Detection of individual microbubbles of ultrasound contrast agents: imaging of free-floating and targeted bubbles.

Rationale And Objectives: During echo examinations with microbubble contrast, individual "dots" of ultrasound reflection can be visualized. To address the question whether these signals represent individual microbubbles, very dilute suspensions of ultrasound contrast agents or individual microbubbles attached to Petri dishes were prepared and studied by ultrasound imaging.

Methods: Microbubble suspensions were diluted in saline and evaluated by a clinical ultrasound imaging system.