WO2022002773A1

WO2022002773A1 - Otoscope

Info

Publication number: WO2022002773A1
Application number: PCT/EP2021/067455
Authority: WO
Inventors: Thomas Bischof
Original assignee: Helmholtz Zentrum München Deutsches Forschungszentrum Für Gesundheit Und Umwelt (Gmbh)
Priority date: 2020-07-01
Filing date: 2021-06-25
Publication date: 2022-01-06

Abstract

The invention relates to an otoscope (100), comprising a light source (108) configured to emit light to illuminate an ear canal, visualization means (106) configured to display the ear canal illuminated by the light emitted by the light source (108) for visual inspection of the ear canal by a user, a spectral sensor (110) configured to measure intensities of the light emitted by the light source (108) and reflected by the ear canal, the spectral sensor (110) being configured to measure at least a first intensity in a first spectral range and a second intensity in a second spectral range, and a controller (112) configured to calculate a parameter on the basis of the first intensity and the second intensity.

Description

Otoscope

Technical field

The invention relates to an otoscope.

Technical background

An otoscope is a device used by clinicians to inspect the ears of patients. A common purpose of such an examination is to determine whether fluid is present behind the eardrum, which is an indication of an infection or injury.

Summary of the invention

An object of the invention may be seen in improving diagnosis of a disease state of the ear canal and/or tympanic membrane. A further object of the invention may be seen in improving the measurement of an amount of water in the ear canal. A further object may be seen in simplifying diagnosis of a disease state of the ear canal and/or tympanic membrane and/or the measurement of an amount of water in the ear canal. A further object may be seen in providing an integrated device for visual inspection of the ear canal and providing an objective diagnosis of a disease state of the ear canal and/or tympanic membrane and/or measure an amount of water in the ear canal. Moreover, further objects may be seen in reducing costs, improving usability and/or reliability of such a device.

This object and further objects are solved by the subject-matter of the independent claims. Further preferred features are specified in the dependent claims, the description and the drawings.

An embodiment of the invention relates to an otoscope, comprising a light source configured to emit light to illuminate an ear canal, visualization means configured to display the ear canal illuminated by the light emitted by the light source for visual inspection of the ear canal by a user, a spectral sensor configured to measure intensities of the light emitted by the light source and reflected by the ear canal, the spectral sensor being configured to measure at least a first intensity in a first spectral range and a second intensity in a second spectral range, and a controller configured to calculate a parameter on the basis of the first intensity and the second intensity.

The term “otoscope” may be understood to relate to a medical device that is adapted to be used to visually inspect the ear canal and/or the tympanic membrane. For sake of simplicity and conciseness, this document merely refers to the ear canal. However, this shall also include, e.g., that the tympanic membrane is illuminated and visualized. In order to visually inspect the ear canal, the otoscope comprises the light source to illuminate the ear canal and visualization means configured to display the ear canal. That is, the light emitted by the light source and reflected by the ear canal is displayed by the visualization means.

Thus, the otoscope is configured to guide the light in such a way that it illuminates the ear canal in use. For example, the light source may be arranged and oriented such that it directly illuminates the ear canal. Alternatively, the otoscope may comprise a light guide or light guides to direct the light from the light source into the ear canal to illuminate the ear canal.

The light source may be located on, e.g. mechanically attached to, or functionally connected to a printed circuit board, in particular when the otoscope comprises a light guide or light guides to direct the light into the ear canal.

The visualization means may be analogue, i.e. comprising optics, e.g. a magnifying lens or lens system, and/or digital, i.e. comprising a digital image sensor, e.g. a CCD sensor, and a display for displaying an image sensed by the digital image sensor, such as a digital view finder of a digital camera. Moreover, the visualization means may be a hybrid system comprising optics and digital visualization means.

The spectral sensor may refer to a single sensor configured to measure the first intensity and the second intensity or to a set of sensors comprising at least a first sensor configured to measure the first intensity and a second sensor configured to measure the second intensity. The spectral sensor may also comprise read-out electronics. For example, the spectral sensor may be provided on a printed circuit board that comprises the read-out electronics. Alternatively, the read-out electronics may be a part of the controller. In the following, the measurement of the first and second intensity may also be referred to as “spectral measurement”.

