Patent Description:
Implantable electrical stimulation systems have proven therapeutic in a variety of diseases and disorders. For example, spinal cord stimulation systems have been used as a therapeutic modality for the treatment of chronic pain syndromes. Peripheral nerve stimulation has been used to treat chronic pain syndrome and incontinence, with a number of other applications under investigation. Functional electrical stimulation systems have been applied to restore some functionality to paralyzed extremities in spinal cord injury patients. Stimulation of the brain, such as deep brain stimulation, can be used to treat a variety of diseases or disorders.

Stimulators have been developed to provide therapy for a variety of treatments. A stimulator can include a control module (with a pulse generator), one or more leads, and an array of stimulator electrodes on each lead. The stimulator electrodes are in contact with or near the nerves, muscles, or other tissue to be stimulated. The pulse generator in the control module generates electrical pulses that are delivered by the electrodes to body tissue.

<CIT> discloses an electrode assembly to be installed on a patient's nerve which has a circum-neural carrier with a split circumferential configuration longitudinally attached to a lead at the distal end thereof.

<CIT> describes devices, systems, and methods for recording, and/or stimulation, and/or blocking of a nerve make use of a molded nerve cuff electrode. One or more electrodes are positioned in one or more frames within a casing of the cuff electrode.

<CIT> discloses a nerve stimulation system including at least one nerve interface device. The device includes a cuff portion having an assembled position in which the cuff portion forms at least part of a passageway for receiving a nerve along a longitudinal axis passing through the passage-way; and first and second rings of electrodes mounted on the cuff portion, each ring of electrodes including a plurality of electrodes, and wherein each electrode in the first ring has a corresponding longitudinally-aligned electrode in the second ring so as to form a plurality of pairs of electrodes spaced apart from each other along the longitudinal axis.

<CIT> discloses an electrode device configured to be coupled to a parasympathetic site of a subject. A control unit is configured to drive the electrode device to apply a current in bursts of one or more pulses.

<CIT> describes an electrode lead comprising an elongated lead body, at least one lead connector terminal affixed to the proximal end of the lead body, and an electrically insulative cuff body affixed to the distal end of the lead body. The cuffbody is configured for being circumferentially disposed around a nerve. The cuffbody comprises cutouts, slits, a wrinkled portion, a thin stretchable portion, and/or a serpentine strap, which increases that increase the expandability of the cuff body when disposed around the nerve. The electrode lead further comprises at least one electrode contact affixed to the cuff body, and at least one electrical conductor extending through the lead body between the at least one lead connector terminal and the electrode contact(s).

One aspect is an electrical stimulation lead that includes a cuff having a cuff body having an exterior surface, an interior surface, and a circumference; longitudinal electrodes disposed on the interior surface of the cuff body, wherein each of the longitudinal electrodes has an aspect ratio of length/width of at least <NUM>, wherein the longitudinal electrodes are divided into at least one set with each set including at least sixteen of the longitudinal electrodes spaced apart from each other in a circumferential arrangement round the circumference of the cuff body; and a longitudinal slit extending through the cuff body and further extending along an entire length of the cuff body, the longitudinal slit operable to receive a portion of a target nerve from a region outside of the cuff to within the cuff body. The electrical stimulation lead also includes a lead body coupled to the cuff and conductors extending through the lead body and the cuff with the conductors electrically coupled to the longitudinal electrodes.

In at least some aspects, the aspect ratio of each of the longitudinal electrodes is at least <NUM>. In at least some aspects, each of the longitudinal electrodes has a width of no more than <NUM>. In at least some aspects, each of the longitudinal electrodes has a length of at least <NUM>. In at least some aspects, each of the at least one set includes at least <NUM> of the longitudinal electrodes spaced apart from each other in the circumferential arrangement around the circumference of the cuff body.

In at least some aspects, the cuff further includes at least one radial electrode extending around at least <NUM>% of the circumference of the cuff body. In at least some aspects, the cuff further includes at least one set of radial electrodes, wherein each set of the radial electrodes includes at least two of the radial electrodes in a circumferential arrangement extending around at least <NUM>% of the circumference of the cuff body.

