An apparatus for measuring photoacoustic endoscopic imaging resolution and depth

Abstract

The application discloses a device for measuring photoacoustic endoscopic imaging resolution and depth, and belongs to the technical field of biomedical imaging detection, which comprises a vertical plate, a height adjusting mechanism is arranged on the vertical plate, the height adjusting mechanism is connected with a liftable probe clamping assembly, a bottom plate is fixedly arranged at one end of the vertical plate, a scanning imaging rotating motor is arranged on one side of the bottom plate, an output end of the scanning imaging rotating motor is connected with a coupling medium container, a base body is installed in the coupling medium container, a plurality of through holes in the shape of Archimedes spiral are arranged on the base body, and a plurality of target wires for providing photoacoustic signal contrast are arranged in the through holes. The application can simulate a complex tissue environment, obtain multi-directional and multi-scale imaging results, and thus be used for evaluating the resolution and imaging depth of a photoacoustic endoscopic system, and is suitable for detecting and standardizing evaluating different types of photoacoustic endoscopic equipment.

Description

Technical Field

[0001] This invention belongs to the field of biomedical imaging and detection technology, and more specifically, relates to a device for measuring the resolution and depth of photoacoustic endoscopic imaging. Background Technology

[0002] Photoacoustic endoscopy is an emerging hybrid imaging technology that combines the high contrast of optical imaging with the deep penetration of ultrasound imaging, enabling high-resolution detection of tissue structure and function. In recent years, this technology has attracted widespread attention due to its ability to penetrate deep into internal cavities or blood vessels to acquire high-resolution images, demonstrating great potential in areas such as cardiovascular disease, early tumor diagnosis, and minimally invasive surgical navigation.

[0003] In practical applications, photoacoustic endoscopic imaging systems require a coupling medium to transmit photoacoustic signals, reducing interface reflection and energy loss. However, there is currently a lack of unified testing methods and standards for assessing imaging depth. Existing detection devices mostly use water or conventional coupling fluids, whose optical scattering and absorption characteristics differ significantly from those of real biological tissues, leading to discrepancies between imaging depth results and clinical applications. Furthermore, existing target structure designs are relatively simple, making it difficult to comprehensively simulate the photoacoustic response of tissues at different depths.

[0004] Meanwhile, the spatial resolution of an imaging system is a key indicator for evaluating its performance and determining its ability to identify minute lesions. However, current methods for evaluating the resolution of photoacoustic endoscopy are still imperfect, typically using standard resolution boards or targets with periodic grid structures for testing. These traditional targets have significant limitations: firstly, the target distribution is singular, with most targets only providing limited resolution information at fixed points or along straight lines, failing to reflect the system's imaging capabilities in complex spatial structures; secondly, probe alignment is difficult: existing devices lack precise control over the positioning and adjustment of the probe and target, often relying on manual operation, resulting in poor repeatability and large errors. Furthermore, most existing resolution testing methods are self-made in laboratories, exhibiting diverse forms, and have not yet formed a universally compatible and widely applicable testing platform. Summary of the Invention

[0005] The main objective of this invention is to provide an apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging, thereby addressing the problems described in the background section.

[0006] According to a first aspect of the present invention, an apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging is provided, comprising a vertical plate, wherein a height adjustment mechanism is provided on the vertical plate, the height adjustment mechanism is connected to a liftable probe clamping assembly, a base plate is fixedly provided at one end of the vertical plate, a scanning imaging rotary motor is provided on one side of the base plate, the output end of the scanning imaging rotary motor is connected to a coupling medium container for injecting coupling medium, a substrate is installed inside the coupling medium container, and a plurality of through holes distributed in an Archimedean spiral pattern are provided on the substrate, wherein a plurality of target wires for providing photoacoustic signal comparison are passed through the through holes.

[0007] In a particular embodiment of the present invention, a transducer is provided below the height adjustment mechanism.

[0008] In a specific embodiment of the present invention, the height adjustment mechanism includes a motor, a lead screw, and a motor mounting plate. The motor is fixedly mounted on the motor mounting plate. The output end of the motor is connected to one end of the lead screw via a coupling. The other end of the lead screw is connected to the base plate. The probe clamping assembly is movably disposed on the lead screw and can move back and forth along the length direction of the lead screw.

[0009] In a specific embodiment of the present invention, guide rods are symmetrically arranged on both sides of the lead screw, and the two ends of the guide rods are respectively connected to the motor fixing plate and the base plate. The guide rods are connected in cooperation with the probe clamping assembly.

