DORSAL ROOT GANGLIA SURGICAL LEADS
Implementations described and claimed herein provide paddle leads for dorsal root ganglia (DRG) stimulation and methods of implanting the same. In one implementation, the paddle lead has a small profile facilitating deployment into a target space in the neuroforamen dorsal to the DRG and below the vertebral lamina. A paddle body of the paddle lead may include a living hinge and/or a contoured profile to further facilitate implantation in the target space. For suture assisted deployment as well as to resist migration of the paddle lead once deployed, the paddle lead may include a suture loop configuration. The paddle lead further includes an electrode array having electrode contacts arranged in a two dimensional configuration pattern to create an electrical field optimized for stimulation of the DRG.
Aspects of the present disclosure relate to leads surgically implantable in a patient for electrical stimulation of nerve or tissue and more particularly to leads providing controlled stimulation of a spinal and/or paraspinal nerve root ganglion, such as a dorsal root ganglion.
BACKGROUNDMedical conditions may be treated through the application of electrical stimulation. For example, Spinal Cord Stimulation (SCS) involves driving an electrical current into particular regions of the spinal cord to induce paresthesia, which is a subjective sensation of numbness or tingling in a region of the body associated with the stimulated spinal cord region. Paresthesia masks the transmission of chronic pain sensations from the afflicted regions of the body to the brain, thereby providing pain relief to the patient. Typically, an SCS system delivers electrical current through electrodes implanted along the dura layer surrounding the spinal cord. The electrodes may be carried, for example, by a paddle lead, which has a paddle-like configuration with the electrodes arranged in one or more independent columns on a relatively large surface area, or a percutaneous lead, which includes the electrodes arranged around a tube. Paddle leads are generally delivered into the affected spinal tissue through a laminectomy, involving the removal of laminar vertebral tissue to allow access to the dura layer and positioning of the paddle lead. Conventional delivery of paddle leads thus generally requires large incisions and substantial removal of lamina, resulting in trauma to the patient and longer procedure time. On the other hand, however, paddle leads may resist migration once implanted, provide enhanced stimulation, and utilize less energy, among other advantages. Further, paddle leads may be advantageous as revision leads because scarring caused by a primary lead may inhibit placement of a percutaneous revision lead. As such, there is a need for paddle leads deployable from a minimally invasive surgical approach. It is with these observations in mind, among others, that various aspects of the present disclosure were conceived and developed.
SUMMARYImplementations described and claimed herein address the foregoing problems, among others, by providing dorsal root ganglia stimulation leads and methods of implanting the same. In one implementation, a paddle body extends between a proximal end and a distal end. A lead body extends from the proximal end forming a paddle lead. An electrode array is disposed on at least one surface of the paddle body. The electrode array has one or more electrode contacts arranged in an electrode array configuration. A tapered distal tip is formed by the paddle body tapering in width toward the distal end. The tapered distal tip is shaped for surgical placement of the paddle body below vertebral lamina dorsal to the dorsal root ganglion following a medial laminectomy and ligament removal. The surgical placement orients the electrode array for the electrical stimulation of the dorsal root ganglion.
In another implementation, a paddle body extends between a proximal end and a distal end, and a lead body extends from the proximal end. An electrode array is disposed on at least one surface of the paddle body. The electrode array has one or more electrode contacts arranged in a two-dimensional electrode array configuration forming an asymmetrical paddle lead with the electrical stimulation focused in a single direction within a target area of the dorsal root ganglion. A living hinge is formed by the paddle body extending from a first side to a first hinge and from a second side to a second hinge. The first and second hinges each form a joint configured to bend the paddle body along a contour to cradle the dorsal root ganglion.
In still another implementation, a paddle body extends between a proximal end and a distal end. A lead body extends from the proximal end forming a paddle lead. An electrode array is disposed on at least one surface of the paddle body. The electrode array has one or more electrode contacts arranged in a two-dimensional electrode array configuration. A suture loop configuration has one or more suture loops for suture guided deployment of the paddle lead.
