A medical balloon for endoluminal location within a patient, comprises a first layer 34 formed of a polymeric material and a second layer 36 that overlies the first layer 34 and is formed of a polymeric material within which there are rounded or cuboidal particles or grains 38. The outer surface of the second layer may be smooth (fig 2) or have a roughened or textured surface 40. The particles may be echogenic and/or radiopaque. The particles may have a diameter between 2 to 20 micrometers and may be formed of glass, carbon, metal, a polymer, ceramic or tungsten. The medical balloon may be a balloon catheter. A method of making the balloon by heating and inflating raw tubing formed of a polymeric material with two layers wherein the first and second layers of the tubing are heated in a mould and the particles are embedded in the second layer.