Another aspect is an electrical stimulation lead that includes a cuff having a cuff body having an exterior surface, an interior surface, and a circumference; longitudinal electrodes disposed on the interior surface of the cuff body, wherein each of the longitudinal electrodes has a width of no more than <NUM>, wherein the longitudinal electrodes are divided into at least one set with each set including at least sixteen of the longitudinal electrodes spaced apart from each other in a circumferential arrangement round the circumference of the cuff body; and a longitudinal slit extending through the cuff body and further extending along an entire length of the cuff body, the longitudinal slit operable to receive a portion of a target nerve from a region outside of the cuff to within the cuff body. The electrical stimulation lead also includes a lead body coupled to the cuff and conductors extending through the lead body and the cuff with the conductors electrically coupled to the longitudinal electrodes.

In at least some aspects, the aspect ratio of each of the longitudinal electrodes is at least <NUM>. In at least some aspects, each of the longitudinal electrodes has a length of at least <NUM>. In at least some aspects, each of the at least one set includes at least <NUM> of the longitudinal electrodes spaced apart from each other in the circumferential arrangement round the circumference of the cuff body.

A further aspect is an electrical stimulation lead that includes a cuff having a cuff body having an exterior surface, an interior surface, and a circumference; longitudinal electrodes disposed on the interior surface of the cuff body, wherein the longitudinal electrodes are divided into at least one set with each set including at least sixteen or thirty-two of the longitudinal electrodes spaced apart from each other in a circumferential arrangement round the circumference of the cuff body; one or more radial electrodes extending solely, or in a combination of two or more of the radial electrodes (for example, when there are two or more radial electrodes), around at least <NUM>% of the circumference of the cuff body; and a longitudinal slit extending through the cuff body and further extending along an entire length of the cuff body, the longitudinal slit operable to receive a portion of a target nerve from a region outside of the cuff to within the cuff body. The electrical stimulation lead also includes a lead body coupled to the cuff and conductors extending through the lead body and the cuff with conductors electrically coupled to the longitudinal and radial electrodes.

In at least some aspects, the aspect ratio of each of the longitudinal electrodes is at least <NUM>. In at least some aspects, each of the longitudinal electrodes has a width of no more than <NUM>. In at least some aspects, each of the longitudinal electrodes has a length of at least <NUM>. In at least some aspects, each of the at least one set includes at least <NUM> of the longitudinal electrodes spaced apart from each other in the circumferential arrangement round the circumference of the cuff body.

In at least some aspects, the cuff further includes at least two sets of the radial electrodes, wherein each set of the radial electrodes includes at least one of the radial electrodes extending around at least <NUM>% of the circumference of the cuff body. In at least some aspects, at least one of the sets of radial electrodes includes at least two of the radial electrodes extending, in combination, around at least <NUM>% the circumference of the cuff body. In at least some aspects, the cuff further includes a cushioning layer disposed over the interior surface of the cuff body.

Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following drawings. In the drawings, like reference numerals refer to like parts throughout the various figures unless otherwise specified.

The present invention is directed to the area of implantable electrical stimulation systems and methods of making and using the systems. The present invention is also directed to implantable electrical stimulation cuff devices, as well as methods of making and using the same.

Suitable implantable electrical stimulation systems include, but are not limited to, a least one lead with one or more electrodes disposed along a distal end of the lead. Leads include, for example, percutaneous leads, paddle leads, and cuff leads. Examples of electrical stimulation systems with leads are found in, for example, <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>;<CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>; and <CIT> and <CIT>.

<FIG> illustrates schematically one embodiment of an electrical stimulation system <NUM>. The electrical stimulation system includes a control module (e.g., a stimulator or pulse generator) <NUM> and a lead <NUM> coupleable to the control module <NUM>. The lead <NUM> includes a mount <NUM> and a cuff <NUM>. The lead <NUM> includes one or more lead bodies <NUM>, an array of electrodes <NUM>, such as electrode <NUM>, and an array of terminals (e.g., <NUM> in <FIG>) disposed within the cuff <NUM> attached to the one or more lead bodies <NUM>. In at least some embodiments, the lead is isodiametric along at least a portion of the longitudinal length of the lead body <NUM>. <FIG> illustrates one lead <NUM> coupled to a control module <NUM>. Other embodiments may include two, three, four, or more leads <NUM> coupled to the control module <NUM>. In yet other embodiments, a lead <NUM> may be coupled to multiple control modules <NUM>. For example, a lead with <NUM> electrodes may be coupled to two control modules <NUM> that are capable of handling <NUM> electrodes each.