Other implementations are also described and recited herein. Further, while multiple implementations are disclosed, still other implementations of the presently disclosed technology will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative implementations of the presently disclosed technology. As will be realized, the presently disclosed technology is capable of modifications in various aspects, all without departing from the spirit and scope of the presently disclosed technology. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not limiting.
Aspects of the present disclosure involve paddle leads for dorsal root ganglia (DRG) stimulation and methods of implanting the same. Generally, a paddle lead is implanted in a target area of a patient through access to the foraminal space above the DRG using a minimally invasive approach. In one aspect, the paddle lead has a small profile facilitating deployment into the neuroforamen dorsal to the DRG below the vertebral lamina. The small profile may include, for example, a thin cross-section facilitating placement below the lamina and resisting displacement of the DRG during implantation. The paddle lead profile would thus be adapted for deployment in a DRG target area, such as lumbar or thoracic neuroforamen caudal to the pedicles. A paddle body of the paddle lead may be further adapted for implantation in the target space. For example, the paddle body may include a living hinge and/or have a contoured profile for flexible placement and functionality within the target space. Wires or formable plates may be used to maintain the shape of the paddle body and/or other portions of the paddle lead. To further facilitate placement as well as resist migration once deployed, the paddle lead may include a suture loop configuration having one or more suture holes for securing the paddle lead to bone anchors, tissue, and/or the like within the target space.
In one aspect, the paddle lead includes an electrode array with a directionality to focus the stimulation. The directionality, for example, may focus the stimulation in one direction to overcome stimulation loss caused by scar tissue present in the target area. The directionality may further reduce power consumption by the paddle lead. The electrode array includes one or more electrode contacts arranged to maximize programming potential for DRG stimulation. The electrode array may have a two-dimensional (2D) configuration pattern, increasing subdermatormal specificity. The asymmetrical design of the paddle lead improves stability, for example, in the left or right neuroforamen.
To begin a detailed description of treatment to a patient 100 for a medical condition, such as chronic pain, through the application of electrical stimulation to a target area, reference is made to
In one implementation, the paddle lead 114 has a lead body extending proximally from a paddle body to the power source 116. The power source 116 delivers power to an electrode array disposed on or along the paddle body, which is implanted in the target area of the patient 100. The electrode array of the paddle lead 114 includes an electrode configuration pattern, such as a 2D (i.e., nonlinear) configuration pattern, to deliver electrical stimulation to a DRG in the target area of the patient 100. As described herein, the paddle lead 114 may provide a directionality of the electrical stimulation. In one implementation, the directionality of the electrode array of the paddle lead 114 focuses the stimulation in one direction to overcome stimulation loss caused by scar tissue present in the target area of the patient 100. Such scar tissue may be present in the target area, for example, due to the previous implantation of a primary lead. The directionality may further reduce power output by the power source 116 and consumed by the paddle lead 114.
The paddle body of the paddle lead 114 may further be sized and shaped to facilitate navigating the spinal anatomy of the patient 100 during deployment of the paddle lead 114 and once implanted, to provide a flexibility of the paddle lead 114 during electrical stimulation. For a non-limiting example of a percutaneous or other minimally invasive deployment of the paddle lead 114 for SCS treatment, reference is made to
Turning first to
Referring to
As shown in
The delivery tool 130 may be inserted at an angle. In one implementation, as can be understood from
Referring to
Turning to
Dorsal horns 158 and 160 connect the spinal levels. For example, a second spinal level 144 is connected to a first spinal level 146 via an ascending pathway 150, and the second spinal level 144 is connected to a third spinal level 148 via a descending pathway 152. Application of electrical stimulation to the DRG 142 in the second spinal level 144 may be used to block signals progressing upstream from the second spinal level 144 to the ascending pathway 150. Modulation applied to portions of the second spinal level 144 may further be used to block the neuron pathways from the first spinal level 146 or third spinal level 148 from reaching the brain of the patient 100, thereby blocking intrasegment pain pathways.
