Ablation monitoring system and method based on real-time temperature and image feedback data

Abstract

The invention relates to an ablation monitoring system based on real-time temperature and image feedback data, and the system comprises a temperature collection device which collects first temperature change information in a tumor internal ablation process in real time; the ablation device is configured to provide energy required by tumor ablation and is provided with a model of a color and temperature corresponding relation of a tumor surface image, and the model is called a first relation model for short; the image acquisition device acquires tumor surface ablation process image information in real time, which is called a first image for short; the temperature identification device is used for matching the color of each pixel of the first image with the first relation model to obtain the second temperature change information; the three-dimensional model simulation device is used for establishing a tumor three-dimensional model; and displaying the first temperature change information and the second temperature change information on the three-dimensional model in real time. By monitoring the temperature change in the tumor and the temperature change of the surface in the ablation process, the tumor ablation boundary is accurately controlled, and transition ablation is prevented.

Description

Technical Field

[0001] The invention relates to an ablation monitoring system and method based on real-time temperature and image feedback data, belonging to the technical field of ablation. Background Art

[0002] In recent years, ablation technology has begun to be widely used in the treatment of various solid tumors, especially in the treatment of liver cancer and lung cancer. During microwave ablation, doctors are usually unable to intuitively monitor the temperature changes of the ablated tissue and its surrounding organs at risk. Generally, CT images are taken in stages during the ablation process, and then the doctor judges the current ablation results based on his own experience. In order to ensure that the ablation results meet expectations, the accuracy of judgment is generally improved by increasing the number of CT scans, which increases the risk of patients being exposed to radiation, increases the economic burden on patients, and increases the complexity of the doctor's surgical process. Moreover, there is a lag between CT images and the actual ablation results, and the ablation results cannot be monitored in real time.

[0003] In addition, the size and shape of the thermal field of tumor ablation are not only affected by the shape of the antenna, the transmission power and effective output power, and the action time, but are also closely related to thermal properties such as the thermal conductivity and blood perfusion rate of the tumor tissue. Due to the complexity of the human physiological environment and the limitations of the measurement methods, the different sizes and irregularities of tumors, the problems of thermal dosimetry parameters, temperature measurement, and thermal field conformity in the body have not been effectively solved. Doctors cannot predict the range of the thermal field before surgery, and there is no effective means to detect the range of the thermal field during surgery, so the ablation boundary cannot be accurately controlled. Summary of the invention

[0004] The technical problem to be solved by the present invention is to effectively control the ablation process of the entire tumor by establishing temperature monitoring inside and on the surface of multiple tumor tissues.

[0005] In order to solve the above technical problems, on the one hand, the present invention proposes an ablation monitoring system based on real-time temperature and image feedback data, comprising: A temperature acquisition device collects the first temperature change information of the tumor during the ablation process in real time; an ablation device, configured to provide energy required to ablate a tumor, and equipped with a model of a corresponding relationship between color and temperature of a tumor surface image, referred to as a first relationship model; An image acquisition device, which acquires image information of the tumor surface ablation process in real time, referred to as the first image; a temperature recognition device, used for matching the color of each pixel of the first image with the first relationship model to obtain the second temperature change information; The three-dimensional model simulation device establishes a three-dimensional model of the tumor; and displays the first temperature change information and the second temperature change information on the three-dimensional model in real time.

[0006] On the other hand, the present invention also proposes an ablation monitoring method based on real-time temperature and image feedback data, which is applied to the above monitoring system and includes the following steps: Real-time acquisition of first temperature change information during tumor ablation; Collecting the first image in real time and obtaining second temperature change information; The ablation range is monitored according to the first temperature change information and the second temperature change information.

[0007] The present invention monitors the temperature changes inside and on the surface of the tumor during the ablation process to accurately control the tumor ablation boundary and prevent excessive ablation. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 Schematic diagram of the structure of the ablation needle in an embodiment of the present invention.

[0009] Figure 2 yes Figure 1 Schematic diagram of the cross section at the inner rod.

[0010] Figure 3 It is a schematic diagram of the structure of multi-point temperature measurement on the ablation needle.

