| 摘要 |
An endoprosthesis for implantation in vessels of the human or animal body is designed as a tubular framework of filaments which are arranged in a helical line configuration and which form two entwined groups which run in opposite senses of rotation and in each case consist of a plurality of mutually twisted filaments. Each filament has a composite material (2) with continuous reinforcement fibres (4) made of high-strength inorganic material, preferably carbon, glass or Kevlar, which are embedded in a support material (3) made of a high-strength thermoplastic, preferably polyetheretherketone (PEEK) or polyether sulphone (PS). The composite material (2) can be surrounded by a sleeve (5) which is preferably made of material corresponding to the support material (3), but which can contain admixtures, for example medicaments. In order to accommodate medicaments or other active substances, the sleeve (5) can be designed to be porous. An X-ray contrast medium may be admixed to the material of the sleeve or the support material. To produce the composite material (2), the reinforcement fibres (4) are covered with support material in powder form and are pulled through a heated die - pultruded. The sleeve (5) can then be applied to the composite material (2) in a similar manner. In order to generate a porous structure, a granular and soluble material such as salt can be admixed with the sleeve material and is then washed out. <IMAGE> |
