A device for generating microbubbles in a gas and liquid mixture and injection device, the device comprising: a housing defining a mixing chamber means for mixing solution contained in the mixing chamber to generate microbubbles in the solution a needle array removably attached to the housing and in fluid connection with the mixing chamber, the needle array including at least one needle and at least one pressure sensor for measuring tissue apposition pressure, the pressure sensor being mounted on one of the housing and the needle array.