The lead <NUM> can be coupled to the control module <NUM> in any suitable manner. In at least some embodiments, the lead <NUM> couples directly to the control module <NUM>. In at least some other embodiments, the lead <NUM> couples to the control module <NUM> via one or more intermediate devices (<NUM> in <FIG>). For example, in at least some embodiments one or more lead extensions <NUM> (see e.g., <FIG>) can be disposed between the lead <NUM> and the control module <NUM> to extend the distance between the lead <NUM> and the control module <NUM>. Other intermediate devices may be used in addition to, or in lieu of, one or more lead extensions including, for example, a splitter, an adaptor, or the like or combinations thereof. It will be understood that, in the case where the electrical stimulation system <NUM> includes multiple elongated devices disposed between the lead <NUM> and the control module <NUM>, the intermediate devices may be configured into any suitable arrangement.

In <FIG>, the electrical stimulation system <NUM> is shown having a splitter <NUM> configured and arranged for facilitating coupling of the lead <NUM> to the control module <NUM>. The splitter <NUM> includes a splitter connector <NUM> configured to couple to a proximal end of the lead <NUM>, and one or more proximal tails 109a and 109b configured and arranged to couple to the control module <NUM> (or another splitter, a lead extension, an adaptor, or the like). The splitter <NUM> and splitter connector <NUM> may be part of the lead <NUM> or may be a separate component that attaches to the lead.

The control module <NUM> typically includes a connector housing <NUM> and a sealed electronics housing <NUM>. Stimulation circuitry <NUM> and an optional power source <NUM> are disposed in the electronics housing <NUM>. A control module connector <NUM> is disposed in the connector housing <NUM>. The control module connector <NUM> is configured and arranged to make an electrical connection between the lead <NUM> and the stimulation circuitry <NUM> of the control module <NUM>.

The electrical stimulation system or components of the electrical stimulation system, including the lead body <NUM> and the control module <NUM>, are typically implanted into the body of a patient. The electrical stimulation system can be used for a variety of applications including, but not limited to, brain stimulation, neural stimulation, spinal cord stimulation, muscle stimulation, and the like.

The lead body <NUM> can be made of, for example, a non-conductive, biocompatible material such as, for example, silicone, polyurethane, polyetheretherketone ("PEEK"), epoxy, and the like or combinations thereof. The lead body <NUM> may be formed in the desired shape by any process including, for example, molding (including injection molding), casting, and the like. The non-conductive material typically extends from the distal end of the lead body <NUM> to the proximal end of the lead body <NUM>.

Terminals (e.g., <NUM> in <FIG>) are typically disposed along the proximal end of the lead body <NUM> of the electrical stimulation system <NUM> (as well as any splitters, lead extensions, adaptors, or the like) for electrical connection to corresponding connector contacts (e.g., <NUM> and <NUM> in <FIG>). The connector contacts are disposed in connectors (e.g., <NUM> in <FIG>; and <NUM> in <FIG>) which, in turn, are disposed on, for example, the control module <NUM> (or a lead extension, a splitter, an adaptor, or the like). Electrically conductive wires <NUM>, cables, or the like (only one of which is shown in <FIG>) extend from the terminals to the electrodes <NUM>. Typically, one or more electrodes <NUM> are electrically coupled to each terminal. In at least some embodiments, each terminal is only connected to one electrode <NUM>.

The electrically conductive wires ("conductors") <NUM> (only one of which is illustrated in <FIG> for clarity) may be embedded in the non-conductive material of the lead body <NUM> or can be disposed in one or more lumens (not shown) extending along the lead body <NUM>. In some embodiments, there is an individual lumen for each conductor. In other embodiments, two or more conductors extend through a lumen. There may also be one or more lumens (not shown) that open at, or near, the proximal end of the lead body <NUM>, for example, for inserting a stylet to facilitate placement of the lead body <NUM> within a body of a patient. Additionally, there may be one or more lumens (not shown) that open at, or near, the distal end of the lead body <NUM>, for example, for infusion of drugs or medication into the site of implantation of the lead body <NUM>. In at least one embodiment, the one or more lumens are flushed continually, or on a regular basis, with saline, epidural fluid, or the like. In at least some embodiments, the one or more lumens are permanently or removably sealable at the distal end.

<FIG> also illustrates a mount <NUM>, part of the lead body <NUM>, coupled to cuff <NUM>. The conductors <NUM> (only one of which is illustrated in <FIG> for clarity) from within the lead body <NUM> are received in the mount <NUM>, which in turn is attached to the cuff <NUM> such that each conductor passes through the mount <NUM> for a direct electrical connection with one of the electrodes <NUM> (e.g., one conductor is electrically connected with one electrode and so on). The mount <NUM> may be attached using a variety of means such as, but not limited to, molding or adhering the mount <NUM> to the cuff <NUM>. In other embodiments, the conductors <NUM> from within the lead body <NUM> are electrically coupled to the electrodes <NUM> using jumper, intermediate or transition wires from the lead body <NUM> to the electrodes <NUM>.

