To provide a method of ultrasonic harmonic imaging, enhanced in contrast properties useful for angiography, and to provide a contrast improving agent.
This contrast medium contains microbubbles containing a gaseous substance, for example, a hydrocarbon or a fluorocarbon, which has a form of a spherical film and further has a vapor pressure of more than 23 Torr at 37°C, a solubility/miscibility in water of less than about 1 wt%, a concentration in a molar fraction of more than 2% in a gas phase, when detected, and a concentration of more than 50% based on a saturation concentration thereof. The contrast medium is introduced into a target or body to be imaged. The method of the ultrasonic harmonic imaging comprises using ultrasonic energy which is transmitted to the target or body to be imaged from an ultrasonic source, wherein the method includes subjecting at least a part of the target or body to the ultrasonic imaging.
Hidemi Matsukura
Tsutomu Toyama