WO2019119576A1

WO2019119576A1 - Multi-mode imaging system

Info

Publication number: WO2019119576A1
Application number: PCT/CN2018/072608
Authority: WO
Inventors: 梁栋; 洪序达; 石伟; 龚小竞; 刘成波; 胡战利; 林日强; 郑海荣
Original assignee: 深圳先进技术研究院
Priority date: 2017-12-22
Filing date: 2018-01-15
Publication date: 2019-06-27
Also published as: CN108042110A

Abstract

A multi-mode imaging system, comprising a display (100), a multi-mode imaging device (200), and a host (300) electrically connected between the display (100) and the multi-mode imaging device (200). The host (300) is internally provided with an image reconstruction and processing subsystem. The multi-mode imaging device (200) is internally provided with an animal scanning control subsystem (201), a static computed tomography subsystem (220), and a photoacoustic imaging subsystem (230). The static computed tomography subsystem (220) comprises an electronic control circuit (221), a multi-beam carbon nano X-ray source array (222) used for generating X-rays (500) required by static computed tomography scanning, a photon counting detector (223) used for computed tomography projection data collection and high-speed processing, and a power supply (224) used for supplying power to the multi-beam carbon nano X-ray source array (222). The multi-beam carbon nano X-ray source array (222), the photon counting detector (223), and the power supply (224) are electrically connected to the electronic control circuit (221). The multi-mode imaging system is high in image resolution, large in imaging depth and low in radiation dosage.

Description

Multimode imaging system

Technical field

The present invention relates to the field of medical imaging technology, and more particularly to a multimode imaging system.

Background technique

Cancer is the most common type of malignancy, and it is the number one killer of human health. At present, global cancer cases are showing rapid growth, and new cases are mainly from developing countries. Due to its high mortality rate, high disability rate and medical burden, malignant tumors have become a public health issue and a social issue that must be highly valued all over the world. Among the lethal factors caused by cancer, tumor metastasis is the most important factor.

At present, the research on tumor metastasis is mainly carried out in small animals represented by mice and rats. In the specific study, the tumor disease model was first established in small animals, then the physiological-pathological characteristics of tumor metastasis, new cancer diagnosis techniques, anti-tumor drugs and evaluation of the efficacy of the drugs were studied. In various methods for studying small animals, small animal whole body imaging technology can perform whole-body and long-term observations of the same batch of small animals at different time points, greatly reduce the experimental cost, and obtain repetitive and reliable experimental data, while relying on high sensitivity. The molecular probe can be effectively observed in the early stage of tumor metastasis, thereby realizing the whole process of monitoring the whole process of tumor cells. The main imaging techniques involved include computed tomography (Computed) Tomography, CT), Magnetic Resonance Imaging (Magnetic Structural imaging such as Resonance Imaging, MRI) and Ultrasound, and photoacoustic imaging Imaging), Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (Single Photon) Functional imaging such as Emission Computed Tomography, SPECT). However, the information obtained by these single-modal imaging techniques has certain limitations and cannot fully reflect the complex specificity of the organism, leading to the failure to provide comprehensive and accurate information for the study of tumor metastasis.

In view of the above-mentioned shortcomings of single-modal imaging technology, the prior art proposes multi-modal imaging technology combining structural and functional information, and multi-modal imaging technology is increasingly being applied to small-body living body imaging, for example, Multimodal imaging technology combining PET and CT has become a clinical reference standard for multimodal molecular imaging, which has demonstrated value in predicting the efficacy of neoadjuvant therapy and new targeted therapy, and has recently been used to detect early tumor metastasis. For example, multimodal imaging techniques using optical imaging combined with PET have been used to detect lymphangiogenesis induced during tumor metastasis.

