JP2007029416A - Position detection system of internal section - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position detection system of an internal body region which is highly safe for a human body and with which the desired position of the internal body region can be identified precisely and speedily. <P>SOLUTION: The system comprises: a light source part 2 for radiating near infrared rays; an insert-holding part 4 for insert-holding the desired internal body region; an imaging part 3 for receiving reflected light and/or scattered light by the insert-holding part 4 of the near infrared rays radiated from the light source part 2; a light-filtering part 6 which passes through the near infrared rays ranging 700nm to 1,300nm; and a polarization part 7 which transmits near infrared rays having polarization plane in a desired direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a system for detecting a desired position in the body, and more particularly, to detect the position of a body part by detecting reflected light and / or scattered light of a clip held by the body part using near infrared rays. About the system.

In general, when a lesion site such as a tumor generated inside a digestive organ such as the large intestine is excised, laparoscopic surgery is often performed with less burden on the patient compared to open surgery. In this surgical method, an endoscope may be inserted into the digestive organ before surgery, and the lesion site may be marked with a dye or a marking clip in advance. A lesion site is visually recognized from outside the digestive organ by being inserted and irradiated with light from the distal end of the endoscope, or the position of the marking clip is confirmed using an X-ray image.
However, in the method of reinserting the endoscope, the confirmation is unclear because it is visible from outside the digestive organ. For example, when the digestive organ is the large intestine, the gas used to widen the field of view of the endoscope The intestinal tract is expanded by the feeding, and the space between the intestinal wall and the intestine, which is a surgical field for laparoscopic surgery, is narrowed. Furthermore, since it takes time to insert the endoscope, there is a problem that the operation time becomes long, and as a result, the burden on the patient increases.
On the other hand, in the method of confirming the position of the marking clip by fluoroscopy, there is a problem that the patient and the surgeon are exposed to radiation by the X-ray, and the surgeon's behavior is restricted, which impedes rapid surgery. It was. In addition, with the method of injecting a dye and marking it, it is difficult to visually recognize the dye when the injection needle is stuck deeply into the digestive organ, and conversely, the risk of causing peritonitis when the injection needle penetrates deeply and penetrates the peritoneum However, there was a concern that the surgeon was asked for skill and the patient was burdened with extra burden.
Therefore, an apparatus for easily detecting the position of a lesion site in the body has been considered.

  For example, Patent Document 1 discloses a device related to a marking clip in which a luminous body is combined under the name of “shining marking clip”. In this device, a tumor or the like generated in a digestive organ or the like is disclosed. Since the marking clip that sandwiches the lesion site is combined with the illuminant, the marker clip that emits light from outside the gastrointestinal tract can be seen at the time of surgery, and re-insertion of the endoscope and X-ray images are used. The incision site can be determined without it.

Patent Document 2 discloses a first medical instrument such as an endoscope that is inserted into a biological duct under the name of “in-vivo position detection system” and a percutaneous device from outside the biological duct. Body cavity position having a second medical instrument such as a clip or grasping forceps inserted into the body cavity, and detection means for detecting the relative position of the first medical instrument and the second medical instrument An invention relating to a detection system is disclosed.
In the invention disclosed in Patent Document 2, a hall element is installed at the distal end of an endoscope, and a permanent magnet is installed in a treatment tool such as a clip or a grasping forceps. Since the Hall element provided at the distal end of the endoscope measures the magnetic field generated by the magnet, the relative position of the endoscope and the treatment instrument can be detected by a warning sound or the like. It is possible to accurately treat the position of a lesion site or the like found by an endoscope with a treatment tool.