The spectral sensor is configured to measure the first intensity and the second intensity based on the light emitted by the light source and reflected by the ear canal. Moreover, the light emitted by the light source and reflected by the ear canal is also used for the visual inspection of the ear canal. Thus, the same light and light source is used for visual inspection and for measuring the first and second intensity.

Therefore, it is not necessary to provide an additional light source for the spectral measurement. In this way, the costs of the otoscope may be reduced. Furthermore, there are less components to be integrated into the otoscope, such that the form factor of the otoscope may be improved. Moreover, as it is not necessary to control two light sources, usability of the otoscope may be improved and/or the otoscope may be more reliable.

The controller is configured to receive and process the first intensity and the second intensity. Furthermore, the controller is configured to calculate a parameter on the basis of the first intensity and the second intensity. The term “parameter” may also include more than one parameters. The parameter may comprise a physical quantity and/or an index. The parameter, e.g. the physical quantity and/or index, may relate to a physical condition of the ear. Moreover, the controller may be configured to send the parameter or an associated condition to the visualization means and/or to instruct the visualization means to display the parameter or associated condition.

The controller may be provided separately from and in addition to the spectral sensor. Alternatively, the controller and the spectral sensor may be provided as one integrated component, e.g. on the same printed circuit board.

By calculating a parameter as described above, diagnosis of a disease of the ear is improved and/or an objective diagnosis is provided.

Preferably, the parameter relates to an amount of water behind the ear drum. In this way, the otoscope is configured to measure whether there is and/or an amount of fluid behind the tympanic membrane, which may be an indication of an infection and/or injury of the ear. In this way, an objective diagnosis of a disease of the ear is provided.

The parameter may relate to the absorbance of water. For example, the parameter comprises a reflectance or absorbance of light by water, such as the amount of the reflected spectrum of light which can be assigned to water or another material of interest.

Preferably, the light emitted by the light source has a spectral range spanning over at least 1400 nm to 1500 nm, preferably 600 nm to 1700 nm, more preferably 400 nm to 1700 nm. In other words, the light source may be a broadband light source.

Thus, preferably, the light emitted by the light source comprises a fraction of visible light for visual inspection and a fraction of infrared light (preferably around 1470 nm) that is absorbed by water. This is based on the understanding that water exhibits an absorbance spectrum of infrared light, primarily at 1470 nm, which is distinct from other materials found in the ear. Fluid present in the ear is partially composed of water. Thus, fluid in the ear may be objectively diagnosed by measuring an absorbance of light, e.g., around 1470 nm.

The light range between 1400 nm and 1500 nm may be primarily used for water detection. The light range between 400 nm and 1700 nm includes visible light, which may be used for visual inspection as well as for water detection.

Moreover, by using a broadband light source, the absorbance/reflectance of the light emitted by the light source in different spectral ranges may be determined. In this way, disturbing influences, e.g. background light, may be determined more precisely, such that the absorbance of light by water may be determined more precisely.

Preferably, the light source comprises a tungsten-filament light bulb, a number of light- emitting diodes, or some mixture thereof.

In this way, it may be ensured that the light source provides light that is suited for the visual inspection as well as for the spectral measurement. Preferably, the first spectral range is between 1400 nm and 1550 nm, preferably between 1450 nm and 1500 nm, more preferably around 1470 nm.

Preferably, the second spectral range is between 1200 nm and 1400 nm, more preferably between 1200 nm and 1350 nm, even more preferably around 1250 nm.

In this way, the absorbance of light by water may be effectively measured.

Preferably, the light source comprises at least a first light source and a second light source, the first light source being configured to emit visible light, the second light source being configured to emit light having a wavelength between 1200 nm and 1550 nm, more preferably between 1450 nm and 1500 nm, even more preferably around 1470 nm.

