WO2019009279A1

WO2019009279A1 - Simulated biological sample, endoscope evaluation system, and endoscope evaluation method

Info

Publication number: WO2019009279A1
Application number: PCT/JP2018/025179
Authority: WO
Inventors: 裕基庄野; 成田　利治; 明日香向井; 遼佑伊藤
Original assignee: オリンパス株式会社
Priority date: 2017-07-04
Filing date: 2018-07-03
Publication date: 2019-01-10
Also published as: WO2019008679A1

Abstract

A simulated biological sample (1) comprises: a first member (2) that includes a fluorescent material and simulates the shape of biological tissue to be observed; and a second member (3) that covers the first member (2) and simulates the optical properties of tissue surrounding the biological tissue to be observed. The simulated biological sample (1) is for use in imaging performance evaluations of endoscopes. During such an imaging performance evaluation, first light and second light are shined, the first light including a wavelength that excites the fluorescent material and the second light not including an excitation wavelength.

Description

Living body simulation sample, endoscope evaluation system and endoscope evaluation method

The present invention relates to a biological simulation sample, an endoscope evaluation system and an endoscope evaluation method, and more particularly to a biological simulation sample for fluorescence observation, an endoscope evaluation system using the same, and an endoscope evaluation method.

Conventionally, a method of injecting a fluorescent dye such as indocyanine green (ICG) into a patient and measuring the fluorescence intensity from the fluorescent dye in blood is known as a means for determining the presence or absence of blood flow in living tissue. There is. In this method, a standard sample that emits fluorescence of known intensity is used to standardize the measured intensity of fluorescence (see, for example, Patent Documents 1 and 2).

JP 2005-300540 A JP, 2013-96920, A

However, the standard samples disclosed in

Patent Documents

1 and 2 are not suitable for use as simulated samples for performance evaluation and demonstration of endoscopes. That is, in the performance evaluation and demonstration of the endoscope, while using a simulated sample instead of the living tissue in the living body, the appearance of the fluorescence from the living tissue in the image acquired by the endoscope in the clinical scene is as real as possible It is required to reproduce in However, since the standard samples of

Patent Documents

1 and 2 do not simulate living tissue, they can not achieve a near-visible appearance of fluorescence from living tissue in a clinical setting.

The present invention has been made in view of the above-described circumstances, and is a biological simulation sample, an endoscope evaluation system, and an endoscope capable of achieving a near-visible appearance of fluorescence from living tissue in a clinical scene. The purpose is to provide an evaluation method.

In order to achieve the above object, the present invention provides the following means.
One aspect of the present invention is a first member containing a fluorescent material and simulating the shape of a living tissue to be observed, and a second member covering the first member and simulating the optical characteristics of the surrounding tissue of the living tissue to be observed And is used for evaluation of imaging performance of an endoscope, and in the imaging performance evaluation, a biological simulation in which the first light containing the excitation wavelength of the fluorescent material and the second light not containing the excitation wavelength are irradiated It is a sample.

According to this aspect, the shape of the living tissue to be observed is simulated by the first member, and the optical property of the peripheral tissue to be observed is simulated by the second member around the first member. Therefore, by irradiating the biological simulation sample with excitation light to cause the fluorescent material contained in the first member to emit light, it is possible to realize a near-visible appearance of fluorescence from biological tissue in a clinical situation.

In addition, such biological simulation samples can be used to accurately evaluate the imaging performance of the endoscope. That is, the endoscopic appearance of fluorescence from a living tissue is evaluated by observing the biological simulation sample with the endoscope while irradiating the biological simulation sample with the first light containing the excitation wavelength from the endoscope. be able to. On the other hand, an endoscope of a living tissue in a state not emitting fluorescence by observing the living body simulation sample with the endoscope while irradiating the living body simulation sample with the second light not containing the excitation wavelength from the endoscope You can assess the appearance of In addition, by selectively irradiating the first light and the second light to the living body simulation sample, the difference in the appearance of the living tissue when generating fluorescence and the living tissue when not generating fluorescence Can be evaluated.

