Guiding medical devices and associated methods of manufacturing
A catheter assembly includes an inner liner made of flexible material and an outer layer having a steering mechanism. A catheter assembly is provided that includes an inner liner made of flexible material, and an outer layer having a steering mechanism that includes at least one wire and a corresponding lumen for each of the at least one wire through which the respective wire may travel. The outer layer includes a braided wire assembly that includes at least two wires braided into a wire mesh, and further includes a see-through portion positioned proximate a pull wire extraction location to facilitate extraction.
1. A method of manufacturing a catheter, comprising:
providing a mandrel;
placing a lining material over the mandrel to form an inner liner;
placing a thermoplastic elastomer layer over the inner liner and adjacent the inner liner, at least along the mandrel at a location where one or more pull wires will be extracted;
providing at least one pull wire;
placing a flexible liner over each of the at least one pull wires to create at least one lumen;
placing a braided wire assembly over the inner liner, the thermoplastic elastomer layer, and the at least one lumen, the braided wire assembly including at least two wires braided into a wire mesh;
providing pull wire access areas in the braided wire assembly;
covering the braided wire assembly with one or more melt processing polymers having decreasing durometers from proximal to distal end of the mandrel;
covering a portion of the braided wire assembly proximate the location where the one or more pull wires will be extracted with a melt processing polymer that is substantially see-through;
applying sufficient heat to the one or more melt processing polymers and the see-through melt processing polymer to raise the temperature of the polymer above its melting point;
cooling the assembly; and
removing the mandrel, thereby forming a catheter.
2. The method of claim 1 , wherein the braided wire assembly is placed over the inner liner and the at least one lumen in a consistent braid pattern.
3. A method of manufacturing a catheter, comprising the steps of:
providing a mandrel;
placing a lining material over the mandrel to form an inner liner;
placing a thermoplastic elastomer layer over the inner liner and adjacent the inner liner;
providing at least one wire;
placing a flexible liner over each of the at least one wires to create at least one lumen;
placing a braided wire assembly over the inner liner, the thermoplastic elastomer layer, and the at least one lumen, the braided wire assembly including at least two wires braided into a wire mesh;
covering the braided wire assembly with one or more melt processing polymers having a durometer at the proximal end that differs from the durometer at the distal end of the mandrel;
applying sufficient heat to the melt processing polymers to raise the temperature of the polymer above their melting point;
cooling the assembly; and
removing the mandrel, thereby forming a catheter.
4. The method of claim 3 , wherein the durometer at the distal end is greater than the durometer at the proximal end.
5. The method of claim 3 , wherein the durometer at the distal end is less than the durometer at the proximal end.
6. The method of claim 3 further comprising the steps of:
covering a portion of the braided wire assembly proximate the location where the one or more pull wires will be extracted with a melt processing polymer that is substantially see-through;
applying sufficient heat to the one or more melt processing polymers and the see-through melt processing polymer to raise the temperature of the polymer above its melting point.
7. A method of manufacturing a catheter, comprising the steps of:
forming a tubular inner liner about a mandrel, the inner liner having a proximal end and a distal end, wherein the inner liner is polymeric;
placing a thermoplastic elastomer layer over the inner liner and adjacent the inner liner;
providing at least one pull wire;
forming a torque transfer layer over a portion of the liner and the thermoplastic elastomer layer, the torque transfer layer comprising a plurality of braided flat wires;
providing pull wire access areas in the torque transfer layer;
forming an outer sheath about the torque transfer layer, wherein the inner liner and the outer sheath define a catheter wall, and wherein the outer sheath comprises a melt-processing polymer;
covering a portion of the torque transfer layer proximate the location where the one or more pull wires will be extracted with a melt processing polymer that is substantially see-through;
applying sufficient heat to the melt processing polymer and the see-through melt processing polymer to raise the temperature of the polymer above its melting point
allowing the heated melt processing polymer and see-through melt processing polymer to cool until they each re-solidify; and
removing the mandrel.
8. The method of claim 7 , wherein forming the torque transfer layer comprises:
braiding the plurality of flat wires into a braided wire assembly at a braid density of between 10 PPI and 90 PPI.
9. The method of claim 7 , wherein the outer sheath comprises a plurality of segments having different hardness characteristics joined together via a reflow bonding process.