Visible light may be understood to include light with a wavelength between about 380 to 740 nm.

Preferably, the first light source is configured to emit white light.

Preferably, the spectral sensor comprises at least a first photodiode configured to measure the first intensity a second photodiode configured to measure the second intensity.

Photodiodes and related sensor technologies offer an advantage of simple device architecture allowing for board-level integration and portable design. In this way, a highly integrated otoscope may be provided.

Preferably, the first photodiode comprises a first band-pass filter and the second photodiode comprises a second band-pass filter.

The band-pass filters may, e.g., be provided in form of optical cavities, detector geometry, and/or coatings provided on the photodiodes.

In this way, the first photodetector has a spectral sensitivity distinct from that of the second photodiode. By using multiple photodetectors or photodiodes with different spectral sensitivities, it is possible to measure the first and second (and optionally further) intensities using the same light source. Thus, for example, a broad-band light source may be used for visual inspection and for spectral measurement.

Preferably, the first band-pass filter and/or the second band-pass filter has a full-width-half- maximum or band-width of 150 nm or less, preferably between 10 nm and 30 nm, more preferably, between 15 nm and 25 nm, even more preferably between 18 nm and 22 nm.

In other words, a first spectral band transmitted by the first band-pass filter and/or a second spectral band transmitted by the second band-pass filter and/or spectral bands of further band pass filters may have a full-width-half-maximum or a band-width of 150 nm or less, preferably between 10 nm and 30 nm, more preferably, between 15 nm and 25 nm, even more preferably between 18 nm and 22 nm.

Such band-widths may allow for a reasonable balance of signal throughput with spectral resolution.

Preferably, the first photodiode and/or the second photodiode comprise(s) indium gallium arsenide or organic semiconductor materials.

The advantage of either material is that they are sensitive to the wavelengths mentioned herein and can be operated with relatively low power. Moreover, they have clear mechanisms for modifications to adjust for specific spectral features.

For example, the sensor may be an organic semiconductor based sensor manufactured by Senorics GmbH. Such sensor is, e.g., disclosed in the conference presentation of Robert Bruckner, Matthias Jahnel, David Wynands, Rico Meerheim, Ronny Timmreck, and Karl Leo "High-sensitive near-infrared organic spectroscopic photodetectors for food quality sensing (Conference Presentation)", Proc. SPIE 10738, Organic and Hybrid Sensors and Bioelectronics XI, 107380K (18 September 2018); https://doi.Org/10.l 117/12.2322354.

These sensors have a plurality of organic layers and use a cavity design for the organic layers to enhance absorption for a given range of wavelength. Combined with modifying the composition of the layers, these sensors are able to achieve distinct spectral sensitivity at different pixels.

Preferably, the visualization means are configured to display the parameter and/or a condition associated with the parameter.

More preferably, the visualization means are configured to simultaneously display the ear canal illuminated by the light emitted by the light source and the parameter and/or condition associated with the parameter. That is, the visualization means may be configured to simultaneously display the ear canal and the parameter, the ear canal and a condition associated with the parameter, or the ear canal, the parameter, and a condition associated with the parameter. In other words, the visualization means may be configured to display the ear canal and the parameter and/or condition associated with the parameter in such a way that the ear canal and the parameter and/or condition associated with the parameter are visible to the user at the same time.

Preferably, the visualization means comprises an electronic display configured to simultaneously display the ear canal and the parameter and/or condition associated with the parameter. Alternatively, the visualization means may comprise optics for displaying the ear canal and an electronic display for displaying the parameter and/or condition associated with the parameter. For example, the electronic display may be an ELD, LCD, TFT, LED, OLED, AMOLED, PDP or QLED display.

The visualization means may be controlled by the controller to display the parameter or the associated condition. In this way, the user may visually inspect the ear canal and read-out the parameter at the same time, which may improve usability of the otoscope.

Preferably, the otoscope comprises a power source for powering the light source, the spectral sensor, the controller, and optionally the visualization means.