In the above aspect, the second member has a layer structure in which two or more layers are stacked, and the two or more layers are different from each other in at least one of the light scattering property and the light absorption property. Good.
Such a second member more realistically simulates the optical characteristics of the surrounding tissue having a layered structure. This makes it possible to achieve a view closer to the view of the living tissue to be observed in the surrounding tissue having a layered structure.

In the above aspect, the first member may simulate the shape of a vessel, for example, the running shape of a blood vessel or the shape of a lymphatic vessel.
In this way, a closer view of fluorescence from vessels such as blood vessels or lymph vessels in a clinical setting can be realized by the first member simulating the shape of the vessel.

In the above aspect, the fluorescent material may be indocyanine green (ICG).
ICG is often used for fluorescence observation of vessels in the clinic. Therefore, a closer view of the fluorescence from vessels in a clinical setting can be achieved by the first member including the ICG.

In the above aspect, the first member is made of a gel material containing a fluorescent material, the second member is made of a cured resin material, and the first member is embedded in the second member. It is also good.
By using a gel material that can be shaped into any shape, various biological tissue shapes can be simulated by the first member. In addition, by embedding the gel material in a cured resin material that is stable against air and moisture, the gel material can be prevented from drying and the biological simulation sample can be stored for a long time.

In the above aspect, in the first image acquired by the endoscope under the irradiation of the first light, the contrast value of the first member with respect to the second member is 1% or more, and the second The contrast value of the first member relative to the second member may be less than 1% in the second image acquired by the endoscope under the light irradiation.
When the contrast value of the first image satisfies the above condition, it is possible to realize a closer appearance to the appearance of the fluorescence from the living tissue in the clinical scene. When the contrast value of the second image satisfies the above condition, it is possible to achieve a closer appearance to the appearance of a living tissue in a clinical scene.

In another aspect of the present invention, the biological simulation sample according to any of the above, the first light and the second light are alternatively irradiated to the biological simulation sample, and the irradiation of the first light is performed. An endoscope which acquires a first image below and acquires a second image under irradiation of the second light, and a display which displays the first image and the second image so as to be mutually contrastable. It is an endoscope evaluation system provided with a device.
According to this aspect, by comparing the first image and the second image displayed on the display device with each other, it is possible to perform between the irradiation of the first light and the irradiation of the second light. It is possible to evaluate the difference in the endoscopic appearance of fluorescence from living tissue.

In the above aspect, the display device includes an arithmetic device that calculates a contrast value of the first member with respect to the second member in each of the first image and the second image, and the display device An evaluation value for quantitatively evaluating the difference in the appearance of fluorescence from the biological tissue by the endoscope between the time of irradiation and the time of irradiation of the second light is displayed, and the evaluation value is the contrast value It may be a value based on

Another aspect of the present invention is a first imaging step of imaging the biological simulation sample while irradiating the biological simulation sample according to any of the above with the first light, and acquiring a first image; A second imaging step of imaging the biological simulation sample while irradiating the biological simulation sample with the second light and acquiring a second image; and based on the first image and the second image, An evaluation step of evaluating the difference in the appearance of the fluorescence from the living tissue of the observation object by the endoscope between the irradiation of the first light and the irradiation of the second light It is a mirror evaluation method.

In the above aspect, the method further includes an operation step of calculating a contrast value of the first member with respect to the second member in each of the first image and the second image, and in the evaluation step, based on the contrast value. A difference in the appearance of fluorescence from the living tissue by the endoscope may be evaluated.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in the ability to implement | achieve the appearance close | similar to the appearance of the fluorescence from the biological tissue in a clinical scene.

It is a perspective view of a living body simulation sample concerning one embodiment of the present invention. It is a side view of the biological simulation sample of FIG. 1A. It is a top view of the living body simulation sample which shows the modification of the shape of the 1st member of Drawing 1A. It is a top view of the living body simulation sample which shows the other modification of the shape of the 1st member of Drawing 1A. It is a perspective view of the modification of a living body simulation sample of Drawing 1A. It is a side view of a living body simulation sample of Drawing 4A. It is a perspective view of the other modification of the biological simulation sample of FIG. 1A. It is the schematic of the endoscope evaluation system which concerns on one Embodiment of this invention. It is a flowchart which shows the endoscope evaluation method which concerns on one Embodiment of this invention. It is a figure which shows the 1st image acquired in the endoscope evaluation method of FIG. It is a figure which shows the 2nd image acquired in the endoscope evaluation method of FIG. It is a flowchart which shows the endoscope evaluation method which concerns on other embodiment of this invention. It is a figure explaining the contrast value of the 1st image computed in the endoscope evaluation method of FIG. It is a figure explaining the contrast value of the 2nd image computed in the endoscope evaluation method of FIG.

