A device for locating sentinel lymph nodes in breast cancer

Abstract

The present invention discloses a device for locating sentinel lymph nodes in breast cancer. The locating device includes a laser emitter and a probe device covered on the laser emitter. The probe device includes a flexible circuit substrate and multiple groups of piezoelectric micro-ultrasonic transducers arranged in an array on the flexible circuit substrate. Two adjacent groups of piezoelectric micro-ultrasonic transducers are spliced ​​together. Each piezoelectric micro-ultrasonic transducer includes multiple ultrasonic units. Each ultrasonic unit encloses a housing space. The housing space contains a lead zirconate titanate block bonded to the ultrasonic unit. By integrating the lead zirconate titanate block and the piezoelectric micro-ultrasonic transducer on the flexible circuit substrate, the probe device can fully cover the breast lymphatic drainage area, implement dynamic tracking of the trajectory of the lymph node tracer in the lymphatic vessels, realize dynamic tracking of the entire process, and accurately identify and locate the position of the sentinel lymph node.

Description

Technical Field

[0001] The invention belongs to the field of medical technology, and in particular relates to a positioning device for sentinel lymph nodes of breast cancer. Background Art

[0002] The incidence of breast cancer has been increasing year by year, ranking first among female malignancies and becoming one of the major diseases that seriously threatens women's health. Regional lymph node metastasis is the main route of breast cancer metastasis, with approximately 70% of cases occurring via the axillary lymph nodes (ALN). The traditional treatment for breast cancer is modified radical mastectomy, which involves ipsilateral mastectomy and axillary lymph node dissection (ALND). Axillary lymph nodes are first removed, followed by pathological examination to determine whether metastasis has occurred, which serves as a reference for prognosis and whether further chemotherapy is warranted. However, ALND is not only unnecessary for breast cancer patients without axillary lymph node metastasis, but it can also lead to complications such as upper limb lymphedema, pain, and motor and sensory impairment. Therefore, determining whether axillary lymph node metastasis has occurred before ALND is an important factor in determining breast cancer staging, selecting surgical options, and assessing patient prognosis.

[0003] Currently, a sentinel lymph node biopsy (SLNB) is commonly used to clinically determine whether breast cancer has metastasized to the axillary lymph nodes. This involves first locating the sentinel lymph node (SLN), then performing a biopsy to determine the surgical plan. If no metastasis is present, ALND is not necessary. Prior to SLNB, the location of the SLN must be determined. Current SLN localization methods primarily include dye-based, radionuclide-based, and combined dye-and-nuclide methods.

[0004] However, existing SLN localization and detection technologies cannot accurately locate SLN in real time and dynamically. The location and number of SLNs in different patients vary greatly, which is affected by the experience of the surgeon and can easily lead to surgical failure or omission, affecting the reliability of SLN biopsy. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a positioning device for sentinel lymph nodes of breast cancer, aiming to solve the technical problem of how to accurately locate sentinel lymph nodes in real time and dynamically.

[0006] To achieve the above objectives, the present invention provides the following technical solutions: a device for locating sentinel lymph nodes in breast cancer, comprising a laser transmitter and a probe device covered on the laser transmitter and used to track a tracer injected into the subcutaneous tissue of the human areola to generate a photoacoustic signal, and simultaneously receive the photoacoustic signal to accurately locate the sentinel lymph nodes. The probe device comprises a flexible circuit substrate and a plurality of groups of piezoelectric micro-ultrasonic transducers arranged in an array on the flexible circuit substrate, wherein two adjacent groups of piezoelectric micro-ultrasonic transducers are spliced ​​together, each of the piezoelectric micro-ultrasonic transducers comprises a plurality of ultrasonic units, each of the ultrasonic units enclosing a housing space, wherein a lead zirconate titanate block bonded to the ultrasonic unit is embedded in the housing space.

[0007] Furthermore, the ultrasonic units are arranged in a hexagonal shape.

