[Contrast echocardiology in two dimensions and in real time. 1. Ultrasonic techniques]

An aqueous solution (5% glucose) injected rapidly into a peripheral vein modifies the acoustic homogeneity of the blood not only at the periphery, but also within the cavities of the heart. This ultrasonic contrast technique has taken a new lease of life thanks of two-dimensional echocardiology in real time, which allows the blood to be visualised as it moves. A description is given of the current two-dimensional real time transducers, and the dynamically focal multiscan which has been developed in our laboratories. An analysis is made of the chosen ultrasonic contrast medium (glucose water), of the site and mode of injection, of the recording technique and of the various echocardiological views. Finally, a discussion highlights the limitations of single crystal echocardiography, and the advantages of the two-dimensional technique in real time.