JP5259340B2 - Medical equipment - Google Patents

Description

  The present invention relates to a medical device that calculates the shape of an insert and the amount of twist using a plurality of detection units arranged in the insert to be inserted into a subject.

  As a method for confirming the shape of, for example, an insertion portion of an endoscope that is inserted into the body of a subject, Japanese Patent Laid-Open Nos. 6-261858 and 2007-130151, a strain sensor is provided in the insertion portion. And the method of confirming the shape of an insertion part is disclosed. Japanese Patent Application Publication No. 2003-515104 and Japanese Patent Application Laid-Open No. 2004-251799 disclose that an optical fiber Bragg Grating (hereinafter referred to as “FBG”) sensor is used to detect distortion of an insertion portion. A method for confirming the shape of the insertion portion is disclosed.

  Here, when the surgeon inserts the proximal end portion of the insertion portion while twisting, due to the contact resistance between the insertion portion and the lumen wall, the twisting operation of the proximal end portion is not completely transmitted to the distal end portion, A “twist”, in other words, a “twist” may occur in the elongated insertion portion. Excessive “twisting” of the insertion part not only changes the vertical and horizontal directions of the endoscopic image displayed on the monitor, but may also deform the lumen of the inserted living body.

In Japanese Patent Laid-Open No. 2003-38492, even when the component rotated at hand is not correctly transmitted to the tip, the bending detection optical fiber detects the twist angle component in the middle, so that the position of the tip is almost the same. An ultrasonic endoscope apparatus that can detect correctly is disclosed. However, since the bending detection optical fiber detects both bending and distortion caused by twisting, it is difficult to detect an accurate twisting angle.
JP-A-6-261858 JP2007-130151 Special table 2003-515104 gazette Japanese Patent Application Laid-Open No. 2004-251779 JP 2003-38492 A

  An object of the medical device of the present invention is to calculate the shape of the insert and the amount of twist, and to estimate a more accurate shape by calculating the amount of twist.

  In order to achieve the above object, a medical device according to the present invention is provided in an insert that is inserted into a subject, and includes a plurality of first detection units that detect bending distortion of the insert, Based on detection results of the plurality of first detection units and the plurality of second detection units, a composite probe having a plurality of second detection units for detecting torsional distortion, the shape of the insert, And a calculation unit for calculating the amount of twist.

  The present invention provides a medical device that calculates the shape of an insert and the amount of twist.

<First Embodiment>
Hereinafter, a medical device 1 according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory diagram for explaining a state in which the medical device of the present embodiment is used, and FIG. 2 is an explanatory diagram of the medical device of the present embodiment.

  The medical device 1 according to the first embodiment shown in FIG. 1 detects the shape and twist amount of the insertion portion 12 of the endoscope of the endoscope system 10 by using the optical fiber Bragg grating sensor unit 3. .

  Fiber Bragg Grating (hereinafter referred to as “FBG”) The sensor unit 3 is formed by forming a grating unit whose refractive index changes in the core of the optical fiber. Reflects light of a predetermined wavelength. This specific wavelength is referred to as a Bragg wavelength. And the FBG sensor part 3 has the characteristic that the wavelength of reflected light will change from a Bragg wavelength if there exists expansion-contraction in the longitudinal direction of a grating part. For this reason, the FBG sensor unit 3 is used for temperature measurement, strain measurement, or the like.

  In an optical frequency domain reflectometry multiplex (OFDR) type sensor probe in which a plurality of FBG sensor units 3 having the same Bragg wavelength are formed in one optical fiber, reflection from a reflector which is a total reflection terminal is performed. By causing the light and the reflected light from the sensor probe to interfere with each other, it is possible to detect how much each FBG sensor unit 3 has been deformed, in other words, how much distortion has occurred. For this reason, the OFDR sensor probe is used, for example, as a strain detection sensor for an elongated object to be detected.

  An endoscope system 10 is a medical instrument that is inserted into a subject 11 that is a subject to perform observation or treatment, and an endoscope insertion portion 12 that is an elongated insertion body, and an operation for operating the insertion portion 12. An operation unit 13, a main body unit 15 that performs control and image processing of the entire endoscope system 10, and a monitor 14 that displays an endoscopic image and the like.