Patent Document 3 discloses an invention relating to a digestive organ lesion site identification system that uses a magnetic sensor to identify the position of a lesion site by detecting a magnet attached to the lesion site under the name “digestive organ lesion site identification system”. Has been.
In the invention disclosed in Patent Document 3, prior to excision of a lesion site of the digestive organ, an endoscope is inserted into the digestive organ to check the lesion site, and a magnet is attached to the lesion site as a mark. Then, the endoscope is withdrawn from the digestive tract and the treatment is temporarily terminated. In the excision operation, the magnetic field attached to the lesion site in the digestive organ is detected from the outside of the digestive organ using a magnetic sensor, so that the magnet mounting position is accurately determined as the position of the digestive organ lesion site. It identifies quickly and enables surgery on the excision site in a short time with less burden on patients and surgeons.
Noto 3027808 JP-A-6-285042 JP 2002-159508 A

  However, in the conventional technique described in Patent Document 1, since the visual recognition is made through the digestive organ wall, the confirmation becomes unclear and there is a concern about placing the marking clip combined with the light emitter in the body. There was a problem that there was.

  Further, in the conventional technique described in Patent Document 2, since an operation such as excision is performed in a state where an endoscope having a detection means is inserted, it takes time to confirm a lesion site by the endoscope, Since the operation time of the patient becomes longer, there is a problem of placing a burden on the patient. In addition, since the field of view of the endoscope is enlarged, it becomes impossible to secure an intra-abdominal field of view as a surgical field, and there is a problem that it is not practical.

  In the conventional technique described in Patent Document 3, a magnet whose surface is treated with titanium or the like in consideration of the affinity with the human body is used in the indwelling of the magnet. Had the problem that concerns remained.

  The present invention has been made in response to such a conventional situation, and provides a body part position detection system that is highly safe for the human body and can accurately and quickly identify a desired position of the body part. Objective.

In order to achieve the above object, a body part position detection system according to claim 1 is a light source unit that emits near-infrared rays, a clamping unit that sandwiches a desired body part, and a near-infrared ray emitted from the light source unit. And an imaging unit that receives reflected light and / or scattered light from the sandwiching unit.
In the in-vivo part position detection system configured as described above, near infrared rays emitted from the light source part are reflected and / or scattered at the holding part that holds the desired internal part, and the reflected light and / or scattered light at the holding part is imaged. It has the effect of receiving light at the part.

The body part position detection system according to claim 2 includes a light source unit that emits near-infrared rays, a sandwiching unit that is coated with a near-infrared absorbing material on the surface and sandwiches a desired body part, and a light source unit. And an imaging unit that receives scattered light from the sandwiched portion of the emitted near-infrared light.
In the in-vivo part position detection system configured as described above, the near-infrared radiation emitted from the light source unit sandwiches the desired in-vivo part, and absorbs near-infrared rays and scatters in the sandwiching part on which the near-infrared absorbing material is applied, It has the effect | action that the scattered light in this clamping part is received in an imaging part.

The body part position detection system according to claim 3 is the body part position detection system according to claim 1 or 2, wherein the light source unit and / or the imaging unit is in a range of 700 nm to 1300 nm. A filtering part that transmits near-infrared rays is provided.
In the in-vivo part position detection system having the above configuration, in addition to the action of the invention according to claim 1 or 2, the filtering part transmits only near infrared rays in the range of 700 nm to 1300 nm. , Has the effect of emitting or receiving near infrared rays in a limited wavelength range.

Furthermore, the body part position detection system according to claim 4 is the body part position detection system according to any one of claims 1 to 3, wherein the light source unit and / or the imaging unit are desired. The polarizing part which permeate | transmits a near-infrared with a polarization plane in the direction of is provided.
In the in-vivo part position detection system having the above configuration, in addition to the operation of the invention according to any one of claims 1 to 3, the light source unit or the imaging unit is polarized in a desired direction transmitted by the polarization unit. It has the effect of emitting or receiving only near-infrared rays having a surface.

An internal body part position detection system according to a fifth aspect of the invention is the internal body part position detection system according to any one of claims 1 to 4, wherein the reflected light received by the imaging unit and / or Or it has an output part which displays the data about scattered light as an image, or outputs a signal.
In the body part position detection system with the above configuration, in addition to the operation of the invention according to any one of claims 1 to 4, the output unit relates to reflected light and / or scattered light received by the imaging unit. It has an effect of displaying data as an image or outputting a signal.

