Patent Publication Number: US-8977369-B1

Title: Sound processing assembly for use in a cochlear implant system

Description:
This application is a continuation of U.S. patent application Ser. No. 12/697,028, filed Jan. 29, 2010, now U.S. Pat. No. 8,352,046, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/148,648, filed Jan. 30, 2009, which application is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     The sense of hearing in human beings involves the use of hair cells in the cochlea that convert or transduce audio signals into auditory nerve impulses. Hearing loss, which may be due to many different causes, is generally of two types: conductive and sensorineural. Conductive hearing loss occurs when the normal mechanical pathways for sound to reach the hair cells in the cochlea are impeded. These sound pathways may be impeded, for example, by damage to the auditory ossicles. Conductive hearing loss may often be overcome through the use of conventional hearing aids that amplify sound so that audio signals can reach the hair cells within the cochlea. Some types of conductive hearing loss may also be treated by surgical procedures. 
     Sensorineural hearing loss, on the other hand, is caused by the absence or destruction of the hair cells in the cochlea which are needed to transduce audio signals into auditory nerve impulses. People who suffer from sensorineural hearing loss are unable to derive any benefit from conventional hearing aid systems. 
     To overcome sensorineural hearing loss, numerous cochlear implant systems—or cochlear prosthesis—have been developed. Cochlear implant systems bypass the hair cells in the cochlea by presenting electrical stimulation directly to the auditory nerve fibers. Direct stimulation of the auditory nerve fibers leads to the perception of sound in the brain and at least partial restoration of hearing function. 
     To facilitate direct stimulation of the auditory nerve fibers, an array of electrodes may be implanted in the cochlea. The electrodes form a number of stimulation channels through which electrical stimulation pulses may be applied directly to auditory nerves within the cochlea. An audio signal may then be presented to a patient by translating the audio signal into a number of electrical stimulation pulses and applying the stimulation pulses directly to auditory nerves within the cochlea via one or more of the electrodes. 
     Traditional cochlear implant systems include a behind-the-ear (“BTE”) sound processing unit configured to communicate with an implantable cochlear stimulator. The BTE sound processing unit includes both a processor and removable battery module, and may also include a removable microphone. Hence, the BTE unit can seem quite heavy to the patient after being worn all day. Many cochlear implant patients would like to be able to reduce the size and weight of what is worn on the ear, but do not want to sacrifice battery capacity by using a smaller battery module. 
     SUMMARY 
     In accordance with the invention(s) described and claimed herein, exemplary cochlear implant systems include a sound processing assembly configured to be external to a patient and first and second extension members coupled to the sound processing assembly. The sound processing assembly includes a sound processing unit configured to process an audio signal and transmit one or more control parameters based on the audio signal to an implantable cochlear stimulator (also referred to as a “cochlear implant”, or “CI”). The sound processing assembly also includes a battery module configured to be electrically coupled to the sound processing unit and provide operating power to the sound processing unit and the CI. The first extension member has a distal portion configured to be coupled to a first ear of the patient and the second extension member has a distal portion configured to be coupled to a second ear of the patient. 
     Additional or alternative cochlear implant systems include a bilateral sound processing assembly configured to be external to a patient and first and second extension members coupled to the bilateral sound processing assembly. The bilateral sound processing assembly includes a sound processing unit configured to process an audio signal and transmit one or more control parameters based on the audio signal to a first cochlear implant, or CI-1, corresponding to a first ear of the patient and to a second cochlear implant, or CI-2, corresponding to a second ear of the patient, and a battery module configured to be electrically coupled to the sound processing unit and provide operating power to the sound processing unit. The first extension member has a distal portion configured to be coupled to the first ear and the second extension member has a distal portion configured to be coupled to the second ear. 
