Medical apparatus

Abstract

To provide a medical apparatus that facilitates objective determination of a normal part and a lesion part on a biological tissue surface inside a living body without the need to collect samples.SOLUTION: A medical apparatus 1 includes: a capsule endoscope 2 which has a permanent magnet 21 that generates power when a magnetic field is applied, and an outer shell 22 that can contact or approach a biological tissue surface WA with the power, and has a light irradiation unit 23, an imaging unit 24, and a communication unit 25; a control device 3 which generates the magnetic field to control three-dimensional movement of the capsule endoscope 2, and is capable of communicating with the capsule endoscope 2. The apparatus measures: physical properties of the biological tissue surface WA when the outer shell 22 contacts the biological tissue surface WA and applies force to it; optical properties of a biosensor 22d when the outer shell 22 of the capsule endoscope 2 has the biosensor 22d and the biosensor 22d contacts the biological tissue surface WA; or optical properties of reflected light when the outer shell 22 of the capsule endoscope 2 approaches the biological tissue surface WA and the light irradiation unit 23 irradiates the biological tissue surface WA with light.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a medical device for performing in vivo examinations. [Background technology]

[0002] In recent years, in addition to medical devices using endoscopes (normal endoscopes) for the examination of the stomach, intestines, and the like in a living body, medical devices using capsule endoscopes, which have the advantage of being less painful than endoscopes, are known. A medical device using a capsule endoscope has a light irradiation unit, an imaging unit, and a communication unit inside the outer shell of the capsule endoscope, and can obtain external images of the surface of biological tissue in a living body by the light irradiation unit and the imaging unit, and can communicate with a control device outside the living body to play back the external images and receive commands from the control device by the communication unit (see Patent Documents 1 and 2). After the subject swallows the capsule endoscope through the mouth, it passively moves inside the living body by the peristaltic movement of the stomach and intestines (see Patent Document 1). In addition, when a permanent magnet is provided in the capsule endoscope, a magnetic field is applied from a control device outside the living body to generate power in the permanent magnet, and the capsule endoscope can be guided to a position in the living body where an examination is desired (see Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-237639 A [Patent Document 2] JP 2013-66694 A [Patent Document 3] JP 2009-273777 A [Patent Document 4] JP 2014-202574 A [Non-patent literature]

[0004] [Non-Patent Document 1] Yusuke Takashima and 2 others, "Highly sensitive refractive index sensor using GaN subwavelength gratings operating in the 400 nm wavelength band," Proceedings of the 67th Spring Meeting of the Japan Society of Applied Physics, Japan Society of Applied Physics, 2020 Summary of the Invention [Problem to be solved by the invention]

[0005] However, medical devices using conventional capsule endoscopes generally rely on a subjective method in which a doctor visually judges whether there is a normal area or a diseased area on the surface of the biological tissue inside the living body based on the characteristics of the external image and his / her experience, thereby posing problems such as overlooking diseased areas and being affected by the doctor's experience and skill.

[0006] The present inventors conducted extensive research and created the present invention by focusing on the fact that diseased and normal parts of a living body that can be palpated have different hardness (see Patent Document 3), that the optical properties of a biosensor differ between samples taken from diseased and normal parts (see Patent Document 4), and that when light is irradiated onto a material from a light irradiating section having a periodic structure ("nanostructure") smaller than the wavelength of light, the reflected light has different optical properties depending on the material (see Non-Patent Document 1).

[0007] The present invention has been made in consideration of the above-mentioned circumstances, and its object is to provide a medical device that makes it easy to objectively determine normal and diseased areas on the surface of biological tissue in a living body without taking samples. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the medical device described in claim 1 comprises a capsule endoscope having a permanent magnet that generates power when a magnetic field is applied thereto, an outer shell that can contact or approach the surface of biological tissue inside a living body by the power, the outer shell having a light irradiation unit, an imaging unit, and a communication unit inside the outer shell, and a control device that generates the magnetic field to control the three-dimensional movement, orientation, and position of the capsule endoscope and is capable of communicating with the communication unit of the capsule endoscope, and measures the physical characteristics of the surface of the biological tissue when the outer shell of the capsule endoscope contacts the surface of the biological tissue and applies a force to the surface of the biological tissue, or the optical characteristics of the biosensor when the outer shell of the capsule endoscope has a biosensor and the biosensor contacts the surface of the biological tissue, or the optical characteristics of the reflected light when the outer shell of the capsule endoscope approaches the surface of the biological tissue and the light irradiation unit irradiates the surface of the biological tissue with light.

