WO2017081335A1 - Device, method and computer program for generating one or more signals for the electrical stimulation of the saccule and utricle of a patient - Google Patents

Abstract

The invention relates to a device (12) for generating one or more signals for the electrical stimulation of the vestibular apparatus (saccule, utricle) of a patient. The device is characterised by comprising: a processing unit (17) for measurement signals provided by a measuring unit (11) comprising at least three accelerometers (14a) for providing measurement signals of acceleration and three giroscopes (14b) for providing measurement signals of angular velocity, said processing unit being configured to cancel the errors of the measurement signals; and a unit (18) for generating the one or more signals for the electrical stimulation of the vestibular apparatus of the patient from at least the measurement signals processed by the processing unit (17).

Description

 DEVICE, PROCEDURE AND COMPUTER PROGRAM TO GENERATE ONE MORE SACMUL-UTRICULAR ELECTRICAL STIMULATION SIGNS OF A PATIENT

The present description refers to the electrical stimulation of the vestibular apparatus of a patient. More specifically, the present description refers to procedures for generating one or more electrical stimulation signals of! vestibular apparatus of a patient. In addition, it also refers to devices and software to bait these procedures. STATE OF THE PREVIOUS TECHNIQUE

The vestibular apparatus, also known as the vestibular system, is the part of the inner ear and brain responsible for managing the balance and spatial control of an individual. The vestibular apparatus is formed by a system of semicircular canals, which indicate the movements of rotation, and by two widening called the saccule and the utricle, which indicate the linear accelerations. Basically, the latter report the position of the head with respect to the ground.

In this way, the vestibular apparatus is mainly responsible for sending signals to fas neuronal structures (cerebellum) that control the muscles that keep the individual in an upright position, which allows the individual to maintain balance in any situation, for example in displacements , turns or accelerations.

Therefore, a malfunction of this vestibular apparatus (for example, when the inner ear and / or the brain has been affected by a disease or accident) can give the individual a feeling of dizziness, nausea, vertigo and even insecurity and lack of security. I balance walking or making any movement.

Although in some cases the Individuals who suffer from these disorders are completely cured, in other cases these disorders are persistent, and the symptoms can be controlled with treatments but not eliminated completely, although it is common that neither the known treatments have an effect in some patients These treatments may consist of the administration of drugs, diets, physical therapy or, in severe cases, surgery may even be necessary ...

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REPLACEMENT SHEET (RULE 26) Therefore, there is a need for a device that at least partially solves the problems described above.

5 EXPLANATION OF THE INVENTION

In a first aspect, a device for generating one or more signals of electrical stimulation of the vestibular apparatus (more specifically, the saccule and the etricle) of a patient is described. The device may comprise:

10 * A measurement signal processing unit provided by a measurement unit comprising at least the following sensor elements:

 - Three accelerometers to provide acceleration measurement signals,

- Three gyroscopes to provide angular velocity measurement signals, the processing unit being configured to cancel the errors of the ir> measurement signals;

 * A unit generating the one or more electrical stimulation signals of the patient's vestibular apparatus, starting at least the measurement signals processed by the processing unit. o D this way, through this device you can electrically stimulate the neuron tissue! (through the vestibular apparatus) with the objective that the patient recovers the sensation of balance permanently, without requiring any type of medication or similar »Basically, for this, the provision of the measurement signals by the elements sensors (in total six measurement signals, three provided by the three 5 ceierometers and three provided by three gyros) and the processing of these measurement signals by the processing unit allows the measurement signals corresponding to warping to be obtained as a result , nodding and yawning of the patient, which indicated where the ground is with respect to itself. With at least these measurement signals (although it can also generate the electrical stimulation serial from these 0 processed measurement signals and certain patient characteristics), the generation unit is configured to generate at least one electrical stimulation signal to be applied to The patient's vestibular apparatus (more specifically, the stimulation signals will be applied over the region of the saccule and / or the region of the utricle, of its vestibular apparatus).

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REPLACEMENT SHEET (RULE 26) In some examples, the device may also comprise a unit for acomfeloncenting of the measurement signals provided by the measurement unit, this conditioning unit being configured to reduce the noise of these measurement signals before being processed by the processing uméaá . For this purpose, this conditioning unit may comprise one or more elements of filtering of the acceleration measurement signals provided by the accelerometers comprised in the unit of measurement and one or more elements of filtering of the angelar velocity measurement signals provided by the Gyros included in the unit of measure. These filtering elements can be, for example, median filters, media filters, atiaptatívos filters and / or maximum or minimum filters or a combination of both.

As previously mentioned, the unit of generation of the electrical stimulation signal of the patient's vestibular apparatus can be configured to generate the one or more electrical stimulation signals from the measurement signals processed by the processing unit and determined characteristics of the patient, such as the maximum stimulation current that the patient is able to withstand, the minimum stimulation current with which the patient is able to perceive the stimulus, the maximum range of stimulation frequencies and the minimum frequency range of stimulation It will be described below how this generation unit is capable of generating the one or more effective stimulation signals from all these cited data,

According to some examples, the processing unit may comprise an element configured to apply a Kaiman filter on the measurement signals, so that the processed measurement signals may comprise the pitch, bead and yaw measurement signals, more specifically , the application of a aiman filter is suitable to achieve more precise measurement signals from the combination of the measured signals provided by the sensor elements. It is important to emphasize that these sensor elements provide measurement signals with sometimes significant errors. With the application of the Kaiman filter, three measurements are obtained (pitch, warp and yaw), which can be assumed as correct.

REPLACEMENT SHEET (RULE 26) In some examples, the measurement unit may comprise as sensor elements three agnetrometers to provide signals measuring the intensity of the magnetic fields on each axis. Thus, the measurement signals provided by the metering unit are nine in total.

The presence of the magnetrometers is mainly due to the fact that they are essential sensor elements and have no drift. Thus, being known that accelerometers are very noisy sensors, that gyros give a good reading but suffer from drift and that magnetrometers are stable and have no drift, the accelerometers are corrected by gyroscopes, while gyroscopes are corrected. by the magnetrometers. Therefore, the presence of gynecopes magnetrometers is basically due to the measurement error of these sensor elements. The subsequent application of the alman filter on the measurement signals provided by these sensor elements, since it is a filter that combines the measurement signals of all the sensor elements, allows a more precise measurement to be obtained.

