Blood vessel visualization device and blood vessel puncture system

Abstract

A blood vessel visualization device (10) and a blood vessel puncture system (30) comprise a device that has an irradiation unit (12) for emitting light from a portion in contact with the skin (100a) of a living body (100), and visualizes a blood vessel inside the living body (100) using light transmitted through the living body (100). The irradiation unit (12) is provided with: a fixed part (18) that is fixed to a target site (101) of the living body (100), and makes surface contact with the skin (100a) of the living body (100); a light source placement region (20) that is provided in the fixed part (18) and is provided in the portion that makes surface contact with the skin (100a) of the living body (100); and a plurality of light sources (24) disposed in the light source placement region (20). The plurality of light sources (24) are mutually different in brightness and / or light distribution angle depending on the position thereof in the light source placement region (20).

Description

[Technical field]

[0001] The present invention relates to a blood vessel visualization device and a blood vessel puncture system that illuminate a living body with light to visualize blood vessels. [Background technology]

[0002] A blood vessel visualization device has been proposed that irradiates a target part of a living body with light and visualizes blood vessels by the light transmitted through the target part. For example, JP 2018-64666 A describes a vein visualization device in which a flexible plate-shaped member on which a plurality of light-emitting elements are arranged is wrapped around an arm, and the arm is irradiated with visible light through the light-emitting elements, making it possible to visually observe veins. Summary of the Invention

[0003] In a device for visualizing blood vessels in a living body using transmitted light, it is desirable to make the image of the blood vessels in the target area stand out under transmitted light of uniform brightness. However, since the target area of ​​the living body, such as an arm or a leg, does not have a uniform thickness, localized brightness and darkness are likely to occur, resulting in localized variations in brightness, making it difficult to distinguish the blood vessels.

[0004] Furthermore, when capturing an image of transmitted light and visualizing blood vessels using an image processing device, local variations in brightness in the image of the target area make it difficult to perform image processing.

[0005] Furthermore, if the light source is arranged over a wide area as in JP 2018-64666 A in order to reduce the variation in brightness of the target area, the amount of light that reaches the imaging element after going around the target area increases, causing the transmitted light near the center of the target area to be obscured, making it difficult to see the blood vessels.

[0006] An object of the present invention is to provide a blood vessel visualization device and a blood vessel puncture system that can visualize images of blood vessels in a target area with uniform brightness.

[0007] One aspect of the disclosure below is a blood vessel visualization device that has an irradiation unit that irradiates light from a contact portion with the skin of a living organism, and visualizes blood vessels inside the living organism with transmitted light that has passed through the living organism, wherein the irradiation unit includes a fixing unit that is fixed to a target site of the living organism and in surface contact with the skin of the living organism, a light source placement area that is provided on the fixing unit and in a portion that is in surface contact with the skin of the living organism, and a plurality of light sources that are arranged in the light source placement area, and wherein the brightness or light distribution angle, or both, of each of the plurality of light sources differs depending on a position within the light source placement area.

[0008] Another aspect is a vascular puncture system having the vascular visualization device of the above aspect and a puncture needle or catheter assembly.

[0009] According to the blood vessel visualization device and blood vessel puncture system of the above aspects, images of blood vessels in a target area can be visualized with uniform brightness. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing the configuration of a blood vessel visualization device according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view of the irradiation unit of FIG. 1 attached to a target part (arm) of a living body. [Diagram 3] 3 is a schematic diagram showing a cross section of an irradiation unit and a target site along line III-III (direction A) in FIG. 2, a light receiving unit, and a display unit. [Figure 4] 4A is a diagram showing the relationship between the position in the A direction in FIG. 3 and the thickness of the target portion, and FIG. 4B is a diagram showing the relationship between the position in the A direction in FIG. 3 and the brightness of the light source. [Diagram 5] 5A is a schematic cross-sectional view taken along line VA-VA (direction B) in FIG. 2, and FIG. 5B is a diagram showing the relationship between the position in direction B in FIG. 5A and the brightness of the light source. [Figure 6] 3 is a cross-sectional view showing an example of the arrangement of light sources according to a modified example of the first embodiment, taken along the direction A in FIG. 2. [Figure 7]FIG. 7A is a schematic cross-sectional view showing a blood vessel visualization device according to the second embodiment, and FIG. 7B is a schematic cross-sectional view showing a blood vessel visualization device according to a modified example of the second embodiment. [Figure 8] FIG. 8A is a side view of a light source according to the third embodiment, and FIG. 8B is a schematic cross-sectional view of an irradiation unit of a blood vessel visualization device according to the third embodiment using the light source of FIG. 8A attached to a target site of a living body. [Figure 9] 13 is a schematic diagram showing a cross section of an irradiation unit, a light receiving unit, and a display unit of a blood vessel puncture system according to a fourth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to preferred embodiments thereof with reference to the accompanying drawings. Note that the dimensional ratios of the drawings may be exaggerated for the sake of explanation and may differ from the actual ratios.

