JPH027653B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a device for measuring the degree of redox of an organ in a living body.

[Prior art] This type of device is known from the American specialized paper “Journal”.
of applied physiology” (July 1971)
The paper “Optical
consequences of blood substitution on tissue
oxidation−reduction state microfluorometry
(Optical results of blood exchange in tissue redox state microfluorometry)” (Shigeki Kobayashi
The device disclosed in 1993, et al.) is well known. This device is equipped with a radiation source consisting of a mercury lamp and a filter, and this radiation source consists of two different
It has the function of irradiating organs with light of different wavelengths, namely ultraviolet light (366 nm) and infrared light (720 nm). When an organ is irradiated with ultraviolet light, it produces fluorescence (440−
480 nm) is excited, and this fluorescence is collected by a photoelectric receiver.

Also, after irradiating the organ with infrared rays, a portion of the energy is sent back as a reflected beam and collected by another photoelectric receiver. The device also has a system for recording the output signals of both receivers.

[Problem to be Solved by the Invention] The redox state of an organ is detected by the intensity of the aforementioned fluorescence.

However, changes in the concentration of red blood cells within tissues can disrupt photometric measurements, especially when experiments are performed on in-vivo organs. In fact, as the concentration of red blood cells in the tissue decreases, the amount of recorded fluorescence increases.

The aforementioned change in the intensity of the reflected red light represents the concentration of red blood cells in this tissue.

Through experiments on organs maintained in a constant redox state, Kobayashi, using the device disclosed in the aforementioned paper, found that organs completely depleted of blood and organs with varying red blood cell contents were found. We succeeded in creating a graph and formula that relate the intensity of fluorescent light to the reflected intensity of red light. According to Kobayashi, the results of his study show that it is possible to compensate for fluctuations in fluorescence as a function of red blood cell concentration within the tissue by electronic methods.

The device disclosed in the above-mentioned paper is designed to measure the amplitude of an organ that has been isolated from a living body and artificially perfused, that is, a model of an organ that is far from its physiological state, through experiments that can only be performed in a laboratory. Large, slow and induced NADH/
This is a device for investigating changes in NAD ratio.

An object of the present invention is to provide a device that can accurately measure the degree of redox of an organ in a living body.

[Means for solving the problem] According to the present invention, the above-mentioned object is achieved by
a first laser generator that generates a pulse of infrared radiation having a wavelength equiabsorption of hemoglobin; a second laser generator that receives the first pulse and the second pulse; collecting means for collecting the received first and second pulses at one point; and a second pulse to the organ, and a third pulse of fluorescence emitted from the organ by irradiation with the delivered first pulse and a third pulse of fluorescence emitted from the organ by irradiation with the said delivered second pulse. one end is placed on one point and the other end is placed on one point and the other end receives a fourth pulse reflected from the other end and transmits the received third and fourth pulses to one point. an optical fiber to be placed within the organ; a first detection means for receiving said generated first pulse and detecting the intensity of said first pulse; and said receiving means for receiving said generated second pulse. and a third detection means that receives a third pulse sent to one point and detects the intensity of the third pulse. , a fourth detection means for receiving a fourth pulse sent to one point and detecting the intensity of the fourth pulse; and receiving a fourth pulse from the detected first pulse. and calculating means for calculating the redox degree of the organ based on the received first to fourth pulses, and the collecting means includes:
The optical path of the first collected pulse and the optical path of the second collected pulse are arranged in a straight line along the direction of the first longitudinal axis of the optical fiber at one end of the optical fiber. and the end face of one end of the optical fiber is oriented with respect to the direction of the first longitudinal axis so as to direct portions of the first pulse and the second pulse reflected by the end face of the one end to the outside of the means. The end surface of the other end of the optical fiber is such that the first pulse and the second pulse sent from one end of the optical fiber to the other end of the optical fiber are reflected at the end surface of the other end of the optical fiber. Measurement of the redox degree of an organ in vivo at the other end of the optical fiber, which is tilted with respect to the direction of the second longitudinal axis of the optical fiber such that all parasitic pulses are absorbed into the outer peripheral sleeve portion of the optical fiber. This is accomplished by a device.

