Claims for Patent: 5,558,094

Summary for Patent: 5,558,094

Title:	Methods for using persistent gases as ultrasound contrast media
Abstract:	Disclosed herein are agents for enhancing the contrast in an ultrasound image. These agents are extremely small bubbles, or "microbubbles," comprised of specially selected gases. The microbubbles described herein exhibit long life spans in solution and may be produced at a size small enough to traverse the lungs, thus enabling improved ultrasound imaging of the cardiovascular system and other vital organs. Also disclosed herein is a method for selecting gases from which contrast agents may be produced. The method is based on calculations using inherent physical properties of gases and describes a means to associate the properties of a gas with the time for dissolution of microbubbles comprised of the gas.
Inventor(s):	Quay; Steven M. (Pacific Palisades, CA)
Assignee:	Sonus Pharmaceuticals, Inc. (Bothell, WA)
Application Number:	08/382,253
Patent Claims:	1. A method of ultrasound imaging comprising the steps of: introducing a collection of free gas microbubbles of a biocompatible chemical into an animal, said chemical having a Q coefficient greater than 30 where Q is the ratio of the persistence of microbubbles of said gas in an aqueous solution to the persistence of microbubbles of air in said solution; and performing an ultrasound scan on said animal. 2. The method of claim 1 wherein the chemical is hexafluoropropylene. 3. The method of claim 1 wherein the chemical is octafluoropropane. 4. The method of claim 1 wherein the chemical is hexafluoroethane. 5. The method of claim 1 wherein the chemical is octafluoro-2-butene. 6. The method of claim 1 wherein the chemical is hexafluoro-2-butyne. 7. The method of claim 1 wherein the chemical is hexafluorobuta-1,3-diene. 8. The method of claim 1 wherein the chemical is octafluorocyclobutane. 9. The method of claim 1 wherein the chemical is decafluorobutane. 10. The method of claim 1 wherein the chemical is dodecafluoropentane. 11. The method of claim 1 wherein said chemical is fluorine containing. 12. The method of claim 1 wherein said chemical is a perfluorocarbon. 13. A method of ultrasound imaging comprising the steps of: introducing a collection of microbubbles of a biocompatible chemical into an animal, where said chemical is selected from the group consisting of hexafluoropropylene, octafluoropropane, octafluoro-2-butene, hexafluoro-2-butyne, hexafluorobuta-1,3-diene, octafluorocyclobutane, decafluorobutane and dodecafluoropentane; and performing an ultrasound scan on said animal. 14. A method of ultrasound imaging comprising the steps of preparing a dispersion of a biocompatible chemical in an aqueous solution, said chemical having a Q coefficient greater than 30 where Q is the ratio of the persistence of microbubbles of said chemical in an aqueous solution to the persistence of microbubbles of air in said solution, infusing free gas microbubbles of said chemical in said dispersion into an organism, and performing a human ultrasound scan on said organism. 15. A method of ultrasound imaging comprising the steps of: (1) providing a biocompatible ultrasound contrast agent comprising dodecafluoropentane to an organism; and (2) subjecting said organism to an ultrasound scan. 16. A method of ultrasound imaging comprising the steps of: (1) providing a biocompatible ultrasound contrast agent comprising dodecafluoropentane to a human; and (2) subjecting said human to an ultrasound scan. 17. A method of ultrasound imaging comprising the steps of: (1) providing a biocompatible ultrasound contrast agent comprising a member of the group consisting of hexafluoropropylene, octafluoropropane, octofluoro-2-butene, hexafluoro-2-butyne, hexafluorobuta-1,3-diene, octafluorocyclobutane and decafluorobutane to an animal; and (2) performing an ultrasound scan on said animal.