A fluorescence detection device for tissue that is insensitive to ambient light

Abstract

The application discloses a fluorescence detection device for tissues insensitive to ambient light, which comprises an excitation light unit, a signal acquisition unit and a data processing unit, the excitation light unit emits light with a spectral range of lambda a to the tissues to be detected; the signal acquisition unit receives the light with a fluorescence wave band lambda b and a fluorescence outer wave band lambda c returned by the tissues to be detected and filters out the light with an excitation light wave band lambda a ; the data processing unit acquires the corresponding spectra H b and H c of the fluorescence wave band lambda b and the fluorescence outer wave band lambda c under the condition that the excitation light unit is turned off and acquires the corresponding spectra S b and S c of the fluorescence wave band lambda b and the fluorescence outer wave band lambda c under the condition that the excitation light unit is turned on, obtains a correction coefficient alpha by S c / H c , acquires an ambient correction signal according to the formula H x =H b * alpha and performs result determination; the application has the advantages that the detection process is simple and the stability and accuracy of in vivo fluorescence detection are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biomedical engineering, and more particularly to a fluorescence detection device for tissues insensitive to ambient light. BACKGROUND

[0002] With the development of fluorescence detection technology, biological fluorescence detection technology has been widely used in the field of life science, medical research, etc., especially in vivo fluorescence detection technology can directly detect the activity of living biological cells and gene behavior, providing convenience for life science research and medical treatment. Fluorescence detection includes exogenous fluorescence marker fluorescence and autologous fluorescence, using sensitive optical detection instrument, observing the occurrence and development of diseases in vivo, tumor growth and metastasis, gene expression and other biological processes, and positioning of glands, tissues and tumors.

[0003] Compared with in vitro detection, this technology has the advantages of high detection sensitivity and simple operation, and has the characteristics of non-invasive, rapid and real-time for gland and tissue recognition, avoiding unnecessary surgical resection and other damaging operations. However, in vivo fluorescence detection, especially in vivo tissue autologous fluorescence detection, has the defects of weak fluorescence signal and easy interference by ambient light, which affects the stability and accuracy of the measurement results. The commonly used method is to create a dark box device to block the influence of ambient light, but in some cases, such as during surgery, it is difficult to achieve a dark box environment, limiting the application of in vivo fluorescence detection in tissue and gland recognition.

[0004] To avoid the interference of ambient light, Chinese Patent Publication No. CN111343910A proposes a design of heterodyne detection technology. After a modulator 100 generates a modulated signal of a specific frequency, a lock-in amplifier is used to extract the signal, which increases the cost and complexity of the system. Chinese Patent Publication No. CN112826452A designs a parathyroid gland recognition system based on modulated excitation light. The autofluorescence is converted into an electrical signal by a photoelectric sensor and then collected. The fluorescence signal amplitude at the modulation frequency is extracted by Fourier transform to remove the interference of direct-current shadow lamp and power-frequency alternating-current ambient light. The process is complex and does not consider the interference of natural light, which affects the stability and accuracy of the measurement results. Chinese Patent Publication No. CN110376177A discloses a nicotinamide adenine dinucleotide fluorescence spectrum detection device and use method. The blood flow control unit controls the blood flow rate. The excitation light source and the calibration light source in the excitation and calibration unit emit excitation light and calibration light under the control of the second controller. The probe transmission optical fiber is used to transmit the excitation light source and the calibration light source after scattering and absorption at the detection position. The data processing unit is used to receive the spectrum signal measured by the spectrum detection unit and calculate and correct the measured spectrum signal. However, the correction process does not consider eliminating the interference of natural light and ambient light, which affects the stability and accuracy of the measurement results. SUMMARY

[0005] The technical problem to be solved by the present application is that the existing fluorescence detection device has a complex detection process and does not consider eliminating the interference of natural light and ambient light, which affects the stability and accuracy of the measurement results.