[0012] (First embodiment) As shown in FIG. 1, the blood vessel visualization device 10 includes an irradiation unit 12, a light receiving unit 14, and a display unit 16. The irradiation unit 12 has a flexible plate-like fixed unit 18. The fixed unit 18 is formed in a rectangular shape elongated in the A direction in the figure. A light source placement area 20 is provided in the center of the surface 18a of the fixed unit 18 in the A direction. In addition, abutment parts 22a and 22b are provided on both sides of the light source placement area 20 in the A direction, respectively. As shown in FIG. 2, the fixed unit 18 can be bent to match the shape of a target site 101 (an arm in the illustrated example) of a living body 100. When the abutment parts 22a and 22b are wrapped around the target site 101, the shape is maintained. Then, the fixed unit 18 is fixed so as to be wrapped around the target site 101. At that time, the surface 18a of the fixed unit 18 is in surface contact with the target site 101.

[0013] 1, a plurality of light sources 24 are arranged in the light source installation area 20 on the surface 18a. The light sources 24 are light emitting elements such as light emitting diodes or EL light emitting elements, and are regularly arranged two-dimensionally in the light source installation area 20. The dimension of the light source installation area 20 in the B direction can be the same as the dimension of the fixing part 18 in the B direction.

[0014] 3, the dimension of the light source installation area 20 in the A direction is set so that when the fixing part 18 is wrapped around the target part 101 of the living body 100, the width W2 occupied by the light source installation area 20 is about 40 to 80% of the total width W1 of the wrapped part. The specific value of the width W2 can be appropriately adjusted within the above range according to the optical characteristics (light distribution angle and brightness) of the light source 24. If the width W2 occupied by the light source installation area 20 is smaller than the above ratio, the target part 101 cannot be illuminated with uniform brightness, and brightness varies. If the ratio of the width W2 occupied by the light source installation area 20 is larger than the above value, the amount of light that goes around the side of the target part 101 increases, and the visibility of the blood vessels in the target part 101 decreases.

[0015] The light source 24 may be a light emitting element (e.g., a light emitting diode) as a discrete component bonded to the fixed portion 18. Alternatively, the light source 24 may be a light emitting element as a modular component in which a plurality of light sources 24 are arranged in a plane and integrated, and attached to the light source installation area 20 of the fixed portion 18. As will be described later, the light source 24 has different light irradiation characteristics depending on the position within the light source installation area 20. In this embodiment, the light distribution angle (irradiation angle range L) of each light source 24 within the light source installation area 20 is constant.

[0016] As the light source 24, for example, an infrared light emitting diode that irradiates near-infrared light having a wavelength centered at 700 nm or more and 2500 nm or less, preferably 700 nm or more and 1400 nm or less, more preferably 780 nm or more and 940 nm or less, can be used. The light source 24 may also be one that emits visible light (not including near-infrared light). The light source 24 may also be one that emits light including both near-infrared light and visible light.

[0017] The light receiving unit 14 may be, for example, a CMOS camera or a CCD camera for visible light or near infrared light. As shown in Fig. 3, the light receiving unit 14 is disposed opposite the light source placement area 20 of the irradiation unit 12 across the target site 101 of the living body 100. The light receiving unit 14 is a camera (imaging unit) that captures an image of the target site 101 based on the transmitted light of the light source 24 that passes through the target site 101 of the living body 100.