The power source may be a battery or accumulator. In this way, the otoscope does not need to be plugged to a power source in use, which may improve usability. Alternatively or additionally, the otoscope may be configured to be plugged to an external power source.

Preferably, the otoscope comprises a beamsplitter configured to transmit a first portion of the light emitted by the light source and reflected by the ear canal to the visualization means and to reflect a second portion of the light emitted by the light source and reflected by the ear canal to the spectral sensor.

Preferably, the beamsplitter is configured to transmit 60%-80% of the light to the visualization means and reflect 20%-40% of the light to the spectral sensor.

In this way, the spectral sensor does not need to be in the light path of the visualization means. Thus, the spectral sensor does not impair the visualization of the ear canal. Moreover, the spectral sensor may be mounted in a portion of the otoscope with more available space, which may improve the form factor. Moreover, in this way, there may be space for arranging dispersing optics in the light path of the light reflected to the spectral sensor, which may improve the spectral measurement.

Preferably, the visualization means comprises visualization optics or a digital visualization device.

Preferably, the otoscope comprises a head portion and a handle, wherein the head portion comprises a speculum and the visualization means and preferably the beam splitter, and wherein the handle comprises the light source, the spectral sensor, and the controller. Furthermore, if the otoscope comprises a power source, the power source may also be provided in the handle.

In other words, the light source, the spectral sensor, the controller and preferably the power source may be integrated into the handle. In this way, the size of the head may be reduced and/or the form factor of the otoscope may be improved.

Preferably, the otoscope comprises a light guide configured to guide the light emitted by the light source to the speculum and into the ear canal.

For example, the light guide may comprise a plurality (e.g. 10-100) of fiber optic cables, a molded plastic light guide, or a hollow metallic light guide. With such light guide the light may be guided to a speculum of the otoscope. Preferably, the speculum comprises an inner member and an outer member and the light of the light source is guided through a gap, e.g. an annular gap, between the inner member and the outer member into the ear canal and the light that is reflected by the ear canal is received through the inner member for visual inspection and for the measurement of the first intensity and the second intensity.

In this way, the light source does not have to be integrated into the head and/or speculum of the otoscope such that the size of the head and/or speculum may be reduced and/or its form factor may be improved.

Preferably, the otoscope may further comprise a housing or casing enclosing at least the light source, the spectral sensor and the controller.

In other words, all components of the otoscope including the spectral sensor and the controller may be integrated into the same housing of the otoscope. In this way the form factor of the otoscope and/or its usability may be improved.

Preferably, the otoscope may further comprise optics configured to disperse the light emitted by the light source and reflected by the ear canal over the spectral sensor.

The optics may comprise one or more lenses that is/are configured to defocus the light directed to the spectral sensor. Furthermore, the optics may comprise a light diffuser, e.g., ground glass and/or a color filter. The color filter may be configured to transmit infrared light and block visible light. Preferably, the color filter may be configured to transmit light having a wavelength between 1000 nm and 1700 nm. The color filter may be arranged before or upstream of the one or more lenses and the light diffuser may be arranged after or downstream of the one or more lenses.

In this way, it may be ensured that the light is evenly distributed over the whole spectral sensor. In this way, all intensities, may be measured with the same preciseness, such that the reliability of the otoscope may be improved.

Preferably, the spectral sensor is configured to measure n intensities in n spectral ranges, wherein n is between 6 and 10.

The use of several spectral ranges enables discrimination between spectral signatures similar to water, and alternative use modes designed for different target molecules.

Preferably, the controller is configured to determine the reflectance by water on the basis of the first intensity and to compensate for one or more of background, changing light levels, varying distance to the object of interest, and other artifacts on the basis of the second intensity, preferably the other intensities.

For example, in a simple case, the controller is configured to fit the parameter with a linear regression of a physical model. The physical model may include the parameter (“first parameter”), which may relate to the reflectance of water. Moreover, the model may include a further parameter (“second parameter”), which may relate to background. The first parameter and the second parameter may be fitted such that the physical model is consistent with the first and second intensity measured by the spectral sensor. The controller may also be configured to perform higher-order regressions methods for determining the parameter, which may also be trained against a large set of experimental data.

