Human body peripheral blood vessel photoacoustic three-dimensional imaging device and imaging method thereof

Abstract

The invention discloses a human body peripheral blood vessel photoacoustic three-dimensional imaging device and an imaging method thereof, and belongs to the field of blood vessel imaging. Through high resolution and functional monitoring capability of photoacoustic imaging, detailed blood vessel structure and blood flow dynamic information are provided, and early recognition and treatment effect evaluation of common lesions such as diabetic foot and peripheral artery diseases are promoted; meanwhile, a mechanical system is adopted, so that the detection front end with relatively high quality can be borne, and stable operation is realized, and a relatively good photoacoustic imaging result is obtained; the system has a highly stable accurate scanning imaging mode, and is convenient for multiple imaging modes of clinical application; through the arrangement of the imaging water tank and the lifting structure of the imaging water tank, switching of imaging modes in a limited space can be ensured, so that the device can be suitable for the layout of a portal type three-dimensional moving device. The system is expected to promote the portability of equipment, reduce the research and development cost of the equipment, be widely applied to clinical practice and community medical treatment, and improve the disease management level.

Description

TECHNICAL FIELD

[0001] The present application relates to blood vessel imaging technology, in particular to a human peripheral blood vessel photoacoustic three-dimensional imaging device and an imaging method thereof. BACKGROUND

[0002] Peripheral small blood vessels (limbs, trunk and head and face, etc.) are closely related to many diseases (such as diabetic foot, peripheral arterial disease, etc.). Traditional imaging techniques such as ultrasound, CT and MRI have problems such as insufficient resolution, expensive equipment, radiation risk or toxicity or allergy of contrast agent in imaging of peripheral small blood vessels. As an emerging technology, photoacoustic imaging combines the advantages of high contrast of optical imaging and high penetration depth of ultrasonic imaging, and can provide non-invasive and non-radiation blood vessel morphological and functional information (such as blood oxygen saturation), which is particularly suitable for the imaging needs of peripheral blood vessels. This technology has wide application prospects in clinical practice, including early diagnosis, disease monitoring, surgical navigation and personalized treatment plan development. For example, in the early intervention of diabetic foot and peripheral arterial disease, photoacoustic imaging can help doctors detect lesions earlier and evaluate treatment effectiveness. Developing a dedicated photoacoustic imaging device for peripheral blood vessels can significantly improve the diagnosis level of blood vessel-related diseases, improve the quality of life of patients, and has important clinical significance and market value. The following needs are required in clinical practice: 1) Fast imaging speed: not only improves the compliance of the subject, but also significantly reduces the artifacts caused by involuntary motion of the subject during imaging; 2) Portable device: can be pushed to the bedside of a general ward for use, with a wider application scenario; 3) High device stability to ensure no vibration and stable speed during scanning.

[0003] 4) Ability to perform precise imaging of multiple sites, and ability to switch different scanning modes for different parts of the human body, and to perform precise imaging of target areas under guidance.

[0004] Fast imaging speed requires increasing the size of the probe, so that signals can be collected from a larger range and more angles at one time. The requirement of precise imaging of multiple sites requires the probe to be able to move in a large range and to perform high-precision scanning according to the outline of the target human imaging site. Therefore, there is an urgent need for a system that can stably support a large-size scanning probe and easily perform fast bedside imaging of multiple sites of the body.

[0005] Under the current technical background, there are some systems for photoacoustic imaging of peripheral blood vessels of the human body, and these systems have the following advantages and disadvantages: 1. Artificial handheld probe: the operator holds the photoacoustic probe on the body surface during imaging. The advantage is that the position of the probe can be set flexibly, and the adjustment space is large. The disadvantage is that it requires higher technical requirements for the operator, is easily disturbed by the operator's shaking, and the volume and weight of the probe cannot be too large. And for large-area imaging mode, it is difficult for manual to ensure the accuracy of imaging. At the same time, due to the operation difference of different operators, even the same operator's operation is not consistent before and after, which will lead to the difference of imaging effect, affecting the imaging quality and later analysis. CN113057581A, CN118806238A, CN105167747A.

[0006] 2. Stacked three-dimensional translation table: this design is to use XYZ three-dimensional scanning translation table through stacking. When used, the three-dimensional translation table is placed on one side of the object to be imaged, and the photoacoustic probe is connected to the stacked translation table through a cantilever structure extending from one side. The system is simple, but the design has the disadvantage that the center of gravity of the structure deviates during scanning and imaging, and the stability will decrease when the load is large and the imaging area is large. It is only suitable for driving a relatively small scanning head and cannot meet the demand for large-size scanning probes. Moreover, the stacking of one axis itself also occupies the scanning space, resulting in low space utilization of the design.

