SELF-EXPANDING NEUROSTIMULATION LEADS HAVING BROAD MULTI-ELECTRODE ARRAYS
Self-expanding lead including a lead body having a distal body end, a proximal body end, and a central axis extending therebetween. The lead body includes first and second outer arms and an inner arm disposed between the first and second outer arms. The first and second outer arms and the inner arm extend lengthwise between the proximal body end and the distal body end. The lead also includes an array of electrodes that are configured to apply a neurostimulation therapy within an epidural space of a patient. At least some of the electrodes are positioned along the first and second outer arms. Each of the first and second outer arms includes a resilient member that is biased to flex the corresponding first and second outer arms from a collapsed condition to an expanded condition in a lateral direction away from the inner arm.
The present application is a continuation of U.S. patent application Ser. No. 14/048,352, filed Oct. 8, 2013, which claims the benefit of U.S. Provisional Application No. 61/753,429, filed on Jan. 16, 2013, which is incorporated by reference in its entirety.
FIELD OF THE INVENTIONOne or more embodiments of the subject matter described herein generally relate to systems having leads for generating electric fields proximate to nerve tissue.
BACKGROUNDNeurostimulation systems (NS) include devices that generate electrical pulses and deliver the pulses to nerve tissue to treat a variety of disorders. Spinal cord stimulation (SCS) is a common type of neurostimulation. In SCS, electrical pulses are delivered to nerve tissue in the spine typically for the purpose of chronic pain control. While a precise understanding of the interaction between the applied electrical energy and the nerve tissue is not fully appreciated, it is known that application of an electric field to spinal nerve tissue can effectively mask or alleviate certain types of pain transmitted from regions of the body associated with the stimulated nerve tissue. SCS may have applications other than pain alleviation as well.
NS and SCS systems generally include a pulse generator and one or more leads electrically coupled to the pulse generator. A lead includes an elongated body of insulative material. A stimulating end portion of the lead includes multiple electrodes that are electrically coupled to the pulse generator through wire conductors. The stimulating end portion of a lead is implanted proximate to nerve tissue (e.g., within epidural space of a spinal cord) to deliver the electrical pulses. A trailing end portion of the lead body includes multiple terminal contacts, which are also electrically coupled to the wire conductors. The terminal contacts, in turn, are electrically coupled to the pulse generator. The terminal contacts receive electrical pulses from the pulse generator that are then delivered to the electrodes through the wire conductors to generate the electric fields. The pulse generator is typically implanted within the individual and may be programmed (and re-programmed) to provide the electrical pulses in accordance with a designated sequence.
Typically, one of two types of leads is used. The first type is a percutaneous lead, which has a rod-like shape and includes electrodes spaced apart from each other along a single axis. The second type of lead is a laminectomy or laminotomy lead (hereinafter referred to as a paddle lead). A paddle lead has an elongated planar body with a thin rectangular shape (i.e., paddle-like shape). Although the paddle lead may include only one row or column of electrodes, the paddle lead typically includes an array of electrodes that are spaced apart from each other along a substantially common plane. The number of electrodes may be, for example, two, four, eight, or sixteen.
A single paddle lead enables more coverage of the nerve tissue relative to a single percutaneous lead. However, due to their dimensions and physical characteristics, paddle leads require a surgical procedure (e.g. a partial laminectomy) to implant the lead. The paddle lead is typically positioned within the epidural space adjacent to the dura of the spinal cord. Conventional percutaneous leads are inserted into the body through a narrow introducer. Compared to paddle leads, the percutaneous leads have dimensions that may enable an easier insertion into the spinal cord and/or may cause less trauma to the insertion site of the spinal cord.
Therefore, a need remains for implantable leads that may be inserted into the spinal cord with a simpler insertion procedure than conventional paddle leads and also have electrode coverage of the nerve tissue that is broader than conventional percutaneous leads.
