JP2013244343A - Biological information presentation device and biological information presentation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biological information presentation device and a biological information presentation method capable of easily and accurately visualizing information of a living body such as the position, thickness and direction of a blood vessel that can not be accurately identified before.SOLUTION: Combining processing of two-dimensional blood vessel information obtained by irradiating a part desired to be visualized of a living body with near infrared light from a first inspection light source with two or more pieces of tomographic image information obtained by irradiating the part with the near infrared light from a second inspection light source is performed. Then, three-dimensional composite image information and two-dimensional composite image information obtained by the combining processing are image-displayed.

Description

  The present invention relates to a biological information presentation apparatus and a biological information presentation method for easily and accurately imaging and presenting not only blood vessels close to the surface of a living body but also blood vessels in a deep part of a living body.

  In order to perform intravenous injection or drip on a person, it is necessary to first confirm the exact position of the vein for puncturing the injection needle or catheter. In addition, for patients with renal insufficiency who cannot purify blood with the kidneys, when hemodialysis is performed at home, the patient himself or a caregiver performs a procedure of inserting a needle into the blood vessel of the arm. It is necessary to confirm the exact position.

  In order to satisfy these requirements, conventionally, a vein with a depth of 3 to 7 mm from the skin is irradiated by irradiating a site where the near infrared ray is desired to be visualized and photographing with reflected light using a CCD camera or the like for the near infrared ray. There is a device for imaging and visualizing the image (for example, see Patent Document 1).

  In addition, in a scattering medium imaging device using a relative detector, tomographic information of a living body can be obtained by applying the principle of diffuse light tomography (see, for example, Patent Document 2).

JP 2011-160891 A Special table 2003-528191 gazette

However, the prior art has the following problems.
With a conventional device as disclosed in Patent Document 1, it is possible to visualize blood vessels close to the surface of a living body, but it is very difficult to visualize deep blood vessels.

  In addition, since it is visualized by detecting the intensity of the reflected light from the surface of the living body, even if it is a thick blood vessel, if it is in the deep layer, the reflected light will be weakened due to the influence of the living tissue, so it will appear thin. End up.

  As a result, the thickness of the visualized blood vessel does not match the actual thickness of the blood vessel. Furthermore, it cannot even be estimated how deep the blood vessel is from the surface of the living body.

  In the conventional apparatus as shown in Patent Document 2, in order to obtain information on the deep part of the living body, optical characteristic parameters such as a scattering coefficient and an absorption coefficient of the living body part are assumed and analyzed using a light propagation model. Then, a tomographic image is obtained while performing back calculation so that the calculation result converges to the near-infrared light reception result irradiated on the living body.

  However, at present, there is a problem that the analysis time required to converge the calculation result is very long. In addition, although a tomographic image can be obtained with an apparatus such as that disclosed in Patent Document 2, the relevance to visualizing blood vessels in a living body is not ensured.

  The present invention has been made in order to solve the above-described problems, and can easily and accurately visualize biological information such as the position, thickness, and direction of a blood vessel that could not be accurately identified in the past. An object of the present invention is to obtain a biometric information presentation device and a biometric information presentation method.

  The biological information presentation apparatus according to the present invention includes a first inspection light source and a second inspection light source that irradiate near-infrared light on the surface of the living body, and a first inspection to visualize the inside from the surface of the living body. First visualization information that irradiates near-infrared light to the range to be visualized in the living body from the light source for the subject, captures the range to be visualized using the reflected light of the irradiated near-infrared light, and acquires image information of the photographed range An acquisition unit, a two-dimensional blood vessel information generation unit that generates two-dimensional blood vessel information for each of a plurality of lines in the region visualized by the image information acquired by the first visualization information acquisition unit, and a second examination light source A second light source light emitting / receiving array unit that irradiates near-infrared light on one line from a plurality of lines and detects light emitted from the irradiated near-infrared light again at a plurality of points; When light is detected by the second light source emission / reception array Assuming an initial distribution of optical characteristic parameters in the living body and a time-resolved measurement unit that performs change measurement and calculates a measurement value of the time-change measurement of the detected light, and based on the assumed initial distribution of optical characteristic parameters Calculates the calculated value of time change, compares the calculated value with the measured value calculated by the time-resolved measurement unit, and keeps the optical until the error between the measured value and the calculated value falls within the predetermined tolerance. By adjusting the initial distribution of the characteristic parameters and repeating the comparison process, an inverse problem analysis unit that determines an optical characteristic parameter whose error falls within an allowable value and generates reconstructed image information based on the determined optical characteristic parameter; Based on the reconstructed image information generated by the inverse problem analysis unit, a tomographic image information generation unit that generates corresponding tomographic image information on one line, and a two-dimensional blood vessel information generation unit It is generated by performing a series of processes by the second light source emission / light reception array unit, the time-resolved measurement unit, the inverse problem analysis unit, and the tomographic image information generation unit in correspondence with arbitrary line positions of the generated multiple lines. Three-dimensional synthetic image information and two-dimensional synthetic image are obtained by performing synthesis processing based on tomographic image information corresponding to an arbitrary line position and two-dimensional blood vessel information of each of a plurality of lines generated by the two-dimensional blood vessel information generation unit. A composite image information generation unit that generates information, and a biological information display unit that displays the three-dimensional composite image information and the two-dimensional composite image information generated by the composite image information generation unit. The two-dimensional blood vessel information generated by the two-dimensional blood vessel information generation unit for each of the plurality of lines, and the tomographic image information generation unit corresponding to an arbitrary line position 3D composite image information related to blood vessels in 2D blood vessel information is generated by combining the tomographic image information so that the blood vessel portions included in the respective tomographic image information corresponding to a specific part overlap each other. Among the tomographic image information generated by the tomographic image information generation unit corresponding to an arbitrary line position with respect to a specific part of the blood vessel in the two-dimensional blood vessel information generated for each of the plurality of lines by the two-dimensional blood vessel information generation unit Generating two-dimensional composite image information about a blood vessel in two-dimensional blood vessel information by performing hue processing while referring to the luminance and hue of the blood vessel portion included in each tomographic image information corresponding to a specific part It is what.

