JPWO2017010465A1 - Blood vessel determination system - Google Patents

Abstract

A dynamic component such as blood flow in the living tissue is measured without hiding the surface of the living tissue. A first transmission path (8) that transmits a laser beam P irradiated to the living tissue (A) and emits the laser beam P from the emitting end (8a), and a living tissue that includes information on dynamic components in the living tissue (A) ( A second transmission path (9) for receiving and transmitting the scattered light (R) from A) at the incident end (9a) and the laser beam (P) emitted from the emission end (8a) to refract the living body. A medical probe comprising an optical element (10) having a positive power as a whole, which irradiates the tissue (A) and collects the scattered light (R) from the living tissue (A) and receives it at the incident end. (2) A blood vessel determination system comprising: a light detection unit that detects scattered light (R) received at the incident end (9a); and a processor (6) that determines the presence or absence of a blood vessel based on dynamic component information. I will provide a.

Description

  The present invention relates to a blood vessel determination system.

  Conventionally, a laser that irradiates a living body with laser light through an emitted light propagation fiber, detects scattered light from the living body with a photodiode through the scattered light propagation fiber, and measures blood flow by frequency analysis of interference components of scattered light by Doppler shift A blood flow meter is known (for example, refer to Patent Document 1).

JP 2008-278983 A

  However, the laser blood flow meter of Patent Document 1 is a method in which the sensor head is in close contact with the surface of the living body, and during the measurement of blood flow, the living body is hidden by the sensor head, and a blood vessel with a large blood flow is formed. Even if it is discovered, there is an inconvenience that the operator cannot visually recognize the position of the blood vessel.

  The present invention has been made in view of the above-described circumstances, and can measure a dynamic component such as blood flow in a living tissue without hiding the surface of the living tissue, and determine whether or not a blood vessel is present. The purpose is to provide a judgment system.

In order to achieve the above object, the present invention provides the following means.
According to one embodiment of the present invention, a first transmission path that transmits laser light to be irradiated onto a living tissue and emits the laser light from an emission end, and scattered light from the living tissue that includes information on dynamic components in the living tissue. A second transmission path that receives light at the incident end and transmits it, and refracts the laser light emitted from the emission end to irradiate the living tissue, and collects scattered light from the living tissue to collect the incident light. A medical probe including an optical element having a positive power as a whole, which is received at the end, a light detection unit that detects the scattered light received at the incident end, and a blood vessel based on information of the dynamic component A blood vessel determination system including a processor for determining presence or absence.

  According to this aspect, the laser beam emitted from the exit end of the first transmission path is refracted by the optical element having positive power, so that the light flux having a smaller diffusion angle than the state emitted from the exit end It is irradiated to the living tissue. The laser light incident on the living tissue is scattered on the surface and inside of the living tissue, becomes scattered light, is collected by an optical element having a positive power, and is received by the incident end of the second transmission path. Since the received scattered light includes information on the dynamic component in the living tissue, it is possible to measure fluctuations in the living body by frequency analysis of the interference component of the scattered light due to Doppler shift.

  In this case, since the diffusion angle of the laser beam is reduced by the optical element having a positive power, it is possible to irradiate the living tissue with the laser light having a high light density even if the optical element is separated from the living tissue. The intensity of the scattered light received by the incident end can be improved to improve the SN ratio, and the dynamic component in the living tissue can be accurately measured. Therefore, since it is not necessary to cover the surface of the living tissue with the medical probe itself, the operator can measure dynamic components such as blood flow at the position while visually recognizing the surface of the living tissue.

In the said aspect, it is preferable that the said output end and the said incident end are arrange | positioned adjacently.
Since the first transmission path and the second transmission path can be configured to have a sufficiently small diameter, the exit end and the entrance end can be made adjacent to each other to make them sufficiently close to each other. For example, when the first transmission path and the second transmission path are optical fibers, the exit end and the entrance end can be brought close to the diameter of the optical fiber including the cladding.

