Claims for Patent: 7,842,283

Summary for Patent: 7,842,283

Title:	Generation of therapeutic microfoam
Abstract:	A method for producing a microfoam suitable for use in scleropathy of blood vessels comprises introducing a physiologically acceptable blood-dispersible gas into a container (1) holding an aqueous sclerosant liquid and releasing the mixture of blood-dispersible gas and sclerosant liquid, whereby upon release of the mixture the components of the mixture interact to form a microfoam.
Inventor(s):	Harman; Anthony David (Henley-on-Thames, GB), Harper; Paul (Buckinghamshire, GB), Pollock; Neil (Hertfordshire, GB), Sinclair; Gary Stewart (Suffolk, GB)
Assignee:	BTG International Limited (London, GB)
Application Number:	11/580,059
Patent Claims:	1. A device for producing a microfoam suitable for use in scleropathy of blood vessels, comprising: a housing in which is situated a pressurisable chamber containing a solution comprising at least one sclerosing agent in a physiologically acceptable solvent; a pathway with at least one outlet orifice by which the solution may pass from the pressurisable chamber to an exterior of the device through the at least one outlet orifice; and a mechanism by which the pathway from the pressurisable chamber to the exterior can be opened or closed such that, when the pressurisable chamber is pressurised and the pathway is open, fluid will be forced along the pathway and through the at least one outlet orifice; wherein the housing includes an inlet for the admission of a pressurised source of physiologically acceptable gas that is dispersible in blood, the physiologically acceptable gas being in contact with the solution upon activation of the mechanism to produce a gas-solution mixture, wherein the pathway to the exterior of the housing includes at least one foaming element, and wherein the physiologically acceptable gas that is dispersible in the blood is stored in a container provided with engaging means for engaging with the housing holding the solution comprising the at least one sclerosing agent and wherein the solution is stored in the presence of at least one inert gas. 2. The device as claimed in claim 1, wherein the at least one foaming element includes at least one passage having a cross sectional dimension of 0.1 .mu.m to 30 .mu.m, through which the gas-solution mixture is passed to reach the exterior of the device, the passing of the gas-solution mixture through the passage forms a microfoam ranging from 0.07 to 0.19 g/ml in density and having a half-life of at least 2 minutes. 3. The device as claimed in claim 1, wherein the pressurized source of physiologically acceptable gas is removed before the gas-solution mixture is released, having pressurised the gas-solution mixture to a pre-determined level before removal. 4. The device as claimed in claim 3, wherein the inlet for the admission of the physiologically acceptable gas includes the at least one outlet orifice for dispensing the gas-solution mixture. 5. The device as claimed in claim 1, wherein the engaging means includes an intermediate element. 6. The device as claimed in claim 5, wherein part of the intermediate element is removable before the gas-solution mixture is released, having pressurised the gas-solution mixture to a pre-determined level before removal. 7. The device as claimed in claim 5, wherein the intermediate element includes at least one foaming element to allow the components of the gas-solution mixture to interact to form the microfoam. 8. The device as claimed in claim 1, wherein the engaging means includes a connector, a first end of the connector being configured to engage with the housing and a second end of the connector being configured to engage with the container in which the pressurized source of physiologically acceptable gas is stored. 9. The device as claimed in claim 8, wherein the connector includes a substantially cylindrical element with open ends. 10. The device as claimed in claim 8, wherein the connector includes a cam track, whereby rotation of the containers relative to each other moves them together in a controlled fashion. 11. The device as claimed in claim 10, wherein the cam track is further provided with a release track for separating the containers again. 12. The device as claimed in claim 10, wherein at least one detent is provided in the cam track to gauge the progress of the introduction of the physiologically acceptable gas that is dispersible in the blood. 13. The device as claimed in claim 1, wherein a removable spacer is provided to prevent the container and the housing from being pushed together until required. 14. The device as claimed in claim 13, wherein the removable spacer takes the form of an annular collar positioned in between a connector in two parts. 15. The device as claimed in claim 8, wherein the connector includes an aerosol valve actuator mechanism, and wherein the container and the housing may be separated to leave the aerosol valve actuator mechanism attached to the housing. 16. A device for producing a microfoam suitable for use in scleropathy of blood vessels, comprising: a housing in which is situated a pressurisable chamber containing a solution comprising at least one sclerosing agent in a physiologically acceptable solvent; a pathway with at least one outlet orifice by which the solution may pass from the pressurisable chamber to an exterior of the device through the at least one outlet orifice; a mechanism by which the pathway from the pressurisable chamber to the exterior can be opened or closed such that, when the pressurisable chamber is pressurised and the pathway is open, fluid will be forced along the pathway and through the at least one outlet orifice; and a pressurised container containing a physiologically acceptable blood-dispersible gas; wherein the housing includes an inlet for the admission of the blood-dispersible gas, the gas being in contact with the solution upon activation of the mechanism to produce a gas-solution mixture and wherein the solution is stored in the presence of at least one inert gas. 17. The device as claimed in claim 16, wherein the pathway to the exterior of the housing includes at least one foaming element. 18. The device as claimed in claim 16, wherein the housing in which is situated the pressurisable chamber containing the solution of the sclerosing agent and the pressurized container containing the physiologically acceptable blood-dispersible gas are contained within a sealed package.