Reverse wound electrodes
An implantable lead includes an insulative sheath and a coil member; the coil member including a conductor wound from a proximal end of the coil member to a distal end and reverse wound back toward the proximal end to form an electrode on an outer diameter of the coil member adjacent and distal to the insulative sheath.
1. An implantable lead comprising:
an insulative sheath; and
a coil member extending through the insulative sheath and including first and second parallel conductors wound together to form interlaced coil windings;
wherein the first conductor winds from a proximal end of the coil member to a first distal end section of the coil member and reverse winds back toward the proximal end to form a first electrode, and
wherein the second conductor winds from the proximal end of the coil member to a second distal end section of the coil member and reverse winds back toward the proximal end to form a second electrode.
2. The implantable lead of claim 1 , wherein a length of each of the first and second electrodes is between approximately 2 mm and 3 cm.
3. The implantable lead of claim 1 , wherein a length of each of the first and second electrodes is between approximately 3 cm and 6 cm.
4. The implantable lead of claim 1 , wherein the insulative sheath includes an outer diameter and the first electrode forms a second outer diameter of the coil member, the second outer diameter being substantially equal to the outer diameter of the insulative sheath.
5. The implantable lead of claim 1 , further comprising
an inner tubing forming a lumen and extending within the coil member from the proximal end to the second distal end section; and
a fiber core extending within the lumen from the proximal end to the second distal end section where it is joined to an electrode tip.
6. The implantable lead of claim 1 , wherein the coil member further includes a third conductor in parallel with the first and second conductors and wound together with them to form interlaced coil windings; the third conductor winding from the proximal end of the coil member to a location between the first distal end section and the second distal end section and reverse winding back toward the proximal end to form a third electrode at a location intermediate the first and second electrodes.
7. The implantable lead of claim 6 , wherein the coil member further includes a fourth conductor in parallel with the first, second and third conductors and wound together with them to form interlaced coil windings; the fourth conductor winding from the proximal end of the coil conductor to a location between the first distal end section and the second distal end section and reverse winding back toward the proximal end to form a fourth electrode at a second location intermediate the first and second electrodes.
8. The implantable lead of claim 1 , further comprising an insulated cable conductor extending from the proximal end of the coil member.