From the treatment instrument hole 13A, which is an opening disposed in the vicinity of the operation part 13 on the base end part PE (Proximal End) side of the channel passing through the inside of the insertion part 12, the inside of the channel 12A (not shown) is passed through the distal end part DE (not shown) It is inserted to the (Distal End) side and arranged so as to be deformed into the same shape as the insertion portion 12. The composite probe 2 may be disposed on the insertion portion 12 so long as it is loosely fixed as long as the shape of the insertion portion 12 and the shape of the composite probe 2 coincide with each other to the extent that there is no practical problem. For example, as described above, it may be loosely fixed by being inserted into the channel, or may be incorporated in the insertion portion 12 in advance.

  The composite probe 2 of the medical device 1 includes three first sensor probes 2A, 2B, 2C and three first sensor probes 2A, 2B each having the FBG sensor portion 3 formed at the same position in the axial direction. 2C and the 2nd sensor probe 2D in which the FBG sensor part 3 wound spirally was formed. That is, in the medical device 1 of the present embodiment, the first detection unit that detects bending distortion and the second detection unit that detects torsional distortion are the same FBG sensor unit 3, but different distortions are detected depending on the arrangement. To do.

  The display unit of the medical device 1 is also used by the monitor 14 of the endoscope system 10, and the monitor 14 displays the shape of the composite probe 2, that is, the shape of the insertion portion 12 on the same screen as the endoscopic image. It has a display area 14A. The composite probe 2 may be incorporated in the insertion portion 12 instead of being inserted into the channel 12A.

  First, “twist” will be described with reference to FIG. When one end of an elongated elastic body is fixed and a couple is applied to the other end and rotated by a certain angle, the deformation appears in the elastic body. While the insertion portion 12 is being inserted into the lumen of the subject 11, even if the operator rotates the proximal end PE side, the rotational movement is caused to the distal end DE side due to friction between the lumen wall and the insertion portion. It is not transmitted completely, and the insertion portion 12 is twisted.

  In the case of a cylindrical shape having a length L, a diameter d, and a radius r shown in FIG. 3, the twist amount when the other end B0 is rotated by an angle γ with the one end B1 fixed is the twist angle γ. Can show.

And in FIG.
Since γ≈0, tan γ = γ
Therefore, B0B1 = L × tan γ = γL
On the other hand, B0B1 = π × d × (φ / 2π) = (d / 2) φ
From the above two formulas, γL = (d / 2) φ
Therefore, γ = (d / 2) (φ / L)
Here, assuming that the twist angle per unit length is θ, (d / 2) = r, (φ / L) = θ
Therefore, γ = rθ.

  The torsional stress becomes maximum at the outer periphery, but the above equation is not limited to the outer periphery of the cylinder, but also holds in the inner space of the cylinder. In other words, the composite probe 2 disposed inside the insertion portion 12 is also established.

  Next, the composite probe 2 will be described with reference to FIGS. 4 and 5. 4 is a perspective explanatory view of the composite probe of the medical device of the present embodiment, FIG. 5 is an explanatory view of the internal structure of the composite probe of the medical device of the present embodiment, and FIG. It is a cross-section figure of the VB-VB line of (A).

  As shown in FIG. 4, the composite probe 2 has a structure in which the first sensor probes 2A, 2B, and 2C are bundled through the resin 2P and the second sensor probe 2D is wound around. . That is, as shown in FIG. 5, in the composite probe 2, three first sensor probes 2A, 2B, and 2C are bundled around the metal wire 2M via the resin 2P, and the first probe along the outer periphery thereof. Two sensor probes 2D are wound. The composite probe 2 has flexibility. As shown in FIG. 2, each of the first sensor probes 2 </ b> A, 2 </ b> B, and 2 </ b> C is formed with an FBG sensor unit 3 at the same position in the axial direction. In the composite probe 2, since the three FBG sensor units 3 are at the same position, the displacement in the three-axis direction of the portion of the insertion unit 12 where the three FBG sensor units 3 are disposed can be measured. . The composite probe 2 detects torsional distortion in both compression and extension directions, in other words, torsional distortion in both the clockwise and counterclockwise directions, by the second sensor probe 2D having a spiral shape.

