Abstract: A method of obtaining an image of a part of a patient, comprising: (a) providing microcapsules which have been formed by (i) providing a solution of a material in an aqueous solvent containing water and a liquid of greater volatility than water and (ii) spraying the said solution into a gas such that the aqueous solvent evaporates, thereby forming hollow microcapsules suitable for use as an echogenic contrast agent, (b) injecting the microcapsules into a patient, and (c) subjecting the patient to ultrasonic energy to obtain an image based on the ultrasound reflectivity transmissibility or resonance of the microcapsules, characterized in that at least 5 minutes elapse between steps (b) and (c). The patient can be exercised between administration and imaging without having to be reinjected.

Abstract: A method of generating an ultrasound image comprising the steps of (i) introducing into the location to be imaged an ultrasound contrast agent obtained by spraying a solution or suspension of a wall forming material into a heated gas to form hollow microcapsules, (ii) exposing the microcapsules to ultrasound energy at an insonation frequency of less than 3.5 MHz and (iii) creating an image based on the scattering of the ultrasound energy by the microcapsules.

Abstract: A method of generating an ultrasound image comprising the steps of (i) introducing into the location to be imaged an ultrasound contrast agent obtained by spraying a solution or suspension of a wall forming material into a heated gas to form hollow microcapsules, (ii) exposing the microcapsules to ultrasound energy of an intensity of at least 100 kPa and (iii) creating an image based on the scattering of the ultrasound energy by the microcapsules.