Transcutaneous interface device for use in cochlear implants

Abstract

The invention relates to the field of neurosurgical implants, and more particularly to methods for developing, tuning and studying a transcutaneous interface. The present device for analyzing data transmitted via a transcutaneous interface in prosthetic systems is a hardware / software system capable of digitizing, processing, saving and analyzing data transmitted via a wireless transcutaneous interface between different parts (1, 3) of a prosthetic system, said hardware / software system consisting of a receiving coil (5), a forward telemetry signal extraction module (6), a back telemetry signal extraction module (7), and a microcontroller (8) with software that operates in stream recording mode and data extraction mode, said microcontroller being connected via a communication channel to a personal computer (9) with preinstalled software for saving, visualizing and analyzing received data. The technical result of the invention consists in reducing the time required to develop and tune a wireless transcutaneous interface of a prosthetic system by using a circuit of a forward telemetry receiver that demodulates an encoded digital signal, a back telemetry receiver circuit that demodulates a frequency-modulated signal, and software that permits the recording and analysis of forward and back telemetry data.

Description

[0001] DEVICE OF PERCUTANEOUS INTERFACE IN COCHLEAR

[0002] IMPLANTS

[0003] AREA OF TECHNOLOGY

[0004] The invention relates to the field of neurosurgical implants, namely to methods for developing, debugging and studying a transcutaneous interface that transmits data via a wireless interface between different parts of a prosthetic system, in particular, between the wearable and implantable parts of neurosurgical implants, including cochlear implants.

[0005] LEVEL OF TECHNOLOGY

[0006] A class of prosthetic systems that stimulate the patient's nervous tissue by generating electrical impulses through electrodes implanted in the tissue is widely used in clinical practice. Some such systems, in particular cochlear implants, consist of an external wearable part and an internal implantable part.

[0007] The wearable part of the implant performs the function of powering the entire system, as well as measuring and converting, in accordance with the selected encoding strategy, a certain physical quantity into a digital code containing all the characteristics of the electrical stimulation used by the implantable part of the implant to convert the measured objective physical quantity into subjective sensations of the patient. Examples of the measured physical quantity may be graphic or acoustic information intended to excite the patient's sensation of an image or sound, respectively. The digital code transmitted from the wearable part to the implantable part is called direct telemetry. In some cases, it is necessary to additionally measure certain physical quantities on the side of the implantable part and transmit the measured values ​​to the wearable part of the implant to adjust the encoding strategy or for research purposes.The digital code transmitted from the implanted part to the wearable part is called reverse telemetry.

[0008] Thus, in general, a transcutaneous interface of a prosthetic system can be designed to transmit energy and direct telemetry from the wearable to the implantable part and to transmit reverse telemetry from the implantable to the wearable part. One of the common methods for implementing a transcutaneous interface is a pair of coils in resonance. One of the coils is a component of the wearable part of the implant, while the second is a component of the implantable part. Excitation of electromagnetic oscillations in the coil of the wearable part leads to excitation of electromagnetic oscillations in the coil of the implantable part, where a rectifier circuit is implemented, extracting energy from the electromagnetic oscillations of the coil, and thus powering the implantable part.

[0009] The most common method of transmitting direct telemetry via a transcutaneous interface is amplitude modulation: the transmission of a logical one is carried out by turning on the electromagnetic oscillations of the coil of the wearable part, and a logical zero is transmitted by turning off the electromagnetic oscillations. Some implementations of the transcutaneous interface use additional preliminary modulation of the digital signal, for example, the Manchester code or the code without returning to zero.

[0010] The transmission of measured physical quantities from the implanted part to the wearable part (reverse telemetry) can be carried out in various ways. One of these methods is frequency manipulation, in which the carrier signal frequency changes abruptly depending on the values ​​of the symbols of the information sequence.

[0011] In the research and development of prosthetic systems consisting of wearable and implantable parts, communication is established via a transcutaneous interface that transmits energy, forward and, optionally, reverse telemetry, after which the influence of various settings on the system elements is studied and the behavior of individual parts is analyzed depending on the input data. The main tool used to analyze the operation of a wireless transcutaneous interface is usually an oscilloscope. However, the use of an oscilloscope may not be possible when long-term measurements with high data transfer rates are required, as well as for analyzing streaming data in real time. Also, an oscilloscope excludes the possibility of demodulation and streaming analysis of non-standard protocols, which complicates the analysis of data transmitted via the transcutaneous interface.