  Next, FIG. 6 is an overall configuration diagram illustrating an overall configuration of the medical device according to the present embodiment, and FIG. 7 is a partial configuration diagram illustrating a partial configuration of the medical device according to the present embodiment.

  As shown in FIG. 6, the medical device 1 includes a composite probe 2, a light source 6 that emits broadband light disposed in the main body portion 15, light emitted from the light source 6 by the composite probe 2, and reflection means. It is an optical component that is a light splitting means for splitting to be supplied to a certain reflector 5 and is also an interference means for causing the light reflected from the reflector 5 to interfere with the light reflected by the FBG sensor portion 3 of the composite probe 2. And a coupler 7. That is, the light splitting means and the interference means are constituted by the coupler 7 which is one optical component. The optical switch 7B supplies light to the four sensor probes 2A, 2B, 2C, and 2D in time series.

  In addition, the medical device 1 includes a light detection unit 8 that is a light detection unit that converts the interference light into an electrical signal by the coupler 7 and detects the signal, and a wavelength shift amount of each FBG sensor unit 3 from the signal detected by the light detection unit 8 ( The difference between the wavelength when there is no deformation of the portion where the FBG sensor unit 3 is present and the wavelength when there is deformation) is calculated, and the deformation amount of the FBG sensor unit 3 is obtained from the calculated wavelength shift amount. The calculation unit 9 </ b> A is a calculation unit that calculates the shape of the composite probe 2 and the amount of twist from the deformation amount of the sensor unit 3, and the control unit 9 </ b> B that controls the entire medical device 1.

  As shown in FIG. 7, in the medical device 1, the calculation unit 9A includes a coordinate calculation unit 9C that is a coordinate calculation unit, and a shape calculation unit 9F that is a shape calculation unit that calculates a shape and a twist amount. The shape of the insertion portion 12 and the amount of twist are displayed on the monitor 14. The surgeon performs an operation or the like for changing the shape display form of the insertion unit 12 from the input unit 17 serving as an input unit.

  Here, the operation principle of the FBG sensor will be described with reference to FIGS. As shown in FIG. 8, the FBG sensor unit 3 is a diffraction grating (grating) in which the refractive index of the core unit 4 </ b> A periodically changes over a predetermined length (for example, 5 mm) of the optical fiber 4. By irradiating the core portion 4A doped with germanium with ultraviolet rays through a mask, the refractive index slightly increases due to the photorefractive effect. The FBG sensor unit 3 is obtained by forming a portion (grating) having a high refractive index periodically in the axial direction by utilizing this. In FIG. 8 and the like, the number of gratings and the grating width with respect to the axial direction of the core are different from the actual FBG sensor so that the structure can be easily understood.

As shown in FIG. 9, the FBG sensor unit 3 only receives light having a Bragg wavelength λB, which is a predetermined wavelength represented by the following formula among incident light, depending on the interval d of the diffraction grating, in other words, the period. To reflect.
λB = 2 × n × d
Here, n is an effective refractive index of the core portion 4A.

  For example, when the effective refractive index n of the core portion 4A is 1.45 and the Bragg wavelength λB is 1550 nm, the distance d between the diffraction gratings is about 0.53 μm.

  FIG. 9 is an explanatory diagram for explaining the operation of the FBG sensor unit. FIG. 9A is a diagram showing the intensity of light with respect to the wavelength λ of incident light, and the incident light has a predetermined wavelength width, That is, it has a band. FIG. 9B shows the intensity of light with respect to the wavelength λ of the reflected light reflected by the FBG sensor unit 3, and the reflected light is light with a Bragg wavelength λB. FIG. 9C is a diagram illustrating the intensity of light with respect to the wavelength λ of incident light that has passed through the FBG sensor unit 3, and the transmitted light does not include the Bragg wavelength λB component reflected by the FBG sensor unit 3.