  In addition, the biological information presentation method according to the present invention includes biological information including a first inspection light source and a second inspection light source that irradiates near-infrared light on the surface of the living body in order to visualize the inside from the surface of the living body. A biological information presentation method executed by a presentation device, wherein a range to be visualized using a reflected light of the irradiated near-infrared light by irradiating near-infrared light to a range to be visualized in a living body from a first examination light source A two-dimensional blood vessel for each of a plurality of lines in a region visualized by the first visualization information acquisition step and the image information acquired in the first visualization information acquisition step. Two-dimensional blood vessel information generating step for generating information, and irradiating near-infrared light on one line of a plurality of lines from the second examination light source, and the irradiated near-infrared light again comes out on the surface of the living body Inspection at multiple points Time-resolved measurement to measure the time change of the light detected in the second light source emission / light reception array detection step and the second light source emission / light reception array detection step, and to calculate the measurement value of the time change measurement of the detected light Assuming the initial distribution of optical characteristic parameters in the living body and the step, the calculated value of the time change of light is calculated based on the assumed initial distribution of the optical characteristic parameter, and calculated in the calculated calculation value and the time-resolved measurement step Perform the comparison process with the measured value and repeat the comparison process by adjusting the initial distribution of the optical characteristic parameters until the error between the measured value and the calculated value falls within the predefined tolerance value. Inverse problem analysis step for generating reconstructed image information based on the determined optical property parameter and the inverse problem analysis step. Based on the reconstructed image information, a tomographic image information generation step for generating corresponding tomographic image information on one line and an arbitrary line position of a plurality of lines when the two-dimensional blood vessel information is generated by the two-dimensional blood vessel information generation step Correspondingly, tomographic image information corresponding to an arbitrary line position generated by performing a series of processes by the second light source emission / light receiving array detection step, the time-resolved measurement step, the inverse problem analysis step, and the tomographic image information generation step And a composite image information generation step for generating three-dimensional composite image information and two-dimensional composite image information by performing a synthesis process based on the two-dimensional blood vessel information of each of the plurality of lines generated in the two-dimensional blood vessel information generation step, , Biometric information for displaying 3D composite image information and 2D composite image information generated in the composite image information generation step A composite image information generation step, wherein the composite image information generation step is arranged at a specific part of the blood vessel in the two-dimensional blood vessel information generated for each of the plurality of lines in the two-dimensional blood vessel information generation step, and at any line position in the tomographic image information generation step By combining the tomographic image information generated so as to overlap with the blood vessel portion included in each tomographic image information corresponding to a specific part, the three-dimensional composite image related to the blood vessel in the two-dimensional blood vessel information Generate a specific portion of the blood vessel in the two-dimensional blood vessel information generated for each of a plurality of lines in the information generation step and the two-dimensional blood vessel information generation step, corresponding to an arbitrary line position in the tomographic image information generation step Of the tomographic image information included in each tomographic image information corresponding to a specific site. And the hue by performing a reference while the hue processing, is characterized in that a step of generating a two-dimensional composite image information on a blood vessel in the two-dimensional blood vessel information.

  According to the biological information presentation device and the biological information presentation method of the present invention, the two-dimensional blood vessel information of the part to be visualized of the living body and the plurality of pieces of tomographic image information corresponding to the part are synthesized and obtained by the synthesis process. By displaying two-dimensional or three-dimensional image information, a biological information presentation device that can easily and accurately visualize biological information such as the position, thickness, and direction of blood vessels that could not be accurately identified in the past, and A biometric information presentation method can be obtained.

It is the block diagram which showed the function structure of the biometric information presentation apparatus in Embodiment 1 of this invention. It is explanatory drawing which shows the relationship between the biometric information presentation apparatus in Embodiment 1 of this invention, and the biological body which is a measuring object. In Embodiment 1 of this invention, it is the schematic diagram which showed the near-infrared image and visible synthetic | combination image which synthesize | combined these images, and the near-infrared image at the time of image | photographing an arm. It is explanatory drawing in which the two-dimensional blood vessel information generation part in Embodiment 1 of this invention produces | generates two-dimensional blood vessel information. It is a flowchart explaining the case where the inverse problem analysis part in Embodiment 1 of this invention produces | generates reconstruction image information with the conventional processing method and the processing method of this invention. In Embodiment 1 of this invention, it is the schematic diagram which showed the three-dimensional synthetic | combination image information displayed as an image, and two-dimensional synthetic | combination image information.

  Hereinafter, preferred embodiments of the biological information presentation device and the biological information presentation method of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

Embodiment 1 FIG.
<1. Configuration of biological information presentation device>
FIG. 1 is a block diagram showing a functional configuration of the biological information presentation apparatus in Embodiment 1 of the present invention.

  1 includes a first visualization information acquisition unit 10, a two-dimensional blood vessel information generation unit 20, a two-dimensional blood vessel information storage unit 30, a second light source emission / light reception array unit 40, and a pico pulse light control unit. 50, time-resolved measurement unit 60, inverse problem analysis unit 70, tomographic image information generation unit 80, light emitting / receiving array movable support unit 90, tomographic image information storage unit 100, composite image information generation unit 110, biological information display unit 120, A biological reference information generation unit 130 and a biological information presentation device control unit 140 are provided.

