Ultrasound contrast agents: clinical applications.

Ultrasound contrast agents (USCA) for intravenous injections are usually gas-filled microbubbles with a mean diameter less than that of a red blood corpuscle. There are only a few products on the market at the time of this writing, but several companies have various agents under development. This paper covers both established USCA on the market, and some new agents under clinical evaluation. The potential of improving ultrasound imaging using USCA depends on several factors. These factors include the pharmacokinetic and pharmacodynamic properties of the products, which determine the effects they have on various ultrasound imaging techniques. Furthermore, the proper clinical application of the agents requires a combination of technical and medical knowledge by the examiner, dedicated equipment, a disease that can be diagnosed or characterised by ultrasound and USCA, and a cooperative patient. Taking into account these factors, USCA can be used for improving the detection, characterisation and follow-up of diseases of several vascular beds and parenchymal organs from head to foot.