In the case of the presence of the magnetrdmeters in the measuring unit, the conditioning unit of the measuring signal may further comprise one or more fritting elements of the measurement signals of the intensity of the magnetic fields on each axis provided by the magnetrámatros included in the unit of measure. These filtering elements can be, for example, median filters, media filters, ad pta ive filters and / or maximum or minimum filters or a combination of both.

According to some examples, an electrical stimulation signal from the patient's vestibular apparatus generated by the generation unit may comprise a muitiygasic electrical pulse, which may comprise two or more pulses of alternating polarity, with varying amplitude and pulse width , during a period of duration of the electrical pulse and a time spacing between electrical impulses. In some examples, this mufllhasic electric pulse can be a biphasic pulse, one of the Impulses being positive and the other negative or the other way around (that is, it is alternating polarity), in which the pulse width and amplitude are ios same both in e! positive impulse as in the negative impulse, for each electrical stimulus.

REPLACEMENT SHEET (RULE 26) In some examples, the amplitude of stimulation of each electrical impulse may depend at least on the characteristics of the patient relative to the maximum stimulation current that the patient is able to withstand and the minimum stimulation current with which the patient is capable of perceiving e! stimulus. More specifically, the amplitude of each Impulse 5 can be obtained from the formula:

where lime * represents the maximum stimulation current that the patient is able to withstand, represents the minimum stimulation current with which the patient is able to perceive the stimulus and Si (in English, '' StímuMbñ L e) represents the level of stimulation at which the stimulation is to be performed, that is, the amplitude in which the patient experiences a comfortable level of stimulation. The amplitude of the stimuli can be kept constant at the percentage of the dynamic range (threshold, maximum minimum threshold) determined by the SL value

According to some examples, the period of time of! Electric pulse can depend at least on the characteristics of the patient relative to the maximum range of stimulation frequencies and the minimum range of stimulation frequencies. More specifically, the period of duration of the electrical pulse can be obtained from the formula:

?. $ where F _m¾s represents the maximum range of stimulation frequencies, F _f represents the minimum range of stimulation frequencies and § is a standard acceleration factor that depends on the processed measurement signals, that is, in some examples, of the warp, pitch and yaw measurement signals provided by the processing unit (for example, at the output of the filter of aman, if this is the one used in the unit of

30 processing}. More specifically, β can take values from -1 to 1, which correspond to the values of each of the warp, pitch and yaw measurement signals, with a maximum and a minimum (for example, -1 can correspond with a maximum warping to the right and 1 maximum warping to the left).

REPLACEMENT SHEET (RULE 26) On the other hand, if the period of time of the pulse-electric duration can also be obtained from the formulas:

₅ r - _j „ _g) for β e [cu]

~ e¾ for /? e [-1.0] where F _ms¾ represents the maximum range of stimulation frequencies, represents the 10th range of stimulation frequencies, β is a normalized acceleration factor that depends on the processed measurement signals and G represents the curvature of the function. Thus, depending on their curvature they allow the patient to be able to discriminate between two very small accelerations and that the very strong ones perceive them in almost the same way (at low acceleration values the patient perceives large changes between them).

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 In a second aspect, a device for generating one or more electrical stimulation signals of a patient's vestibular apparatus is described. The device may be configured to:

 * Process, by a processing unkfacJ, measurement signals m provided by a unit of measurement comprising at least the following sensor elements:

 - Three accelerometers to provide acceleration measurement signals,

- Three gyroscopes to provide angular velocity measurement signals, the processing unit being configured to cancel the errors of the

25 measurement signals;

 * Generate, by a generation unit, the un® or more electrical stimulation signals of the patient's vestibular apparatus from at least the measurement signals processed by the processing unit.

• 30 In addition, the device may also be configured to condition, for part of a conditioning unit, the measurement signals provided by the measurement unit, this conditioning unit being configured to reduce the noise of these measurement signals before being processed by the unlóaü processing.

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REPLACEMENT SHEET (RULE 26) According to another aspect, a procedure for generating one or more electrical stimulation signals of! vestibular apparatus of a patient. This procedure may include:

 * Process, on the part of a processing unit, measurement serials provided by a unit of measurement which comprises at least the following sensor elements:

 - Three accelerometers to provide acceleration measurement signals, ~ Three gyroscopes to provide angular velocity measurement serials, the processing unit being configured to cancel the errors of the measurement signals;

 * Generate, by a generating unit, the one or more electrical stimulation signals of the patient's vestibular apparatus from a! minus the measurement signals processed by the processing unit. In addition, this procedure may also include conditioning, on the part of a conditioning unit, the measurement signals provided by the measurement unit, this conditioning unit being configured to reduce the noise of these measurement signals before being processed by the processing unit. In yet another aspect, a computer program is described that may comprise computer instructions to cause a computer system to execute a procedure to generate one or more electrical stimulation signals from a patient's vestibular apparatus, such as the one previously deserted. This computer program may be stored in physical storage media, such as recording media, a computer memory, or a read-only memory, or it may be carried by a carrier wave, such as electrical or optical.

In another aspect, a computer system that can comprise a memory or processor is described, instructions executable by the processor being stored in the memory and these instructions comprising functionalities for executing a procedure to generate one or more electrical stimulation signals of! a patient's vestibular apparatus, as described above.

REPLACEMENT SHEET (RULE 26) According to another aspect, a system for stimulating a patient's vestibular apparatus by one or more electrical stimulation signals is described. This system can be an impiable device that can include:

 «A unit of measure that can comprise at least the following sensor elements:

^■ · Three aeeromeromers to provide acceleration measurement signals; - Three gyros to provide angular velocity measurement signals; * A device for generating one or more electrical stimulation signals of a patient's vestibular system such as that described above, from the measurement signals provided by the unit of measurement;

 »A unit for applying the electrical stimulation signals generated on the patient's vestibular apparatus.

In some examples, the unit of measurement may further comprise three magnetromereres as sensor elements to provide signals measuring the intensity of the magnetic fields on each axis.

According to some examples, the application unit may comprise an electrode plate. This electrode pad may comprise a plurality of electrodes, for example, between 7 and 12 electrodes.