[0011] Figure numerals: 1, ablation needle; 2, needle rod; 3, sleeve; 4, channel; 5, first elastic outer sleeve; 6, second elastic outer sleeve 7, temperature measuring element. DETAILED DESCRIPTION

[0012] In clinical treatment, ablation surgery lacks appropriate real-time monitoring means, resulting in an uncontrollable ablation process. Intermittent ablation is required, and the ablation range is observed intermittently through images to ensure the safety and reliability of the ablation process and to ensure that there is no excessive ablation. During tumor ablation surgery, in order to monitor the temperature changes of the tumor target tissue during the ablation process, doctors generally use side temperature measurement, or some design temperature measurement points on the ablation needle, but neither of the above two temperature measurement methods can reflect the local temperature changes of the tumor target tissue in real time. The temperature measurement points designed on some ablation needles can only measure the temperature of the cooling water, and cannot measure the temperature changes of the tumor at all. In addition, in the prior art, it is not possible to display the temperature changes of the tumor on the ablation system in a timely and accurate manner, and observe the degeneration trend of the entire tumor. The technical solution of the present invention can intuitively observe the changes in the local temperature of the tumor during the ablation process.

[0013] The technical solution proposed by the present invention is further described in detail below in conjunction with embodiments and drawings, but the implementation mode of the present invention is not limited thereto. Example

[0014] This embodiment provides an ablation monitoring system based on data fusion of real-time temperature and real-time image feedback, including A temperature acquisition device collects the first temperature change information of the tumor during the ablation process in real time; an ablation device, configured to provide energy required to ablate a tumor, and equipped with a model of a corresponding relationship between color and temperature of a tumor surface image, referred to as a first relationship model; An image acquisition device acquires image information of the tumor surface ablation process in real time, referred to as the first image; and establishes second temperature change information of the tumor surface ablation process according to the first image; a temperature recognition device, used for matching the color of each pixel of the first image with the first relationship model to obtain second temperature change information; The three-dimensional model simulation device establishes a three-dimensional model of the tumor; and displays the first temperature change information and the second temperature change information on the three-dimensional model in real time.

[0015] The following is a detailed description of each module of the system: Temperature collection device The temperature acquisition device in this embodiment can be an invasive temperature measurement method, such as using a side-by-side temperature measurement method to obtain the temperature change of the internal tissue of the tumor. It can also use a non-temperature measurement method, such as ultrasonic temperature measurement.

[0016] In order to measure the temperature changes of multiple points of the internal tissue of the tumor and minimize tissue trauma, the temperature acquisition device in this embodiment can adopt the following design: like Figure 1-3 As shown, the ablation needle 1 in this embodiment is provided with a double-layer outer sleeve consisting of a first elastic outer sleeve and a second elastic outer sleeve on the outside of the needle rod 2, and the double-layer outer sleeve is close to the needle rod. At least one temperature measuring element 7 and a wire connecting the temperature measuring element are provided between the first elastic outer sleeve 5 and the second elastic outer sleeve 6. The temperature measuring element 7 is equidistantly distributed axially along the outside of the needle rod 2, and the wire extends along the length direction of the needle rod 2 to the handle of the ablation needle 1. The temperature measuring element is preferably a thermocouple, and the thermocouple can be fixed between the first elastic outer sleeve 5 and the second elastic outer sleeve 6 by double-layer coated thermocouple technology to achieve 4000V voltage internal insulation. The ablation needle handle is provided with an interface for connecting the wire, which is used to read the temperature measurement value of the thermocouple in real time.

[0017] The first elastic outer sleeve 5 and the second elastic outer sleeve 6 can be made of medical polymer materials. In the present embodiment, they are preferably made of polyimide (POLYIMIDE), which is customarily referred to as PI. It is a type of polymer material with good biocompatibility and stability. It can maintain the stability of its structure and performance at high temperatures, has very good electrical insulation, and high mechanical properties such as tensile strength, bending strength and impact strength.

[0018] The temperature change information collected by the temperature collection device is referred to as first temperature change information.

[0019] Image acquisition device It is used to collect image information of the tumor surface ablation process in real time. We refer to this image information as the first image.

[0020] The tumor tissue surface image as the first image can be acquired through a natural cavity or an artificial cavity. Taking the acquisition through an artificial cavity as an example, Figure 2 As shown, the image acquisition device includes an ablation needle, a sleeve is arranged on the needle rod of the ablation needle, and a channel for the free passage of the shooting element is arranged on the sleeve. The shooting element in this embodiment is preferably an endoscope. When the ablation needle 1 is inserted into the tumor tissue for ablation, the endoscope is inserted from the channel 4 to collect the color change of the surface image of the tumor tissue, which corresponds to the first relationship model pre-stored in the ablation system, so as to display the temperature change of the surface of the tumor target tissue in real time. In some cases, the endoscope can also be used to shoot the surface of the tumor target tissue through the natural cavity to obtain the first image.