[0007] 3. Multi-axis mechanical arm driving: using a mechanical arm to replace a three-dimensional translation table to control the probe for scanning. The advantage is high scanning flexibility. However, if the mechanical arm is to achieve high three-dimensional scanning accuracy under large load and large scanning range, there are significant disadvantages such as high equipment and maintenance costs and complex operation. And due to the multi-axis flexibility of the mechanical arm, complex programming control is still needed to adapt to individual imaging needs, which requires high operation level of personnel. CN218651782U, CN118902383A.

[0008] 4. In some industrial loading and unloading devices, a portal structure is also used, but its main function is to place the crane on a movable crossbeam, so that large weight objects suspended by traditional load-bearing cables can be moved. Due to the use of flexible cables, it cannot be dynamically positioned in real time with high precision under fast motion, which does not meet the high precision requirement of the scanning process of the photoacoustic imaging probe. SUMMARY

[0009] In view of the problems existing in the prior art, the present application provides a human peripheral blood vessel photoacoustic three-dimensional imaging device and an imaging method thereof, which can work stably and portably, realize high-precision, high-resolution, non-invasive and non-radiation blood vessel imaging of the target area of human peripheral blood vessels, and make up for the deficiency of traditional imaging technology in peripheral small blood vessel imaging, so as to meet the demand of clinical early diagnosis and monitoring of blood vessel lesions.

[0010] One object of the present application is to provide a human peripheral blood vessel photoacoustic three-dimensional imaging device.

[0011] The three-dimensional moving device comprises an X-axis translation structure, a Y-axis translation structure and a Z-axis translation structure arranged on a base plate. The structure features a wide imaging operation space provided below the top beam in the two pillars for placing the first imaging tank and the second imaging tank. Different imaging tanks are replaced to adapt to the imaging requirements of different parts imaged in the imaging tank and under the imaging tank. The first imaging tank is fixed to the base plate of the three-dimensional moving device, the three-dimensional moving device is fixed in a light-shielded shell, the light-shielded shell is fixed on a lifting platform, and the imaging part is directly placed in the first imaging tank for imaging. The bottom of the second imaging tank is fixed on the imaging tank lifting device, and the imaging tank lifting device is fixed on the base plate of the three-dimensional moving device. The bottom of the second imaging tank is provided with a hole, and a light-transmitting and sound-transmitting flexible film is covered thereon. After coupling agent is added in the second imaging tank, the light-transmitting and sound-transmitting flexible film covers the imaging part, so that the path from the probe to the imaging part is free of air to complete the imaging. The imaging tank lifting device is fixed on both sides of the bottom of the second imaging tank and does not block the hole in the bottom of the second imaging tank and the imaging part. At this time, the imaging part is placed under the second imaging tank for imaging. The height of the second imaging tank is adjusted by the imaging tank lifting device to adapt to the imaging requirements of different imaging parts imaged under the second imaging tank. The two imaging tank forms can easily switch the imaging mode of the system between the imaging mode in the tank and the imaging mode under the tank, and the sufficient imaging space below the top beam of the three-dimensional moving device can be better utilized.