[0010] In a specific embodiment of the present invention, the probe clamping assembly includes a movable stage, a connecting plate is provided on the movable stage, a protrusion is provided in the middle of the connecting plate, the protrusion has a through hole, a probe that can move axially is provided in the through hole, a first circular hole communicating with the through hole is provided on the connecting plate, and at least four screw holes are symmetrically provided on the protrusion.

[0011] In a specific embodiment of the present invention, the protruding post and the connecting plate are integrally formed.

[0012] In a specific embodiment of the present invention, an assembly plate is provided at one end of the mobile platform near the height adjustment mechanism, and the assembly plate has a plurality of assembly holes that cooperate with the height adjustment mechanism.

[0013] In a specific embodiment of the present invention, the base includes multiple support columns and two disks, the two disks being symmetrically arranged at both ends of the support columns, the through hole being provided on the disk, the disk having a second circular hole in the middle, and the disk also having a slot communicating with the through hole, the diameter of the slot being smaller than the diameter of the through hole, and the depth of the slot being smaller than the depth of the through hole.

[0014] In a specific embodiment of the present invention, the top of the coupling medium container is recessed inward to form a receiving groove, which is used to hold a mixture of milk and ink as a coupling medium. The bottom of the receiving groove has a protrusion at the middle position that mates with a second circular hole. The bottom of the coupling medium container is recessed inward to form a connecting hole, which is connected to the output end of the scanning imaging rotary motor.

[0015] In a particular embodiment of the present invention, the target wire is made of carbon fiber or copper wire.

[0016] One of the above-described technical solutions of the present invention has at least one of the following advantages or beneficial effects:

[0017] (1) Multidimensional target distribution: Through spiral or array structure, it is possible to simulate the signal distribution in complex tissue environment and fully reflect the resolution capability of the imaging system;

[0018] (2) Realistic simulation of optical properties: The mixture of milk and ink is used instead of traditional coupling agent to better simulate the optical properties of biological tissues and obtain imaging depth results that are closer to actual applications;

[0019] (3) High precision and repeatability: The height adjustment mechanism works in conjunction with the scanning imaging rotary motor to ensure high precision and repeatability of probe position and angle adjustment, avoiding errors caused by manual positioning;

[0020] (4) Strong compatibility: The modular design is compatible with photoacoustic probes of different models and sizes, and has strong expandability and versatility;

[0021] (5) Standardization potential: The device and testing method can promote the establishment of a standardized evaluation system, improve the comparability of results from different devices and laboratories, and provide a unified quality control platform for the research and development and clinical application of photoacoustic endoscopy.

[0022] In summary, this invention effectively overcomes the limitations of traditional measurement methods and provides a testing method that can truly reflect the tissue environment, which is of great significance for promoting the performance optimization and clinical translation of photoacoustic endoscopic imaging equipment. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0024] Figure 1 This is a schematic diagram of a device for measuring the resolution and depth of photoacoustic endoscopic imaging in one embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of the substrate in one embodiment of the present invention;

[0026] Figure 3This is a schematic diagram of the height adjustment mechanism in one embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of the probe clamping assembly in one embodiment of the present invention;

[0028] Figure 5 This is a cross-sectional view of the coupling medium container in one embodiment of the present invention. Detailed Implementation

[0029] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0030] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0031] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" and "second" may explicitly or implicitly include one or more features.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection or a connection that allows communication between the two components; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components, an indirect connection, or an interaction between two components.

[0034] The following disclosure provides many different implementations or examples for different ways of implementing the present invention.

[0035] Reference Figures 1 to 5 As shown, a device for measuring the resolution and depth of photoacoustic endoscopic imaging is provided, including a vertical plate 1, a height adjustment mechanism 2 on the vertical plate 1, a height adjustment mechanism 2 connected to a liftable probe clamping assembly 3, a base plate 4 fixed at one end of the vertical plate 1, a scanning imaging rotary motor 5 on one side of the base plate 4, a coupling medium container 6 connected to the output end of the scanning imaging rotary motor 5, a substrate 7 installed inside the coupling medium container 6, and a plurality of through holes 71 distributed in an Archimedean spiral pattern on the substrate 7, through which multiple target wires for providing photoacoustic signal comparison are passed.

[0036] In one embodiment of the present invention, a transducer is provided below the height adjustment mechanism 2.

[0037] In one embodiment of the present invention, the height adjustment mechanism 2 includes a motor 21, a lead screw 22 and a motor fixing plate 25. The motor 21 is fixedly mounted on the motor fixing plate 25. The output end of the motor 21 is connected to one end of the lead screw 22 through a coupling 23. The other end of the lead screw 22 is connected to the base plate 4. The probe clamping assembly 3 is movably disposed on the lead screw 22 and can move back and forth along the length direction of the lead screw 22.

