Increased ultrasound contrast and decreased microbubble destruction rates with triggered ultrasound imaging.

摘要: Although transient myocardial contrast imaging has been able to produce visually evident in animals and humans with very low intravenous doses of perfluorocarbon-exposed sonicated dextrose albumin (PESDA) microbubbles, the mechanism for improved remains unclear. In this study we devised a flow chamber that measured concentration PESDA microbubbles remained after exposure diagnostic ultrasound pressures 0.9 1.9 MPa frequencies 2.0, 2.5, 3.5 MHz (first second harmonic 2.0 MHz), which were delivered at either 30 Hz (frames per second), 0.5 1.0 Hz, or without any transmission. The videointensity within was also 0, 20, 40, 100 ml/min rates loop closed (i.e., constant microbubble concentration) both triggered (0.5 Hz) conventional (30 frame rates. effluent significantly larger when exposed no ultrasound. Furthermore, number greater (triggered) compared (conventional) each transmit frequency. greatest difference noted lower frequency 20 rate, especially receiving used. We conclude is because less destruction increased from microbubbles. Lower transducer result improvement