In some examples, the electrode plate may be configured to dispose at least one electrode in the region of the saccule and at least one electrode in the utricule region of the patient's vestibular apparatus.

In some examples, the plurality of electrode may comprise at least one electrode configured to record the voltage produced by the vestibular nerve once the electrical stimulation is applied. Therefore, the system may use an electrode (or more) to perform the stimulation. , while with another electrode (or more) you can record the voltage produced by the vestibular nerve after stimulation. In this way, it is possible to know if the vestibular nerve has actually been stimulated {this functionality can be referred to as Telemetry of the Vestibular Response, in English Vestibular Respmse Teiemeiry - VRT).

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REPLACEMENT SHEET (RULE 26) In addition, the application unit may comprise a reference electrode, which may be configured to be disposed in the patient's mass.

According to some examples, the implant device may comprise an element s for the transmission and / or reception of energy, such as a first coil.

In some examples, the impiantable device may comprise an element for the transmission and / or reception of data, as well as a second coil. m In this case it is important to note that the first and second coils can be the same coil.

In some examples, the system may comprise a device external to the patient that may comprise

16 * A power supply;

 * An element for the transmission and / or reception of energy, connect to the power supply, such as a third coil.

According to some examples, the first coil of the impiantable device and the third 0 coil of the external device may be configured to establish an Inductive coupling.

On the other hand, the external device may comprise an element for the transmission and / or reception of data, such as a fourth coil.

In some examples, the second coil of the impiantable device and the fourth coil of the external device may be configured to establish an inductive coupling.

In the case that the first and second coils are the same coil, the third and fourth coils can be inductively coupled to this coil. On the other hand, if the third and fourth coils are the same coil, the first and second coils can be inductively coupled to this coil. In the event that the first and second coils are the same coil and the third and fourth coils are the same coil, these two common coils can be configured to inductively engage.

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REPLACEMENT SHEET (RULE 26) Other objects, advantages and features of embodiments of the invention will become apparent to those skilled in the art based on the description, or can be learned with the practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Particular embodiments of the present invention will now be described by way of non-limiting example, with reference to the accompanying drawings, in the following:

Figure 1 shows a block diagram of a system to stimulate the vestibular apparatus of a patient by one or more electrical stimulation signals according to some examples;

 Figure 2 shows a schematic diagram of the head of a patient in which the warping, nodding and winking movements are indicated according to some examples; Figure 3 shows a schematic diagram of an electrical stimulation signal of! a patient's vestibular apparatus according to some examples;

Figure 4 shows a schematic diagram of an electrode plate included in the system of Figure 1 according to some examples;

Figure 5 shows a block diagram from which it is possible to select the electrode to be used for electrical stimulation of a patient's vestibular apparatus, according to some examples;

Figure 6 shows a schematic diagram of the system shown in Figure 2, arranged in a patient according to some examples.

DETAILED EXHIBITION OF REALIZATION MODES

As can be seen in Figure 1, according to some examples, a system 10 for stimulating the vestibular apparatus of a patient by means of one more electrical stimulation signals can comprise an implanted device which in turn can comprise

- A unit of measure 11 for obtaining and providing different measurement signals;

 - A device 12 for generating the one or more electrical stimulation signals of the patient's vestibular apparatus from the measurement signals received;

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REPLACEMENT SHEET (RULE 26) - An application unit 13 of the one or more electrical stimulation signals generated, on the patient's vestibular apparatus.

The: measuring unit 11 may comprise the following sensor elements:

 - T is accelerometers 12a to obtain acceleration measurement signals;

 - Three gyros 12b to obtain angular velocity measurement signals

- Three magnetrornetros 12c to obtain signals measuring the intensity of the magnetic fields in each ej X, Y Z.

In this way, the measuring unit 11 has been designed in the present examples taking into account the use of three accel rometers 1 to {one for each X, Y and Z axis), of three gyroscopes 14b (one for each X axis , Y and Z) yd three magnetró etros 1 c fño for each axis X, Y and Z). The unit of measurement obtains the measurement signals of these accelerometers, gyroscopes and magnetrometers and provides them to the device 12 to generate one or more electrical stimulation signals.

E Important to note that, in some examples, the magnetrometers may not be part of the described sensor elements, the measuring unit 1 being thus formed by the three accelerometers 14a and the three gyroscopes 14b.

Accelerometers 14a are configured to provide linear acceleration measurement signals, which are perceived in the region of the saccule and in the region of the utricule of the patient's vestibular apparatus, gyroscopes 14b are configured to provide velocity measurement signals angular, the same as perceived in the semicircular canals of the patient's vestibular apparatus. The magnetrometers 1 c are configured to provide signals for measuring the intensity of the magnetic fields on each X »Y and Z axis. However, the measuring unit 11 obtains nine measurement signals, three for each type of sensor element.

At this point it is important to note that the unit of measurement may comprise different configurations at the level of sensor elements, so the number of measurement signals obtained will depend on the number of sensor elements present in the unit of measurement. Thus, as described above, in the previous examples the configuration is based on the presence of accelerometers, gyroscopes and magnetrometers, but any

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REPLACEMENT SHEET (RULE 26) Another type will set you up. For example, the measuring unit 11 could comprise only accelerometers, only gyroscopes, only agnetronometers or any other combination between types of sensor elements. It would also be possible to use other types of sensor elements than those described. Despite this, in the present examples, accelerometers can be considered fundamental and the presence of additional sensor elements (gyroscopes and magirometers) is given by measurement errors of these sensor elements, as will be described later.

As can also be seen in Figure 1, according to some examples, the device 12 to generate the one or more electrical stimulation signals of the patient's vestibular apparatus may include:

 ~ A unit for receiving the measurement signals provided by the unit 1 of measurement described above;

 ~ A unit 16 for conditioning the measurement signals received through the receiving unit;

 - A unit 1? of processing gives the signals of measurements conditioned by the unit 18 of conditioning;

 --- · A unit 18 for generating the one or more electrical stimulation signals of the patient's vestibular apparatus from the measurement signals processed by the processing unit 17;

 - A unit for the provision of one or more electrical stimulation signals generated by the generation unit 18.

