Patent Description:
Subjective tonal tinnitus (i.e., ringing in the ear) is the phantom perception of sound when no external generating stimulus is present. Tinnitus may be unilateral, bilateral or non-localizing, and may present intermittently or continuously.

Subjective tonal tinnitus affects approximately a fourth of the US population and is a major source of disability affecting many domains of life. For some, tinnitus is merely a fleeting annoyance; however for many individuals, tinnitus may cause audiological, neurological or cognitive impairment resulting in poor attention, increased distractibility, anxiety, depression, and even suicide. Tinnitus remains the number one disability experienced by U. In <NUM> alone, more than <NUM> percent of all veteran disability claims were due to tinnitus, making it a top research priority of the U. Department of Defense and the Veterans Health Administration.

Despite substantial clinical research in humans and study of animal models, the exact mechanism(s) behind tinnitus remain largely unknown. It is currently held that tinnitus likely reflects inadequate reorganization within the central nervous system following a peripheral auditory system injury. The theory of cochlear deafferentation as a cause for tinnitus parallels phantom limb pain, where cortical maladaptation develops in response to loss of sensory input.

<CIT> Al describes an electrode lead with an integrated attachment mechanism for use with a cochlear implant system.

<CIT> Al describes an electrode apparatus for neurostimulation implants.

<CIT> describes systems for stimulation of the cochlea that mimic or replace the spontaneous background neural activity of the cochlea.

Currently, there are no FDA approved pharmacological therapies or surgical devices available for the treatment of tinnitus. Current treatment methods largely focus on counseling, cognitive behavioral therapy, masking, and sound therapy. Such strategies may help render tinnitus more tolerable, but such strategies do not abolish the symptom or reverse the underlying pathophysiological process.

The present invention is defined by independent claim <NUM>.

This document provides devices for treating tinnitus. For example, this document provides implantable electrodes and stimulation devices for delivering electrical stimulation to the cochlea region, such as on the surface of the cochlear bone including the promontory, or endosteally and/or intraosseously within the cochlear bone, to treat tinnitus.

In one aspect an electrode device for delivering electrical pulse stimuli to a patient's cochlear region includes: a lead including a single elongate insulated electrical conductor; a single electrode disposed at a distal end of the lead and in electrical communication with the insulated electrical conductor, where the electrode is configured to be intraosseously placed within a hole created in target tissue to deliver the electrical pulse stimuli to the patient's cochlear region; and an anchor element disposed adjacent to the electrode, where:.

In some embodiments, the electrode device further includes an implantable stimulator device in electrical communication with the lead and configured to generate the electrical pulse stimuli.

In some embodiments, the implantable stimulator device includes a magnet for aligning with an external device.

In some embodiments, the implantable stimulator device includes a receiver coil configured to wirelessly communicate through the patient's scalp with an external device.

In some embodiments, the electrode is an electrode screw that has a length selected to be suitable for the patient.

In some embodiments, the electrode is an electrode lug that has a length that is selected to be suitable for the patient.

In some embodiments, the electrode is an electrode lug that is configured to be fixed in the hole using an adhesive.

The subject matter described in this document can be implemented to realize one or more of the following advantages. Cochlear surface electrode(s), intraosseous electrode(s), endosteal electrode(s), subendosteal electrode(s) or short intracochlear electrode(s) (or a combination thereof), connected to a receiver/stimulator electronics package, can provide an effectual long-term treatment of tinnitus in many patients. Some embodiments described herein include a grid array, linear array, paired array or single stimulation electrode(s). A multi-electrode array can advantageously provide broad spatial coverage of the cochlear region. Additionally, various electrode pairs or groupings within the multi-electrode array can be activated (while others are deactivated) to provide a customized stimulation treatment that is effective for a particular patient's needs. In some embodiments, one or more electrodes can be placed intraosseously (e.g., in the cochlear bone). Such intraosseous placement can provide the advantage of delivering electrical stimulation in closer proximity to the cochlea (as compared to promontory surface placement). Other devices provided herein can advantageously deliver electrical stimulation to the vestibulocochlear nerve to treat tinnitus.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although methods and materials similar or equivalent to those described herein can be used to practice the invention, suitable methods and materials are described herein. In case of conflict between the present specification and a reference mentioned herein, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description herein.

Like reference numbers represent corresponding parts throughout.