[0008] Furthermore, it also includes a main control unit for controlling the laser emitter to emit laser, an amplification and filtering unit for amplifying and filtering the photoacoustic signal received by the probe device and transmitting the filtered photoacoustic signal to the main control unit, and an imaging unit for connecting to the main control unit to display the tracer movement trajectory.

[0009] Furthermore, the piezoelectric micro ultrasonic transducer is made of silicon-based material processed by micro-electromechanical system.

[0010] Furthermore, each of the plurality of groups of piezoelectric micro-ultrasonic transducers tracking the tracer satisfies the following relationship:

[0011] R n -R1=C(t n -t1)

[0012] Where R n is the position of the nth piezoelectric micro-ultrasonic transducer; R1 is the position of the first piezoelectric micro-ultrasonic transducer, C is the air propagation velocity; t n is the absolute transmission time from the sound source signal to the nth piezoelectric micro-ultrasonic transducer; t1 is the absolute transmission time from the sound source signal to the first piezoelectric micro-ultrasonic transducer.

[0013] Furthermore, the preparation method of the probe device comprises the following steps:

[0014] S01: Divide the flexible circuit substrate into a plurality of array elements, and mount a piezoelectric micro ultrasonic transducer on each array element position of the flexible circuit substrate at 280-350° C.;

[0015] S02: Drilling a hole in the flexible circuit substrate and placing the lead zirconate titanate block in the hole;

[0016] S03: Bonding the lead titanate block to the piezoelectric micro ultrasonic transducer through an adhesive.

[0017] Furthermore, the step S03 further includes:

[0018] The lead titanate block and the piezoelectric micro ultrasonic transducer bonded by an adhesive are placed in a baking oven with a baking temperature of 50-70° C. and a baking time of 30 minutes.

[0019] The beneficial effects of the present invention are as follows: compared with the prior art, a breast cancer sentinel lymph node positioning device in the present invention emits a pulsed laser of a specific frequency through a laser transmitter, thereby interacting with a tracer injected into the subcutaneous part of the human areola, and stimulating the tracer to emit a photoacoustic signal according to the photoacoustic effect; by selecting a probe formed by a composite of a lead zirconate titanate block and a piezoelectric micro-ultrasonic transducer, a larger emission sound pressure can be provided by the lead zirconate titanate block, thereby enhancing the intensity and penetration of the ultrasonic signal; by selecting a piezoelectric micro-ultrasonic transducer and integrating it on a flexible circuit substrate, the formed probe device has the characteristics of small size and low power consumption, and is easier to integrate into portable or minimally invasive medical equipment; by integrating both the lead zirconate titanate block and the piezoelectric micro-ultrasonic transducer on a flexible circuit substrate, the probe device can fully cover the breast lymph drainage area, implement dynamic tracking of the lymph node tracer in the lymphatic vessels, realize dynamic tracking of the entire process, and accurately identify and locate the sentinel lymph node position.

[0020] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the purpose, technical solutions and beneficial effects of the present invention more clear, the present invention provides the following drawings for illustration:

[0022] Figure 1 A schematic structural diagram of a method and device for locating sentinel lymph nodes in breast cancer according to one embodiment of the present invention;

[0023] Figure 2 A schematic structural diagram of a probe device according to an embodiment of the present invention;

[0024] Figure 3 The present invention provides a flow chart of a process for preparing a probe device according to an embodiment of the present invention.

[0025] Figure Number:

[0026] 1-Laser transmitter;

[0027] 2-probe device; 21-flexible circuit substrate; 22-piezoelectric micro ultrasonic transducer; 221-ultrasonic unit; 222-accommodation space; 23-lead zirconate titanate block;

[0028] 3- Main control unit;

[0029] 4- amplification and filtering unit;