[0012] The human peripheral blood vessel photoacoustic three-dimensional imaging device comprises a three-dimensional moving device, a probe rotating device, a lifting platform, a probe, a signal processor, a data collector, an imaging tank, an imaging tank lifting device, a laser, an optical fiber bundle, an upper camera positioning device, a profile measuring device and a computing platform. The three-dimensional moving device is arranged on the lifting platform, and the imaging area is below the three-dimensional moving device, i.e. below the top beam in the two pillars. The probe is installed on the probe rotating device, and the probe rotating device is installed on the translation structure of the three-dimensional moving device. The laser is connected to the light inlet of the optical fiber bundle, and the light outlet of the optical fiber bundle is fixed at the front end of the probe. The probe is connected to the signal processor and collected by the data collector. The upper camera positioning device is located above the imaging tank, and the profile measuring device is located above or in the imaging tank. The three-dimensional moving device, the probe rotating device, the laser, the upper camera positioning device, the profile measuring device and the data collector are respectively connected to the computing platform. The three-dimensional imaging device has two imaging modes according to different imaging parts: an imaging mode in the tank and an imaging mode under the tank. Corresponding to the two imaging modes, the imaging tank adopts a first imaging tank and a second imaging tank. The imaging part is located on the bottom plate of the three-dimensional moving device, the height of the three-dimensional moving device and the imaging part is adjusted as a whole by the lifting platform to make the subject keep a more comfortable posture for imaging; the profile measuring device measures the profile of the imaging part to obtain the outer profile information of the imaging part and transmit it to the computing platform; the upper camera positioning device collects the planar image of the imaging part and transmits it to the computing platform, the operator determines the scanning area according to the planar image, the computing platform determines the movement path of the three-dimensional moving device driving the probe in the X axis and the Y axis according to the scanning area, and the movement speed of the X axis and the Y axis is a set value; the computing platform determines the movement speed and the movement path of the Z axis according to the profile information of the imaging part obtained by the profile measuring device and the movement path of the three-dimensional moving device in the X axis and the Y axis, so as to ensure that the imaging part is always in the effective imaging area of the vertical direction of the probe; the laser emits laser light which is uniformly irradiated to the imaging part through the optical fiber bundle to generate photoacoustic signals; in the imaging mode in the water tank, the first imaging water tank is used for imaging, the first imaging water tank is fixed on the bottom plate of the three-dimensional moving device, the imaging part, the probe and the light outlet of the optical fiber bundle are all located in the first imaging water tank, and the probe is directly coupled with the imaging part through the acoustic coupling agent in the first imaging water tank; in the imaging mode under the water tank, the second imaging water tank is used for imaging, the second imaging water tank is fixed on the imaging water tank lifting device, the bottom end of the imaging water tank lifting device is fixed on the bottom plate of the three-dimensional moving device, the bottom of the second imaging water tank is provided with a hole position, a light-transmitting and sound-transmitting flexible film is covered on the hole position, the imaging part is placed on the bottom plate of the three-dimensional moving device, and the second imaging water tank is placed on the imaging part; the height of the second imaging water tank is adjusted by adjusting the imaging water tank lifting device so that the light-transmitting and sound-transmitting flexible film at the bottom of the second imaging water tank is in contact with the imaging part; the probe and the light outlet of the optical fiber bundle are located in the second imaging water tank, the probe is coupled with the imaging part through the acoustic coupling agent in the second imaging water tank and the light-transmitting and sound-transmitting flexible film; the imaging part is covered with the acoustic coupling agent to ensure that it is attached to the light-transmitting and sound-transmitting flexible film, so as to avoid the existence of air between the probe and the imaging part and affect the imaging effect; the probe receives the photoacoustic signals, which are processed by the signal processor, collected by the data collector and transmitted to the computing platform to reconstruct two-dimensional and three-dimensional photoacoustic images; in the imaging mode in the water tank and the imaging mode under the water tank, when the imaging part is not in a horizontal state, the angle of the probe is adjusted by the probe rotating device to rotate the probe and then image the left and right sides of the imaging part, so as to further increase the imaging range.

[0013] Further, the present application also includes a light shielding shell, the three-dimensional moving device, the imaging table, the probe and the end of the optical fiber bundle are all located in the light shielding shell. In the water tank imaging mode, the first imaging water tank is fixed on the bottom plate of the three-dimensional moving device, the three-dimensional moving device is fixed in the light shielding shell, and the light shielding shell is fixed on the lifting table; in the water tank lower imaging mode, the second imaging water tank is fixed on the imaging water tank lifting device, the imaging water tank lifting device is fixed on the bottom plate of the three-dimensional moving device, the three-dimensional moving device is fixed in the light shielding shell, and the light shielding shell is fixed on the lifting table.

[0014] For different imaging parts, the corresponding imaging mode is selected. For the imaging parts such as hands and feet which can be directly placed into the imaging water tank, the water tank imaging mode is selected; for the imaging parts such as arms, legs and abdomen which are not easy to be placed into the imaging water tank, the water tank lower imaging mode is selected. Since the imaging parts such as hands, arms, feet and legs are not in a completely horizontal state, and the optimal depth range of the probe imaging is limited, it is necessary to image as much as possible based on the contour of the imaging part, so the present application has two positioning systems. One is that the subject measures the imaging part to be imaged by the contour measuring device before or during imaging, which is used to determine the contour information of the imaging parts such as hands, arms, feet and legs. The other is the upper camera positioning device, which aims to select the scanning range by the upper camera positioning device on the top of the device after the subject places the imaging parts such as hands, arms, feet and legs into the imaging area. The three-dimensional moving device is controlled by the upper camera positioning system and the contour measuring device to scan according to the set range. The probe has an effective imaging area, the horizontal plane is 8 cm, and the Z-axis height is 3-5 cm. If the imaging object deviates from the effective imaging area, the imaging effect will be poor. The imaging range of X-axis and Y-axis obtained by the upper camera positioning device on the calculation platform, and the X-axis and Y-axis will move at a set motion speed of 1 mm / s-10 mm / s, so the total imaging time can be obtained. Then the initial position and motion speed of the Z-axis are determined according to the contour information obtained by the contour measuring device and the total imaging time. So that the distance between the imaging part and the probe is always within the set range during the acquisition process.

[0015] The data collector adopts a multi-channel parallel high-frequency data collector.

[0016] The upper camera positioning device adopts a camera; the contour measuring device adopts an optical measuring device or an ultrasonic measuring device; the outer contour of the imaging part is measured before or during scanning imaging, and the measurement data are processed by the calculation platform to control the motion path of the probe; the motion path is planned before scanning or adjusted in real time during scanning to ensure that the distance between the probe and the imaging part is within the set range.