Alternatively or additionally, the controller may be configured to perform ratiometric methods for comparing the first and second intensity.

Further and/or additional embodiments and features of the invention are disclosed in the following aspects:

1. Otoscope, comprising: a light source configured to emit light to illuminate an ear canal; visualization means configured to display the ear canal illuminated by the light emitted by the light source for visual inspection of the ear canal by a user; a spectral sensor configured to measure intensities of the light emitted by the light source and reflected by the ear canal, the spectral sensor being configured to measure at least a first intensity in a first spectral range and a second intensity in a second spectral range; a controller configured to calculate a parameter on the basis of the first intensity and the second intensity.

2. Otoscope according to aspect 1, wherein the parameter relates to an amount of water behind the ear drum. 3. Otoscope according to any one of the preceding aspects, wherein the light emitted by the light source has a spectral range spanning over at least 1400 nm to 1500 nm, preferably 600 nm to 1700 nm, more preferably 400 nm to 1700 nm.

4. Otoscope according to any one of the preceding aspects, wherein the light source comprises a tungsten-filament light bulb, a number of light- emitting diodes, or some mixture thereof.

5. Otoscope according to any one of the preceding aspects, wherein the first spectral range is between 1400 nm and 1550 nm, preferably between 1450 nm and 1500 nm, more preferably around 1470 nm; and/or wherein the second spectral range is between 1200 nm and 1400 nm, more preferably between 1200 nm and 1350 nm, even more preferably around 1250 nm.

6. Otoscope according to any one of the preceding aspects, wherein the spectral sensor comprises at least a first photodiode configured to measure the first intensity a second photodiode configured to measure the second intensity.

7. Otoscope according to aspect 6, wherein the first photodiode comprises a first band-pass filter and the second photodiode comprises a second band-pass filter.

8. Otoscope according to aspect 7, wherein the first band-pass filter and/or the second band-pass filter have/has a full- width-half-maximum of 150 nm or less, preferably between 10 nm and 30 nm, more preferably, between 15 nm and 25 nm, even more preferably between 18 nm and 22 nm.

9. Otoscope according to any one of aspects 6 to 8, wherein the first photodiode and/or the second photodiode comprise(s) indium gallium arsenide or organic semiconductor materials.

10. Otoscope according to any one of the preceding aspects, wherein the visualization means are configured to display the parameter and/or a condition associated with the parameter.

11. Otoscope according to aspect 10, wherein the visualization means are configured to simultaneously display the ear canal illuminated by the light emitted by the light source and the parameter and/or condition associated with the parameter.

12. Otoscope according to any one of the preceding aspects, further comprising: a power source for powering the light source, the spectral sensor, the controller, and optionally the visualization means.

13. Otoscope according to any one of the preceding aspects, further comprising: a beamsplitter configured to transmit a first portion of the light emitted by the light source and reflected by the ear canal to the visualization means and to reflect a second portion of the light emitted by the light source and reflected by the ear canal to the spectral sensor.

14. Otoscope according to any one of the preceding aspects, wherein the visualization means comprises visualization optics or a digital visualization device.

15. Otoscope according to any one of the preceding aspects, comprising a head portion and a handle; wherein the head portion comprises a speculum and the visualization means and preferably the beam splitter; wherein the handle comprises the light source, the spectral sensor, and the controller and preferably the power source.

16. Otoscope according to aspect 15, further comprising a light guide configured to guide the light emitted by the light source to the speculum and into the ear canal.

17. Otoscope according to any one of the preceding aspects, further comprising a housing enclosing at least the light source, the spectral sensor and the controller.

18. Otoscope according to any one of the preceding aspects, further comprising optics configured to disperse the light emitted by the light source and reflected by the ear canal over the spectral sensor.

19. Otoscope according to any one of the preceding aspects, wherein the spectral sensor is configured to measure n intensities in n spectral ranges, wherein n is between 4 and 20, preferably between 6 and 12.