Hereinafter, a biological simulation sample 1 according to an embodiment of the present invention will be described with reference to the drawings.
The living body simulation sample 1 according to the present embodiment is used as a subject instead of a living tissue in a living body in the evaluation and demonstration of the imaging performance of an endoscope. As shown in FIGS. 1A and 1B, the biological simulation sample 1 includes the first member 2 simulating the shape of the biological tissue to be observed, and the optical characteristics of the surrounding tissue of the biological tissue to be observed covering the first member 2 And a second member 3 that simulates.

The first member 2 is made of a gel material containing indocyanine green (ICG). As a gel material, for example, an agar gel, a gelatin gel, a two-component mixed gel, or the like is used. The first member 2 has a shape that simulates the traveling shape of a blood vessel to be observed. For example, the first member 2 has a branch structure in which branching from one linear structure to a plurality of linear structures is repeated. In FIG. 1A, the shape of the first member 2 is simplified.

The second member 3 is made of a block-like or sheet-like cured resin material, and the first member 2 is embedded in the second member 3. As the resin material, silicone resin, polyurethane resin, epoxy resin or the like is used. The second member 3 is the same as or similar to the surrounding tissue to be observed in at least one of the light absorption property and the light scattering property.

Such a biological simulation sample 1 is manufactured, for example, by the following method.
The gel material is uniformly mixed with ICG, the gel material is filled in a syringe, and the gel material is discharged in a thread form from the syringe, thereby forming the gel material into a shape that simulates the traveling shape of a blood vessel. Next, a liquid resin material is poured into a mold, the entire molded gel material is placed inside the resin material, and the resin material is cured. Thereby, the biological simulation sample 1 shown in FIG. 1A is manufactured.

Next, a method of using the biological simulation sample 1 configured as described above will be described.
The biological simulation sample 1 is disposed to face the tip of the endoscope, the excitation light (first light) is irradiated to the biological simulation sample 1 from the endoscope, and the fluorescence emitted from the ICG contained in the first member 2 (A wavelength of about 805 nm) is observed by an endoscope. The excitation light is light including a wavelength near the excitation wavelength 774 nm of the ICG. As a result, a first simulated image (first image) simulating an image obtained by imaging fluorescence from a blood vessel in the living body to which ICG is administered in a clinical scene is acquired by the endoscope. The first simulated image of the acquired biological simulation sample 1 is displayed on the display. The user evaluates the imaging performance of the endoscope in clinical use based on the first simulated image displayed on the display.

Further, the living body simulation sample 1 is irradiated with normal light (second light) from the endoscope 4, and reflected light of the normal light from the first member 2 and the second member 3 is observed by the endoscope. The ordinary light is light which does not include the excitation wavelength of ICG, and is, for example, white light. As a result, a second simulated image (second image) simulating an image of blood vessels in a living body under normal light irradiation in a clinical situation is acquired by the endoscope.

In this case, according to the present embodiment, since the first member 2 simulates the traveling shape of the blood vessel in the living body, in the living body simulation sample 1, fluorescence is emitted in the same shape as the traveling shape of the blood vessel. Furthermore, since the second member 3 around the first member 2 simulates the optical properties of the surrounding tissue of the blood vessel, the fluorescence emitted from the first member 2 is the same as in living tissue in the second member 3 Spread out. As a result, in the first simulated image (first image) of the biological simulation sample 1, a near-visible appearance of the fluorescence observed by the endoscope in the clinical scene is realized. Thus, the user can accurately evaluate the appearance of fluorescence in the image when the endoscope is used clinically based on the first simulated image on the display.
In addition, by comparing the first simulated image under the irradiation of the excitation light and the second simulated image under the irradiation of the normal light, an endoscope of the traveling shape of the blood vessel at the time of fluorescence observation and at the time of normal observation It is possible to evaluate the difference in appearance due to