[0017] The application further comprises a signal processor, the probe is connected to the data collector through the signal processor, the probe receives the photoacoustic signal, the signal is amplified by the signal processor and collected by the data collector and transmitted to the computing platform.

[0018] One object of the application is to provide a human peripheral blood vessel photoacoustic three-dimensional imaging method.

[0019] The human peripheral blood vessel photoacoustic three-dimensional imaging method comprises the following steps: 1) The three-dimensional moving device and the imaging tank are located on the lifting platform, the height of the three-dimensional moving device, the imaging part and the imaging tank is adjusted as a whole through the lifting platform, so that the subject can keep a comfortable posture for imaging; 2) The profile measuring device measures the profile of the imaging part and transmits the profile information of the imaging part to the computing platform; 3) The overhead camera positioning device collects the planar image of the imaging part to the computing platform, the operator determines the scanning area according to the planar image, and the computing platform determines the movement path of the probe driven by the three-dimensional moving device on the X-axis and Y-axis according to the scanning area, and the movement speed of the X-axis and Y-axis is a set value; 4) The computing platform determines the movement speed and path of the Z-axis according to the profile information of the imaging part obtained by the profile measuring device and the movement path of the three-dimensional moving device on the X-axis and Y-axis, so that the movement of the three-axis combination of the three-dimensional moving device is consistent with the profile information of the imaging part, thereby ensuring that the distance between the probe and the imaging part is within the set range; 5) The laser emits laser light, which is uniformly irradiated to the imaging part through the optical fiber bundle to generate photoacoustic signals; 6) In the imaging mode in the tank: the first imaging tank is fixed on the bottom plate of the three-dimensional moving device, the probe and the light outlet of the optical fiber bundle are located in the first imaging tank, and the probe is directly coupled with the imaging part through the acoustic coupling agent in the first imaging tank; Or, in the imaging mode under the tank: the second imaging tank is placed on the imaging tank lifting device, the imaging tank lifting device is fixed on the bottom plate of the three-dimensional moving device, the bottom of the second imaging tank is provided with a hole position, and a light-transmitting and sound-transmitting flexible film covers the hole position; the height of the second imaging tank is adjusted by adjusting the imaging tank lifting device, so that the light-transmitting and sound-transmitting flexible film at the bottom of the second imaging tank contacts the imaging part; the probe and the light outlet of the optical fiber bundle are located in the second imaging tank, and the probe is coupled with the imaging part through the acoustic coupling agent in the second imaging tank and the light-transmitting and sound-transmitting flexible film; the imaging part is covered with the acoustic coupling agent to ensure that it is attached to the light-transmitting and sound-transmitting flexible film, so as to avoid the existence of air between the probe and the imaging part and affect the imaging effect; 7) The probe receives the photoacoustic signal, which is processed by the signal processor and collected by the data collector and transmitted to the computing platform to reconstruct two-dimensional and three-dimensional photoacoustic images; 8) In the two imaging modes of in-water imaging mode and under-water imaging mode, when the imaging part is not in a horizontal state, the angle of the probe is adjusted by the probe rotating device, the probe is rotated, and then the left and right sides of the imaging part are imaged, thereby further increasing the imaging range.

[0020] Advantages of the present application: The present application provides detailed vascular structure and blood flow dynamic information through the high resolution and functional monitoring capability of photoacoustic imaging, promotes early identification and treatment effect evaluation of common diseases such as diabetic foot and peripheral arterial disease, and simultaneously uses a mechanical system to bear a probe front end with high mass and stably operate to obtain a better photoacoustic imaging result; the present application is also expected to promote the portability of the equipment, reduce the equipment development cost, enable the equipment to be widely applied to clinical practice and community medical treatment, and improve the disease management level.

[0021] 1. Highly stable and accurate scanning imaging mode: the high-performance probe plus the front-end amplification module and other accessory components greatly increase the weight of the scanning head; the portal frame type three-dimensional moving device scanning architecture proposed in the present design can realize stable three-dimensional movement under a large load, and realize high-stability scanning at a relatively small cost.

[0022] 2. Multiple imaging modes convenient for clinical application: the unique structural characteristics of the three-dimensional moving device enable the hand, arm, foot and leg to be conveniently placed in the front and rear through space below the cross beam, which is particularly suitable for peripheral vascular imaging of multiple parts of the human body. For the hand and foot, the imaging region can be directly imaged by the in-water imaging mode. For the upper arm, leg and abdomen, etc. which are not suitable for being placed in the imaging region inside the imaging water tank, the under-water imaging mode is selected. The imaging of different height body parts such as hands and feet can be conveniently switched by the lifting platform. The imaging bed can also be increased to meet the imaging needs of the leg and other imaging parts, thereby expanding the application range of the equipment and enabling it to efficiently serve different types of clinical test requirements and research environments.

