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.
Pregnancy test
Obstetric ultrasonography may also be used to detect pregnancy. Obstetric ultrasonography was first practiced in the 1960s; the first home test kit for hCG was invented in 1968. The kits went on the market in the United States and Europe in the mid-1970s.