  The first visualization information acquisition unit 10 obtains biological information necessary for visualizing the blood vessels of the living body. The two-dimensional blood vessel information generation unit 20 generates two-dimensional position information of the blood vessel based on the biological information obtained by the first visualization information acquisition unit 10.

  The two-dimensional blood vessel information storage unit 30 stores the two-dimensional blood vessel information generated by the two-dimensional blood vessel information generation unit 20 in association with the position where the tomographic image is generated. The second light source emission / reception array section 40 includes a light emission / reception block installed so that each of the second light source and the photodetector is paired.

  The pico pulse light control unit 50 controls the light emission of the second light source in the second light source emission / light reception array unit 40. The time-resolved measurement unit 60 measures the time change of the emitted light when the light irradiated to the body part to be measured by the second light source comes out again on the surface of the living body while repeating scattering and absorption in the living body. I do.

  The inverse problem analysis unit 70 converges to each measurement value using the time-resolved measurement value generated by the time-resolved measurement unit 60 and the light propagation model assuming the optical characteristic parameters such as the scattering coefficient and the absorption coefficient of the living body part. Thus, reverse calculation is performed to generate reconstructed image information.

  Based on the reconstructed image information generated by the inverse problem analysis unit 70, the tomographic image information generation unit 80 generates tomographic image information of a biological part that presents the blood volume, oxygen concentration, and the like in the biological tissue with luminance and hue. The light emission / light reception array movable support section 90 moves the second light source light emission / light reception array section 40 in a predetermined direction in order to obtain tomographic image information of different living body parts.

  The tomographic image information storage unit 100 stores the tomographic image information of each biological part obtained by the movement of the second light source emission / light receiving array unit 40 in association with the measurement position of the biological part.

  The composite image information generation unit 110 performs two-dimensional blood vessel information correction processing and two-dimensional blood vessel information based on the two-dimensional blood vessel information stored by the two-dimensional blood vessel information storage unit 30 and the tomographic image information stored by the tomographic image information storage unit 100. Information processing is performed in which a predetermined part of information is associated with tomographic image information corresponding to the predetermined part.

  The biometric information display unit 120 displays an image to visualize the biometric information processed by the composite image information generation unit 110. The biological reference information generation unit 130 gives known biological reference information such as two-dimensional blood vessel information and tomographic image information to the inverse problem analysis unit 70.

  The biological information presentation device control unit 140 instructs a necessary operation to each functional unit included in the biological information presentation device in order to operate the device.

  Next, a case where a living body that is a measurement target is measured using the biological information presentation apparatus according to the first embodiment will be described with reference to FIG. FIG. 2 is an explanatory diagram illustrating a relationship between the biological information presentation device and the living body to be measured according to the first embodiment of the present invention.

  For the sake of specific explanation, hereinafter, the living body to be measured is referred to as the arm 150. Of course, in the living body display device according to the present invention, not only the arm but also another living body other than the arm can be measured.

  The 1st visualization information acquisition part 10 is provided with the near-infrared laser 11, the lens 12, the optical filter 13, and the image pick-up element 14 so that it may show in figure.

  The near-infrared laser 11 is a first inspection light source located at an upper part several cm away from the arm, and a portion of the arm 150 where light having a wavelength of 700 nm to 1200 nm is desired to be visualized (in FIG. 2, a dotted line) (Equivalent to the enclosed area).

  The lens 12 condenses the reflected light of the light irradiated by the first inspection light source onto the portion of the arm 150 that is desired to be visualized. The optical filter 13 switches the wavelength that passes through the filter according to the case of capturing a visible image and the case of capturing a near-infrared image.

  The imaging device 14 has high spectral sensitivity for visible wavelengths to near infrared wavelengths of about 1200 nm, has a surface configuration of 640 pixels in the horizontal direction and 480 lines in the vertical direction, and each pixel is quantized and output in 8 bits. . Note that the number of pixels, the number of lines, and the number of bits affect the resolution, but are not limited thereto.

  The second light source light emitting / light receiving array unit 40 moves along the arm 150 within the range of the light emitting / light receiving array movable support unit 90 based on the control signal of the biological information presentation device control unit 140 to thereby change the measurement site. Can be changed. The second light source emission / light reception array unit 40 is in close contact with the arm 150 as shown in the figure.

  Then, the tomographic image information generation unit 80 generates tomographic image information corresponding to the position of each measurement region (approximately one line), and as a result, the region (in FIG. It is possible to obtain tomographic image information corresponding to the entire range of a portion surrounded by a dotted line.

  The second light source for inspection and the light detector installed in one light emitting / receiving block provided in the second light source emitting / receiving array unit 40 are as follows.

  That is, as the second inspection light source, for example, a near-infrared laser that outputs light of two types of wavelengths such as a first wavelength and a second wavelength is used. As the photodetector, for example, a compound-based photodetector such as Si or InGaAs is used.

  In addition, although it was set as two types of wavelengths, a 1st wavelength and a 2nd wavelength, about the kind of wavelength which a near-infrared laser outputs, it is not limited to this. That is, the type of wavelength is a parameter that affects the resolution of the tomographic image, and may be one type or three or more types of wavelengths as necessary.

  The N light emitting / receiving blocks 41 (1) to 41 (N) installed in the second light source emitting / receiving array unit 40 have arms 150 as shown in the drawing. It is shaped to wrap around the measurement site.