  As a result, the closer the incident end and the exit end are, the more the main beam of the laser beam emitted from the exit end and the scattered light incident on the entrance end closer to the living tissue side than the optical element. The angle of light can be reduced. As a result, a region where light beams with reduced light beam diameters overlap each other, that is, a distance range between a medical probe capable of measuring a dynamic component such as a blood flow and a living tissue can be secured, thereby improving usability. be able to.

The first transmission path and the second transmission path may be separate cores of a multi-core optical fiber.
In multi-core optical fibers, the clads are shared and the cores are close to each other. Therefore, compared to the case where separate optical fibers are used, the exit end and the entrance end can be brought closer to each other, and the living body can be compared to the optical element. On the tissue side, it is possible to secure a larger region where the laser light beam and the scattered light beam overlap.

In the above aspect, the laser beam and the laser beam emitted from the exit end and the scattered light received by the entrance end are separated from each other toward the optical element. An optical deflecting unit that deflects at least one of the scattered light may be provided.
When the power of the optical element is high, the optical element can be disposed close to the exit end, and the spread of the laser light emitted from the exit end is refracted to a relatively small state, so that Although the light beam diameter can be reduced and the light density can be increased to improve the S / N ratio, the pupil position of the optical element is also close to the optical element, so that the light beam of the laser light when the living tissue is arranged at a position away from the optical element The overlap with the light flux of the scattered light is reduced.

  On the other hand, when the power of the optical element is small, it is necessary to move the optical element away from the exit end, and the pupil position of the optical element is also located away from the optical element. While it is possible to ensure a large overlap with the light beam, the laser beam emitted from the exit end is refracted at a large spread position, so that the beam diameter of the laser beam applied to the living tissue increases and the SN ratio decreases. .

  According to this aspect, at least one of the laser light and the scattered light is deflected in a direction in which the light flux of the laser light and the light flux of the scattered light between the emission end and the incident end and the optical element are separated toward the optical element. Since the position where each light beam passes through the optical element moves in the off-axis direction, the power of the optical element is increased, and the diameter of the laser beam irradiated to the living tissue is suppressed while the optical element is deflected. By shifting the pupil position to the living tissue side, it is possible to ensure a large overlap between the luminous flux of the laser beam and the luminous flux of the scattered light when the biological tissue is arranged at a position away from the optical element. Thereby, detection sensitivity can be improved.

Moreover, in the said aspect, the said optical deflection | deviation part may be a field lens which has the negative power arrange | positioned between at least one of the said output end and the said incident end, and the said optical element.
By doing so, the light beam is simply deflected by the field lens, and the diameter of the laser beam irradiated to the living tissue is suppressed, and the laser beam when the living tissue is arranged at a position away from the optical element. A large overlap between the luminous flux and the scattered luminous flux can be ensured, and the measurement sensitivity can be improved.

In the above aspect, the light deflecting unit may be a prism disposed between at least one of the exit end and the entrance end and the optical element.
By doing so, the light beam of the laser light when the biological tissue is arranged at a position away from the optical element while the light beam is simply deflected by the prism and the diameter of the laser light irradiated to the biological tissue is suppressed. And a large overlap between the scattered light flux and the measurement sensitivity can be improved.

Moreover, in the said aspect, you may grind | polish diagonally so that at least one of the said output end and the said incident end may incline in the direction away from the other toward the front-end | tip.
By doing this, the laser beam from the exit end is emitted so that the laser beam emitted from the exit end and the scattered light incident on the entrance end are directed away from each other toward the optical element. Or the scattered light can be deflected when entering the incident end. Thereby, it is possible to improve the measurement sensitivity even for a living tissue arranged at a position away from the optical element.

In the above aspect, the first transmission path or the second transmission path may be curved so that at least one of the exit end and the entrance end is directed to the opposite side.
By doing so, the laser light flux emitted from the exit end and the scattered light incident on the entrance end can be changed depending on the exit direction of the laser light from the exit end itself or the incident direction of the scattered light incident on the entrance end itself. Light beams can be directed away from each other toward the optical element.