This document provides devices for treating tinnitus and methods of using the devices to treat tinnitus. For example, this document provides implantable electrodes and stimulation devices for delivering electrical stimulation to the cochlear region to treat tinnitus. Cochlear surface electrode(s), endosteal electrode(s), subendosteal electrode(s), intraosseous electrode(s), or short intracochlear electrode(s) (or a combination thereof), connected to existing but modified cochlear implant receiver/stimulator technology, can provide a successful model for long-term treatment of tinnitus in a large number of patients. In some cases, patients can simply turn on the tinnitus implant when experiencing troublesome tinnitus and gain instant relief. With increasing use, it is likely many patients will enjoy lasting tinnitus suppression, hours and even days after the device is turned off (i.e., residual inhibition).

Using surface, endosteal, subendosteal, intraosseous, or short intracochlear electrodes (or a combination thereof), customized monopolar or bipolar stimulation can be performed to target specific patterns and frequencies of tinnitus. A surface grid of electrodes has the advantage of improved cochlear coverage. Endosteal and/or intraosseous electrodes in the promontory can place the electrical stimulation in closer proximity to the modiolus (the conical central axis of the cochlea) without risking sensorineural hearing loss. A short intracochlear electrode offers a direct method of cochlear stimulation. Devices and methods for each of the aforementioned treatment modalities are described further herein.

Referring to <FIG>, an implantable receiver/stimulator device <NUM> can be used in conjunction with the various types of electrode devices provided herein. Receiver/stimulator device <NUM> can be functionally akin to an implantable receiver/stimulator device used for cochlear implant electrical stimulation. Accordingly, receiver/stimulator device <NUM> is implanted under the post-auricular scalp and the lead wire(s) can travel through the mastoid and facial recess to the target electrode location(s). In some cases, for treating tinnitus, the target electrode location may be the bony cochlea, otic capsule, and/or promontory (e.g., endosteally and/or intraosseously). In some cases, for treating balance disorders, the target electrode location may be the bony labyrinth (e.g., surface, intraosseous, or intra-labyrinthine) including the semicircular canals and vestibule. For example, surface, intraosseous, and intra-labyrinthine electrodes can be placed in the region of the semicircular canals and vestibule to stimulate labyrinthine function. Electrical stimulation of this organ may be used to rehabilitate vestibular hypofunction or treat ongoing or recurrent vestibular diseases, such as Meniere's disease.

An external device (not shown) can be used to wirelessly communicate (through the patient's scalp) with the implanted receiver/stimulator device <NUM>. Such an external device can function to activate, program, power, control, and/or otherwise interact with receiver/stimulator device <NUM>. In some cases, receiver/stimulator device <NUM> can be programmed according to pulse width, current amplitude, stimulus rate, stimulation mode, and the like.

In the depicted receiver/stimulator device <NUM>, the receiver/stimulator device <NUM> includes a magnet <NUM>, a receiver coil <NUM>, a stimulator <NUM>, a ground lead <NUM>, a lead wire <NUM>, and one or more electrodes <NUM>. Magnet <NUM> can be used to magnetically couple and align receiver/stimulator device <NUM> with an external device. Receiver coil <NUM> is used to wirelessly communicate with an external device. Stimulator <NUM> controls the operations of receiver/stimulator device <NUM> and is the source of electrical stimuli. Lead wire <NUM> conducts the electrical stimuli to electrode <NUM>.

Electrode <NUM> delivers the electrical stimuli to tissue of the patient. It should be understood that electrode <NUM> is representative of any of the embodiments of electrodes described herein. That is, any electrode embodiment described herein can be used for electrode <NUM>. Ground lead <NUM> provides a path for the electrical stimuli to flow after the stimuli has been passed from electrode <NUM> to the tissue. It should be understood that the depicted receiver/stimulator device <NUM> provides just one nonlimiting example of the types of implantable receiver/stimulator devices that can be used in conjunction with the various types of electrode devices provided herein.

In some cases, prior to permanent electrode <NUM> placement, test electrodes can be placed on the patient's cochlea region via a transcanal tympanotomy using local anesthetic with the patient awake. An instrument set can be used to apply varying patterns of electrical stimulation, and the patient can convey which pattern resulted in greatest tinnitus reduction. Individual instruments will vary based on the number of electrodes and the distance between electrodes. Additionally, "pitch-masking" (also referred to as frequency matching) and CT imaging may assist in determining optimal electrode <NUM> positioning.