However, in the prior art, small animal whole body multi-mode imaging technology still has certain deficiencies. For example, in PET-CT imaging, the high-energy photon attenuation coefficient map obtained from CT images can improve the accuracy and resolution of PET; however, near-infrared photons are more susceptible to high-energy photons than PET or SPECT. The effect of tissue light absorption coefficient is used, so better attenuation can be obtained by using the attenuation correction concept in optical imaging. In addition, in the treatment of cancer, because the spatial resolution of PET/SPECT is too low, it is difficult to accurately describe the targeting and aggregation of drugs. In order to simultaneously obtain the overall and local drug metabolism, a pair that can respond to optical modes is often used. The model probe performs drug evaluation and analysis. However, due to the strong scattering effect of organisms, optical imaging technology often results in an imaging depth of only about 1 mm, which limits application. In addition, in modalities that provide high-resolution structural imaging, CT imaging has advantages in displaying anatomy, morphology, and density, and imaging speed is fast, and can also be performed by injecting contrast agents, using energy spectrum imaging, or phase contrast imaging. Enhance soft tissue contrast, but excessive X-ray radiation can alter the physiological structure of small animals and affect the correct judgment of the process of cancer development and the role of drugs. In the long-term longitudinal study of small animals using in vivo imaging techniques, it is also necessary to ensure that the small animal receives the radiation dose as low as possible to reduce its physiological impact on small animals. It can be seen that the existing small animal living body multi-mode imaging technology still has the problems of low image resolution, small imaging depth and large radiation dose in specific applications.

technical problem

The object of the present invention is to provide a multi-mode imaging system, which aims to solve the technical problem that the existing small animal living body multi-mode imaging technology has low image resolution, small imaging depth and large radiation dose in specific applications.

Technical solution

In order to achieve the above object, the present invention provides a multi-mode imaging system including a display, a multi-mode imaging device, and a host electrically connected between the display and the multi-mode imaging device. An image reconstruction and processing subsystem, the multi-mode imaging device having an animal scan control subsystem, a static computed tomography subsystem, and a photoacoustic imaging subsystem, the static computed tomography subsystem including an electronic control circuit for generating A multi-beam carbon nano-X source array of X-rays required for static computed tomography scanning, a photon counting detector for computed tomography projection data acquisition and high-speed processing, and a power supply for powering the multi-beam carbon nano-X source array The power source, the multi-beam carbon nano X-ray source array, the photon counting detector, and the power supply are all electrically connected to the electronic control circuit.

Optionally, the multi-beam carbon nano X-ray source array comprises a plurality of array-distributed carbon nano X-ray sources, including a vacuum cavity, a carbon nano-field emission cathode, a gate, a focusing electrode, and an anode. The carbon nano field emission cathode, the gate electrode, the focusing electrode and the anode are all disposed in the vacuum chamber, and the anode is obliquely disposed above the carbon nano field emission cathode, the gate And the focusing electrode is disposed between the carbon nano field emission cathode and the anode, and the gate is located between the focusing electrode and the carbon nano field emission cathode, and the vacuum chamber is provided An X-ray exit window located on the side of the anode.

Optionally, the carbon nanofield emission cathode comprises a substrate and a layer of cold cathode material disposed on the surface of the substrate.

Optionally, the substrate is a metal substrate or a silicon wafer coated with a metal coating; and/or,

The material of the cold cathode material layer is carbon nanotubes or graphene and a mixture of carbon nanotubes and graphene.

Optionally, the number of the carbon nano X light sources is 90-180; and/or,

Each of the carbon nano X light sources is distributed in a circular array or a polygonal array; and/or

The X-ray exit window is an aluminum window or a window; and/or,

The vacuum chamber has a vacuum of 10 ^-6 mmHg to 10 ^-11 mm Hg; and/or

The gate includes a bracket and a grid disposed on the bracket, the grid having an opening for electron transmission; and/or

The anode is formed at an angle of inclination of 5° to 15° with respect to a horizontal plane; and/or

The relative distance between the carbon nanofield emission cathode, the gate, the focusing electrode, and the anode is adjusted by an insulating spacer.

