Abstract: Lead fixation devices for mounting at a cranial burr hole and securing a medical lead implanted into a brain through the burr hole. One embodiment comprises a clamp having centrally disposed clamping walls activated by a plunger having actuating tabs. The clamping walls may be an integral part of a device base, or a separate part seated in a central opening of the base. The clamp is activated by pressing the actuating tabs of the plunger into apertures adjoining the clamping walls, which displaces the clamping walls to clamp the lead. Another embodiment comprises a base having a plurality of radial and peripheral lead retention grooves configured to securely retain a substantial segment of the lead at the exit from the burr hole. Still another embodiment comprises both a clamp and peripheral retention grooves to provide a dual fixation and strain relief of the lead within the lead fixation device.

Abstract: 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.

Abstract: A contact probe comprises conductively coupled plungers and a coil spring. The plungers have coupling means which enable them to be slidably and non-rotatably engaged. The spring is attached to the plungers in a manner that prevents rotation of the spring's ends. A desired magnitude of torsional bias is generated by twisting the spring a predetermined angle prior to attachment of the spring to the plungers. An additional torsional bias is generated by the tendency of the spring to twist when the spring is axially displaced. The resultant torsional bias rotatably biases the coupling means of the plungers against each other, generating contact forces for a direct conductive coupling between the plungers. The plungers are self-latching or are retentively attached to the spring using the torsional bias of the spring. Plungers with hermaphroditic coupling means can be fabricated from a sheet metal or a profiled stock by stamping or machining.

Abstract: An implantable stimulation lead for introduction into the brain or other anatomical target in a human body comprises a distal electrode terminal, a proximal connector terminal, and a connecting conductor cable. The led construction enables stylet means to bypass the cable and the connector terminal. A slotted cannula allows the cable and the connector terminal to be decoupled from the lead introduction tools. This enables a substantial stylet means and allows the cable and the connector terminal to be optimized without constraints of the lead introduction tools. The overall length of the lead is minimized and the conductor cable and the connector can be non-iso-diametric. A method of terminating conductors to electrodes using inserts is suitable for very fine wires and stranded conductors. The disclosed leads and accessories are applicable to stimulation leads, sensing leads, or any other lead that may be implanted with or without a stereotactic localization system.

Abstract: A low inductance contact comprises a coil spring and a conductively coupled pin. The pin has coupling surfaces which enable the coil spring to be attached to the pin in a manner that prevents rotation of the spring's ends. The spring provides an axial pin bias to contact tips, and a torsional bias for conductive coupling between the spring and the pin. The torsional bias is generated by an axial displacement of the spring and by twisting the spring a predetermined angle prior to attachment to the pin. A torsion-induced contact between the pin and the spring enables a conductive path through the pin, while bypassing the coils of the spring. The torsional bias further enables a positive attachment of the spring to the pin. Pins can be fabricated from a drawn profiled stock by stamping or machining. Essential pin coupling features can be prefabricated in a drawn profiled stock.

Abstract: A low inductance contact probe comprises conductively coupled plungers. The plungers have coupling means which enable them to be slidably and non-rotatably engaged. A coil spring is attached to the plungers in a manner that prevents rotation of the spring's ends. The spring provides an axial plunger bias, and a torsional bias for conductive coupling between the plungers. The torsional bias is generated by an axial displacement of the spring and by twisting the spring a predetermined angle prior to attachment to the plungers. Torsion-induced contact forces between the plungers assure a direct conductive path through the plungers. The torsional bias further enables a positive attachment of the spring to the plungers. Plungers with hermaphroditic coupling means can be fabricated from a drawn profiled stock by stamping or machining. Essential plunger coupling features can be prefabricated in a drawn profiled stock with a high degree of dimensional accuracy and reproducibility.

Abstract: An implantable connector electrically connects multi-conductor leads to an implantable medical device such as a neurostimulator. The connector is applicable to a variety of lead contact terminals, including iso-diametric terminals with ring contacts, paddle-shaped terminals with flat pad contacts, and orthogonal lead contact terminals. The connector is assembled directly into a hermetic feedthrough of the device and utilizes the feedthrough housing as a sustaining structure for connector pressurization. The feedthrough pins are integrated with compressible contacts in a manner that confines, protects, and precisely positions the compressible contacts. The compressible contacts can be coil springs, metal-particle-filled elastomer buttons, and fuzz buttons, and can be used with rigid tips where a contact preload and/or an enhanced contact tip robustness is desired.

Abstract: An implantable connector electrically connects multi-conductor leads to an implantable medical device such as a neurostimulator. The connector is assembled directly into a hermetic feedthrough of the device and utilizes the feedthrough housing as a sustaining structure for connector pressurization. The feedthrough pins are adapted to directly connect, confine, protect, and precisely position respective resilient compressible contacts. The compressible contacts can be coil springs, metal-particle-filled elastomer buttons, and fuzz buttons, and can be used with rigid tips where a contact preload and/or an enhanced contact tip robustness is desired. In one method of connector assembly an iso-diametric lead proximal terminal is first inserted into a seal without significant interference, and the resulting lead-seal assembly is subsequently installed in a clamping cover.

Abstract: An implantable connector electrically connects multi-conductor leads to an implantable medical device such as a neurostimulator. The connector is assembled directly into a hermetic feedthrough of the device and utilizes the feedthrough housing as a sustaining structure for connector pressurization. The feedthrough pins are adapted to directly connect, confine, protect, and precisely position respective resilient compressible contacts. The compressible contacts can be coil springs, metal-particle-filled elastomer buttons, and fuzz buttons, and can be used with rigid tips where a contact preload and/or an enhanced contact tip robustness is desired. In one method of connector assembly an iso-diametric lead proximal terminal is first inserted into a seal without significant interference, and the resulting lead-seal assembly is subsequently installed in a clamping cover.

Abstract: An implantable connector electrically connects multi-conductor leads to an implantable medical device such as a neurostimulator. The connector is assembled directly into a hermetic feedthrough of the implantable device and utilizes the feedthrough housing as a sustaining structure for connector clamping. The receptacle contacts detachably connect proximal lead contacts to corresponding feedthrough pins, which provide pass-through connections to electronic circuitry contained in a hermetically sealed case. The receptacle contact has resilient contact tines designed to engage a corresponding lead contact in a sliding manner. The receptacle contact is integrated with a contact guard which protects the receptacle contact from inadvertent handling damage. The contact guard is substantially more rigid than the resilient contact to resist deformation. The contact guard protectively shields the receptacle contact tines and prevents unintended contact tine excursion.