Patent Abstract:
A system for allowing bilateral cochlear implant systems to be networked together. An adapter module that forms part of the system allows two standalone BTE units to be synchronized both temporally and tonotopically in order to maximize a patients listening experience. The system further allows a peer-to-peer network and protocol that includes two BTE units during normal operation, or two BTE units plus a host controller (PC, PDA, etc. . . . ) during fitting. The bilateral cochlear network includes four main components: (a) a communications interposer adapted to be inserted between the BTE battery and the BTE housing or modified BTE devices; (b) a communication channel over which communication takes place between the connected devices, including the protocol governing access to such channel; (c) the synchronization mechanisms used to achieve synchronization between the connected devices; and (d) a bilateral fitting paradigm.

Full Description:
The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/313,694, filed Aug. 20, 2001, which application, including its Appendix A, is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to bionic ear implants, and more particularly to an ear level high resolution bilateral programming system for use with a bionic ear implant. 
     A new generation of cochlear implants, commonly referred to as a “bionic ear” implant, has recently been introduced to the cochlear implant community. A representative bionic ear implant is the CII Bionic Ear™ cochlear implant system introduced by Advanced Bionics Corporation, of Sylmar Calif. A bionic ear implant is capable of delivering electrical stimulation to a patient at rates and resolutions which surpass that of conventional cochlear implants. 
     Early research indicates that cochlear implant patients will benefit from additional synchronized and processed speech information conveyed to the brain via both the right and left auditory nerve pathways. Several configurations are available to implement such a system, including, e.g.: (a) bilateral implants controlled by a single master speech processor; (b) bilateral implants driven by independent external speech processors; and (c) bilateral implants driven by synchronized external speech processors. The present invention relates primarily to configurations (b) &amp; (c). 
     Of significance to configuration (c) is its ability to interface with patients who use presently available technology platforms; specifically ear level early-generation speech processors. (The early-generation speech processors are referred to herein as “CI” processors, whereas the more recent bionic ear processors are referred to as the “CII” processors.) With or without a hardware change to a standalone behind-the-ear (BTE) processor, there is a need for an adapter module whereby two standalone BTE units may be synchronized both temporally and tonotopically to maximize the Cl patients listening experience. There is also a need for a peer-to-peer network and protocol consisting of two BTE units during normal operation, or two BTE units plus a host controller (PC, PDA, etc. . . . ) during a fitting session. 
     SUMMARY OF THE INVENTION 
     The present invention addresses the above and other needs by providing an adapter module that allows two standalone BTE units to be synchronized both temporally and tonotopically in order to maximize the CI patients listening experience. Further, the present invention provides a peer-to-peer network and protocol that consists of two BTE units during normal operation, or two BTE units plus a host controller (PC, PDA, etc. . . . ) during fitting. 
     The system provided by the invention includes (a) a communications interposer adapted to be inserted between the BTE battery and the BTE housing or modified BTE devices; (b) a communication channel over which communication takes place between the connected devices, including the protocol governing access to such channel; (c) the synchronization mechanisms used to achieve synchronization between the connected devices; and (d) a bilateral fitting paradigm. Each of these four components of the invention are summarized below. 
     (a) Communications Interposer. The communications interposer is a plug-in module designed for use with the Clarion® BTE (a CI device). It interfaces mechanically to the existing clinicians programming interface (CPI) contacts found on the underside of a standard platinum series BTE. The interposer module contains the interface electronics to the physical layer (any necessary antennae or connectors) and a replicated battery port on its underside to allow insertion as usual of a BTE battery. 
     (b) Communication Channel. The communication channel may be a wired or wireless link configured to use proprietary technology (e.g. the implantable speech processor&#39;s 10.7 MHz ITEL channel) or industry standard channels (e.g. the newly allocated 400 MHz medical band, Bluetooth, 802.11, etc. . . . ). One preferred embodiment uses wired interconnections of multiple speech processors and a fitting station via the buffered serial ports that are standard on Texas Instruments DSP products. In the case of wired links, interference is not a problem and the fundamentals of an enhanced packet protocol are utilized. For a wireless embodiment, bandwidth and interference issues bound the ultimate capability and robustness of the system. Any time there is a need to maintain communications in real time between two operating processors, there are many tradeoffs to consider, leaving certain implementations fundamentally superior to others. Conversely, developing new applications to run over an industry standard link utilizing industry standard protocols (e.g. Bluetooth) may simplify the development of new applications. 