     Additional or alternative cochlear implant systems include: (1) a first cochlear implant, or CI-1, configured to apply electrical stimulation representative of an audio signal to a stimulation site within a right cochlea of a patient in accordance with one or more control parameters; (2) a second cochlear implant, or CI-2, configured to apply electrical stimulation representative of the audio signal to a stimulation site within a left cochlea of the patient in accordance with one or more other control parameters; and (3) a bilateral sound processing assembly configured to be external to the patient. The bilateral sound processing assembly includes a sound processing unit configured to process the audio signal and transmit the control parameters to the CI-1 and/or the CI-2, as required. A battery module provides operating power to the sound processing unit, as well as to the CI-1 and the CI-2. The battery module may be detachably coupled to the sound processing unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate various embodiments of the principles described herein and are a part of the specification. The illustrated embodiments are merely examples and do not limit the scope of the disclosure. 
         FIG. 1  illustrates an exemplary cochlear implant (CI) system according to principles described herein. 
         FIG. 2  illustrates an exemplary behind the ear (BTE) unit according to principles described herein. 
         FIG. 3  illustrates an exemplary external sound processor portion that may be a part of a cochlear implant system according to principles described herein. 
         FIG. 4  illustrates another exemplary external sound processor portion that may be a part of a bilateral cochlear implant system according to principles described herein. 
         FIG. 5  shows an exemplary configuration wherein a sound processing assembly is worn behind the head of a patient according to principles described herein. 
         FIG. 6  illustrates another exemplary external sound processor portion that may be a part of a bilateral cochlear implant system according to principles described herein. 
         FIG. 7  shows an exemplary configuration wherein a sound processing assembly is attached to a belt of a patient according to principles described herein. 
         FIG. 8  illustrates an exemplary configuration wherein a sleeve at least partially surrounds the extension members and the sound processing assembly according to principles described herein. 
     
    
    
     Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. 
     DETAILED DESCRIPTION 
     Exemplary cochlear implant systems and methods are described herein. In some examples, the systems include a sound processing assembly configured to be external to a patient along with first and second extension members coupled to the sound processing assembly. The sound processing assembly includes a sound processing unit configured to process an audio signal and transmit one or more control parameters based on the audio signal to an implantable cochlear stimulator, or cochlear implant (“CI”), and a battery module configured to be electrically coupled to the sound processing unit and provide operating power to the sound processing unit. The battery module also will typically provide operating power to the CI. The first extension member has a distal portion configured to be coupled to a first ear of the patient and the second extension member has a distal portion configured to be coupled to a second ear of the patient. 
     The systems and methods described herein are advantageous in many instances because they reduce the size and weight of what a cochlear implant patient has to wear behind his or her ears. They also facilitate removable coupling of the battery module to the sound processing unit, which allows a patient to interchange the type of battery module that is used to provide power to the sound processing unit. Additional or alternative advantages of the present systems and methods are described in more detail below. 
     In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present systems and methods. It will be apparent, however, to one skilled in the art that the present systems and methods may be practiced without these specific details. Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearance of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment. 
     To facilitate an understanding of the methods and systems described herein, an exemplary cochlear implant system  100  will now be described in connection with  FIG. 1 . Exemplary cochlear implant systems suitable for use as described herein include, but are not limited to, those disclosed in U.S. Pat. Nos. 4,400,590; 4,532,930; 4,592,359; 4,947,844; 5,824,022; 6,219,580; 6,272,382; and 6,308,101. All of these listed patents are incorporated herein by reference in their respective entireties. 
     As shown in  FIG. 1 , the cochlear implant system  100 , also referred to herein as a cochlear prosthesis, includes an external sound processor portion  110  and an implanted cochlear stimulation portion  120 . The sound processor portion  110  may include a sound processing unit  130 , a microphone  140 , a headpiece  145 , and/or additional circuitry as best serves a particular application. The cochlear stimulation portion  120  (also referred to sometimes as a cochlear implant, or “CI”, portion) may include an implantable cochlear stimulator (ICS)  150 , a lead  160  with an array of electrodes  170  disposed thereon, and/or additional circuitry as best serves a particular application. It will be recognized that the sound processor portion  110  may alternatively be located internal to the patient. 
