Patent Application
20230414133
The present application relates to an acoustic measurement device configured to provide acoustic property values for objective ear-condition evaluation of a patient's ear, wherein at least part of the acoustic measurement device being configured to be positioned within an ear canal of the patient and configured to take a resting position within the ear canal. The acoustic measurement device comprises an ear probe and the acoustic measurement device comprises an air-pump arrangement. The air-pump arrangement, at least in the resting position, being in fluid connection with the ear canal through at least one tube running via the ear probe. The air-pump arrangement, in the resting position, is configured to apply an air-pressure control procedure, consisting of at least one air-pressure level, across the patient's tympanic membrane of the ear, wherein the acoustic measurement device, in the resting position, being configured to provide acoustic property values in reaction to the air-pressure control procedure applied by the pump arrangement across the patient's tympanic membrane of the ear.
The application further relates to a diagnostic instrumental arrangement configured to provide at least one objective ear-condition parameter of a patient's ear comprising an acoustic measurement device according to the application, further comprising an acoustic input unit configured to capture acoustic signals representative for the air-pressure levels within the ear canal, a control device configured to control the pump arrangement, and a processing device configured to further process the captured acoustic signals to an evaluation device, the evaluation device being configured to execute an evaluation process to the processed acoustic signals associated to the air-pressure control procedure to obtain the at least one objective ear-condition parameter for the patient's ear.
Moreover, the present application relates to an objective ear-condition evaluation method using a diagnostic instrumental arrangement according to the application.
Acoustic measurement devices and diagnostic instrumental arrangements are known in the art for example from tympanometric diagnostic methods, diagnostic methods for pressurized acoustic-reflex measurement, or diagnostic methods for otoacoustic-emission measurement. Those instruments known in the art for hearing diagnostics conventionally utilize piston, peristaltic, or gear pumps. These pumps are characterized by being driven by an electric motor, and operating the motor at some constant power generates a constant volume-displacement rate.
These pumps offer suitable performance when it comes to perform air-pressure control procedures as they are for example standardized for several diagnostic type instruments in IEC 60645-5 (2005), thereby operating—even in the case of tympanometry—within a rather small pressure-difference region (with magnitudes up to 600 daPa) relative to the absolute ambient pressure (approximately 10132.5 daPa), resulting in an approximately constant-rate pressure sweep usually requiring no or little regulation.
However, these pumps have several less-desirable properties such as their mechanical complexity, their large size, and their relatively slow responsiveness due to the internal mass which needs to move before the pressure changes. In particular, as regards the application of a piston pump, the respective acoustic measurement device then further suffers from its inherent displacement limits.
Therefore, there is a need to provide a solution that addresses at least some of the above-mentioned challenges that come along with the known acoustic measurement devices and their air-pump arrangement.
Thus, it is the object of the present application to provide an acoustic measurement device and a diagnostic instrumental arrangement as described above, which do not show the disadvantages described above, or at least show them to a lesser extent, and which, in particular, provide a space saving design for an acoustic measurement device, which reduces the overall effort, e.g. in terms of handling the acoustic measurement device and instrumental arrangement during diagnostics, and facilitates simple production of such device, however at the same time providing reliable results for the objective ear-condition evaluation of the patient's ear.
The above objects are achieved starting from an acoustic measurement device according to the preamble of claim 1 by the features of the characterizing part of claim 1. The above objects are further achieved by the diagnostic instrumental arrangement according to claim 14 and are also achieved by an objective ear-condition evaluation method according to claim 16.
The present application is based on the technical teaching that a more space saving design results, for example, in a more handy operation of the respective instrument. Further, reliable results for objective ear-condition evaluation can be accomplished, if instead of the known pump configurations applied in the field of objective acoustic measurements so far (e.g. piston, peristaltic, or gear pumps), a membrane pump (also known as a diaphragm pump) configuration is used. The membrane pump configuration may (preferably) be formed as a piezo-electric membrane pump configuration (e.g. a miniature piezo-electric membrane pump configuration).
This alternative type of pump, namely a membrane pump and in particular in the form of a miniature piezo-electric membrane pump, generally operates by displacing an elastic element, in particular a membrane, in a harmonic motion.