     (c) Synchronization. The raw bandwidth and necessary protocol overhead of a chosen physical medium dictates the nature of information that can be passed over the network in real time. This, in turn, limits the degree to which parallel speech processors can synchronize their activities and/or share information. In a preferred embodiment, a maximally efficient data link layer is used that allows for arbitrary data exchange and device synchronization. Disadvantageously, varying degrees of reduced functionality are mandated as the system&#39;s communication bandwidth is reduced and/or as protocol overheads increase. To minimize such reduced functionality, several steps are taken. First, a fitting mechanism is used that tonotopically ranks electrode contact position in the contra-lateral cochlea, followed by assignment of audio frequency bands to those optimal contacts. Second, an operational mode is used that offers noise cancellation and directional hearing by making use of phase information available from the contra-lateral microphones. Third, an operational mode is described for listening in stereo. 
     (d) Bilateral fitting Paradigm. A fitting procedure, based on trans-cochlear pitch discrimination, is used so as to reduce channel interaction and optimally interleave channel information across available electrode contacts. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings, wherein: 
         FIG. 1  is shows a simple binaural interposer; 
         FIG. 2  shows a binaural programming cable suitable for use with a Clinician Programming Interface (CPI) device; 
         FIG. 3  depicts a BioNet BTE interposer; 
         FIG. 4  shows a BioNet Wireless BTE communications controller; 
         FIG. 5  depicts a first configuration for a binaural fitting cable; 
         FIG. 6  illustrates a second configuration for a binaural fitting cable; 
         FIG. 7  illustrates a third configuration for a binaural fitting cable; 
         FIG. 8  shows a fourth configuration of a fitting cable; 
         FIG. 9  shows a binaural standalone approach; 
         FIG. 10  depicts a wired binaural fitting mode; 
         FIG. 11  shows a BioNet Wireless fitting system. 
         FIG. 12  illustrates a cascaded master/slave bootload operation; 
         FIG. 13  shows stimulation synchronization; 
         FIG. 14  depicts audio synchronization; 
         FIG. 15  illustrates a fitting system framework; and 
         FIG. 16  conceptually illustrates a bilateral fitting paradigm. 
     
    
    
     Additional details regarding the CII Bionic Ear™ implant, and the BioNet, or communications network, that may be established between two bionic ears, or other biotechnology-based devices, in accordance with the present invention, including case studies and performance data, may be found in Appendix A of the earlier-referenced provisional patent application Ser. No. 60/313,694; filed Aug. 20, 2001, previously incorporated herein by reference. 
     Corresponding reference characters indicate corresponding components throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention. 
     Turning first to  FIG. 1 , there is shown a simple binaural interposer  23  that may be used as part of the invention. The BTE speech processor  22  is normally connected to a removable battery  24 . To insert the interposer  23 , the battery  24  is removed from the BTE processor  22 , and the interposer  23  is inserted between the BTE processor  22  and the battery  24 . The battery  24  may then be connected to the underneath side of the interposer  23 . 
     The interposer  23  has a BTE interface port  25  on the side thereof that is placed against the BTE processor. Such interface port allows electrical connections to be made with the circuits within the BTE processor. A binaural communications port  26  is on one side of the interposer  23 . This port, used for a wired implementation, allows a cable to be attached thereto that connects with another BTE processor, or to a programming device, such as a host fitting station. Power connections or terminals are also provided on the interposer  23  so as to allow the power terminals on the battery  24  to make electrical connection with the power input terminals on the BTE speech processor  22 . Thus, Power In terminals are located on a side  27  of the interposer  23  that is placed adjacent the battery terminals, and Power OUT terminals are located on a side  28  of the interposer that is placed adjacent the BTE processor, thereby allowing power to pass through the interposer from the battery to the BTE processor. 