[0012] The problem solved by the proposed invention is the creation of a hardware and software complex that allows for the analysis of data transmitted through a transcutaneous interface in prosthetic systems being researched and developed in real time and the receipt of the results of such analysis in digital form.

[0013] DISCLOSURE OF INVENTION

[0014] The technical result of the invention consists in reducing the time for developing and debugging a wireless transcutaneous interface of a prosthetic system due to the use of a direct telemetry receiver circuit that demodulates an encoded digital signal, a reverse telemetry receiver circuit that demodulates a frequency-modulated signal, and software that allows recording and analyzing direct and reverse telemetry data both in real time and after the recording of direct and reverse telemetry signals has been completed.

[0015] The technical result is achieved in a device for analyzing data transmitted via a transcutaneous interface in prosthetic systems, which is a hardware and software complex designed with the ability to digitize, process, store and analyze data transmitted via a wireless transcutaneous interface between different parts (1, 3) of the prosthetic system, consisting of a receiving coil (5), a direct telemetry signal extraction module (6), a reverse telemetry signal extraction module (7), a microcontroller (8) with software (hereinafter referred to as software) operating in a streaming recording mode and a data extraction mode, connected via a communication channel to a personal computer (9) (hereinafter referred to as PC) with pre-installed software (hereinafter referred to as PC software) for storing, visualizing and analyzing the received data.

[0016] The direct telemetry signal extraction module (6) may consist of a rectifier unit (10), a signal level generator unit (11) and a comparator unit (12) and may be designed with the ability to extract a digital direct telemetry signal and transmit it to a microcontroller (8) that performs digitalization and processing of the direct telemetry signal.

[0017] The module for extracting the reverse telemetry signal (7) may consist of a filter unit (13), an amplifier unit (14) and a demodulator unit (15) and may be designed with the possibility of extracting a digital reverse telemetry signal and transmitting it to a microcontroller (8), which additionally performs digitalization and processing of the reverse telemetry signal.

[0018] The software of the microcontroller (8) can be implemented with the possibility of demodulating a digital signal and / or checking the format of the transmitted data, and / or checking the checksum of the digital data and the parity bit of the digital signals. The software of the microcontroller (8) can be implemented with the possibility of forming, in the stream recording mode, a continuous data stream, bit-by-bit equal to the data transmitted in the forward and reverse telemetry and transmitted to the mentioned software of the PC.

[0019] The microcontroller software (8) can be designed with the ability, in the stimulation data extraction mode, to extract only the stimulation data from the data transmitted in direct telemetry, form a continuous stimulation data stream from them and transmit it to the mentioned PC software.

[0020] The PC software in stream recording mode is designed with the ability to record streams of direct and reverse telemetry data into a file, open and view recorded files of direct and reverse telemetry streams, process them in accordance with the selected data transfer protocols, and save the processing results in a readable form for subsequent analysis.

[0021] The PC software in the stimulation data extraction mode is designed with the ability to record stimulation data streams into a file, open and view recorded stimulation data stream files, and present stimulation data in a form convenient for perception and analysis.

[0022] ILLUSTRATIONS

[0023] The claimed invention is explained by figures, which depict the following: Fig. 1 is a block diagram illustrating the principle of connecting the components of a prosthetic system through a transcutaneous interface and a method for developing, debugging and studying this interface, Fig. 2 is a block diagram illustrating one of the possible implementations of a direct telemetry signal extraction module, Fig. 3 is a block diagram illustrating one of the possible implementations of a reverse telemetry signal extraction module, Fig. 4 is an illustration of an example of a basic diagram for extracting a direct telemetry signal.

[0024] The numbers indicate the following:

[0025] 1 - external wearable part of the prosthetic system,

[0026] 2 - coil,

[0027] 3 - internal implantable part of the prosthetic system,

[0028] 4 - coil,

[0029] 5 - receiving coil,

[0030] 6 - direct telemetry signal extraction module,

[0031] 7 - reverse telemetry signal extraction module, 8 - microcontroller,

[0032] 9 - PC,

[0033] 10 - rectifier block,

[0034] 11 - signal level generator block,

[0035] 12 - comparator block,

[0036] 13 - filter block,

[0037] 14 - amplifier block,

[0038] 15 - demodulator block.