[0021] Ablation Device The ablation device in this embodiment is a microwave ablation system, which is equipped with a model database of the corresponding relationship between the color and temperature of the tumor tissue surface image. We refer to this model database as the first relationship model for short. This database is obtained by the following experimental method: The steps of the experimental method are as follows: The first step is to place the ex vivo tissue in a light-proof box to simulate the ablation environment of human liver tissue, so that the subsequent endoscopic shooting results are consistent with the actual ablation process. Multiple temperature measurement points are set on the surface of the ex vivo tissue, and thermocouples are set on the temperature measurement points to measure the temperature of the temperature measurement points through the thermocouples.

[0022] In this embodiment, the ex vivo tissue is a pig liver that was isolated within 4 hours. Before ablation, the pig liver was stored in an electric constant temperature water tank to maintain the liver tissue temperature at 36.5±2°C.

[0023] The second step is to insert the ablation needle through the box into the ex vivo tissue to simulate the ablation process of the ex vivo tissue. It should be noted that in order to collect image information of temperature changes on the surface of the ex vivo tissue, the ablation needle should not be inserted too deep; the existing ablation needle does not have a shooting function, such as Figure 1 and 2As described above, this embodiment improves the existing ablation needle 1, installs a sleeve 3 on the needle shaft 2, and opens a channel 4 for the endoscope to freely enter and exit on the sleeve 3. The endoscope channel 4 can move with the ablation needle, so that the endoscope can display the ablation process in real time during the actual operation. This embodiment is also used to simulate this shooting process through the above settings. By adjusting the endoscope lens angle and the distance from the endoscope lens to the needle tip, the endoscope is fixed in place, and the image of the tissue surface can be captured at this time.

[0024] The endoscope in this embodiment adopts the Guantai series submillimeter ultra-fine fiber endoscope, which has the functions of fiber optic image transmission and light guide. The probe has good flexibility and a smaller diameter, and can be used to detect through curved and narrow channels. It can be directly observed through the eyepiece, and can also be connected to the display screen through the USB OTG interface to capture and process images, which is easy to operate. The endoscope has a field of view of 70°-120°, a one-way bending angle of the probe of ≥150°, a depth of field of 5-50mm, and a fiber optic light guide function, which is convenient for lighting.

[0025] It should be noted that due to the limitations of the endoscope's field of view, bending angle and depth of field, if the endoscope and ablation needle are fixed as one, the image collected by the endoscope will be unclear during the movement of the ablation needle, or the tumor target area will partially or completely move out of the endoscope lens during the movement, making it impossible to accurately puncture.

[0026] The third step is to extend the endoscope from the channel 4, and adjust the lens angle of the endoscope and the distance from the endoscope lens to the needle tip so that an image of the ex vivo tissue surface within the visible range can be captured.

[0027] Step 4: Set the ablation parameters of the ablation needle and ablate the ex vivo tissue. During the ablation process, take photos of the ex vivo tissue to obtain multiple sets of first images. According to the RGB value of each pixel in the first image, the corresponding relationship between the ex vivo tissue surface temperature value and the RGB value is obtained, which is referred to as the first relationship model.

[0028] The process of obtaining the first relationship model can be summarized as follows: the ablation device ablates the ex vivo tissue, sets multiple temperature measuring points in the ex vivo tissue, continuously collects the first image of the ex vivo tissue ablation process, and the temperature values ​​of the temperature measuring points, obtains the relationship between each temperature measuring point and the RGB color value of the pixel corresponding to the temperature measuring point in the first image, and thus establishes the first relationship model.

[0029] During the actual ablation operation, the doctor obtains the real-time temperature value of the tissue surface through the real-time image of the tissue surface based on the first relationship model. That is, the real-time image of the tissue surface is obtained through the endoscope matched with the ablation needle, and the real-time temperature value of the tissue surface is obtained by reverse deduction through the RGB value of the image according to the first relationship model database, so that the doctor can adjust the ablation parameters in real time, and prevent the ablation operation from damaging other normal tissues while ensuring the ablation effect.

