A 1.5D intracavitary ultrasound microprobe and imaging method

Abstract

The present invention relates to a 1.5D intracavitary ultrasound microprobe and imaging method. The probe includes an acoustic lens, a matching layer, a piezoelectric layer, a backing, a flexible circuit board, and a connecting cable. The piezoelectric layer, backing, and flexible circuit board form an array imaging array having multiple groups of spaced array elements, each group of array elements including a central array element N, array element N-1, and array element N-2. Array elements N-1 and N-2 are connected in parallel, and central array element N is connected in parallel with parallel array elements N-1 and N-2 via a capacitor. Each group of array elements requires only one coaxial line. Without increasing the size of the probe or the number of transmission cables, the present invention achieves a phase / time delay between the ultrasonic wave excited by array element N and the parallel array elements N-1 and N-2 through a capacitor and a connection method requiring only one coaxial line, thereby improving the sound field distribution in space and the imaging quality. This achieves high-performance ultrasonic imaging of a 1.5D ultrasonic endoscope probe with a simple structure and low cost.

Description

Technical Field

[0001] The present invention belongs to the field of clinical medical technology, and particularly relates to a 1.5D intracavitary ultrasound microprobe, and also relates to an imaging method using the 1.5D intracavitary ultrasound microprobe. Background Art

[0002] Ultrasound endoscopy is a technology that uses ultrasound to image the human body's internal cavities. A small-sized ultrasound probe is placed at the front end of an interventional catheter and inserted into the esophagus, gastrointestinal tract, bronchi, etc. to perform real-time scanning and imaging, and assist in diagnosis and treatment.

[0003] Existing intracavitary ultrasound probes are limited by the size of the cavity and are mostly one-dimensional linear, convex, or phased array probes, resulting in insufficient resolution in the thickness slice direction. Furthermore, a key application of multi-element intracavitary ultrasound probes is ultrasound-guided puncture or treatment within the body. Current probe technology limits the accuracy of intracavitary ultrasound diagnosis and treatment.

[0004] Furthermore, traditional intracavitary probes typically connect each element to a positive and negative terminal, with the negative terminal typically sharing a common ground, requiring a coaxial cable. Traditional 1.5D probes connect the upper and lower elements and the center element separately, requiring two coaxial cables. Therefore, there is an urgent need for a 1.5D ultrasound endoscopic probe that achieves high-performance ultrasound imaging without increasing probe size or the number of transmission cables. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide an improved 1.5D intracavitary ultrasound microprobe.

[0006] The present invention also relates to an imaging method using a 1.5D intracavity ultrasound microprobe.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A 1.5D intracavitary ultrasound microprobe includes an acoustic lens, a matching layer, a piezoelectric layer, a backing, a flexible circuit board, and a connecting cable. The piezoelectric layer, backing, and flexible circuit board form an array imaging system. The array imaging system has multiple groups of separated array elements. Each group of array elements includes a central array element N and array element N-1 and array element N-2 separated from the ends of the central array element N. Array element N-1 and array element N-2 are connected in parallel. The central array element N is connected in parallel with the parallel array elements N-1 and N-2 via a capacitor. Each group of array elements requires only one coaxial line.

[0009] Preferably, the widths of the array elements in each group of array elements are equal, which facilitates the subsequent control of the sound field and facilitates batch cutting and processing.

[0010] According to one specific implementation and preferred aspect of the present invention, the length ratio of the central element N, element N-1, and element N-2 in each group of array elements is 2:1:1. This optimizes the phase delay between the ultrasonic waves excited by element N and the parallel elements N-1 and N-2, thereby improving the spatial sound field distribution and imaging quality.

[0011] Preferably, the array element N-1 and the array element N-2 are spaced equidistant from the center array element N. A symmetrical structure is more conducive to adjusting the sound field distribution of the probe in space.

[0012] Preferably, a blank gap is formed between each two adjacent array elements, and the blank gap is filled with a high molecular polymer, which can effectively ensure the probe array element structure and avoid damage to the structure caused by bending, collision, and oxidation.

[0013] Furthermore, the high molecular polymer is epoxy resin or rubber, which has stable and reliable performance, convenient operation and low price.

[0014] According to another specific implementation and preferred aspect of the present invention, each group of array elements is connected to the negative electrode through a conductive matching layer or bonding wire. In this example, using a conductive matching layer to connect the negative electrodes of the array elements to the common ground is more convenient to implement and can simplify the structure.

[0015] Preferably, the backing is made of a conductive material and is located between the flexible circuit board and the piezoelectric layer. In this way, the flexible circuit board and the piezoelectric layer can be electrically connected via the backing.

[0016] Alternatively, the backing is made of a non-conductive material, and the backing is located at the bottom of the flexible circuit board.

[0017] In addition, the flexible circuit board is also provided with lead wires and pads, which facilitates the circuit conduction of each group of array elements.