[0009] The medical device of claim 2 is the medical device of claim 1, wherein the physical property is an elastic property or hysteresis property of the biological tissue surface, and is obtained by measuring the indentation of the biological tissue surface while the outer shell applies the force having a component perpendicular to the biological tissue surface, or the physical property is a friction property of the biological tissue surface, and is measured by measuring the force at which the capsule endoscope starts to move while the outer shell applies the force parallel to the biological tissue surface.

[0010] The medical device of claim 3 is the medical device of claim 1, wherein the biosensor of the outer shell has an uneven portion of a periodic structure containing a recognition element formed on its outer surface, and the optical characteristics are measured by irradiating the biosensor with measurement light from the light irradiation unit, and fluorescence emission, light absorption, scattering, or diffraction may occur in the uneven portion depending on the surface of the biological tissue with which it comes into contact, and the imaging unit receives the reflected light from the uneven portion.

[0011] The medical device of claim 4 is the medical device of claim 1, wherein the light irradiating unit has a measurement light irradiator having a surface formed with uneven portions having a periodic structure smaller than the wavelength of light, and receives and measures reflected light when the measurement light irradiator irradiates light onto the surface of the biological tissue. Effect of the Invention

[0012] According to the medical device of the present invention, physical or optical properties are quantitatively measured on the surface of biological tissue inside a living body without taking a sample, making it easy to objectively determine whether normal or diseased areas are present. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram showing a medical device according to an embodiment of the present invention together with a subject; [Diagram 2] Schematic diagram of a capsule endoscope of the above-mentioned medical device, in which (a) is a side view, (b) is a side view when it is in vertical contact with the surface of biological tissue inside a living body, and (c) is a side view when it is in oblique contact with the surface of biological tissue inside a living body. [Diagram 3] 1A is a schematic diagram of a capsule endoscope of the above-mentioned medical device, in which (a) is a side view when a force is applied perpendicularly to the surface of biological tissue inside a living body, and (b) is a side view when a force is applied obliquely to the surface of biological tissue inside a living body. [Figure 4] FIG. 1 is a schematic side view of a capsule endoscope of the above-mentioned medical device when a protrusion portion is provided, where (a) shows the case where the protrusion portion is approximately cylindrical, and (b) shows the case where the protrusion portion is approximately conical (or approximately triangular pyramid-shaped or approximately triangular prism-shaped). [Diagram 5] 1 is a graph showing schematic diagrams of physical properties of a biological tissue surface, where (a) shows elastic properties and (b) shows hysteresis properties. [Figure 6] FIG. 2 is a side view showing a schematic diagram of the capsule endoscope of the medical device according to the first embodiment, in which a pressure gauge is provided. [Figure 7] 1A is a schematic diagram of a capsule endoscope of the above-mentioned medical device, in which (a) is a side view in which a biosensor is attached to the outside of the transparent front part of the outer shell, and (b) is a side view in which the biosensor is part of the front part of the outer shell. [Figure 8A]1A and 1B are enlarged views of a portion of a biosensor of a capsule endoscope of the medical device as described above, as viewed from the front, where FIG. 1A shows a case in which the recess is square-shaped, and FIG. 1B shows a case in which the recess is strip-shaped. [Figure 8B] These are cross-sectional views (side cross-sectional views) of Figure 8A, where (a) is taken along the plane indicated by AA in Figure 8A(a), and (b) is taken along the plane indicated by BB in Figure 8A(b). [Figure 9A] FIG. 13 is an enlarged front view of a portion of the measurement light irradiator of the capsule endoscope of the medical device, where (a) shows the case where the recess is square-shaped, and (b) shows the case where the recess is strip-shaped. [Figure 9B] These are cross-sectional views (side cross-sectional views) of Figure 9A, where (a) is taken along the plane indicated by CC in Figure 9A(a), and (b) is taken along the plane indicated by DD in Figure 9A(b). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described. As shown in Fig. 1, a medical device 1 according to an embodiment of the present invention includes a capsule endoscope 2 and a control device 3. A subject PE can take an examination after swallowing the capsule endoscope 2 through the mouth or inserting it through the anus to take it into the living body. The control device 3 is provided outside the living body.

[0015] As shown in Fig. 2(a), the capsule endoscope 2 includes a permanent magnet 21, an outer shell 22, a light emitting unit 23, an imaging unit 24, and a communication unit 25. It is also possible to include a power supply unit that supplies power to the light emitting unit 23, the imaging unit 24, the communication unit 25, etc. In Fig. 2(a) (and other figures), the permanent magnet 21 and the communication unit 25 are indicated by dashed lines.

