Medical ultrasound
A contrast medium for medical ultrasonography is a formulation of encapsulated gaseous microbubbles to increase echogenicity of blood, discovered by Dr Raymond Gramiak in 1968 and named contrast-enhanced ultrasound. This contrast medical imaging modality is clinically used throughout the world, in particular for echocardiography in the United States and for ultrasound radiology in Europe and Asia.
Medical ultrasound
Microbubbles-based contrast media is administrated intravenously in patient blood stream during the medical ultrasonography examination. Thanks to their size, the microbubbles remain confined in blood vessels without extravasating towards the interstitial fluid. An ultrasound contrast media is therefore purely intravascular, making it an ideal agent to image organ microvascularization for diagnostic purposes. A typical clinical use of contrast ultrasonography is detection of a hypervascular metastatic tumor, which exhibits a contrast uptake (kinetics of microbubbles concentration in blood circulation) faster than healthy biological tissue surrounding the tumor. Other clinical applications using contrast exist, such as in echocardiography to improve delineation of left ventricle for visually checking contractibility of heart after a myocardial infarction. Finally, applications in quantitative perfusion (relative measurement of blood flow ) emerge for identifying early patient response to an anti-cancerous drug treatment (methodology and clinical study by Dr Nathalie Lassau in 2011), enabling to determine the best oncological therapeutic options.