     The microphone  140  of  FIG. 1  is configured to sense audio signals and convert the sensed signals to corresponding electrical signals. In some examples, the audio signal may include speech. The audio signal may additionally include music, noise, and/or other sounds. The electrical signals are sent to the sound processing unit  130  over an electrical or other suitable link. Alternatively, the microphone  140  may be connected directly to, or integrated with, the sound processing unit  130 . 
     The sound processing unit  130  may include any combination of hardware, software, and/or firmware as best serves a particular application. For example, the sound processing unit  130  may include one or more processors, digital signal processors (DSPs), filters, programmable memory units, storage mediums, etc. 
     In some examples, the sound processing unit  130  may be configured to process the converted audio signals in accordance with a selected sound processing strategy to generate appropriate stimulation parameters for controlling the electrical stimulation generated by the implantable cochlear stimulator  150 . The stimulation parameters may control various parameters of the stimulation current applied to a stimulation site including, but not limited to, frequency, pulse width, amplitude, waveform (e.g., square or sinusoidal), electrode polarity (i.e., anode-cathode assignment), location (i.e., which electrode pair or electrode group receives the stimulation current), burst pattern (e.g., burst on time and burst off time), duty cycle or burst repeat interval, spectral tilt, ramp on time, and ramp off time of the stimulation current that is applied to the stimulation site. 
     The lead  160  of  FIG. 1  is adapted to be inserted within a duct of a patient&#39;s cochlea. As shown in  FIG. 1 , the lead  160  includes an array of electrodes  170  disposed along its length. It will be recognized that any number of electrodes  170  may be disposed along the lead  160  as may serve a particular application. 
     Each of the electrodes  170  is electrically coupled to the implantable cochlear stimulator  150 . Electronic circuitry within the implantable cochlear stimulator  150  may therefore be configured to apply stimulation current to selected pairs or groups of electrodes  170  in accordance with a specified stimulation pattern controlled by the sound processing unit  130 . 
     As mentioned, the implantable cochlear stimulator  150  and lead  160  may be implanted within the patient while the sound processing unit  130  and the microphone  140  are configured to be located outside the patient, e.g., behind the ear. Hence, the implantable cochlear stimulator  150  and the sound processing unit  130  may be transcutaneously coupled via a suitable data or communications link  180 . The communications link  180  allows power and control signals to be sent from the sound processing unit  130  to the implantable cochlear stimulator  150 . In some embodiments, data and status signals may also be sent from the implantable cochlear stimulator  150  to the sound processing unit  130 . 
     The external and implantable portions of the cochlear implant system  100  may each include one or more coils configured to transmit and receive power and/or control signals via the data link  180 . For example, the external portion  110  of the cochlear implant system  100  may include an external coil  190  disposed within headpiece  145 , which may be configured to be affixed to the patient&#39;s head. The implantable portion of the cochlear implant system  120  may include an implantable coil  195  configured to be inductively coupled to the external coil  190 , thereby allowing data and power signals to be wirelessly transmitted between the external portion and the implantable portion of the cochlear implant system  100 . Because in certain embodiments, the external portion  110  of the cochlear implant system  100  may not always be within close proximity to the implantable portion of the cochlear implant system  120 , such as when the external portion  110  is removed for sleeping, the system may be configured to recognize when the implantable coil  195  and the external coil  190  are within range of one another. 
     The sound processing unit  130  and the implantable cochlear stimulator  150  may be configured to operate in accordance with one or more control parameters. These control parameters may be configured to specify one or more stimulation parameters, operating parameters, and/or any other parameter as may serve a particular application. Exemplary control parameters include, but are not limited to, most comfortable current levels (“M levels”), threshold current levels, channel acoustic gain parameters, front and backend dynamic range parameters, current steering leakage parameters, pulse rate values, pulse width values, filter characteristics, and dynamic compression parameters. Many other control parameters may be specified as may serve a particular application. 