BRIEF SUMMARYIn accordance with an embodiment, a self-expanding lead is provided that includes a lead body having a distal body end, a proximal body end, and a central axis extending therebetween. The lead body includes first and second outer arms and an inner arm disposed between the first and second outer arms. The first and second outer arms and the inner arm extend lengthwise between the proximal body end and the distal body end. The lead also includes an array of electrodes that are configured to apply a neurostimulation therapy within an epidural space of a patient. At least some of the electrodes are positioned along the first and second outer arms. Each of the first and second outer arms includes a resilient member that is biased to flex the respective outer arm from a collapsed condition to an expanded condition in a direction that is away from the inner arm. The resilient member permits the respective outer arm to flex toward the inner arm from the expanded condition to the collapsed condition when a force is applied.
In accordance with another embodiment, a self-expanding lead is provided that includes first and second outer arms extending between respective proximal and distal arm ends. Each of the first and second outer arms includes electrodes that are positioned along a length of the respective outer arm. The lead also includes an inner arm that is disposed between the first and second outer arms. The inner arm extends between a respective base end and a respective distal arm end. The proximal ends of the inner arm and the first and second outer arms are coupled to each other proximate to a proximal body end of the self-expanding lead. The lead also includes a multi-electrode array having the electrodes of the first and second arms. The multi-electrode array is configured to apply a neurostimulation therapy within an epidural space of a patient. Each of the first and second outer arms includes a resilient member that is biased to flex the respective outer arm from a collapsed condition to an expanded condition in a direction that is away from the inner arm. The resilient member permits the respective outer arm to flex toward the inner arm from the expanded condition to the collapsed condition when a force is applied.
While multiple embodiments are described, still other embodiments of the described subject matter will become apparent to those skilled in the art from the following detailed description and drawings, which show and describe illustrative embodiments of disclosed inventive subject matter. As will be realized, the inventive subject matter is capable of modifications in various aspects, all without departing from the spirit and scope of the described subject matter. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
Embodiments described herein include self-expanding leads that are capable of flexing into an operative shape or configuration as the self-expanding lead is inserted into the epidural space. For example, the self-expanding lead may include one or more resilient members that are biased to expand the self-expanding lead when the self-expanding lead is permitted to expand (e.g., when a force is removed). The self-expanding lead may include a plurality of arms, at least one of which may be capable of flexing into an expanded condition. The individual arms may reduce the amount of pressure along the spinal nerves within the epidural space relative to conventional paddle leads.
The individual arms of the lead may include one or more electrodes. Collectively, the electrodes of the individual arms may form a multi-electrode array (e.g., two-dimensional array) that provides electrode coverage comparable to conventional paddle leads. For instance, the multi-electrode array may be configured to have a coverage similar to Penta™ paddle leads distributed by St. Jude. In addition to the broad electrode coverage, the expandable/collapsible lead may enable delivery of the lead through introducers that are typically used for inserting percutaneous leads. As such, incisions for inserting the lead into the patient may be smaller than those used for inserting paddle leads, which may reduce recovery and clinical cost.
The controller 151 may be programmable controller that controls the various modes of stimulation therapy for the NS device 150. The controller 151 may include a microprocessor, or equivalent control circuitry, designed specifically for controlling delivery of stimulation therapy and may further include RAM or ROM memory, logic and timing circuitry, state machine circuitry, and I/O circuitry. The microcontroller 151 may have the ability to process or monitor input signals (data) as controlled by a program code stored in memory. The details of the design and operation of the microcontroller 151 are not critical to the present invention. Rather, any suitable microcontroller 151 may be used.
The NS device 150 may comprise a separate or an attached extension component 170. If the extension component 170 is a separate component, the extension component 170 may connect with the “header” portion of the NS device 150 as is known in the art. If the extension component 170 is integrated with the NS device 150, internal electrical connections may be made through respective conductive components. Within the NS device 150, electrical pulses are generated by the pulse generating circuit module 152 and are provided to the switching circuit module 157. The switching circuit module 157 connects to outputs of the NS device 150. Electrical connectors (e.g., “Bal-Seal” connectors) within a connector portion 171 of the extension component 170 or within the header portion may be employed to conduct the electrical pulses. Terminal contacts (not shown) of one or more neurostimulator leads 110 are inserted within the connector portion 171 or within the header for electrical connection with respective connectors. Thereby, the pulses originating from NS device 150 are provided to the neurostimulator lead 110. The pulses are then conducted through wire conductors of the lead 110 and applied to tissue of an individual via electrodes 111. In the illustrated embodiment, the neurostimulator lead is a lead configured for insertion after a laminectomy or a laminotomy. The neurostimulator lead 110 is hereinafter referred to as a “self-expanding lead.”