Finally, the body part position detection system according to claim 6 can read out data relating to reflected light and / or scattered light received by the imaging unit in the body part position detection system according to claim 5. And an analysis unit that reads data on reflected light and / or scattered light from the optical information storage unit and analyzes the frequency spectrum and / or luminance distribution of the reflected light and / or scattered light. Then, the output unit displays or outputs the data regarding the frequency spectrum and / or luminance distribution obtained by the analysis unit as an image.
In the body part position detection system having the above-described configuration, in addition to the operation of the invention described in claim 5, the optical information storage unit stores data related to reflected light and / or scattered light received by the imaging unit in a readable manner. The analysis unit reads the data on the reflected light and / or scattered light from the optical information storage unit and analyzes the frequency spectrum and / or luminance distribution of the reflected light and / or scattered light, and the output unit is obtained by the analyzing unit. The obtained frequency spectrum and / or luminance distribution data is displayed or output as an image.

  In the in-vivo part position detection system according to claim 1 of the present invention, the near-infrared reflected light and / or scattered light of the holding part held in the body is received by the imaging part, so that the position of the holding part, that is, the internal part The desired position can be detected accurately and quickly.

  In the body part position detection system according to claim 2 of the present invention, the near-infrared absorbing material is applied to the sandwiching portion, so that reflection of near-infrared light at the sandwiching portion is suppressed and only scattered light from the sandwiching portion is accurately detected. It is often possible to receive light at the imaging unit and detect the position of the internal body part.

  And in the body part position detection system according to claim 3 of the present invention, the light source unit and / or the imaging unit emits or receives light by removing near infrared rays other than the range of 700 nm to 1300 nm by the filtering unit. A wavelength having high biological permeability can be selected and used.

  Furthermore, in the body part position detection system according to claim 4 of the present invention, the light source unit and / or the imaging unit selects or emits or receives near-infrared light having a polarization plane in a desired direction by the polarizing unit. Near infrared rays having a polarization plane in an unnecessary direction can be easily removed.

  In the body part position detection system according to claim 5 of the present invention, the data relating to the reflected light and / or scattered light received by the imaging unit is displayed or output as an image by the output unit. Data relating to reflected light and / or scattered light can be easily viewed.

  Finally, in the in-vivo part position detection system according to claim 6 of the present invention, the user can read data on the reflected light and / or scattered light received by the imaging unit from the optical information storage unit as needed. In addition, the analysis unit can analyze the frequency spectrum and / or the luminance distribution for the read data regarding the reflected light and / or scattered light. Furthermore, the analysis result can be easily visually recognized at the output unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a body part position detection system according to the present invention will be described below with reference to FIGS.
FIG. 1 is a conceptual diagram of a body part position detection system according to the present embodiment of the present invention.
In FIG. 1, a body part position detection system 1 according to the present embodiment is mainly composed of a light source 2, a camera 3 and a marking clip 4. 5 When irradiating the marking clip 4 held at a desired position inside the mark 5, near-infrared reflection and scattering by the marking clip 4 locally increase in the place where the marking clip 4 exists. Light is received using a camera 3 such as a CCD camera having sensitivity to near-infrared light, and is picked up as an image, and the position of the marking clip 4, that is, the position of a body part is detected from the obtained image. .
As described above, the light source 2 emits safe near infrared rays to the human body, and includes the bandpass filter 6 and the polarization filter 7. The bandpass filter 6 transmits near infrared rays having a wavelength in the range of 700 nm to 1300 nm, and is emitted from the light source 2 and generally has a wavelength other than 700 nm to 1300 nm among the near infrared rays having a wavelength of 700 nm to 2 μm. The band-pass filter 6 removes the noise. Near-infrared rays in the range of 700 nm to 1300 nm have high biological permeability and can propagate up to several millimeters deep in the biological tissue 5, so that effective near-infrared rays can be selected by installing the bandpass filter 6.
The polarizing filter 7 transmits near infrared rays having a polarization plane in a specific direction. By installing the polarizing filter 7, only a near infrared ray having a polarization plane in a specific direction is marked. 4 can be irradiated.