     In some examples, a patient may be fitted with two cochlear implant systems  100 —one for each ear. In such a bilateral configuration, a first implantable cochlear stimulator  150  is implanted within a first ear and a second implantable cochlear stimulator  150  is implanted within a second ear. First and second sound processing units  130  may be configured to control an operation of the first and second implantable cochlear stimulators  150 , respectively. 
     In some examples, the sound processing unit  130  may be embodied by or included within a BTE unit.  FIG. 2  illustrates an exemplary BTE unit  200 . As shown in  FIG. 2 , the BTE unit  200  may include sound processing unit  130 , a battery module  210 , and microphone  140  coupled one to another. In some examples, the BTE unit  200  may be removably coupled to headpiece  145  via a cable  220 . 
     Battery module  210  may be configured to provide operating power for one or more components of the BTE unit  200 . In some examples, the battery module  210  may be selectively removed from the sound processing unit  130 . In this manner, differently sized battery units  210  may be coupled to the sound processing unit  130  in order to provide a desired amount of operating power to the components of the BTE unit  200 . In general, as the size of the battery module  210  increases, the longer the BTE unit  200  may operate before having to recharge or replace the battery module  210 . 
     As shown in  FIG. 2 , the BTE unit  200  may be dimensioned such that it may be worn behind the ear. However, as mentioned, the BTE unit  200  may seem quite heavy to a patient after being worn all day, especially when a relatively large battery module  210  is attached to the sound processing unit  130 . Moreover, the positioning of the BTE unit  200  behind the ear may impede the ability of the patient to participate in sports, exercise, and/or other physical activities that may cause the BTE unit  200  to become dislodged or otherwise damaged. In addition, BTE units  200  are readily noticeable and are often a source of embarrassment to cochlear implant patients, especially children. These drawbacks of BTE units  200  are exasperated for bilateral cochlear implant patients. 
     To this end, the systems and methods described herein provide configurations wherein one or more components of a cochlear implant system  100  may be worn behind the head or at some other convenient location. These configurations, as will be described in more detail below, minimize many of the inconveniences and drawbacks of traditional cochlear implant systems. 
       FIG. 3  illustrates an exemplary external sound processor portion  300  that may be a part of a cochlear implant system  100 . As shown in  FIG. 3 , a sound processing assembly  310  may be coupled to first and second extension members  320 - 1  and  320 - 2 , collectively referred to herein as “extension members  320 ”. The sound processing assembly  310  may include a battery module  210  removably coupled to a sound processing unit  130  which has a length that is substantially greater than its height and width. To this end, the battery module  210  may include a connector assembly (not shown) configured to be removably coupled to a corresponding connector assembly (not shown) that is a part of the sound processing unit  130 . 
     Because the battery module  210  is removably coupled to the sound processing unit  130 , the battery module  210  may be easily interchanged with other battery modules  210  as may serve a particular application. 
     The external sound processor portion  300  shown in  FIG. 3  may be configured to be used by a bilateral cochlear implant patient. To this end, the sound processing unit  130  may include a bilateral sound processing unit  130  that is configured to control the operation of implantable cochlear stimulators  150  (see  FIG. 1 ), there being one cochlear stimulator implanted in each ear of a patient, or a total of two cochlear stimulators  150 . In some examples, a single sound processing unit  130  configured to control both implantable cochlear stimulators  150  eliminates redundant circuits and/or components that may be present in separate sound processing units  130 . However, in some alternative examples, as will be described in more detail below, the sound processing assembly  300  may include first and second sound processing units  130  each configured to control a corresponding implantable cochlear stimulator  150 . 
