This selective review highlights research in contrast media development and
application in the held of diagnostic radiology in 1998 and 1999, The focu
s is on research published in Investigative Radiology, supplemented with wo
rk from other publications in the few areas not extensively covered by the
journal. Studies continue to be performed, although at a low level, examini
ng safety issues. Most preclinical investigations have focused on MR and ul
trasound agents. In MR, the research effort is concentrated on the developm
ent of targeted agents; in ultrasound, work is focused on the characterizat
ion of basic contrast mechanisms. The demonstration of clinical application
s is still dominated by work with MR, both in disease models and human inve
stigations. The use of extracellular gadolinium chelates to enhance visuali
zation of blood vessels (the field of contrast-enhanced MR angiography) is
the largest single new clinical application of contrast media to emerge in
several years. New clinical applications continue to be pursued with contra
st media in CT, ultrasound, and x-ray angiography, As intravenously injecte
d ultrasound contrast agents come to market, trials demonstrating clinical
applications and subsequent scientific publications,will increase in number
.