     Turning next to  FIG. 2 , an enhanced binaural interposer  30  is depicted that includes a binaural CPI programming cable  32  exiting from a bottom side thereof. The acronym CPI stands for “clinician programming interface”, and refers to a special interface unit that allows the clinician&#39;s programmer (usually a laptop computer) to interface with the BTE processor that is being programmed. The CPI programming cable  32  is an extension to an existing BTE/CPI Programming Cable. On one end it is terminated with a standard DB15 connector for connection to a standard CPI-2. On the other end, it is terminated with the enhanced binaural interposer  30 . The enhanced interposer  30  performs CPI signal level shifting, power distribution and BSP (body speech processor) interconnection between a Master BTE (to which the interposer is attached), a slave BTE (to which the interposer is tethered) and the CPI (host PC). This is used for wired fitting of the system. Multiple variations of the enhanced interposer  30  are possible, as described, e.g., in  FIGS. 5 ,  6  and  7 , below. The fitting system is embodied in a “Wired Binaural Fitting Mode”. 
     Next, with reference to  FIG. 3 , a BioNet BTE interposer  40  is shown. The interposer  40  houses a wireless transceiver (Bluetooth, ISM, Medical Band, FIS ITEL, etc. . . . ) for wireless communication between binaurally co-joined BTE&#39;s and/or a host fitting station. The interposer  40  includes the same or similar connectors, e.g., Power In, Power Out, BTE interface port  25 , binaural cable port  26  (optional), and further includes an optional CPI programming cable port  42 . In a singular mode, the wireless link provided through the wireless transceiver can be used to fit a remote BTE. A more powerful mode provided by the interposer  40  is simultaneous fitting of synchronized BTE pairs. 
     A block diagram of the control subsystem necessary to implement a BioNet is shown in  FIG. 4 . That which is shown in  FIG. 4  functionally represents the circuitry contained within the interposer  40 . As seen in  FIG. 4 , a control module  44  interfaces with the local BTE  22  and local battery  24  through the BTE interface port  25  and power connections. Internal to the interposer  40 , the control module  44 —typically realized from microprocessor circuitry—interfaces with both a wireless network interface module  43  and a wired network interface module  46 . The wireless network interface module  43  has an antenna coil  45  connected thereto. Such antenna coil  45  is advantageously embedded within the housing of the interposer  40  so that it is not obtrusively visible to a user of the BioNet, which BioNet is made possible by the interposer  40 . The wireless network interface module  43  may connect to one or more remote BTE&#39;s. The wired network interface module  46  may connect to a remote BTE through the binaural cable port  26 , or to a host fitting system through the CPI programming cable port  42 . 
       FIG. 5  illustrates a standalone wired interconnection of two BTE&#39;s, a master BTE  22 , and a slave BTE  22 ′, via simple binaural interposers  23  and  23 ′, and a binaural interface cable  21 . The wiring of the binaural interface cable  21  is illustrated in  FIG. 9 . 
       FIGS. 6 ,  7  and  8  respectively show variations of a master BTE  22  connected to a slave BTE  22 ′. In  FIG. 6 , an enhanced interposer  30  connects the master BTE  22  to a CPI device  52 , while a binaural interface cable  21  connects the slave BTE  22 ′ to both the CPI  52  and the master BTE  22  through a simple interposer  23 ′. In  FIG. 7 , a BioNet BTE interposer  40  connects the master BTE  22  to a CPI device  52 , while a binaural interface cable  21  connects the slave BTE  22 ′ to both the CPI  52  and the master BTE  22  through a simple interposer  23 ′. In  FIG. 8 , two enhanced interposers  30  and  30 ′ are used to respectively connect a primary BTE  22  and a secondary BTE  22 ′ to respective CPI&#39;s  52  and  52 ′. Dual Port Fitting Software  54  interfaces with each of the respective CPI&#39;s  52  and  52 ′. 