[0039] DETAILED DESCRIPTION OF THE INVENTION

[0040] The invention is a technical means for developing, debugging and researching a transcutaneous interface that transmits data via a wireless interface between different parts of a prosthetic system.

[0041] The device for analyzing data transmitted via a transcutaneous interface consists of a receiving coil (5), a forward telemetry signal extraction module (6), a reverse telemetry signal extraction module (7), a microcontroller (8) with software coupled via a communication channel to a PC (9) with pre-installed PC software. The coil (5) can be structurally implemented as a single circuit or as two independent circuits for capturing forward and reverse telemetry signals. The forward telemetry signal extraction module (6) consists of a rectifier unit (10), a signal level shaper (I) unit, and a comparator unit (12). One of the possible implementations of the rectifier unit (10) consists of installing a diode in the signal line, another - in installing a diode bridge. The reverse telemetry signal extraction module (7) consists of a filter unit (13), an amplifier unit (14), and a demodulator unit (15).

[0042] The forward telemetry signal extraction module (6) and the reverse telemetry signal extraction module (7) are connected by wire to the microcontroller (8), on which software is implemented with the possibility of synchronous digitization of forward and reverse telemetry signals in one of two modes: in the streaming recording mode or in the stimulation data extraction mode. In addition, this software is configured to form a continuous data stream in the streaming recording mode, bit-by-bit equal to the data transmitted in the forward and reverse telemetry and transmitted to the PC (9). This software is also configured to extract only stimulation data from the data transmitted in the forward telemetry after the said processing of the received signals, in the stimulation data extraction mode, to form a continuous stimulation data stream from them and transmit it to the PC (9).Additionally, this software can be implemented with the ability to check the format of transmitted data, as well as check the checksum of digital data and the parity bit of digital signals.

[0043] The microcontroller (8) is connected via a communication channel to a PC (9) with pre-installed PC software with the ability to save, visualize and analyze received data. Additionally, the PC software is designed with the ability to record direct and reverse telemetry data streams in a file in the stream recording mode and / or stimulation data extraction mode, open and view already recorded direct and reverse telemetry stream files, process them in accordance with the selected data transfer protocols and save the processing results in a readable form for subsequent analysis.

[0044] The application of the device is considered on the example of a transcutaneous interface used in cochlear implants, but can also be used to analyze data transmitted through a transcutaneous interface of other types of prosthetic systems. The device operates as follows.

[0045] During the operation of the prosthetic system by the user, there is a continuous transmission of energy and data from the wearable part (1) towards the implantable part (3) (the so-called direct telemetry), as well as a transmission of data from the implantable part (3) towards the wearable part (1) (the so-called reverse telemetry) by means of the coils (2, 4) in resonance. The signal received from the coil (5) by means of the electromagnetic field from the coils (2) and (4) of the prosthetic system is fed to the direct telemetry signal extraction module (6) and the reverse telemetry signal extraction module (7), respectively. At the input of the direct telemetry signal extraction module (6), a rectifier block (10) is implemented, consisting of a diode bridge loaded with a resistor and a capacitor, so as to smooth out all oscillations of the forward telemetry carrier and extract the signal envelope.The envelope signal is fed to the signal level shaper block (11), which is necessary for adjusting the comparator level of the comparator block (12), equal to half the amplitude of the envelope signal. Using the signal level shaper block (11) together with the comparator block (12) allows to extract the digital envelope signal in a wide range of amplitudes of the high-frequency direct telemetry signal fed to the input. The extracted digital direct telemetry signal is fed to the input of the microcontroller (8).

[0046] At the input of the reverse telemetry signal extraction module (7), the signal received from the coil (5) enters the filter unit (13) with a frequency suppression band for the forward telemetry signal, then the signal enters the amplifier unit (14) and the demodulator unit (15). The extracted digital reverse telemetry signal enters the input of the microcontroller (8).