[0006] The present application solves the above technical problems by the following technical means: a fluorescence detection device for tissues insensitive to ambient light, comprising an excitation light unit, a signal acquisition unit and a data processing unit. The excitation light unit emits excitation light with a spectrum range of λ a to the tissue to be measured. The signal acquisition unit receives the light returned by the tissue to be measured in the fluorescence wave band λ b and the fluorescence outer wave band λ c , and filters out the light in the excitation wave band λ a . The data processing unit acquires the corresponding spectra H b and H c of the fluorescence wave band λ b and the fluorescence outer wave band λ c in the condition of closing the excitation light unit, and acquires the corresponding spectra S b and S c of the fluorescence wave band λ b and the fluorescence outer wave band λ c in the condition of opening the excitation light unit. a b c a b c b c b c b cc / H c The correction coefficient alpha is obtained according to formula H x = H b The environmental correction signal is obtained according to formula S = S b -H x = S b -H b The fluorescent correction signal is obtained according to the corrected fluorescent signal, and the result is determined.

[0007] The present application first measures under the environment light and the background light, obtains the environment light characteristics (spectra H b and H c ), and measures the fluorescent wave band and the light signal outside the fluorescent wave band range (spectra S b and S c ) under the excitation light source, then obtains the correction coefficient based on the measurement results, obtains the environmental correction signal by using the correction coefficient, considers the environmental correction signal to correct the fluorescent signal to obtain the fluorescent correction signal, finally determines whether it is the target tissue, the whole detection process is simple, considers eliminating the interference of natural light, environment light and the like, avoids the correction error caused by the change of the environment light, is helpful to realize the in-vivo fluorescent detection which is not sensitive to the environment light, and improves the stability and accuracy of the in-vivo fluorescent detection.

[0008] Further, the excitation light unit comprises a light source and a first optical filter, the light source is opposite to the first optical filter, and the light source emits light with a spectral range of lambda a which is converged into the first optical fiber after passing through the first optical filter.

[0009] Further, the fluorescent detection device for the tissue which is not sensitive to the environment light further comprises a probe, the probe is aimed at the tissue to be measured, the probe is connected with the first optical fiber, and the probe is connected with the signal acquisition unit through the second optical fiber.

[0010] Further, the signal acquisition unit comprises a photoelectric detector and a second optical filter, the signal exit of the second optical fiber is opposite to the second optical filter, the second optical filter is opposite to the photoelectric detector, and the photoelectric detector simultaneously receives the light with the fluorescent wave band lambda b and the fluorescent wave band lambda c returned by the tissue to be measured.

[0011] Further, the second optical filter is a notch optical filter.

[0012] Further, the photoelectric detector is a spectrometer.

[0013] Further, the signal collecting unit comprises two second filters and two photoelectric detectors, the signal exit of the second optical fiber has two, respectively facing two second filters, two second filters respectively facing a photoelectric detector, wherein a group of second filters and photoelectric detectors are used for detecting the light of fluorescent wave band lambda b , and another group of second filters and photoelectric detectors are used for detecting the light of fluorescent out wave band lambda c .

[0014] Further, the signal collecting unit comprises a rotating disc filter and a photoelectric detector, the signal exit of the second optical fiber faces the rotating disc filter, the rotating disc filter faces the photoelectric detector, the rotating disc filter respectively makes the light of fluorescent wave band lambda b and fluorescent out wave band lambda c pass, and the photoelectric detector simultaneously detects the light of fluorescent wave band lambda b and fluorescent out wave band lambda c .

[0015] Further, the fluorescence detection device for the tissue insensitive to ambient light further comprises a control display unit, the control display unit is connected with the data processing unit, and the control display unit controls the switching of the light source and the collection and display of the signal.

[0016] Still further, the control display unit is a touch screen.

[0017] The present application has the following advantages:

[0018] (1) The present application firstly measures under ambient light and background light, obtains the characteristics of ambient light (spectra H b and H c ), and measures the light signals (spectra S b and S c ) outside the fluorescent wave band and the fluorescent wave band range under the excitation light source, then obtains the correction coefficient based on the measurement results, obtains the ambient correction signal by using the correction coefficient, corrects the fluorescent signal by considering the ambient correction signal to obtain the fluorescent correction signal, finally judges whether it is the target tissue, the whole detection process is simple, considers eliminating the interference of natural light, ambient light and the like, avoids the correction error caused by the change of ambient light, is helpful to realize the in-vivo fluorescence detection insensitive to ambient light, and improves the stability and accuracy of in-vivo fluorescence detection.