Usually, in its regular field of application, this pump then relies on internal check valves (i.e., allowing flow in one but not the other direction) to turn this oscillating displacement into an air flow, which enters through an inlet during the first half cycle and exits through the outlet in the second half cycle. Thus, these kind of membrane pumps are known to be inherently unidirectional, a directionality which is defined by the orientation of the check valves.
Hence, according to one aspect, the present application relates to an acoustic measurement device configured to provide acoustic property values for objective ear-condition evaluation of a patient's ear, in particular a human's ear, wherein at least part of said acoustic measurement device being configured to be positioned within an ear canal of said patient and configured to take a resting position within said ear canal, said acoustic measurement device comprising an ear probe, said acoustic measurement device comprising an air-pump arrangement, said air-pump arrangement, at least in said resting position, being in fluid connection with said ear canal through at least one tube running via said ear probe, said air-pump arrangement, in said resting position, being configured to apply an air-pressure control procedure, consisting of at least one air-pressure level, across said patient's tympanic membrane of said ear, wherein said acoustic measurement device, in said resting position, being configured to provide acoustic property values in reaction to said air pressure control procedure applied by said pump arrangement across said patient's tympanic membrane of said ear.
Said air-pump arrangement comprising at least two pumps, wherein said at least two pumps comprising a movable element in the form of a membrane.
For example, the provided acoustic property values comprise values representative for acoustic impedance against said patient's tympanic membrane of said ear.
For example, the provided acoustic property values comprise values representative for acoustic admittance against said patient's tympanic membrane of said ear.
For example, the provided acoustic property values comprise values representative for absorbance.
Then, the acoustic measurement device may act as a tympanometer and a tympanogram can be obtained.
For example, the provided acoustic property values comprise values representative for otoacoustic emission.
The acoustic measurement device according to the application is especially suitable for providing acoustic property values for objective ear-condition evaluation for human's ears, but the application is not limited thereto. The concept of the device and the instrument according to the application could be applied for objective ear-condition evaluation of animals as well.
Basically, the membrane of each of the pumps of the pump arrangement can be formed in any suitable way. Very beneficial configurations can be achieved in terms of compactness and size-reduction of the pump arrangement if the at least two pumps are configured to act as membrane pumps for applying the air-pressure control procedure and particularly if they are formed as membrane pumps. Their miniature size allows an easier handling of the device and consequently an easier handling of the entire instrument according to the application.
In preferred variants of the application, the acoustic measurement device further comprises an acoustic input unit that is configured to capture acoustic signals representative for the air-pressure levels within the ear canal. The acoustic measurement device may comprise a control device that is configured to control the air pump arrangement. For example, the control device may comprise any form of regulation algorithm/controller to control the air-pump arrangement. For example, the control device may comprise a proportional—integral—derivative (PID) controller to control the air-pump arrangement, in particular using a regulation algorithm to perform for example constant pressure-sweep rates. This is particularly beneficial when the acoustic measurement device is used in tympanometry. The regulation algorithm may be based on an air pressure measured by a pressure sensor close to the acoustic input unit. The acoustic measurement device may further comprise a processing device that is configured to further process the captured acoustic signals.
In further preferred variants of the applications, the at least two pumps are formed as piezo-electric membrane pumps. The piezo-electric membrane pumps may then each be arranged fluidically in series with at least one flow-regulating component, wherein they are acting fluidically in parallel. Therein, each of the flow regulating components may be configured and arranged within the air pump arrangement such that at least one piezo-electric membrane pump is capable of working bidirectional when applying the air-pressure control procedure.
Therein, in very beneficial variants of the application, it is provided that the at least two pumps comprise a first pump and a second pump, where the first pump and the second pump being poled in opposing directions to each other.
So, in other words, the air pump arrangement may be configured such that the at least two pumps, preferably being (miniature) piezo-electric membrane pumps, are capable of working simultaneously to control the air pressure level within the air pressure control procedure in the ear canal.
The flow regulating components in the above-described configurations may be formed as flow resistors.
