Self-expanding neurostimulation leads having broad multi-electrode arrays

Abstract

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.

What is claimed is: 
     
         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%.