Optionally, the photoacoustic imaging subsystem includes an optical sub-system for providing excitation light required for photoacoustic imaging, an acoustic sub-system for acquiring multi-channel photoacoustic signals, and for adjusting the incident of the excitation light. An optical acoustic coplanar adjustment subsystem that maintains a coplanar optical signal and acoustic signal.

Optionally, the optical subsystem includes an excitation light source, a lens group, a fiber bundle, and an annular light bowl, the lens group being disposed between the excitation light source and the fiber bundle, the fiber bundle being fixed to the The annular light bowl is located between the lens group and the annular light bowl.

Optionally, the acoustic subsystem includes a high frequency ultrasound transducer array for detecting acoustic signals and a multi-channel data acquisition platform for processing the detection signals of the high frequency ultrasound transducer array.

Optionally, the high-frequency ultrasonic transducer array comprises a plurality of array-distributed high-frequency ultrasonic transducers, the high-frequency ultrasonic transducers being a multi-layer laminated structure including a stack of layers arranged in order from front to back Acoustic lens, matching layer, piezoelectric composite layer, insulating backing layer.

Optionally, the animal scan control subsystem includes a positioning structure for positioning the animal and an electromechanical control platform for driving the positioning structure and the animal on the positioning structure to move in a vertical direction; /or,

The image reconstruction and processing subsystem includes an image reconstruction module carrying an image reconstruction algorithm, an image calibration module carrying image correction and registration software, an image fusion module carrying multimodal image fusion software, and carrying Information output module for information extraction and display software.

Beneficial effect

The multi-mode imaging system provided by the invention adopts a multi-mode imaging technology formed by a combination of a static CT imaging subsystem and a photoacoustic imaging subsystem, and realizes synchronous acquisition of small animal structure and function information, and is compared with the existing multi-mode. The imaging system has the advantages of high image resolution, fast imaging speed, large imaging depth, low radiation dose, and long-term monitoring. Specifically, the present invention has the following advantageous effects as compared with the prior art:

(1) Static CT imaging subsystem using multi-beam carbon nano-X source array, without mechanical rotation, high-speed CT scanning can be realized by fast switching between individual carbon nano X-ray sources; and static CT imaging subsystem overcomes The limitation of mechanical speed, higher imaging speed, and elimination of artifacts caused by motion, resulting in higher spatial resolution. In addition, since the multi-beam carbon nano-X source array can perform high-speed pulse emission, the ineffective radiation dose during the CT scanning process is greatly reduced, thereby achieving the effect of ultra-low radiation.

(2) Unlike optical imaging technology, the spatial resolution of photoacoustic imaging sub-technology comes from ultrasonic signals, and the ultrasonic scattering of biological tissue is two orders of magnitude weaker than light scattering. Therefore, the present invention uses photoacoustic imaging technology to have both High optical contrast and the ability of ultrasound to image high resolution in deep tissue, coupled with molecular probes, can also have the advantages of high sensitivity, no radioactivity, and high specificity.

(3) The combination of static CT imaging technology and photoacoustic imaging technology has the characteristics of complementary, mutual cooperation and mutual control. On the one hand, it is easy to carry out 3D visualization to locate by means of the advantages of high resolution and ultra-low radiation of static CT imaging. Tumor tissue, on the other hand, can make accurate early diagnosis of tumor metastasis and accurate description of drug metabolism by utilizing the advantages of soft tissue contrast and high sensitivity of photoacoustic imaging.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and those skilled in the art can obtain other drawings according to the structures shown in the drawings without any creative work.

1 is a schematic structural diagram of a multimode imaging system according to an embodiment of the present invention;

2 is a schematic structural view of a carbon nano X light source according to an embodiment of the present invention.

Embodiments of the invention

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

It should be noted that all directional indications (such as up, down, left, right, front, back, ...) in the embodiments of the present invention are only used to explain between components in a certain posture (as shown in the drawing). Relative positional relationship, motion situation, etc., if the specific posture changes, the directional indication also changes accordingly.

It should also be noted that when an element is referred to as being "fixed on" or "in" another element, it can be directly on the other element or the central element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or a central element may be present.