  As apparent from the above formula, when the FBG sensor unit 3 extends, the distance d between the diffraction gratings also increases, so that the Bragg wavelength λB moves to the long wavelength side. On the contrary, when the FBG sensor unit 3 is contracted, the distance d of the diffraction grating is also reduced, so that the Bragg wavelength λB moves to the short wavelength side. For this reason, the FBG sensor unit 3 can be used as a sensor for detecting temperature or external force. In this embodiment, the deflection amount of the composite probe 2, that is, the amount of bending deformation in the axial direction, or the amount of twist. Is detected.

  In the optical frequency domain reflectometry multiplexing (OFDR) system, interference light is formed from the reflected light from the FBG sensor unit 3 and the reflected light from the reflector 5, so that a plurality of FBG sensor units 3 are formed in one sensor probe. Even if formed, the deformation amount of each FBG sensor unit 3 can be detected.

  Next, processing performed by the calculation unit 9A will be described with reference to FIGS. FIG. 10 is an explanatory diagram for explaining a coordinate system in the composite probe 2 of the medical device, and FIG. 11 is an explanatory diagram for explaining processing of the calculation unit of the medical device.

  As shown in FIG. 10, the FBG sensor portions 3 formed on the three first sensor probes 2 </ b> A to 2 </ b> C are formed at equal intervals in the axial direction, for example, at an interval of 2 cm. The three FBG sensor portions 3 of the sensor probes 2A to 2C are disposed in the insert in a state where they are present at the same position in the axial direction. As shown in FIG. 10, simply “the position of the FBG sensor unit 3” means the center position of the three FBG sensor units 3 arranged at the same position in the axial direction.

  First, the coordinate calculation unit 9C of the calculation unit 9A is based on the detection result of the FBG sensor unit 3 and is positioned at the same position with respect to the position S of any FBG sensor unit 3, more precisely with respect to the axial direction of the composite probe 2. The first three-dimensional coordinates of the respective FBG sensor units 3 are calculated in the first three-dimensional coordinate system having the center position of the three arranged FBG sensor units 3 as the origin.

Coordinate calculation section 9C, for example, the most proximal end PE 3 single FBG sensor section formed at a position of the side _3A1 1 of the composite probe _2, 3A2 1, 3A3 first three-dimensional _one-center position S1 with the origin set the XYZ1 coordinate system is a coordinate system, the FBG sensor section _{3A1 1,} 3A2 _1, 3A3 1 of the three FBG sensor portion adjacent the deformation amount _{3A1 2,} 3A2 _2, 3A3 2 of the center position S2 _(x 2, y ₂ , z ₂ ) and direction (vx ₂ , vy ₂ , vz ₂ ) are calculated by the calculation unit 9A.

Coordinate calculation section 9C further, since the FBG sensor section _{3A1 2,} 3A2 _2, 3A3 2 of the center position _S2, the calculated _{(x 2, y 2, z} 2) and orientation _{(vx 2, vy 2, vz} 2), a transformation matrix _T ^{1 2} of the following three FBG sensor sections 33A1 _{3, 3A2} 3, 3A3 ₃ coordinate system XYZ ₂ to the center position S3 with the origin criteria is calculated using the following (equation 1).

ただし、ｒ_ｉｊ（ｉ＝１、２、３ ： ｊ＝１、２、３）は座標系ＸＹＺ１から座標系ＸＹＺ_２への回転（座標系ＸＹＺ_２のＺ軸と向き（ｖｘ_２、ｖｙ_２、ｖｚ_２）から回転行列を算出）、ｔｘ、ｔｙ、ｔｚは平行移動（位置（ｘ_２、ｙ_２、ｚ_２）と同じ）を表す。 (Formula 1)

_{However, r ij (i = 1,2,3:} j = 1,2,3) is the Z axis direction of the rotation of the coordinate system XYZ1 to the coordinate system XYZ ₂ (coordinate system _{XYZ 2 (vx 2, vy 2} , vz ₂ ) to calculate a rotation matrix), tx, ty, and tz represent translation (same as position (x ₂ , y ₂ , z ₂ )).