[0019] (2) In ambient light correction, the conventional method is to subtract the spectrum collected when the excitation light is off from the fluorescence spectrum collected under excitation light illumination. However, under excitation light illumination, slight changes in detector angle or ambient light intensity can cause ambient light correction errors. This is especially true for handheld in-vivo detection devices, where even slight shaking can affect the intensity of ambient light entering the detector, leading to measurement results that are too high or too low. The correction method of this invention divides ambient light into fluorescence bands λ. b and fluorescence outer band λ c The spectral correction coefficients were obtained using fluorescence outer band spectroscopy. Since ambient light within the fluorescence band range changes synchronously with ambient light outside the fluorescence band range, the spectral correction coefficients obtained using fluorescence outer band spectroscopy can be used for fluorescence band λ under excitation light irradiation. b Ambient light correction is used to avoid background correction errors caused by changes in ambient light. Furthermore, this correction method is simple and requires no additional detection devices. Attached Figure Description

[0020] Figure 1 This is a block diagram of a fluorescence detection device for tissues that are not sensitive to ambient light, as provided in Embodiment 1 of the present invention.

[0021] Figure 2 This is a schematic diagram of a fluorescence detection device for tissues that are not sensitive to ambient light, as disclosed in Embodiment 1 of the present invention.

[0022] Figure 3 This is a flowchart of the operation of a fluorescence detection device for tissues that are not sensitive to ambient light, as disclosed in Embodiment 1 of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] like Figure 1 As shown, a fluorescence detection device for tissues insensitive to ambient light determines whether the tissue to be tested 6 is the target tissue by the intensity of the final detected fluorescence signal. The device includes an excitation light unit 1, a signal acquisition unit 2, a data processing unit 3, a control and display unit 4, and a probe 5.

[0026] like Figure 2As shown, the excitation light unit 1 comprises a light source 11 and a first filter 12, the light source 11 is opposite to the first filter 12, the light source 11 emits light with a spectral range of λ a which is converged into the first optical fiber 7 after passing through the first filter 12. In this embodiment, the measured spectral range is mainly divided into three parts, which are the excitation light band, the fluorescence band and the out-of-fluorescence band. The excitation light band λ a represents the excitation light spectral wavelength range; the fluorescence band λ b represents the fluorescence emission spectral wavelength range; and the out-of-fluorescence band λ c represents the part of the ambient light spectrum which does not include the excitation light spectral wavelength range λ a and the fluorescence emission spectral wavelength range λ b .

[0027] Continuing to refer to Figure 2 , the probe 5 is mainly used for transmission of excitation light and collection of signal light, and the main function of the probe 5 is to directly locate the tissue for smaller tissues, thereby providing convenience for the operator. The probe 5 is aligned with the measured tissue 6, the probe 5 is connected with the first optical fiber 7, and the probe 5 is connected with the signal acquisition unit 2 through the second optical fiber 8.

[0028] Continuing to refer to Figure 2 , the signal acquisition unit 2 comprises a second filter 21 and a photodetector 22, the signal exit of the second optical fiber 8 is opposite to the second filter 21, and the second filter 21 is opposite to the photodetector 22, and the photodetector 22 simultaneously receives the light with the fluorescence band λ b and the out-of-fluorescence band λ c returned by the measured tissue 6. In this embodiment, the second filter 21 is a notch filter which can filter out the light with the excitation light band λ a and simultaneously transmit the light with the spectral range in the fluorescence band λ b and the out-of-fluorescence band λ c . By using the notch filter, the ambient light outside the fluorescence band can pass through, while in the conventional fluorescence detection, a high-pass filter is used for filtering, and only the light in the fluorescence band can enter the detector. In this embodiment, the photodetector 22 is a spectrometer.