In addition, the descriptions of "first", "second", and the like in the present invention are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include at least one of the features, either explicitly or implicitly. In addition, the technical solutions between the various embodiments may be combined with each other, but must be based on the realization of those skilled in the art, and when the combination of the technical solutions is contradictory or impossible to implement, it should be considered that the combination of the technical solutions does not exist. It is also within the scope of protection required by the present invention.

As shown in FIG. 1 and FIG. 2, the multi-mode imaging system provided by the embodiment of the present invention includes a display 100, a multi-mode imaging device 200, and a host 300 electrically connected between the display 100 and the multi-mode imaging device 200, and the host 300 An image reconstruction and processing subsystem (not shown) is provided therein. The multi-mode imaging device 200 is provided with an animal scanning control subsystem 210, a static computed tomography imaging subsystem 220 (ie, a static CT imaging subsystem), and a photoacoustic imaging subsystem. 230. The static computed tomography subsystem 220 includes an electronic control circuit 221, a multi-beam carbon nano-X-ray array 222 for generating X-rays 500 required for static computed tomography scanning, and a data acquisition and high-speed processing for computed tomography projection data. The photon counting detector 223 and the power supply 224 for powering the multi-beam carbon nano X-ray array 222, the multi-beam carbon nano X-ray array 222, the photon counting detector 223 and the power supply 224 are all electrically connected to the electronic control circuit 221 . The multi-mode imaging device 200 is mainly used for scanning imaging of the animal 400. The host computer 300 is mainly used for processing information of the multi-mode imaging device 200. The display 100 is mainly used for visually outputting the processed information of the host 300. In the multi-mode imaging device 200, the animal scan control subsystem 210 is mainly used to carry the animal 400 and carry the animal 400 for movement. The static computed tomography imaging subsystem 220 is mainly used for structural imaging of the animal 400, and photoacoustic imaging. System 230 is primarily used to functionally image animal 400,

Specifically, in the embodiment of the present invention, the static CT imaging subsystem adopting the multi-beam carbon nano X-ray source array 222 can realize high-speed CT scanning by performing fast switching between the respective carbon nano X-ray sources 2220 without mechanical rotation. And the static CT system overcomes the limitation of mechanical speed, has higher imaging speed, and eliminates artifacts caused by motion, thereby achieving higher spatial resolution. In addition, since the multi-beam carbon nano-X source array 222 can perform high-speed pulse emission, the ineffective radiation dose during the CT scanning process is greatly reduced, thereby achieving the effect of ultra-low radiation.

In addition, since the spatial resolution of the photoacoustic imaging sub-technology comes from the ultrasonic signal, and the ultrasonic scattering of the biological tissue is two orders of magnitude weaker than the light scattering, the embodiment of the present invention uses the photoacoustic imaging technology to have high optical contrast. It also has the ability to perform high-resolution imaging of ultrasound on deep tissue, and the addition of molecular probes can also have the advantages of high sensitivity, no radioactivity, and high specificity.

Since the imaging time of the two imaging subsystems of photoacoustic and static CT is different, when the system is working, the trigger signal of the photoacoustic subsystem can be precisely controlled by the clock of the static computed tomography subsystem 220 to The acquisition timing of the static computed tomography subsystem 220 is synchronized, so that simultaneous imaging of the two can be achieved.

The multi-mode imaging system provided by the embodiment of the invention adopts the scheme of combining the static CT imaging technology and the photoacoustic imaging technology, and has the advantages of complementary advantages, mutual cooperation, and mutual control. Among them, the static CT imaging has high resolution on the one hand. The advantages of ultra-low radiation make it easy to perform three-dimensional visualization to locate tumor tissue. On the other hand, using the excellent soft tissue contrast and high sensitivity of photoacoustic imaging, accurate early diagnosis of tumor metastasis and accurate description of drug metabolism can be achieved. Therefore, the multi-mode imaging system provided by the embodiment of the present invention adopts the multi-mode imaging technology formed by the combination of the static computed tomography imaging subsystem 220 and the photoacoustic imaging subsystem 230, thereby achieving simultaneous acquisition of the structure and function information of the animal 400. It has the advantages of high image resolution, fast imaging speed, large imaging depth, low radiation dose and long-term monitoring.