[Function] The apparatus for measuring the degree of redox of an organ in a living body according to the present invention includes a second laser generator that generates a second pulse of infrared radiation having an isoabsorption wavelength of hemoglobin, and further includes an optical fiber. The end face of the one end is inclined with respect to the direction of the first longitudinal axis of the optical fiber so as to direct portions of the first pulse and the second pulse reflected from the end face of the one end to the exterior of the means. The end face of the other end of the optical fiber is a parasitic pulse reflected at the end face of the other end of the optical fiber among the first pulse and second pulse sent from one end of the optical fiber to the other end of the optical fiber. The redox state of the organ in the body and the organ concerned are oblique to the direction of the second longitudinal axis of the optical fiber at the other end of the optical fiber so that all of the It is possible to detect the reflected pulse, i.e. the fourth pulse, which is independent of the oxidation state of the blood circulating in the optical fiber, and in addition, it is possible to avoid the detection of parasitic pulses reflected at the end face of the other end of the optical fiber, and Detection of the first pulse and the second pulse reflected from the end face of one end can be avoided, and as a result, the degree of redox of an organ in a living body can be accurately measured.

[Embodiments] Hereinafter, specific embodiments of the apparatus according to the present invention will be described based on the accompanying drawings.

In FIG. 1, pulses 2 of ultraviolet radiation with a wavelength of 337 nm are emitted by a nitrogen laser oscillator 1 as a laser generator along an axis 4 in the direction of the container of the dye laser 3. In FIG. The laser oscillator 1 is excited, for example, by a current wave generated by a discharge in the spark gap and then propagated along a flat excitation line. Dye laser 3
has a container containing diethyloxatricarbocyanine (DOTC) iodide and hexamethylindotricarbocyanine (HITC) in a solvent such as dimethyl-sulfoxide (DMSO).
It is filled with a solvent solution of a mixture obtained by dissolving two types of pigments such as iodide. An optical cavity with two mirrors is provided in the container 3 so as to be able to emit pulses of infrared radiation with a wavelength of 805 nm along an axis 6 perpendicular to the axis 4.

A thin plate-shaped optical means 7 is provided at the exit of the laser oscillator 1.
is arranged at an angle of 45° to the axis 4.
The optical means 7 transmits 10% of the energy of the pulse 2 to the axis 8.
It reflects 90 degrees in the direction and transmits the remaining 90%.
The pulses transmitted in this way are transmitted along the axis 4 in the direction of a cylindrical condenser lens 5 arranged between the optical means 7 and the dye laser 3 . Note that the dye laser 3 and the condensing lens 5 constitute a laser generator that generates an infrared pulse having an equiabsorption wavelength of hemoglobin.

On an axis 9 parallel to the axis 4 is the other end face 10 of an optical fiber 11 whose one end face 12 is connected to an organ 13 in the living body and centered on the axis 9 so that the focal point is located on the end face 10. The condenser lens 14 is placed at a position approximately at the intersection of the axes 8 and 9, and is perpendicular to the optical means 7 with respect to the axis 9.
A thin plate-shaped optical means 15 inclined at 45 degrees; a thin plate-shaped optical means 16 disposed parallel to the optical means 15 substantially at the intersection of the axes 6 and 9; and an optical means 16 arranged parallel to the optical means 16 on the axis 9 and a thin plate-like optical means 17 arranged approximately on the intersection of the reflection axis 18 and the reflection axis 18.
, an optical filter 19 arranged perpendicular to the axis 9, and a photoelectric receiver 20 are arranged in this order.

The optical means 7, the condensing lens 14, and the optical means 15 and 16 constitute the collecting means according to the invention.

The optical fiber 11 includes an optical means 7 and a condensing lens 1
4. Receive at one end the pulse of ultraviolet light and the pulse of infrared light collected by the optical means 15 and 16, and send the two received pulses from the other end to the organ 13; The pulse of fluorescence emitted from the organ 13 by the irradiation of the infrared rays and the pulse reflected from the organ 13 by the irradiation of the emitted infrared rays are received at the other end, and the two received pulses are transferred to the For delivery to a single point, one end is placed on the single point and the other end is placed within the organ 13.