In some preferred variants of the application, an air pump arrangement provides a first piezo-electric membrane pump fluidically in series with a first flow resistor and a second piezo-electric membrane pump fluidically in series with a second flow resistor. The air pump arrangement may be configured and arranged such that pressure between the first flow resistor and said second flow resistor can be controlled in the ear-canal of the respective ear. Thereby, the air pump arrangement may essentially act in the manner analogous to a voltage divider, by maintaining and adjusting an inlet pressure and an outlet pressure at the first and the second piezo-electric membrane pump.
Further preferred variants of the application comprise an acoustic muffler that is provided and arranged at the ear probe. For example, the acoustic muffler may attenuate acoustic noise generated by the air-pump arrangement from entering the ear canal and interfering with ongoing acoustic measurement. The acoustic muffler may be configured to constitute the flow regulating components described above, preferably in the form of a flow resistor. For example, the acoustic muffler may consist of a network of narrow tubes and cavities, configured to attenuate acoustic noise and acting in a manner of a flow resistor.
In certain preferred variants of the application, (for example, when the acoustic measurement device is used for tympanometry, and hence acts in the form of a tympanometer), its air pump arrangement, in the resting position within the patient's ear, is configured to apply the air pressure control procedure in the form of maintaining essentially a single air pressure level during the procedure. Conventionally, the air pressure level lies in the range of −600 to +400 daPa.
In addition, or as an alternative, the air pump arrangement, in the resting position, may be configured to apply the air pressure control procedure in the form of performing varying air pressure levels during the respective procedure with varying air pressure levels during the procedure ranging between around −600 daPa to +400 daPa. In such a case, preferably, the respective procedure follows the standardized procedure of varying air pressure for different instrumental types according to IEC 60645-5 (2005). For example, the air pump arrangement, in the resting position, may be configured to perform these varying air-pressure levels with an adjustable air-pressure sweep rate. Thereby, a tympanogram can be obtained in a reliable manner but with a more handy and compact acoustic measurement device thanks to the use of membrane pumps, in particular in the form of miniature piezo-electric membrane pumps.
The acoustic measurement device may be configured to provide acoustic property values representative for the patient's middle-ear in reaction to a first pressure control procedure of the air pressure control procedure, applied by the at least two pumps of said air pump arrangement across the patient's tympanic membrane of the ear.
The first pressure control procedure may contain performing varying air pressure levels during the procedure ranging between around −600 daPa to +400 daPa. Therein, the provided acoustic property values may be values representative for acoustic impedance against the patient's tympanic membrane of the respective ear to be diagnosed. In such a configuration for tympanometry, the air pump arrangement, in the resting position, may be configured to perform the varying air-pressure levels with an adjustable air pressure sweep rate. Preferably, also here, the air pump arrangement is capable of performing the air pressure sweep rates following the standardized procedure according to IEC 60645-5 (2005).
In addition, or as an alternative, the acoustic measurement device may be configured to provide acoustic property values representative for the patient's inner ear in reaction to a second pressure-control procedure of the air-pressure control procedure, applied by the at least two pumps of the pump arrangement across the patient's tympanic membrane of the ear.
The second pressure control procedure may contain performing and maintaining essentially a single air-pressure level during the procedure. The essentially single air pressure level performed may lie in the range of −600 to +400 daPa. The acoustic measurement device may be configured to act as a hearing diagnostic instrument for pressurized acoustic-reflex measurement.
In addition, or as an alternative, the acoustic measurement device may be configured to provide acoustic property values representative for the patient's inner-ear in reaction to a third pressure control procedure of the air-pressure control procedure, applied by the at least two pumps of the pump arrangement across the patient's tympanic membrane of the ear.
The third pressure control procedure may contain performing and maintaining essentially a single air pressure level during the procedure. The essentially single air pressure level performed may lie in the range of −600 to +400 daPa. The acoustic measurement device may be configured to act as hearing diagnostic instrument for otoacoustic-emission measurement.
According to a further aspect, the present application relates to a diagnostic instrumental arrangement that is configured to provide at least one objective ear-condition parameter of a patient's ear, in particular of a human's ear. The diagnostic instrumental arrangement comprises an acoustic measurement device according to any of the configurations or variants according to the application as described above. Furthermore, an acoustic input unit is provided and configured to capture acoustic signals representative for the air-pressure levels within the ear canal. Further, a control device is provided that is configured to control the pump arrangement according to any of the configurations or variants according to the application as described above. Finally, the diagnostic instrumental arrangement comprises a processing device configured to further process the captured acoustic signals to an evaluation device, the evaluation device being configured to execute an evaluation process to the processed acoustic signals associated to the air-pressure control procedure to obtain the at least one objective ear-condition parameter the said patient's ear.