Referring to <FIG>, an example cochlear surface electrode device <NUM> can be used to deliver electrical pulses in a patient's cochlear region to treat tinnitus. Electrode device <NUM> includes a lead <NUM>, an electrode <NUM>, and an anchor element <NUM>. Lead <NUM> is an insulated conductor that puts electrode <NUM> in electrical communication with a source of electrical pulse stimuli (e.g., receiver/stimulator device <NUM>). Electrode <NUM> is an uninsulated conductive element that, when placed in contact with tissue, can deliver electrical stimuli to the tissue. Surface electrode device <NUM> is an example of a monopolar electrode device that can be used to treat tinnitus. Anchor element <NUM> is attached to lead <NUM> and/or electrode <NUM>.

In some cases, cochlear surface electrode device <NUM> is implanted such that electrode <NUM> is in contact with the patient's cochlear bone (e.g., promontory). Anchor element <NUM> can be used to couple electrode device <NUM> to the patient's tissue at the target site, and to provide migration resistance. In some cases, an adhesive (e.g., bone cement and the like) can be used to tack anchor element <NUM> to tissue (e.g., bone, cartilage, or soft tissue). In some cases, a mechanical anchor such as a screw or barbed member can be used to couple anchor element <NUM> to tissue. In the depicted example cochlear surface electrode device <NUM>, anchor element <NUM> defines a fenestration that can receive adhesive and/or a mechanical anchor.

Referring to <FIG>, another example cochlear surface electrode device <NUM> can be used to deliver electrical pulses in a patient's cochlear region to treat tinnitus. Electrode device <NUM> includes a lead <NUM>, an electrode pair <NUM>, and an anchor element <NUM>. In some examples, surface electrode device <NUM> is an example of a bipolar electrode device that can be used to treat tinnitus. That is, electrode pair <NUM> includes two electrodes. In some cases, one of the two electrodes functions as a cathode and the other functions as an anode. Hence, in some cases electrode pair <NUM>, when placed in contact with tissue, can deliver electrical stimuli to the tissue without the need for a separate ground lead (e.g., ground lead <NUM> as described above in reference to <FIG>). In some cases, both electrodes of electrode pair <NUM> are used as a cathode and a separate ground lead is used.

Similar to anchor element <NUM> described above, anchor element <NUM> defines a fenestration or other type of attachment feature that can receive adhesive and/or a mechanical anchor.

Referring to <FIG>, another example cochlear surface electrode device <NUM> can be used to deliver electrical pulses in a patient's cochlear region to treat tinnitus. Electrode device <NUM> includes a lead <NUM>, an electrode array <NUM>, and an anchor element <NUM>. Electrode array <NUM> can include any number of electrodes arranged in any configuration. Electrode array <NUM> can comprise a compliant material that can conform to the topography of the patient's tissue (including bone tissue such as the promontory). In some cases, a heat source (e.g., warm water) can be applied to electrode array <NUM> at the time of placement to increase the compliance of electrode array <NUM>.

Surface electrode device <NUM> is an example of a grid electrode device that can be used to treat tinnitus. That is, grid electrode array <NUM> includes two or more electrode pairs. In some cases, one electrode of each of the electrode pair(s) functions as a cathode and the other functions as an anode.

In some cases, individual electrode pairs of the two or more electrode pairs of electrode array <NUM> can be activated individually. That is, while some electrode pairs are utilized to deliver electrical stimuli, other electrode pairs can be selectively deactivated. In that manner, particular areas or zones of the patient's target tissue (e.g., cochlear region) can receive pulse stimuli, while other areas or zones do not. This functionality can be used to customize the treatment to best suit a particular patient. For example, various electrode pairs (or combinations of electrode pairs) can be experimentally activated to determine which electrode pairs provide the patient with the most relief from tinnitus symptoms.

Referring to <FIG>, in some cases one or more electrodes can be placed endosteally and/or intraosseously to treat tinnitus. For example, in some cases one or more electrodes of the present disclosure can be placed intraosseously in the bone tissue of the otic capsule (e.g., without penetrating through the endostium of the cochlea or cochlear lumen). Endosteal and/or intraosseous electrodes can place the electrical stimulation in close proximity to the modiolus (the conical central axis of the cochlea) without risking sensorineural hearing loss. The devices depicted in <FIG> can be used for such an implementation.

<FIG> depicts a drill device <NUM> that can be used with a rotary driver instrument. Drill device <NUM> includes a shank <NUM>, a depth limiter <NUM>, and a working portion <NUM>. Working portion <NUM> includes cutting edges that can remove tissue such as bone tissue to create a hole (e.g., such as a blind hole or through hole) in the target tissue layer (e.g., anywhere on the promontory including near or at the oval window, near or at the round window, etc.). The maximum depth of the hole can be controlled by depth limiter <NUM> (e.g., a flange portion). Depth limiter <NUM> can advantageously prevent the hole created from being a through-hole (i.e., from penetrating completely through the opposite side of the tissue layer, or into the cochlear lumen).