In addition, since the first member 2 is made of a gel material that can be formed into an arbitrary shape, the shape of any living tissue including a living tissue having a complicated shape such as a traveling shape of a blood vessel Has the advantage of being able to simulate
In addition, although the gel material constituting the first member 2 is not suitable for long-term storage since the characteristics change due to drying etc., the cured resin material constituting the second member 3 is stable against air and moisture. Material and suitable for long-term storage. Therefore, covering the entire first member 2 with the second member 3 has an advantage of being able to provide the biological simulation sample 1 that can be stored for a long time while maintaining the quality of the fluorescent material.

In the present embodiment, the optical characteristics are such that the first member 2 and the second member 3 have a contrast value of 1% or more in the first simulated image and a contrast value of less than 1% in the second simulated image. It is preferable to have The contrast value is the contrast value of the first member 2 with respect to the second member 3 in each image, and is defined, for example, by the following equation (1). The contrast value is controlled, for example, by adjusting the concentration of ICG in the first member 2 and the light scattering / light absorption intensity of the second member 3.
Contrast value = (brightness of first member−brightness of second member) / (brightness of second member + brightness of first member) × 100 (1)
According to this configuration, it is possible to provide the user with the first simulated image and the second simulated image capable of more accurate evaluation of the appearance of fluorescence by the endoscope.

In the present embodiment, the first member 2 simulates the traveling shape of the blood vessel. However, instead of this, the shape of another living tissue may be simulated.
For example, as shown in FIG. 2, the first member 2 may simulate the shape of a lymphatic vessel and may simulate the shape of another vessel such as a bile duct. Alternatively, as shown in FIG. 3, the first member 2 may simulate the shape of a tumor.

In the present embodiment, ICG is used as the fluorescent material, but the type of fluorescent material is not limited to this, and other types of fluorescent materials may be used. For example, quantum dots or protoporphyrin IX (ppIX) may be used as the fluorescent material.
In the clinic, protoporphyrin IX (ppIX) is often used for fluorescent labeling of tumor tissue such as cancer. Therefore, it is preferable to use ppIX for the first member 2 that simulates the shape of the tumor in FIG. 3 so as to achieve a closer look to the fluorescence from the tumor in the clinical setting.

In the present embodiment, although the single first member 2 is disposed in the second member 3 having a single-layer structure, the number of first members 2 and the number of layers constituting the second member 3 Can be changed as appropriate.
For example, as shown in FIGS. 4A and 4B, the plurality of

first members

21 and 22 may be disposed at mutually different depths in the second member 3 having a single-layer structure. The shapes of the plurality of

first members

21 and 22 may be identical to each other, or may be different from each other as shown in FIG. 4A.

Further, as shown in FIG. 5, the second member 3 may have a layered structure in which two or

more layers

3 a and 3 b are stacked. The 2nd member 3 of 2 layer structure is shown by FIG. 5 as an example.
Surrounding tissues such as blood vessels, lymph vessels, and tumors have a layered structure composed of multiple layers having different light scattering properties and light absorption properties. The

layers

3a and 3b of the second member 3 are different from each other in at least one of the light scattering property and the light absorption property so as to simulate the optical property of each layer (for example, the mucous layer and muscle layer) of the surrounding tissue. . This makes it possible to achieve an appearance closer to the appearance of fluorescence from the observation target in a clinical setting.

Specifically, the

layer

3a, 3b have respectively about 0.1 mm ^-1 or more ^{5 mm -1} or less of the light scattering coefficient in the wavelength range of visible light. The

layers

3a and 3b have light absorption characteristics that simulate the absorption spectrum of blood, and each have a light absorption coefficient of more than about 0 mm ^-1 and 20 mm ^-1 or less in the visible light wavelength range. The light scattering coefficient and the light absorption coefficient of the layer 3b simulating the layer on the deep side are preferably larger than the light scattering coefficient and the light absorption coefficient of the layer 3a simulating the layer on the front surface, respectively.