[0018] The display unit 16 displays the image of the target site 101 acquired by the light receiving unit 14 on a display screen.

[0019] Next, the shape of the target part 101 of the living body 100 and the light irradiation characteristics of the light source 24 will be described. The target part 101 of the living body 100 is, for example, a human arm as shown in FIG. 2, and can be considered to have a wide elliptical cross section. As shown in FIG. 3, considering the cross section in the A direction, light source 24 emits light at a constant light distribution angle (irradiation angle range L). The light from light source 24 is scattered within the target part 101 of the living body 100, passes through the target part 101 toward the light receiving unit 14, and then passes through surface 101a of the target part 101.

[0020] The light emitted from each light source 24 passes through the target site 101 in a direction generally parallel to a line connecting the light receiving unit 14 and the light source 24 at the center of the light source installation area 20 in the A direction. Therefore, the thickness through which the light passes through the inside of the target site 101 varies depending on the position of the light source 24 in the light source installation area 20. As shown in FIG. 4A, when the shape of the target site 101 is elliptical, the thickness through which the light emitted from the light source 24 passes through the target site 101 is distributed in the A direction as shown. When the thickness through which the light passes through the target site 101 increases, the amount of light absorbed inside the living body 100 also increases, resulting in variations in brightness.

[0021] Therefore, in this embodiment, the brightness (luminous flux [lm]) of each light source 24 is changed according to the position in the A direction, as shown in Fig. 4B. That is, the brightness of the light source 24 is set relatively low near the peripheral portion in the A direction of the light source installation area 20, where the thickness through which the irradiated light passes inside the target site 101 decreases. Meanwhile, the brightness of the light source 24 is set relatively high near the center portion in the A direction of the light source installation area 20, where the thickness through which the irradiated light passes inside the target site 101 increases.

[0022] 5A, when the target site 101 is an arm and has different thicknesses on the distal and proximal sides, the thickness through which the irradiated light passes through the target site 101 changes depending on the position in direction B of the light source installation area 20. Therefore, in this embodiment, the brightness of the light source 24 may be small on the distal side of the light source installation area 20 and large on the proximal side of the light source installation area 20, as shown in FIG. 5B. Depending on the shape of the target site 101, the brightness distribution of the light source 24 in direction B may be reversed from that described above, or there may be no difference in brightness of the light source 24 in direction B.

[0023] 6, instead of changing the brightness (luminous flux [lm]) of the light source 24, the light distribution angle (irradiation angle [sr]) of the light source 24 in the light source installation area 20 may be changed. In this case, the light distribution angle of the light source 24 is increased near the periphery in the A direction of the light source installation area 20 where the thickness through which the irradiated light passes inside the target site 101 decreases. Also, the light distribution angle of the light source 24 is decreased near the center in the A direction of the light source installation area 20 where the thickness through which the irradiated light passes inside the target site 101 increases.

[0024] Furthermore, instead of determining the brightness distribution of each light source 24 in the light source installation area 20 according to the model with an elliptical cross section as described above, it may be set so that the luminance value of transmitted light is constant on the surface 101a facing the light receiving unit 14 of the target site 101. In this case, the luminance distribution of the image of the light receiving unit 14 may be obtained, and a control unit (not shown) may be configured to individually set the brightness or light distribution angle of the light source 24 under conditions where the luminance distribution is constant.

[0025] The blood vessel visualization device 10 of this embodiment provides the following effects.

[0026] The blood vessel visualization device 10 of this embodiment has an irradiation unit 12 that irradiates light from a contact portion with the skin 100a of the living body 100, and visualizes blood vessels inside the living body 100 with transmitted light that has passed through the living body 100. The irradiation unit 12 has a fixing unit 18 that is fixed to a target site 101 of the living body 100 and is in surface contact with the skin 100a of the living body 100. A light source installation area 20 is provided in a portion of the fixing unit 18 that is in surface contact with the skin 100a of the living body 100. A plurality of light sources 24 are provided in the light source installation area 20, and the brightness or light distribution angle or both of the plurality of light sources 24 differ depending on the position within the light source installation area 20.