[0018] Another technical solution of the present invention is: an ultrasonic imaging method, which uses the above-mentioned 1.5D intracavitary ultrasonic microprobe and includes the following steps:

[0019] 1) According to the measurement requirements, the delay required by array element N-1 and array element N-2 is set to ΔT. The size of the capacitor C connected in parallel in the circuit can be determined by the following formula:

[0020] C=-R×ln((EV) / E) / ΔT Formula (1)

[0021] In formula (1), R is the impedance of the probe array element, E is the excitation voltage, and V is the capacitor charge and discharge voltage. At the same time, according to formula (1), the capacitance value required for each array element to be connected in parallel is first determined to complete the production and packaging of the endoscopic probe;

[0022] 2) Each probe is stimulated in turn, and then the echo signal is received for beamforming and subsequent processing. The received echo signal is also delayed after passing through the circuit.

[0023] T = -R × C × ln (V / U) Formula (2)

[0024] In formula (2), T is the specific delay time, R is the impedance of the probe array element, C is the capacitance value, V is the capacitor charge and discharge voltage, and U is the signal strength. At the same time, during the echo processing process, due to the delay generated by the probe circuit and combined with the calculation result of formula (2), the echo of the array element is time compensated.

[0025] Due to the implementation of the above technical solution, the present invention has the following advantages compared with the prior art:

[0026] Without increasing the size of the probe or the number of transmission cables, the present invention achieves phase / time delay between the ultrasonic waves excited by array element N and parallel N-1 and N-2 through capacitance and a connection method requiring only one coaxial line, thereby improving the sound field distribution in space, improving the imaging quality, and realizing high-performance ultrasonic imaging of a 1.5D ultrasonic endoscope probe. At the same time, the structure is simple and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the main view of the 1.5D intracavitary ultrasound microprobe of the present invention;

[0028] Figure 2 for Figure 1 Schematic diagram of the top view of the middle array element;

[0029] Figure 3 for Figure 1 Schematic diagram of the connection method of the probe;

[0030] Among them: 1. Acoustic lens; 2. Matching layer; 3. Piezoelectric layer; 4. Backing; 5. Flexible circuit board; C, capacitor; N, center array element; N-1, N-2, array elements. DETAILED DESCRIPTION

[0031] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar modifications without violating the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0033] 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 the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0034] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0035] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0036] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0037] like Figure 1 As shown, the 1.5D intracavity ultrasound microprobe according to this embodiment includes an acoustic lens 1, a matching layer 2, a piezoelectric layer 3, a backing 4, a flexible circuit board 5, and a connecting cable.

[0038] Specifically, the piezoelectric layer 3, the backing 4, and the flexible circuit board 5 form an array imaging, which has multiple groups of separated array elements. Each group of array elements includes a central array element N, and array element N-1 and array element N-2 separated from the two ends of the central array element N.

[0039] Combine Figure 2 As shown, the widths of the elements in each group of elements are equal.

[0040] The length ratio of the central element N, element N-1, and element N-2 in each array element group is 2:1:1. This optimizes the phase delay between the ultrasonic waves excited by element N and the parallel elements N-1 and N-2, thereby improving the spatial sound field distribution and imaging quality.

[0041] In this example, the distances between array element N-1 and array element N-2 and the center array element N are equal.

[0042] A gap is formed between each set of adjacent array elements, and is filled with a polymer. This effectively secures the probe array element structure and prevents damage from bending, collision, and oxidation.

[0043] Specifically, the high molecular polymer is epoxy resin or rubber, which has stable and reliable performance, convenient operation and low price.

[0044] Combine Figure 3 As shown, the array element N-1 and the array element N-2 are connected in parallel, the central array element N is connected in parallel with the parallel array element N-1 and the array element N-2 through the capacitor C, and each group of array elements only requires one coaxial line.

[0045] Each group of array elements is connected to the negative electrode through a conductive matching layer 2 or a bonding wire. In this example, the conductive matching layer 2 is used to connect the negative electrodes of the array elements to the common ground, which is more convenient to implement and can simplify the structure.

[0046] The backing 4 is made of a conductive material and is located between the flexible circuit board 5 and the piezoelectric layer 3. In this way, the flexible circuit board and the piezoelectric layer can be connected through the backing.

[0047] In addition, the flexible circuit board is also provided with lead wires and pads, which facilitates the circuit conduction of each group of array elements.

[0048] In summary, the ultrasonic imaging method of this embodiment is as follows:

[0049] 1) According to the measurement requirements, the delay required by array element N-1 and array element N-2 is set to ΔT. The size of the capacitor C connected in parallel in the circuit can be determined by the following formula:

[0050] C=-R×ln((EV) / E) / ΔT Formula (1)

[0051] In formula (1), R is the impedance of the probe array element, E is the excitation voltage, and V is the capacitor charge and discharge voltage. At the same time, according to formula (1), the capacitance value required for each array element to be connected in parallel is first determined to complete the production and packaging of the endoscopic probe;

[0052] 2) Each probe is stimulated in turn, and then the echo signal is received for beamforming and subsequent processing. The received echo signal is also delayed after passing through the circuit.