  According to the present invention, it is possible to measure a dynamic component such as a blood flow in a living tissue without hiding the surface of the living tissue and determine the presence or absence of a blood vessel.

It is a typical whole block diagram which shows a measurement system provided with the medical probe which concerns on one Embodiment of this invention. It is a figure which shows the positional relationship of the front-end | tip part of the medical probe of FIG. 1, and the light beam of a 1st laser beam and scattered light. It is a front view which shows arrangement | positioning of the optical fiber for illumination with which the medical probe of FIG. 1 is equipped, and the optical fiber for a detection. It is a front view which shows the multi-core optical fiber with which the modification of FIG. 3 is equipped. It is a figure explaining the relationship between the overlap range of the light beam in the medical probe of FIG. 1, and the center distance of an optical fiber. FIG. 6 is a diagram showing a modification of the medical probe in FIG. 1 and showing the positional relationship between the distal end portion of the medical probe having a field lens having negative power and the luminous flux of the first laser beam and scattered light. . It is a figure explaining the relationship between the overlapping range of the light beam in the medical probe of FIG. 6, and the center distance of an optical fiber. It is a modification of the medical probe of FIG. 1, Comprising: It is a longitudinal cross-sectional view which shows the front-end | tip part of the optical fiber provided with the prism. It is a longitudinal cross-sectional view which shows the front-end | tip part of the optical fiber which changed the direction of the prism of FIG. FIG. 9 is a longitudinal sectional view showing a distal end portion of the optical fiber, which is a modification of the medical probe of FIG. 1 and whose emission end and incidence end of the optical fiber are obliquely polished. FIG. 9 is a longitudinal cross-sectional view showing a distal end portion of an optical fiber that is a modification of the medical probe of FIG. 1 and in which an optical fiber is bent and an emission end and an incident end are arranged obliquely.

A medical probe 2 according to an embodiment of the present invention will be described below with reference to the drawings.
A medical probe 2 according to this embodiment is provided in the measurement system (blood vessel determination system) 1 shown in FIG.
The measurement system 1 includes a medical probe 2 according to the present embodiment, a measurement light source 3 that generates a first laser beam P supplied to the medical probe 2, and a display that generates a second laser beam Q. A light source 4, a light detector (light detection unit) 5 that detects scattered light R received by the medical probe 2, and intensity information of the scattered light R detected by the light detector 5 are processed to obtain a blood vessel B And a processor 6 for determining the presence or absence.

The first laser beam P is a laser beam having a near-infrared or infrared wavelength with a high degree of advancement into the living tissue A.
The second laser light Q is a laser light having a visible wavelength band. Since the biological tissue A is red, in order to improve visibility, the second laser light Q is preferably a laser light having a green or blue wavelength band.

The photodetector 5 is, for example, a photodiode, and outputs a signal having an intensity corresponding to the amount of scattered light R.
The processor 6 obtains a frequency characteristic by performing a fast Fourier transform process on the signal output from the photodetector 5, analyzes the frequency characteristic, determines the presence or absence of the thick blood vessel B, and determines that the thick blood vessel B exists. In such a case, the display light source 4 is activated to supply the second laser light Q to the medical probe 2. In the figure, reference numeral 7 denotes an optical coupler that causes the second laser light Q from the display light source 4 to enter the illumination optical fiber 8 that propagates the first laser light P.

  As shown in FIG. 2, the medical probe 2 according to this embodiment includes an illumination optical fiber (first transmission path) 8 that is connected to the measurement light source 3 and propagates the first laser light P, and light. A detection optical fiber (second transmission path) 9 that is connected to the detector 5 and propagates the scattered light R from the living tissue A, an emission end 8a of the illumination optical fiber 8, and an incidence end 9a of the detection optical fiber 9 And a condensing lens (optical element) 10 having a positive power arranged with a space therebetween.