[0030] 5- Imaging unit. DETAILED DESCRIPTION

[0031] like Figures 1 to 2 As shown, this embodiment provides a device for locating sentinel lymph nodes in breast cancer, comprising a laser emitter 1 and a probe device 2. The probe device 2 is mounted on the laser emitter 1. The probe device 2 can be used to track a tracer injected into the subcutaneous area of ​​the human areola to generate a photoacoustic signal, and simultaneously receive the photoacoustic signal to accurately locate the sentinel lymph node. Specifically, the probe device 2 includes a flexible circuit substrate 21 and multiple groups of piezoelectric micro-ultrasonic transducers 22. Each group of piezoelectric micro-ultrasonic transducers 22 is arranged in an array on the flexible circuit substrate 21. Two adjacent groups of piezoelectric micro-ultrasonic transducers 22 are spliced ​​together. Each piezoelectric micro-ultrasonic transducer 22 includes multiple ultrasonic units 221. Each ultrasonic unit 221 encloses a housing space 222. A lead zirconate titanate block 23 is embedded in the housing space 222. The lead zirconate titanate block 23 is bonded to the ultrasonic unit 221. A pulsed laser of a specific frequency is emitted by the laser emitter 1, thereby interacting with the subcutaneous tracer injected into the human areola, and stimulating the tracer to emit a photoacoustic signal according to the photoacoustic effect; by selecting a probe formed by a composite of a lead zirconate titanate block 23 and a piezoelectric micro-ultrasonic transducer 22, a larger emission sound pressure can be provided by the lead zirconate titanate block 23, thereby enhancing the intensity and penetration of the ultrasonic signal; by selecting the piezoelectric micro-ultrasonic transducer 22 and integrating it on the flexible circuit substrate 21, the formed probe device has the characteristics of small size and low power consumption, and is easier to integrate into portable or minimally invasive medical equipment; by integrating both the lead zirconate titanate block 23 and the piezoelectric micro-ultrasonic transducer 22 on the flexible circuit substrate 21, the probe device can fully cover the breast lymph drainage area, implement dynamic tracking of the trajectory of the lymph node tracer in the lymphatic vessels, realize dynamic tracking of the entire process, and accurately identify and locate the position of the sentinel lymph nodes.

[0032] In the present application, by setting up multiple groups of miniature ultrasonic transducers 22, multiple photoacoustic signals can be received synchronously, multiple positioning can be achieved, and the positioning accuracy is greatly improved.

[0033] In the present application, during radical breast cancer surgery, a tracer is injected intradermally into the areola in advance. Since the tracer has good lymphotropism, it can quickly reach the lymphatic tissue. The composite flexible probe formed by the lead zirconate titanate block 23 and the piezoelectric micro ultrasonic transducer 22 in the present application can dynamically monitor the trajectory of the tracer in the lymphatic vessels in real time. The first lymph node reached by the tracer is the sentinel lymph node, and dynamic tracking is achieved to accurately identify and locate the position of the sentinel lymph node.

[0034] In the present application, the probe device 2 is capable of operating within a wider frequency band, can adapt to the detection requirements of different depths and tissues, and supports multiple working modes (such as pulse echo, Doppler, etc.), thereby providing richer diagnostic information, realizing ultrasound / photoacoustic dual-modality positioning of sentinel lymph nodes, and improving the positioning accuracy.

[0035] In this application, the laser emitter 1 uses a nanosecond pulsed laser and includes a tunable parametric oscillator module, which allows for precise wavelength modulation in the near-infrared band, emitting pulsed light with a pulse width of 5ns and a frequency of 10Hz. Preferably, in this application, the laser emitter 1 uses a 780nm laser wavelength, which is then coupled to a two-fiber bundle and then irradiated onto the surface of biological tissue or a phantom.

[0036] Preferably, the tracer is nanocarbon.

[0037] Preferably, the ultrasonic unit 221 is hexagonal. By configuring the ultrasonic unit 221 as a hexagon, it can be easily assembled. Of course, in this embodiment, the shape of the ultrasonic unit 221 can also be configured as other shapes according to actual conditions and specific needs, and this is not a sole limitation.

