbles before intravenous injection would improve the myocardial contrast when using newer imaging techniques such as harmonic and intermittent imaging. Perfluorocarbon-containing microbubbles were exposed to sustained negative or positive pressure before intravenous injection in 10 dogs. Microbubble size distribution and concentration were measured after each exposure. Peak myocardial video-intensity with intermittent harmonic imaging with each sample was compared. Microbubbles exposed to -200 mm Hg pressure before intravenous injection produced both the highest concentration of micro-bubbles and greater numbers of microbubbles less than 4 μm. Peak myocardial videointensity did not correlate with microbubble concentration or size but did correlate with the absolute number of microbubbles <4 μm (mean r value 0.76, range 0.61 to 0.90). Risk area was best visualized with perfluorocarbon-containing microbubble samples containing the smallest microbubbles. We conclude that the myocardial contrast observed with perfluorocarbon-containing microbubbles can be enhanced by applying negative pressure before injection. The mechanism for this improved contrast appears to be related to creation of smaller microbubbles.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of the American Society of Echocardiography|
|State||Published - 1997|
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Cardiology and Cardiovascular Medicine