Similarly, three FBG sensor sections _3A1 3 present beside the coordinate system XYZ _2, which is _set, 3A2 3, 3A3 ₃ of the center position _{S3 (x 3, y 3,} z 3) and orientation _(vx 3, vy ₃ , Vz ₃ ) is calculated by the coordinate calculation unit 9C to calculate the transformation matrix T. The coordinate calculation section 9C repeating the same processing, ultimately, the tip of the three closest to DE FBG sensor section _{3A1 n,} 3A2 _n, 3A3 n of the center position _{Sn (x n, y n,} z n) and orientation _{(vx n, vy n, vz} n) and obtaining the transformation matrix ^{T _{n n-1.}}

Then, the coordinate calculation unit 9C converts the center position S of each of the three FBG sensor units 3 into the coordinate system XYZ1 using the conversion matrix. For example, three of the FBG sensor section _{3A1 i, 3A2 i, 3A3 i} 3 single FBG sensor section the center position Si in the coordinate system as a reference for the _{3A1 i + 1, 3A2 i +} 1, 3A3 i + 1 of the center position _{Si + 1 (x i + 1} , y _{i + 1} , z _{i + 1} ) and orientation (vx _{i + 1} , vy _{i + 1} , vz _{i + 1} ), the (x ^w _{i + 1} , y ^w _{i + 1,} z ^w _{i + 1} ) position in the XYZ1 coordinate system is as follows: (Equation 2).

座標算出部９Ｃは同様にすべての位置の３つのＦＢＧセンサ部３の中心位置ＳをＸＹＺ１座標系に変換し、形状算出部９Ｆは変換された座標を接続し補間処理等を行うことにより複合プローブ２の３次元形状、すなわち、複合プローブ２が配設された挿入部１２の３次元形状を算出する。 (Formula 2)

Similarly, the coordinate calculation unit 9C converts the center position S of the three FBG sensor units 3 at all positions into the XYZ1 coordinate system, and the shape calculation unit 9F connects the converted coordinates and performs interpolation processing, etc. 2, that is, the three-dimensional shape of the insertion portion 12 in which the composite probe 2 is disposed is calculated.

  Furthermore, the calculation unit 9A of the medical device 1 calculates torsional distortion from the deformation amount of the second sensor probe 2D. Since the second sensor probe 2D is compressed in the case of torsional distortion in the same direction as the winding direction, the Bragg wavelength λB is shifted to the short wavelength side, and in the case of torsional distortion in the direction opposite to the winding direction. Therefore, the Bragg wavelength λB is shifted to the long wavelength side. The second sensor probe 2D is further deformed by the influence of the bending strain of the insertion portion 12, and the deformation amount due to the bending strain is calculated by the first sensor probes 2A to 2C. Therefore, the calculation unit 9A can calculate only the deformation amount due to torsional distortion by excluding the deformation amount due to bending distortion from the deformation amount of the second sensor probe 2D.

  The calculating unit 9A calculates the relationship between the deformation amount due to torsional distortion and the torsional amount γ by actual measurement, and stores it in a memory unit (not shown) as a numerical table or a calculation formula.

  The medical device 1 according to the present embodiment calculates not only the shape of the insertion portion 12 but also the twist amount γ and displays it on the monitor 14. For this reason, the surgeon can know whether or not the insertion portion 12 is twisted by a twisting operation, and thus can perform a more appropriate operation.

In addition, the surgeon can perform a more appropriate operation by correcting the two-dimensional shape of the insertion portion 12 and displaying it on the monitor 14 in consideration of the amount of twist. The correction may be performed by applying a rotation matrix to the transformation matrix T ⁿ _n-1 by twisting.

  The twist amount γ may be displayed by displaying the twist angle between the base end portion PE and the distal end portion DE on the monitor 14 with a number, or superimposing it on the curve of the insertion portion 12 displayed on the monitor 14. Alternatively, the color corresponding to the amount of twist may be displayed, and the color at which part and how much twist is generated may be displayed.