     As shown in  FIG. 3 , the sound processing assembly  310  may be generally elongate so as to be able to fit behind a head of the patient. In some examples, the sound processing assembly  310  may be contoured or otherwise fitted to the head of a particular patient to optimize fitting, comfort, and/or aesthetic appeal. In some examples, the sound processing assembly  310  may be at least partially surrounded by a housing or encasing made out of any suitable material. 
     Extension members  320  may be coupled at a proximal end to the sound processing assembly  310  and configured to extend in a generally perpendicular direction from the sound processing assembly  310 , similar to eyeglasses arm members. As shown in  FIG. 3 , the distal portions of the extension members  320  may be generally curved so that they may be worn behind the ears of a patient. It will be recognized that the distal portion of the extension members  320  may alternatively have any other shape as may serve a particular application. For example, the distal portion of the extension members  320  may be generally straight or of any other suitable shape or dimension. In some examples, one or more of the extension members  320  may be configured to house one or more conductive wires or other components of the external sound processor portion  300 . 
     In some examples, a microphone  140  may be coupled to a distal end of each extension member  320  such that the microphone  140  is positioned adjacent to or near the opening of the ear. For example, microphone  140 - 1  is coupled to the distal end of extension member  320 - 1  and microphone  140 - 2  is coupled to the distal end of extension member  320 - 2 . The microphones  140  may alternatively be coupled to any other component of the external sound processor portion  300  as may serve a particular application. 
     The sound processing unit  130  may be electrically coupled to one or more headpieces (e.g., headpieces  145 - 1  and  145 - 2 , collectively referred to herein as “headpieces  145 ”) via one or more corresponding cables (e.g., cables  330 - 1  and  330 - 2 , collectively referred to herein as “cables  330 ”). The cables  330  may be made out of any suitable material. In some examples, the cables  330  may be physically coupled to the extension members  320 , as shown in  FIG. 3 . In this example, one or more conductive wires configured to facilitate electrical coupling of the headpieces  145  to the sound processing unit  130  may be disposed within cable  330  and/or within the extension members  330 . In some alternative examples, the cables  330  may be coupled directly to the sound processing unit  130 , as described below in connection with  FIG. 4 . In yet other alternative examples, the headpieces  145  may be wirelessly coupled to the sound processing unit  130 . 
       FIG. 4  illustrates another exemplary external sound processor portion  400  that may be a part of a bilateral cochlear implant system  100 . As shown in  FIG. 4 , the sound processing assembly  310  may include first and second sound processing units  130 - 1  and  130 - 2 , referred to herein as “sound processing units  130 ”. Each sound processing unit  130  is configured to control a corresponding implantable cochlear stimulator  150 . For example, sound processing unit  130 - 1  may be configured to control an implantable cochlear stimulator  150  having its lead  160 , and associated electrodes  170  (see  FIG. 1 ), placed within the cochlea of the left ear. Similarly, sound processing unit  130 - 2  may be configured to control an implantable cochlear stimulator  150  having its lead  160 , and associated electrodes  170 , placed within the cochlear the right ear. 
     In some examples, the battery module  210  may be removably coupled to one or both of the sound processing units  130 . To this end, the battery module  210  may include connector assemblies disposed at both ends thereof, wherein each of the connector assemblies are configured to be coupled to corresponding connector assemblies that are part of the sound processing units  130 . 
     As shown in  FIG. 4 , the cables  330 - 1  and  330 - 2 , configured to couple the headpieces  145  to their respective sound processing units  130 , may be coupled directly to the sound processing units  130 . To this end, the sound processing units  130  may each include a connector assembly (e.g., connector assembly  400 - 1  and connector assembly  400 - 2 ) configured to facilitate coupling of the cables  330  to their respective sound processing units  130 . 
     As mentioned, the sound processing assembly  310  may be configured to be worn behind the head of a patient. To illustrate,  FIG. 5  shows an exemplary configuration wherein the sound processing assembly  310  is worn behind the head  500  of a patient. As shown in  FIG. 5 , the extension members  320  are worn behind the ears such that the elongate sound processing assembly  310  is positioned horizontally behind the head  500 . By positioning the sound processing assembly  310  behind the head  500 , the size and weight of what is worn behind the ears is reduced. 