For implementation of the components within NS device 150, a processor and associated charge control circuitry for an implantable pulse generator is described in U.S. Patent Application Publication No. 2006/0259098, entitled “SYSTEMS AND METHODS FOR USE IN PULSE GENERATION,” which is incorporated herein by reference in its entirety. Circuitry for recharging a rechargeable battery of an implantable pulse generator using inductive coupling and external charging circuits are described in U.S. Pat. No. 7,212,110, entitled “IMPLANTABLE DEVICE AND SYSTEM FOR WIRELESS COMMUNICATION,” which is incorporated herein by reference in its entirety. One or more NS devices and one or more paddle leads that may be used with embodiments described herein are described in U.S. Patent Application Publication No. US 2013/0006341 in its entirety.
An example and discussion of “constant current” pulse generating circuitry is provided in U.S. Patent Application Publication No. 2006/0170486 entitled “PULSE GENERATOR HAVING AN EFFICIENT FRACTIONAL VOLTAGE CONVERTER AND METHOD OF USE,” which is incorporated herein by reference in its entirety. One or multiple sets of such circuitry may be provided within the NS device 150. Different pulses on different electrodes may be generated using a single set of pulse generating circuitry using consecutively generated pulses according to a “multi-stimset program.” Complex pulse parameters may be employed such as those described in U.S. Pat. No. 7,228,179, entitled “METHOD AND APPARATUS FOR PROVIDING COMPLEX TISSUE STIMULATION PATTERNS,” and International Patent Publication No. WO 2001/093953A1, entitled “NEUROMODULATION THERAPY SYSTEM,” each of which is incorporated herein by reference in its entirety. Alternatively, multiple sets of such circuitry may be employed to provide pulse patterns that include simultaneously generated and delivered stimulation pulses through various electrodes of one or more stimulation leads as is also known in the art. Various sets of parameters may define the pulse characteristics and pulse timing for the pulses applied to various electrodes as is known in the art. Although constant current pulse generating circuitry is contemplated for some embodiments, any other suitable type of pulse generating circuitry may be employed such as constant voltage pulse generating circuitry.
In some embodiments, a controller device 160 may be implemented to recharge battery 154 of the NS device 150. For example, a wand 165 may be electrically connected to the controller device 160 through suitable electrical connectors (not shown). The electrical connectors may be electrically connected to a primary coil 166 at the distal end of wand 165 through respective wires (not shown). The primary coil 166 may be placed against the patient's body immediately above the charging coil (or secondary coil) 153 of the NS device 150. The controller device 160 may generate an AC-signal to drive current through the primary coil 166. Current may be induced in the secondary coil 153 to recharge the battery 154.
In some embodiments, the controller device 160 preferably provides one or more user interfaces to allow the user to the NS device 150 according to one or more stimulation programs to treat the patient's disorder(s). Each stimulation program may include one or more sets of stimulation parameters including pulse amplitude, pulse width, pulse frequency or inter-pulse period, pulse repetition parameter (e.g., number of times for a given pulse to be repeated for respective stimset during execution of program), etc. The NS device 150 modifies its internal parameters in response to the control signals from controller device 160 to vary the stimulation characteristics of stimulation pulses transmitted through stimulation lead 110 to the tissue of the patient. Neurostimulation systems, stimsets, and multi-stimset programs are discussed in PCT Publication No. WO 01/93953, entitled “NEUROMODULATION THERAPY SYSTEM,” and U.S. Pat. No. 7,228,179, entitled “METHOD AND APPARATUS FOR PROVIDING COMPLEX TISSUE STIMULATION PATTERNS,” which are incorporated herein by reference.