[0029] The data processing unit 3 collects the ambient light and the background light under the condition that the excitation light unit 1 is closed, obtains the spectra H b and H c corresponding to the fluorescence band λ b and the out-of-fluorescence band λ c , and obtains the spectra S b and S c corresponding to the fluorescence band λ b and the out-of-fluorescence band λ cS c / H c Obtain the correction coefficient α according to formula H x =H b ×α is used to obtain the environmental correction signal, according to the formula S = S b -H x =S b -H b ×α is used to obtain the fluorescence correction signal. When S≥β, it is determined to be the target tissue; when S<β, it is determined not to be the target tissue, where β is a reference value.

[0030] The control and display unit 4 is connected to the data processing unit 3, and controls the switching on and off of the light source 11, as well as the acquisition and display of signals. In this embodiment, the control and display unit 4 is a touch screen.

[0031] like Figure 3 As shown, the main process of tissue detection is as follows:

[0032] Step 1: Information Entry

[0033] When performing organizational identification, personal information is first entered into data processing unit 3, including: name, gender, age, height, weight, medical history, etc.

[0034] Step 2: Ambient Light Feature Acquisition

[0035] Data processing unit 3, with excitation unit 1 turned off, collects ambient light and background light, i.e., ambient light and background light serve as light source 11. Light source 11 is incident on the tissue to be tested 6, and the tissue to be tested 6 returns to the fluorescence band λ. b and fluorescence outer band λ c The light is transmitted through the second optical fiber 8 to the second filter 21, and then incident on the photodetector 22 to obtain the fluorescence band λ. b and fluorescence outer band λ c The corresponding spectrum H b and H c For the same environmental conditions, when measuring the same organization multiple times or multiple organizations, ambient light measurement only needs to be performed once.

[0036] Step 3: Organization Identification

[0037] With excitation unit 1 turned on, the emission excitation light spectrum range is λ. a The light is directed to the tissue under test 6, and the tissue under test 6 returns fluorescence in the λ band. b and fluorescence outer band λ c The light is transmitted through the second optical fiber 8 to the second filter 21, and then incident on the photodetector 22, thereby obtaining the fluorescence band λ under the condition of opening the excitation light unit 1. b and fluorescence outer band λ ccorresponding spectrum S b and S c .

[0038] Step 4: signal analysis processing

[0039] The spectrum signal H c and S c and is subjected to generalized linear fitting, or directly S c / H c The correction coefficient α is obtained, and the environmental correction signal is obtained according to the formula H x =H b ×α, the fluorescence correction signal is obtained according to the formula S=S b -H x =S b -H b ×α.

[0040] Step 5: tissue determination

[0041] The fluorescence correction signal S is compared with the reference value β, when S≥β, it is determined that it is the target tissue; when S<β, it is determined that it is not the target tissue.

[0042] Step 6: result display and record

[0043] The display unit 4 is controlled to display and store the result.

[0044] Through the above technical scheme, the present application firstly measures under the ambient light and the background light, obtains the ambient light characteristics (spectrum H b and H c ), and measures the light signal (spectrum S b and S c ) outside the fluorescence wave band and the fluorescence wave band range under the excitation light source 11, then obtains the correction coefficient based on the measurement results twice, obtains the environmental correction signal by using the correction coefficient, considers the environmental correction signal to correct the fluorescence signal to obtain the fluorescence correction signal, finally determines whether it is the target tissue, the whole detection process is simple, considers to eliminate the natural light, the ambient light and other interference, avoids the correction error caused by the change of the ambient light, is helpful to realize the in-vivo fluorescence detection which is not sensitive to the ambient light, improves the stability and the accuracy of the in-vivo fluorescence detection. The present application can not only be used for tissue fluorescence detection, but also can be used for other fluorescence detection which needs to correct the ambient light.

[0045] Example 2

[0046] The difference between the embodiment 2 and the embodiment 1 of the present application is the specific structure of the signal acquisition unit 2, the signal acquisition unit 2 in the embodiment 2 comprises two second filters 21 and two photoelectric detectors 22, the signal exit of the second optical fiber 8 has two, respectively facing two second filters 21, two second filters 21 respectively facing one photoelectric detector 22, one group of second filters 21 and photoelectric detectors 22 are used for detecting the light of the fluorescent wave band λ b , and the other group of second filters 21 and photoelectric detectors 22 are used for detecting the light of the fluorescent outer wave band λ c .