  The illumination optical fiber 8 includes an exit end 8a orthogonal to the longitudinal axis. The first laser beam P or the second laser beam Q transmitted from the measurement light source 3 or the display light source 4 is emitted from the emission end 8a with a diffusion angle of a predetermined numerical aperture. Yes.

  Further, the detection optical fiber 9 includes an incident end 9a orthogonal to the longitudinal axis. Of the scattered light R from the living tissue A, the scattered light R collected by the condenser lens 10 is incident on the incident end 9a at a convergence angle of a predetermined numerical aperture, and is detected by the detection optical fiber 9. Is propagated to the vessel 5.

  As shown in FIGS. 2 and 3, the illumination optical fiber 8 and the detection optical fiber 9 are attached to the exit end 8a at least in the vicinity of the exit end 8a and the entrance end 9a. The incident end 9a is disposed adjacent to the same plane. Thereby, the laser beams P and Q emitted from the emission end 8a and the scattered light R incident on the incidence end 9a are between the plane where the emission end 8a and the incidence end 9a are arranged and the condenser lens 10. The optical fibers 8 and 9 become light beams along substantially parallel central axes that are close to each other with an interval of about a diameter d.

In the present embodiment, the condenser lens 10 is disposed at a position separated from the plane on which the exit end 8 a of the illumination optical fiber 8 and the entrance end 9 a of the detection optical fiber 9 are disposed by the focal length of the condenser lens 10. Has been. As a result, the laser beams P and Q emitted from the exit end 8a of the illumination optical fiber 8 are refracted by the condenser lens 10 to become a substantially parallel light beam and irradiate the living tissue A. .
On the other hand, only the scattered light R from the living tissue A forms a substantially parallel light beam along a predetermined central axis and enters the condenser lens 10 so as to enter the incident end 9 a of the detection optical fiber 9. It has become.

The operation of the medical probe 2 according to this embodiment configured as described above will be described below.
In order to measure the blood vessel B existing in the living tissue A using the medical probe 2 according to the present embodiment, the medical probe 2 is inserted into the patient's body as shown in FIG. The part is arranged to face the surface of the biological tissue A to be measured with a space therebetween.
At this time, the surface of the living tissue A in the vicinity of the region facing the medical probe 2 is photographed by an endoscope (not shown) separately inserted into the body and displayed on a monitor (not shown).

  In this state, the measurement light source 3 is operated to generate the first laser beam P. The first laser light P generated in the measurement light source 3 is propagated through the illumination optical fiber 8 connected to the measurement light source 3 to the vicinity of the distal end portion of the medical probe 2. The first laser light P propagated by the illumination optical fiber 8 is emitted from the exit end 8a of the illumination optical fiber 8, and is refracted by the condensing lens 10 having a positive power to become substantially parallel light. Then, the living tissue A is irradiated.

  The first laser light P applied to the living tissue A is scattered on the surface and inside of the living tissue A, and the scattered light R collected by the condenser lens 10 enters the incident end 9a of the detection optical fiber 9. Then, it is propagated by the detection optical fiber 9 and detected by the photodetector 5. From the photodetector 5, a signal corresponding to the intensity of the detected scattered light R is output. The output signal is subjected to fast Fourier transform in the processor 6 to obtain frequency characteristics.

  When the large blood vessel B exists in the living tissue A, the scattered light R includes information on the dynamic component of the blood flow in the blood vessel B. Therefore, the average included in the scattered light R due to Doppler shift. The frequency characteristics change so as to increase the frequency. The processor 6 determines that a large blood vessel B exists when the average frequency is higher than a predetermined threshold value, and causes the display light source 4 to emit the second laser light Q.

