Apparatus for delivering material into a patient includes a catheter (20) having a proximal end (22) and a distal end (24). Material, preferably of filamentary or thread form, is fed from a material supply (30) into a Y-fitting (60) having a main branch (66) and a side branch (72). The side branch (72) is connected to a source of driving fluid (42) able to feed drive fluid under pressure into the material carrier so as to pull material forwardly and out of the distal end (24) of the catheter (20). The assembly includes an inner cannula (50) within which material is passed from the material source (30). This increases the speed of delivery of material though the device (10) and reduces the amount of drive fluid which is required.
