CN103389287B - A kind of high-resolution optics system being applicable to the surface imaging of live body liver - Google Patents

Abstract

The present invention relates to a kind of high-resolution optics system being applicable to the surface imaging of live body liver, comprise a Ti∶Sapphire laser locked mode femto-second laser, an acousto-optic modulator, an optical scanning device, a variable mirror, a microcobjective, an objective table, a dichroic beam splitter, a near infrared filter plate, a reflection grating, a photomultiplier tube array, a computing machine controlled processing unit, semiconductor laser instrument and an imageing sensor.The present invention is reasonable in design, is skillfully constructed, and has vast potential for future development and larger dissemination.

Description

A high-resolution optical system suitable for live liver surface imaging

technical field

The invention relates to a high-resolution optical system suitable for live liver surface imaging.

Background technique

As we all know, the liver surface is mainly composed of extracellular matrix (collagen fibers and elastic fibers), liver cells and microcirculation system. These components are of great significance to the structural support and function of the liver. When the liver is damaged or diseased, these components will also undergo corresponding changes, such as the proliferation of extracellular matrix, changes in the morphology and metabolism of liver cells, and changes in microvascular morphology and microvascular dynamics. In addition, since these changes all occur at the micron scale. Therefore, it is of great value to realize the extraction and visualization of information such as these components and their structures at the micron scale for the study of liver physiology and the diagnosis of liver diseases.

However, current imaging techniques, such as conventional endoscopy, X-ray imaging, magnetic resonance imaging, computed tomography, ultrasound imaging, positron emission tomography, and optical coherence tomography, are The detection of these changes is not yet possible at the micron scale.

In recent years, multiphoton imaging technology has shown great potential in the application of in vivo high-resolution imaging because it can realize information integration and visualization of biological tissues at the micron scale. This technology utilizes nonlinear optical effects such as Second Harmonic Generation (SHG) and Two-Photon Excited Fluorescence (TPEF) generated by the interaction between the laser and the internal components of the tissue. High-resolution imaging of reduced nicotinamide adenine dinucleotide (NADH) and oxidized falvin adenine dinucleotide (FAD), extracellular matrix-derived collagen fibers and elastic fibers. At the same time, the fluorescence intensity ratio of two different TPEF signal bands (430-490 nm and 500-560 nm) of cell origin can be used as an endogenous indicator for evaluating cell metabolism. In addition, laser speckle imaging technology can perform real-time full-field imaging of microcirculatory blood flow in living organisms with high temporal and spatial resolution. Due to the advantages of non-contact, non-invasive, and fast imaging, laser speckle imaging technology is very suitable for the measurement of blood microcirculation. Microcirculation parameters such as blood vessel diameter, blood vessel density, blood flow velocity and blood perfusion can be measured using laser speckle technology. It can be speculated that laser speckle imaging technology also has great application potential in monitoring the microcirculation system on the surface of living liver.

Therefore, the development of a high-resolution optical system based on the combination of multiphoton imaging technology and laser speckle imaging technology can provide a new technology for the extraction and visualization of the main components and structures of the living liver surface at the micron scale. Physiological research and liver disease diagnosis are of great significance.

Contents of the invention

In view of this, the object of the present invention is to provide a high-resolution optical system suitable for imaging the surface of living liver.

The present invention is realized by the following scheme: a high-resolution optical system suitable for living liver surface imaging, including a Ti:Sapphire mode-locked femtosecond laser, characterized in that: the near-infrared super The short pulse light passes through an acoustic light modulator for power attenuation, then passes through a dichroic beam splitter, an optical scanning device and a variable mirror, and then passes through a microscope objective lens to reach the surface of the living liver on the stage to excite and generate endogenous A non-linear optical signal, the optical signal reaches a dichroic beam splitter through the microscopic objective lens, variable mirror and optical scanning device, and then the optical signal separated by a near-infrared filter enters a reflection grating , the reflective grating separates optical signals according to different wave bands and leads them to a photomultiplier tube array for detection, and inputs the detected signals into a computer control processing unit to realize imaging of endogenous nonlinear optical signals in different wave bands; then, A semiconductor laser is provided to be incident on the living liver surface on the stage to generate a scattered light signal, and the scattered light signal is guided to an image sensor for detection through the microscopic objective lens and variable mirror, and the detected The signal is input to the computer control processing unit to realize laser speckle blood flow imaging.

