A method of using cavitate- or clathrate-forming host/guest complexes for the preparation of contrast media in ultrasonic examination is provided. The host/guest complexes have a host which dissolves in a liquid carrier, releasing the guest (inert gas). With such contrast media, it is possible to...http://www.google.com.au/patents/US5730954?utm_source=gb-gplus-sharePatent US5730954 - Preparation comprising cavitate- or clathrate-forming host/guest complexes as contrast agent 