The receiving unit is configured to receive the measurement signals provided by the different sensor elements that are part of the measuring unit 1 1. In this mode, this receiving unit can be an element disposed between the measuring unit and the conditioning unit 16 (for example, in the form of connectors or similar to those on which, on the one hand, the measuring unit is connected and, on the other hand, the conditioning unit is connected) or it may be integrated in the same conditioning unit (for example, if the conditioning unit is part of a processor or an electronic device, the receiving unit may be pins of the own processor or electronic device intended for the reception of measurement signals). In the latter case, the measurement unit may be connected directly to the conditioning unit 16,

REPLACEMENT SHEET (RULE 26) for example, by welding or any other fixing means and it could even be understood that this receiving unit does not exist in the device.

The conditioning unit 18 is configured to reduce the noise of the received • 5 measurement signals. According to some examples, this conditioning unit 18 may comprise a medium filter 203,2013,200, either one pair each type of measurement signal (i.e., a filter bank for the measurement signals obtained by the accelerometers , a filter bank for the measurement signals obtained by the gyroscopes and a filter bank for the measurement signals obtained by the magnetrometers) or a 10 for all the measurement signals received. In addition, these filter banks could also comprise, for example, media filters, adaptive filters, maximum or minimum filters or any combination thereof {also including any combination of these types of filter with medium filter}.

16 According to some examples, the conditioning unit 16 may not be present in the device 12. In this case, the measurement unit 11 could directly provide the measurement signals to the processing unit 17

This processing unit 17 may be configured to cancel the errors present 2S in the measurement signals received from the slow conditioning unit 18 (or directly from the measuring unit 11 if the conditioning unit is not present). According to some examples, this unit 1? The processing element may comprise an element for applying a Kaiman filter 21 to the measurement signals, which combines the measurement signals obtained by all the sensor-thermometers, gyroscope 25 and magnetromeres) in order to obtain more precise signals. The accelerometers are very loud sensors, the gyros give a good reading but suffer from drift and the magneirbometers are stable and have no drift. Thus, by applying the alman filter 21 _: the measurement signals of the accelerometers are corrected by the gyro measurement signals, and these gyro measurement signals are in turn corrected by the magnetrometers. After applying the Kalman filter you get three signals referenced as '' nodding '22 (e? I English' pic), "warping ^{" 0} 23 {in English, ^e rof). "Yaw ^* 24 (in English," and ^* }, which can be assumed to be correct (see Figure 2.) Thus, the movement ae could make a human being on an imaginary axis that passes in the direction formed between both ears (also known as lateral or transverse axis), is known

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REPLACEMENT SHEET (RULE 26) as nodding 22, £ 1 ovimiento that a human being could perform on an imaginary axis that runs between the anterior part of the head (the wax} and the posterior part of the head (also known as longitudinal axis), is known as warping 23 Finally, the movement that a human being could make on an imaginary axis that passes in the direction formed between the top of the head and the ground (also known as the vertical axis), is known as yaw 24. Basically, these Tre point to indicate the human being where the soil is located.

L unit 18 generating one or more signals of electrical stimulation of! The patient's vestibular apparatus may be configured to generate this one or more electrical stimulation signals from the measurement signals processed by the unit í? processing (i.e., pitch signals 22, warp 23 and yaw 24) and of different patient-related characteristics.

? 6 These patient-related characteristics may be, for example;

 - The maximum stimulation current that the patient is able to withstand;

 - The comment of minimum stimulation with which the patient is able to perceive the stimulus;

 - The maximum range of stimulation frequencies;

or - The minimum range of stimulation frequencies. Figure 3 shows an example of a muitic electric pulse 30 (according to some examples, these rnultiphasic electric pulses can be biphasic (two pulses of alternating polarity, in which the pulse width and amplitude are both in the positive pulse6) as in the negative impulse, for each electrical stimulus) or three-phase (three impulses}} that can be used as an electrical stimulus generated by the generation unit 18. This electrical pulse can be defined as a series of "rf electrical impulses 31 of alternating polarity , with amplitude 34. (in English, "Amplitu & e ^* and width 35 (in English," P & se H '/ íb ") of variable impulse, for a period of time 32 (English, ^* F m &Penod") and with a 0 spaced in time 33 (in English, "Ga ervaf}, Adjusts the duration 32 of the electric pulse {F m Per íj it is possible to vary the number of Impulses per second and, therefore, the frequency of stimulation. It is also to highlight wash reliable regarding the delay 36 (in English "Déiaf) of the pulse, which is the time that elapses before starting to generate the impulses, that is, the delay on the Start of the P nw Period (the duration of the pulse in the

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REPLACEMENT SHEET (RULE 26) weather}. These different components of the stimulus must be previously configured, for example by clinical staff) based on the patient's responses to different test stimuli.

Thus, an example of how the parameters of the patient and warp, pitch and yaw signals can intervene in the generation of electrical stimuli is described below (that is, in the configuration of the electrical stimulus variables). In this example, the variables are defined based on the criteria of the clinician or based on objective / subjective measures of! patient. So,

 - · Delay 36 (Defery) can be set by default to 0 milsseconds, without patient intervention;

 - time spacing 33 {Gap fntervai) can be defined by default to 8 milliseconds, without the intervention of the patient;

 -! at amplitude 34 (Amplitude®) can comprise two variables;

 o The minimum threshold with which the patient is able to perceive the stimulation; o The maximum stimulation threshold with which the patient is comfortable;

- The pulse width 35 (P is idift} can be defined by default to 26 microsaconds, but in case the patient needs more stimulus intensity, the pulse width value can be increased;

 - The duration 32 of the electrical pulse (Fr ame Pmod) according to physiological studies, the vestibular apparatus encodes the information by varying the frequency of the nervous pulse. This variable must be configured to obtain the maximum and minimum acceleration perceived by the patient;

The number of pulses can be defined, for example, at a two-phase pulse, without the intervention of the patient, more specifically, according to some examples, the period of duration of the electric pulse (fmm® Pmloé) can depend at least on the characteristics of the patient relative to the maximum range of stimulation frequencies and the minimum range of stimulation frequencies. More specifically, the period of duration of the electrical pulse can be obtained from the formula:

REPLACEMENT SHEET (RULE 26) where FÍHSX represents the maximum range of stimulation frequencies,. represents the minimum range of stimulation frequencies and β s a normalized acceleration factor that depends on the measured measurement signals, that is, in some examples, the warp measurement signals 23, pitch 22 and yaw 24 provided by the unit of processing (for example, at the output of the filter 21, if this is the one used in the processing unit 17).