In an embodiment of the present invention, the semiconductor laser is incident on the stage at a horizontal angle of 30°.

In an embodiment of the present invention, the variable reflector can switch between reflective mirrors and empty mirrors.

In an embodiment of the present invention, the titanium sapphire mode-locked femtosecond laser is a high repetition rate ultrashort pulse laser with a frequency of 84 MHz, an ultrashort pulse of 10 fs, a wavelength range of 730-980 nm, and an output power of is 1.8W.

In an embodiment of the present invention, the reflective grating is a high-quality reflective grating, which acts as a light splitter and can separate optical signals into different wavelength bands with an interval of 6 nm.

In an embodiment of the present invention, the photomultiplier tube array is composed of 30 photomultiplier tubes, and the detected wavelength range is 380-560 nm.

In one embodiment of the present invention, the semiconductor laser is a miniature semiconductor laser with a wavelength of 650 nm and an output power of 30 mW.

The remarkable advantage of the present invention lies in: the high-resolution imaging of cell-derived NADH and FAD, and extracellular matrix-derived collagen fibers and elastic fibers by utilizing endogenous nonlinear optical signals generated by the interaction between the femtosecond laser and the internal components of the liver surface, Realize the extraction and visualization of change information such as the morphology and metabolism of liver cells, the structure and function of extracellular matrix; use the scattered light signal generated by the semiconductor laser incident on the liver surface to image the liver microcirculation system, so as to realize the imaging of the liver surface Monitoring and visualization of microvascular morphology and microblood flow dynamic information; the optical system based on the combination of multiphoton imaging technology and laser speckle imaging technology provides a new method and new technology for high-resolution imaging of the liver surface in vivo, and has great impact on the study of liver physiology. and liver disease diagnosis has great value. The invention is reasonable in design, ingenious in conception, has broad development prospects and great popularization significance.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below through specific embodiments and related drawings.

Description of drawings

Fig. 1 is a schematic diagram of the system structure of the present invention.

Detailed ways

The present invention utilizes the femtosecond laser to interact with the internal components of the liver surface to generate endogenous nonlinear optical signals for high-resolution imaging of cell-derived NADH and FAD, and extracellular matrix-derived collagen fibers and elastic fibers to realize the morphology of liver cells and metabolism, structure and function of extracellular matrix, etc., and then use the scattered light signal generated by the semiconductor laser incident on the liver surface to image the liver microcirculation system, so as to realize the microvascular morphology and microvascular morphology of the liver surface. Monitoring and visualization of hemodynamic information.

As shown in Fig. 1, the present invention provides a high-resolution optical system suitable for living liver surface imaging, including a Ti:Sapphire mode-locked femtosecond laser 1, and the near-infrared super The short pulse light passes through the acoustic light modulator 2 for power attenuation, then passes through a dichroic beam splitter 7, an optical scanning device 3 and a variable reflector 4, and then passes through a microscope objective lens 5 to reach the living liver on the stage 6 The surface is excited to generate an endogenous nonlinear optical signal, and the optical signal reaches a dichroic beam splitter 7 through the microscopic objective lens 5, the variable mirror 4 and the optical scanning device 3, and then passes through a near-infrared filter 8. The separated optical signal is incident on a reflective grating 9, and the reflective grating 9 separates the optical signal according to different wavelength bands and guides a photomultiplier tube array 10 for detection, and inputs the detected signal into a computer control processing unit 15, Realize the imaging of endogenous nonlinear optical signals in different wavelength bands (SHG: 390-410 nm, TPEF: 430-490 nm and TPEF: 500-560 nm), so as to realize the NADH and FAD of cell origin and the source of extracellular matrix High-resolution imaging of collagen fibers and elastic fibers, through image analysis can extract information such as hepatic cell morphology and metabolism, collagen fibers and elastic fibers fine structure; then, provide a semiconductor laser 12 incident on the living body on the stage 6 The surface of the liver generates a scattered light signal, the scattered light signal is directed to an image sensor 13 (CCD) for detection through the microscope objective lens 5 and variable mirror 4, and the detected signal is input to the computer for control and processing The unit realizes laser speckle blood flow imaging14, and can extract microcirculation information such as blood vessel diameter, blood vessel density, blood flow velocity and blood perfusion through image analysis.