  Note that a higher-resolution tomographic image can be obtained as the number of light emitting / receiving blocks increases. The number of light emitting / receiving blocks may be changed according to the required resolution.

<2. Operation of biological information presentation device>
Next, the operation procedure of the biometric information presentation apparatus according to Embodiment 1 of the present invention will be described while describing the operation contents of each functional unit in detail.

  First, the operation of the first visualization information acquisition unit 10 will be described with reference to FIG. 1, FIG. 2, and FIG. FIG. 3 is a schematic diagram showing a near-infrared image, a visible image, and a near-infrared / visible combined image obtained by combining these images when the arm 150 is photographed in the first embodiment of the present invention.

  Based on the control signal of the biological information presentation device control unit 140, the first visualization information acquisition unit 10 determines the epidermis of the arm 150 located in the light emitting / receiving array movable support unit 90 area as shown in FIG. As a near-infrared image and a visible image, images are taken intermittently in time division.

  Note that, as illustrated in FIG. 2, the imaged range is a portion surrounded by a dotted line on the skin of the arm 150. In this case, not only the arm 150 but also a part of the second light source light emitting / receiving array section 40 is reflected in the image.

  In the case of taking a near-infrared image, the optical filter 13 sets the filter so as to block the visible wavelength and allow the near-infrared wavelength to pass. And the lens 12 condenses the reflected light of the light which the near-infrared laser 11 irradiated to the skin of the arm 150, and the image pick-up element 14 converts into image information with reflected light.

  Near-infrared light irradiated on the epidermis of a living body transmits the skin and is absorbed by blood in the blood vessel, while it is reflected by a human tissue such as a fat layer in a portion other than the blood vessel. . As a result, in the image information converted by the image sensor 14, the blood vessel portion has a relatively low luminance, and other portions other than the blood vessel have a relatively high luminance.

  On the other hand, in the case of capturing a visible image, the near-infrared laser 11 stops irradiation, and the optical filter 13 sets a filter so as to pass the visible wavelength and block the near-infrared wavelength. The lens 12 collects the reflected light of natural light that illuminates the skin of the arm 150, and the image sensor 14 converts the image information into image information by the reflected light.

  In the case of changing the shooting from a near-infrared image to a visible image, the optical filter 13 is set so that two types of filters are slid or rotated.

  FIG. 3 is a schematic diagram showing a near-infrared image, a visible image, and a near-infrared / visible combined image obtained by synthesizing these images obtained by photographing the arm 150 as described above. The near-infrared image in FIG. 3 is a monochrome image with black and white and different luminance. Further, as shown in the figure, in the contour of the photographed arm 150, the images of the blood vessels 151 and 152 have lower luminance than the other parts, so that they are confirmed as black streaks.

  In the near-infrared image, a part of the second light source emission / light reception array unit 40 is also shown. However, since the appearance of the image varies greatly depending on the appearance material of the second light source light emitting / receiving array unit 40, the description is omitted here.

  On the other hand, the visible image in FIG. 3 is a color image, and what is directly viewed by human eyes is taken as an image as it is. Further, as shown in the drawing, a part of the second light source light emitting / receiving array section 40 is shown in the upper part of the screen, but blood vessels are hardly shown. In the visible image, blood vessels may appear, but it is clearly difficult to see compared to the near-infrared image.

  And the 1st visualization information acquisition part 10 synthesize | combines the near-infrared image and the visible image which were image | photographed intermittently by time division in this way, and a near-infrared / visible composition as shown in FIG. Generate an image.

  It should be noted that the time interval and the number of times of capturing the near-infrared image and the visible image intermittently in a time-sharing manner can be changed by setting shooting parameters as necessary.

  Next, the operation of the two-dimensional blood vessel information generation unit 20 will be described with reference to FIG. 3 and FIG. FIG. 4 is an explanatory diagram in which the two-dimensional blood vessel information generation unit 20 according to the first embodiment of the present invention generates two-dimensional blood vessel information.

  The two-dimensional blood vessel information generation unit 20 extracts the luminance information of the near-infrared image captured by the first visualization information acquisition unit 10 by a low-pass filter process that performs peripheral pixel addition averaging, and the luminance is lower than a predetermined threshold. Information is generated using a part as a blood vessel part.

  Specifically, the two-dimensional blood vessel information generation unit 20 corresponds to each pixel value (corresponding to the dot illustrated in FIG. 4) on the P (1 ≦ P ≦ 480) line illustrated in the near-infrared / visible composite image in FIG. ) Is subjected to low-pass filter processing.

  Note that, as illustrated in FIG. 4, among the luminance pixels indicated by the solid line corresponding to the dots, the luminance pixels equal to or lower than the threshold are pixel information visualized as blood vessel sites.

  Then, the two-dimensional blood vessel information generation unit 20 repeats the same processing from the first line (P = 1) to the last (P = 480) line in order, thereby performing the two-dimensional blood vessel for each of the plurality of lines. Generate information. Furthermore, the two-dimensional blood vessel information storage unit 30 temporarily stores the two-dimensional blood vessel information generated by the two-dimensional blood vessel information generation unit 20.

  The temporarily stored two-dimensional blood vessel information is stored in a form associated with each line of the two-dimensional blood vessel information and a position where tomographic image information is generated. The tomographic image information will be described later.

  Next, out of the N light emitting / receiving blocks 41 (1) to 41 (N) provided in the second light source emitting / receiving array section 40, one light emitting / receiving block (here, 41 (1)). The following operation is performed.

  That is, the near-infrared laser in the light emitting / receiving block 41 (1) has a wavelength of the first wavelength (here, description is made using the first wavelength of two types of wavelengths), and the period is, for example, 100 picoseconds. The following pulsed light is irradiated onto one line of a plurality of lines where the two-dimensional blood vessel information is generated.