In the illustrated embodiment, the arms 211-215 include first and second outer arms 211, 214, first and second inner arms 212, 213, and a center inner arm 215. The inner arms 212, 213, 215 are disposed between the outer arms 211, 214, and the center inner arm 215 is disposed between the first and second inner arms 212, 213. In some embodiments, the inner arms 212, 213 may be described or characterized intermediate arms 212, 213. Each of the arms 211-215 extends lengthwise between a respective distal arm end 218 (shown in
In the illustrated embodiment, the lead body 202 has a lead profile or footprint 225 that constitutes a spatial volume defined by exterior surfaces of the lead body 202 when the leady body 202 is in a relaxed state. In
As shown, the lead profile 225 may include elongated windows or openings 241-244 that are defined between adjacent arms. More specifically, with respect to the illustrated embodiment, the lead body 202 defines the elongated window 241 between the outer arm 211 and the inner arm 212, the elongated window 242 between the inner arm 212 and the inner arm 215, the elongated window 243 between the inner arm 215 and the inner arm 213, and the elongated window 244 between the inner arm 213 and the outer arm 214. The elongated windows 241 extend lengthwise along the central axis 208 and widthwise between the adjacent arms. The elongated windows 241-244 reduce or shrink when the lead 200 is in a collapsed state.
When the lead 200 is in a relaxed state prior to insertion as shown in
During an implantation procedure, the distal body end 204 is typically the first end that is inserted through an incision and into the spinal column. As shown, the lead cable 210 extends away from the lead body 202 from the proximal body end 206. The lead cable 210 may include conductive pathways 286 (shown in
As shown in
When the lead 200 is disposed in the epidural space, one of the paddle sides may interface with nerve tissue and the other paddle side may interface with an anatomical structure (e.g., bone, ligament, or other portions of the spine). In some embodiments, the electrodes 250 may be exposed along each of the paddle sides 222, 224. In other embodiments, the electrodes 250 may be exposed only along one of the paddle sides, such as the paddle side 222 shown in
In the illustrated embodiment, each of the outer arms 211, 214 and each of the inner arms 212, 213 include a series or column of electrodes 250 that are spaced apart from each other along a length of the respective arm. When in an operative state (e.g., an expanded state), the arms are spaced apart from each other thereby laterally separating the electrodes 250 of adjacent arms. To form the multi-electrode array 252 with a predetermined configuration, the electrodes 250 may be disposed along the lengths of the respective arms at designated locations and the arms 211-215 may be configured to have a designated separation when in the expanded state so that the electrodes 250 form the multi-electrode array 252.
In the illustrated embodiment, multi-electrode array 252 includes a 4×5 grid of electrodes 250 in which the electrodes 250 are substantially evenly distributed along (e.g. parallel to) the central axis 208. In alternative embodiments, the electrodes 250 may form a single row or column that extends along the central axis 208 and are spaced apart from each other. In other embodiments, the multi-electrode array 252 may have a 4×4 grid of electrodes 250 or a 4×8 grid of electrodes 250. In particular embodiments, the multi-electrode array 252 may be configured to have a coverage similar to Penta™ paddle leads distributed by St. Jude.
To this end, the lead body 202 may include a plurality of resilient members 261-264 (shown in
In the illustrated embodiment, the cross-section of the arms 211-215 have a substantially circular shape or substantially square shape such that the arm width 281 and the arm height 283 are substantially equal In other embodiments, the arms 211-215 may have a substantially rectangular shape. For example, the arm width 281 may be about 2.25 mm and the arm height 283 may be about 1.0 mm.