[0016] The permanent magnet 21 generates power when a magnetic field is applied. The permanent magnet 21 is usually provided so that its magnetization direction coincides with the longitudinal direction (axial direction) of the outer shell 22 described later, but may coincide with the radial direction of the outer shell 22. The shape and size of the permanent magnet 21 are not particularly limited, and it may be, for example, a circular disk shape when viewed from the front of the capsule endoscope 2 (FIG. 2(a) shows its side view). The permanent magnet 21 may be provided inside the outer shell 22 (see FIG. 2(a)), and generates power when a magnetic field is applied. In the case where the capsule endoscope 2 is provided with a fin portion as disclosed in Patent Document 2, the permanent magnet 21 may be provided in the fin portion as a rod-like object extending in the magnetization direction, and power (oscillation) may be generated when a magnetic field is applied.

[0017] The outer shell 22 can contact (see Figs. 2(b) and (c)) or approach the surface WA of biological tissue inside a living body by the power of the permanent magnet 21. The front part 22a of the outer shell 22 is usually transparent. Other parts of the outer shell 22 (such as the side surfaces) can also be made transparent. The shape and size of the outer shell 22 are not particularly limited, but it can be, for example, roughly cylindrical with a length in the front-back direction (longitudinal direction) of about 20 mm to 30 mm and a diameter (diameter in the direction perpendicular to the front-back direction) of about 5 mm to 15 mm. The contact angle θ in Fig. 2(c) of 90 degrees corresponds to the state in Fig. 2(b).

[0018] The light irradiating unit 23, the imaging unit 24, and the communication unit 25 are provided inside the outer shell 22. The light irradiating unit 23 can irradiate light that illuminates the biological tissue surface WA inside the living body, as well as light required for measuring physical properties or optical properties. The imaging unit 24 can acquire an external photographed image of the biological tissue surface WA, as well as an image photographed in measuring physical properties or optical properties. The communication unit 25 wirelessly communicates with the control device 3, and can cause the control device 3 to play back the external photographed image or the image photographed in measuring physical properties or optical properties, or can control the light irradiating unit 23 and the imaging unit 24 in response to a command from the control device 3.

[0019] Special structures adapted to the measurement of physical properties or the measurement of optical properties in the outer shell 22 and the light irradiating portion 23 will be described in the section on the measurement of physical properties or the section on the measurement of optical properties described later.

[0020] The control device 3 generates a magnetic field to control the three-dimensional movement, orientation, and position of the capsule endoscope 2, and is capable of communicating with the communication unit 25 of the capsule endoscope 2.

[0021] The control device 3 can be provided with coils on six faces, i.e., a pair of x-axis coils 3x, 3x' that generate a magnetic field in the x-axis direction, a pair of y-axis coils 3y, 3y' that generate a magnetic field in the y-axis direction, and a pair of z-axis coils 3z, 3z' that generate a magnetic field in the z-axis direction (see FIG. 1). In this way, when the medical device 3 has coils on six faces, the three-dimensional movement, orientation, and position of the capsule endoscope 2 can be controlled with high precision. Note that, for convenience of illustration, the x-axis coil 3x' located on the front side of the page is omitted in FIG. 1.

[0022] The control device 3 may have a communicator 31 that wirelessly communicates with the communication unit 25 of the capsule endoscope 2. The control device 3 may also have a control processor 32 that controls the pair of x-axis coils 3x, 3x', the pair of y-axis coils 3y, 3y', the pair of z-axis coils 3z, 3z', and the communicator 31. The control processor 32 has a CPU 32a, a program memory unit 32b, a work memory unit 32c, an interface unit 32d, and the like (see FIG. 1). In the control processor 32, the CPU 32a performs necessary processing using the work memory unit 32c in accordance with various programs stored in the program memory unit 32b, and also exchanges necessary data through the interface unit 32d.

[0023] When the examiner who examines the subject PE grasps the orientation and position of the capsule endoscope 2 with respect to the surface WA of the biological tissue in the living body by analyzing the external photographed image sent from the capsule endoscope 2, the examiner can operate the magnetic field of the control device 3 to control the three-dimensional movement, orientation and position of the capsule endoscope 2 so that the outer shell 22 of the capsule endoscope 2 comes into contact with or approaches the surface WA of the biological tissue in the living body. Also, while analyzing the photographed image sent from the capsule endoscope 2 for measuring the physical properties or the optical properties, the examiner can operate the magnetic field of the control device 3 to control the orientation and position of the capsule endoscope 2 with respect to the surface WA of the biological tissue, or communicate with the capsule endoscope 2 to control the light irradiation unit 23 and the imaging unit 24.