  In addition, this irradiation by a near-infrared laser is performed based on the control signal of the pico pulse light control part 50 which received the control signal of the biometric information presentation apparatus control part 140. FIG.

  The light irradiated to the arm 150 by the near-infrared laser in the light emitting / receiving block 41 (1) is repeatedly absorbed and scattered inside the arm 150, and the light other than the light emitting / receiving block 41 (1) irradiated. The N-1 light emitting / receiving blocks 41 (2) to 41 (N) are detected by the photodetectors.

  Furthermore, the light detected by each photodetector in the light emitting / receiving blocks 41 (2) to 41 (N) is converted into an electrical signal. Then, the time-resolved measurement unit 60 to which each signal is sent generates time change information of the detection light based on each sent signal.

  The same operation is performed when the near-infrared laser wavelength is not only the first wavelength but also the second wavelength. Further, the same operation as that of the light emission / light reception block 41 (1) is performed for the light emission / light reception blocks 41 (2) to 41 (N).

  That is, the biological information presentation device control unit 140 sequentially switches the infrared lasers in the respective light emitting / receiving blocks so that the same operation is performed in all the light emitting / receiving blocks.

  Therefore, the time-resolved measurement unit 60 has a huge amount of data obtained by multiplying the number of light detectors for N-1 blocks × the number of laser irradiations for N blocks × the time change measurement span divided by the measurement period at each wavelength. Is generated.

  Next, the inverse problem analysis unit 70 performs generation processing of reconstructed image information necessary for obtaining tomographic image information according to the principle of diffuse light tomography based on the data generated by the time-resolved measurement unit 60.

  Next, reconstructed image information generation processing according to the principle of diffuse light tomography performed by the inverse problem analysis unit 70 will be described with reference to the flowchart of FIG. 5 in comparison with a conventional processing method. FIG. 5 is a flowchart illustrating a case where the inverse problem analysis unit 70 according to Embodiment 1 of the present invention generates reconstructed image information by the conventional processing method and the processing method of the present invention.

  Up to now, the conventional processing method in FIG. 5A repeats the convergence processing loop until the error between the calculation result and the measurement result falls within the allowable value. The time required was necessary.

  On the other hand, the processing method of the present invention in FIG. 5B has the technical feature that the processing is simplified and the processing circuit scale can be reduced and the processing time can be shortened as compared with the conventional processing method. Yes.

  First, a procedure in which the inverse problem analysis unit 70 generates reconstructed image information by a conventional processing method will be described with reference to FIG.

  First, in step S501, the inverse problem analysis unit 70 assumes an initial distribution of the absorption coefficient μa (r) and the converted diffusion coefficient μs ′ (r), which are optical characteristic parameters in the biological tissue to be measured. Next, in step S502, the inverse problem analysis unit 70 performs forward problem calculation using the light propagation model based on the initial distribution assumed in step S501.

  Next, the inverse problem analysis unit 70 calculates the light intensity at each detection point in step S503. Next, in step S504, the inverse problem analysis unit 70 compares the calculation result calculated in step S503 with the actual measurement result detected by each detector, and the error between the calculation result and the measurement result is within the allowable value. It is judged whether it is outside the allowable value. In addition, what is necessary is just to prescribe | regulate the tolerance of an error.

  If the inverse problem analysis unit 70 determines in step S504 that the error is within the allowable value, the assumed distribution of the optical characteristic parameters is taken as a solution, and the series of processing ends.

  On the other hand, if it is determined in step S504 that the error is outside the allowable value, the inverse problem analysis unit 70 executes the process of step S501 again. That is, the inverse problem analysis unit 70 again assumes the distribution of the absorption coefficient μa (r) and the converted diffusion coefficient μs ′ (r) based on the error in step S501, and executes the processing from step S502.

  This series of processing is repeatedly executed until the error between the calculation result and the measurement result falls within the allowable value.

  The inverse problem analysis unit 70 generates reconstructed image information based on the optical characteristic parameters μa (r) and μs ′ (r) obtained by the above processing, and sends the information to the tomographic image information generation unit 80. send.

  This process is executed when the near-infrared laser wavelength of the light emitting / receiving block is the first wavelength and the second wavelength, respectively. Therefore, the inverse problem analysis unit 70 sends the reconstructed image information based on the optical characteristic values μa (r) and μs ′ (r) corresponding to the first wavelength and the second wavelength to the tomographic image information generation unit 80. It becomes.

  Then, the tomographic image information generation unit 80 generates tomographic image information that presents the blood volume, oxygen concentration, and the like in the living tissue with luminance and hue based on the reconstructed image information corresponding to the first wavelength and the second wavelength. Generate.

  Here, it is described that the tomographic image information generation unit 80 generates the tomographic image information based on the reconstructed image information corresponding to the first wavelength and the second wavelength, but the present invention is not limited to this.

  That is, tomographic image information can be generated based on the reconstructed image information at each wavelength according to the type of wavelength output by the near-infrared laser.

  Next, the procedure in which the inverse problem analysis unit 70 generates reconstructed image information by the processing method of the present invention will be described with reference to FIG. The flowchart in FIG. 5B includes steps S505 to S509 in addition to steps S501 to S504 executed in the flowchart in FIG.

  First, the inverse problem analysis unit 70 acquires the biometric reference information generated by the biometric reference information generation unit 130 in step S505. Note that the biometric reference information generation unit 130 generates biometric reference information as follows.