As shown, the arms 211-215 comprise an insulative material 284 that may include the exterior surfaces of the arms 211-215. In
The inner arm 215 includes a steering lumen 288. The steering lumen 288 may be defined by an interior surface of the insulative material 284. The steering lumen 288 may extend lengthwise through the inner arm 215 from the proximal body end 206 (
The insulative material 284 may include one or more biocompatible materials. Non-limiting examples of such materials include polyimide, polyetheretherketone (PEEK), polyethylene terephthalate (PET) film (also known as polyester or Mylar), polytetrafluoroethylene (PTFE) (e.g., Teflon), or parylene coating, polyether bloc amides, polyurethane. In some embodiments, the material of the lead body 202 that surrounds the metal components (e.g., electrodes 250 and the conductive pathways 286 that couple to the electrodes 250) includes at least one of polyimide, polyetheretherketone (PEEK), polyethylene terephthalate (PET) film, polytetrafluoroethylene (PTFE), parylene, polyether bloc amides, or polyurethane.
In the illustrated embodiment, when the lead body 202 is in an expanded state, each of the arms 211-214 coincides with a body plane 298 prior to the arms 211-214 collapsing. As the arms 211-214 collapse, the arms 211-214 move along the body plane 298 in an inward direction toward the inner arm 215 and/or toward the central axis 208. When the arms 211-214 are in the collapsed conditions as shown in
At stage 401, the lead 410 is disposed within a cavity, such as the cavity 397 (
Before or after the lead 410 has been disposed within the insertion tool 414, the insertion tool 414 may be advanced into a patient (not shown) through one or more incisions. For example, the insertion tool 414 may be advanced through one or more incisions that provide access to the spinal cord (not shown). In some embodiments, the insertion tool 414 may be identical to the introducers that are used to insert percutaneous leads into the spinal cord. In other embodiments, the insertion tool 414 may not be identical, but may have dimensions that are approximate to or similar to the dimensions of conventional percutaneous introducers.
At stage 402, the distal body end 416 clears the end opening 412 of the insertion tool 414. As the lead 410 transitions to stage 403, the distal body end 416 may expand to have a larger lead profile. At this time, the distal body end 416 may engage tissue within the anatomical space (not shown). Geometries of the anatomical space, including the epidural space, vary from patient to patient. In some cases, it may be desirable for the lead 410 to be capable of moving around obstructions, such as bone or tissue, and/or to be capable for moving tissue without causing significant trauma to the patient. In accordance with some embodiments, the resiliency of the arms 421-424 at the distal body end 416 may be configured such that the distal body end 416 is capable of engaging and flexing to slide around tissue and/or is capable of engaging and moving tissue within the anatomical space.
At stage 404, the distal body end 416 has cleared the end opening 412 of the insertion tool 414 and a majority of a length of the lead 410 has advanced into the anatomical space. At stages 405 and 406, the proximal body end 418 has expanded such that the arms 421-424 are fully expanded and the lead 410 has a maximum lead profile. Before or after the lead 410 is properly position within the epidural space, the tool 414 may be withdrawn through the one or more incision cites.
The insertion process with respect to the lead 200 may be similar to the insertion process described with respect to
In the embodiment of
Accordingly, embodiments described herein may have a flexible membrane along one or both paddle sides. The flexible membrane may limit adhesion of the self-expanding lead to the patient by limiting growth of tissue or other material within the epidural space around the arms of the lead. In such embodiments that utilize a flexible membrane, the flexible membrane may be capable of folding over within the cavity of the insertion tool, such as the insertion tool 414, thereby permitting the expanding/collapsing abilities of the leads described herein.
The lead cable 860 may include conductive pathways (not shown), such as wire conductors, which extend from the lead body 852 to an NS device or pulse generator (not shown), such as the NS device 150 (
Although not shown, the lead body 852 may include a plurality of resilient members proximate to the distal body end 854 and a plurality of resilient members proximate to the proximal body end 856. The resilient members may be similar to the resilient members 261-264 and 271-274 (
In the illustrated embodiment, the inner arm 865 includes a steering lumen 888. The steering lumen 888 extends through the lead cable 860 into the inner arm 865. The steering lumen 888 may be defined by an interior surface of an insulative material of the lead cable 860 and the inner arm 865. As shown, the steering lumen 888 extends lengthwise through the inner arm 865 from the proximal body end 856 and through the distal body end 854. The steering lumen 888 is sized and shaped to receive an elongated tool, which is illustrated as a guide wire 892 in
In some embodiments, the center inner arm 865 may not include resilient material for flexing between different positions. For example, in particular embodiments, the center inner arm 865 may not include such resilient material and, instead, may include a more rigid material. The rigid material may be more suitable for receiving a tool, such as the guide wire 892.