An optical attenuator 21 is arranged on the axis 8 between the optical means 7 and the optical means 15, and a first optical attenuator 21 is arranged after the optical means 15.
A photoelectric receiver 22 is arranged as a detection means.
Photoelectric receiver 22 detects the intensity of the ultraviolet light pulse.

Similarly, on the axis 6 an optical attenuator 23 is arranged between the dye laser 3 and the optical means 16, and after the optical means 16 a photoelectric receiver 2 is arranged as a second detection means.
4 is placed. Photoelectric receiver 24 detects the intensity of the infrared pulses.

A photoelectric receiver 25 is arranged on the shaft 18 , and a filter 26 is arranged between the optical means 17 and the photoelectric receiver 25 .

Optical means 17, photoelectric receiver 25 and filter 2
6 constitutes the third detection means according to the present invention.
The optical filter 19 and the photoelectric receiver 20 constitute the fourth detection means according to the present invention.

The outputs of the four photoelectric receivers 20, 22, 24 and 25 are respectively connected to four inputs 27, 28, 29 and 30 of a processing circuit 31 as calculation means.

FIG. 2 is an explanatory diagram of the processing circuit 31. As is clear from the figure, one end of the branch circuit 32 is connected to the input 30 of the processing circuit 31. In the branch circuit 32, an amplifier 33, an integrator 34, and a sampling circuit 35 are sequentially connected in series following the input 30, and the other end of the branch circuit 32 is connected to one input of a divider circuit 36. One end of a branch circuit 37 is connected to the other input of the division circuit 36, and the branch circuit 37
6, a sampling circuit 38, an integrator 39, and an amplifier 40 are sequentially connected in series. The other end of branch circuit 37 is connected to input 28 of processing circuit 31.

A pulse generator 41 is further connected in branch circuit 37 between input 28 and amplifier 40 .

One end of a branch circuit 42 is connected to the input 27 of the processing circuit 31, and in the branch circuit 42, following the input 27, an amplifier 43, an integrator 44, and a sampling circuit 45 are connected in series.
The other end of branch circuit 42 is connected to one input of divider circuit 46, and the other input of divider circuit 46 is connected to one end of branch circuit 47. The branch circuit 47 includes a sampling circuit 48 , an integrator 49 , and an amplifier 50 which are successively connected in series following the division circuit 46 .
The other end of 7 is connected to the input 29 of the processing circuit 31.

The outputs of the two divider circuits 36 and 46 are respectively connected to two inputs of a multiplexer circuit 51, and the output of the multiplexer circuit 51 is connected to the input of an analog-to-digital converter 52. The output of the analog-to-digital converter 52 is connected to the input of a computer 53, and the output of the computer 53 is connected to the input of a register 54.

The apparatus of this embodiment described above with reference to FIGS. 1 and 2 operates as follows.

First, a laser oscillator 1 emits a pulse 2 of ultraviolet light with a wavelength of 337 nm. Through the optical means 7, 10% of the energy of the pulse 2 is reflected along the axis 8 towards the optical means 15. The optical means 15 is a wavelength
A portion of the 337 nm ultraviolet energy is reflected and the rest is transmitted in the direction of the photoelectric receiver 22. Therefore, the pulse 2 reflected by the optical means 7 is reflected by the optical means 15 in a direction parallel to the axis 9 and is directed to one end face 1 of the optical fiber 11 via the condenser lens 14.
Focus on 0.

Optical means 7 transmit the remaining 90% of the energy of pulse 2 along axis 4. The energy transmitted in this way is transmitted to the dye laser 3 via the condenser lens 5.
The dye laser 3 is focused within the container to excite the dye laser 3. The dye laser 3 then emits an infrared pulse with a wavelength of 805 nm along the axis 6. The optical means 16 has the property of partially reflecting light with a wavelength of 805 nm, so that half of the energy of the pulse sent by the dye laser 3 is reflected along the axis 9, and the remaining half is reflected by the optical means 16 described above. through the photoelectric receiver 2
Head to 4. Since the optical means 15 is transparent to light having a wavelength of 805 nm, the pulse reflected via the optical means 16 is transmitted in the direction of the condenser lens 14 . The pulses thus transmitted are focused through the condenser lens 14 onto a point 109 (see FIG. 4) on the end face 10 of one end of the optical fiber 11.