Preferably, the multi-beam carbon nano X-ray source array 222 includes a plurality of array-distributed carbon nano-X light sources 2220 including a vacuum chamber 2221, a carbon nano-field emission cathode 2222, a gate 2223, a focusing electrode 2224, and an anode. 2225, the carbon nano field emission cathode 2222, the gate 2223, the focusing electrode 2224 and the anode 2225 are all disposed in the vacuum chamber 2221, and the anode 2225 is obliquely disposed above the carbon nano field emission cathode 2222, and the gate 2223 and the focusing electrode 2224 Both are disposed between the carbon nano-field emission cathode 2222 and the anode 2225, and the gate 2223 is located between the focusing electrode 2224 and the carbon nano-field emitting cathode 2222. The vacuum chamber 2221 is provided with an X-ray exit window 2226 located beside the anode 2225. . Wherein, the multi-beam carbon nano X-ray array 222 is used to generate X-rays 500 of different projection angles required for static CT scanning, the photon counting detector 223 is used for collecting and high-speed processing of CT projection data, and the power supply 224 is used for giving more The beam carbon nano X-ray source array 222 is powered. The carbon nano X-ray source 2220 has the characteristics of stable current, high high-voltage resistance, and small focal spot. Specifically, the carbon nano X-ray source 2220 has a tube current greater than 0.1 mA, a tube voltage greater than 50 kV, and a focal point less than 0.1 mm.

Preferably, each carbon nano X light source 2220 is distributed in a circular array or a polygonal array, and the number of carbon nano X light sources 2220 is 90-180, which is convenient for 360° full coverage of the scanning angle.

Preferably, the X-ray exit window 2226 is an aluminum window or a sash window.

Preferably, the vacuum chamber 2221 has a vacuum of 10 ^-6 mm Hg to 10 ^-11 mm Hg.

Preferably, the carbon nanofield emission cathode 2222 includes a substrate and a layer of cold cathode material disposed on the surface of the substrate. The cold cathode material layer can be prepared by electrophoretic deposition or chemical vapor deposition, and its shape and size can be precisely controlled by a photolithography process; in addition, the shape of the cold cathode material layer is preferably elliptical or rectangular to obtain uniform size in all directions. Focus.

Preferably, the substrate is a metal substrate or a silicon plate coated with a metal coating; the metal substrate may specifically be a stainless steel sheet or a copper sheet or a titanium sheet or a molybdenum sheet, etc., and the metal coating may specifically be a copper coating or a titanium coating. Or molybdenum coating or iron.

Preferably, the material of the cold cathode material layer is carbon nanotubes or graphene and a mixture of carbon nanotubes and graphene.

Preferably, the carbon nano-field emission cathode 2222 is placed on the base of the vacuum chamber 2221.

Preferably, the gate 2223 includes a bracket and a grid disposed on the bracket, the grid having an opening for electron transmission. The gate 2223 is primarily used to provide the electric field required to emit electrons in the layer of cold cathode material. The openings in the grid are primarily used to ensure that electrons can pass through the gate 2223 to the anode 2225. The grid includes, but is not limited to, a tungsten mesh or a molybdenum mesh.

Preferably, the anode 2225 forms an angle of inclination A with respect to the horizontal plane of 5 to 15 degrees. The anode 2225 is mainly used for acceleration of an electron beam to obtain high-energy electrons. The anode 2225 has a reflective target that is primarily used to reflect the X-rays 500 produced by electron bombardment. The reflective target may be a tungsten target or a molybdenum target or the like.

In particular, focus electrode 2224 is primarily used to focus the electron beam to achieve a desired size of focus. The focusing electrode 2224 is provided with a focusing hole, which may be a circular hole that is rotationally symmetrical, or an elliptical hole or a rectangular hole that is not rotationally symmetrical.