However, the lead body 902 may have a steering lumen 904 that extends to and ends at a cable end 906 of a lead cable 908. As shown, a guide wire 910 may be inserted into the steering lumen 904 until a wire end 912 of the guide wire 910 engages the cable end 906 of the lead body 902. The guide wire 910 may be operated to move the lead body 902 into a designated orientation. For example, when the lead body 902 is inserted into the epidural space (not shown), the lead body 902 may be moved to into a designated orientation by the guide wire 910. More specifically, the lead body 902 may pivot (as indicated by the arrows) about a point 930 located within the cable end 906.
The method 800 also includes assembling (at 804) wire conductors and electrodes of the lead. The assembling (at 804) may include positioning the resilient members relative to the wire conductors and the electrodes. At 806, an insulative material may be applied (e.g., molded) to the assembly of wire conductors, electrodes, and resilient members. The insulative material may be a biocompatible material, such as the materials described herein. The insulative material may completely cover or insulate the wire conductors and at least partially cover the electrodes. The resilient members may be at least partially covered by the insulative material.
A lead body may be formed upon applying the insulative material at 806. The lead body may be similar to other leads or lead bodies described herein, such as the lead body 200. In particular, the lead body may include a plurality of arms that extend between a distal body end and a proximal body end of the lead body. For example, the arms may include first and second outer arms and an inner arm generally disposed between the first and second outer arms. The first and second outer arms and the inner arm may extend lengthwise between the proximal body end and the distal body end.
The electrodes may form a multi-electrode array that is configured to apply a neurostimulation therapy. Some or all of the electrodes may be positioned along the first and second outer arms. Each of the first and second outer arms may include at least one of the resilient members. The resilient members may bias the respective outer arm to flex from a collapsed condition to an expanded condition in a laterally-outward direction. The resilient members may also permit the respective outer arm to flex laterally-inward from the expanded condition to the collapsed condition when a force is applied.
Optionally, at 808, a flexible membrane may be applied to a paddle side of the lead body. The flexible membrane may be similar to the flexible membranes 602 or 702 (
It is to be understood that the subject matter described herein is not limited in its application to the details of construction and the arrangement of components set forth in the description herein or Illustrated in the drawings hereof. The subject matter described herein is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. Also, it is to be understood that phraseology and terminology used herein with reference to device or element orientation (such as, for example, terms like “central,” “upper,” “lower,” “front,” “rear,” “distal,” “proximal,” and the like) are only used to simplify description of one or more embodiments described herein, and do not alone indicate or imply that the device or element referred to must have a particular orientation. In addition, terms such as “outer” and “inner” are used herein for purposes of description and are not intended to indicate or imply relative importance or significance.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the presently described subject matter without departing from its scope. While the dimensions, types of materials and coatings described herein are intended to define the parameters of the disclosed subject matter, they are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the inventive subject matter should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
The following claims recite aspects of certain embodiments of the inventive subject matter and are considered to be part of the above disclosure.
Claims
1. A self-expanding lead comprising:
- a lead body having a distal body end, a proximal body end, and a central axis extending therebetween, the lead body comprising first and second outer arms and first and second inner arms, with first and second inner arms being disposed generally between the first and second outer arms, the first and second outer arms and first and second inner arms extending lengthwise between the proximal body end and the distal body end;
- a first arcuate joint connecting the distal ends of the first and second outer arms and a second arcuate joint connecting the distal ends of the first and second inner arms;
- an array of electrodes configured to apply a neurostimulation therapy within an epidural space of a patient, at least some of the electrodes being positioned along the first and second outer arms and the first and second inner arms;
- a resilient member disposed within each of the first arcuate joint and second arcuate joint, the resilient members being biased to flex the corresponding first and second outer arms and first and second inner arms from a collapsed condition to an expanded condition in a lateral direction away from the central axis, the resilient members permitting the corresponding first and second outer arms and the corresponding first and second inner arms to flex toward the central axis from the expanded condition to the collapsed condition when a force is applied;
- wherein the first and second outer arms and the first and second inner arms are all substantially coplanar when in the expanded condition.