[0024] Next, the measurement of the physical characteristics will be described in detail. In the medical device 1, the outer shell 22 of the capsule endoscope 2 comes into contact with the biological tissue surface WA, and further, a force can be applied to the biological tissue surface WA by the power of the permanent magnet 21, and the physical characteristics of the biological tissue surface WA at that time can be measured. Note that the measurement of the physical characteristics may be performed with an accuracy at least to the extent that a difference is observed between normal and diseased parts of the biological tissue surface WA.

[0025] When measuring physical properties, it is preferable that the front part 22a of the outer shell 22 is dome-shaped (smoothly convex) (see Figs. 2(a)-(c)). In this case, as shown in Figs. 3(a) and (b), the front part 22a of the outer shell 22 is easily brought into contact with the biological tissue surface WA to apply force to the biological tissue surface WA. Alternatively, as shown in Figs. 4(a) and (b), the outer shell 22 may have a protruding part 22b that comes into contact with the biological tissue surface WA and then applies force. The protruding part 22b may be transparent. Note that the shape of the protruding part 22b is not limited to that shown in Figs. 4(a) and (b). Also, the protruding part 22b is provided at the center of the front part 22a in Figs. 4(a) and (b), but is not limited thereto, and may be provided at any position of the outer shell 22 as long as it can be observed by the imaging unit 24.

[0026] The physical property can be the elastic property or the hysteresis property of the biological tissue surface WA. In the biological tissue surface WA, for example, the normal part shows the elastic property as shown by the curve a in FIG. 5(a), and the diseased part shows the elastic property as shown by the curve b in FIG. 5(a). Young's modulus E can also be used as an index of the elastic property. In addition, in the biological tissue surface WA, for example, the normal part does not show the hysteresis property as shown by the curve c in FIG. 5(b), and the diseased part shows the hysteresis property as shown by the curve d in FIG. 5(b).

[0027] The elasticity or hysteresis characteristic is obtained by measuring the depression of the tissue surface WA while the outer shell 22 applies a force having a perpendicular component to the tissue surface WA.

[0028] At this time, the component of the force perpendicular to the surface of the biological tissue WA can be calculated from the magnitude and direction of the magnetic field generated by the control device 3 and the strength of the magnetic force of the permanent magnet 21. Here, the magnitude and direction of the magnetic field generated by the control device 3 can be obtained from the current values ​​passed through each of the pair of x-axis coils 3x, 3x', the pair of y-axis coils 3y, 3y', and the pair of z-axis coils 3z, 3z', or can be obtained from values ​​measured by a magnetic flux density measuring device installed outside the body. It is also possible to provide a pressure gauge 22c to measure the component of the force perpendicular to the surface of the biological tissue WA. For example, the pressure gauge 22c can be provided as a part of the outer shell 22 at the rear of the front part 22a (see FIG. 6) or at another part of the outer shell 22 so as to receive the pressure received by the front part 22a.

[0029] The depression on the biological tissue surface WA can be measured by observing the penetration depth of the transparent outer shell 22 (if it has protruding parts 22b, then the protruding parts 22b) into the biological tissue surface WA and the boundary part (the boundary part between the penetrated part and the non-penetrated part) with the imaging part 24. At this time, in order to measure the size of the depression, a scale can be selectively displayed by adding a scale to the transparent outer shell 22 (if it has protruding parts 22b, then the protruding parts 22b), adding a scale to the light irradiated from the light irradiating part 23 or the image captured by the imaging part 24, or adding a scale to the image reproduced by the control device 3.

[0030] Alternatively, the physical characteristic may be the friction characteristic of the biological tissue surface WA. The friction characteristic may be obtained by measuring the parallel component of the force (maximum friction force) until the capsule endoscope 2 starts to move when the outer shell 22 applies a force having a component parallel to the biological tissue surface WA in a state where the outer shell 22 is in contact with the biological tissue surface WA as shown in Fig. 2(b) and (c), or by measuring the parallel component of the force (force corresponding to the kinetic friction force) required to continue the movement of the outer shell 22 after the outer shell 22 starts to move. Specifically, for example, the applied force is kept constant, and the contact angle θ is gradually decreased from the state shown in Fig. 2(b) or Fig. 2(c) to increase the parallel component, and when the outer shell 22 starts to move at a certain contact angle θc, the parallel component of the force at that time (maximum friction force) can be measured, and the parallel component of the force (force corresponding to the kinetic friction force) required to continue the movement while maintaining the contact angle θc can be measured. The static friction coefficient can be calculated as cot(θc).