Patient populations naturally have differing anatomical features (such as promontory thicknesses and the like). Accordingly, a variety of differently sized drill devices <NUM> can be available so as to suit an individual patient's anatomy. For example, a set of drill devices <NUM> with depth limiter <NUM> at differing positions can be provided so that a particular drill device <NUM> can be used for a particular patient to make a hole of the proper depth for the particular patient's anatomy.

In most cases, the most suitable drill device <NUM> and/or electrode device for a particular patient can be determined in advance of the implant procedure. For example, in some cases a patient can undergo a pre-operative imaging procedure, such as a computerized tomography (CT) scan, to determine the patient's anatomical features such as, but not limited to, promontory thickness. Based on the inventor's investigations, minimal promontory thickness is about <NUM>-<NUM> and maximal promontory thickness is about <NUM>-<NUM>. Thus, a desirable hole depth (and intraosseous electrode length) can be about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, and/or anywhere within such ranges. In some cases, a set of multiple drill devices <NUM> will be made available in <NUM> depth increments, or <NUM> depth increments.

Referring to <FIG>, when a hole (e.g., a blind hole that does not completely break through the bone) has been created using drill device <NUM>, electrode device <NUM> can be attached to the target tissue using the hole. Electrode device <NUM> includes a lead <NUM>, an electrode screw <NUM>, and an anchor element <NUM>. To install electrode device <NUM>, electrode screw <NUM> is passed through a fenestration in anchor element <NUM> and into the hole created using drill device <NUM>.

Electrode screw <NUM> can serve multiple purposes. First, electrode screw <NUM> can anchor electrode device <NUM> endosteally and/or intraosseously to the target tissue (e.g., bony cochlea or labyrinth). Secondly, electrode screw <NUM> can include an electrode core that can deliver electrical pulse stimuli to the tissue with which it makes contact. A set of electrode screws <NUM> having differing lengths can be available so that a particular electrode screw <NUM> having a suitable length can be selected for a particular patient. Hence, in some cases, electrode device <NUM> can deliver electrical stimuli endosteally and/or intraosseously (e.g., to the promontory) to treat tinnitus. In some cases, an adhesive such as bone cement can be used in conjunction with electrode screw <NUM>.

Referring to <FIG>, when a hole has been created using drill device <NUM>, electrode device <NUM> can be attached to the target tissue within the hole. Electrode device <NUM> includes a lead <NUM> and an electrode lug <NUM>. To install electrode device <NUM>, electrode lug <NUM> is placed into the hole created using drill device <NUM>. In some cases, an adhesive (e.g., bone cement) can be used to fixate electrode lug <NUM> in the blind hole. Electrode lug <NUM> can include an electrode core that can deliver electrical pulse stimuli to the tissue with which it makes contact. A set of electrode devices <NUM> having differing lengths of electrode lugs <NUM> can be available so that a particular electrode device <NUM> having a suitable length of electrode lug <NUM> can be selected for a particular patient. Hence, in some cases, electrode device <NUM> can deliver electrical stimuli endosteally and/or intraosseously to a cochlear bone (e.g., to the promontory) to treat tinnitus.

Referring to <FIG>, another example electrode device <NUM> can be used to deliver electrical pulses in a patient's cochlear region to treat tinnitus. Electrode device <NUM> includes a lead <NUM>, one or more electrodes <NUM>, and an anchor element <NUM>.

Electrode device <NUM> is configured for delivering electrical stimuli shallowly within the patient's cochlea lumen. That is, in some cases a distal end portion <NUM> of electrode device <NUM> can be inserted within the patient's cochlea (e.g., through the round window or oval window). In such a case, anchor element <NUM> can act as a soft, flexible barb member to retain distal end portion <NUM> shallowly within the patient's cochlea. In that arrangement, electrode(s) <NUM> can thereafter deliver electrical pulses to the patient's cochlea to treat tinnitus.

Referring to <FIG>, in some cases devices having one or more electrodes can deliver electrical stimulation to the vestibulocochlear nerve to treat tinnitus. The devices depicted in <FIG> can be used for such an implementation.