  Further, the medical device 1 has the twist amount γ or the change amount of the twist amount calculated by the calculation unit 9A exceeding the threshold value based on the threshold value of the twist amount γ input and set in advance via the input unit 17 or the like. In such a case, the control unit 9B may generate a warning signal. In the medical device 1, a warning is displayed on the monitor 14 by a warning signal generated by the control unit 9B, or a warning sound or vibration is generated by a warning generating means (not shown), so the surgeon deforms the lumen. Such a large and rapid twisting operation is not performed.

  Further, in the medical device 1, based on the twist amount γ calculated by the calculation unit 9A, the control unit 9B and the like rotate the endoscopic image displayed on the monitor 14, and always display them in the same vertical and horizontal relationship. May be.

  Instead of the sensor probe having the FBG sensor unit 3, a sensor probe having a strain detection unit such as a strain cage may be used to detect deformation of each part of the insertion unit 12.

  In the medical device 1 of the present embodiment, the three first sensor probes 2A, 2B, and 2C are used to measure the three-dimensional shape of the insertion portion 12, but the number is three or more. Good. For example, four first sensor probes may be used to improve measurement accuracy. Further, in order to measure a longer range, for example, the number of first sensor probes that is a multiple of 3 may be used. That is, a composite probe in which a plurality of sets of three first sensor probes are used and the region where the FBG sensor unit 3 is formed is shifted and disposed in the longitudinal direction of the insertion unit 12 may be used.

  Furthermore, in the medical device 1 of the present embodiment, it is also possible to use a wavelength division multiplexing (WDM) type sensor probe.

<Second Embodiment>
Hereinafter, a medical device 1B according to a second embodiment of the present invention will be described with reference to the drawings. Since the configuration and operation of the medical device 1B are similar to those of the medical device 1 of the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.
FIG. 12 is a configuration diagram of the medical device of the second embodiment, FIG. 13 is an explanatory diagram of the internal structure of the composite probe of the medical device of the second embodiment, and FIG. FIG. 13 is a cross-sectional structure view taken along line XIIIB-XIIIB in FIG.

  As shown in FIGS. 12 and 13, the composite probe 62 of the medical device 1 </ b> B of the present embodiment is housed in a sheath 61 formed of a mesh tube and integrated with the three first sensor probes 2 </ b> A. 2B, 2C, and the second sensor probe 2D not housed in the sheath 61. The FBG sensor portions 3 of the first sensor probes 2A, 2B, 2C and the second sensor probe 2D are formed at the same position in the axial direction.

  The FBG sensor unit 3 of the first sensor probes 2A, 2B, and 2C is a first detection unit that detects bending distortion, and the FBG sensor unit 3 of the second sensor probe 2D detects second torsional distortion. It is a detection part. The FBG sensor unit 3 of the second sensor probe 2D is also deformed by bending strain. However, as described in the medical device 1 of the first embodiment, the calculation unit 9A is configured to deform the second sensor probe 2D. By removing the amount of deformation due to bending strain from the amount, only the amount of deformation due to torsional strain can be calculated.

  As the sheath 61, an example of a liner blade tube in which a liner tube in which a flat plate of stainless steel is wound in a spiral shape is covered with a net-like SUS wire is shown. Good. A hollow flexible shaft in which a left-handed and right-handed winding is wound around a hollow core wire over several layers may be used. The sensor probes 2A, 2B, and 2C may be integrated with an adhesive, and the integrated probe may be fixed only at both ends of the sheath 61. Further, the composite probe 62 is ideally placed in the center as much as possible according to the principle shown in FIG.

  In addition to the effects of the medical device 1 according to the first embodiment, the medical device 1B according to the present embodiment can be easily manufactured because the sensor probe 2D need not be arranged in a spiral shape. In addition, there is an advantage that the strength of the composite probe 62 is increased.

<Third Embodiment>
Hereinafter, a medical device 1C according to a third embodiment of the present invention will be described with reference to the drawings. Since the configuration and operation of the medical device 1C are similar to those of the medical device 1 according to the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.
FIG. 14 is a configuration diagram of a medical device according to the third embodiment, and FIGS. 15, 16, and 17 are explanatory diagrams of sensors that detect torsional distortion of the medical device according to the third embodiment.