On the other hand, the period of duration of the electric pulse can also be obtained from the formulas.

where Fm & x represents the maximum range of stimulation frequencies, ¾ represents the minimum range of stimulation frequencies, β is a normal acceleration factor that depends on the processed measurement signals (warping, pitching and yaw, as in the previous formula) and C represents the curvature of the function. Thus, the function, depending on its curvature, allows the patient to be able to discriminate between two very small accelerations and that the very strong one perceives them in almost the same way (that is, at low acceleration values the patient perceives large changes between they). With reference to the amplitude of stimulation of each electrical pulse, it can depend at least on the characteristics of the patient relative to the maximum stimulation current that the patient is capable of supporting and the minimum stimulation current with which the patient is able to perceive the stimulus More specifically, the amplitude of each impulse can be obtained from the formula:

where x represents the maximum stimulation current that the patient is able to withstand, U¾ _n represents the minimum stimulation current with which the patient is capable

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REPLACEMENT SHEET (RULE 26) of perceiving e! stimulus and SL (in English, "Stimuí & tíon L & vef} represents the level of stimulation at which the stimulation is to be performed, that is, the extent to which the patient experiences a comfortable level of stimulation. The amplitude of the stimuli can be maintained constant at! percentage of dynamic range {maximum threshold ~ minimum threshold) determined by the SL value

The provision unit of the one or more electrical stimulation signals may be configured to provide the one or more electrical stimulation signals generated by the generation unit 18 to the application unit 13. Thus, this provisioning unit may be an element disposed between the generating unit 18 and the application unit 13 of the one or more electrical stimulation signals (for example, in the form of collectors or similar to those which, by a on the other hand, the generation unit is connected and _v on the other side, the application unit is connected) or it can be integrated in the same generation unit (for example, if the generation unit is part of a processor or of a device electronic, the provisioning unit may be pins of the own processor or electronic device intended for the provision of the one or more electrical stimulation signals.} In the latter case _{* the} generation unit may be directly connected to the application unit _* by For example, by welding or any other fixing means, it could even be understood that this provisioning unit does not exist in the device.

The application unit 13 of the one or more electrical stimulation signals may comprise an electrode plate 40, this electrode plate 40 being formed by a support 41 and a plurality of electrode 42 {for example, between seven and twelve electrodes} tai as shown in Figure 4. The plate holder 41 may have a flat configuration.

This electrode plate 40 is the element of the system 10 that acts as a machine-nerve inferfaz. Its design is based on the surgeon's inability to place the electrodes in the exact region, so that it comprises the plurality of electrodes 42 arranged in a plane, so that at the time of its activation, ios that are better located and are Those responsible for applying the one or more electrical stimulation signals on the patient's vestibular apparatus, more specifically on the saccule region and the utricle region (both regions form the macula of the vestibular apparatus). In the case that its precise arrangement is possible on the region of the saccule and the region of the utricle (it is

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REPLACEMENT SHEET (RULE 26) say, on the macula), it would possibly be sufficient to use two electrodes for each X, Y and Z axis.

In addition, the plurality of electrodes 42 may comprise a! less an electrode configured to record the voltage produced by the vestibular nerve once the electrical stimulation has been applied. Therefore, the system can use one or more electrodes to perform the stimulation, while with another electrode (or more) it can record the voltage produced by the vestibular nerve after stimulation {WO ^* }. In this way, it is possible to know if it has really been possible to stimulate e! vestibular nerve

On the other hand, the application unit 13 can also comprise a reference electrode, which can be arranged in the patient's eimastoids.

In this way, one is the generating unit 18 has generated the one or more electrical stimulation signals, it is necessary to send to each electrode selected according to its position in the macula, the electrical stimulus. The positions of the electrodes in the macula are defined duí¾r> e the activation of the system 10 and can be generated, for example, a table, a repository or the like {it can be stored in for example a memory comprised in the system 10, more specifically in the implantable device) in which data concerning, patiently, which electrode stimulates which regions (saccule, utricle) of the vestibular apparatus are stored. Thus, for example, an electrode n1 (or more) of the plurality of electrodes 42 may be intended to stimulate the region of the macula that perceives accelerations in ee X, an electrode n2 (or more) of the plurality of electrodes 42 it may be intended to stimulate the region of the macula that perceives the accelerations in the Y axis, and an electrode n3 (or more) of the plurality of electrodes 42 may be intended to stimulate the region of the macula that perceives accelerations in the axis Z. These positions do not change once obtained (the clinical staff has to determine them beforehand. You will have a patient analysis), except for the implantable device, due to an accident, a strong broth, etc. Move from its original position. Therefore, once it is known which electrode it is necessary to stimulate, at the magnitude of the stimulus and the configuration of the stimulus, the generation unit 18 must proceed to the generation of the electrical stimulus and provide it to the corresponding electrodes of the electrode plate 40.

18

REPLACEMENT SHEET (RULE 26) Figure 5 shows a block diagram of the part of the generation unit 18 or allows to select the electrode required to perform the correct stimulation of the patient's vestibular apparatus (saccule, utricle), as can be seen in this figure, one of the inputs of the module 80 f which, for example, can be a kind of multiplexer or similar) are the warpage measurement signals 23, pitch 22 and yaw 24 obtained after the application of the Kaiman filter 21, while the other of the inputs are the data collected during the activation of the implantable device (once implanted), which define which electrodes stimulate which regions (saccule, utricle) of the vestibular apparatus and can be stored in the table cited above. Therefore, when it is intended, for example, to stimulate the vestibular apparatus with the information of the pitch 22, and it is necessary to obtain which electrodes are responsible for this stimulation and then the electrical stimulus is generated. The same goes for the rest of the measures.

