Generation of therapeutic microfoam

Abstract

Improved therapeutic sclerosing microfoams and methods and devices for making them are provided that have advantage in producing a consistent profile injectable foam with minimal input by the physician yet using high volume percentages of blood dispersible gases, thus avoiding use of potentially hazardous amounts of nitrogen.

1 - 81 . (canceled) 
     
     
         82 . A microfoam comprising a gas component and an aqueous sclerosant liquid wherein the microfoam is obtained by mixing the components by passing the gas component and the aqueous sclerosant liquid through at least one passage at least one time, wherein:
 the gas component comprises a physiologically acceptable blood dispersible gas comprising 10 to 100% vol/vol carbon dioxide or a mixture of 10 to 100% vol/vol carbon dioxide with the remaining gas oxygen,   and the aqueous sclerosant liquid comprises a sclerosing agent suitable for use in sclerotherapy of blood vessels,   and the at least one passage has a diameter ranging from about 5 μm to about 25 μm.   
     
     
         83 . The microfoam of  claim 82 , wherein the physiologically acceptable blood dispersible gas comprises 10 to 40% vol/vol carbon dioxide or a mixture of 10 to 40% carbon dioxide vol/vol and 60 to 90% vol/vol oxygen. 
     
     
         84 . The microfoam of  claim 82 , wherein the physiologically acceptable blood dispersible gas comprises 20 to 30% vol/vol carbon dioxide or a mixture of 20 to 30% carbon dioxide vol/vol and 70 to 80% vol/vol oxygen. 
     
     
         85 . The microfoam of  claim 82 , wherein the aqueous sclerosant liquid comprises 1% vol/vol polidocanol in an aqueous carrier. 
     
     
         86 . The microfoam of  claim 82 , wherein a density of the microfoam ranges from 0.07 g/ml to 0.19 g/ml. 
     
     
         87 . The microfoam of  claim 86 , wherein the density of the microfoam ranges from 0.11 g/ml to 0.14 g/ml. 
     
     
         88 . The microfoam of  claim 82 , wherein the microfoam has a half-life of at least 2 minutes. 
     
     
         89 . The microfoam of  claim 82 , wherein the aqueous sclerosant liquid is a solution of polidocanol in an aqueous carrier or sodium tetradecylsulfate (STS) in an aqueous carrier. 
     
     
         90 . The microfoam of  claim 89 , wherein the concentration of polidocanol ranges from 0.5 to 4% vol/vol in the liquid. 
     
     
         91 . A microfoam obtained by passing a gas component and a sclerosant liquid at least one time through at least one passage having a diameter ranging from about 5 μm to about 25 μm, comprising:
 the gas component comprising about 20 to about 99.99% vol/vol carbon dioxide or a mixture of about 20 to about 99.99% vol/vol carbon dioxide and about 0.01 to about 80% vol/vol oxygen; and 
 the sclerosant liquid comprising polidocanol or sodium tetradecylsulfate (STS). 
 
     
     
         92 . The microfoam of  claim 91 , wherein the sclerosant liquid comprises polidocanol in an aqueous carrier or sodium tetradecylsulfate (STS) in an aqueous carrier. 
     
     
         93 . The microfoam of  claim 92 , wherein the sclerosant liquid comprises about 1% vol/vol polidocanol. 
     
     
         94 . The microfoam of  claim 92 , wherein the sclerosant liquid comprises about 0.5 to about 4% vol/veal polidocanol. 
     
     
         95 . The microfoam of  claim 91 , wherein a density of the microfoam ranges from about 0.09 g/ml to about 0.16 g/ml. 
     
     
         96 . The microfoam of  claim 91 , wherein the microfoam has a half-life of at least 3 minutes. 
     
     
         97 . A device for producing a microfoam for use in sclerotherapy of blood vessels, comprising:
 a chamber fixedly coupled to a support, wherein the chamber has at least one outlet;   a pathway in fluid communication with the at least one outlet, wherein the pathway includes at least one passage having a diameter ranging from about 5 μm to about 25 μm that is moveably coupled to the support; and   a pressurization mechanism configured to apply a pressure to a fluid within the chamber to force the fluid through the pathway to form a microfoam.   
     
     
         98 . The device of  claim 97 , wherein the fluid comprises a physiologically acceptable blood dispersible gas comprising 10 to 100% vol/vol carbon dioxide or a mixture of 10 to 100% vol/vol carbon dioxide with the remaining gas oxygen. 
     
     
         99 . The device of  claim 97 , wherein the at least one passage includes at least one of a porous membrane, a mesh, a screen, and a sintered material. 
     
     
         100 . The device of  claim 97 , wherein the pathway comprises a plurality of passages arranged in parallel. 
     
     
         101 . The device of  claim 97 , further including a valve in communication with the at least one outlet and configured to direct the microfoam to a first outlet conduit and a second outlet conduit. 
     
     
         102 . A method for producing a microfoam suitable for use in sclerotherapy of blood vessels, comprising:
 passing a mixture of a blood dispersible gas and an aqueous sclerosant liquid through one or more passages having a diameter ranging from about 5 μm to about 25 μm,   wherein the blood dispersible gas comprises 10 to 100% vol/vol carbon dioxide or a mixture of 10 to 100% vol/vol carbon dioxide with the remaining gas oxygen.   
     
     
         103 . The method of  claim 102 , wherein the gas comprises at least about 90% vol/vol carbon dioxide. 
     
     
         104 . The method of  claim 103 , wherein the gas comprises at least about 99.99% vol/vol carbon dioxide. 
     
     
         105 . The method of  claim 104 . wherein the gas and liquid are passed through the at least one passage between 2 and 2,000 times. 
     
     
         106 . The method of  claim 105 , wherein the gas and liquid are passed through the at least one passage between 4 and 200 times. 
     
     
         107 . The method of  claim 102 , wherein the gas and liquid are passed through at least one of a porous membrane, a mesh, a screen, and a sintered material.