Implantable lead and surgical accessories

摘要

Leads for chronic implantation in the brain or other anatomical targets utilize tubular stylet means which are external to the lead. The lead comprises a distal electrode terminal, a proximal connector terminal, and a conductor cable having a reinforced distal portion and a stepped outside diameter providing a shoulder which cooperates with the distal end of the external stylet means. The substantial stiffness of the external stylet allows implantation of the lead without a brain-entering cannula. A tubular stylet spacer is employed to minimize lead dislodgement due to disassembly and removal of the lead introduction tools. Externalized stylet allows the conductor cable to have a small outside diameter and a desirably short length. A method of terminating conductors to electrodes using inserts is suitable for very fine wires and stranded conductors. A reinforced electrode terminal construction enables robust small-dimensioned terminal and high localization accuracy when introduced with external stylet means.

主权项

1. An implantable electrical lead having an elongated body having a proximal end and a distal end, said elongated body having a stepped outside diameter and a stepped body portion having a proximally facing shoulder formed by said stepped outside diameter, said lead comprising:
(A) an electrode terminal at said distal end of said lead, said electrode terminal comprising a body and at least one electrode embedded in said body; (B) a connector terminal at said proximal end of said lead, said connector terminal having a body and at least one contact embedded in said body; (C) a conductor cable between said electrode terminal and said connector terminal, said cable having an insulating jacket and at least one conductor encased in said jacket, said conductor electrically connecting said electrode to said contact; (D) a removable stylet assembly comprising a stylet and a stylet spacer, said stylet spacer occupying the radial space between said stylet and said lead, said stylet having a distal end, a proximal end, and a central lumen, said lumen accommodating said lead and said stylet spacer so that said stylet and said stylet spacer are external to said lead; whereby after said lead is implanted in an anatomical target, said stylet spacer can be removed while said distal end of said stylet is bearing on said shoulder to hold said lead from retracting, and wherein the removal of said stylet spacer clears the radial space between said lead and said stylet, whereby said stylet can be subsequently removed without causing traction on said lead.