[0027] According to the above configuration, the brightness or light distribution angle of the light source 24 can be changed between a thick portion and a thin portion through which the irradiated light passes inside the target part 101 of the living body 100. This makes it possible to uniformize the amount of light passing through the target part 101, and suppress variations in the brightness of the surface 101a.

[0028] In the above blood vessel visualization device 10, the brightness or light distribution angle of the light source 24 may be changed according to the thickness of the living body 100 along a direction parallel to a line connecting the light source 24 at the center of the light source installation area 20 and the light receiving unit 14. This configuration can prevent variation in luminance on the surface 101a of the target site 101. In this case, the brightness or light distribution angle of the light source 24 may be obtained by regarding the living body 100 as a cylindrical body with an elliptical cross section.

[0029] In the above blood vessel visualization device 10, the brightness or light distribution angle of each of the multiple light sources 24 may be set so that the illuminance distribution of transmitted light on the surface 101a of the target site 101 of the living body 100 is constant. This configuration can suppress variations in the luminance of the target site 101. In this case, the brightness or light distribution angle of the light sources 24 may be individually adjusted under the control of the control unit based on the image captured by the light receiving unit 14.

[0030] In the above blood vessel visualization device 10, the fixed part 18 is formed in an elongated shape extending in a direction transverse to the target part 101 of the living body 100, and three or more light sources 24 are provided along the long axis of the fixed part 18, with the light source 24 located at the center being the brightest among the light sources 24. According to this configuration, by making the brightness of the light source 24 at the portion where the thickness of the irradiated light passing through the target part 101 of the living body 100 is the greatest, it is possible to suppress variations in the brightness of the surface 101a of the target part 101.

[0031] In the above blood vessel visualization device 10, the fixed part 18 is formed in an elongated shape extending in a direction crossing the target part 101 of the living body 100, and three or more light sources 24 are provided along the long axis of the fixed part 18, and the light distribution angle of the light source 24 provided on the outside in the long axis direction may be larger than the light distribution angle of the light source 24 arranged at the center in the long axis direction. According to this configuration, by widening the light distribution angle of the outer light source 24 where the thickness of the irradiated light passing through the target part 101 of the living body 100 becomes thinner, it is possible to suppress variation in brightness of the surface 101a of the target part 101.

[0032] In the above blood vessel visualization device 10, the fixing part 18 may be deformable according to the shape of the target site 101 of the living body 100. According to this configuration, the fixing part 18 can be fixed to the target site 101 by wrapping it around the target site 101.

[0033] The blood vessel visualization device 10 may be provided with a light receiving unit 14 that captures an image of transmitted light appearing on the surface 101a of the target site 101 of the living body 100. With this configuration, light other than visible light can be used as transmitted light. Also, a transmitted image of the living body 100 can be obtained even with weak transmitted light that cannot be seen by the naked eye. This configuration may also have a display unit 16 that displays the image captured by the light receiving unit 14. The display unit 16 allows the image captured by the light receiving unit 14 to be viewed on the spot.

[0034] In the above blood vessel visualization device 10, the irradiation unit 12 and the light receiving unit 14 may be disposed opposite to each other across the target site 101 of the living body 100. According to this configuration, the blood vessels can be visualized by capturing transmitted light passing through the target site 101 of the living body 100 with the light receiving unit 14.

[0035] In the above blood vessel visualization device 10, the light source 24 may irradiate near-infrared light. According to this configuration, by using near-infrared light that has high transmittance to the living body 100, a clearer visualized image of the blood vessels can be obtained.

[0036] In the above blood vessel visualization device 10, the wavelength of the near-infrared light emitted by the light source 24 may be 700 nm or more and 2500 nm or less, preferably 700 nm or more and 1400 nm or less, and more preferably 780 nm or more and 940 nm or less. Near-infrared light of this wavelength is more absorbed by blood than by biological tissue (target site), and is therefore suitable for visualization of blood vessels.