In one implementation, the paddle lead 114 is implanted into neuroforamen dorsal to the DRG 142 of one of the spinal levels (e.g., the second spinal level 144) of the patient 100, with the foraminal space above the DRG 142 accessed from a minimally invasive surgical approach for implantation. A medial laminectomy is performed to remove lateral laminar and ligament to access the foraminal space. To assist dissection, a spacer having a contourable body may be placed and the paddle lead 114 deployed into the lumbar or thoracic neuroforamen caudal to the pedicles. The paddle lead 114 is positioned in the target area over the DRG 142. In one implementation, the paddle lead 114 includes a suture loop configuration, permitting the paddle lead 114 to be pulled through the spinal anatomy of the patient 100 into the target area using one or more sutures. In addition to this suture assisted deployment, the paddle lead 114 may be secured over the DRG 142 in the target area using the suture loop configuration.
The paddle lead 114 has a thin, compact, low profile, shaped to facilitate minimally invasive surgical placement. In one implementation, a distal tip of the paddle lead 114 tapers permitting placement over the DRG 142. Alternatively or additionally, the paddle body of the paddle lead 114 may have a living hinge creating a contouring of the paddle body to hug or otherwise provide substantially continuous contact with the DRG 142. The paddle lead 114 may be made from a contourable material for pliable shaping of the paddle body. Further, the paddle lead 114 may include formable elements, such as wire(s) and/or coil(s) to enhance and maintain the contouring.
The electrode array 140 has one or more electrode contacts arranged in an electrode array configuration to create an electrical field optimized for stimulation of the DRG 142. In one implementation, the electrode array 140 includes a 2D configuration pattern, enhancing specificity and selectivity. For example, the electrode array configuration may include electrodes arranged in a four by two by two pattern, a six by three by three pattern, a two by two pattern, or the like. The electrode array 140 may be configured for high frequency and/or burst stimulation patterns.
Turning first to
The paddle lead 200 has a thin, compact, low profile, as discussed herein. In one example implementation, the paddle lead 200 has a length 216 of approximately 2.865 inches; the paddle body 206 has a width 214 of approximately 0.275 inches; and the lead body 212 has a width 218 of approximately 0.100 inches. Other dimensions are contemplated.
A lead body assembly 312 extends from the proximal end 304 of the paddle body 306. The lead body assembly 312 may have one or more elongated bodies that are fixed, contourable, flexible, and/or rigid. In one implementation, the lead body assembly 312 has one or more conductive wires or coils connected to trace conductors 310 via a lead connector 316, which may be made, for example, from molded silicone or other polymers. Each of the trace conductors 310 electrically connects a corresponding electrode contact 308 in an electrode array to supply electrical energy for stimulation of the DRG 142.
The electrode array includes the electrode contacts 308 arranged in a 2D configuration pattern on a surface of the paddle body 306, such that the paddle lead 300 is asymmetrical. The electrode contacts 308 may have varying sizes configured to optimize stimulation of the DRG 142. For example, the electrode contacts 308 may be approximately nine micron thick. In one implementation, the paddle body 306 includes a conformable plating 318 deposited on a base 320 opposite a surface on which the electrode contacts 308 and the trace conductors 310 are disposed. The conformable plating 318 may be used to achieve and maintain a profile shape of the paddle body 306. The base 320 may be made from a variety of biocompatible materials, including, but not limited to, Kapton or other polyimides. Again, the paddle lead 300 has a thin, compact, low profile, as shown in
For suture assisted deployment of the paddle lead 300, in one implementation, a suture loop configuration has one or more suture holes 314 defined in or disposed along the paddle body 306, the lead connector 316, and/or the lead body assembly 312. For example, as shown in
A lead body 412 extends from the neck 418. In one implementation, the lead body 412 has one or more conductive wires or coils connected to trace conductors 410 via a lead connector 416, which may be made, for example, from molded silicone or other polymers. Each of the trace conductors 410 electrically connects a corresponding electrode contact 408 in an electrode array to supply electrical energy for stimulation of the DRG 142.