  That is, as described above, the two-dimensional blood vessel information generated by the first visualization information acquisition unit 10 is determined by the two-dimensional blood vessel information storage unit 30 at each line of the two-dimensional blood vessel information and the position where the tomographic image information is generated. Stored in an associated form.

  The position for generating the tomographic image is determined by the position of the second light source light emitting / receiving array unit 40, and the positional relationship is determined from the near-infrared / visible composite image shown in FIG. .

  The biological reference information generation unit 130 acquires these pieces of information from the two-dimensional blood vessel information storage unit 30, and in the arm 150, the biological reference information such as the position and thickness of the blood vessel corresponding to the position where the tomographic image information is generated. Is generated.

  Next, in step S506, the inverse problem analysis unit 70 determines whether reconstructed image information for the arm 150 has already been generated during a series of apparatus operations. If the inverse problem analysis unit 70 determines that the reconstructed image information has not yet been generated, the process proceeds to step S501.

  On the other hand, if the inverse problem analysis unit 70 determines that the reconstructed image information has already been generated, in step S507, based on the reconstructed image information corresponding to each wavelength already generated in step S507. The acquired biometric reference information is corrected.

  Next, in step S501, the inverse problem analysis unit 70 assumes the distribution of the absorption coefficient μa (r) and the converted diffusion coefficient μs ′ (r), which are optical characteristic parameters, based on the biometric reference information.

  The biometric reference information includes information such as the position and thickness of the blood vessel corresponding to the position where the tomographic image information is generated, as described above. Therefore, the optical characteristic parameters assumed based on these biological reference information have higher accuracy than the conventional processing method.

  If reconstructed image information has already been generated, in addition to information such as the position and thickness of the blood vessel corresponding to the position at which tomographic image information is generated, the actually generated reconstructed image information is also considered. Based on the corrected biometric reference information, an optical characteristic parameter is assumed. For this reason, the optical characteristic parameter has higher accuracy than that assumed based on the biological reference information before correction.

  And the inverse problem analysis part 70 performs sequentially the process of step S502-S504 similar to Fig.5 (a).

  Next, when it is determined in step S504 that the error is outside the allowable value, the inverse problem analysis unit 70 executes the process of step S501 again. On the other hand, if the inverse problem analysis unit 70 determines that the error is within the allowable value in step S504, the process proceeds to step S508.

  As described above, the inverse problem analysis unit 70 determines the distribution of the absorption coefficient μa (r) and the reduced diffusion coefficient μs ′ (r) based on the biological reference information in step S501, unlike the conventional processing method. Assumes. Therefore, these assumed distributions are very accurate compared to the distribution assumed by the conventional processing method.

  Therefore, the number of iterations of the convergence processing loop until the error between the calculation result and the measurement result falls within the allowable value can be greatly reduced. Therefore, compared with the conventional processing method, the processing circuit scale can be reduced and the processing time can be reduced. Shortening is possible.

  Next, in step S508, the inverse problem analysis unit 70, as described above, reconstructed images based on the optical characteristic values μa (r) and μs ′ (r) corresponding to the respective wavelengths obtained by the above processing. Information is sent to the tomographic image information generation unit 80.

  Then, as described above, the tomographic image information generation unit 80 generates tomographic image information that presents the blood volume, oxygen concentration, and the like in the living tissue with luminance and hue based on the reconstructed image information corresponding to each wavelength. To do.

  Next, in step S509, the inverse problem analysis unit 70 determines whether the second light source emission / light reception array unit 40 has moved in order for the tomographic image information generation unit 80 to generate the next tomographic image information. to decide.

  As described above, the measurement site is changed by moving the second light source emission / light reception array unit 40. The tomographic image information generation unit 80 generates a plurality of tomographic image information corresponding to each of the plurality of lines by changing the measurement site. As a result, the tomographic image information generation unit 80 can generate tomographic image information corresponding to the entire range of the portion surrounded by the dotted line on the skin of the arm 150 illustrated in FIG.

  If the inverse problem analysis unit 70 determines in step S509 that the second light source emission / light reception array unit 40 has moved, the process returns to step S505 and executes a series of processes again. Then, the tomographic image information generation unit 80 similarly generates the next new tomographic image information.

  On the other hand, if the inverse problem analysis unit 70 determines in step S509 that the second light source emission / light reception array unit 40 has not moved, the inverse problem analysis unit 70 regards that generation of necessary tomographic image information has ended, The process ends.

  Next, the tomographic image information accumulation unit 100 classifies and stores the plurality of tomographic image information obtained as described above for each tomographic image information.

  Next, with respect to the information processing that associates a predetermined part of the two-dimensional blood vessel information with the tomographic image information corresponding to the predetermined part and the correction process of the two-dimensional blood vessel information performed by the composite image information generation unit 110, FIG. Will be described with reference to FIG. FIG. 6 is a schematic diagram in which the 3D image information obtained by the information processing and the 2D blood vessel information obtained by the correction process are displayed as images.

  First, the information processing performed by the composite image information generation unit 110 will be described. The composite image information generation unit 110 acquires the two-dimensional blood vessel information stored by the two-dimensional blood vessel information storage unit 30 and the tomographic image information stored by the tomographic image information storage unit 100.

  The composite image information generation unit 110 then overlaps a specific portion of the blood vessel in the two-dimensional blood vessel information with a blood vessel portion included in the tomographic image information corresponding to the specific portion of the plurality of tomographic image information. And this synthesis is performed on each part of the blood vessel.

  The composite image information generation unit 110 generates three-dimensional blood vessel information by performing such information processing. Then, as illustrated in FIG. 6A, the three-dimensional blood vessel information is displayed as an image as a three-dimensional composite image by the biological information display unit 120.