  As shown in FIG. 14, the composite probe 72 of the medical device 1C of the present embodiment is in the same axial position as the three FBG sensor portions 3 of the first sensor probes 2A, 2B, and 2C formed. A sensor 71 serving as a second detection unit that detects torsional distortion is provided. The sensor 71 is an electrical sensor, and is, for example, one of the gyro sensor 71A and the acceleration sensor 71B, or the magnetic field sensor 71C.

As shown in FIG. 15, in the medical device 1 </ b> C using the gyro sensor 71 </ b> A and the acceleration sensor 71 </ b> B as the sensor 71, the gravity direction of the portion of the composite probe 72 in which each sensor 71 is disposed by each acceleration sensor 71 </ b> B. By detecting 73, the calculation unit 9A calculates the initial angle θ ₀ of each part of the composite probe 72.

Here, when the output of the acceleration sensor 71B is A and the gravitational acceleration is g, the initial angle θ ₀ is calculated as follows.

0 = A− (sin θ ₀ ) × g
θ ₀ = sin ⁻¹ (A / g)
Then, when the gyro sensor 71A detects the rotation amount from the initial angle θ ₀ of the insertion unit 12, the calculation unit 9A calculates the rotation amount of the portion of the composite probe 72 in which each sensor 71 is disposed. To do.

That is, the angle θ with respect to the horizontal plane of the portion of the composite probe 72 where the sensor 71 is disposed at a certain time point shown in FIG. 16 is calculated by integrating the output ω of the gyro sensor 71A as follows.
θ = ∫ωdt + θ ₀
In the same manner as described above, the calculation unit 9A includes three gyro sensors 71A1, 71A2, 71A3 for the X axis, the Y axis, and the Z axis, which are disposed at the respective positions of the composite probe 72. And the rotation angle with respect to the axial direction of the composite probe 72 is calculated from the outputs of the three acceleration sensors 71B1, 71B2, 71B3. Further, the twist amount γ of the entire insertion portion 12 is calculated from the angles θ of the plurality of sensors 71 of the composite probe 72.

  The medical device 1C according to the present embodiment can perform the same operation as the medical device 1 according to the first embodiment, and the sensor 71 calculates the torsion amount r under the condition that the sensor 71 is not completely affected by the bending strain. Is possible.

As shown in FIG. 17, in the medical device 1D using the magnetic field sensor 71C as the sensor 71, the calculation is performed by detecting the geomagnetic direction 74 of the portion of the composite probe 72 in which each magnetic field sensor 71C is disposed. The unit 9A calculates the angle θ of each part of the composite probe 72. That is, in the medical device 1D, the calculation unit 9A calculates the twist amount γ by detecting the rotation angle from the initial angle θ ₀ by the triaxial magnetic field sensor 71C using an MR sensor, a Hall element, a coil, or the like. To do.

  The medical device 1D of the present embodiment can not only achieve the same effect as the medical device 1C, but also the sensor 71 can more easily calculate the torsion amount r by using an absolute direction called a geomagnetic vector. It is possible.

  The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the scope of the present invention.