The electrode array includes the electrode contacts 408 arranged in a 2D configuration pattern on a surface of the paddle body 406, such that the paddle lead 400 is asymmetrical. Again, the paddle lead 400 has a thin, compact, low profile, as shown in
For suture assisted deployment of the paddle lead 400, in one implementation, a suture loop configuration has one or more suture holes 414 defined in or disposed along the paddle body 406, the neck 418, the lead connector 416, and/or the lead body 412. For example, as shown in
As described herein, the paddle lead 114 includes an electrode array 140 for focused stimulation of the DRG 142. For examples of various non-limiting configurations 500-504 of the electrode array 140, reference is made to
The electrode contacts 512 form the electrode array 140 arranged in an electrode array configuration, such as the electrode array configurations 500, 502, or 504. The electrode array configuration 500 includes eight electrode contacts 512 arranged in a four-by-two-by-two pattern. The electrode array configuration 502 includes twelve electrode contacts 512. In one implementation, the electrode contacts 512 are arranged in a six-by-three-by-three pattern in the electrode array configuration 502. Finally, the electrode array configuration 504 includes four electrodes arranged in a two-by-two pattern. It will be appreciated that other electrode array configurations are contemplated.
The paddle lead 114 may further have a variety of shapes and sizes to provide a thin, compact, low profile. For examples 600-604 of the dimensions of the paddle lead 114, reference is made to
Each of the paddle leads 600-604 has a thin, compact, low profile. In one implementation, the paddle lead 600 has a length of approximately 2.8 to 3.5 inches, and the paddle body 610 has a width of approximately 2.0 to 3.4 inches. The paddle body 610 of the paddle lead 600 is sized to accommodate approximately eight electrode contacts 612. Similarly, the paddle leads 602 and 604 may be sized to accommodate approximately twelve electrode contacts 612. In one implementation, the paddle leads 604 and 606 have a length of approximately 3.0 to 3.8 inches, and the paddle body 610 of the paddle leads 602 and 604 has a width of approximately 2.3 to 3.4 inches. The paddle body 610 of the paddle lead 602 may taper in width distally to form a tapered distal tip.
It will be appreciated that the paddle leads 600-604 may have a variety of dimensions forming the thin, compact, low profile. For example, the paddle leads 600-604 may have a length of approximately 30 mm, 45 mm, 60 mm, 75 mm, 90 mm, or similar lengths. Further, the paddle body 610 and/or the lead body 614 may have a thickness ranging from approximately 0.020 inches to 0.055 inches.
The electrode contacts 612 may also be arranged in various electrode array configurations with different dimensions. The electrode array configurations may include any number of electrode contacts 612, for example, four, six, eight, twelve, sixteen, or the like. Each of the electrode contacts 612 may have a length ranging from approximately 2 mm to 4 mm. In some specific examples, the length of the electrode contacts 612 is approximately 1.5 mm, 2 mm, 2.5 mm, or 3 mm. The electrode contacts 612 may further have a longitudinal spacing ranging from approximately 1 mm to 4 mm depending on the electrode array configuration. For example, the longitudinal spacing may be approximately 1 mm, 2 mm, 3 mm, 4 mm, or the like. The electrode array configuration may have an array length ranging from approximately 10 mm to 24 mm, again depending on the electrode array configuration.
As can be understood from
As shown in
The suture loop configurations 704-708 include may each include suture holes 718 disposed along the lead body 720. In one implementation, the suture loop configurations 704-708 each include a first set of suture holes 718 disposed near the proximal end 712 of the paddle body 714 and a second set of suture holes 718 disposed proximal to the first set along the lead body 720.
Turning to
In one implementation, the living hinge 800 includes a first hinge 812 and a second hinge 814, each extending a long a length of the paddle body 806 from the distal end 802 to the proximal end 804. The first hinge 812 is disposed between the first and second columns of electrode contacts 808, and the second hinge 814 is disposed between the second and third columns of electrode contacts 808. The first and second hinges 812 and 814 each form a joint in the paddle body 806 along which the paddle body 806 is bendable to navigate the anatomy of the target area in the patient 100 and to cradle the DRG 142.