20. Otoscope according to any one of the preceding aspects, wherein the controller is configured to determine the absorbance of light by water on the basis of the first intensity and to compensate for one or more of background, changing light levels, varying distance to the object of interest, and other artifacts on the basis of the second intensity, preferably the other intensities.

Further embodiments and features of the invention are disclosed in the exemplary embodiments and the drawings.

Brief description of drawings

Exemplary embodiments of the invention are shown in the drawings and are discussed with reference to the following figures, in which like reference numerals refer to identical, similar or equivalent elements. The invention is not limited to the exemplary embodiments.

Fig. 1 shows a schematic drawing of an otoscope according to an exemplary embodiment;

Fig. 2 shows a schematic drawing of a spectral sensor according to an exemplary embodiment;

Fig. 3 A shows a schematic drawing of an otoscope according to an exemplary embodiment in side view; and

Fig. 3B shows a front view of the otoscope of Fig. 3 A.

Description of exemplary embodiments

Fig. 1 shows an otoscope 100 according to an exemplary embodiment. The otoscope inter alia comprises a light source 108 configured to emit light that is directed or guided into a patient’s ear canal to illuminate the ear canal in use, visualization means 106 configured to display the ear canal as the ear canal is illuminated by the light source 108, and a spectral sensor 110 configured to measure at least a first intensity in a first spectral range and a second intensity in a second spectral range of the light emitted by the light source 108 and reflected by the patient’s ear canal, and a controller configured to calculate a parameter on the basis of the first intensity and the second intensity.

Although the controller 112, the light source 108 and the spectral sensor 110 are shown as separate units, they may, e.g., all be provided on the same printed circuit board. Alternatively, they may be provided as separate units, e.g., on separate printed circuit boards.

The visualization means 106 may comprise analogue visualization means, e.g., a lens or lens system, digital visualization means, e.g., a digital image sensor and a display, or both. The visualization means 106 further comprises a portion 124 controlled by the controller 112 to display the parameter or a condition associated with the parameter. For example, if the visualization means 106 is analogue and comprises a lens or lens system, the portion 124 may comprise a display panel positioned within the field of vision. If the visualization means 106 is digital and already comprises a display, said display may be used for displaying the parameter or associated condition.

The otoscope 100 comprises a head portion 102 and a handle 104. The handle 104 is configured to allow a user to grasp the otoscope 100 for the inspection of a patient’s ear. The head portion 102 comprises a speculum 116 configured for at least partial insertion into the ear canal. Furthermore, the head portion 102 comprises the visualization means 106 and a beam splitter 122.

Moreover, the speculum 116 comprises an outer member 118 and an inner member 120, such that an annular gap is formed between the outer member 118 and the inner member 120. The light emitted by the light source 108 is guided through said annular gap formed between the outer member 118 and the inner member 120 into the patient’s ear canal in use. For this purpose, the otoscope 100 may comprise a light guide (not shown) arranged between the light source 108 and the proximal tip of the speculum 116 and extending through the annular gap. Said light guide may, e.g., comprise a plurality of fiber optic cables, a molded plastic light guide, or a hollow metallic light guide.

Furthermore, in use, light reflected by the ear canal enters through the inner member 120. A first portion of said light is transmitted by a beamsplitter 122 located in the head portion 102 to the visualization means 106. Thus, the first portion of the light reflected by the ear canal is used to visualize the ear canal. A second portion of the light is reflected by the beamsplitter 122 to the spectral sensor 110. Thus, a second portion of the light reflected by the ear canal is used to conduct the spectral analysis.

Moreover, in front of the spectral sensor 110, i.e. upstream, the otoscope 100 comprises dispersing optics 128, which, e.g., comprise one or more lenses that is/are configured to defocus the light directed to the spectral sensor, a diffuser, e.g., ground glass, and/or a color filter.

The otoscope 100 further comprises a power source 114 for providing the light source 108, the spectral sensor 110, optionally the visualization means 106, and the controller 112 with electrical energy.