When the second member 3 has a plurality of

layers

3a and 3b as shown in FIG. 5, the first member 2 may be disposed only in one layer, and is disposed between two adjacent layers. It may be provided, or may be disposed across multiple layers. Alternatively, the first member 2 may be disposed in each of the

layers

3a and 3b.

Next, an endoscope evaluation system 10 and an endoscope evaluation method according to an embodiment of the present invention will be described.
The endoscope evaluation system 10 according to the present embodiment is connected to the living body simulation sample 1, an optical endoscope 4 for observing the living body simulation sample 1, and the endoscope 4 as shown in FIG. 6. And a display (display device) 5. Reference numeral 6 is a control device connected to the endoscope 4 to control the endoscope 4.
The biological simulation sample 1 may be any of the biological simulation samples 1 shown in FIGS. 1A to 5.

The endoscope 4 selectively irradiates the biological simulation sample 1 with the first light including the ICG excitation wavelength (around 774 nm) and the second light not including the ICG excitation wavelength. For example, the endoscope 4 includes an excitation light source that emits excitation light and a white light source that emits white normal light. The endoscope 4 irradiates the biological simulation sample 1 with excitation light as a first light, and irradiates the biological simulation sample 1 with normal light as a second light. Switching between the first light and the second light is performed, for example, by turning on and off the excitation light source and the white light source. The first light may be monochromatic light or may be light including wavelengths other than the excitation wavelength. The second light may be monochromatic light instead of white light. The image acquired by the endoscope 4 is transmitted from the endoscope 4 to the display 5 and displayed on the display 5.

Next, an endoscope evaluation method by the endoscope evaluation system 10 will be described.
In the endoscope evaluation method according to the present embodiment, as shown in FIG. 7, step S1 of irradiating the first light from the endoscope 4 to the biological simulation sample 1 and the first light are irradiated. Step S2 of acquiring a first image of the biological simulation sample 1 by the endoscope 4, step S3 of irradiating the biological simulation sample 1 with the second light from the endoscope 4, and irradiation of the second light Step S4 of acquiring a second image of the living body simulation sample 1 by the endoscope 4 and step S5 of evaluating the imaging performance of the endoscope 4 based on the first image and the second image.

The first image acquired in step S2 is an image including the fluorescence of ICG from the first member 2 as shown in FIG. 8A. The second image acquired in step S4 is an image that does not contain or hardly contains ICG fluorescence, as shown in FIG. 8B.
In step S5, the first image and the second image are displayed on the display 5 in a mutually contrastable manner. For example, the first image and the second image are displayed in parallel on the display 5. The user can evaluate the endoscopic view of the fluorescence from the blood vessel based on the first image. In addition, the user compares the first image and the second image with each other to find out of the fluorescence from the blood vessels between the irradiation of the first light and the irradiation of the second light. The difference in the appearance by the endoscope 4 can be qualitatively evaluated.
Steps S1 and S2 may be performed after steps S3 and S4.

The endoscope evaluation system 10 may further include an arithmetic device that calculates the contrast value of each of the first image and the second image. The arithmetic device is, for example, a processor such as a central processing unit (CPU) incorporated in the control device 6. The arithmetic device processes the first image and the second image transmitted from the endoscope 4 to the control device 6 in accordance with a program stored in the storage device in the control device 6.

The computing device calculates the contrast value of the first member 2 with respect to the second member 3 in the first image. The computing device also calculates the contrast value of the first member 2 with respect to the second member 3 in the second image.
The calculation area A for calculating the contrast value is a one-dimensional area including both the first member 2 and the second member 3 as shown in FIGS. 8A and 8B. The calculation area A may be a two-dimensional area including both of the first member 2 and the second member 3. 10A and 10B show the brightness in the calculation area A of FIGS. 8A and 8B. The contrast value is calculated from the above equation (1) based on, for example, the brightness I1 of the first member 2 and the brightness I2 of the second member 3 in each image.

FIG. 9 shows an endoscope evaluation method by the endoscope evaluation system provided with a computing device. In the endoscope evaluation method of FIG. 9, in addition to steps S1 to S4, the comparison of step S6 for calculating the contrast value from the first image, step S7 for calculating the contrast value from the second image, and the contrast value And S 8 of evaluating the imaging performance of the endoscope 4 based on Steps S1 and S2 may be performed after steps S3 and S4.