The mount <NUM> can be offset from the cuff <NUM>, as illustrated in <FIG>, or in-line with the cuff or in any other suitable arrangement. Examples of cuff leads <NUM> can be found at <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>; and <CIT> and <CIT>.

<FIG> is a schematic side view of one embodiment of a proximal end of one or more elongated devices <NUM> configured and arranged for coupling to one embodiment of the control module connector <NUM>. The one or more elongated devices may include, for example, the lead body <NUM>, one or more intermediate devices (e.g., the lead extension <NUM> of <FIG>, an adaptor, or the like or combinations thereof), or a combination thereof. <FIG> illustrates two elongated devices <NUM> coupled to the control module <NUM>. These two elongated devices <NUM> can be two tails as illustrated in <FIG> or two different leads or any other combination of elongated devices.

The control module connector <NUM> defines at least one port into which a proximal end of the elongated device <NUM> can be inserted, as shown by directional arrow <NUM>. In <FIG> (and in other figures), the connector housing <NUM> is shown having two ports 204a and 204b. The connector housing <NUM> can define any suitable number of ports including, for example, one, two, three, four, five, six, seven, eight, or more ports.

The control module connector <NUM> also includes a plurality of connector contacts, such as connector contact <NUM>, disposed within each port 204a and 204b. When the elongated device <NUM> is inserted into the ports 204a and 204b, the connector contacts <NUM> can be aligned with a plurality of terminals <NUM> disposed along the proximal end(s) of the elongated device(s) <NUM> to electrically couple the control module <NUM> to the electrodes (<NUM> of <FIG>) disposed at a distal end of the lead <NUM>. Examples of connectors in control modules are found in, for example, <CIT> and <CIT>.

<FIG> is a schematic side view of another embodiment of the electrical stimulation system <NUM>. The electrical stimulation system <NUM> includes a lead extension <NUM> that is configured and arranged to couple one or more elongated devices <NUM> (e.g., the lead body <NUM>, an adaptor, another lead extension, or the like or combinations thereof) to the control module <NUM>. In <FIG>, the lead extension <NUM> is shown coupled to a single port <NUM> defined in the control module connector <NUM>. Additionally, the lead extension <NUM> is shown configured and arranged to couple to a single elongated device <NUM>. In alternate embodiments, the lead extension <NUM> is configured and arranged to couple to multiple ports <NUM> defined in the control module connector <NUM>, or to receive multiple elongated devices <NUM>, or both.

A lead extension connector <NUM> is disposed on the lead extension <NUM>. In <FIG>, the lead extension connector <NUM> is shown disposed at a distal end <NUM> of the lead extension <NUM>. The lead extension connector <NUM> includes a connector housing <NUM>. The connector housing <NUM> defines at least one port <NUM> into which terminals <NUM> of the elongated device <NUM> can be inserted, as shown by directional arrow <NUM>. The connector housing <NUM> also includes a plurality of connector contacts, such as connector contact <NUM>. When the elongated device <NUM> is inserted into the port <NUM>, the connector contacts <NUM> disposed in the connector housing <NUM> can be aligned with the terminals <NUM> of the elongated device <NUM> to electrically couple the lead extension <NUM> to the electrodes (<NUM> of <FIG>) disposed along the lead (<NUM> in <FIG>).

In at least some embodiments, the proximal end of the lead extension <NUM> is similarly configured and arranged as a proximal end of the lead <NUM> (or other elongated device <NUM>). The lead extension <NUM> may include a plurality of electrically conductive wires (not shown) that electrically couple the connector contacts <NUM> to a proximal end <NUM> of the lead extension <NUM> that is opposite to the distal end <NUM>. In at least some embodiments, the conductive wires disposed in the lead extension <NUM> can be electrically coupled to a plurality of terminals (not shown) disposed along the proximal end <NUM> of the lead extension <NUM>. In at least some embodiments, the proximal end <NUM> of the lead extension <NUM> is configured and arranged for insertion into a connector disposed in another lead extension (or another intermediate device). In other embodiments (and as shown in <FIG>), the proximal end <NUM> of the lead extension <NUM> is configured and arranged for insertion into the control module connector <NUM>.