[0031] At this time, the force on the biological tissue surface WA can be calculated from the magnitude and direction of the magnetic field generated by the control device 3 and the strength of the magnetic force of the permanent magnet 21. Also, similar to the case of measuring the perpendicular component, it is possible to measure the parallel component of the force on the biological tissue surface WA by providing the pressure gauge 22c.

[0032] In this way, the medical device 1 can quantitatively measure the physical properties of the biological tissue surface WA in a living body without taking a sample, thereby facilitating the objective determination of normal and diseased areas.

[0033] Next, the measurement of the optical characteristics will be described in detail. First, the measurement of the first optical characteristic will be described, and then the measurement of the second optical characteristic will be described.

[0034] In the measurement of the first optical characteristic, the medical device 1 can measure the optical characteristic of the biosensor 22d when the outer shell 22 of the capsule endoscope 2 has the biosensor 22d and the biosensor 22d comes into contact with the biological tissue surface WA. Note that the measurement of the optical characteristic may be performed with an accuracy sufficient to show a difference between a normal part and a diseased part of the biological tissue surface WA.

[0035] In the case of measuring the first optical property, the outer shell 22 may include a biosensor 22d, which may be attached to the outside (front) of the transparent front portion 22a of the outer shell 22 as shown in Fig. 7(a) or may be part of the outer shell 22, such as the front portion 22a, as shown in Fig. 7(b).

[0036] As shown in Fig. 8A(a), (b) and Fig. 8B(a), (b), the biosensor 22d may have a periodic structure with a concave-convex portion 22da formed on its outer surface, which contains a recognition element. The recognition element is an enzyme or a protein that specifically binds to a chemical substance or a biological substance in a diseased area. The periodic structure with a concave-convex portion 22da functions as a photonic crystal that reflects a light component of a specific wavelength according to the period of the periodic structure when a measurement light is irradiated. The arrangement pattern of the concave-convex portion 22daa of the concave-convex portion 22da is not limited to those shown in Fig. 8A(a) and (b). For example, the concave-convex portion 22daa in Fig. 8A(a) may be circular, or the concave-convex portion may be reversed.

[0037] When measuring the first optical characteristic, the light irradiating unit 23 irradiates the biosensor 22d with light for measurement. This light for measurement can usually be different (having a different optical spectrum) from the illumination light for acquiring an external photographed image by the imaging unit 24. In this case, the light for measurement can be emitted by a light emitting element provided separately from the light emitting element for the illumination light.

[0038] The measurement light is irradiated onto the uneven portion 22da, and light of a specific wavelength according to the period of the periodic structure of the uneven portion 22da is reflected, and the reflected light is received by the imaging unit 24. Here, if the measurement light is irradiated onto the uneven portion 22da after passing through the base portion 22db (the portion inside the uneven portion 22da) of the biosensor 22d, the measurement light can be easily irradiated onto the uneven portion 22da from the light irradiating unit 23 provided inside the outer shell 22.

[0039] When a chemical substance or a biological substance in a diseased part of the biological tissue surface WA binds to the recognition element contained in the biosensor 22d, fluorescence emission, light absorption, scattering, or diffraction occurs in the uneven part 22da, and the optical characteristics such as the wavelength, intensity, and spectrum of the reflected light change compared to the normal part. Information on the characteristics of the reflected light received by the imaging unit 24 can be wirelessly transmitted to the control device 3 through the communication unit 25 and processed.

[0040] Next, the measurement of the second optical characteristic will be described. In the measurement of the second optical characteristic, the medical device 1 can measure the optical characteristic of the reflected light when the outer shell 22 of the capsule endoscope 2 approaches the biological tissue surface WA and the light irradiating unit 23 irradiates the biological tissue surface WA with light. Note that the measurement of the optical characteristic may be performed with an accuracy sufficient to show a difference between a normal part and a diseased part of the biological tissue surface WA.