[0030] Since the RGB value of each pixel in the first image contains data from three channels, the first relationship model is very complex. In order to simplify the first relationship model, preferably, the first image is grayed to obtain a second image, and a corresponding relationship model between each temperature measurement point of the ex vivo tissue and the grayscale value of the corresponding pixel of the second image is further obtained, which is referred to as the second relationship model for short, so as to obtain the real-time temperature value corresponding to the tissue surface through the grayscale image of the real-time image of the tissue surface based on the second relationship model.

[0031] There are many methods for converting the RGB value of the first image into the gray value, all of which are prior art. For example, the following method can be used: The corresponding relationship between the RGB value of the first image and the gray value of the second image is: Gray=(R*19595+G*38469+B*7472)>>16, Where Gray is the gray value of a pixel in the second image, R is the red channel value of the corresponding pixel in the first image, G is the green channel value of the corresponding pixel in the first image, and B is the blue channel value of the corresponding pixel in the first image.

[0032] It should be noted that the first relationship model in the present invention can be continuously optimized and modified according to the temperature values ​​measured and the image information collected during the actual ablation surgery, in order to obtain a more accurate database.

[0033] In this embodiment, an experimental method is used to obtain the first relationship model. For the rigor of the experiment and to reduce errors, the equipment of this experiment will be as consistent as possible with the equipment of the surgical process. In addition, in order to keep the image information collected by the endoscope consistent with the image information of the tumor target tissue collected during the operation and reduce color difference, the experiment will simulate the surgical environment of human tissue.

[0034] Temperature recognition device, The temperature data change information obtained by matching the color of each pixel of the first image acquired in real time by the image acquisition device with the first relationship model is referred to as the second temperature change information.

[0035] 3D model simulation device The purpose of the doctor's three-dimensional image reconstruction is to convert the two-dimensional images of various sections of the human body, such as CT / MRI, into three-dimensional structures with the assistance of computer technology, which can be used to intuitively display the size and relative position relationship of various tissues, facilitating the doctor's preoperative diagnosis and surgical evaluation. In this embodiment, the three-dimensional model simulation device can be modeled using various types of existing software, such as 3D Slicer.

[0036] In order to accurately know the specific position of the first image collected in this embodiment in the entire tumor target tissue, after using image acquisition equipment such as CT and MRI to collect image data of the tumor and simulating a three-dimensional model of the tumor target tissue in the ablation system, the first image and the three-dimensional model of the tumor target tissue are aligned, and the real-time temperature values ​​of the first temperature change information and the second temperature change information are reflected on the three-dimensional model. The temperature changes inside and on the surface of the tumor target tissue can be intuitively displayed, and an internal temperature and surface temperature change monitoring system during tumor ablation is established.

[0037] Since the ablation shape of the ablation needle is ellipsoidal or spherical, there is no fixed rule for the shape of the tumor, and the best result of the operation is to completely ablate the tumor, and it is expected to achieve no thermal damage or minimal thermal damage, which requires accurate judgment of the ablation boundary of the tumor. During the operation, if the temperature in the center of the tumor is too high, some systemic problems such as tissue carbonization will occur, which requires a more accurate method for monitoring the internal temperature of the tumor. The ablation monitoring system based on data fusion of real-time temperature and real-time image feedback proposed in this embodiment can effectively monitor the internal and external changes of the tumor during the ablation process.

[0038] If the shape of the tumor is close to a circle, the ablation shape of the selected ablation needle is also a circle, which can achieve conformal ablation. As long as the temperature change on the tumor surface is determined, the ablation boundary of the tumor can be determined, and the ablation result of the tumor can be effectively controlled.

[0039] If the tumor is irregular in shape and cannot be ablated in one go, multiple thermocouples installed on the ablation needle can effectively measure the ablation range and calculate the number of ablations required based on the size of the tumor. The system can accurately control the ablation boundary in multiple ablations. Example

[0040] This embodiment proposes an ablation monitoring method based on data fusion of real-time temperature and real-time image feedback, which is applied to the above-mentioned thermal field monitoring system based on data fusion of real-time temperature and real-time image feedback, and includes the following steps: Use CT, MRI and other imaging equipment to collect imaging information of tumor target tissues, determine the specific location of target tissues, and do related work such as surgical planning; Inserting the ablation needle into the tumor target tissue; Insert the endoscope into the body through the channel 4 reserved on the ablation needle, and ensure that the endoscope can clearly collect image information on the surface of the tumor target tissue; Set the ablation parameters of the ablation needle and start ablation; The first temperature change information during the tumor ablation process is collected in real time by the temperature measuring element and displayed on the display interface of the ablation device; Acquire a first image in real time through an endoscope and obtain second temperature change information; The temperature recognition device searches the first relationship model for the temperature value corresponding to the color of each pixel of the first image, that is, obtains the second temperature change information of the surface of the tumor target tissue, and displays it in real time on the display interface of the ablation device.