[0023] 3. The portal frame type three-dimensional moving device provides sufficient space for switching multiple photoacoustic imaging modes while ensuring the stability of the large load of the scanning probe, thereby improving the accuracy of photoacoustic imaging. However, the space provided by the portal frame type is relatively limited. The present application ensures that the imaging mode switching can be applied in the limited space through the arrangement of the imaging water tank and its lifting structure, thereby being applicable to the portal frame type layout. Therefore, the portal frame type layout and the water tank layout two technical means cooperate with and support each other, realize the switching of multiple clinical modes on the basis of stable support, and are applicable to the clinical scenarios that require accurate photoacoustic detection and constant switching of detection modes.

[0024] 4. Research and application potential: Due to the three-dimensional movement of the device driving the complex probe and scanning, the influence of human subjective factors during the operation of the handheld probe is eliminated, and the operation difficulty is reduced. At the same time, due to the use of two camera positioning devices, the imaging path of the xyz three-axis of the three-dimensional movement device is determined through the calculation platform, realizing the full automation of the scanning process and ensuring the repeatability of the test. The effects of chronic diseases and drug or surgical treatment can be better studied through the front and back comparison of the imaging results.

[0025] Scope of application: scenes that require accurate blood vessel evaluation, helping clinical and research personnel explore the prevention, diagnosis and treatment of vascular diseases. 1. Clinical diagnosis: used for peripheral arterial disease detection and evaluation, helping to develop treatment plans. Detecting microvascular lesions in diabetic patients, such as diabetic foot, for early intervention and management. Assessing venous dysfunction, such as varicose veins or thrombosis, for pre- and post-operative assessment. 2. Vascular function assessment: conduct tissue metabolic function tests, measure blood oxygen saturation, and assess vascular function and circulation. Identify vascular stenosis or dysfunction through functional imaging. 3. Chronic disease management: used for long-term monitoring of vascular health in chronic disease patients, dynamically assessing disease progression. 4. Research and development: used to study the biological mechanisms of vascular lesions, supporting the development of new therapies. Evaluate and verify the effectiveness of new drugs or treatment technologies. 5. Preventive health check-ups: used for vascular health screening of healthy individuals to detect potential risks early. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 Structure block diagram of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application; Figure 2 Front view of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application; Figure 3 Schematic diagram of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application imaging the hand; Figure 4 Schematic diagram of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application imaging the foot; Figure 5 Positioning principle diagram of the contour measurement device of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application imaging the foot; Figure 6 Actual operation schematic diagram of the water tank imaging mode of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application; Figure 7 Actual operation schematic diagram and representative result diagram of the water tank imaging mode of an embodiment of the human peripheral blood vessel photoacoustic three-dimensional imaging device of the present application; Figure 8These are representative results of the hand (left) and foot (right) of the photoacoustic three-dimensional imaging device for human peripheral blood vessels of the present invention; Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0028] like Figure 1 and 2 As shown, the photoacoustic three-dimensional imaging device for human peripheral blood vessels in this embodiment includes: a three-dimensional moving device, a probe rotating device, a lifting platform, a probe, a signal processor, a data acquisition unit, first and second imaging tanks, an imaging tank lifting device, a laser, an optical fiber bundle, an upper camera positioning device, a contour measuring device, and a computing platform. Because the photoacoustic signal received by the probe is relatively weak, it needs to be amplified before acquisition. To minimize signal loss, the best approach is to amplify the photoacoustic signal immediately after it is received by the probe. Furthermore, the shorter the distance between the probe and the signal processor, the better. In this invention, both the probe and the signal processor are fixed on a three-dimensional moving device, with a connection line of only 15cm between them, effectively reducing transmission loss. However, in this case, the combined mass of the probe and signal processor is relatively large, approximately 5kg. To maintain stable imaging quality, the system needs to stably move this mass of probe and signal processor components.

[0029] Therefore, the present application is to solve the problem of the stability of the system under the large mass probe and signal processor, and the special three-dimensional moving device is used, and the advantages of the three-dimensional moving device are reasonably utilized by the exchange of the first and second imaging water tanks, and the application direction is expanded. By replacing different imaging water tanks to adapt to the imaging requirements of different parts of the imaging water tank inside and the bottom of the imaging water tank. The first imaging water tank is directly fixed on the bottom plate of the three-dimensional moving device, the three-dimensional moving device is fixed in the light shielding shell, the light shielding shell is fixed on the lifting platform, and the imaging part can be directly placed in the first imaging water tank for imaging. The bottom of the second imaging water tank is fixed on the imaging water tank lifting device, and the imaging water tank lifting device is fixed on the bottom plate of the three-dimensional moving device. The lower part of the second imaging water tank is provided with a hole, and a light-transmitting and sound-transmitting flexible film is covered thereon, so that after the coupling agent is added in the second imaging water tank, the light-transmitting and sound-transmitting flexible film can cover the imaging part, so that the path from the probe to the imaging part is free of air to complete the imaging. The imaging water tank lifting device is fixed on both sides of the bottom of the second imaging water tank, and does not block the hole of the bottom of the second imaging water tank and the imaging part. At this time, the imaging part is placed on the bottom of the second imaging water tank for imaging. The height of the second imaging water tank is adjusted by the imaging water tank lifting device to adapt to the imaging requirements of different imaging parts under the imaging water tank. The setting of the two kinds of imaging water tanks can conveniently switch the imaging mode of the system in the imaging water tank and under the imaging water tank. At the same time, the sufficient imaging space under the top beam of the three-dimensional moving device can be better utilized.