It is explanatory drawing for demonstrating the state which uses the medical device of 1st Embodiment. It is explanatory drawing of the medical device of 1st Embodiment. It is explanatory drawing for demonstrating a twist. It is an isometric view explanatory drawing of the compound probe of the medical equipment of a 1st embodiment. It is explanatory drawing of the internal structure of the composite probe of the medical device of 1st Embodiment. It is a whole lineblock diagram showing the whole medical device composition of a 1st embodiment. It is a partial block diagram which shows the structure of a part of medical device of 1st Embodiment. It is explanatory drawing for demonstrating the principle of operation of a FBG sensor. It is explanatory drawing for demonstrating the principle of operation of a FBG sensor. It is explanatory drawing for demonstrating the coordinate system in the composite probe of the medical device of 1st Embodiment. It is explanatory drawing for demonstrating the process of the calculation part of the medical device of 1st Embodiment. It is a block diagram which shows the structure of the medical device of 2nd Embodiment. It is explanatory drawing of the internal structure of the composite probe of the medical device of 2nd Embodiment. It is a block diagram which shows the structure of the medical device of 3rd Embodiment. It is explanatory drawing of the sensor which detects the torsion distortion of the medical device of 3rd Embodiment. It is explanatory drawing of the sensor which detects the torsion distortion of the medical device of 3rd Embodiment. It is explanatory drawing of the sensor which detects the torsion distortion of the medical device of 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1B, 1C, 1D ... Medical equipment 2, 62, 72 ... Composite probe 2A, 2B, 2C ... 1st sensor probe 2D ... 2nd sensor probe 2M ... Metal wire 2P ... Resin 3 ... Optical fiber Bragg grating sensor Unit 4 ... Optical fiber 4A ... Core unit 5 ... Reflector 6 ... Light source 7 ... Coupler 7B ... Optical switch 8 ... Light detection unit 9A ... Calculation unit 9B ... Control unit 9C ... Coordinate calculation unit 9F ... Shape calculation unit 10 ... Internal view Mirror system 11 ... Subject 12 ... Insertion part 12A ... Channel 13 ... Operation part 13A ... Treatment tool hole 14 ... Monitor 14A ... Display area 15 ... Main body part 17 ... Input part 61 ... Sheath 71 ... Sensor 71A ... Gyro sensor 71B ... Acceleration sensor 71C ... Magnetic field sensor 73 ... Gravitational direction 74 ... Geomagnetic direction

Claims (8)

A plurality of first detectors , each of which is arranged in the same position in the axial direction , are arranged on an insertion body to be inserted into the subject, and a plurality of first detection portions for detecting bending distortion of the insertion body . A composite probe comprising: one sensor probe; and a second sensor probe wound around the first sensor probe and formed with a plurality of second detection portions that detect torsional distortion of the insert. ,
And a calculation unit that calculates the shape of the insert and the amount of twist based on the detection results of the plurality of first detection units and the plurality of second detection units. Medical equipment. First sensor in which a plurality of first detector for detecting a bending strain of the insert is accommodated while being composed of three or more probes each formed axially same position, the sheath no screws Re deformed A composite probe comprising a probe and a second sensor probe formed with a plurality of second detection parts for detecting torsional distortion of the insert and not housed in the sheath ;
And a calculation unit that calculates the shape of the insert and the amount of twist based on the detection results of the plurality of first detection units and the plurality of second detection units. Medical equipment.   The medical device according to claim 2, wherein the sheath is configured by a mesh tube. A plurality of first detectors that are disposed in an insert that is inserted into the subject and that detect bending distortion of the insert; and a plurality of second detectors that detect torsional distortion of the insert. Having a composite probe;
Based on the detection results of the plurality of first detection units and the plurality of second detection units, the shape of the insert, and a calculation unit for calculating the amount of twist,
The composite probe is configured by one of a gyro sensor and an acceleration sensor, or a magnetic field sensor at the same position in the axial direction as the first detection portion of the three or more first sensor probes is formed. medical instrument you; and a second detector. The calculation unit calculates the shape by setting the center points of the three or more first detection units at the same position in the axial direction of the first sensor probe as detection unit positions. medical device according to any one of claims 1 to 4 to. The first sensor probe and the second sensor probe are optical fiber sensors in which a fiber Bragg grating sensor unit which is the first detection unit or the second detection unit is formed in an optical fiber,
The calculating unit is, the wavelength shift amount of the reflected light from the optical fiber sensor, distortion of the insert, and, from claim 1, characterized in that to calculate the amount of twist in any one of claims 5 The medical device described. The medical device according to any one of claims 1 to 6 , wherein the insertion body is an insertion portion of an endoscope. A plurality of first detectors that are disposed in an insert that is inserted into the subject and that detect bending distortion of the insert; and a plurality of second detectors that detect torsional distortion of the insert. Having a composite probe;
Based on the detection results of the plurality of first detection units and the plurality of second detection units, a calculation unit that calculates the shape of the insert and the amount of twist;
An input unit that inputs a threshold value of the twist amount; and a control unit that generates a warning signal when the twist amount or the change amount of the twist amount calculated by the calculation unit exceeds the threshold value. medical equipment you.

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