  The second laser light Q emitted from the display light source 4 is incident on the illumination optical fiber 8 by the optical coupler 7 and is irradiated toward the living tissue A from the emission end 8a. Since the second laser light Q is visible laser light that can be visually recognized by the operator, the operator can recognize the presence of the internal blood vessel B by a color change on the surface of the biological tissue A displayed on the monitor. it can.

  In this case, according to the medical probe 2 according to the present embodiment, the condensing lens 10 having a positive power for the first laser light P diffusing from the emission end 8a of the illumination optical fiber 8 with a predetermined numerical aperture. Is refracted into substantially parallel light, so that even if the distance from the medical probe 2 to the living tissue A is wide, the living tissue A can be irradiated without reducing the light density of the first laser light P. , High intensity scattered light R can be generated.

  By irradiating the biological tissue A with the first laser light P, the scattered light R scattered in the biological tissue A, in particular, the scattered light R that travels to the inside of the biological tissue A and scatters the first laser light P. The intensity is highest in the vicinity of the irradiation region. Since the incident end 9a of the detection optical fiber 9 is arranged as close as possible to the emission end 8a of the illumination optical fiber 8, the first laser light P of the scattered light R from the living tissue A is disposed. Scattered light R that returns along a path substantially equivalent to the luminous flux of is incident on the incident end 9a.

  That is, according to the medical probe 2 according to the present embodiment, by bringing the incident end 9a and the emission end 8a close to each other, the first emitted from the emission end 8a on the living tissue A side from the condenser lens 10 is performed. The angle between the chief ray of the laser beam P and the chief ray of the scattered light R incident on the incident end 9a can be made shallower. Thereby, the irradiation region in the living tissue A of the first laser beam P and the generation region of the scattered light R having high intensity that can be incident on the incident end 9a are overlapped over a wide range at each position in the optical axis direction. Can be made.

  As a result, even if the interval between the living tissue A and the medical probe 2 is changed, it is possible to continue to detect the scattered light R having a relatively large intensity, and to improve the SN ratio and perform highly accurate measurement. There is an advantage. Since it is not necessary to set the distance of the medical probe 2 with respect to the living tissue A strictly, usability can be improved.

  In the present embodiment, the two optical fibers 8 and 9 are adjacent to each other with the side surfaces in close contact with each other, so that the emission end 8a of the illumination optical fiber 8 and the incident end 9a of the detection optical fiber 9 are maximized. However, instead of this, as shown in FIG. 4, the first transmission is performed by the adjacent cores 11 and 12 of the multi-core optical fiber 13 having a plurality of cores 11 and 12 in a common cladding. A path and a second transmission path may be configured. Thereby, compared with the case where the independent optical fibers 8 and 9 are made adjacent, the exit end 8a and the entrance end 9a can be brought closer to each other, and the principal ray of the first laser beam P and the scattered light R can be reduced. The angle with the principal ray of the light beam can be further reduced.

  Moreover, in this embodiment, although the example which employ | adopted the single condensing lens 10 as an optical element which has a positive power was shown, it replaces with this and is equipped with a some lens and the positive power as a whole is shown. You may employ | adopt the lens group which will have.

Further, as shown in FIG. 5, it is preferable that the center-to-center distance Y between the emission end 8a of the first transmission path and the incident end 9a of the second transmission path satisfies the following conditional expression.
Y <(NAi + NAd) × Fp2 / (Xn−Fp) (1)
here,
Fp is the focal length of the condenser lens 10,
NAi is the numerical aperture (NA) of the illumination optical fiber 8,
NAd is the numerical aperture (NA) of the detection optical fiber 9,
Xn is the maximum distance from the probe tip to the object necessary for blood vessel detection.

Conditional expression (1) is obtained from the following conditional expression.
First, the condition that the light flux of the first laser light P and the light flux of the scattered light R overlap at the position of the condenser lens 10 is as follows.
0.5 (Dif + Ddf) <Y <(NAi + NAd) · Fp (2)
It is.
here,
Dif is the diameter of the optical fiber 8 for illumination,
Ddf is the diameter of the detection optical fiber 9.