In reality, it may be considered that both the ultraviolet ray pulse and the infrared ray pulse arrive on the end face 10 at approximately the same time.

For reference, the optical fiber 11 has a diameter of 400 mm.
A micron silica core wire covered with an optical sleeve also made of silica but having a lower refractive index may be used. The optical sleeve may have an outer diameter of 500 microns and may be surrounded by a protective sleeve made of plastic material with an outer diameter of 700 microns. The plastic material selected is one that is sterilizable and does not have a clotting effect on blood. If necessary, it is of course possible to use the optical fiber thus constructed by inserting it into a catheter or hypodermic needle.

The optical fiber 11 emits pulses of ultraviolet light and infrared rays from an end face 10 at one end of the optical fiber 11 to an end face 12 at the other end of the optical fiber 11 in order to irradiate an organ 13 such as the heart of a patient undergoing surgery. Transmit both.

The pulse of ultraviolet light has an average wavelength of 480n within organ 13.
m pulses of blue fluorescence are excited. This pulse of fluorescent light is transmitted by an optical fiber 11 from end face 12 to end face 10 and then passes along axis 9 via a condensing lens 14 and optical means 15 which is transparent to the pulse of fluorescent light at a wavelength of 480 nm. 16 are transmitted sequentially.

The pulse of fluorescence is then reflected by the optical means 17 and transmitted along axis 18 to the photoelectric receiver 25 through a filter 26, which is a bandpass filter that transmits only the pulse of fluorescence.

The energy of the infrared pulses transmitted by the optical fiber 11 to the organ 13 is partially reflected by the organ 13 and sent back through the optical fiber 11 from the end face 12 to the end face 10. The reflected pulse thus sent back then travels along axis 9 via a condensing lens 14 and is transmitted through optical means 15, which is transparent to pulses of infrared radiation with a wavelength of 805 nm. half of this pulse of infrared radiation is then transmitted through optical means 16 in the direction of optical means 17, which, being transparent to this pulse of infrared radiation, also transmits this pulse;
The transmitted infrared pulse also passes through a filter 19, which is a bandpass filter that passes only the infrared pulse emitted by the dye laser 3, and finally reaches the photoelectric receiver 20.

When examining multiple organs of different types, the optical attenuator 21 is used to adjust the intensity of the ultraviolet ray pulse and the infrared ray pulse according to these organs.
and 23 are activated.

In the information processing circuit, a pulse of fluorescent light and a pulse of ultraviolet light emitted from the laser oscillator 1 are converted into signals by branch circuits 32 and 37, respectively, and are converted into signals by a division circuit 36.
calculates the ratio between these two signals, so that at the output of the division circuit 36 a fluorescence signal F is obtained which is independent of the intensity of the laser signal sent out by the photoelectric receiver 22.

Similarly, branch circuits 42 and 47 combine the infrared pulses reflected by the organ with the dye laser 3.
The pulses of infrared rays emitted from the photoelectric receiver 24 are converted into signals, and the ratio between these two signals is calculated by the division circuit 46. As a result, a signal I different from the laser signal sent out from the photoelectric receiver 24 is obtained. Division circuit 4
The output of 6 is obtained.

The aforementioned signals F and I are sent to the multiplexer circuit 51
After passing through an analog-to-digital converter 52, it reaches a computer 53. The calculator 53 has a function of deriving the value Fo from the values F and I according to the following formula Io/I=1+K·1n (Fo/F). In this formula, Io and Fo are the I and F obtained when the blood in the organ is completely eliminated.
K and Io are constants that can be determined in advance by testing.

The value Fo obtained in this way does not change depending on the concentration of red blood cells in the tissue, and represents the redox state of the organ being examined.