All components of the otoscope 100 are entirely or at least partly enclosed by a housing or casing 126 of the otoscope 100. Said housing 126 may comprise one or more housing parts.

Fig. 2 shows a spectral sensor 110 according to an exemplary embodiment. The spectral sensor comprises a plurality of pixels 200, here pixels 1 to 8. Each pixel 200 comprises a photodiode having a specific band-pass filter. For example, the band-pass filters of the pixels 1 to 8 may be such that each of the pixels has a full-width-half-maximum between 10 nm and 30 nm. Thus the entire spectral sensor 110 may cover a spectral range of 800 nm to 2400 nm. One of the pixels 1 to 8 comprises a band-pass filter having its maximum around 1470 nm, such that that pixel is configured to measure the absorbance of light by water at 1470 nm.

Figs. 3 A and 3B show an otoscope 100 to an exemplary embodiment. With regard to the elements of the otoscope of Figs. 3 A and 3B denoted with the same reference signs as used in Figs. 1 and 2, it is referred to the description of the embodiments of Figs. 1 and 2.

In the following only the additional elements of the otoscope are described. As can be seen, the light source 108 and the spectral sensor 110 are provided on a printed circuit board 306. Moreover, also the controller (not shown) may be provided on the printed circuit board 306. The printed circuit board is 306 provided in an upper portion of the handle that is arranged underneath the head portion 102 of the otoscope 100. The upper portion of the handle 104 and the head portion 102 shown in Fig. 3 A may form one unit, which is connectable to a lower portion of the handle (not shown), by means of a threaded adapter 312. The lower portion of the handle (not shown) may comprise the power source or battery unit.

While the light source 108 and the spectral sensor 110 are shown to be located on the same printed circuit board 306, they may also be provided on separate printed circuit boards. However, providing the light source 108 and the spectral sensor 110 on the same printed circuit board 306 may have the advantage that both may be controlled by the same controller (not shown), which may also be provided on circuit board 306.

Furthermore, the head portion comprises a light guide in the form of a plurality of optical fibers 304, which are attached to a terminal 302 and extend into the annular gap between the inner member 120 and the outer member 118 of the speculum and to the tip of the speculum. The terminal may be located at a lower end of the head portion 102 or speculum 116, i.e. adjacent to the handle portion 104. In this way, the light emitted from the light source 108 is guided through the annular gap between inner member 120 and outer member 118 to the proximal tip of the speculum and into the patient’s ear canal in use.

Fig. 3B shows a front view of the otoscope’s head portion 102. As can be seen, the speculum comprises an outer member 118 and an inner member 120, between which an annular gap 308 is formed. The optical fibers 304 extend through the annular gap 308 to the tip of the speculum 116. Thus, the light emitted by the light source 108 is guided through the annular gap 308. The light is then reflected by the ear canal and may enter the otoscope through the opening 310 of the inner member 120.

In this document, he terms “upper”, “lower”, “top” and “bottom” refer to a direction from an end of the otoscope at the handle to an opposite end of the otoscope at the head portion. Thus, the “top” refers to the end of the otoscope at the head portion and the “bottom” refers to the end of the otoscope at the handle. An “upper” part or portion is at or closer to the “top” head portion and a “lower” part or portion is at or closer to the “bottom” of the handle portion.

The terms “proximal” and “distal” refer to the directions towards and away from the patient in use. Thus, a “proximal” part or portion is closer to the patient in use than a “distal” part or portion. For example, a speculum of the otoscope may be more proximal than visualization means of the otoscope.

The term “reflectance” refers to the fraction of light reflected by a structure, e.g., the ear canal or any fluid contained therein. The term “absorbance” refers to the fraction of light absorbed by a structure, e.g., the ear canal or any fluid contained therein.

Although the invention herein has been described with reference to particular exemplary embodiments, it is to be understood that these exemplary embodiments are merely illustrative of the principles and applications of the invention. It is therefore to be understood that numerous modifications may be made to the embodiments and that other arrangements may be devised without departing from the scope of the invention.