[0038] Furthermore, guide rods 24 are symmetrically arranged on both sides of the lead screw 22. The two ends of the guide rods 24 are respectively connected to the motor fixing plate 25 and the base plate 4. The guide rods 24 are connected to the probe clamping assembly 3.

[0039] In one embodiment of the present invention, the probe clamping assembly 3 includes a movable stage 31, a connecting plate 32 is provided on the movable stage 31, a protrusion 33 is provided in the middle of the connecting plate 32, a through hole 331 is provided in the protrusion 33, a probe that can move axially is provided in the through hole 331, a first circular hole communicating with the through hole 331 is provided on the connecting plate 32, and at least four screw holes 332 are symmetrically provided on the protrusion 33.

[0040] Furthermore, the protruding post 33 and the connecting plate 32 are integrated into one unit.

[0041] Furthermore, an assembly plate 34 is provided at one end of the moving platform 31 near the height adjustment mechanism 2, and the assembly plate 34 has multiple assembly holes that cooperate with the height adjustment mechanism 2.

[0042] In one embodiment of the present invention, the substrate 7 includes multiple support columns 72 and two disks 73. The two disks 73 are symmetrically arranged at both ends of the support columns 72. A through hole 71 is provided on the disk 73. A second circular hole 74 is provided in the middle of the disk 73. A slot 75 communicating with the through hole 71 is also provided on the disk 73. The diameter of the slot 75 is smaller than the diameter of the through hole 71, and the depth of the slot 75 is smaller than the depth of the through hole 71. Preferably, the substrate 7 can be a multi-layer phantom module.

[0043] Furthermore, the top of the coupling medium container 6 is recessed inward with a receiving groove 61, which is used to hold a mixture of milk and ink as a coupling medium. The bottom of the receiving groove 61 has a protrusion 62 that is connected to a second circular hole 74. The bottom of the coupling medium container 6 is recessed inward with a connecting hole 63, which is connected to the output end of the scanning imaging rotary motor 5.

[0044] In one embodiment of the present invention, the target wire is made of carbon fiber or copper wire.

[0045] In this embodiment, a device for measuring the resolution and depth of photoacoustic endoscopic imaging is provided, the structure of which is as follows: Figure 1 As shown, it includes a height adjustment mechanism 2, a probe clamping assembly 3, a scanning imaging rotary motor 5, a coupling medium container 6, and a substrate 7.

[0046] The structure of probe clamping assembly 3 is as follows Figure 4 As shown, before the experiment, the probe is inserted through the first circular hole and extended to a certain length, and then fixed through four symmetrical screw holes 332. The probe is fixedly set in the through hole 331.

[0047] Prosthetic preparation: such as Figure 2 As shown, in the substrate 7, the target wire (such as carbon fiber or copper wire) is passed through the through hole 71 distributed by the Archimedean spiral. The slot hole 75 communicating with the through hole 71 is fixed with ultraviolet glue (also known as UV glue or shadowless glue). The probe can be moved axially in the second circular hole 74 at the top of the substrate 7 by the height adjustment mechanism 2.

[0048] The substrate 7 is fixedly connected to the protrusion 62 in the middle of the accommodating groove 61 of the coupling medium container 6 through the second circular hole 74 at the bottom of the substrate 7, while the connection hole 63 at the bottom of the coupling medium container 6 is fixedly connected to the output end of the scanning imaging rotary motor 5.

[0049] During the experiment, the ultrasonic transducer probe was fixed inside the through hole 331 and secured with screws through the screw hole 332, ensuring that the photoacoustic receiving end face of the transducer was directly facing the target wire. A mixture of milk and ink was injected into the coupling medium container 6 as the coupling fluid for coupling the ultrasonic signal. The height adjustment structure 2 remained stationary, meaning the probe was at a fixed height. The scanning imaging rotary motor 5 drove the substrate 7 to rotate, causing each target wire to pass through the transducer detection area sequentially. By recording the imaging results of the photoacoustic system on different target wires, the resolution performance at a fixed focal plane can be obtained, which is particularly suitable for evaluating the lateral resolution of the system.

[0050] The advantages of this embodiment are its simple structure, stable testing process, and ability to achieve multi-point resolution detection by rotating the target while keeping the probe height constant, which facilitates comparison of imaging clarity at the same depth level.

[0051] Example 2: Three-dimensional resolution measurement under adjustable height conditions

[0052] In this embodiment, the device structure is the same as in Embodiment 1, except that the height adjustment structure 2 is used to drive the probe to move up and down in the vertical direction, thereby changing the imaging focal plane of the probe.