2. The self-expanding lead of claim 1, and further including a center arm along the central axis, the center includes a steering lumen at the distal body end, the steering lumen sized and shaped to receive an elongated tool for directing the lead body during an insertion process.
3. The self-expanding lead of claim 2, wherein the steering lumen extends through the proximal body end to the distal body end.
4. The self-expanding lead of claim 1, wherein the first and second outer arms partially define first and second elongated windows, respectively, the first and second elongated windows extending between the proximal body end and distal body end and between the respective outer arm and the inner arm.
5. The self-expanding lead of claim 6, further comprising a flexible membrane that is coupled to the lead body and covers at least one of the first and second elongated windows.
6. The self-expanding lead of claim 4, wherein the lead body has opposite paddle sides when the first and second arms are in the expanded conditions, the self-expanding lead further comprising a flexible membrane that is coupled to the lead body and covers at least one of the paddle sides.
7. The self-expanding lead of claim 1, wherein each of the first and second arms has an arm cross-section that includes first and second dimensions, the first and second dimensions being perpendicular with respect to each other and differing by at most 50%.
8. A self-expanding lead comprising:
- first and second outer arms and first and second inner arms, extending between respective base and distal arm ends;
- a center arm disposed generally between the first and second inner arms, the center arm extending between a respective base end and a respective distal arm end, the base ends of the first and second inner arms and the center arm and second outer arms being coupled to each other proximate to a proximal body end of the self-expanding lead; and
- a multi-electrode array including a plurality of electrodes, the first and second arms including at least one electrode of the multi-electrode array and the first and second inner arms including at least one electrode;
- a first arcuate joint connecting the distal ends of the first and second outer arms;
- a second arcuate joint connecting the distal ends of the first and second inner arms;
- a first resilient member disposed within the first arcuate joint and a second resilient member being disposed in the second arcuate joint, the resilient members being biased to flex the corresponding first and second outer arms and first and second inner arms from a collapsed condition to an expanded condition in a lateral direction away from the central axis, the resilient members permitting the corresponding first and second outer arms and the corresponding first and second inner arms to flex toward the central axis from the expanded condition to the collapsed condition when a force is applied; and
- the center arm being connected to each of the first arcuate joint and the second arcuate joint;
- wherein the first and second outer arms and the first and second inner arms are all substantially coplanar when in the expanded condition.
9. The self-expanding lead of claim 8, wherein the center arm includes a steering lumen, the steering lumen sized and shaped to receive an elongated tool for directing the lead body during an insertion process.
10. The self-expanding lead of claim 9, wherein the first outer arm and the first inner arm are adjacent to each other and the second outer arm and the second inner arm are adjacent to each other, the first outer arm and first inner arm moving in a common direction toward the second outer arm and the second inner arm when the lead is collapsed.
11. The self-expanding lead of claim 8, wherein the self-expandable lead has opposite paddle sides when the first and second arms are in the expanded conditions, the self-expandable lead further comprising a flexible membrane that is coupled to the lead body and covers at least one of the paddle sides.
12. The self-expandable lead of claim 11, wherein the flexible membrane extends along only one of the paddle sides.
13. The self-expanding lead of claim 11, wherein the flexible membrane has electrode openings that expose portions of the electrodes along the at least one paddle side.
14. The self-expanding lead of claim 8, wherein each of the first and second arms has an arm cross-section that includes first and second dimensions, the first and second dimensions being perpendicular with respect to each other and differing by at most 50%.
Type: Application
Filed: Apr 6, 2016
Publication Date: Jul 28, 2016
Inventor: Alan De La Rama (Cerritos, CA)
Application Number: 15/092,454