Sonicated echocardiographic contrast agents: reproducibility studies.

This article describes the production, analysis, and reproducibility of forming microbubbles for contrast ultrasound imaging. The sonication method used to generate microbubbles was tested by four independent observers, and a subsequent laser particle counter analysis of microbubble size and concentration determined the reproducibility of the method. The results indicated that the mean bubble size was 3.3 +/- 1.2 microns for the entire group, based on three trials of each of the four participants. The characteristics of the bubble size of the microbubbles between observers were assessed with a Poisson distribution with the reproducibility based on the sample mean for each observer's trials. Standardization and calibration of the laser particle counter was accomplished with commercially available latex spheres, sonicated albumin microspheres, and a Coulter counter analysis. Our results indicate that the sonication technique generates small microbubbles with a reproducible uniform size distribution. The method of microbubble production is reproducible and can be widely applied for use in contrast echocardiographic perfusion imaging of tissue in a variety of research and clinical studies.