[0053] In the experiment, the substrate 7 with the target wire fixed is first mounted on the scanning imaging rotary motor 5. The scanning imaging rotary motor 5 drives the target to rotate at a constant angular velocity, realizing circumferential scanning of the target wire; at the same time, the height adjustment structure 2 drives the probe to move gradually in the vertical direction, with each step ranging from 0.1 mm to 0.5 mm. By controlling the coordinated movement of the two motors, photoacoustic signals at different depth levels can be obtained.

[0054] As the probe scans layer by layer, the target wires in substrate 7 are detected at different depths, forming three-dimensional resolution test data. The lateral resolution can be evaluated by reconstructing the acquired data using a photoacoustic imaging system.

[0055] The advantages of this embodiment are: the automatic adjustment of the probe height is achieved by driving the motor 21, which can quickly complete the multi-layer imaging resolution test; combined with rotational scanning, the all-round response of the target wire is obtained, which is suitable for the imaging performance analysis of the system in the depth direction.

[0056] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A device for measuring the resolution and depth of photoacoustic endoscopic imaging, characterized in that, The system includes a vertical plate (1), on which a height adjustment mechanism (2) is provided. The height adjustment mechanism (2) is connected to a liftable probe clamping assembly (3). A base plate (4) is fixedly provided at one end of the vertical plate (1). A scanning imaging rotary motor (5) is provided on one side of the base plate (4). The output end of the scanning imaging rotary motor (5) is connected to a coupling medium container (6). A substrate (7) is installed inside the coupling medium container (6). The substrate (7) is provided with several through holes (71) distributed in an Archimedean spiral shape. Multiple target wires for providing photoacoustic signal comparison are passed through the through holes (71). The coupling medium container (6) contains a coupling medium. The scanning imaging rotary motor (5) and the height adjustment mechanism (2) work together to drive the probe to perform multi-depth and omnidirectional scanning of the target wires.

2. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 1, characterized in that, A transducer is provided below the height adjustment mechanism (2).

3. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 1, characterized in that, The height adjustment mechanism (2) includes a motor (21), a lead screw (22) and a motor fixing plate (25). The motor (21) is fixedly installed on the motor fixing plate (25). The output end of the motor (21) is connected to one end of the lead screw (22) through a coupling (23). The other end of the lead screw (22) is connected to the base plate (4). The probe clamping assembly (3) is movably arranged on the lead screw (22). The probe clamping assembly (3) can move back and forth along the length direction of the lead screw (22).

4. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 3, characterized in that, Guide rods (24) are symmetrically arranged on both sides of the lead screw (22). The two ends of the guide rods (24) are respectively connected to the motor fixing plate (25) and the base plate (4). The guide rods (24) are connected to the probe clamping assembly (3).

5. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 1, characterized in that, The probe clamping assembly (3) includes a movable stage (31), a connecting plate (32) is provided on the movable stage (31), a protrusion (33) is provided in the middle of the connecting plate (32), a through hole (331) is provided on the protrusion (33), an axially movable probe is provided in the through hole (331), a first circular hole communicating with the through hole (331) is provided on the connecting plate (32), and at least four screw holes (332) are symmetrically provided on the protrusion (33).

6. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 5, characterized in that, The protruding post (33) and the connecting plate (32) are integrated into one piece.

7. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 5, characterized in that, The movable platform (31) is provided with an assembly plate (34) at one end near the height adjustment mechanism (2), and the assembly plate (34) has a plurality of assembly holes that cooperate with the height adjustment mechanism (2).

8. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 1, characterized in that, The base (7) includes multiple support columns (72) and two disks (73). The two disks (73) are symmetrically arranged at both ends of the support columns (72). The through hole (71) is provided on the disk (73). A second circular hole (74) is provided in the middle of the disk (73). The disk (73) is also provided with a slot (75) communicating with the through hole (71). The diameter of the slot (75) is smaller than the diameter of the through hole (71), and the depth of the slot (75) is smaller than the depth of the through hole (71).

9. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 8, characterized in that, The top of the coupling medium container (6) is recessed inward with a receiving groove (61), which is used to hold a mixture of milk and ink as a coupling medium. The bottom of the receiving groove (61) has a protrusion (62) that is connected to a second circular hole (74) at the middle position. The bottom of the coupling medium container (6) is recessed inward with a connecting hole (63), which is connected to the output end of the scanning imaging rotary motor (5).

10. The apparatus for measuring the resolution and depth of photoacoustic endoscopic imaging according to claim 1, characterized in that, The target wire is made of carbon fiber or copper wire.

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