     The sound processing assembly  310  may be alternatively worn by a patient at any other suitable location. For example,  FIG. 6  illustrates another exemplary external sound processor portion  600  that may be a part of a bilateral cochlear implant system  100  wherein the sound processing assembly  310  is configured to be worn by a patient at any suitable location. As shown in  FIG. 6 , cables  610 - 1  and  610 - 2 , collectively referred to herein as “cables  610 ”, may be coupled to the sound processing assembly  310 . Each cable is coupled to an earpiece (e.g., earpiece  620 - 1  and earpiece  620 - 2 , collectively referred to herein as “earpieces  620 ”). The earpieces  620  are configured to be worn behind the ears of the patient. Each earpiece  620  is coupled to a corresponding microphone  140  and to a corresponding headpiece  145 . It will be recognized that the microphones  140  and headpieces  145  may alternatively be coupled to the sound processing assembly  310  in any other way as may serve a particular application. 
     The cables  610  may be of any suitable length and may be flexible so as to allow the sound processing assembly  310  to be worn by the patient at any suitable location. To this end, the sound processing assembly  310  may include a clip assembly or other affixation assembly configured to allow the patient to clip or otherwise attach the sound processing assembly  310  to a belt, piece of clothing, or other object. 
     To illustrate,  FIG. 7  shows an exemplary configuration wherein the sound processing assembly  310  is attached to a belt  700  of a patient. The sound processing assembly  310  may be attached to the belt  700  in any suitable manner. For example, the sound processing assembly  310  may include a clip assembly configured to clip to the belt. It will be recognized that the sound processing assembly  310  may be attached to any other piece of clothing or to any body part as may serve a particular application. 
     As shown in  FIG. 7 , the cables  610  are joined together near the sound processing assembly  310  and are then routed to the ears of the patient, where they are separated again. In this manner, entanglement of the cables  610  may be minimized. As shown in  FIG. 7 , the cables  610  are long enough to allow the sound processing assembly  310  to be attached to belt  700  when the earpieces  620  are worn behind the ear. The configuration of  FIG. 7  is advantageous in many situations wherein the patient desires to hide the sound processing assembly  310  from view and/or avoid excessive weight on the ears. 
     In some instances, a cochlear implant patient may desire to participate in sports, exercise, and/or other physical activities. To this end, one or more components of the external sound processor portion  300  may be placed within a protective “sleeve.” The sleeve may be made out of any suitable material (e.g., neoprene, rubber, etc.). The sleeve is configured to protect one or more components of the external sound processor portion  300  from one or more environmental factors that the patient may encounter, such as rain, snow, dust, water, etc. The sleeve also may be used to prevent one or more components of the external sound processor portion  300  from becoming dislodged from the patient while the patient is engaged in sporting or other activities that may require sudden movements of the head. 
       FIG. 8  illustrates an exemplary configuration  800  wherein a sleeve  810  at least partially surrounds the extension members  320  and the sound processing assembly  310 . As shown in  FIG. 8 , distal ends  820 - 1  and  820 - 2 , collectively referred to herein as “distal ends  820 ”, of the sleeve  810  may be configured to fit over or otherwise couple to corresponding arm members  830 - 1  and  830 - 2  of eyeglasses  840 . In this manner, a patient with eyeglasses  840  may utilize the sleeve  810  to securely fasten the sound processing assembly  310  to the eyeglasses  840 . 
     In some examples, the sleeve  810  may include a slit extending at least partially along its length. The slit may allow the patient to remove the sound processing assembly  310  and extension members  320  from the sleeve  810 . 
     The preceding description has been presented only to illustrate and describe embodiments of the invention. It is not intended to be exhaustive or to limit the invention to any precise form disclosed. Many modifications and variations are possible in light of the above teaching.