[0030] In the light shielding shell on the lifting platform, the three-dimensional moving device is arranged, and the imaging area to be imaged is below the top beam in the two supports; the probe is installed on the probe rotating device, and the probe rotating device is installed on the translation structure of the three-dimensional moving device; the laser is connected to the light inlet of the optical fiber bundle, the optical fiber bundle adopts a one-to-ten optical fiber, and the light outlet of the optical fiber bundle is fixed at the front end of the probe; the probe is connected to the data collector through the signal processor; the upper camera positioning device is located above the imaging water tank, and the profile measuring device is located above or inside the imaging water tank; the three-dimensional moving device, the probe rotating device, the laser, the upper camera positioning device, the profile measuring device and the data collector are respectively connected to the computing platform. The upper camera positioning device adopts a camera; the profile measuring device adopts an optical method of a camera, or an ultrasonic method of an ultrasonic probe. The material of the light-transmitting and sound-transmitting flexible film is PVC; the sound coupling agent in the pool is water, and the sound coupling agent for coupling the light-transmitting and sound-transmitting flexible film and the imaging part is an ultrasonic medical coupling agent.

[0031] The three-dimensional imaging device has two imaging modes according to different imaging parts: water tank imaging mode and water tank imaging mode.

[0032] The imaging part and the imaging tank are located on the three-dimensional moving device. The height of the three-dimensional moving device and the imaging part and the imaging tank are adjusted as a whole by the lifting platform, so that the subject can keep a more comfortable posture for imaging. As shown in Figure 3 , the lifting platform is raised when imaging the hand, as shown in Figure 4 , the lifting platform is at the lowest end when imaging the foot, and as shown in Figure 5 , the profile measuring device measures the profile of the imaging part to obtain the profile information of the imaging part and transmits it to the computing platform; the overhead camera positioning device collects the planar image of the imaging part to the computing platform, and the operator determines the scanning area according to the planar image. The computing platform determines the movement path of the probe driven by the three-dimensional moving device in the X-axis and Y-axis according to the scanning area, the movement speed of the X-axis and Y-axis is a set value of 1mm / s, the X-axis and Y-axis are located in the horizontal plane, and the Z-axis is perpendicular to the horizontal plane; the computing platform determines the movement speed and path of the Z-axis according to the profile information of the imaging part obtained by the profile measuring device and the movement path of the three-dimensional moving device in the X-axis and Y-axis, so that the movement path of the three-axis combination of the three-dimensional moving device is consistent with the profile information of the imaging part, thereby ensuring that the imaging part is always in the effective imaging area of the vertical direction of the probe. The laser emits laser light with a wavelength of 1024nm, and a laser frequency of 10Hz is selected for use in experiments, and the energy is selected as 500mJ. The light is uniformly irradiated onto the imaging part through a one-to-ten optical fiber bundle, generating an optoacoustic signal; in the imaging mode in the tank, as shown in Figure 6 , the first imaging tank is used for imaging, the first imaging tank is installed on the base of the three-dimensional moving device, the three-dimensional moving device is fixed in the light-shielded shell, the light-shielded shell is fixed on the lifting platform, the imaging part, the probe and the light outlet of the optical fiber bundle are located in the first imaging tank, and the probe is directly coupled with the imaging part through the coupling agent inside the first imaging tank. In the imaging mode under the tank, as shown in Figure 7As shown, imaging is performed using a second imaging water tank, the second imaging water tank is fixed on an imaging water tank lifting device, the imaging water tank lifting device is installed on the bottom of the three-dimensional moving device, the three-dimensional moving device is fixed in a light shielding shell, the light shielding shell is fixed on the lifting platform, and the second imaging water tank is placed on the imaging site. The height of the second imaging water tank is adjusted by adjusting the imaging water tank lifting device, so that the light-transmitting and sound-transmitting flexible film at the bottom of the second imaging water tank is in contact with the imaging site. The light outlet of the probe and the optical fiber bundle is located inside the second imaging water tank, the probe is coupled with the imaging site through the coupling agent in the second imaging water tank and the light-transmitting and sound-transmitting flexible film; the imaging site covers the coupling agent to ensure that the light-transmitting and sound-transmitting flexible film is attached, so as to avoid air between the probe and the imaging site and affect the imaging effect; for example, when the arm is imaged, first, inject a sound coupling agent such as water into the second imaging water tank, and then cover the imaging area of the arm with a sound coupling agent such as an ultrasonic coupling agent. Then, the height of the second imaging water tank is adjusted by the imaging water tank lifting device, the arm is attached to the light-transmitting and sound-transmitting film at the bottom of the second imaging water tank, the probe enters the water to ensure that the distance from the arm meets the imaging requirements, and then the laser is turned on to perform imaging. The probe receives the photoacoustic signal, which is amplified by the signal processor and collected by the data collector, and is transmitted to the computing platform to reconstruct two-dimensional and three-dimensional photoacoustic images. In the two imaging modes of the imaging mode in the water tank and the imaging mode under the water tank, when the imaging site is not in a horizontal state, the angle of the probe is adjusted by the probe rotating device, the probe is rotated, and the left and right sides of the imaging site are imaged, thereby further increasing the imaging range.