The Impossible device may also comprise an element for the transmission and / or reception of energy, such as a first coil, the operation of which will be described later. In addition, the implantable device may comprise an element for the transmission and / or reception of data, such as a second coil. According to some examples, the coil of the element for the transmission and / or reception of energy and the coil of the element for the transmission and / or reception of data may be the same coil,

 twenty

The system 10 for stimulating the patient's vestibular apparatus, apart from the implantable device described up to this point, can also comprise an external device. This external device, in turn, may comprise a de..alimentación electronics system (both the external device and the implantable device) source, such as ^as' ba and IA: íftío ion, a nickel -cadmio, etc., as well as, an element for the transmission and / or reception of energy, such as a third coil, connected to the power supply. A EMAs _"This external device may also comprise an element for the transmission and / or reception of data, such as a fourth coil. According to some examples, the third coil of the element for the transmission and / or reception of energy and the 0 fourth coil of the element for the transmission and / or reception of data may be the same coil.

In the case that each of the implantable and external devices comprises a single coil, it is possible between them to establish an inductive coupling through the tissues

REPLACEMENT SHEET (RULE 26) Intermediates of the patient that allows, on the one hand, to make the necessary energy to power the electronics of the implantable device and, on the other hand, establish a two-way communication! t the eternal device the implantable device, from which it is possible to qualify data transfers,

In the case that the implantable device comprises the first and second coils and the external device comprises the third and fourth coils, two inductive couplings would be produced, one between the coils intended for the transmission and / or reception of energy (first and third coils) and another between the coils intended for the transmission and / or reception of data between the devices (second and fourth coils). It would also be possible to establish an inductive coupling between a single coil in one of the devices (that is, the same coil is used for the transmission and / or reception of energy and the transmission and / or reception of data) and two coils in the other device. (a first coil for the transmission and / or reception of energy and a second coil for the transmission and / or reception of data).

With reference to the transfer of bidirectional data between the implantable device and the external device, in the implantable device all the data (described above) necessary for the generation of the electrical stimulus, as well as certain commands are recorded (for example). especially as the start of the system calibration process.

The calibration process of the sensor elements is carried out at the first activation, before deciding which electrodes are to be stimulated, given that the sensors are implanted in the patient and are fixed. Thus, this should be done only during the activation of the implant, unless a strong blow, accident, etc. may cause the implantable device to move from its position. The calibration process basically consists of putting the patient's head in such a way that it is completely upright (that is, the patient has to be in a sitting or standing position, with a stiff head looking straight ahead). Thus, it is defined that this position is state 0, the system registering the values of its sensor elements (accelerometers, gyroscopes, magnetrometers). From these values, by means of a numerical calculation (a rotation matrix), the output of the measurement signals of the sensor elements to the position of the patient's head is calibrated.

twenty

REPLACEMENT SHEET (RULE 26) In the external device all the data generated and / or obtained in the implanted device are collected, such as the electrical impedance of the tissue for each “no of the electrodes, the response of the vestibular nerve to an electrical stimulus (VRT) or the state general of the imÃntantabie device.

Returning to the device 12 to generate the one or more electrical stimulation signals of the patient's vestibule apparatus from the obtained measurement signals, it is important to note that, from everything described, it can be seen that it can be configured to execute a procedure for generating one or more electrical stimulation signals on the vestibular apparatus of a patient. This procedure may include:

 »Conditioning, by the conditioning unit 16, the measurement lines provided by the measuring unit 11, this conditioning unit being configured to reduce the noise of these measurement signals before being processed by the unit 1? of processing and the unit of measurement comprising at least the following sensor elements:

 - Three oiled other 14a to provide acceleration measurement signals, »Three gyroscope 14b to provide angular velocity measurement signals;

 * Process, by the processing unit 17, the measurement signals provided by the measurement unit 11, the processing unit being configured to cancel the errors of the measurement signals;

 * Generate, by a generating unit 18, the one or more electrical stimulation signals of the patient's vestibular apparatus from at least the processed measurement signals carried by unit 1? of processing.

The conditioning stage of the described procedure would only be possible in those examples in which the device 12 comprises the conditioning unit.

In this way, this device 2 (that is, the different units that comprise it) to generate the one or more electrical stimulation signals described above can be used according to different configurations.

First, the device can be a computer system, understood as any set of interrelated parts (basically hardware and software) that allows

REPLACEMENT SHEET (RULE 26) storing and processing information, part of the hardware may include computers or any other type of intelligent electronic device, consisting of processors, memory, ate, suitable to be implanted in the patient. The software may include operating systems, firmware and applications.

More specifically, the device 12 for generating the one or more electrical stimulation signals may be a computer system comprising a memory and a processor, executable instructions for the processor being stored in the memory and these instructions comprising functionalities for executing the procedure for generating «Na or more electrical stimulation signals of the vestibular apparatus of a patient described above.

These instructions executable by the processor can form a computer program to cause e! computer system can execute the procedure described.

This computer program may be stored in physical storage media, such as recording media, computer memory, or read-only memory, or it may be carried by a carrier wave, such as electrical or optical. The computer program may be in the form of source code, object code or in an Intermediate code between source code and object code, such as in partially compiled form, or in any other form suitable for use in the implementation of the described procedure. The carrier medium can be any ntaritód or device capable of carrying the program.

For example, e! The carrier medium may comprise a storage medium, such as a ROM, for example a CD ROM or a semiconductor O, or a magnetic recording medium, for example an uro disk. In addition, the carrier means can be a transmissible carrier medium such as an electrical or optical signal that can be transmitted via electrical or optical cable or by radio or other means.

REPLACEMENT SHEET (RULE 26) When the computer program is contained in a signal that can be transmitted directly by means of a cable or other device or medium, the carrier medium may be constituted by said cable or other device or medium, alternate, the carrier medium may be an integrated circuit. that the computer program is capped (embedded), said integrated circuit being adapted to perform or for use in carrying out the described procedures.

It is important to note that each unit (the conditioning unit 18, the processing unit 17 and the generation unit 18) that makes up the device 12 can be a Computer system by itself, such as the design, or the same computer system can comprise several or all of the units.

On the other hand, each of these units 16,17,10 of the device 12 (or the whole of this device) can be connected by electronic means, computer means or a combination of both.

These means may be used interchangeably, that is, one part of the means for one unit (or for the entire device) may be electronic means and the other part may be computer means, or all means may be electronic means or all means. They can be computer means.

