A phantom for medical imaging instrumentation, the phantom including a first hydrogel matrix, said matrix containing additives for simulating the optical and acoustic properties of a living organ or tissue. In the phantom, the additives include Indian ink or haemoglobin, silica powder and titanium dioxide powder. The phantom may contain a tumor simulator in solid or liquid form. It may also comprise several hydrogel matrices, each matrix including additives in different concentrations depending on the organ or tissue simulated. A method of producing the phantom includes one or more freeze-thaw cycles for optimizing the characteristics of the phantom.