Preferably, the semiconductor laser is incident on the stage at a horizontal 30°; the titanium sapphire mode-locked femtosecond laser is a high repetition rate ultrashort pulse laser with a frequency of 84 MHz and an ultrashort pulse of 10 fs, the wavelength range is 730-980 nm, and the output power is 1.8 W; the reflective grating is a high-quality reflective grating, which acts as a light splitter, and can separate optical signals into different wave bands with an interval of 6 nm; the photoelectric The multiplier tube array is composed of 30 photomultiplier tubes, and the detection wavelength range is 380-560 nm; the semiconductor laser is a miniature semiconductor laser with a wavelength of 650 nm and an output power of 30 mW.

It is worth mentioning that the variable reflector is a mirror with a switch effect, which can reflect or transmit light, and can realize reflective mirrors and empty mirrors (that is, transmissive mirrors, and light can directly pass through empty mirrors). ) switching, when the near-infrared ultrashort pulse light emitted by the Ti:Sapphire mode-locked femtosecond laser passes through the optical scanning device, the variable mirror is switched to a reflector to facilitate the incident near-infrared ultrashort pulse light into the microscope objective lens. After the scattered light signal passes through the microscope objective lens, the variable mirror is switched to an empty mirror so that the scattered light signal is incident on the image sensor.

The above-listed preferred embodiments have further described the purpose, technical solutions and advantages of the present invention in detail. It should be understood that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included within the protection scope of the present invention.

Claims (7)

1. one kind is applicable to the high-resolution optics system of live body liver surface imaging, comprise a Ti∶Sapphire laser locked mode femto-second laser, it is characterized in that: the near infrared ultrashort pulse light that described Ti∶Sapphire laser locked mode femto-second laser inspires carries out power attenuation through an acousto-optic modulator, again through a dichroic beam splitter, arrived the live body liver surface on objective table by a microcobjective after one optical scanning device and a variable mirror, excite and produce endogenous non-linearity luminous signs, described light signal is through described microcobjective, variable mirror and optical scanning device arrive a dichroic beam splitter, a reflection grating is incided again through the isolated light signal of a near infrared filter plate, light signal is separated by different-waveband described reflection grating and the photomultiplier tube array that leads detects, and the signal detected is inputted a computing machine controlled processing unit, realize the imaging of different-waveband endogenous non-linearity luminous signs, then, the live body liver providing semiconductor laser instrument to incide on described objective table is surperficial, produce a scattered light signal, described scattered light signal detects through described microcobjective and the variable mirror imageing sensor that leads, and the signal detected is inputted described computing machine controlled processing unit, realize laser speckle blood current imaging.

2. a kind of high-resolution optics system being applicable to the surface imaging of live body liver according to claim 1, is characterized in that: described semiconductor laser incides on described objective table with level 30 °.

3. a kind of high-resolution optics system being applicable to the surface imaging of live body liver according to claim 1, is characterized in that: described variable mirror can realize the switching of catoptron and empty mirror.

4. a kind of high-resolution optics system being applicable to the surface imaging of live body liver according to claim 1, it is characterized in that: described Ti∶Sapphire laser locked mode femto-second laser is the ultrashort pulse laser of high repetition frequency, frequency reaches 84 MHz, ultrashort pulse is 10 fs, wavelength coverage is 730-980 nm, and output power is 1.8 W.

5. a kind of high-resolution optics system being applicable to the surface imaging of live body liver according to claim 1, it is characterized in that: described reflection grating is a high-quality reflection grating, play a point light action, light signal can be separated by different-waveband, interval 6 nm.

6. a kind of high-resolution optics system being applicable to the surface imaging of live body liver according to claim 1, is characterized in that: described photomultiplier tube array is made up of 30 photomultipliers, the wavelength coverage 380-560 nm of detection.

7. a kind of high-resolution optics system being applicable to the surface imaging of live body liver according to claim 1, it is characterized in that: described semiconductor laser is mini semiconductor laser, wavelength 650nm, output power is 30 mW.