Encapsulated microbubbles and echogenic liposomes for contrast ultrasound imaging and targeted drug delivery

Micron- to nanometer-sized ultrasound agents, like encapsulated microbubbles and echogenic liposomes, are being developed for diagnostic imaging and ultrasound mediated drug/gene delivery. This review provides an overview of the current state of the art of the mathematical models of the acoustic behavior of ultrasound contrast microbubbles. We also present a review of the in vitro experimental characterization of the acoustic properties of microbubble based contrast agents undertaken in our laboratory. The hierarchical two-pronged approach of modeling contrast agents we developed is demonstrated for a lipid coated (Sonazoid TM ) and a polymer shelled (poly D-L -lactic acid) contrast microbubbles. The acoustic and drug release properties of the newly developed echogenic liposomes are discussed for their use as simultaneous imaging and drug/gene delivery agents. Although echogenicity is conclusively demonstrated in experiments, its physical mechanisms remain uncertain. Addressing questions raised here will accelerate further development and eventual clinical approval of these novel technologies. � Read more... Abstract: Micron- to nanometer-sized ultrasound agents, like encapsulated microbubbles and echogenic liposomes, are being developed for diagnostic imaging and ultrasound mediated drug/gene delivery. This review provides an overview of the current state of the art of the mathematical models of the acoustic behavior of ultrasound contrast microbubbles. We also present a review of the in vitro experimental characterization of the acoustic properties of microbubble based contrast agents undertaken in our laboratory. The hierarchical two-pronged approach of modeling contrast agents we developed is demonstrated for a lipid coated (Sonazoid TM ) and a polymer shelled (poly D-L -lactic acid) contrast microbubbles. The acoustic and drug release properties of the newly developed echogenic liposomes are discussed for their use as simultaneous imaging and drug/gene delivery agents. Although echogenicity is conclusively demonstrated in experiments, its physical mechanisms remain uncertain. Addressing questions raised here will accelerate further development and eventual clinical approval of these novel technologies Ultrasound imaging is one of the most important and widely used diagnostic tools in modern medicine, second only to the conventional x-ray. Although considered a mature field, research continues for improving the capabilities and finding new uses for ultrasound technology while driving down the cost of newer, more complicated procedures such as intravascular ultrasound. Diagnostic Ultrasound: Imaging and Blood Flow Measurements presents new developments, fundamental physics, instrumentation, system architecture, biological effects of ultrasound, and clinical applications that reflect this init "This is a substantial revision of a respected work that details the latest advances in ultrasound technology related to biomedical applications. This includes such topics as elastrography, portable scanners, ultrasound molecular imaging, preclinical high frequency imaging, 2D array and 4D imaging techniques. Each chapter has been considerably updated and expanded. A new chapter has been added on new developments such as elastography and minature scanners. New case studies and examples throughout the book are also included in this new edition"-- Provided by publisher Offers an Extensive Discussion on High Frequency UltrasoundBased on a course taught and developed by a foremost expert in diagnostic ultrasound technology, Diagnostic Ultrasound: Imaging and Blood Flow Measurements, Second Edition covers cutting-edge developments, along with the fundamental physics, instrumentation, system architecture, clinical ap "Emphasizing the engineering and signal processing aspects of ultrasound technology rather than taking a clinical perspective. Diagnostic Ultrasound: Imaging and Blood Flow Measurements encourages and enables further advances in this established yet dynamic field." --Book Jacket.