Examples of a device 12 comprising only electronic means {ie, a purely electronic configuration) can be a programmable electronic device such as a CPLD {Logic Devices Prog maÉi & s Complex ~ Compíex Progra mahiB Logic Dome), an FPGA (Programmable Door Matrix of C & mpo - Fi & í Programmable (£ & t®Á? y} or ASIC (Ckc itQ integrated by Apiicac ms Esp & ifiom - Appiiáafiofí-Specífi int & grat & Ci wiX suitable for implanting itself patient. Examples of a device 12 that only includes computer means, they can be the computer system described above.

Examples of a device 12 comprising a combination of computer media and electronic media may be a computer system such as ios described above in

 2. 3

REPLACEMENT SHEET (RULE 26) combination with electronic elements configured to execute those procedural steps for which they have been conceived (and are not executed by the computer system). Figure 8 shows a possible anatomical arrangement in the patient of! system 10 to stimulate the patient's vestibular apparatus by means of one or more electrical stimulation signals, the system of which can correspond to the system examples described in particular, this point is sufficient, in the figure the arrangement of the external device 50 can be seen, which comprises a source of supply and a coil, and of the implanfabte device 51. Forming from this device, a coil 52 can be seen, which inductively engages with the coil (not shown) of the external device 50 for feeding the electronics of the implantadle device 51, as well as for the exchange of data between both devices; a housing 53 in which the different sensor elements (accelerometers, gyroscopes - and / or magnetrometers) and the device 12 are housed to generate one or more electrical stimulation signals of the patient's vestibular apparatus from the measurement signals obtained by the sensor elements; a cable 54 connecting the device 12 to generate one or more electrical stimulation signals with the electrode plate 40 (application unit 3) in which the plurality of metal electrodes 42 configured to effect the electrical stimulations of the macula are housed (utricle and saccule) of the vestibular nerve; and a reference electrode 55.

Although only some particular embodiments and examples of the invention have been described herein, the person skilled in the art will understand that other alternative embodiments and / or uses of the invention are possible, as well as obvious modifications and equivalent elements. In addition, the present invention encompasses all possible combinations of the specific embodiments that have been described _^ The numerical signs relating to the drawings and placed in parentheses in a claim are only intended to increase the understanding of the claim, and should not be interpreted as limiting the scope of protection of the claim. The scope of the present invention should not be limited to specific embodiments, but should only be determined by an appropriate reading of the appended claims.

REPLACEMENT SHEET (RULE 26)

Claims

 RE! VIMDICACIOMES

1. Device (12) for generating one or more electrical stimulation signals of a patient's vesicle apparatus, characterized by the fact that the device comprises:

* A unit {17) processing measuring signals provided by a unit (1 1) ^'as comprising at least ios following sensing elements:

 - Three accelerometers (1 a) to provide acceleration measurement signals, ~ Three gyroscopes (14b) to provide angular velocity measurement signals,

 the processing unit being configured to cancel the errors of the measurement servants;

 * A unit (18) for generating the one or more electrical stimulation signals of the patient's vestibular apparatus, from at least the measurement signals processed by the processing unit (1?).

2. Device according to claim 1, comprising;

 * A conditioning unit of the measurement signals provided by the measurement unit (11), is this conditioning unit configured to reduce the noise of these measurement signals before it is? processed by the processing unit (17),

3. Device according to claim 2, wherein the conditioning unit (16) comprises;

 »One or more filter elements (20a) of the acceleration measurement signals provided by the accelerometers (14a) comprised in the measurement unit (1 1);

 - One or more elements {20b) for filtering the angular velocity measurement signals provided by the gyroscopes (1 faith) included in the measuring unit (11).

4. Device according to claim 3 _> wherein at least one of the filter elements (20a, 20.b) comprises at least one filter that is selected from the following;

 o Medium filter;

 o Media filter;

REPLACEMENT SHEET (RULE 26) o Adaptive filter;

 o Maximum or minimum filter.

5. Device according to any one of claims 1 to 4 »wherein the unit (1β) for generating the signal of electrical isolation of the patient's vestibular apparatus is configured to generate the signal and electrical stimulation from:

 - The measurement signals processed by the processing unit {17};

 - Patient characteristics.

6. Device according to claim 5 _» and the one which the patient's characteristics select from and will go:

_* Maximum stimulation current that the patient is able to withstand;

 - Minimum stimulation current with which the patient is able to perceive the stimulus;

 - Maximum range of stimulation frequencies;

 Minimum range of stimulation frequencies.

Device according to any one of claims 1 to 6, in the c:: oe the processing unit {17} comprises an element configured to apply a Raiman filter {21} on the measurement signals, so that the Processed measurement signals comprise the measurement signals of pitch (22), warping (23) and yaw (24).

A device according to any one of claims 1 to 7, wherein the measurement unit {11} further comprises as three magne ro e eiros sensor elements (14c) to provide signals of measurement of the intensity of the magnetic fields on each axis ,

9. Device according to claim 8, wherein the unit (16) for conditioning the measurement signal further comprises;

 - One or more elements {20c} for filtering the measurement signals of the intensity of the magnetic fields on each axis provided by the magnetrometers (14c) included in the measuring unit (11).

REPLACEMENT SHEET (RULE 26)

0. Device according to claim Q, m e! that at least one of the elements (20c) for filtering the measurement signals of the intensity of the magnetic fields on each axis comprises at least one filter that is selected from the following:

 o Medium filter;

 o Media filter;

 o Adaptive filter;

 o Maximum or minimum filter.

11. Device according to any one of claims 1 to 10, wherein an electrical signal from the patient's vestibular apparatus generated by the generating unit (! Ø} comprises an ultimate electrical pulse (SO), which comprises two or more electrical pulses {31} of alternating polarity, with variable amplitude (34) and pulse width {35}, for a period of time (32) of duration of the electrical pulse (30) and time spacing (33) between electrical impulses (31),

12. Device according to claim 11, wherein the amplitude (34) of stimulation of each electrical impulse (3) depends at least d the characteristics of the patient relative to the maximum stimulation current that the patient is able to withstand and the current of minimal stimulation with the patient the patient is able to perceive the stimulus,

13. Device according to claim 12, in which the amplitude (34) of each pulse is obtained from the formula:

where A «& represents the maximum stimulation current that the patient is able to bear, U» * represents the minimum stimulation current with which the patient is able to perceive the stimulus and SL represents the level of stimulation at which Stimulation is going to be done.