Claims

1. Otoscope (100), comprising: a light source (108) configured to emit light to illuminate an ear canal; visualization means (106) configured to display the ear canal illuminated by the light emitted by the light source (108) for visual inspection of the ear canal by a user; a spectral sensor (110) configured to measure intensities of the light emitted by the light source (108) and reflected by the ear canal, the spectral sensor (110) being configured to measure at least a first intensity in a first spectral range and a second intensity in a second spectral range; a controller (112) configured to calculate a parameter on the basis of the first intensity and the second intensity.

2. Otoscope (100) according to claim 1, wherein the parameter relates to an amount of water behind the ear drum.

3. Otoscope (100) according to any one of the preceding claims, wherein the light emitted by the light source (108) has a spectral range spanning over at least 1400 nm to 1500 nm, preferably 600 nm to 1700 nm, more preferably 400 nm to 1700 nm.

4. Otoscope (100) according to any one of the preceding claims, wherein the light source (108) comprises a tungsten-filament light bulb, a number of light-emitting diodes, or some mixture thereof.

5. Otoscope (100) according to any one of the preceding claims, wherein the first spectral range is between 1400 nm and 1550 nm, preferably between 1450 nm and 1500 nm, more preferably around 1470 nm; and/or wherein the second spectral range is between 1200 nm and 1400 nm, more preferably between 1200 nm and 1350 nm, even more preferably around 1250 nm.

6. Otoscope (100) according to any one of the preceding claims, wherein the spectral sensor (110) comprises at least a first photodiode configured to measure the first intensity a second photodiode configured to measure the second intensity; and wherein, preferably, the first photodiode and/or the second photodiode comprise(s) indium gallium arsenide or organic semiconductor materials.

7. Otoscope (100) according to claim 6, wherein the first photodiode comprises a first band-pass filter and the second photodiode comprises a second band-pass filter; wherein, preferably, the first band-pass filter and/or the second band-pass filter have/has a full-width-half-maximum of 150 nm or less, preferably between 10 nm and 30 nm, more preferably, between 15 nm and 25 nm, even more preferably between 18 nm and 22 nm.

8. Otoscope (100) according to any one of the preceding claims, wherein the visualization means (106) comprises visualization optics or a digital visualization device; and/or wherein the visualization means (106) are configured to simultaneously display the ear canal illuminated by the light emitted by the light source (108) and the parameter and/or a condition associated with the parameter.

9. Otoscope (100) according to any one of the preceding claims, further comprising: a power source (114) for powering the light source (108), the spectral sensor (110), the controller (112), and optionally the visualization means (106).

10. Otoscope (100) according to any one of the preceding claims, further comprising: a beamsplitter (122) configured to transmit a first portion of the light emitted by the light source (108) and reflected by the ear canal to the visualization means (106) and to reflect a second portion of the light emitted by the light source (108) and reflected by the ear canal to the spectral sensor (110).

11. Otoscope (100) according to any one of the preceding claims, comprising a head portion (102) and a handle (104); wherein the head portion (102) comprises a speculum (116) and the visualization means (106) and preferably the beam splitter (122); wherein the handle (104) comprises the light source (108), the spectral sensor (110), and the controller (112) and preferably the power source (114).

12. Otoscope (100) according to claim 11, further comprising a light guide (304) configured to guide the light emitted by the light source (108) to the speculum (116) and into the ear canal.

13. Otoscope (100) according to any one of the preceding claims, further comprising a housing (126) enclosing at least the light source (108), the spectral sensor (110) and the controller (112).

14. Otoscope (100) according to any one of the preceding claims, further comprising optics (128) configured to disperse the light emitted by the light source (108) and reflected by the ear canal over the spectral sensor (110).

15. Otoscope (100) according to any one of the preceding claims, wherein the spectral sensor (110) is configured to measure n intensities in n spectral ranges, wherein n is between 4 and 20, preferably between 6 and 12.