[0038] Further, see Figure 1 As shown, the positioning device also includes a main control unit 3, an amplification and filtering unit 4, and an imaging unit 5. The main control unit 3 can be used to control the laser emitter 1 to emit laser light. The amplification and filtering unit 4 can be used to amplify and filter the photoacoustic signals received by the probe device 2, and transmit the filtered photoacoustic signals to the main control unit 3. The imaging unit 5 can be connected to the main control unit 3 to display the movement trajectory of the tracer. In this way, because the multiple groups of piezoelectric micro-ultrasonic transducers 22 synchronously receive multiple photoacoustic signals, the received photoacoustic signals may be weak in intensity. The amplification and filtering unit 4 can amplify and filter the probe photoacoustic signals, making the photoacoustic signals clear and easy to distinguish. Subsequently, the filtered photoacoustic signals are transmitted to the main control unit 3, which in turn transmits the photoacoustic signals to the imaging unit 5, thereby displaying the corresponding tracer trajectory.

[0039] Furthermore, the piezoelectric micro-ultrasonic transducer 22 is fabricated using a micro-electromechanical system (MEMS) to process silicon-based materials. In this application, the MEMS is a high-tech device that integrates micro-mechanical and electronic components. It is a conventional MEMS in the prior art and will not be described in detail here. The piezoelectric micro-ultrasonic transducer fabricated using this MEMS is small in size, low in power consumption, and easily integrated into portable or minimally invasive medical devices.

[0040] Furthermore, each of the multiple groups of piezoelectric micro-ultrasonic transducers 22 tracks the tracer and satisfies the following relationship:

[0041] R n -R1=C(t n -t1)

[0042] Where R n is the position of the nth piezoelectric micro-ultrasonic transducer; R1 is the position of the first piezoelectric micro-ultrasonic transducer, C is the air propagation velocity; t n is the absolute transmission time from the sound source signal to the nth piezoelectric micro-ultrasonic transducer; t1 is the absolute transmission time from the sound source signal to the first piezoelectric micro-ultrasonic transducer.

[0043] Specifically, in order to better explain the positioning principle of the piezoelectric micro ultrasonic transducer, in this application, three piezoelectric micro ultrasonic transducers are used for positioning explanation:

[0044] See also Figure 1 As shown, assuming that the position coordinates of the tracer are (X, Y); the position coordinates of the single piezoelectric micro ultrasonic transducer are (X1, 0), (X2, 0), and (X3, 0), respectively, then:

[0045] R2-R1=C(t2-t1)=[(X2-X) 2 +Y 2 ] 1 / 2 -[(X1-X) 2 +Y 2 ] 1 / 2

[0046] R3-R1=C(t3-t1)=[(X3-X) 2 +Y 2 ] 1 / 2 -[(X1-X) 2 +Y 2 ] 1 / 2

[0047] By calculating with the above formula, multiple positioning of multiple piezoelectric micro-ultrasonic transducers can be achieved, thereby greatly improving the positioning accuracy.

[0048] Further, see Figure 2 As shown, the preparation method of the probe device 2 includes the following steps:

[0049] S01: Divide the flexible circuit substrate 21 into a plurality of array elements, and mount the piezoelectric micro ultrasonic transducer 22 at each array element position of the flexible circuit substrate 21 at 280-350° C.;

[0050] S02: Drilling a hole in the flexible circuit substrate 21 and placing the lead zirconate titanate block 23 in the hole;

[0051] S03: Bond the lead titanate block 23 to the piezoelectric micro ultrasonic transducer 22 through an adhesive.