[0041] In the case of measuring the second optical characteristic, the light irradiation unit 23 can have a measurement light irradiator 23a. As shown in Fig. 9A(a), (b) and Fig. 9B(a), (b), the measurement light irradiator 23a has a surface on which a concave-convex portion 23aa having a periodic structure equal to or smaller than the wavelength of the irradiated light is formed. The concave-convex portion 23aa can be, for example, an array pattern of concaves 23aaa as shown in Fig. 9A(a) and (b), but is not limited thereto.

[0042] When measuring the second optical characteristic, the measurement light irradiator 23a irradiates the biological tissue surface WA with measurement light from the base portion 23ab (the portion inside the uneven portion 23aa) through the uneven portion 23aa. The light that passes through the uneven portion 23aa is irradiated onto the biological tissue surface WA with light of a specific wavelength according to the period of the periodic structure of the uneven portion 23aa, and the reflected light is received by the imaging unit 24. Here, the interaction between the irradiated light and the properties of the diseased area of ​​the biological tissue surface WA causes fluorescence emission, light absorption, scattering, or diffraction, and the optical characteristics of the reflected light, such as the wavelength, intensity, and spectrum, change compared to normal areas.

[0043] In this way, by measuring the first optical property or the second optical property, the medical device 1 can quantitatively measure the optical properties on the surface WA of biological tissue inside a living body without taking a sample, thereby facilitating the objective determination of normal and diseased areas.

[0044] Although the medical device according to the embodiment of the present invention has been described above, the present invention is not limited to the embodiment described above, and various design modifications are possible within the scope of the claims. In addition, all or part of the technology of the medical device according to the embodiment of the present invention described above can be applied to the tip portion of an endoscope or the lens portion of an endoscope. [Explanation of symbols]

[0045] 1 Medical Devices 2. Capsule endoscopy 21 Permanent magnets 22 Outer shell 22a Anterior part 22b Projection part 22c Pressure Gauge 22d Biosensor 22da uneven part 22daa Recess 22db foundation part 23 Light irradiation unit 23a Measurement light irradiator 23aa uneven part 23aaa Recess 23ab basic part 24 Imaging unit 25 Communications Department 3. Control device 3x, 3x' x-axis coil 3y, 3y' y-axis coil 3z, 3z' z-axis coil 31 Communication device 32 Control Processor 32a CPU 32b Program memory section 32c Work memory section 32d Interface section PE Inspector WA: In vivo tissue surface

Claims

1. a capsule endoscope having a permanent magnet that generates power when a magnetic field is applied thereto and an outer shell that can contact or approach a surface of biological tissue inside a living body by the power, the capsule endoscope having a light irradiation unit, an imaging unit, and a communication unit inside the outer shell; a control device capable of generating the magnetic field to control the three-dimensional movement, orientation and position of the capsule endoscope and communicating with the communication unit of the capsule endoscope; Equipped with A medical device that measures the physical characteristics of the surface of the biological tissue when the outer shell of the capsule endoscope comes into contact with the surface of the biological tissue and applies force to the surface of the biological tissue, or the optical characteristics of a biosensor when the outer shell of the capsule endoscope has a biosensor and the biosensor comes into contact with the surface of the biological tissue, or the optical characteristics of reflected light when the outer shell of the capsule endoscope approaches the surface of the biological tissue and the light irradiation unit irradiates light onto the surface of the biological tissue.

2. 10. The medical device of claim 1, The physical property is an elastic property or a hysteresis property of the biological tissue surface, and is obtained by measuring a depression of the biological tissue surface while the shell applies the force having a component in a perpendicular direction to the biological tissue surface, or The physical property is a friction property of the surface of the biological tissue, and the medical device measures the force exerted by the outer shell on the surface of the biological tissue in a direction parallel to the surface of the biological tissue, thereby measuring the force that causes the capsule endoscope to start moving.

3. 10. The medical device of claim 1, The biosensor of the outer shell has a periodic structure including a recognition element and a concave-convex portion formed on the outer surface thereof, The optical characteristics are measured by irradiating measurement light from the light irradiation unit to the biosensor, and fluorescence, light absorption, scattering, or diffraction may occur in the uneven portion depending on the surface of the biological tissue that comes into contact with the uneven portion, and the optical characteristics are measured by receiving the reflected light from the uneven portion in the imaging unit.

4. 10. The medical device of claim 1, The light irradiating unit has a measurement light irradiator having a surface formed with concave and convex portions having a periodic structure smaller than the wavelength of light, and the medical device receives and measures the reflected light when the measurement light irradiator irradiates light onto the surface of the biological tissue.

Images