[0033] The probe includes 256 self-focusing ultrasonic elements for receiving photoacoustic signals. The size of each ultrasonic element is 16x0.265mm, and the two elements are arranged with a gap of 0.3mm between the centers. The total length of the probe is 80mm, the self-focusing radius is 40mm, and the optimal imaging position is at a position 40±10mm away from the probe.

[0034] The specific form of the three-dimensional moving device includes: a support, a top beam, a sliding rail, a sliding groove, a sliding block, and a translation structure; wherein two supports are symmetrically placed on both sides, and the top ends of the two supports are connected by a top beam; the bottom ends of the two supports are respectively located on a sliding rail along the X axis, so that the two supports can move forward and backward along the X axis to form an X-axis translation structure; the surface of the top beam is provided with a sliding groove along the Y axis, and the sliding block moves along the sliding groove along the Y axis to form a Y-axis translation structure; the sliding block on the sliding groove is provided with a translation structure along the Z axis, the translation structure can move up and down along the Z axis to form a Z-axis translation structure, and moves left and right along the Y axis in the sliding groove; the three axes of the three-dimensional moving device are controlled by ball screws. For the X-axis translation structure, in addition to using ball screws, synchronous belts or gear and rack transmissions can be used. For the Y-axis translation structure, in addition to ball screws, synchronous belts or linear motors can also be used. For the Z-axis translation structure, in addition to ball screws, synchronous belts or linear motors can also be used.

[0035] The photoacoustic image reconstructed is shown as Figure 8 The result is a series of cross-sections of the imaging site in the Z-axis direction as the probe scans in the X-axis direction. The photoacoustic image is obtained by projecting the cross-sections into the xy plane using maximum amplitude projection after the cross-sections are stitched into a 3D volume. Figure 8 The left photoacoustic image of the hand is shown in Figure 8 The right photoacoustic image of the foot is shown in

[0036] Finally, it should be noted that the purpose of the embodiments disclosed is to help further understand the present application, but those skilled in the art can understand that various replacements and modifications are possible without departing from the spirit and scope of the present application and the appended claims. Therefore, the present application should not be limited to the disclosed embodiments, and the scope of the present application is defined by the scope of the claims.

Claims

1. A photoacoustic three-dimensional imaging device for human peripheral blood vessels, characterized in that, The imaging device includes: a three-dimensional moving device, a probe, a data acquisition unit, an imaging tank, a laser, an optical fiber bundle, an upper camera positioning device, a contour measurement device, and a computing platform; wherein, the probe is mounted on the translation structure of the three-dimensional moving device; the laser is connected to the light inlet of the optical fiber bundle, and the light outlet of the optical fiber bundle is fixed at the front end of the probe; the probe is connected to the data acquisition unit; the upper camera positioning device is located above the imaging tank, and the contour measurement device is located above or inside the imaging tank; the three-dimensional moving device, the laser, the upper camera positioning device, the contour measurement device, and the data acquisition unit are respectively connected to the computing platform; The three-dimensional imaging device has two imaging modes depending on the imaging location: the imaging mode inside the water tank and the imaging mode below the water tank. Corresponding to the two imaging modes, the imaging water tank adopts the first imaging water tank and the second imaging water tank respectively. The contour measurement device measures the contour of the imaging area, obtains the outer contour information of the imaging area, and transmits it to the computing platform; the upper camera positioning device acquires a planar image of the imaging area and transmits it to the computing platform, determines the scanning area based on the planar image, and the computing platform determines the movement path of the probe driven by the three-dimensional moving device along the X and Y axes based on the scanning area; the computing platform determines the movement speed and movement path along the Z axis based on the outer contour information; the laser emits a laser beam, which is uniformly irradiated onto the imaging area through an optical fiber bundle, generating a photoacoustic signal; the probe receives the photoacoustic signal, which is collected by the data acquisition device and transmitted to the computing platform to reconstruct two-dimensional and three-dimensional photoacoustic images.

2. The imaging device according to claim 1, characterized in that, It also includes a light-shielding shell, in which the ends of the three-dimensional moving device, the imaging tank, the probe, and the fiber bundle are all located.