14. Device according to any one of claims 11 to 13, wherein the period of time (32) of duration of the electric pulse {30} depends at least on the characteristics of the patient relative to the maximum range of stimulation frequency and the range minimum stimulation frequencies.

 ? 7

REPLACEMENT SHEET (RULE 26) 1S. Device according to claim 14, in the EU the period of time (32) of duration of the electric tapping (30) is obtained from the formula:

where Fm & * represents the maximum range of stimulation frequencies, Fm * represents the minimum range of stimulation frequencies and β is a normalized acceleration factor that depends on the processed measurement signals.

16. Device according to claim 14, wherein the period of time (32) of duration of the electrical pulse (30) is obtained from the formulas:

where F _m3X represents e! maximum range of stimulation frequencies, ¥ _m m represents the minimum range of stimulation frequencies, β is a normalized acceleration factor that depends on the processed measurement signals and C represents the curvature of this function.

one?. Device (12) for generating one or more electrical stimulation signals of a patient's vestibular apparatus, characterized by the fact that the device is configured to:

* Process _* by a unit (1?) D pm processing, measurement signals provided by a unit (1) of measurement comprising at least the following sensor elements:

 Three aceieromers (14a) to provide acceleration measurement signals, - Three gyroscopes (14b) to provide angular velocity measurement signals,

 the processing unit being configured to cancel the errors of the measurement signals;

REPLACEMENT SHEET (RULE 26) * Generate, by a generation unit (18), the one or more electrical stimulation signals of the patient's vestibular apparatus from at least the measurement serials processed by the processing unit (17).

18, Device according to claim 17, which is configured to:

* Conditioning, by a conditioning unit (18) _* the measurement signals provided by the measurement unit (11), this conditioning unit being configured to reduce the noise of these measurement signals before being processed by the unit (17) processing,

19, A method for generating one or more electrical stimulation signals from the vestibular system of a patient, caracterizad © ^'by the fact that the method comprises:

 * Process, by a unit (17). processing, measurement signals provided by a measurement unit (11} comprising at least the following sensor elements:

 - Three accelerometers (14a) to provide acceleration measurement signals,

- Three gyroscopes (14b) to provide angular velocity measurement signals,

 the processing unit p being configured to cancel the errors of the measurement signals;

 * {Benefit, by a generation unit (18), the one or more electrical stimulation signals of the patient's vestibular apparatus from at least the measurement signals processed by the processing unit (1?).

20, Method according to claim 10, comprising:

 * Conditioning, by a conditioning unit (18), the measurement signals provided by the measurement unit (11}, this conditioning unit being configured to reduce the noise of these measurement signals before being processed by the unit (17) processing.

^• 21. Computer program comprising computer instructions to cause a computer system to execute a method according to any one of claims 19 or 20 to generate one or more electrical stimulation signals from a patient's vestibular apparatus.

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REPLACEMENT SHEET (RULE 26)

22. Computer program according to claim 21, stored in storage media, 23. Computer program according to any one of claims 21 or 22, carried by a carrier signal,

24, Computer system comprising a memory and a processor, the memory being stored executable instructions by the processor and these instructions comprising functionalities for executing a method according to any one of claims 19 or 20 to generate one or more electrical stimulation signals of the apparatus vestibular of a patient.

25. System (10) for stimulating the vestibular apparatus of a paoionte by one or more electrical stimulation signals, the system comprising an Impiantaole device comprising;

 »A unit of measure (11} comprising at least the following sensor elements;

 - Three aeeierd-mettos (14a) to provide acceleration measurement signals; - Three gyros i4b) to provide angular velocity measurement signals;

 * A device {2} for generating one or more electrical stimulation signals of a patient's vestibular system according to any one of claims 1 to 18, from the measurement signals provided by the measuring unit (11);

 * A unit (13) for applying the electrical stimulation signals generated on the patient's vestibular apparatus.

28. System according to claim 19, wherein the measuring unit (11) further comprises as sensor elements three magnetrometers {14c} to provide signals measuring the intensity of the magnetic fields on each axis,

2?. System according to any one of claims 25 or 26, wherein the application unit (13) comprises an electrode plate (40).

30

REPLACEMENT SHEET (RULE 26) 28, If subject according to claim 27, therein the electrode plate {40} comprises a plurality of electrode (42}, such as between 7 and 12 electrodes,

29, System according to any one of claims 27 or 26, wherein the 5 electrode plate {40} is configured to have at least one electrode in the region fe! Saculo and a! least one electrode in the utricule region of the vestibula apparatus of! patient,

30, System according to any one of claims 28 or 2¾ wherein the plurality of electrodes {42} comprises an electrode configured to record the voltage 0 produced by the vestibular nerve once the electrical stimulation is applied.

3, System according to any one of claims 25 to 30, in which the application unit {13} comprises a reference electrode, S 32. System according to claim 31, wherein the reference electrode is configured to be arranged in the patient's mastoid.

33. System according to any one of claims 26 to 33, wherein the im lantabie device comprises an element for the transmission and / or reception of energy.

0

 34. A system according to claim 33, wherein the element for transmitting and / or receiving energy from the impiantable device comprises a first coil,

35. A system according to any one of claims 25 to 34, m wherein the imptafttable device6 comprises an emenopho for data transmission and / or reception,

3i, System according to claim 36, wherein the element for the transmission and / or reception of data from the impiantable device comprises a second coil, or 3. System according to any one of claims 25 to 38, comprising an external device to the patient comprising:

 * A power supply;

 * One element for the transmission and / or reception of energy, connect to the power supply.

 31

REPLACEMENT SHEET (RULE 26)

38. System according to claim 3, wherein the element for the transmission and / or reception of energy of the external device comprises a third coil,

39. Sssterna Segur? claim 38 when claim 3? it depends on claims 34 to 36, wherein the first coil of the implandable device and the third coil of the external device are configured to establish an inductive coupling.

40. System according to any one of claims 37 39, wherein the external device comprises an element for the transmission and / or reception of data.

41. System according to claim 40, wherein the element for transmitting and / or receiving data from the external device comprises a fourth coil,

42. System according to claim 41 when claim 37 depends on claim 36, wherein the second coil of the Impiantabie device and the fourth coil of the external device are configured to establish an inductive coupling.

32

REPLACEMENT SHEET (RULE 26)