As described above, the camera 3 also receives reflected light and scattered light from the marking clip 4 and captures them as an image. Note that the captured image includes information on luminance, frequency, and position. Further, similarly to the light source 2, a band pass filter 6 and a polarizing filter 7 are provided. In the polarizing filter 7, near infrared light having a polarization plane in a specific direction is selected, and the band pass filter 6 has a wavelength range of 700 nm to 1300 nm. The near-infrared light is selected to receive reflected light and scattered light that can pass through these two filters.
In the actual captured image by the camera 3, the reflected light due to the unevenness on the surface of the living tissue 5 greatly disturbs the contour of the image of the marking clip 4. Furthermore, since the reflected light from the surface of the living tissue 5 is very strong, the image of the marking clip 4 sandwiched in the deep part of the living tissue 5 becomes low in contrast due to the overlapping with the reflected light, making detection difficult. Therefore, a polarizing filter 7 is installed for the purpose of removing the surface reflection component of the living tissue 5. That is, when the near-infrared ray having a polarization plane in a specific direction selected is irradiated toward the marking clip 4 by the polarizing filter 7 on the light source 2 side, the polarization state is maintained in the reflected light on the surface of the living tissue 5. The surface reflected light of the living tissue 5 can be removed by the polarizing filter 7 on the camera 3 side. Therefore, by removing the surface reflected light of the living tissue 5, a clear image of the marking clip 4 can be acquired in the captured image.

  The marking clip 4 is made of metal, and a commonly used one can be used. Further, a near-infrared light absorbing material having high biocompatibility such as indocyanine green (hereinafter referred to as ICG) may be applied to the marking clip 4. In this case, since the near infrared ray irradiated from the light source 2 is absorbed by the marking clip 4, the scattered light from the marking clip 4 is reduced and received by the camera 3 to pick up an image. An image can be taken.

  This embodiment can be used, for example, in laparoscopic surgery. As in the conventional method, prior to the operation, if the marking clip 4 attached to the endoscope is held between the lesions in the digestive organs of the body, it is inserted into the abdominal wall 8 as shown in FIG. The reflected light and scattered light from the near-infrared marking clip 4 from the light source 2 is received by the camera 3 and captured as an image using the light source 2 and the camera 3, so that the position of the marking clip 4 can be accurately detected from outside the digestive organs. And it can be confirmed quickly. Therefore, the burden on the patient and the operator can be reduced from the reduction of the operation time. It is also effective to be able to diagnose a wide area at once.

Next, the system configuration for detecting the position of the body part according to the present embodiment will be described with reference to FIG.
FIG. 2 is a configuration diagram of the body part position detection system according to the present embodiment.
In FIG. 2, in the present embodiment, an amplifying unit 9, a database 10, an analyzing unit 11, and an output unit 12 are connected to the camera 3.
The amplifying unit 9 amplifies the intensity of the reflected light and scattered light received by the camera 3, and can be omitted if the intensity of the reflected light and scattered light can be sufficiently secured.
The database 10 stores data relating to reflected light and scattered light received and imaged by the camera 3 and can be read out as needed. The database 10 may store data related to reflected light and scattered light amplified by the amplifying unit 9 together with raw data related to reflected light and scattered light.