[0052] In the present application, by selecting a flexible circuit substrate 21, the flexible circuit substrate 21 has a high flexibility, so that it can better adapt to the patient's organs such as breasts and other structures. Specifically, the piezoelectric micro ultrasonic transducer 22 is electrically connected to the flexible circuit substrate 21 through a metal guide wire; by opening a hole in the flexible circuit substrate 21, a receiving space 222 is formed, which facilitates the placement of the lead zirconate titanate block 23 in the receiving space 222, and the lead titanate block 23 is bonded to the piezoelectric micro ultrasonic transducer 22 by an adhesive. The ultrasonic transducer 22 is bonded to achieve physical connection, forming a composite sensor strip as a whole. By integrating the lead zirconate titanate block 23 and the piezoelectric micro ultrasonic transducer 22 on the flexible circuit substrate 21, the lead zirconate titanate block 23 can provide a larger emission sound pressure, thereby enhancing the strength and penetration of the ultrasonic signal, so that the piezoelectric micro ultrasonic transducer 22 can dynamically track the trajectory of the lymph node tracer in the lymphatic vessels, realize dynamic tracking of the entire process, and accurately identify and locate the position of the sentinel lymph nodes.

[0053] Furthermore, the step S03 further includes:

[0054] The lead titanate block 23 and the piezoelectric micro ultrasonic transducer 22 bonded by an adhesive are placed in a baking oven at a baking temperature of 50-70° C. for 30 minutes.

[0055] In the present application, baking is performed to dry out excess moisture in the adhesive, thereby preventing the water vapor from adversely affecting the operation of the piezoelectric micro ultrasonic transducer.

[0056] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A breast cancer sentinel lymph node positioning device, characterized in that: The invention relates to a probe device comprising a laser emitter and a cover mounted on the laser emitter for tracking a tracer injected into the subcutaneous tissue of a human areola to generate a photoacoustic signal, and simultaneously receiving the photoacoustic signal to accurately locate a sentinel lymph node. The probe device comprises a flexible circuit substrate and a plurality of piezoelectric micro-ultrasonic transducers arranged in an array on the flexible circuit substrate. Two adjacent piezoelectric micro-ultrasonic transducers are spliced ​​together. Each of the piezoelectric micro-ultrasonic transducers comprises a plurality of ultrasonic units, each of which encloses a housing space. The housing space contains a lead zirconate titanate block bonded to the ultrasonic unit. The ultrasonic unit is arranged in a hexagonal shape. The tracking of the tracer by the plurality of piezoelectric micro-ultrasonic transducers satisfies the following relationship: R n -R1=C(t n -t1) Where R n is the position of the nth piezoelectric micro-ultrasonic transducer; R1 is the position of the first piezoelectric micro-ultrasonic transducer, C is the air propagation velocity; t n is the absolute transmission time from the sound source signal to the nth piezoelectric micro-ultrasonic transducer; t1 is the absolute transmission time from the sound source signal to the first piezoelectric micro-ultrasonic transducer.

2. The breast cancer sentinel lymph node positioning device according to claim 1, characterized in that: The system also includes a main control unit for controlling the laser emitter to emit laser light, an amplification and filtering unit for amplifying and filtering the photoacoustic signal received by the probe device and transmitting the filtered photoacoustic signal to the main control unit, and an imaging unit for connecting to the main control unit to display the tracer movement trajectory.

3. The breast cancer sentinel lymph node positioning device according to claim 2, characterized in that: The piezoelectric micro ultrasonic transducer is made of silicon-based material processed by a micro-electromechanical system.

4. The breast cancer sentinel lymph node positioning device according to claim 1, characterized in that: The preparation method of the probe device comprises the following steps: S01: Divide the flexible circuit substrate into a plurality of array elements, and mount a piezoelectric micro ultrasonic transducer on each array element position of the flexible circuit substrate at 280-350° C.; S02: Drilling a hole in the flexible circuit substrate and placing the lead zirconate titanate block in the hole; S03: Bonding the lead zirconate titanate block to the piezoelectric micro ultrasonic transducer through an adhesive.

5. The breast cancer sentinel lymph node positioning device according to claim 4, characterized in that: The step S03 further includes: The lead zirconate titanate block and the piezoelectric micro ultrasonic transducer bonded by an adhesive are placed in a baking oven with a baking temperature of 50-70° C. and a baking time of 30 minutes.

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