Conventional cuff leads include a cuff that wraps around a portion of a nerve with one or more electrodes arranged on the cuff. In many conventional cuff leads, the individual electrodes also wrap around at least a portion of the circumference of a nerve in a radial wrap arrangement. The radial wrap arrangement of the electrodes typically results in stimulation of a circumferential region of the nerve.

However, a nerve is not a monolithic biological construct, but, instead, the nerve is made of many fibers (which can be arranged in groups) that extend longitudinally along the nerve. <FIG> is a cross-section of a portion of the vagus nerve <NUM> illustrating the many fibers <NUM> within the nerve. In some instances, it may be desirable to stimulate only one fiber or a group of fibers.

Electrodes in a radial wrap arrangement generally cannot selectively stimulate fibers or groups of fibers, but, instead, such electrodes stimulate many fibers due to extending around the circumference of the nerve. In addition, such electrodes may produce unwanted side effects as multiple nerve fibers are stimulated. For example, a cuff lead with a cuff around the vagus nerve can have wide ranging effects when stimulating the vagus nerve because the different fibers connect to many parts of the body.

As described further herein, a cuff lead can include a cuff body that wraps around a nerve and includes longitudinal electrodes distributed around the circumference of the cuff body. In at least some embodiments, these longitudinal electrodes permit the targeting of selected longitudinal regions along the circumference of the cuff body. In at least some embodiments, there are at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more longitudinal electrodes arranged in a set around the circumference of the cuff body and there may be one, two, three, or more sets of longitudinal electrodes that are spaced apart longitudinally from each other along the cuff body.

In at least some embodiments, the cuff may also include one or more radial electrodes that can be used as a counter-electrode to one or more selected longitudinal electrodes. In at least some embodiments, one or more of the longitudinal electrodes can be used as a cathode(s) and one or more of the radial electrodes can be used as an anode(s). Any other suitable selection of cathode(s) or anode(s) from the longitudinal or radial electrodes can be used.

In at least some embodiments, the longitudinal electrodes can be used to selectively stimulate a nerve fiber or a set of nerve fibers. For example, a cuff lead with a cuff around the vagus nerve may be used to selectively stimulate immunomodulation fibers without stimulating (or with reduced or subthreshold stimulation of) cardiovascular fibers or somatotopic fibers in the nerve. For example, the immunomodulation fibers may be used to enhance, decrease, or halt signaling to or from the brain. In at least some embodiments, a cuff lead with longitudinal electrodes can be used to selectively provide fiber or fascicular stimulation.

<FIG> illustrates one embodiment of a cuff <NUM> of a cuff lead <NUM> (<FIG>). The cuff <NUM> includes a cuff body <NUM> with longitudinal electrodes <NUM> disposed on an interior surface <NUM> of the cuff body and arranged around the circumference of the cuff body in two sets 356a, 356b. In the illustrated embodiment, each set 356a, 356b includes sixteen longitudinal electrodes <NUM>. Any other suitable number of electrodes can be used including, but not limited to, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more longitudinal electrodes. A cuff lead can have one, two, three, four, or more sets of longitudinal electrodes <NUM>. The number of longitudinal electrodes <NUM> in a set can be the same for each set or can differ. In the illustrated embodiment, the longitudinal electrodes <NUM> of each set are aligned longitudinally with electrodes of the other set. In other embodiments, the longitudinal electrodes <NUM> of each set can be staggered or unaligned with the electrodes of the other set.

In addition, the cuff <NUM> includes two radial electrodes 358a, 358b that wrap around at least <NUM>%, <NUM>%, <NUM>%, or <NUM>% of the circumference of the cuff body <NUM>. The cuff <NUM> also defines a slit <NUM> that extends the longitudinal length of the cuff body <NUM> so that the nerve can be loaded into the interior <NUM> of the cuff body by opening the slit to fit the cuff body over the nerve. The slit <NUM> is opened or initially sized to allow the target nerve (not shown) to be slipped, inserted, fed, or otherwise received into the cuff <NUM> such that the cuff <NUM> wraps around the target nerve. In at least some embodiments, the slit <NUM> allows the cuff <NUM> to be easily moved over and around the target nerve or relative to the target nerve whether rotationally or transitionally.

