A sleeve for a medical instrument, in particularly for accessing the human or animal body, for example, the eye, preferably as an infusion set for an ultrasound needle (1) for breaking up and removing tissue, comprising a body (2) with a connection region (3) and a probe region (4) enclosing the instrument or needle up to the free end (5) thereof at a small separation, such that in the region between the instrument or needle and the body (2), a fluid may be pumped, wherein the body (2) is preferably produced in one piece from rubber or soft plastic, characterised in that at least the probe region (4), is partly reinforced by coating and/or reaction and/or diffusion at least at the surface. A method for producing a corresponding sleeve is also disclosed.