     Turning next to  FIG. 10 , a wired binaural fitting mode is illustrated. A slave BTE  22 ′ is connected through, e.g., a simple interposer  23 ′ and a synchronous binaural interface cable  21  to an enhanced interposer  30 . The enhanced interposer  30  is connected to a master BTE  22 . The binaural fitting cable  32  that exits from the enhanced interposer  30  (see  FIG. 2 ) is connected to a CPI device  52 . The CPI device  52 , in turn, is connected to a host programming system, e.g., a laptop computer (not shown) loaded with the appropriate fitting software. 
     Next, with reference to  FIG. 11 , a BioNet Wireless Fitting System is illustrated.  FIG. 11  embodies the operational modes for fitting and operating a wireless BTE fitting system. As seen in  FIG. 11 , the system consists of two BioNet BTE Interposers  40 , each connected to a respective BTE  22 , and a BioNet PC Card  56  plugged into the host fitting station  58 . As thus configured, a BioNet  60  is created that allows either BTE to be coupled to the host fitting station  58 , and that further allows either BTE to be coupled to the other BTE. 
       FIG. 12  illustrates the preferred cascaded Master/Slave bootload operation relative to a CPI device, a Master BTE and a Slave BTE. As seen from  FIG. 12 , in keeping with the architecture of present day speech processors, a cascaded bootload scenario is presented whereby cable interconnection as per “Fitting Cable Configuration # 2 ”,  FIG. 6 , is employed. The “Command/Response” handshaking is defined in the serial link protocol and is presently controlled from the PC side by PPMIF.DLL (or equivalent). First, the need to utilize multiple target addresses (destination field in the packet protocol) is required. Secondly, monitor functions running on the DSP require master &amp; slave awareness with all incoming commands (from the host) delivered to the master for processing or forwarding (based on destination address) and all acknowledges to the PC delivered from the slave (directly or by way of forwarding from the master). 
     The key to the startup is a double blind bootload. That is, bootloading is a blind process, the success of which cannot be determined until the operation is complete and a PING is received from the remote kernel. In one binaural configuration, this blind operation is cascaded. For the BTE processor to become operational, a bootload to the master is performed (identical to the present day single speech processor environment). Upon completing the master bootload sequence, the slave bootload sequence is forwarded by the now operational master BTE to the slave BTE. Once both BTE&#39;s have been bootloaded, success can be determined by issuing a PING to the master BTE. The ping response is routed through the slave BTE and returned to the host PC through the CPI. Receipt of this acknowledgment indicates success. 
     Once a bootload has been successfully made, application programs can be loaded as per an existing packet protocol with the caveat that destination addresses will determine which BTE processor processes each command. 
       FIG. 13  illustrates how stimulation synchronization is obtained between the Master BTE and the Slave BTE. 
       FIG. 14  shows the manner in which audio synchronization is obtained between the Master BTE and the Slave BTE. 
       FIG. 15  depicts a fitting system platform. Such platform allows operation with the various binaural speech processor configurations described above. The platform includes a host fitting station  58 , typically comprising a laptop computer loaded with the appropriate fitting software. Also included in the platform is a BioNet PC card  56 , or equivalent, that is plugged into the fitting station  58 , thereby allowing communications with two BTE&#39;s  22 , one BTE being for the left ear and the other BTE being for the right ear. Each BTE is coupled to a headpiece  21 . The headpiece  21 , in turn, is coupled to the bionic ear implant  18 , which implant includes an electrode array  19 . A multiplicity of electrode contacts, e.g.,  16  electrode contacts, are spaced apart along the length of the array  19 , thereby allowing stimulation of cochlea tissue to occur at various locations along the length of the array. 
     Fundamental to the platform shown in  FIG. 15  are means to perform bilateral pitch ranking and channel allocation. This process of pitch ranking is illustrated in  FIG. 16 , and is further explained in Appendix A of the above-referenced provisional patent application Ser. No. 60/313,694, filed Aug. 20, 2001, previously incorporated herein by reference. 
     While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.

Technology Classification (CPC): 0