Next, the analysis unit 11 reads the data related to the reflected light and scattered light stored in the database 10 and analyzes the frequency spectrum and the luminance distribution for the reflected light and scattered light. Here, the frequency spectrum means an electromagnetic wave having a plurality of frequency components, in particular, near infrared rays in the present application, which are decomposed into frequency components and arranged in magnitudes for each frequency component. In addition, the luminance distribution means an electromagnetic wave having a plurality of luminance components, particularly near infrared rays in the present application, which is decomposed into luminance components and arranged in the size of each luminance component. Since frequency (m) = light speed (m / sec) / frequency (1 / sec) is established for frequency and wavelength, frequency and wavelength, and frequency spectrum and wavelength spectrum have the same meaning.
In other words, the analysis unit 11 can analyze the frequency and the luminance, and has a function of disassembling and arranging the data regarding the reflected light and scattered light stored in the database 10 for each frequency or luminance. Yes. It should be noted that the arrangement is not limited to the position only, and what kind of arrangement is used as a reference is not particularly limited. For example, in the frequency spectrum, the vertical axis represents luminance and the horizontal axis represents frequency. In the luminance distribution, the vertical axis may be the luminance, and the horizontal axis may be the position.
Further, the analysis unit 11 analyzes the luminance distribution by extracting data related to reflected light or scattered light at a desired frequency from the database 10 using, for example, the frequency selected by the user as a key. If analysis is possible by dividing the frequency, an image and a graph at each frequency can be displayed by a switching operation of the output unit described later.

The output unit 12 is, for example, a display device such as a CRT, liquid crystal, organic EL (electroluminescence) or plasma display, or a transmitter that can transfer a signal without direct display. In a display device such as a CRT, data relating to the frequency spectrum and the luminance distribution obtained by the analysis unit 11 can be displayed as an image. In the transmitter, these data are output as signals, and these signals are received by a separate display or the like to display the images, thereby enabling remote confirmation of the images. Specifically, it is suitable for a case where an image taken in an operating room is displayed in a remote control room or the like and is monitored by an expert other than the operator and advice or diagnosis is communicated in a timely manner.
The amplifying unit 9, the database 10, and the analyzing unit 11 may be omitted, and only the output unit 12 may be connected to the camera 3. In this case, an image captured by the camera 3 is simply displayed in the output unit 12. Displayed or signal output.

Next, results obtained using the in-vivo part position detection system according to the present embodiment will be described with reference to FIGS.
3A is an actual photograph of the marking clip, FIG. 3B is an image captured by the body part position detection system according to the present embodiment, and FIG. 3C is captured by the conventional imaging system. It is an image that was made.
In FIG. 3 (a), the marking clip was taken in a state where it was placed on a single cow large intestine section. 3 (b) and 3 (c), the marking clip is further covered with a bovine large intestine slice having a thickness of about 3 mm, and images are taken by the body part position detection system according to the present embodiment and the conventional imaging system. .
In FIG. 3 (b), in the in-vivo part position detection system according to the present embodiment, a black image that can be confirmed at the center is a marking clip image, and is based on scattered light of near infrared rays mainly irradiated by the presence of the marking clip. An image is taken as a low luminance part (hereinafter referred to as a cold spot). Further, in the image in FIG. 3B, since the surface reflected light of the living tissue is removed by the polarization filter, the contrast of the marking clip image is clear.
On the other hand, in FIG. 3C, it can be seen that in the conventional imaging system, the intensity of the reflected light is high and it is difficult to confirm the marking clip image. Further, even if the shutter speed is increased to improve the contrast, the intensity of the reflected light also increases, so that the marking clip image cannot be detected.

Next, reflected light and scattered light will be described with reference to FIG.
FIG. 4A is an image at a wavelength of 700 nm imaged by the body part position detection system according to the present embodiment, and FIG. 4B is a graph showing a luminance distribution at a wavelength of 700 nm.
In FIG. 4A, in the image, a black rectangular shadow can be confirmed at the center, and this black portion is a cold spot mainly based on the scattered light of the marking clip. Further, although it is difficult to visually recognize, a high-luminance portion based on the reflected light of the marking clip exists at the center of the black square.
FIG. 4B shows the luminance distribution at the horizontal position of the dotted line portion as shown in FIG. 4A, and shows the depth Z as a parameter. The unit of the horizontal axis is a pixel unit, and one pixel is one pixel.
At any depth, the luminance distribution has a low luminance portion showing a cold spot at 500 to 600 pixels, and as the depth becomes deeper, the amount of change of the cold spot becomes smaller. This low-luminance portion is a black square-shaped portion shown in FIG. Further, when the depth is 0 mm at the same position, a peak due to the reflected light is clearly recognized, and the peak due to the reflected light disappears as the depth increases. In other words, it is difficult to detect cold spots and reflected light as the depth increases. However, as shown in FIG. 4B, the amount of change in luminance at depths of 0 mm and 4 mm is greater for the change due to the cold spot than for the reflection.