Preferably, the relative distance between the carbon nano-field emitting cathode 2222, the gate 2223, the focusing electrode 2224 and the anode 2225 is adjusted by an insulating spacer (not shown), which is advantageous for achieving an optimum focusing effect.

Preferably, the power supply 224 includes two medium and low voltage power supplies and one high voltage power supply. The medium and low voltage power supplies are respectively connected to the gate 2223 and the focusing pole 2224, and the voltage range is 2kV - 5kV; the high voltage power supply is connected to the anode 2225, and the power supply range is 50kV - 140kV.

Specifically, the photon counting detector 223 has the characteristics of high-speed data acquisition, high spatial resolution, and high-capacity resolving power, and can fully utilize the advantages of high-speed pulse exposure of the carbon nano X-ray source array 222. The photon counting detector 223 has a ring shape or a polygonal shape, and the X-ray conversion material may be cadmium telluride or cadmium zinc cadmium. The size of the photon counting detector 223 in the vertical direction is preferably greater than 0.5 cm, and the pixel is preferably less than 100 micrometers.

Preferably, the electronic control circuit 221 includes a pulse drive and timing control circuit, a current consistency control circuit, and a parallel exposure and data acquisition control circuit. The pulse driving and timing control circuit is used to realize the switching of the carbon nano X light source 2220 and the adjustment of the exposure time, and realize fast switching between different carbon nano X light sources 2220. Due to the limitation of the preparation process, the field emission performance of the cathode is inevitably different, and the current consistency control system can modulate the emission current of the cathode by precisely adjusting the voltage of the gate 2223 of each carbon nano X-ray source 2220, thereby making it possible to Different carbon nano X-ray sources 2220 maintain current consistency during operation, thereby ensuring the same exposure dose at different angles. The parallel exposure and data acquisition circuit triggers the opening of the carbon nano X-ray source 2220 mainly by the trigger signal when the detector is turned on, thereby realizing the synchronization of the carbon nano X-ray source 2220 exposure and the detector data acquisition.

Preferably, the pulse drive and timing control circuit includes a drive circuit, a control circuit, and an isolation protection circuit. The driving circuit is preferably a driving circuit based on an IGBT (Insulated Gate Bipolar Transistor), which is mainly used for realizing control of a weak electric signal (kV high voltage); the control circuit is preferably based on FPGA (Field-Programmable Gate Array (field programmable gate array) control circuit is mainly used to achieve high time precision programmable signal output; isolation circuit is mainly used to ensure effective protection of the control system.

Preferably, the current consistency control circuit includes a gate current adjustment unit, a gate current measurement unit, and a control element.

Specifically, the multimode imaging device 200 further includes a housing 240 in which the animal scan control subsystem 210, the static computed tomography subsystem 220, and the photoacoustic imaging subsystem 230 are all disposed.

Preferably, the photoacoustic imaging subsystem 230 includes an optical subsystem 231 for providing excitation light required for photoacoustic imaging, an acoustic subsystem 232 for acquiring multiplexed photoacoustic signals, and for adjusting the angle of incidence of the excitation light to A photoacoustic coplanar adjustment subsystem (not shown) that ensures that the optical signal is coplanar with the acoustic signal. The optical subsystem 231 is primarily used to provide excitation light required for photoacoustic imaging, including an excitation source and a multi-wavelength optical focusing component. The acoustic subsystem 232 is mainly used for collecting multi-channel photoacoustic signals, and is mainly composed of a high-frequency ultrasonic transducer array 2321 and a multi-channel data acquisition platform 2322. The photoacoustic coplanar adjustment subsystem is mainly used to automatically adjust the incident angle of the excitation light to ensure that the light/sound is always coplanar.