In step S8, an evaluation value based on the contrast value of each of the first and second images is displayed on the display 5 in addition to or in place of the first and second images. The evaluation value is a value for quantitatively evaluating the difference in the appearance of the fluorescence from the blood vessel by the endoscope 4 between the irradiation time of the first light and the irradiation time of the second light. For example, the contrast values of the first image and the second image are displayed on the display 5 as they are. The user compares the two contrast values displayed on the display 5 with each other to obtain an endoscope of fluorescence from the blood vessels between the first light irradiation and the second light irradiation. The difference in appearance due to 4 can be quantitatively evaluated. The evaluation value may be another value, for example, the ratio of the contrast value of the first image to the contrast value of the second image.

DESCRIPTION OF SYMBOLS 1 Living

body simulation sample

2, 21, 22 1st member 3

2nd member

3a, 3b Layer 4 Endoscope 5 Display (display apparatus)
6 control device S1, S2 first imaging step S3, S4 second imaging step S5, S8 evaluation step S6, S7 operation step

Claims

A first member containing a fluorescent material and simulating the shape of a living tissue to be observed;
And a second member that covers the first member and simulates the optical characteristics of the surrounding tissue of the living tissue to be observed.
A biological simulation sample which is used for evaluation of imaging performance of an endoscope and in which the first light including the excitation wavelength of the fluorescent material and the second light not including the excitation wavelength are irradiated in the imaging performance evaluation.
The second member has a layer structure in which two or more layers are stacked,
The biological simulation sample according to claim 1, wherein the two or more layers differ from each other in at least one of light scattering properties and light absorption properties.
The biological simulation sample according to claim 1 or 2, wherein the first member simulates the shape of a vessel.
The biological simulation sample according to claim 3, wherein the first member simulates a traveling shape of a blood vessel or a shape of a lymphatic vessel.
The biological simulation sample according to any one of claims 1 to 4, wherein the fluorescent material is indocyanine green.
The first member is made of a gel material containing a fluorescent material,
The second member is made of a cured resin material,
The biological simulation sample according to any one of claims 1 to 5, wherein the first member is embedded in the second member.
In the first image acquired by the endoscope under the irradiation of the first light, the contrast value of the first member with respect to the second member is 1% or more.
The contrast value of the said 1st member with respect to the said 2nd member is less than 1% in the 2nd image acquired by the said endoscope under irradiation of the said 2nd light, The 1st item is either of 1 to 6 The biological simulation sample according to the above.
A biological simulation sample according to any one of claims 1 to 7;
The first light and the second light are alternatively irradiated to the biological simulation sample, a first image is obtained under the irradiation of the first light, and a second image is obtained under the irradiation of the second light. The endoscope which acquires 2 images,
A display device for displaying the first image and the second image so as to be contrastable with each other.
The arithmetic device for calculating the contrast value of the first member with respect to the second member in each of the first image and the second image,
An evaluation value for quantitatively evaluating the difference in the appearance of fluorescence from the living tissue by the endoscope between the time of the first light irradiation and the time of the second light irradiation by the display device The endoscope evaluation system according to claim 8, wherein the evaluation value is a value based on the contrast value.
The living body simulation sample according to any one of claims 1 to 7 is imaged by the endoscope while the living body simulation sample is irradiated with the first light from the endoscope, and a first image is obtained. A first imaging step to
A second imaging step of capturing an image of the biological simulation sample with the endoscope while irradiating the biological simulation sample with the second light from the endoscope; and acquiring a second image;
Based on the first image and the second image, from the biological tissue to be observed by the endoscope between the time of the irradiation of the first light and the time of the irradiation of the second light And an evaluation step for evaluating differences in the appearance of fluorescence.
Calculating the contrast value of the first member relative to the second member in each of the first image and the second image,
The endoscope evaluation method according to claim 10, wherein in the evaluation step, a difference in the appearance of fluorescence from the living tissue by the endoscope is evaluated based on the contrast value.