title: Automated production and analysis of echo contrast agents.
abstract: To develop and standardize contrast agents for use in contrast echocardiographic imaging, microbubble size, concentration, decay, and ultrasound backscatter must be known. These parameters were assessed with a scanning laser particle counter, a commercial ultrasound unit, and various sonicated intravenous solutions. The scanning laser particle counter proved to be a fast and effective means of evaluating microbubble size, concentration, and stability. In addition, sonication was found to be a reliable and reproducible technique for preparing standardized echo contrast agent solutions containing uniformly small microbubbles. The bubbles generated ranged in size from 1 to 15 micron in diameter. All solutions had mean bubble diameters less than 6 micron. The half life of solutions ranged from 44 +/- 12 seconds for Hypaque 50%, to 253 +/- 73 seconds for Iopamidol. Addition of the surfactant to dextrose 70% prolonged bubble half life from 58 +/- 12 seconds to 1018 +/- 276 seconds. Phased array two-dimensional echocardiography of sonicated microbubble solutions, and subsequent videodensitometric analysis, revealed that bubble concentration was directly proportional to echo-reflective properties, and that the solutions have significant ultrasound reflective properties in vitro at concentrations of less than 1500 bubbles/ml.
mesh_terms: D001322:Autoanalysis; D001331:Automation; D003287:Contrast Media / Q000032:analysis*; D005947:Glucose / Q000378:metabolism; D006801:Humans; D010316:Particle Size; D012542:Scattering, Radiation; D014465:Ultrasonics
chemical_list: D003287:Contrast Media; D005947:Glucose