In a specific application, due to the non-uniformity of the outer circumference of the animal 400, during the overall scanning process of the animal 400, the coincidence of photoacoustic excitation (beam cut surface) and photoacoustic detection (sound beam cut surface) cannot always be maintained, thereby causing The decrease in signal-to-noise ratio greatly affects the quality of image reconstruction. In the embodiment, the photoacoustic coplanar adjustment subsystem monitors the accurate size of the outer circumference of the animal 400 by CT, calculates the exact position of the illumination incident surface, and controls the incident angle of the illumination so that it is always coplanar with the ultrasonic detection position, thereby ensuring High excitation-detection efficiency of photoacoustics.

Preferably, the optical subsystem 231 comprises an excitation light source, a lens group, a fiber bundle and an annular light bowl. The lens group is disposed between the excitation light source and the fiber bundle, and the fiber bundle is fixed on the annular light bowl and located in the lens group and the ring shape. Between the light bowls. The lens group, the fiber bundle, and the annular light bowl together form a multi-wavelength optical focusing component. Among them, the fiber bundle is mainly used for coupling transmission of excitation light; the annular light bowl is mainly used for fixing the fiber bundle.

Preferably, the excitation source is a high energy fast nanosecond pulsed optical parametric oscillator; the lens group comprises a beam splitter, a plano-convex lens, a collimating lens and a focusing lens.

Preferably, the acoustic subsystem 232 includes a high frequency ultrasound transducer array 2321 for detecting acoustic signals and a multi-channel data acquisition platform 2322 for processing the detection signals of the high frequency ultrasound transducer array 2321. The high frequency ultrasonic transducer array 2321 is mainly used for detecting the excited acoustic signal, which may specifically be a ring structure. The multi-channel data acquisition platform 2322 is mainly used for processing the detection signals. The multi-channel data acquisition platform 2322 can respectively perform separate data acquisition, amplification, filtering and other pre-processing channels for each array element of the high-frequency ultrasonic transducer array 2321, thereby realizing real-time high-speed data acquisition and pre-processing.

Preferably, the high frequency ultrasound transducer array 2321 includes a plurality of array distributed high frequency ultrasound transducers, each high frequency ultrasound transducer corresponding to one array element of the high frequency ultrasound transducer array 2321. The high-frequency ultrasonic transducer is a multi-layer laminated structure including an acoustic lens, a matching layer, a piezoelectric composite material layer, and an insulating backing layer which are laminated in this order from front to back.

Preferably, the animal scan control subsystem 210 includes a positioning structure 211 for positioning the animal 400 and an electromechanical control platform 212 for driving the positioning structure 211 and the animal 400 on the positioning structure 211 to move in a vertical direction. The positioning structure 211 is mainly used for accurately fixing the animal 400, and the electromechanical control platform 212 is mainly used for controlling the effect of moving the animal 400 in the vertical direction.

Preferably, the image reconstruction and processing subsystem comprises an image reconstruction module carrying an image reconstruction algorithm, an image calibration module carrying image correction and registration software, an image fusion module carrying multi-modal image fusion software, and a bearing There is an information output module for information extraction and display software. The image reconstruction module specifically carries a reconstruction algorithm of the CT image and the photoacoustic image.

Embodiments of the present invention provide an animal 400 whole body multi-mode imaging technique and system with high spatial resolution, large imaging depth, extremely low side effects, and long-term monitoring. Among them, the static computed tomography imaging subsystem 220 has the advantages of fast imaging speed, high spatial resolution, and ultra-low radiation dose, and the photoacoustic imaging subsystem 230 has the characteristics of large imaging depth, high sensitivity and specificity. And it has been demonstrated that the fusion of the static computed tomography subsystem 220 and the photoacoustic imaging subsystem 230 is feasible.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structural transformation, or direct/indirect use, of the present invention and the contents of the drawings are used in the inventive concept of the present invention. It is included in the scope of the patent protection of the present invention in other related technical fields.