3. The imaging device according to claim 1 or 2, characterized in that, The contour measuring device uses an optical or ultrasonic measuring method to measure the outer contour of the imaging area before or during scanning imaging. The measurement data is processed by a computing platform and used to control the motion path of the probe. The motion path is planned before scanning or adjusted in real time during scanning so that the distance from the probe to the imaging area is within a set range.

4. The imaging device according to claim 1, characterized in that, It also includes a lifting platform; the three-dimensional moving device, the imaging part and the imaging tank are located on the lifting platform, and the height of the three-dimensional moving device, the imaging part and the imaging tank are adjusted as a whole by the lifting platform; in the imaging mode inside the tank, the first imaging tank is located on the base plate of the three-dimensional moving device, and the imaging part is located inside the first imaging tank; in the imaging mode below the tank, the second imaging tank is fixed on the imaging tank lifting device, the imaging tank lifting device is installed on the base plate of the three-dimensional moving device, and the imaging part is located below the second imaging tank and on the base plate of the three-dimensional moving device.

5. The imaging device according to claim 1, characterized in that, It also includes a signal processor. The probe is connected to the data acquisition unit via the signal processor. The probe receives photoacoustic signals, which are amplified by the signal processor and then collected by the data acquisition unit and transmitted to the computing platform.

6. The imaging device according to claim 1, characterized in that, It also includes a probe rotation device, on which the probe is mounted. The probe rotation device is mounted on the translation structure of the three-dimensional moving device and is connected to the computing platform. In two imaging modes, the probe angle is adjusted by the probe rotation device to image the left and right sides of the imaging area.

7. An imaging method for the photoacoustic three-dimensional imaging device for human peripheral blood vessels according to claim 1, characterized in that, The imaging method includes the following steps: 1) The three-dimensional moving device and the imaging tank are located on the lifting platform. The height of the three-dimensional moving device, the imaging part and the imaging tank are adjusted as a whole by the lifting platform. 2) The contour measurement device performs contour measurement on the imaging area, obtains the contour information of the imaging area, and transmits it to the computing platform; 3) The upper camera positioning device acquires a planar image of the imaging area and sends it to the computing platform. The scanning area is determined based on the planar image. The computing platform determines the movement path of the probe driven by the three-dimensional moving device on the X-axis and Y-axis based on the scanning area. The movement speed on the X-axis and Y-axis is a set value. 4) The computing platform determines the movement speed and movement path of the Z-axis based on the contour information of the imaging part obtained by the contour measurement device and the movement path of the three-dimensional moving device on the X and Y axes, so that the three-axis composite movement of the three-dimensional moving device is consistent with the contour information of the imaging part, and the distance from the probe to the imaging part is within the set range. 5) The laser emits a laser beam, which is uniformly irradiated onto the imaging area through the fiber bundle, generating a photoacoustic signal; 6) The three-dimensional imaging device has two imaging modes depending on the imaging part: the imaging mode inside the water tank and the imaging mode below the water tank. Corresponding to the two imaging modes, the imaging water tank adopts the first imaging water tank and the second imaging water tank respectively. 7) The probe receives photoacoustic signals, which are processed by the signal processor, then collected by the data acquisition unit and transmitted to the computing platform to reconstruct two-dimensional and three-dimensional photoacoustic images; 8) In both imaging modes, when the imaging area is not horizontal, the probe angle is adjusted by the probe rotation device, and the probe is rotated to image the left and right sides of the imaging area.

8. The imaging method according to claim 7, characterized in that, Select the appropriate imaging mode for different imaging areas: for imaging areas that can be easily placed in the imaging tank, select the in-tank imaging mode; for imaging areas that are not easy to place in the imaging tank, select the submerged imaging mode.

9. The imaging method according to claim 8, characterized in that, Imaging mode in the water tank: The first imaging water tank is installed on the base plate of the three-dimensional moving device. The imaging part, the probe and the light outlet of the fiber bundle are all located in the first imaging water tank. The probe is coupled to the imaging part through the acoustic coupling agent inside the first imaging water tank.

10. The imaging method according to claim 8, characterized in that, In the underwater imaging mode: the second imaging tank is fixed on the imaging tank lifting device, which is installed on the base plate of the three-dimensional moving device. The bottom of the second imaging tank has holes covered with a light-transmitting and sound-transmitting flexible film. The height of the second imaging tank is adjusted by adjusting the imaging tank lifting device so that the light-transmitting and sound-transmitting flexible film at the bottom of the second imaging tank contacts the imaging part. The light outlet of the probe and the fiber bundle is located inside the second imaging tank. The probe is coupled to the imaging part through the acoustic coupling agent in the second imaging tank and the light-transmitting and sound-transmitting flexible film. The imaging part is covered with acoustic coupling agent to adhere to the light-transmitting and sound-transmitting flexible film.

Images