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.
Ultrasonography of chronic venous insufficiency of the legs
From the 1960s commercially available systems were introduced. Soon, other advances in electronics and piezoelectric materials enabled further improvements which meant that ultrasound was quickly adopted for use in medicine due to its rapid, accurate diagnostic capabilities which offered the possibility of prompt treatment. Alongside the improving imaging technology, acoustic Doppler velocimetry and medical ultrasonography color Doppler were developed, which have had a significant impact on many specialties, including radiology, obstetrics, gynecology, angiology and cardiology, and have provided even greater scope for ultrasound investigations. Since 1970, real-time scanners and pulsed Doppler, have enabled the use of ultrasound to study the function of the venous system. The first demonstration of color Doppler was achieved by Geoff Stevenson.
Further progress in the 1970s was made with the arrival of the microchip, and the ensuing exponential increase in processing power has meant the development of fast and powerful systems. These systems involving digital beamforming and greater signal enhancement, have introduced new methods of interpreting and displaying data.