The pulse generator 41 includes branch circuits 32, 37, 4
2 and 47, the multiplexer circuit 51 of the processing circuit 31, and the elements of the analog-to-digital conversion circuit 52, each time a laser pulse is emitted from the laser oscillator 1, a predetermined time window is opened. have. The pulse generator 41 therefore has the output of the pulse generator 14, as indicated by the arrow, and each of the aforementioned elements has a control input, also indicated by the arrow.
Each output of the pulse generator 41 is connected to the control input of each element, for example, the output 55 is connected to the connection 56.
is connected to the control input 57 of the amplifier 40 via. These time windows avoid the recording of parasitic signals, in particular the reflected signals of the pulses focused on the end face 10 of the optical fiber 11, by activating each element for a short time in conjunction with the moment when the impulse reaches the element. It is for the purpose of

As shown in FIG. 2, not only the signal Fo but also the signals I and F are recorded in the register 54.

The device of this embodiment described above has many advantages.

The higher intensity of the light emitted by various types of ultraviolet lasers, which operate in the form of pulses with a frequency repeating, for example, between 20 and 120 Hz, allows the amount of fluorescence to be reduced while keeping the average irradiation intensity of the examined organ low. It is possible to increase Under these conditions, the irradiation of the organ may cause an increase in the values to be measured (e.g. NADH/
There is no possibility that the NAD ratio will be disturbed, much less that the tissue will change in quality.

If pulses of the above-mentioned frequencies are emitted repeatedly, a sufficient number of pulses will be emitted each time to obtain accurate measurements when measuring humans (resting heart frequency 1.2 Hz) or animals (rat heart frequency 5 Hz). It is sent to the tissue to be examined during each cardiac cycle.

An excimer or exciplex laser may be used in place of the nitrogen laser to generate pulses of fluorescent light. However, it is preferable to use a nitrogen laser whose wavelength (337 mm) is very close to the absorption peak of NADH, since the signal/noise ratio can be increased.

There are two advantages to using a dye laser as an infrared source. One is that this dye laser can be excited with a fraction of the energy of the pulse emitted by the ultraviolet laser, so that two types of measurement pulses are obtained almost simultaneously: a pulse of ultraviolet light and a pulse of infrared light. Another point is that the aforementioned dye laser can also be adapted to the wavelength of 805 nm, which is referred to as the "isoabsorption" wavelength of hemoglobin. That is, if the wavelength is 805 nm, the reflection coefficient of an organ does not depend on the redox state of this organ or the oxidation state of the blood circulating through the organ.

The information processing circuit has a very short response time, so that all the calculations are completed within a time that is significantly shorter than the time to separate the two types of laser pulses.

A single optical fiber is sufficiently flexible that it can be used, for example, to trace the path of a catheter within a blood vessel. This single optical fiber also has the advantage of having only one interface between the fiber tissues. A single interface between the fiber tissues is preferred when the emitting and receiving interfaces are independent of each other because the energy ratio between the emitting and receiving pulses is increased.

However, problems arise when using a single optical fiber for the transmission of emitted and received pulses. This is because parasitic reflections of these pulses on both end faces of the optical fiber run the risk of erroneous measurements. This problem is particularly complicated when the wavelengths of the emitted and received pulses are the same, such as the reference infrared radiation used in the present apparatus shown in FIG. That is, in this case, parasitic reflections cannot be prevented by a filter during reception.

In another embodiment of the device (not shown), the tip of the optical fiber connecting the organ has a rounded shape, such as a hemispherical shape, to reduce Fresnel parasitic reflections.

In the embodiment of the invention shown in FIG. 1, both ends of the optical fiber are flat and the angle formed by the normal to the exit end face 12 of the optical fiber 11 and the transmission axis of the optical fiber 11 is sufficiently large. Optical fiber 11
The laser pulse transmitted by the optical fiber 11 and reflected by the end face 12 is transmitted to the end face 1 through the optical fiber 11.
There is no transmission in the reverse direction from 2 to end face 10.