  Next, two-dimensional blood vessel information correction processing performed by the composite image information generation unit 110 will be described. The composite image information generation unit 110 performs correction processing in addition to the generation of three-dimensional blood vessel information by the above-described information processing. The information process and the correction process are performed independently.

  The composite image information generation unit 110 calculates the luminance and hue of the blood vessel part included in the tomographic image information corresponding to the specific part of the plurality of tomographic image information for the specific part of the blood vessel in the two-dimensional blood vessel information. Hue processing is performed with reference. And this hue process is performed with respect to each site | part of the blood vessel.

  The composite image information generation unit 110 generates corrected two-dimensional composite image information by performing such correction processing. Then, as illustrated in FIG. 6B, the corrected two-dimensional composite image information is displayed as a two-dimensional composite image by the biological information display unit 120.

  The three-dimensional composite image information displayed in FIG. 6A obtained as described above is different from the conventional one, and the information processing of the two-dimensional blood vessel information and the tomographic image information is performed, so that the blood vessel becomes three-dimensional. Displayed three-dimensional composite image information can be obtained, and furthermore, a blood vessel of a living body can be clearly discriminated from the difference in luminance and hue.

  In addition, unlike the conventional case, the two-dimensional composite image information displayed as an image in FIG. 6B is tomographically added to the blood vessel by performing correction processing of the two-dimensional blood vessel information using the tomographic image information. Therefore, similarly, a blood vessel of a living body can be clearly discriminated from the difference in luminance and hue.

  Therefore, by generating 3D composite image information and 2D composite image information based on 2D blood vessel information and tomographic image information, it is possible to easily and accurately visualize biological information such as the position, thickness, and direction of blood vessels. Can do. Furthermore, each blood vessel can be accurately identified even with respect to intersecting blood vessels that could not be discriminated so far only with the two-dimensional blood vessel information.

  In addition, in order to visualize the blood vessel, the image information displayed on the biological information display unit 120 may be either two-dimensional synthetic image information or three-dimensional synthetic image information.

  In the above description, the information processing and the correction processing in the case where the tomographic image information is generated for all of the plurality of lines in which the two-dimensional blood vessel information is generated have been described. However, the present invention is limited to this. It is not a thing.

  That is, tomographic image information corresponding to arbitrary line positions of a plurality of lines is generated, and as a result, a plurality of areas corresponding to a part of a range surrounded by a dotted line on the skin of the arm 150 illustrated in FIG. The tomographic image information may be generated, and the same information processing and correction processing may be performed.

  Then, by displaying the two-dimensional composite image information and the three-dimensional composite image information obtained by performing these processes, the information as described above can be obtained, but the above-described effects can be obtained.

  As described above, according to the first embodiment of the present invention, the biological information presentation device is a tertiary generated based on the two-dimensional blood vessel information of a part to be visualized of the living body and the tomographic image information corresponding to the part. Original composite image information and two-dimensional composite image information can be displayed. As a result, it is possible to obtain a biological information presentation apparatus and a biological information presentation method that can easily and accurately visualize biological information such as the position, thickness, and direction of blood vessels that could not be identified with high accuracy.

  DESCRIPTION OF SYMBOLS 10 Visualization information acquisition part, 11 Near-infrared laser, 12 Lens, 13 Optical filter, 14 Image sensor, 20 Two-dimensional blood vessel information generation part, 30 Two-dimensional blood vessel information storage part, 40 2nd light source light emission / light-receiving array part, 41 Light emission / light reception block, 50 pico-pulse light control unit, 60 time-resolved measurement unit, 70 inverse problem analysis unit, 80 tomographic image information generation unit, 90 light emission / light reception array movable support unit, 100 tomographic image information storage unit, 110 composite image information Generation unit, 120 biological information display unit, 130 biological reference information generation unit, 140 biological information presentation device control unit, 150 arm, 151, 152 blood vessel.

Claims (4)