As can be understood from
For suture assisted deployment of the paddle lead 1000, in one implementation, a suture loop configuration has one or more suture holes 1016 defined in or disposed along the paddle body 1008, and one or more suture holes 1018 defined in or disposed along the neck 1010. For example, as shown in
One or more portions of the paddle lead 114 may taper to facilitate deployment. As can be understood from
Another example paddle lead 1200 shown in
In one implementation, the paddle body 1206 is contourable, such that the paddle body 1206 may shaped to extend along a curve between a first side 1212 and a second side 1214. The shape formed by the paddle body 1206 mirrors a shape of the DRG 142 to facilitate contact by the electrode contacts 1210 with the DRG 142 for stimulation. The shape of the paddle body 1206 may be maintained, for example, using wires or formable plates. Further, in some implementations, the shape of the paddle body 1206 may be manipulated during deployment to position the electrode contacts 1210 for stimulation of the DRG 142.
As discussed herein, a suture loop configuration may be used to facilitate deployment.
One or more electrode contacts 1410 are disposed on at least one surface of the paddle body 1406 and in electrical communication with the power source 116 via a lead body 1408. The electrode contacts 1410 may have varying dimensions and spacing. For example, the electrode contacts 1410 may be approximately 2-3 mm in size with spacing of approximately 1.5-3 mm. The array formed by the electrode contacts 1410 may have a length of approximately 30-45 mm and a width of approximately 2-4 mm.
The electrode contacts 1410 may be arranged in various electrode array configurations. For example, as shown in
In one implementation, the living hinge includes a first hinge 1418 and a second hinge 1420, each extending a long a length of the paddle body 1406 from the distal end 1402 to the proximal end 1404. The first hinge 1418 is disposed between the first and second columns of electrode contacts 1410, and the second hinge 1420 is disposed between the second and third columns of electrode contacts 1410. The first and second hinges 1418 and 1420 each form a joint in the paddle body 1406 along which the paddle body 1406 is bendable to navigate the anatomy of the target area in the patient 100 and to cradle the DRG 142. More particularly, the paddle body 1406 extends from a first side 1414 to the first hinge 1418 and from a second side 1416 to the second hinge 1420, thereby bending around a contour of the DRG 142 as shown in
As described herein, the paddle lead 114 may include a tapered end to advance surgical placement.
In one implementation, the paddle body 1506 tapers distally in width towards the distal end 1502 to form a tapered distal tip. The tapered distal tip may have a variety of shapes. For example, the tapered distal tip may have a rounded edge, such that the width of the paddle body 1506 tapers smoothly along a curve toward the distal end 1502. The paddle body 1506 may further taper proximally at the proximal end 1504 towards the lead body 1508.
To further assist surgical placement, the paddle body 1506 may include a suture loop configuration with one or more suture holes 1510 defined therein. In one implementation, a first set of the suture holes 1510 is disposed on a periphery of the paddle body 1506 where the width begins to taper into the tapered distal tip. A second set of the suture holes 1510 is disposed on the periphery of the paddle body 1506 proximal to the first set of the suture holes 1510. In one implementation, the second set of the suture holes 1510 is disposed at the proximal end 1504 where the width begins to taper proximally to connect with the lead body 1508.
Turning next to
Similarly, turning to
To further assist surgical placement, the paddle body 1706 may include a suture loop configuration with one or more suture holes 1710 defined therein. In one implementation, the suture loop configuration includes a first set of the suture holes 1710 is disposed on a periphery of the paddle body 1706 where the width begins to taper into the tapered distal tip. A second set of the suture holes 1710 is disposed on the periphery of the paddle body 1706 proximal to the first set of the suture holes 1710. In one implementation, the second set of the suture holes 1710 is disposed at the proximal end 1704 where the width begins to taper proximally to connect with the lead body 1708.
Various other modifications and additions can be made to the exemplary implementations discussed without departing from the spirit and scope of the presently disclosed technology. For example, while the embodiments described above refer to particular features, the scope of this disclosure also includes implementations having different combinations of features and implementations that do not include all of the described features. Accordingly, the scope of the presently disclosed technology is intended to embrace all such alternatives, modifications, and variations together with all equivalents thereof.