[0037] Second embodiment As shown in Fig. 7A, the blood vessel visualization device 10A of this embodiment includes an illuminant 26 instead of the light receiving unit 14 and the display unit 16. The illuminant 26 is a plate-shaped member in which a transparent plate-shaped substrate such as glass is coated or impregnated with a phosphor. Near-infrared light transmitted through biological tissue is converted into infrared light of a specific wavelength suitable for imaging and emitted. The illuminant 26 is disposed near the living body 100 so as to face the irradiating unit 12 and the living body 100 with the illuminant 26 sandwiched between them.

[0038] The light emitter 26 emits infrared light of a specific wavelength with a luminance corresponding to the intensity of the near-infrared light transmitted through the living body 100, thereby making it possible to visualize blood vessels near the skin 100a of the living body 100.

[0039] The light emitting body 26 may be arranged so as to be wrapped around the surface 101a of the target site 101, as shown in FIG. 7B.

[0040] The blood vessel visualization device 10A of the present embodiment includes a light emitter 26 that converts transmitted light (near-infrared light) appearing on the surface 101a of the target site 101 of the living body 100 into light of a different wavelength (visible light) and displays the light. This makes the light receiving unit 14 and the display unit 16 unnecessary even when near-infrared light is used, and allows the device configuration to be simplified.

[0041] Third embodiment As shown in Figures 8A and 8B, in the blood vessel visualization device 10B of this embodiment, a transparent convex portion 28 is provided at a contact portion of the light source 24 of the irradiation unit 12 with the living body 100. In the blood vessel visualization device 10B of this embodiment, the same components as those in the blood vessel visualization device 10 of the first embodiment are denoted by the same reference numerals and detailed description thereof will be omitted. Also, in Figure 8B, the light receiving unit 14 and the display unit 16 are not shown.

[0042] The shape of the convex portion 28 is not particularly limited, but is formed in a hemispherical shape with the same diameter as that of the light source 24. The convex portion 28 is formed of a flexible material whose refractive index for the wavelength of the light irradiated by the light source 24 is equivalent to the refractive index of the biological tissue (target site) at that wavelength. When the light irradiated by the light source 24 irradiates near-infrared light, the convex portion 28 can be formed of a flexible silicone resin. In addition, since the refractive index of the convex portion 28 is close to that of the living body 100, reflection on the skin 100a of the living body 100 can be suppressed.

[0043] 8B, when the fixing part 18 is attached to the target site 101 of the living body 100, the skin 100a of the living body 100 is deformed into a concave shape by the convex part 28, and the convex part 28 is pressed into the target site 101. This allows the light from the light source 24 to be more efficiently irradiated onto the target site 101 of the living body 100. In addition, because the amount of light that goes around the target site 101 is reduced, the noise components that drown out the transmitted light can be reduced, and a clearer visualized image of the blood vessels can be obtained.

[0044] In the blood vessel visualization device 10B, the light source 24 has a protrusion 28 at a portion where it abuts against the skin 100a of the living body 100. With this configuration, light is efficiently propagated from the portion where the protrusion 28 is pressed into the living body 100. In addition, it is possible to suppress the generation of light that goes around the target site 101. In addition, since the thickness through which light passes through the target site 101 is reduced by the amount that the protrusion 28 is pressed in, a clearer fluoroscopic image can be obtained.

[0045] In the blood vessel visualization device 10B, the convex portion 28 may be made of a soft, light-transmitting material. With this configuration, a clearer visualized image of the blood vessels can be obtained.

[0046] (Fourth embodiment) In this embodiment, a blood vessel puncture system 30 will be described. As shown in Fig. 9, the blood vessel puncture system 30 includes the blood vessel visualization device 10 of Fig. 1 and a needle module 32. Here, a description of the blood vessel visualization device 10 will be omitted.

[0047] The needle module 32 is, for example, an indwelling needle or catheter assembly to be placed in a blood vessel. The needle module 32 has a needle tube 34 and a sharp needle tip 36 provided at the tip of the needle tube 34. The needle tube 34 is made of a metal material such as stainless steel, and is composed of a material with low transmittance for near-infrared light and infrared light. For this reason, the needle tube 34 of the needle module 32 is displayed as a black portion on the display unit 16.