Next, the relationship between the brightness change amount of the cold spot detected in FIG. 4 and the brightness change amount of the peak due to the reflected light and the depth will be described with reference to FIG.
FIG. 5 is a graph showing the relationship between the luminance change amount and the depth detected by the in-vivo part position detection system according to the present embodiment.
In FIG. 5, as the amount of change in luminance, a value obtained by calculating the minimum intensity value of the cold spot portion as the contrast is used. Although all of the luminance change amounts decrease as the depth (Z) increases, it can be confirmed that at the wavelength of 1000 nm, the contrast of the cold spot and the hot spot increases by about 10% with respect to the wavelength of 830 nm. It can also be confirmed that the contrast of the cold spot and the hot spot is lowered at 1300 nm longer than the wavelength of 1000 nm. From FIG. 5, it is considered that the dynamic range of the depth (Z) can be expanded to 3 to 4 mm. Since the large intestine wall is about 3 mm, it can be predicted that the marking clip position can be identified by detecting a cold spot.

Next, the influence of reflected light will be described with reference to FIG.
FIG. 6A is a marking clip before removal of the surface reflected light imaged by the body part position detection system according to the present embodiment, and FIG. 6B is a marking clip after removal of the surface reflected light. And (c) is a graph showing the luminance distribution before and after the removal of the surface reflected light. In FIGS. 6A and 6B, the marking clip is imaged in a state of being placed on the living tissue.
In FIG. 6A, in the marking clip and the biological tissue before removing the surface reflected light, the high-intensity portions generated by the surface reflected light are whitened and recognized at a plurality of locations. On the other hand, in FIG. 6B, it can be seen that the surface reflected light is removed by installing the polarizing filter, and the high-luminance part recognized in FIG. 6A disappears.
6 (a) and 6 (b), the color of the living tissue is different, but in FIG. 6 (a), there is a portion where the luminance is high due to the reflected light, and the luminance is lowered overall, so The tissue portion becomes dark, and FIG. 6B is the opposite.
FIG. 6C shows the luminance distribution at the horizontal position of the dotted line portion shown in FIGS. 6A and 6B, and the luminance distribution having two peaks is recognized before the surface reflected light is removed. It is done. The peak in the vicinity of 1200 pixels is caused by the reflected light on the living tissue, and is a portion that appears white on the right side of the dotted line in FIG. On the other hand, the peak of 700 to 800 pixels is a combination of the peak due to the reflected light of the marking clip and the cold spot due to the scattered light.
After removing the surface reflected light, the two peaks disappear and only the cold spot is clear in 700 to 800 pixels. If the surface reflected light is removed by installing a polarizing filter, the cold spot can be easily confirmed. It turns out that it becomes.

Next, the influence of the reflectance of the marking clip will be described with reference to FIG.
FIG. 7A is an image when the marking clip reflectance imaged by the in-vivo part position detection system according to the present embodiment is 2%, and FIG. 7B is the same when the marking clip reflectance is 30%. (C) is a graph showing the luminance distribution at each marking clip reflectance.
In FIG. 7A, when the marking clip reflectance is 2%, a cold spot can be clearly confirmed in the center of the image. On the other hand, in FIG. 7B, when the marking clip reflectance is 30%, a high-luminance portion due to vertically reflected light can be confirmed in the center of the image, and a slight cold spot is recognized around this high-luminance portion. It is done.
In FIG. 7C, the luminance distribution varies greatly depending on the marking clip reflectance. As the marking clip reflectance increases, the peak due to the reflected light of the marking clip becomes clear. Conversely, the marking clip reflectance is low. Then, the peak due to the reflected light becomes small and the cold spot becomes clear. Therefore, it can be said that lowering the marking clip reflectance is more advantageous for cold spot detection.