Claims
1. A system for electrical stimulation of a dorsal root ganglion, the system comprising:
- a paddle body extending between a proximal end and a distal end;
- a lead body extending from the proximal end forming a paddle lead;
- an electrode array disposed on at least one surface of the paddle body, the electrode array having one or more electrode contacts arranged in an electrode array configuration; and
- a tapered distal tip formed by the paddle body tapering in width toward the distal end, the tapered distal tip shaped for surgical placement of the paddle body below vertebral lamina dorsal to the dorsal root ganglion following a medial laminectomy and ligament removal, the surgical placement orienting the electrode array for the electrical stimulation of the dorsal root ganglion.
2. The system of claim 1, wherein the surgical placement includes deploying the paddle body into one of lumbar or thoracic neuroformen caudal to pedicles.
3. The system of claim 1, wherein the paddle lead is deployed using a delivery tool having a sheath with a spatula shaped distal tip.
4. The system of claim 3, wherein the spatula shaped distal tip of the sheath is between ten and thirty percent larger in size than the paddle body.
5. The system of claim 1, wherein the tapered distal tip has a rounded shape or a pointed shape.
6. The system of claim 1, wherein the paddle body is configured to cradle the dorsal root ganglion.
7. The system of claim 6, wherein the paddle body has a contoured shape extending along a curve from a first end of the paddle body to a second end of the paddle body to cradle the dorsal root ganglion.
8. The system of claim 7, wherein the contoured shape of the paddle body is maintained with one or more formable elements including at least one of one or more wires, one or more plates, or one or more coils.
9. The system of claim 6, wherein the paddle body includes a living hinge with the paddle body extending from a first side to a first hinge and from a second side to a second hinge, the first and second hinges each forming a joint configured to bend the paddle body along a contour to cradle the dorsal root ganglion.
10. A system for electrical stimulation of a dorsal root ganglion, the system comprising:
- a paddle body extending between a proximal end and a distal end;
- a lead body extending from the proximal end;
- an electrode array disposed on at least one surface of the paddle body, the electrode array having one or more electrode contacts arranged in a two-dimensional electrode array configuration forming an asymmetrical paddle lead with the electrical stimulation focused in a single direction within a target area of the dorsal root ganglion; and
- a living hinge formed by the paddle body extending from a first side to a first hinge and from a second side to a second hinge, the first and second hinges each forming a joint configured to bend the paddle body along a contour to cradle the dorsal root ganglion.
11. The system of claim 10, wherein the single direction is configured to overcome stimulation loss caused by scar tissue present in the target area.
12. The system of claim 10, wherein the electrode array is configured for at least one of high frequency or burst stimulation patterns.
13. The system of claim 10, wherein the two-dimensional electrode array configuration includes a four-by-two-by-two pattern; a six-by-three-by-three pattern; or a two-by-two pattern.
14. The system of claim 10, wherein the two-dimensional electrode array configuration includes the one or more electrode contacts arranged in a nonlinear pattern with a plurality of columns.
15. The system of claim 14, wherein the plurality of columns includes a first column, a second column, and a third column and the first hinge is disposed between the first column and the second column and the second hinge is disposed between the second column and the third column.
16. The system of claim 10, wherein the one or more electrode contacts each have a size ranging from two to three millimeters.
17. The system of claim 10, wherein the electrode array has a length ranging from thirty to forty-five millimeters and a width ranging from two to four millimeters.
18. A system for electrical stimulation of a dorsal root ganglion, the system comprising:
- a paddle body extending between a proximal end and a distal end;
- a lead body extending from the proximal end forming a paddle lead;
- an electrode array disposed on at least one surface of the paddle body, the electrode array having one or more electrode contacts arranged in a two-dimensional electrode array configuration; and
- a suture loop configuration having one or more suture loops for suture guided deployment of the paddle lead.
19. The system of claim 18, wherein the one or more suture loops are disposed on the paddle body relative to electrical pathways of the one or more electrode contacts.
20. The system of claim 18, wherein the one or more suture loops are disposed on at least one of a distal tip of the paddle body, the paddle body, a neck, or the lead body.
Type: Application
Filed: Oct 25, 2016
Publication Date: Apr 26, 2018
Inventor: Timothy R. Deer (Charleston, WV)
Application Number: 15/333,999