The patent also covers methods of forming microbubbles containing perfluoropropane
, perfluorobutane, perfluoropentane, perfluoroheptane and other fluorochemicals.
Researchers from The Toronto Hospital and the University of Toronto presenting preliminary clinical trial results at the 84th Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA) showed they were able to overcome a long-standing difficulty with ultrasound in the detection of focal liver masses using Pulse Inversion Harmonics and a perfluoropropane
5,562,893, is titled "Gas-filled Microspheres with Fluorine Containing Shells," and covers ultrasound imaging agents which comprise hydrocarbon and perfluorocarbon gases, such as perfluoropropane
, perfluorobutane, perfluoropentane within fluorine containing shells.
The '751 patent claims are directed to compositions of ultrasound contrast media in which perfluoropropane and perfluorobutane are specified.
Certain claims, directed to fluorinated chemicals other than perfluoropropane, perfluorobutane, and perfluoropentane, were canceled during the re-examination process.
While these PFCs -- halocarbons 116, 14, and 23; sulfur hexafluoride; nitrogen trifluoride; and perfluoropropane
-- are essential to many manufacturing processes, many environmental scientists believe they may last as long as 50,000 years when released into the atmosphere.
The Patent Has Broad Claims Covering Perfluoropropane
The new patent is directed to ultrasound contrast media comprising free gas microbubbles of any fluorine-containing hydrocarbon generally and including certain specific chemicals: perfluoroethane, perfluoropropane
, perfluorobutane, and dodecafluoropentane (DDFP).