The diagnostic instrumental arrangement may be is mechanically connectable to a stand-alone device and/or may be operated via a mobile end device, in particular a tablet or a smartphone.
According to a further aspect, the present application relates to an objective ear-condition evaluation method which uses a diagnostic instrumental arrangement as described above with an acoustic measurement device according to any one of the configurations or variants of the application as described above.
It is contemplated that the acoustic measurement device may comprise said air-pump arrangement, which comprises at least one pump (such as only one pump), wherein said at least one pump comprising a movable element in the form of a membrane. Further, said air-pump arrangement may comprise at least one flow regulating component, such as one or two flow regulating components.
Further preferred variants of the present application will become apparent from the dependent claims and the following description of a preferred embodiment of the acoustic measurement device and instrument arrangement which refers to the appended figures.
In the following, an example of an acoustic measurement device 1 is shown and described, which comprises an exemplary air pump arrangement 2 according to the application. The air pump arrangement 2 may comprise a first and a second pump. The first and/or the second pump may be a membrane pump. For example, the first and/or the second pump may be a piezo-electric membrane pump. For example, the first and/or the second pump may be a miniature piezo-electric membrane pump. The acoustic measurement device 1 may be used in a diagnostic instrumental arrangement (not further shown here).
In
Further, in
The ear probe 7 may comprise an ear tip 8, which may be releasably attached to an ear-probe body 9. When the ear probe 7 has been inserted into the ear canal 5 (and take a resting position), the ear tip 8 may provide a barometric seal toward the ear-canal walls 10 of the ear canal 5. The ear probe 7 may provide a stimulus into the ear of the patient 6 in a direction towards the eardrum 11 and receive a reflected part of said stimulus (i.e. capture acoustic signals), as indicated by the two arrows located in the ear canal 5.
The acoustic measurement device 1 may further comprise a control device 12 configured to control said pump arrangement 2.
The acoustic measurement device 1 may further comprise a processing device 13 configured to process said captured acoustic signals. An evaluation device of said processing device 13 may be configured to execute an evaluation process to said processed acoustic signals associated to an air-pressure control procedure to obtain at least one objective ear-condition parameter for said patient's 6 ear.
Preferably, the acoustic measurement device 1 is used for tympanometry, hence acts in the form of a tympanometer. However, in addition, the acoustic measurement device 1 may also be configured to perform diagnostic methods for pressurized acoustic-reflex measurement or diagnostic methods for otoacoustic-emission measurement.
The air pump arrangement 2 may be configured to apply an air pressure control procedure in the form of maintaining essentially a single air pressure level during the procedure. For example, the air pressure level then lies in the range of −600 to +400 daPa.
In addition, the air pump arrangement 2 may be configured to apply the air pressure control procedure in the form of performing varying air pressure levels during the respective procedure with varying air pressure levels during the procedure in the range of around −600 daPa to +400 daPa. The air pump arrangement 2 may be capable of performing the standardized procedures of varying air pressure for different instrumental types according to IEC 60645-5 (2005), which will be described by way of an example in the context with
In
Unlike a regular membrane-pump arrangement where two membrane pumps, each one being fluidically in series with one check valve, never operate simultaneously, the air pump arrangement 2, as given in
While this configuration of air-pump arrangement 2 restricts the total flow through the system (compared to the case of no flow resistors), it allows accurately controlling the pressure between the two flow resistors 4a, 4b, i.e., in the ear canal, in a manner analogous to a voltage divider, by maintaining and adjusting the pressure at the outlet and inlet of the membrane pumps 3a and 3b, respectively and, thus, the flow through the resistors 4a, 4b. That is, maintaining a constant air pressure in the ear canal requires continuous operation of one membrane pump (3a or 3b).
This is opposed to the prior art pumps used in acoustic measurement devices, as piston pumps, peristaltic pumps, and gear pumps, where maintaining a constant ear-canal pressure simply requires stopping the pump.