Next, the influence of the wavelength will be described with reference to FIGS.
FIG. 8 is a graph showing the normalized luminance distribution at each wavelength detected by the in-vivo part position detection system according to the present embodiment. In FIG. 8, the simulation is performed by changing the detection wavelength to 700 nm, 830 nm, 1000 nm, and 1300 nm while fixing the depth Z = 3 mm, the numerical aperture of the camera lens to 0.1, and the reflectance to 10%.
In FIG. 8, it can be seen that when the detection light has a high wavelength, the decrease in luminance is increased to about 30% at a cold spot at a wavelength of 1000 nm, but decreases at a wavelength of 1300 nm.

Next, the luminance distribution in FIG. 8 will be described with reference to FIG. 9 as an image captured for each wavelength.
FIG. 9A is an image at a wavelength of 700 nm captured by the body part position detection system according to the present embodiment, FIG. 9B is an image at a wavelength of 830 nm, and FIG. It is an image at a wavelength of 1000 nm, and (d) is an image at a wavelength of 1320 nm. Also in these drawings, the conditions for the depth Z = 3 mm, the numerical aperture of the camera lens to be 0.1, and the reflectance to be 10% are the same as those in FIG.
9A to 9D, although it is not clear in an image having a wavelength of 700 nm, a high-intensity portion due to reflected light can be more clearly confirmed as the wavelength is increased from 830 nm to 1000 nm, and the contrast is increased. Will also be clear. However, in the case of 1300 nm where the wavelength is even higher, the contrast is unclear.

Next, FIG. 10 is a graph showing the luminance distribution at each wavelength detected by the body part position detection system according to the present embodiment.
In FIG. 10, it can be seen that the peak and cold spot due to the reflected light are recognized at 40 to 60 pixels in the luminance distribution at any wavelength, and the peak due to the reflected light becomes larger as the wavelength becomes higher.
FIG. 10 includes wavelength information, which is a luminance distribution as well as a frequency spectrum.
As shown in the figure, the luminance change amount of the peak and cold spot due to the reflected light is measured, and the relationship between the luminance change amount and the wavelength is shown in FIG.
FIG. 11 is a graph showing the relationship between the luminance change amount and the wavelength detected by the in-vivo body part position detection system according to the present embodiment.
In FIG. 11, the amount of change in peak brightness due to reflected light increases as the wavelength increases, while the amount of change in brightness due to cold spots tends to increase slightly as the wavelength increases, but the dependence on wavelength is small.
Therefore, although the influence of the wavelength is small in the cold spot, the peak due to the reflected light becomes clearer as the wavelength is higher. Therefore, it can be seen that the detection sensitivity is improved when the wavelength in the high wavelength region of about 1000 nm is used.

In the present embodiment configured as described above, the marking clip sandwiched at a desired position in the body is irradiated with near-infrared rays having high safety to the human body, and the reflected light and scattered light from the marking clip are imaged. As the position of the marking clip can be detected quickly and accurately by imaging as a burden on the patient or the operator in operations such as laparoscopic surgery by holding the marking clip at a position such as a lesion in the body It is possible to determine the position of the lesioned part and apply appropriate treatment.
Further, in the present embodiment, there are influences of the following factors, and the frequency spectrum and the luminance distribution based on the reflected and scattered light images of the marking clip imaged by selecting the best conditions. Analysis becomes easy.
First, when a near-infrared absorbing material such as ICG is applied to the marking clip, it is possible to accurately detect only the cold spot due to scattered light while suppressing the reflection of the marking clip.
Further, when a polarizing filter is installed in the light source and the camera to remove the reflected light from the surface of the living tissue or to reduce the reflectance of the marking clip, it is easy to detect a cold spot due to scattered light.
And if the wavelength of the near infrared rays to radiate is made into a high wavelength range, the peak by reflected light can be detected with sufficient sensitivity.