Claims

A multi-mode imaging system, comprising: a display, a multi-mode imaging device, and a host electrically connected between the display and the multi-mode imaging device, wherein the host is provided with an image reconstruction and processing subsystem, The multi-mode imaging device is provided with an animal scanning control subsystem, a static computed tomography subsystem and a photoacoustic imaging subsystem. The static computed tomography subsystem includes an electronic control circuit for generating a static computed tomography scan. a multi-beam carbon nano X-ray source array of rays, a photon counting detector for computer tomographic projection data acquisition and high-speed processing, and a power supply for powering the multi-beam carbon nano X-ray array, the multi-beam carbon nano The X-ray source array, the photon counting detector, and the power supply are all electrically connected to the electronic control circuit.
The multimode imaging system of claim 1 wherein said multi-beam carbon nano X-ray source array comprises a plurality of array-distributed carbon nano X-ray sources, said carbon nano-X source comprising a vacuum chamber, a carbon nanofield a cathode, a gate, a focusing electrode, and an anode, wherein the carbon nano-field emitting cathode, the gate, the focusing electrode, and the anode are both disposed in the vacuum chamber, and the anode is obliquely disposed at the Above the carbon nanofield emission cathode, the gate and the focusing electrode are both disposed between the carbon nano field emission cathode and the anode, and the gate is located at the focusing pole and the carbon nanofield Between the emission cathodes, the vacuum chamber is provided with an X-ray exit window on the side of the anode.
The multimode imaging system of claim 2 wherein said carbon nanofield emission cathode comprises a substrate and a layer of cold cathode material disposed on said substrate surface.
The multimode imaging system of claim 3 wherein said substrate is a metal substrate or a silicon wafer coated with a metal coating; and/or,

The material of the cold cathode material layer is carbon nanotubes or graphene and a mixture of carbon nanotubes and graphene.
The multimode imaging system according to any one of claims 2 to 4, wherein the number of the carbon nano X light sources is 90-180; and/or

Each of the carbon nano X light sources is distributed in a circular array or a polygonal array; and/or

The X-ray exit window is an aluminum window or a window; and/or,

The vacuum chamber has a vacuum of 10 -6 mmHg to 10 -11 mm Hg; and/or

The gate includes a bracket and a grid disposed on the bracket, the grid having an opening for electron transmission; and/or

The anode is formed at an angle of inclination of 5° to 15° with respect to a horizontal plane; and/or

The relative distance between the carbon nanofield emission cathode, the gate, the focusing electrode, and the anode is adjusted by an insulating spacer.
A multimode imaging system according to claim 1 wherein said photoacoustic imaging subsystem includes an optical sub-system for providing excitation light required for photoacoustic imaging for acquisition of multiplexed photoacoustic signals. An acoustic subsystem and a photoacoustic coplanar adjustment subsystem for adjusting the angle of incidence of the excitation light to ensure that the optical signal remains coplanar with the acoustic signal.
The multimode imaging system of claim 6 wherein said optical subsystem comprises an excitation source, a lens group, a fiber bundle, and an annular light bowl, said lens assembly being disposed in said excitation source and said fiber Between the bundles, the bundle of fibers is secured to the annular light bowl and between the lens set and the annular light bowl.
A multimode imaging system according to claim 6 or claim 7 wherein said acoustic subsystem includes a high frequency ultrasound transducer array for detecting acoustic signals and for translating said high frequency ultrasound A multi-channel data acquisition platform for processing the detector signals of the array.
A multimode imaging system according to claim 8 wherein said array of high frequency ultrasound transducers comprises a plurality of arrays of high frequency ultrasound transducers, said high frequency ultrasound transducers being multi-layer laminates The structure includes an acoustic lens, a matching layer, a piezoelectric composite material layer, and an insulating backing layer which are laminated in this order from front to back.
A multimode imaging system according to any one of claims 1 to 4, wherein said animal scanning control subsystem comprises a positioning structure for positioning an animal and for driving said positioning structure An electromechanical control platform that moves in a vertical direction with the animal on the positioning structure; and/or,

The image reconstruction and processing subsystem includes an image reconstruction module carrying an image reconstruction algorithm, an image calibration module carrying image correction and registration software, an image fusion module carrying multimodal image fusion software, and carrying Information output module for information extraction and display software.