In particular, the air pump arrangement 2 solves the issue associated with regular membrane pumps of not being able to control the flow through the membrane pump 3a, 3b due to a negative pressure drop in the flow direction because the pressure drops in the system occur across the two flow resistors 4a, 4b. That is, each membrane pump 3a, 3b can generate a change in pressure between the membrane pump 3a, 3b and flow resistor 4a, 4b, regardless of the pressure in the ear canal, and force a larger flow through the resistor than dictated by the ear-canal-to-ambient pressure difference.
Depending on the flow resistances R1 (associated with flow resistor 4a) and R2 (associated with flow resistor 4b), operating membrane pumps 3a and 3b at some constant power results in a given point of operation on the pressure-flow relationship in
Thus, manipulating P1 and P2 by controlling the drive power to each membrane pump 3a, 3b any pressure can be achieved in the ear canal Pee and this pressure can be altered in any direction.
Deriving the pump drive powers that yield a constant-rate ear-canal pressure Pec(t) is more complicated because the pressure-flow operational point of each pump changes temporarily in response to sudden changes in power until a steady state has been reattained. Assuming that the pressure-flow operational point remains constant and that a change in pump powers result in proportional changes in P1(t) or P2(t), the ear-canal pressure response Pec(t) resulting from step changes in pump drive powers takes the form of an exponential decay,
P
ec(t)=αe−bt+c.
The constants a, b, and c are mathematical expressions comprised by R1, R2, the compliance of the ear canal Cec (which is inversely proportional to its volume), and the initial and final values of the pressure step functions P1(t) and P2(t). Consequently, the pressures P1(t) or P2(t) required to produce linear changes to the ear-canal pressure Pec(t) when operating only one membrane pump 3a or 3b at a time can be immediately calculated.
While it is possible to predict how the membrane pumps 3a, 3b should be driven to achieve ear-canal pressure with constant pressure sweep rates with the given approximations and a given ear-canal volume, practical application in ear-canals of varying volumes require a regulation algorithm. In such a case, for example, a PID controller is used to achieve these constant pressure-sweep rates. For example, this regulation algorithm is based on the air pressure measured by a pressure sensor close to the ear probe.
Accordingly, the acoustic measurement device may comprise a pressure sensor.
A standard air-pressure procedure required to generate a tympanogram may usually consists of three principal steps.
First, the air pump arrangement is used to pump to a desired starting pressure. In terms of the pressure difference across the tympanic membrane, this starting pressure may be within at least the range of −600 to +200 daPa for type-1 instruments and −200 to +200 daPa for type-2 and type-3 instruments (IEC 60645-5 (2005)), although instruments often support wider pressure ranges, e.g., −600 to +400 daPa (see
The second step involves a pressure sweep, specified by a constant pressure sweep rate in units of daPa/s (positive or negative depending on the direction of the sweep), from the starting pressure to the stopping pressure of opposite operational sign. Type-1 instruments must be capable of maintaining a constant sweep rate of 50 daPa/s with a tolerance of ±10 daPa/s for the duration of the sweep (IEC 60645-5 (2005)), passing the 0-daPa pressure-difference point. The acoustic measurements of the middle ear may be acquired during this pressure sweep of the second step.
Finally, as the third step, the ear-canal pressure is returned to ambient pressure in a controlled manner to minimize patient discomfort, concluding the pressurization procedure.
Other air-pressure procedures used in tympanometry may include a manual tympanogram, where the operator adjusts the pressure in the ear canal using, e.g., a slider, while observing the acoustic changes to the middle ear.
The sequence shown in
It is intended that the structural features of the devices, arrangements and instruments described above, either in the detailed description and/or in the claims, may also account for the corresponding process as it is claimed by the objective ear-condition evaluation method using such devices, arrangements and instruments.
The particular features, structures or characteristics may be combined as suitable in one or more embodiments of the disclosure. The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects, variants and configurations will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects.
Accordingly, the scope should be judged in terms of the claims that follow.
| Number | Date | Country | Kind |
|---|---|---|---|
| 22180714.2 | Jun 2022 | EP | regional |