This situation is shown in detail in FIG. Third
In the figure, it is assumed that the optical fiber 11 is constituted by a core 101 having a refractive index n ₁ surrounded by a sleeve 102 as an outer peripheral sleeve portion having a refractive index n ₂ smaller than _{n 1} . The normal 103 to the point 104 of the end face 12 on the exit side of the pulse forms an angle C with the transmission axis 105 as the longitudinal axis of the optical fiber 11 . 106 is a cone-shaped beam of laser pulses transmitted by optical fiber 11 and focused at point 104 on end face 12 . Most of the energy of this beam 106 passes through the end face 12;
The organ 13 is irradiated as a beam 115. Bee 1
The remaining energy of 06 is reflected on end face 12 and becomes beam 107. Beam 106 is transmission axis 105
It is clear that an angle smaller than the critical transmission angle A is created in the fiber. Limit transmission angle A
The value of is obtained from the following formula.

cosA=n ₂ /n ₁ It is clear that in the situation as in FIG. 3, the pulses in beam 107 all form an angle with transmission axis 105 that is greater than A. Therefore beam 1
All the pulses in 07 are refracted and sent to the sleeve 102.
As a result, there is no possibility of the light being absorbed into the optical fiber 11 and being sent back toward the end face 10 through the optical fiber 11.
The edge 116 of the beam 106 is aligned with the axis 1 relative to the normal 103.
This state will not change as long as it is located on the same side as 05. Therefore, C>A must exist for the entire beam 107 to be refracted and absorbed into the sleeve.

The optical fiber 11 satisfies this condition.

That is, among the pulse beams emitted from the laser oscillator 1 and the dye laser 3 and transmitted from the end face 10 to the end face 12 via the optical fiber 11, the end face 1
All parasitic pulses reflected at 2 are absorbed into the sleeve 102 of the optical fiber 11. Therefore, such parasitic reflected pulses are transmitted in the opposite direction through the optical fiber 11 and are transmitted through the condensing lens 14 and the optical means 1.
5 and 16 and collected by the photoelectric receivers 20 and 25, the accuracy of the measured value cannot be disturbed.

For example, when the optical fiber 11 is formed of doped silica with a refractive index of n ₁ =1.4585 and pure silica with a refractive index of n ₂ =1.448, the condition C>A becomes C>about 7°.

According to yet another feature of the invention, the condenser lens 1
The angle of incidence of the pulse formed by the axis of the laser pulse focused by the lens 4 and the normal to the end surface 10 of the optical fiber 11 is the same as the pulse reflected by the end surface 10 on the entrance side of the pulse. large enough to be sent back outside.

This condition is shown in detail in FIG. The optical fiber 11 has a core 101 with a refractive index n ₁ and a core 101 with a refractive index n ₂ <
n ₁ sleeve 102. A conical beam 108 having an axis 9 is emitted by the condenser lens 14 (FIG. 1) and is focused at a point 109 on the end face 10 of the optical fiber 11. The point 109 is located on the transmission axis 110 as the longitudinal axis of the optical fiber 11, the axis 9, together with the normal 111 of the end face 10, forming an angle of incidence B of the pulse. A portion of the energy of beam 108 is reflected by end face 10 to form conical beam 1
form 12. In order to satisfy the above-mentioned conditions, the entire beam 112 must be located outside the cone 113, that is, the cone having the point 109 as its apex and the edge of the condenser lens 14 as its base.

If E is an angle that is 1/2 the apex angle of the cone 113 and D is an angle that is 1/2 the apex angle of the cone 108, the above condition is expressed as B>E+D/2.

If such a state is realized, the parasitic reflected pulse reflected at the end face 10 will be transmitted in the opposite direction, transmitted through the condensing lens 14 and the optical means 15 and 16, and then collected by the photoelectric receivers 20 and 25. can be avoided. Average reflection direction 1 on end face 10
It is also possible to arrange an absorber at 14.

It goes without saying that in order for the laser energy to be transmitted effectively into the optical fiber 11 through the end face 10 in as large a quantity as possible, the pulsed beam 108 propagated along the axis 9 must be transmitted along the transmission axis 110. It is necessary to bend the optical fiber 11 within the core thereof. If F is the angle formed by the axis 110 and the normal 111, then the equation n ₃ sinB=n ₁ sinF holds true. where n ₃ represents the refractive index in a particular environment.