[0048] Needle module 32 is disposed in the space between light receiving unit 14 and target site 101 of living body 100. A user can perform a procedure of puncturing a blood vessel while light receiving unit 14 captures a fluoroscopic image of target site 101 of living body 100.

[0049] As described above, the blood vessel puncture system 30 of this embodiment includes the blood vessel visualization device 10 and the puncture needle or catheter assembly (needle module 32).

[0050] According to the above configuration, the blood vessel can be inserted with a puncture needle or a catheter assembly while accurately grasping the position of the blood vessel using the blood vessel visualization device 10. The blood vessel visualization device 10 can visualize a wide range with uniform brightness, making it easy to find a blood vessel suitable for puncture. Therefore, the blood vessel puncture system 30 makes it easy to insert the puncture needle or the catheter assembly into the blood vessel.

[0051] Although the present invention has been described above with reference to preferred embodiments, it goes without saying that the present invention is not limited to the above embodiments, and various modifications are possible without departing from the spirit of the present invention.

Claims

1. A blood vessel visualization device having an irradiation unit that irradiates light from a contact portion with the skin of a living body, and visualizes blood vessels inside the living body with transmitted light that has passed through the living body, the irradiation unit comprising: A fixing part that is fixed to a target site of the living body and is in surface contact with the skin of the living body; A light source placement area is provided on the fixing part and is provided in a portion that comes into surface contact with the skin of the living body; A plurality of light sources arranged in the light source arrangement area; a light receiving unit that captures an image of the transmitted light appearing on a surface of the target part of the living body, The brightness or the light distribution angle, or both, of each of the plurality of light sources can be changed depending on the position within the light source arrangement area, The brightness of the light source is set to be large or the light distribution angle is reduced according to an increase in the thickness of the living body along a direction parallel to a line connecting the light source at the center of the light source arrangement area and the light receiving unit. Blood vessel visualization device.

2. 2. The blood vessel visualization device according to claim 1, wherein the brightness or light distribution angle of each of the plurality of light sources is set so that the illuminance distribution of the transmitted light on the surface of the target part of the living body is constant.

3. 3. The blood vessel visualization device according to claim 1 or 2, wherein the fixed part is formed in an elongated shape extending in a direction crossing the target site of the living body, three or more light sources are provided along the long axis of the fixed part, and the light source located at the center among the light sources has the greatest brightness.

4. 4. The blood vessel visualization device according to claim 1, wherein the fixing part is deformable in accordance with a shape of a target part of the living body.

5. 5. The blood vessel visualization device according to claim 4, wherein the fixing part is fixed to the skin of the living body so as to be wrapped around the target site of the living body.

6. 6. The blood vessel visualization device according to claim 5, further comprising a display section for displaying the image captured by the light receiving section.

7. 7. The blood vessel visualization device according to claim 1, wherein the irradiating unit and the light receiving unit are arranged opposite each other with a target site of the living body interposed therebetween.

8. 8. The blood vessel visualization device according to claim 1, wherein the fixed part is formed in an elongated shape extending in a direction crossing a target site of the living body, three or more of the light sources are provided along a long axis of the fixed part, and a light distribution angle of the light source provided on the outside in the long axis direction is larger than a light distribution angle of the light source arranged at the center in the long axis direction.

9. 9. The blood vessel visualization device according to claim 1, further comprising an illuminator that converts the transmitted light appearing on the surface of the target site of the living body into light of a different wavelength and displays it.

10. 10. The blood vessel visualization device according to claim 1, wherein the light source has a convex portion at a portion that comes into contact with the skin of the living body.

11. 11. The blood vessel visualization device according to claim 10, wherein the protrusion is made of a soft material that transmits light.

12. 12. The blood vessel visualization device according to claim 1, wherein the light source irradiates near-infrared light.

13. 13. The blood vessel visualization device according to claim 12, wherein the wavelength of the near-infrared light emitted by the light source is not less than 700 nm and not more than 2500 nm.

14. The blood vessel visualization device according to any one of claims 1 to 13, a puncture needle or catheter assembly; A vascular puncture system having

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