Further, the relationship between the position X where the two light beams do not overlap and the distance Y between the centers of the optical fibers 8, 9 is
Y = (Di + Dd) .Fp / (2X) = (NAi + NAd) .Fp2 / X (3)
It is.
here,
X is the distance from the pupil position on the living tissue A side of the condenser lens 10 to the position where the two light beams do not overlap,
Di is the beam diameter of the first laser beam P,
Dd is the beam diameter of the scattered light R.

If the length of the region where both light beams overlap is Xw,
Xw = X + Fp (4)
It is.
Here, Xw is a distance from the condenser lens 10 to a position where the two light beams do not overlap.

From conditional expressions (3) and (4),
Y = (NAi + NAd) × Fp2 / (Xw−Fp)
Thus, conditional expression (1) is derived by replacing the length Xw with the maximum distance Xn.

In the present embodiment, the first laser beam P emitted from the emission end 8a is refracted into substantially parallel light by the condenser lens 10, but instead, it is emitted from the emission end 8a. The light may be refracted into light that is diffused at a diffusion angle smaller than that of the first laser light P or convergent light that is close to parallel light.
In addition, the illumination optical fiber 8 and the detection optical fiber 9 may be configured by the same optical fiber. However, in order to detect the scattered light R from a wider range, the detection optical fiber 9 may be an illumination optical fiber. An optical fiber having a numerical aperture greater than 8 may be employed.

  In the medical probe 2 according to the present embodiment, the first laser light P emitted from the emission end 8a is directly refracted by the condenser lens 10 and the scattered light R collected by the condenser lens 10 is reflected. Instead of direct incidence on the incident end 9a, instead of this, as shown in FIG. 6, a field lens having negative power between the exit end 8a and the incident end 9a and the condenser lens 10 is used. A (light deflection unit) 14 may be disposed.

  By doing so, the principal ray of the first laser beam P emitted from the exit end 8a and the principal ray of the scattered light R beam refracted by the condenser lens 10 and incident on the field lens 14 are obtained. Are arranged at an angle so as to spread from the field lens 14 toward the condenser lens 10. As a result, the pupil position of the condenser lens 10 moves to the living tissue A side with respect to the focal position of the condenser lens 10.

  In other words, since the two light beams intersect with each other at a position farther from the condensing lens 10, the positive power of the condensing lens 10 is increased to reduce the light beam diameter, and the living tissue A is irradiated. Even when the light density is increased by suppressing the beam diameter of the first laser light P to improve the SN ratio, the pupil position of the condenser lens 10 is close to the condenser lens 10 and the first laser light P It is possible to prevent the overlapping range of the light flux and the scattered light R from being narrowed. Thereby, there exists an advantage that the detection sensitivity of the scattered light R can be improved and usability can be improved.

When the field lens 14 having negative power is disposed between the exit end 8a and the entrance end 9a and the condenser lens 10, as shown in FIG. 7, the conditional expression (2) is as follows. .
0.5 (Dif + Ddf) <Y <(NAi + NAd−α) · Fp (2) ′
It is.
here,
α is an angle between the principal ray of the first laser light P emitted from the illumination optical fiber 8 and the principal ray of the scattered light R incident on the detection optical fiber 9;
α = | Y / Ff |
It is.
Here, Ff is the focal length of the field lens 14.

The length Xw of the region where both light beams overlap is
Xw = X1 + X2 + Fp
It is.
here,
X1 is the distance from the focal point of the condenser lens 10 on the living tissue A side to the pupil position,
X1 = | α · Fp2 / Y | = | Fp2 / Ff |
X2 is the distance from the pupil position on the living tissue A side of the condenser lens 10 to the position where the two light beams do not overlap. In the figure, β is an angle between the chief ray of the first laser beam P that has passed through the condenser lens 10 and the chief ray of the scattered light R that is incident on the detection optical fiber 9.
Therefore, the length of the region where the light beams overlap by the field lens 14 having negative power can be increased by X1.