As an example, angle B is expressed as 45° in FIG. 4, but in this case, if n ₁ =1.4585, n ₃ =1 and the environment is air, angle F is equal to about 29°.

Instead of the embodiments described above, it is of course possible to use techniques equivalent to the embodiments described above within the scope of the present invention.

For example, the laser beam whose reflection by the organ is used as a reference for determining the redox state of the organ may have any wavelength that does not interfere with the wavelength of the fluorescent light. In that case, the processing circuit 31 must have means to make the necessary corrections to the measurement of the redox state.

In the embodiment of the present invention, the reference laser beam has a wavelength called "isoabstic" as described above.

Among the equiabsorption wavelengths, the following two types are particularly well known. namely, the infrared wavelength of 805 nm emitted by the dye laser 3 of the embodiment of FIG. 1 and the orange wavelength of 585 nm emitted by another type of dye laser.

Dye laser 3 used in the embodiment of FIG.
has the two advantages of emitting pulses with an equiabsorption wavelength of 805 nm and of being able to be excited by a pulse 2 of ultraviolet radiation.

It should further be pointed out that in the embodiment of FIG. Vessel 21
and 23 may not be arranged.

Embodiments of the invention can be used to continuously measure the instantaneous value of the NADH/NAD ratio in vivo.

Embodiments of the present invention may be used primarily to investigate cardiac substitution, and more specifically, pathological changes in cardiac substitution during cardiac surgery. In this case, cardiometabolic testing is performed at the endocardial level, ie, inside the ventricles of the heart, using catheters inserted into either veins or arteries.

Embodiments of the present invention can also be used for metabolic testing of organs other than the heart, such as the brain, liver, and kidneys, for example, when certain drugs have been administered or when neoplastic changes have occurred.

[Effects of the Invention] The apparatus for measuring the degree of redox of organs in a living body according to the present invention includes a second laser generator that generates a second pulse of infrared rays having an equiabsorption wavelength of hemoglobin, and further includes: The end face of the one end of the optical fiber is configured such that the end face of the one end of the optical fiber collects portions of the first pulse and the second pulse reflected by the end face of the one end and directs them outside the means. The end surface of the other end of the optical fiber is inclined with respect to the longitudinal axis direction of the optical fiber, and the end surface of the other end of the optical fiber is used to detect the first pulse and the second pulse transmitted from one end of the optical fiber to the other end of the optical fiber. Because the other end of the optical fiber is inclined with respect to the direction of the second longitudinal axis of the optical fiber so that all parasitic pulses reflected from the end face of the optical fiber are absorbed into the outer circumferential sleeve portion of the optical fiber. A reflected or fourth pulse that is independent of the redox state of the organ in the body and the oxidation state of the blood circulating through the organ can be detected, and in addition, the parasitic pulse reflected at the other end face of the optical fiber can be detected. can avoid detection and can avoid detection of the first pulse and the second pulse reflected from the end face of one end of the optical fiber, so that the degree of redox of the organ in the living body can be accurately measured. obtain

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of an apparatus according to an embodiment of the present invention, FIG. 2 is a block diagram forming a part of the apparatus shown in FIG. 1, and FIGS. It is an enlarged view of. 1...Nitrogen laser oscillator, 3...Dye laser,
5, 14...Condensing lens, 7, 15, 16, 17
... optical means, 11 ... optical fiber, 13 ... organ, 19, 26 ... filter, 10, 12 ... end face of optical fiber, 20, 22, 24, 25 ... photoelectric receiver, 21, 23 ... ...Optical attenuator, 31... Processing circuit, 33, 40, 43, 50... Amplifier, 3
4, 39, 44, 49... Integrator, 35, 38,
45, 48...sampling circuit, 36, 46...
...Division circuit, 51...Multiplexer circuit, 52
...AD converter, 53 ... Calculator, 54 ... Register, 101 ... Core, 102 ... Sleeve, 10
3,111...normal line, 9...axis, 105,110
...Transmission axis.