In order to visualize the inside from the surface of the living body, a first inspection light source and a second inspection light source that irradiate the surface of the living body with near-infrared light, and
The near-infrared light is irradiated from the first inspection light source to the range to be visualized in the living body, the visualized range is photographed using the reflected light of the illuminated near-infrared light, and image information of the photographed range A first visualization information acquisition unit for acquiring
A two-dimensional blood vessel information generation unit that generates two-dimensional blood vessel information for each of a plurality of lines in the region visualized by the image information acquired by the first visualization information acquisition unit;
A second light source that irradiates near-infrared light on one of the plurality of lines from the second inspection light source, and detects the light emitted from the irradiated near-infrared light again on the surface of the living body at a plurality of points. A light emitting / receiving array section;
A time-resolved measurement unit that performs time change measurement of the light detected by the second light source emission / light reception array unit, and calculates a measurement value of the time change measurement of the detected light;
Assuming an initial distribution of optical characteristic parameters in the living body, a calculated value of time change of light is calculated based on the assumed initial distribution of the optical characteristic parameter, and the calculated value and the time-resolved measurement unit calculate By performing a comparison process with the measured value, until the error between the measured value and the calculated value falls within a predetermined allowable value, by adjusting the initial distribution of the optical characteristic parameter and repeating the comparison process, Determining an optical characteristic parameter in which the error falls within an allowable value, and generating an inverse problem analysis unit based on the determined optical characteristic parameter; and
Based on the reconstructed image information generated by the inverse problem analysis unit, a tomographic image information generation unit that generates corresponding tomographic image information on the one line;
The second light source light emitting / receiving array unit, the time-resolved measuring unit, and the inverse problem analysis corresponding to the arbitrary line positions of the plurality of lines where the two-dimensional blood vessel information generating unit has generated the two-dimensional blood vessel information. And the tomographic image information corresponding to the arbitrary line position generated by performing a series of processes by the tomographic image information generation unit, and the two lines of the plurality of lines generated by the two-dimensional blood vessel information generation unit. A composite image information generating unit that generates three-dimensional composite image information and two-dimensional composite image information by performing a composite process based on the three-dimensional blood vessel information;
A biometric information display unit that displays the 3D composite image information and the 2D composite image information generated by the composite image information generation unit;
The composite image information generation unit
A specific portion of the blood vessel in the two-dimensional blood vessel information generated for each of the plurality of lines by the two-dimensional blood vessel information generation unit, and the tomographic image information generated by the tomographic image information generation unit corresponding to the arbitrary line position Among them, by performing synthesis processing so as to overlap each blood vessel portion included in each tomographic image information corresponding to the specific site, to generate three-dimensional composite image information about blood vessels in the two-dimensional blood vessel information,
The tomographic image generated by the tomographic image information generation unit corresponding to the arbitrary line position with respect to a specific portion of the blood vessel in the two-dimensional blood vessel information generated by the two-dimensional blood vessel information generation unit for each of the plurality of lines. By performing hue processing while referring to the luminance and hue of the blood vessel portion included in each tomographic image information corresponding to the specific part of the information, the two-dimensional composite image information about the blood vessel in the two-dimensional blood vessel information is obtained. A biometric information presentation device characterized by generating. The biological information presentation apparatus according to claim 1,
The inverse problem analysis unit assumes an initial distribution of optical characteristic parameters in the living body based on the two-dimensional blood vessel information generated by the two-dimensional blood vessel information generation unit or the reconstructed image information generated by itself. A biometric information presentation device as a feature. The biological information presentation apparatus according to claim 1 or 2,
The second light source light emitting / receiving array section is
Each of the second inspection light source and the photodetector that detects the light emitted from the near-infrared light irradiated by the second inspection light source again on the surface of the living body is installed in pairs. With one or more light emitting / receiving blocks,
Among the one or more light emitting / receiving blocks, the one of the light emitted from the near-infrared light irradiated by the second light source for inspection provided in the first light emitting / receiving block again on the surface of the living body. The biometric information presentation apparatus characterized by detecting with each detector of the said light emission / light reception block. A biological information presentation method executed by a biological information presentation apparatus including a first inspection light source and a second inspection light source that irradiates near-infrared light on the surface of the biological body in order to visualize the inside from the surface of the biological body Because
The near-infrared light is irradiated from the first inspection light source to the range to be visualized in the living body, the visualized range is photographed using the reflected light of the illuminated near-infrared light, and image information of the photographed range A first visualization information acquisition step of acquiring
A two-dimensional blood vessel information generation step for generating two-dimensional blood vessel information for each of a plurality of lines in the region visualized by the image information acquired in the first visualization information acquisition step;
A second light source that irradiates near-infrared light on one of the plurality of lines from the second inspection light source, and detects the light emitted from the irradiated near-infrared light again on the surface of the living body at a plurality of points. A light emitting / receiving array detection step;
A time-resolved measurement step of performing a time change measurement of the light detected in the second light source emission / light reception array detection step, and calculating a measurement value of the detected time change measurement of the light;
Assuming an initial distribution of optical characteristic parameters in the living body, a calculated value of time change of light is calculated based on the assumed initial distribution of the optical characteristic parameter, and calculated in the calculated value and the time-resolved measurement step By performing a comparison process with the measured value, until the error between the measured value and the calculated value falls within a predetermined allowable value, by adjusting the initial distribution of the optical characteristic parameter and repeating the comparison process, An inverse problem analysis step of determining an optical characteristic parameter in which the error falls within an allowable value, and generating reconstructed image information based on the determined optical characteristic parameter;
Based on the reconstructed image information generated in the inverse problem analysis step, tomographic image information generating step for generating corresponding tomographic image information on the one line;
Corresponding to the arbitrary line positions of the plurality of lines when the two-dimensional blood vessel information is generated by the two-dimensional blood vessel information generation step, the second light source emission / light reception array detection step, the time-resolved measurement step, Each of the tomographic image information corresponding to the arbitrary line position generated by performing a series of processes in the inverse problem analysis step and the tomographic image information generation step, and the plurality of lines generated in the two-dimensional blood vessel information generation step A composite image information generating step for generating three-dimensional composite image information and two-dimensional composite image information by performing a composite process based on the two-dimensional blood vessel information;
A biometric information display step for displaying the three-dimensional composite image information and the two-dimensional composite image information generated in the composite image information generation step;
The composite image information generation step includes
A specific portion of the blood vessel in the two-dimensional blood vessel information generated for each of the plurality of lines in the two-dimensional blood vessel information generation step, and the tomographic image information generated corresponding to the arbitrary line position in the tomographic image information generation step. Generating three-dimensional composite image information related to blood vessels in the two-dimensional blood vessel information by performing synthesis processing so that the blood vessel portions included in the respective tomographic image information corresponding to the specific part overlap each other,
A tomographic image generated in correspondence with the arbitrary line position in the tomographic image information generation step with respect to a specific portion of the blood vessel in the two-dimensional blood vessel information generated for each of the plurality of lines in the two-dimensional blood vessel information generation step. By performing hue processing while referring to the luminance and hue of the blood vessel portion included in each tomographic image information corresponding to the specific part of the information, the two-dimensional composite image information about the blood vessel in the two-dimensional blood vessel information is obtained. A biometric information presentation method comprising the steps of:

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