[0041] This embodiment can also be improved as follows: generating a three-dimensional model of the tumor target tissue, registering the first image with the three-dimensional model, The first temperature change information and the second temperature change information are displayed in real time on the three-dimensional model, thereby obtaining real-time temperature change information inside and on the surface of the tumor tissue.

[0042] Real-time information of the first image is continuously collected, and second temperature change information on the three-dimensional model is obtained through a first relationship model database pre-stored in the ablation system.

[0043] In this embodiment, the first relationship model is obtained by using the experimental method in the first embodiment, and the first relationship model is obtained according to the RGB value of each pixel in the first image and the measured temperature value.

[0044] In this embodiment, the second relationship model library is obtained using the method in the first embodiment, the first image is grayed to obtain the second image, and the correspondence between each temperature measurement point of the ex vivo tissue and the gray value of the corresponding pixel of the second image is further obtained.

[0045] In this embodiment, isotherms can also be used to establish a first thermal field based on the first temperature change information, and a second thermal field based on the second temperature change information, and then the first thermal field and the second thermal field are displayed on a three-dimensional model of the tumor. In this way, the thermal field change information of the entire tumor can be established to effectively monitor the ablation process of the tumor.

[0046] The technical solutions proposed in Embodiment 1 and Embodiment 2 of the present invention can be used in ablation surgeries such as microwave, radio frequency, and ultrasound.

[0047] It should be noted that the above schematically describes the present invention and its implementation methods, which are not restrictive, and the drawings show only one of the implementation methods of the present invention. Therefore, if a person skilled in the art is inspired by it and does not deviate from the purpose of the invention, and does not creatively design methods and embodiments similar to the technical solution, they should all fall within the scope of protection of the present invention.

Claims

1. Ablation monitoring system based on real-time temperature and image feedback data, characterized in that: include A temperature acquisition device collects the first temperature change information of the tumor during the ablation process in real time; an ablation device, configured to provide energy required to ablate a tumor, and equipped with a model of a corresponding relationship between color and temperature of a tumor surface image, referred to as a first relationship model; An image acquisition device, which acquires image information of the tumor surface ablation process in real time, referred to as the first image; a temperature recognition device, used for matching the color of each pixel of the first image with the first relationship model to obtain the second temperature change information; The three-dimensional model simulation device establishes a three-dimensional model of the tumor; and displays the first temperature change information and the second temperature change information on the three-dimensional model in real time.

2. The ablation monitoring system based on real-time temperature and image feedback data according to claim 1, characterized in that: The temperature collection device includes an ablation needle, and a double-layer outer sleeve consisting of a first elastic outer sleeve and a second elastic outer sleeve is provided on the outside of the needle rod of the ablation needle. At least one temperature measuring element and a wire connecting the temperature measuring element are provided between the first elastic outer sleeve and the second elastic outer sleeve. The temperature measuring elements are equidistantly distributed axially along the outside of the needle rod.

3. The ablation monitoring system based on real-time temperature and image feedback data according to claim 2, characterized in that: The needle rod is also provided with a sleeve, and the sleeve is provided with a channel for the shooting element of the image acquisition device to pass freely.

4. The ablation monitoring system based on real-time temperature and image feedback data according to claim 2, characterized in that: The shooting element of the image acquisition device is a shooting element that can pass through a natural cavity.

5. An ablation monitoring method using the data based on real-time temperature and image feedback according to claim 1, comprising the following steps: Real-time acquisition of first temperature change information during tumor ablation; Collecting the first image in real time and obtaining second temperature change information; The ablation range is monitored according to the first temperature change information and the second temperature change information.

6. The ablation monitoring method based on real-time temperature and image feedback data according to claim 5, characterized in that: The method also includes generating a first thermal field according to the first temperature change information.

7. The ablation monitoring method based on real-time temperature and image feedback data according to claim 5, characterized in that: The method also includes registering the first image and the three-dimensional model, and then generating a second thermal field according to second temperature change information.

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