Nycomed patent holds promise of creating x-ray and ultrasound agent

A commercial product is a long way off, however

It could be a formidable product: a contrast agent opaque to x-rays and reflective of ultrasound. A dual-purpose product of this type is possible-at least, theoretically-and Nycomed Amersham of Buckinghamshire, U.K., has the patent. But whether a product will ever be developed is not certain.

The U.S. Patent and Trademark Office awarded Nycomed Amersham a patent for such a technology in June, according to Nycomed research scientist Arne Berg, the lead inventor cited on the patent. The patent covers the use of conventional x-ray agents that can be agitated, or sonicated, to form a matrix or honeycomb of gas-filled voids. Nycomed scientists have determined that these agents, when agitated to incorporate gas bubbles, can substantially enhance contrast in ultrasound studies. The patent specifically cited echocardiography as one such application.

The radiopaque properties inherent in the agents and their echogenicity would provide, in essence, a dual-purpose product. But developing such an agent as a viable commercial product would be far more difficult than earning a patent for the technology.

"I think it is difficult to think of a dual agent that would have high efficacy in ultrasound and high efficacy in x-ray," Berg said.

Companies sometimes stake out turf with patents, filing applications for ideas that might be developed. Whether they are developed depends partly on the market and partly on other products in the pipeline. The patent awarded in June to Nycomed Amersham may represent one of these instances.

"In the early phase of exploring all the possibilities, you try to cover as much (ground) as possible. Agitated x-ray contrast was one of the first ultrasound contrast media, because it forms gas pockets and actually has been used for that purpose," Berg said. "It is not a product line that is worked up."

Holding the patent, however, keeps the door open for Nycomed. Should the company choose to pursue such a route, and if engineers are able to optimize such an agent for two purposes, Nycomed could have an agent with extraordinary customer appeal.