Claims (1)

[Scope of Claims] 1. A first laser generator that generates a first pulse of ultraviolet light, a second laser generator that generates a second pulse of infrared light having an equiabsorption wavelength of hemoglobin, and a first laser generator that generates a first pulse of ultraviolet light; and the second pulse, and the received first pulse and the second pulse.
collecting means for collecting the collected first and second pulses at one point; receiving the collected first and second pulses at one end and directing the received first and second pulses to the organ from the other end; emitting a third pulse of fluorescence emitted from the organ by irradiation with the emitted first pulse and a fourth pulse reflected from the organ by irradiation with the emitted second pulse; The one end is disposed on the one point and the other end is placed within the organ to receive at the other end and deliver the received third and fourth pulses to the one point. the optical fiber to be placed and the generated first
a first detection means for receiving the generated second pulse and detecting the intensity of the first pulse; and a second detection means for receiving the generated second pulse and detecting the intensity of the second pulse. , third detection means for receiving the third pulse sent to the one point and detecting the intensity of the third pulse; and receiving the fourth pulse sent to the one point. and a fourth detection means for detecting the intensity of the fourth pulse, and for receiving a fourth pulse from the detected first pulse and based on the received first to fourth pulse. calculation means for calculating the degree of redox of the organ, and the collecting means is configured to calculate the redox degree of the organ.
and an optical path of the collected second pulses are configured to be in a straight line along the direction of the first longitudinal axis of the optical fiber at one end of the optical fiber; The end face of the one end is inclined with respect to the direction of the first longitudinal axis so as to direct the portions of the first pulse and the second pulse reflected by the end face of the one end to the outside of the collecting means. and the end face of the other end of the optical fiber reflects the first pulse and the second pulse sent from the one end of the optical fiber to the other end of the optical fiber at the end face of the other end of the optical fiber. redox of an in-vivo organ at the other end of the optical fiber that is inclined with respect to the direction of the second longitudinal axis of the optical fiber such that all parasitic pulses are absorbed into the outer circumferential sleeve portion of the optical fiber; Degree measuring device. 2. The focusing means includes a focusing lens, and the angle of incidence of the focused pulse formed between the axis of the pulse focused by the focusing lens and the normal to the end surface of one end of the optical fiber is such that the angle of incidence of the focused pulse is equal to 1/ of the vertical angle
4, and 1/2 of the angle formed between the normal to the end face of the one end of the optical fiber and the first longitudinal axis.
2. The apparatus of claim 1, wherein the end face of one end of the optical fiber is inclined with respect to the first longitudinal axis such that the end surface of the optical fiber is greater than the sum of . 3. The end surface of the other end of the optical fiber is configured such that the angle formed between the second longitudinal axis and the normal to the end surface of the other end of the optical fiber is larger than a critical transmission angle. 3. A device according to claim 1, wherein the device is inclined with respect to the longitudinal axis of the device. 4. The second laser generator receives the first pulse generated by the first laser generator and generates the second pulse by the first pulse. 4. A device according to any one of claims 1 to 3, comprising an active substance. 5. The apparatus of claim 4, wherein the active material is configured to be excited by the first pulse to generate a pulse with a wavelength of 805 nm. 6. The apparatus of claim 4, wherein the active material is configured to be excited by the first pulse to generate a pulse with a wavelength of 585 nm. 7 said collecting means receives said first pulse generated by said first laser generator and reflects said received first pulse towards said one point and said optical fiber; a first half mirror that passes the third pulse and the fourth pulse from the other end; and a first half mirror that receives the second pulse generated by the second laser generator; a second half mirror that reflects the second pulse toward the one point and allows the third pulse and the fourth pulse from the other end of the optical fiber to pass;
7. The device according to claim 1, wherein one end of the optical fiber, the first half mirror, and the second half mirror are arranged in a straight line. 8 The third detection means receives the third pulse and the fourth pulse that have passed through the second half mirror, and directs the third pulse toward the third detection means. while reflecting the fourth
A third half mirror that allows the pulse of Apparatus according to any one of paragraphs 1 to 7.