The electrodes <NUM>, 358a, 358b can be formed using any conductive, biocompatible material. Examples of suitable materials include metals, alloys, conductive polymers, conductive carbon, and the like, as well as combinations thereof. In at least some embodiments, one or more of the electrodes <NUM> are formed from one or more of: platinum, platinum alloys such as platinum iridium, palladium alloys such as palladium rhodium, titanium, titanium alloys, nickel alloys, cobalt alloys, nickel/cobalt alloys, stainless steel, tantalum, conductive carbon, conductive plastics, epoxy or other adhesive filled with metallic powder, Nitinol™, or the like or any combination thereof. The electrodes <NUM>, 358a, 358b can be formed by any suitable process including, but not limited to, machining, molding (for example, powdered metal molding), photolithography, additive techniques, stamping, or the like or any combination thereof.

In at least some embodiments, the electrodes <NUM>, 358a, 358b have a contact surface that is flush or slightly protruding (for example, no more than <NUM>, <NUM>, or <NUM> from the cuff body <NUM> which, at least in some circumstances, may reduce or eliminate physical pressure on the nerve. It will be recognized that the electrodes can be used to provide electrical stimulation or to sense electrical signals from tissue or any combination thereof.

In at least some embodiments, the longitudinal electrodes <NUM> have a width of no more than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> micrometers (µm) and a length of at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more millimeters (mm). The width of the longitudinal electrodes corresponds to a distance in the circumferential direction <NUM> around the cuff body. In at least some embodiments, the length of the longitudinal electrodes <NUM> is no more than <NUM>. The length of the longitudinal electrodes corresponds to a distance along the longitudinal direction <NUM> of the cuff body. In at least some embodiments, the longitudinal electrodes <NUM> have an aspect ratio (length/width) or at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more. In at least some embodiments, each of the electrodes <NUM> has the same width, length, and aspect ratio. In other embodiments, the electrodes <NUM> can have different widths, lengths, or aspect ratios with electrodes of a set have the same or different widths, lengths, or aspect ratios within the set or between sets.

In at least some embodiments, the longitudinal electrodes <NUM> are rectangular or rectangular with rounded corners. Any other suitable shape can be used for the longitudinal electrodes including, but not limited to, oblong, oval, modified rectangular with one or more sides (or portions of sides) that are curved, or the like or any combination thereof. The length and width measurements described in the preceding paragraph correspond to the longest or widest portion of the electrode <NUM>. For example, for an oval electrode, the length along the major axis of the oval corresponds to the length measurement and the length along the minor axis corresponds to the width measurement.

The narrow width of the longitudinal electrodes <NUM> can facilitate the ability to select particular fibers or groups of fibers in the nerve and steer the stimulation to the selected fiber or group of fibers. The number of longitudinal electrodes <NUM> in each set can further enhance the fiber selectivity with increasing numbers of longitudinal electrodes <NUM> providing more selectivity. Stimulation can be performed using one or more of the longitudinal electrodes <NUM>. The selection of an appropriate radial electrode 358a, 358b (or one or more of the longitudinal electrodes <NUM>) as the counter-electrode can further enhance steering of the stimulation to the selected fiber or group of fibers.

The cuff body <NUM> can be formed of any suitable biocompatible and biostable non-conductive material including, but not limited to, polymer materials such as silicone, polyurethane, polyetheretherketone ("PEEK"), epoxy, or the like or any combination thereof. In at least some embodiments, the cuff body <NUM> can have a circular, oval, or any other suitable cross-sectional shape and, at least in some embodiments, may be sufficiently flexible to alter the cross-sectional shape to accommodate the nerve. In at least some embodiments, the electrodes <NUM>, 358a, 358b can be molded with the cuff body <NUM> or formed by techniques such as etching or ablation of conductive layers, films, or the like. In at least some embodiments, the cuff body <NUM> has an inner diameter (which can correspond to the largest diameter of a non-circular cuff body) in a range of <NUM> to <NUM> or in a range of <NUM> to <NUM>. In at least some embodiments, the cuff body <NUM> has a length of at least <NUM>, <NUM>, or <NUM>.

In at least some embodiments, the cuff body <NUM> can be formed using any suitable technique including, but not limited to, molding, casting, formed in a sheet and then shaped using adhesive as a binder, formed flat and shaped using heat, formed flat and attached to a cuff-shaped scaffold, pressed or extruded into the cuff shape, or the like or any combination thereof. In at least some embodiments, the electrodes <NUM> can be attached to the cuff body <NUM> using any suitable technique including, but not limited to, attaching with adhesive, molding (for example, insert molding) into the cuff body, using heat to adhere the electrodes to the cuff body, heating and pressing the electrodes into the cuff body, depositing electrode material on the cuff body and using photolithography and etching, or the like or any combination thereof.