[0047] After processing the received signals, the software can form a continuous data stream in the stream recording mode, bit-by-bit equal to the data transmitted in the forward and reverse telemetry and transmitted to the PC software. This mode is intended for retransmitting the forward and reverse telemetry streams to the PC software unchanged. The PC software saves all bits of the forward and reverse telemetry data for subsequent analysis and provides the ability to analyze previously saved data. This operating mode allows extracting from the forward and reverse telemetry data all control sequences, control and command words, parity bits and checksums, write and read commands, and bits of data transmitted in both directions.

[0048] The stimulation data extraction mode is designed to extract from direct telemetry only those data that are used to stimulate the nervous tissue with electrodes. In this case, the microcontroller side (8) implements a check of the parity bit and checksums (if any), which ensures the integrity of the received data and eliminates random errors that may occur when receiving a direct telemetry signal. In this mode, the PC software saves stimulation data for subsequent analysis and provides the ability to present stimulation data in a form convenient for perception and analysis. In this mode, it is also possible to display stimulation data in real time, which can significantly simplify the development, debugging and research of data transmitted through the transcutaneous interface.

[0049] The device mode is selected using a switch on the board or the device body.

[0050] Example: the basic diagram (see Fig. 4) of the direct telemetry signal extraction module can operate as follows: from the direct telemetry receiving coil L1, the carrier frequency signal, amplitude-modulated by the useful signal, is fed to the rectifier, implemented on the diode bridge VD1, loaded on R1 and C1. The ratings are selected in such a way as to smooth out the carrier frequency oscillations and extract the useful signal envelope. A voltage divider is implemented on resistors R2 and R3, of equal resistance. Capacitor C2 is necessary for forming the reference signal level with automatic adjustment. Diode VD2 does not allow capacitor C2 to discharge during pauses in the input signal. Signals from the outputs of the divider and rectifier are fed to comparator U1, at the output of which the useful digital signal is restored, which is fed to the digital input of the microcontroller.

Claims

CLAUSE OF THE INVENTION 1. A device for analyzing data transmitted via a transcutaneous interface in prosthetic systems, which is a hardware and software complex designed with the ability to digitize, process, save and analyze data transmitted via a wireless transcutaneous interface between different parts (1, 3) of the prosthetic system, consisting of a receiving coil (5), a module for extracting a direct telemetry signal (6), a module for extracting a reverse telemetry signal (7), a microcontroller (8) with software operating in a streaming recording mode and a data extraction mode, connected via a communication channel to a personal computer (9) with pre-installed software for storing, visualizing and analyzing the received data.

2. The device according to claim 1, in which the direct telemetry signal extraction module (6), consisting of a rectifier unit (10), a signal level generator unit (11) and a comparator unit (12), is designed with the possibility of extracting a digital direct telemetry signal and transmitting it to a microcontroller (8) that performs digitalization and processing of the direct telemetry signal.

3. The device according to claim 1, in which the module for extracting the reverse telemetry signal (7), consisting of a filter unit (13), an amplifier unit (14) and a demodulator unit (15), is designed with the possibility of extracting a digital reverse telemetry signal and transmitting it to a microcontroller (8), which additionally performs digitalization and processing of the reverse telemetry signal.

4. The device according to claim 1, in which the software of the microcontroller (8), providing synchronous digitalization of the forward and reverse telemetry signals, is designed with the possibility of demodulating the digital signal and / or checking the format of the transmitted data, and / or checking the checksum of the digital data and the parity bit of the digital signals.

5. The device according to item 1, in which the said microcontroller software (8) is designed with the possibility of forming, in streaming recording mode, a continuous data stream, bit-by-bit equal to the data transmitted in forward and reverse telemetry and transmitted to the said software on the PC (9).

6. The device according to item 1, in which the said microcontroller software (8) is designed with the ability, in the stimulation data extraction mode, to extract only the data from the data transmitted in direct telemetry stimulation, form a continuous flow of stimulation data from them and transmit it to the mentioned software on the PC (9).

7. The device according to item 1, in which the mentioned software on the PC (9) in the stream recording mode is designed with the ability to record streams of direct and reverse telemetry data into a file, open and view recorded files of direct and reverse telemetry streams, process them in accordance with selected data transmission protocols and save the processing results in a readable form for subsequent analysis.

8. The device according to claim 1, in which the mentioned software on the PC (9) in the stimulation data extraction mode is designed with the ability to record stimulation data streams into a file, open and view recorded stimulation data stream files, and present stimulation data in a form convenient for perception and analysis.

Images