[0053] T = -R × C × ln (V / U) Formula (2)

[0054] In formula (2), T is the specific delay time, R is the impedance of the probe array element, C is the capacitance value, V is the capacitor charge and discharge voltage, and U is the signal strength. At the same time, during the echo processing process, due to the delay generated by the probe circuit and combined with the calculation result of formula (2), the echo of the array element is time compensated.

[0055] Therefore, without increasing the size of the probe and the number of transmission cables, this embodiment achieves the phase / time delay of the ultrasonic waves excited by array element N and parallel N-1 and N-2 through capacitance and connection with only one coaxial line, thereby improving its sound field distribution in space, improving imaging quality, and realizing high-performance ultrasonic imaging of the 1.5D ultrasonic endoscope probe. At the same time, the structure is simple and the cost is low.

[0056] The above detailed description of the present invention is intended to enable persons familiar with the art to understand the contents of the present invention and implement them. It does not limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A 1.5D intracavitary ultrasound microprobe comprising an acoustic lens, a matching layer, a piezoelectric layer, a backing, a flexible printed circuit board, and a connecting cable, wherein the piezoelectric layer, backing, and flexible printed circuit board form an array imaging system having multiple groups of spaced array elements, each group of array elements comprising a central array element N and array elements N-1 and N-2 spaced from the central array element N at opposite ends, wherein the array elements N-1 and N-2 are connected in parallel, characterized in that: The central array element N is connected in parallel with the array element N-1 and the array element N-2 via a capacitor, and each group of the array elements requires only one coaxial line; Assuming the delay required by elements N-1 and N-2 is ΔT, the size of the capacitor C connected in parallel in the circuit can be determined by the following formula: C=-R×ln((EV) / E) / ΔT Formula (1) In formula (1), R is the impedance of the probe array element, E is the excitation voltage, and V is the capacitor charge and discharge voltage; T = -R × C × ln (V / U) Formula (2) In formula (2), T is the specific delay time, R is the impedance of the probe array element, C is the capacitance value, V is the capacitor charge and discharge voltage, and U is the signal strength. During the echo processing, due to the delay generated by the probe circuit and combined with the calculation result of formula (2), the echo of the array element is time compensated.

2. The 1.5D intracavitary ultrasound microprobe according to claim 1, characterized in that: The widths of the array elements in each group of array elements are equal.

3. The 1.5D intracavitary ultrasound microprobe according to claim 1, wherein: The length ratio of the central array element N, array element N-1, and array element N-2 in each group of array elements is 2:1:

1.

4. The 1.5D intracavitary ultrasound microprobe according to claim 3, wherein: The array element N-1 and the array element N-2 are spaced equidistant from the central array element N.

5. The 1.5D intracavitary ultrasound microprobe according to claim 1, wherein: A blank gap is formed between every two adjacent groups of array elements, and a high molecular polymer is filled in the blank gap.

6. The 1.5D intracavitary ultrasound microprobe according to claim 5, characterized in that: The high molecular polymer is epoxy resin or rubber.

7. The 1.5D intracavitary ultrasound microprobe according to claim 1, characterized in that: Each group of array elements is connected to a common ground with the negative electrode through a conductive matching layer or a bonding wire.

8. The 1.5D intracavitary ultrasound microprobe according to claim 1, characterized in that: The backing is made of a conductive material and is located between the flexible circuit board and the piezoelectric layer.

9. The 1.5D intracavitary ultrasound microprobe according to claim 1, characterized in that: The backing is made of non-conductive material and is located at the bottom of the flexible circuit board.

10. An ultrasonic imaging method, characterized in that: The ultrasonic imaging method uses the 1.5D intracavitary ultrasonic microprobe according to any one of claims 1 to 9, and the ultrasonic imaging method comprises the following steps: 1) According to the measurement requirements, the delay required by array element N-1 and array element N-2 is set to ΔT. The size of the capacitor C connected in parallel in the circuit can be determined by the following formula: C=-R×ln((EV) / E) / ΔT Formula (1) In formula (1), R is the impedance of the probe array element, E is the excitation voltage, and V is the capacitor charge and discharge voltage. At the same time, according to formula (1), the capacitance value required for each array element to be connected in parallel is first determined to complete the production and packaging of the endoscopic probe; 2) Each probe is stimulated in turn, and then the echo signal is received for beamforming and subsequent processing. The received echo signal is also delayed after passing through the circuit. T = -R × C × ln (V / U) Formula (2) In formula (2), T is the specific delay time, R is the impedance of the probe array element, C is the capacitance value, V is the capacitor charge and discharge voltage, and U is the signal strength. At the same time, during the echo processing process, due to the delay generated by the probe circuit and combined with the calculation result of formula (2), the echo of the array element is time compensated.

Images