In at least some embodiments, the interior surface <NUM> of the cuff body <NUM> can be coated with a cushioning layer <NUM> (<FIG>) to act as a cushion to reduce damage to the nerve. Examples of materials for the cushioning layer <NUM> include, but are not limited to, paraffin, a combination of isotonic saline and artificial cerebrospinal fluid, or the like or any combination thereof. The cushioning layer <NUM> is made of a material that permits flow of current from the electrodes <NUM> to the nerve through the cushioning layer.

In at least some embodiments, once the cuff <NUM> has been placed in a desired position relative to the target nerve, the edges of the cuff body <NUM> defining the slit360 can be sutured to capture the target nerve without undesirably compressing the target nerve. In at least some embodiments, suture holes (not shown) are optionally incorporated into the edges of the cuff <NUM> to allow for closing or partially closing the cuff <NUM> around the target nerve.

<FIG> illustrates another embodiment of a cuff <NUM> with a cuff body <NUM> and longitudinal electrodes <NUM> arranged in four groups 356a, 356b, 356c, 356d with sixteen electrodes in each group. The cuff <NUM> includes three radial electrodes 358a, 358b, 358c.

<FIG> illustrates another embodiment of a cuff <NUM> with a cuff body <NUM> and longitudinal electrodes <NUM> arranged in four groups 356a, 356b, 356c, 356d with sixteen electrodes in each group. The cuff <NUM> includes six radial electrodes 358a, 358b, 358c, 358d, 358e, 358f that each extend around less than half the circumference of the cuff body <NUM> (for example, at least <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, or <NUM>% of the circumference of the cuff body) with two of these radial electrodes disposed in each of three sets. It will be understood that other arrangement can include, for example, three, four, six or more radial electrodes (or any other number of radial electrodes) per set. The radial electrodes of a set can extend a same amount around the circumference of the cuff body <NUM> or can extend by different amounts around the circumference of the cuff body. Each set can be identical, or the sets can have a different arrangement of radial electrodes. In at least some embodiments, the radial electrodes of a set, in combination, extend around at least <NUM>%, <NUM>%, <NUM>%, or <NUM>% of the circumference of the cuff body <NUM>.

<FIG> illustrates yet another embodiment of a cuff <NUM> with a cuff body <NUM> and longitudinal electrodes <NUM> arranged in four groups 356a, 356b, 356c, 356d with <NUM> electrodes in each group. The cuff <NUM> includes two radial electrodes 358a, 358b.

<FIG> illustrates a cross-section of the cuff <NUM> of <FIG> disposed around the vagus nerve <NUM> with the longitudinal electrodes <NUM> arranged around the circumference of the cuff and vagus nerve. Optionally, the cushioning layer <NUM> is disposed between the cuff <NUM>/electrodes <NUM> and the nerve <NUM>.

The cuff lead <NUM> (<FIG>) can be coupled to one or more control modules <NUM> (<FIG>). When the cuff lead <NUM> has many longitudinal electrodes <NUM>, multiple control modules <NUM> may be used to independently control the longitudinal electrodes <NUM>. Additionally or alternatively, multiplexing techniques and arrangements can be used to provide stimulation to selected longitudinal electrodes <NUM>. Multiplexing arrangements may be part of the control module <NUM>, cuff lead <NUM>, or a separate module or the like or any combination thereof. Examples of multiplexing and of independent control and delivery of stimulation through selected electrodes can be found in <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>; and <CIT> and <CIT>.

<FIG> is a schematic overview of one embodiment of components of an electrical stimulation arrangement <NUM> that includes an electrical stimulation system <NUM> with a lead <NUM>, stimulation circuitry <NUM>, a power source <NUM>, and an antenna <NUM>. The electrical stimulation system can be, for example, any of the electrical stimulation systems described above. It will be understood that the electrical stimulation arrangement can include more, fewer, or different components and can have a variety of different configurations including those configurations disclosed in the stimulator references cited herein.

If the power source <NUM> is a rechargeable battery or chargeable capacitor, the power source may be recharged/charged using the antenna <NUM>, if desired. Power can be provided for recharging/charging by inductively coupling the power source <NUM> through the antenna <NUM> to a recharging unit <NUM> external to the user. Examples of such arrangements can be found in the references identified above.