Referring to <FIG>, another example electrode device <NUM> can be used to deliver electrical pulses in a patient's vestibulocochlear nerve region (e.g., vestibulocochlear nerve or cochlear nerve or vestibular nerve) to treat tinnitus. Electrode device <NUM> includes a lead <NUM> and an electrode array <NUM> disposed on a flexible band <NUM>. Electrode array <NUM> can include any number of electrodes arranged in any configuration. Electrode array <NUM> can be monopolar or bipolar.

Flexible band <NUM> can comprise a compliant material that can be wrapped around the patient's vestibulocochlear nerve. In some cases, a heat source (e.g., warm water) can be applied to flexible band <NUM> at the time of placement to increase the compliance of flexible band <NUM>. In some cases, flexible band <NUM> is malleable so that it retains its shape after being wrapped around the patient's vestibulocochlear nerve. Thereafter, electrical pulse stimuli can be delivered to the patient's vestibulocochlear nerve via electrode array <NUM>.

Referring to <FIG>, another example electrode device <NUM> can be used to deliver electrical pulses in a patient's vestibulocochlear nerve region to treat tinnitus. Electrode device <NUM> includes a lead <NUM> and an electrode hook <NUM>. Electrode hook <NUM> can include one or more than one electrodes arranged in any configuration. Electrode hook <NUM> can be monopolar or bipolar.

In some cases, electrode hook <NUM> can comprise a shape-memory material that tends to seek a curved or spiral shape such that electrode hook <NUM> will be wrapped around the patient's vestibulocochlear nerve. In some cases, a heat source (e.g., electrical current, a laser, and the like) can be applied to electrode hook <NUM> at the time of placement to activate the shape-memory property of electrode hook <NUM>. Thereafter, electrode hook <NUM> will tent to retain its shape after being wrapped around the patient's vestibulocochlear nerve. Electrical pulse stimuli can then be delivered to the patient's vestibulocochlear nerve via electrode hook <NUM>.

Referring to <FIG>, in some cases devices having one or more electrodes can deliver electrical stimulation within the vestibulocochlear nerve to treat tinnitus. The devices depicted in <FIG> can be used for such an implementation. That is, distal end portions of the electrode devices can penetrate and remain within the patient's vestibulocochlear nerve to treat tinnitus.

Referring to <FIG>, another example electrode device <NUM> can be used to deliver electrical pulses in a patient's vestibulocochlear nerve region to treat tinnitus. Electrode device <NUM> includes a lead <NUM>, an electrode needle <NUM>, and an anchor element <NUM>. Electrode needle <NUM> can include one or more than one electrodes arranged in any configuration. Electrode needle <NUM> can be monopolar or bipolar.

Electrode device <NUM> includes a distal end portion <NUM>. Distal end portion <NUM> can be inserted within the patient's vestibulocochlear nerve while electrode device <NUM> is configured as shown in <FIG>. Thereafter, anchor element <NUM> can be pivoted to the configuration shown in <FIG>. In that configuration, anchor element <NUM> acts as an anchor to provide migration resistance. Electrical pulse stimuli can then be delivered to within the patient's vestibulocochlear nerve via electrode needle <NUM>.

Referring to <FIG>, another example electrode device <NUM> can be used to deliver electrical pulses in a patient's vestibulocochlear nerve region to treat tinnitus. Electrode device <NUM> includes a lead <NUM> and an electrode needle <NUM>. Electrode needle <NUM> can include one or more than one electrodes arranged in any configuration. Electrode needle <NUM> can be monopolar or bipolar.

Claim 1:
An electrode device (<NUM>, <NUM>) for delivering electrical pulse stimuli to a patient's cochlear region, the electrode device comprising:
a lead (<NUM>, <NUM>) comprising a single elongate insulated electrical conductor;
a single electrode disposed at a distal end of the lead (<NUM>, <NUM>) and in electrical communication with the insulated electrical conductor, wherein the electrode is configured to be intraosseously placed within a hole created in target tissue to deliver the electrical pulse stimuli to the patient's cochlear region; and
an anchor element (<NUM>) disposed adjacent to the electrode,
characterised in that
the electrode is an electrode screw (<NUM>) including an electrode core, the anchor element (<NUM>) including a fenestration,
wherein the electrode screw (<NUM>) is configured to be passed through the fenestration in the anchor element into the hole created in the target tissue and to anchor the electrode device (<NUM>) intraosseously to the target tissue, and
wherein the electrode core is configured to deliver the electrical pulse stimuli intraosseously to the target tissue with which it makes contact.