  The field lens 14 is disposed at a position that allows both the first laser light P and the scattered light R to pass therethrough. However, the field lens 14 is not limited to this, and passes through at least one of the first laser light P or the scattered light R. You may arrange | position in the position to make.

  Further, instead of the field lens 14 having negative power, a prism 15 as shown in FIGS. 8 and 9 may be employed. By arranging the inclined surface 15a of the prism 15 so as to be inclined with respect to the emission direction from the optical fibers 8 and 9, the first laser light P and the scattered light R are obtained by refraction of light when passing through the inclined surface 15a. The principal rays of both light beams can be deflected so as to spread toward the condensing lens 10, and the same effect as that of the field lens 14 having negative power can be achieved.

  Further, instead of arranging the field lens 14 and the prism 15, the exit end 8 a and the entrance end 9 a of the optical fibers 8, 9 are inclined with respect to the longitudinal axis of the optical fibers 8, 9 as shown in FIG. It may be polished. Thereby, the exit end 8a and the entrance end 9a of the optical fibers 8 and 9 can be formed similarly to the inclined surface 15a of the prism 15 of FIG.

Further, as shown in FIG. 11, the tips of the optical fibers 8 and 9 are curved so that the exit end 8 a and the entrance end 9 a are directed in directions opposite to each other with respect to the longitudinal axes of the optical fibers 8 and 9. May be.
Also by these methods, the same effect as the case where the field lens 14 and the prism 15 are arrange | positioned can be achieved.
The arrangement of the prism 15, the polishing of the exit end 8a or the entrance end 9a, or the bending of the tips of the optical fibers 8 and 9 may be performed at a position where at least one of the first laser light P and the scattered light R passes.

1 Measurement system (blood vessel determination system)
2 Medical probe 5 Photodetector (photodetector)
6 Processor 8 Lighting optical fiber (first transmission line)
8a Emission end 9 Optical fiber for detection (second transmission line)
9a Incident end 10 Condensing lens (optical element)
11, 12 core 13 multi-core optical fiber 14 field lens (light deflection unit)
15 Prism (light deflector)
A biological tissue P first laser beam (laser beam)
R scattered light

Claims (8)

A first transmission path for transmitting a laser beam for irradiating a living tissue and emitting it from the exit end;
A second transmission path for receiving and transmitting scattered light from the living tissue including information on dynamic components in the living tissue at an incident end;
An optical element having a positive power as a whole, which refracts the laser light emitted from the exit end and irradiates the living tissue, collects scattered light from the living tissue and causes the incident end to receive the light. A medical probe comprising:
A light detection unit for detecting the scattered light received at the incident end;
A blood vessel determination system comprising: a processor that determines the presence or absence of a blood vessel based on the information of the dynamic component.   The blood vessel determination system according to claim 1, wherein the exit end and the entrance end are disposed adjacent to each other.   The blood vessel determination system according to claim 1 or 2, wherein the first transmission path and the second transmission path are separate cores of a multi-core optical fiber.   At least one of the laser light and the scattered light is deflected in a direction in which the light flux of the laser light emitted from the emission end and the light flux of the scattered light received by the incident end are separated from each other toward the optical element. The blood-vessel determination system as described in any one of Claims 1-3 provided with the optical deflection | deviation part to perform.   The blood vessel determination system according to claim 4, wherein the light deflection unit is a field lens having a negative power arranged between at least one of the emission end and the incidence end and the optical element.   The blood vessel determination system according to claim 4, wherein the light deflection unit is a prism disposed between at least one of the exit end and the entrance end and the optical element.   The blood vessel determination system according to claim 1 or 2, wherein at least one of the exit end and the entrance end is obliquely polished so as to be inclined in a direction away from the other toward the tip.   The first transmission path or the second transmission path is curved so that at least one of the exit end and the entrance end faces away from the other end. Blood vessel determination system.

Images