In at least some embodiments, electrical current is emitted by the electrodes (such as electrodes <NUM> in <FIG>) on the lead <NUM> to stimulate nerve fibers, muscle fibers, or other body tissues near the electrical stimulation system. The stimulation circuitry <NUM> can include, among other components, a processor <NUM> and a receiver <NUM>. The processor <NUM> is generally included to control the timing and electrical characteristics of the electrical stimulation system. For example, the processor <NUM> can, if desired, control one or more of the timing, frequency, strength, duration, and waveform of the pulses. In addition, the processor <NUM> can select which electrodes can be used to provide stimulation, if desired. In some embodiments, the processor <NUM> selects which electrode(s) are cathodes and which electrode(s) are anodes. In some embodiments, the processor <NUM> is used to identify which electrodes provide the most useful stimulation of the desired tissue.

Any processor can be used and can be as simple as an electronic device that, for example, produces pulses at a regular interval or the processor can be capable of receiving and interpreting instructions from an external programming unit <NUM> that, for example, allows modification of pulse characteristics. In the illustrated embodiment, the processor <NUM> is coupled to a receiver <NUM> which, in turn, is coupled to the antenna <NUM>. This allows the processor <NUM> to receive instructions from an external source to, for example, direct the pulse characteristics and the selection of electrodes, if desired.

In at least some embodiments, the antenna <NUM> is capable of receiving signals (e.g., RF signals) from an external telemetry unit <NUM> that is programmed by the programming unit <NUM>. The programming unit <NUM> can be external to, or part of, the telemetry unit <NUM>. The telemetry unit <NUM> can be a device that is worn on the skin of the user or can be carried by the user and can have a form similar to a pager, cellular phone, or remote control, if desired. As another alternative, the telemetry unit <NUM> may not be worn or carried by the user but may only be available at a home station or at a clinician's office. The programming unit <NUM> can be any unit that can provide information to the telemetry unit <NUM> for transmission to the electrical stimulation system <NUM>. The programming unit <NUM> can be part of the telemetry unit <NUM> or can provide signals or information to the telemetry unit <NUM> via a wireless or wired connection. One example of a suitable programming unit is a computer operated by the user or clinician to send signals to the telemetry unit <NUM>.

The signals sent to the processor <NUM> via the antenna <NUM> and the receiver <NUM> can be used to modify or otherwise direct the operation of the electrical stimulation system <NUM>. For example, the signals may be used to modify the pulses of the electrical stimulation system such as modifying one or more of pulse duration, pulse frequency, pulse waveform, and pulse strength. The signals may also direct the electrical stimulation system <NUM> to cease operation, to start operation, to start charging the battery, or to stop charging the battery.

Optionally, the electrical stimulation system <NUM> may include a transmitter (not shown) coupled to the processor <NUM> and the antenna <NUM> for transmitting signals back to the telemetry unit <NUM> or another unit capable of receiving the signals. For example, the electrical stimulation system <NUM> may transmit signals indicating whether the electrical stimulation system <NUM> is operating properly or not or indicating when the battery needs to be charged or the level of charge remaining in the battery. The processor <NUM> may also be capable of transmitting information about the pulse characteristics so that a user or clinician can determine or verify the characteristics.

Claim 1:
An electrical stimulation lead (<NUM>) comprising:
a cuff (<NUM>; <NUM>) comprising
a cuff body (<NUM>) having an exterior surface, an interior surface (<NUM>), and a circumference,
a plurality of longitudinal electrodes (<NUM>) disposed on the interior surface of the cuff body (<NUM>), wherein each of the longitudinal electrodes (<NUM>) has an aspect ratio of length/width of at least <NUM>, wherein the plurality of longitudinal electrodes (<NUM>) is divided into at least one set with each set comprising at least sixteen of the longitudinal electrodes spaced apart from each other in a circumferential arrangement round the circumference of the cuff body (<NUM>), and
a longitudinal slit (<NUM>) extending through the cuff body (<NUM>) and further extending along an entire length of the cuff body (<NUM>), the longitudinal slit (<NUM>) operable to receive a portion of a target nerve from a region outside of the cuff to within the cuff body (<NUM>);
a lead body (<NUM>) coupled to the cuff (<NUM>; <NUM>); and
a plurality of conductors (<NUM>) extending through the lead body (<NUM>) and the cuff (<NUM>; <NUM>) with the plurality of conductors (<NUM>) electrically coupled to the longitudinal electrodes (<NUM>).