[0047] Embodiment 3

[0048] The difference between the embodiment 3 and the embodiment 1 of the present application is the specific structure of the signal acquisition unit 2, the signal acquisition unit 2 in the embodiment 3 comprises a rotating disc filter and a photoelectric detector 22, the signal exit of the second optical fiber 8 faces the rotating disc filter, the rotating disc filter faces the photoelectric detector 22, the rotating disc filter respectively makes the light of the fluorescent wave band λ b and the light of the fluorescent outer wave band λ c pass through, and the photoelectric detector 22 simultaneously detects the light of the fluorescent wave band λ b and the light of the fluorescent outer wave band λ c .

[0049] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit the same; although the present application is described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by the equivalent ones; and the modification or replacement does not make the essence of the corresponding technical solution deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A fluorescence detection apparatus for tissue that is insensitive to ambient light, characterized by, The device comprises an excitation light unit, a signal collecting unit and a data processing unit, the excitation light unit emits light with a spectral range of λ a to the tissue to be measured; the signal collecting unit receives the light with a spectral range of λ b and a spectral range of λ c returned by the tissue to be measured, and filters out the light with a spectral range of λ a ; the data processing unit collects ambient light and background light when the excitation light unit is off, obtains the corresponding spectra H b and H c of the spectral range of λ b and the spectral range of λ c , obtains the corresponding spectra S b and S c of the spectral range of λ b and the spectral range of λ c when the excitation light unit is on, obtains a correction coefficient α from S c / H c , obtains an ambient correction signal from the formula H x = H b × α, obtains a fluorescence correction signal from the formula S = S b -H x = S b -H b × α, and makes a result determination according to the corrected fluorescence signal. The signal collecting unit comprises a photoelectric detector and a second filter, the signal exit of the second optical fiber is directly opposite to the second filter, the second filter is directly opposite to the photoelectric detector, and the photoelectric detector simultaneously receives the fluorescent wave band λ b and the fluorescent outer wave band λ c of the returned light of the measured tissue; and the second filter is a notch filter.

2. A fluorescence detection apparatus for tissue that is insensitive to ambient light according to claim 1, wherein, The excitation light unit comprises a light source and a first filter, the light source is opposite to the first filter, the light source emits light with a spectral range of λ a which is converged into the first optical fiber after passing through the first filter.

3. A fluorescence detection apparatus for tissue that is insensitive to ambient light according to claim 2, wherein, The probe is arranged to aim at the tissue to be measured, and is connected with the first optical fiber and connected with the signal collecting unit through the second optical fiber.

4. The apparatus of claim 1, wherein the apparatus is configured to operate in a manner that is substantially insensitive to ambient light. The photoelectric detector is a spectrometer.

5. A fluorescence detection apparatus for tissue that is insensitive to ambient light according to claim 3, wherein The signal collecting unit comprises two second filters and two photoelectric detectors, the signal exit of the second optical fiber has two, respectively facing two second filters, two second filters respectively facing a photoelectric detector, wherein one set of second filters and photoelectric detectors are used for detecting light of fluorescent wave band λ b , and the other set of second filters and photoelectric detectors are used for detecting light of fluorescent outer wave band λ c .

6. A fluorescence detection apparatus for tissue that is insensitive to ambient light according to claim 3, wherein, The signal collecting unit comprises a rotating disc filter and a photoelectric detector, the signal exit of the second optical fiber is opposite to the rotating disc filter, the rotating disc filter is opposite to the photoelectric detector, the rotating disc filter allows the light of the fluorescent wave band λ b and the fluorescent out wave band λ c to pass through respectively, and the photoelectric detector detects the light of the fluorescent wave band λ b and the fluorescent out wave band λ c at the same time.

7. The fluorescence detection apparatus for tissue that is insensitive to ambient light according to claim 1, wherein The control display unit is connected with the data processing unit, and controls the switching of the light source and the collection of signals and the display of results.

8. A fluorescence detection apparatus for tissue that is insensitive to ambient light according to claim 7, wherein, The control display unit is a touch screen.

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