  As described above, the invention described in claims 1 to 6 of the present invention is capable of detecting a desired position in the body accurately and quickly, and also provides a body part position detection system that is safe for the human body. It can be provided, and can be used for endoscopy and the like in laparoscopic surgery.

1 is a conceptual diagram of a body part position detection system according to an embodiment of the present invention. It is a block diagram of the in-vivo site | part position detection system which concerns on this Embodiment. (A) is an actual photograph of the marking clip, (b) is an image captured by the body part position detection system according to the present embodiment, and (c) is an image captured by a conventional imaging system. . (A) is an image at a wavelength of 700 nm captured by the in-vivo body part position detection system according to the present embodiment, and (b) is a graph showing a luminance distribution at a wavelength of 700 nm. It is a graph which shows the relationship between the luminance variation detected by the in-vivo part location detection system which concerns on this Embodiment, and depth. (A) is the marking clip before the removal of the surface reflected light imaged by the body part position detection system according to the present embodiment, (b) is the marking clip after the removal of the surface reflected light, and (c) ) Is a graph showing the luminance distribution before and after the removal of the surface reflected light. (A) is an image when the marking clip reflectivity imaged by the body part position detection system according to the present embodiment is 2%, and (b) is an image when the marking clip reflectivity is 30%. And (c) is a graph showing the luminance distribution at each marking clip reflectance. It is a graph which shows the normalized luminance distribution in each wavelength detected by the in-vivo part location detection system which concerns on this Embodiment. (A) is an image at a wavelength of 700 nm imaged by the body part position detection system according to the present embodiment, (b) is an image at a wavelength of 830 nm, and (c) is an image at a wavelength of 1000 nm. (D) is an image at a wavelength of 1320 nm. It is a graph which shows the luminance distribution in each wavelength detected by the in-vivo site | part position detection system which concerns on this Embodiment. It is a graph which shows the relationship between the brightness | luminance variation | change_quantity detected by the in-vivo site | part position detection system which concerns on this Embodiment, and a wavelength.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Body part position detection system 2 ... Light source 3 ... Camera 4 ... Marking clip 5 ... Biological tissue 6 ... Band pass filter 7 ... Polarizing filter 8 ... Abdominal wall 9 ... Amplification part 10 ... Database 11 ... Analysis part 12 ... Output part

Claims (6)

  A light source unit that emits near-infrared rays, a clamping unit that clamps a desired body part, and an imaging unit that receives reflected light and / or scattered light from the clamping unit that emits near-infrared rays emitted from the light source unit. Body part position detection system characterized by.   A light source unit that emits near-infrared rays, a clamping unit that is coated with a near-infrared absorbing material on the surface and sandwiches a desired body part, and an imaging unit that receives scattered light from the clamping unit of near-infrared rays emitted from the light source unit A body part position detection system characterized by comprising:   The in-vivo part position detection system according to claim 1 or 2, wherein the light source unit and / or the imaging unit includes a filtering unit that transmits near infrared rays in a range of 700 nm to 1300 nm.   4. The internal body according to claim 1, wherein the light source unit and / or the imaging unit includes a polarizing unit that transmits near infrared rays having a polarization plane in a desired direction. 5. Site position detection system.   5. The internal body part according to claim 1, further comprising an output unit that displays or outputs a signal of data relating to reflected light and / or scattered light received by the imaging unit as an image. 6. Position detection system.   An optical information storage unit that stores data related to reflected light and / or scattered light received by the imaging unit in a readable manner, and reads the data related to the reflected light and / or scattered light from the optical information storage unit to read the reflected light. And / or an analysis unit that analyzes the frequency spectrum and / or luminance distribution of the scattered light, and the output unit displays or signals data on the frequency spectrum and / or luminance distribution obtained by the analysis unit as an image. 6. The body part position detection system according to claim 5, wherein the body part position detection system outputs the body part.